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Resource capture by single leaves

Description: Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfull… more
Date: May 1, 1992
Creator: Long, S.P.
Partner: UNT Libraries Government Documents Department
open access

Growth, preparation, and dielectric properties of monodomain single crystal PbTiO sub 3

Description: A method is described for obtaining monodomain PbTiO{sub 3} single crystals with high electrical resistivity (10{sup 10}{Omega} cm) and low dielectric frequency dispersion. The single crystals of PbTiO{sub 3} were grown by flux solution method. Space charge related defects, which result in the large dielectric frequency dispersion, were eliminated by heat treatments. 90{degrees} domains were removed by applying a unidirectional compressive stress along the <100> crystallographic direction. The … more
Date: May 1, 1992
Creator: Li, Z.; Xu, X. Z.; Dai, X. H.; Lam, D. J. & Chan, S. K.
Partner: UNT Libraries Government Documents Department
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The use of synchrotron radiation for the analysis of coal combustion products

Description: An understanding of the chemical composition of such slags under boiler operating conditions and as function of the mineral composition of various coals is the ultimate goal of this program. The experiment involves scanning through the K- or L-shell absorption edge of the element in question. The structure of the absorption edge, consisting of transitions to unoccupied molecular levels, can be compared to those of model compounds for identification. The relative position of the absorption edge … more
Date: May 1, 1992
Creator: Manowitz, B. & Gordon, B.
Partner: UNT Libraries Government Documents Department
open access

Recent experimental studies on Hadron showers produced in high energy muon-nucleus interactions

Description: The Fermilab Tevatron Muon Experiment has analyzed the hadron showers of events resulting from the scattering of a muon beam (< E{sub {mu}} > = 490 GeV) off H{sub 2}, D{sub 2} and Xenon targets. The topics which will be discussed are: (1) space-time evolution of the hadronization process; (2) leading hadron distributions in the shadowing region; (3) rates and characteristics of 3-jet events. 23 refs.
Date: May 1, 1992
Creator: Morfin, J.
Partner: UNT Libraries Government Documents Department
open access

Conduct of operations: The foundation of safety -- An overview

Description: This paper discusses issues and approaches dealing with conceptualizing, implementing, and maintaining configuration control commensurate with the conduct of operations approach defined by DOE ORDER 5480.19. Specific topics reviewed will include key elements of assessments to determine the status quo such as assessment criteria, assessment personnel, and assessment scope; administrative programs to maintain the status quo such as organizational definition, responsibilities, interfaces, and prio… more
Date: May 1, 1992
Creator: Willett, D.J. & Hertel, N.E.
Partner: UNT Libraries Government Documents Department
open access

Static magnetic fields: A summary of biological interactions, potential health effects, and exposure guidelines

Description: Interest in the mechanisms of interaction and the biological effects of static magnetic fields has increased significantly during the past two decades as a result of the growing number of applications of these fields in research, industry and medicine. A major stimulus for research on the bioeffects of static magnetic fields has been the effort to develop new technologies for energy production and storage that utilize intense magnetic fields (e.g., thermonuclear fusion reactors and superconduct… more
Date: May 1, 1992
Creator: Tenforde, T.S.
Partner: UNT Libraries Government Documents Department
open access

Superconducting final focus for the SLAC Linear Collider

Description: Triplets composed of superconducting quadrupoles have been built and installed as the final focusing element for the high-energy positron and electron beams of the SLAC Linear Collider. Special features include independent alignment to 100-micron tolerance inside a common cryostat; non-magnetic materials to allow operation inside the detector's solenoid field; a continuous-flow helium-only system using 50-meter-long flexible transfer lines; and complete operation of the system before installati… more
Date: May 1, 1992
Creator: Ash, W.W.; Barrera, F.; Burgess, W.; Cook, K.; Cutler, H.; Ferrie, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Krakow Clean Fossil Fuels and Energy Efficiency Project

Description: In Karkow, Poland almost half of the energy used for heating is supplied by local, solid-fuel-fired boilerhouses and home stoves. These facilities are referred to as the low emission sources'' and are primary contributors of particulates and hydrocarbon air pollution in the city and secondary contributors of sulfur dioxide and carbon monoxide. The Support of Eastern European Democracy Act of 1989 directed the US Department of Energy to undertake an equipment assessment project aimed at developi… more
Date: May 1, 1992
Creator: Butcher, T.A.; Pierce, B.; Krajewski, R.; LaMontagne, J. & Kirchstetter, T.
Partner: UNT Libraries Government Documents Department
open access

Optimization of a VISAR for measuring flyer-plate velocities

Description: VISAR (Velocity Interferometer System for Any Reflector) is commonly used for measuring flyer-plate velocities up to 6 km/s. Flyer plates can travel as much as 1 mm, which is large compared to usual depth-of-focus requirements for VISARs. Flyer plates are explosively driven, or driven by some other very energetic means; as such, they must be tested in a chamber, which will contain the explosion. Routing the laser beam to the chamber and the signal beam to the VISAR can be done safely and easily… more
Date: May 6, 1992
Creator: Sweatt, W. C.; Crump, O. B., Jr. & Brigham, W. P.
Partner: UNT Libraries Government Documents Department
open access

Audit unto others hor ellipsis

Description: My first encounter with a quality assurance auditor is reminiscent of an old Dodge commercial. You remember The old sheriff, masked in mirrored sunglasses, paunch hanging over his gun belt, prophesying, You're in a heap o' trouble boy '' Well, my auditor could have been kin to the sheriff; they had the same posture, attitude, and mirrored sunglasses. Plus, my auditor wore a black leather vest and sported a Buffalo Bill'' goatee. While certainly memorable, both gentlemen were far from pleasant. … more
Date: May 1, 1992
Creator: Maday, J.H. Jr.
Partner: UNT Libraries Government Documents Department
open access

MHTGR thermal performance envelopes: Reliability by design

Description: This document discusses thermal performance envelopes which are used to specify steady-state design requirements for the systems of the Modular High Temperature Gas-Cooled Reactor to maximize plant performance reliability with optimized design. The thermal performance envelopes are constructed around the expected operating point accounting for uncertainties in actual plant as-built parameters and plant operation. The components are then designed to perform successfully at all points within the … more
Date: May 1, 1992
Creator: Etzel, K.T.; Howard, W.W. & Zgliczynski, J.B.
Partner: UNT Libraries Government Documents Department
open access

Measurement of radiofrequency fields

Description: We are literally surrounded by radiofrequency (RFR) and microwave radiation, from both natural and man-made sources. The identification and control of man-made sources of RFR has become a high priority of radiation safety professionals in recent years. For the purposes of this paper, we will consider RFR to cover the frequencies from 3 kHz to 300 MHz, and microwaves from 300 MHz to 300 GHz, and will use the term RFR interchangeably to describe both. Electromagnetic radiation and field below 3 k… more
Date: May 1, 1992
Creator: Leonowich, J.A.
Partner: UNT Libraries Government Documents Department
open access

Optimal forced-air distribution in new housing

Description: This paper summarizes a system integration approach to residential heating, cooling, and ventilation, embodied in a tight building envelope with precooling and dehumidification of forced ventilation air, and with ducts in the conditioned space.
Date: May 1, 1992
Creator: Andrews, J. W.
Partner: UNT Libraries Government Documents Department
open access

Writing audit findings: Be reasonable

Description: A customary approach to auditing and reporting deficiencies is to keep a running list of those that are found, evaluate the severity of each, and based on the evidence, document findings or observations or concerns in an audit report. The report is issued and the auditee is normally requested to address root cause'' as part of their corrective action. This paper describes a root problems'' approach to documenting audit findings that is designed not only to put the QA auditor in a more favorable… more
Date: May 1, 1992
Creator: Girvin, N.W.
Partner: UNT Libraries Government Documents Department
open access

Development of nondestructive evaluation methods and prediction of effects of flaws on the fracture behavior of structural ceramics

Description: Characterization of ceramic matrix composites (continuous and whisker-type) by nondestructive evaluation (NDE) methods and an understanding of fracture behavior, together with correlation of fracture and NDE data, may provide insight into the prediction of component performance and the development of process technology. Knowledge of the degradation extent of fiber tows or monofilament degradation after processing, extent of open porosity before densification, and filament/fiber alignments befor… more
Date: May 1, 1992
Creator: Ellingson, W.A.; Singh, J.P.; Holloway, D.L.; Dieckman, S.L.; Singh, D.; Sivers, E.A. et al.
Partner: UNT Libraries Government Documents Department
open access

Sintering of Bulk High - Tc Superconductors: Bi-Sr-Ca-Cu-O

Description: Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (2212) and (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} (2223) superconductors have orthorhombic crystal structures. They form platelike grains that at high temperatures grow primarily in the a-b planes and not in the c direction. The diffusional properties of Bi-Sr-Ca-Cu-O superconductors are so anisotropic that 2212 and 2223 cannot, in general, be densified by solid-state sintering. Improved densification can be achieved by application of pressure or… more
Date: May 1, 1992
Creator: Goretta, K. C.; Lanagan, M. T.; Kaufman, D. Y.; Biondo, A. C.; Wu, C. T.; Loomans, M. E. et al.
Partner: UNT Libraries Government Documents Department
open access

How much will pollution reduction in Krakow cost

Description: This report is on the status of US/Polish efforts to reduce air pollution from low emission sources (coalfired house stoves and local boilers) in Krakow, Poland. The region around Krakow in Southern Poland is one of the most heavily polluted areas in the world. In 1989, while visiting Poland, President George Bush made a commitment on behalf of the US to assist in the reclamation of the Krakow environment; Congress in 1990 authorized $20 million to address pollutants from low emissions sources,… more
Date: May 1, 1992
Creator: LaMontagne, J.; Pierce, B. (Brookhaven National Lab., Upton, NY (United States)) & Gorlich, K. (Ministry of the Environment, Krakow (Poland))
Partner: UNT Libraries Government Documents Department
open access

Impacts of changing residential oil burner technology

Description: This paper presents trends in oil-fired residential heating appliance design that take advantage of recent research which promises significantly lower pollutant emissions, improved performance, and efficiency.
Date: May 1, 1992
Creator: Butcher, T.; McDonald, R.; Krajewski, R.; Celebi, Y. & Andrews, J.
Partner: UNT Libraries Government Documents Department
open access

Catalyst and Feedstock Effects in the Thermochemical Conversion of Biomass to Liquid Transportation Fuels

Description: The thermochemical conversion of biomass feedstocks to liquid transportation fuels can be accomplished by three processes, namely gasification, high-pressure liquefaction, and pyrolysis. In this study, the pyrolysis option is selected which is followed by the catalytic upgrading of pyrolysis vapors to aromatic and olefinic hydrocarbons (PYROCAT process). The aromatics constitute a high-octane gasoline blend, while the olefins can be utilized as feedstocks for various chemicals. The PYROCAT proc… more
Date: May 1992
Creator: Rejai, B.; Agblevor, F. A.; Evans, R. J. & Wang, D.
Partner: UNT Libraries Government Documents Department
open access

A global fitting code for multichordal neutral beam spectroscopic data

Description: Knowledge of the heat deposition profile is crucial to all transport analysis of beam heated discharges. The heat deposition profile can be inferred from the fast ion birth profile which, in turn, is directly related to the loss of neutral atoms from the beam. This loss can be measured spectroscopically be the decrease in amplitude of spectral emissions from the beam as it penetrates the plasma. The spectra are complicated by the motional Stark effect which produces a manifold of nine bright pe… more
Date: May 1, 1992
Creator: Seraydarian, R.P.; Burrell, K.H. & Groebner, R.J.
Partner: UNT Libraries Government Documents Department
open access

The revised International Commission on Radiological Protection (ICRP) dosimetric model for the human respiratory tract

Description: A task group has revised the dosimetric model of the respiratory tract used to calculate annual limits on intake of radionuclides. The revised model can be used to project respiratory tract doses for workers and members of the public from airborne radionuclides and to assess past exposures. Doses calculated for specific extrathoracic and thoracic tissues can be adjusted to account for differences in radiosensitivity and summed to yield two values of dose for the respiratory tract that are appli… more
Date: May 1, 1992
Creator: Bair, W.J.
Partner: UNT Libraries Government Documents Department
open access

Gene conversion in yeast as a function of linear energy transfer (LET) for low-LET radiation

Description: The relative biological effectiveness (RBE) for low-LET radiation is known to depend on such factors as LET and dose rate. Microdosimetric calculations indicate that the biological target size could also be an important parameter, and calculations predict that the RBE for effects produced by hits in target sizes below about 100 nm should be unity for all low LET radiation. We have measured that RBE for gene conversion in yeast (a small target) for five different low LET photon sources, and the … more
Date: May 1, 1992
Creator: Unrau, P.; Morrison, D.P. (Pacific Northwest Lab., Richland, WA (United States)) & Johnson, J.R. (Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.)
Partner: UNT Libraries Government Documents Department
open access

Working Group summary reports from the Advanced Photon Source reliability workshop

Description: A workshop was held at APS to address reliability goals for accelerator systems. Seventy-one individuals participated in the workshop, including 30 from other institutions. The goals of the workshop were to: (1) Give attendees an introduction to the basic concepts of reliability analysis. (2) Exchange information on operating experience at existing accelerator facilities and strategies for achieving reliability at facilities under design or in construction. (3) Discuss reliability goals for APS… more
Date: May 1, 1992
Partner: UNT Libraries Government Documents Department
open access

Perspective on photovoltaic amorphous silicon

Description: Amorphous silicon is a thin film option that has the potential for a cost-effective product for large-scale utility photovoltaics application. The initial efficiencies for single-junction and multijunction amorphous silicon cells and modules have increased significantly over the past 10 years. The emphasis of research and development has changed to stabilized efficiency, especially that of multijunction modules. NREL has measured 6.3%--7.2% stabilized amorphous silicon module efficiencies for U… more
Date: May 1, 1992
Creator: Luft, W.; Stafford, B. & von Roedern, B.
Partner: UNT Libraries Government Documents Department
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