Electronic Structure Of Lithium Tetraborate,
2010
Air Force Institute of Technology
Electronic Structure Of Lithium Tetraborate, David J. Wooten
Theses and Dissertations
Due to interest as neutron detection material, an investigation of Li2B4O7(110) and Li2B4O7(100) was undertaken, utilizing photoemission and inverse photoemission spectroscopic techniques. The measured band gap depended on crystallographic direction with the band gaps ranging from 8.9±0.5 eV to 10.1±0.5 eV. The measurement yielded a density of states that qualitatively agreed with the theoretical results from model bulk band structure calculations for Li2B4O7; albeit with a larger band gap than predicted, but consistent with the known deficiencies of LDA and DFT calculations. …
Synthesis Of Meta-Terphenyl Scaffolded Molecules For Catalysis And Sensor Applications,
2010
Clemson University
Synthesis Of Meta-Terphenyl Scaffolded Molecules For Catalysis And Sensor Applications, Brad Morgan
All Dissertations
The utility of the m-terphenyl has been observed in a wide variety of applications since its first discovery. The tunable conformational flexibility contributes to the unique properties and resulting applications thereof. Chapter 1 goes into detail about the concepts used throughout and defines the tools needed to understand the chemistry in the
resulting chapters.
The primary use of the m-terphenyl herein is as a canopy that shields a pocket created underneath the central ring. Functionalization within this pocket allows metal binding in defined coordination environments. with the use of donor ligands attached to the flanking rings. The applications of these …
Classification, Synthesis And Characterization Of Pyridyl Porphyrin Frameworks,
2010
University of Nebraska-Lincoln
Classification, Synthesis And Characterization Of Pyridyl Porphyrin Frameworks, Lucas D. Devries
Department of Chemistry: Dissertations, Theses, and Student Research
Structural analysis of a solid-state material is vital because the structure often determines the physical (or chemical) properties of the material. An understanding of the relationship between structural components and bulk properties can be used to design materials with specific properties. To achieve such understanding, two things are required: a rigorous structural analysis method and a study of the properties of materials with noteworthy structural features. In this thesis, the author reviews 44 pyridyl porphyrin frameworks in an effort to determine how these framework structures are formed, and if any overreaching trends can be observed. The observed trends are used …
The Reaction Of A Water Soluble Platinum Compound With Methionine And Derivatives,
2010
Western Kentucky University
The Reaction Of A Water Soluble Platinum Compound With Methionine And Derivatives, Yueh Ying Liao
Masters Theses & Specialist Projects
Water soluble platinum complexes are a recent area of emphasis of cisplatin chemistry. The water soluble complexes could have a reduced toxicity compared with cisplatin. Oxaliplatin, which has an oxalate leaving group, has previously been shown to have less nephro-toxicity and higher water solubility than cisplatin. [Pt(en)(oxalate)] (en = ethylenediamine) has been prepared from Pt(en)Cl2 and silver oxalate. This complex has been reacted with methionine and N-acetylmethionine at different molar ratios. At high Pt: methionine ratios, chelates with the sulfur and nitrogen atoms of the methionine are dominant; at lower Pt: methionine ratios, a bis-methionine product is formed. The en …
The Material Properties Of Cssnbr3 And Csbr:Sn-1% And Their Potential As Scintillator Detector Material,
2010
Air Force Institute of Technology
The Material Properties Of Cssnbr3 And Csbr:Sn-1% And Their Potential As Scintillator Detector Material, Neal B. Kleinschmidt
Theses and Dissertations
The search for superior nuclear radiation detection materials is ongoing. Current scintillator materials using Thallium doped Sodium Iodide or Cesium Iodide are the benchmarks for ease of use and quick identification of isotope species. This research aims to explore Cesium Bromide doped with 1% molar tin (CsBr:Sn-1%) and Cesium Tin Bromide (CsSnBr3) as candidate materials for a new scintillator. The techniques of Extended X-Ray Absorption Fine Structure (EXAFS), X-Ray Absorption Near Edge Structure (XANES) and Cathodoluminescence are used to determine the suit- ability of CsSnBr3 and CsBr:Sn-1% with Sn4+ as a potential scintillator materials and explore their …
Improved Modeling Of Midlatitude D-Region Ionospheric Absorption Of High Frequency Radio Signals During Solar X-Ray Flares,
2010
Air Force Institute of Technology
Improved Modeling Of Midlatitude D-Region Ionospheric Absorption Of High Frequency Radio Signals During Solar X-Ray Flares, Evelyn A. Schumer
Theses and Dissertations
The purpose of this research was to improve modeling of midlatitude D-region ionospheric absorption of high frequency radio signals during solar X-ray flares through analysis of HF propagation data obtained during the HF Investigation of D-region Ionospheric Variation Experiment (HIDIVE) and obtained at the Canadian Space Agency NORSTAR riometer in Pinawa, Manitoba, Canada and X-ray flux data, as reported by GOES satellites. The findings of the data analysis were then used to validate and suggest improvements for two existing HF absorption models, the operational Space Weather Prediction Center (SWPC) D-region Absorption model and the physical AbbyNormal model. Analysis of the …
Three Dimensional Positron Annihilation Momentum Measurement Technique (3dpamm) Applied To Measure Oxygen-Atom Defects In 6h Silicon Carbide,
2010
Air Force Institute of Technology
Three Dimensional Positron Annihilation Momentum Measurement Technique (3dpamm) Applied To Measure Oxygen-Atom Defects In 6h Silicon Carbide, Christopher S. Williams
Theses and Dissertations
A three-dimensional Positron Annihilation Spectroscopy System (3DPASS) capable to simultaneously measure three-dimensional electron-positron (e--e+) momentum densities measuring photons derived from e--e+ annihilation events was designed and characterized. 3DPASS simultaneously collects a single data set of correlated energies and positions for two coincident annihilation photons using solid-state double-sided strip detectors (DSSD). Positions of photons were determined using an interpolation method which measures a figure-of-merit proportional to the areas of transient charges induced on both charge collection strips directly adjacent to the charge collection strips interacting with the annihilation photons. The subpixel resolution was measured for both double-sided …
Optical Properties Of Si, Ge, Gaas, Gasb, Inas, And Inp At Elevated Temperatures,
2010
Air Force Institute of Technology
Optical Properties Of Si, Ge, Gaas, Gasb, Inas, And Inp At Elevated Temperatures, Thomas R. Harris
Theses and Dissertations
Investigation of the optical and electrical behavior of some semiconductors at very high temperatures has not been an area of much study, at least not experimentally. The importance of such research becomes obvious due to the effects of high temperatures on semiconductor devices such as infrared detectors and light emitters. Besides the destructive effects of thermal stress and melting, changes in the optical properties of the material can greatly affect device performance. In this research, the infrared absorption of Si, Ge, GaAs, GaSb, InAs, and InP was measured from 0.6 to 25 μm at temperatures ranging from 295 up to …
Experimental Validation Techniques For The Heleeos Off-Axis Laser Propagation Model,
2010
Air Force Institute of Technology
Experimental Validation Techniques For The Heleeos Off-Axis Laser Propagation Model, John D. Haiducek
Theses and Dissertations
The High Energy Laser End-to-End Operational Simulation (HELEEOS) off-axis scattering algorithm is designed to predict the irradiance that will be detected at a given off-axis location due to atmospheric scattering of a high-energy laser. The HELEEOS system models the propagation of the laser through the atmosphere, accounting for such effects as turbulence, thermal blooming, and atmospheric absorption. The HELEEOS off-axis scattering algorithm uses the scattering phase functions of the Mie scattering models to predict the amount of radiation that will be scattered toward a particular observation location from each point along the beam path, and the total irradiance that will …
Changes To Electrical Conductivity In Irradiated Carbon-Nickel Nanocomposites,
2010
Air Force Institute of Technology
Changes To Electrical Conductivity In Irradiated Carbon-Nickel Nanocomposites, David F. Coy
Theses and Dissertations
Pre and post irradiation resistivity and XAFS measurements have been conducted to examine the effects of 0.5 MeV electron irradiations on nickel-carbon composites. Results showed a decrease in surface resistivity in all sample types of 14-30% following irradiation with a total electron exposure of 4 x 10-16 cm-2. Results also showed a corresponding decrease in NiO content for the irradiated samples as compared to measurements of non-irradiated samples. Surface resistivity measurement capabilities were established and measurement techniques refined to produce repeatable results of sufficient precision to discern changes in resistivity for an exposure of 2 x 10 …
In-Situ, Gate Bias Dependent Study Of Neutron Irradiation Effects On Algan/Gan Hfets,
2010
Air Force Institute of Technology
In-Situ, Gate Bias Dependent Study Of Neutron Irradiation Effects On Algan/Gan Hfets, Janusz K. Mikina
Theses and Dissertations
AlGaN/GaN Heterostructure Field Effect Transistors (HFETs) have come under increased study in recent years due to their highly desirable material and electrical properties and survivability even during and after exposure to extreme temperature and radiation environments. In this study, unpassivated and SiN passivated Al0.27Ga0.73N/GaN HFETs were subjected to neutron radiation at 120 K. The primary focus of the research was the effects of neutron irradiation on drain current, gate leakage current, threshold voltage shift, gate-channel capacitance, and the effects of biasing the gate during irradiation. In-situ measurements were conducted on transistor current, gate-channel capacitance, and gate …
Conformations Of A Model Protein Revealed By An Aggregating Cuᴵᴵ Porphyrin: Sensing The Difference,
2010
Swarthmore College
Conformations Of A Model Protein Revealed By An Aggregating Cuᴵᴵ Porphyrin: Sensing The Difference, G. De Luca, A. Romeo, L. M. Scolaro, Robert F. Pasternack
Chemistry & Biochemistry Faculty Works
Aggregated t-CuP binds to poly-L-glutamate through supramolecular interactions, revealing itself to be an extremely sensitive probe for the major conformations of the polymeric scaffold.
Experimental And Theoretical Analysis Of The Electronic Behavior In Five-Coordinate Iron(Iii) And Six-Coordinate Cobalt(Iii) Complexes With Electroactive Phenol-Rich Ligands,
2010
Wayne State University
Experimental And Theoretical Analysis Of The Electronic Behavior In Five-Coordinate Iron(Iii) And Six-Coordinate Cobalt(Iii) Complexes With Electroactive Phenol-Rich Ligands, Marco Mathieu Allard
Wayne State University Dissertations
Three 5 coordinate high-spin Iron(III) complexes containing pentadentate N2O5 ligands were synthesized and characterized, namely, (1) [FeIII(L1)] and (2) [FeIII(L2)]. Structural differences in ligand design,N,N,N'-tris(3,5-di-tert-butyl-2-hydroxybenzyl)benzene-1,2-diamine for (1) and N,N,N'-tris-(3,5-di-tert-butyl-2-hydroxybenzyl)-N'-methyl-benzene-1,2-diamine for (2), result in complexes that due to their forced geometry, asymmetry, and slightly different electronic structures are able to foster phenoxyl radicals although show a sensitive dependence to both the solvent and the electrolyte system in the cyclic voltammetry. In the presence of TBAClO4 (1) exhibits a two-electron oxidation, whereas in the presence of TBAPF6 (2), , shows three distinct phenolato/phenoxyl radical couples. Both (1) and (2) were redox-cycled 30 …
Synthetic Levers Enabling Control Of Phase, Size And Morphology In Transition Metal Phosphide Nanoparticles (Fe, Ni),
2010
Wayne State University
Synthetic Levers Enabling Control Of Phase, Size And Morphology In Transition Metal Phosphide Nanoparticles (Fe, Ni), Elayaraja Muthuswamy
Wayne State University Dissertations
ABSTRACT
SYNTHETIC LEVERS ENABLING CONTROL OF PHASE, SIZE AND MORPHOLOGY IN TRANSITION METAL PHOSPHIDE NANOPARTICLES (FE, NI)
by
ELAYARAJA MUTHUSWAMY
May 2011
Advisor:Dr. Stephanie L. Brock
Major: Chemistry
Degree: Doctor of Philosophy
This dissertation study focuses on (1) development of a synthetic strategy to control phase in nanoscale iron phosphides; (2) extension of the developed phase control strategy to the nanoscale nickel phosphide system with simultaneous control on size and morphology and (3) illustration of the enhanced reactivity of nanoscale oxide systems.
A synthetic strategy to control phase in nanoscale iron phosphides was developed to prepare phase-pure samples of …
Metal Chalcogenide Nanocrystal Assembly: From Synthesis To Applications,
2010
Wayne State University
Metal Chalcogenide Nanocrystal Assembly: From Synthesis To Applications, Qinghong Yao
Wayne State University Dissertations
This dissertation study is focused on (1) the application of an oxidation-induced sol-gel assembly method to formation of CdTe aerogels; (2) extension of existing aerogel compositions and properties by an alternative synthetic approach: cation-exchange reactions; and (3) probing the functionality of CdSe aerogels as optical sensors of Lewis base analytes.
Highly porous CdTe aerogels were successfully synthesized by sol-gel assembly of CdTe nanocrystals with thiolate or nonthiolate (phosphine oxide) ligated surfaces by treatment with tetranitromethane. Both phosphine oxide-capped and the thiolate-capped aerogels exhibit similar structure, morphology and porosimetry properties, suggesting that precursor ligation does not have a no major effect …
Synthesis And Characterization Of Metal Complexes Containing Tetrazolate, Poly(Tetrazolyl)Borate, And Aryl Pentazole Ligands As High Energy Density Materials,
2010
Wayne State University
Synthesis And Characterization Of Metal Complexes Containing Tetrazolate, Poly(Tetrazolyl)Borate, And Aryl Pentazole Ligands As High Energy Density Materials, Dongmei Lu
Wayne State University Dissertations
Heavier alkaline earth metal tetrazolates have been prepared as cryatals contain aqua ligands and as anhydrous powders, and were characterized by spectral and analytical methods. Potassium bis(tetrazolyl)borate complexes K(BH2(RCN4)2)(H2O)n (R = H, Me, NMe2, and NiPr2) and their 18-crown-6 adducts have been synthesized. In the solid state, complexes where R = H and Me have B-N bonds to the nitrogen atoms proximal to the carbon atom, whereas those with R = NMe2 and NiPr2 possess isomeric B-N bonds to the nitrogen atoms distal to the …
The Synthesis, Structure, And Properties Of Group 2 Poly(Pyrazolyl)Borates And Their Use For The Atomic Layer Deposition Of Group 2 Borates,
2010
Wayne State University
The Synthesis, Structure, And Properties Of Group 2 Poly(Pyrazolyl)Borates And Their Use For The Atomic Layer Deposition Of Group 2 Borates, Mark J. Saly
Wayne State University Dissertations
A series of heavy alkaline earth complexes containing TpR2-based ligands has been synthesized, structurally characterized, and their properties were investigated. Salt metathesis routes involving MI2 (M = Ca, Sr, Ba) with either KTpEt2 or KTpnPr2 afforded MTpEt22 or MTpnPr22 in good to moderate yields. All of these complexes are volatile and exceptionally thermally stable, and have acceptable properties for use as group 2 atomic layer deposition (ALD) precursors. In addition, a series of group 2 complexes containing BpR2-based ligand systems were synthesized. Treatment of MI2 (M = Ca, Sr, Ba) with two equivalents of TlBptBu2, KBp, and KBpiPr2 in tetrahydrofuran …
Samuel J. Danishetsky And The Synthesis Of Globo-H Antigen,
2010
Parkland College
Samuel J. Danishetsky And The Synthesis Of Globo-H Antigen, Chelsey Jones
Natural Sciences Student Research Presentations
Samuel J. Danishefsky is a research scientist at the Sloan-Kettering Institute. He uses his knowledge in organic chemistry to make biological advances in cancer research. Danishefsky has been conducting research and experiments on synthesizing anti-cancer vaccines with the use of carbohydrate antigens. Danishefsky has also been conducting research and experiments on homogeneous erythropoietin which could provide insight into how glycoproteins function. Knowledge of glycoprotein would allow scientists to better understand erythropoietin which can treat anemia in chemotherapy patients. All is valuable information in advances in cancer research and cancer research is important because it is a major disease affecting the …
Development Of Metal-Based Luminescent Probes For Applications In Biomolecular Structure And Dynamics,
2010
University of Montana
Development Of Metal-Based Luminescent Probes For Applications In Biomolecular Structure And Dynamics, Ayesha Sharmin
Graduate Student Theses, Dissertations, & Professional Papers
New transition-metal complexes containing luminescent properties have been designed and synthesized for application as structural probes for biomolecules. Potential DNA intercalators, 2- amino-anthracene substituted triosmium clusters, were synthesized by the reactions of 2-aminoanthracene with [Os3(CO)10(CH3CN)2]. The products [Os3(CO)10(μ-η2-(N-C(1))-NH2C14H8)(μ- H)], [Os3(CO)10(μ-η2-(N-C(3))-NHC14H9)(μ-H)], [Os3(CO)9(μ-η2-(N-C(3))-NHC14H8)(μ-H)2] and [Os3(CO)9(μ3-η2-(N-C(3))-NHC10H9)(μ-H)] obtained from this reaction have been structurally characterized by spectroscopic, photophysical and electrochemical techniques. Solid state structures are also reported for the complexes [Os3(CO)10(μ-η2-(N-C(3))-NHC14H9)(μ-H)] and [Os3(CO)9(μ-η2-(N-C(3))-NHC14H8)(μ-H)2]. To investigate bio-macromolecular dynamics on the sub-microsecond-to-microsecond timescale, a series of ruthenium based mono-nuclear metalligand charge-transfer complexes (MLCs) of formula [XRu(CO)(L–L)(L′)2][PF6] (X = H, TFA, Cl; L–L = 2,2′-bipyridyl, 1,10-phenanthroline, 5-amino-1,10-phenanthroline …
Heterometallic Beta-Diketonates And Oxo-Diketonates As Single Source Precursors For The Synthesis Of Oxide Materials,
2010
University at Albany, State University of New York
Heterometallic Beta-Diketonates And Oxo-Diketonates As Single Source Precursors For The Synthesis Of Oxide Materials, Haitao Zhang
Legacy Theses & Dissertations (2009 - 2024)
The focus of this investigation was to develop a simple, high-yield synthetic approach to heterometallic diketonates using the same construction principles as for their polynuclear homometallic analogs. Several low-temperature solid-state synthetic routes were suggested that appear to be general for the preparation of heterometallic diketonates incorporating a wide range of s-, p-, d-, and f-metals. Using this investigative approach, two families of bimetallic homoleptic diketonates that contain heavy main group (BiIII, PbII) and the first row divalent transition metals (Mn, Fe, Co, Ni, Cu, and Zn) have been obtained. The heterometallic molecules that are held together by strong Lewis acid-base …
