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Diagnostics developments and applications for laser fusion experiments (open access)

Diagnostics developments and applications for laser fusion experiments

Some diagnostics techniques applied to current laser fusion target experiments are reviewed. Specifically, holographic interferometry of target plasmas, coded aperture imaging of thermonuclear alpha-particles and neutron energy spectrum measurements are discussed.
Date: September 2, 1977
Creator: Coleman, L.W.
System: The UNT Digital Library
Structure-based inference of molecular functions of proteins of unknown function from Berkeley Structural Genomics Center (open access)

Structure-based inference of molecular functions of proteins of unknown function from Berkeley Structural Genomics Center

Advances in sequence genomics have resulted in an accumulation of a huge number of protein sequences derived from genome sequences. However, the functions of a large portion of them cannot be inferred based on the current methods of sequence homology detection to proteins of known functions. Three-dimensional structure can have an important impact in providing inference of molecular function (physical and chemical function) of a protein of unknown function. Structural genomics centers worldwide have been determining many 3-D structures of the proteins of unknown functions, and possible molecular functions of them have been inferred based on their structures. Combined with bioinformatics and enzymatic assay tools, the successful acceleration of the process of protein structure determination through high throughput pipelines enables the rapid functional annotation of a large fraction of hypothetical proteins. We present a brief summary of the process we used at the Berkeley Structural Genomics Center to infer molecular functions of proteins of unknown function.
Date: September 2, 2007
Creator: Kim, Sung-Hou; Shin, Dong Hae; Hou, Jingtong; Chandonia, John-Marc; Das, Debanu; Choi, In-Geol et al.
System: The UNT Digital Library
IR Spectrometer Using 90-degree Off-axis Parabolic Mirrors (open access)

IR Spectrometer Using 90-degree Off-axis Parabolic Mirrors

A gated spectrometer has been designed for real-time, pulsed infrared (IR) studies at the National Synchrotron Light ource at the Brookhaven National Laboratory. A pair of 90-degree, off-axis parabolic mirrors are used to relay the light from an entrance slit to an output IR recording camera. With an initial wavelength range of 1500–4500 nm required, gratings could not be used in the spectrometer because grating orders would overlap. A magnesium oxide prism, placed between these parabolic mirrors, serves as the dispersion element. The spectrometer is doubly telecentric. With proper choice of the air spacing between the prism and the second parabolic mirror, any spectral region of interest within the InSb camera array’s sensitivity region can be recorded. The wavelengths leaving the second parabolic mirror are collimated, thereby relaxing the camera positioning tolerance. To set up the instrument, two different wavelength (visible) lasers are introduced at the entrance slit and made collinear with the optical axis via flip mirrors. After dispersion by the prism, these two laser beams are directed to tick marks located on the outside housing of the gated IR camera. This provides first-order wavelength calibration for the instrument. Light that is reflected off the front prism face is …
Date: September 2, 2008
Creator: Robert M. Malone, Richard, G. Hacking, Ian J. McKenna, and Daniel H. Dolan
System: The UNT Digital Library
Latest results from the SEMATECH Berkeley extreme ultraviolet microfield exposure tool (open access)

Latest results from the SEMATECH Berkeley extreme ultraviolet microfield exposure tool

Microfield exposure tools (METs) continue to play a dominant role in the development of extreme ultraviolet (EUV) resists. One of these tools is the 0.3 numerical aperture SEMATECH Berkeley MET operating as a resist and mask test center. Here they present an update on the tool summarizing some of the latest test and characterization results. they provide an update on the long-term aberration stability of the tool and present line-space imaging in chemically amplified photoresist down to the 20-nm half-pitch level. Although resist development has shown substantial progress in the area of resolution, line-edge-roughness (LER) remains a significant concern. Here we present a summary of recent LER performance results and consider the effect of mask contributors to the LER observed from the SEMATECH Berkeley microfield tool.
Date: September 2, 2008
Creator: Naulleau, Patrick; Anderson, Christopher N.; Chiu, Jerrin; Dean, Kim; Denham, Paul; George, Simi et al.
System: The UNT Digital Library
Estimates of energy fluence at the focal plane in beams undergoing neutralized drift compression (open access)

Estimates of energy fluence at the focal plane in beams undergoing neutralized drift compression

The authors estimate the energy fluence (energy per unit area) at the focal plane of a beam undergoing neutralized drift compression and neutralized solenoidal final focus, as is being carried out in the Neutralized Drift Compression Experiment (NDCX) at LBNL. In these experiments, in order to reach high beam intensity, the beam is compressed longitudinally by ramping the beam velocity (i.e. introducing a velocity tilt) over the course of the pulse, and the beam is transversely focused in a high field solenoid just before the target. To remove the effects of space charge, the beam drifts in a plasma. The tilt introduces chromatic aberrations, with different slices of the original beam having different radii at the focal plane. The fluence can be calculated by summing the contribution from the various slices. They develop analytic formulae for the energy fluence for beams that have current profiles that are initially constant in time. They compare with envelope and particle-in-cell calculations. The expressions derived are useful for predicting how the fluence scales with accelerator and beam parameters.
Date: September 2, 2008
Creator: Barnard, J. J.; Seidl, P. A.; Coleman, J. E.; Ogata, D. & Welch, D. R.
System: The UNT Digital Library
Multi-layered Spectral Formation in SNe Ia Around Maximum Light (open access)

Multi-layered Spectral Formation in SNe Ia Around Maximum Light

We use the radiative transfer code \phx\ to study the line formation of the wavelength region 5000-7000 Angstrom. This is the region where the SNe Ia defining Si II feature occurs. This region is important since the ratio of the two nearby silicon lines has been shown to correlate with the absolute blue magnitude. We use a grid of LTE synthetic spectral models to investigate the formation of line features in the spectra of SNe Ia. By isolating the main contributors to the spectral formation we show that the ions that drive the spectral ratio are FeIII, FeII, SiII and SII. While the first two strongly dominate the flux transfer, the latter two form in the same physical region inside of the supernova. We also show that the naive blackbody that one would derive from a fit to the observed spectrum is far different than the true underlying continuum.
Date: September 2, 2008
Creator: Bongard, Sebastien; Baron, E.; Smadja, G.; Branch, David & Hauschildt, Peter H.
System: The UNT Digital Library
Electron Cloud Cyclotron Resonances in the Presence of a Short-bunch-length Relativistic Beam (open access)

Electron Cloud Cyclotron Resonances in the Presence of a Short-bunch-length Relativistic Beam

Computer simulations using the 2D code"POSINST" were used to study the formation of the electron cloud in the wiggler section of the positron damping ring of the International Linear Collider. In order to simulate an x-y slice of the wiggler (i.e., a slice perpendicular to the beam velocity), each simulation assumed a constant vertical magnetic field. At values of the magnetic field where the cyclotron frequency was an integral multiple of the bunch frequency, and where the field strength was less than approximately 0.6 T, equilibrium average electron densities were up to three times the density found at other neighboring field values. Effects of this resonance between the bunch and cyclotron frequency are expected to be non-negligible when the beam bunch length is much less than the product of the electron cyclotron period and the beam velocity, for a beam moving at v~;;c. Details of the dynamics of the resonance are described.
Date: September 2, 2008
Creator: Celata, C. M.; Furman, Miguel A.; Vay, J. L. & Yu, Jennifer W.
System: The UNT Digital Library
Role of Exponential Type Random Invexities for Asymptotically Sufficient Efficiency Conditions in Semi-Infinite Multi-Objective Fractional Programming (open access)

Role of Exponential Type Random Invexities for Asymptotically Sufficient Efficiency Conditions in Semi-Infinite Multi-Objective Fractional Programming

This article introduces several notions of random exponential type asymptotic invexities to establish results to the context of a class of asymptotically sufficient efficiency conditions in semi-infinite multi-objective fractional programing.
Date: September 2, 2016
Creator: Verma, Ram U. & Seol, Youngsoo
System: The UNT Digital Library
Methodological and Practical Considerations for DevelopingMultiproject Baselines for Electric Power and Cement Industry Projects inCentral America (open access)

Methodological and Practical Considerations for DevelopingMultiproject Baselines for Electric Power and Cement Industry Projects inCentral America

The Lawrence Berkeley National Laboratory (Berkeley Lab) andthe Center for Sustainable Development in the Americas (CSDA) conductedtechnical studies and organized two training workshops to developcapacity in Central America for the evaluation of climate changeprojects. This paper describes the results of two baseline case studiesconducted for these workshops, one for the power sector and one for thecement industry, that were devised to illustrate certain approaches tobaseline setting. Multiproject baseline emission rates (BERs) for themain Guatemalan electricity grid were calculated from 2001 data. Inrecent years, the Guatemalan power sector has experienced rapid growth;thus, a sufficient number of new plants have been built to estimateviable BERs. We found that BERs for baseload plants offsetting additionalbaseload capacity ranged from 0.702 kgCO2/kWh (using a weighted averagestringency) to 0.507 kgCO2/kWh (using a 10th percentile stringency),while the baseline for plants offsetting load-followingcapacity is lowerat 0.567 kgCO2/kWh. For power displaced from existing load-followingplants, the rate is higher, 0.735 kgCO2/kWh, as a result of the age ofsome plants used for meeting peak loads and the infrequency of their use.The approved consolidated methodology for the Clean Development Mechanismyields a single rate of 0.753 kgCO2/kWh. Due to the relatively smallnumber of cement plants in the region and the regional nature of …
Date: September 2, 2004
Creator: Murtishaw, Scott; Sathaye, Jayant; Galitsky, Christina & Dorion,Kristel
System: The UNT Digital Library
Wavelengths of the 3p-3d transitions of the Co- and Fe-like ions: The effects of electron correlation (open access)

Wavelengths of the 3p-3d transitions of the Co- and Fe-like ions: The effects of electron correlation

The experimental observations of the 3p/sup 6/ 3d/sup 9/ /sup 2/D - 3p/sup 5/ 3d/sup 10/ /sup 2/p transitions of the Co-like ions and 3p/sup 6/ 3d/sup 8/ /sup 3/F/sub 4/ - 3p/sup 5/ 3d/sup 9/ /sup 3/F/sub 3/ of the Fe-like ions have recently been extended to highly charged ions of heavy elements up to uranium (Z = 92). A comparison between the observed energies and calculated values from the Dirac-Fock model indicated persistent discrepancies of 3 to 4 eV for all ions. Systematic multiconfiguration Dirac-Fock calculations for these transitions have been carried out with emphases on the effects of electron correlation. The previously found discrepancies theory and experiment have mostly removed after the inclusion of the electron-electron correlation effects in the theoretical calculations. 13 refs.
Date: September 2, 1987
Creator: Chen, Mau Hsiung
System: The UNT Digital Library
TMX-U diagnostic system (open access)

TMX-U diagnostic system

Using data from the TMX-U diagnostic system, the production of sloshing ions has already been verified and the formation of electron thermal barriers is presently being investigated on the Tandem Mirror Experiment-Upgrade (TMX-U) at Lawrence Livermore National Laboratory. The TMX-U diagnostics are made up of the earlier TMX complement of diagnostics that determine confinement, microstability, and low-frequency stability, plus diagnostic instrumentation that measures electron parameters associated with mirror-confined electrons. This paper describes the three subsystems within the TMX-U diagnostic system: (1) the diagnostic facility (shot leader console, data cable system, and diagnostic timing system); (2) the individual diagnostic instruments that measure plasma and machine parameters; and (3) the data-acquisition and -analysis computer.
Date: September 2, 1983
Creator: Correll, D.L.
System: The UNT Digital Library
Debugging the virtual machine (open access)

Debugging the virtual machine

A computer program is really nothing more than a virtual machine built to perform a task. The program`s source code expresses abstract constructs using low level language features. When a virtual machine breaks, it can be very difficult to debug because typical debuggers provide only low level machine implementation in formation to the software engineer. We believe that the debugging task can be simplified by introducing aspects of the abstract design into the source code. We introduce OODIE, an object-oriented language extension that allows programmers to specify a virtual debugging environment which includes the design and abstract data types of the virtual machine.
Date: September 2, 1994
Creator: Miller, P. & Pizzi, R.
System: The UNT Digital Library
Atomic layer deposition of ZnO on ultra-low-density nanoporous silica aerogel monoliths (open access)

Atomic layer deposition of ZnO on ultra-low-density nanoporous silica aerogel monoliths

We report on atomic layer deposition of an {approx} 2-nm-thick ZnO layer on the inner surface of ultralow-density ({approx} 0.5% of the full density) nanoporous silica aerogel monoliths with an extremely large effective aspect ratio of {approx} 10{sup 5} (defined as the ratio of the monolith thickness to the average pore size). The resultant monoliths are formed by amorphous-SiO{sub 2}/wurtzite-ZnO nanoparticles which are randomly oriented and interconnected into an open-cell network with an apparent density of {approx} 3% and a surface area of {approx} 100 m{sup 2} g{sup -1}. Secondary ion mass spectrometry and high-resolution transmission electron microscopy imaging reveal excellent uniformity and crystallinity of ZnO coating. Oxygen K-edge and Zn L{sub 3}-edge soft x-ray absorption near-edge structure spectroscopy shows broadened O 2p- as well as Zn 4s-, 5s-, and 3d-projected densities of states in the conduction band.
Date: September 2, 2004
Creator: Kucheyev, S O; Biener, J; Wang, Y M; Baumann, T F; Wu, K J; van Buuren, T et al.
System: The UNT Digital Library
A Meta-Analysis of Energy Savings from Lighting Controls in Commercial Buildings (open access)

A Meta-Analysis of Energy Savings from Lighting Controls in Commercial Buildings

None
Date: September 2, 2011
Creator: Williams, Alison; Atkinson, Barbara; Garbesi, Karina; Rubinstein, Francis & Page, Erik
System: The UNT Digital Library
Biospecimen Reporting for Improved Study Quality (BRISQ) (open access)

Biospecimen Reporting for Improved Study Quality (BRISQ)

Human biospecimens are subjected to collection, processing, and storage that can significantly alter their molecular composition and consistency. These biospecimen preanalytical factors, in turn, influence experimental outcomes and the ability to reproduce scientific results. Currently, the extent and type of information specific to the biospecimen preanalytical conditions reported in scientific publications and regulatory submissions varies widely. To improve the quality of research that uses human tissues, it is crucial that information on the handling of biospecimens be reported in a thorough, accurate, and standardized manner. The Biospecimen Reporting for Improved Study Quality (BRISQ) recommendations outlined herein are intended to apply to any study in which human biospecimens are used. The purpose of reporting these details is to supply others, from researchers to regulators, with more consistent and standardized information to better evaluate, interpret, compare, and reproduce the experimental results. The BRISQ guidelines are proposed as an important and timely resource tool to strengthen communication and publications on biospecimen-related research and to help reassure patient contributors and the advocacy community that their contributions are valued and respected.
Date: September 2, 2010
Creator: Institute, National Cancer; Jewell, Ph.D., Scott D.; Seijo, M.S., Edward; Kelly, Ph.D., Andrea; Somiari, Ph.D., Stella; B.Chir., M.B. et al.
System: The UNT Digital Library
Challenge in Numerical Software for Microcomputers (open access)

Challenge in Numerical Software for Microcomputers

Microcomputers are now capable of serious numerical computation using programmed floating-point arithmetic and Basic compilers. Unless numerical software designers for these machines exploit experience gained in providing software for larger machines, history will repeat with the initial spread of treacherous software. This paper discusses good software, especially for the elementary functions, in terms of reliability and robustness. The emphasis. is on insight rather than detailed algorithms, to show why certain things are important and how they may be achieved.
Date: September 2, 1977
Creator: Cody, W J
System: The UNT Digital Library
[The Washington Blade: Two months later, Stonewall 25 still in red] (open access)

[The Washington Blade: Two months later, Stonewall 25 still in red]

A copy of an article from the Washington Blade newspaper summarizing the debt of both Stonewall 25 and the Gay Games IV accumulated from the banks and other businesses after the events.
Date: September 2, 1994
Creator: unknown
System: The UNT Digital Library
SUCCESSES AND EMERGING ISSUES IN SIMULATING THE PROCESSING BEHAVIOR OF LIQUID-PARTICLE NUCLEAR WASTE SLURRIES AT THE SAVANNAH RIVER SITE - 205E (open access)

SUCCESSES AND EMERGING ISSUES IN SIMULATING THE PROCESSING BEHAVIOR OF LIQUID-PARTICLE NUCLEAR WASTE SLURRIES AT THE SAVANNAH RIVER SITE - 205E

Slurries of inorganic solids, containing both stable and radioactive elements, were produced during the cold war as by-products of the production of plutonium and enriched uranium and stored in large tanks at the Savannah River Site. Some of this high level waste is being processed into a stable glass waste form today. Waste processing involves various large scale operations such as tank mixing, inter-tank transfers, washing, gravity settling and decanting, chemical adjustment, and vitrification. The rheological properties of waste slurries are of particular interest. Methods for modeling flow curve data and predicting the properties of slurry blends are particularly important during certain operational phases. Several methods have been evaluated to predict the rheological properties of sludge slurry blends from the data on the individual slurries. These have been relatively successful.
Date: September 2, 2009
Creator: Koopman, D.; Lambert, D. & Stone, M.
System: The UNT Digital Library
SUCCESSES AND EMERGING ISSUES IN SIMULATING THE MIXING BEHAVIOR OF LIQUID-PARTICLE NUCLEAR WASTE SLURRIES AT THE SAVANNAH RIVER SITE - 211B (open access)

SUCCESSES AND EMERGING ISSUES IN SIMULATING THE MIXING BEHAVIOR OF LIQUID-PARTICLE NUCLEAR WASTE SLURRIES AT THE SAVANNAH RIVER SITE - 211B

Aqueous radioactive high-level waste slurries are combined during processing steps that ultimately produce a stable borosilicate glass waste form. Chemically treated waste slurries are combined with each other and with glass frit-water slurries to produce the melter feed. Understanding the evolution of the rheological properties of the slurries is an important aspect of removing and treating the stored waste. To a first approximation, combinations of colloidal waste slurry with {approx}0.1-mm mean diameter glass frit or glass beads act in an analogous matter to slurries of spherical beads in Newtonian liquids. The non-Newtonian rheological properties of the waste slurries without frit, however, add complexity to the hydrodynamic analysis. The use of shear rate dependent apparent viscosities with the modified Einstein equation was used to model the rheological properties of aqueous frit-waste slurries.
Date: September 2, 2009
Creator: Koopman, D.; Pickenheim, B.; Lambert, D. & Stone, M.
System: The UNT Digital Library
CHARACTERIZATION OF INDIVIDUAL CHEMICAL REACTIONS CONSUMING ACID DURING NUCLEAR WASTE PROCESSING AT THE SAVANNAH RIVER SITE - 136B (open access)

CHARACTERIZATION OF INDIVIDUAL CHEMICAL REACTIONS CONSUMING ACID DURING NUCLEAR WASTE PROCESSING AT THE SAVANNAH RIVER SITE - 136B

Conversion of legacy radioactive high-level waste at the Savannah River Site into a stable glass waste form involves a chemical pretreatment process to prepare the waste for vitrification. Waste slurry is treated with nitric and formic acids to achieve certain goals. The total quantity of acid added to a batch of waste slurry is constrained by the catalytic activity of trace noble metal fission products in the waste that can convert formic acid into hydrogen gas at many hundreds of times the radiolytic hydrogen generation rate. A large block of experimental process simulations were performed to characterize the chemical reactions that consume acid prior to hydrogen generation. The analysis led to a new equation for predicting the quantity of acid required to process a given volume of waste slurry.
Date: September 2, 2009
Creator: Koopman, D.; Pickenheim, B.; Lambert, D.; Newell, J. & Stone, M.
System: The UNT Digital Library
Mercury-Nitrite-Rhodium-Ruthenium Interactions in Noble Metal Catalyzed Hydrogen Generation From Formic Acid During Nuclear Waste Processing at the Savannah River Site - 136c (open access)

Mercury-Nitrite-Rhodium-Ruthenium Interactions in Noble Metal Catalyzed Hydrogen Generation From Formic Acid During Nuclear Waste Processing at the Savannah River Site - 136c

Chemical pre-treatment of radioactive waste at the Savannah River Site is performed to prepare the waste for vitrification into a stable waste glass form. During pre-treatment, compounds in the waste become catalytically active. Mercury, rhodium, and palladium become active for nitrite destruction by formic acid, while rhodium and ruthenium become active for catalytic conversion of formic acid into hydrogen and carbon dioxide. Nitrite ion is present during the maximum activity of rhodium, but is consumed prior to the activation of ruthenium. Catalytic hydrogen generation during pre-treatment can exceed radiolytic hydrogen generation by several orders of magnitude. Palladium and mercury impact the maximum catalytic hydrogen generation rates of rhodium and ruthenium by altering the kinetics of nitrite ion decomposition. New data are presented that illustrate the interactions of these various species.
Date: September 2, 2009
Creator: Koopman, David C.; Pickenheim, Bradley R.; Lambert, Daniel P.; Newell, J. David & Stone, Michael E.
System: The UNT Digital Library
The effect of pi-stacking, h-bonding, and electrostatic interactions on the ionization energies of nucleic acid bases: adenine-adenine, thymine-thymine and adenine-thymine dimers (open access)

The effect of pi-stacking, h-bonding, and electrostatic interactions on the ionization energies of nucleic acid bases: adenine-adenine, thymine-thymine and adenine-thymine dimers

A combined theoretical and experimental study of the ionized dimers of thymine and adenine, TT, AA, and AT, is presented. Adiabatic and vertical ionization energies(IEs) for monomers and dimers as well as thresholds for the appearance of the protonated species are reported and analyzed. Non-covalent interactions stronglyaffect the observed IEs. The magnitude and the nature of the effect is different for different isomers of the dimers. The computations reveal that for TT, the largestchanges in vertical IEs (0.4 eV) occur in asymmetric h-bonded and symmetric pi- stacked isomers, whereas in the lowest-energy symmetric h-bonded dimer the shiftin IEs is much smaller (0.1 eV). The origin of the shift and the character of the ionized states is different in asymmetric h-bonded and symmetric stacked isomers. Inthe former, the initial hole is localized on one of the fragments, and the shift is due to the electrostatic stabilization of the positive charge of the ionized fragment by thedipole moment of the neutral fragment. In the latter, the hole is delocalized, and the change in IE is proportional to the overlap of the fragments' MOs. The shifts in AAare much smaller due to a less effcient overlap and a smaller dipole moment. The ionization …
Date: September 2, 2009
Creator: Bravaya, Ksenia B.; Kostko, Oleg; Ahmed, Musahid & Krylov, Anna I.
System: The UNT Digital Library
Assessment Context High-Level Overview of the WMA C Performance Assessment (open access)

Assessment Context High-Level Overview of the WMA C Performance Assessment

This report addresses the high-level overview of the WMA C performance assessment.
Date: September 2, 2009
Creator: Connelly, M. P.
System: The UNT Digital Library
The Reaction of bis(1,2,4-tri-t-butylcyclopentadienyl)ceriumbenzyl, Cp'2CeCH2Ph with Methylhalides: a Metathesis Reaction that does not proceed by a Metathesis Transition State (open access)

The Reaction of bis(1,2,4-tri-t-butylcyclopentadienyl)ceriumbenzyl, Cp'2CeCH2Ph with Methylhalides: a Metathesis Reaction that does not proceed by a Metathesis Transition State

The experimental reaction between [1,2,4-(Me3C)3C5H2]2CeCH2Ph and CH3X, X = F, Cl, Br, and I, yields the metathetical exchange products, [1,2,4-(Me3C)3C5H2]2CeX and CH3CH2Ph. The reaction is complicated by the equilibrium between the benzyl derivative and the metallacycle [[1,2,4-(Me3C)3C5H2] [(Me3C)2C5H2C(CH3)2CH2]Ce, plus toluene since the metallacycle reacts with CH3X. Labelling studies show that the methyl group of the methylhalide is transferred intact to the benzyl group. The mechanism, as revealed by DFT calculations on (C5H5)2CeCH2Ph and CH3F, does not proceed by way of a four-center mechanism, (sigma-bond metathesis) but a lower barrier process involves a haptotropic shift of the Cp2Ce fragment so that at the transition state the para-carbon of the benzene ring is attached to the Cp2Ce fragment while the CH2 fragment of the benzyl group attacks CH3F that is activated by coordination to the metal ion. As a result the mechanism is classified as an associative interchange process.
Date: September 2, 2009
Creator: Werkema, Evan; Andersen, Richard; Maron, Laurent & Eisenstein, Odile
System: The UNT Digital Library