subject:(deactivation)

Cornell University

1. Kelleher, Clarice. An Imaging Study Of The Photodissociation Of Ozone In The Huggins Band And O(1D) Reaction And Deactivation.

Degree: PhD, Chemistry and Chemical Biology, 2013, Cornell University

URL: http://hdl.handle.net/1813/33834

► Velocity mapped imaging (VMI) is used to study the photodissociation and reaction dynamics in both single and crossed molecular beams. In this dissertation the focus… (more)

Subjects/Keywords: Ozone Photodissocitation; O(1D) deactivation

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APA (6^th Edition):

Kelleher, C. (2013). An Imaging Study Of The Photodissociation Of Ozone In The Huggins Band And O(1D) Reaction And Deactivation. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/33834

Chicago Manual of Style (16^th Edition):

Kelleher, Clarice. “An Imaging Study Of The Photodissociation Of Ozone In The Huggins Band And O(1D) Reaction And Deactivation.” 2013. Doctoral Dissertation, Cornell University. Accessed March 08, 2021. http://hdl.handle.net/1813/33834.

MLA Handbook (7^th Edition):

Kelleher, Clarice. “An Imaging Study Of The Photodissociation Of Ozone In The Huggins Band And O(1D) Reaction And Deactivation.” 2013. Web. 08 Mar 2021.

Vancouver:

Kelleher C. An Imaging Study Of The Photodissociation Of Ozone In The Huggins Band And O(1D) Reaction And Deactivation. [Internet] [Doctoral dissertation]. Cornell University; 2013. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/1813/33834.

Council of Science Editors:

Kelleher C. An Imaging Study Of The Photodissociation Of Ozone In The Huggins Band And O(1D) Reaction And Deactivation. [Doctoral Dissertation]. Cornell University; 2013. Available from: http://hdl.handle.net/1813/33834

University of Illinois – Urbana-Champaign

2. Carbonaro, Sean. Continuous-flow photocatalytic treatment of pharmaceutical micropollutants: activity, inhibition, and deactivation of TiO2 photocatalysts in natural water matrices.

Degree: MS, 0231, 2012, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/34476

► Titanium dioxide (TiO2) photocatalysts have been shown to be effective at degrading a wide range of organic micropollutants under ideal laboratory solution conditions (e.g., deionized… (more)

▼ Titanium dioxide (TiO2) photocatalysts have been shown to be effective at degrading a wide range of organic micropollutants under ideal laboratory solution conditions (e.g., deionized water). However, little research has been performed regarding photocatalyst performance in more complex matrices representative of contaminated water sources (e.g., wastewater effluent, groundwater). Here, a benchtop continuous-flow reactor was developed for the purpose of studying the activity, inhibition, and deactivation of immobilized TiO2 photocatalysts during water treatment applications. As a demonstration, degradation of four model pharmaceutical micropollutants (iopromide, acetaminophen, sulfamethoxazole, and carbamazepine) was monitored in both deionized water (DI), biologically treated wastewater effluent (WWE), and groundwater (GW) to study the effects of non-target constituents present in the latter matrix. Reactor performance was shown to be sufficiently stable over 7 days when treating micropollutants in DI. When reactor influent was switched WWE, photocatalytic degradation of individual micropollutants was inhibited to varying degrees, ranging from 42 to 86%. However, most of the catalyst activity was recovered upon switching back to the DI matrix after 4 d, suggesting mostly competitive inhibition of the photocatalysts by WWE matrix components (e.g., effluent organic matter scavenging of OH) rather than irreversible catalyst deactivation. Experiments conducted using pretreated WWE and synthetic WWE mimic solutions indicated that both organic and inorganic constituents in WWE contributed to the observed catalyst inhibition. Analysis of immobilized TiO2 thin films after 4 d of continuous treatment of the WWE matrix indicated minor deterioration of the porous thin film. Photocatalytic degradation rates of micropollutants displayed different trends on a GW-exposed photocatalyst. Easily oxidizable compounds (acetaminophen and sulfamethoxazole) were little affected by catalyst exposure to GW, while more recalcitrant compounds (iopromide and carbamazepine) were significantly inhibited. Significant calcium precipitation was found on the catalyst using SEM-EDS. Oxalic acid was found to be an effective rinsing solution of the catalyst. It is suspected that calcium, manganese, and iron are the primary groundwater constituents responsible for catalyst deactivation, but further tests are needed to confirm. Results demonstrate the marked influence of non-target constituents present in complex matrices on long-term catalyst activity and highlight the need for increased study of this important issue to further the development of practical photocatalytic water treatment technologies. Advisors/Committee Members: Strathmann, Timothy J. (advisor).

Subjects/Keywords: photocatalyst; deactivation; inhibition; pharmaceuticals

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APA (6^th Edition):

Carbonaro, S. (2012). Continuous-flow photocatalytic treatment of pharmaceutical micropollutants: activity, inhibition, and deactivation of TiO2 photocatalysts in natural water matrices. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/34476

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Carbonaro, Sean. “Continuous-flow photocatalytic treatment of pharmaceutical micropollutants: activity, inhibition, and deactivation of TiO2 photocatalysts in natural water matrices.” 2012. Thesis, University of Illinois – Urbana-Champaign. Accessed March 08, 2021. http://hdl.handle.net/2142/34476.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Carbonaro, Sean. “Continuous-flow photocatalytic treatment of pharmaceutical micropollutants: activity, inhibition, and deactivation of TiO2 photocatalysts in natural water matrices.” 2012. Web. 08 Mar 2021.

Vancouver:

Carbonaro S. Continuous-flow photocatalytic treatment of pharmaceutical micropollutants: activity, inhibition, and deactivation of TiO2 photocatalysts in natural water matrices. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2012. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2142/34476.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Carbonaro S. Continuous-flow photocatalytic treatment of pharmaceutical micropollutants: activity, inhibition, and deactivation of TiO2 photocatalysts in natural water matrices. [Thesis]. University of Illinois – Urbana-Champaign; 2012. Available from: http://hdl.handle.net/2142/34476

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Saskatchewan

3. Si, Jordan. Investigating Efficiency of Engineered Water Nanostructures (EWNS) Generated via Electrospray Technique to Deactivate Surface Microbes in Livestock Barns.

Degree: 2018, University of Saskatchewan

URL: http://hdl.handle.net/10388/12995

► Electrospray has been studied for more than two centuries in applications such as drug delivery and air purification, and to study basic principles behind mass… (more)

▼ Electrospray has been studied for more than two centuries in applications such as drug delivery and air purification, and to study basic principles behind mass spectrometry electrohydrodynamic atomization. More recently, electrospray systems have been used to generate engineered water nanostructures (EWNS). EWNS are generated by concurrently electrospraying and ionizing water. During the production of EWNS, reactive oxygen species (ROS) are generated, these ROS have the ability to deactivate bacteria. As such, EWNS may be a promising chemical free surface decontamination method. The objective of the research work was to determine the optimal operating condition that produced the highest deactivation efficiency of prevalent bacteria in livestock barns. Pathogenic bacteria in livestock barns contribute to animal and human illness and disease, and a non-chemical decontaminating method, such as EWNS, would benefit the industry. To date there is no research investigating the optimal parameters for EWNS efficiency to deactivate bacteria. Parameters under study included the effect of pH, conductivity, distance between needle tip and counter electrode, water flow rate and voltage on the performance of EWNS. The research work was conducted in two phases. In phase I, a systematics study was undertaken to investigate the electrical current and electrosprayed area under a broad range of operating parameters including voltage level and polarity, pH, conductivity, needle tip to counter electrode distance and liquid flow rate. In phase II, the bacteria deactivation efficiency of EWNS for Escherichia.coli and poultry barn bacteria were investigated. The optimal EWNS operating condition that produced the highest deactivation efficiency (4 logs or 99.99%) for E.coli was -6.6 kV, 2 cm distance between needle tip and counter electrode, 2 µL/min, pH=7, K=0.20 mS/cm and 25 min of exposure time. Further, the results indicated that the nanospray technology is a potential chemical-free alternative to conventional methods (e.g., chlorine spraying) in decontaminating surfaces of livestock buildings. Scaling up the technology for larger scale applications and in-barn tests are required in future research. Advisors/Committee Members: Zhang, Lifeng, Kirychuk, Shelley, Niu, Catherine, Predicala, Bernardo, Chang, Wonjae.

Subjects/Keywords: Electrospray; bacteria deactivation efficiency

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APA (6^th Edition):

Si, J. (2018). Investigating Efficiency of Engineered Water Nanostructures (EWNS) Generated via Electrospray Technique to Deactivate Surface Microbes in Livestock Barns. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/12995

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Si, Jordan. “Investigating Efficiency of Engineered Water Nanostructures (EWNS) Generated via Electrospray Technique to Deactivate Surface Microbes in Livestock Barns.” 2018. Thesis, University of Saskatchewan. Accessed March 08, 2021. http://hdl.handle.net/10388/12995.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Si, Jordan. “Investigating Efficiency of Engineered Water Nanostructures (EWNS) Generated via Electrospray Technique to Deactivate Surface Microbes in Livestock Barns.” 2018. Web. 08 Mar 2021.

Vancouver:

Si J. Investigating Efficiency of Engineered Water Nanostructures (EWNS) Generated via Electrospray Technique to Deactivate Surface Microbes in Livestock Barns. [Internet] [Thesis]. University of Saskatchewan; 2018. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10388/12995.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Si J. Investigating Efficiency of Engineered Water Nanostructures (EWNS) Generated via Electrospray Technique to Deactivate Surface Microbes in Livestock Barns. [Thesis]. University of Saskatchewan; 2018. Available from: http://hdl.handle.net/10388/12995

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New South Wales

4. Althenayan, Faisal. Propane dry reforming over cerium promoted catalyst: enhancement of synthesis gas production under reduced carbon deposition.

Degree: Chemical Sciences & Engineering, 2011, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/51476 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10163/SOURCE02?view=true

► Among others, the light hydrocarbon (C1-C4 alkanes) dry reforming process has attracted considerable attention with increasing global oil price, for developing sustainable environmentally-compatible synthesis gas… (more)

▼ Among others, the light hydrocarbon (C1-C4 alkanes) dry reforming process has attracted considerable attention with increasing global oil price, for developing sustainable environmentally-compatible synthesis gas (H2/CO mixtures) production and utilisation technologies. However, the foremost advantage of immediate suitability for gas-to-liquids (GTL) fuels’ conversion has been prevented by severe carbon deposition, the main challenge that rapidly deactivates the catalyst and the attendant economic implications. As a result, the principal goal of this study was to improve the dry reforming process through two main strategies, namely: carbon-resilient catalyst design, and reactor operation. In particular, a bimetallic catalyst which is based on Ni, the key ingredient in industrial reforming catalysts, was promoted by cerium as a rare earth metal that is well known for its high capacity for oxygen storage as well as its flexibility in redox state.Catalysts were prepared by co-impregnation using cobalt, nickel and cerium nitrate on γ-alumina support. Bimetallic catalyst of 5wt%Co-10wt%Ni was promoted with 0-2.5wt% cerium in 0.5wt% increments. Catalyst physicochemical properties were measured via various techniques including N2-physisorption, H2-chemisorption, temperature programmed desorption of NH3, CO2, C3H8, CH4 and CO, UV–vis diffuse reflectance spectroscopy. Morphological examination such as XRD, TEM and SEM and thermogravimetric analysis for calcination, reduction and oxidation were also undertaken. CO2-TPD results demonstrated the basicity of the promoted catalyst was nearly doubled. XRD analysis confirmed the presence of CeO2 and TEM images verified the metal dispersion data obtained from H2-chemisorption.Catalyst evaluation, reaction kinetics studies and O2-co-feeding investigation were performed in a fixed-bed reactor of 15 mm ID at 798–923 K under atmospheric pressure. The increase in catalyst basicity was reflected in catalyst activity as syngas production was successfully increased with Ce content before attaining a plateau at 1.5wt% while total carbon in spent catalysts was reduced to almost zero beyond this critical Ce loading. Conversely, reforming kinetic and deactivation coefficients that estimated from transient data over longevity runs of 72 h, validated the improvement in the promoted catalyst. Nevertheless, reactor operational studies indicated the ability to enhance syngas production under O2-co-feeding and fluidisation approaches.

Subjects/Keywords: Deactivation; Dry Reforming; Cerium

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APA (6^th Edition):

Althenayan, F. (2011). Propane dry reforming over cerium promoted catalyst: enhancement of synthesis gas production under reduced carbon deposition. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/51476 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10163/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Althenayan, Faisal. “Propane dry reforming over cerium promoted catalyst: enhancement of synthesis gas production under reduced carbon deposition.” 2011. Doctoral Dissertation, University of New South Wales. Accessed March 08, 2021. http://handle.unsw.edu.au/1959.4/51476 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10163/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Althenayan, Faisal. “Propane dry reforming over cerium promoted catalyst: enhancement of synthesis gas production under reduced carbon deposition.” 2011. Web. 08 Mar 2021.

Vancouver:

Althenayan F. Propane dry reforming over cerium promoted catalyst: enhancement of synthesis gas production under reduced carbon deposition. [Internet] [Doctoral dissertation]. University of New South Wales; 2011. [cited 2021 Mar 08]. Available from: http://handle.unsw.edu.au/1959.4/51476 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10163/SOURCE02?view=true.

Council of Science Editors:

Althenayan F. Propane dry reforming over cerium promoted catalyst: enhancement of synthesis gas production under reduced carbon deposition. [Doctoral Dissertation]. University of New South Wales; 2011. Available from: http://handle.unsw.edu.au/1959.4/51476 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:10163/SOURCE02?view=true

Colorado School of Mines

5. Xu, Mengze. Syntheses and applications of meso-microporous zeolites in vapor phase upgrading of biomass.

Degree: PhD, Chemistry, 2017, Colorado School of Mines

URL: http://hdl.handle.net/11124/171831

► Despite the fact that zeolites have been applied to biomass upgrading for decades, there are still various obstacles that need to be overcome. In applications… (more)

▼ Despite the fact that zeolites have been applied to biomass upgrading for decades, there are still various obstacles that need to be overcome. In applications of using zeolites to catalyze biomass pyrolysis vapors, the yields of hydrocarbons are relatively low and catalysts frequently suffer from fast deactivation. Diffusion limitation is widely accepted to be the dominant reason for the two challenges above. Researchers have been intensively engaged in developing hierarchical zeolites which possess both introduced mesopores and original micropores to accelerate the diffusion of complex intermediates and products from biomass pyrolysis vapors. A number of hierarchical zeolites have been created in recent years. However, most of these novel structures are only involved in simplified model compounds to demonstrate potential in promising applications in real biomass. It has become increasingly important to investigate the catalytic activity of hierarchical zeolites in biomass, due to the raised economic and environmental requirements to commercialize biofuels upgraded from biomass. I synthesized a multilayered MFI nanosheet zeolite, a category of hierarchical zeolites which performed well in model reactions (methanol to gasoline). The nanosheet zeolite was thoroughly characterized. It possessed uniform mesopores on the external surface and micropores on the internal surface. The catalytic activity of MFI nanosheet was investigated via two complementary instruments, micropyrolyzer-GCMS and molecular beam mass spectrometer (MBMS). Hydrocarbon yields of biomass over the nanosheet were found to be competitive to the yields over conventional ZSM-5 catalyst which possessed similar acid sites but lacked hierarchical structure. The species of hydrocarbon products were the same over the two catalysts, implying that mesopores did not change the distribution of products. Meanwhile, the completed deactivation process of MFI nanosheet was studied. It was found that MFI nanosheet achieved a lifetime approximately three times of conventional ZSM-5. However, coke (carbonaceous by-products) contents on MFI nanosheet were higher than ZSM-5. Coked catalysts were collected at various biomass-to-catalyst ratios and characterized to track the change of pore volumes and active acid sites in the process of deactivation. Based on the results of catalytic activities and characterizations, it is suggested that mesoporous MFI nanosheet has much better accessibility to active acid sites, which enables the longer catalyst lifetime while resulting in more coke formation. Advisors/Committee Members: Richards, Ryan (advisor), Trewyn, Brian (advisor), Ciobanu, Cristian V. (committee member), Pylypenko, Svitlana (committee member), Yang, Yongan (committee member).

Subjects/Keywords: deactivation mechanism; mesoporous zeolites; fast deactivation; biomass upgrading

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APA (6^th Edition):

Xu, M. (2017). Syntheses and applications of meso-microporous zeolites in vapor phase upgrading of biomass. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/171831

Chicago Manual of Style (16^th Edition):

Xu, Mengze. “Syntheses and applications of meso-microporous zeolites in vapor phase upgrading of biomass.” 2017. Doctoral Dissertation, Colorado School of Mines. Accessed March 08, 2021. http://hdl.handle.net/11124/171831.

MLA Handbook (7^th Edition):

Xu, Mengze. “Syntheses and applications of meso-microporous zeolites in vapor phase upgrading of biomass.” 2017. Web. 08 Mar 2021.

Vancouver:

Xu M. Syntheses and applications of meso-microporous zeolites in vapor phase upgrading of biomass. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2017. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/11124/171831.

Council of Science Editors:

Xu M. Syntheses and applications of meso-microporous zeolites in vapor phase upgrading of biomass. [Doctoral Dissertation]. Colorado School of Mines; 2017. Available from: http://hdl.handle.net/11124/171831

Oregon State University

6. Lopez, David A. (David Anthony). Examination of Immobilized TiO₂ Nanoparticle Photocatalytic Treatment of Stormwater by LilyPads.

Degree: MS, Environmental Engineering, 2015, Oregon State University

URL: http://hdl.handle.net/1957/57498

► Stormwater runoff is a significant cause for impairment of many water bodies, a problem that will inevitably escalate due to increasing land-cover change associated with… (more)

▼ Stormwater runoff is a significant cause for impairment of many water bodies, a problem that will inevitably escalate due to increasing land-cover change associated with urbanization. The effect of stormwater runoff has spurred legislation and the subsequent development and adoption of Best Management Practices (BMPs) to treat stormwater. This work evaluates the immobilized TiO₂ nanoparticle photocatalytic treatment of stormwater by Puralytic's LilyPad technology, both in lab-scale batch test and field-scale deployment at the OSU-Benton County Green Stormwater Infrastructure Research (OGSIR) Facility. The performance during field-scale deployment is compared to performance data for other BMPs. There were several key findings during lab tests. First, during lab tests with synthetic stormwater (SSW) containing multiple metals (Cu(II), Zn(II), and Fe(II)), Fe(II) inhibited the removal rates of Cu(II) and Zn(II). Second, in SSW containing PO₄³⁻, the LilyPad was responsible for a 22% reduction in phosphate. Third, at chemical oxygen demand (COD) concentrations comparable to stormwater from the OGSIR (170 ppm COD), potassium acid phthalate (KHP), a model complex organic, inhibited PurBlue dye removal via competitive adsorption. Fourth, a LilyPad prototype, utilizing a polypropylene substrate for TiO₂ nanoparticle immobilization, self-catalyzed (the TiO₂ photocatalytic degradation of the LilyPad's polypropylene immobilization substrate) under UV lamps, raising dissolved organic content (DOC) by as much as 28 ppm C. The magnitude of self-catalyization was greatest at low DOC concentrations with the rate decreasing with increasing DOC concentrations. When DOC concentrations in stormwater were higher than 10 ppm C, the point at which self-catalyization potentially ceases, the LilyPad was able to remove DOC at 0.24 ppm C/hr from 22 ppm C to 11 ppm C and at 0.14 ppm C/hr from 14 ppm C to 8 ppm C. At the field-scale, the LilyPad/retention pond combination does well compared to other stormwater BMPs at removing heavy metals (Cu(II), Zn(II) and Fe(II)), nitrate and DOC from the stormwater at the OGSIR; however, the LilyPad's contribution to the removal is difficult to ascertained due to similar pollutant removal during periods when the LilyPad was present versus periods when the LilyPad was not present. Also, the LilyPad was shown to become 50% fouled after 122 hours in stormwater at the OGSIR with the percent fouled rising to 80% after 800 hours. Advisors/Committee Members: Radniecki, Tyler S. (advisor), Nason, Jeffrey (committee member).

Subjects/Keywords: deactivation; Runoff – Purification – Heavy metals removal

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APA (6^th Edition):

Lopez, D. A. (. A. (2015). Examination of Immobilized TiO₂ Nanoparticle Photocatalytic Treatment of Stormwater by LilyPads. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/57498

Chicago Manual of Style (16^th Edition):

Lopez, David A (David Anthony). “Examination of Immobilized TiO₂ Nanoparticle Photocatalytic Treatment of Stormwater by LilyPads.” 2015. Masters Thesis, Oregon State University. Accessed March 08, 2021. http://hdl.handle.net/1957/57498.

MLA Handbook (7^th Edition):

Lopez, David A (David Anthony). “Examination of Immobilized TiO₂ Nanoparticle Photocatalytic Treatment of Stormwater by LilyPads.” 2015. Web. 08 Mar 2021.

Vancouver:

Lopez DA(A. Examination of Immobilized TiO₂ Nanoparticle Photocatalytic Treatment of Stormwater by LilyPads. [Internet] [Masters thesis]. Oregon State University; 2015. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/1957/57498.

Council of Science Editors:

Lopez DA(A. Examination of Immobilized TiO₂ Nanoparticle Photocatalytic Treatment of Stormwater by LilyPads. [Masters Thesis]. Oregon State University; 2015. Available from: http://hdl.handle.net/1957/57498

Colorado State University

7. Harms, Jonathan E. Structure-function relationships underlying GluA2 mechanisms of deactivation, desensitization, and modulation.

Degree: PhD, Biomedical Sciences, 2013, Colorado State University

URL: http://hdl.handle.net/10217/78826

► Glutamate is the primary excitatory neurotransmitter in the central nervous system, where it is principally responsible for mediating excitatory neurotransmission. Ligand-gated receptors to glutamate, such… (more)

▼ Glutamate is the primary excitatory neurotransmitter in the central nervous system, where it is principally responsible for mediating excitatory neurotransmission. Ligand-gated receptors to glutamate, such as the a-amino-3-hydroxy-5-methyl-isoxazole-propionic acid (AMPA) receptor, are responsible for many cognitive processes; with the AMPA receptor showing an essential role in learning, memory, and synaptic plasticity. As many mental illnesses and diseases show underlying cognitive complications, therapeutic drugs that can alleviate these cognitive deficits show tremendous potential benefit. However, despite great interest and continued advancement, progress of drugs through clinical trials into available treatments has been slow and problematic. One potential reason for the slow progress of drug development is a lack of basic understanding for how compounds bind to AMPA receptors and upregulate their function. Presented here are several studies aimed to better understand how structural interactions regulate AMPA receptor mechanisms of gating and modulation. These studies combine fast-perfusion electrophysiology capable of simulating synaptic events with structural information obtained from x-ray crystallography studies to analyze potential mechanisms of allosteric modulation. Promisingly, we have identified potential patterns relating modulator properties such as size and rigidity with their observed physiological effects. Such patterns suggest that information from these studies can facilitate design of more targeted and efficacious cognition enhancing drugs. In addition to this drug analysis, we identify a new potential drug target site: the AMPA receptor outer vestibule near the ion-conducting pore. We further characterize that alteration to this site acts independently of other modulators, providing a site for modulators that may accompany current pharmacological therapies. Together, these studies demonstrate that structural information can be successfully applied to the process of drug design, with the added benefit of enhancing our understanding for molecular mechanisms of AMPA receptor function. Advisors/Committee Members: Partin, Kathryn M. (advisor), Amberg, Gregory C. (committee member), Prasad, Ashok (committee member), Tamkun, Michael M. (committee member).

Subjects/Keywords: AMPA receptor; kinetic model; glutamate; deactivation

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APA (6^th Edition):

Harms, J. E. (2013). Structure-function relationships underlying GluA2 mechanisms of deactivation, desensitization, and modulation. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/78826

Chicago Manual of Style (16^th Edition):

Harms, Jonathan E. “Structure-function relationships underlying GluA2 mechanisms of deactivation, desensitization, and modulation.” 2013. Doctoral Dissertation, Colorado State University. Accessed March 08, 2021. http://hdl.handle.net/10217/78826.

MLA Handbook (7^th Edition):

Harms, Jonathan E. “Structure-function relationships underlying GluA2 mechanisms of deactivation, desensitization, and modulation.” 2013. Web. 08 Mar 2021.

Vancouver:

Harms JE. Structure-function relationships underlying GluA2 mechanisms of deactivation, desensitization, and modulation. [Internet] [Doctoral dissertation]. Colorado State University; 2013. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10217/78826.

Council of Science Editors:

Harms JE. Structure-function relationships underlying GluA2 mechanisms of deactivation, desensitization, and modulation. [Doctoral Dissertation]. Colorado State University; 2013. Available from: http://hdl.handle.net/10217/78826

University of Newcastle

8. Hosseiniamoli, Hadi. Catalytic combustion of ventilation air methane - an in depth study of catalyst deactivation.

Degree: PhD, 2018, University of Newcastle

URL: http://hdl.handle.net/1959.13/1385415

►

Research Doctorate - Doctor of Philosophy (PhD)

In this thesis, a systematic approach to the development of catalysts was undertaken for use in the combustion… (more)

Subjects/Keywords: catalyst; deactivation; oxidation; ventilation air methane

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APA (6^th Edition):

Hosseiniamoli, H. (2018). Catalytic combustion of ventilation air methane - an in depth study of catalyst deactivation. (Doctoral Dissertation). University of Newcastle. Retrieved from http://hdl.handle.net/1959.13/1385415

Chicago Manual of Style (16^th Edition):

Hosseiniamoli, Hadi. “Catalytic combustion of ventilation air methane - an in depth study of catalyst deactivation.” 2018. Doctoral Dissertation, University of Newcastle. Accessed March 08, 2021. http://hdl.handle.net/1959.13/1385415.

MLA Handbook (7^th Edition):

Hosseiniamoli, Hadi. “Catalytic combustion of ventilation air methane - an in depth study of catalyst deactivation.” 2018. Web. 08 Mar 2021.

Vancouver:

Hosseiniamoli H. Catalytic combustion of ventilation air methane - an in depth study of catalyst deactivation. [Internet] [Doctoral dissertation]. University of Newcastle; 2018. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/1959.13/1385415.

Council of Science Editors:

Hosseiniamoli H. Catalytic combustion of ventilation air methane - an in depth study of catalyst deactivation. [Doctoral Dissertation]. University of Newcastle; 2018. Available from: http://hdl.handle.net/1959.13/1385415

KTH

9. Barrientos, Javier. Deaktivering av metanisering katalysatorer.

Degree: Chemical Science and Engineering (CHE), 2012, KTH

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156183

►

A titania-supported nickel catalyst was prepared and tested in methanation in order to evaluate its catalytic properties (activity, selectivity and specially, activity loss), and… (more)

Subjects/Keywords: methanation; carbon formation; deactivation; titania; nickel

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APA (6^th Edition):

Barrientos, J. (2012). Deaktivering av metanisering katalysatorer. (Thesis). KTH. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156183

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Barrientos, Javier. “Deaktivering av metanisering katalysatorer.” 2012. Thesis, KTH. Accessed March 08, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156183.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Barrientos, Javier. “Deaktivering av metanisering katalysatorer.” 2012. Web. 08 Mar 2021.

Vancouver:

Barrientos J. Deaktivering av metanisering katalysatorer. [Internet] [Thesis]. KTH; 2012. [cited 2021 Mar 08]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156183.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Barrientos J. Deaktivering av metanisering katalysatorer. [Thesis]. KTH; 2012. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156183

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech

10. Burch, Coleman Patrick. Adhesion Fundamentals in Spotted Gum (Corymbia citriodora).

Degree: MS, Forest Products, 2015, Virginia Tech

URL: http://hdl.handle.net/10919/78206

► The goal of this project was to advance adhesion science and technology related to the Australian hardwood spotted gum (Corymbia citriodora). Plantation-grown spotted gum exhibits… (more)

▼ The goal of this project was to advance adhesion science and technology related to the Australian hardwood spotted gum (Corymbia citriodora). Plantation-grown spotted gum exhibits poor adhesion properties in comparison with similar woods, such as Gympie messmate (Eucalyptus cloeziana). To better understand adhesion differences between these two woods, this research compared and contrasted the surface chemistries of plantation-grown spotted gum and Gympie messmate with a particular focus on sensitivity to thermal deactivation. Wetting measurements were performed using the sessile drop method. Initial and equilibrium contact angles, time-dependent wetting, and surface energy were determined. Time-dependent wetting and equilibrium contact angles were most informative. Initial contact angles and surface energy calculated with them were misleading and often generated anomalous results. Heating water-saturated wood to mild surface temperatures (105 deg C, directly after evaporative cooling) severely deactivated spotted gum but not Gympie messmate. This suggests conventional kiln drying appears unsuitable for spotted gum while amenable for Gympie messmate. Spotted gum likely requires non-aqueous, low surface tension adhesives or aqueous adhesives formulated with surface active wetting agents. Water-saturation (followed by room-temperature vacuum drying) substantially altered the surface chemistries of both woods, making them more hydrophilic. Consequently, the question was raised of whether a water-spray onto the wood surface prior to adhesive application could improve bonding. If so, this simple, industrially-feasible treatment could prove very beneficial to the wood composites industry. Water-saturation also revealed differences in the two wood's water permeability, which has implications for adhesive penetration and wood drying and may additionally help explain adhesion differences. Analysis of the plantation-grown heartwood (inner, middle, and outer heartwood regions) revealed significant wetting differences on spotted gum with only minor differences on Gympie messmate. The Australian woods were compared to two North American woods-loblolly pine (Pinus taeda) and Douglas-fir (Pseudotsuga menziesii). Examining water wetting measurements, the Australian and North American woods exhibited some interesting similarities. However, methylene iodide wetting measurements revealed that the Australian woods were quite different from the North American samples studied here. Advisors/Committee Members: Frazier, Charles E. (committeechair), Zink-Sharp, Audrey G. (committee member), Roman, Maren (committee member).

Subjects/Keywords: Surface energy; thermal deactivation; wetting; wood

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APA (6^th Edition):

Burch, C. P. (2015). Adhesion Fundamentals in Spotted Gum (Corymbia citriodora). (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/78206

Chicago Manual of Style (16^th Edition):

Burch, Coleman Patrick. “Adhesion Fundamentals in Spotted Gum (Corymbia citriodora).” 2015. Masters Thesis, Virginia Tech. Accessed March 08, 2021. http://hdl.handle.net/10919/78206.

MLA Handbook (7^th Edition):

Burch, Coleman Patrick. “Adhesion Fundamentals in Spotted Gum (Corymbia citriodora).” 2015. Web. 08 Mar 2021.

Vancouver:

Burch CP. Adhesion Fundamentals in Spotted Gum (Corymbia citriodora). [Internet] [Masters thesis]. Virginia Tech; 2015. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10919/78206.

Council of Science Editors:

Burch CP. Adhesion Fundamentals in Spotted Gum (Corymbia citriodora). [Masters Thesis]. Virginia Tech; 2015. Available from: http://hdl.handle.net/10919/78206

Colorado State University

11. Page, Christopher Barry. Simulation and analysis of an 18L natural-gas engine with a focus on cylinder deactivation and exhaust pressure dynamics.

Degree: MS(M.S.), Mechanical Engineering, 2016, Colorado State University

URL: http://hdl.handle.net/10217/176640

► A GT-Power model of a Waukesha VGF-18 engine was created to investigate engine performance and pressure wave dynamics in the exhaust system of an 18L… (more)

▼ A GT-Power model of a Waukesha VGF-18 engine was created to investigate engine performance and pressure wave dynamics in the exhaust system of an 18L natural-gas engine. Exhaust pressure plays a large role in engine dynamics as it affects in-cylinder temperature, pressure, power output, emissions, air exchange and exhaust gas recirculation. The model was also evaluated to predict performance differences between cylinder deactivation and nominal six-cylinder operation. Cylinder deactivation allows for experimental modifications to be made on a small number of cylinders while still being able to extrapolate the data to fit the fully operational engine. Experimental cylinder deactivation results in a decrease in cost, time spent on labor, and propagation of uncertainty during experimental modification. An analysis was made on the effects of cylinder deactivation on engine operation and exhaust pressure dynamics. The flow solver was verified analytically and the combustion solver was verified with Chemkin. The results were validated with experimental data and the general engine parameters and fuel flow were found to have a predictive confidence level over 95%, the combustion, temperatures, and manifold pressures calculated by the model were found to have a predictive confidence level just above 90%. Following validation there were several geometric modifications done to the exhaust manifold and exhaust runners of the model to determine the pressure wave dynamics at the exhaust port of cylinder 1 as well as the engine performance. The tests found that modifying the exhaust runner length parameter had the greatest effect on engine performance and that modifying the exhaust manifold aspect ratio (cross-sectional area over length) had the greatest effect on average exhaust pressure. Five of the six cylinders were deactivated in the model by replacing the combustion chambers with purely mechanical piston-cylinders full of non-combustible air. It was found that cylinder deactivation resulted in a increase in the frictional affects as a percentage of brake power, but the difference was significantly less for the cylinder deactivation method where the pistons are removed from the inactive cylinders. Advisors/Committee Members: Olsen, Daniel (advisor), Marchese, Anthony (committee member), De Miranda, Michael (committee member).

Subjects/Keywords: decomissioning; natural-gas; simulation; exhaust; deactivation; pressure

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APA (6^th Edition):

Page, C. B. (2016). Simulation and analysis of an 18L natural-gas engine with a focus on cylinder deactivation and exhaust pressure dynamics. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/176640

Chicago Manual of Style (16^th Edition):

Page, Christopher Barry. “Simulation and analysis of an 18L natural-gas engine with a focus on cylinder deactivation and exhaust pressure dynamics.” 2016. Masters Thesis, Colorado State University. Accessed March 08, 2021. http://hdl.handle.net/10217/176640.

MLA Handbook (7^th Edition):

Page, Christopher Barry. “Simulation and analysis of an 18L natural-gas engine with a focus on cylinder deactivation and exhaust pressure dynamics.” 2016. Web. 08 Mar 2021.

Vancouver:

Page CB. Simulation and analysis of an 18L natural-gas engine with a focus on cylinder deactivation and exhaust pressure dynamics. [Internet] [Masters thesis]. Colorado State University; 2016. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10217/176640.

Council of Science Editors:

Page CB. Simulation and analysis of an 18L natural-gas engine with a focus on cylinder deactivation and exhaust pressure dynamics. [Masters Thesis]. Colorado State University; 2016. Available from: http://hdl.handle.net/10217/176640

Colorado State University

12. Ladd, John. Conversion of low BMEP 4-cylinder to high BMEP 2-cylinder large bore natural gas engine.

Degree: MS(M.S.), Mechanical Engineering, 2016, Colorado State University

URL: http://hdl.handle.net/10217/176615

► There are more than 6,000 integral compressor engines in use on US natural gas pipelines, operating 24 hours a day, 365 days a year. Many… (more)

▼ There are more than 6,000 integral compressor engines in use on US natural gas pipelines, operating 24 hours a day, 365 days a year. Many of these engines have operated continuously for more than 50 years, with little to no modifications. Due to recent emission regulations at the local, state and federal levels much of the aging infrastructure requires retrofit technology to remain within compliance. The Engines and Energy Conversion Laboratory was founded to test these retrofit technologies on its large bore engine testbed (LBET). The LBET is a low brake mean effective pressure (BMEP) Cooper Bessemer GMVTF-4. Newer GMV models, constructed in 1980’s, utilize turbocharging to increase the output power, achieving BMEP’s nearly double that of the LBET. To expand the lab’s testing capability and to reduce the LBET’s running cost: material testing, in-depth modeling, and on engine testing was completed to evaluate the feasibility of uprating the LBET to a high BMEP two cylinder engine. Due to the LBET’s age, the crankcase material properties were not known. Material samples were removed from engine to conduct an in-depth material analysis. It was found that the crankcase was cast out of a specific grade of gray iron, class 25 meehanite. A complete three dimensional model of the LBET’s crankcase and power cylinders was created. Using historical engine data, the force inputs were created for a finite element analysis model of the LBET, to determine the regions of high stress. The areas of high stress were instrumented with strain gauges to iterate and validate the model’s findings. Several test cases were run at the high and intermediate BMEP engine conditions. The model found, at high BMEP conditions the LBET would operate at the fatigue limit of the class 25 meehanite, operating with no factor of safety but the intermediate case were deemed acceptable. Advisors/Committee Members: Olsen, Daniel B. (advisor), Petro, John (committee member), Bienkiewicz, Bogusz (committee member).

Subjects/Keywords: cylinder deactivation; uprate; GMV; Cooper Bessemer

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APA (6^th Edition):

Ladd, J. (2016). Conversion of low BMEP 4-cylinder to high BMEP 2-cylinder large bore natural gas engine. (Masters Thesis). Colorado State University. Retrieved from http://hdl.handle.net/10217/176615

Chicago Manual of Style (16^th Edition):

Ladd, John. “Conversion of low BMEP 4-cylinder to high BMEP 2-cylinder large bore natural gas engine.” 2016. Masters Thesis, Colorado State University. Accessed March 08, 2021. http://hdl.handle.net/10217/176615.

MLA Handbook (7^th Edition):

Ladd, John. “Conversion of low BMEP 4-cylinder to high BMEP 2-cylinder large bore natural gas engine.” 2016. Web. 08 Mar 2021.

Vancouver:

Ladd J. Conversion of low BMEP 4-cylinder to high BMEP 2-cylinder large bore natural gas engine. [Internet] [Masters thesis]. Colorado State University; 2016. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10217/176615.

Council of Science Editors:

Ladd J. Conversion of low BMEP 4-cylinder to high BMEP 2-cylinder large bore natural gas engine. [Masters Thesis]. Colorado State University; 2016. Available from: http://hdl.handle.net/10217/176615

KTH

13. HANNAN, KHALID BIN. Organiska kväveföreningars påverkan på vätebehandlingsanläggningens prestanda.

Degree: Chemical Science and Engineering (CHE), 2014, KTH

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-172334

► Various distillates are treated with hydrogen gas during hydrotreatment in the presence of catalyst in order to reduce the sulfur and aromatic content of… (more)

▼ Various distillates are treated with hydrogen gas during hydrotreatment in the presence of catalyst in order to reduce the sulfur and aromatic content of the product. Optimal hydrotreater performance is essential for producing Nynas specialty oils, in order to fulfill the planned production volume and to meet the product specification. Loss of catalyst activity is inevitable during the production. To adjust for the impact of catalyst deactivation, different process variables are manipulated. Different distillates affect the catalyst in different ways due to the variation in distillate composition. Distillates with higher organic nitrogen content and running at a lower temperature tend to deactivate the catalyst more due to the adsorption of nitrogen compounds on the active sites of the catalyst and their slow nature of desorption. In this master thesis, different catalyst deactivation mechanisms with a focus on nitrogen deactivation have been studied. Since nitrogen is not normally measured at Nynas, nitrogen content of different distillates and products and how these values change during operation was not known. Different distillates, blend of distillates and different products were measured to estimate roughly the typical nitrogen value of the distillates and products. The temperature data inside the reactors were analyzed to calculate and plot WABT (weighted average bed temperature) during different product runs and to see whether there is a correlation between the nitrogen content of the feed and operation severity (increase in WABT). Historical process data from hydrotreater unit 2 (mostly from 2013-2014) were analyzed with a view to finding out signs of catalyst deactivation. Similar product runs were also analyzed and compared to see how the catalysts performed at different periods of time. A kinetic model, based on HDS kinetics, has been used for following up two product runs. To do so, sulfur content of the feed and product were measured. Aromatic content of the product was also measured to see whether the product was on specification. .From the calculation and plotting of WABTs, it could be seen that there is an increase in WABT during the product runs operating at lower temperatures and with higher nitrogen content. From the comparison of two P3 product runs at two different time periods, it could be seen that ∆T development over one bed (amount of reaction over the bed) was much lower at one time. This can possibly be a sign of catalyst deactivation since it contributed to lesser amount of reaction over the bed. From the calculations by using the kinetic model, it could be seen that the actual temperatures were higher than the predicted temperatures. The increase in WABTs could also be noticed. These observations can possibly be coupled with nitrogen deactivation of the catalysts. However, more tests are required to verify whether the temperature differences were significant or not. Other parameters which are also important from product selling point of view such as viscosity, color,…

Subjects/Keywords: Catalyst deactivation; Nitrogen deactivation; Hydrotreaters performance; Effect of nitrogen compounds on hydrotreatment; Quasi-irreversible poisoning of hydroprocessing catalysts

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APA (6^th Edition):

HANNAN, K. B. (2014). Organiska kväveföreningars påverkan på vätebehandlingsanläggningens prestanda. (Thesis). KTH. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-172334

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

HANNAN, KHALID BIN. “Organiska kväveföreningars påverkan på vätebehandlingsanläggningens prestanda.” 2014. Thesis, KTH. Accessed March 08, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-172334.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

HANNAN, KHALID BIN. “Organiska kväveföreningars påverkan på vätebehandlingsanläggningens prestanda.” 2014. Web. 08 Mar 2021.

Vancouver:

HANNAN KB. Organiska kväveföreningars påverkan på vätebehandlingsanläggningens prestanda. [Internet] [Thesis]. KTH; 2014. [cited 2021 Mar 08]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-172334.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

HANNAN KB. Organiska kväveföreningars påverkan på vätebehandlingsanläggningens prestanda. [Thesis]. KTH; 2014. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-172334

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

14. Wiedemann, S.C.C. Ferrierite-Catalysed Branching of Unsaturated Fatty Acids.

Degree: 2015, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/324940

► The light alkyl branching in isostearic acid (ISAC) imparts it with unique physical properties and functionalities among fatty acids, making it a valuable raw material… (more)

▼ The light alkyl branching in isostearic acid (ISAC) imparts it with unique physical properties and functionalities among fatty acids, making it a valuable raw material in the production of lubricants, cosmetics and surface-active agents. Being derived from renewable vegetable oils, ISAC has the potential to become a key oleochemical building block in the growing bio-based industrial sector. However, it can currently be manufactured only as a co-product in the polymerisation of unsaturated acids, utilising swelling clays as catalyst. This leads to product balance issues, and a costly purification process. A more selective route to alkyl isomerisation (branching) of unsaturated fatty acids would lower production costs and open up new markets and applications. The prospect of a direct route has recently moved closer, when ferrierite, a medium-pore zeolite, was found to be an effective catalyst in its acid form (H-FER) for the isomerisation of oleic acid (OA), resulting in a step change in the yield of branched unsaturated fatty acids. The goal of this study is to understand the relationship between ferrierite structure and performance, in order to further improve the selectivity, activity and robustness of the zeolite, and thus enable optimisation of the catalytic process for the industrial production of ISAC. To better understand catalyst deactivation, the formation and nature of “coke” species have been studied during the H-FER-catalysed isomerisation of OA. UV-Vis and FT-IR spectroscopic analyses of the spent catalyst materials, complemented by NMR and mass spectrometry analyses of the carbonaceous deposits extract, provide new insights into the deactivation mechanisms. The initial, high catalyst activity is quickly lost, despite conservation of the framework integrity. Dodecyl benzene is the major “coke” constituent, while polyenylic carbocations poison the active sites. Pore blockage is detected very early in the reaction, and only the pore mouth is actively employed. Large zeolite crystals were studied to get more detailed spatial insight into deactivation of ferrierite in the OA alkyl isomerisation, using a combination of visible micro-spectroscopy and fluorescence microscopy. The limited activity observed is in line with the pore mouth catalysis hypothesis; the visible micro-spectroscopy data furthermore shows that the accumulation of aromatic species associated with deactivation (and therefore the reaction) is limited to the crystal edges. Fluorescence microscopy data strongly suggest the presence of polyenylic carbocations, and light polarisation reveals that these carbonaceous species are aligned only in the larger 10-membered ring (10-MR) channels of ferrierite at all crystal edges; the reaction is thus further limited to these specific pore mouths. Finally, a study of the relationship between bulk acidity and performance is reported for five commercial ferrierite catalysts; significant differences were found, independently of their bulk Si/Al ratios. Initial pore conversion correlates with Brønsted acidity… Advisors/Committee Members: Weckhuysen, Bert, Bruijnincx, Pieter.

Subjects/Keywords: Oleochemistry; Isostearic acid; Isomerisation; Ferrierite; Pore mouth; Catalysis; Deactivation; Micro-spectroscopy

11 more images…

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APA (6^th Edition):

Wiedemann, S. C. C. (2015). Ferrierite-Catalysed Branching of Unsaturated Fatty Acids. (Doctoral Dissertation). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/324940

Chicago Manual of Style (16^th Edition):

Wiedemann, S C C. “Ferrierite-Catalysed Branching of Unsaturated Fatty Acids.” 2015. Doctoral Dissertation, Universiteit Utrecht. Accessed March 08, 2021. http://dspace.library.uu.nl:8080/handle/1874/324940.

MLA Handbook (7^th Edition):

Wiedemann, S C C. “Ferrierite-Catalysed Branching of Unsaturated Fatty Acids.” 2015. Web. 08 Mar 2021.

Vancouver:

Wiedemann SCC. Ferrierite-Catalysed Branching of Unsaturated Fatty Acids. [Internet] [Doctoral dissertation]. Universiteit Utrecht; 2015. [cited 2021 Mar 08]. Available from: http://dspace.library.uu.nl:8080/handle/1874/324940.

Council of Science Editors:

Wiedemann SCC. Ferrierite-Catalysed Branching of Unsaturated Fatty Acids. [Doctoral Dissertation]. Universiteit Utrecht; 2015. Available from: http://dspace.library.uu.nl:8080/handle/1874/324940

15. Fonseca, Juliano Roldan. Avaliação dos processos de pré-tratamento da superfície da sílica fundida no preparo de colunas capilares inertes para cromatografia gasosa.

Degree: Mestrado, Química Analítica, 2009, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/75/75132/tde-25082009-093037/ ;

►

O controle da superfície química em colunas capilares abertas é de fundamental importância para atingir um alto desempenho na análise cromatográfica, sendo muito estudada ao… (more)

▼

O controle da superfície química em colunas capilares abertas é de fundamental importância para atingir um alto desempenho na análise cromatográfica, sendo muito estudada ao longo das décadas de 70 e 80, mas tendo pouco destaque nos últimos anos por parte dos pesquisadores. A atividade da superfície de uma coluna capilar é causada por grupos silanol (Si-OH) e impurezas como metais, por exemplo. A presença destes grupos silanol faz com que alguns compostos sofram adsorção, principalmente pela formação de pontes de hidrogênio, originando picos com longas caudas no cromatograma. Por isso, a eliminação dos sítios ativos faz-se necessária quando uma amostra apresenta interação com a superfície da coluna. Esta desativação pode ser feita por meio de agentes silanizantes que reagem com os grupos hidroxila. Visto que a maioria dos artigos publicados sobre este assunto envolve colunas de vidro, o presente trabalho estudou os efeitos de cada fase do pré-tratamento de tubos aplicado para as colunas atuais de sílica fundida, verificando os agentes silanizantes HMDS, DPTMDS e TPDMDS que seriam mais adequados para suportar as fases estacionárias OV-73 e OV-17. Também se avaliou o uso de filmes finos de 0,01 , 0,05 e 0,10 ?m de polietileno glicol (PEG) como alternativa para a desativação da parede interna do capilar, o qual mostrou resultados satisfatórios de estabilidade e inatividade.

The control of the inner surface in open tubular capillary columns has fundamental importance to reach a high performance in gas chromatography analysis. It was very studied during 1970´s and 1980´s, but has not interested the researches along last years, not excluding also, the possibility of commercial secrets regarding column preparation. The activity on the surface of capillary column is mainly caused by silanol groups (Si-OH) and impurities such as metal ions and water. These groups favours reversible and irreversible adsorption of polar compounds, which results in tailed peak shapes and incomplete elution from the column. Therefore, the elimination of the active sites is necessary. The deactivation procedures are based on blocking of silanol groups by means of chemical reaction. This present work studied the effects of the surface pretreatment steps applied to fused silica capillary columns. Some silylating agents such as HMDS, DPTMDS and TPDMDS were valued. The coating behavior using OV-73 and OV-17 stationary phases was studied too. Film thickness of 0,01 , 0,05 and 0,10 ?m of poly(ethylene glycol) (PEG) was applied as alternative procedure, showing good stability and column deactivation.

Advisors/Committee Members: Lanças, Fernando Mauro.

Subjects/Keywords: capillary columns; colunas capilares; cromatografia gasosa; deactivation; desativação; gas chromatography

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APA (6^th Edition):

Fonseca, J. R. (2009). Avaliação dos processos de pré-tratamento da superfície da sílica fundida no preparo de colunas capilares inertes para cromatografia gasosa. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/75/75132/tde-25082009-093037/ ;

Chicago Manual of Style (16^th Edition):

Fonseca, Juliano Roldan. “Avaliação dos processos de pré-tratamento da superfície da sílica fundida no preparo de colunas capilares inertes para cromatografia gasosa.” 2009. Masters Thesis, University of São Paulo. Accessed March 08, 2021. http://www.teses.usp.br/teses/disponiveis/75/75132/tde-25082009-093037/ ;.

MLA Handbook (7^th Edition):

Fonseca, Juliano Roldan. “Avaliação dos processos de pré-tratamento da superfície da sílica fundida no preparo de colunas capilares inertes para cromatografia gasosa.” 2009. Web. 08 Mar 2021.

Vancouver:

Fonseca JR. Avaliação dos processos de pré-tratamento da superfície da sílica fundida no preparo de colunas capilares inertes para cromatografia gasosa. [Internet] [Masters thesis]. University of São Paulo; 2009. [cited 2021 Mar 08]. Available from: http://www.teses.usp.br/teses/disponiveis/75/75132/tde-25082009-093037/ ;.

Council of Science Editors:

Fonseca JR. Avaliação dos processos de pré-tratamento da superfície da sílica fundida no preparo de colunas capilares inertes para cromatografia gasosa. [Masters Thesis]. University of São Paulo; 2009. Available from: http://www.teses.usp.br/teses/disponiveis/75/75132/tde-25082009-093037/ ;

University of Michigan

16. Lupescu, Jason Aaron. Pd Model Catalysts: Effects of Aging Environment, Aging Duration and Interrupting Aging with Brief Air Pulses on Lean Pd Redispersion.

Degree: PhD, Chemical Engineering, 2016, University of Michigan

URL: http://hdl.handle.net/2027.42/133379

► The goals of this investigation were to determine how automotive catalyst characteristics were affected by prolonged exposure to a simulated engine exhaust gas environment, and… (more)

▼ The goals of this investigation were to determine how automotive catalyst characteristics were affected by prolonged exposure to a simulated engine exhaust gas environment, and identify opportunities to limit or reverse catalyst deactivation that correlate with conditions achievable on a vehicle. Model Palladium-based powder catalysts supported on ceria-zirconia (Pd/CZO) and 4wt% La2O3 stabilized γ-Al2O3 (Pd/Al) were selected since these are the primary washcoat components of an automotive catalytic converter. The catalysts were deactivated by constant exposure at 700°C in three different aging environments, oxidizing (lean-only), reducing (rich-only) or a 10 minute cycling of each (redox), for up to three different aging durations, 20 minutes, 2 hours or 16 hours. We determined the aging environment severity ranking of these samples aged for 2 hours or more was as follows: redox > rich-only >> lean-only. The reducing aging environment caused strong metal-support interactions (SMSI) that limited gas-phase access to the Pd surface and dramatically lower catalyst activity, which was much more severe for Pd/CZO catalysts than for Pd/Al catalysts. Dry air treatments applied for 2 hours at 550°C or 700°C showed various degrees of success at reversing SMSI effects, and restoring the fresh-like Pd particle size and catalyst activity depending on the support material, aging duration and dry air temperature. Catalysts with larger average Pd particle size caused by a longer aging duration showed diminishing effects from post-aging dry air treatments, indicating that air should be applied before 20 minutes of aging while the Pd particles were still small. These changes were then made to the redox aging cycle by intermittant replacment of the aging gas with dry air to interrupt the Pd sintering mechanism. Interrupting air pulses on the time scale of a common engine 10 second fuel cut were shown to maintain fresh-like Pd particle size after 16 hours for Pd/Al catalysts, but Pd/CZO catalysts required 10 minute air pulses to achieve the same effect. The insight gained from this work could be used to develop engine control and aftertreatment systems to actively intervene and regenerate a catalyst that is designed to be capable of rapid Pd redispersion. Advisors/Committee Members: Schwank, Johannes W (committee member), Marquis, Emmanuelle (committee member), Ziff, Robert M (committee member), Fisher, Galen B. (committee member), McCabe, Robert W (committee member), Graham, George W (committee member).

Subjects/Keywords: Palladium; Redispersion; Catalyst reactivation; Catalyst deactivation; Chemical Engineering; Engineering

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APA (6^th Edition):

Lupescu, J. A. (2016). Pd Model Catalysts: Effects of Aging Environment, Aging Duration and Interrupting Aging with Brief Air Pulses on Lean Pd Redispersion. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/133379

Chicago Manual of Style (16^th Edition):

Lupescu, Jason Aaron. “Pd Model Catalysts: Effects of Aging Environment, Aging Duration and Interrupting Aging with Brief Air Pulses on Lean Pd Redispersion.” 2016. Doctoral Dissertation, University of Michigan. Accessed March 08, 2021. http://hdl.handle.net/2027.42/133379.

MLA Handbook (7^th Edition):

Lupescu, Jason Aaron. “Pd Model Catalysts: Effects of Aging Environment, Aging Duration and Interrupting Aging with Brief Air Pulses on Lean Pd Redispersion.” 2016. Web. 08 Mar 2021.

Vancouver:

Lupescu JA. Pd Model Catalysts: Effects of Aging Environment, Aging Duration and Interrupting Aging with Brief Air Pulses on Lean Pd Redispersion. [Internet] [Doctoral dissertation]. University of Michigan; 2016. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2027.42/133379.

Council of Science Editors:

Lupescu JA. Pd Model Catalysts: Effects of Aging Environment, Aging Duration and Interrupting Aging with Brief Air Pulses on Lean Pd Redispersion. [Doctoral Dissertation]. University of Michigan; 2016. Available from: http://hdl.handle.net/2027.42/133379

University of Saskatchewan

17. Pacheco Gomez, Francisco 1985-. Mechanism of sulfur poisoning by H2S and SO2 of nickel and cobalt based catalysts for dry reforming of methane.

Degree: 2016, University of Saskatchewan

URL: http://hdl.handle.net/10388/7793

► Nickel catalysts employed in the production of syngas throughout CO2 reforming of CH4 can be poisoned and deactivated by the presence of H2S or SO2… (more)

Subjects/Keywords: CO2 reforming of CH4; Catalyst deactivation; Hydrogen sulfide; Sulfur dioxide; DRIFTS

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APA (6^th Edition):

Pacheco Gomez, F. 1. (2016). Mechanism of sulfur poisoning by H2S and SO2 of nickel and cobalt based catalysts for dry reforming of methane. (Thesis). University of Saskatchewan. Retrieved from http://hdl.handle.net/10388/7793

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Pacheco Gomez, Francisco 1985-. “Mechanism of sulfur poisoning by H2S and SO2 of nickel and cobalt based catalysts for dry reforming of methane.” 2016. Thesis, University of Saskatchewan. Accessed March 08, 2021. http://hdl.handle.net/10388/7793.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Pacheco Gomez, Francisco 1985-. “Mechanism of sulfur poisoning by H2S and SO2 of nickel and cobalt based catalysts for dry reforming of methane.” 2016. Web. 08 Mar 2021.

Vancouver:

Pacheco Gomez F1. Mechanism of sulfur poisoning by H2S and SO2 of nickel and cobalt based catalysts for dry reforming of methane. [Internet] [Thesis]. University of Saskatchewan; 2016. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10388/7793.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pacheco Gomez F1. Mechanism of sulfur poisoning by H2S and SO2 of nickel and cobalt based catalysts for dry reforming of methane. [Thesis]. University of Saskatchewan; 2016. Available from: http://hdl.handle.net/10388/7793

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Penn State University

18. Kim, Kyungsoo. The effect of hydrocarbon structure on nickel catalyst deactivation in steam reforming of hexane and benzene.

Degree: 2013, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/19852

► Steam reforming of hexane and benzene for hydrogen production has been carried out on Ni and Rh catalysts at 800 °C with and without sulfur… (more)

▼ Steam reforming of hexane and benzene for hydrogen production has been carried out on Ni and Rh catalysts at 800 °C with and without sulfur to understand the deactivation mechanisms in steam reforming reactions and how hydrocarbon structure affects the processes. Three catalysts were synthesized using incipient wetness impregnation method: 2% and 10%Ni catalysts supported on 20%CeO2-modified Al2O3 (denoted as “2Ni/CeAl” and “10Ni/CeAl”, respectively), and 2%Rh catalyst supported on the same support (denoted as “2Rh/CeAl”). The 10Ni/CeAl catalyst is the focus of the study, and the 2Ni/CeAl and 2Rh/CeAl catalysts were used as control samples. It is found that catalyst deactivates much faster in hexane reforming than in benzene reforming on 10Ni/CeAl with the presence of sulfur poison. Temperature programmed oxidation (TPO) and X-ray absorption near edge structure (XANES) spectroscopy, transmission electron microscopy (TEM), and X-ray diffraction (XRD) are used together to understand the catalyst deactivation mechanisms and the effects of hydrocarbon structure on catalyst deactivation. Sulfur K-edge XANES measured and estimated the sulfur species formed on the catalyst after steam reforming reaction. The sulfur species formed on the catalyst are the same for benzene and hexane reforming, i.e., Ni sulfide and sulfate, which do not correlate with catalyst deactivation once carbon starts to deposit on the catalyst. Formation of metal sulfide is faster in hexane reforming than in benzene reforming. It is likely that that benzene has higher reactivity with Ni, which leads to delayed sulfur poisoning in benzene reforming. TPO measured the amounts of carbon deposits on metal and support due to their different reactivity toward oxidation. Carbon deposition on the catalyst increases with time in both benzene and hexane reforming. More carbon is formed in hexane reforming than in benzene reforming. Carbon deposition locations are quite different as well. In benzene reforming, more carbon is deposited on the metal while in hexane reforming it is on the contrary. Carbon K-edge XANES measured the structure of carbon deposits on the used catalysts and it is found that the carbon deposits have no significant structural difference in benzene and hexane reforming. However, TEM analysis combined with EDX elemental mapping revealed that there is significant structural difference between carbon formed on the Ni and carbon on the support. Results from both reactions support a carbon deposition mechanism, i.e., carbon is formed on the metal first, and then partially dehydrogenated hydrocarbons formed on metal migrate over to the support to form coke on the support. In summary, the difference in catalyst deactivation of steam reforming over Ni catalyst with the presence of sulfur poison for benzene and hexane reforming is well explained by the metal reactivity with different structured hydrocarbons. The hydrocarbons with higher reactivity (such as benzene) protects the catalyst by delaying the formation of Ni sulfide through more competitive… Advisors/Committee Members: Yongsheng Chen, Dissertation Advisor/Co-Advisor, Yongsheng Chen, Committee Chair/Co-Chair, Caroline Elaine Clifford, Committee Member, Semih Eser, Committee Member, Chunshan Song, Committee Member, Turgay Ertekin, Committee Member, Adrianus C Van Duin, Special Member.

Subjects/Keywords: steam reforming; catalyst; deactivation; hydrocarbon; hexane; benzene; nickel; XANES

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APA (6^th Edition):

Kim, K. (2013). The effect of hydrocarbon structure on nickel catalyst deactivation in steam reforming of hexane and benzene. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/19852

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kim, Kyungsoo. “The effect of hydrocarbon structure on nickel catalyst deactivation in steam reforming of hexane and benzene.” 2013. Thesis, Penn State University. Accessed March 08, 2021. https://submit-etda.libraries.psu.edu/catalog/19852.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kim, Kyungsoo. “The effect of hydrocarbon structure on nickel catalyst deactivation in steam reforming of hexane and benzene.” 2013. Web. 08 Mar 2021.

Vancouver:

Kim K. The effect of hydrocarbon structure on nickel catalyst deactivation in steam reforming of hexane and benzene. [Internet] [Thesis]. Penn State University; 2013. [cited 2021 Mar 08]. Available from: https://submit-etda.libraries.psu.edu/catalog/19852.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kim K. The effect of hydrocarbon structure on nickel catalyst deactivation in steam reforming of hexane and benzene. [Thesis]. Penn State University; 2013. Available from: https://submit-etda.libraries.psu.edu/catalog/19852

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Penn State University

19. Xie, Chao. UNDERSTANDING OF CATALYST DEACTIVATION CAUSED BY SULFUR POISONING AND CARBON DEPOSITION IN STEAM REFORMING OF LIQUID HYDROCARBON FUELS.

Degree: 2011, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/11752

► The present work was conducted to develop a better understanding on the catalyst deactivation in steam reforming of sulfur-containing liquid hydrocarbon fuels for hydrogen production.… (more)

▼ The present work was conducted to develop a better understanding on the catalyst deactivation in steam reforming of sulfur-containing liquid hydrocarbon fuels for hydrogen production. Steam reforming of Norpar13 (a liquid hydrocarbon fuel from Exxon Mobile) without and with sulfur was performed on various metal catalysts (Rh, Ru, Pt, Pd, and Ni) supported on different materials (Al2O3, CeO2, SiO2, MgO, and CeO2-Al2O3). A number of characterization techniques were applied to study the physicochemical properties of these catalysts before and after the reactions. Especially, X-ray absorption near edge structure (XANES) spectroscopy was intensively used to investigate the nature of sulfur and carbon species in the used catalysts to reveal the catalyst deactivation mechanism. Among the tested noble metal catalysts (Rh, Ru, Pt, and Pd), Rh catalyst is the most sulfur tolerant. Al2O3 and CeO2 are much better than SiO2 and MgO as the supports for the Rh catalyst to reform sulfur-containing hydrocarbons. The good sulfur tolerance of Rh/Al2O3 can be attributed to the acidic nature of the Al2O3 support and its small Rh crystallites (1-3 nm) as these characteristics facilitate the formation of electron-deficient Rh particles with high sulfur tolerance. The good catalytic performance of Rh/CeO2 in the presence of sulfur can be ascribed to the promotion effect of CeO2 on carbon gasification, which significantly reduced the carbon deposition on the Rh/CeO2catalyst. Steam reforming of Norpar13 in the absence and presence of sulfur was further carried out over CeO2-Al2O3 supported monometallic Ni and Rh and bimetallic Rh-Ni catalysts at 550 and 800 °C. Both monometallic catalysts rapidly deactivated at 550 °C, and showed poor sulfur tolerance. Although ineffective for the Ni catalyst, increasing the temperature to 800 °C dramatically improved the sulfur tolerance of the Rh catalyst. Sulfur K-edge XANES revealed that metal sulfide and organic sulfide are the dominant sulfur species on the used Ni catalyst, while sulfonate and sulfate predominate on the used Rh catalyst. The superior sulfur tolerance of the Rh/CeO2-Al2O3 catalyst at 800 °C may be associated with its capability in sulfur oxidation. It is very likely that the oxygen-shielded sulfur structure of sulfonate and sulfate can suppress the poisoning impact of sulfur on Rh through inhibiting direct rhodium-sulfur interaction. Although the Rh-Ni catalyst exhibited better sulfur tolerance than the monometallic ones at 550 °C, its catalytic performance was inferior compared with the Rh catalyst in the sulfur-containing reaction at 800 °C probably due to the severe carbon deposition on the bimetallic catalyst. The last part of this work focuses on the influence of sulfur on the carbon deposition in steam reforming of liquid hydrocarbon fuels over CeO2-Al2O3 supported monometallic Ni and Rh catalysts at 800 ºC. Though abundant carbon deposits can accumulate on the pure CeO2-Al2O3 support due to fuel thermal cracking, the metal addition substantially mitigated the carbon deposition in… Advisors/Committee Members: Chunshan Song, Dissertation Advisor/Co-Advisor, Chunshan Song, Committee Chair/Co-Chair, Yongsheng Chen, Committee Member, Andre Louis Boehman, Committee Member, Michael John Janik, Committee Member.

Subjects/Keywords: Hydrogen; reforming; Nickel; Rhodium; Deactivation; Sulfur poisoning; Carbon deposition

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APA (6^th Edition):

Xie, C. (2011). UNDERSTANDING OF CATALYST DEACTIVATION CAUSED BY SULFUR POISONING AND CARBON DEPOSITION IN STEAM REFORMING OF LIQUID HYDROCARBON FUELS. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/11752

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Xie, Chao. “UNDERSTANDING OF CATALYST DEACTIVATION CAUSED BY SULFUR POISONING AND CARBON DEPOSITION IN STEAM REFORMING OF LIQUID HYDROCARBON FUELS.” 2011. Thesis, Penn State University. Accessed March 08, 2021. https://submit-etda.libraries.psu.edu/catalog/11752.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Xie, Chao. “UNDERSTANDING OF CATALYST DEACTIVATION CAUSED BY SULFUR POISONING AND CARBON DEPOSITION IN STEAM REFORMING OF LIQUID HYDROCARBON FUELS.” 2011. Web. 08 Mar 2021.

Vancouver:

Xie C. UNDERSTANDING OF CATALYST DEACTIVATION CAUSED BY SULFUR POISONING AND CARBON DEPOSITION IN STEAM REFORMING OF LIQUID HYDROCARBON FUELS. [Internet] [Thesis]. Penn State University; 2011. [cited 2021 Mar 08]. Available from: https://submit-etda.libraries.psu.edu/catalog/11752.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Xie C. UNDERSTANDING OF CATALYST DEACTIVATION CAUSED BY SULFUR POISONING AND CARBON DEPOSITION IN STEAM REFORMING OF LIQUID HYDROCARBON FUELS. [Thesis]. Penn State University; 2011. Available from: https://submit-etda.libraries.psu.edu/catalog/11752

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Texas A&M University

20. Rojas, Pedro. Kinetic Modeling of the Hydrocracking of Fused-Ring Di-Aromatic Species.

Degree: PhD, Chemical Engineering, 2015, Texas A&M University

URL: http://hdl.handle.net/1969.1/154973

► The derivation of kinetic models for the development and simulation of hydrocarbon processes require detailed information on the reaction network. In the present work, experiments… (more)

▼ The derivation of kinetic models for the development and simulation of hydrocarbon processes require detailed information on the reaction network. In the present work, experiments on the hydrocracking of fused-ring species, specifically naphthalene and 1-methylnaphthalene were performed. The feed was diluted with n-heptane, and the experiments were conducted in a fixed bed catalytic reactor loaded with Pt/Pd HY zeolite catalyst in the temperature range 275 °C to 350 °C, at pressures between 28 and 35 bar, space times between 21 to 144 gcat h/mol of reactant and with hydrogen/hydrocarbon molar ratios ranging from 100 to 340. With naphthalene as the feed as many as 16 components were detected and identified in the reactor effluent, with 1-methylnaphthalene up to 42. The effect of catalyst deactivation on the rates of different reactions and elementary steps was studied, and the effects of temperature, pressure and space time on the product distribution in the absence of catalyst deactivation were observed. Following the rules of carbenium ion chemistry detailed networks in terms of elementary steps were generated for each feed species. The network for naphthalene contains a total of 16 reactions on the metal sites and 46 elementary steps on the acid sites, that for 1-methylnaphthalene 123 reactions on the metal sites and 258 elementary steps on the acid sites. Typical pathways to a given product include dehydrogenation/hydrogenation of ring structures on the metal sites and protonation/deprotonation, ring contraction/expansion, PCP branching of side chains, and endocyclic β-scission on the acid sites. The presence of Pt in the catalyst also led to side chain and ring-opening hydrogenolysis. The single-event modeling approach aimed to reduce the number of independent parameters to be determined from the experimental data for the large number of reactions and elementary steps in the networks. The frequency factors on the acid sites were modeled using single-event kinetics and the activation energies using Evans-Polanyi relationship. On the metal sites the nature of the reacting species and the type of reaction determined the number of parameters. The kinetic model contains hundreds of parameters. Of those, there are only 25 independent parameters for steps on the acid sites, and 16 independent parameters for reactions on the metal sites. An optimization strategy was developed by the sequential use of three different optimization methods to fit the experimental data. Advisors/Committee Members: Froment, Gilbert F (advisor), Balbuena, Perla (committee member), Barrufet, Maria (committee member), Hall, Kenneth (committee member).

Subjects/Keywords: Kinetics; Single-events; Hydrocracking; Catalyst deactivation; Naphthalene; 1-Methylnaphthalene

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APA (6^th Edition):

Rojas, P. (2015). Kinetic Modeling of the Hydrocracking of Fused-Ring Di-Aromatic Species. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/154973

Chicago Manual of Style (16^th Edition):

Rojas, Pedro. “Kinetic Modeling of the Hydrocracking of Fused-Ring Di-Aromatic Species.” 2015. Doctoral Dissertation, Texas A&M University. Accessed March 08, 2021. http://hdl.handle.net/1969.1/154973.

MLA Handbook (7^th Edition):

Rojas, Pedro. “Kinetic Modeling of the Hydrocracking of Fused-Ring Di-Aromatic Species.” 2015. Web. 08 Mar 2021.

Vancouver:

Rojas P. Kinetic Modeling of the Hydrocracking of Fused-Ring Di-Aromatic Species. [Internet] [Doctoral dissertation]. Texas A&M University; 2015. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/1969.1/154973.

Council of Science Editors:

Rojas P. Kinetic Modeling of the Hydrocracking of Fused-Ring Di-Aromatic Species. [Doctoral Dissertation]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/154973

KTH

21. Jonsson, Daniel. Evaluation of Non-Noble Metal Catalysts for CO Oxidation.

Degree: Chemical Science and Engineering (CHE), 2016, KTH

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207363

► The aim of the study is to evaluate the ability of non-noble metal catalysts to function as the commercially used noble metal catalyst. The… (more)

Subjects/Keywords: CO oxidation; sulfur; deactivation; catalysis; CuO; Chemical Engineering; Kemiteknik

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APA (6^th Edition):

Jonsson, D. (2016). Evaluation of Non-Noble Metal Catalysts for CO Oxidation. (Thesis). KTH. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207363

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Jonsson, Daniel. “Evaluation of Non-Noble Metal Catalysts for CO Oxidation.” 2016. Thesis, KTH. Accessed March 08, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207363.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Jonsson, Daniel. “Evaluation of Non-Noble Metal Catalysts for CO Oxidation.” 2016. Web. 08 Mar 2021.

Vancouver:

Jonsson D. Evaluation of Non-Noble Metal Catalysts for CO Oxidation. [Internet] [Thesis]. KTH; 2016. [cited 2021 Mar 08]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207363.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Jonsson D. Evaluation of Non-Noble Metal Catalysts for CO Oxidation. [Thesis]. KTH; 2016. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-207363

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Iowa

22. O'Toole, Ann Marie. Thermal deactivation of Pseudomonas aeruginosa biofilms.

Degree: MS, Chemical and Biochemical Engineering, 2015, University of Iowa

URL: https://ir.uiowa.edu/etd/1715

► Bacterial biofilm infection is a common (~ 2 to 4%) complication for recipients of surgically implanted medical devices. Due to the tremendous increase in… (more)

Subjects/Keywords: publicabstract; Biofilm; Pseudomonas aeruginosa; Thermal deactivation; Chemical Engineering

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APA (6^th Edition):

O'Toole, A. M. (2015). Thermal deactivation of Pseudomonas aeruginosa biofilms. (Masters Thesis). University of Iowa. Retrieved from https://ir.uiowa.edu/etd/1715

Chicago Manual of Style (16^th Edition):

O'Toole, Ann Marie. “Thermal deactivation of Pseudomonas aeruginosa biofilms.” 2015. Masters Thesis, University of Iowa. Accessed March 08, 2021. https://ir.uiowa.edu/etd/1715.

MLA Handbook (7^th Edition):

O'Toole, Ann Marie. “Thermal deactivation of Pseudomonas aeruginosa biofilms.” 2015. Web. 08 Mar 2021.

Vancouver:

O'Toole AM. Thermal deactivation of Pseudomonas aeruginosa biofilms. [Internet] [Masters thesis]. University of Iowa; 2015. [cited 2021 Mar 08]. Available from: https://ir.uiowa.edu/etd/1715.

Council of Science Editors:

O'Toole AM. Thermal deactivation of Pseudomonas aeruginosa biofilms. [Masters Thesis]. University of Iowa; 2015. Available from: https://ir.uiowa.edu/etd/1715

23. Vogelaar, B.M. Deactivation of Hydroprocessing Catalysts: New insights in catalyst structure, activity and stability.

Degree: 2005, Ponsen & Looijen B.V., Wageningen

URL: http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30

► In dit proefschrift is de deactivering van hydroprocessing katalysatoren onderzocht. Katalysatoren zijn hulpstoffen die gebruikt worden om chemische reacties te bewerkstelligen, zonder daarbij zelf verbruikt… (more)

▼ In dit proefschrift is de deactivering van hydroprocessing katalysatoren onderzocht. Katalysatoren zijn hulpstoffen die gebruikt worden om chemische reacties te bewerkstelligen, zonder daarbij zelf verbruikt te worden. Een bekend voorbeeld is de uitlaatkatalysator in de auto, die o.a. onverbrande brandstofresten omzet in kooldioxide en water. In de chemische industrie worden verschillende katalysatoren toegepast voor diverse processen. Deze katalysatoren zijn veelal aangebracht op een vaste drager (bijvoorbeeld korrels), en bevatten metalen als aktieve component. Hydroprocessing is zo’n katalytisch proces, gebruikt in de olieraffinage voor de produktie van schone benzine en diesel. Om de uitstoot van schadelijke stoffen te beperken moeten benzine en diesel aan steeds strengere eisen voldoen. Eén daarvan is het zwavelgehalte, dat de komende jaren moet worden verlaagd tot 0.005%. Aardolie bevat zwavelhoudende componenten en deze kunnen in de produkten (brandstoffen) terechtkomen. In de motor wordt zwavel omgezet in SOx, een belangrijke veroorzaker van zure regen. De meest effectieve manier om dit te voorkomen is het reduceren van de hoeveelheid zwavel in de brandstof. Dit doen de meeste olieraffinaderijen met behulp van hydrodesulfurization (HDS) ofwel hydroprocessing. Het proces maakt gebruik van waterstof (H2) om selectief de zwavelcomponenten om te zetten in “schone” koolwaterstoffen en zwavel-waterstofgas (H2S). Dit gebeurt met behulp van een hydroprocessing katalysator, bij hoge temperatuur en druk. De gevormde H2S wordt afgescheiden van de ontzwavelde brandstof, en omgezet in vaste zwavel voor diverse doeleinden. In tegenstelling tot wat de bovenstaande definitie doet vermoeden, hebben katalysatoren niet het eeuwige leven. Hun aktiviteit neemt langzaam af door deactivering, tot een punt wordt bereikt waarop de katalysator moet worden ververst. Dit geldt ook voor hydroprocessing katalysatoren, die gemiddeld 2 jaar meegaan. Het doel van dit onderzoek is het vaststellen van de belangrijkste oorzaken van deactivering. Bovendien willen we beter begrijpen hoe de katalysator werkt. Het beantwoorden van deze vragen kan helpen bij de ontwikkeling van katalysatoren met een betere werking en langere levensduur, nodig voor het halen van de toekomstige brandstofspecificaties. Conventionele hydroprocessing katalysatoren bevatten molybdeensulfide (MoS2) op een poreuze alumina drager (Al2O3). Meestal wordt nikkel (Ni) of cobalt (Co) toegevoegd als promoter, waardoor de aktiviteit van de katalysator sterk toeneemt. De resulterende aktieve component of aktieve fase wordt CoMoS of NiMoS genoemd. Deze fase heeft een gelaagde struktuur, bestaande uit steeds een laag molybdeen atomen tussen twee lagen zwavelatomen. Deze zwavelatomen schermen het aktieve metaal (molybdeen) af, waardoor geen reacties kunnen plaatsvinden. Echter, aan de randen van deze struktuur kunnen zwavelatomen ontbreken, waardoor op die plaatsen de reactie wél mogelijk is. De atomen van de promoter (Ni of Co) nemen vermoedelijk een plaats in aan deze randen. Omdat… Advisors/Committee Members: Moulijn, J.A..

Subjects/Keywords: Chemical engineering; Catalysis; Hydroprocessing; Deactivation

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APA (6^th Edition):

Vogelaar, B. M. (2005). Deactivation of Hydroprocessing Catalysts: New insights in catalyst structure, activity and stability. (Doctoral Dissertation). Ponsen & Looijen B.V., Wageningen. Retrieved from http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30

Chicago Manual of Style (16^th Edition):

Vogelaar, B M. “Deactivation of Hydroprocessing Catalysts: New insights in catalyst structure, activity and stability.” 2005. Doctoral Dissertation, Ponsen & Looijen B.V., Wageningen. Accessed March 08, 2021. http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30.

MLA Handbook (7^th Edition):

Vogelaar, B M. “Deactivation of Hydroprocessing Catalysts: New insights in catalyst structure, activity and stability.” 2005. Web. 08 Mar 2021.

Vancouver:

Vogelaar BM. Deactivation of Hydroprocessing Catalysts: New insights in catalyst structure, activity and stability. [Internet] [Doctoral dissertation]. Ponsen & Looijen B.V., Wageningen; 2005. [cited 2021 Mar 08]. Available from: http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30.

Council of Science Editors:

Vogelaar BM. Deactivation of Hydroprocessing Catalysts: New insights in catalyst structure, activity and stability. [Doctoral Dissertation]. Ponsen & Looijen B.V., Wageningen; 2005. Available from: http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; urn:NBN:nl:ui:24-uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30 ; http://resolver.tudelft.nl/uuid:1f5f31e7-b83a-4b49-b622-bb461ae19d30

University of Notre Dame

24. Allison Janette Cross. Catalyst Design for Hydrogen Production from Ethanol</h1>.

Degree: Chemical Engineering, 2014, University of Notre Dame

URL: https://curate.nd.edu/show/xk81jh36q15

► To further a sustainable energy future, hydrogen to be used in fuel cell applications is required as an alternative to non-renewable resources. In this… (more)

▼ To further a sustainable energy future, hydrogen to be used in fuel cell applications is required as an alternative to non-renewable resources. In this thesis, catalysts for hydrogen production from ethanol were designed and characterized to draw correlations between the chemistry and structure of said catalysts and their activity, selectivity, and lifetime during ethanol dehydrogenation. Specifically, Impregnated Support Combustion Synthesis (ISCS) is used as a technique to prepare Ni supported catalysts for hydrogen production. The formation of unsupported metallic Ni catalysts by SCS is studied (Chapter 3). It was determined that the mechanism of metal formation in the combustion front is due to reduction by gases released during the combustion reaction when producing bulk Ni catalysts. In Chapter 4, ISCS is used to prepare Ni supported on alumina pellets to enhance the properties of the catalyst, increasing activity for ethanol decomposition at lower temperatures as compared to the bulk unsupported Ni catalysts. Ni catalysts prepared by ISCS are also supported on ceria and silica powders (Chapter 5) to determine the effect of supports on the activity and selectivity of the catalysts. In-situ techniques are employed to correlate the chemistry and structure of the catalysts near reaction conditions to their performance during reaction. Lastly, the stability towards deactivation of these Ni supported catalysts, as well as newly designed catalysts, is described (Chapter 6). UHV-XPS and TEM images before and after reaction are used to determine the causes of deactivation during ethanol decomposition. It was found that carbon formation heavily affected the catalysts? activity during extended periods of reaction, and to prevent deactivation, a partial encapsulation of the active metal by the support was necessary. Advisors/Committee Members: Eduardo Wolf, Committee Chair, Jason Hicks, Committee Member, Bill Schneider, Committee Member, Basar Bilgicer, Committee Member, Alexander Mukasyan, Committee Co-Chair.

Subjects/Keywords: hydrogen production; heterogeneous catalysis; combustion synthesis; carbon formation deactivation

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APA (6^th Edition):

Cross, A. J. (2014). Catalyst Design for Hydrogen Production from Ethanol</h1>. (Thesis). University of Notre Dame. Retrieved from https://curate.nd.edu/show/xk81jh36q15

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Cross, Allison Janette. “Catalyst Design for Hydrogen Production from Ethanol</h1>.” 2014. Thesis, University of Notre Dame. Accessed March 08, 2021. https://curate.nd.edu/show/xk81jh36q15.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Cross, Allison Janette. “Catalyst Design for Hydrogen Production from Ethanol</h1>.” 2014. Web. 08 Mar 2021.

Vancouver:

Cross AJ. Catalyst Design for Hydrogen Production from Ethanol</h1>. [Internet] [Thesis]. University of Notre Dame; 2014. [cited 2021 Mar 08]. Available from: https://curate.nd.edu/show/xk81jh36q15.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cross AJ. Catalyst Design for Hydrogen Production from Ethanol</h1>. [Thesis]. University of Notre Dame; 2014. Available from: https://curate.nd.edu/show/xk81jh36q15

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Michigan Technological University

25. Parker, Zakarie. EFFECTS OF VARIABLE VALVE ACTUATION ON EXHAUST ENTHALPY AND ENGINE OUT EMISSIONS.

Degree: MS, Department of Mechanical Engineering-Engineering Mechanics, 2019, Michigan Technological University

URL: https://digitalcommons.mtu.edu/etdr/883

► Vehicle emissions standards are becoming increasingly more strict as time progresses. Once all of the emissions devices are in their operational stage, these standards… (more)

Subjects/Keywords: catalyst heating; emissions; startup; valve deactivation; camshaft duration; Automotive Engineering

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APA (6^th Edition):

Parker, Z. (2019). EFFECTS OF VARIABLE VALVE ACTUATION ON EXHAUST ENTHALPY AND ENGINE OUT EMISSIONS. (Masters Thesis). Michigan Technological University. Retrieved from https://digitalcommons.mtu.edu/etdr/883

Chicago Manual of Style (16^th Edition):

Parker, Zakarie. “EFFECTS OF VARIABLE VALVE ACTUATION ON EXHAUST ENTHALPY AND ENGINE OUT EMISSIONS.” 2019. Masters Thesis, Michigan Technological University. Accessed March 08, 2021. https://digitalcommons.mtu.edu/etdr/883.

MLA Handbook (7^th Edition):

Parker, Zakarie. “EFFECTS OF VARIABLE VALVE ACTUATION ON EXHAUST ENTHALPY AND ENGINE OUT EMISSIONS.” 2019. Web. 08 Mar 2021.

Vancouver:

Parker Z. EFFECTS OF VARIABLE VALVE ACTUATION ON EXHAUST ENTHALPY AND ENGINE OUT EMISSIONS. [Internet] [Masters thesis]. Michigan Technological University; 2019. [cited 2021 Mar 08]. Available from: https://digitalcommons.mtu.edu/etdr/883.

Council of Science Editors:

Parker Z. EFFECTS OF VARIABLE VALVE ACTUATION ON EXHAUST ENTHALPY AND ENGINE OUT EMISSIONS. [Masters Thesis]. Michigan Technological University; 2019. Available from: https://digitalcommons.mtu.edu/etdr/883

University of Arizona

26. Hinckley, Adam. Activation and Deactivation of Semiconductor Surfaces .

Degree: 2019, University of Arizona

URL: http://hdl.handle.net/10150/636688

► The development of surface modification techniques is an integral part of advancing semiconductor device fabrication beyond subtractive methods. Chemically altering surfaces to be more or… (more)

▼ The development of surface modification techniques is an integral part of advancing semiconductor device fabrication beyond subtractive methods. Chemically altering surfaces to be more or less reactive can eliminate steps in production to form devices quicker and with less material waste. This doctoral dissertation presents a series of work dedicated to improving our understanding of various techniques of surface modification and developing processes that enhance the utility of existing methods. Self-assembled monolayers (SAMs) made from octadecyltrichlorosilane (OTS) are implemented for surface deactivation and defects are studied. Defective areas in SAMs limit their utility in device production and are notoriously difficult to eliminate. However, the addition of intermediate cleaning steps are shown to prevent defects to deactivate the growth of 10 nm TiO2 films by atomic layer deposition (ALD). Spectroscopic ellipsometry, goniometry, and x-ray photoelectron spectroscopy (XPS) are used to examine SAMs deposited using different cleaning steps and assess their ability to act as an ALD resist. Polar and non-polar agglomerates adsorbed to the SAM are removed by solvent extraction and aqueous cleaning in series, and defect free layers are deposited by a second liquid phase immersion. Atomic force microscopy (AFM) confirmed the removal of agglomerates so that OTS coated SiO2 surfaces were as smooth as clean SiO2, producing deactivated surfaces suitable for prototype devices. Intermediate cleaning steps were applied to OTS deposition to reduce immersion times from 24 h to 1 h and SAMs were analyzed with XPS. Peaks shown in O 1s regions indicating the presence of surface hydroxyls showed that immersion in SC-1 (NH4OH:H2O2:H2O) doubled hydroxyl concentration on the substrate while OTS surface coverage was left relatively unchanged. In addition to the removal of polar agglomerates from the SAM surface, SC-1 hydroxylates pinhole defects in the SAM to re-activate the underlying substrate for additional deposition. A second OTS deposition improved surface coverage to cover nearly every active site on the substrate to form defect-free layers. Exposure to 200 cycles of TiO2 ALD using TiCl4 and H2O confirmed that no defects were present, as afterwards Ti was not detected on the surface by XPS. Layers were patterned with conductive mode AFM to form open trenches approximately 160 nm wide within the SAM for area selective deposition. Approximately 8 nm of TiO2 was selectively deposited within trenches while no significant deposition was noted outside trenches to demonstrate an area-selective ALD process. Indirect surface modification is also demonstrated by altering ALD precursors and implementing in-situ cleaning steps. Aluminum oxide was grown using both water and peroxide as oxidants and resulting films were analyzed and compared using XPS. Peaks in the O 1s and Al 2p regions monitored the formation of the Al-O bond and found that film nucleation occurred quicker with a higher coverage of Al when using peroxide as an oxidant.… Advisors/Committee Members: Muscat, Anthony J (advisor), Shadman, Farhang (committeemember), Gervasio, Dominic (committeemember), Raghavan, Srini (committeemember).

Subjects/Keywords: atomic layer deposition; defect detection; organosilane; Surface deactivation

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APA (6^th Edition):

Hinckley, A. (2019). Activation and Deactivation of Semiconductor Surfaces . (Doctoral Dissertation). University of Arizona. Retrieved from http://hdl.handle.net/10150/636688

Chicago Manual of Style (16^th Edition):

Hinckley, Adam. “Activation and Deactivation of Semiconductor Surfaces .” 2019. Doctoral Dissertation, University of Arizona. Accessed March 08, 2021. http://hdl.handle.net/10150/636688.

MLA Handbook (7^th Edition):

Hinckley, Adam. “Activation and Deactivation of Semiconductor Surfaces .” 2019. Web. 08 Mar 2021.

Vancouver:

Hinckley A. Activation and Deactivation of Semiconductor Surfaces . [Internet] [Doctoral dissertation]. University of Arizona; 2019. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10150/636688.

Council of Science Editors:

Hinckley A. Activation and Deactivation of Semiconductor Surfaces . [Doctoral Dissertation]. University of Arizona; 2019. Available from: http://hdl.handle.net/10150/636688

University of Waterloo

27. Russell, April Elizabeth. Spatial Temperature and Concentration Changes Following Heterogeneous Damage To a Model Diesel Oxidation Catalyst.

Degree: 2010, University of Waterloo

URL: http://hdl.handle.net/10012/5643

► Infra-Red thermography and spatially-resolved capillary inlet mass spectrometry (SpaciMS) have been used to characterize propylene oxidation along a Pt/Al2O3 monolith-supported catalyst, before and after heterogeneous… (more)

Subjects/Keywords: Diesel oxidation catalyst; deactivation

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APA (6^th Edition):

Russell, A. E. (2010). Spatial Temperature and Concentration Changes Following Heterogeneous Damage To a Model Diesel Oxidation Catalyst. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/5643

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Russell, April Elizabeth. “Spatial Temperature and Concentration Changes Following Heterogeneous Damage To a Model Diesel Oxidation Catalyst.” 2010. Thesis, University of Waterloo. Accessed March 08, 2021. http://hdl.handle.net/10012/5643.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Russell, April Elizabeth. “Spatial Temperature and Concentration Changes Following Heterogeneous Damage To a Model Diesel Oxidation Catalyst.” 2010. Web. 08 Mar 2021.

Vancouver:

Russell AE. Spatial Temperature and Concentration Changes Following Heterogeneous Damage To a Model Diesel Oxidation Catalyst. [Internet] [Thesis]. University of Waterloo; 2010. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10012/5643.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Russell AE. Spatial Temperature and Concentration Changes Following Heterogeneous Damage To a Model Diesel Oxidation Catalyst. [Thesis]. University of Waterloo; 2010. Available from: http://hdl.handle.net/10012/5643

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Canterbury

28. Oparah, Irene A. Photosynthetic acclimation to temperature of four Eucalyptus species and Sequoia sempervirens.

Degree: Master of Forestry Science, Forestry, 2012, University of Canterbury

URL: http://dx.doi.org/10.26021/1276

► The 3-PG physiological/mensurational hybrid model is a useful forest management tool capable of producing accurate growth results across a number of parameterised species. The temperature… (more)

▼ The 3-PG physiological/mensurational hybrid model is a useful forest management tool capable of producing accurate growth results across a number of parameterised species. The temperature data used in the model are the average maximum and minimum values for photosynthesis above the compensation point (Landsberg and Sands 2011). There is a minimum temperature below which positive net CO₂ exchange will not occur, a maximum temperature above which it will not occur and an optimum temperature at which it is maximised. These parameters are used in the 3-PG physiological model of forest production. However, a species’ photosynthetic response to short-term variation may differ from one season to another as species acclimate to temperatures over periods of a few weeks. In this study, acclimation responses of four species of eucalypt and Sequoia sempervirens to long-term temperatures were studied over a wide range of short-term temperature changes in order to identify the minimum, optimum and maximum temperatures of CO₂ assimilation for physiological/mensurational hybrid modelling, and also to identify the sites for which the species would be best suited. In order to achieve the aims of this study, a growth chamber experiment was established. Seedlings of four eucalypt species and Sequoia sempervirens were grown at base-line day/night temperatures of 30/16, 22/12 and 10/5ºC in controlled environment chambers for three months and leaf gas exchange measurements were made of the species at seven short-term temperature levels (5, 10, 15, 20, 25, 30 and 35ºC). The optimum and the maximum temperatures for net photosynthesis increased with an increase in base-line temperature for all species. The highest optimum temperature and net photosynthetic rates recorded were in plants grown at 30/16ºC and the lowest were in those grown at 10/5ºC. The maximum rate of net CO₂ assimilation increased with the temperature at which plants were grown partly because of acclimation in key photosynthetic processes in the Calvin cycle. Responses of maximal carboxylation rate (Vcmax) and also the maximal light-driven electron flux (Jmax) to short-term temperature change varied with base-line temperature for all species studied. Net photosynthesis and photosynthetic parameters measured did not vary significantly with effects of nitrogen, phosphorus and their interaction (p = 0.1468). The ratio of Jmax to Vcmax decreased with increasing leaf temperatures for all species (p < 0.001). These results indicate that the species studied will adapt to long-run changes in temperature, and the parameters obtained from these studies can be used for models that simulate the physiology and growth of the species.

Subjects/Keywords: Photosynthesis; acclimation; eucalyptus; Sequoia sempervirens; Jmax; Vcmax; activation energy; deactivation energy

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APA (6^th Edition):

Oparah, I. A. (2012). Photosynthetic acclimation to temperature of four Eucalyptus species and Sequoia sempervirens. (Masters Thesis). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/1276

Chicago Manual of Style (16^th Edition):

Oparah, Irene A. “Photosynthetic acclimation to temperature of four Eucalyptus species and Sequoia sempervirens.” 2012. Masters Thesis, University of Canterbury. Accessed March 08, 2021. http://dx.doi.org/10.26021/1276.

MLA Handbook (7^th Edition):

Oparah, Irene A. “Photosynthetic acclimation to temperature of four Eucalyptus species and Sequoia sempervirens.” 2012. Web. 08 Mar 2021.

Vancouver:

Oparah IA. Photosynthetic acclimation to temperature of four Eucalyptus species and Sequoia sempervirens. [Internet] [Masters thesis]. University of Canterbury; 2012. [cited 2021 Mar 08]. Available from: http://dx.doi.org/10.26021/1276.

Council of Science Editors:

Oparah IA. Photosynthetic acclimation to temperature of four Eucalyptus species and Sequoia sempervirens. [Masters Thesis]. University of Canterbury; 2012. Available from: http://dx.doi.org/10.26021/1276

Virginia Tech

29. Snyder, Daniel Joseph. Deactivation Diagram Development for Naval Ship System Vulnerability Analysis.

Degree: MS, Ocean Engineering, 2019, Virginia Tech

URL: http://hdl.handle.net/10919/90220

► As the development of new ships becomes more technically complex due to the increased incorporation of redundant and interdependent ship systems, there is a greater… (more)

Subjects/Keywords: deactivation analysis; vulnerability; ship system design; architecture framework; distributed systems

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Snyder, D. J. (2019). Deactivation Diagram Development for Naval Ship System Vulnerability Analysis. (Masters Thesis). Virginia Tech. Retrieved from http://hdl.handle.net/10919/90220

Chicago Manual of Style (16^th Edition):

Snyder, Daniel Joseph. “Deactivation Diagram Development for Naval Ship System Vulnerability Analysis.” 2019. Masters Thesis, Virginia Tech. Accessed March 08, 2021. http://hdl.handle.net/10919/90220.

MLA Handbook (7^th Edition):

Snyder, Daniel Joseph. “Deactivation Diagram Development for Naval Ship System Vulnerability Analysis.” 2019. Web. 08 Mar 2021.

Vancouver:

Snyder DJ. Deactivation Diagram Development for Naval Ship System Vulnerability Analysis. [Internet] [Masters thesis]. Virginia Tech; 2019. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10919/90220.

Council of Science Editors:

Snyder DJ. Deactivation Diagram Development for Naval Ship System Vulnerability Analysis. [Masters Thesis]. Virginia Tech; 2019. Available from: http://hdl.handle.net/10919/90220

30. Alsulaiman, Yousif Abdulltaif. Effects of injection pressure, post injection, cylinder deactivation and intake throttling on fuel consumption and emissions for a light duty diesel engine at idle condition.

Degree: MSin Engineering, Mechanical Engineering, 2019, University of Texas – Austin

URL: http://dx.doi.org/10.26153/tsw/3434

► Due to their high efficiency and power, the transportation sector relies heavily on diesel engines. However, diesel engines face many challenges regarding their hazardous emissions… (more)

▼ Due to their high efficiency and power, the transportation sector relies heavily on diesel engines. However, diesel engines face many challenges regarding their hazardous emissions and the different regulations for fuel economy which get more stringent over time. One of the main concerns is engine idling where the engine is consuming fuel and emitting pollutants without any utilized power output. In this study, the effects of cylinder deactivation accompanied by throttling and post injection on fuel consumption and emissions were investigated for a 4 cylinder diesel engine at idle conditions. Three different engine operating methods were used. In the 1st method, the engine operated on 4 cylinders, while in the 2nd method; fueling was deactivated for 2 cylinders without valve deactivation. In the last operating method, full cylinder valve deactivation was applied to 2 cylinders. Furthermore, the effects of rail pressure on emissions, IMEP and fuel consumption were investigated. Method 2 with deactivated fueling achieved a minor fuel savings compared to the 4 cylinders operation, between 4-16% depending on the throttling level where more fuel savings were accomplished at higher throttle positions. Method 3 with full cylinder deactivation resulted in 33% fuel savings at WOT compared to Method 1 and 40% at the heaviest throttling level. Pumping losses and fuel consumption were found to increase with throttling, while the net IMEP decreased with heavier throttle conditions. Both CO₂ and hydrocarbons increased with throttling, while NO [subscript x] emissions increased with throttling until 65 kPa of manifold absolute pressure and then started to fall at lower MAP values. These trends correlated with the heat release rate results. Also, fuel consumption and net IMEP increased with a decrease in rail pressure, where the peak heat release rate was more retarded for the lower injection pressure. Finally, the effects of different operating methods and intake throttling on exhaust temperature was analyzed. The temperatures were measured at the exhaust port exits, and for Method 2 prior to any mixing with air from the non-fired cylinders. At wide open throttle (WOT), Method 3 achieved a 20°C increase in exhaust temperature compared to Method 1, and Method 2 resulted in an additional increase of 25°C. Exhaust temperature increased with throttling for all methods, where it rose by 80°C with maximum throttling in Method 1 and 95°C for Methods 2 and 3. Advisors/Committee Members: Hall, M. J. (Matthew John) (advisor), Matthews, Ronald D. (advisor).

Subjects/Keywords: Diesel engine; Cylinder deactivation

…5 Table 2. 2 Injection parameters for the fuel deactivation method (2nd method)… …deactivation (CDA) on fuel consumption and emissions. For each method the fuel consumption… …reduce idling’s negative impacts including cylinder deactivation which is one of the promising… …and to exceed 143 g/mi by 2025 [15]. 1.4 CYLINDER DEACTIVATION Cylinder… …deactivation technology has been of interest recently for cars manufacturers due to its usefulness in…

8 more images…

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APA (6^th Edition):

Alsulaiman, Y. A. (2019). Effects of injection pressure, post injection, cylinder deactivation and intake throttling on fuel consumption and emissions for a light duty diesel engine at idle condition. (Masters Thesis). University of Texas – Austin. Retrieved from http://dx.doi.org/10.26153/tsw/3434

Chicago Manual of Style (16^th Edition):

Alsulaiman, Yousif Abdulltaif. “Effects of injection pressure, post injection, cylinder deactivation and intake throttling on fuel consumption and emissions for a light duty diesel engine at idle condition.” 2019. Masters Thesis, University of Texas – Austin. Accessed March 08, 2021. http://dx.doi.org/10.26153/tsw/3434.

MLA Handbook (7^th Edition):

Alsulaiman, Yousif Abdulltaif. “Effects of injection pressure, post injection, cylinder deactivation and intake throttling on fuel consumption and emissions for a light duty diesel engine at idle condition.” 2019. Web. 08 Mar 2021.

Vancouver:

Alsulaiman YA. Effects of injection pressure, post injection, cylinder deactivation and intake throttling on fuel consumption and emissions for a light duty diesel engine at idle condition. [Internet] [Masters thesis]. University of Texas – Austin; 2019. [cited 2021 Mar 08]. Available from: http://dx.doi.org/10.26153/tsw/3434.

Council of Science Editors:

Alsulaiman YA. Effects of injection pressure, post injection, cylinder deactivation and intake throttling on fuel consumption and emissions for a light duty diesel engine at idle condition. [Masters Thesis]. University of Texas – Austin; 2019. Available from: http://dx.doi.org/10.26153/tsw/3434

Open Access Theses and Dissertations