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Plasma confinement in the TMX tandem mirror (open access)

Plasma confinement in the TMX tandem mirror

Plasma confinement in the Tandem Mirror Experiment (TMX) is described. Axially confining potentials are shown to exist throughout the central 20-cm core of TMX. Axial electron-confinement time is up to 100 times that of single-cell mirror machines. Radial transport of ions is smaller than axial transport near the axis. It has two parts at large radii: nonambipolar, in rough agreement with predictions from resonant-neoclassical transport theory, and ambipolar, observed near the plasma edge under certain conditions, accompanied by a low-frequency, m = 1 instability or strong turbulence.
Date: April 29, 1981
Creator: Hooper, E. B. Jr.; Allen, S. L. & Casper, T. A.
System: The UNT Digital Library
Performance of the AFS vertex detector at the CERN ISR (open access)

Performance of the AFS vertex detector at the CERN ISR

The central detector of the Axial Field Spectrometer (AFS) is a cylindrical drift chamber using a bicycle-wheel geometry. Its design has been optimized for jet-like events with high track densities. This is accomplished through a high degree of azimuthal segmentation (4/sup 0/ sectors) with up to 42 space points per track, using measurements of drift time and charge division. Particle identification in the non-relativistic region is obtained by (dE/dx) sampling. The detector is operated in an inhomogeneous magnetic field at event rates of typically 5 x 10/sup 5/ collisions per second. Preliminary results will be presented on the detector performance achieved after one year of operation at the ISR.
Date: April 28, 1981
Creator: Botner, O.; Burkert, V. & Cockerill, D.
System: The UNT Digital Library
Sodium Depletion on Glass Surfaces During Auger Analysis (open access)

Sodium Depletion on Glass Surfaces During Auger Analysis

The kinetics of the depletion of sodium on glass surfaces during Auger Electron Spectroscopic analysis is investigated. The decay process is mathematically represented as a sum of two single decaying exponential functions. This behavior may be described by a mechanism that accounts for the neutralization of sodium ions by the electron beam. Sodium ions and neutral sodium atoms are depleted by several known processes.
Date: April 22, 1981
Creator: Whitkop, P.G.
System: The UNT Digital Library
One-dimensional magnetohydrodynamic calculations of a hydrogen-gas puff (open access)

One-dimensional magnetohydrodynamic calculations of a hydrogen-gas puff

A one-dimensional Lagrangian calculation of the implosion of a hydrogen gas puff is presented. At maximum compression, 60% of the mass is located in a density spike .5 mm off the axis with a half width of 40 ..mu..m. The temperature on axis reaches 200 eV.
Date: April 20, 1981
Creator: Maxon, S. & Nielsen, P.D.
System: The UNT Digital Library
Streak-camera recording of simultaneous optical and x-ray signals (open access)

Streak-camera recording of simultaneous optical and x-ray signals

An S-1 optical streak camera with 10-ps (optical) temporal resolution simultaneously records reflected 1.06-..mu..m laser light and suprathermal (> 30 keV) x rays from laser fusion targets. To make these measurements, the camera x-ray sensitivity is increased 30-fold without significant loss of temporal resolution by increasing the effective slit width from the normal 50 ..mu..m to 1500 ..mu..m. The measurement system is described and sample data are presented.
Date: April 20, 1981
Creator: Lerche, R. A.; Medecki, H.; Phillips, G. E. & Thomas, S. W.
System: The UNT Digital Library
Metallic and nonmetallic coatings for ICF targets (open access)

Metallic and nonmetallic coatings for ICF targets

Some fusion targets designed to be driven by 0.35 to 1 ..mu..m laser light are glass spheres coated with layers of various materials such as hydrocarbons, fluorocarbons, beryllium, copper, gold, platinum, etc. The glass shell, which is filled with gas, liquid or solid deuterium-tritium fuel, must have remarkably good surface and wall thickness uniformity. Methods for depositing the various materials will be discussed. They include plasma polymerization, electro-deposition, sputtering and evaporation. Many of the difficulties encountered in the coating processes are the result of coating on free spheres with very small radii - 35 to 500 micrometers. Several means of overcoming the problems will be described and experimental results presented.
Date: April 17, 1981
Creator: Hendricks, C. D.; Crane, J. K.; Hsieh, E. J. & Meyer, S. F.
System: The UNT Digital Library
Transposable elements and genetic instabilities in crop plants (open access)

Transposable elements and genetic instabilities in crop plants

Transposable elements have long been associated with certain unstable loci in maize and have been intensively studied by McClintock and others. It is known that a transposable element can control the expression of the structural genes at the locus where it resides. These controlling elements in maize are now beginning to be studied at the molecular level. Using recombinant molecular probes we have been able to describe the changes induced by the controlling element Ds at the shrunken locus. Ds elements appear to be large and dissimilar insertions into the wild-type locus - two elements actually map within the transcribed region of the gene. Genetic instabilities have been described in other economically important plants but the bases for these phenomena have not been understood. We believe that it is likely that some of these instabilities are the result of transposable element activity much as in the case of maize.
Date: April 10, 1981
Creator: Burr, B. & Burr, F.
System: The UNT Digital Library
Electromagnetic velocity gauge: use of multiple gauges, time response, and flow perturbations (open access)

Electromagnetic velocity gauge: use of multiple gauges, time response, and flow perturbations

We have developed an in-situ electromagnetic velocity (EMV) gauge system for use in multiple-gauge studies of initiating and detonating explosives. We have also investigated the risetime of the gauge and the manner in which it perturbs a reactive flow. We report on the special precautions that are necessary in multiple gauge experiments to reduce lead spreading, simplify target fabrication problems and minimize cross talk through the conducting explosive. Agreement between measured stress records and calculations from multiple velocity gauge data give us confidence that our velocity gauges are recording properly. We have used laser velocity interferometry to measure the gauge risetime in polymethyl methacrylate (PMMA). To resolve the difference in the two methods, we have examined hydrodynamic and material rate effects. In addition, we considered the effects of shock tilt, electronic response and magntic diffusion on the gauge's response time.
Date: April 8, 1981
Creator: Erickson, L. M.; Johnson, C. B.; Parker, N. L.; Vantine, H. C.; Weingart, R. C. & Lee, R. S.
System: The UNT Digital Library
Heavy-ion inertial fusion: comments on achievable temperatures for disk-heating experiments using proposed accelerator (open access)

Heavy-ion inertial fusion: comments on achievable temperatures for disk-heating experiments using proposed accelerator

Calculations suggest that experiments relating to beam deposition, focusing and transport can be performed within the context of current test-bed accelerator design proposals. Since the test beds have lower ion kinetic energy and beam pulse power as compared to reactor drivers, we achieve high-beam intensities at the focal spot by using short focal distance and properly designed beam optics. In this regard, the extremely low beam emittance of suggested multi-beam designs are very useful. Preliminary results suggest that intensities of greater than 100 TW/cm/sup 2/ are achievable. Given these intensities, deposition experiments with heating of disks to greater than 100 eV are expected. We could also expect as much as 1 to 3 kA of incident ion current on these disks with beam intensities almost comparable to that of reactor targets. Thus, if any anomalous plasma effects on deposition emerge, the conditions should be available for testing some of them. On the other hand, these deposition experiments have low ion kinetic energy per nucleon. About 4 to 5 MeV/nucleon is achievable if lighter ions such as sodium were used. But for lighter ions, plasma effects in deposition might be more severe because heavy-ion beams are more stiff.
Date: April 7, 1981
Creator: Mark, J. W. K.; Bangerter, R. O.; Fawley, W. M.; Yu, S.; Garren, A. & Krafft, G.
System: The UNT Digital Library
Agriculture, greenhouse, wetland and other beneficial uses of geothermal fluids and heat (open access)

Agriculture, greenhouse, wetland and other beneficial uses of geothermal fluids and heat

The status for related beneficial uses including agriculture, greenhousing, and geothermal wetlands is presented. Data published for the geothermal fluids found in areas of China have been examined and compared with the geothermal fluids used in the agriculture evaluations in the United States. This comparison indicates that the geothermal fluids found in parts of China are similar to those used in the US agriculture experiments. Greenhousing is addressed largely from the standpoint of hardware systems and technology being employed or being proposed in the United States.
Date: April 5, 1981
Creator: Schmitt, R. C.
System: The UNT Digital Library
Active Space Heating and Hot Water Supply With Solar Energy (open access)

Active Space Heating and Hot Water Supply With Solar Energy

Technical and economic assessments are given of solar water heaters, both circulating, and of air-based and liquid-based solar space heating systems. Both new and retrofit systems are considered. The technical status of flat-plate and evacuated tube collectors and of thermal storage is also covered. Non-technical factors are also briefly discussed, including the participants in the use of solar heat, incentives and deterrents. Policy implications are considered as regards acceleration of solar use, goals for solar use, means for achieving goals, and interaction of governments, suppliers, and users. Government actions are recommended. (LEW)
Date: April 1, 1981
Creator: Karaki, S. & Loef, G. O. G.
System: The UNT Digital Library
Angular Momentum Transfer and Partition in the Deep-Inelastic Reaction: 664 MeV {sup 84}Kr + {sup nat}Ag. (open access)

Angular Momentum Transfer and Partition in the Deep-Inelastic Reaction: 664 MeV {sup 84}Kr + {sup nat}Ag.

In- and out-of plane angular distributions have been measured for sequential alpha decay from target-like fragments produced in fully relaxed heavy-ion collisions. At angles equal to or larger than the target-recoil direction, the {alpha}-particle energy spectra are evaporation- like and the in-plane angular distributions are consistent with isotropy in the rest frame of the target recoil. The out-of-plane distributions exhibit an anisotropy of approximately two. Fragment spins were extracted from these distributions as a function of mass asymmetry. These spins are in agreement with those obtained from a simultaneous gamma-ray multiplicity measurement. Both the fragment kinetic energies and intrinsic spins are consistent with rigid rotation of an intermediate complex consisting of two substantially deformed spheroids in near proximity.
Date: April 1981
Creator: Sobotka, L. G.; Hsu, C. C.; Wozniak, G. J.; Morrissey, D. J. & Moretto, L. G.
System: The UNT Digital Library
Bilogical effects of ionizing radiation: epidemiological surveys and laboratory animal experiments. Implications for risk evaluation and decision processes (open access)

Bilogical effects of ionizing radiation: epidemiological surveys and laboratory animal experiments. Implications for risk evaluation and decision processes

General background is given for an understanding of the potential health effects in populations exposed to low-level ionizing radiations. The discussion is within the framework of the scientific deliberations and controversies that arose during preparation of the current report of the committee on the biological effects of ionizing radiation of the National Academy of Science - National Research Council (1980 Beir-III Report). (ACR)
Date: April 1, 1981
Creator: Fabrikant, Jacob I.
System: The UNT Digital Library
Bound water in Kevlar 49 fibers (open access)

Bound water in Kevlar 49 fibers

From elemental analyses, thermogravimetric-mass spectroscopy studies and re-evaluation of previous water diffusion studies in Kevlar 49 fibers it is concluded that these fibers can contain two types of sorbed moisture. The fibers can absorb up to approx. 6 wt % loosely bound water with an activation energy for outgassing by desorption of 6 kcal/mole. This loosely bound water is a direct result of the presence of Na/sub 2/SO/sub 4/ impurities and the perturbations they induce on the packing of the rod-like poly (p-phenylene terephthalamide) macromolecules. Kevlar 49 fibers also inherently contain up to 30 wt % additional water which is tightly bound within the crystal lattice. This water exhibits an activation energy for outgassing by diffusion of approx. 40 kcal/mole and is only evolved from the fiber in significant quantities at t > 350/sup 0/C over a period of hours.
Date: April 1, 1981
Creator: Garza, R. G.; Pruneda, C. O. & Morgan, R. J.
System: The UNT Digital Library
Calculation of doses received while crossing a plume of radioactive material (open access)

Calculation of doses received while crossing a plume of radioactive material

A method has been developed for determining the dose received by a person while crossing a plume of radioactive material. The method uses a Gaussian plume model to arrive at a dose rate on the plume centerline at the position of the plume crossing. This dose rate may be due to any external or internal dose pathway. An algebraic formula can then be used to convert the plume centerline dose rate to a total dose integrated over the total time of plume crossing. Correction factors are presented for dose pathways in which the dose rate is not normally distributed about the plume centerline. The method is illustrated by a study done at the Pacific Northwest Laboratory, and results of this study are presented.
Date: April 1, 1981
Creator: Scherpelz, R.I. & Desrosiers, A.E.
System: The UNT Digital Library
CAMAPPLE: CAMAC interface to the Apple computer (open access)

CAMAPPLE: CAMAC interface to the Apple computer

The advent of the personal microcomputer provides a new tool for the debugging, calibration and monitoring of small scale physics apparatus, e.g., a single detector being developed for a larger physics apparatus. With an appropriate interface these microcomputer systems provide a low cost (1/3 the cost of a comparable minicomputer system), convenient, dedicated, portable system which can be used in a fashion similar to that of portable oscilloscopes. Here, an interface between the Apple computer and CAMAC which is now being used to study the detector for a Cerenkov ring-imaging device is described. The Apple is particularly well-suited to this application because of its ease of use, hi-resolution graphics, peripheral bus and documentation support.
Date: April 1, 1981
Creator: Oxoby, G. J.; Trang, Q. H. & Williams, S. H.
System: The UNT Digital Library
Characterization of the selective reduction of NO by NH/sub 3/ (open access)

Characterization of the selective reduction of NO by NH/sub 3/

The selective reduction of NO by NH/sub 3/ addition has been studied in a lean-burning oil-fired laboratory combustion tunnel as a function of equivalence ratio, NH/sub 3/ injection temperature, concentration of NH/sub 3/ added, and the source of NO. Ammonia breakthrough was found to depend strongly on the NH/sub 3/ addition temperature. The total concentration of nitrogen containing species other N/sub 2/, NO, and NH/sub 3/ was measured with a variety of techniques and was found to be less than 5 ppM over the range of conditions studied.
Date: April 1, 1981
Creator: Lucas, D. & Brown, N.J.
System: The UNT Digital Library
Comparison of LMFBR piping response obtained using response spectrum and time history methods (open access)

Comparison of LMFBR piping response obtained using response spectrum and time history methods

The dynamic response to a seismic event is calculated for a piping system using a response spectrum analysis method and two time history analysis methods. The results from the analytical methods are compared to identify causes for the differences between the sets of analytical results. Comparative methods are also presented which help to gain confidence in the accuracy of the analytical methods in predicting piping system structure response during seismic events.
Date: April 1, 1981
Creator: Hulbert, G. M.
System: The UNT Digital Library
Concrete-polymer composites: current status and future research needs (open access)

Concrete-polymer composites: current status and future research needs

When plastics are combined with mixtures of inorganic materials, high-strength, durable, fast-setting composites are produced. These materials are used in structural engineering and other applications, and as a result of the successes obtained to date, considerable research and development work is in progress throughout the world. One family of polymer-based composites receiving considerable attention is the concrete-polymer materials. Work in this area is directed toward developing new high-strength durable materials by combining cement and concrete technology with that of polymer chemistry. In addition to the significant property enhancement, many combinations of siliceous materials with polymers require lower energy inputs per unit of performance than either component alone.
Date: April 1, 1981
Creator: Kukacka, L. E.
System: The UNT Digital Library
Daily radiation model for use in the simulation of passive solar buildings (open access)

Daily radiation model for use in the simulation of passive solar buildings

A model is presented to characterize solar radiation with just three input parameters for each day. This compressed daily radiation data may be used in place of hourly data in simulations of passive solar buildings. This method is tested with the SUNCAT passive simulation. Global horizontal and direct normal radiation data are input using the compressed daily form instead of by hour. Simulation results are found to be comparable to results based on hourly radiation data.
Date: April 1, 1981
Creator: Sillman, S. & Wortman, D.
System: The UNT Digital Library
Diffusion of solar innovations through television news programming (open access)

Diffusion of solar innovations through television news programming

The rationale, methodology, finished product, and evaluation of a series of short, topical films of various solar applications are presented. They were produced for use on prime-television news programming.
Date: April 1, 1981
Creator: Shoemaker, F.; Halacy, D.; O'Keefe, G.J. & Sendroy, C.G.
System: The UNT Digital Library
Educating the design professional: energy-conscious design for commercial buildings (open access)

Educating the design professional: energy-conscious design for commercial buildings

The energy problem in a residence is substantially different from that in a commercial building; therefore, the approach to using renewable resources in a commercial building differs from that in a residence. For this reason, educational materials, seminars, and workshops developed to teach architects and engineers basic design principles to integrate renewable energy into commercial buildings must differ from that developed for residential building designers. The purpose of this paper is to identify some of the differences in approach between residential and commercial solar design, discuss what the Solar Energy Research Institute (SERI) Commercial Buildings Group has learned about educating commercial building design professionals through experience, and describe the American Institute of Architects (AIA) national effort to educate architects about energy-conscious design.
Date: April 1, 1981
Creator: Carlisle, N. & Franta, G.
System: The UNT Digital Library
Equations of state for strongly nonideal fluid mixtures: application of the local-composition concept (open access)

Equations of state for strongly nonideal fluid mixtures: application of the local-composition concept

A new model has been developed for calculation of fluid-phase equilibria of asymmetric mixtures. This local-composition model extends the quasi-chemical theory of Guggenheim (known to correlate well liquid-state activity coefficients) to fluids of all densities. The model can be applied to any equation of state, contains only one new adjustable parameter per binary pair, and can be extended to multicomponent mixtures of large and small molecules by use of the surface areas of the molecules. Although the local-composition model is a nonrandomness approach, all randomness boundary conditions are met. Significant improvement over the random-mixing model is shown for the prediction of vapor-liquid equilibria of methane/water and ethane/water systems.
Date: April 1, 1981
Creator: Whiting, W.B. & Prausnitz, J.M.
System: The UNT Digital Library
Equipment for drilling miniature holes (open access)

Equipment for drilling miniature holes

Miniature holes are produced on 16 different types of mechanical drilling equipment. Each equipment type has significant advantages for a specific type of part. The basic capabilities vary greatly between equipment types. Some produce very precise holes and others produce very high volumes of commercial tolerance holes. At the present time machines are available for mechanicaly drilling up to 100,000 miniature holes per hour. Lasers currently are drilling as many as 15,000,000 ultra-miniature holes per hour.
Date: April 1, 1981
Creator: Gillespie, L K
System: The UNT Digital Library