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Pyle Wrote Life Story in Blood With GI's He Loved, Says Closest Friend Who Encouraged His Career (open access)

Pyle Wrote Life Story in Blood With GI's He Loved, Says Closest Friend Who Encouraged His Career

Newspaper article about the death and legacy of Ernie Pyle, a war correspondent who was recently killed in the war. Included is a cartoon depicting a typewriter next to a helmet with initials "E.P." and a caption that reads "'Brave Man:' Bill Mauldin, the soldiers' favorite artist, has drawn a cartoon in memory of Ernie Pyle, the soldier's favorite correspondent."
Date: April 23, 1945
Creator: Miller, Lee
System: The Portal to Texas History
Diffraction Radiation by a Line Charge Moving Past a Comb: A Model of Radiation Losses in an Electron Ring Accelerator (open access)

Diffraction Radiation by a Line Charge Moving Past a Comb: A Model of Radiation Losses in an Electron Ring Accelerator

A calculation is given of the radiated energy loss from a charged rod which moves at constant speed past an infinite set of parallel semi-infinite conducting plates of infinitesimal thickness, with the rod taken parallel to and at a fixed distance from the plate edges. The problem is analyzed using the Wiener-Hopf technique, and the resulting formulas are evaluated analytically in the limits of high rod speed and low rod speed, and compared with numerical evaluation over the full range of speeds.
Date: April 23, 1970
Creator: Hazeltine, R. D.; Rosenbluth, M. N. & Sessler, A. M.
System: The UNT Digital Library
200 kW neutral beam injection into the 2XII mirror device (open access)

200 kW neutral beam injection into the 2XII mirror device

None
Date: April 23, 1973
Creator: Coensgen, F. H.; Cummins, W. F.; Nexsen, W. E., Jr.; Molvik, A. W. & Simonen, T. C.
System: The UNT Digital Library
Dual-laser flow cytometry of single mammalian cells. [Performance of low-power argon and high-power krypton laser system for quantitative analysis and sorting of cells] (open access)

Dual-laser flow cytometry of single mammalian cells. [Performance of low-power argon and high-power krypton laser system for quantitative analysis and sorting of cells]

An improved dual-laser flow cytometric system for quantitative analysis and sorting of mammalian cells has been developed using a low-power argon and high-power krypton laser as illumination sources, thus permitting the excitation of fluorescent dyes having absorption regions ranging from the ultraviolet to infrared. Cells stained in liquid suspension with fluorescent dyes enter a flow chamber where they intersect two spatially separated laser beams. Separate pairs of quartz beam-shaping optics focus each beam onto the cell stream. Electro-optical sensors measure fluorescence and light scatter from cells that are processed electronically and displayed as frequency distribution histograms. Cells also can be electronically separated and microscopically identified. The ease and versatility of operation designed into this system represent a marked technological improvement for dual-laser excited flow systems. Details of this instrument are described along with illustrative examples of cells stained with mithramycin and rhodamine and analyzed for DNA content, total protein, and nuclear and cytoplasmic diameter.
Date: April 23, 1978
Creator: Steinkamp, J.A.; Orlicky, D.J. & Crissman, H.A.
System: The UNT Digital Library
Real-time delay monitor for flow-system cell sorters (open access)

Real-time delay monitor for flow-system cell sorters

For optimum performance in cell sorting, it is critical to assure proper timing in the charging of droplets to be deflected. A method for determining the transit delay time in cell sorters has been devised and applied to daily operation in the Los Alamos sorter systems. This delay monitor relies on detection of either scattered or absorbed light from cells in the fluid stream near the point of droplet breakoff.
Date: April 23, 1978
Creator: Martin, J.C.; McLaughlin, S.R. & Hiebert, R.D.
System: The UNT Digital Library
Energy coupling in the plasma focus (open access)

Energy coupling in the plasma focus

Experiments have been performed with a 125-kJ plasma focus to investigate mechanisms for rapid coupling of inductively-stored energy into plasmas. The coupling can take place through the formation of an electron or ion beam that deposits its energy in a target or directly by the penetration of the magnetic field into a resistive plasma. Some preliminary results from experiments of both types are described. The experiments use a replaceable conical anode tip that is intended to guide the focus to within a few millimeters of the axis, where it can suddenly deliver energy either to a small target or to particles that are accelerated. X-ray and fast-ion diagnostics have been used to study the effects.
Date: April 23, 1979
Creator: Wainwright, T. E.; Pickles, W. L.; Sahlin, H. L. & Price, D. F.
System: The UNT Digital Library
Monte Carlo Method for calculating fusion product behavior in field-reversed mirrors (open access)

Monte Carlo Method for calculating fusion product behavior in field-reversed mirrors

A unique model of fusion product (fp) slowing down and thermalization in field-reversed mirror (FRM) plasmas has been developed. It couples the Hill's spherical vortex representation of a field-reversed equilibrium with a monte carlo treatment of coulomb scattering, and thus provides a complete picture of fps from birth through their thermal diffusion. The incorporation of drag and scattering effects allows the code to address both the energy deposition and the ash buildup question. Results of several test cases are presented along with selected results from FRM studies.
Date: April 23, 1979
Creator: Driemeyer, D.; Miley, G. & Condit, W.
System: The UNT Digital Library
Permeability of generic repository rocks at simulated in situ conditions. [Comparison of Westerly granite and White Lake genissic granite] (open access)

Permeability of generic repository rocks at simulated in situ conditions. [Comparison of Westerly granite and White Lake genissic granite]

New laboratory data are reported on the effect of confining (lithostatic) pressure, pore-water pressure, and principal stress difference on permeability of Westerly granite and White Lake gneissic granite. Permeabilities as low as 10/sup -19/ cm/sup 2/ (10/sup -11/ D) have been measured successfully, using a transient technique. Principal strains, electrical conductivity, and compressional velocity are determined simultaneously. Applied loads on the 15-cm diameter by 28-cm long test sample are controlled automatically and all data are taken by a microcomputer. Results on the gneissic granite indicate permeabilities of 10/sup -18/ to 10/sup -19/ cm/sup 2/ that appear to be unaffected either by effective pressure or by stress. The granite yields permeabilities of 4x10/sup -16/ cm/sup 2/ that decrease by a factor of two with pressure and vary by a factor of two with stress. When compared to the initial value, compressional velocities increase by 4% and conductivity decreases by 50% as pressure is increased to 50 MPa in the gneissic granite. In granite, these become 3% and 58%, respectively. At pressure, loading of the granite of 0.5 of failure stress increases conductivity by about 20%.
Date: April 23, 1979
Creator: Heard, H.C.; Trimmer, D.; Duba, A. & Bonner, B.
System: The UNT Digital Library
Heat transfer in inertial confinement fusion reactor systems (open access)

Heat transfer in inertial confinement fusion reactor systems

The short time and deposition distance for the energy from inertial fusion products results in local peak power densities on the order of 10/sup 18/ watts/m/sup 3/. This paper presents an overview of the various inertial fusion reactor designs which attempt to reduce these peak power intensities and describes the heat transfer considerations for each design.
Date: April 23, 1980
Creator: Hovingh, J.
System: The UNT Digital Library
The AGS Booster high frequency rf system (open access)

The AGS Booster high frequency rf system

A high level rf system, including a power amplifier and cavity, has been designed and built for the AGS Booster. It covers a frequency range of 2.4 to 4.2 MHz and will be used to accelerate high intensity protons. Low intensity polarized protons and heavy ions, to the 1.5 GeV level. A total accelerating voltage of up to 90 kV will be provided by two cavities, each having two gaps. The internally cross coupled, pushpull cavities are driven by an adjacently located power amplifier. In order to accommodate beam intensities up to 0.75 {times} 10{sup 13} protons per bunch, a low plate resistance power tetrode is used. The tube anode is magnetically coupled to one of the cavity's two parallel cells. The amplifier is a grounded cathode configuration driven by a remotely located solid-state amplifier. It has been tested in the laboratory at full gap voltage with satisfactory results. 5 refs., 2 figs., 1 tab.
Date: April 23, 1991
Creator: Sanders, R.T.; Cameron, P.; Eng, W.; Goldman, M.A.; Jablonski, E.; Kasha, D. et al.
System: The UNT Digital Library
Partitioning between sediment and porewater of radiocesium from Chernobyl fallout (open access)

Partitioning between sediment and porewater of radiocesium from Chernobyl fallout

As part of a joint USA/USSR Environmental Agreement to determine the distribution and concentration of Chernobyl radioactivity in the northwest Black Sea area, the sediment from eight stations was collected and analyzed to assess the ability of sediment from the northwest Black Sea to adsorb radiocesium. Two methods were used to determine partitioning between liquid and solid phases; batch tests and porewater separation. In the batch test, Cs-137 tracer was added to mixtures of sediment and bottom water, with contact solutions ranging from 85 Bq/ml to 1760 Bq/ml. The distribution ratios (R{sub D}) for individual batch tests ranged from 390 to 1770 ml/g. Isotherms were linear for all cores and R{sub D} values calculated from the slopes of the isotherms ranged from 660 to 1660 ml/g. A second approach was used to determine the partitioning of Cs-137 between the porewater and the sediment under more natural conditions. The top 2 cm of two cores were sectioned and the sediment and the porewater were separated. In both samples the sediment contained significant amounts of Cs-137 and Cs-134 indicating the presence of fallout from the Chernobyl reactor accident. There was no cesium activity observed in the porewater at a minimum detectable level …
Date: April 23, 1991
Creator: Fuhrmann, M.; Pietrzak, R. (Brookhaven National Lab., Upton, NY (USA)); Neiheisel, J. & Dyer, R. (Environmental Protection Agency, Washington, DC (USA))
System: The UNT Digital Library
The Westinghouse Waste Isolation Division Management and Supervisor Training Program (open access)

The Westinghouse Waste Isolation Division Management and Supervisor Training Program

The Westinghouse Waste Isolation Division (WID) is the management and operating contractor (MOC) for the Department of Energy`s (DOE`s) Waste Isolation Plant (WIPP). Managers and supervisors at DOE facilities such as the WIPP are required to complete extensive training. To meet this requirement, WID created a self-paced, self-study program known as Management and Supervisor Training (MAST). All WID managers and supervisors are required to earn certification through the MAST program. Selected employees are permitted to participate in MAST with prior approval from their manager and the Human Resources Manager. Initial MAST certification requires the completion of 31 modules. MAST participants check out modules and read them when convenient. When they are prepared, participants take module examinations. To receive credit for a given module, participants must score at least 80 percent on the examination. Lessons learned from the development, implementation, and administration are presented in this paper.
Date: April 23, 1992
Creator: Gilbreath, B.
System: The UNT Digital Library
A Discharge-Flow/Chemiluminescence Study of the Reaction O + Si2H6 at Room Temperature (open access)

A Discharge-Flow/Chemiluminescence Study of the Reaction O + Si2H6 at Room Temperature

Article on a discharge-flow/chemiluminescence study of the reaction O + Si2H6 at room temperature.
Date: April 23, 1993
Creator: Taylor, Craig A. & Marshall, Paul
System: The UNT Digital Library
Freeze-out and the failure of Richtmyer`s prescription (open access)

Freeze-out and the failure of Richtmyer`s prescription

In the standard Richtmyer-Meshkov instability, perturbations at a shocked interface grow after the passage of a shock. Freeze-out refers to the phenomenon whereby the perturbations do not grow, i.e., freeze-out, after the passage of a shock. This is fairly straightforward, at least theoretically (no experiments have been done so far) in a doubly shocked system. The first shock induces a growth which can be completely neutralized by a second shock, provided that the direction and the strength and timing of the second shock are properly chosen. This type of double-shock freeze-out occurs in compressible as well as incompressible fluids, and is easy to understand. Somewhat more subtle is single-shock freeze-out; in the pursuit of this phenomenon, the author found that in certain cases Richtmyer`s prescription fails to give the correct growth rate.
Date: April 23, 1993
Creator: Mikaelian, K. O.
System: The UNT Digital Library
Fatigue of LX-14 and LX-19 plastic bonded explosives (open access)

Fatigue of LX-14 and LX-19 plastic bonded explosives

The DOD uses the plastic bonded explosive (PBX) LX-14 in a wide variety of applications including shaped charges and explosively forged projectiles. LX- 19 is a higher energy explosive, which could be easily substituted for LX-14 because it contains the identical Estane 5703p binder and more energetic CL-20 explosive. Delivery systems for large shaped charges, such as TOW-2, include the Apache helicopter. Loads associated with vibrations and expansion from thermal excursions in field operations may, even at low levels over long time periods, cause flaws, already present in the PBX to grow. Flaws near the explosive/liner interface of a shaped charge can reduce performance. Small flaws in explosives are one mechanism (the hot spot mechanism) proposed for initiation and growth to detonation of PBXs like LX-14, PBXN 5, LX-04 and LX-17 among others. Unlike cast-cured explosives and propellants, PBXs cannot usually be compression molded to full density. Generally, the amount of explosive ignited by a shock wave is approximately equal to the original void volume. Whether or not these flaws or cracks grow during field operations to an extent sufficient to adversely affect the shaped charge performance or increase the vulnerability of the PBX is the ultimate question this effort …
Date: April 23, 1998
Creator: Hoffman, D. M., LLNL
System: The UNT Digital Library
Risk assessment of high altitude free flight commercial aircraft operations (open access)

Risk assessment of high altitude free flight commercial aircraft operations

A quantitative model is under development to assess the safety and efficiency of commercial aircraft operations under the Free Flight Program proposed for air traffic control for the US National Airspace System. The major objective of the Free Flight Program is to accommodate the dramatic growth anticipated in air traffic in the US. However, the potential impacts upon aircraft safety from implementing the Program have not been fully explored and evaluated. The model is directed at assessing aircraft operations at high altitude over the continental US airspace since this action is the initial step for Free Flight. Sequential steps with analysis, assessment, evaluation, and iteration will be required to satisfactorily accomplish the complete transition of US commercial aircraft traffic operations.
Date: April 23, 1998
Creator: Kimura, C. Y.; Sandquist, G. M.; Slaughter, D. M. & Sanzo, D. L.
System: The UNT Digital Library
Role of the NIF in the development of ICF applications (open access)

Role of the NIF in the development of ICF applications

The National Ignition Facility (NIF) is a 1.8 MJ (at 351 nm), 192 beam laser facility being built at the Lawrence Livermore National Laboratory (LLNL) to achieve inertial fusion ignition in the laboratory. The NIF Project is being designed and built by a team from LLNL, Los Alamos National Laboratory, Sandia National Laboratory, and the University of Rochester. When completed in 2003, it will be a multipurpose facility that will be used for many applications in national security, energy, and the basic sciences. In addition to the National Security Mission, these applications include, for example, electric power generation, space propulsion, and study of basic astrophysical phenomena in the laboratory. Such applications receive benefit both through the state- of-the-art technology developments necessary to build NIF and through specific experiments that will be performed on NIF.
Date: April 23, 1998
Creator: Hogan, W.
System: The UNT Digital Library
Solubility of Anthracene in Binary Alkane + 2-Ethyl-1-hexanol and Alkane + 1-Pentanol Solvent Mixtures at 298.2 K (open access)

Solubility of Anthracene in Binary Alkane + 2-Ethyl-1-hexanol and Alkane + 1-Pentanol Solvent Mixtures at 298.2 K

Article on the solubility of anthracene in binary alkane + 2-ethyl-1-hexanol and alkane + 1-pentanol solvent mixtures at 298.2 K.
Date: April 23, 1998
Creator: Roy, Lindsay Elizabeth; Hernández, Carmen E.; Reddy, Gaddum D.; Sanders, Jessica T.; Deng, Taihe; Tuggle, Michael B. et al.
System: The UNT Digital Library
(129)Xe NMR of Mesoporous Silicas (open access)

(129)Xe NMR of Mesoporous Silicas

The porosities of three mesoporous silica materials were characterized with {sup 129}Xe NMR spectroscopy. The materials were synthesized by a sol-gel process with r = 0, 25, and 70% methanol by weight in an aqueous cetyltrimethylammonium bromide solution. Temperature dependent chemical shifts and spin lattice relaxation times reveal that xenon does not penetrate the pores of the largely disordered (r= 70%) silica. For both r = 0 and 25%, temperature dependent resonances corresponding to physisorbed xenon were observed. An additional resonance for the r = 25% sample was attributed to xenon between the disordered cylindrical pores. 2D NMR exchange experiments corroborate the spin lattice relaxation data which show that xenon is in rapid exchange between the adsorbed and the gas phase.
Date: April 23, 1999
Creator: Anderson, M.T.; Asink, R.A.; Kneller, J.M. & Pietrass, T.
System: The UNT Digital Library
Amorphization of Laves-Phase Precipitates in Zircaloy-4 by Neutron Irradiation (open access)

Amorphization of Laves-Phase Precipitates in Zircaloy-4 by Neutron Irradiation

Examination of corrosion coupons by transmission electron microscopy after their exposure in the Idaho Advanced Test Reactor (ATR) has broadened the Zircaloy-4 precipitate-amorphization database and validated a new kinetic model for previously unavailable values of temperature and fast-neutron flux. The model describes the amorphization of Zr(Fe,Cr){sub 2} intermetallic precipitates in zirconium alloys as a dynamic competition between radiation damage and thermal annealing that leaves some iron atoms available for flux-assisted diffusion to the zirconium matrix. It predicts the width of the amorphous zone as a function of neutron flux (E>1 MeV), temperature, and time. In its simplest form, the model treats the crystalline/amorphous and precipitate/matrix interfaces as parallel planes, and its accuracy decreases for small precipitates and high fluence as the amorphous-zone width approaches precipitate dimensions. The simplest form of the model also considers diffusion to be rate-determining. This is an accurate approximation for steady-state conditions or slow changes in flux and temperature, but inappropriate for the analysis of faster transients. The paper addresses several difficulties inherent in measuring amorphous-zone width, and utilizes the expanded database to evaluate the improvements in predictive accuracy available through both conversion of the model to spherical coordinates and extension of its time dependency.
Date: April 23, 1999
Creator: Peters, H. R.; Taylor, D. F. & Yang, Walter J. S.
System: The UNT Digital Library
A calculation of the dynamic aperture of the LHC (open access)

A calculation of the dynamic aperture of the LHC

The dynamic aperture for version 5.1, with a 300{mu}r crossing angle at IP1 and IP5, of the Large Hadron Collider (LHC) lattice has been estimated using the tracking code TEVLAT. The dynamic aperture calculated here is due to the magnetic field errors in the high gradient quadrupoles (MQX) in the two low-{beta} interaction regions at IR1 and IR5. No errors were assigned to the magnets in the arc regions of the lattice, nor were beam-beam effects incorporated. The dynamic aperture is expressed in terms of the {sigma} of the beam corresponding to the beam emittance of 3.75mm mr. With only short term tracking, the combined effect of the multipoles and the crossing angle is to yield an average (over multipole coefficients generated with 100 different seeds) dynamic aperture of {approx} 11.7 {plus_minus} 1.2{sigma}.
Date: April 23, 1999
Creator: Gelfand, Norman M.
System: The UNT Digital Library
A Comparison of 1 T(Omega) and 10 T (Omega) High Resistance Standards Between NIST and Sandia (open access)

A Comparison of 1 T(Omega) and 10 T (Omega) High Resistance Standards Between NIST and Sandia

NIST-built 10 T{Omega} and commercial 1 T{Omega} standard resistors were hand carried between NIST and Sandia for a high resistance comparison. The comparison tested the ruggedness of the new NIST-built standard resistors, provided a check of the scaling between the two laboratories, supported measurements to reestablish NIST calibration services at 10 T{Omega} and 100 T{Omega}, and demonstrated the possibility of establishing a NIST high resistance measurement assurance program (MAP). The comparison has demonstrated agreement on the order of 0.07% which is within the expanded uncertainties (coverage factor = 2) of NIST and Sandia at 1 T{Omega} and 10 T{Omega}.
Date: April 23, 1999
Creator: Jarrett, Dean G.; Dziuba, Ronald F. & Kraft, Marlin E.
System: The UNT Digital Library
Cosmological constraints on theories with large extra dimensions (open access)

Cosmological constraints on theories with large extra dimensions

In theories with large extra dimensions, constraints from cosmology lead to non-trivial lower bounds on the gravitational scale M, corresponding to upper bounds on the radii of the compact extra dimensions. These constraints are especially relevant to the case of two extra dimensions, since only if M is 10 TeV or less do deviations from the standard gravitational force law become evident at distances accessible to planned sub-mm gravity experiments. By examining the graviton decay contribution to the cosmic diffuse gamma radiation, we derive, for the case of two extra dimensions, a conservative bound M > 110TeV, corresponding to r{sub 2} < 5.1 x 10{sup -5} mm, well beyond the reach of these experiments. We also consider the constraint coming from graviton overclosure of the universe and derive an independent bound M > 6.5/{radical}h TeV, or r{sub 2} < .015hmm.
Date: April 23, 1999
Creator: Hall, Lawrence J. & Smith, David
System: The UNT Digital Library
Front-flash thermal imaging characterization of continuous fiber ceramic composites. (open access)

Front-flash thermal imaging characterization of continuous fiber ceramic composites.

Infrared thermal imaging has become increasingly popular as a nondestructive evaluation method for characterizing materials and detecting defects. One technique, which was utilized in this study, is front-flash thermal imaging. We have developed a thermal imaging system that uses this technique to characterize advanced material systems, including continuous fiber ceramic composite (CFCC) components. In a front-flash test, pulsed heat energy is applied to the surface of a sample, and decay of the surface temperature is then measured by the thermal imaging system. CFCC samples with drilled flat-bottom holes at the back surface (to serve as ''flaws'') were examined. The surface-temperature/time relationship was analyzed to determine the depths of the flaws from the front surface of the CFCC material. Experimental results on carbon/carbon and CFCC samples are presented and discussed.
Date: April 23, 1999
Creator: Deemer, C.
System: The UNT Digital Library