subject:(neutron)

Oregon State University

1. Boulton, Nicholas M. Commissioning of the NDDL-40 Neutron Detection System at Oregon State University.

Degree: MS, Radiation Health Physics, 2017, Oregon State University

URL: http://hdl.handle.net/1957/60583

► The Neutron radiography facility (NRF) at Oregon State University (OSU) has been modified to begin working on the non-destructive evaluation of concrete materials to study… (more)

Subjects/Keywords: neutron; Neutron radiography – Oregon – Corvallis

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APA (6^th Edition):

Boulton, N. M. (2017). Commissioning of the NDDL-40 Neutron Detection System at Oregon State University. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/60583

Chicago Manual of Style (16^th Edition):

Boulton, Nicholas M. “Commissioning of the NDDL-40 Neutron Detection System at Oregon State University.” 2017. Masters Thesis, Oregon State University. Accessed June 07, 2020. http://hdl.handle.net/1957/60583.

MLA Handbook (7^th Edition):

Boulton, Nicholas M. “Commissioning of the NDDL-40 Neutron Detection System at Oregon State University.” 2017. Web. 07 Jun 2020.

Vancouver:

Boulton NM. Commissioning of the NDDL-40 Neutron Detection System at Oregon State University. [Internet] [Masters thesis]. Oregon State University; 2017. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/1957/60583.

Council of Science Editors:

Boulton NM. Commissioning of the NDDL-40 Neutron Detection System at Oregon State University. [Masters Thesis]. Oregon State University; 2017. Available from: http://hdl.handle.net/1957/60583

2. Wang, Xi. 3D Neutron Diffraction Studies on the Vortex Lattice.

Degree: PhD, Physics, 2012, Brown University

URL: https://repository.library.brown.edu/studio/item/bdr:297705/

► In condensed matter physics the vortex lattice of type-II superconductors provides a prototype for studying the effect of random pinning on elastic systems. One important… (more)

▼ In condensed matter physics the vortex lattice of type-II superconductors provides a prototype for studying the effect of random pinning on elastic systems. One important problem is to understand the structural transition from a theoretically predicted ordered Bragg glass phase to a disordered vortex liquid phase. Defects, such as screw dislocations, should play an important role in mediating this order-disorder transition. It is important to confirm the existence of these defect structures in the vortex lattice. Experimentally it is difficult to probe the detailed defect structures inside the vortex lattice. Traditional methods can only provide information on the surface configuration or an averaged picture of the bulk behavior of the vortex lattice. Here we use a novel high-resolution neutron diffraction technique to probe the angular orientation of the lattice planes as the flux lines traverse the atomic crystal. Our results provide structural evidence for screw dislocations inside the vortex lattice. The anisotropic defect structure in the underlying atomic lattice serves as a symmetry breaking field for the vortex lattice. The strong dependence of the vortex lattice structure on the growth procedure reveals that the system is metastable and can be perturbed through thermal cycling to a possible ground state. We measure the structure of the vortex lattice under different applied magnetic fields and temperatures to study the interplay between vortex-vortex interaction, vortex-atomic lattice interaction, and thermal fluctuations. This high-resolution neutron diffraction technique opens up a new way in studying the detailed structure of the vortex lattice. Our results suggest that the vortex lattice in low temperature superconductors with anisotropic defects in the atomic lattice could be an excellent candidate for exploring the entangled flux liquid phase. Advisors/Committee Members: Ling, Xinsheng (Director), Kosterlitz, J. (Reader), Mitrovic, Vesna (Reader).

Subjects/Keywords: neutron diffraction

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APA (6^th Edition):

Wang, X. (2012). 3D Neutron Diffraction Studies on the Vortex Lattice. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:297705/

Chicago Manual of Style (16^th Edition):

Wang, Xi. “3D Neutron Diffraction Studies on the Vortex Lattice.” 2012. Doctoral Dissertation, Brown University. Accessed June 07, 2020. https://repository.library.brown.edu/studio/item/bdr:297705/.

MLA Handbook (7^th Edition):

Wang, Xi. “3D Neutron Diffraction Studies on the Vortex Lattice.” 2012. Web. 07 Jun 2020.

Vancouver:

Wang X. 3D Neutron Diffraction Studies on the Vortex Lattice. [Internet] [Doctoral dissertation]. Brown University; 2012. [cited 2020 Jun 07]. Available from: https://repository.library.brown.edu/studio/item/bdr:297705/.

Council of Science Editors:

Wang X. 3D Neutron Diffraction Studies on the Vortex Lattice. [Doctoral Dissertation]. Brown University; 2012. Available from: https://repository.library.brown.edu/studio/item/bdr:297705/

Addis Ababa University

3. Atakalti Belay, Belay. TEMPERATURE DEPENDENCE VISCOSITY OF THE NEUTRON STAR MATTER .

Degree: 2012, Addis Ababa University

URL: http://etd.aau.edu.et/dspace/handle/123456789/1422

► In this work, we review the basics of both ideal and non ideal uid dynamics. Funda- mental principles of uid dynamics,solution of nonlinear Boltzmann equation,… (more)

Subjects/Keywords: VISCOSITY; NEUTRON

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APA (6^th Edition):

Atakalti Belay, B. (2012). TEMPERATURE DEPENDENCE VISCOSITY OF THE NEUTRON STAR MATTER . (Thesis). Addis Ababa University. Retrieved from http://etd.aau.edu.et/dspace/handle/123456789/1422

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):

Atakalti Belay, Belay. “TEMPERATURE DEPENDENCE VISCOSITY OF THE NEUTRON STAR MATTER .” 2012. Thesis, Addis Ababa University. Accessed June 07, 2020. http://etd.aau.edu.et/dspace/handle/123456789/1422.

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

MLA Handbook (7^th Edition):

Atakalti Belay, Belay. “TEMPERATURE DEPENDENCE VISCOSITY OF THE NEUTRON STAR MATTER .” 2012. Web. 07 Jun 2020.

Vancouver:

Atakalti Belay B. TEMPERATURE DEPENDENCE VISCOSITY OF THE NEUTRON STAR MATTER . [Internet] [Thesis]. Addis Ababa University; 2012. [cited 2020 Jun 07]. Available from: http://etd.aau.edu.et/dspace/handle/123456789/1422.

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

Council of Science Editors:

Atakalti Belay B. TEMPERATURE DEPENDENCE VISCOSITY OF THE NEUTRON STAR MATTER . [Thesis]. Addis Ababa University; 2012. Available from: http://etd.aau.edu.et/dspace/handle/123456789/1422

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

Tulane University

4. Haun, Robert. Precision measurement of the coherent scattering length of gaseous helium-four using neutron interferometry.

Degree: 2019, Tulane University

URL: https://digitallibrary.tulane.edu/islandora/object/tulane:94534

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[email protected]

This dissertation details a measurement of the n-⁴He coherent scattering length to be b_4{He} = [3.0982 ±\: 0.00214; ({stat}) ±\: 0.00077; ({sys})] fm utilizing… (more)

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[email protected]

This dissertation details a measurement of the n-⁴He coherent scattering length to be b_4{He} = [3.0982 ±\: 0.00214; ({stat}) ±\: 0.00077; ({sys})] fm utilizing a perfect silicon crystal neutron interferometer. This measurement provides over a factor of 10 improvement in precision and differs by 0.162 fm compared to the most commonly used value. Neutron interferometry provides a tool for precision scattering lengths measurements for a variety of isotopes. Examples include coherent scattering length measurements for ¹H, ²H, ³He and the incoherent scattering length of ³He. Neutron scattering lengths of light nuclei provide useful tests of nuclear potential models and serve as inputs for nuclear effective field theories. A monolithic, perfect silicon neutron interferometer splits the wave function of a single neutron via Bragg diffraction into two coherent paths spatially separated to the extent of a few centimeters. A sample of ⁴He gas, contained within an aluminum cell, is introduced into one beam path which produces a phase shift directly proportional to b_4{He}. Significant effort has been spent quantifying important systematic considerations that include thermal transfer from the gas cell to the interferometer crystal and deformation of the gas cell walls due to gas pressure which ranges from 7 bar to 13 bar which were calculated by an FEA simulation. Thermal transfer between the gas cell and interferometer crystal induces a change of the intrinsic interferometer phase which is dependent on sample position. This additional systematic phase has been named the shadow phase. A glycol cooling system was used to mitigate the shadow phase and a special measurement pattern was devised to account for possible shadow phase drift. This work was performed at the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR).

1

Robert Haun

Advisors/Committee Members: Wietfeldt, Fred (Thesis advisor), School of Science & Engineering Physics and Engineering Physics (Degree granting institution).

Subjects/Keywords: Neutron Optics

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APA (6^th Edition):

Haun, R. (2019). Precision measurement of the coherent scattering length of gaseous helium-four using neutron interferometry. (Thesis). Tulane University. Retrieved from https://digitallibrary.tulane.edu/islandora/object/tulane:94534

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):

Haun, Robert. “Precision measurement of the coherent scattering length of gaseous helium-four using neutron interferometry.” 2019. Thesis, Tulane University. Accessed June 07, 2020. https://digitallibrary.tulane.edu/islandora/object/tulane:94534.

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

MLA Handbook (7^th Edition):

Haun, Robert. “Precision measurement of the coherent scattering length of gaseous helium-four using neutron interferometry.” 2019. Web. 07 Jun 2020.

Vancouver:

Haun R. Precision measurement of the coherent scattering length of gaseous helium-four using neutron interferometry. [Internet] [Thesis]. Tulane University; 2019. [cited 2020 Jun 07]. Available from: https://digitallibrary.tulane.edu/islandora/object/tulane:94534.

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

Council of Science Editors:

Haun R. Precision measurement of the coherent scattering length of gaseous helium-four using neutron interferometry. [Thesis]. Tulane University; 2019. Available from: https://digitallibrary.tulane.edu/islandora/object/tulane:94534

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

Georgia Tech

5. Hon, Ryan Paul. Development of methods and tools for on-the-fly response function generation for criticality calculations.

Degree: PhD, Mechanical Engineering, 2016, Georgia Tech

URL: http://hdl.handle.net/1853/58184

► Stochastic Particle Response Calculator, SPaRC, is a new stochastic neutron transport code that has been developed and optimized for the computation of response functions for… (more)

▼ Stochastic Particle Response Calculator, SPaRC, is a new stochastic neutron transport code that has been developed and optimized for the computation of response functions for use in response matrix based whole-core transport solvers. SPaRC transports neutrons from a specified fixed source distribution and computes responses as neutrons stream through and then exit regions of interest. The code makes use of both multi-group and continuous energy nuclear data and takes advantage of parallel computing through the message passing interface (MPI). In order to test the neutron transport routine, various small benchmark problems were solved with SPaRC and compared to results generated with MCNP. Results show excellent agreement between the solutions generated by these codes for both multi-group and continuous energy calculations. The responses generated by SPaRC have been tailored for use in the coarse mesh transport (COMET) method. COMET is a hybrid stochastic/deterministic method shown to compute fast and accurate solutions for a variety of nuclear systems. In order to obtain these solutions, COMET makes use of pre-computed response functions aggregated into a library for use in a deterministic iteration scheme. Previously these response functions were calculated with MCNP and took place before a transport calculation. SPaRC also generates these response functions for use with the COMET method, with the added capability of performing these calculations during the transport routine as needed. This on-the-fly capability for response generation enables the use of the COMET method for calculations where the state of a problem changes with time. SPaRC’s ability to generate responses during a calculation eliminates the need for a fully pre-computed response library to cover the entire possible solution space, extending the capability of COMET to neutronics problems involving multi-physics feedback, such as thermal-hydraulic and depletion calculations. Sample calculations on the reactor assembly level were performed in order to test the accuracy of the SPaRC generated response functions. First, responses were generated for uncontrolled, controlled, and gadded assemblies with both MCNP and SPaRC. Next, COMET calculations were performed using these two sets of responses for the different assembly types in order to generate eigenvalues and pin fission density distributions. The results generated from the MCNP and SPaRC responses agreed within 0.05% for the core eigenvalue and within 0.002% for pin powers. SPaRC is a newly developed fixed-source radiation transport code. The neutron transport method has been benchmarked against the stochastic transport code MCNP with good agreement and new database management and creation routines have been developed to aid response generation. SPaRC introduces a response function flexibility to the COMET method that facilitates thermal hydraulic and depletion calculations. Advisors/Committee Members: Rahnema, Farzad (advisor), Petrovic, Bojan (committee member), Zhang, Dingkang (committee member), Chow, Edmond (committee member), Haghighat, Alireza (committee member), Leal, Luiz (committee member).

Subjects/Keywords: Neutron transport

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APA (6^th Edition):

Hon, R. P. (2016). Development of methods and tools for on-the-fly response function generation for criticality calculations. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/58184

Chicago Manual of Style (16^th Edition):

Hon, Ryan Paul. “Development of methods and tools for on-the-fly response function generation for criticality calculations.” 2016. Doctoral Dissertation, Georgia Tech. Accessed June 07, 2020. http://hdl.handle.net/1853/58184.

MLA Handbook (7^th Edition):

Hon, Ryan Paul. “Development of methods and tools for on-the-fly response function generation for criticality calculations.” 2016. Web. 07 Jun 2020.

Vancouver:

Hon RP. Development of methods and tools for on-the-fly response function generation for criticality calculations. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/1853/58184.

Council of Science Editors:

Hon RP. Development of methods and tools for on-the-fly response function generation for criticality calculations. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/58184

University of New South Wales

6. White, Reyner. Magnetism and Properties of Three Rare Earth Intermetallic Series.

Degree: Physical, Environmental & Mathematical Sciences, 2018, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/59807 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:49839/SOURCE02?view=true

► Three intermetallic series with increasing rare earth dilution are examined and their magnetic and physical properties are determined. Of the first series, RNiAl₄, five materials… (more)

▼ Three intermetallic series with increasing rare earth dilution are examined and their magnetic and physical properties are determined. Of the first series, RNiAl₄, five materials are examined. For the TbNiAl₄ case, the incommensurate magnetic structure has been determined and then used to rationalise results from previous low temperature nuclear orientation (LTNO) studies. Similarly for NdNiAl₄, a model incommensurate structure has been used to simulate an LTNO experiment. For PrNiAl₄, the presence of an incommensurate magnetic phase has been confirmed and the magnetic structure determined. For ErNiAl₄, the magnetic structure has been charted from well below the ordering temperature to well above it. In DyNiAl₄, two magnetic structures have been identified: a higher temperature incommensurate phase and a lower temperature commensurate phase and these coexist in zero applied field, a first for the series. A reanalysis of existing TbNiAl₄ data has also identified similar phase coexistence. The collective results are used to examine trends across the series.Of the RM₂Al₁₀ series, TbRu₂Al₁₀ has been examined in depth. The material possesses two phase transitions as a function of temperature at TN = 15.0(3) K and TN' = 6.5(3) K and three more as a function of applied field at 2 K, at 1.30(3) T, 1.85(3) T and 3.20(3) T. These metamagnetic transitions transform the low temperature incommensurate square wave structure into two identifiably different 'pulse wave' structures and then to a para/ferromagnetic structure respectively. A magnetic phase diagram has been created and comparisons between TbRu₂Al₁₀ and other RM₂Al₁₀ compounds have been made as well as comparisons with the RNiAl₄ series.For the RM₂Al₂₀ series, three materials were analysed. For NdTi₂Al₂₀, a neutron diffraction experiment was performed at very low temperatures (70 mK) however no magnetic diffraction peaks were observed. DyTi₂Al₂₀ was subject to a similar experiment at 30 mK, where a commensurate antiferromagnetic structure was found. For TmV₂Al₂₀, inelastic neutron scattering was used to determine the crystal field parameters of the Tm³⁺ ion. Improvements were made to the original parameters obtained from bulk measurements, with W = 0.43(1) K and x = -0.63(1) using the Lea, Leask and Wolf formalism. Advisors/Committee Members: Hutchison, Wayne, Physical, Environmental & Mathematical Sciences, UNSW Canberra, UNSW, Cadogan, Sean, Physical, Environmental & Mathematical Sciences, UNSW Canberra, UNSW.

Subjects/Keywords: Neutron Diffraction; Magnetism; Intermetallics; Inelastic Neutron Scattering

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APA (6^th Edition):

White, R. (2018). Magnetism and Properties of Three Rare Earth Intermetallic Series. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/59807 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:49839/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

White, Reyner. “Magnetism and Properties of Three Rare Earth Intermetallic Series.” 2018. Doctoral Dissertation, University of New South Wales. Accessed June 07, 2020. http://handle.unsw.edu.au/1959.4/59807 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:49839/SOURCE02?view=true.

MLA Handbook (7^th Edition):

White, Reyner. “Magnetism and Properties of Three Rare Earth Intermetallic Series.” 2018. Web. 07 Jun 2020.

Vancouver:

White R. Magnetism and Properties of Three Rare Earth Intermetallic Series. [Internet] [Doctoral dissertation]. University of New South Wales; 2018. [cited 2020 Jun 07]. Available from: http://handle.unsw.edu.au/1959.4/59807 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:49839/SOURCE02?view=true.

Council of Science Editors:

White R. Magnetism and Properties of Three Rare Earth Intermetallic Series. [Doctoral Dissertation]. University of New South Wales; 2018. Available from: http://handle.unsw.edu.au/1959.4/59807 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:49839/SOURCE02?view=true

Kansas State University

7. Cooper, Brian. Microstructured silicon carbide neutron detectors.

Degree: MS, Department of Mechanical and Nuclear Engineering, 2019, Kansas State University

URL: http://hdl.handle.net/2097/40097

► Silicon carbide is a material of interest in many ventures as an intriguing semiconducting material for use as high voltage, high temperature, high power, or… (more)

▼ Silicon carbide is a material of interest in many ventures as an intriguing semiconducting material for use as high voltage, high temperature, high power, or high frequency devices. Silicon carbide is physically extremely tough and durable and is also very chemically resistant. The work presented here details using silicon carbide (SiC) as the semiconducting substrate for a high-efficiency neutron detector. The work begins with the fabrication of planar SiC neutron detectors utilizing 10B as the neutron conversion material. The SiC substrate was patterned via photolithography techniques prior to the deposition of an etchant mask. The following materials were used as etchant mask materials; nickel, indium tin oxide, and aluminum. The SiC devices were plasma etched using SF6 based gas chemistries. The desired trench profile was 4 microns wide with desired depth between 10 and 20 microns. The formation of microfeatures within the trenches was observed during several etching trials as well as the trench profile narrowing to a point. After etching, titanium/gold contacts were fabricated using e-beam evaporation and various masking techniques. Next the devices were electrically tested for leakage current and capacitance. Typical leakage current was <10 pA at 100 V applied bias with a capacitance of <10 pF. Then the devices were backfilled with enriched 10B powder. The backfilled devices were tested with alpha particles, gamma rays, and neutrons. The neutron sources used were 252Cf and the Kansas State University TRIGA Reactor diffracted beamport. The devices proved to have low gamma sensitivity with respect to neutrons. When the devices were irradiated by high-activity alpha particle sources, significant charge trapping and device polarization was observed. The initial devices were 10 mm x 10 mm, but due to complications during the etchant mask formation, the device size was changed to 5 mm x 5 mm. The 5 mm x 5 mm devices were tested for neutron sensitivity using the 252Cf source and the diffracted beamport. Thermal neutron efficiency of 2.28±0.031% was measured. The final SiC wafer was patterned with the top contact and etchant mask. However, during dicing, the layers delaminated and peeled of the SiC substrate. Substantial efforts were made to pattern the remaining partial wafer to little success. Advisors/Committee Members: Douglas S. McGregor.

Subjects/Keywords: Silicon carbide; Neutron; Neutron detector; Plasma etching

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APA (6^th Edition):

Cooper, B. (2019). Microstructured silicon carbide neutron detectors. (Masters Thesis). Kansas State University. Retrieved from http://hdl.handle.net/2097/40097

Chicago Manual of Style (16^th Edition):

Cooper, Brian. “Microstructured silicon carbide neutron detectors.” 2019. Masters Thesis, Kansas State University. Accessed June 07, 2020. http://hdl.handle.net/2097/40097.

MLA Handbook (7^th Edition):

Cooper, Brian. “Microstructured silicon carbide neutron detectors.” 2019. Web. 07 Jun 2020.

Vancouver:

Cooper B. Microstructured silicon carbide neutron detectors. [Internet] [Masters thesis]. Kansas State University; 2019. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/2097/40097.

Council of Science Editors:

Cooper B. Microstructured silicon carbide neutron detectors. [Masters Thesis]. Kansas State University; 2019. Available from: http://hdl.handle.net/2097/40097

University of Tennessee – Knoxville

8. Rinehart, Samantha Jae. Neutron Studies of Multi-Component Polymer Thin Films: Stratification and Interfacial Structure.

Degree: 2019, University of Tennessee – Knoxville

URL: https://trace.tennessee.edu/utk_graddiss/5430

► This dissertation presents the impact fabrication conditions have upon layer composition, purity, and interfacial clarity of multi-component thin films on both rigid and flexible substrates.… (more)

▼ This dissertation presents the impact fabrication conditions have upon layer composition, purity, and interfacial clarity of multi-component thin films on both rigid and flexible substrates. The performance of the multi-functional thin films is directly linked to the macroscopic assembly in a thin film. Prior to production of a novel thin film systems, the suitable fabrication methods required for optimum performance must be determined. Oftentimes, this is pursued on a tedious trial and error basis. Thus, guidelines established upon the thermodynamic and kinetic properties of the thin film are essential for improving processing efficiency and enhancing overall product performance.Chapter Two of this dissertation outlines the procedure for a novel method of quantifying the stratification of polymer blend thin films. Application of this technique revealed definitive control over the final film depth profile simply by altering the processing conditions. Instead of simply stating the effect of processing condition upon the final film depth profile and the extent of stratification, each processing condition was reported as the thermodynamic and kinetic properties of fabrication. Chapter Three expands upon the thermodynamic driving forces responsible for stratification outlined in Chapter Two and describes a hierarchy of thermodynamic properties responsible for stratification. Both Chapter Two and Three investigate the vertical stratification of a polymer blend. Chapter Four considers the lateral phase separation of the blend under the same thermodynamic and kinetic parameters. Chapter Five investigates the extent of control substrate rigidity has upon the order of the thin film and the order at each interface of sputtered multi-layer thin films.Ultimately, this work provides strong evidence that each processing parameter influences the entire structure of thin films. Control of polymer processing (either as a blend or as substrates) is crucial for product and thin film fabrication. The lack of control during processing will result in inconsistent final film structures, a film feature known to impact product performance. With the knowledge of stratification control and substrate influence upon final film structure, this information can be tailored to a diverse collection of polymer blended systems and endless multi-component applications.

Subjects/Keywords: polymer; neutron scattering; neutron reflectivity; stratification; interfaces

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APA (6^th Edition):

Rinehart, S. J. (2019). Neutron Studies of Multi-Component Polymer Thin Films: Stratification and Interfacial Structure. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/5430

Chicago Manual of Style (16^th Edition):

Rinehart, Samantha Jae. “Neutron Studies of Multi-Component Polymer Thin Films: Stratification and Interfacial Structure.” 2019. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed June 07, 2020. https://trace.tennessee.edu/utk_graddiss/5430.

MLA Handbook (7^th Edition):

Rinehart, Samantha Jae. “Neutron Studies of Multi-Component Polymer Thin Films: Stratification and Interfacial Structure.” 2019. Web. 07 Jun 2020.

Vancouver:

Rinehart SJ. Neutron Studies of Multi-Component Polymer Thin Films: Stratification and Interfacial Structure. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2019. [cited 2020 Jun 07]. Available from: https://trace.tennessee.edu/utk_graddiss/5430.

Council of Science Editors:

Rinehart SJ. Neutron Studies of Multi-Component Polymer Thin Films: Stratification and Interfacial Structure. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2019. Available from: https://trace.tennessee.edu/utk_graddiss/5430

University of Utah

9. Moffitt, Gregory Bruce. Neutron interaction tool, pyNIC for advanced applications in nuclear power, nuclear medicine, and nuclear security.

Degree: MS, Civil & Environmental Engineering, 2014, University of Utah

URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3338/rec/1681

► A neutron interaction simulation tool, PyNIC, was developed for the calculation of neutron activation products and prompt gamma ray emission from neutron capture, neutron inelastic… (more)

Subjects/Keywords: Activation; Analysis; Neutron

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APA (6^th Edition):

Moffitt, G. B. (2014). Neutron interaction tool, pyNIC for advanced applications in nuclear power, nuclear medicine, and nuclear security. (Masters Thesis). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3338/rec/1681

Chicago Manual of Style (16^th Edition):

Moffitt, Gregory Bruce. “Neutron interaction tool, pyNIC for advanced applications in nuclear power, nuclear medicine, and nuclear security.” 2014. Masters Thesis, University of Utah. Accessed June 07, 2020. http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3338/rec/1681.

MLA Handbook (7^th Edition):

Moffitt, Gregory Bruce. “Neutron interaction tool, pyNIC for advanced applications in nuclear power, nuclear medicine, and nuclear security.” 2014. Web. 07 Jun 2020.

Vancouver:

Moffitt GB. Neutron interaction tool, pyNIC for advanced applications in nuclear power, nuclear medicine, and nuclear security. [Internet] [Masters thesis]. University of Utah; 2014. [cited 2020 Jun 07]. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3338/rec/1681.

Council of Science Editors:

Moffitt GB. Neutron interaction tool, pyNIC for advanced applications in nuclear power, nuclear medicine, and nuclear security. [Masters Thesis]. University of Utah; 2014. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3338/rec/1681

Johannes Gutenberg Universität Mainz

10. Siemensen, Christian. Untersuchung der Ladung des Neutrons.

Degree: 2015, Johannes Gutenberg Universität Mainz

URL: http://ubm.opus.hbz-nrw.de/volltexte/2015/4170/

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Die Quantisierung der elektrischen Ladung ist eine der größten Fragestellungen der Physik, die bis heute nicht verstanden ist. Im Standardmodell der Teilchenphysik ist sie beispielsweise… (more)

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Die Quantisierung der elektrischen Ladung ist eine der größten Fragestellungen der Physik, die bis heute nicht verstanden ist. Im Standardmodell der Teilchenphysik ist sie beispielsweise nicht mathematisch inhärent erklärbar. Dadurch wäre es möglich, dass das Neutron eine winzige Ladung tragen kann. In dieser Arbeit wurde eine Apparatur auf Grundlage eines Vorgängerexperiments entwickelt, mit der eine Untersuchung der Ladung des Neutrons mit höchster Präzision durchgeführt werden kann. Dabei werden ultrakalte Neutronen in einem optischen System einem elektrischen Feld zwischen zwei Elektrodenplatten ausgesetzt. In der ersten Ladungsmessung mit dieser Apparatur konnte eine statistische Sensitivität von δq≈2,4∙10⁻²⁰ e/√d erreicht werden. Diese Sensitivität ist die höchste, die bisher mit ultrakalten Neutronen für eine Ladungsmessung erreicht werden konnte. In dieser Arbeit wurde das Konzept des Vorgängerexperiments grundlegend überarbeitet, um die Sensitivität der Apparatur zu erhöhen. Es wurden detaillierte Untersuchungen der Systematik der Apparatur durchgeführt und das theoretische Potential der Sensitivität von derzeit δq≈10⁻²¹ e/√d ermittelt. Mit dieser Apparatur wurde der Grundstein für die Messung einer neuen niedrigeren oberen Grenze der elektrischen Ladung des Neutrons gelegt. In nächster Zeit kann dadurch eine niedrigere obere Grenze für die Ladung des Neutrons von q≈10⁻²² e erzielt werden.

The quantization of the electric charge is one of the biggest mysteries in physics and not understood until now. In the standard model of particle physics, it is however not mathematically inherent explainable. Thus, the neutron can carry a tiny charge. In this thesis an apparatus was designed to test the neutron electric charge with highest precision. It is based on a former experiment. Ultracold neutrons are exposed to an electric field between two electrodes in an optical system. The first charge measurement with this apparatus yielded a statistical sensitivity of δq≈2,4∙10⁻²⁰ e / √d. This sensitivity is the highest that could be achieved so far with ultracold neutrons for a charge measurement. In this work, the concept of the previous experiment was fundamentally revised in order to increase the sensitivity of the apparatus. Detailed studies of the setup revealed its theoretical sensitivity of currently δq≈10⁻²¹ e / √d. This apparatus is the basis for the measurement of a new lower upper limit of the electric charge of the neutron. In the near future, a lower upper limit for the charge of the neutron of q≈10⁻²² e can be achieved.

Subjects/Keywords: Ladungsquantisierung; UCN; Neutronenoptik; Neutron; Neutronenladung; Electric charge quantisation; UCN; neutron optics; neutron; neutron charge; Physics

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APA (6^th Edition):

Siemensen, C. (2015). Untersuchung der Ladung des Neutrons. (Doctoral Dissertation). Johannes Gutenberg Universität Mainz. Retrieved from http://ubm.opus.hbz-nrw.de/volltexte/2015/4170/

Chicago Manual of Style (16^th Edition):

Siemensen, Christian. “Untersuchung der Ladung des Neutrons.” 2015. Doctoral Dissertation, Johannes Gutenberg Universität Mainz. Accessed June 07, 2020. http://ubm.opus.hbz-nrw.de/volltexte/2015/4170/.

MLA Handbook (7^th Edition):

Siemensen, Christian. “Untersuchung der Ladung des Neutrons.” 2015. Web. 07 Jun 2020.

Vancouver:

Siemensen C. Untersuchung der Ladung des Neutrons. [Internet] [Doctoral dissertation]. Johannes Gutenberg Universität Mainz; 2015. [cited 2020 Jun 07]. Available from: http://ubm.opus.hbz-nrw.de/volltexte/2015/4170/.

Council of Science Editors:

Siemensen C. Untersuchung der Ladung des Neutrons. [Doctoral Dissertation]. Johannes Gutenberg Universität Mainz; 2015. Available from: http://ubm.opus.hbz-nrw.de/volltexte/2015/4170/

University of Illinois – Urbana-Champaign

11. Myers, Luke S. Deuteron compton scattering below pion threshold.

Degree: PhD, 0240, 2011, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/18332

► A series of experiments were performed at the Tagged Photon Facility at MAX-lab in Lund, Sweden to study photon scattering from the deuteron and extract… (more)

Subjects/Keywords: Neutron; Isoscalar; Polarizability

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APA (6^th Edition):

Myers, L. S. (2011). Deuteron compton scattering below pion threshold. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/18332

Chicago Manual of Style (16^th Edition):

Myers, Luke S. “Deuteron compton scattering below pion threshold.” 2011. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed June 07, 2020. http://hdl.handle.net/2142/18332.

MLA Handbook (7^th Edition):

Myers, Luke S. “Deuteron compton scattering below pion threshold.” 2011. Web. 07 Jun 2020.

Vancouver:

Myers LS. Deuteron compton scattering below pion threshold. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2011. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/2142/18332.

Council of Science Editors:

Myers LS. Deuteron compton scattering below pion threshold. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2011. Available from: http://hdl.handle.net/2142/18332

Clemson University

12. Huffer, Benjamin David. Porous Nanostructured 4Ï€ Neutron Conversion Layers for Improved Sensitivity and Gamma-Ray Rejection in Gas-Filled Radiation Detectors.

Degree: MS, Environmental Engineering and Earth Sciences, 2019, Clemson University

URL: https://tigerprints.clemson.edu/all_theses/3153

► This work investigated a neutron detection media comprising porous nanomaterial membranes to mitigate self-absorbance of neutron reaction products (Î±, 7Li) typical of micron-sized neutron… (more)

Subjects/Keywords: BNNTs; Neutron Detection

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APA (6^th Edition):

Huffer, B. D. (2019). Porous Nanostructured 4Ï€ Neutron Conversion Layers for Improved Sensitivity and Gamma-Ray Rejection in Gas-Filled Radiation Detectors. (Masters Thesis). Clemson University. Retrieved from https://tigerprints.clemson.edu/all_theses/3153

Chicago Manual of Style (16^th Edition):

Huffer, Benjamin David. “Porous Nanostructured 4Ï€ Neutron Conversion Layers for Improved Sensitivity and Gamma-Ray Rejection in Gas-Filled Radiation Detectors.” 2019. Masters Thesis, Clemson University. Accessed June 07, 2020. https://tigerprints.clemson.edu/all_theses/3153.

MLA Handbook (7^th Edition):

Huffer, Benjamin David. “Porous Nanostructured 4Ï€ Neutron Conversion Layers for Improved Sensitivity and Gamma-Ray Rejection in Gas-Filled Radiation Detectors.” 2019. Web. 07 Jun 2020.

Vancouver:

Huffer BD. Porous Nanostructured 4Ï€ Neutron Conversion Layers for Improved Sensitivity and Gamma-Ray Rejection in Gas-Filled Radiation Detectors. [Internet] [Masters thesis]. Clemson University; 2019. [cited 2020 Jun 07]. Available from: https://tigerprints.clemson.edu/all_theses/3153.

Council of Science Editors:

Huffer BD. Porous Nanostructured 4Ï€ Neutron Conversion Layers for Improved Sensitivity and Gamma-Ray Rejection in Gas-Filled Radiation Detectors. [Masters Thesis]. Clemson University; 2019. Available from: https://tigerprints.clemson.edu/all_theses/3153

Colorado School of Mines

13. Wilson, Clinton R. Beamline improvements to the MInes NEutron Radiography (MINER) facility.

Degree: MS(M.S.), Metallurgical and Materials Engineering, 2017, Colorado School of Mines

URL: http://hdl.handle.net/11124/170599

► The Colorado School of Mines designed and installed a neutron radiography system at the United States Geological Survey TRIGA reactor (GSTR) in 2012. Several potential… (more)

Subjects/Keywords: Neutron; Beamline; Radiography

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APA (6^th Edition):

Wilson, C. R. (2017). Beamline improvements to the MInes NEutron Radiography (MINER) facility. (Masters Thesis). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/170599

Chicago Manual of Style (16^th Edition):

Wilson, Clinton R. “Beamline improvements to the MInes NEutron Radiography (MINER) facility.” 2017. Masters Thesis, Colorado School of Mines. Accessed June 07, 2020. http://hdl.handle.net/11124/170599.

MLA Handbook (7^th Edition):

Wilson, Clinton R. “Beamline improvements to the MInes NEutron Radiography (MINER) facility.” 2017. Web. 07 Jun 2020.

Vancouver:

Wilson CR. Beamline improvements to the MInes NEutron Radiography (MINER) facility. [Internet] [Masters thesis]. Colorado School of Mines; 2017. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/11124/170599.

Council of Science Editors:

Wilson CR. Beamline improvements to the MInes NEutron Radiography (MINER) facility. [Masters Thesis]. Colorado School of Mines; 2017. Available from: http://hdl.handle.net/11124/170599

Georgia Tech

14. Sharma, Ketki. Electrosorption of ions from aqueous solutions by mesoporous carbon materials.

Degree: PhD, Civil and Environmental Engineering, 2014, Georgia Tech

URL: http://hdl.handle.net/1853/53399

► Electrosorption involves the application of an electrical potential between carbon electrode pairs submerged in brackish water, effectively “trapping” the ions in an electrical double layer… (more)

▼ Electrosorption involves the application of an electrical potential between carbon electrode pairs submerged in brackish water, effectively “trapping” the ions in an electrical double layer at the solid-liquid interface. Electrosorption has significant applications in environmental engineering, including desalination of water by capacitive deionization (CDI), and in energy storage by supercapacitors. This work combines experimental and modeling studies to investigate the transport and sorption mechanisms of ions in the pores of mesoporous carbon materials that were synthesized at the Oak Ridge National Laboratory (ORNL). The main contribution of this research is examining the effects of operational parameters such as applied potential, solution temperature, ionic concentration, and valence of ions, on the electrosorption behavior of mesoporous carbon materials with the aim to improve the desalination efficiency in the CDI process. It was found that the rates of sorption by mesoporous carbon electrodes and their regeneration increased at a higher temperature and on application of a high-frequency, low-amplitude AC signal. Neutron imaging has been employed as a tool to visually observe and quantify the transport and distribution of ions within the carbon electrodes. The neutron images revealed interesting ion transport phenomena that can aid in the optimization of the CDI process. From the ion concentration profiles inside the electrodes, the effective diffusivities of gadolinium and lithium ions were obtained under various conditions of applied potential. Information on the diffusivity of ions can aid in theoretical modeling of the CDI process as well as guide strategies for the design of advanced electrode materials. In the final part of the study, the extraction of salinity gradient energy or ‘blue energy’ by mixing fluids of different salinities was assessed based on the principle of capacitive double layer expansion. Neutron imaging of blue energy recovery cycles was conducted to observe the ion transport behavior during the various steps of the cycle. The results obtained provide insights into the fundamental ion transport mechanisms during electrosorption by mesoporous carbon materials. This research has important implications for developing advanced system designs for desalination of saline water and energy storage devices. Advisors/Committee Members: Yiacoumi, Sotira (advisor), Tsouris, Costas (committee member), Pavlostathis, Spyros G. (committee member), Payne, Christine (committee member), Huang, Ching-Hua (committee member).

Subjects/Keywords: Electrosorption; Neutron imaging

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APA (6^th Edition):

Sharma, K. (2014). Electrosorption of ions from aqueous solutions by mesoporous carbon materials. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/53399

Chicago Manual of Style (16^th Edition):

Sharma, Ketki. “Electrosorption of ions from aqueous solutions by mesoporous carbon materials.” 2014. Doctoral Dissertation, Georgia Tech. Accessed June 07, 2020. http://hdl.handle.net/1853/53399.

MLA Handbook (7^th Edition):

Sharma, Ketki. “Electrosorption of ions from aqueous solutions by mesoporous carbon materials.” 2014. Web. 07 Jun 2020.

Vancouver:

Sharma K. Electrosorption of ions from aqueous solutions by mesoporous carbon materials. [Internet] [Doctoral dissertation]. Georgia Tech; 2014. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/1853/53399.

Council of Science Editors:

Sharma K. Electrosorption of ions from aqueous solutions by mesoporous carbon materials. [Doctoral Dissertation]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/53399

Georgia Tech

15. Benson, Bixler C. Feasibility of creating a neutron detector array for the detection of special nuclear materials.

Degree: MS, Mechanical Engineering, 2015, Georgia Tech

URL: http://hdl.handle.net/1853/60397

► The purpose of this research is to determine the feasibility of creating an energy-dependent neutron detector array that could be used to detect special nuclear… (more)

▼ The purpose of this research is to determine the feasibility of creating an energy-dependent neutron detector array that could be used to detect special nuclear materials. The proposed detector array is composed of idealized thermal neutron detectors covered by moderators of differing size, namely thickness and shape. Through a series of Monte Carlo radiation transport calculations, the size, shape, and location of the moderators and detectors were configured to determine the efficacy of obtaining a neutron energy spectrum or spectral information in a single measurement. This approach expands on the concepts of the Bonner Sphere Spectrometer (BSS) which relies on multiple measurements using differing size moderating spheres. Although a proven approach, the traditional BSS method is not practicable for military applications. The alternative approach to the spectrum measurement is the use of detector sums or ratios to distinguish fission neutron spectra from other neutron spectra that might be encountered. Several 5x5 detector/moderator arrays were modeled in MCNP to determine which models would have the best responses to monoenergetic neutron sources. Five models of 5x5 detector arrays were chosen that best optimize the detectors reaction rates over certain energy ranges. This 5x25 detector array was then simulated with monoenergetic neutron sources and fission sources. A least squares fitting method was attempted to find coefficients that would generate a weighted sum of detectors that yield a flat fluence response. The response function did not have a flat response. The 5x25 detector system did produce characteristic curves for moderated and unmoderated fission sources. A 5x30 detector array that contained a 5x5 detector array that had a beryllium layer was also simulated. The 5x30 detector array had a higher response to high energy neutrons, but not a significant increase for low energy neutrons. The resulting 5x25 system that was designed is capable of being vehicle mounted so it would be mobile. This research shows that it is feasible to create a neutron detector array that is sensitive to neutron energy spectra. Advisors/Committee Members: Hertel, Nolan (advisor), Wang, Chris (committee member), Shannon, Michael (committee member).

Subjects/Keywords: Neutron detection; MCNP

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APA (6^th Edition):

Benson, B. C. (2015). Feasibility of creating a neutron detector array for the detection of special nuclear materials. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/60397

Chicago Manual of Style (16^th Edition):

Benson, Bixler C. “Feasibility of creating a neutron detector array for the detection of special nuclear materials.” 2015. Masters Thesis, Georgia Tech. Accessed June 07, 2020. http://hdl.handle.net/1853/60397.

MLA Handbook (7^th Edition):

Benson, Bixler C. “Feasibility of creating a neutron detector array for the detection of special nuclear materials.” 2015. Web. 07 Jun 2020.

Vancouver:

Benson BC. Feasibility of creating a neutron detector array for the detection of special nuclear materials. [Internet] [Masters thesis]. Georgia Tech; 2015. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/1853/60397.

Council of Science Editors:

Benson BC. Feasibility of creating a neutron detector array for the detection of special nuclear materials. [Masters Thesis]. Georgia Tech; 2015. Available from: http://hdl.handle.net/1853/60397

University of Florida

16. Harkness, Allen Ira, III. Safeguards Approaches for Spent Nuclear Fuel in Dry Cask Storage.

Degree: PhD, Nuclear Engineering Sciences - Nuclear and Radiological Engineering, 2018, University of Florida

URL: https://ufdc.ufl.edu/UFE0052917

► Spent nuclear fuel is currently being stored in dry casks as an interim storage solution. Demand for this storage method has increased globally and the… (more)

Subjects/Keywords: mcnp – neutron – safeguards

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APA (6^th Edition):

Harkness, Allen Ira, I. (2018). Safeguards Approaches for Spent Nuclear Fuel in Dry Cask Storage. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0052917

Chicago Manual of Style (16^th Edition):

Harkness, Allen Ira, III. “Safeguards Approaches for Spent Nuclear Fuel in Dry Cask Storage.” 2018. Doctoral Dissertation, University of Florida. Accessed June 07, 2020. https://ufdc.ufl.edu/UFE0052917.

MLA Handbook (7^th Edition):

Harkness, Allen Ira, III. “Safeguards Approaches for Spent Nuclear Fuel in Dry Cask Storage.” 2018. Web. 07 Jun 2020.

Vancouver:

Harkness, Allen Ira I. Safeguards Approaches for Spent Nuclear Fuel in Dry Cask Storage. [Internet] [Doctoral dissertation]. University of Florida; 2018. [cited 2020 Jun 07]. Available from: https://ufdc.ufl.edu/UFE0052917.

Council of Science Editors:

Harkness, Allen Ira I. Safeguards Approaches for Spent Nuclear Fuel in Dry Cask Storage. [Doctoral Dissertation]. University of Florida; 2018. Available from: https://ufdc.ufl.edu/UFE0052917

RMIT University

17. Keehan, S. Risks posed by neutron contamination in high energy radiotherapy.

Degree: 2017, RMIT University

URL: http://researchbank.rmit.edu.au/view/rmit:162207

► Radiotherapy is a common cancer treatment which aims to use radiation energy to kill tumour cells without damaging healthy tissue. High energy x-rays penetrate tissue… (more)

▼ Radiotherapy is a common cancer treatment which aims to use radiation energy to kill tumour cells without damaging healthy tissue. High energy x-rays penetrate tissue deeply, depositing most of their energy beyond the skin and shallow tissues. X-rays with energies above 8 MeV may interact to produce neutrons, to which the patient is then exposed. Treatment planning systems (TPS), which calculate the amount of energy deposited to biological structures, do not currently account for contaminant neutrons produced in high energy interactions. Constant improvements in modern radiotherapy techniques have resulted in better patient life expectancy than ever before. The unfortunate corollary of increased life span is increased manifestation of late onset side effects from low dose radiation exposure. This has resulted in an increased drive to reduce the dose to untargeted tissues as much as possible. A perfect treatment plan delivers a prescribed dose to the target volume and no dose to any other tissue. In reality, there is always some tissue through which the radiation must pass in order to reach the target, and some energy which passes beyond the intended target volume. In addition, there is unavoidable scattering of radiation within the patient, which results in out-of-field doses to untargeted tissue. Dose to untargeted tissues resulting from x-ray energy is relatively well understood and is calculated and reported by TPS. Dose resulting from contaminant neutrons is not currently considered by TPS. The overall number of neutrons produced is relatively low, because high energy x-rays may interact in a variety ways and reactions producing neutrons are generally less likely. However, energy deposited by radiation can produce different biological outcomes depending on the type of radiation which deposits the energy. The biological damage inflicted by neutron radiation depends on the energy of the neutrons, and neutrons with energy around 1 MeV may be up to 20 times more damaging than x-rays. So, how do we know the risk associated with neutrons produced from high energy x-rays? Measure the number of neutrons produced? Measure the amount of energy they deposit? Neutron radiation is incredibly difficult to quantify, much more so than alpha, beta, x-ray, gamma or proton radiation. Neutrons are neutrally charged particles, which means they are not attracted or repelled by the positive nuclei or negative electrons which make up all matter. Neutrons primarily pass straight through most materials without leaving a trace of evidence. This makes them quite difficult to detect! Neutrons do interact with the nuclei of some materials, in nuclear reactions, which produce energy and secondary particles which can more easily be detected. The extra energy released in these interactions and their complex probability functions make it difficult to determine the number of neutrons or the energy they would release in human tissue. The high uncertainty in neutron measurement techniques has resulted in some controversy around the use of…

Subjects/Keywords: Fields of Research; Neutron; Radiotherapy; Neutron detection; Neutron dosimetry; Activation

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APA (6^th Edition):

Keehan, S. (2017). Risks posed by neutron contamination in high energy radiotherapy. (Thesis). RMIT University. Retrieved from http://researchbank.rmit.edu.au/view/rmit:162207

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):

Keehan, S. “Risks posed by neutron contamination in high energy radiotherapy.” 2017. Thesis, RMIT University. Accessed June 07, 2020. http://researchbank.rmit.edu.au/view/rmit:162207.

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

MLA Handbook (7^th Edition):

Keehan, S. “Risks posed by neutron contamination in high energy radiotherapy.” 2017. Web. 07 Jun 2020.

Vancouver:

Keehan S. Risks posed by neutron contamination in high energy radiotherapy. [Internet] [Thesis]. RMIT University; 2017. [cited 2020 Jun 07]. Available from: http://researchbank.rmit.edu.au/view/rmit:162207.

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

Council of Science Editors:

Keehan S. Risks posed by neutron contamination in high energy radiotherapy. [Thesis]. RMIT University; 2017. Available from: http://researchbank.rmit.edu.au/view/rmit:162207

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

Stellenbosch University

18. Singo, Thifhelimbilu Daphney. Development of a high flux neutron radiation detection system for in-core temperature monitoring.

Degree: PhD, Physics, 2012, Stellenbosch University

URL: http://hdl.handle.net/10019.1/19999

► ENGLISH ABSTRACT: The objective of this research was to develop a neutron detection system that incorporates a mass spectrometer to measure high neutron flux in… (more)

▼ ENGLISH ABSTRACT: The objective of this research was to develop a neutron detection system that incorporates a mass spectrometer to measure high neutron flux in a nuclear reactor environment. This system consists of slow and fast neutron detector elements for measuring fluxes in those energy regions respectively. The detector should further be capable of withstanding the harsh conditions associated with a high temperature reactor. This novel detector which was initially intended for use in the PBMR reactor has possible applications as an in-core neutron and indirect temperature-monitoring device in any of the HTGR. Simulations of a generic HTGR core model were performed in order to obtain the neutron energy spectrum with emphasis on the behavior of three energy regions, slow, intermediate and fast neutrons within the core at different temperatures. The slow neutron flux which has the characteristic of a Maxwell- Boltzmann distribution were found to shift to larger values of neutron flux at higher energies as the fuel temperature increased, while fast neutron flux spectra remained relatively constant. In addition, the results of the fit of the slow neutron flux with a modified Maxwell-Boltzmann equation confirmed that in the presence of the neutron source, leakage and absorption, the effective neutron temperatures is above the medium temperatures. From these results, it was clear that the detection system will need to monitor both slow and fast neutron flux. Placing neutron detectors inside the reactor core, that are sensitive to a particular energy range of slow and fast neutrons, would thus provide information about the change of temperature in the fuel and hence act as an in-core temperature monitor. A detection mechanism was developed that employs the neutron-induced break-up reaction of 6Li and 12C into α-particles. These materials make excellent neutron converters without interference due to γ-rays, as the contributions from 6Li(γ,np)4He and 12C(γ,3α) reactions are negligible. The mass spectrometer measures the 4He partial pressure as a function of time under high vacuum with the help of pressure gradient provided by a high-vacuum turbomolecular pump and a positive-displacement fore-vacuum pump connected in series. A cryogenic trap, which contains a molecular sieve made of pellets 1.6 mm in diameter, was also designed and manufactured to remove impurities which cause a background in the lighter mass region of the spectrum. The development and testing of the high flux neutron detection system were performed at the iThemba Laboratory for Accelerator Based Sciences (LABS), South Africa. These tests were carried out with a high energy proton beam at the D-line neutron facility, and with a fast neutron beam at the neutron radiation therapy facility. To test the principle and capability of the detection system in measuring high fluxes, a high intensity 66 MeV proton beam was used to produce a large yield of α-particles. This was done because the proton inelastic scattering… Advisors/Committee Members: Papka, Paul, Wyngaardt, Shaun M., Dobson, Robert T., Smit, Frederick D., Stellenbosch University. Faculty of Sciences. Dept. of Physics..

Subjects/Keywords: Physics; Neutron physics; Neutron transport; High flux neutron detection systems

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APA (6^th Edition):

Singo, T. D. (2012). Development of a high flux neutron radiation detection system for in-core temperature monitoring. (Doctoral Dissertation). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/19999

Chicago Manual of Style (16^th Edition):

Singo, Thifhelimbilu Daphney. “Development of a high flux neutron radiation detection system for in-core temperature monitoring.” 2012. Doctoral Dissertation, Stellenbosch University. Accessed June 07, 2020. http://hdl.handle.net/10019.1/19999.

MLA Handbook (7^th Edition):

Singo, Thifhelimbilu Daphney. “Development of a high flux neutron radiation detection system for in-core temperature monitoring.” 2012. Web. 07 Jun 2020.

Vancouver:

Singo TD. Development of a high flux neutron radiation detection system for in-core temperature monitoring. [Internet] [Doctoral dissertation]. Stellenbosch University; 2012. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/10019.1/19999.

Council of Science Editors:

Singo TD. Development of a high flux neutron radiation detection system for in-core temperature monitoring. [Doctoral Dissertation]. Stellenbosch University; 2012. Available from: http://hdl.handle.net/10019.1/19999

Addis Ababa University

19. Getu, Ferenji. Measurement of Thermal neutron capture cross section in Sb-121” .

Degree: 2013, Addis Ababa University

URL: http://etd.aau.edu.et/dspace/handle/123456789/1312

► The measurement of thermal neutron cross sections gives basic information about the internal structure of atomic nuclei and their structure. Measurement of Thermal Neutron cross-section… (more)

Subjects/Keywords: Neutron sources; Neutron interaction; Thermal neutron cross section; Slowing down of Neutron,; Neutron Activation analysis; HPGe

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APA (6^th Edition):

Getu, F. (2013). Measurement of Thermal neutron capture cross section in Sb-121” . (Thesis). Addis Ababa University. Retrieved from http://etd.aau.edu.et/dspace/handle/123456789/1312

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):

Getu, Ferenji. “Measurement of Thermal neutron capture cross section in Sb-121” .” 2013. Thesis, Addis Ababa University. Accessed June 07, 2020. http://etd.aau.edu.et/dspace/handle/123456789/1312.

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

MLA Handbook (7^th Edition):

Getu, Ferenji. “Measurement of Thermal neutron capture cross section in Sb-121” .” 2013. Web. 07 Jun 2020.

Vancouver:

Getu F. Measurement of Thermal neutron capture cross section in Sb-121” . [Internet] [Thesis]. Addis Ababa University; 2013. [cited 2020 Jun 07]. Available from: http://etd.aau.edu.et/dspace/handle/123456789/1312.

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

Council of Science Editors:

Getu F. Measurement of Thermal neutron capture cross section in Sb-121” . [Thesis]. Addis Ababa University; 2013. Available from: http://etd.aau.edu.et/dspace/handle/123456789/1312

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

The Ohio State University

20. Turkoglu, Danyal J. Design, Construction and Characterization of an External Neutron Beam Facility at The Ohio State University Nuclear Reactor Laboratory.

Degree: MS, Nuclear Engineering, 2011, The Ohio State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1325228897

► The objective of this research was to bring a thermal neutron beam facility to the Ohio State University Nuclear Reactor Laboratory for the purposes of… (more)

Subjects/Keywords: Nuclear Engineering; neutron beam; neutron; neutron radiography; neutron depth profiling; neutron beam facility; research reactor; MCNP

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APA (6^th Edition):

Turkoglu, D. J. (2011). Design, Construction and Characterization of an External Neutron Beam Facility at The Ohio State University Nuclear Reactor Laboratory. (Masters Thesis). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1325228897

Chicago Manual of Style (16^th Edition):

Turkoglu, Danyal J. “Design, Construction and Characterization of an External Neutron Beam Facility at The Ohio State University Nuclear Reactor Laboratory.” 2011. Masters Thesis, The Ohio State University. Accessed June 07, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1325228897.

MLA Handbook (7^th Edition):

Turkoglu, Danyal J. “Design, Construction and Characterization of an External Neutron Beam Facility at The Ohio State University Nuclear Reactor Laboratory.” 2011. Web. 07 Jun 2020.

Vancouver:

Turkoglu DJ. Design, Construction and Characterization of an External Neutron Beam Facility at The Ohio State University Nuclear Reactor Laboratory. [Internet] [Masters thesis]. The Ohio State University; 2011. [cited 2020 Jun 07]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1325228897.

Council of Science Editors:

Turkoglu DJ. Design, Construction and Characterization of an External Neutron Beam Facility at The Ohio State University Nuclear Reactor Laboratory. [Masters Thesis]. The Ohio State University; 2011. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1325228897

University of Manitoba

21. Das, Moushumi Jr. Highly sensitive Rb magnetometer for neutron electric dipole moment experiments.

Degree: Physics and Astronomy, 2018, University of Manitoba

URL: http://hdl.handle.net/1993/33655

► A non-zero neutron electric dipole moment (nEDM) would indicate time-reversal and charge-parity violation. Our collaboration is developing an experiment at TRIUMF to improve the sensitivity… (more)

Subjects/Keywords: neutron electric dipole moment; neutron electric dipole moment; neutron electric dipole moment

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APA (6^th Edition):

Das, M. J. (2018). Highly sensitive Rb magnetometer for neutron electric dipole moment experiments. (Masters Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/33655

Chicago Manual of Style (16^th Edition):

Das, Moushumi Jr. “Highly sensitive Rb magnetometer for neutron electric dipole moment experiments.” 2018. Masters Thesis, University of Manitoba. Accessed June 07, 2020. http://hdl.handle.net/1993/33655.

MLA Handbook (7^th Edition):

Das, Moushumi Jr. “Highly sensitive Rb magnetometer for neutron electric dipole moment experiments.” 2018. Web. 07 Jun 2020.

Vancouver:

Das MJ. Highly sensitive Rb magnetometer for neutron electric dipole moment experiments. [Internet] [Masters thesis]. University of Manitoba; 2018. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/1993/33655.

Council of Science Editors:

Das MJ. Highly sensitive Rb magnetometer for neutron electric dipole moment experiments. [Masters Thesis]. University of Manitoba; 2018. Available from: http://hdl.handle.net/1993/33655

Royal Holloway, University of London

22. Willis, Toby. Determination of diffusion mechanisms in battery materials using quasi-elastic neutron scattering techniques.

Degree: PhD, 2017, Royal Holloway, University of London

URL: https://pure.royalholloway.ac.uk/portal/en/publications/determination-of-diffusion-mechanisms-in-battery-materials-using-quasielastic-neutron-scattering-techniques(dfe6a3ed-a1f5-40ce-b1b7-fb83ae65e276).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792610

► The diffusion of ions within a battery material is inherently important to its capacity to charge and discharge electrons through a circuit during its normal… (more)

Subjects/Keywords: Battery; Diffusion; density functional theory (DFT); NaCoO2; LiLaTiO3; neutron diffraction; Neutron spectroscopy; Neutron scattering; crystal

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APA (6^th Edition):

Willis, T. (2017). Determination of diffusion mechanisms in battery materials using quasi-elastic neutron scattering techniques. (Doctoral Dissertation). Royal Holloway, University of London. Retrieved from https://pure.royalholloway.ac.uk/portal/en/publications/determination-of-diffusion-mechanisms-in-battery-materials-using-quasielastic-neutron-scattering-techniques(dfe6a3ed-a1f5-40ce-b1b7-fb83ae65e276).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792610

Chicago Manual of Style (16^th Edition):

Willis, Toby. “Determination of diffusion mechanisms in battery materials using quasi-elastic neutron scattering techniques.” 2017. Doctoral Dissertation, Royal Holloway, University of London. Accessed June 07, 2020. https://pure.royalholloway.ac.uk/portal/en/publications/determination-of-diffusion-mechanisms-in-battery-materials-using-quasielastic-neutron-scattering-techniques(dfe6a3ed-a1f5-40ce-b1b7-fb83ae65e276).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792610.

MLA Handbook (7^th Edition):

Willis, Toby. “Determination of diffusion mechanisms in battery materials using quasi-elastic neutron scattering techniques.” 2017. Web. 07 Jun 2020.

Vancouver:

Willis T. Determination of diffusion mechanisms in battery materials using quasi-elastic neutron scattering techniques. [Internet] [Doctoral dissertation]. Royal Holloway, University of London; 2017. [cited 2020 Jun 07]. Available from: https://pure.royalholloway.ac.uk/portal/en/publications/determination-of-diffusion-mechanisms-in-battery-materials-using-quasielastic-neutron-scattering-techniques(dfe6a3ed-a1f5-40ce-b1b7-fb83ae65e276).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792610.

Council of Science Editors:

Willis T. Determination of diffusion mechanisms in battery materials using quasi-elastic neutron scattering techniques. [Doctoral Dissertation]. Royal Holloway, University of London; 2017. Available from: https://pure.royalholloway.ac.uk/portal/en/publications/determination-of-diffusion-mechanisms-in-battery-materials-using-quasielastic-neutron-scattering-techniques(dfe6a3ed-a1f5-40ce-b1b7-fb83ae65e276).html ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.792610

University of Tennessee – Knoxville

23. Yue, Andrew T. Progress Toward a Redetermination of the Neutron Lifetime Through the Absolute Determination of Neutron Flux.

Degree: 2011, University of Tennessee – Knoxville

URL: https://trace.tennessee.edu/utk_graddiss/1243

► The reported lifetime in an in-beam neutron lifetime experiment performed at NIST was tn = (886.3 ± 3.4) s. The largest source of uncertainty was… (more)

Subjects/Keywords: fundamental neutron physics; neutron lifetime; neutron flux; lithium cross section; beam lifetime experiment

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APA (6^th Edition):

Yue, A. T. (2011). Progress Toward a Redetermination of the Neutron Lifetime Through the Absolute Determination of Neutron Flux. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/1243

Chicago Manual of Style (16^th Edition):

Yue, Andrew T. “Progress Toward a Redetermination of the Neutron Lifetime Through the Absolute Determination of Neutron Flux.” 2011. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed June 07, 2020. https://trace.tennessee.edu/utk_graddiss/1243.

MLA Handbook (7^th Edition):

Yue, Andrew T. “Progress Toward a Redetermination of the Neutron Lifetime Through the Absolute Determination of Neutron Flux.” 2011. Web. 07 Jun 2020.

Vancouver:

Yue AT. Progress Toward a Redetermination of the Neutron Lifetime Through the Absolute Determination of Neutron Flux. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2011. [cited 2020 Jun 07]. Available from: https://trace.tennessee.edu/utk_graddiss/1243.

Council of Science Editors:

Yue AT. Progress Toward a Redetermination of the Neutron Lifetime Through the Absolute Determination of Neutron Flux. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2011. Available from: https://trace.tennessee.edu/utk_graddiss/1243

University of Tennessee – Knoxville

24. Harrison, Thomas Jay. Methodology For Generating Simplified Cross Section Data Sets For Neutron Transport Calculations.

Degree: 2015, University of Tennessee – Knoxville

URL: https://trace.tennessee.edu/utk_graddiss/3583

► Neutron shielding problems involve radiation transport calculations over a wide range of energies. Fission neutrons have initial energy on the order of MeV, fusion neutrons… (more)

▼ Neutron shielding problems involve radiation transport calculations over a wide range of energies. Fission neutrons have initial energy on the order of MeV, fusion neutrons have initial energy on the order of 10s of MeV, and space-origin neutrons have initial energy on the order of 100s of MeV or higher. Shielding calculations must track the neutrons from their initial energies until they are no longer of interest; for deep-penetration neutrons, this final energy can be on the order of eV before the neutron is no longer tracked. Thus, for deep-penetration space radiation shielding problems, the calculation may require tracking the neutron energy through eight orders of magnitude. The shielding calculations also require the evaluation of the neutron cross section as a function of the neutron energy. However, the cross section value itself may range from 10-3 barn (1 mb) to nearly 109 barn (1 Gb), a range of twelve orders of magnitude. Further complicating the cross section analysis is the existence of resonance peaks; these peaks (or valleys) may show a change spanning multiple orders of magnitude in cross section value over less than a 1% change in neutron energy. The issue of cross section data sets with multiple resonance peaks can be resolved through the use of flux-weighted group cross sections. The most basic group structure is a single cross section; modern analytical codes can use more than 200 groups, or the full cross section data set itself. However, this introduces a tradeoff of efficiency (fewer groups) versus accuracy (more groups), and it also requires an a priori knowledge of the flux spectrum. This research proposes and tests a method to generate group-wise cross section data sets that do not require the a priori flux spectrum, which is equivalent to assuming a flat flux spectrum distribution. This method conserves the energy-integrated cross sections, which are an inherent characteristic of an isotope, instead of group-wise reaction rates, which are a function of the overall system. The net result is a reduction in calculation time without a significant loss in neutron survival and penetration results and the transmitted and reflected spectra.

Subjects/Keywords: Neutron Cross Section; Neutron Shielding; Monte Carlo Methods; Neutron Flux Spectrum; Nuclear; Nuclear Engineering

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APA (6^th Edition):

Harrison, T. J. (2015). Methodology For Generating Simplified Cross Section Data Sets For Neutron Transport Calculations. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/3583

Chicago Manual of Style (16^th Edition):

Harrison, Thomas Jay. “Methodology For Generating Simplified Cross Section Data Sets For Neutron Transport Calculations.” 2015. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed June 07, 2020. https://trace.tennessee.edu/utk_graddiss/3583.

MLA Handbook (7^th Edition):

Harrison, Thomas Jay. “Methodology For Generating Simplified Cross Section Data Sets For Neutron Transport Calculations.” 2015. Web. 07 Jun 2020.

Vancouver:

Harrison TJ. Methodology For Generating Simplified Cross Section Data Sets For Neutron Transport Calculations. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2015. [cited 2020 Jun 07]. Available from: https://trace.tennessee.edu/utk_graddiss/3583.

Council of Science Editors:

Harrison TJ. Methodology For Generating Simplified Cross Section Data Sets For Neutron Transport Calculations. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2015. Available from: https://trace.tennessee.edu/utk_graddiss/3583

University of Tennessee – Knoxville

25. Taylor, Steven Zachary. Beta-Delayed Neutron Spectroscopy of 135-136Sb Using the Versatile Array of Neutron Detectors at Low Energy (VANDLE).

Degree: 2018, University of Tennessee – Knoxville

URL: https://trace.tennessee.edu/utk_graddiss/5282

► Very neutron rich nuclei decay almost exclusively by β[beta] decay followed by the emission of a delayed neutron. The Versatile Array of Neutron Detectors at… (more)

Subjects/Keywords: beta decay; neutron emission; neutron spectroscopy; beta-delayed neutron decay; nuclear structure; shell model

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APA (6^th Edition):

Taylor, S. Z. (2018). Beta-Delayed Neutron Spectroscopy of 135-136Sb Using the Versatile Array of Neutron Detectors at Low Energy (VANDLE). (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/5282

Chicago Manual of Style (16^th Edition):

Taylor, Steven Zachary. “Beta-Delayed Neutron Spectroscopy of 135-136Sb Using the Versatile Array of Neutron Detectors at Low Energy (VANDLE).” 2018. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed June 07, 2020. https://trace.tennessee.edu/utk_graddiss/5282.

MLA Handbook (7^th Edition):

Taylor, Steven Zachary. “Beta-Delayed Neutron Spectroscopy of 135-136Sb Using the Versatile Array of Neutron Detectors at Low Energy (VANDLE).” 2018. Web. 07 Jun 2020.

Vancouver:

Taylor SZ. Beta-Delayed Neutron Spectroscopy of 135-136Sb Using the Versatile Array of Neutron Detectors at Low Energy (VANDLE). [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2018. [cited 2020 Jun 07]. Available from: https://trace.tennessee.edu/utk_graddiss/5282.

Council of Science Editors:

Taylor SZ. Beta-Delayed Neutron Spectroscopy of 135-136Sb Using the Versatile Array of Neutron Detectors at Low Energy (VANDLE). [Doctoral Dissertation]. University of Tennessee – Knoxville; 2018. Available from: https://trace.tennessee.edu/utk_graddiss/5282

26. Bianchini, Matteo. In situ diffraction studies of electrode materials for Li-ion and Na-ion batteries : Etudes de diffraction in situ pour matériaux d'électrode en batteries Li-ion et Na-ion.

Degree: Docteur es, Chimie. Chimie des solides et sciences des matériaux, 2015, Amiens

URL: http://www.theses.fr/2015AMIE0022

►

Ce travail vise à étudier les matériaux d'électrodes pour batteries Li-ion et Na-ion lors qu’ils fonctionnent à l'intérieur des batteries. Afin de comprendre l'évolution structurelle… (more)

▼

Ce travail vise à étudier les matériaux d'électrodes pour batteries Li-ion et Na-ion lors qu’ils fonctionnent à l'intérieur des batteries. Afin de comprendre l'évolution structurelle des matériaux alors que les ions Li+ ou Na+ sont insérés/extraits de leur cadre, on utilise principalement la diffraction, exploitant neutrons, rayons X et le rayonnement synchrotron (SR). Nous avons adopté une approche combinée des mesures ex situ, in situ et operando. Au début, nous avons conçu une cellule électrochimique pour mesures in situ de diffraction de neutrons sur poudre (NPD), avec un alliage en (Ti,Zr) "transparent aux neutrons"; cette cellule s'est ajoutée à l’ensemble de nos outils pour effectuer des études de type operando. Nous avons démontré leur faisabilité en utilisant LiFePO4, montrant de bonnes performances électrochimiques et des données NPD de haute qualité pour affinements structurales Rietveld. Ensuite, nous avons réalisé des études des spinelles Li1+xMn2-xO4 (x=0,0.05,0.10) et LiNi0.4Mn1.6O4: pendant le cyclage, nous avons rapporté des évolutions structurelles, des diagrammes de phases et paramètres subtils tels que le comportement du Li, ou les facteurs de température. L’utilisation complémentaire du SR a clarifié la nature de la phase ordonnée Li0.5Mn2O4. Nos études combinées ont concernées d’autres matériaux d'électrodes prometteurs: LiVPO4O et Na3V2(PO4)2F3. Les 2 révèle des comportements complexes pendant la (de)intercalation du Li+/Na+. Les données de haute qualité ont permis des analyses quantitatives, dévoilant la structure d'un grand nombre des phases ordonnées et menant à la compréhension du comportement des cations dans ces matériaux

This work aims at studying electrode materials for Li-ion and Na-ion batteries as they function inside batteries. Diffraction is the mainly used technique, exploiting neutrons, X-Rays and synchrotron radiation (SR), to obtain insights on the structural evolution of such materials as Li+ or Na+ are inserted/extracted from their framework. We adopted a combined approach of ex situ, in situ and operando measurements to extract a maximum of information from our studies. At first, we designed an electrochemical cell for in situ neutron powder diffraction (NPD) measurements, featuring a “neutron-transparent” (Ti,Zr) alloy; this cell, joined to others previously developed in our group, gave us a complete set of tools to perform our studies. We demonstrated the feasibility of operando NPD using LiFePO4, showing good electrochemical performances and high-quality NPD patterns for Rietveld structural refinements. Then we carried out detailed studies of spinels Li1+xMn2-xO4 (x = 0, 0.05, 0.10) and LiNi0.4Mn1.6O4: we reported phase diagrams, structural evolutions and subtle parameters as lithium's behavior inside the spinel framework, or thermal displacement parameters, directly upon cycling. Complementary use of SR shed light on other features, as the nature of the ordered phase Li0.5Mn2O4. Our combined studies concerned other promising electrode materials: LiVPO4O and…

Advisors/Committee Members: Masquelier, Christian (thesis director).

Subjects/Keywords: Neutron; Crystal structures; 540

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APA (6^th Edition):

Bianchini, M. (2015). In situ diffraction studies of electrode materials for Li-ion and Na-ion batteries : Etudes de diffraction in situ pour matériaux d'électrode en batteries Li-ion et Na-ion. (Doctoral Dissertation). Amiens. Retrieved from http://www.theses.fr/2015AMIE0022

Chicago Manual of Style (16^th Edition):

Bianchini, Matteo. “In situ diffraction studies of electrode materials for Li-ion and Na-ion batteries : Etudes de diffraction in situ pour matériaux d'électrode en batteries Li-ion et Na-ion.” 2015. Doctoral Dissertation, Amiens. Accessed June 07, 2020. http://www.theses.fr/2015AMIE0022.

MLA Handbook (7^th Edition):

Bianchini, Matteo. “In situ diffraction studies of electrode materials for Li-ion and Na-ion batteries : Etudes de diffraction in situ pour matériaux d'électrode en batteries Li-ion et Na-ion.” 2015. Web. 07 Jun 2020.

Vancouver:

Bianchini M. In situ diffraction studies of electrode materials for Li-ion and Na-ion batteries : Etudes de diffraction in situ pour matériaux d'électrode en batteries Li-ion et Na-ion. [Internet] [Doctoral dissertation]. Amiens; 2015. [cited 2020 Jun 07]. Available from: http://www.theses.fr/2015AMIE0022.

Council of Science Editors:

Bianchini M. In situ diffraction studies of electrode materials for Li-ion and Na-ion batteries : Etudes de diffraction in situ pour matériaux d'électrode en batteries Li-ion et Na-ion. [Doctoral Dissertation]. Amiens; 2015. Available from: http://www.theses.fr/2015AMIE0022

Penn State University

27. Idrisy, Ashikuzzaman. Searching for gravitational waves from neutron stars.

Degree: PhD, Physics, 2014, Penn State University

URL: https://etda.libraries.psu.edu/catalog/24255

► In this dissertation we discuss gravitational waves (GWs) and their neutron star (NS) sources. We begin with a general discussion of the motivation for searching… (more)

▼ In this dissertation we discuss gravitational waves (GWs) and their neutron star (NS) sources. We begin with a general discussion of the motivation for searching for GWs and the indirect experimental evidence of their existence. Then we discuss the various mechanisms through which NS can emit GWs, paying special attention the r-mode oscillations. Finally we end with discussion of GW detection. In Chapter 2 we describe research into the frequencies of r-mode oscillations. Knowing these frequencies can be useful for guiding and interpreting gravitational wave and electromagnetic observations. The frequencies of slowly rotating, barotropic, and non-magnetic Newtonian stars are well known, but subject to various corrections. After making simple estimates of the relative strengths of these corrections we conclude that relativistic corrections are the most important. For this reason we extend the formalism of K. H. Lockitch, J. L. Friedman, and N. Andersson [Phys. Rev. D 68, 124010 (2003)], who consider relativistic polytropes, to the case of realistic equations of state. This formulation results in perturbation equations which are solved using a spectral method. We find that for realistic equations of state the r-mode frequency ranges from 1.39–1.57 times the spin frequency of the star when the relativistic compactness parameter (M/R) is varied over the astrophysically motivated interval 0.110–0.310. Following a successful r-mode detection our results can help constrain the high density equation of state. In Chapter 3 we present a technical introduction to the data analysis tools used in GW searches. Starting from the plane-wave solutions derived in Chapter 1 we develop the F-statistic used in the matched filtering technique. This technique relies on coherently integrating the GW detector’s data stream with a theoretically modeled wave signal. The statistic is used to test the null hypothesis that the data contains no signal. In this chapter we also discuss how to generate the parameter space of a GW search so as to cover the largest physical range of parameters, while keeping the search computationally feasible. Finally we discuss the timedomain solar system barycentered resampling algorithm as a way to improve to the computational cost of the analysis. In Chapter 4 we discuss a search for GWs from two supernova remnants, G65.7 and G330.2. The searches were conducted using data from the 6th science run of the LIGO detectors. Since the searches were modeled on the Cassiopeia A search paper, Abadie et. al. [Astrophys. J. 722,1504–1513, 2010], we also used the frequency and the first and second derivatives of the frequency as the parameter space of the search. There are two main differences from the previous search. The first is the use of the resampling algorithm, which sped up the calculation of the F-statistic by a factor of 3 and thus allowed for longer stretches of data to be coherently integrated. Being able to integrate more data meant that we could beat the indirect limit on GWs expected from these sources. We used…

Subjects/Keywords: neutron stars; gravitational waves

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APA (6^th Edition):

Idrisy, A. (2014). Searching for gravitational waves from neutron stars. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/24255

Chicago Manual of Style (16^th Edition):

Idrisy, Ashikuzzaman. “Searching for gravitational waves from neutron stars.” 2014. Doctoral Dissertation, Penn State University. Accessed June 07, 2020. https://etda.libraries.psu.edu/catalog/24255.

MLA Handbook (7^th Edition):

Idrisy, Ashikuzzaman. “Searching for gravitational waves from neutron stars.” 2014. Web. 07 Jun 2020.

Vancouver:

Idrisy A. Searching for gravitational waves from neutron stars. [Internet] [Doctoral dissertation]. Penn State University; 2014. [cited 2020 Jun 07]. Available from: https://etda.libraries.psu.edu/catalog/24255.

Council of Science Editors:

Idrisy A. Searching for gravitational waves from neutron stars. [Doctoral Dissertation]. Penn State University; 2014. Available from: https://etda.libraries.psu.edu/catalog/24255

Penn State University

28. Gill, Daniel Fury. Newton-Krylov Methods for the Solution of the k-Eigenvalue Problem in Multigroup Neutronics Calculations.

Degree: PhD, Nuclear Engineering, 2009, Penn State University

URL: https://etda.libraries.psu.edu/catalog/10162

► In this work we propose using Newton's method, specifically the inexact Newton-GMRES formulation, to solve the k-eigenvalue problem in both transport and diffusion neutronics problems.… (more)

▼ In this work we propose using Newton's method, specifically the inexact Newton-GMRES formulation, to solve the k-eigenvalue problem in both transport and diffusion neutronics problems. This is achieved by choosing a nonlinear function whose roots are the eigenpairs of the k-eigenvalue calculation and then using Newton's method to solve the nonlinear system. The flexibility resulting from the use of a Krylov subspace method to solve the linear Newton step can be further extended via the use of the Jacobian-Free Newton-Krylov (JFNK) approximation, which requires no knowledge of the system's Jacobian; instead only the ability to evaluate the system residual is necessary. This makes it possible to avoid the computational and memory costs associated with the construction and storage of the Jacobian, resulting in an efficient solution algorithm. Writing the k-eigenvalue problem as a nonlinear function yields a number of formulations, all of which all have the desired roots. For the diffusion approximation, the nonlinear function is written in the form of the generalized eigenvalue problem and a set of preconditioners is developed and applied to the GMRES iterations that are used to solve the linearized Newton problem. Most of the developed methods can be implemented as either Newton-Krylov (NK) methods, where the Jacobian-vector product is formed using the explicitly constructed Jacobian, or via the JFNK approximation, where a finite-difference perturbation is used to approximate the Jacobian-vector product. One particularly effective preconditioning option comprises the use of the standard power iteration to precondition the GMRES iteration on either the right or the left. Preconditioning on the left, denoted JFNK(PI), results in a modified nonlinear system whose implementation only requires the ability to perform a single traditional outer iteration, making this approach relatively simple to wrap around an existing diffusion theory k-eigenvalue problem solver. Other preconditioning options, such as the Incomplete Cholesky decomposition of the within-group diffusion matrix, are also considered. Similar methods were developed for transport theory, cast using an operator notation that greatly simplifies their presentation. All of the nonlinear functions developed are written in terms of a generic fixed-point iteration, with a number of specific fixed-point formulations considered. Each fixed-point scheme represents a viable k-eigenvalue problem solution method, with two of the techniques corresponding to traditionally used iterative schemes. The new methods developed can also be wrapped around existing software in most instances, simplifying the implementation process. Ultimately it is seen that the most effective of the Newton formulations in transport theory is wrapped around a k-eigenvalue formulation that is a very special instance of traditional methods: no upscattering iterations are performed, only one inner iteration completed per outer, using source iteration with the previous outer iterate as the initial guess.…

Subjects/Keywords: JFNK; Criticality; Neutron transport; eigenvalue

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APA (6^th Edition):

Gill, D. F. (2009). Newton-Krylov Methods for the Solution of the k-Eigenvalue Problem in Multigroup Neutronics Calculations. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/10162

Chicago Manual of Style (16^th Edition):

Gill, Daniel Fury. “Newton-Krylov Methods for the Solution of the k-Eigenvalue Problem in Multigroup Neutronics Calculations.” 2009. Doctoral Dissertation, Penn State University. Accessed June 07, 2020. https://etda.libraries.psu.edu/catalog/10162.

MLA Handbook (7^th Edition):

Gill, Daniel Fury. “Newton-Krylov Methods for the Solution of the k-Eigenvalue Problem in Multigroup Neutronics Calculations.” 2009. Web. 07 Jun 2020.

Vancouver:

Gill DF. Newton-Krylov Methods for the Solution of the k-Eigenvalue Problem in Multigroup Neutronics Calculations. [Internet] [Doctoral dissertation]. Penn State University; 2009. [cited 2020 Jun 07]. Available from: https://etda.libraries.psu.edu/catalog/10162.

Council of Science Editors:

Gill DF. Newton-Krylov Methods for the Solution of the k-Eigenvalue Problem in Multigroup Neutronics Calculations. [Doctoral Dissertation]. Penn State University; 2009. Available from: https://etda.libraries.psu.edu/catalog/10162

Penn State University

29. Durrant, Chad Breathauer. Characterization of Italian tile samples using comparative neutron activation analysis in the Penn State Breazeale Nuclear Reactor.

Degree: MS, Nuclear Engineering, 2014, Penn State University

URL: https://etda.libraries.psu.edu/catalog/21255

► Comparative neutron activation analysis (CNAA) is a powerful method that is used to determine trace element compositions of unknown samples by comparing them with known… (more)

▼ Comparative neutron activation analysis (CNAA) is a powerful method that is used to determine trace element compositions of unknown samples by comparing them with known samples. This is accomplished by the activation of the samples with thermal neutrons and then subsequently measuring the corresponding delayed gamma rays. There are three principal goals achieved from this research: developing an irradiation fixture with suitable neutron fluences and large sample number capacity, characterizing the thermal neutron flux of the irradiation fixture, and determining the trace element composition of 15 Italian tiles. The Italian tiles come from two archeological sites, Tarquinia and Veii in Italy. By determining the trace element composition of the samples, the tiles can be separated into groups based on their composition. Archeologists then use the composition data to determine where material used to make these tiles and other similar artefacts originated from. Once the origins of these samples are determined other conclusions such as trade and technology transfer in the region can be drawn. In order to use CNAA at the Radiation Science and Engineering Center to determine the trace element composition of 15 Italian tile samples, an irradiation fixture and sample holder were designed and built for the Penn State Breazeale Reactor (PSBR). This sample holder allows up to 28 samples to be irradiated simultaneously at relatively similar thermal neutron fluences. A short irradiation with a total neutron fluence of ~ 6.1 x 10¹⁴ neutrons/cm2 and a long irradiation with total neutron fluence of ~ 5.8 x 10¹⁷ neutrons/cm² were performed. The irradiation fixture is also durable and made mostly with high purity aluminum, thereby minimizing the impurities that can increase the activity of the sample holder across multiple irradiations. An encapsulation method for the samples was developed using high purity quartz ampoules to minimize the interferences in the gamma spectra as well as minimize the activity produced. The thermal and epithermal neutron flux profile of the sample holder was characterized using bare gold-aluminum wires and cadmium covered gold-aluminum wires. The total variation from highest to lowest thermal neutron flux was ~30%. Lastly, the trace element compositions of the 15 Italian tile samples were determined by CNAA. Between 13 and 16 trace elements were determined for each sample including: sodium, potassium, manganese, strontium, europium, scandium, titanium, chromium, iron, zinc, rubidium, antimony, barium, hafnium, calcium, and zirconium. The concentrations of the trace elements determined ranged from hundreds of part per billion (ppb) for antimony to tens of milligrams per gram for potassium, titanium, and iron. All other trace elements had concentrations within that range. After the trace element compositions for each sample were determined, the samples were analyzed and clustered into two groups of similar composition. Group 1 is composed of samples 139B-148B and Group 2 is composed of samples 149B-153B.…

Subjects/Keywords: neutron activation analysis; comparative NAA

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

APA (6^th Edition):

Durrant, C. B. (2014). Characterization of Italian tile samples using comparative neutron activation analysis in the Penn State Breazeale Nuclear Reactor. (Masters Thesis). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/21255

Chicago Manual of Style (16^th Edition):

Durrant, Chad Breathauer. “Characterization of Italian tile samples using comparative neutron activation analysis in the Penn State Breazeale Nuclear Reactor.” 2014. Masters Thesis, Penn State University. Accessed June 07, 2020. https://etda.libraries.psu.edu/catalog/21255.

MLA Handbook (7^th Edition):

Durrant, Chad Breathauer. “Characterization of Italian tile samples using comparative neutron activation analysis in the Penn State Breazeale Nuclear Reactor.” 2014. Web. 07 Jun 2020.

Vancouver:

Durrant CB. Characterization of Italian tile samples using comparative neutron activation analysis in the Penn State Breazeale Nuclear Reactor. [Internet] [Masters thesis]. Penn State University; 2014. [cited 2020 Jun 07]. Available from: https://etda.libraries.psu.edu/catalog/21255.

Council of Science Editors:

Durrant CB. Characterization of Italian tile samples using comparative neutron activation analysis in the Penn State Breazeale Nuclear Reactor. [Masters Thesis]. Penn State University; 2014. Available from: https://etda.libraries.psu.edu/catalog/21255

Texas A&M University

30. Gonzalez, Yesenia Amanda. Deconvoluting an Americium-Beryllium Neutron Spectrum from a Proton Recoil Detector.

Degree: MS, Nuclear Engineering, 2016, Texas A&M University

URL: http://hdl.handle.net/1969.1/158958

► A proton recoil detector was acquired from LND, Inc. to be used in neutron counting experiments with an 241AmBe source. Neutrons elastically scatter off of… (more)

Subjects/Keywords: neutron detection; proton recoil detector

Record Details Similar Records Cite « Share

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

APA (6^th Edition):

Gonzalez, Y. A. (2016). Deconvoluting an Americium-Beryllium Neutron Spectrum from a Proton Recoil Detector. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/158958

Chicago Manual of Style (16^th Edition):

Gonzalez, Yesenia Amanda. “Deconvoluting an Americium-Beryllium Neutron Spectrum from a Proton Recoil Detector.” 2016. Masters Thesis, Texas A&M University. Accessed June 07, 2020. http://hdl.handle.net/1969.1/158958.

MLA Handbook (7^th Edition):

Gonzalez, Yesenia Amanda. “Deconvoluting an Americium-Beryllium Neutron Spectrum from a Proton Recoil Detector.” 2016. Web. 07 Jun 2020.

Vancouver:

Gonzalez YA. Deconvoluting an Americium-Beryllium Neutron Spectrum from a Proton Recoil Detector. [Internet] [Masters thesis]. Texas A&M University; 2016. [cited 2020 Jun 07]. Available from: http://hdl.handle.net/1969.1/158958.

Council of Science Editors:

Gonzalez YA. Deconvoluting an Americium-Beryllium Neutron Spectrum from a Proton Recoil Detector. [Masters Thesis]. Texas A&M University; 2016. Available from: http://hdl.handle.net/1969.1/158958

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