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Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems (open access)

Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems

A Photovoltaic Metallization Research Forum, under the sponsorship of the Jet Propulsion Laboratory's Flat-Plate Solar Array Project and the US Department of Energy, was held March 16-18, 1983 at Pine Mountain, Georgia. The Forum consisted of five sessions, covering (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques and (5) future metallization challenges. Twenty-three papers were presented.
Date: November 15, 1983
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Studies on transition metals and alloy Fischer-Tropsch catalysts, their electronic and bulk properties. (I: Fe/MnO; II: Fe/TiO/sub 2/; III: Fe/Mord. ). Final report, July 1, 1982-September 30, 1983 (open access)

Studies on transition metals and alloy Fischer-Tropsch catalysts, their electronic and bulk properties. (I: Fe/MnO; II: Fe/TiO/sub 2/; III: Fe/Mord. ). Final report, July 1, 1982-September 30, 1983

The objectives were: (1) to characterize samples D1, 10% FeO/90% MnO, and D2, 48% FeO/52% MnO, under varying conditions of reduction (at 250/sup 0/C or 350/sup 0/C in H/sub 2/) and of syngas reaction 1:1 of CO:H/sub 2/ at 290/sup 0/C) and in some cases use CO only for reduction and to identify species by Moessbauer Spectroscopy and Magnetization (sigma/sub s) measurement; (2) similarly, to see if there is any metal (oxide)/support (Mordenite) interaction by the same techniques. The characterization was carried out with above techniques and the kinetic results for syngas were obtained on the above systems mostly at PETC. During reduction of Fe-oxide/Mn-oxide an intermediate Mn-ferrite phase was detected. After reduction, species such as Fe/sup 0/+Fe/sup 3 +/+Fe/sup 2 +/ in varying total proportions (45% at 290/sup 0/C and Fe/sup 0/+Fe/sup 2 +/ 75% were found at 350/sup 0/C). Syngas conversion showed Fe-carbides (Fe/sub 2/C/sub 2/+Fe/sub 3/C) depending on the reaction conditions, and the composition of D/sub 1/ and D/sub 2/. With the fresh ..gamma..-Fe/sub 2/O/sub 3/ (identified by Moessbauer) on Mordenites with varying ratios of SiO/sub 2//Al/sub 2/O/sub 3/, a decrease in (sigma/sub s/) was found with lowering of the ratios from 60 to 17. At 17% …
Date: November 1, 1983
Creator: Mulay, L.N.
Object Type: Report
System: The UNT Digital Library
Physical-Chemical Treatment of Tar Sand Processing Wastewater: [Final Report, Tasks 3-5] (open access)

Physical-Chemical Treatment of Tar Sand Processing Wastewater: [Final Report, Tasks 3-5]

The dewatering properties of residuals generated by flotation/foam fractionation treatment of TS-1S wastewater were evaluated. The leachate potential was studied for both chemical coagulation and flotation/foam fractionation sludges. A preliminary economic analysis was made comparing selected sludge disposal options and summarizing previously reported economic analysis of the chemical treatment alternatives.
Date: November 1983
Creator: King, Paul H.
Object Type: Report
System: The UNT Digital Library
Two-stage process for conversion of synthesis gas to high quality transportation fuels. Quarterly report, 8 June-30 September 1983 (open access)

Two-stage process for conversion of synthesis gas to high quality transportation fuels. Quarterly report, 8 June-30 September 1983

The design of two large hot-flow models, to be used for slurry bubble-column hydrodynamic studies, is described. Scoping experiments were performed in smaller models to study the effects of feed-gas distributor type, column diameter, and liquid medium on gas holdup and bubble sizes. In addition, a literature review of bubble-column hydrodynamics is presented. Modifications to improve the operation and flexibility of the existing two stage pilot plant have been designed and construction initiated. Also, a sample of reactor-wax was fractionated under vacuum in a laboratory still. 8 figures, 4 tables.
Date: November 1, 1983
Creator: Kuo, J.C.W.
Object Type: Report
System: The UNT Digital Library
Ultrafast gated intensifier design for laser fusion x-ray framing applications (open access)

Ultrafast gated intensifier design for laser fusion x-ray framing applications

A major challenge for laser fusion is the study of the symmetry and the hydrodynamic stability of imploding fuel capsules. Streaked x-radiography, in one space and one time dimension, does not provide sufficient information. Two (spatial) dimensional frames of 10 to 100 ps duration are required with good image quality, minimum geometrical distortion (approximately 1%), dynamic range greater than 1000 and greater than 200 x 200 pixels. A gated transmission line imager (TLI) can meet these requirements with frame times between 30 and 100 ps. An instrument of this type is now being developed. Progress on this instrument including theory of operation, ultrafast pulse generation and propagation, component integration, and high resolution phosphor screen development are presented.
Date: November 1, 1983
Creator: Price, R.H.; Wiedwald, J.D.; Kalibjian, R.; Thomas, S.W. & Cook, W.M.
Object Type: Article
System: The UNT Digital Library
MFTF-B quasi-optical ECRH transmission system (open access)

MFTF-B quasi-optical ECRH transmission system

The microwave transmission system for ERCH on MFTF-B will utilize quasi-optical transmission techniques. The system consists of ten gyrotron oscillators: two gyrotrons at 28 GHz, two at 35 GHz, and six at 56 GHz. The 28 and 35 GHz gyrotrons both heat the electrons in the end plug (potential peak) while the 56 GHz sources heat the minimum-B anchor region (potential minimum). Microwaves are launched into a pair of cylindrical mirrors that form a pseudo-cavity which directs the microwaves through the plasma numerous times before they are lost out of the cavity. The cavity allows the microwave beam to reach the resonance zone over a wide range of plasma densities and temperatures. The fundamental electron cyclotron resonance moves to higher axial positions as a result of beta-depression of the magnetic field, doppler shifting of the resonance, and relativistic mass corrections for the electrons. With this system the microwave beam will reach the resonance surface at the correct angle of incidence for any density or temperature without active aiming of the antennas. The cavity also allows the beam to make multiple passes through the plasma to increase the heating efficiency at low temperatures and densities when the single pass absorption is …
Date: November 7, 1983
Creator: Yugo, J. J.; Shearer, J. W. & Ziolkowski, R. W.
Object Type: Article
System: The UNT Digital Library
Geothermal Progress Monitor. System status and operational experience (open access)

Geothermal Progress Monitor. System status and operational experience

The Geothermal Progress Monitor (GPM) system was designed and implemented by MITRE for DOE's Division of Geothermal Energy (now the Division of Geothermal and Hydropower Technologies). This report summarizes MITRE's operational experience with the system during fiscal year 1983 and provides a qualitative assessment of its data sources.
Date: November 1, 1983
Creator: Gerstein, R.E. & Medville, D.M.
Object Type: Report
System: The UNT Digital Library
Mark III results from SPEAR (open access)

Mark III results from SPEAR

First results from the MARK III detector at SPEAR are presented based on 2.7 million J/psi decays. The eta/sub c/ is observed in three modes, J/psi ..-->.. ..gamma..eta/sub c/, (eta/sub c/ ..-->.. rho anti rho, eta..pi../sup +/..pi../sup -/, and phi phi). Using the phi phi mode, the eta/sub c/ spin-parity is determined to be 0/sup -/. The known radiative J/psi decays J/psi ..-->.. ..gamma..f(f ..-->.. ..pi../sup +/..pi../sup -/), ..gamma..eta'(eta' ..-->.. ..gamma..rho/sup 0/, eta..pi../sup +/..pi../sup -/), ..gamma..f'(f' ..-->.. kappa/sup +/kappa/sup -/), ..gamma..theta(theta ..-->.. kappa anti kappa), and ..gamma..iota(iota ..-->.. ..pi..kappa anti kappa) are observed and their branching ratios found to be in agreement with previous measurements. In the J/psi ..-->.. ..gamma..kappa/sup +/kappa/sup -/ mode a new state is observed at 2.22 GeV and in the J/psi ..-->.. ..gamma gamma..rho/sup 0/ and ..gamma..eta..pi../sup +/..pi../sup -/ modes evidence for new structures near 1.4 GeV is presented. 29 references.
Date: November 1, 1983
Creator: Toki, W.
Object Type: Report
System: The UNT Digital Library
Relationship of regional water quality to aquifer thermal energy storage (open access)

Relationship of regional water quality to aquifer thermal energy storage

Ground-water quality and associated geologic characteristics may affect the feasibility of aquifer thermal energy storage (ATES) system development in any hydrologic region. This study sought to determine the relationship between ground-water quality parameters and the regional potential for ATES system development. Information was collected from available literature to identify chemical and physical mechanisms that could adversely affect an ATES system. Appropriate beneficiation techniques to counter these potential geochemical and lithologic problems were also identified through the literature search. Regional hydrology summaries and other sources were used in reviewing aquifers of 19 drainage regions in the US to determine generic geochemical characteristics for analysis. Numerical modeling techniques were used to perform geochemical analyses of water quality from 67 selected aquifers. Candidate water resources regions were then identified for exploration and development of ATES. This study identified six principal mechanisms by which ATES reservoir permeability may be impaired: (1) particulate plugging, (2) chemical precipitation, (3) liquid-solid reactions, (4) formation disaggregation, (5) oxidation reactions, and (6) biological activity. Specific proven countermeasures to reduce or eliminate these effects were found. Of the hydrologic regions reviewed, 10 were identified as having the characteristics necessary for ATES development: (1) Mid-Atlantic, (2) South-Atlantic Gulf, (3) Ohio, (4) …
Date: November 1, 1983
Creator: Allen, R.D.
Object Type: Report
System: The UNT Digital Library
Volume H/sup -/ ion production experiments at LBL (open access)

Volume H/sup -/ ion production experiments at LBL

H/sup -/ ions formed by volume processes have been extracted from a multicusp ion source. It is shown that a permanent magnet filter together with a small positive bias voltage on the plasma grid can produce a very significant reduction in electron drain as well as a sizable increase in H/sup -/ ions available for extraction. A further reduction in electron current is achieved by installing a pair of small magnets at the extraction aperture. An H/sup -/ ion current density of 38 mA/cm/sup 2/ was obtained with a discharge current of approximately 350 A. Different techniques to increase the H/sup -/ ion yield have also been investigated.
Date: November 1, 1983
Creator: Leung, K. N. & Ehlers, K. W.
Object Type: Article
System: The UNT Digital Library
Recent Results From DELCO (open access)

Recent Results From DELCO

DELCO is a magnetic spectrometer with Cerenkoc, Time-of-Flight (TOF) and shower counters for particle identification. It is located in IR8 of the PEP storage ring. Data have been obtained at a center of mass energy, ..sqrt..s, of 29 GeV. We report on: (1) the fraction of P, K, ..pi.. in hadronic events; (2) the observation of direct electron signals; and (3) the measurement of D* fragmentation function and its total cross-section. 8 references.
Date: November 1, 1983
Creator: Atwood, W. B.; Baillon, P. H.; Barish, B. C.; Bonneaud, G. R.; DeStaebler, H.; Donaldson, G. J. et al.
Object Type: Report
System: The UNT Digital Library
Tritium related safety considerations for mirror upgrades (open access)

Tritium related safety considerations for mirror upgrades

One of the primary objectives of the MFTF-B upgrades is to demonstrate the technology of tritium breeding in a reactor-like configuration. This requires use and processing of tritium, involving an inventory of several hundred grams at the plant. This paper reviews the results of a preliminary assessment of the radiation hazard associated with the handling of tritium. The radiation dose consequences due to tritium release from normal operation and due to postulated accidents on plant personnel and the public were assessed. Maximum credible (probability < 10/sup -3/, but > 10/sup -7//yr) accidental releases were estimated to be 10 gm in the reactor building and 100 gm in the tritium-processing building. Higher probability (> 10/sup -3//yr) accidents or component failures would result in much smaller releases. In the reactor building, the most severe accident would result from the rupture of a plasma exhaust duct from the end cell or the tritium feed pipe to the neutral beam injector, accompanied by a fire. In the tritium processing building, the most severe accident would be the rupture of the Isotope Separation System (ISS) distillation columns and vacuum jackets accompanied by a fire.
Date: November 30, 1983
Creator: Ghose, S.K.
Object Type: Article
System: The UNT Digital Library
Status of greater than or equal to 1 ampere H/sup -/ ion source development at the Lawrence Berkeley Laboratory (open access)

Status of greater than or equal to 1 ampere H/sup -/ ion source development at the Lawrence Berkeley Laboratory

This paper summarizes the effort to improve the operation of the approx. 1 A surface-production H/sup -/ ion source developed by K.W. Ehlers and K.N. Leung. The plasma chamber consists of a large magnetic bucket of oval cross section. A concave cylindrical converter surface is suspended in the plasma chamber to direct any surface-produced negative ions through the exit aperture. The ion source has been mated to a tetrode accelerator for the proof-of-principle tests. Most of the problems discovered in the tests were associated with difficulties in controlling the production process. This paper describes the plasma chamber in greater detail and illustrates the quality of the presnet ion production. The acceleration difficulties have been deferred until a better test-stand is completed.
Date: November 1, 1983
Creator: Lietzke, A. F.; Ehlers, K. W. & Leung, K. N.
Object Type: Article
System: The UNT Digital Library
Technical specifications - enhancing the safety impact (open access)

Technical specifications - enhancing the safety impact

This report documents the work of an interoffice, interdisciplinary, NRC Task Group established in August 1983 to identify the scope and nature of problems with surveillance testing in current Technical Specifications and to develop alternative approaches that will provide better assurance that surveillance testing does not adversely impact safety. The Task Group concluded that some of the Technical Specifications have the potential for adversely affecting safety and some do not appear to be cost effective. The Task Group developed five recommendations for improvement. 15 references.
Date: November 1, 1983
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Ion-induced surface modification of alloys (open access)

Ion-induced surface modification of alloys

In addition to the accumulation of the implanted species, a considerable number of processes can affect the composition of an alloy in the surface region during ion bombardment. Collisions of energetic ions with atoms of the alloy induce local rearrangement of atoms by displacements, replacement sequences and by spontaneous migration and recombination of defects within cascades. Point defects form clusters, voids, dislocation loops and networks. Preferential sputtering of elements changes the composition of the surface. At temperatures sufficient for thermal migration of point defects, radiation-enhanced diffusion promotes alloy component redistribution within and beyond the damage layer. Fluxes of interstitials and vacancies toward the surface and into the interior of the target induce fluxes of alloying elements leading to depth-dependent compositional changes. Moreover, Gibbsian surface segregation may affect the preferential loss of alloy components by sputtering when the kinetics of equilibration of the surface composition becomes competitive with the sputtering rate. Temperature, time, current density and ion energy can be used to influence the individual processes contributing to compositional changes and, thus, produce a rich variety of composition profiles near surfaces. 42 references.
Date: November 1, 1983
Creator: Wiedersich, H.
Object Type: Article
System: The UNT Digital Library
Interpretation of interference data from the Klamath Falls, Oregon geothermal resource (open access)

Interpretation of interference data from the Klamath Falls, Oregon geothermal resource

Data from a seven week pressure interference test in the Klamath Falls, Oregon geothermal resource have been analyzed. The data indicate that productive wells are fed by a highly permeable fracture network and that the less permeable matrix blocks contribute significantly to the reservoir storage capacity. Detailed analysis of data from two wells is presented. Data from both of the wells yield a reservoir permeability-thickness (kh) of approximately 1.3x10/sup 6/ md-ft and a storativity (phi c/sub t/h) of 6.8x10/sup -3/ ft/psi. The parameters (lambda and ..omega..), which are determined by the distribution of permeability and storativity between the matrix and fractures, vary by more than an order of magnitude. A sensitivity study shows that for these wells, the pressure transients are not very sensitive to the distribution of permeability and storativity between the fractures and matrix blocks. No hydrologic boundaries were detected during the test. This indicates that the fault which supplies hot water to the shallow hydrothermal system does not behave according to the classical model of either a barrier or constant potential boundary.
Date: November 1, 1983
Creator: Benson, S.M.
Object Type: Article
System: The UNT Digital Library
Brief summary of staffing levels at Fermilab during initial construction years (open access)

Brief summary of staffing levels at Fermilab during initial construction years

This paper very briefly summarizes the work of the various groups that were involved from the beginning through the end of the initial construction phase of the Fermilab project (defined here to be July 1, 1972) and the final construction or completion phase which is here defined as December 31, 1973. The numbers in this report have been gathered by examining the personnel records of Fermilab with the research being done by Chuck Marofske, the Head of Laboratory Services and his staff and by assembling information from the memories of people still with the laboratory in 1983. Since there was much mobility within the laboratory during the construction years and frequent reorganizations were the norm, the numbers presented herein can not be considered to be more accurate than about +- 5%.
Date: November 1, 1983
Creator: Livdahl, P.V.
Object Type: Report
System: The UNT Digital Library
Auger decay mechanism in photon-stimulated desorption of ions from surfaces (open access)

Auger decay mechanism in photon-stimulated desorption of ions from surfaces

Photon-stimulated desorption (PSD) of positive ions was studied with synchrotron radiation using an angle-integrating time-of-flight mass spectrometer. Ion yields as functions of photon energy near core levels were measured from condensed gases, alkali fluorides, and other alkali and alkaline earth halides. These results are compared to bulk photoabsorption measurements with emphasis on understanding fundamental desorption mechanisms. The applicability of the Auger decay mechanism, in which ion desorption is strictly proportional to surface absorption, is discussed in detail. The Auger decay model is developed in detail to describe Na/sup +/ and F/sup +/ desorption from NaF following Na(1s) excitation. The major decay pathways of the Na(1s) hole leading to desorption are described and equations for the energetics of ion desorption are developed. Ion desorption spectra of H/sup +/, Li/sup +/, and F/sup +/ are compared to bulk photoabsorption near the F(2s) and Li(1s) edges of LiF. A strong photon beam exposure dependence of ion yields from alkali fluorides is revealed, which may indicate the predominance of metal ion desorption from defect sites. The large role of indirect mechanisms in ion desorption condensed N/sub 2/-O/sub 2/ multilayers is demonstrated and discussed. Ion desorption spectra from several alkali halides and alkaline earth halides …
Date: November 1, 1983
Creator: Parks, C.C.
Object Type: Report
System: The UNT Digital Library
Some nitrogen-14 NMR studies in solids (open access)

Some nitrogen-14 NMR studies in solids

The first order quadrupolar perturbation of the /sup 14/N NMR spectrum yields information regarding the static and dynamic properties of the surrounding electronic environment. Signal to noise problems caused by long /sup 14/N longitudinal relaxation times (T/sub 1/) and small equilibrium polarizations are reduced by rotating frame cross polarization (CP) experiments between /sup 14/N and /sup 1/H. Using quadrupolar echo and CP techniques, the /sup 14/N quadrupolar coupling constants (e/sup 2/qQ/h) and asymmetry parameters (eta) have been obtained for a variety of tetraalkylammonium compounds by observation of their quadrupolar powder patterns at various temperatures. For choline chloride and iodide the /sup 14/N NMR powder patterns exhibit the effects of anisotropic molecular motion, while choline bromide spectra show no such effects.
Date: November 1, 1983
Creator: Pratum, T. K.
Object Type: Report
System: The UNT Digital Library
NOVA laser facility for inertial confinement fusion (open access)

NOVA laser facility for inertial confinement fusion

The NOVA laser consists of ten beams, capable of concentrating 100 to 150 kJ of energy (in 3 ns) and 100 to 150 TW of power (in 100 ps) on experimental targets by 1985. NOVA will also be capable of frequency converting the fundamental laser wavelength (1.05 ..mu..m) to its second (0.525 ..mu..m) or third (0.35 ..mu..m) harmonic. This additional capability (80 to 120 kJ at 0.525 ..mu..m, 40 to 70 kJ at 0.35 ..mu..m) was approved by the US Department of Energy (DOE) in April 1982. These shorter wavelengths are much more favorable for ICF target physics. Current construction status of the NOVA facility, intended for completion in the autumn of 1984, will be presented.
Date: November 30, 1983
Creator: Simmons, W.W.
Object Type: Article
System: The UNT Digital Library
Magnet power control system for the Tandem Mirror Experiment-Upgrade (open access)

Magnet power control system for the Tandem Mirror Experiment-Upgrade

This paper describes the desktop computer/CAMAC-based system that controls the power source for the Tandem Mirror Experiment-Upgrade (TMX-U) magnet power system. Presently it contains 42 dc rectifier power supplies connected to 24 magnet coils arranged in 17 circuits. During each shot, the system delivers 22.6 MW dc to the magnets for about 3 s. The system is presently being changed to add six power supplies, two solenoidal throttle coils, and two reverse C-coils. When complete, the delivered power will increase to 36.9 MW. The closed-loop control system usually provides current (and thus, magnetic field) that is within 1% of the requested current. Achieving this accuracy required using grounding, shielding, and isolation methods to reduce noise and related problems. These are also discussed.
Date: November 4, 1983
Creator: Bell, H.H. Jr.
Object Type: Article
System: The UNT Digital Library
Energy and technology review (open access)

Energy and technology review

Separate abstracts were prepared for three papers in this review. (LEW)
Date: November 1, 1983
Creator: unknown
Object Type: Report
System: The UNT Digital Library
TFTR initial operations (open access)

TFTR initial operations

The Tokamak Fusion Test Reactor (TFTR) has operated since December 1982 with ohmically heated plasmas. Routine operation with feedback control of plasma current, position, and density has been obtained for plasmas with I/sub p/ approx. = 800 kA, a = 68 cm, R = 250 cm, and B/sub t/ = 27 kG. A maximum plasma current of 1 MA was achieved with q approx. = 2.5. Energy confinement times of approx. 150 msec were measured for hydrogen and deuterium plasmas with anti n/sub e/ approx. = 2 x 10/sup 13/ cm/sup -3/, T/sub e/ (0) approx. = 1.5 keV, T/sub i/ (0) approx. = 1.5 keV, and Z/sub eff/ approx. = 3. The preliminary results suggest a size-cubed scaling from PLT and are consistent with Alcator C scaling where tau approx. nR/sup 2/a. Initial measurements of plasma disruption characteristics indicate current decay rates of approx. 800 kA in 8 ms which is within the TFTR design requirement of 3 MA in 3 ms.
Date: November 1, 1983
Creator: Young, K.M.; Bell, M.; Blanchard, W.R.; Bretz, N.; Cecchi, J.; Coonrod, J. et al.
Object Type: Report
System: The UNT Digital Library
Initial characterization of a BGO-photodiode detector for high resolution positron emission tomography (open access)

Initial characterization of a BGO-photodiode detector for high resolution positron emission tomography

Spatial resolution in positron emission tomography is currently limited by the resolution of the detectors. This work presents the initial characterization of a detector design using small bismuth germanate (BGO) crystals individually coupled to silicon photodiodes (SPDs) for crystal identification, and coupled in groups to phototubes (PMTs) for coincidence timing. A 3 mm x 3 mm x 3 mm BGO crystal coupled only to an SPD can achieve a 511 keV photopeak resolution of 8.7% FWHM at -150/sup 0/C, using a pulse peaking time of 10 ..mu..s. When two 3 mm x 3 mm x 15 mm BGO crystals are coupled individually to SPDs and also coupled to a common 14 mm diam PMT, the SPDs detect the 511 keV photopeak with a resolution of 30% FWHM at -76/sup 0/C. In coincidence with an opposing 3 mm wide BGO crystal, the SPDs are able to identify the crystal of interaction with good signal-to-noise ratio, and the detector pair resolution is 2 mm FWHM. 32 references, 7 figures, 3 tables.
Date: November 1, 1983
Creator: Derenzo, S.E.
Object Type: Article
System: The UNT Digital Library