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Observation of amplification of a 1ps pulse by SRS of a 1 ns pulse in a plasma with conditions relevant to pulse compression

Description: The compression of a laser pulse by amplification of an ultra short pulse beam Which seeds the stimulated Raman scatter of the first beam has been long been discussed in the context of solid and gas media. We investigate the possibility of using intersecting beams in a plasma to compress nanosecond pulses to picosecond duration by scattering from driven electron waves. Recent theoretical studies have shown the possibility of efficient compression With large amplitude, non-linear Langmuir waves … more
Date: May 24, 2006
Creator: Kirkwood, R K; Dewald, E; Wilks, S C; Meezan, N; Niemann, C; Berger, R L et al.
Partner: UNT Libraries Government Documents Department
open access

Mineral dissolution kinetics at the pore scale

Description: Mineral dissolution rates in the field have been reported to be orders of magnitude slower than those measured in the laboratory, an unresolved discrepancy that severely limits our ability to develop scientifically defensible predictive or even interpretive models for many geochemical processes in the earth and environmental sciences. One suggestion links this discrepancy to the role of physical and chemical heterogeneities typically found in subsurface soils and aquifers in producing scale-dep… more
Date: May 24, 2007
Creator: Li, L.; Steefel, C.I. & Yang, L.
Partner: UNT Libraries Government Documents Department
open access

High-Throughput Plasmid cDNA Library Screening

Description: Libraries of cDNA clones are valuable resources foranalysing the expression, structure, and regulation of genes, as well asfor studying protein functions and interactions. Full-length cDNA clonesprovide information about intron and exon structures, splice junctionsand 5'- and 3'-untranslated regions (UTRs). Open reading frames (ORFs)derived from cDNA clones can be used to generate constructs allowingexpression of native proteins and N- or C-terminally tagged proteins.Thus, obtaining full-length… more
Date: May 24, 2006
Creator: Wan, Kenneth H.; Yu, Charles; George, Reed A.; Carlson, JosephW.; Hoskins, Roger A.; Svirskas, Robert et al.
Partner: UNT Libraries Government Documents Department
open access

Properties of inclusive W, Z events in p p collisions at 1. 8 TeV

Description: A preliminary measurement of the properties of W and Z production along with accompanying jets has been made in {anti p}p collisions at 1.8 TeV using the CDF detector at Fermilab. Distributions of jet multiplicity, and boson E{sub T}, with and without selection on jet multiplicity, were obtained. Agreement was found with perturbative QCD predictions.
Date: May 24, 1990
Creator: Watts, T. (Rutgers--the State Univ., Piscataway, NJ (USA))
Partner: UNT Libraries Government Documents Department
open access

Solar energy conference, final report

Description: The conference attendance, publicity and press coverage, brochure mailing, presentations, displays, exhibitors, management seminar checklist, and seminar evaluation by attendees are presented. Also included are the proposal for funding of the conference, the list of attendees, keynote speeches, agenda, and feedback questionnaire. (MHR)
Date: May 24, 1977
Partner: UNT Libraries Government Documents Department
open access

Upgrade of MFTF-B for fusion technology

Description: This report discussses such things as operating scenarios and engineering features of the upgrade. In particular, such things as the magnet system, heating, fueling, drift pumping, halo scraper, direct converter, vacuum pumping, tritium systems, vacuum vessel and support structure, shielding, electrical systems, maintenance, safety and siting, and the operation and test program are described. (MOW)
Date: May 24, 1984
Creator: Thomassen, K. I.; Doggett, J. N.; Logan, B. G. & Nelson, W. D.
Partner: UNT Libraries Government Documents Department
open access

The other high resolution post accelerator approach

Description: There has been significant discussion in consideration of a high resolution mass separator followed by a RFQ and a linear accelerator as the basic format for IsoSpin Laboratory. There exists another strong possibility-namely a low-resolution mass separator coupled to a cyclotron. The major objection to this approach has been that the conversion from the +1 mass separator beam to a q/m beam of 1/4 to 1/3 is thought to be highly inefficient. Since we are in the fortunate position of having the tw… more
Date: May 24, 1993
Creator: Moltz, D. M.; Tighe, R. J.; Rowe, M. W.; Ognibene, T. J. & Cerny, J.
Partner: UNT Libraries Government Documents Department
open access

Simulation of Plasma Fluxes to Material Surfaces with Self-Consistent Edge Turbulence and Transport for Tokamaks

Description: The edge-plasma profiles and fluxes to the divertor and walls of a divertor tokamak with a magnetic X-point are simulated by coupling a 2D transport code (UEDGE) and a 3D turbulence code (BOUT). An relaxed iterative coupling scheme is used where each code is run on its characteristic time scale, resulting in a statistical steady state. Plasma variables of density, parallel velocity, and separate ion and electron temperatures are included, together with a fluid neutral model for recycling neutra… more
Date: May 24, 2004
Creator: Rognlien, T.; Umansky, M.; Xu, X.; Cohen, R. & LoDestro, L.
Partner: UNT Libraries Government Documents Department
open access

Comparison of Plasma Parameters Between QH and ELMing Phases of the Same Discharges

Description: H-mode confinement is observed for many energy confinement times without edge localized modes (ELMs) in QH (quiescent high-confinement)-mode discharges in DIII-D. To find critical differences between ELMing and QH modes we compared electron temperature (T{sub e}), density (n{sub e}), and ion temperature (T{sub i}), in the pedestal and scrape-off layer (SOL) for a group of discharges. We also compared the electron pressures P{sub ped}, and maximum pressure gradients P{sub e,ped,max grad} because… more
Date: May 24, 2004
Creator: Lasnier, C.; West, W.; Burrell, K.; deGrassie, J.; Doyle, E. & Osborne, T.
Partner: UNT Libraries Government Documents Department
open access

Determining Cross Sections for Reactions on Unstable Nuclei: A Consideration of Indirect Approaches

Description: An indirect method for determining cross sections for reactions proceeding through a compound nucleus is presented. The appropriate theoretical framework for applications of this method is reviewed and theoretical and experimental challenges that need to be addressed in applications of the method are outlined. Two approximations are considered and their advantages and limitations are discussed.
Date: May 24, 2005
Creator: Escher, J & Dietrich, F S
Partner: UNT Libraries Government Documents Department
open access

Identification of Rydberg states in the atomic lanthanides and actinides

Description: The study of Rydberg spectra and ionization thresholds of ten lanthanides using several variations of time-resolved resonant multistep techniques is reported. The ionization limits for the lanthanides determined in this way show a systematic dependence on atomic number. A physical model explaining these results is presented. 16 references. (JFP)
Date: May 24, 1977
Creator: Paisner, J. A.; Solarz, R. W.; Worden, E. F. & Conway, J. G.
Partner: UNT Libraries Government Documents Department
open access

Thermal decomposition and reaction of confined explosives. [TNT, TATB, LX-04, LX-10]

Description: Some new experiments designed to accurately determine the time interval required to produce a reactive event in confined explosives subjected to temperatures which will cause decomposition are described. Geometry and boundary conditions were both well defined so that these experiments on the rapid thermal decomposition of HE are amenable to predictive modelling. Experiments have been carried out on TNT, TATB and on two plastic-bonded HMX-based high explosives, LX-04 and LX-10. When the results … more
Date: May 24, 1976
Creator: Catalano, E.; McGuire, R.; Lee, E.; Wrenn, E.; Ornellas, D. & Walton, J.
Partner: UNT Libraries Government Documents Department
open access

A METHODOLOGY FOR DETERMINING THE DOSE RATE FOR BOUNDING MASS LIMITS IN A 9977 PACKAGING

Description: The Small Gram Quantity (SGQ) concept is based on the understanding that the hazards associated with the shipment of a radioactive material are directly proportional to its mass. This study describes a methodology that estimates the acceptable masses for several neutron and gamma emitting isotopes that can be shipped in a 9977 Package compliant with the Title 10 of the Code of Federal Regulations, Part 71 (10CFR71) external radiation level limits. 10CFR71.33 states that a shipping application i… more
Date: May 24, 2012
Creator: Abramczyk, G.; Bellamy, S.; Nathan, S. & Loftin, B.
Partner: UNT Libraries Government Documents Department
open access

H-CANYON AIR EXHAUST TUNNEL INSPECTION VEHICLE DEVELOPMENT

Description: The H-Canyon at Savannah River Site is a large concrete structure designed for chemical separation processes of radioactive material. The facility requires a large ventilation system to maintain negative pressure in process areas for radioactive contamination control and personnel protection. The ventilation exhaust is directed through a concrete tunnel under the facility which is approximately five feet wide and 8 feet tall that leads to a sand filter and stack. Acidic vapors in the exhaust ha… more
Date: May 24, 2011
Creator: Minichan, R.; Fogle, R. & Marzolf, A.
Partner: UNT Libraries Government Documents Department
open access

LSST Camera Optics Design

Description: The Large Synoptic Survey Telescope (LSST) uses a novel, three-mirror, telescope design feeding a camera system that includes a set of broad-band filters and three refractive corrector lenses to produce a flat field at the focal plane with a wide field of view. Optical design of the camera lenses and filters is integrated in with the optical design of telescope mirrors to optimize performance. We discuss the rationale for the LSST camera optics design, describe the methodology for fabricating, … more
Date: May 24, 2012
Creator: Riot, V. J.; Olivier, S.; Bauman, B.; Pratuch, S.; Seppala, L.; Gilmore, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Using Wireless Power Meters to Measure Energy Use of Miscellaneous and Electronic Devices in Buildings

Description: Miscellaneous and electronic devices consume about one-third of the primary energy used in U.S. buildings, and their energy use is increasing faster than other end-uses. Despite the success of policies, such as Energy Star, that promote more efficient miscellaneous and electronic products, much remains to be done to address the energy use of these devices if we are to achieve our energy and carbon reduction goals. Developing efficiency strategies for these products depends on better data about … more
Date: May 24, 2011
Creator: UC Berkeley, Berkeley, CA USA; Brown, Richard; Lanzisera, Steven; Cheung, Hoi Ying (Iris); Lai, Judy; Jiang, Xiaofan et al.
Partner: UNT Libraries Government Documents Department
open access

The Limits of Quintessence

Description: We present evidence that the simplest particle-physics scalar-field models of dynamical dark energy can be separated into distinct behaviors based on the acceleration or deceleration of the field as it evolves down its potential towards a zero minimum. We show that these models occupy narrow regions in the phase-plane of w and w', the dark energy equation-of-state and its time-derivative in units of the Hubble time. Restricting an energy scale of the dark energy microphysics limits how closely … more
Date: May 24, 2005
Creator: Caldwell, R.R. & Linder, Eric V.
Partner: UNT Libraries Government Documents Department
open access

Probing Reaction Dynamics of Transition-Metal Complexes in Solution via Time-Resolved X-ray Spectroscopy

Description: We report measurements of the photo-induced Fe(II) spin crossover reaction dynamics in solution via time-resolved x-ray absorption spectroscopy. EXAFS measurements reveal that the iron?nitrogen bond lengthens by 0.21+-0.03 Angstrom in the high-spin transient excited state relative to the ground state. XANES measurements at the Fe L-edge show directly the influence of the structural change on the ligand-field splitting of the Fe(II) 3d orbitals associated with the spin transition.
Date: May 24, 2009
Creator: Huse, Nils; Khalil, Munira; Kim, Tae Kyu; Smeigh, Amanda L.; Jamula, Lindsey; McCusker, James K. et al.
Partner: UNT Libraries Government Documents Department
open access

A Comparative experimental study of media access protocols for wireless radio networks

Description: We conduct a comparative experimental analysis of three well known media access protocols: 802.11, CSMA, and MACA for wireless radio networks. Both fixed and ad-hoc networks are considered. The experimental analysis was carried out using GloMoSim: a tool for simulating wireless networks. The main focus of experiments was to study how (i) the size of the network, (ii) number of open connections, (iii) the spatial location of individual connections, (iv) speed with which individual nodes move and… more
Date: May 24, 2001
Creator: Barrett, C. L. (Christopher L.); Drozda, M. (Martin) & Marathe, M. V. (Madhav V.)
Partner: UNT Libraries Government Documents Department
open access

Rapid Determination Of Radiostrontium In Large Soil Samples

Description: A new method for the determination of radiostrontium in large soil samples has been developed at the Savannah River Environmental Laboratory (Aiken, SC, USA) that allows rapid preconcentration and separation of strontium in large soil samples for the measurement of strontium isotopes by gas flow proportional counting. The need for rapid analyses in the event of a Radiological Dispersive Device (RDD) or Improvised Nuclear Device (IND) event is well-known. In addition, the recent accident at Fuku… more
Date: May 24, 2012
Creator: Maxwell, Sherrod L.; Culligan, Brian K. & Shaw, Patrick J.
Partner: UNT Libraries Government Documents Department
open access

Coupling Impedance of a Periodic Array of Diaphragms (Erratum)

Description: A method is presented for calculating the high-frequency longitudinal and transverse coupling impedances in a periodic array of diaphragms in a circular perfectly conducting pipe. The method is based on Weinstein's theory of diffraction of a plane electromagnetic wave on a stack of halfplanes. Using Weinstein's solution, it is shown that the problem of finding the beam field in the pipe reduces to an effective boundary condition at the radius of the diaphragms that couples the longitudinal elec… more
Date: May 24, 2012
Creator: Stupakov, G. V.
Partner: UNT Libraries Government Documents Department
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