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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

Operating experience with the ALS linac

Description: The linac injector for the Advanced Light Source (ALS) at LBL was recently put into operation. Energy is 50 MeV, frequency 3 GHz. The electron gun delivers up to 6nC in a 3.0-ns bunch at 120 kV. A train of bunches is injected into a 1-Hz booster and accelerated to 1.5 GHz for storage ring injection. A magnetic analysis system is used for optimizing the linac. Measured beam properties from the gun and after acceleration in the linac are described. 9 refs., 3 figs.
Date: May 1, 1991
Creator: Selph, F. & Massoletti, D.
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
open access

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

Laser diagnostics of H sup minus formation in a magnetic multicusp ion source

Description: The populations of ground electronic state atomic hydrogen and ground electronic state, vibrationally-rotationally excited hydrogen molecules in a negative hydrogen ion source discharge have been measured using vacuum ultraviolet (VUV) laser absorption spectroscopy. Vibrational states up to v=8 and rotational levels as high as J=15 have been measured. The measurements have been made under a range of discharge conditions. The complete vibrational population distribution for v=1-8, J=1 has been o… more
Date: May 1, 1991
Creator: Young, A. T.; Chen, P.; Kunkel, W. B.; Leung, K. N.; Li, C. Y. & Stutzin, G. C.
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

Effect of Au on the reliability of fine pitch surface mount solder joints

Description: The effect of Au on the reliability of 0.65 mm pitch surface mount solder joints between plastic quad flat packs and Cu-Ni-Au FR-4 printed circuit boards was investigated. Cu-Ni-Au is a desirable printed circuit board finish for multi-chip modules or printed circuit boards that would otherwise require a selective Au finish, for example for edge connectors or wire bondable parts. However, Au is known to embrittle solder when it is present in sufficiently high concentrations, creating a concern t… more
Date: May 1, 1991
Creator: Glazer, J. (Hewlett-Packard Co., Palo Alto, CA (United States)); Kramer, P. & Morris, J.W. Jr. (Lawrence Berkeley Lab., CA (United States))
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

Numerical simulations of turbulent flow fields caused by spraying of water on large releases of hydrogen fluoride

Description: The effectiveness of water sprays in absorbing HF releases was recently demonstrated in extended laboratory and field tests. In this paper, computer simulations are presented of the Hawk, Nevada Test Site, series of field tests. The model used, HFSPRAY, is a Eulerean/Lagrangian model which simulates the momentum, mass and energy interactions between a water spray and a turbulent plume of HF in air; the model can predict the flow velocities, temperature, water vapor, and HF concentration fields … more
Date: May 1, 1991
Creator: Fthenakis, V.M. (Brookhaven National Lab., Upton, NY (United States)) & Schatz, K.W. (Mobil Research and Development Corp., Princeton, NJ (United States))
Partner: UNT Libraries Government Documents Department
open access

D. phi. vertex drift chamber construction and test results

Description: A jet-cell based vertex chamber has been built for the D{O} experiment at Fermilab and operated in a test beam there. Low drift velocity and diffusion properties were achieved using CO{sub 2}(95%)-ethane(5%) at atmospheric pressure. The drift velocity is found to be consistent with (9.74+8.68( E -1.25)) {mu}m/nsec where E is the electric field strength in (kV/cm < E z 1.6 kV/cm.) An intrinsic spatial resolution of 60 {mu}m or better for drift distances greater than 2 mm is measured. The track p… more
Date: May 1, 1991
Creator: Clark, A.R.; Goozen, F.; Grudberg, P.; Klopfenstein, C.; Kerth, L.T.; Loken, S.C. et al.
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

Magnetic data analysis for the ALS lattice magents

Description: The Advanced Light Source (ALS), now under construction at Lawrence Berkeley Laboratory, is a third-generation synchrotron radiation source designed to produce extremely bright photon beams in the UV and soft X-ray regions. The lattice magnets to be installed in the two rings, a 1--1.9 GeV storage ring, and a 1.5 GeV booster synchrotron, have been magnetically measured to ascertain their excitation curves and field uniformity. In this paper the analysis of these data is discussed, and results f… more
Date: May 1, 1991
Creator: Keller, R.
Partner: UNT Libraries Government Documents Department
open access

Critical flow: General theory and spurious solutions

Description: It is hardly necessary to emphasize the importance that an accurate prediction of the parameters of critical flow plays in a number of industries, notably in nuclear reactor safety calculations and in metering. In spite of its importance, the literature of the subject still contains erroneous statements. Many of them result from an unjustified belief in the generality of certain conclusions drawn in the elementary study of one-dimensional isentropic flow of a perfect gas with constant specific … more
Date: May 1, 1991
Creator: Kestin, J.
Partner: UNT Libraries Government Documents Department
open access

Pulse code modulation data compression for automated test equipment

Description: Development of automated test equipment for an advanced telemetry system requires continuous monitoring of PCM data while exercising telemetry inputs. This requirements leads to a large amount of data that needs to be stored and later analyzed. For example, a data stream of 4 Mbits/s and a test time of thirty minutes would yield 900 Mbytes of raw data. With this raw data, information needs to be stored to correlate the raw data to the test stimulus. This leads to a total of 1.8 Gb of data to be… more
Date: May 1, 1991
Creator: Navickas, T.A. & Jones, S.G.
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

Broadband diffractive lens

Description: Significant progress has been made toward solving the century-old problem of chromatic aberrations in diffractive optics. Our approach exploits modern materials and microfabrication technology and is very different from the purely diffractive strategy,'' which is commonly employed and which results in multiple diffractive elements separated by a finite distance. We have developed a Fresnel zone plate lens comprised of a serial stack of patterned minus-filters which allows broadband radiation to… more
Date: May 28, 1991
Creator: Ceglio, N. M.; Hawryluk, A. M.; London, R. A.; Seppala, L. G. (Lawrence Livermore National Lab., CA (USA)) & Gaines, D. P. (Brigham Young Univ., Provo, UT (USA))
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
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