Ambient pressure characteristics of heavy-fermion compounds, such as the ratio of the low temperature magnetic susceptibility to the electronic specific heat coefficient {gamma} and a simple relationship between the T{sup 2}-coefficient of resistivity and {gamma}{sup 2}, suggest that a single-energy scale T{sub o} dictates the physics of these materials. Such is the case for Kondo-impurity systems to which heavy-fermions are related. We consider the consequences of assuming that the electronic free energy is given by a universal function of T/T{sub o} (V) where V is the molar volume. We show that volume-dependent magnetic susceptibility, specific heat and electrical resistivity of some heavy-fermion compounds scale as T/T{sub o} (V), at least over a range in pressures and temperatures. A further consequence of the principle assumption is that Gruneisen parameters defined as - {partial_derivative}{ell}nX/{partial_derivative}nV, where X is some physical property, should be identical for all properties and equal to that determined from electronic contributions to the volume- thermal expansion coefficient and specific heat. In several materials, this equality holds, at least approximately. Although evidence is found for single-energy scaling in heavy-fermion materials, we cannot conclude unambiguously that the basic assumption is correct in detail.

A liquid metal MHD (Magnetohydrodynamic)/heat transfer test was conducted at the ALEX (Argonne Liquid Metal Experiment) facility of ANL (Argonne National Laboratory), jointly between ANL and NIIEFA (Efremov Institute). The test section was a rectangular slotted channel geometry (meaning the channel has a high aspect ratio, in this case 10:1, and the long side is parallel to the applied magnetic field). Isothermal and heat transfer data were collected. A heat flux of {approximately}9 W/cm{sup 2} was applied to the top horizontal surface (the long side) of the test section. Hartmann Numbers to 1050 (2 Tesla), interaction parameters to 9 {times} 10{sup 3}, Peclet numbers of 10--200, based on the half-width of the small dimension (7mm), and velocities of 1--75 cm/sec. were achieved. The working fluid was NaK (sodium potassium eutectic). All four interior walls were bare, 300-series stainless steel, conducting walls.

A collaborative program has been initiated to measure helium (He) transport and exhaust on DIII-D in L-mode, ELM-free H-mode, and ELMing H-mode. These diverted plasmas operating in enhanced confinement regimes should provide valuable information for the International Thermonuclear Experimental Reactor (ITER). To simulate the presence of He ash in DIII-D, a 50 ms He puff is injected into a DIII-D plasma, resulting in a He concentration of {approximately} 15%. The time dependence of the He density profiles in the plasma core is measured with charge-exchange recombination spectroscopy and the He spatial distribution on the diverter floor is studied with an impurity monitor array. The dependence of core transport diffusivities as a function of ELM frequency have been studied and the first demonstration made of He exhaust from an H-mode plasma in a diverted tokamak. The exhaust rate of He from these ELMing H-mode plasmas appears to be within the acceptable range for a fusion reactor, like ITER, based on a measured value of {tau}*{sub He}/{tau}E {approx}14.

Theoretical investigation has been made on double excitation processes of He and H{sup {minus}} by fast proton and anti-proton impact in the MeV/u-energy region. The cross sections are calculated by use of both the close-coupling and the perturbation expansion methods, and the wave functions of target atoms are generated based on the hyperspherical coordinate method. The excitation to the 2p{sup 2} {sup 1}D{sup e} state of H{sup {minus}} by anti-proton impact is dominant by about three times in comparison with that by proton impact at the incident energy of 0.1 MeV/u. The spectral shape of an ejected electron from the 2s2p {sup 1}p{sup o} state of H{sup {minus}} at the incident energy of 1.5 MeV/u is consistent with the line profile of the H{sup {minus}} photodetachment observed by Bryant et al.

Anorthite-glass films have been grown by pulsed-laser deposition on single-crystal {alpha}-Al{sub 2}O{sub 3} substrates which were pre-thinned to electron transparency. The glass films were crystallized in the transmission electron microscope (TEM), which allowed direct observation and video-recording of the crystallization process. Crystallization of these films in the TEM resulted in the formation of hexagonal and orthorhombic anorthite. The orthorhombic phase was the predominant product of glass films grown at elevated substrate temperatures and displayed strong epitaxy with the underlying substrate. In contrast, the hexagonal phase was the major constituent of films grown at ambient substrate temperature and displayed no clear epitaxy with the substrate. The difference in degree of epitaxy and phase structure may be evidence of ordering at the original glass/oxide interface.

Sandia National Laboratories (SNL) is committed to conducting its operations in an environmentally safe and sound manner. It is mandatory that activities at SNL/California comply with all applicable environmental statutes, regulations, and standards. Moreover, SNL/California continuously strives to reduce risks to employees, the public, and the environment to the lowest levels reasonably possible. To help verify effective protection of public safety and preservation of the environment, SNL/California maintains an extensive, ongoing environmental monitoring program. This program, conducted in conjunction with Lawrence Livermore National Laboratory, monitors all significant airborne and liquid effluents and the general environment in the area. This monitoring effort ensures that emission controls are effective in preventing contamination of the environment. As part of the Environmental Monitoring Program, an ambient environmental surveillance system measures the possible presence of radioactive and hazardous materials in ambient air, surface water, groundwater, sewage, soil, vegetation, and locally-produced food stuffs. The program also includes an extensive environmental dosimetry program, which measures external radiation levels around the Livermore site and nearby vicinity. This executive summary focuses on impacts to the environment and estimated radiation doses to the public from site emissions.

The TOPAZ II is a single-cell thermionic space reactor power system developed by the Russians during the period of time from {approximately}1969 to 1989. The TOPAZ II has never been flight demonstrated, but the system was extensively tested on the ground. As part of the development and test program, the response of the TOPAZ II under accident conditions was analyzed and characterized. The US TOPAZ II team has been working closely with the Russian specialists to understand the TOPAZ II system, its operational characteristics, and its response under potential accident conditions. The purpose of the technical exchange is to enable a potential launch of a TOPAZ II by the US. The information is required to integrate the system with a US spacecraft and to support the safety review process. The purpose of this paper is to provide a brief overview of the system and its response under actual and postulated accident conditions.

During the past 6 months, experiments have been conducted with the HBT-EP tokamak in order to (1) test and evaluate diagnostic systems, (2) establish basic machine operation, (3) document MHD behavior as a function of global discharge parameters, (4) investigate conditions leading to passive stabilization of MHD instabilities, and (5) quantify the external saddle coil current required for DC mode locking. In addition, the development and installation of new hardware systems has occurred. A prototype saddle coil was installed and tested. A five-position (n,m) = (1,2) external helical saddle coil was attached for mode-locking experiments. And, fabrication of the 32-channel UV tomography and the multipass Thomson scattering diagnostics have begun in preparation for installation later this year.

Research on all aspects of coal research, at least for more small scale work, involves the use of samples at the beginning of experimental work. Most research workers for smaller scale work do not collect their own coal samples, but rather order them from a group of sample suppliers. The number of suppliers meeting the major needs in the US, as well as for the world, is not very large. An examination of the shipments of samples from each of these suppliers will give an interesting insight into the general trends in volume of work in the field. The suppliers involved in this study include the Argonne Premium Coal Sample Program, the Illinois Basin Coal Sample Program, the SBN and the several groups of samples from the Pennsylvania State University Coal Sample Bank. Each of these supplies a different number of samples in varying quantities. The quantities and variety of samples is important to the individual worker in selecting a supplier. The type of work to be done frequently affects the quantities and choice of sample, which in turn affects the choice of supplier. In general these data indicate that researchers realize the advantages of acquiring samples from centralized sample …

The US Department of Energy (DOE), Morgantown Energy Technology Center (METC), is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal gas) streams of integrated gasification combined-cycle (IGCC) power systems. The programs focus on hot-gas particulate removal and desulfurization technologies that match or nearly match the temperatures and pressures of the gasifier, cleanup system, and power generator. The purpose is to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs. Hot-gas desulfurization research has focused on regenerable mixed-metal oxide sorbents which can reduce the sulfur in coal gas to less than 20 ppmv and can be regenerated in a cyclic manner with air for multicycle operation. Zinc titanate (Zn{sub 2}TiO{sub 4} or ZnTiO{sub 3}), formed by a solid-state reaction of zinc oxide (ZnO) and titanium dioxide (TiO{sub 2}), is currently the leading sorbent. The sulfidation/regeneration cycle can be carried out in fixed-bed, moving-bed, or fluidized-bed reactor configuration, and all three types of reactors are slated for demonstration in the DOE Clean Coal Technology program. The fluidized-bed reactor configuration is most attractive because of several potential advantages including faster kinetics and the ability to handle the …

This report discusses the four CCD fiber-optic coupled detector and detector control electronics and image displays.

A program to develop and evaluate fracture methodologies for the assessment of crack-tip constraint effects on fracture toughness of reactor pressure vessel (RPV) steels has been initiated in the Heavy-Section Steel Technology (HSST) Program. The focus of studies described herein is on the evaluation of a micromechanical scaling model based on critical stressed volumes for quantifying crack-tip constraint through applications to experimental data. Data were utilized from single-edge notch bend (SENB) specimens and HSST-developed cruciform beam specimens that were tested in HSST shallow-crack and biaxial testing programs. Shallow-crack effects and far-field tensile out-of-plane biaxial loading have been identified as constraint issues that influence both fracture toughness and the extent of the toughness scatter band. Results from applications indicate that the micromechanical scaling model can be used successfully to interpret experimental data from the shallow- and deep-crack SENB specimen tests. When applied to the uniaxially and biaxially loaded cruciform specimens, the two methodologies showed some promising features, but also raised several questions concerning the interpretation of constraint conditions in the specimen based on near-tip stress fields. Crack-tip constraint analyses of the shallow-crack cruciform specimen based on near-tip stress fields. Crack-tip constraint analyses of the shallow-crack cruciform specimen subjected to uniaxial or …

Ion implantation in insulators causes modifications in the refractive-index as a result of radiation damage, phase separation, or compound formation. As a consequence, light waveguides may be formed with interesting applications in the field of optoelectronics. Recently implantation of metals ions (e.g. silver, copper, gold, lead,...) showed the possibility of small radii colloidal particles formation, in a thin surface layer of the glass substrate. These particles exhibit an electron plasmon resonance which depends on the optical constants of the implanted metal and on the refractive-index of the glass host. The non-linear optical properties of such colloids, in particular the enhancement of optical Kerr susceptibility, suggest that the, ion implantation technique may play an important role for the production of all-optical switching devices. In this paper an analysis of the state-of-the-art of the research in this field will be presented in the framework of ion implantation in glass physics and chemistry.

The Natural Excitation Technique (NExT) was used to analyze STARS launch data during first and second stage flight using telemetered acceleration data. A continuous track of modal frequencies and modal damping was acquired for the first and second elastic modes of the system during first stage flight and for the first mode during second stage flight. The results from this modal analysis of launch data allowed a final quantification of the inherent bias errors which result from ground-based modal tests. Also, NExT is shown to be an important new tool for analyzing structural dynamics data during launch.

A force reconstruction technique is being used to assess the dynamic performance of a crushable structure (a bomb nose) in both the axial (90{degree}) and slapdown (30{degree}) impact conditions. The dynamic force characteristics for the current nose design, determined from these tests, will be used to write a dynamic force specification for a new nose design that will replace the current nose. Two structures for experimentally determining the dynamic force -- deflection characteristics of the old and new noses have been designed and constructed. One structure has the same dynamic characteristics as the bomb and is being used for axial and slapdown orientations with rocket-propelled testing. The second structure has the same mass as the bomb and is being used for iterative axial testing of candidate designs with a pneumatic ram. The structural characteristics of these two structures have been determined and are presented. A force reconstruction algorithm using the Sum of Weighted Accelerations Technique (SWAT) has been developed for each of the two structures. The force reconstruction algorithms have been verified for both structures using laboratory data. The force reconstruction process and the resulting algorithms are described. Data verifying the force reconstruction algorithms is presented.

Objective was to selectively oxidize methane to C{sub 2} hydrocarbons and to oxygenates, in particular formaldehyde and methanol, in high space time yields under relatively mild reaction conditions. Results in this document are reported under the headings: methane oxidation over silica, methane oxidation over Sr/La{sub 2}O{sub 3} catalysts, and oxidative coupling of methane over sulfate-doped Sr/La{sub 2}O{sub 3} catalysts. 24 refs, 10 figs, 4 tabs.

Los Alamos National Laboratory and Institute Mexicano del Petroleo are completely a joint study of options for improving air quality in Mexico City. The US Department of Energy supported the efforts of the Los Alamos investigators, while PEMEX supported the efforts of the Mexican researchers. One of the first steps in the process was to develop an understanding of the existing air quality situation. In this context we have modified a three-dimensional, prognostic, higher order turbulence model for atmospheric circulation (HOTMAC) to treat domains which include an urbanized area. This sophisticated meteorological model is required because of the complexity of the terrain and the relative paucity of meteorological data. Mexico City lies at an elevation of approximately 7500 feet above sea level in a ``U`` shaped basin which opens to the north. The city occupies a major part of the southwest portion of the basin. Upper level winds are provided by rawinsondes at the airport, while low-level winds are measured at several sites within the city. Many of the sites have obstructed upwind fetches for a variety of directions. During the wintertime when the worst air quality episodes occur, the winds are frequently light, and out of the northeast at …

The Waste Isolation Pilot Plant (WIPP) is an experimental facility located in southeastern New Mexico. It has been designed to determine the feasibility of the geologic disposal of defense-generated transuranic waste in a deep bedded-salt formation. The WIPP was also designed for disposal and will operate in that capacity if approved. The WIPP Performance Assessment Department at Sandia National Laboratories has been conducting analyses to assess the long-term performance of the WIPP. These analyses sometimes require the use of expert judgment. This Department has convened several expert-judgment panels and from that experience has developed an internal quality-assurance procedure to guide the formal elicitation of expert judgment. This protocol is based on the principles found in the decision-analysis literature.

A technical, defensible basis for the number and placement of air sampling instruments in a radioactive materials handling facility was developed. Historical air sampling data, process and physicochemical knowledge, qualitative smoke dispersion studies with video documentation, and quantitative trace gas dispersion studies were used to develop a strategy for number and placement of air samplers. These approaches can be used in other facilities to provide a basis for operational decisions. The requirements for retrospective sampling, personal sampling, and real-time monitoring are included. Other relevant operational decisions include selecting the numbers, placement, and appropriate sampling rates for instruments, identifying areas of stagnation or recirculation, and determining the adequacy and efficiency of any sampling transport lines. Justification is presented for using a graded approach to characterizing the workplace and determining air sampling and monitoring needs.

Charge storage devices in which non-equilibrium depletion regions represent stored charge are sensitive to ionizing radiation. This results since the radiation generates electron-hole pairs that neutralize excess ionized dopant charge. Silicon structures, such as dynamic RAM or CCD cells are particularly sensitive to radiation since carrier diffusion lengths in this material are often much longer than the depletion width, allowing collection of significant quantities of charge from quasi-neutral sections of the device. For GaAs the situation is somewhat different in that minority carrier diffusion lengths are shorter than in silicon, and although mobilities are higher, we expect a reduction of radiation sensitivity as suggested by observations of reduced quantum efficiency in GaAs solar cells. Dynamic memory cells in GaAs have potential increased retention times. In this paper, we report the response of a novel GaAs dynamic memory element to transient ionizing radiation. The charge readout technique is nondestructive over a reasonable applied voltage range and is more sensitive to stored charge than a simple capacitor.

Since its beginning, Pittsburgh Energy Technology Center`s (PETC) primary function has been to study and conduct research on coal and its uses and applications. PETC has also been investigating ways in which natural gas can be employed to enhance the use of coal and to convert natural gas into liquid products that can be more readily transported and stored. This review contains five articles which reflect PETC`s mission: State-of-the-Art High Performance Power Systems [HIPPS]; Unconventional Fuel Uses of Natural Gas; Micronized Magnetite -- Beneficiation and Benefits; Reburning for NO{sub x} Reduction; and An Update of PETC`s Process Research Facility.

This paper summarizes the results of a signal taxonomy study of gamma ray burst (GRB) data acquired with sensors on-board the Pioneer-Venus Orbiter (PVO) spacecraft. GRB events produce large fluxes of gamma rays with durations of seconds to minutes and have been observed since the early 1970`s. The true nature of GRBs is still unknown and several competing theories exist. A fundamental point of contention among such theories is whether or not different types of GRB exist. If different types of GRBs are discovered in the existing PVO data base, the differences may correlate with their position or source characteristics. Hence, the goal of this project was to use artificial neural networks to perform signal taxonomy on the GRB data base to determine if unique classes or types of GRBs exist. A total of 26 signal features were identified, some of which can be associated directly with some characteristic of the GRB, such as duration, peak count rate, and gamma ray spectrum hardness. Additional features that were selected included the number of zero crossings in the wavelet transform and the fractal dimension of each signal. A self organizing neural network was used with the signal features to search for correlations …

The results of unit-cell and global diffusion and transport calculations performed for the Georgia Tech heavy water research reactor using the WIMS-D4m code and a new ENDF/B-V based library are presented in this paper. Key cross sections, eigenvalues, neutron fluxes and peak power densities obtained from global diffusion calculations are compared.

The objective of this work was to conduct a feasibility study on a new process, called the plasma quench process, for the conversion of methane to acetylene. FY-1993 efforts were focused on determining the economic viability of this process using bench scale experimental data which was previously generated. This report presents the economic analysis and conclusions of the analysis. Future research directions are briefly described.