113 research outputs found
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The Ahuachapan geothermal field, El Salvador: Reservoir analysis
These are appendices F through I of the Ahuachapan Geothermal Field Reservoir Analysis. The volume contains: well logs, water chemistry plots, gas chemistry plots, temperature plots, and flow plots. (JEF
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Fundamental sputtering studies: Nonresonant ionization of sputtered neutrals
Because of the practical importance of sputtering, numerous theories and computer simulations are used for predicting many aspects of the sputtering process. Unfortunately, many of the calculated sputtering results are untested by experiment. Until recently, most sputtering experiments required either very high ion fluences or the detection of only minor constituents of the sputtered flux, i.e., ions. These techniques may miss the subtleties involved in the sputtering process. High-detection-efficiency mass spectrometry, coupled with the laser ionization of neutral atoms, allows the detection of the major sputtered species with very low incident ion fluences. The depth-of-origin of sputtered atoms is one example of an important but poorly understood aspect of the sputtering process. By following the sputtering yield of a substrate atom with various coverages of an adsorbed overlayer, the depth of origin of sputtered atoms has been determined. Our results indicate that two-thirds of the sputtered flux originates in the topmost atomic layer. The ion-dose dependence of sputtering yields has long been assumed to be quite minor for low- to-moderate primary ion fluences. We have observed a two-fold decrease in the sputtering yield of the Ru(0001) surface for very low primary ion fluences. Data analysis results in a cross section for damage of 2.7 {plus minus} 1.0 {times} 10{sup {minus}15}cm{sup 2}. 40 refs., 3 figs., 2 tabs
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USA/CIS coordinating committee and its hydrologic studies
The United States and the former Soviet Union (now the Commonwealth of Independent States) have set up the Joint Coordinating Committee on Civilian Nuclear Reactor Safety (JCCCNRS) to enhance safe operation of civilian nuclear reactors. The agreement contains Section 7.1, Environmental Transport,'' and Section 7.2 Health Impacts.'' Main objectives of the programs under JCCCNRS are to test and improve methodologies, mathematical models, technologies, and techniques need to understand and to more accurately forecast radionuclide behavior in the environment following nuclear power plant accidents. These programs currently focus on problems from the Chernobyl Nuclear Power Plant accident. This paper describes the activities of Program 7.1.F
Toward a Multifaceted Heuristic of Digital Reading to Inform Assessment, Research, Practice, and Policy
In this commentary, the author explores the tension between almost 30 years of work that has embraced increasingly complex conceptions of digital reading and recent studies that risk oversimplifying digital reading as a singular entity analogous with reading text on a screen. The author begins by tracing a line of theoretical and empirical work that both informs and complicates our understanding of digital literacy and, more specifically, digital reading. Then, a heuristic is proposed to systematically organize, label, and define a multifaceted set of increasingly complex terms, concepts, and practices that characterize the spectrum of digital reading experiences. Research that informs this heuristic is used to illustrate how more precision in defining digital reading can promote greater clarity across research methods and advance a more systematic study of promising digital reading practices. Finally, the author discusses implications for assessment, research, practice, and policy
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Tests of Fermilab built 40 mm aperture full length SSC dipole magnets
Several 40 mm aperture, 17 m long dipoles have been built by Fermilab as developmental prototypes for the Superconducting Super Collider. These magnets differ from those manufactured at Brookhaven National Laboratory in that they have an external inner-outer coil splice design, a collet style end clamp assembly, a new, analytically designed minimum stress coil end design, and a new insulation system which does not employ shims or shoes''. In addition, the magnets were built using production-style tooling. The magnets were tested at the Fermilab Magnet Testing Facility. Quench testing and mechanical measurement results are presented and analyzed with emphasis on the new design and fabrication features of these magnets. 13 refs., 5 figs
Activities report in space tribology
SIGLEAvailable from British Library Document Supply Centre- DSC:6015.42F(N--87-12005)(microfiche) / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Air photographs for investigating natural changes, past use and present condition of engineering sites
SIGLELD:9057.24(TRRL-LR--1085) / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Public transport in Kingston, Jamaica and its relation to low income households
SIGLELD:6413.35F(PB--81-108664)(microfiche) / BLDSC - British Library Document Supply CentreGBUnited Kingdo
On the use of element-by-element preconditioners to solve large scale partially separable optimization problems
SIGLEAvailable from British Library Document Supply Centre- DSC:8053.4153(RAL--95-010) / BLDSC - British Library Document Supply CentreGBUnited Kingdo
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The search for solid state fusion lasers
Inertial confinement fusion (ICF) research puts severe demands on the laser driver. In recent years large, multibeam Nd:glass lasers have provided a flexible experimental tool for exploring fusion target physics because of their high powers, variable pulse length and shape, wavelength flexibility using harmonic generation, and adjustable that Nd:glass lasers can be scaled up to provide a single-phase, multi-megajoule, high-gain laboratory microfusion facility, and gas-cooled slab amplifiers with laser diode pump sources are viable candidates for an efficient, high repetition rate, megawatt driver for an ICF reactor. In both applications requirements for energy storage and energy extraction drastically limit the choice of lasing media. Nonlinear optical effects and optical damage are additional design constraints. New laser architectures applicable to ICF drivers and possible laser materials, both crystals and glasses, are surveyed. 20 refs., 2 figs
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