The authors present the results of the search for the decays B{sup 0/{+-}} {yields} {rho}{sup 0/{+-}}{gamma} (previously observed) and B{sup 0} {yields} {omega}{gamma} (for which currently only an upper limit exists). Together with B {yields} K*{gamma} decays, B {yields} ({rho}/{omega}){gamma} allow us to measure the ratio of CKM-matrix elements |V{sub td}/V{sub ts}|. The analysis is based on the full BABAR dataset of 424.35 fb{sup -1} corresponding to 465 million B{bar B} pairs, and makes heavy use of multivariate classification techniques based on decision trees. They find {Beta}(B{sup {+-}} {yields} {rho}{sup {+-}}{gamma}) = (1.20{sub -0.38}{sup +0.42} {+-} 0.20) x 10{sup -6}, {Beta}(B{sup 0} {yields} {rho}{sup 0}{gamma}) = (0.95{sub -0.21}{sup +0.23} {+-} 0.06) x 10{sup -6}, {Beta}(B{sup 0} {yields} {omega}{gamma}) = (0.51{sub -0.24}{sup +0.27} {+-} 0.10) x 10{sup -6}, where the first error is statistical and the second is systematic. They do not observe a statistically significant signal in the latter channel and set an upper limit at {Beta}(B{sup 0} {yields} {omega}{gamma}) < 0.9 x 10{sup -6} (90% C.L.). They also measure the isospin and SU(3){sub F} violating quantities {Lambda}(B{sup +} {yields} {rho}{sup +}{gamma})/2{Lambda}(B{sup 0} {yields} {rho}{sup 0}{gamma})-1 = -0.43{sub -0.22}{sup +0.25} {+-} 0.10 and {Lambda}(B{sup 0} {yields} {omega}{gamma})/{Lambda}(B{sup 0} {yields} {rho}{sup …

The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory is exploring the physical limits of compression and focusing of ion beams for heating material to warm dense matter (WDM) and fusion ignition conditions. The NDCX is a beam transport experiment with several components at a scale comparable to an inertial fusion energy driver. The NDCX is an accelerator which consists of a low-emittance ion source, high-current injector, solenoid matching section, induction bunching module, beam neutralization section, and final focusing system. The principal objectives of the experiment are to control the beam envelope, demonstrate effective neutralization of the beam space-charge, control the velocity tilt on the beam, and understand defocusing effects, field imperfections, and limitations on peak intensity such as emittance and aberrations. Target heating experiments with space-charge dominated ion beams require simultaneous longitudinal bunching and transverse focusing. A four-solenoid lattice is used to tune the beam envelope to the necessary focusing conditions before entering the induction bunching module. The induction bunching module provides a head-to-tail velocity ramp necessary to achieve peak axial compression at the desired focal plane. Downstream of the induction gap a plasma column neutralizes the beam space charge so only emittance limits the focused beam …

A detailed study was done of the neomycin-B RNA aptamer for determining its selectivity and binding ability to both neomycin– and kanamycin-class aminoglycosides. A novel method to increase drug concentrations in cells for more efficiently killing is described. To test the method, a bacterial model system was adopted and several small RNA molecules interacting with aminoglycosides were cloned downstream of T7 RNA polymerase promoter in an expression vector. Then, the growth analysis of E. coli expressing aptamers was observed for 12-hour period. Our analysis indicated that aptamers helped to increase the intracellular concentration of aminoglycosides thereby increasing their efficacy.

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The goal of this work is to investigate methods in which anisotropy could be induced in fine-grained alloys. We have identified two general processing routes to creating a fine, textured microstructure: form an amorphous precursor and devitrify in a manner that induces texture or form the fine, textured microstructure upon cooling directly from the liquid state. Since it is possible to form significant amounts of amorphous material in RE-Fe-B alloys, texture could be induced through biasing the orientationof the crystallites upon crystallization of the amorphous material. One method of creating this bias is to form glassy material and apply uniaxial pressure during crystallization. Experiments on this are presented. All of the work presented here utilizes melt-spinning, either to create precursor material, or to achieve a desired final microstructure. To obtain greater control of the system to process these materials, a study was done on the effects of heating the wheel and modifying the wheel’s surface finish on glass formation and phase selection. The second general approach—creating the desired microstructure directly from the liquid—can be done through directional rapid solidification. In particular, alloys melt-spun at low tangential wheel speeds often display directional columnar growth through a portion of the ribbon. By …

High-pressure, high-temperature scanning tunneling microscopy (HPHTSTM) was used to study adsorbate structures and reactions on single crystal model catalytic systems. Studies of the automobile catalytic converter reaction [CO + NO {yields} 1/2 N{sub 2} + CO{sub 2}] on Rh(111) and ethylene hydrogenation [C{sub 2}H{sub 4} + H{sub 2} {yields} C{sub 2}H{sub 6}] on Rh(111) and Pt(111) elucidated information on adsorbate structures in equilibrium with high-pressure gas and the relationship of atomic and molecular mobility to chemistry. STM studies of NO on Rh(111) showed that adsorbed NO forms two high-pressure structures, with the phase transformation from the (2 x 2) structure to the (3 x 3) structure occurring at 0.03 Torr. The (3 x 3) structure only exists when the surface is in equilibrium with the gas phase. The heat of adsorption of this new structure was determined by measuring the pressures and temperatures at which both (2 x 2) and (3 x 3) structures coexisted. The energy barrier between the two structures was calculated by observing the time necessary for the phase transformation to take place. High-pressure STM studies of the coadsorption of CO and NO on Rh(111) showed that CO and NO form a mixed (2 x 2) structure …

A study was made of the performance of an orifice plate pulse column which is essentially a spray column containing internal constrictions in the form of orifices. The chemical system studied was acetic acid-waterhexone, and the variables considered were pulse frequency, throughput, phase continuity, and direction of solute transfer. For comparison purposes, several runs were made with a conventional spray column. Curves are presented showing the effect of the column variables on the column efficiency (HTU). The trends observed are explained as being due principally to the competing effects of the area for mass transfer and back-mixing. Photographs of a typical column section show qualitatively the effect of the important column variables. (auth)

The reaction of dispersed Uo/sub 2/ in an aluminum matrix in pressed compacts and fuel plates was studied at 500 to 600 deg C. Correlation of reaction with the accompanying volume increases was rmde and a growth mechanism proposed. Reaction rates and preducts are given as functions of UO/sub 2/ concentration temperature, and time. (W.D.M.)

We studied the effects on structural and magnetic phase transitions and the emergence of superconductivity in transition metal substituted BaFe{sub 2}As{sub 2}. We grew four series of Ba(Fe{sub 1-x}TM{sub x}){sub 2}As{sub 2} (TM=Ru, Mn, Co+Cr and Co+Mn) and characterized them by crystallographic, magnetic and transport measurements. We also subjected Ba(Fe{sub 1-x}Cr{sub x}){sub 2}As{sub 2} and Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} to heat treatment to explore what changes might be induced.

Many of the monitor wells that penetrate the upper portion of the Snake River Plain aquifer at the Idaho National Engineering Laboratory (INEL) are open over large intervals that include multiple water-bearing zones. Most of these wells are equipped with dedicated submersible pumps. Water of varying quality from different water-bearing zones is mixed within the wells. The hydrologic properties of individual water bearing zones are difficult to determine. Water quality and water-level data on organic, heavy metal, and radioactive contaminants have been collected, reported, and interpreted from these monitor wells for more than forty years. The problems associated with well completions over large intervals through multiple water-bearing zones raise significant questions about the data. A straddle-packer system was developed and applied at the INEL site to investigate the monitor well network. The straddle-packer system, hydraulic testing methods, data analysis procedures, and testing results are described in this report. The straddle-packer system and the straddle-packer testing and data evaluation procedures can be improved for future testing at the INEL site. Recommended improvements to the straddle-packer system are: (1) improved transducer pressure sensing systems, (2) faster opening riser valve, and (3) an in-line flowmeter in the riser pipe. Testing and data evaluation …

The mechanisms by which transparent dielectrics damage when exposed to high power laser radiation has been of scientific and technological interest since the invention of the laser. In this work, a set of three experiments are presented which provide insight into the damage initiation mechanisms and the processes involved in laser-induced damage. Using an OPO (optical parametric oscillator) laser, we have measured the damage thresholds of deuterated potassium dihydrogen phosphate (DKDP) from the near ultraviolet into the visible. Distinct steps, whose width is of order K{sub b}T, are observed in the damage threshold at photon energies associated with the number of photons (3{yields}2 or 4{yields}3) needed to promote a ground state electron across the energy gap. The wavelength dependence of the damage threshold suggests that a primary mechanism for damage initiation in DKDP is a multi-photon process in which the order is reduced through excited defect state absorption. In-situ fluorescence microscopy, in conjunction with theoretical calculations by Liu et al., has been used to establish that hydrogen displacement defects are potentially responsible for the reduction in the multi-photon cross-section. During the damage process, the material absorbs energy from the laser pulse and produces an ionized region that gives rise to …

After extensive investigations over three decades, the linear-coupling model and its equivalents have become the standard microscopic models for quantum harmonic Brownian motion, in which a harmonically bound Brownian particle is coupled to a quantum dissipative heat bath of general type modeled by infinitely many harmonic oscillators. The dynamics of these models have been studied by many authors using the quantum Langevin equation, the path-integral approach, quasi-probability distribution functions (e.g., the Wigner function), etc. However, the quantum Langevin equation is only applicable to some special problems, while other approaches all involve complicated calculations due to the inevitable reduction (i.e., contraction) operation for ignoring/eliminating the degrees of freedom of the heat bath. In this dissertation, the author proposes an improved methodology via a modified phase-space approach which employs the characteristic function (the symplectic Fourier transform of the Wigner function) as the representative of the density operator. This representative is claimed to be the most natural one for performing the reduction, not only because of its simplicity but also because of its manifestation of geometric meaning. Accordingly, it is particularly convenient for studying the time evolution of the Brownian particle with an arbitrary initial state. The power of this characteristic function is …

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Fission prcduct cross sections were measured radiochemically and mass- spectrometrically for gold bombsrded with 112-Mev C/sup 12/ ions. Cross sections for 43 nuclides were measured for elements from nickel to barium. Thirty-six yields are either primary fission product yields (independent yields) or were corrected (with less than 25% correction) so as to represent independent yields. The independent yields were empirically systematized and a yield-mass curve was constructed. The yield-mass curve is compared with the yield-mass curves obtained from the fission of Bi with 22 and 190-Mev deuterons. The yield systematics indicate that the sum of the mass numbers of complementary fission products is 13 plus or minus 1 amu less tban that of the compound nucleus, and the sum of the charges of complemertary fission products is two units less than that of the compound nucleus. It is postulated that 9 plus or minus 1 neutrons and an alpha particle must have been emitted. Evidence is presented that at least three and possibly more of the neutrons are emitted prior to fission. The most probable charge of the fission products as a function of mass number was determined empirically. It is shown that from mass number 80 to mass number …

The observation of gamma rays associated with the decay of {sup 26}Al and {sup 60}Fe can provide important information regarding ongoing nucleosynthesis in our galaxy. The half-lives of these radioisotopes (7.2 x 10{sup 5} y and 1.5 x 10{sup 6} y, respectively) are long compared to the interval between synthesis events such as supernovae, so they build up in a steady state in the interstellar medium (centered on the galactic plane, where massive stars reside), yet short enough that gamma radiation from their decay may be detected. Additionally, these half-lifes are short compared to the period of galactic revolution, so that observable abundances remain in the proximity of their production sites. Predicted abundances of {sup 26}Al and {sup 60}Fe vary widely between several calculations in the last decade. In 2004, the first observation of the gamma ray flux from {sup 60}Fe decay was reported, with a {sup 60}Fe/{sup 26}Al flux ratio in good agreement with nucleosynthesis modeling from 1995. However, recent calculations that include well motivated updates to the stellar and nuclear physics, predict a flux ratio as much as six times higher than the observed value. It is desirable to understand the discrepancy between the latest calculation, which in …

Single Particle Aerosol Mass Spectrometry (SPAMS) was evaluated as a real-time detection technique for single particles of high explosives. Dual-polarity time-of-flight mass spectra were obtained for samples of 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitro-1,3,5-triazinane (RDX), and pentaerythritol tetranitrate (PETN); peaks indicative of each compound were identified. Composite explosives, Comp B, Semtex 1A, and Semtex 1H were also analyzed, and peaks due to the explosive components of each sample were present in each spectrum. Mass spectral variability with laser fluence is discussed. The ability of the SPAMS system to identify explosive components in a single complex explosive particle ({approx}1 pg) without the need for consumables is demonstrated. SPAMS was also applied to the detection of Chemical Warfare Agent (CWA) simulants in the liquid and vapor phases. Liquid simulants for sarin, cyclosarin, tabun, and VX were analyzed; peaks indicative of each simulant were identified. Vapor phase CWA simulants were adsorbed onto alumina, silica, Zeolite, activated carbon, and metal powders which were directly analyzed using SPAMS. The use of metal powders as adsorbent materials was especially useful in the analysis of triethyl phosphate (TEP), a VX stimulant, which was undetectable using SPAMS in the liquid phase. The capability of SPAMS to detect high explosives and CWA …

Thesis written by a student in the UNT Honors College discussing the rise of Spanish, English, and French colonialism in the Americas, the conflicts that arose with the native populations, and alliances between the colonists and various tribes.

This paper describes methods for solid phase extraction and high performance liquid chromatography (HPLC). The following are described: Effects of Resin Sulfonation on the Retention of Polar Organic Compounds in Solid Phase Extraction; Ion-Chromatographic Separation of Alkali Metals In Non-Aqueous Solvents; Cation-Exchange Chromatography in Non-Aqueous Solvents; and Silicalite As a Stationary Phase For HPLC.

This report consists of five studies as follows: A laser photofragmentation time-of-flight mass spectrometric study of acetophenone at 193 and 248 nm; A 193 nm laser photofragmentation time-of-flight mass spectrometric study of dimethylsulfoxide; 193 nm laser photofragmentation time-of-flight mass spectrometric study of HSCH{sub 2}CH{sub 2}SH; Thiophene biradical decay of the primary laser photofragmentation product at 193 nm; and Scattering cross sections for O({sup 3}P)[SO(X,{sup 3}{Sigma}{sup {minus}})] + He[Ne, Ar, Kr]. Chapters are included for the introduction and general conclusions.

Investigations into the preparation of tungsten nitrides have involved the synthesis of molecular precursors, and their conversion to tungsten nitrides at relatively low temperatures. Two interesting molecular precursors, [WNCl{sub 3}{center_dot}NCCH{sub 3}]{sub 4} and WN(N{sub 3}){sub 3}{center_dot}xNCCH{sub 3}, have been prepared and characterized. The molecular structure of the first consists of a W{sub 4}N{sub 4} tetrameric core with multiple and single W-N bonds arranged in an alternating fashion. Three new solid state phases, amorphous W{sub 3}N{sub 5}, cubic WN, and W{sub 2}N{sub 2}(C{sub 2}N{sub 2}), have been discovered by solid state and chemical vapor transport reactions. The structures have been investigated. A systematic study in the Ln{sub 2}O{sub 3}-MoO{sub 3}-Mo (Ln = La, Ce, Pr, Nd, Sm) system has been explored to better understand LnMo{sub 8}O{sub 14}. The study has shown that the sizes of the rare-earth cations affect the formation of these phases. Larger cations (La, Ce, and Pr) aid in the formation of trans-Mo{sub 8} bicapped octahedra, and the smaller cations (Nd, Sm) only stabilize the cis-Mo{sub 8} bicapped octahedra. Magnetic susceptibility measurements have indicated that no effective moment contribution arises from the Mo{sub 8} metal clusters, even though the cis-Mo{sub 8} cluster in LnMo{sub 8}O{sub 14}, containing all …

The first chapter gives a brief overview of the system discussed in this dissertation. Chapters 2--5 and Appendix B of this dissertation consist of papers that are published, or have been submitted, which show experimental data regarding the phonon softening of LuNi{sub 2}B{sub 2}C. These papers have been removed and processed separately. Chapter 6 will contain a summary of the conclusions up to date. Appendix A will consist of a brief derivation of {chi}(q) which is talked about in the introduction of the dissertation. Appendix B will contain a Born-von Karman model fit to the experimental LuNi{sub 2}B{sub 2}C data and a comparison with experimental data. Appendix C will contain a brief summary of the work done on LuNi{sub 2}B{sub 2}C as well as a complete listing of experimental data taken on the crystals which may be needed later for theoretical models of this system. Appendix D will outline a brief introduction covering some of the field theory used in the theoretical work for this thesis.

The goal of this work is to explore several new strategies and approaches to the surface modification and the microscopic characterization of interfaces in the areas mainly targeting sensor technologies that are of interest to environmental control or monitoring, and scanning probe microscopies techniques that can monitor interfacial chemical reactions in real time. Centered on the main theme, four specific topics are presented as four chapters in this dissertation following the general introduction. Chapter 1 describes the development of two immobilization schemes for covalently immobilizing fluoresceinamine at cellulose acetate and its application as a pH sensing film. Chapter 2 investigates the applicability of SFM to following the base-hydrolysis of a dithio-bis(succinimidylundecanoate) monolayer at gold in situ. Chapter 3 studies the mechanism for the accelerated rate of hydrolysis of the dithio-bis(succinimidylundecanoate) monolayer at Au(111) surface. Chapter 4 focuses on the development of an electrochemical approach to the elimination of chloride interference in Chemical Oxygen Demand (COD) analysis of waste water. The procedures, results and conclusions are described in each chapter. This report contains the introduction, references, and general conclusions. Chapters have been processed separately for inclusion on the data base. 95 refs.

Quantum groups in general and the quantum Anti-de Sitter group U{sub q}(so(2,3)) in particular are studied from the point of view of quantum field theory. The author shows that if q is a suitable root of unity, there exist finite-dimensional, unitary representations corresponding to essentially all the classical one-particle representations with (half) integer spin, with the same structure at low energies as in the classical case. In the massless case for spin {ge} 1, {open_quotes}naive{close_quotes} representations are unitarizable only after factoring out a subspace of {open_quotes}pure gauges{close_quotes}, as classically. Unitary many-particle representations are defined, with the correct classical limit. Furthermore, the author identifies a remarkable element Q in the center of U{sub q}(g), which plays the role of a BRST operator in the case of U{sub q}(so(2,3)) at roots of unity, for any spin {ge} 1. The associated ghosts are an intrinsic part of the indecomposable representations. The author shows how to define an involution on algebras of creation and anihilation operators at roots of unity, in an example corresponding to non-identical particles. It is shown how nonabelian gauge fields appear naturally in this framework, without having to define connections on fiber bundles. Integration on Quantum Euclidean space and sphere …

Iron-aluminum alloys have been extensively evaluated as semi-continuous product such as sheet and bar, but have not been evaluated by net shape P/M processing techniques such as metal injection molding. The alloy compositions of iron-aluminum alloys have been optimized for room temperature ductility, but have limited high temperature strength. Hot extruded powder alloys in the Fe-Al-Si system have developed impressive mechanical properties, but the effects of sintering on mechanical properties have not been explored. This investigation evaluated three powder processed Fe-Al-Si alloys: Fe-15Al, Fe-15Al-2.8Si, Fe-15Al-5Si (atomic %). The powder alloys were produced with a high pressure gas atomization (HPGA) process to obtain a high fraction of metal injection molding (MIM) quality powder (D{sub 84} < 32 {micro}m). The powders were consolidated either by P/M hot extrusion or by vacuum sintering. The extruded materials were near full density with grain sizes ranging from 30 to 50 {micro}m. The vacuum sintering conditions produced samples with density ranging from 87% to 99% of theoretical density, with an average grain size ranging from 26 {micro}m to 104 {micro}m. Mechanical property testing was conducted on both extruded and sintered material using a small punch test. Tensile tests were conducted on extruded bar for comparison with …