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in subjects: "Rods"

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Calibration of a Hopkinson bar with a transfer standard

During the past year, program field test temperatures, that are beyond the test accelerometer operational limits of {minus}30{degrees}F and +150{degrees}F, required the calibration of accelerometers at high shock levels and at the temperature extremes of {minus}50{degrees}F and +160{degrees}F. The purposes of these calibrations were to insure the accelerometers operated at the field test temperatures and to provide an accelerometer sensitivity at each test temperature. Since there is no NIST-tr… more

Date: January 1, 1991

Creator: Bateman, V. I.; Leisher, W. B.; Brown, F. A. & Davie, N. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Head assembly for multiposition borehole extensometer

A head assembly for a borehole extensometer and an improved extensometer for measuring subsurface subsidence. A plurality of inflatable anchors provide discrete measurement points. A metering rod is fixed to each of the anchors which are displaced when subsidence occurs, thereby translating the attached rod. The head assembly includes a sprocket wheel rotatably mounted on a standpipe and engaged by a chain which is connected at one end to the metering rod and at the other end to a counterweight… more

Date: June 9, 1981

Creator: Frank, D.N.

Item Type: Patent

Partner: UNT Libraries Government Documents Department

open access

A Mechanism Explaining the Instability of EBR-I, Mark III

Presented at the International Atomic Energy Agencysponsored Seminar on the Physics of Fast and Intermediate Reactors. Vienna, August 3-11, 196l. A feedback model, was developed to account for resonant instabilities in the Mark II core. In this model, the prompt positive power coefficient effect is ascribed to fuel rod bowing and the delayed negative power coefficient effect to thermally lnduced motions in the lower shield plate. Since this model is supported by observations, it is concluded th… more

Date: September 1, 1961

Creator: Smith, R. R.; Matlock, R. G.; McGinnis, F. D.; Novick, M. & Thalgott, F. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Metallurgy of continuous filamentary A15 superconductors

The early history of the bronze process is recapitulated and modifications to the process which have since followed are described. The metallurgical principles, which are involved in the process, are described including the kinetics of the compound growth, the effects of additives on the growth, etc. The superconducting properties of these compounds are also discussed. The influence of metallurgical variables on the superconducting properties is discussed in detail. In discussing the supercondu… more

Date: January 1, 1980

Creator: Suenaga, M

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Comparison of multidimensional calculations of long-rod impacts on oblique plates

The justification for three-dimensional versus two-dimensional simulations of non-symmetric armor penetration problems has been a topic of discussion for many years. Two-dimensional plane-strain approximations are generally not quantitatively accurate, especially at later times, but they can be performed efficiently and the results are usually acceptable. Although three-dimensional calculations provide better results, they are very time consuming and expensive to perform. But with the improved … more

Date: January 1, 1989

Creator: Fujita, R.K. & Cort, G.E. (Los Alamos National Lab., NM (USA))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The GTP binding protein-dependent activation and deactivation of cGMP phosphodiesterase in rod photoreceptors

Cyclic GMP (cGMP) has a crucial role in visual transduction. Recent electrophysiological studies clearly indicate the existence of cGMP-activated conductance in photoreceptor plasma membranes. In darkness, Na{sup +}, Ca{sup ++}, and Mg{sup ++} enter rod outer segments (ROS) through cGMP-activated channels while light closes channels by lowering cGMP concentrations through activation of cGMP phosphodiesterase (PDE). Many excellent reviews reference the mechanism of PDE activation in photorecepto… more

Date: January 1, 1989

Creator: Yamazaki, Akio.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Solid hosts for dye laser rods: Part 2, Some experimental results

Attempts and problems encountered in producing high quality polymer dye laser rods are discussed. Purification methods used on the monomer materials, curing agent problems, and gamma radiation curing are considered. 7 figs.

Date: January 1, 1987

Creator: Erickson, G.F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

X-ray gauge monitoring of LLNL replica carbon production process

This report contains results of a series of x-ray gauging measurements performed on bars tracked through the LLNL replica carbon production process. We were tasked with monitoring a few salt bars through the entire production process to identify any possible problem areas. The process consists of five major steps: pressing fine sodium chloride crystals into a uniform salt bar, sintering the salt bar, infusing the bar with a phenolic polymer solution and convection oven drying it to remove the a… more

Date: December 1, 1990

Creator: Lewis, D.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Simplified design methods for nonlinear dynamic mechanical systems

Dimensional analysis and classical methods are combined in a novel way to develop a simplified mathematical description of two practical nonlinear dynamic mechanical systems experiencing excitation similar to that due to an earthquake. This method is used to obtain system descriptions in closed algebraic form with appropriate constants. The number of constants provides the designer with the minimum number of complex time-history analyses (or tests) required to characterize the systems completel… more

Date: January 1, 1979

Creator: Frick, T.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Investigation of the effects of particle size on the mechanical properties of porous and tin infiltrated niobium rods fabricated by a thermoplastic-powder metallurgy technique

An investigation was made of the influence of particle size on the properties of both porous and tin infiltrated niobium rods fabricated by a thermoplastic-powder metallurgy technique. The residual porosity, extrusion pressure, tensile strength, and ductility were found to be dependent on the particle size distribution. All of these parameters were found to increase with increasing particle size. The influence of sintering time at a temperature of 2250/sup 0/C was also studied. With increasing … more

Date: December 1, 1978

Creator: Noman, A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Axially accelerated saboted rods subjected to lateral forces

Considerable effort has been dedicated to ensuring the structural integrity of long rods during axial acceleration, but little work has addressed the subject of lateral acceleration of the sabot/rod package while it is still in-bore. Drysdale states ''Certainly the most pressing unsolved problem facing the projectile designer at the present time does not involve structural integrity directly. Rather it is the development of a methodology which allows the rational design of in-bore configuration… more

Date: January 1, 1989

Creator: Rabern, D.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Thermal striping of a rod: Thermoelastic solution for sinusoidal fluid temperature

A numerical solution is obtained for the one-dimensional temperature distribution in a rod which is assumed to be immersed in a fluid of sinusoidally-varying temperature. Readily available stress equations are combined with the thermal solution to perform a structural analysis in which all stresses are assumed to be within the elastic limit of the material. This leads to a parametric set of dimensionless curves which explain the interaction of the relevant parameters, such as the rod size and m… more

Date: January 1, 1990

Creator: Feldman, E. E.; Chang, L. K. & Lee, M. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Criterion for the prevention of core fracture during extrusion of bimetal rods

Based on the upper-bound theorem in limit analysis, a theoretical model for core fracture in bimetal rods during extrusion has been developed and a fracture criterion established. The variables affecting core fracture are: reduction in area (r%), die geometry, friction (m), relative size of the core and relative strength of the core. Within the wide range of possible combinations of these process variables, only a small range permits extrusion without fracture. With suitable modifications the p… more

Date: September 1, 1980

Creator: Avitzur, B.; Wu, R.; Talbert, S. & Chou, Y.T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Noncontact material testing using laser energy deposition and interferometry

A technique is described for the noncontact testing of materials using laser deposition to generate a stress pulse and interferometry to record the transient surface displacement. The dilatational wave speed can be measured and, in the particular case of rod or plate specimens, sufficient information can be obtained to evaluate the two elastic constants of an isotropic material. Several applications illustrating the advantages of the approach are summarized.

Date: February 6, 1978

Creator: Calder, C.A. & Wilcox, W.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Computer simulations to study the effect of adiabatic heating on rod penetration

We use computer simulations to help us understand the experimental observation that depleted uranium (DU) rods penetrate more steel than equal density tungsten alloy (WA) rods, and that this advantage depends on velocity and fineness ratio. Our simulations used thermal softening. Although the DU rods exhibit shear fracture instead, both phenomena result in a loss of hoop strength, and help to keep the projectile residue from interfering with the incoming rod. Our simulations show that rods of D… more

Date: August 1, 1993

Creator: Reaugh, J. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Revised financial analysis of experimental releases conducted at Glen Canyon Dam during water years 1997 through 2005.

Because of concerns about the impact that Glen Canyon Dam (GCD) operations were having on downstream ecosystems and endangered species, the Bureau of Reclamation (Reclamation) conducted an Environmental Impact Statement (EIS) on dam operations (DOE 1996). New operating rules and management goals for GCD that had been specified in the Record of Decision (ROD) (Reclamation 1996) were adopted in February 1997. In addition to issuing new operating criteria, the ROD mandated experimental releases fo… more

Date: January 11, 2011

Creator: Veselka, T. D.; Poch, L. A.; Palmer, C. S.; Loftin, S.; Osiek, B.; Sciences, Decision and Information et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Summary of criticality data obtained at Battelle Pacific Northwest Laboratories on fixed and soluble poisons in U + Pu nitrate solutions

Knowledge of the effects of neutron poisons on U +Pu systems is necessary to better establish criticality safety programs. These data are needed in setting of criticality safety specifications for storage, processing and shipping of fissile material where it is desired to handle larger quantities with safety and efficiency. These data are needed also for validating calculational techniques and cross sections sets. U + Pu solutions containing 30% Pu in the total U + Pu were used in these experim… more

Date: April 1, 1976

Creator: Lloyd, R. C. & Clayton, E. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Analysis of urine samples for iron and S{sup 35}

On August 21, 1948, several smear samples of contamination from the inner rod room at 100-F Area were submitted for beta identification. This contamination was spread as a result of maintenance work on the horizontal rods. Urine sample were deemed advisable for two men who had been exposed while working on the rods. These urine samples were also submitted for beta analyses. The analyses of the smears showed the contamination to consist of primarily S{sup 35} (65%) and Fe{sup 59} (30%)and minor … more

Date: November 23, 1948

Creator: Thornburn, R. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Resonance Absorption in Thorium Metal and Oxide Rods. Final Report

No Description Available.

Date: November 1, 1963

Creator: Pettus, W. G.; Baldwin, M. N. & Samuel, C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Structure of ZnO Nanorods using X-ray Diffraction

Many properties of zinc oxide, including wide bandgap semiconductivity, photoconductivity, and chemical sensing, make it a very promising material for areas such as optoelectronics and sensors. This research involves analysis of the formation, or nucleation, of zinc oxide by electrochemical deposition in order to gain a better understanding of the effect of different controlled parameters on the subsequently formed nanostructures. Electrochemical deposition involves the application of a potenti… more

Date: November 7, 2007

Creator: Howdyshell, Marci & /SLAC, /Albion Coll.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Investigation of a thermoplastic-powder metallurgy process for the fabrication of porous niobium rods

The feasibility of using a thermoplastic-powder metallurgy technique for the fabrication of porous niobium rods was investigated. Some early problems were overcome to successfully extrude the polymer coated niobium powder into long lengths. The effects of certain process variables were investigated. Residual porosity and extrusion pressure were found to be regulated by the polymer fraction. The procedures for taking the extruded polystyrene--niobium rods through the heat treatments to the final… more

Date: June 1, 1978

Creator: Nordin, D. R.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Thermal conductivity of hydrogen doped high purity vanadium

The electrical resistivity, thermal conductivity, and Seebeck coefficient of three hydrogen doped high purity vanadium rods have been measured during heating from 77 K to 300 K. Correlations are made of the anomalous effects observed in two of the samples with the temperature of transformation from a hydride in a solid solution matrix to a solid solution. An increase in electrical resistivity is observed after thermal cycling but no apparent change in transformation temperature was observed.

Date: March 1, 1977

Creator: Courtney, D. R.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

open access

Heavy metals processing near-net-forming summary progress report

This study utilized a converging-diverging nozzle to spray-form an alloy having a weight percent composition of 49.6% iron, 49.6% tungsten, and 0.8% carbon into samples for analysis. The alloy was a surrogate that displayed metallurgical characteristics similar to the alloys used in the heavy metals processing industry. US DOE facilities are evaluating advanced technologies which can simplify component fabrication, reduce handling steps, and minimize final machining. The goal of producing net-s… more

Date: September 1994

Creator: Watson, L. D. & Thompson, J. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Analysis of fracture modes during extrusion and drawing of bimetal rods or wire. Analytical study of drawing and extrusion of superconducting filamentary wires: fracture problems and evaluation of temperature rise. Final report

Based on the upper-bound theorem in limit analysis, a theoretical model describing sound flow, core fracture, and sleeve fracture in bimetal rods and wire during extrusion and drawing was developed. The variables affecting core and sleeve fracture are: reduction in area, die geometry, friction, relative size and strength of the core, and applied surface tractions. Within the wide range of combinations of these process variables, only a small range permits co-extrusion and codrawing without frac… more

Date: January 9, 1984

Creator: Avitzur, B.; Wu, R.; Chou, Y.T. & Talbert, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department