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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
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
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
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
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
MHD generator component development. Quarterly report, July 1983-September 1983 (open access)

MHD generator component development. Quarterly report, July 1983-September 1983

The overall objectives of this program are two-fold: (1) To contribute, by appropriate systematic experimental and analytical investigations, to the engineering data base necessary for the design and construction of MHD generators at CDIF-scale (50 MW/sub th/) and baseload scale (2000 MW/sub th/). (2) To design and fabricate specific hardware items to be tested at the CDIF site in Butte, Montana. The program consists of a series of related tasks: (1) MHD channel design and performance; (2) MHD channel construction and lifetime; (3) MHD channel loading and control; (4) facility operation; (5) CDIF related hardware; and (6) high interaction tests of a supersonic channel. Progress is reported. (WHK)
Date: November 1, 1983
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Possibilities for x-ray holography using synchrotron radiation (open access)

Possibilities for x-ray holography using synchrotron radiation

Since the theoretical and experimental demonstrations of the effectiveness of soft x-rays in imaging biological material there has been considerable study given to the prospects for further development of the presently existing techniques. This has been motivated to a large extent by advances in source technology, particularly the use of undulators on electron storage rings and recent improvements in short wavelength lasers. The present author has carried out theoretical evaluations of the possibilities of holographic imaging and has also recorded a number of holograms using the U15 soft x-ray beamline at the National Synchrotron Light Source (NSLS) 750 MeV storage ring at Brookhaven. Some of these have been successfully reconstructed using He:Cd laser light. In this paper we first review the physical processes which generate information containing wavefronts when soft x-rays interact with matter. We then briefly describe the holographic method which has been highly developed using visible light lasers and identify holographic geometries which are promising for x-ray applications. We discuss some of the practical and theoretical limitations involved in making holographic images and then give the results of our own experiments.
Date: November 1, 1983
Creator: Howells, M.R.
Object Type: Report
System: The UNT Digital Library
Considerations involved in the design of negative-ion-based neutral beam systems (open access)

Considerations involved in the design of negative-ion-based neutral beam systems

We consider the requirements and constraints for negative-ion-based neutral beam injection systems, and show how these are reflected in design considerations. We will attempt to develop a set of guidelines for users and developers to use to see how well (in a qualitative sense, at least) a particular neutral beam system fits a particular proposed need.
Date: November 1, 1983
Creator: Cooper, W. S.
Object Type: Article
System: The UNT Digital Library
Heavy ion fusion year-end report, April 1, 1983-September 30, 1983 (open access)

Heavy ion fusion year-end report, April 1, 1983-September 30, 1983

Some highlights of the program during this reporting period are as follows: (1) First results with the completed apparatus of the Single Beam Transport Experiment (SBTE) have shown the stable propagation of a space-charge-dominated cesium-ion beam through 41 periods of an AG focussing lattice. The space-charge effects were large enough to depress the betatron phase advance per cell from sigma/sub 0/ = 60/sup 0/ to sigma = 12/sup 0/. (2) Understanding of the reflection stabilization of longitudinal instability in a high-current beam bunch has been improved by analytical and computational studies. (3) Conceptual design studies of a multiple-beam ion induction linac suitable for the High Temperature Experiment have progressed to the stage where a first reference design (sodium, 125 MeV, 30 ..mu..C, 16 beams) is available. (4) The Long-Pulse Induction Accelerating Unit, first used to accelerate a cesium-ion beam in February 1983, has been undergoing modification in the low-level trigger circuitry to allow more precisely controlled waveform synthesis.
Date: November 1, 1983
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Devitrification behavior of SRL defense waste glass (open access)

Devitrification behavior of SRL defense waste glass

Simulated SRL waste was prepared with compositions varying in iron and aluminum content. Two batches with similar composition were produced with different amounts of reducing agent added. Samples were isothermally heat treated and used to derive time-temperature-transformation diagrams. Supplementary samples were cooled in a manner programmed to simulate the cooling curves of production canisters. Less than 10% total devitrification occurs during normal processing. However, when waste glass 165 was purposely devitrified, up to 30 volume percent total spinel and acmite formed. Formation of these species had minor effect on leachability in MCC-1 and accelerated leach tests. 20 references, 4 figures, 2 tables.
Date: November 1, 1983
Creator: Bickford, Dennis F. & Jantzen, Carol M.
Object Type: Article
System: The UNT Digital Library
Influence of cover defects on the attenuation of radon with earthen covers (open access)

Influence of cover defects on the attenuation of radon with earthen covers

Experimental and theoretical evaluations of radon flux through laboratory-scale defective soil columns are presented together with a survey of literature on the formation and prevention of defects in soil covers. This report focuses on air-filled, centimeter-scale defects that are most probable in earthen covers for attenuating radon emission from uranium-mill tailings. Examples include shirnkage and erosion cracks, erosion piping, animal burrows and air channels formed by the biodegradation of vegetation roots. Calculations based on mathematical models indicate that collections of defects which could increase the radon flux from an earthen cover by a factor of two would be easily detected by visual inspection. However, these models ignore air-turbulence in the defect and drying of the soil around the defect. Laboratory measurements showed that turbulent diffusion of radon occurred through defects as narrow as 0.3 cm when subjected to a transverse air velocity of 1 to 6 miles per hour at the surface. Both turbulence and more-rapid drying of soil can accelerate radon flux to the cover surface. Consequently, recommended methods to inhibit defect formation should be applied. 29 references, 3 figures, 5 tables.
Date: November 1, 1983
Creator: Kalkwarf, D. R. & Mayer, D. W.
Object Type: Report
System: The UNT Digital Library