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Proton Beam Current Measurement in the Low K.E.V. Range

Description: Secondary charge effects from a 10 kilovolt proton beam and their effect upon beam current measurement are investigated. A collector is designed for beam current metering of a 60 kilovolt proton beam by means of charge measurement and energy measurement.
Date: June 5, 1951
Creator: Fairbrother, Forrest, Jr.
open access

Synthesis and characterization of metal--metal bonded dimers of tantalum and tungsten

Description: A search for innovative synthetic routes to new metal-metal bonded metal-halide clusters resulted in isolation of two completely independent dimeric species. The syntheses and characterizations of Ta/sub 2/X/sub 6/(SC/sub 4/H/sub 8/)/sub 3/ (X = Cl, Br) and ((n-C/sub 3/H/sub 7/)/sub 4/N)/sub 2/(W/sub 2/Br/sub 9/) followed entirely different experimental routes, yet occasionally similar properties linked the two projects. (auth)
Date: December 1, 1975
Creator: Templeton, J. L.
open access

Studies of design parameters in the fabrication of Nb--Al--Ge superconductors by the powder metallurgy infiltration method

Description: Experimental studies have been carried out in which the A15 phase of the Nb-Al-Ge system has been synthesized in the form of thin filaments contained in form rolled wires. A powder metallurgy approach has been used to achieve controlled porosity in compacts of sintered niobium powder. Infiltration with an aluminum-germanium eutectic alloy followed by mechanical deformation has produced small interconnected filaments embedded in the Nb matrix. Diffusion heat treatment for a short time transforms… more
Date: December 1, 1976
Creator: Granda, Jose J.
open access

Investigations in silicate glasses. I. Radiation damage. II. Optical nonlinearity. [Gamma rays and electrons]

Description: The investigation of two poorly understood but technologically important physical properties of silicate glasses and related materials is described. The use of Electron Paramagnetic Resonance to investigate the nature of radiation-induced damage in glasses exposed to a variety of high-energy radiation sources is discussed first. Second, the measurement of the nonlinear index of refraction coefficient in a variety of optical materials related to the design of high-power laser systems is describe… more
Date: November 15, 1976
Creator: Moran, Michael James
open access

Telluric and D. C. resistivity techniques applied to the geophysical investigation of basin and range geothermal systems. Part III. The analysis of data from Grass Valley, Nevada

Description: A detailed interpretation is presented of E-field ratio telluric, bipole-dipole resistivity mapping, and dipole-dipole resistivity data obtained in the course of geophysical exploration of the Leach Hot Springs area of Grass Valley, Nevada. Several areas are singled out as being worthy of further investigation of their geothermal potential. Comparison of the three electrical exploration techniques indicates that: the bipole-dipole resistivity mapping method is the least useful; the dipole-dipol… more
Date: June 1, 1977
Creator: Beyer, J. H.
open access

Characterization of sialon-type materials

Description: Four sialon-type materials using volcanic ash as a raw material were characterized and some of their properties were determined. The M3 and M4 materials were identified as ..beta../sup 1/--Si/sub 3/N/sub 4/ sialons; their principal constituent is silicon. The M2 material was identified as a 15R-A1N polytype sialon whose principal constituent is aluminum. The M1 material is a mixture of the two types. An overview of results showing the general structural formulae and the relative order of the ma… more
Date: June 1, 1977
Creator: Spencer, P. N.
open access

A small low energy cyclotron for radioisotope measurements

Description: Direct detection of {sup 14}C by accelerator mass spectrometry has proved to be a much more sensitive method for radiocarbon dating than the decay counting method invented earlier by Libby. A small cyclotron (the cyclotrino'') was proposed for direct detection of radiocarbon in 1980. This combined the suppression of background through the use of negative ions, which had been used effectively in tandem accelerators, with the high intrinsic mass resolution of a cyclotron. Development of a small e… more
Date: November 1, 1989
Creator: Bertsche, Kirk Joseph
open access

Nucleation and dynamics of vortices in type-II superconductors

Description: The one- and two-dimensional Ginzburg-Landau equations are numerically integrated in a slab geometry, which is appropriate for comparison to experimental work done on films. When two-dimensional variations become energetically favorable, a vortex is found to nucleate and move to the center of the film with the Gibbs free energy decreasing during the process. An important process by which the energy is lowered during this nucleation procedure is found to be the savings in condensation energy ari… more
Date: March 1, 1977
Creator: Balley, R. E.
open access

Studies of fundamental properties of rutherfordium (Element 104) using organic complexing agents

Description: Chemical properties of rutherfordium (Rf) have been investigated with the organic ligands triisooctylamine (TIOA), tributylphosphate (TBP), and thenoyltrifluoroacetone (TTA). The TIOA studies showed that Rf behaves differently than Th and Eu and most similarly to Zr, only Zr and Rf extract from 12 M HCI. This result is further evidence that Rf is a Group 4 element. Studies with TBP showed that Rf chemical behavior differed from the other Group 4 elements. The extraction by TBP at different chlo… more
Date: April 1, 1992
Creator: Czerwinski, K. R.
open access

Polarized electronic spectra for the crystals of three compounds, potassium tetrabromoplatinate(II) dihydrate, tetraethylammonium hexabromodiplatinate(II), and tetra-. mu. -glycine-dimolybdenum (II) sulfate tetrahydrate

Description: The polarized absorption spectra for K/sub 2/PtBr/sub 4/ . 2H/sub 2/O, (N(C/sub 2/H/sub 5/)/sub 4/)/sub 2/PtBr/sub 6/, and Mo/sub 2/(O/sub 2/CCH/sub 2/NH/sub 3/)/sub 4/(SO/sub 4/)/sub 2/ . 4H/sub 2/O have been recorded at 300 and 15/sup 0/K. In K/sub 2/PtBr/sub 4/ . 2H/sub 2/O the bands at 24,000 and 27,000 cm/sup -1/ in both a- and b-polarizations appear to be vibronically induced. The energy spacing of the vibrational structure was noted to be somewhat higher at 180 cm/sup -1/ than for the an… more
Date: June 1, 1977
Creator: Peters, T. J.
open access

Separated-pair independent particle model and the generalized Brillouin theorem: ab initio calculations on the dissociation of polyatomic molecules

Description: A method is developed to optimize the separated-pair independent particle (SPIP) wave function; it is a special case of the separated-pair theory obtained by using two-term natural expansions of the geminals. The orbitals are optimized by a theory based on the generalized Brillouin theorem and iterative configuration interaction (CI) calculations in the space of the SPIP function and its single excitations. The geminal expansion coefficients are optimized by serial 2 x 2 CI calculations. Formul… more
Date: January 1, 1976
Creator: Sundberg, K. R.
open access

Effects of hydrogen on the single crystalline elastic constants of niobium

Description: A special hydriding system was designed and constructed to satisfy conditions for hydriding niobium. This system controlled the temperature and hydrogen atmosphere surrounding the niobium while ultrasonic measurements were recorded. Ultrasonic wave velocities were determined by measurement of the times for ultrasonic pulses to transit and then echo through known dimensions of test specimens. The method which was employed is commonly known as the pulse-echo-overlap method. This study confirmed t… more
Date: June 1, 1977
Creator: Schlader, D. M.
open access

Development of large high current density superconducting solenoid magnets for use in high energy physics experiments.

Description: The development of a unique type of large superconducting solenoid magnet, characterized by very high current density windings and a two-phase helium tubular cooling system is described. The development of the magnet's conceptual design and the construction of two test solenoids are described. The successful test of the superconducting coil and its tubular cooling refrigeration system is presented. The safety, environmental and economic impacts of the test program on future developments in high… more
Date: May 1, 1977
Creator: Green, M. A.
open access

Crystal and molecular structure of organophosphorus insecticides

Description: The crystal and molecular structures of the following organophosphorus (OP) insecticides have been determined by three-dimensional X-ray analysis: ronnel (0,0-dimethyl 0-2,4,5 trichlorophenyl phosphorothioate), ronnel oxon (0,0-dimethyl 0-2,4,5 trichlorophenyl phosphate), bomophos (0-(4-bromo-2,5-dichlorophenyl) 0,0-dimethyl phosphorothioate), Ruelene (0-(4-tert-Butyl-2-chlorophenyl)-0-methyl-N-methyl phosphoroamidate), fospirate (0,0-dimethyl 0-3,5,6-trichloro-2-pyridyl phosphate) and chlorpyr… more
Date: October 1, 1977
Creator: Baughman, R. G.
open access

Relationship of structure to effectiveness of some organophosphorus insecticides and the crystal and molecular structures of tris(bicarbonato) tetraaquoholmium (III) dihydrate and tris(ethylenediamine-cobalt (III) tetrakis (isothiocyanato cobaltate(II) nitrate

Description: Results are reported from an investigation of correlations between molecular structural parameters of selected organophosphorus insecticides and their corresponding toxic effectiveness. The crystal and molecular structures of azinphos-methyl, emidithion, and tetrachlorvinphos were determined via three-dimensional x-ray analysis. Acetylcholinesterase (AChE) in nerve cells was identified as the target for organophosphorus insecticides.
Date: June 1, 1977
Creator: Rohrbaugh, W. J.
open access

Electron Transfer at Sensitized Semiconductor Electrodes

Description: Electron transfer from the excited state of sensitizing dyes to the conduction band of semiconductors has been studied through photoelectrochemical techniques. Two systems were analyzed in detail: rhodamine B on ZnO and rose bengal on TiO/sub 2/. Prior to electrochemical experimentation, the adsorption characteristics of these dyes were investigated using ZnO, ZnS, and TiO/sub 2/ single crystals as substrates. Absorbance measurements of the adsorbed dye were taken as a function of the solution … more
Date: March 1977
Creator: Spitler, Mark Thomas
open access

Interrelationships between thermal history and mechanical properties of a secondary hardening steel. [Vasco MA steel]

Description: Commercial secondary hardening steel, VASCO MA, has been subjected to modified heat treatments to introduce mixed microstructures of martensite and lower bainite. Dilatometry, tensile testing, hardness measurements and slow-bend testing have been carried out and the mechanical properties obtained have been correlated to microstructure using scanning electron microscopy and metallography. Duplex microstructures containing small amounts of lower bainite are found to show an increased toughness (a… more
Date: December 1, 1976
Creator: Kar, N. J.
open access

Space-Charge Electrostatic Precipitation

Description: An improved electrostatic precipitator called a space charge precipitator was tested and studied. A space charge precipitator differs from a conventional model in that the fields necessary to move the particles from the gas to the collecting surfaces are provided by a cloud of charged innocuous drops, such as glycerine or water, rather than by a charged electrode system. The flow conditions, electrical equipment, and physical dimensions of the test precipitator are typical of industrial applica… more
Date: May 1, 1977
Creator: Middleton, Charles Eugene
open access

Two-state and two-state plus continuum problems associated with the interaction of intense laser pulses with atoms

Description: Two mathematical methods are utilized (one a form of adiabatic approximation, and the other closely related to the Zener method from collision theory) in order to calculate the probability of three-photon ionization when strong counter propagating pulses are tuned very near a two-photon resonant state. In this case the inverted populations predicted by Grischkowsky and Loy for smooth laser pulses lead to larger ionization probabilities than would be obtained for a square pulse of equal peak pow… more
Date: February 1, 1977
Creator: Choi, C. W. & Payne, M. G.
open access

Theoretical studies of non-Newtonian and Newtonian fluid flow through porous media

Description: A comprehensive theoretical study has been carried out on the flow behavior of both single and multiple phase non-Newtonian fluids in porous media. This work is divided into three parts: development of numerical and analytical solutions; theoretical studies of transient flow of non-Newtonian fluids in porous media; and applications of well test analysis and displacement efficiency evaluation to field problems. A fully implicit, integral finite difference model has been developed for simulation … more
Date: February 1, 1990
Creator: Wu, Yu-Shu.
open access

Two-proton pickup studies with the (6Li,8B) reaction

Description: The (/sup 6/Li,/sup 8/B) reaction has been investigated on targets of /sup 26/Mg, /sup 24/Mg, /sup 16/O, /sup 13/C, /sup 12/C, /sup 11/B, /sup 10/B, and /sup 9/Be at a bombarding energy of 80.0 MeV, and on targets of /sup 16/O, /sup 12/C, /sup 9/Be, /sup 7/Li, and /sup 6/Li at a bombarding energy of 93.3 MeV. Only levels consistent with direct, single-step two-proton pickup reaction mechanisms were observed to be strongly populated. On T/sub z/ = 0 targets, the spectroscopic selectivity of this… more
Date: December 3, 1976
Creator: Weisenmiller, Robert Benjamin
open access

Chemical shift anisotropies of /sup 1/H in H/sub 2/O(s), H/sub 2/S(s), and C/sub 6/H/sub 6/(s)

Description: The proton NMR in powdered samples of H/sub 2/O(s), H/sub 2/S(s), and C/sub 6/H/sub 6/(s) have been studied by multiple pulse line narrowing techniques. The resultant spectra provide nuclear magnetic shielding tensors that are (at least approximately) axially symmetric. The anisotropy is 34.2 +- 1.0 ppM for ice, 11.1 +- 1.0 ppM for the highest-temperature phase of solid hydrogen sulfide, and -5.3 +- 0.3 for benzene. Comparisons are made with previous experimental and theoretical work.
Date: October 1, 1977
Creator: Ryan, L. M.
open access

Reaction of Tris(cyclopentadienyl)uranium compounds with amines, azides, and related ligands

Description: The trivalent uranium compound, (MeC{sub 5}H{sub 4}){sub 3}U(thf), serves as a one- or two-electron reducing agent towards azides, RN{sub 3}. These reactions produce either the uranium(IV) azide, (MeC{sub 5}H{sub 4}){sub 3}UN{sub 3}, or uranium(V) imides, (MeC{sub 5}H{sub 4}){sub 3}UNR. The role of steric and electronic effects upon this reaction has been investigated using several series of azides. For Me{sub 3}XN{sub 3}, the imides are produced when X = C or Si, both products are formed when … more
Date: December 1, 1989
Creator: Rosen, Robert Keith
open access

High-Pressure Catalytic Microreactor for Hydroprocessing of Coal-Derived Liquids. [10 References]

Description: A high-pressure liquid-phase microreactor was developed to determine the kinetics and reaction networks of catalytic hydrodesulfurization and hydrodenitrogenation of polynuclear aromatic compounds found in coal-derived liquids. This reactor permits the use of small quantities of reactants and catalyst. This reactor design is expected to be useful generally and is not limited to hydroprocessing. The microreactor was designed to operate entirely in the liquid phase. The hydrogen required for the … more
Date: June 1976
Creator: Eliezer, Kenneth Frank
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