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Calibration of a Hopkinson bar with a transfer standard

Description: 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.
Partner: UNT Libraries Government Documents Department
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Head assembly for multiposition borehole extensometer

Description: 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.
Partner: UNT Libraries Government Documents Department
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A Mechanism Explaining the Instability of EBR-I, Mark III

Description: 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.
Partner: UNT Libraries Government Documents Department
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Metallurgy of continuous filamentary A15 superconductors

Description: 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
Partner: UNT Libraries Government Documents Department
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Fuel Cycle Program, a Boiling Water Reactor Research and Development Program. Third Quarterly Report, January 1961-March 1961

Description: The continuing analysis of the VBWR core resulted in refinements in the calculations for reactivity in voids, flux leakage and resonance escape probability. The Zircaloy cladding for 25 fuel assemblies was received and passed inspection. Preliminary measurements of VBWR flux oscillations, used to develop instrumentation and data interpretation techniques, showed random normally-distributed oscillations with a predominant frequency of 0.5 to 1.0 cycles/second. A model for analog computer simulat… more
Date: October 31, 1961
Partner: UNT Libraries Government Documents Department
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Comparison of multidimensional calculations of long-rod impacts on oblique plates

Description: 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))
Partner: UNT Libraries Government Documents Department
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INVESTIGATION OF THE TECHNICAL FEASIBILITY OF COLD EXTRUSION FOR ZIRCALOY-2 TUBING PRODUCTION. Quarterly Technical Progress Report No. 3, April-June 1961

Description: Investigations are being made to establish the feasibility of using cold extrusion to produce Zircaloy-2 tubular products. Tests on extruding 1 1/4-in. diameter billets were completed. Samples in 46 bar-extrusion tests were extruded with 80% reduction at 400 deg C. Severe lubricant breakdown occurred. Piercing tests were conducted at, room temperature and 200 deg C, using 50% reduction and a 140-degree conical punch profile. Good extrusions were obtained in forraing 1.07-in. OD x 0.052-in. wall… more
Date: October 31, 1962
Creator: Weil, F.E. & Hill, J.G.
Partner: UNT Libraries Government Documents Department
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The GTP binding protein-dependent activation and deactivation of cGMP phosphodiesterase in rod photoreceptors

Description: 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.
Partner: UNT Libraries Government Documents Department
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X-ray gauge monitoring of LLNL replica carbon production process

Description: 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.
Partner: UNT Libraries Government Documents Department
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Simplified design methods for nonlinear dynamic mechanical systems

Description: 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.
Partner: UNT Libraries Government Documents Department
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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

Description: 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.
Partner: UNT Libraries Government Documents Department
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Axially accelerated saboted rods subjected to lateral forces

Description: 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.
Partner: UNT Libraries Government Documents Department
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Thermal striping of a rod: Thermoelastic solution for sinusoidal fluid temperature

Description: 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.
Partner: UNT Libraries Government Documents Department
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Criterion for the prevention of core fracture during extrusion of bimetal rods

Description: 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.
Partner: UNT Libraries Government Documents Department
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Noncontact material testing using laser energy deposition and interferometry

Description: 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.
Partner: UNT Libraries Government Documents Department
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Computer simulations to study the effect of adiabatic heating on rod penetration

Description: 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.
Partner: UNT Libraries Government Documents Department
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Revised financial analysis of experimental releases conducted at Glen Canyon Dam during water years 1997 through 2005.

Description: 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.
Partner: UNT Libraries Government Documents Department
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Summary of criticality data obtained at Battelle Pacific Northwest Laboratories on fixed and soluble poisons in U + Pu nitrate solutions

Description: 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.
Partner: UNT Libraries Government Documents Department
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Analysis of urine samples for iron and S{sup 35}

Description: 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.
Partner: UNT Libraries Government Documents Department
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TEMPERATURE DISTRIBUTION AND THERMAL STRESSES IN A SLAB WITH EXPONENTAL HEAT SOURCE

Description: BS>Temperatures and temperature gradients from gamma heating in reactor components are treated for more complicated cases thnn are found in the literature. A summary of available solutions for conditions which may arise in designing the reactor vessel and its components is attempted. The basic stress formula for the case of an exponential heat source in slab geometry is derived, into which the appropriate temperature equation can be inserted. (T.R.H.)
Date: January 1, 1961
Creator: Menzel, H.F.
Partner: UNT Libraries Government Documents Department
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