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Pontifical Catholic University of Rio de Janeiro
1.
ORFELINDA AVALO CORTEZ.
[en] SYNTHESIS AND CHARACTERIZATION OF NANOSTRUCTURED
IRON-NICKEL ALLOYS.
Degree: 2009, Pontifical Catholic University of Rio de Janeiro
URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12975 
► [pt] Oxido de níquel e hematita nanoestruturadas foram sintetizadas a partir da decomposição térmica de nitrato de níquel hexahidratado e nitrato férrico nonahidratado respectivamente, na…
(more)
▼ [pt] Oxido de níquel e hematita nanoestruturadas foram
sintetizadas a partir da decomposição térmica de nitrato de níquel
hexahidratado e nitrato férrico nonahidratado respectivamente, na
faixa de temperatura de 350-450°C com variações no tempo reacional.
Os tamanhos de cristalito do NiO e Fe2O3 foram estimados a partir
dos difractogramas de Difração de Raios-X (XRD) utilizando os
software PowderCell e Topas. Foi observado que o tamanho de
cristalito varia em função da temperatura de sínteses. O resultado
mais significante foi observado nos cristalitos de NiO os quais
aumentam de 31 nm (T=350°C, 3hr) a 98 nm (T=450°C, 5hr). Foram
realizados estudos cinéticos da redução NiO e Fe2O3 por hidrogênio
na faixa de temperatura de 250-600°C. Ligas ferroníquel
nanoestruturadas com composições FexNi100-x (x = 25, 50, and 75 w%)
têm sido preparadas com sucesso por decomposição térmica de
nitratos (formação de óxidos) e posterior redução com hidrogênio a
700ºC (formação das ligas). As ligas Fe-Ni, caracterizadas por
difração de raios-X mostraram tamanhos de cristalito da ordem de
25nm. A fase rica em Ni, liga Fe25Ni75, apresentou uma estrutura
γ(FCC). A liga Fe50Ni50 apresentou a existência de uma estrutura
tetragonal. A fase rica em Fe, liga Fe75Ni25, contém uma mistura de
fases α(BCC) e γ(FCC). A coexistência das fases e atribuída à
segregação de fases que acontece nestas ligas como resultado da
difusão atômica. A partir dos resultados das medições magnéticas
efetuadas a 300K, pode-se estabelecer que as ligas Fe-Ni
nanoestruturadas tem um comportamento
superparamagnético.
[en] Nickel oxide and hematite nanostructured were
successfully prepared by thermal decomposition from nickel nitrate
hexahydrate and ferric nitrate nonahydrate in the temperature range
of 350-450°C with variation of the time. The average crystallite
sizes of NiO and Fe2O3 were estimated from X-ray diffraction (XRD)
peaks using the PowderCell and Topas software. We observed that the
crystallite size changes as a function of synthesis temperature.
The significant result was the large size of the resulting NiO
crystallites, which increased from 31nm (T=350°C, 3hr) to 98nm
(T=450°C, 5hr). Kinetic studies of the reduction of NiO and Fe2O3
by hydrogen in the temperature range 250-600°C have been
investigated. Nanostructured Fe-Ni alloys with compositions
FexNi100-x (x = 25, 50, and 75 w%) have been successively prepared
by thermal decomposition from mixtures of nitrates (formation of
oxides) and reduction by hydrogen at 700ºC (formation of alloys).
The Fe-Ni alloys, characterized by X-ray diffraction show
crystallites sizes about 25nm. The Nirich phase, Fe25Ni75 alloys
show the existence of γ(FCC) phase. The Fe50Ni50 alloy
show the existence of tetragonal phase. The Fe-rich phase, Fe75Ni25
alloy, contain a mixture of α(BCC) and γ(FCC)
phases. The coexistence of these phases is attributed to phase
segregation occurring in these alloys as a result of enhanced
atomic diffusion. It was inferred from results of magnetic
measurements at 300K, that…
Advisors/Committee Members: FRANCISCO JOSE MOURA.
Subjects/Keywords: [pt] LIGAS FERRONIQUEL; [en] IRON-NICKEL ALLOYS; [pt] DECOMPOSICAO TERMICA; [en] THERMAL DECOMPOSITION; [pt] REDUCAO POR HIDROGENIO; [en] REDUCTION BY HYDROGEN
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APA (6th Edition):
CORTEZ, O. A. (2009). [en] SYNTHESIS AND CHARACTERIZATION OF NANOSTRUCTURED
IRON-NICKEL ALLOYS. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12975
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
CORTEZ, ORFELINDA AVALO. “[en] SYNTHESIS AND CHARACTERIZATION OF NANOSTRUCTURED
IRON-NICKEL ALLOYS.” 2009. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 17, 2021.
http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12975.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
CORTEZ, ORFELINDA AVALO. “[en] SYNTHESIS AND CHARACTERIZATION OF NANOSTRUCTURED
IRON-NICKEL ALLOYS.” 2009. Web. 17 Jan 2021.
Vancouver:
CORTEZ OA. [en] SYNTHESIS AND CHARACTERIZATION OF NANOSTRUCTURED
IRON-NICKEL ALLOYS. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2009. [cited 2021 Jan 17].
Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12975.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
CORTEZ OA. [en] SYNTHESIS AND CHARACTERIZATION OF NANOSTRUCTURED
IRON-NICKEL ALLOYS. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2009. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12975
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Urbana-Champaign
2.
Averill, Ben.
Comparing the thermal decomposition kinetics of cane and beet sucrose to examine thermal behavior differences.
Degree: PhD, Food Science & Human Nutrition, 2018, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/101158
► Sucrose from cane and beet sources is greater than 99.8% pure. However, sucrose from both sources displays different thermal behavior. In their DSC thermal profiles,…
(more)
▼ Sucrose from cane and beet sources is greater than 99.8% pure. However, sucrose from both sources displays different
thermal behavior. In their DSC
thermal profiles, cane sucrose displays a small endothermic peak (small peak) before the main endothermic peak (large peak), which is not present in beet. The presence of the small peak results in a lower onset temperature for
thermal decomposition in cane sucrose, compared to beet. To compare the
thermal behavior of these sucrose sources, the kinetic parameters for the
thermal decomposition of crystalline cane and beet sucrose were determined herein. Since sucrose
thermal decomposition is a complicated process, causing the formation of
decomposition products, loss of crystalline structure, and, at sufficiently high temperatures, these events can overlap with true melting, a variety of kinetic methods were used to characterize the
thermal behavior of the system.
Initially, a nonisothermal kinetic method was used to obtain the kinetic parameters for cane and beet sucrose
thermal decomposition. Commercial beet sucrose (US beet) exhibited a higher activation energy (Ea) than either analytical grade (Sigma cane) or commercial cane sucrose (US cane), which displayed similar Ea values. The higher Ea for US beet suggested that
thermal decomposition is inhibited in beet sucrose, compared to cane. The nonisothermal method was also used to explore the effect of lot-to-lot variation on the kinetic parameters of Sigma cane to fully characterize the
thermal behavior of the material. While there were differences in the
thermal behavior parameters for each lot, the kinetic parameters for the small peak were similar for all lots, suggesting that lot-to-lot variation does not lead to differences in the kinetic parameters. Although there were not differences in the small peak kinetic parameters, the use of several lots does provide a better predictor of the variability that can occur when different lots of sucrose are used in a product.
Next, isothermal experiments were performed to assess the accuracy of the kinetic parameters obtained from nonisothermal experiments. To compare these experimental conditions, the predicted rate constant (k) and half-life (t1/2) values determined from nonisothermal experiments were compared to those obtained from isothermal experiments at 130°C. Based on the results of the isothermal experiments, the nonisothermal kinetic parameters overestimate k for cane-sourced sucrose, and underestimate k for beet sucrose. To further explore the differences between nonisothermal and isothermal methods, the Ea for sucrose
thermal decomposition was determined using the isothermal isoconversional kinetic method, which allows for the Ea to be determined as a function of the extent of the reaction (α). Additionally, the use of isothermal methods allows for the kinetic parameters to be determined without the interference of the overlap of true melting. Under isothermal conditions, US cane displayed the largest Ea value at 2% α, while the Ea values displayed by Sigma cane…
Advisors/Committee Members: Schmidt, Shelly J (advisor), Bohn, Dawn M (Committee Chair), Cadwallader, Keith (committee member), Takhar, Pawan S (committee member), Thomas, Leonard C (committee member).
Subjects/Keywords: Sucrose; thermal decomposition; kinetics
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APA (6th Edition):
Averill, B. (2018). Comparing the thermal decomposition kinetics of cane and beet sucrose to examine thermal behavior differences. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/101158
Chicago Manual of Style (16th Edition):
Averill, Ben. “Comparing the thermal decomposition kinetics of cane and beet sucrose to examine thermal behavior differences.” 2018. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 17, 2021.
http://hdl.handle.net/2142/101158.
MLA Handbook (7th Edition):
Averill, Ben. “Comparing the thermal decomposition kinetics of cane and beet sucrose to examine thermal behavior differences.” 2018. Web. 17 Jan 2021.
Vancouver:
Averill B. Comparing the thermal decomposition kinetics of cane and beet sucrose to examine thermal behavior differences. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2018. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/2142/101158.
Council of Science Editors:
Averill B. Comparing the thermal decomposition kinetics of cane and beet sucrose to examine thermal behavior differences. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2018. Available from: http://hdl.handle.net/2142/101158
Pontifical Catholic University of Rio de Janeiro
3.
FELIPE ZANONE RIBEIRO MONTEIRO.
[en] STUDY OF THE THERMAL DECOMPOSITION OF GREEN COCONUT
FIBER IN THE PRESENCE OF A NANO STRUCTURED CATALYST.
Degree: 2018, Pontifical Catholic University of Rio de Janeiro
URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32928
► [pt] Com aumento da preocupação político-ambiental, torna-se imperativo desenvolver processos eficientes em termos econômicos e energéticos para a produção sustentável de combustíveis e produtos químicos.…
(more)
▼ [pt] Com aumento da preocupação político-ambiental,
torna-se imperativo desenvolver processos eficientes em termos
econômicos e energéticos para a produção sustentável de
combustíveis e produtos químicos. A liquefação hidrotérmica (HTL) é
um processo para a transformação de materiais orgânicos, tais como
bio-resíduos ou biomassa, em óleo bruto, em temperaturas usualmente
inferiores a 400 graus Celsius sob altas pressões na presença de
água, e, dependendo do processo, de um catalisador. Nesse contexto,
é importante entender o comportamento de degradação térmica do
material em atmosfera inerte, no sentido de se investigar a
possibilidade de quebra das cadeias poliméricas inicias em
moléculas menores, que, mediante pressão, poderão ser convertidas
em novos produtos. Assim sendo, os objetivos do presente trabalho
estão associados ao estudo termogravimétrico (TG) da degradação
térmica da fibra do coco verde na presença de ferrita de cobalto
(Fe2CoO4), utilizada no intuito de gerar um efeito catalítico,
acelerando a degradação térmica das estruturas poliméricas
presentes, e, que possa ser usada posteriormente em uma rota HTL.
Os catalisadores foram produzidos a 1000 graus Celsius em
diferentes tempos de calcinação (3h, 6h e 9h), sendo, nas misturas
com a fibra, a fração mássica de óxido igual a 50 por cento. As
amostras de interesse para a pesquisa foram caracterizadas mediante
diferentes técnicas, tais como, a microscopia eletrônica de
varredura, para o estudo da morfologia e composição elementar,
difração de raios X, para a quantificação das fases presentes nas
amostras de ferrita, e espectroscopia de infravermelho, visando à
identificação das principais ligações químicas nas fibras, tanto
antes quanto durante o tratamento térmico. Dentre todos os ensaios
de TG realizados, os experimentos com o catalisador calcinado
durante 9h homogeneizado com gral de ágata foi o que mostrou uma
melhor resposta com relação à degradação térmica das fibras. Os
resultados sugerem ainda que, tanto o tempo de calcinação, quanto a
natureza do processo de mistura apresentam efeitos significativos
sobre a cinética de degradação.
[en] With increasing political-environmental concern,
it becomes imperative to develop efficient processes in economic
and energy terms for the sustainable production of fuels and
chemical products. Hydrothermal liquefaction (HTL) is a process for
the transformation of organic materials such as bio-waste or
biomass into crude oil at temperatures usually below 400 degrees
Celsius under high pressures in the presence of water and,
depending on the process, of a catalyst. In this context, it is
important to understand the behavior of thermal degradation of the
material under inert atmosphere, in order to investigate the
possibility of breaking the initial polymer chains into smaller
molecules, which, under pressure, can be converted into new
products. The objectives of the present work are associated to the
thermogravimetric study (TG) in the thermal degradation of the
green coconut fiber in the presence of a cobalt…
Advisors/Committee Members: FRANCISCO JOSE MOURA.
Subjects/Keywords: [pt] BIOMASSA; [en] BIOMASS; [pt] DECOMPOSICAO TERMICA; [en] THERMAL DECOMPOSITION; [pt] FIBRA DO COCO VERDE; [en] GREEN COCONUT FIBER; [pt] LIQUEFACAO HIDROTERMICA; [en] HYDROTHERMAL LIQUEFACTION
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APA (6th Edition):
MONTEIRO, F. Z. R. (2018). [en] STUDY OF THE THERMAL DECOMPOSITION OF GREEN COCONUT
FIBER IN THE PRESENCE OF A NANO STRUCTURED CATALYST. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32928
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
MONTEIRO, FELIPE ZANONE RIBEIRO. “[en] STUDY OF THE THERMAL DECOMPOSITION OF GREEN COCONUT
FIBER IN THE PRESENCE OF A NANO STRUCTURED CATALYST.” 2018. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 17, 2021.
http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32928.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
MONTEIRO, FELIPE ZANONE RIBEIRO. “[en] STUDY OF THE THERMAL DECOMPOSITION OF GREEN COCONUT
FIBER IN THE PRESENCE OF A NANO STRUCTURED CATALYST.” 2018. Web. 17 Jan 2021.
Vancouver:
MONTEIRO FZR. [en] STUDY OF THE THERMAL DECOMPOSITION OF GREEN COCONUT
FIBER IN THE PRESENCE OF A NANO STRUCTURED CATALYST. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2018. [cited 2021 Jan 17].
Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32928.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
MONTEIRO FZR. [en] STUDY OF THE THERMAL DECOMPOSITION OF GREEN COCONUT
FIBER IN THE PRESENCE OF A NANO STRUCTURED CATALYST. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2018. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=32928
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Pontifical Catholic University of Rio de Janeiro
4.
BRUNO MUNIZ E SOUZA.
[en] PRODUCTION OF MGO THROUGH MGSO4 DECOMPOSITION IN THE
PRESENCE OF CARBON.
Degree: 2019, Pontifical Catholic University of Rio de Janeiro
URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37645
► [pt] O sulfato de magnésio se caracteriza como um possível co-produto de alguns processos hidrometalúrgicos envolvendo concentrados minerais portadores desse metal quando submetidos à lixiviação…
(more)
▼ [pt] O sulfato de magnésio se caracteriza como um
possível co-produto de alguns processos hidrometalúrgicos
envolvendo concentrados minerais portadores desse metal quando
submetidos à lixiviação envolvendo ácido sulfúrico. Dentro do
contexto dos fluxogramas de processamento desses concentrados, uma
etapa bastante comum é a neutralização da solução, usualmente
levada a efeito por meio da solubilização de óxido de cálcio. Este,
por sua vez, pode ser substituído por óxido de magnésio desde que
determinadas propriedades, tais como superfície de contato e
reatividade, estejam adequadas aos requisitos desta etapa. Desta
forma, o processo de decomposição térmica do sulfato de magnésio,
aparentemente, não se configura como uma possível rota de
processamento visto que ocorre numa temperatura de aproximadamente
1100 graus Celsius, significativamente alta para a formação de um
óxido de magnésio que atenda às condições necessárias para uma
neutralização eficiente. O estudo termodinâmico realizado sugere
que na presença de agentes redutores como o carbono, ocorre uma
diminuição na temperatura, para aproximadamente 400 graus Celsius,
a partir da qual a transformação do sulfato em óxido de magnésio é
teoricamente viável. Assim sendo, os objetivos do trabalho de
pesquisa estão associados com a avaliação do comportamento do
sistema reacional constituído por MgSO4 quando na presença de
carbono oriundo de carvão vegetal. O estudo contempla também a
caracterização dos materiais obtidos a fim de verificar a obtenção
do MgO e avaliar se as propriedades do material encontram-se
adequadas para a sua utilização como agente regulador de pH tal
como o CaO. Desta forma, além das técnicas de microscopia
eletrônica de varredura e difração de Raios-X, também é prevista a
quantificação da reatividade do produto em soluções ácidas. As
análises realizadas com as variáveis, excesso de agente redutor,
temperatura, vazão de arraste e homogeneidade da amostra, mostraram
que a temperatura é a variável que mais influência a decomposição
do MgSO4. Entre todos os ensaios analisados, os experimentos a 900
graus Celsius e com tempos de 25 e 30 minutos foram os que
indicaram os melhores resultados experimentais de conversão,
atingindo uma conversão próxima de 100 por cento. As análises de
caracterização, em DR-X e MEV/EDS, indicaram que o MgO foi formado
ao fim da reação. O teste de reatividade indicou que o MgO obtido
pode ser utilizado como regulador de pH, atendendo a proposta do
trabalho.
[en] Magnesium sulfate is characterized as a possible
co-product of some Hydrometallurgical Processes involving mineral
concentrates that has this metal when subjected to leaching
involving sulfuric acid. In the context of the processes flowchart,
a fairly common step is the neutralization of the solution that
usually takes effect through the solubility of calcium oxide. This,
in turn, can be substituted for magnesium oxide as long as these
properties, such as contact surface and reactivity, are suitable
for the requirements of this step. Thus, the thermal…
Advisors/Committee Members: EDUARDO DE ALBUQUERQUE BROCCHI.
Subjects/Keywords: [pt] DECOMPOSICAO TERMICA; [en] THERMAL DECOMPOSITION; [pt] OXIDO DE MAGNESIO; [en] MAGNESIUM OXIDE; [pt] SULFATO DE MAGNESIO; [en] MAGNESIUM SULFATE; [pt] REDUCAO CARBOTERMICA; [en] CARBOTHERMIC REDUCTION
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APA (6th Edition):
SOUZA, B. M. E. (2019). [en] PRODUCTION OF MGO THROUGH MGSO4 DECOMPOSITION IN THE
PRESENCE OF CARBON. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37645
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
SOUZA, BRUNO MUNIZ E. “[en] PRODUCTION OF MGO THROUGH MGSO4 DECOMPOSITION IN THE
PRESENCE OF CARBON.” 2019. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 17, 2021.
http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37645.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
SOUZA, BRUNO MUNIZ E. “[en] PRODUCTION OF MGO THROUGH MGSO4 DECOMPOSITION IN THE
PRESENCE OF CARBON.” 2019. Web. 17 Jan 2021.
Vancouver:
SOUZA BME. [en] PRODUCTION OF MGO THROUGH MGSO4 DECOMPOSITION IN THE
PRESENCE OF CARBON. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2019. [cited 2021 Jan 17].
Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37645.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
SOUZA BME. [en] PRODUCTION OF MGO THROUGH MGSO4 DECOMPOSITION IN THE
PRESENCE OF CARBON. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2019. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37645
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Pontifical Catholic University of Rio de Janeiro
5.
[No author].
[pt] DECOMPOSIÇÃO TÉRMICA DO SULFATO DE ZINCO NA PRESENÇA DE
AGENTES MODIFICADORES DO MECANISMO REACIONAL.
Degree: 2020, Pontifical Catholic University of Rio de Janeiro
URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=49393
► [pt] O hidrogênio apresenta-se como um potencial combustível alternativo em substituição aos combustíveis fósseis e, por essa razão, estudos e pesquisas sobre as rotas de…
(more)
▼ [pt] O hidrogênio apresenta-se como um potencial
combustível alternativo em substituição aos combustíveis fósseis e,
por essa razão, estudos e pesquisas sobre as rotas de produção e
armazenamento desse recurso estão em voga no meio científico. Os
métodos para obtenção de H2 são diversos, no entanto, nem todos os
métodos são provenientes de fontes renováveis. Os ciclos
termoquímicos de quebra da molécula da água são alternativas
promissoras para a geração de H2. Neste contexto, o ciclo do
enxofre-iodo é um dos ciclos em destaque, caracterizando-se por um
processo em três etapas cuja terceira etapa é a etapa desafiadora
do ciclo, onde ocorre a decomposição do ácido sulfúrico que exige
um gasto energético elevado. A utilização de sulfatos metálicos
associados a agentes redutores e aditivos em substituição ao ácido
sulfúrico no ciclo enxofre-iodo tem sido estudada. Deste modo, o
presente trabalho de pesquisa avaliou a decomposição térmica do
sulfato de zinco monohidratado na presença dos agentes
modificadores enxofre elementar, Pd-(gama)Al2O3, CeO2 e CeO2/ZnO
que estimulam a transformação do trióxido de enxofre no respectivo
dióxido. Além de um estudo termodinâmico do sistema reacional e
análises térmicas via TG que indicaram uma mudança no comportamento
da decomposição do sulfato na presença do agente redutor e dos
aditivos, o trabalho previu a caracterização dos produtos
reacionais indicando a presença do óxido de zinco e um estudo
cinético dos sistemas na presença dos agentes mencionados,
permitindo o cálculo das energias de ativação e dos parâmetros
cinéticos. A apreciação termodinâmica indicou um aspecto favorável
quanto a diminuição da temperatura de decomposição do sulfato de
zinco assim como no que diz respeito à transformação de SO3 em SO2.
Na presença de Pd-(gama)Al2O3 a temperatura final da decomposição
do sulfato ocorreu 100 graus Celsius abaixo da temperatura
habitual. A perda de massa total calculada para a decomposição do
sulfato puro foi de 55 por cento. Nos estudos com a presença dos
agentes as perdas de massa total calculadas foram 60 por cento, 54
por cento, 62 por cento, 57 por cento correspondentes ao sulfato de
zinco na presença do enxofre elementar, Pd-(gama)Al2O3, CeO2 e
CeO2/ZnO, respectivamente.
[en] Hydrogen presents itself as a potential
alternative fuel to replace fossil fuels and, for this reason,
studies and research on the production and storage routes of this
resource are in vogue in the scientific community. The methods for
obtaining H2 are diverse, however, not all methods are from
renewable sources. The thermochemical cycles of splitting water are
promising alternatives. In this context, the sulfur-iodine cycle is
one of the highlighted cycles, characterized by a three-stage
process whose third stage is the challenging stage of the cycle,
where the decomposition of sulfuric acid occurs, which requires a
high energy expenditure for formation selection of sulfur dioxide
and oxygen. The use of metal sulfates associated with reducing
agents and additives in substitution for sulfuric…
Advisors/Committee Members: RODRIGO FERNANDES MAGALHÃES DE SOUZA, RODRIGO FERNANDES MAGALHÃES DE SOUZA.
Subjects/Keywords: [pt] DECOMPOSICAO TERMICA; [pt] TG; [pt] ADITIVO; [pt] AGENTE REDUTOR; [pt] SULFATO DE ZINCO; [pt] CATALISADOR; [en] THERMAL DECOMPOSITION; [en] TGA; [en] ADDITIVE; [en] REDUCING AGENT; [en] ZINC SULFATE; [en] CATALYST
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APA (6th Edition):
author], [. (2020). [pt] DECOMPOSIÇÃO TÉRMICA DO SULFATO DE ZINCO NA PRESENÇA DE
AGENTES MODIFICADORES DO MECANISMO REACIONAL. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=49393
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
author], [No. “[pt] DECOMPOSIÇÃO TÉRMICA DO SULFATO DE ZINCO NA PRESENÇA DE
AGENTES MODIFICADORES DO MECANISMO REACIONAL.” 2020. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 17, 2021.
http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=49393.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
author], [No. “[pt] DECOMPOSIÇÃO TÉRMICA DO SULFATO DE ZINCO NA PRESENÇA DE
AGENTES MODIFICADORES DO MECANISMO REACIONAL.” 2020. Web. 17 Jan 2021.
Vancouver:
author] [. [pt] DECOMPOSIÇÃO TÉRMICA DO SULFATO DE ZINCO NA PRESENÇA DE
AGENTES MODIFICADORES DO MECANISMO REACIONAL. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2020. [cited 2021 Jan 17].
Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=49393.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
author] [. [pt] DECOMPOSIÇÃO TÉRMICA DO SULFATO DE ZINCO NA PRESENÇA DE
AGENTES MODIFICADORES DO MECANISMO REACIONAL. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2020. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=49393
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Pontifical Catholic University of Rio de Janeiro
6.
RENATA BULCAO NOFAL.
[en] MODELING, SIMULATION AND PARAMETER ESTIMATION OF
THERMAL DECOMPOSITION OF POTASSIUM ALUM.
Degree: 2019, Pontifical Catholic University of Rio de Janeiro
URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37268
► [pt] O potássio é um íon essencial para a nutrição de plantas, geralmente fornecido sob a forma de cloretos e sulfatos. De acordo com a…
(more)
▼ [pt] O potássio é um íon essencial para a nutrição de
plantas, geralmente fornecido sob a forma de cloretos e sulfatos.
De acordo com a disponibilidade e demanda brasileira de
fertilizantes agrícolas, a importação de compostos portadores desse
elemento químico é mandatória para atender a enorme demanda por
esse nutriente. Assim, iniciativas que buscam fontes alternativas
de potássio tornam-se cada vez mais interessantes e economicamente
atraentes. Uma rota potencial está associada com a digestão com
ácido sulfúrico de minerais portadores de glauconita e operações
unitárias sequenciais para recuperar compostos de alumínio, ferro,
magnésio e potássio. No contexto deste processo químico, o alúmen
de potássio dodecahidrato aparece como um produto intermediário
relevante que permite a recuperação seletiva de potássio e alumínio
através de decomposição térmica seguida de solubilização em água e
filtração. Com base no que foi dito, o presente trabalho investiga
a cinética da decomposição do alúmen de potássio dodecahidratado
sob condições não-redutoras e redutoras, e um novo modelo
matemático é proposto para descrever a perda de massa ao longo do
tempo. Uma abordagem estocástica, com o uso do método de otimização
enxame de partículas, é empregada para estimar os parâmetros
desconhecidos do modelo. As previsões do modelo são validadas por
dados experimentais obtidos via análise termogravimétrica dinâmica
em diferentes atmosferas de reação (inerte e oxidante), e com a
presença ou não de agente redutor (finos de coque metalúrgico). Com
os parâmetros do modelo validado, é possível usar o mesmo para
monitorar as composições mássicas de todos os compostos presentes
no meio assim como empregar o modelo futuramente para monitoramento
online uma vez que sua simulação leva menos do que 1 s para simular
20 min de decomposição térmica.
[en] Potassium is an essential ion for plant
nutrition, usually supplied in the form of chlorides and sulfates.
According to Brazilian availability and demand of agriculture
fertilizers, the importation of compounds carrying this chemical
element is mandatory in order to fulfill the huge demand for this
nutrient. So initiatives looking for alternative sources of
potassium become increasingly interesting and economically
attractive. A potential route is associated with the sulfuric
digestion of glauconite-bearing greensands and sequential unit
operations in order to recover aluminum, iron, magnesium and
potassium compounds. In the context of this chemical process, the
potassium alum dodecahydrate appears as a relevant intermediate
product that allows the selective recovery of potassium and
aluminum through thermal decomposition followed by solubilization
in water and filtration. Based on what was said, the present work
investigates the kinetics of potassium alum dodecahydrate
decomposition under nonreductive and reductive conditions, and a
novel mathematical model is proposed to describe the weight loss
during time. A stochastic approach approach, using particle swarm
optimization method, is employed…
Advisors/Committee Members: AMANDA LEMETTE TEIXEIRA BRANDAO, AMANDA LEMETTE TEIXEIRA BRANDAO.
Subjects/Keywords: [pt] MODELAGEM; [en] MODELLING; [pt] ESTIMACAO DE PARAMETROS; [en] PARAMETER ESTIMATION; [pt] DECOMPOSICAO TERMICA; [en] THERMAL DECOMPOSITION; [pt] ENXAME DE PARTICULAS; [en] PARTICLE SWARM; [pt] ALUMEN DE POTASSIO; [en] POTASSIUM ALUM
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CSE |
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APA (6th Edition):
NOFAL, R. B. (2019). [en] MODELING, SIMULATION AND PARAMETER ESTIMATION OF
THERMAL DECOMPOSITION OF POTASSIUM ALUM. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37268
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
NOFAL, RENATA BULCAO. “[en] MODELING, SIMULATION AND PARAMETER ESTIMATION OF
THERMAL DECOMPOSITION OF POTASSIUM ALUM.” 2019. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 17, 2021.
http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37268.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
NOFAL, RENATA BULCAO. “[en] MODELING, SIMULATION AND PARAMETER ESTIMATION OF
THERMAL DECOMPOSITION OF POTASSIUM ALUM.” 2019. Web. 17 Jan 2021.
Vancouver:
NOFAL RB. [en] MODELING, SIMULATION AND PARAMETER ESTIMATION OF
THERMAL DECOMPOSITION OF POTASSIUM ALUM. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2019. [cited 2021 Jan 17].
Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37268.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
NOFAL RB. [en] MODELING, SIMULATION AND PARAMETER ESTIMATION OF
THERMAL DECOMPOSITION OF POTASSIUM ALUM. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2019. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=37268
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
7.
Hermouet, Fabien.
Développement d'une approche innovante de modélisation de la cinétique de décomposition thermique des matériaux solides en espaces confinés sous-ventilés. Application aux incendies en tunnel : Development of an Innovative Modelling Approach of the Thermal Decomposition Kinetics of Solid Mateirals in Confined Under Ventilated Environments. Application to Tunnel Fires.
Degree: Docteur es, Energétique, thermique, combustion, 2015, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique
URL: http://www.theses.fr/2015ESMA0020
► Les incendies de tunnels sont des phénomènes violents, à l’évolution rapide qui engendrent la plupart du temps des dommages importants aux personnes et aux biens.…
(more)
▼ Les incendies de tunnels sont des phénomènes violents, à l’évolution rapide qui engendrent la plupart du temps des dommages importants aux personnes et aux biens. La sécurité incendie dans les tunnels routiers est basée sur l’utilisation de modèles empiriques très simplifiés de description de l’évolution de la cinétique de développement de l’incendie. Ces modèles ne prennent cependant pas en compte le type de combustible impliqués dans le phénomène, tels que les polymères constitutifs des enveloppes des véhicules routiers, ni leurs réactivité en phase solide (décomposition thermique). Dans l’optique de faire évoluer la description de l’incendie en fonction des conditions ambiantes caractéristiques d’un tunnel, un modèle prédictif de la décomposition thermique des matériaux a été développé. Ce modèle mathématique a été construit sur la base d’une approche expérimentale à petite échelle faisant intervenir le dispositif du cône calorimètre à atmosphère contrôlée couplé à un spectromètre infrarouge à transformée de Fourrier. Trois matériaux ont fait l’objet d’une étude approfondie de leur décomposition thermique, en fonction de deux paramètres clés influençant la décomposition des solides lors d’un incendie de tunnel : la concentration d’oxygène ambiante et l’éclairement énergétique imposé aux matériaux. Les résultats obtenus pour les trois matériaux choisis (une mousse Polyisocyanurate, un Ethylène Propylène Diène Monomère et un Acrylonitrile Butadiène Styrène) ont été utilisés pour la construction de régressions polynomiales multifactorielles, méthode également connue sous le nom de méthodologie des surfaces de réponses.Le modèle permet de définir la réponse de la cinétique de décomposition (variable expliquée) et son évolution, en fonction de la concentration d’oxygène locale et de l’éclairement énergétique imposé à la surface d’un matériau (variables explicatives). La comparaison des résultats numériques et expérimentaux a alors montré la pertinence de ce type d’approche
Tunnel fires are severe phenomenon whose evolution, usually very fast, can lead to important damages to persons and properties. Tunnel fire safety is based on the use of empirical models, very simplified that describes the evolution of the fire kinetic. Nevertheless, these models does not take into account neither the type of material that are involved in the phenomenon, such as constitutive polymers of road vehicles nor their reactivity in solid phase (thermal decomposition). In order to provide an evolution of the fire description, function of the conditions usually encountered in a tunnel, a predictive model aiming to describe materials’ thermal decomposition has been developed. This mathematical model has been established on the basis of an experimental approach, at small scale, using the Controlled Atmosphere Cone Calorimeter coupled to a Fourier Transform Infrared Spectrometer. The thermal degradation of three different materials (Polyisocyanurate foam, Acrylonitrile Butadiene Styrene and Ethylene Propylene Diene Monomer) has been thoroughly…
Advisors/Committee Members: Rogaume, Thomas (thesis director), Guillaume, Éric (thesis director), Richard, Franck (thesis director).
Subjects/Keywords: Cinétique de décomposition thermique; Thermal decomposition kinetcs
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APA (6th Edition):
Hermouet, F. (2015). Développement d'une approche innovante de modélisation de la cinétique de décomposition thermique des matériaux solides en espaces confinés sous-ventilés. Application aux incendies en tunnel : Development of an Innovative Modelling Approach of the Thermal Decomposition Kinetics of Solid Mateirals in Confined Under Ventilated Environments. Application to Tunnel Fires. (Doctoral Dissertation). Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique. Retrieved from http://www.theses.fr/2015ESMA0020
Chicago Manual of Style (16th Edition):
Hermouet, Fabien. “Développement d'une approche innovante de modélisation de la cinétique de décomposition thermique des matériaux solides en espaces confinés sous-ventilés. Application aux incendies en tunnel : Development of an Innovative Modelling Approach of the Thermal Decomposition Kinetics of Solid Mateirals in Confined Under Ventilated Environments. Application to Tunnel Fires.” 2015. Doctoral Dissertation, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique. Accessed January 17, 2021.
http://www.theses.fr/2015ESMA0020.
MLA Handbook (7th Edition):
Hermouet, Fabien. “Développement d'une approche innovante de modélisation de la cinétique de décomposition thermique des matériaux solides en espaces confinés sous-ventilés. Application aux incendies en tunnel : Development of an Innovative Modelling Approach of the Thermal Decomposition Kinetics of Solid Mateirals in Confined Under Ventilated Environments. Application to Tunnel Fires.” 2015. Web. 17 Jan 2021.
Vancouver:
Hermouet F. Développement d'une approche innovante de modélisation de la cinétique de décomposition thermique des matériaux solides en espaces confinés sous-ventilés. Application aux incendies en tunnel : Development of an Innovative Modelling Approach of the Thermal Decomposition Kinetics of Solid Mateirals in Confined Under Ventilated Environments. Application to Tunnel Fires. [Internet] [Doctoral dissertation]. Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique; 2015. [cited 2021 Jan 17].
Available from: http://www.theses.fr/2015ESMA0020.
Council of Science Editors:
Hermouet F. Développement d'une approche innovante de modélisation de la cinétique de décomposition thermique des matériaux solides en espaces confinés sous-ventilés. Application aux incendies en tunnel : Development of an Innovative Modelling Approach of the Thermal Decomposition Kinetics of Solid Mateirals in Confined Under Ventilated Environments. Application to Tunnel Fires. [Doctoral Dissertation]. Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique; 2015. Available from: http://www.theses.fr/2015ESMA0020
Cornell University
8.
Kuo, Wei-Chih.
Thermal Decomposition Of Aqueous Glycerine Mixtures, Ethyl Acetate, Diethyl Carbonate, And Ethanol At High Temperatures In A Film Boiling Reactor.
Degree: PhD, Mechanical Engineering, 2014, Cornell University
URL: http://hdl.handle.net/1813/38943
► This study employs film boiling as a means to thermally decompose organic gas in a relatively low temperature liquid pool. Film boiling is a multiphase…
(more)
▼ This study employs film boiling as a means to thermally decompose organic gas in a relatively low temperature liquid pool. Film boiling is a multiphase heat transfer mode characterized by a vapor film surrounding a heated surface immersed in a pool of subcooled liquid. Due to the relatively low
thermal conductivity of gases compared to liquids, the vapor film acts as an insulating layer between the surface and liquid with potential to support a large temperature drop that can promote chemical conversion of the vapors flowing in the film. The vapor thus serves as a reactant which decomposes in a reactor configuration that is essentially self-assembled.
Decomposition by film boiling of the following organic liquids is discussed: aqueous glycerine (C3H5(OH)3) mixtures, ethyl acetate (CH3COOC2H5), diethyl carbonate ((CH3CH2O)2CO), and ethanol (C2H5(OH)). Ethyl acetate and diethyl carbonate decompose in a unimolecular process.
Thermal decomposition of aqueous glycerine mixtures is more complicated. Ethanol, which is a product of diethyl carbonate
decomposition, can thermally decompose in several routes which are discussed. The experimental results presented suggest that aqueous glycerol mixtures decompose by film boiling primarily into synthesis gas (a mixture of hydrogen (H2) and carbon monoxide (CO)), which can be used as an alternative fuel. Ethyl acetate and diethyl carbonate decompose by a unimolecular process as expected.
Advisors/Committee Members: Avedisian, C Thomas (chair), Datta, Ashim K (committee member), Zhang, Ke (committee member).
Subjects/Keywords: film boiling reactor; thermal decomposition; pyrolysis
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APA (6th Edition):
Kuo, W. (2014). Thermal Decomposition Of Aqueous Glycerine Mixtures, Ethyl Acetate, Diethyl Carbonate, And Ethanol At High Temperatures In A Film Boiling Reactor. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/38943
Chicago Manual of Style (16th Edition):
Kuo, Wei-Chih. “Thermal Decomposition Of Aqueous Glycerine Mixtures, Ethyl Acetate, Diethyl Carbonate, And Ethanol At High Temperatures In A Film Boiling Reactor.” 2014. Doctoral Dissertation, Cornell University. Accessed January 17, 2021.
http://hdl.handle.net/1813/38943.
MLA Handbook (7th Edition):
Kuo, Wei-Chih. “Thermal Decomposition Of Aqueous Glycerine Mixtures, Ethyl Acetate, Diethyl Carbonate, And Ethanol At High Temperatures In A Film Boiling Reactor.” 2014. Web. 17 Jan 2021.
Vancouver:
Kuo W. Thermal Decomposition Of Aqueous Glycerine Mixtures, Ethyl Acetate, Diethyl Carbonate, And Ethanol At High Temperatures In A Film Boiling Reactor. [Internet] [Doctoral dissertation]. Cornell University; 2014. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1813/38943.
Council of Science Editors:
Kuo W. Thermal Decomposition Of Aqueous Glycerine Mixtures, Ethyl Acetate, Diethyl Carbonate, And Ethanol At High Temperatures In A Film Boiling Reactor. [Doctoral Dissertation]. Cornell University; 2014. Available from: http://hdl.handle.net/1813/38943
Texas A&M University
9.
Han, Zhe.
Thermal Stability Studies of Ammonium Nitrate.
Degree: PhD, Chemical Engineering, 2016, Texas A&M University
URL: http://hdl.handle.net/1969.1/156911
► Ammonium nitrate (AN) is widely used in the fertilizer industry and is one of the most concentrated forms of nitrogen fertilizer. However, AN is associated…
(more)
▼ Ammonium nitrate (AN) is widely used in the fertilizer industry and is one of the most concentrated forms of nitrogen fertilizer. However, AN is associated with various hazards including fire and explosion, which have occurred continuously in the past. AN is not considered a flammable or combustible material at ambient temperature and pressure; however, it is a strong oxidizing agent that can detonate under certain conditions.
The primary goals of this work are to advance the understanding of the root causes associated with AN explosions and find out ways to make AN storage inherently safer by studying its
thermal stability. This research focuses on condition-dependent AN
decomposition, including the effect of additives, confinement, heating rate, temperature,
thermal history, and sample size. Pseudo-adiabatic and adiabatic calorimeters are used to study the characteristics of AN
decomposition. Thermodynamic and kinetic parameters are evaluated; models are proposed to predict the temperature rise of AN mixtures with additives;
decomposition pathways are analyzed; safer AN storage conditions are identified; and AN explosion phenomenology are reported. In addition, this work discusses the role of water as a chemical, interfering physically and chemically with AN-related fire scenarios possibly leading to explosions.
Thermal stability analysis showed that AN is stable up to approximately 200 °C. Sodium sulfate is a good inhibitor for AN in that its presence can mitigate AN
decomposition, while potassium chloride is a promoter because it intensifies the runaway reaction. AN should be separately stored from promoters, even when inhibitors are also present. Furthermore, exposure of AN to heat and storage in confined spaces should be avoided, and the size of AN piles should be limited. While water remains the choice for tackling AN-related fires, care should be taken in doing so. It must be understood that a significantly sufficient quantity of water should be used. Actually, evidence shows that insufficient quantities of water may exacerbate the fires and consequences.
This work demonstrates the complexity and the multiple studies required for making AN safer as a fertilizer, providing suggestions to the fertilizer industry. It can also serve as a model for studies on various reactive chemicals.
Advisors/Committee Members: Mannan, M. Sam (advisor), Holste, James (committee member), El-Halwagi, Mahmoud (committee member), Banerjee, Debjyoti (committee member).
Subjects/Keywords: ammonium nitrate; thermal decomposition; RSST; APTAC; additive
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APA (6th Edition):
Han, Z. (2016). Thermal Stability Studies of Ammonium Nitrate. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156911
Chicago Manual of Style (16th Edition):
Han, Zhe. “Thermal Stability Studies of Ammonium Nitrate.” 2016. Doctoral Dissertation, Texas A&M University. Accessed January 17, 2021.
http://hdl.handle.net/1969.1/156911.
MLA Handbook (7th Edition):
Han, Zhe. “Thermal Stability Studies of Ammonium Nitrate.” 2016. Web. 17 Jan 2021.
Vancouver:
Han Z. Thermal Stability Studies of Ammonium Nitrate. [Internet] [Doctoral dissertation]. Texas A&M University; 2016. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1969.1/156911.
Council of Science Editors:
Han Z. Thermal Stability Studies of Ammonium Nitrate. [Doctoral Dissertation]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/156911
Texas A&M University
10.
Landoll, Michael 1984-.
Ketone Production from the Thermal Decomposition of Carboxylate Salts.
Degree: PhD, Chemical Engineering, 2012, Texas A&M University
URL: http://hdl.handle.net/1969.1/148068
► The MixAlco process uses an anaerobic, mixed-culture fermentation to convert lignocellulosic biomass to carboxylate salts. The fermentation broth must be clarified so that only carboxylate…
(more)
▼ The MixAlco process uses an anaerobic, mixed-culture fermentation to convert lignocellulosic biomass to carboxylate salts. The fermentation broth must be clarified so that only carboxylate salts, water, and minimal impurities remain. Carboxylate salts are concentrated by evaporation and thermally decomposed into ketones. The ketones can then be chemically converted to a wide variety of chemicals and fuels.
The presence of excess lime in the
thermal decomposition step reduced product yield. Mixtures of calcium carboxylate salts were thermally decomposed at 450 degrees C. Low lime-to-salt ratios (g Ca(OH)2/g salt) of 0.00134 and less had a negligible effect on ketone yield. In contrast, salts with higher lime-to-salt ratios of 0.00461, 0.0190, and 0.272 showed 3.5, 4.6, and 9.4% loss in ketone yield, respectively. These losses were caused primarily by increases in tars and heavy oils; however, a three-fold increase in hydrocarbon production occurred as well. To predict ketone product distribution, a random-pairing and a Gibbs free energy minimization model were applied to
thermal decompositions of mixed calcium and sodium carboxylate salts. Random pairing appears to better predict ketone product composition.
For sodium and calcium acetate, two types of mixed sodium carboxylate salts, and two types of mixed calcium carboxylate salts, activation energy (EA) was determined using three isoconversional methods. For each salt type, EA varied significantly with conversion. The average EA for sodium and calcium acetate was 226.65 and 556.75 kJ/mol, respectively. The average EA for the two mixed sodium carboxylate salts were 195.61, and 218.18 kJ/mol. The average EA for the two mixed calcium carboxylate salts were 232.78, and 176.55 kJ/mol. In addition, three functions of conversion were employed to see which one best modeled the experimental data. The Sestak-Berggren model was the best overall. Possible reactor designs and configurations that address the challenges associated with the continuous
thermal decomposition of carboxylate salts are also presented and discussed.
Methods of fermentation broth clarification were tested. Flocculation showed little improvement in broth purity. Coagulation yielded broth of 93.23% purity. Filtration using pore sizes from 1 micrometer to 240 Daltons increased broth purity (90.79 to 98.33%) with decreasing pore size.
Advisors/Committee Members: Holtzapple, Mark T (advisor), El-Halwagi, Mahmoud (committee member), Glover, Charles (committee member), Capareda, Sergio (committee member).
Subjects/Keywords: MixAlco process; Ketone; Thermal decomposition; Carboxylate salt
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APA (6th Edition):
Landoll, M. 1. (2012). Ketone Production from the Thermal Decomposition of Carboxylate Salts. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/148068
Chicago Manual of Style (16th Edition):
Landoll, Michael 1984-. “Ketone Production from the Thermal Decomposition of Carboxylate Salts.” 2012. Doctoral Dissertation, Texas A&M University. Accessed January 17, 2021.
http://hdl.handle.net/1969.1/148068.
MLA Handbook (7th Edition):
Landoll, Michael 1984-. “Ketone Production from the Thermal Decomposition of Carboxylate Salts.” 2012. Web. 17 Jan 2021.
Vancouver:
Landoll M1. Ketone Production from the Thermal Decomposition of Carboxylate Salts. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1969.1/148068.
Council of Science Editors:
Landoll M1. Ketone Production from the Thermal Decomposition of Carboxylate Salts. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/148068
Penn State University
11.
Patidar, Lalit.
Thermal decomposition and combustion of RDX and HMX: Thermolysis experiments and molecular modeling.
Degree: 2020, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/17402lkp5147
► The cyclic compounds RDX and HMX are the most important nitramine energetic ingredients commonly used in many applications, including, among others, explosives and rocket propellants.…
(more)
▼ The cyclic compounds RDX and HMX are the most important nitramine energetic
ingredients commonly used in many applications, including, among others, explosives and rocket
propellants. In this work, a detailed reaction mechanism was developed for the
thermal
decomposition of nitramines RDX and HMX in the liquid phase using extensive quantum
mechanics calculations and important reaction pathways were discovered. The reaction mechanism
was further expanded by investigating the reactions of the intermediate species leading to the
formation of experimentally observed final
decomposition products.
The comprehensive mechanism was then validated for the case of HMX using synergetic
application of
thermal decomposition experiments and kinetic modeling. CH2O and N2O were
detected as the major
decomposition products at all heating rates considered in the TGA
(thermogravimetric analysis) experiments and all set temperatures considered in the CRT (confined
rapid thermolysis) experiments. Other
decomposition products that were detected and quantified
include H2O, NO2, NO, HCN, CO and CO2. A homogeneous liquid-phase reactor model was
developed to simulate the TGA and CRT experiments. Computational mass loss and species
evolution profiles were in reasonable agreement with the corresponding experimental results, thus
validating the comprehensive reaction mechanism. Based on a sensitivity analysis, important
reactions were identified that lead to the simultaneous formation of CH2O and N2O. Autocatalytic
prompt oxidation pathway via addition of HONO molecules due to the cage effect and hydrogen
abstraction via NO2 were found to be the dominant pathways for the
decomposition of HMX and
various intermediates species.
In addition to the liquid-phase mechanism, the gas phase
decomposition mechanism was
also updated based on a comparative ab-initio study by adding the early ring-opening and hydrogen abstraction reactions along with the reactions of species evolving from the liquid-phase
decomposition. G4(MP2) method was found to provide most accurate results for enthalpies of
formation of nitramine species when benchmarked against experimental data as well W1BD
method. For the calculations of reaction barrier heights using DFT, M06-2X functional was found
to provide accurate results when benchmarked against G4(MP2) method. Variational effects in the
transition state were found to be negligible and thermodynamic formulation of the conventional
transition state theory was used to calculate rate constants with improved tunneling corrections
using Eckart method.
Molecular parameters required for the calculations of transport properties during
combustion modeling were obtained using intermolecular potentials for various organic energetic
materials. Quantum mechanics calculations were used to parametrize analytical Buckingham
potentials which were then used to obtain Lennard-Jones collision parameters. Instead of choosing
a particular bath gas and a combining rule, a novel approach was proposed to obtain the selfinteraction Lennard-Jones…
Advisors/Committee Members: Stefan Thynell, Dissertation Advisor/Co-Advisor, Stefan Thynell, Committee Chair/Co-Chair, Richard A Yetter, Committee Member, Adrianus C Van Duin, Committee Member, Michael Matthew Micci, Outside Member, Daniel Connell Haworth, Program Head/Chair.
Subjects/Keywords: Energetic Materials; Thermal Decomposition; Combustion; Quantum mechanics
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APA (6th Edition):
Patidar, L. (2020). Thermal decomposition and combustion of RDX and HMX: Thermolysis experiments and molecular modeling. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/17402lkp5147
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Patidar, Lalit. “Thermal decomposition and combustion of RDX and HMX: Thermolysis experiments and molecular modeling.” 2020. Thesis, Penn State University. Accessed January 17, 2021.
https://submit-etda.libraries.psu.edu/catalog/17402lkp5147.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Patidar, Lalit. “Thermal decomposition and combustion of RDX and HMX: Thermolysis experiments and molecular modeling.” 2020. Web. 17 Jan 2021.
Vancouver:
Patidar L. Thermal decomposition and combustion of RDX and HMX: Thermolysis experiments and molecular modeling. [Internet] [Thesis]. Penn State University; 2020. [cited 2021 Jan 17].
Available from: https://submit-etda.libraries.psu.edu/catalog/17402lkp5147.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Patidar L. Thermal decomposition and combustion of RDX and HMX: Thermolysis experiments and molecular modeling. [Thesis]. Penn State University; 2020. Available from: https://submit-etda.libraries.psu.edu/catalog/17402lkp5147
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Newcastle
12.
Dharmarathne, Welayudage Nirmala Kumuduni.
Formation of toxic pollutants during the thermal decomposition and oxidation of cyclodiene pesticides.
Degree: PhD, 2019, University of Newcastle
URL: http://hdl.handle.net/1959.13/1395621
► Research Doctorate - Doctor of Philosophy (PhD)
This thesis provides an assessment of the toxic products formed during the thermal decomposition of the cyclodiene group…
(more)
▼ Research Doctorate - Doctor of Philosophy (PhD)
This thesis provides an assessment of the toxic products formed during the thermal decomposition of the cyclodiene group of pesticides and their main intermediate, under gas phase conditions. Cyclodiene pesticides, namely, dieldrin, aldrin, endosulfan and etc have widespread applications to control broad range of insects that spoil agricultural plantations. Thermal decompositions of the cyclodiene pesticides occurs in the fire that storage and processing facilities or in burning of biomass treated or contaminated with cyclodiene. The presence of six chlorine atoms in the molecule of cyclodiene indicates the propensity for releasing highly toxic chlorinated volatiles in combustion processes. We employed a bench type tubular reactor system to perform experiments, varying oxygen contents and temperatures. The analysis of the mechanism was assisted by the quantum chemical calculations, allowing us to propose mechanisms for the thermal decomposition of cyclodiene pesticides and their intermediates. The thermal decomposition of endosulfan (C9H6Cl6O3S) produces SO2, HCl, CO, 2,5-dihydrofuran and propene as gaseous compounds and the analysis of volatile organic compounds (VOC) identified hexachlorocyclopentadiene (HCCP), tetrachlorostyrene (TCS), pentachlorostyrene (PCS), pentachlorocyclopentadiene (PCCP), and all the range of mono to hexa chlorinated benzenes. Experimental and quantum chemical calculations indicated that the initial step of the pyrolysis of endosulfan started at 573 K, involving a retro-Diels-Alder elimination reaction which produces HCCP and 4,7-dihydro-1,3,2-dioxathiepine-2-oxide (2HDTO). At reaction temperatures of 663 K and above, fission of a Cl atom from HCCP results in the formation of endosulfan radical, which promotes further decomposition of endosulfan via a low barrier free radical pathway and arising secondary decomposition products including HCl, TCS, PCS, PCCP and polychlorinated benzenes. The oxidative decomposition of endosulfan generates substantially more PCDF than PCDD. The maximum emission factor of total PCDD/F observed at 923 K with 6% O2 content and corresponds to 64 ng TEQ–WHO2005/mg of endosulfan and a total dioxin concentration of 1131 ng/mg of endosulfan. The VOC analysis revealed that chlorinated benzenes (CBz) and chlorinated phenols (CPh) as a PCDD/F precursors. As indicated by the homologue distribution of PCDD/F, all the range of mono to octa chlorinated PCDD/F were detected in our measurements. Reducing the O2 concentration from to 1.03% causes a significant decrease in the rate of PCDD/F formation over all temperatures. Hexachlorocyclopentadiene (HCCP) is the chlorinated reagent which is a key intermediate in the production of cyclodiene pesticides via Diels-Alder addition with a substrate. The investigation of the pyrolysis of HCCP revealed the reaction is initiated by chlorine atom fission, forming the pentachlorocyclopentadienyl radical, two of which combine to form an energized bis-(pentachlorocyclopentadienyl), (S0).…
Advisors/Committee Members: University of Newcastle. Faculty of Engineering & Built Environment, School of Engineering.
Subjects/Keywords: cyclodiene pesticides; toxic pollutants; thermal decomposition; endosulfan
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APA (6th Edition):
Dharmarathne, W. N. K. (2019). Formation of toxic pollutants during the thermal decomposition and oxidation of cyclodiene pesticides. (Doctoral Dissertation). University of Newcastle. Retrieved from http://hdl.handle.net/1959.13/1395621
Chicago Manual of Style (16th Edition):
Dharmarathne, Welayudage Nirmala Kumuduni. “Formation of toxic pollutants during the thermal decomposition and oxidation of cyclodiene pesticides.” 2019. Doctoral Dissertation, University of Newcastle. Accessed January 17, 2021.
http://hdl.handle.net/1959.13/1395621.
MLA Handbook (7th Edition):
Dharmarathne, Welayudage Nirmala Kumuduni. “Formation of toxic pollutants during the thermal decomposition and oxidation of cyclodiene pesticides.” 2019. Web. 17 Jan 2021.
Vancouver:
Dharmarathne WNK. Formation of toxic pollutants during the thermal decomposition and oxidation of cyclodiene pesticides. [Internet] [Doctoral dissertation]. University of Newcastle; 2019. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1959.13/1395621.
Council of Science Editors:
Dharmarathne WNK. Formation of toxic pollutants during the thermal decomposition and oxidation of cyclodiene pesticides. [Doctoral Dissertation]. University of Newcastle; 2019. Available from: http://hdl.handle.net/1959.13/1395621
University of Colorado
13.
Vasiliou, AnGayle Konstance.
Thermochemical Conversion of Biomass: A Molecular Viewpoint.
Degree: PhD, Chemistry & Biochemistry, 2011, University of Colorado
URL: https://scholar.colorado.edu/chem_gradetds/53
► This dissertation describes experiments performed to study the thermal decomposition of biomass from a molecular viewpoint. The structure of biomass consists of three major…
(more)
▼ This dissertation describes experiments performed to study the
thermal decomposition of biomass from a molecular viewpoint. The structure of biomass consists of three major parts: cellulose, hemicellulose and lignin. Thermochemical conversion of biomass, specifically pyrolysis and gasification, yields a complex mixture of light gases, condensable vapors and aromatic tars. The goal for the gasification of biomass is to maximize the production of syngas (CO and H2 ) and minimize the production of aromatic tars. This thesis provides thermochemical information particularly related to cellulose
decomposition.
The current technology for the conversion of biomass to biofuels is hindered by the lack of fundamental knowledge concerning detailed mechanisms and kinetic parameters that govern the process. In order to approach this problem, this work provides such information for furan, furfural, acetaldehyde and propionaldehyde, known intermediates in the pyrolysis of cellulose.
The
thermal decomposition of the aforementioned biomass molecules was formed in a microtubular reactor with pressures of 75-100 torr and up to temperatures of 1700 K corresponding to residence times of roughly 30-100 μs in the heated reactor. The biomass molecules were entrained in the carrier gases He or Ar and passed through the reactor. The
thermal decomposition of the molecules occurs during transit through the heated reactor and products are cooled upon expansion into a vacuum chamber. The pyrolysis product beam was interrogated by three unique schemes: Photoionization Time of Flight Mass Spectroscopy (PIMS) using 10.5 eV light, Matrix Isolation Infrared (IR) Spectroscopy and PIMS using tunable iv vacuum ultraviolet (VUV) radiation at the chemical dynamics beamline of the Advanced Light Source located at Lawrence Berkley National Laboratory in Berkley, CA. Unlike previous studies of biomass
decomposition, these experiments were able to identify the initial pyrolysis products.
The first half of this thesis will deal with the
thermal decomposition pathways and kinetics of furan and furfural. Earlier G2(MP2) electronic structure calculations predicted that furan will thermally decompose to acetylene, ketene, carbon monoxide, and propyne at lower temperatures. At higher temperatures, these calculations forecast that propargyl radical could result. We see all these products as well as the formation of aromatic hydrocarbons at higher concentrations. This is the first study to show radicals present in biomass
decomposition.
Thermal decomposition of furfural generates furan and thus follows the same mechanistic pathways as described above.
The second half of this manuscript details the
thermal decomposition of acetaldehyde and three isotopologues CH3CDO, CD3CHO and CD3CDO as well as benzaldehyde. As
thermal decomposition products of CH3CHO, we have identified CH3 (PIMS), CO (IR, PIMS), H (PIMS), H2 (PIMS), CH2CO (IR, PIMS), CH2=CHOH (IR, PIMS) and HCCH (IR, PIMS). The mechanism for
decomposition of benzaldehyde is analogous to…
Advisors/Committee Members: Gayfree Barney Ellison, Veronica Bierbaum, John Daily.
Subjects/Keywords: biomass; decomposition; reactor; thermal; Physical Chemistry; Physics
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APA (6th Edition):
Vasiliou, A. K. (2011). Thermochemical Conversion of Biomass: A Molecular Viewpoint. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/chem_gradetds/53
Chicago Manual of Style (16th Edition):
Vasiliou, AnGayle Konstance. “Thermochemical Conversion of Biomass: A Molecular Viewpoint.” 2011. Doctoral Dissertation, University of Colorado. Accessed January 17, 2021.
https://scholar.colorado.edu/chem_gradetds/53.
MLA Handbook (7th Edition):
Vasiliou, AnGayle Konstance. “Thermochemical Conversion of Biomass: A Molecular Viewpoint.” 2011. Web. 17 Jan 2021.
Vancouver:
Vasiliou AK. Thermochemical Conversion of Biomass: A Molecular Viewpoint. [Internet] [Doctoral dissertation]. University of Colorado; 2011. [cited 2021 Jan 17].
Available from: https://scholar.colorado.edu/chem_gradetds/53.
Council of Science Editors:
Vasiliou AK. Thermochemical Conversion of Biomass: A Molecular Viewpoint. [Doctoral Dissertation]. University of Colorado; 2011. Available from: https://scholar.colorado.edu/chem_gradetds/53
14.
Jomaa, Ghassan.
Étude des dégagements gazeux survenant pendant la coulée de pièces d’Aluminium : Study of gas emissions occurring during the aluminium casting process.
Degree: Docteur es, Hydrologie et hydrogéologie quantitatives, 2014, Paris, ENMP
URL: http://www.theses.fr/2014ENMP0068
► La fabrication de pièces automobiles en aluminium des formes complexes telles que les culasses de moteur par le procédé de fonderie est effectuée par l'insertion…
(more)
▼ La fabrication de pièces automobiles en aluminium des formes complexes telles que les culasses de moteur par le procédé de fonderie est effectuée par l'insertion de noyaux en sable durci par des résines (liants) organiques dans un moule métallique et la coulée d'un métal en fusion dans ce moule. Sous l'effet de la température élevée du métal, les résines organiques se décomposent et produisent des dégagements gazeux qui altèrent la qualité des pièces à fabriquer. Jusque tout récemment, la maîtrise des dégagements gazeux survenant pendant le procédé du moulage était basée sur des essais expérimentaux. L'objet du présent travail est d'étudier les dégagements gazeux par simulation numérique. Pour ce faire, nous avons proposé plusieurs modèles numériques. Nous avons introduit un modèle cinétique pour la décomposition thermique des résines organiques. Nous avons développé un modèle général d'écoulements multiphasiques en milieux poreux en utilisant la méthode de prise de moyenne volumique. Quatre modèles de dégagements gazeux, représentant l'écoulement et le transport de gaz dans le noyau sous différents scénarios, sont donnés à partir du modèle général. Des modèles sont également développés pour décrire le couplage de transferts thermiques dans le moule et la pièce à fabriquer avec les dégagements gazeux dans le noyau. L'implémentation des différents modèles dans le logiciel libre OpenFOAM a permis d'obtenir un outil de simulation capable de simuler les dégagements gazeux sous différents scénarios et d'étudier l'impact de plusieurs facteurs tels que le type des résines, la forme de noyau, la perméabilité de sable sur l'évolution de la pression du gaz dans le noyau.
The manufacture of automotive aluminum parts with complex shapes such as cylinder heads of the engine by the casting process is carried out by the insertion of cores made with sand hardened using organic resins (binders) in a metal mold and pouring of molten metal in this mold. As a result of the high temperature of poured metal, organic resins undergo thermal decomposition (pyrolysis) and produce gases which impair the quality of the parts to be manufactured. Until recently, the study of gas emissions occurring during the casting process was based on experimental tests. The purpose of this work is to study the gas emissions by numerical simulation. To do this, we proposed several numerical models. We introduced a kinetic model for the thermal decomposition of organic resins. We have developed a general model of multiphase flow in porous media using the method of volume averaging. Four models of gas emissions representing flow and transport of gas in the core under different scenarios are given from the general model. Models are also developed to describe the coupling of the heat transfer in the mold and the casting with gas emissions in the sand core. The implementation of the various models in the free software OpenFOAM provides a simulation tool that allows to simulate gas emissions under different scenarios and to study the impact of several factors…
Advisors/Committee Members: Goblet, Patrick (thesis director), Coquelet, Christophe (thesis director).
Subjects/Keywords: Moulage; Noyaux en sable; Résines organiques; Décomposition thermique; Dégagements gazeux; Simulation numérique; Casting; Sand core; Organic resins; Thermal decomposition; Gas emissions; Numerical simulation; 620
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APA ·
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Manager
APA (6th Edition):
Jomaa, G. (2014). Étude des dégagements gazeux survenant pendant la coulée de pièces d’Aluminium : Study of gas emissions occurring during the aluminium casting process. (Doctoral Dissertation). Paris, ENMP. Retrieved from http://www.theses.fr/2014ENMP0068
Chicago Manual of Style (16th Edition):
Jomaa, Ghassan. “Étude des dégagements gazeux survenant pendant la coulée de pièces d’Aluminium : Study of gas emissions occurring during the aluminium casting process.” 2014. Doctoral Dissertation, Paris, ENMP. Accessed January 17, 2021.
http://www.theses.fr/2014ENMP0068.
MLA Handbook (7th Edition):
Jomaa, Ghassan. “Étude des dégagements gazeux survenant pendant la coulée de pièces d’Aluminium : Study of gas emissions occurring during the aluminium casting process.” 2014. Web. 17 Jan 2021.
Vancouver:
Jomaa G. Étude des dégagements gazeux survenant pendant la coulée de pièces d’Aluminium : Study of gas emissions occurring during the aluminium casting process. [Internet] [Doctoral dissertation]. Paris, ENMP; 2014. [cited 2021 Jan 17].
Available from: http://www.theses.fr/2014ENMP0068.
Council of Science Editors:
Jomaa G. Étude des dégagements gazeux survenant pendant la coulée de pièces d’Aluminium : Study of gas emissions occurring during the aluminium casting process. [Doctoral Dissertation]. Paris, ENMP; 2014. Available from: http://www.theses.fr/2014ENMP0068
Pontifical Catholic University of Rio de Janeiro
15.
PAULO CESAR MARQUES VIEIRA.
[en] CONSIDERATIONS ON THE DECOMPOSITION OF LINEAR
PROGRAMS.
Degree: 2009, Pontifical Catholic University of Rio de Janeiro
URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=14194
► [pt] Neste trabalho é feito um estudo teórico das três estratégias de coordenação que são usadas nos algoritmos de decomposição em programação matemática: Preços, quotas…
(more)
▼ [pt] Neste trabalho é feito um estudo teórico das três
estratégias de coordenação que são usadas nos algoritmos de
decomposição em programação matemática: Preços, quotas e mista. São
apresentadas as respectivas condições de coordenabilidade com uma
discussão sobre o problema da descentralização das decisões no caso
de programas lineares. O objetivo é mostrar que a coordenação mista
é a alternativa mais viável para se obter a descentralização das
decisões quando os subproblemas são lineares.
[en] This work presents a theoretical discussion about
the three coordination mechanisms used on decomposition algorithms
in mathematical programming: price-directive, resource-directive
and mixed mechanisms. The coordenability conditions are developed
around the decentralization of the decisions problem in linear
programs. The goal is to suggest the mixed mechanism as the best
way to get the decentralization whem the subproblems are linear
programs.
Advisors/Committee Members: PHILIPPE MAHEY.
Subjects/Keywords: [pt] DECOMPOSICAO; [en] DECOMPOSITION; [pt] PROGRAMAS LINEARES
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APA (6th Edition):
VIEIRA, P. C. M. (2009). [en] CONSIDERATIONS ON THE DECOMPOSITION OF LINEAR
PROGRAMS. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=14194
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
VIEIRA, PAULO CESAR MARQUES. “[en] CONSIDERATIONS ON THE DECOMPOSITION OF LINEAR
PROGRAMS.” 2009. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 17, 2021.
http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=14194.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
VIEIRA, PAULO CESAR MARQUES. “[en] CONSIDERATIONS ON THE DECOMPOSITION OF LINEAR
PROGRAMS.” 2009. Web. 17 Jan 2021.
Vancouver:
VIEIRA PCM. [en] CONSIDERATIONS ON THE DECOMPOSITION OF LINEAR
PROGRAMS. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2009. [cited 2021 Jan 17].
Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=14194.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
VIEIRA PCM. [en] CONSIDERATIONS ON THE DECOMPOSITION OF LINEAR
PROGRAMS. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2009. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=14194
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Windsor
16.
Jacko, Michael G.
Studies in the thermal decomposition of metallic alkyls.
Degree: PhD, Chemistry and Biochemistry, 1962, University of Windsor
URL: https://scholar.uwindsor.ca/etd/6033
Subjects/Keywords: ALKYLS; DECOMPOSITION; METALLIC; METALLIC ALKYLS; Metallic alkyls; STUDIES; THERMAL; THERMAL DECOMPOSITION; Thermal decomposition
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APA (6th Edition):
Jacko, M. G. (1962). Studies in the thermal decomposition of metallic alkyls. (Doctoral Dissertation). University of Windsor. Retrieved from https://scholar.uwindsor.ca/etd/6033
Chicago Manual of Style (16th Edition):
Jacko, Michael G. “Studies in the thermal decomposition of metallic alkyls.” 1962. Doctoral Dissertation, University of Windsor. Accessed January 17, 2021.
https://scholar.uwindsor.ca/etd/6033.
MLA Handbook (7th Edition):
Jacko, Michael G. “Studies in the thermal decomposition of metallic alkyls.” 1962. Web. 17 Jan 2021.
Vancouver:
Jacko MG. Studies in the thermal decomposition of metallic alkyls. [Internet] [Doctoral dissertation]. University of Windsor; 1962. [cited 2021 Jan 17].
Available from: https://scholar.uwindsor.ca/etd/6033.
Council of Science Editors:
Jacko MG. Studies in the thermal decomposition of metallic alkyls. [Doctoral Dissertation]. University of Windsor; 1962. Available from: https://scholar.uwindsor.ca/etd/6033
University of Michigan
17.
Hall, John Herbert.
The Thermal Decomposition Of Aryl Azides.
Degree: PhD, Pure Sciences, 1959, University of Michigan
URL: http://hdl.handle.net/2027.42/127228
Subjects/Keywords: Aryl; Azides; Decomposition; Thermal
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Manager
APA (6th Edition):
Hall, J. H. (1959). The Thermal Decomposition Of Aryl Azides. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/127228
Chicago Manual of Style (16th Edition):
Hall, John Herbert. “The Thermal Decomposition Of Aryl Azides.” 1959. Doctoral Dissertation, University of Michigan. Accessed January 17, 2021.
http://hdl.handle.net/2027.42/127228.
MLA Handbook (7th Edition):
Hall, John Herbert. “The Thermal Decomposition Of Aryl Azides.” 1959. Web. 17 Jan 2021.
Vancouver:
Hall JH. The Thermal Decomposition Of Aryl Azides. [Internet] [Doctoral dissertation]. University of Michigan; 1959. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/2027.42/127228.
Council of Science Editors:
Hall JH. The Thermal Decomposition Of Aryl Azides. [Doctoral Dissertation]. University of Michigan; 1959. Available from: http://hdl.handle.net/2027.42/127228
Anna University
18.
Marx Nirmal R.
Studies on pure and Zn and Mn doped nanocrystalline CdS
prepared by thermal decomposition using single source molecular
precursors;.
Degree: 2014, Anna University
URL: http://shodhganga.inflibnet.ac.in/handle/10603/14546
► Semiconductors with reduced dimension present a large variety of new interesting properties in comparison to the bulk material and open new ways in the engineering…
(more)
▼ Semiconductors with reduced dimension present a
large variety of new interesting properties in comparison to the
bulk material and open new ways in the engineering of
semiconductors. The electronic and optical properties of II-VI
group semiconductor nanoparticles have been extensively
investigated in view of a wide variety of applications. Among the
semiconductors, CdS is one of the most important wide band gap
semiconductors, which has been extensively studied due to its
ability to tune emission in the visible region simply by changing
its size or shape. Cadmium pyrrolidine dithiocarbamate (Cd(pdtc)2)
is one of the interesting metal complexes for the single source
precursor synthesis of CdS by thermal decomposition at 150 °C in
the presence of HDA which acts as solvent as well as capping agent.
Two different morphologies such as spherical and rod shaped
nanostructures were obtained with microwave and conventional
heating process respectively. HRTEM results show the formation
spherical and rod shaped nanoparticles in different heating
processes. The calculated values of - ln (Ct/C0) (degradation rate)
are approximately linear with the irradiation time t. Hence, the
photocatalytic degradation reactions of rhodamine B are following
the first-order kinetics. The apparent rate constants were obtained
from the relation Kt = ln (C0/Ct) for all nanoparticles using the
slope of ln (C0/Ct) versus degradation time graph. The Zn doped CdS
nanoparticles enhance the overall degradation rate with respect to
the pure and Mn doped CdS nanoparticles. The effect of dopant
concentration on the degradation of the dye is also observed for
the case of Zn and Mn doped CdS systems. The apparent rate constant
value K is calculated for all samples, which increase with
increasing the concentration of Mn and Zn. newline newline
newline
Advisors/Committee Members: Sivakumar, K..
Subjects/Keywords: Nanocrystalline; thermal; decomposition; molecular
precursors; Cadmium pyrrolidine dithiocarbamate
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APA (6th Edition):
R, M. N. (2014). Studies on pure and Zn and Mn doped nanocrystalline CdS
prepared by thermal decomposition using single source molecular
precursors;. (Thesis). Anna University. Retrieved from http://shodhganga.inflibnet.ac.in/handle/10603/14546
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
R, Marx Nirmal. “Studies on pure and Zn and Mn doped nanocrystalline CdS
prepared by thermal decomposition using single source molecular
precursors;.” 2014. Thesis, Anna University. Accessed January 17, 2021.
http://shodhganga.inflibnet.ac.in/handle/10603/14546.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
R, Marx Nirmal. “Studies on pure and Zn and Mn doped nanocrystalline CdS
prepared by thermal decomposition using single source molecular
precursors;.” 2014. Web. 17 Jan 2021.
Vancouver:
R MN. Studies on pure and Zn and Mn doped nanocrystalline CdS
prepared by thermal decomposition using single source molecular
precursors;. [Internet] [Thesis]. Anna University; 2014. [cited 2021 Jan 17].
Available from: http://shodhganga.inflibnet.ac.in/handle/10603/14546.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
R MN. Studies on pure and Zn and Mn doped nanocrystalline CdS
prepared by thermal decomposition using single source molecular
precursors;. [Thesis]. Anna University; 2014. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/14546
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Anna University
19.
Rajasekhar Reddy, G.
Green synthesis characterization and biomedical
applications of silver and gold nanoparticles; -.
Degree: Chemical Engineering, 2013, Anna University
URL: http://shodhganga.inflibnet.ac.in/handle/10603/25097
► The synthesis and characterization of nanomaterials by using plant newlineextracts is an emerging field of nanotechnology with an extensive newlineapplications in the fields of physics…
(more)
▼ The synthesis and characterization of nanomaterials
by using plant newlineextracts is an emerging field of
nanotechnology with an extensive newlineapplications in the fields
of physics chemistry biology and medicine With newlinethe
development of several chemical synthesis techniques the concern
for newlineenvironmental contamination is also heightened as the
chemical synthesis newlineprotocols need some toxic chemicals for
synthesis Integrative conventional newlinebiotechnology and hybrid
nanotechnology lead to nano biotechnology which newlineutilizes
original concepts and natural materials for manufacturing nanoscale
newlinedevices under the control of green chemistry principles In
general living newlineorganisms traditionally represent a good
model for engineers to learn from newlinebiological constituents
with the optimal functionality of our interests having newlinebeen
used in the creation of nano biotechnology products Synthesis of
newlinemetallic nanoparticles by using plant extracts is an
attractive one particularly newlineat medicinal applications
because of advantage of certain properties such as
newlinebiodegradability environmental friendly high
biocompatibility with low newlinetoxicity when compared with
conventional synthesis methods newlineThe present study is one such
attempt with a novel green approach newlinefor the synthesis
characterization biomedical applications and thermal
newlinedecomposition studies of silver and gold nanoparticles using
Senna siamea newlineplant seed aqueous extract under ambient
conditions An extensive qualitative newlineand quantitative
comparisons of the plant mediated synthesized nanoparticles
newlinebetween the different plants were measured The reaction
mixture turned newlinebrownish gray color for silver nanoparticles
and violet for gold nanoparticles newlineafter 3 hours of
incubation period Obtained nanoparticles were confirmed by
newlinesurface plasmon spectra using UVvis spectrophotometer around
470 nm for newlinesilver and 520 nm for gold nanoparticles
newlineFourier Transform Infrared Spectroscopy FTIR study confirmed
newlinethat the synthesized nanoparticles were reduced and capped
by the plant seed newlinechemicals only both silver and gold
newlinen
-
Advisors/Committee Members: Nagendra Gandhi, N.
Subjects/Keywords: biocompatibility; Biomedical Applications; Green Synthesis; Nanoparticles; thermal decomposition
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CSE |
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APA (6th Edition):
Rajasekhar Reddy, G. (2013). Green synthesis characterization and biomedical
applications of silver and gold nanoparticles; -. (Thesis). Anna University. Retrieved from http://shodhganga.inflibnet.ac.in/handle/10603/25097
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Rajasekhar Reddy, G. “Green synthesis characterization and biomedical
applications of silver and gold nanoparticles; -.” 2013. Thesis, Anna University. Accessed January 17, 2021.
http://shodhganga.inflibnet.ac.in/handle/10603/25097.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Rajasekhar Reddy, G. “Green synthesis characterization and biomedical
applications of silver and gold nanoparticles; -.” 2013. Web. 17 Jan 2021.
Vancouver:
Rajasekhar Reddy G. Green synthesis characterization and biomedical
applications of silver and gold nanoparticles; -. [Internet] [Thesis]. Anna University; 2013. [cited 2021 Jan 17].
Available from: http://shodhganga.inflibnet.ac.in/handle/10603/25097.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Rajasekhar Reddy G. Green synthesis characterization and biomedical
applications of silver and gold nanoparticles; -. [Thesis]. Anna University; 2013. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/25097
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Texas A&M University
20.
Zhang, Chuanji.
Thermal decomposition study of hydroxylamine nitrate during storage and handling.
Degree: MS, Chemical Engineering, 2007, Texas A&M University
URL: http://hdl.handle.net/1969.1/5935
► Hydroxylamine nitrate (HAN), an important agent for the nuclear industry and the U.S. Army, has been involved in several costly incidents. To prevent similar incidents,…
(more)
▼ Hydroxylamine nitrate (HAN), an important agent for the nuclear industry
and the U.S. Army, has been involved in several costly incidents. To prevent similar
incidents, the study of HAN safe storage and handling boundary has become
extremely important for industries. However, HAN
decomposition involves
complicated reaction pathways due to its autocatalytic behavior and therefore
presents a challenge for definition of safe boundaries of HAN storage and handling.
This research focused on HAN
decomposition behavior under various conditions and
proposed isothermal aging testing and kinetic-based simulation to determine safety
boundaries for HAN storage and handling.
Specifically, HAN
decomposition in the presence of glass, titanium, stainless
steel with titanium, or stainless steel was examined in an Automatic Pressure
Tracking Adiabatic Calorimeter (APTAC). n-th order kinetics was used for initial
reaction rate estimation. Because stainless steel is a commonly used material for
HAN containers, isothermal aging tests were conducted in a stainless steel cell to determine the maximum safe storage time of HAN. Moreover, by changing
thermal
inertia, data for HAN
decomposition in the stainless steel cell were examined and the
experimental results were simulated by the
Thermal Safety Software package.
This work offers useful guidance for industries that manufacture, handle, and
store HAN. The experimental data acquired not only can help with aspects of process
safety design, including emergency relief systems, process control, and process
equipment selection, but also is a useful reference for the associated theoretical study
of autocatalytic
decomposition behavior.
Advisors/Committee Members: Mannan, M. Sam (advisor), Banerjee, Debjyoti (committee member), Hall, Kenneth R. (committee member).
Subjects/Keywords: Thermal decomposition; Hydroxylamine nitrate; APTAC
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APA (6th Edition):
Zhang, C. (2007). Thermal decomposition study of hydroxylamine nitrate during storage and handling. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/5935
Chicago Manual of Style (16th Edition):
Zhang, Chuanji. “Thermal decomposition study of hydroxylamine nitrate during storage and handling.” 2007. Masters Thesis, Texas A&M University. Accessed January 17, 2021.
http://hdl.handle.net/1969.1/5935.
MLA Handbook (7th Edition):
Zhang, Chuanji. “Thermal decomposition study of hydroxylamine nitrate during storage and handling.” 2007. Web. 17 Jan 2021.
Vancouver:
Zhang C. Thermal decomposition study of hydroxylamine nitrate during storage and handling. [Internet] [Masters thesis]. Texas A&M University; 2007. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1969.1/5935.
Council of Science Editors:
Zhang C. Thermal decomposition study of hydroxylamine nitrate during storage and handling. [Masters Thesis]. Texas A&M University; 2007. Available from: http://hdl.handle.net/1969.1/5935
University of Newcastle
21.
Hou, Song.
Thermal studies of chlorinated and mixed halogenated biphenyls.
Degree: PhD, 2015, University of Newcastle
URL: http://hdl.handle.net/1959.13/1310326
► Research Doctorate - Doctor of Philosophy (PhD)
This thesis provides an assessment of the toxic pollutants formed during the thermal decomposition of polychlorinated (PCBs) and…
(more)
▼ Research Doctorate - Doctor of Philosophy (PhD)
This thesis provides an assessment of the toxic pollutants formed during the thermal decomposition of polychlorinated (PCBs) and mixed halogenated (i.e., simultaneously chlorinated and brominated) biphenyls (PXBs; X = Cl/Br), under gas phase conditions similar to those occurring in fires, and in other combustion processes. (For convenience, in this thesis, the term polychlorinated biphenyls also comprises monochlorinated biphenyls.) In particular, we have investigated the oxidation of 4-chlorobiphenyl (4-CB), 4,4’-dichlorobiphenyl (4,4’-DCB) and 4-bromo,4’-chlorobiphenyl (4,4’-BCB), at temperatures lower than those leading to complete conversion of PCBs and PXBs to HBr, HCl, H2O and CO2. The presence of chlorine and bromine in the molecules indicates the propensity for releasing highly toxic chlorinated and mixed halogenated volatiles (VOCs) in combustion processes. In addition, previous studies reported polychlorinated biphenyls, which were widely used as transformer oil in capacitors, to form polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs). The work covered by this thesis was designed to examine the type and abundance of pollutants formed in incomplete oxidation of PCBs and PXBs and to gain an understanding into the effect of structural differences among the reactants on the reaction mechanisms responsible for the formation of pollutants. In addition, we examined the effect of three materials of construction of the reactors: alumina (99.5 %), quartz (99.95 %) and quartz with boron-oxide coating on the reactor walls. Initially, we studied the same reactant (4-CB) in the three reactors, to understand the effect of impurities (trace amount of transition metals) and surface generated singlet oxygen on the reaction mechanisms responsible for the pollutant formation. We established a laboratory-scale apparatus that consisted of a laminar flow reactor equipped with a sampling system for intercepting the volatile and condensable products. A XAD-2 cartridge served to trap the volatile organic compounds (VOCs) and PCDD/Fs. The analysis of VOCs involved high resolution gas chromatography – quadrupole mass spectrometry (GC-QMS) while HRGC – ion trap MS (GC-ITMS) quantitated the PCDD/Fs produced. The development of reaction mechanisms involved the application of Gaussian 09 suite of programs. We optimised structures and calculated the zero point vibrational energies (ZPVE) at the B3LYP/6-31G(d), B3LYP/6-311G(d,p) and M062X/6-311+G(d,p) levels of theory. Stationary points located were either minima or transition states (TSs) determined by vibrational frequency analysis wherein a transition structure contained just one imaginary frequency along the specified reaction coordinates. Intrinsic reaction coordinate (IRC) analysis afforded linking the reactants and products with their TSs. The thermal decomposition of 4-CB in the alumina reactor produces a number of volatile pollutants, including chlorophenols and chlorobenzenes, which are important…
Advisors/Committee Members: University of Newcastle. Faculty of Engineering & Built Environment, School of Engineering.
Subjects/Keywords: PCDD/Fs; VOCs; PCBs; thermal decomposition; thesis by publication
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Manager
APA (6th Edition):
Hou, S. (2015). Thermal studies of chlorinated and mixed halogenated biphenyls. (Doctoral Dissertation). University of Newcastle. Retrieved from http://hdl.handle.net/1959.13/1310326
Chicago Manual of Style (16th Edition):
Hou, Song. “Thermal studies of chlorinated and mixed halogenated biphenyls.” 2015. Doctoral Dissertation, University of Newcastle. Accessed January 17, 2021.
http://hdl.handle.net/1959.13/1310326.
MLA Handbook (7th Edition):
Hou, Song. “Thermal studies of chlorinated and mixed halogenated biphenyls.” 2015. Web. 17 Jan 2021.
Vancouver:
Hou S. Thermal studies of chlorinated and mixed halogenated biphenyls. [Internet] [Doctoral dissertation]. University of Newcastle; 2015. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1959.13/1310326.
Council of Science Editors:
Hou S. Thermal studies of chlorinated and mixed halogenated biphenyls. [Doctoral Dissertation]. University of Newcastle; 2015. Available from: http://hdl.handle.net/1959.13/1310326
University of Colorado
22.
Urness, Kimberly Noelle.
A Molecular Picture of Biofuel Decomposition: Pyrolysis of Furan and Select Furanics.
Degree: PhD, Mechanical Engineering, 2014, University of Colorado
URL: https://scholar.colorado.edu/mcen_gradetds/1
► Limited fossil fuel resources and climate impacts due to carbon dioxide emissions have made it critical that we use renewable, carbon-neutral fuels. Biomass, in…
(more)
▼ Limited fossil fuel resources and climate impacts due to carbon dioxide emissions have made it critical that we use renewable, carbon-neutral fuels. Biomass, in the form of crop waste or the inedible portion of plants, has the potential to be a renewable and economical source of energy. Recent developments in the conversion of lignocellulosic biomass have sparked an interest in the production of biofuels and valuable platform chemicals, synthesizing molecules such as alkylated furans, furanic ethers, and various lactones. Early studies indicate that many of these potential furanic and lactonic fuels have similar properties to gasoline or diesel, however, little is known about their pyrolytic and combustion behavior.
In order to establish a molecular picture of the first
thermal products formed from the pyrolysis and oxidation of furanic biofuels, a microtubular flow reactor was used to thermally decompose furan, 2-methoxyfuran, and select lactones. Dilute samples of these molecules were entrained in He or Ar and thermally cracked in a heated silicon carbide microreactor. Products, including radicals and metastables formed at early pyrolysis times (50−200
μs), were detected by 118.2 nm (10.487 eV) photoionization mass spectrometry (PIMS), tunable synchrotron vacuum ultraviolet PIMS and Ar matrix infrared spectroscopy. As most initiation rates need to be calculated because they are too difficult to measure, the experimental results presented in this thesis demonstrate progress towards validating these calculations, aiding in the development of accurate initiation chemistry for kinetic mechanisms.
The published mechanism for pyrolysis of furan (C
4H
4O), the parent compound of the more complicated furans described above, involves
decomposition via a pair of carbenes. The product branching ratio of this reaction was measured over a range of temperatures and compared to predictions of three published furan kinetic mechanisms. A higher-energy radical channel that produces propargyl radical (HCCCH
2) and H-atom was also detected and quantified.
The unimolecular and low-pressure bimolecular
decomposition mechanisms of the simplest furanic ether, 2-methoxyfuran, were also studied. Recent electronic structure calculations indicate this substituted furan has an unusually weak O−CH
3 bond, which results in bond scission and the production of CH
3 and 2-furanyloxy radicals. The final products detected from the ring opening of 2-furanyloxy radical include 2 CO, HCCH and H. Secondary products resulting from H or CH
3 addition to the parent and radical reactions with 2-furanyloxy were also detected and include CH
2=CH-CHO, CH
3-CH=CH-CHO, CH
3-COCH= CH
2 and furanones. In addition to detection and quantification of the primary pyrolysis products, this work also includes the first experimental characterization of 2-furanyloxy radical by the assignment of several vibrational bands in an Ar…
Advisors/Committee Members: John W. Daily, G. Barney Ellison, Veronica M. Bierbaum.
Subjects/Keywords: biofuels; furanics; pyrolysis; thermal decomposition; Chemistry; Mechanical Engineering
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APA (6th Edition):
Urness, K. N. (2014). A Molecular Picture of Biofuel Decomposition: Pyrolysis of Furan and Select Furanics. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/mcen_gradetds/1
Chicago Manual of Style (16th Edition):
Urness, Kimberly Noelle. “A Molecular Picture of Biofuel Decomposition: Pyrolysis of Furan and Select Furanics.” 2014. Doctoral Dissertation, University of Colorado. Accessed January 17, 2021.
https://scholar.colorado.edu/mcen_gradetds/1.
MLA Handbook (7th Edition):
Urness, Kimberly Noelle. “A Molecular Picture of Biofuel Decomposition: Pyrolysis of Furan and Select Furanics.” 2014. Web. 17 Jan 2021.
Vancouver:
Urness KN. A Molecular Picture of Biofuel Decomposition: Pyrolysis of Furan and Select Furanics. [Internet] [Doctoral dissertation]. University of Colorado; 2014. [cited 2021 Jan 17].
Available from: https://scholar.colorado.edu/mcen_gradetds/1.
Council of Science Editors:
Urness KN. A Molecular Picture of Biofuel Decomposition: Pyrolysis of Furan and Select Furanics. [Doctoral Dissertation]. University of Colorado; 2014. Available from: https://scholar.colorado.edu/mcen_gradetds/1
University of Colorado
23.
Porterfield, Jessica Paige.
The Thermal Decomposition of Biofuels in a Heated Micro-Reactor: Ketones, Carbohydrates, and Esters.
Degree: PhD, Chemistry & Biochemistry, 2016, University of Colorado
URL: https://scholar.colorado.edu/chem_gradetds/200
► This thesis describes the thermal, unimolecular decomposition pathways of the following potential biofuels: cyclohexanone (C6H10=O), glycolaldehyde (HCOCH2OH), methyl acetate (CH3COOCH3), and methyl butanoate (CH3CH2CH2COOCH3)…
(more)
▼ This thesis describes the
thermal, unimolecular
decomposition pathways of the following potential biofuels: cyclohexanone (C
6H
10=O), glycolaldehyde (HCOCH
2OH), methyl acetate (CH
3COOCH
3), and methyl butanoate (CH
3CH
2CH
2COOCH
3) as well as many products of their
decomposition. These fuels have been diluted in a buffer gas (less than 0.1% in He, Ne, Ar, or Kr) and decomposed in a heated micro-reactor. The micro-reactor is a resistively heated silicon carbide (SiC) tube that can be heated to temperatures of up to 1800 K; it is 2 - 3 cm long and 0.6 to 1 mm in diameter. Residence times in the tiny reactor are roughly 25 - 150 microseconds. As the gas mixture exits the reactor, it expands supersonically into a vacuum chamber (1 x 10
−6 Torr), which effectively quenches any further chemistry. Mass data of the products are provided by both tunable synchrotron photoionization mass spectrometry (PIMS) conducted at Lawrence Berkeley National Laboratory’s Advanced Light Source, and by pulsed, 10.487 eV PIMS conducted at the University of Colorado. Vibrational spectra are collected utilizing matrix isolation infrared spectroscopy (IR). Attempts to validate computational results of pressure within the reactor are also discussed, in which X-ray fluorescence studies were conducted inside the reactor using Kr as a fluorescent tag. With internal temperature and pressure characterized, the micro-reactor will also be a useful tool in determining rate constants of
decomposition reactions. The complementary diagnostics of PIMS and IR detect all of the atoms, metastables, and radicals that results from pyrolysis of these fuels. Chemical
decomposition pathways are then constructed to justify the observed product distribution.
Advisors/Committee Members: Jessica P. Porterfield, G. Barney. Ellison, Mark R. Nimlos, John W. Daily, Veronica M. Bierbaum.
Subjects/Keywords: Biofuels; Carbohydrates; Decomposition; Esters; Ketones; Thermal; Physical Chemistry
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Export
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APA (6th Edition):
Porterfield, J. P. (2016). The Thermal Decomposition of Biofuels in a Heated Micro-Reactor: Ketones, Carbohydrates, and Esters. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/chem_gradetds/200
Chicago Manual of Style (16th Edition):
Porterfield, Jessica Paige. “The Thermal Decomposition of Biofuels in a Heated Micro-Reactor: Ketones, Carbohydrates, and Esters.” 2016. Doctoral Dissertation, University of Colorado. Accessed January 17, 2021.
https://scholar.colorado.edu/chem_gradetds/200.
MLA Handbook (7th Edition):
Porterfield, Jessica Paige. “The Thermal Decomposition of Biofuels in a Heated Micro-Reactor: Ketones, Carbohydrates, and Esters.” 2016. Web. 17 Jan 2021.
Vancouver:
Porterfield JP. The Thermal Decomposition of Biofuels in a Heated Micro-Reactor: Ketones, Carbohydrates, and Esters. [Internet] [Doctoral dissertation]. University of Colorado; 2016. [cited 2021 Jan 17].
Available from: https://scholar.colorado.edu/chem_gradetds/200.
Council of Science Editors:
Porterfield JP. The Thermal Decomposition of Biofuels in a Heated Micro-Reactor: Ketones, Carbohydrates, and Esters. [Doctoral Dissertation]. University of Colorado; 2016. Available from: https://scholar.colorado.edu/chem_gradetds/200
Missouri University of Science and Technology
24.
Peaslee, David Edward.
Characterization of nano-scaled metal-hydrides confined in nano-porous carbon frameworks.
Degree: PhD, Physics, Missouri University of Science and Technology
URL: https://scholarsmine.mst.edu/doctoral_dissertations/1831
► "Metal hydrides are currently being studied to provide hydrogen for use in fuel cells and for transportation applications. Hydrogen can be stored in chemical compounds…
(more)
▼ "Metal hydrides are currently being studied to provide hydrogen for use in fuel cells and for transportation applications. Hydrogen can be stored in chemical compounds at higher density and lower volume than liquid H₂ or compressed gas. Thermodynamic properties of metal hydrides differ between bulk and nano-sized particles. Many metal hydrides with useful volumetric and gravimetric capacities have high decomposition temperatures, but when placed in nano-sized frameworks (or templates) desorption and adsorption temperatures can be fine-tuned to meet engineering requirements for real-world systems. Additionally, some metal hydrides have shown a change in the decomposition pathway when infiltrated into these frameworks, thereby reducing the amount of unwanted byproducts, and potentially improving the cyclability of the material. The Temperature Programmed Decomposition Mass Spectrum Residual Gas Analyzer can be used to characterize gas desorption, decomposition temperatures, picogram changes in mass, and ionization energies for a variety of materials and gasses. The goal of the system is to characterize desorption of the hydrogen (including byproduct gasses) and the decomposition of the metal hydrides. The experimental apparatus is composed of four main components: the residual gas analyzer (RGA), the low temperature stage quartz crystal microbalance (QCM), the high temperature heating stage, and two vacuum chambers separated by a small flow hole which allows a direct line-of-site to the RGA" – Abstract, page iv.
Subjects/Keywords: Nanoconfinement; Thermal Decomposition; Physics
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Export
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APA (6th Edition):
Peaslee, D. E. (n.d.). Characterization of nano-scaled metal-hydrides confined in nano-porous carbon frameworks. (Doctoral Dissertation). Missouri University of Science and Technology. Retrieved from https://scholarsmine.mst.edu/doctoral_dissertations/1831
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Chicago Manual of Style (16th Edition):
Peaslee, David Edward. “Characterization of nano-scaled metal-hydrides confined in nano-porous carbon frameworks.” Doctoral Dissertation, Missouri University of Science and Technology. Accessed January 17, 2021.
https://scholarsmine.mst.edu/doctoral_dissertations/1831.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
MLA Handbook (7th Edition):
Peaslee, David Edward. “Characterization of nano-scaled metal-hydrides confined in nano-porous carbon frameworks.” Web. 17 Jan 2021.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Vancouver:
Peaslee DE. Characterization of nano-scaled metal-hydrides confined in nano-porous carbon frameworks. [Internet] [Doctoral dissertation]. Missouri University of Science and Technology; [cited 2021 Jan 17].
Available from: https://scholarsmine.mst.edu/doctoral_dissertations/1831.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Council of Science Editors:
Peaslee DE. Characterization of nano-scaled metal-hydrides confined in nano-porous carbon frameworks. [Doctoral Dissertation]. Missouri University of Science and Technology; Available from: https://scholarsmine.mst.edu/doctoral_dissertations/1831
Note: this citation may be lacking information needed for this citation format:
No year of publication.
University of Windsor
25.
Webster, N. J.
Thermal decomposition of lead tetramethyl.
Degree: MS, Chemistry and Biochemistry, 1969, University of Windsor
URL: https://scholar.uwindsor.ca/etd/6879
Subjects/Keywords: DECOMPOSITION; LEAD; TETRAMETHYL; THERMAL
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APA (6th Edition):
Webster, N. J. (1969). Thermal decomposition of lead tetramethyl. (Masters Thesis). University of Windsor. Retrieved from https://scholar.uwindsor.ca/etd/6879
Chicago Manual of Style (16th Edition):
Webster, N J. “Thermal decomposition of lead tetramethyl.” 1969. Masters Thesis, University of Windsor. Accessed January 17, 2021.
https://scholar.uwindsor.ca/etd/6879.
MLA Handbook (7th Edition):
Webster, N J. “Thermal decomposition of lead tetramethyl.” 1969. Web. 17 Jan 2021.
Vancouver:
Webster NJ. Thermal decomposition of lead tetramethyl. [Internet] [Masters thesis]. University of Windsor; 1969. [cited 2021 Jan 17].
Available from: https://scholar.uwindsor.ca/etd/6879.
Council of Science Editors:
Webster NJ. Thermal decomposition of lead tetramethyl. [Masters Thesis]. University of Windsor; 1969. Available from: https://scholar.uwindsor.ca/etd/6879
Georgia Tech
26.
Boatright, David L.
Kinetic and mechanistic studies of the thermal decomposition of glycolate and N-Nitrosoiminodiacetic acid in aqueous basic salt solutions :
II Phase transfer catalysis in supercritical fluids.
Degree: PhD, Chemistry and biochemistry, 1995, Georgia Tech
URL: http://hdl.handle.net/1853/29885
Subjects/Keywords: Materials Thermal properties; Decomposition (Chemistry)
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APA (6th Edition):
Boatright, D. L. (1995). Kinetic and mechanistic studies of the thermal decomposition of glycolate and N-Nitrosoiminodiacetic acid in aqueous basic salt solutions :
II Phase transfer catalysis in supercritical fluids. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/29885
Chicago Manual of Style (16th Edition):
Boatright, David L. “Kinetic and mechanistic studies of the thermal decomposition of glycolate and N-Nitrosoiminodiacetic acid in aqueous basic salt solutions :
II Phase transfer catalysis in supercritical fluids.” 1995. Doctoral Dissertation, Georgia Tech. Accessed January 17, 2021.
http://hdl.handle.net/1853/29885.
MLA Handbook (7th Edition):
Boatright, David L. “Kinetic and mechanistic studies of the thermal decomposition of glycolate and N-Nitrosoiminodiacetic acid in aqueous basic salt solutions :
II Phase transfer catalysis in supercritical fluids.” 1995. Web. 17 Jan 2021.
Vancouver:
Boatright DL. Kinetic and mechanistic studies of the thermal decomposition of glycolate and N-Nitrosoiminodiacetic acid in aqueous basic salt solutions :
II Phase transfer catalysis in supercritical fluids. [Internet] [Doctoral dissertation]. Georgia Tech; 1995. [cited 2021 Jan 17].
Available from: http://hdl.handle.net/1853/29885.
Council of Science Editors:
Boatright DL. Kinetic and mechanistic studies of the thermal decomposition of glycolate and N-Nitrosoiminodiacetic acid in aqueous basic salt solutions :
II Phase transfer catalysis in supercritical fluids. [Doctoral Dissertation]. Georgia Tech; 1995. Available from: http://hdl.handle.net/1853/29885
Indian Institute of Science
27.
Chakravarty, Harish Kumar.
Thermal Decomposition Of Haloethanols And Ignition Of JP-10.
Degree: PhD, Faculty of Science, 2013, Indian Institute of Science
URL: http://etd.iisc.ac.in/handle/2005/2109
► In this thesis, the thermal decomposition investigation of haloethanols namely 2-chloroethanol and 2-bromoethanol are reported both experimental and theoretical. Computational calculation of enthalpy of formation…
(more)
▼ In this thesis, the
thermal decomposition investigation of haloethanols namely 2-chloroethanol and 2-bromoethanol are reported both experimental and theoretical. Computational calculation of enthalpy of formation haloethanols using isodesmic and atomization reactions has also been reported. Finally, the chemistry of JP-10 ignition has also been investigated using shock tube.
Chapter 1 gives a brief introduction to the experimental shock tube technique. Brief surveys of literature pertinent to haloethanols and JP-10 have also been discussed. The importance of
thermal rate coefficient and detection techniques in shock tube chemistry is presented. Details of the theoretical methods used in the determination of
thermal rate coefficients have been described at the end of the chapter.
In Chapter 2, I have discussed experimental methods used in carrying out this work. The details of the experimental shock tube set-up employed in this work have been elaborated in this chapter. Kinetic simulations performed to understand the mechanism of chemical transformation of haloethanols at high temperature have also been presented.
In chapter 3,
thermal decomposition results obtained for 2-chloroethanol have been described. The kinetic data have been obtained in the temperature range of 930-1100 K behind the reflected shock wave in a shock tube. Analyses of pre and post shock mixture using FT-IR and gas chromatographic techniques are presented. Chemical kinetic simulation performed to simulate the product distribution is presented. The reduced kinetic model has also been presented which was obtained using the sensitivity analysis and was validated by comparison to the shock tube measurements. The details of the β-substitution effect have been shown. The kinetic parameters of the unimolecular elimination of HCl and H2O have been presented both experimentally and theoretically. Theoretical results were obtained by transition state theory using quantum chemistry calculations HF, MP2 (FULL) and B3LYP/6-311++G** level of theory. The details of intrinsic reaction coordinate calculation and potential energy surface calculations have also been described. These experimental and theoretical results suggest that the rate of HCl elimination is faster than that of H2O and HOCl elimination reaction.
In chapter 4, I have reported
thermal decomposition results obtained for 2-bromoethanol. The kinetic data have been obtained in the temperature range of 910-1102 K behind the reflected shock wave in a shock tube. Analyses of pre and post shock mixture using FT-IR and gas chromatographic techniques are discussed. Chemical kinetic simulation performed to simulate the product distribution is presented. The details of the β-substitution effect are explained. Both experimental and theoretical kinetic parameters of the unimolecular elimination of HBr and H2O have been presented. Theoretical results were obtained by transition state theory using quantum chemistry calculations at the HF, MP2 (FULL) and B3LYP/6-311++G** level of theory. The intrinsic…
Advisors/Committee Members: Arunan, E (advisor).
Subjects/Keywords: Haloethanol; Bromoethanol; Chloroethanol; Jet Propellant - Thermal Decomposition; Thermal Dissociation; Haloethanols - Thermal Decomposition; Jet Propellant - Ignition; 2-Chloroethanol; 2-Bromoethanol; JP-10; Thermodynamics
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APA (6th Edition):
Chakravarty, H. K. (2013). Thermal Decomposition Of Haloethanols And Ignition Of JP-10. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2109
Chicago Manual of Style (16th Edition):
Chakravarty, Harish Kumar. “Thermal Decomposition Of Haloethanols And Ignition Of JP-10.” 2013. Doctoral Dissertation, Indian Institute of Science. Accessed January 17, 2021.
http://etd.iisc.ac.in/handle/2005/2109.
MLA Handbook (7th Edition):
Chakravarty, Harish Kumar. “Thermal Decomposition Of Haloethanols And Ignition Of JP-10.” 2013. Web. 17 Jan 2021.
Vancouver:
Chakravarty HK. Thermal Decomposition Of Haloethanols And Ignition Of JP-10. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2013. [cited 2021 Jan 17].
Available from: http://etd.iisc.ac.in/handle/2005/2109.
Council of Science Editors:
Chakravarty HK. Thermal Decomposition Of Haloethanols And Ignition Of JP-10. [Doctoral Dissertation]. Indian Institute of Science; 2013. Available from: http://etd.iisc.ac.in/handle/2005/2109
28.
Garnero, Valentin.
(Méta)-noyaux constructifs et linéaires dans les graphes peu denses : Constructive and Linear (Meta)-Kernelisations on Sparse Graphs.
Degree: Docteur es, Informatique, 2016, Montpellier
URL: http://www.theses.fr/2016MONTT328
► En algorithmique et en complexité, la plus grande part de la recherche se base sur l’hypothèse que P ≠ NP (Polynomial time et Non deterministic…
(more)
▼ En algorithmique et en complexité, la plus grande part de la recherche se base sur l’hypothèse que P ≠ NP (Polynomial time et Non deterministic Polynomial time), c'est-à-dire qu'il existe des problèmes dont la solution peut être vérifiée mais non construite en temps polynomial. Si cette hypothèse est admise, de nombreux problèmes naturels ne sont pas dans P (c'est-à-dire, n'admettent pas d'algorithme efficace), ce qui a conduit au développement de nombreuses branches de l'algorithmique. L'une d'elles est la complexité paramétrée. Elle propose des algorithmes exacts, dont l'analyse est faite en fonction de la taille de l'instance et d'un paramètre. Ce paramètre permet une granularité plus fine dans l'analyse de la complexité.Un algorithme sera alors considéré comme efficace s'il est à paramètre fixé, c'est-à-dire, lorsque sa complexité est exponentielle en fonction du paramètre et polynomiale en fonction de la taille de l'instance. Ces algorithmes résolvent les problèmes de la classe FPT (Fixed Parameter Tractable).L'extraction de noyaux est une technique qui permet, entre autre, d’élaborer des algorithmes à paramètre fixé. Elle peut être vue comme un pré-calcul de l'instance, avec une garantie sur la compression des données. Plus formellement, une extraction de noyau est une réduction polynomiale depuis un problème vers lui même, avec la contrainte supplémentaire que la taille du noyau (l'instance réduite) est bornée en fonction du paramètre. Pour obtenir l’algorithme à paramètre fixé, il suffit de résoudre le problème dans le noyau, par exemple par une recherche exhaustive (de complexité exponentielle, en fonction du paramètre). L’existence d'un noyau implique donc l'existence d'un algorithme à paramètre fixé, la réciproque est également vraie. Cependant, l’existence d'un algorithme à paramètre fixé efficace ne garantit pas un petit noyau, c'est a dire un noyau dont la taille est linéaire ou polynomiale. Sous certaines hypothèses, il existe des problèmes n’admettant pas de noyau (c'est-à-dire hors de FPT) et il existe des problèmes de FPT n’admettant pas de noyaux polynomiaux.Un résultat majeur dans le domaine des noyaux est la construction d'un noyau linéaire pour le problème Domination dans les graphes planaires, par Alber, Fellows et Niedermeier.Tout d'abord, la méthode de décomposition en régions proposée par Alber, Fellows et Niedermeier, a permis de construire de nombreux noyaux pour des variantes de Domination dans les graphes planaires. Cependant cette méthode comportait un certain nombre d’imprécisions, ce qui rendait les preuves invalides. Dans la première partie de notre thèse, nous présentons cette méthode sous une forme plus rigoureuse et nous l’illustrons par deux problèmes : Domination Rouge Bleue et Domination Totale.Ensuite, la méthode a été généralisée, d'une part, sur des classes de graphes plus larges (de genre borné, sans-mineur, sans-mineur-topologique), d'autre part, pour une plus grande variété de problèmes. Ces méta-résultats prouvent l’existence de noyaux linéaires ou polynomiaux pour tout…
Advisors/Committee Members: Paul, Christophe (thesis director).
Subjects/Keywords: Complexité paramétrée; Extraction de noyaux; Décomposition en régions; Décomposition en protrusions; Parameterised complexity; Kernelisation; Region decomposition; Protrusion decomposition
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APA ·
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APA (6th Edition):
Garnero, V. (2016). (Méta)-noyaux constructifs et linéaires dans les graphes peu denses : Constructive and Linear (Meta)-Kernelisations on Sparse Graphs. (Doctoral Dissertation). Montpellier. Retrieved from http://www.theses.fr/2016MONTT328
Chicago Manual of Style (16th Edition):
Garnero, Valentin. “(Méta)-noyaux constructifs et linéaires dans les graphes peu denses : Constructive and Linear (Meta)-Kernelisations on Sparse Graphs.” 2016. Doctoral Dissertation, Montpellier. Accessed January 17, 2021.
http://www.theses.fr/2016MONTT328.
MLA Handbook (7th Edition):
Garnero, Valentin. “(Méta)-noyaux constructifs et linéaires dans les graphes peu denses : Constructive and Linear (Meta)-Kernelisations on Sparse Graphs.” 2016. Web. 17 Jan 2021.
Vancouver:
Garnero V. (Méta)-noyaux constructifs et linéaires dans les graphes peu denses : Constructive and Linear (Meta)-Kernelisations on Sparse Graphs. [Internet] [Doctoral dissertation]. Montpellier; 2016. [cited 2021 Jan 17].
Available from: http://www.theses.fr/2016MONTT328.
Council of Science Editors:
Garnero V. (Méta)-noyaux constructifs et linéaires dans les graphes peu denses : Constructive and Linear (Meta)-Kernelisations on Sparse Graphs. [Doctoral Dissertation]. Montpellier; 2016. Available from: http://www.theses.fr/2016MONTT328
Pontifical Catholic University of Rio de Janeiro
29.
FLÁVIA GALVÃO WANDEKOKEN.
[pt] DESENVOLVIMENTO DE MÉTODO PARA DETERMINAÇÃO DE AS, SB E
SE EM BIODIESEL E PETRÓLEO POR ICP OES COM INTRODUÇÃO DE AMOSTRA
POR GERAÇÃO DE HIDRETOS.
Degree: 2011, Pontifical Catholic University of Rio de Janeiro
URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18416
► [pt] Com o aumento da população mundial e o consequente aumento das atividades industriais e consumo de combustíveis, a poluição química vem sendo um grande…
(more)
▼ [pt] Com o aumento da população mundial e o
consequente aumento das atividades industriais e consumo de
combustíveis, a poluição química vem sendo um grande problema do
século XXI. Alternativas que possam minimizar tal problemática são
alvos de pesquisas, como o uso de biodiesel, um combustível
renovável e menos poluente. Elementos normalmente encontrados em
baixas concentrações, como As, Sb e Se, tornam-se tóxicos à saúde
humana quando em concentrações acima de certos limites e, por isso,
devem ser monitorados em diversas amostras, como combustíveis. Para
o Sb, a dose diária aceitável (DDA) é de 6 ug dia(-1) para cada kg
de peso corporal e para o Se, valores de concentração acima de
50(-200) ug por dia já são considerados tóxicos. O limite aceitável
de As em água potável é de 0,01 mg L(-1) e valores acima de 7,5 x
10-3 ug m(-3) são associados a risco de câncer de pulmão. Esses
elementos podem ser constituintes originais do petróleo e seus
derivados ou ser adicionados como contaminantes em alguma etapa do
refino. No caso do biodiesel, podem estar presentes, decorrente do
uso de fertilizantes e pesticidas nas lavouras das plantas que
deram origem ao óleo usado na produção desse combustível. Estes
elementos podem, durante o processo de combustão dos combustíveis
nos motores, ser liberados para a atmosfera. As baixas
concentrações em que esses elementos se encontram, normalmente,
estão abaixo do limite de detecção de algumas técnicas, como ICP
OES com introdução de amostra por nebulização pneumática
convencional. Nesse caso, uma alternativa viável é a introdução da
amostra por geração de vapor, que proporciona uma melhora
significativa na sensibilidade das técnicas analíticas. Este
trabalho teve como objetivo determinar simultaneamente As, Sb e Se
em amostras de óleo cru e biodiesel, utilizando HG-ICP OES. Para
tanto, as amostras tiveram que ser submetidas à decomposição ácida
em bloco digestor. Foram estudadas diferentes condições de
pré-redução (HCl, tiouréia e ácido ascórbico com KI), avaliadas
suas concentrações e tempo de aquecimento. As condições empregando
HCl e tiouréia foram as que apresentaram melhores resultados e
tiveram seus parâmetros otimizados multivariadamente, assim como os
parâmetros da geração de vapor: vazão de amostra, vazão de NaBH4
borohidreto de sódio e vazão do gás de arraste. Estabelecidas as
melhores condições para análise e respeitando-se as limitações da
técnica, o método foi avaliado através da análise de material
certificado de óleo combustível residual (NIST 1634c), biodiesel de
óleo de soja (NIST 2772) e biodiesel de gordura animal (NIST 2773),
empregando-se as duas condições de pré-redução citadas. Nesse caso,
o uso de HCl como pré-redutor foi mais eficiente, com recuperações
entre 90% e 99% para os 3 analitos. Já a pré-redução com tiouréia
foi eficiente só para Sb, com recuperação em torno de 104%,
enquanto as recuperações para As e Se foram entre 57% e 29%. Sendo
assim, para o método proposto empregou-se HCl como pré-redutor. As
condições otimizadas para a geração e empregadas para…
Advisors/Committee Members: TATIANA DILLENBURG SAINT PIERRE.
Subjects/Keywords: [pt] CALIBRACAO; [en] CALIBRATION; [pt] PETROLEO; [en] PETROLEUM; [pt] DECOMPOSICAO; [en] DECOMPOSITION; [pt] BIODIESEL; [en] BIODIESEL
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
WANDEKOKEN, F. G. (2011). [pt] DESENVOLVIMENTO DE MÉTODO PARA DETERMINAÇÃO DE AS, SB E
SE EM BIODIESEL E PETRÓLEO POR ICP OES COM INTRODUÇÃO DE AMOSTRA
POR GERAÇÃO DE HIDRETOS. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18416
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
WANDEKOKEN, FLÁVIA GALVÃO. “[pt] DESENVOLVIMENTO DE MÉTODO PARA DETERMINAÇÃO DE AS, SB E
SE EM BIODIESEL E PETRÓLEO POR ICP OES COM INTRODUÇÃO DE AMOSTRA
POR GERAÇÃO DE HIDRETOS.” 2011. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 17, 2021.
http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18416.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
WANDEKOKEN, FLÁVIA GALVÃO. “[pt] DESENVOLVIMENTO DE MÉTODO PARA DETERMINAÇÃO DE AS, SB E
SE EM BIODIESEL E PETRÓLEO POR ICP OES COM INTRODUÇÃO DE AMOSTRA
POR GERAÇÃO DE HIDRETOS.” 2011. Web. 17 Jan 2021.
Vancouver:
WANDEKOKEN FG. [pt] DESENVOLVIMENTO DE MÉTODO PARA DETERMINAÇÃO DE AS, SB E
SE EM BIODIESEL E PETRÓLEO POR ICP OES COM INTRODUÇÃO DE AMOSTRA
POR GERAÇÃO DE HIDRETOS. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2011. [cited 2021 Jan 17].
Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18416.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
WANDEKOKEN FG. [pt] DESENVOLVIMENTO DE MÉTODO PARA DETERMINAÇÃO DE AS, SB E
SE EM BIODIESEL E PETRÓLEO POR ICP OES COM INTRODUÇÃO DE AMOSTRA
POR GERAÇÃO DE HIDRETOS. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2011. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18416
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
30.
Carpier, Yann.
Contribution à l’analyse multi-échelles et multi-physiques du comportement mécanique de matériaux composites à matrice thermoplastique sous températures critiques : Contribution to the multi-scale and multi-physical analysis of the mechanical behaviour of thermoplastic matrix composite materials under critical temperatures.
Degree: Docteur es, Mécanique, 2018, Normandie
URL: http://www.theses.fr/2018NORMIR28
► L’utilisation croissante des matériaux composites à matrice thermoplastique dans l’industrie aéronautique passe par une meilleure compréhension de leur comportement mécanique lors d’une exposition à un…
(more)
▼ L’utilisation croissante des matériaux composites à matrice thermoplastique dans l’industrie aéronautique passe par une meilleure compréhension de leur comportement mécanique lors d’une exposition à un flux rayonnant (conséquence d’un incendie). Cette étude, portant sur le comportement thermo-mécanique de stratifiés tissés quasi-isotropes composés d’une matrice PPS renforcée par des fibres de carbone, se divise en 3 parties. Tout d’abord, la décomposition thermique du matériau et l’évolution de ses propriétés mécaniques avec la température sont étudiées. Ces données permettent ensuite d’appréhender le comportement de ces matériaux soumis à des chargements combinés (flux rayonnant et chargement mécanique en traction ou en compression, de type monotone à rupture et en fluage). La dernière partie vise à identifier les paramètres matériau nécessaires pour la simulation thermo-mécanique aux échelles macroscopique et mésoscopique.
The increasing use of thermoplastic-based composite materials in the aeronautical industry requires a better understanding of their mechanical behavior when exposed to radiant heat flux (consequence of a fire exposure). This study, which examines the thermo-mechanical behavior of quasi-isotropic woven laminates composed of PPS reinforced with carbon fibers, is divided into 3 parts. First, the thermal decomposition of the material and the evolution of its mechanical properties with temperature is studied. These data help to understand the behavior of these materials subjected to combined loads (radiant heat flux and tensile or compressive loadings). The last part aims to identify the material parameters necessary for thermo-mechanical simulation at macroscopic and mesoscopic scales.
Advisors/Committee Members: Vieille, Benoit (thesis director), Barbe, Fabrice (thesis director).
Subjects/Keywords: Chargements combinés; Simulation multi-échelles; Dégradation thermique; Décomposition thermique; Composite materials; Thermoplastic; Combined loadings; Multi-scale simulation; Thermal degradation; Thermal decomposition
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Carpier, Y. (2018). Contribution à l’analyse multi-échelles et multi-physiques du comportement mécanique de matériaux composites à matrice thermoplastique sous températures critiques : Contribution to the multi-scale and multi-physical analysis of the mechanical behaviour of thermoplastic matrix composite materials under critical temperatures. (Doctoral Dissertation). Normandie. Retrieved from http://www.theses.fr/2018NORMIR28
Chicago Manual of Style (16th Edition):
Carpier, Yann. “Contribution à l’analyse multi-échelles et multi-physiques du comportement mécanique de matériaux composites à matrice thermoplastique sous températures critiques : Contribution to the multi-scale and multi-physical analysis of the mechanical behaviour of thermoplastic matrix composite materials under critical temperatures.” 2018. Doctoral Dissertation, Normandie. Accessed January 17, 2021.
http://www.theses.fr/2018NORMIR28.
MLA Handbook (7th Edition):
Carpier, Yann. “Contribution à l’analyse multi-échelles et multi-physiques du comportement mécanique de matériaux composites à matrice thermoplastique sous températures critiques : Contribution to the multi-scale and multi-physical analysis of the mechanical behaviour of thermoplastic matrix composite materials under critical temperatures.” 2018. Web. 17 Jan 2021.
Vancouver:
Carpier Y. Contribution à l’analyse multi-échelles et multi-physiques du comportement mécanique de matériaux composites à matrice thermoplastique sous températures critiques : Contribution to the multi-scale and multi-physical analysis of the mechanical behaviour of thermoplastic matrix composite materials under critical temperatures. [Internet] [Doctoral dissertation]. Normandie; 2018. [cited 2021 Jan 17].
Available from: http://www.theses.fr/2018NORMIR28.
Council of Science Editors:
Carpier Y. Contribution à l’analyse multi-échelles et multi-physiques du comportement mécanique de matériaux composites à matrice thermoplastique sous températures critiques : Contribution to the multi-scale and multi-physical analysis of the mechanical behaviour of thermoplastic matrix composite materials under critical temperatures. [Doctoral Dissertation]. Normandie; 2018. Available from: http://www.theses.fr/2018NORMIR28
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Open Access Theses and Dissertations