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Instrumentation for measuring soft x-rays from laser produced plasmas (open access)

Instrumentation for measuring soft x-rays from laser produced plasmas

Instrumentation has been developed at the Lawrence Livermore Laboratory for measuring subkilovolt x-rays from laser-produced plasmas. This information is needed to do a complete energy balance on laser fusion experiments. The instruments must have thin windows and yet discriminate against the severe environment of other intense target emissions such as ions, electrons, and scattered laser light. Low energy x-ray measurements down to 0.1 keV will be presented using these absolutely calibrated detectors on laser target shots with the LLL Terawatt laser facility, Cyclops. Precautions in using these detectors in a laser fusion target chamber will be enumerated from our experience in using these instruments on hundreds of laser shots.
Date: September 24, 1976
Creator: Slivinsky, V. W.; Ahlstrom, H. G.; Kornblum, H. N.; Koppel, L. N. & Leipelt, G. R.
System: The UNT Digital Library
Switching devices for fusion reactors (open access)

Switching devices for fusion reactors

Switching and power supply problems of neutral atom beam injection systems and superconducting magnets are briefly discussed. Typical power supplies for both systems are described.
Date: March 24, 1976
Creator: Smith, B. H.
System: The UNT Digital Library
Reflectance measurements of vacuum-deposited aluminum films (open access)

Reflectance measurements of vacuum-deposited aluminum films

An integrating sphere technique was used for the measurement of the total and specular reflectance of vacuum-evaporated aluminum films. The appearance of the surface to the naked eye was relatively insensitive to the total reflectance, but was very closely related to the fraction of reflected light that was specularly reflected. Milky or cloudy-appearing aluminum films had a low specular reflectance while mirror-like films had a high specular reflectance. Surface specular reflectance was in turn closely related to film microtopography; roughening features such as hillocks substantially reduced film shininess and hence specular reflectance. Although no extensive study to relate reflectance to deposition parameters was undertaken, specular reflectance was found to be very sensitive to chamber pressure during evaporation. Two alternate techniques for surface appearance measurements were evaluated and correlated with the integrating sphere method; these techniques yielded relative assessments of film shininess that corresponded well with visual appearance and integrating sphere results.
Date: March 24, 1977
Creator: Sherman, D. M.
System: The UNT Digital Library
Identification of Rydberg states in the atomic lanthanides and actinides (open access)

Identification of Rydberg states in the atomic lanthanides and actinides

The study of Rydberg spectra and ionization thresholds of ten lanthanides using several variations of time-resolved resonant multistep techniques is reported. The ionization limits for the lanthanides determined in this way show a systematic dependence on atomic number. A physical model explaining these results is presented. 16 references. (JFP)
Date: May 24, 1977
Creator: Paisner, J. A.; Solarz, R. W.; Worden, E. F. & Conway, J. G.
System: The UNT Digital Library
Optical engineering problems associated with construction of the Shiva Laser Fusion Facility (open access)

Optical engineering problems associated with construction of the Shiva Laser Fusion Facility

The Shiva laser system is part of a new 20 terawatt laser facility at Lawrence Livermore Laboratory. The system contains more than $5,000,000 worth of optics. This paper discusses the various optical components, typical component quantities and specification, and the problem of laser damage to components.
Date: August 24, 1977
Creator: Godwin, R. O.; Bliss, E. S.; Glaze, J. A.; O'Neal, W. C.; Patton, H. G.; Summers, M. A. et al.
System: The UNT Digital Library
Thermal decomposition and reaction of confined explosives. [TNT, TATB, LX-04, LX-10] (open access)

Thermal decomposition and reaction of confined explosives. [TNT, TATB, LX-04, LX-10]

Some new experiments designed to accurately determine the time interval required to produce a reactive event in confined explosives subjected to temperatures which will cause decomposition are described. Geometry and boundary conditions were both well defined so that these experiments on the rapid thermal decomposition of HE are amenable to predictive modelling. Experiments have been carried out on TNT, TATB and on two plastic-bonded HMX-based high explosives, LX-04 and LX-10. When the results of these experiments are plotted as the logarithm of the time to explosion versus 1/T K (Arrhenius plot), the curves produced are remarkably linear. This is in contradiction to the results obtained by an iterative solution of the Laplace equation for a system with a first order rate heat source. Such calculations produce plots which display considerable curvature. The experiments have also shown that the time to explosion is strongly influenced by the void volume in the containment vessel. Results of the experiments with calculations based on the heat flow equations coupled with first-order models of chemical decomposition are compared. The comparisons demonstrate the need for a more realistic reaction model.
Date: May 24, 1976
Creator: Catalano, E.; McGuire, R.; Lee, E.; Wrenn, E.; Ornellas, D. & Walton, J.
System: The UNT Digital Library
Effects of density gradient modification on fluid instability in thermonuclear micro-implosions (open access)

Effects of density gradient modification on fluid instability in thermonuclear micro-implosions

The presence of hydrodynamic fluid instability at the ablation surface puts constraints on the kinds of targets, surface finish, and energy sources that one can use for thermonuclear micro-implosions. If Taylor-like modes grow at near the classical value, one is limited to low aspect ratio shells and surface finishes of 10-100 A. These surface finish requirements can be reduced by 1 to 2 orders of magnitude by exploiting density gradient modification techniques to obtain a shallow density gradient at the ablation surface. For laser driven targets, the gradient is achieved by utilizing suprathermal electrons with a high energy ''get lost'' region to eliminate severe preheat problems. For charged particle sources, the reduction is achieved by introducing an energy spread on the driving source.
Date: September 24, 1976
Creator: Lindl, J. D.; Bangerter, R. O.; Nuckolls, J. H.; Mead, W. C. & Thomson, J. J.
System: The UNT Digital Library
Reduced update Kalman filter: a two-dimensional recursive processor (open access)

Reduced update Kalman filter: a two-dimensional recursive processor

The Kalman filtering method is extended to two-dimensions. The resulting computational load is found to be excessive. The reduced update Kalman filter is derived. It is shown to be optimum in that it minimizes the post update mean square error (mse) under the constraint of updating only the nearby previously processed neighbors. The resulting filter is a stable, nonsymmetric half-plane recursive filter. This method is proposed as a solution of the 2-D filter design problem for stochastic dynamical models.
Date: March 24, 1976
Creator: Woods, J. W. & Radewan, C. H.
System: The UNT Digital Library
Management of radioactive low level liquid, gaseous, and solid wastes in the 200 areas (open access)

Management of radioactive low level liquid, gaseous, and solid wastes in the 200 areas

The practices which are currently used for handling radioactive waste are outlined. These include burial of solid waste, scrubbing of off gas streams, and routing liquid effluents (mostly cooling water) to open ponds where the water percolates to the water table. (LK)
Date: June 24, 1976
Creator: White, A. T.
System: The UNT Digital Library
Surface characterization of ceramic materials. [LEED, AES, XPS, ion scattering spectroscopy, secondary ion mass spectroscopy] (open access)

Surface characterization of ceramic materials. [LEED, AES, XPS, ion scattering spectroscopy, secondary ion mass spectroscopy]

In recent years several techniques have become available to characterize the structure and chemical composition of surfaces of ceramic materials. These techniques utilize electron scattering and scattering of ions from surfaces. Low-energy electron diffraction is used to determine the surface structure, Auger electron spectroscopy and other techniques of electron spectroscopy (ultraviolet and photoelectron spectroscopies) are employed to determine the composition of the surface. In addition the oxidation state of surface atoms may be determined using these techniques. Ion scattering mass spectrometry and secondary ion mass spectrometry are also useful in characterizing surfaces and their reactions. These techniques, their applications and the results of recent studies are discussed. 12 figures, 52 references, 2 tables.
Date: September 24, 1976
Creator: Somorjai, G. A. & Salmeron, M.
System: The UNT Digital Library
Air filtration enhancement using electronic techniques (open access)

Air filtration enhancement using electronic techniques

Dielectrophoretic filtration experiments were conducted on glass, polyester, dacron, Teflon, wool, acrylic and polypropylene filter media. A polydispersed (sigma g = 2.0, ammd = 0.95 ..mu.. m) sodium chloride particle was used as a test aerosol. All materials exhibited significant increases in efficiency with increasing field strengths. Efficiencies of greater than 99 percent could be obtained from glass fiber mats using a 13 kV/cm electric field at 16.3 cm/s face velocity.
Date: June 24, 1976
Creator: Nelson, G. O.; Richards, C. P.; Biermann, A. H.; Taylor, R. D. & Miller, H. H.
System: The UNT Digital Library
MX magnet system. [Electrical and engineering design characteristics] (open access)

MX magnet system. [Electrical and engineering design characteristics]

A conceptual drawing of the MX experiment is given. The central feature of the MX is a large superconducting magnet. The magnet parameters and conductor parameters are listed. The electrical and engineering design of the magnet is given.
Date: June 24, 1976
Creator: Bulmer, R. H.; Calderon, M. O.; Cornish, D. N.; Kozman, T. A. & Sackett, S. J.
System: The UNT Digital Library
Interim program for the management of high-level radioactive liquid waste (open access)

Interim program for the management of high-level radioactive liquid waste

An overview of present operations concerned with the management of Hanford-generated high-level radioactive wastes is presented. Interim storage, leak experience, costs, and program operations are discussed. (LK)
Date: June 24, 1976
Creator: Burton, G. Jr.
System: The UNT Digital Library
Hanford site environment. [Demography, meteorology, geology, hydrology, seismology] (open access)

Hanford site environment. [Demography, meteorology, geology, hydrology, seismology]

A synopsis is given of the detailed characterization of the existing environment at Hanford. The following aspects are covered: demography, land use, meteorology, geology, hydrology, and seismology. It is concluded that Hanford is one of the most extensively characterized nuclear sites. 16 figures. (DLC)
Date: June 24, 1976
Creator: Isaacson, R. E.
System: The UNT Digital Library
Particle and x-ray energy measurements in laser-plasma interaction experiments (open access)

Particle and x-ray energy measurements in laser-plasma interaction experiments

The energy carried by particles and low energy x-rays resulting from irradiation of targets with .5 to 1 TW, 1.06 ..mu..m lasers has been measured. The energy distributions were obtained from measurements at discrete locations using calorimeters and work is in progress to obtain them over a hemisphere with a thermal imaging system. Azimuthal symmetry and polar distributions for different focusing schemes have been determined. The data have been integrated to obtain the absorbed energy and these values compared to box calorimetry and optical energy balance. The relative emission of low energy x-rays from different Z materials can be obtained by comparing these data to charge collector data. Such comparisons also showed that the effective ion charge can be as low as a factor of two below the completely ionized state. The existence of low charge state ions has since been confirmed with high resolutions spectrometers.
Date: September 24, 1976
Creator: Rupert, V. C.; Gunn, S. R.; Holzrichter, J. F.; Glaros, S. S.; Severyn, J. R. & Lee, P.
System: The UNT Digital Library
Hanford long-term high-level waste management program (open access)

Hanford long-term high-level waste management program

An overview of the Hanford Long-Term High-Level Waste Management Program is presented. Four topics are discussed: first, the kinds and quantities of waste that will exist and are included in this program; second, how the plan is structured to solve this problem; third, the alternative waste management methods being considered; and fourth, the technology program that is in progress to carry out this plan. (LK)
Date: June 24, 1976
Creator: Wodrich, D. D.
System: The UNT Digital Library
The Optimizatio of Lead Frame Bond Parameters for Production of Reliable Thermocompression Bonds (open access)

The Optimizatio of Lead Frame Bond Parameters for Production of Reliable Thermocompression Bonds

None
Date: April 24, 1978
Creator: Blazek, R. J., Piper, W. A.
System: The UNT Digital Library
Pyrolysis Model for an alpha Waste Incinerator Prototype. (open access)

Pyrolysis Model for an alpha Waste Incinerator Prototype.

None
Date: May 24, 1978
Creator: Orloff, D. I.
System: The UNT Digital Library
Control of Stress Corrosion Cracking in Storage Tanks Containing Radioactive Waste. (open access)

Control of Stress Corrosion Cracking in Storage Tanks Containing Radioactive Waste.

Stress corrosion of carbon steel storage tanks containing alkaline nitrate radioactive waste, at the Savannah River Plant is controlled by specification of limits on waste composition and temperature. Actual cases of cracking have occurred in the primary steel shell of tanks designed and built before 1960 and were attributed to a combination of high residual stresses from fabrication welding and aggressiveness of fresh wastes from the reactor fuel reprocessing plants. The fresh wastes have the highest concentration of nitrate, which has been shown to be the cracking agent. Also as the waste solutions age and are reduced in volume by evaporation of water, nitrite and hydroxide ions become more concentrated and inhibit stress corrosion. Thus, by providing a heel of aged evaporated waste in tanks that receive fresh waste, concentrations of the inhibitor ions are maintained within specified ranges to protect against nitrate cracking. Tanks designed and built since 1960 have been made of steels with greater resistance to stress corrosion; these tanks have also been heat treated after fabrication to relieve residual stresses from construction operations. Temperature limits are also specified to protect against stress corrosion at elevated temperatures.
Date: April 24, 1978
Creator: Ondrejcin, R. S.; Rideout, S. P. & Donovan, J. A.
System: The UNT Digital Library
Solar energy conference, final report (open access)

Solar energy conference, final report

The conference attendance, publicity and press coverage, brochure mailing, presentations, displays, exhibitors, management seminar checklist, and seminar evaluation by attendees are presented. Also included are the proposal for funding of the conference, the list of attendees, keynote speeches, agenda, and feedback questionnaire. (MHR)
Date: May 24, 1977
Creator: unknown
System: The UNT Digital Library
Primary Factors Governing Hydraulic Fractures in Heterogeneous Stratified Porous Formations (open access)

Primary Factors Governing Hydraulic Fractures in Heterogeneous Stratified Porous Formations

Some primary material, macrostructural and tectonic features of typical geological formations are identified, insofar as they affect the hydraulic fracturing operation whereby suitably treated fluid is pumped into massive crack(s) underground: the retardation or channeling due to strata interfaces, discontinuities and other heterogeneities is roughly characterized, in the context of fully three-dimensional crack shape evolution, and the initiation from oriented boreholes is discussed in detail. A general-purpose numerical scheme is described, efficiently based on a physically transparent distribution of discontinuity multipoles (or dislocations) and the solution of resulting singular integral equations, which permits precise quantification of these effects: in particular, the barriers provided by adjacent stiffer and tougher strata are properly rationalized and the roles of inelastic slippage, blunting, branching, arrest, and re-initiation are placed in more transparent perspective. Stabilization effects due to alterations of pore-fluid pressure (and hence effective decohering stress), or the flux of formation fluid into the open region near to the crack tip, are described as potentially unfavorable for hydrofrac containment. However, the dominant time-dependent mechanism of frac fluid penetration into the narrow crack aperture attracts most attention: this process is very naturally and tractably incorporated in our comprehensive numerical formulation so that realistic simulation of …
Date: August 24, 1978
Creator: Cleary, M. P.
System: The UNT Digital Library
Processing of geothermal brine effluents for injection (open access)

Processing of geothermal brine effluents for injection

The handling and disposal of brine effluents is a critical part of any geothermal conversion process. Brine effluents from the San Diego Gas and Electric/Department of Energy--Geothermal Loop Experimental Facility were characterized for particulate concentration and chemical composition. Bench scale tests were conducted with inorganic and organic coagulants as a means of enhancing the sedimentation process for separation and removal of suspended solids, principally amorphous silica. The effects of temperature, retention time, and pH on the precipitation of supersaturated silica, subsequent floc settling properties, and supernatant clarity were also determined. A design of a pilot scale clarifier now undergoing testing is also described.
Date: March 24, 1978
Creator: Quong, R.; Schoepflin, F. & Stout, N.D.
System: The UNT Digital Library
Relationships between removal processes and residence times for atmospheric pollutants (open access)

Relationships between removal processes and residence times for atmospheric pollutants

This report is concerned with improving estimates for the residence times of atmospheric trace constituents in various atmospheric reservoirs. Residence times are defined only for steady-state conditions; i.e., when the net growth rate vanishes. The most useful case of vanishing net growth rate is when the total growth rate is equal to the decay rate. It is demonstrated that the most important advance towards improving estimates of pollutant residence times is through proper choices of reservoirs. Chosen reservoirs should possess the following features: steady-state conditions, uniform mixing ratio throughout or throughout specified subreservoirs, and subreservoirs chosen in which removal rates can be treated as approximate constants. An example of a poorly mixed reservoir, the stratosphere, is discussed. In another example, it is suggested that commonly used reservoirs for atmospheric CO/sub 2/ have been chosen poorly and that a substantial portion of the anthropogenic CO/sub 2/ released during the past 50 years may still be mixing into the stratosphere. In another example, it is suggested that determination of the dry deposition velocity for accumulation-mode aerosol particles may not be so important as previously thought. To improve estimates for the atmospheric residence times of these particles, it is important to increase knowledge …
Date: March 24, 1978
Creator: Slinn, W.G.N.
System: The UNT Digital Library
Heavy ion clusters in the TDHF approximation. [112 to 384 MeV, cross sections] (open access)

Heavy ion clusters in the TDHF approximation. [112 to 384 MeV, cross sections]

The time-dependent Hartree-Fock method is used to produce time dependent graphical representations of the density contours of the binary cluster in the reactions /sup 14/N(112 MeV) + /sup 12/C, /sup 16/O(384 MeV) + /sup 16/O, and /sup 20/Ne(164 MeV) + /sup 58/Ni. Alpha clustering and multipole shape vibrations are seen. Predictions for d sigma/d..cap omega.., d sigma/dZ/sub f/, and d/sup 2/sigma(E/sub f/)d..cap omega..dE/sub f/vertical/sub z//sub f/ are obtained in the case of /sup 14/N + /sup 12/C and found to agree well with available experimental data. It is concluded that cluster dynamics play an essential role in heavy-ion reactions.
Date: May 24, 1978
Creator: Cusson, R.Y.; Gomez del Campo, J. & Meldner, H.W.
System: The UNT Digital Library