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International Conference on Fundamental Aspects of Weak Interactions: Held at Brookhavan National Laboratory, September 9-11, 1963

Description: Report issued by the Brookhaven National Laboratory discussing papers presented at the International Conference on Fundamental Aspects of Weak Interactions. Each paper that was presented at the conference is included. This report includes tables, illustrations, and photographs.
Date: April 1964
Creator: Brookhaven National Laboratory
Partner: UNT Libraries Government Documents Department

Detection of plutonium with the microwave plasma continuous emissions monitor

Description: The first successful detection of plutonium with a continuous microwave plasma emissions monitor has been demonstrated. Seven plutonium emission peaks in the 362 - 366 nm and 449 - 454 nm ranges were clearly observed. The strongest peak was at 453.62 nm. This peak and five of the other plutonium peaks were easily distinguishable from possible interference from iron emission peaks with a spectrometer resolution of 0.1 nm. 2 refs., 3 figs.
Date: September 1, 1995
Creator: Rhee, D.Y.; Woskov, P.P.; Gervais, K. & Surma, J.E.
Partner: UNT Libraries Government Documents Department

A Planar Quantum Transistor Based on 2D-2D Tunneling in Double Quantum Well Heterostructures

Description: We report on our work on the double electron layer tunneling transistor (DELTT), based on the gate-control of two-dimensional -- two-dimensional (2D-2D) tunneling in a double quantum well heterostructure. While previous quantum transistors have typically required tiny laterally-defined features, by contrast the DELTT is entirely planar and can be reliably fabricated in large numbers. We use a novel epoxy-bond-and-stop-etch (EBASE) flip-chip process, whereby submicron gating on opposite sides of semiconductor epitaxial layers as thin as 0.24 microns can be achieved. Because both electron layers in the DELTT are 2D, the resonant tunneling features are unusually sharp, and can be easily modulated with one or more surface gates. We demonstrate DELTTs with peak-to-valley ratios in the source-drain I-V curve of order 20:1 below 1 K. Both the height and position of the resonant current peak can be controlled by gate voltage over a wide range. DELTTs with larger subband energy offsets ({approximately} 21 meV) exhibit characteristics that are nearly as good at 77 K, in good agreement with our theoretical calculations. Using these devices, we also demonstrate bistable memories operating at 77 K. Finally, we briefly discuss the prospects for room temperature operation, increases in gain, and high-speed.
Date: December 14, 1998
Creator: Baca, W.E.; Blount, M.A.; Hafich, M.J.; Lyo, S.K.; Moon, J.S.; Reno, J.L. et al.
Partner: UNT Libraries Government Documents Department

Synthesis of Ozone at Atmospheric Pressure by a Quenched Induction-Coupled Plasma Torch

Description: The technical feasibility of using an induction-coupled plasma (ICP) torch to synthesize ozone at atmospheric pressure is explored. Ozone concentrations up to ~250 ppm were produced using a thermal plasma reactor system based on an ICP torch operating at 2.5 MHz and ~11 kVA with an argon/oxygen mixture as the plasma-forming gas. A gaseous oxygen quench formed ozone by rapid mixing of molecular oxygen with atomic oxygen produced by the torch. The ozone concentration in the reaction chamber was measured by Fourier Transform infrared (FTIR) spectroscopy over a wide range of experimental configurations. The geometry of the quench gas flow, the quench flow velocity, and the quench flow rate played important roles in determining the ozone concentration. The ozone concentration was sensitive to the torch RF power, but was insensitive to the torch gas flow rates. These observations are interpreted within the framework of a simple model of ozone synthesis.
Date: January 1, 1998
Creator: Blutke, A.; Stratton, B.C.; Mikkelsen, D.R.; Vavruska, J. & Knight, R.
Partner: UNT Libraries Government Documents Department

Experimental Test of the Sweet-Parker Model of Magnetic Reconnection

Description: We report a quantitative experimental test of the Sweet-Parker model of magnetic reconnection in a controlled laboratory plasma. It is found that the observed reconnection rate cannot be explained by the Sweet-Parker model unless the model is generalized to incorporate compressibility, downstream pressure, and the effective resistivity. The latter is significantly enhanced over its classical values in the collisionless limit.
Date: September 1, 1997
Creator: Hsu, Scott; Ji, Hantao; Kulsrud, Russell & Yamada, Masaaki
Partner: UNT Libraries Government Documents Department

Survey and analysis of line-frequency interference in the CEBAF accelerator

Description: Feedthrough of interference from the AC power line into accelerator components is a problem which in pulsed accelerators can be reduced by operation synchronous with the AC line. This means of avoiding line-frequency effects is ineffective for continuous wave machines such as the CEBAF accelerator. We have measured line-frequency perturbations at CEBAF both in beam position and energy by using the beam position monitor system as a multiple-channel sampling oscilloscope. Comparing these data against the measured static optics (taken synchronously with the AC line) we have been able to identify point sources of interference, and resolve line-synchronous variations in the beam energy at a level near 0.001%. 3 refs., 2 figs., 1 tab.
Date: December 31, 1995
Creator: Tiefenback, M.G. & Li, Rui
Partner: UNT Libraries Government Documents Department

Electrodeposition research progress report, March 1--31, 1948

Description: Plating of Postum out of Nitric Acid and Hydrofluoric Acid Solutions -- W. Abel and W. Raiff. Postum was plated out of 1.5 normal nitric acid and 1.0 normal hydrofluoric acid under similar conditions. The hydrofluoric acid plate was better appearing, and had a much higher curie density. However, neutron counts in these runs were quite similar. Neutron Counts -- W. Abel and W. Raiff. A study of the change of neutron counts over a period of time was started. Conversion of Active Hydrofluoric Acid Solutions to Hydrochloric Acid Solutions -- W. Raiff. A 99.99+ per cent conversion was effected. Conversion of Production Solutions to 1.0 Normal Hydrofluoric Add Solutions -- R. Bell. Good conversion has been achieved; however, further work needs to be done on complete change of postum from the production solution to 1.0 normal hydrofluoric acid solutions.
Date: December 31, 1948
Creator: Orban, E.
Partner: UNT Libraries Government Documents Department

Location and correction of 60 hz in the CEBAF injector

Description: CEBAF produces a continuous electron beam with an emittance of 2-3 nm-rad. Transverse low frequency magnetic oscillations act to dilute this emittance. These fields are typically associated with AC line conductors. The CEBAF injector is approximately 40 m long. To locate the source(s) of the beam motion, measured offsets were back propagated along the beamline using the DIMAD model. Field measurements were then made at the calculated field source positions and correlated with the measured effects. Corrections and final beam measurements were made to verify the corrections. 2 refs., 4 tabs.
Date: August 1, 1996
Creator: Legg, R.; Douglas, D.; Krafft, G.A. & Saulter, Q.
Partner: UNT Libraries Government Documents Department

Magnetic confinement experiment -- 1: Tokamaks

Description: This report reviews presentations made at the 15th IAEA Conference on Plasma Physics and Controlled Nuclear Fusion on experimental tokamak physics, particularly on advances in core plasma physics, divertor and edge physics, heating and current drive, and tokamak concept optimization.
Date: December 31, 1994
Creator: Goldston, R.J.
Partner: UNT Libraries Government Documents Department

Monsanto Chemical Company, Unit 3 progress report, January 16--31, 1948

Description: Solubilities -- Orban: The solubility of postum in various concentrations of nitric acid was determined at 25.4{degrees}C. Hydrofluoric and Trifluoroacetic Acids -- Abel and Raiff: Details of this work will be reported in the next Progress Report. Conversion of Nitric Acid Solutions to Hydrofluoric Acid Solutions -- Bell: Conversion of production solutions to hydrofluoric acid solutions was tried by precipitation with ammonium oxalate, aluminum hydroxide, ammonium hydroxide, and sodium carbonate. Silver and Teflon discs were used.
Date: December 31, 1948
Partner: UNT Libraries Government Documents Department

Electrical resistivity measurements of a dense aluminum plasma

Description: In this paper the authors report results of experiments to measure the electrical resistivity for a dense strongly coupled aluminum plasma. These plasmas cover the density and temperature range from near solid density and room temperature to .03x solid and 40 eV. These conditions give values of {Lambda} = 5--6. The results indicate the resistivity is higher in this regime than most theories. Only the results of some density functional calculations give results consistent with the data.
Date: September 1, 1995
Creator: Benage, J.F. Jr.; Shanahan, W.R. & Murillo, M.S.
Partner: UNT Libraries Government Documents Department

Coal log pipeline research at University of Missouri. 3rd quarterly report for 1995, July 1, 1995--September 30, 1995

Description: During this quarter (1/1/95-9/30/95), major progress has been made in the following areas of coal log pipeline research, development and technology transfer: (1) Conceptual design of a test machine based on hydraulic presses to mass-produce 5.4-inch-diameter coal logs for testing in a 6-inch-diameter pipeline has been completed. (2) Conceptual design of a rotary-press machine to produce 1.9-inch-diameter coal logs for testing in a 2-inch-diameter pipeline has also been completed. (3) It has been confirmed through experiments that molds with round-edge exit can make logs as good as those made with tapered exit. (4) Conducted a study to determine the effect of surface condition of mold and lubricants on the quality of coal logs. (5) Completed an evaluation of the effect of fiber (wood pulp) on coal log quality. (6) Prepared an apparatus for testing fast compaction of coal logs -- 2 second per log. (7) Compacted coal logs in a 5.3-inch-diameter mold. (8) Completed a preliminary study to assess vacuum and steam heating systems to enhance coal log production and quality. (9) Changed the small-scale-CLP-demo loop from a once-through system to a recirculating system. (10) Completed revision of CLP economic model and revised the 1993 report.
Date: December 31, 1995
Creator: Liu, H.
Partner: UNT Libraries Government Documents Department

Beam loading effects in the APS booster

Description: Beam loading of the radio-frequency (rf) accelerating cavities is an important consideration in the design and operation of high-current circular particle accelerators and storage rings. The steady-state and transient perturbations of the rf cavity system by the circulating beam can be harmful to the beam and limit the accelerator performance. Transient beam loading effects have been observed soon after injection of the beam into the booster synchrotron of the Advanced Photon Source (APS). Data are presented quantifying the responses of both the beam and the rf cavities to beam loading under various conditions. A preliminary discussion addresses the compensation of these beam loading effects. 3 refs., 3 figs., 1 tab.
Date: June 1, 1996
Creator: Harkay, K.; Lumpkin, A.; Milton, S.; Nassiri, A.; Song, J. & Yang, B.
Partner: UNT Libraries Government Documents Department

The role of ALCHEMI in understanding the properties of ordered intermetallic alloys

Description: After one and one-half decades of development, ALCHEMI is approaching the status of an established analytical technique. Many of the problems that have plagued ALCHEMI, especially for the analysis of ordered intermetallic alloys, are now well understood, and accurate site-distributions can be extracted from a variety of intermetallic alloys. This paper begins with an overview of the factors that can lead to large systematic errors or gross misinterpretations of ALCHEMI data, with illustrations from a variety of ordered intermetallic alloys. The paper concludes with a discussion of ALCHEMI in the broader context of understanding the properties of ordered intermetallic alloys. The results of systematic studies are used to illustrate the role of ALCHEMI in determining the competing effects of thermodynamic and kinetic factors during alloy processing and the correlation of alloy properties with the atomic site distributions on which the properties ultimately depend.
Date: November 1, 1998
Creator: Anderson, I.M.
Partner: UNT Libraries Government Documents Department

Mechanical behavior of robocast alumina

Description: Direct fabrication of alumina parts by robocasting was completed. This method is based on three-dimensional deposition of binderless aqueous alumina slurries. Parts were made with different deposition paths and mechanical testing performed to determine the effects of bead alignment. Properties were also compared to alumina processed more traditionally.
Date: December 1, 1998
Creator: Denham, H.B.; Cesarano, J. III; King, B.H. & Calvert, P.
Partner: UNT Libraries Government Documents Department

Microstructure of compositionally modulated InAlAs

Description: The authors have observed spontaneous, lateral composition modulation in tensile InAlAs alloy films grown as short-period superlattices on InP (001). They have analyzed these films using transmission electron microscopy, x-ray reciprocal space mapping, and polarized photoluminescence spectroscopy. They find the growth front is nonplanar, exhibiting {approximately} 2 nm deep cusps aligned with the In-rich regions of the compositionally modulated films. In addition to the measured 15 nm wavelength modulation in the [110] direction, a modulation of 30 nm wavelength is seen in the orthogonal [1{bar 1}0] direction. The photoluminescence from the modulated layer is strongly polarized and red shifted by 0.22 eV.
Date: December 31, 1996
Creator: Twesten, R.D.; Millunchick, J.M.; Lee, S.R.; Follstaedt, D.M.; Jones, E.D.; Ahrenkiel, S.P. et al.
Partner: UNT Libraries Government Documents Department

Solenoid fringe field compensation for the Cluster Klystron

Description: Optimization of the solenoid pancake currents so as to have a uniform axial magnetic field over an extended volume, is very important for the successful operation of the Cluster Klystron. By boosting the first and the last pancake currents by 35%, a uniform field Br/Bz {le} 0.1% at radius R {le} 2 cm can be extended from {+-} 7 cm to {+-} 16 cm. The result confirms simulations and the requirements for a 3-beam Cluster Klystron Experiment are achieved.
Date: April 1, 1996
Creator: Wang, H.; Fernow, R.C.; Kirk, H.G.; Palmer, R.B. & Zhao, Y.
Partner: UNT Libraries Government Documents Department

In situ global method for measurement of oxygen demand and mass transfer

Description: Two aerobic microorganisms, Saccharomycopsis lipolytica and Brevibacterium lactofermentum, have been used in a study of mass transfer and oxygen uptake from a global perspective using a closed gas system. Oxygen concentrations in the gas and liquid were followed using oxygen electrodes, and the results allowed for easy calculation of in situ oxygen transport. The cell yields on oxygen for S. lipolytica and B. lactofermentum were 1.01 and 1.53 g/g respectively. The mass transfer coefficient was estimated as 10 h{sup {minus}1} at 500 rpm for both fermentations. The advantages with this method are noticeable since the use of model systems may be avoided, and the in situ measurements of oxygen demand assure reliable data for scale-up.
Date: May 1, 1997
Creator: Klasson, K.T.; Lundbaeck, K.M.O.; Clausen, E.C. & Gaddy, J.L.
Partner: UNT Libraries Government Documents Department

The effect of neutron irradiation on silicon carbide fibers

Description: Nine types of SiC fiber have been exposed to neutron radiation in the Advanced Test Reactor at 250 C for various lengths of time ranging from 83 to 128 days. The effects of these exposures have been initially determined using scanning electron microscopy. The fibers tested were Nicalon{trademark} CG, Tyranno, Hi-Nicalon{trademark}, Dow Corning SiC, Carborundum SiC, Textron SCS-6, polymethysilane (PMS) derived SiC from the University of Michigan, and two types of MER SiC fiber. This covers a range of fibers from widely used commercial fibers to developmental fibers. Consistent with previous radiation experiments, Nicalon fiber was severely degraded by the neutron irradiation. Similarly, Tyranno suffered severe degradation. The more advanced fibers which approach the composition and properties of SiC performed well under irradiation. Of these, the Carborundum SiC fiber appeared to perform the best. The Hi-Nicalon and Dow Corning Fibers exhibited good general stability, but also appear to have some surface roughening. The MER fibers and the Textron SCS-6 fibers both had carbon cores which adversely influenced the overall stability of the fibers.
Date: January 1, 1997
Creator: Newsome, G.A.
Partner: UNT Libraries Government Documents Department

A Hollow Cathode Magnetron (HCM)

Description: A new type of plasma sputtering device, named the hollow cathode magnetron (HCM), has been developed by surrounding a planar magnetron cathode with a hollow cathode structure (HCS). Operating characteristics of HCMs, current-voltage ( I-V ) curves for fixed discharge pressure and voltage-pressure ( V-p ) curves for fixed cathode current, are measured. Such characteristics are compared with their planar magnetron counterparts. New operation regimes, such as substantially lower pressures (0.3 mTorr), were discovered for HCMs. Cathode erosion profiles show marked improvement over planar magnetron in terms of material utilization. The use of HCMs for thin film deposition are discussed.
Date: April 1, 1998
Creator: Cohen, S.A. & Wang, Z.
Partner: UNT Libraries Government Documents Department