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Day
Radioactive waste transportation systems analysis and program plan
The objective of the Transportation/Logistics Study is to ensure the availability of a viable system for transporting the wastes to a federal repository in 1985. In order to accomplish this objective, a systems analysis of waste transportation has been directed by ORNL to determine the problems that must be solved and to develop a program plan that identifies which problems must first be pursued. To facilitate this overall approach and to provide for short- and long-range waste management, logistics models have been developed to determine the transportation fleet requirements and costs. Results of the study are described in this report.
Date:
March 1, 1978
Creator:
Shappert, L. B.; Joy, D. S. & Heiskell, M. M.
Object Type:
Report
System:
The UNT Digital Library
Anomalous rf magnetoresistance in copper at 4/degree/K
We have measured the effect of a magnetic field on the surface resistance of polycrystalline Cu at f = 1.2 GHz and at 4.4/degree/K; under these conditions the surface resistance is well into the anomalous skin effect regime but has not reached its limiting value. We find that the transverse and longitudinal magnetoresistance are an order of magnitude smaller than the DC magnetoresistance and depend quadratically on the field. At low fields we observe a decrease in surface resistance with increasing field which can be interpreted as a size effect of the TF surface current. 17 refs., 4 figs., 1 tab.
Date:
March 1, 1988
Creator:
Halama, H. J.; Prodell, A. G.; Rogers, J. T.; De Panfilis, S.; Melissinos, A. C.; Moskowitz, B. E. et al.
Object Type:
Report
System:
The UNT Digital Library
Development of improved cathodes for solid oxide fuel cells
The University of Missouri-Rolla conducted a 17 month research program focused on the development and evaluation of improved cathode materials for solid oxide fuel cells (SOFC). The objectives of this program were: (1) the development of cathode materials of improved stability in reducing environments; and (2) the development of cathode materials with improved electrical conductivity. The program was successful in identifying some potential candidate materials: Air sinterable (La,Ca)(Cr,Co)O{sub 3} compositions were developed and found to be more stable than La{sub .8}Sr{sub .2}MnO{sub 3} towards reduction. Their conductivity at 1000{degrees}C ranged between 30 to 60 S/cm. Compositions within the (Y,Ca)(Cr,Co,Mn)O{sub 3} system were developed and found to have higher electrical conductivity than La{sub .8}Sr{sub .2}MnO{sub 3} and preliminary results suggest that their stability towards reduction is superior.
Date:
March 1, 1991
Creator:
Anderson, H.U.
Object Type:
Report
System:
The UNT Digital Library
Process feasibility study in support of silicon material, Task I. Quarterly technical progress report (XVIII), December 1, 1979-February 29, 1980
Analyses of process system properties were continued for important chemical materials involved in the several processes under consideration for semiconductor and solar cell grade silicon production. Major activities were devoted to physical, thermodynamic and transport property data for silicon. Property data are reported for vapor pressure heat of vaporization, heat of sublimation, liquid heat capacity and solid heat capacity as a function of temperature to permit rapid usage in engineering. Chemical engineering analysis of the HSC process (Hemlock Semiconductor Corporation) for production of silicon was initiated. The process is based on hydrogen reduction of dichlorosilane (DCS) to produce the polysilicon. The chemical vapor deposition reaction for DCS is faster in rate than the conventional process route which utilizes trichlorosilane (TCS) as the silicon raw material. Status and progress are reported for primary activities of base case conditions (30%), reaction chemistry (25%) and process flow diagram (20%). Discussions with HSC and construction of a process flow diagram are in progress. Preliminary economic analysis of the BCL process (case B) was completed. Cost analysis results are presented based on a preliminary process design of a plant to produce 1000 metric tons/year of silicon. Fixed capital investment for the plant is $14.35 million …
Date:
March 1, 1980
Creator:
Yaws, C.L. & Li, K.Y.
Object Type:
Report
System:
The UNT Digital Library
Analysis of standards for energy-efficient motors
This analysis does not lead to a clear conclusion regarding the effectiveness of standards for energy efficient motors if effectiveness is based on a benefit-cost ratio criteria. Two alternative assumptions were made regarding the appropriate measure of the costs to the private sector. In the first case it was assumed that private sector users have no biases and expect rates of return on investment that represent their true opportunity cost of capital. Under this assumption the benefit-cost ratio is .65, that is, for every dollar of cost incurred, the associated benefit is 65 cents. The alternative assumption is tha the private sector under values energy conservation investments. Under this assumption, the benfit-cost ratio of the standards program was 1.35. For every dollar spent, $1.35 is returned to society, because the standards force private sector users to correct their biases and therefore allocate capital more productively.
Date:
March 1, 1981
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Dynamic shear behavior of alumina-filled epoxy
Thin-walled tubular specimens of alumina-filled epoxy were loaded in torsion at a strain rate of approximately 10/sup 3/ s/sup -1/ using a stored-torque Kolsky bar. In addition to measuring the time resolved shear stress and shear strain in the specimen, the axial stress generated by the dilation of the material during shear deformation was also obtained as a function of time. Tests were conducted at room temperature and at -60/sup 0/C. At room temperature, a moderate amount of plastic deformation occurred before failure. Material dilation was associated with the plastic flow. At -60/sup 0/C, there was a marked increase in failure stress over the failure stress at room temperature. However, little or no plastic deformation or dilation occurred before failure.
Date:
March 1, 1982
Creator:
Costin, L.S.
Object Type:
Report
System:
The UNT Digital Library
A survey of air flow models for multizone structures
Air flow models are used to simulate the rates of incoming and outgoing air flows for a building with known leakage under given weather and shielding conditions. Additional information about the flow paths and air-mass flows inside the building can only by using multizone air flow models. In order to obtain more information on multizone air flow models, a literature review was performed in 1984. A second literature review and a questionnaire survey performed in 1989, revealed the existence of 50 multizone air flow models, all developed since 1966, two of which are still under development. All these programs use similar flow equations for crack flow but differ in the versatility to describe the full range of flow phenomena and the algorithm provided for solving the set of nonlinear equations. This literature review was found that newer models are able to describe and simulate the ventilation systems and interrelation of mechanical and natural ventilation. 27 refs., 2 figs., 1 tab.
Date:
March 1, 1991
Creator:
Feustel, H.E. & Dieris, J.
Object Type:
Report
System:
The UNT Digital Library
A numerical study of Rayleigh-Taylor instability in aluminum and steel plates
The SCRAM code is applied to the study of Rayleigh-Taylor instability in metal plates, and comparisons of these computer results are made with experimental data for 1100-O aluminum, 6061-T6 aluminum and 304 stainless steel. Various models for the pressure, temperature, and strain-rate dependencies of the flow stress are compared in the computer calculations. The coefficients that are required in these models to give good agreement with the experimental results are generally close to values that were determined from previous experimental comparisons. The sensitivity of the computed results to modeling parameters, to variations in the hardening modulus, and to the amplitude and wavelength of the perturbations in the plate surface is examined. Very little growth in amplitude occurs if either the initial amplitude or the wavelength is sufficiently small. The growth rate increases monotonically with increasing initial amplitude. There appears to exist a wavelength of maximum growth, such that the growth rate increases rapidly with wavelength up to this wavelength, but then decreases slowly as the wavelength is further increased.
Date:
March 1, 1988
Creator:
Daly, B.J.
Object Type:
Report
System:
The UNT Digital Library
Assessment of lamellar tearing
Information on lamellar tearing is summarized and related to proposed ASME Code requirements. Lamellar tearing is characterized as a complex phenomenon related to poor short transverse ductility and through-thickness strain. The material, welding, and design variables that affect lamellar tearing are shown to be complex and interrelated. The commonly reported tests for assessing material susceptibility are described, with the controversy over their validity being carefully detailed. Although the use of a nondestructive test such as ultrasonic examination is most desirable, a widely applicable test method does not appear to be available. Of the destructive tests, the short transverse tensile reduction-of-area currently offers the most applicable means of assessing material susceptibility. However, because of the importance of matrix toughness, the short transverse Charpy V-notch test should be considered for use as an additional test if acceptance limits are developed. The ultrasonic detection of lamellar tears is susceptible to interpretation errors, which can make it overly conservative and lead to unnecessary repairs. The repair of tears is described as costly, difficult, and sometimes ineffective. Current design requirements appear to preclude any failures during static and fatigue service loads. However, without improvement of short transverse ductility, certain dynamic service loads could cause lamellar …
Date:
March 1, 1978
Creator:
McEnerney, J.W.
Object Type:
Report
System:
The UNT Digital Library
Pion scattering to 8/sup -/ stretched states in /sup 60/Ni
Using the Energetic Pion Channel and Spectrometer at the Los Alamos Meson Physics Facility, differential cross sections for pion scattering were measured for ten previously known J/sup ..pi../ = 8/sup /minus// stretched states in /sup 60/Ni. A possible new pure isoscalar stretched state was also found. The data were taken near the /DELTA//sub 3,3/-resonance using 162 MeV incident pions and scattering angles of 65/degree/, 80/degree/, and 90/degree/ for ..pi../sup +/ and 65/degree/ and 80/degree/ for ..pi../sup /minus//. The analysis of the /sup 60/Ni data found that the use of Woods-Saxon wave functions in the theoretical calculations gave much better agreement with data than the use of the usual harmonic oscillator wave functions. The WS theory gave better predictions of: the angle at which the ..pi../sup /minus// and ..pi../sup +/ angular distributions are maximum, the ratios of ..pi../sup /minus// to ..pi../sup +/ cross sections for pure isovector states (which were much larger than unity), and the absolute size of the cross sections for all states (so that the normalization factor necessary to arrive at agreement of theory with data was closer to unity). The theoretical calculations used the distorted wave impulse approximation, including new methods for unbound states. The sensitivities of …
Date:
March 1, 1988
Creator:
Clausen, B.L.
Object Type:
Report
System:
The UNT Digital Library
Conceptual design and systems analysis of photovoltaic power systems. Volume II. Systems. Revised final report
Conceptual designs were made and analyses were performed on three types of solar photovoltaic power systems. Included were Residential (1--10 kW), Intermediate (0.1--10 MW), and Central (50--1000 MW) Power Systems to be installed in the 1985 to 2000 time period. Detailed descriptions of each of the three systems studied, descriptions of the necessary subsystems, and discussions of the interfaces between them are presented. Included also are descriptions of system performance and system cost used to perform an economic analysis which assesses the value of each system.
Date:
March 1, 1977
Creator:
Pittman, P.F.
Object Type:
Report
System:
The UNT Digital Library
Nuclear mass formula with a neutron skin degree of freedom and finite-range model for the surface energy
We study the possibility of extending the model used by Moeller and Nix in 1980 to calculate nuclear masses and fission barriers for nuclei throughout the periodic system, to describe compressibility effects and the existence of a neutron skin. 9 references. (WHK)
Date:
March 1, 1984
Creator:
Moeller, P. & Myers, W.D.
Object Type:
Article
System:
The UNT Digital Library
Interaction of impurity ions with a weakly non-Maxwellian simple hydrogenic plasma. [None]
The average acceleration of an ensemble of /open quotes/test particles/close quotes/ in a plasma is called the /open quotes/dynamical friction/close quotes/; the average rate at which their velocity vectors spread out in velocity-space diffusion-rate tensor. These quantities are derived for impurity ions intereacting with a weakly non-Maxwellian simple hydrogenic plasma. The distribution functions for the plasma ions and electrons are written explicitly.
Date:
March 1, 1988
Creator:
Terry, W.K.
Object Type:
Report
System:
The UNT Digital Library
Cost of splitting in Monte Carlo transport
In a simple transport problem designed to estimate transmission through a plane slab of x free paths by Monte Carlo methods, it is shown that m-splitting (m > or = 2) does not pay unless exp(x) > m(m + 3)/(m - 1). In such a case, the minimum total cost in terms of machine time is obtained as a function of m, and the optimal value of m is determined.
Date:
March 1, 1978
Creator:
Everett, C.J. & Cashwell, E.D.
Object Type:
Report
System:
The UNT Digital Library
(Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)
This report contains information related to the sampling and chemical analysis of ground water at the Wright-Patterson Air Force Base. It is part of a field investigation of ground water contamination.
Date:
March 1, 1992
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Detection of charged particles in thick hydrogenated amorphous silicon layers
We show our results in detecting particles of various linear energy transfer, including minimum ionizing electrons from a Sr-90 source with 5 to 12 micron thick n-i-p and p-i-n diodes. We measured W ( average energy to produce one electron-hole pair) using 17keV filtered xray pulses with a result W = 6.0 /+-/ 0.2eV. This is consistent with the expected value for a semiconductor with band gap of 1.7 to 1.9eV. With heavily ionizing particles such as 6 MeV alphas and 1 to 2 MeV protons, there was some loss of signal due to recombination in the particle track. The minimum ionizing electrons showed no sign of recombination. Applications to pixel and strip detectors for physics experiments and medical imaging will be discussed. 7 refs., 8 figs.
Date:
March 1, 1988
Creator:
Fujieda, I.; Cho, G.; Kaplan, S. N.; Perez-Mendez, V.; Qureshi, S.; Ward, W. et al.
Object Type:
Article
System:
The UNT Digital Library
Depth distributions of low energy deuterium implantations in (110) tungsten: a theoretical model
The depth distributions of 80 eV D/sup +/ implants in (110) W have recently been measured by field desorption microscopy. Prominent structure, consisting of seven major and several minor peaks, is observed in the measured distributions. This contrasts with conventional implantation theory which predicts two peaks, one for the channeled D/sup +/ and one for the nonchanneled D/sup +/. The observed structure is explained in the present report by a model which ascribes the various peaks to D/sup +/ groups which have been scattered into planar channels by the surface impurities. The model allows a determination of D/sup +/ stopping powers in the various planar channels and the stopping power of C and O impurities which recoil down the (110) axis. The model suggests that surface location of the impurities as well as their elastic scattering cross section for D/sup +/ projectiles could be extracted from more elaborate calculations and experiments.
Date:
March 1, 1978
Creator:
Brice, D.K.
Object Type:
Report
System:
The UNT Digital Library
Cogeneration Handbook for the Pulp and Paper Industry. [Contains Glossary]
The decision of whether to cogenerate involves several considerations, including technical, economic, environmental, legal, and regulatory issues. Each of these issues is addressed separately in this handbook. In addition, a chapter is included on preparing a three-phase work statement, which is needed to guide the design of a cogeneration system. In addition, an annotated bibliography and a glossary of terminology are provided. Appendix A provides an energy-use profile of the pulp and paper industry. Appendices B and O provide specific information that will be called out in subsequent chapters.
Date:
March 1, 1984
Creator:
Griffin, E. A.; Moore, N. L.; Fassbender, L. L.; Garrett-Price, B. A.; Fassbender, A. G.; Eakin, D. E. et al.
Object Type:
Report
System:
The UNT Digital Library
Feasibility Studies of in-Situ Coal Gasification in the Warrior Coal Field. Quarterly Report
Laboratory studies on a research combustor were used in an attempt to determine the length of oxidation and reduction zones. Unfortunately the buoyant effects of the heated gases caused the burn to proceed along the upper portion of the horizontal combustor. This made the interpretation of uncertain value. Methods of measuring the thermal conductivity and chemical reactivity of coke are discussed. A bibliography of the physical and chemical properties of coke is appended. (LTN)
Date:
March 1, 1979
Creator:
Douglas, George W. & McKinley, Marvin D.
Object Type:
Report
System:
The UNT Digital Library
Fault activity and seismicity near the Los Alamos Scientific Laboratory geothermal test site, Jemez Mountains, New Mexico
None
Date:
March 1, 1975
Creator:
Slemmons, D.B.
Object Type:
Report
System:
The UNT Digital Library
Critical Technology List update. Final technical report
ICRC has reviewed and updated its List of critical technology. The List comprises all proposed SRC-I Demonstration Plant equipment whose use has been determined to involve some degree of potential safety, performance, or environmental risk. ICRC has subjected equipment on the Critical Technology c to special technical review to ensure the highest possible level of quality and lowest cost commensurate with acceptable overall risks. Equipment or equipment systems still considered to be high risk are the following: Coal Slurry/Hot Oil Heat Exchangers, Coal Slurry Heaters, Second-Stage Feed Heaters, Vacuum Tower Heater, Vacuum Column, SRC/Light SRC Stripper - CSD, Severe Service Valves, Wastewater Reuse System, and the Solid Waste Disposal System. Equipment systems or pieces of equipment that have been downgraded to a lower risk category are the following: Coal Weigh-Feed System, Coal Slurry Dissolvers, Coal Dissolver Effluent Separator, and LC-Fining Reactors. Finally, ICRC has determined that many types of equipment are no longer Critical Technology, and has therefore removed them from the List.
Date:
March 1, 1983
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Spectra in the 60 )angstrom) to 345 )angstrom) wavelength region of elements injected into the PLT tokamak
High resolution spectra of the elements Fe, Ni, Zn, Ge, Se, and Mo injected into the PLT tokamak were recorded by the 2-meter Schwob-Fraenkel soft X-ray multichannel spectrometer (SOXMOS). Spectra were recorded every 50 ms during the time before and after injection. The spectral lines of the injected element were very strong in the spectrum recorded immedately after injection, and the transition in the injected element were easily distinguished from the transitions in te intrinsic elements (C, O, Ti, Cr, Fe, and Ni). An accurate wavelength scale was established using well-known reference transitions in the intrinsic elements. The spectra recorded just prior to injection were substracted from the spectra recorded after injection, and the resulting spectrum was composed almost entirely of transitions from the injected element. A large number of ..delta..n + 0 transitions between the ground and the first excited configurations in the Li I through K I isoelectronic sequences of the injected elements were identified in the wavelength region 60 )angstrom) to 345 )angstrom). 33 refs., 5 figs., 1 tab.
Date:
March 1, 1988
Creator:
Wouters, A.; Schwob, J.L.; Suckewer, S.; Seely, J.F.; Feldman, U. & Dave, J.H.
Object Type:
Report
System:
The UNT Digital Library
Semiclassical methods in chemical dynamics
A general semiclassical (multidimensional WKB-type) approximation to quantum mechanics is reviewed. The principal feature of the approach is that it is able to incorporate the exact classical mechanics of the system and also the quantum principle of superposition. Applications to inelastic and reactive scattering, and to statistical mechanics and reaction rates are discussed. 13 refs.
Date:
March 1, 1985
Creator:
Miller, W. H.
Object Type:
Article
System:
The UNT Digital Library
Recent results from studies of non-gaseous fission products with TRISTAN II
A new in-beam target ion-source combination has been installed at the TRISTAN isotope separator facility. Mass separated beams of nongaseous fission products are now available for study. Studies of levels in even-even Cd and Sn nuclei populated through the decay of Ag and In fission products are described, and an evaluation of possibilities for future research is made.
Date:
March 1, 1978
Creator:
Hill, J. C.
Object Type:
Report
System:
The UNT Digital Library