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ANHARMONIC POTENTIAL CONSTANTS AND THEIR DEPENDENCE UPON BOND LENGTH (open access)

ANHARMONIC POTENTIAL CONSTANTS AND THEIR DEPENDENCE UPON BOND LENGTH

Empirical study of cubic and quartic vibrational force constants for diatomic molecules shows them to be approximately exponential functions of internuclear distance. A family of curves is obtained, determined by the location of the bonded atoms in rows of the periodic table. Displacements between successive curves correspond closely to those in Badger's rule for quadratic force constants (for which the parameters are redetermined to accord with all data now available). Constants for excited electronic and ionic states appear on practically the same curves as those for the ground states. Predictions based on the diatomic correlations agree with the available cubic constants for bond stretching in polyatomic molecules, regardless of the type of bonding involved. Implications of these regularities are discussed. (auth)
Date: August 1, 1961
Creator: Herschbach, D.R. & Laurie, V.W.
System: The UNT Digital Library
PROCEEDINGS OF THE FIRST LAMPF USERS' MEETING, LOS ALAMOS, NEW MEXICO, JUNE 20, 1968. (open access)

PROCEEDINGS OF THE FIRST LAMPF USERS' MEETING, LOS ALAMOS, NEW MEXICO, JUNE 20, 1968.

None
Date: January 1, 1968
Creator: Emigh, C. R. & Harper, K. H.
System: The UNT Digital Library
Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite (open access)

Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite

An equation of state previously used by the author is developed further and applied to geologic media. The equation is of the same form as the Murnaghan equation of state, but with the elastic constant terms replaced by the cohesive energy density (internal pressure), and the exponential term given as a sum of the Gruneisen parameter and the gaseous adiabatic exponent. Data for shock compression of silica, basalt, and dolomite are analyzed according to the equation.
Date: December 20, 1965
Creator: Rogers, L.A.
System: The UNT Digital Library
AN INFORMATION STORAGE AND RETRIEVAL SYSTEM FOR IRRADIATION EFFECTS IN METALS (open access)

AN INFORMATION STORAGE AND RETRIEVAL SYSTEM FOR IRRADIATION EFFECTS IN METALS

An information storage and retrieval system (PIC) was developed, utilizing the IBM 7090 computer, for handling data pertaining to the effects of neutron irradiation on metals. The input includes a reference identification, an appropriate abstract or extract summarizing the article, code identification parameters analogous to those used by the ASM-SLA Literature Classification System, and special codes identifying relevant irradiation and testing parameters. The output contains the same data plus printing out the meaning of all special codes. Presently, the information storage consists of more than two hundred references representing several thousand lines of information. The system is both general and definitive, permitting the selection of a single piece of information or of many references dealing with a general field. It is possible to select material on the basis of one or more of the following factors: material, general or specific; type of literature; general or specific property such as mechanical tests or tensile tests; conditions of irradiation including type and level of flux, integrated flux, irradiation temperature, and reactor environment; test conditions such as temperature and environment; and general variables that might be controlling such as strain rate, specimen geometry, grain size, and fabrication history. It is felt that this …
Date: August 15, 1963
Creator: Bush, S. H.
System: The UNT Digital Library
Physics Performance of the EBWE in Its Zero to 100 Mw Operation (open access)

Physics Performance of the EBWE in Its Zero to 100 Mw Operation

The distribution of fuel elements in the EBWR core is described. Spike elements with boron steel strips were provided in the core for burnup allowance. A calibration of the control rod system with Zircaloy followers was made. Void coefficient measurements were made for two different H/sub 3/BO/sub 3/ concentrations. Power runs were made, and reactivity loss vs. power characteristic was obtained. Steam remaining in the core, or carryunder,'' was indicated. Some of the spikes were removed for increasing the power to 80 Mw. Calculations were made of the reactivity loss with coolant void and of the average void vs. reactor power. (D. L.C.)
Date: June 1963
Creator: Iskenderian, H. P.
System: The UNT Digital Library
Hyperfine Structure of the Electronic Ground States of Rb$sup 85$ And Rb$sup 8$$sup 7$ (open access)

Hyperfine Structure of the Electronic Ground States of Rb$sup 85$ And Rb$sup 8$$sup 7$

None
Date: July 15, 1962
Creator: Penselin, S.; Moran, T.; Cohen, V.W. & Winkler, G.
System: The UNT Digital Library
Laboratory-Scale Demonstration of the Fused Salt Volatility Process (open access)

Laboratory-Scale Demonstration of the Fused Salt Volatility Process

The feasibility of processing enriched irradiated zirconium--uranium alloy fuel by the fused salt-fluoride volatility procedure has been demonstrated in laboratory tests with fuel having a burnup of over 10%. Uranium recoveries were greater than 99% and decontamination factors for radioactive fission products were 10/sup 6/ to 10/sup 6/. The UF/sub 6/ product contained significant quantities of nonradioactive impurities; additional work in this area is needed. (auth)
Date: August 1, 1962
Creator: Cathers, G. I.; Jolley, R. L. & Moncrief, E. C.
System: The UNT Digital Library
A PULSED EDDY CURRENT TEST SYSTEM USING REFLECTED FIELDS (open access)

A PULSED EDDY CURRENT TEST SYSTEM USING REFLECTED FIELDS

An eddy current test system is described in which the test information is detected as a series of fields reflected from the metal surface and interior. Pulsed electromagnetic fields are caused to impinge upon the test specimen. These fields are restricted to a small cross sectional area over a path in space long enough to be useful for test purposes by devices called mask-apenture assemblies. This approach provides a number of advantages over conventional eddy current methods of comparable capabilities, including superior surface resolution, a reduction in circuit complexity, and an improvement in stability and reliability. Various applications and test results are discussed. (auth)
Date: June 11, 1962
Creator: Renken, C. J.
System: The UNT Digital Library
Measurement of the K{sup 0}{sub S} - K{sup 0}{sub L} mass difference by the time dependence of strangeness (open access)

Measurement of the K{sup 0}{sub S} - K{sup 0}{sub L} mass difference by the time dependence of strangeness

The magnitude of the K{sup 0}{sub S} - K{sup 0}{sub L} mass difference has been measured by monitoring the time dependence of the strangeness of neutral K's produced in hydrogen and deuterium in the LRL 25 '' hydrogen bubble chamber. The particles originate as K-bar{sup 0} in K{sup -} change-exchange scatters at .85 to 1.15 Bev/c; the signature for an S = -1 reaction is the production of a hyperon. Seventy- seven events were found, obtaining {Delta}{omega} = 0.50 =- 0.15, measured in units of inverse K{sup 0}{sub S} lifetime. This and two other recent measurements using the same method are consistent with one another and with measurements of {Delta}{omega} by other means. A combined ''world average'' of nine reasonably consistent measurements gives {Delta}{omega} = 0.60 +- 0.06.
Date: April 1, 1966
Creator: Camerini, U.; Cline, D.; English, J. B.; Fischbein, W.; Fry, W. F.; Gaidos, J. A. et al.
System: The UNT Digital Library
Secondary Isotope Effects in Molecular Structure (open access)

Secondary Isotope Effects in Molecular Structure

A study was made to determine whether secondary iso tope effects also occur in molecular structure. Electron diffraction studies were carried out on ethane and deuteroethane. In C/sub 2/H/sub 6/ the mean C-C and C-H bond lengths found agreed very closely with values determined for other paraffin hydrocarbons, and the C--H bond showed a normal primary isotope effect (~ 0.005 A) similar to that found in methane when H is replaced by O. The output of the leastsquares analysis suggested that the mean C-- C bond length in C/sub 2/D/sub 6/ is shorter than in C/sub 2/H/sub 6/ and by about 0.004 A. Th e decrease seemed to be real for the apparent uncertainty was not much greater than 0.001 A. (M.C.G.)
Date: June 15, 1962
Creator: Bartell, L. S.
System: The UNT Digital Library
Studies on Lymphocytes. [Part] 1. Lymphopenia Produced by Prolonged Extracorporeal Irradiation of Circulating Blood (open access)

Studies on Lymphocytes. [Part] 1. Lymphopenia Produced by Prolonged Extracorporeal Irradiation of Circulating Blood

A method for extracorporeal irradiation of the circulating blood is described. Extracorporeal irradiation of the blood will produce a lymphopenia promptly which persists for weeks. Heparin in high doses in the calf produces a lymphocytosis and neutrophilic leukocytosis. (auth) Red cell sensitization by either agglutinating or incomplete antibodies was detected with an I/sup 131/ labeled rabbit antihuman globulin serum (RAG). Non-specific absorption of RAG by red cells was reduced to a minimum by the addition of 6% bovine albumin. The reactions between RAG and the sensitized erythrocytes were typical of antigen- antibody reactions and the sensitivity of the test was found to be greater than the standard Coombs test. Quantitative studies of the degree of erythrocyte sensitization by isoimmune or autoimmune antibodies were possible with this technic. (auth)
Date: August 1, 1962
Creator: Cronkite, E. P.; Jansen, C. R.; Mather, G. C.; Nielsen, N. O.; Usenik, E. A.; Adamik, E. R. et al.
System: The UNT Digital Library
New Hot Laboratory Facilities at Los Alamos (open access)

New Hot Laboratory Facilities at Los Alamos

New Hot Laboratory Facilities which support three major research programs directed by the Los Alamos Scientific Laboratory of the University of California are described. For the Nuclear Rocket Propulsion Program, a hot cell addition to the Radio Chemistry Building at Los Alamos will be completed early in 1963, and construction is expected to start soon on the hot cell addition to the Maintenance, Assembly and Disassembly Building at the Nuclear Rocket Development Station in Nevada. Integral hot laboratories are designed in the facilities for the Ultra High Temperature Reactor Experiment and the Fast Reactor Core Test at Los Alamos. (auth)
Date: January 1, 1962
Creator: Wherritt, Charles R.; Franke, Paul R.; Field, R. E. & Lyle, A. R.
System: The UNT Digital Library
A Modified Pyroelectric Sodium Fluoride Carrier Distillation Medthod For The Spectrographic Analysis Of Impurities In Plutonium (open access)

A Modified Pyroelectric Sodium Fluoride Carrier Distillation Medthod For The Spectrographic Analysis Of Impurities In Plutonium

A modification of the pyroelectric sodium fluoride carrier distillation method for analysis of impurities in plutonium metal is described. The metal is dissolved. Plutonium is precipitated and treated with nitric acid. The slurry obtained is dried and ignited. The resultant low density oxide is mixed with sodium fluoride and pressed into a pellet for arcing. Cobalt is used as the internal standard for densitometric using visual comparisons against prepared standards. The procedural modifications improve reproducibility and sensitivity of most of the elements involved. (auth)
Date: August 1, 1966
Creator: Schreiber, G. A. & Barrick, C. W.
System: The UNT Digital Library
Analysis of Vanadium in Milk Powder by Neutron Activation Analysis Using a Rapid Radiochemical Separation of 3.77-Minute Vanadium-52 (open access)

Analysis of Vanadium in Milk Powder by Neutron Activation Analysis Using a Rapid Radiochemical Separation of 3.77-Minute Vanadium-52

A procedure is described for the activation determination of V in powdered milk using 3.77-min V/sup 52/. The quantity of V in the sample is obtained by comparing the V/sup 52/ radioactivity found in the test sample with the V/sup 52/ radioactivity in a V comparator sample that is treated in the same manner as the test sample. The procedure can also be used for the determination of V in a variety of materials. (P.C.H.)
Date: November 15, 1963
Creator: Molinski, V. J.; Wahl, W. H. & Strain, W. H.
System: The UNT Digital Library
The Structures of NiZr$sub 2$, NiZr and Their Hafnium Analogs (open access)

The Structures of NiZr$sub 2$, NiZr and Their Hafnium Analogs

None
Date: March 10, 1962
Creator: Kikpatrick, M. E.; Bailey, D. M. & Smith, J. F.
System: The UNT Digital Library
Electrical and Magnetic Properties of Holmium Single Crystals (open access)

Electrical and Magnetic Properties of Holmium Single Crystals

Magnetic moment measurements are made on holmium single crystals (hcp) from 1.3 to 300 deg K in magnetic fields from 250 to 18,000 Oe, with the field applied along the c axis, the a axis, and a (1010) direction. The STA1010! direction is the direction of easy magnetization with an extrapolated effective moment per atom at saturation of 10.34 Bohr magnetons. Basal plane measurements show antiferromagnetism below the Neel temperature of 132 deg K with basal plane anisotropy occurring below 80 deg K. Below the Neel point, an anomalous type of transition to ferromagnetic behavior upon application of sufficient field is observed. Magnetization curves for the c axis are linear down to 60 deg K, while measurements below 20 deg K show an initial magnetization of approximately 1.7 Bohr magnetons followed by nearly linear magnetization curves. Electrical resistivity measurements are made from 4.2 to 300 deg K. For the a axis, the resistivity changes slope slightly at 20 deg K. A larger change in slope occurs at the Neel temperature of 132 deg K. For the c axis, the resistivity changes slope slightly at 20 deg K, reaches a peak at 120 deg K, goes through a minimum at 132 …
Date: September 15, 1962
Creator: Strandburg, D. L.; Legvold, S. & Spedding, F. H.
System: The UNT Digital Library
Superconducting Critical Field of Tantalum as a Function of Temperature and Pressure (open access)

Superconducting Critical Field of Tantalum as a Function of Temperature and Pressure

None
Date: August 15, 1961
Creator: Hinrichs, C. H. & Swenson, C. A.
System: The UNT Digital Library
Nuclear Contribution to the Heat Capacity of Terbium Metal (open access)

Nuclear Contribution to the Heat Capacity of Terbium Metal

The heat capacity of terbium metal was measured between 0.25 and 1.0 deg K. The high temperature data can be expressed as C = 28R x 10/sup -3/T/sup 2/ cal/ mole-deg. The data are compared with a Schottky formula for the heat capacity, assuming equal spacing between the nuclear hyperfine levels with an over-all spacing of beta = 0.45/ deg K, correspondlng to the high temperature expression above. The agreement is within experimental error except at the very lowest temperatures obtained. The effective field at the nucleus of the terbium atom can be calculated and is found to be H/sub eff/= 4 x 10/sup 6/ gauss. (auth)
Date: October 1, 1961
Creator: Heltemes, E. C. & Swenson, C. A.
System: The UNT Digital Library
Thermodynamics of Extraction of Nitric Acid by Tri-n-Butyl Phosphate- Hydrocarbon Diluent Solutions. Iii. Comparison of Literature Data (open access)
PROPERTIES OP LIQUID HELIUM-THREE IN THE TWO-BODY CORRELATION APPROXIMATION. I (open access)

PROPERTIES OP LIQUID HELIUM-THREE IN THE TWO-BODY CORRELATION APPROXIMATION. I

This is the first of two papers in which the low-temperature properties of liquid He{sup 3} are to be calculated in the thermodynamically consistent 'T-matrix' approximation. The set of coupled integral equations which are to be solved is exhibited in Part A of this paper. Part B of this paper is devoted to a preliminary, zero-temperature calculation which employs the additional approximations of using separable potentials and a noninteracting spectral function to define the interaction of two particles in the medium: the <T>{sub 0} approximation. In this approximation they obtain a spectral function for the quasi particles which they expect to display general features in common with those of the actual spectral function. Using this spectral function, they calculate the thermodynamic properties of the system and find that they compare favorably to those obtained in other calculations.
Date: November 17, 1965
Creator: Beck, Donald E. & Sessler, Andrew M.
System: The UNT Digital Library
Coherent Electromagnetic Effects in High-Current Particle Accelerators: [Part] 3. Electromagnetic-Coupling Instabilities in a Coasting Beam (open access)

Coherent Electromagnetic Effects in High-Current Particle Accelerators: [Part] 3. Electromagnetic-Coupling Instabilities in a Coasting Beam

The electromagnetic interaction of an intense relativistic coasting beam with itself, including the effect of a confining nonperfect vacuum tank, or a quiescent rf cavity, is investigated theoretically. It is shown that the resonances that may occur between harmonics of the particle circulation frequencies and the electromagnetic modes of the cavities can lead to a longitudinal instability of the beam. A criterion for stability of the beam against such longitudinal bunching is obtained as a restriction on the shunt impedance of the rf cavity, or the Q of the vacuum tank. This criterion contains the energy spread and intensity of the coasting beam, as well as the parameters of the accelerator. Numerical examples are given which indicate that in general the resonances with the vacuum tank will not cause instabilities, while those with an rf cavity can be prevented from causing instabilities by choosing the shunt impedance at a sufficiently low but still convenient value.
Date: August 4, 1960
Creator: Laslett, L. J.; Neil, V. Kelvin & Sessler, A. M.
System: The UNT Digital Library