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Rock mechanics for hard rock nuclear waste repositories (open access)

Rock mechanics for hard rock nuclear waste repositories

The mined geologic burial of high level nuclear waste is now the favored option for disposal. The US National Waste Terminal Storage Program designed to achieve this disposal includes an extensive rock mechanics component related to the design of the wastes repositories. The plan currently considers five candidate rock types. This paper deals with the three hard rocks among them: basalt, granite, and tuff. Their behavior is governed by geological discontinuities. Salt and shale, which exhibit behavior closer to that of a continuum, are not considered here. This paper discusses both the generic rock mechanics R and D, which are required for repository design, as well as examples of projects related to hard rock waste storage. The examples include programs in basalt (Hanford/Washington), in granitic rocks (Climax/Nevada Test Site, Idaho Springs/Colorado, Pinawa/Canada, Oracle/Arizona, and Stripa/Sweden), and in tuff (Nevada Test Site).
Date: September 1, 1981
Creator: Heuze, F.E.
System: The UNT Digital Library
Nuclear waste repository characterization: a spatial estimation/identification approach (open access)

Nuclear waste repository characterization: a spatial estimation/identification approach

This paper considers the application of spatial estimation techniques to a groundwater aquifer and geological borehole data. It investigates the adequacy of these techniques to reliably develop contour maps from various data sets. The practice of spatial estimation is discussed and the estimator is then applied to a groundwater aquifer system and a deep geological formation. It is shown that the various statistical models must first be identified from the data and evaluated before reasonable results can be expected.
Date: March 1, 1981
Creator: Candy, J.V. & Mao, N.
System: The UNT Digital Library
Geomechanics of the Climax mine-by, Nevada Test Site (open access)

Geomechanics of the Climax mine-by, Nevada Test Site

A generic test of retrievable geologic storage of spent fuel assemblies in an underground chamber is being conducted at the Nevada Test Site. The horizontal shrinkage of the pillars is not explainable, but the vertical pillar stresses are easily understood. A two-phase project was initiated to estimate the in-situ deformability of the Climax granite and to refine the in-situ stress field data, and to model the mine-by. (DLC)
Date: March 1, 1981
Creator: Heuze, F.E.
System: The UNT Digital Library
Thermochemical Investigations of Nearly Ideal Binary Solvents 7: Monomer and Dimer Models for Solubility of Benzoic Acid in Simple Binary and Ternary Solvents (open access)

Thermochemical Investigations of Nearly Ideal Binary Solvents 7: Monomer and Dimer Models for Solubility of Benzoic Acid in Simple Binary and Ternary Solvents

Article on thermochemical investigations of nearly ideal binary solvents and monomer and dimer models for solubility of benzoic acid in simple binary and ternary solvents.
Date: September 1, 1981
Creator: Acree, William E. (William Eugene) & Bertrand, Gary L.
System: The UNT Digital Library
Fourier-Transform Analysis of Normal Photoelectron Diffraction Data for Surface-Structure Determination (open access)

Fourier-Transform Analysis of Normal Photoelectron Diffraction Data for Surface-Structure Determination

A direct method for surface-structure determination from normal emission photoelectron diffraction (NPD) data is presented. Fourier transforms of the calculated NPD intensities yield peaks at adsorbate-substrate normal interlayer distances. Applications are demonstrated using theoretical NPD curves for the Se/Ni system calculated by dynamical theory. These results show that interplanar spacings between the overlayer and as many as four substrate layers could be determined with an accuracy of better than 3%.
Date: May 1, 1981
Creator: Hussain, Z.; Shirley, D. A.; Li, C. H. & Tong, S. Y.
System: The UNT Digital Library
Quantitative Studies of Thermal Shock in Ceramics Based on a Novel Test Technique (open access)

Quantitative Studies of Thermal Shock in Ceramics Based on a Novel Test Technique

A thermal shock test has been designed which permits the thermal fracture resistance and the mechanical strength of brittle materials to be quantitatively correlated. Thermal shock·results for two materials, Al{sub 2}O{sub 3} and SiC, have been accurately predicted from biaxial strength measurements and a transient thermal stress analysis (performed using a finite element method). General implications for the prediction of thermal shock resistance, with special reference to ceramic components, are discussed.
Date: May 1, 1981
Creator: Faber, K. T.; Huang, M. D. & Evans, A. G.
System: The UNT Digital Library
FINGERPRINTING INORGANIC ARSENIC AND ORGANOARSENIC COMPOUNDS IN IN SITU OIL SHALE RETORT AND PROCESS VOTERS USING A LIQUID CHROMATOGRAPH COUPLED WITH AN ATOMIC ABSORPTION SPECTROMETER AS A DETECTOR (open access)

FINGERPRINTING INORGANIC ARSENIC AND ORGANOARSENIC COMPOUNDS IN IN SITU OIL SHALE RETORT AND PROCESS VOTERS USING A LIQUID CHROMATOGRAPH COUPLED WITH AN ATOMIC ABSORPTION SPECTROMETER AS A DETECTOR

Inorganic arsenic and organoarsenic compounds were speciated in seven oil shale retort and process waters, including samples from simulated, true and modified in situ processes, using a high performance liquid chromatograph automatically coupled to a graphite furnace atomic absorption detector. The molecular forms of arsenic at ppm levels (({micro}g/mL) in these waters are identified for the first time, and shown to include arsenate, methylarsonic acid and phenylarsonic acid. An arsenic-specific fingerprint chromatogram of each retort or process water studied has significant impliestions regarding those arsenical species found and those marginally detected, such as dimethylarsinic acid and the suspected carcinogen arsenite. The method demonstrated suggests future means for quantifying environmental impacts of bioactive organometal species involved in oil shale retorting technology.
Date: July 1, 1981
Creator: Fish, Richard H.; Brinckman, Frederick E. & Jewett, Kenneth L.
System: The UNT Digital Library
Ferrite Structure and Mechanical Properties of Low Alloy Duplex Steels (open access)

Ferrite Structure and Mechanical Properties of Low Alloy Duplex Steels

The purpose of this communication is threefold. 1) To confirm the presence of and to characterize the precipitates in the ferrite phase of the base + Nb and base + Mo steels, 2) to study any possible variation in precipitate density as the martensitic volume fraction is changed and 3) to determine the level of precipitation strengthening.
Date: April 1, 1981
Creator: Hoel, R. H. & Thomas, G.
System: The UNT Digital Library
EVIDENCE FOR SPIN FLUCTUATIONS IN THE DEEP INELASTIC REACTION {sup 165}Ho + {sup 165}Ho AT 8.5 MeV/amu (open access)

EVIDENCE FOR SPIN FLUCTUATIONS IN THE DEEP INELASTIC REACTION {sup 165}Ho + {sup 165}Ho AT 8.5 MeV/amu

Both the magnitude and alignment of the transferred angular momentum in the reaction {sup 165}Ho + {sup 165}Ho have been measured as a function of Q-value via continuum {gamma}-ray multiplicity and anisotropy techniques. The spin transfer and the continuum {gamma}-ray anisotropy increase throughout the quasielastic region. The spin transfer as a function of Q-value saturates at ~35{bar h}/fragment, the anisotropy peaks at a value of ~2 and then decreases to near unity for the largest Q-values. The observed anisotropies are in good agreement with predictions from an equilibrium statistical model in which thermal excitation of angular-momentum-bearing collective modes and neutron evaporation give rise to in-plane components of the angular momentum.
Date: May 1, 1981
Creator: McDonald, R. J.; Pacheco, A. J.; Wozniak, G. J.; Bolotin, H. H.; Moretto, L. G.; Schuk, C. et al.
System: The UNT Digital Library
High Resolution Scanning Auger Microscopic Investigation of Intergranular Fracture in as-Quenched Fe-12Mn (open access)

High Resolution Scanning Auger Microscopic Investigation of Intergranular Fracture in as-Quenched Fe-12Mn

Previous research in this laboratory led to the conclusion that the low temperature intergranular fracture mode in Fe-Mn alloys is microstructurally determined, and does not require metalloid segregation or other chemical contamination. That conclusion was tested in the present investigation, which used high resolution scanning Auger microscopy to study the intergranular fracture surfaces. The fracture mode at liquid nitrogen temperature was found to be intergranular fracture whenever the alloy was quenched from the austenite field, irrespective of the austenization time or temperature. High resolution chemical analyses of the intergranular fracture surfaces failed to reveal any consistent segregation of P, S, 0, or N. The occasional appearance of sulfur or oxygen on the fracture surface was found to be due to a low density precipitation of MnS and MnO{sub 2} along the prior austenite grain boundaries. Excepting these dispersed precipitates, there was no evidence of manganese enrichment of the prior austenite grain boundaries. A slight segregation of carbon was found along the grain boundaries, but does not appear to be implicated in the tendency toward intergranular fracture. The present results hence reinforce the conclusion that the low temperature intergranular fracture of Fe-12Mn is microstructurally determined.
Date: February 1, 1981
Creator: Lee, H. J. & Morris, J. W., Jr.
System: The UNT Digital Library
IS THERE A CONTINUUM AMBIGUITY FOR ELASTIC {pi}N AMPLITUDES? (open access)

IS THERE A CONTINUUM AMBIGUITY FOR ELASTIC {pi}N AMPLITUDES?

The continuum ambiguity is defined as a phase factor not determined by those amplitude zeros near the physical region that can be directly deduced from the data; such a factor may be approximated by a polynomial whose zeros are far from the physical region. A study of recent TIN partial wave analysis (CUTKOSKY76 and HOHLER78) reveals that such a phase is either null or negligeable; CUTKOSKY76' s amplitude is found similar to that of a partial wave analysis based on Barrelet zeros. We give general arguments based on the notion of "peripheral resonances" to explain this situation. Our arguments imply that Atkinson"s {pi}{sup +}p "continuous ambiguity" is not relevant to the reliability of Barrelet-zero amplitude analysis.
Date: December 1, 1981
Creator: Chew, D. M. & Ely, R. P.
System: The UNT Digital Library
A RECIPROCATING SOLAR HEATED ENGINE UTILIZING DIRECT ABSORPTION BY SMALL PARTICLES (open access)

A RECIPROCATING SOLAR HEATED ENGINE UTILIZING DIRECT ABSORPTION BY SMALL PARTICLES

A new type of reciprocating solar engine utilizing small particles to absorb concentrated sunlight directly within the cylinders is described. The engine operates by drawing an air particle mixture into the cylinder, compressing the mixture, opening an optical valve to allow concentrated sunlight to enter through a window in the top of the cylinder head, absorbing the solar flux with the particles, and converting the heat trapped by the air-particle mixture into mechanical energy with the downward stroke of piston. It differs from other gas driven heat engines using solar energy in three main respects. First, the radiant flux is deposited directly in the working fluid inside the cylinder; second, the heat is directed to the appropriate cylinder by controlling the solar flux by an optical system; third, the gas is heated during a significant portion of the compression stroke. The thermodynamic efficiency of the engine is calculated using an analytical model and is compared to several other engine cycles of interest.
Date: May 1, 1981
Creator: Hull, Patricia G. & Hunt, Arlon J.
System: The UNT Digital Library
Thermal Gradient Migration of Brine Inclusions in Synthetic Alkali Halide Single Crystals (open access)

Thermal Gradient Migration of Brine Inclusions in Synthetic Alkali Halide Single Crystals

An apparatus consisting of an optical microscope with a hot stage attachment capable of simultaneously non-uniformly heating and mechanically loading small single crystals of salt was used to measure the velocities of all-liquid inclusions in NaCl and KCl specimens under various conditions of temperature, temperature gradient, and uniaxial stress. The rate-controlling elementary step in the migration of the inclusions was found to be associated with interfacial processes, probably dissolution of the hot face. Dislocations are required for this step to take place. The small number of dislocation intersections with small inclusions in nearly perfect crystals causes substantial variations in the velocity, a sensitivity of the velocity to mechanical loading of the crystal, and a velocity which varies approximately as the square of the temperature gradient.
Date: January 1, 1981
Creator: Olander, D.R.; Machiels, A.J.; Balooch, M. & Yagnik, S.
System: The UNT Digital Library
The Theory of Uranium Enrichment by the Gas Centrifuge (open access)

The Theory of Uranium Enrichment by the Gas Centrifuge

Onsager's analysis of the hydrodynamics of fluid circulation in the boundary layer on the rotor wall of a gas centrifuge is reviewed. The description of the flow in the boundary layers on the top and bottom end caps due to Carrier and Maslen is summarized. The method developed by Wood and Morton of coupling the flow models in the rotor wall and end cap boundary layers to complete the hydrodynamic analysis of the centrifuge is presented. Mechanical and thermal methods of driving the internal gas circulation are described. The isotope enrichment which results from the superposition of the elementary separation effect due to the centrifugal field in the gas and its internal circulation is analyzed by the Onsager-Cohen theory. The performance function representing the optimized separative power of a centrifuge as a function of throughput and cut is calculated for several simplified internal flow models. The use of asymmetric ideal cascades to exploit the distinctive features of centrifuge performance functions is illustrated.
Date: March 1, 1981
Creator: Olander, Donald R.
System: The UNT Digital Library
AN APPLICATION OF FUZZY SET THEORY TO DATA DISPLAY (open access)

AN APPLICATION OF FUZZY SET THEORY TO DATA DISPLAY

Categorization supports decision making, letting an analyst look at data from different perspectives and different levels of detail. An approach to data analysis is described in which membership in subjectively defined categories is modeled by the fuzzy nature of color categories and presented via computer graphics for visual inspection by the analyst.
Date: February 1, 1981
Creator: Benson, William H.
System: The UNT Digital Library
SYNTHESIS, CHARACTERIZATION, AND STRUCTURE OF A URANYL COMPLEX WITH A DISULFIDE LIGAND, BIS(DI-n-PROPYLAMMONIUM) DISULFIDOBIS (DI-n-PROPYLMONOTHIOCARBAMATO) DIOXOURANATE(VI) (open access)

SYNTHESIS, CHARACTERIZATION, AND STRUCTURE OF A URANYL COMPLEX WITH A DISULFIDE LIGAND, BIS(DI-n-PROPYLAMMONIUM) DISULFIDOBIS (DI-n-PROPYLMONOTHIOCARBAMATO) DIOXOURANATE(VI)

Olive-green crystals of the title compound, [({underline n}-C{sub 3}H{sub 7}){sub 2}NH{sub 2}{sup +}]{sub 2} [UO(({underline n}-C{sub 3}H{sub 7}){sub 2}NCOS){sub 2}(S{sub 2}){sup -2}, are orthorhombic, space group Pcan, with {underline a}= 15.326(6) {Angstrom}, {underline b} = 17.474(6) {Angstrom}, {underline C} = 14.728(6) {Angstrom}, and Z = 4, (d{sub X} = 1.45 g/cm{sup 3}). For 1833 data, I >{sigma}, R = 0.052, and R{sub w} = 0.069. The structure was revealed by single-crystal x-ray diffraction studies to consist of [(n-C{sub 3}H{sub 7}){sub 2}NH{sub 2}]+ cations and [UO{sub 2}(({underline n|-C{sub 3}H{sub 7}){sub 2}NCOS){sub 2}(S{sub 2}){sup -2} anions with the uranium atom at the center of an irregular hexagonal bipyramid. The uranyl oxygen atoms occupy the axial positions. The equatorial coordination plane contains the disulfide (S{sub 2}{sup -2}) group bonded in a "side-on" fashion, and two oxygen and two sulfur donor atoms from the monothiocarbamate ligands. Interatomic distances are S-S = 2.05(1) {Angstrom}, U-S= 2.714(3) {Angstrom} (disulfide); U-S= 2.871(3) {Angstrom} and U-O = 2.46(1) {Angstrom} (thiocarbamate); U-O = 1.81(1) {Angstrom} (uranyl), The nitrogen atom in the dipropylammonium cation is hydrogen bonded to the uranyl oxgyen atoms,
Date: May 1, 1981
Creator: Perry, Dale L.; Zalkin, Allan; Ruben, Helena & Templeton, David H.
System: The UNT Digital Library
DETAILED LOOP MODEL (DLM) ANALYSIS OF LIQUID SOLAR THERMOSIPHONS WITH HEAT EXCHANGERS (open access)

DETAILED LOOP MODEL (DLM) ANALYSIS OF LIQUID SOLAR THERMOSIPHONS WITH HEAT EXCHANGERS

An analytical Detailed Loop Model (DLM) has been developed to analyze the performance of solar thermosiphon water heaters with heat exchangers in storage tanks. The model has been used to study the performance of thermosiphons as a function of heat exchanger characteristics, heat transfer fluids, flow resistances, tank stratification, and tank elevation relative to the collector. The results indicate that good performance can be attained with these systems compared to thermosiphons without heat exchangers.
Date: June 1, 1981
Creator: Mertol, A.; Place, W.; Webster, T. & Greif, R.
System: The UNT Digital Library
Resonance production by two-photon interactions at SPEAR (open access)

Resonance production by two-photon interactions at SPEAR

Two-photon interactions have been studied with the SLAC-LBL Mark II magnetic detector at SPEAR. The cross section for {eta}' production by the reaction e{sup +}e{sup -} {yields} e{sup +}e{sup -}{eta}' has been measured at beam energies from 2.0 GeV to 3.7 GeV. The radiative width {Lambda}{sub {gamma}{gamma}}({eta}') has been determined to be 5.8 {+-} 1.1 keV ({+-}20% systematic uncertainty). Upper limits on the radiative widths of the f(1270), A{sub 2}(1310) and f'(1515) tensor mesons have been determined. A search has been made for production of the E(1420) by {gamma}{gamma} collisions, but no signal is observed.
Date: June 1, 1981
Creator: Jenni, P.; Burke, D. L.; Telnov, V.; Alam, M. S.; Boyarski, A. M.; Breidenbach, M. et al.
System: The UNT Digital Library
EXPERIMENTAL RESULTS ON TRAPPING A GUN PLASMA IN TORMAC P-l (open access)

EXPERIMENTAL RESULTS ON TRAPPING A GUN PLASMA IN TORMAC P-l

A start-up scheme for producing a plasma in the biscusp field configuration of TORMAC which involves the radial injection and trapping of a toroidal gun plasma is described. The peloidal field of the external cusp coils acts as a barrier to the outward travel of the plasma ring. Interferometry and magnetic probe measurements observed the stopping of the expanding plasma ring which has a velocity of 17 cm/{micro}sec. Once stopped, the fields are arranged to hold the plasma in a magnetic well. Interferometry measurements observed a well defined outer boundary remaining stationary during the 20 {micro}sec of the measurement. The inner boundary was also in evidence as shown particularly by the particle flux distribution emanating from the cusp region. The indications are that a sheath exists having a width of 1 to 1.5 ion gyro radii in the poloidial field. Measurements of Thomson and interferometry give a T{sub e} of 15eV, a 15 {micro}sec density decay time, and a 5 {micro}sec energy decay time. These results show that this injection and trapping method is successful, and thus a higher gun plasma energy combined with a flux conserving barrier may lead to higher temperatures for testing containment in TORMAC.
Date: July 1, 1981
Creator: Pincosy, P. A.; Myers, B. R.; Levine, M. A.; Feinberg, B.; Niland, R. A. & Soroka, L.
System: The UNT Digital Library
HIGH CURRENT D- PRODUCTION BY CHARGE EXCHANGE IN SODIUM (open access)

HIGH CURRENT D- PRODUCTION BY CHARGE EXCHANGE IN SODIUM

A beam of D{sup -} ions has been produced at 7-13 keV, with currents up to 2.2 {angstrom}, using charge exchange in sodium vapor. The beam profile is bi-Gaussian with angular divergence 0.7{sup o} x 2.8{sup o} and peak current density 15 mA/cm{sup 2}. The characteristics of the beam are in excellent agreement with predictions based on atomic cross sections. The sodium vapor target is formed by a jet directed across the beam. The sodium density drops rapidly in the beamline downstream from the charge exchange region, decreasing three orders of magnitude in 15 cm. Measurement and analysis of the plasma accompanying the beam demonstrate that plasma densities nearly equal to the beam density are obtained 1 m from the charge exchange medium. The plasma produced in the sodium is thus well confined to the charge exchange region and does not propagate along the beam.
Date: February 1, 1981
Creator: Hooper, E.B.; Poulsen, P. & Pincosy, P.A.
System: The UNT Digital Library
Interpretation of Shallow Electrical Features From Electromagnetic and Magnetotelluric Surveys at Mount Hood, Oregon (open access)

Interpretation of Shallow Electrical Features From Electromagnetic and Magnetotelluric Surveys at Mount Hood, Oregon

A magnetotelluric survey, with a reference magnetometer for noise cancellation, was conducted at accessible locations around Mount Hood, Oregon. Thirty-eight tensor magnetotelluric (MT) and remote telluric stations were set up in clusters around the volcano except for the northwest quadrant, a wilderness area. Because of limited access, station locations were restricted to elevations below 1829 m, or no closer than 5 km from the 3424-m summit. On the basis of the MT results, three areas were later investigated in more detail using a large-moment, controlled-source electromagnetic (EM) system developed at Lawrence Berkeley Laboratory and the University of California at Berkeley. One-dimensional interpretations of EM and MT data on the northeast flank of the mountain near the Cloud Cap eruptive center and on the south flank near Timberline Lodge show a similar subsurface resistivity pattern: a resistive surface layer 400-700 m thick, underlain by a conductive layer with variable thickness and resistivity of <20 ohm m. It is speculated that the surface layer consists of volcanics partially saturated with cold meteoric water. The underlying conductive zone is presumed to be volcanics saturated with water heated within the region of the central conduit and, possibly, at the Cloud Cap side vent. This …
Date: April 1, 1981
Creator: Goldstein, N. E.; Mozley, E. & Wilt, M.
System: The UNT Digital Library
Optical Properties of Molecules Chemisorbed on the Ni(111) Surface (open access)

Optical Properties of Molecules Chemisorbed on the Ni(111) Surface

The adsorption of a series of molecules on Ni(111) is studied by UV/visible spectroscopic ellipsometry. The spectra were analyzed within a simple dielectric model. Chemisorption of molecules on the Ni(111) surface produces a peak in the overlayer optical response at 4.2 eV. This absorption peak is attributed to the selective enhancement of bulk interband excitations resulting from perturbations of the metal orbitals upon chemisorption.
Date: August 1, 1981
Creator: Robota, H. J.; Whitmore, P. M. & Harris, C. B.
System: The UNT Digital Library
JETS OF NUCLEAR MATTER FROM HIGH ENERGY HEAVY ION COLLISIONS (open access)

JETS OF NUCLEAR MATTER FROM HIGH ENERGY HEAVY ION COLLISIONS

The nuclear fluid dynamical model with final thermal breakup is used to study the reactions {sup 20}Ne + {sup 238}U and {sup 40}Ar + {sup 40}Ca at E{sub LAB} = 390 MeV/n. The calculated double differential cross sections d{sup 2}{sigma}/d{Omega}dE are in agreement with recent experimental data. However, it is shown that the azimuthal dependence of the triple differential distributions d{sup 3}{sigma}/dEdcos{theta}d{phi}, to be obtained from 4{pi} exclusive experiments with single event analysis, can yield considerably deeper insight into the collision process and allow for snapshots of the reactions. Strongly correlated jets of nuclear matter are predicted.
Date: February 1, 1981
Creator: Stocker, H.; Csernai, L.P.; Graebner, G.; Buchwald, G.; Kruse, H.; Cusson, R.Y. et al.
System: The UNT Digital Library
Photoelectron Angular Distributions of H{sub 2}O (open access)

Photoelectron Angular Distributions of H{sub 2}O

The partial cross-section and asymmetry parameters of the {sup 2}B{sub 1}, {sup 2}A{sub 1} and {sup 2}B{sub 2} ionic states of H{sub 2}O{sup +} have been measured at photon energies of 18-31 eV, by time-of-flight photoelectron spectroscopy using synchrotron radiation. The atomic character of the molecular orbitals is discussed in the interpretation of similarities and differences between the measurements for these states. Other synchrotron radiation data, resonance line measurements, and (e,2e) dipole results are included. A multiple-scattering X{sub {alpha}} (MSX{sub {alpha}}) calculation and a ground-state inversion method calculation are in good agreement with our cross-section measurements. There is excellent agreement between experimental asymmetry parameters and those computed from the MSX{sub {alpha}} method. Stieltjes-Tchebycheff imaging model calculations suggest the presence of resonant channels. This may be the origin of weak resonance structure present in the measurements.
Date: August 1, 1981
Creator: Truesdale, C. M.; Southworth, S.; Kobrin, P. H.; Lindle, D. W.; Thornton, G. & Shirley, D. A.
System: The UNT Digital Library