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Radiological design criteria for fusion power test facilities

Description: The quest for fusion power and understanding of plasma physics has resulted in planning, design, and construction of several major fusion power test facilities, based largely on magnetic and inertial confinement concepts. We have considered radiological design aspects of the Joint European Torus (JET), Livermore Mirror and Inertial Fusion projects, and Princeton Tokamak. Our analyses on radiological design criteria cover acceptable exposure levels at the site boundary, man-rem doses for plant p… more
Date: February 12, 1982
Creator: Singh, M.S. & Campbell, G.W.
Partner: UNT Libraries Government Documents Department
open access

Toward Production From Gas Hydrates: Current Status, Assessment of Resources, and Simulation-Based Evaluationof Technology and Potential

Description: Gas hydrates are a vast energy resource with global distribution in the permafrost and in the oceans. Even if conservative estimates are considered and only a small fraction is recoverable, the sheer size of the resource is so large that it demands evaluation as a potential energy source. In this review paper, we discuss the distribution of natural gas hydrate accumulations, the status of the primary international R&D programs, and the remaining science and technological challenges facing c… more
Date: February 12, 2008
Creator: Reagan, Matthew; Moridis, George J.; Collett, Timothy; Boswell, Ray; Kurihara, M.; Reagan, Matthew T. et al.
Partner: UNT Libraries Government Documents Department
open access

Surprising Coordination Geometry Differences in Ce(IV)- and Pu(IV)-Maltol Complexes

Description: As part of a study to characterize the detailed coordination behavior of Pu(IV), single crystal X-ray diffraction structures have been determined for Pu(IV) and Ce(IV) complexes with the naturally-occurring ligand maltol (3-hydroxy-2-methyl-pyran-4-one) and its derivative bromomaltol (5-bromo-3-hydroxy-2-methyl-pyran-4-one). Although Ce(IV) is generally accepted as a structural analog for Pu(IV), and the maltol complexes of these two metals are isostructural, the corresponding bromomaltol compl… more
Date: February 12, 2008
Creator: Laboratory, Lawrence Berkeley National; Raymond, Kenneth; Szigethy, Geza; Xu, Jide; Gorden, Anne E.V.; Teat, Simon J. et al.
Partner: UNT Libraries Government Documents Department
open access

Measurement of Time-Dependent CP Asymmetry in B0->ccbar K(*)0 Decays

Description: The authors present updated measurements of time-dependent Cp asymmetries in fully reconstructed neutral B decays containing a charmonium meson. The measurements reported here use a data sample of (465 {+-} 5) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} storage rings operating at the SLAC National Accelerator Laboratory. The time-dependent CP asymmetry parameters measured from J/{psi} K{sub S}{sup 0}, J/{p… more
Date: February 12, 2009
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department
open access

Quantum Calisthenics: Gaussians, The Path Integral and Guided Numerical Approximations

Description: It is apparent to anyone who thinks about it that, to a large degree, the basic concepts of Newtonian physics are quite intuitive, but quantum mechanics is not. My purpose in this talk is to introduce you to a new, much more intuitive way to understand how quantum mechanics works. I begin with an incredibly easy way to derive the time evolution of a Gaussian wave-packet for the case free and harmonic motion without any need to know the eigenstates of the Hamiltonian. This discussion is complete… more
Date: February 12, 2009
Creator: Weinstein, Marvin
Partner: UNT Libraries Government Documents Department
open access

New inflation vs. chaotic inflation, higher degree potentials and the reconstruction program in light of WMAP3

Description: The cosmic microwave background power spectra are studied for different families of single field new and chaotic inflation models in the effective field theory approach to inflation. We implement a systematic expansion in 1/N(e), where N(e)~;;50 is the number of e-folds before the end of inflation. We study the dependence of the observables (n(s), r and dn(s)/dlnk) on the degree of the potential (2n) and confront them to the WMAP3 and large scale structure data: This shows in general that fourt… more
Date: February 12, 2007
Creator: Ho, Chiu Man; Boyanovsky, D.; de Vega, H.J.; Ho, C.M. & Sanchez, N.G.
Partner: UNT Libraries Government Documents Department
open access

Circumnuclear Star Clusters in the Galaxy Merger NGC 6240, Observed with Keck Adaptive Optics and HST

Description: We discuss images of the central {approx} 10 kpc (in projection) of the galaxy merger NGC 6240 at H and K{prime} bands, taken with the NIRC2 narrow camera on Keck II using natural guide star adaptive optics. We detect 28 star clusters in the NIRC2 images, of which only 7 can be seen in the similar-spatial-resolution, archival WFPC2 Planetary Camera data at either B or I bands. Combining the NIRC2 narrow camera pointings with wider NICMOS NIC2 images taken with the F110W, F160W, and F222M filter… more
Date: February 12, 2007
Creator: Pollack, L K; Max, C E & Schneider, G
Partner: UNT Libraries Government Documents Department
open access

Conversion of Parameters Among Variants of Scatchard's Neutral-Electrolyte Model for Electrolyte Mixtures that Have Different Numbers of Mixing Terms

Description: Various model equations are available for representing the excess Gibbs energy properties (osmotic and activity coefficients) of aqueous and other liquid mixed-electrolyte solutions. Scatchard's neutral-electrolyte model is among the simplest of these equations for ternary systems and contains terms that represent both symmetrical and asymmetric deviations from ideal mixing behavior when two single-electrolyte solutions are mixed in different proportions at constant ionic strengths. The usual f… more
Date: February 12, 2008
Creator: Rard, J. A. & Wijesinghe, A. M.
Partner: UNT Libraries Government Documents Department
open access

Measurements of time-dependent CP asymmetries in B0 --> D(*)+D(*)- decays

Description: We present new measurements of time-dependent CP asymmetries for B{sup 0} {yields} D{sup (*)+}d{sup (*)-} decays using (467 {+-} 5) x 10{sup 6} B{bar B} pairs collected with the BABAR detector located at the PEP-II B Factory at the Stanford Linear Accelerator Center. We determine the CP-odd fraction of the B{sup 0} {yields} D*{sup +}D*{sup -} decays to be R{perpendicular} = 0.158 {+-} 0.028 {+-} 0.006 and find CP asymmetry parameters for the CP-even component of the decay S{sub +} = -0.76 {+-} … more
Date: February 12, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Ternary Isothermal Diffusion Coefficients of NaCl-MgCl2-H2O at 25 C. 7. Seawater Composition

Description: The four diffusion coefficients D{sub ij} of the ternary system NaCl-MgCl{sub 2}-H{sub 2}O at the simplified seawater composition 0.48877 mol {center_dot} dm{sup -3} NaCl and 0.05110 mol {center_dot} dm{sup -3} MgCl{sub 2} have been remeasured at 25 C. The diffusion coefficients were obtained using both Gouy and Rayleigh interferometry with the highly precise Gosting diffusiometer. The results, which should be identical in principle, are essentially the same within or very close to their combin… more
Date: February 12, 2007
Creator: Miller, D. G.; Lee, C. M. & Rard, J. A.
Partner: UNT Libraries Government Documents Department
open access

Statistical analyses in the study of solar wind-magnetosphere coupling

Description: Statistical analyses provide a valuable method for establishing initially the existence (or lack of existence) of a relationship between diverse data sets. Statistical methods also allow one to make quantitative assessments of the strengths of observed relationships. This paper reviews the essential techniques and underlying statistical bases for the use of correlative methods in solar wind-magnetosphere coupling studies. Techniques of visual correlation and time-lagged linear cross-correlation… more
Date: February 12, 1985
Creator: Baker, D.N.
Partner: UNT Libraries Government Documents Department
open access

Cryopumping hydrogen isotope mixtures in MFTF-B with and without argon adsorbent

Description: Mixtures of hydrogen isotopes, primarily deuterium (D/sub 2/), protium-deuterium (HD), and protium (H/sub 2/) must be pumped by the vacuum system in the Mirror Fusion Test Facility at Lawrence Livermore National Laboratory. In this study, we used argon as an adsorbent for cryopumping these isotopes at 4.2 K and found that deuterium will displace already adsorbed protium. Thus, when we pump mixtures of the two, sufficient argon must be supplied to adsorb both species. We also found that without … more
Date: February 12, 1985
Creator: Schumacher, B.J. & Call, W.R.
Partner: UNT Libraries Government Documents Department
open access

Vision Denton '94

Description: Clippings from the Denton Record-Chronicle titled 'Vision Denton '94, City builds on education reputation'. The two clippings are part of the same story covering the collaboration of colleges including UNT, museums, and DFW Metroplex area schools. The collaboration offers better art programs and college credit to high schoolers.
Date: February 12, 1994
Creator: Cobler, Paula
Partner: UNT Libraries Special Collections
open access

Magnetic stochasticity in gyrokinetic simulations of plasma microturbulence

Description: Analysis of the magnetic field structure from electromagnetic simulations of tokamak ion temperature gradient turbulence demonstrates that the magnetic field can be stochastic even at very low plasma pressure. The degree of magnetic stochasticity is quantified by evaluating the magnetic diffusion coefficient. We find that the magnetic stochasticity fails to produce a dramatic increase in the electron heat conductivity because the magnetic diffusion coefficient remains small.
Date: February 12, 2010
Creator: Nevins, W M; Wang, E & Candy, J
Partner: UNT Libraries Government Documents Department
open access

Aspen Winter Conferences on High Energy

Description: The 2011 Aspen Winter Conference on Particle Physics was held at the Aspen Center for Physics from February 12 to February 18, 2011. Ninety-four participants from ten countries, and several universities and national labs attended the workshop titled, �New Data From the Energy Frontier.� There were 54 formal talks, and a considerable number of informal discussions held during the week. The week�s events included a public lecture (�The Hunt for the Elusive Higgs Boson� given by Ben Kilminster fro… more
Date: February 12, 2011
Creator: multiple speakers, presenters listed on link below
Partner: UNT Libraries Government Documents Department
open access

Extension of the Southern Hemisphere Atmospheric Radiocarbon Curve, 2120-850 years BP: Results from Tasmanian Huon Pine

Description: Decadal samples of dendrochronologically-dated pine (Lagorostrobos franklinii) from the Stanley River basin, Tasmania have been radiocarbon dated between 2120-850 yr BP. This data set overlaps and extends the current Southern Hemisphere record, which currently covers the period 110-995 yr BP. There is good agreement between the two records between 995-850 yr BP, between sample replicates and with consensus values for standards. As in the younger dataset, we find evidence for a distinct but vari… more
Date: February 12, 2010
Creator: Zimmerman, S. R.; Guilderson, T. P.; Buckley, B. M. & Cook, E.
Partner: UNT Libraries Government Documents Department
open access

INNOVATIVE ALARA TOOLS AND WORK PRACTICES USED AT THE DOE HANFORD SITE

Description: The Hanford Nuclear Reservation occupies an area of 586 square miles in southeastern Washington state. The site was created as part of the World War II Manhattan Project to produce weapons grade plutonium. A multitude of old reactor plants, processing facilities, underground tank farms, contaminated soil and ground water remain and are part of an on-going environmental cleanup mission of the site. The Columbia River bisects Hanford, and the concern is that the river will become contaminated if … more
Date: February 12, 2010
Creator: LO, WAGGONER
Partner: UNT Libraries Government Documents Department
open access

The Airborne Metagenome in an Indoor Urban Environment

Description: The indoor atmosphere is an ecological unit that impacts on public health. To investigate the composition of organisms in this space, we applied culture-independent approaches to microbes harvested from the air of two densely populated urban buildings, from which we analyzed 80 megabases genomic DNA sequence and 6000 16S rDNA clones. The air microbiota is primarily bacteria, including potential opportunistic pathogens commonly isolated from human-inhabited environments such as hospitals, but no… more
Date: February 12, 2008
Creator: Tringe, Susannah; Zhang, Tao; Liu, Xuguo; Yu, Yiting; Lee, Wah Heng; Yap, Jennifer et al.
Partner: UNT Libraries Government Documents Department
open access

Modelica-based Modeling and Simulation to Support Research and Development in Building Energy and Control Systems

Description: Traditional building simulation programs possess attributes that make them difficult to use for the design and analysis of building energy and control systems and for the support of model-based research and development of systems that may not already be implemented in these programs. This article presents characteristic features of such applications, and it shows how equation-based object-oriented modelling can meet requirements that arise in such applications. Next, the implementation of an op… more
Date: February 12, 2009
Creator: Wetter, Michael
Partner: UNT Libraries Government Documents Department
open access

Colloidally Synthesized Monodisperse Rh Nanoparticles Supported on SBA-15 for Size- and Pretreatment-Dependent Studies of CO Oxidation

Description: A particle size dependence for CO oxidation over rhodium nanoparticles of 1.9-11.3 nm has been investigated and determined to be modified by the existence of the capping agent poly(vinylpyrrolidone) (PVP). The particles were prepared using a polyol reduction procedure with PVP as the capping agent. The Rh nanoparticles were subsequently supported on SBA-15 during hydrothermal synthesis to produce Rh/SBA-15 supported catalysts for size-dependent catalytic studies. CO oxidation by O{sub 2} at 40 … more
Date: February 12, 2009
Creator: Grass, Michael E.; Joo, Sang Hoon & Somorjai, Gabor A.
Partner: UNT Libraries Government Documents Department
open access

Recent Developments And Validations in Geant4 Hadronic Physics

Description: The Geant4 hadronic models cover the entire range of energies required by calorimeters in new and planned experiments. The extension and improvement of the elastic, cascade, parameterized and quark-gluon string models will be discussed. Such improvements include the extension to more particle types, a review and correction of cross sections, and a better treatment of energy and momentum conservation. Concurrent with this development has been a validation program which includes comparisons with … more
Date: February 12, 2007
Creator: Wright, D. H.; Koi, T.; Folger, G.; Ivanchenko, V.; Kossov, M.; Starkov, N. et al.
Partner: UNT Libraries Government Documents Department
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