Resource Type

Microwave separation of organic chemicals from mixed hazardous waste (open access)

Microwave separation of organic chemicals from mixed hazardous waste

The feasibility of utilizing the differential heating characteristics of microwave energy (MW) to aid in the chemical extraction and separation process of hazardous organic compounds from mixed hazardous waste, was studied at the INEL. The long-term objective of this work was to identify a practical method of separating or enhancing the separation process of organic hazardous waste components from mixed waste using microwave (MW) frequency radiation. Methods using MW energy for calcination, solidification, and drying of radioactive waste from nuclear facilities is becoming more attractive. In order to study the effectiveness of MW heating, samples of several organic chemicals simulating those which may be found at the Radioactive Waste Management Complex at the INEL were exposed to MW energy. Vapor collection and analysis was performed as a function of time, signal frequency, and MW power throughout the process. Signal frequencies ranging from 900 MHz t 8000 MHz were used. Although the signal frequency bandwidth of the selectivity was quite broad, for the material tested an indication of the frequency dependence in the selectivity of MW heating was given. Greater efficiency in terms of energy used and time required was observed. The relatively large electromagnetic field intensities generated at the resonant …
Date: January 1, 1992
Creator: Anderson, A. A. & Albano, R. K.
System: The UNT Digital Library
Geothermal waste treatment biotechnology: Progress and advantages to the utilities (open access)

Geothermal waste treatment biotechnology: Progress and advantages to the utilities

Development of biotechnology for treatment of geothermal residual waste is aimed at the application of low-cost biochemical processes for the surface treatment and disposal of residual geothermal sludges. These processes, in addition to the lowering of disposal cost, are designed to be environmentally acceptable. Recent studies at Brookhaven National Laboratory (BNL) have shown that optimization of several process variables results in fast rates (<24h) of metal removal from residual sludges at acidic pH ({minus}1--2). Optimization of the process variables also enables the removal of radioactive isotopes. In addition, the aqueous phase produced during the bioprocessing which contains solubilized metals can be further treated in a manner which precipitates out the metals and renders the aqueous effluent toxic metal free. In this paper, the various process options will be discussed in terms of biotreatment variables. Chemical composition before and after biotreatment will also be discussed in terms of long-range effects, quality assurance and potential disposal costs.
Date: March 1, 1992
Creator: Premuzic, E.T.; Lin, M.S. & Jin, J.
System: The UNT Digital Library
Fractional processes and nuclear disassembly in very-heavy-ion collisions in the Fermi energy regime (open access)

Fractional processes and nuclear disassembly in very-heavy-ion collisions in the Fermi energy regime

Exclusive measurements of charged products and neutrons were performed for the reactions {sup 197}Au + (29 MeV/u) {sup 208}Pb and {sup 209}Bi + (28.2 MeV/u) {sup 136}Xe. The multiplicities of neutrons and charged particles are found to indicate collision impact parameters with different sensitivities. Characteristic correlations observed between massive products and light particles suggest the dominance of the damped-reaction mechanism in the Fermi energy domain. For central collisions, massive fragments are no longer observed, and a considerable fraction of the mass of the system is found disassembled into light particles and clusters. 75 refs., 19 figs.
Date: January 1, 1991
Creator: Schroeder, W.U.
System: The UNT Digital Library
Vibration considerations in the design of the Advanced Photon Source at Argonne National Laboratory (open access)

Vibration considerations in the design of the Advanced Photon Source at Argonne National Laboratory

The Advanced Photon Source (APS), a new synchrotron radiation facility being built at Argonne National Laboratory, will provide the world's most brilliant X-ray beams for research in a wide range of technical fields. Successful operation of the APS requires an extremely stable positron closed orbit. Vibration of the storage ring quadrupole magnets, even in the submicron range, can lead to distortion of the positron closed orbit and to potentially unacceptable beam emittance growth, which results in degraded performance. This paper presents an overview of the technical approach used to minimize vibration response, beginning at the conceptual stage, through design and construction, and on to successful operation. Acceptance criteria relating to maximum allowable quadrupole magnet vibration are discussed. Soil properties are used to determine resonant frequencies of foundations and to predict attenuation characteristics. Two sources are considered to have the potential to excite the foundation: far-field sources, which are produced external to the facility, and near-field sources, which are produced within the facility. Measurements of ambient ground motion, monitored to determine far- field excitation, are presented. Ambient vibration was measured at several operating facilities within Argonne to gain insight on typical near-field excitation sources. Discussion covers the dynamic response characteristics of …
Date: January 1, 1991
Creator: Jendrzejczyk, J.A. & Wambsganss, M.W.
System: The UNT Digital Library
Thermodynamics of natural and industrial waters (open access)

Thermodynamics of natural and industrial waters

The most effective general formulations of thermodynamic equations for multicomponent aqueous solutions are discussed with respect to various ranges of temperature, pressure and composition with emphasis on solutes important in natural or industrial waters. A familiar equation in molality and in excess Gibbs energy is very successful up to 300{degree}C and ionic strength 6 mol{center dot}kg{sup {minus}1}, and can often be extended to 350{degree}C or above at high pressure and in favorable cases to ionic strength 12 or even 20. Alternate methods valid to higher solute compositions, even to pure fused salts, are described. A more difficult situation arises near the critical point of water where the compressibility becomes infinite and a Helmholtz energy basis must be adopted. Existing equations for this range and still higher temperatures and pressures are considered and possible improvements discussed. 85 refs., 13 figs., 3 tabs.
Date: August 1, 1991
Creator: Pitzer, K.S.
System: The UNT Digital Library
Aging Aircraft NDI Development and Demonstration Center (AANC): An overview (open access)

Aging Aircraft NDI Development and Demonstration Center (AANC): An overview

A major center with emphasis on validation of nondestructive inspection techniques for aging aircraft, the Aging Aircraft NDI Development and Demonstration Center (AANC), has been funded by the FAA at Sandia National Laboratories. The Center has been assigned specific tasks in developing techniques for the nondestructive inspection of static engine parts, assessing inspection reliability (POD experiments), developing test beds for nondestructive inspection validation, maintaining a FAA library of characterized aircraft structural test specimens, and leasing a hangar to house a high flight cycle transport aircraft for use as a full scale test bed. 3 refs.
Date: January 1, 1991
Creator: Walter, P. L.
System: The UNT Digital Library
The neutrinos in muon decay (open access)

The neutrinos in muon decay

We review the available information on the identity of the neutrino states emitted in muon decay, and discuss the exotic decay {mu}{sup +} {yields} e{sup +} {bar {nu}}{sub e}{nu}{sub {mu}}. 22 refs.
Date: October 21, 1991
Creator: Herczeg, P.
System: The UNT Digital Library
Predicting aquatic macrophyte modeling of a new freshwater lake using remote sensing (open access)

Predicting aquatic macrophyte modeling of a new freshwater lake using remote sensing

Par Pond and L Lake are reservoirs on the Savannah River Site in South Carolina. Beds of aquatic macrophytes (primarily cattail and waterlilies) exist in Par Pond and are now beginning to develop in L Lake. Biophysical knowledge about Par Pond was used to develop environmental constraint criteria' to predict the future spatial distribution of aquatic macrophytes in L Lake. The L Lake biophysical data were placed in a 5 {times} 5 m raster geographic information system (GIS) and analyzed using Boolean logic. Areas in L Lake which were {le}4 m in depth, {le}10% slope, had a fetch of {le}500 m, and on suitable soil were identified. The final GIS model predicted the spatial distribution of 37.30 ha of aquatic macrophytes which met the environmental constraint criteria (cattails = 12.29 ha and waterlilies = 25.01 ha).
Date: January 1, 1992
Creator: Jensen, J. R.; Narumalani, S.; Weatherbee, O.; Morris, K. S., Jr. & Mackey, H. E., Jr.
System: The UNT Digital Library
Dependence of secondary ion emission from organic material on the energy loss of the impacting heavy ion (open access)

Dependence of secondary ion emission from organic material on the energy loss of the impacting heavy ion

Samples of the amino acid valine were irradiated by 2.5 MeV-Ar, 0.8 MeV-Kr and 1.0 MeV Xe beams from the Argonne Dynamitron accelerator in order to study the energy distributions of ejected secondary ions. For Kr and Xe the nuclear stopping power exceeded the electronic stopping power by a factor 2 or 3, respectively, but the functional shape of the energy distributions and the mean ejection energies (0.9--1.4 eV) indicated that the molecular ions (M{plus minus}H){sup {plus minus}} are desorbed by an electronic sputter process. Contributions of atomic collision cascades were observed for the H{sup {minus}} ion. In the second part of the article, the overall dependence of molecular ion yields on the electronic energy loss is discussed in the framework of recent desorption models and the structure of the nuclear track.
Date: January 1, 1991
Creator: Hunt, J.E. (Argonne National Lab., IL (United States)) & Wien, K. (Technische Hochschule Darmstadt (Germany). Inst. fuer Kernphysik)
System: The UNT Digital Library
Molecular Sieve Regeneration System for assaying HTO from detritiation systems (open access)

Molecular Sieve Regeneration System for assaying HTO from detritiation systems

A Molecular Sieve Regeneration System (MSRS) is being added to the existing Tritium Waste Treatment system (TWT) within the Tritium Systems Test Assembly (TSTA) at the Los Alamos National Laboratory. This system is an upgrade to the TWT to provide accurate measurements of the liquid waste generated from this system. Within the TWT, hydrogen isotopes are removed from the effluent gas stream by the catalytic conversion to water and the subsequent removal of water by molecular sieve trapping prior to the release to the environment. Within the TWT and similar systems, molecular sieve regeneration is required to rejuvenate the beds. The major difference of the MSRS and other regeneration systems is the capability of direct assay of long-term storage waste containers. This is accomplished with loop-flow regeneration, water collection, and tritiated water assay by scintillation and calorimetric techniques. This paper describes the MSRS in detail and how it is interfaced with the Tritium Waste Treatment system.
Date: January 1, 1992
Creator: Nasise, J.E.; Anderson, J.L. (Los Alamos National Lab., NM (United States)) & Naruse, Y. (Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan))
System: The UNT Digital Library
Magnetic fusion with high energy self-colliding ion beams (open access)

Magnetic fusion with high energy self-colliding ion beams

Field-reversed configurations of energetic large orbit ions with neutralizing electrons have been proposed as the basis of a fusion reactor. Vlasov equilibria consisting of a ring or an annulus have been investigated. A stability analysis has been carried out for a long thin layer of energetic ions in a low density background plasma. There is a growing body of experimental evidence from tokamaks that energetic ions slow down and diffuse in accordance with classical theory in the presence of large non-thermal fluctuations and anomalous transport of low energy (10 keV) ions. Provided that major instabilities are under control, it seems likely that the design of a reactor featuring energetic self-colliding ion beams can be based on classical theory. In this case a confinement system that is much better than a tokamak is possible. Several methods are described for creating field reversed configurations with intense neutralized ion beams.
Date: June 1, 1992
Creator: Rostoker, N.; Wessel, F. (California Univ., Irvine, CA (United States)); Maglich, B. (Advanced Physics Corp., Irvine, CA (United States)) & Fisher, A. (Naval Research Lab., Washington, DC (United States))
System: The UNT Digital Library
A comparison of spanwise aerodynamic loads estimated from measured bending moments versus direct pressure measurements on horizontal axis wind turbine blades (open access)

A comparison of spanwise aerodynamic loads estimated from measured bending moments versus direct pressure measurements on horizontal axis wind turbine blades

Two methods can be used to determine aerodynamic loads on a rotating wind turbine blade. The first is to make direct pressure measurements on the blade surface. This is a difficult process requiring costly pressure instrumentation. The second method uses measured flap bending moments in conjunction with analytical techniques to estimate airloads. This method, called ALEST, was originally developed for use on helicopter rotors and was modified for use on horizontal axis wind turbine blades. Estimating airloads using flap bending moments in much simpler and less costly because measurements can be made with conventional strain gages and equipment. This paper presents results of airload estimates obtained using both methods under a variety of operating conditions. Insights on the limitations and usefulness of the ALEST bending moment technique are also included. 10 refs., 6 figs.
Date: October 1, 1991
Creator: Simms, D A & Butterfield, C P
System: The UNT Digital Library
Mechanism of (n,. gamma. ) reaction at low neutron energies (open access)

Mechanism of (n,. gamma. ) reaction at low neutron energies

We discuss the interplay between direct capture, valence capture, and compound-nuclear capture in attempting to explain the vast amount of capture data for light-mass nuclei. 13 refs.
Date: January 1, 1991
Creator: Raman, S. (Oak Ridge National Lab., TN (United States)) & Lynn, J.E. (Los Alamos National Lab., NM (United States))
System: The UNT Digital Library
Evaluation of proposed designs for streamflow monitoring structures at waste disposal sites (open access)

Evaluation of proposed designs for streamflow monitoring structures at waste disposal sites

Design of small surface water monitoring stations associated with waste sites requires an approach that balances several problems. The monitoring site must have a capacity for a wide range of flows, allow accurate measurements over the full performance range, minimize effects from accumulation of contaminated sediments, and minimize costs of construction and operation. Selecting a station design that takes these factors into consideration can be done systematically through use of formal decision analysis. The paper discusses the effectiveness of various hydraulic structures as flumes and weirs to monitor stream flow and drainage. The process has produced the most viable alternative designs and yielded fully documented guidelines for designing new stations as they are needed. 7 refs., 6 figs., 3 tabs.
Date: January 1, 1991
Creator: Clapp, R. B.; Borders, D. M.; Tardiff, M. F. & Huff, D. D.
System: The UNT Digital Library
Operating experience with the ALS linac (open access)

Operating experience with the ALS linac

The linac injector for the Advanced Light Source (ALS) at LBL was recently put into operation. Energy is 50 MeV, frequency 3 GHz. The electron gun delivers up to 6nC in a 3.0-ns bunch at 120 kV. A train of bunches is injected into a 1-Hz booster and accelerated to 1.5 GHz for storage ring injection. A magnetic analysis system is used for optimizing the linac. Measured beam properties from the gun and after acceleration in the linac are described. 9 refs., 3 figs.
Date: May 1, 1991
Creator: Selph, F. & Massoletti, D.
System: The UNT Digital Library
Condensation in a two-phase pool (open access)

Condensation in a two-phase pool

We consider the case of vapor condensation in a liquid pool, when the heat transfer is controlled by heat losses through the walls. The analysis is based on drift flux theory for phase separation in the pool, and determines the two-phase mixture height for the pool. To our knowledge this is the first analytical treatment of this classic problem that gives an explicit result, previous work having established the result for the evaporative case. From conservation of mass and energy in a one-dimensional steady flow, together with a void relation between the liquid and vapor fluxes, we determine the increase in the mixture level from the base level of the pool. It can be seen that the thermal and hydrodynamic influences are separable. Thus, the thermal influence of the wall heat transfer appears through its effect on the condensing length L*, so that at high condensation rates the pool is all liquid, and at low rates overflows (the level swell or foaming effect). Similarly, the phase separation effect hydrodynamically determines the height via the relative velocity of the mixture to the entering flux. We examine some practical applications of this result to level swell in condensing flows, and also examine …
Date: January 1, 1991
Creator: Duffey, R.B. (Brookhaven National Lab., Upton, NY (United States)) & Hughes, E.D. (EG and G Idaho, Inc., Idaho Falls, ID (United States))
System: The UNT Digital Library
A study of tau decays of the W boson at CDF (Collider Detector at Fermilab) (open access)

A study of tau decays of the W boson at CDF (Collider Detector at Fermilab)

A report is given of a search for tau decays of the W boson in p{bar p} collisions at {radical}s = 1.8 TeV using the Collider Detector at Fermilab (CDF). A description of a hardware trigger specifically designed to enhance the number of events with tau decays is presented along with the results of a preliminary analysis of data taken during the 1988--89 run of CDF. 10 refs., 4 figs.
Date: January 3, 1990
Creator: Gladney, L. D.
System: The UNT Digital Library
Repetitive, small-bore two-stage light gas gun (open access)

Repetitive, small-bore two-stage light gas gun

A repetitive two-stage light gas gun for high-speed pellet injection has been developed at Oak Ridge National Laboratory. In general, applications of the two-stage light gas gun have been limited to only single shots, with a finite time (at least minutes) needed for recovery and preparation for the next shot. The new device overcomes problems associated with repetitive operation, including rapidly evacuating the propellant gases, reloading the gun breech with a new projectile, returning the piston to its initial position, and refilling the first- and second-stage gas volumes to the appropriate pressure levels. In addition, some components are subjected to and must survive severe operating conditions, which include rapid cycling to high pressures and temperatures (up to thousands of bars and thousands of kelvins) and significant mechanical shocks. Small plastic projectiles (4-mm nominal size) and helium gas have been used in the prototype device, which was equipped with a 1-m-long pump tube and a 1-m-long gun barrel, to demonstrate repetitive operation (up to 1 Hz) at relatively high pellet velocities (up to 3000 m/s). The equipment is described, and experimental results are presented. 124 refs., 6 figs., 5 tabs.
Date: January 1, 1991
Creator: Combs, S. K.; Foust, C. R.; Fehling, D. T.; Gouge, M. J. & Milora, S. L.
System: The UNT Digital Library
Growth, preparation, and dielectric properties of monodomain single crystal PbTiO sub 3 (open access)

Growth, preparation, and dielectric properties of monodomain single crystal PbTiO sub 3

A method is described for obtaining monodomain PbTiO{sub 3} single crystals with high electrical resistivity (10{sup 10}{Omega} cm) and low dielectric frequency dispersion. The single crystals of PbTiO{sub 3} were grown by flux solution method. Space charge related defects, which result in the large dielectric frequency dispersion, were eliminated by heat treatments. 90{degrees} domains were removed by applying a unidirectional compressive stress along the <100> crystallographic direction. The monodomain single crystals of PbTiO{sub 3} were identified by cross polarized light optical microscopy and by X-ray diffraction (rocking curve). The anisotropic dielectric constants of these high quality single crystals were measured as a function of temperature. The results differ from the data reported previously in the literature.
Date: May 1, 1992
Creator: Li, Z.; Xu, X. Z.; Dai, X. H.; Lam, D. J. & Chan, S. K.
System: The UNT Digital Library
Ceramic microstructures and their elucidation by imaging, diffraction and spectroscopic methods (open access)

Ceramic microstructures and their elucidation by imaging, diffraction and spectroscopic methods

The development and potential utilization of ceramic materials is dependent on a systematic effort involving processing, characterization and appropriate property measurements. The methods of characterization are numerous and it is important to employ the one that is appropriate to the problem both in terms of its information content and the achievable level of resolution. With the incorporation of fine probe forming capabilities in a transmission electron microscope and the development of related diffraction, imaging and spectroscopic methods, it is now possible to obtain structural and chemical information from the same region of the sample at high spatial resolution. In this review, recent advances along with representative examples in the application of high resolution electron microscopy (HREM), convergent beam electron diffraction (CBED), low atomic number element microanalysis by x-ray emission spectroscopy (XES), fine structures in electron energy-loss spectroscopy (EELS) and specific site occupancy determination by channeling experiments are discussed.
Date: February 1, 1992
Creator: Kirshnan, K.M.
System: The UNT Digital Library
The use of synchrotron radiation for the analysis of coal combustion products (open access)

The use of synchrotron radiation for the analysis of coal combustion products

An understanding of the chemical composition of such slags under boiler operating conditions and as function of the mineral composition of various coals is the ultimate goal of this program. The experiment involves scanning through the K- or L-shell absorption edge of the element in question. The structure of the absorption edge, consisting of transitions to unoccupied molecular levels, can be compared to those of model compounds for identification. The relative position of the absorption edge can yield information regarding the oxidation state of the element. This portion is the X-ray Absorption Near Edge Structure (XANES) portion of the spectrum. The Extended X-ray Absorption Fine Structure (EXFAS) region, extending from about 60 eV above the absorption edge, represents scattering from neighboring constituents and can be used to determine the coordination number of coordination distance of a specific element from its neighboring atoms. The best source of excitation energy for these experiments is an electron storage ring emitting synchrotron radiation (SR). The National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory is a 2.5 GeV storage ring and emits a continuous spectrum of x rays to an energy of about 30 keV. Beam line X-19A is dedicated to XANES and EXAFS …
Date: May 1, 1992
Creator: Manowitz, B. & Gordon, B.
System: The UNT Digital Library
Ab initio calculations on collisions of low energy electrons with polyatomic molecules (open access)

Ab initio calculations on collisions of low energy electrons with polyatomic molecules

The Kohn variational method is one of simplest, and oldest, techniques for performing scattering calculations. Nevertheless, a number of formal problems, as well as practical difficulties associated with the computation of certain required matrix elements, delayed its application to electron--molecule scattering problems for many years. This paper will describe the recent theoretical and computational developments that have made the complex'' Kohn variational method a practical tool for carrying out calculations of low energy electron--molecule scattering. Recent calculations on a number of target molecules will also be summarized. 41 refs., 7 figs.
Date: August 1, 1991
Creator: Rescigno, T. N.
System: The UNT Digital Library
Variability of surface fluxes over a heterogeneous semi-arid grassland (open access)

Variability of surface fluxes over a heterogeneous semi-arid grassland

Efforts are increasing throughout the research community to improve the predictive capabilities of general circulation models (GCMs). The US Department of Energy's Atmospheric Radiation Measurement (ARM) program has stated its goals as improving the representation and parameterization of cloud radiative forcing and feedbacks in GCMs by a combined modeling and experimental approach. Along with ambient atmospheric conditions, including advection of water vapor and cloud nuclei from other regions, cloud dynamics depend on surface fluxes of heat and water vapor. The lower boundary of the GCM modeling domain, the earth's surface, exerts a strong influence on regional dynamics of heat and water vapor, and the heterogeneity in the surface features can be responsible for generating regional mesoscale circulation patterns. Changes in the surface vegetation due to anthropogenic activity can cause substantial changes in the ratio of sensible to latent heat flux and result in climate changes that may be irreversible. A broad variety of models for representing energy fluxes are in use, from individual leaf and canopy models to mesoscale atmospheric models and GCMs. Scaling-up a model is likely to result in significant errors, since biophysical responses often have nonlinear dependence on the abiotic environment. Thus, accurate and defensible methods for …
Date: January 1, 1991
Creator: Barnes, F.J.; Porch, W.; Cooper, D. (Los Alamos National Lab., NM (United States)); Kunkel, K.E. (Illinois Univ., Urbana, IL (United States)); Hipps, L. & Swiatek, E. (Utah State Univ., Logan, UT (United States))
System: The UNT Digital Library
Evaluation of a Cray performance tool using a large hydrodynamics code (open access)

Evaluation of a Cray performance tool using a large hydrodynamics code

This paper will discuss one of these automatic tools that has been developed recently by Cray Research, Inc. for use on its parallel supercomputer. The tool is called ATEXPERT; when used in conjunction with the Cray Fortran compiling system, CF77, it produces a parallelized version of a code based on loop-level parallelism, plus information to enable the programmer to optimize the parallelized code and improve performance. The information obtained through the use of the tool is presented in an easy-to-read graphical format, making the digestion of such a large quantity of data relatively easy and thus, improving programmer productivity. In this paper we address the issues that we found when the took a large Los Alamos hydrodynamics code, PUEBLO, that was highly vectorizable, but not parallelized, and using ATEXPERT proceeded to parallelize it. We show that through the advice of ATEXPERT, bottlenecks in the code can be found, leading to improved performance. We also show the dependence of performance on problem size, and finally, we contrast the speedup predicted by ATEXPERT with that measured on a dedicated eight-processor Y-MP.
Date: January 1, 1992
Creator: Lord, K.M. (Cray Research, Inc., Eagan, MN (United States)) & Simmons, M.L. (Los Alamos National Lab., NM (United States))
System: The UNT Digital Library