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AN INFORMATION STORAGE AND RETRIEVAL SYSTEM FOR IRRADIATION EFFECTS IN METALS

Description: 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 plu… more
Date: August 15, 1963
Creator: Bush, S. H.
Partner: UNT Libraries Government Documents Department
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Secondary Isotope Effects in Molecular Structure

Description: 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 me… more
Date: June 15, 1962
Creator: Bartell, L. S.
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

Electrical and Magnetic Properties of Holmium Single Crystals

Description: 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… more
Date: September 15, 1962
Creator: Strandburg, D. L.; Legvold, S. & Spedding, F. H.
Partner: UNT Libraries Government Documents Department
open access

BREMSSTRAHLUNG IN A DENSE PLASMA

Description: The bremsstrahlung emitted by an electron scattered in a Coulomb field was first calculated by Bethe and Heitler. The total cross section for production of photons with wave number between k and k + dk by a nonrelativistic electron of kinetic energy {epsilon} is d{sigma}/dk dk = 16/3 Z{sup 2}r{sub 0}{sup 2} (e{sup 2}/hc) (mc{sup 2}/{epsilon})log ({radical} {epsilon}/hck + {radical} {epsilon}/hck -1) dk/k, where Ze is the charge of the (heavy) ion, and r{sub 0} is the classical electron radius. … more
Date: January 15, 1963
Creator: Stack, John D. & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department
open access

OXYGEN-17 NMR SHIFTS CAUSED BY Cr$sup ++$ IN AQUEOUS SOLUTIONS

Description: Cr{sup++} in solution produces a paramagnetic shift in the NMR absorption of 0{sup17} in C1O{sub4}{sup-}, as well as the expected paramagnetic shift for 0{sup17} in H{sub2}O. As the concentration of C1O{sub4}{sup-} increases, the shift in the H{sub2}O{sup17} absorption is diminished, and eventually changes sign. The effects are ascribed to preferential replacement by C1O{sub4}{sup-} of water molecules from the axial positions in the first coordination sphere about Gr{sup++}.
Date: February 15, 1963
Creator: Jackson, J.A.; Lemons, J.F. & Taube, H.
Partner: UNT Libraries Government Documents Department
open access

PERTURBATION THEORY OF MANY-BOSON SYSTEMS

Description: A noncanonical transformation of the boson creation and annihilation operators is performed in order to obtain a Hamiltonian which can be treated by the standard methods of field-theoretic perturbation theory. The standard results of Belyaev (with a slight modification) are rederived by this technique. (auth)
Date: December 15, 1962
Creator: Kromminga, A.J. & Bolsterli, M.
Partner: UNT Libraries Government Documents Department
open access

Electrical Resistivity of Lanthanum, Praseodymium, Neodymium, and Samarium

Description: The electrical resistivities of polycrystalline samples of La, Pr, Nd, and Sm are reported in the temperature range 1.3 to 300 deg K. La exhibits a superconducting transition at 5.8 deg K. The curve for Pr has slope changes at 61 and 95 deg K. The Nd curve shows small jumps at 5 and 20 deg K. Sm shows slope changes at 14 and 106 deg K. (auth)
Date: March 15, 1961
Creator: Alstad, J. K.; Colvin, R. V.; Legvold, S. & Spedding, F. H.
Partner: UNT Libraries Government Documents Department
open access

BETA RADIATION PROCESSING AT RIGOROUS CONDITIONS

Description: An investigation was conducted on the impossible use of beta radiation to promote chemical reactions at high temperatures and pressures. The advantages of beta sources over other radiation sources are enumerated. A radiation processing apparatus is described which allows operations to 10,000 psi and 500 deg C and uses 90 C of Sr/sup 90/-Y/sup 90/. The dosimetry of the source was accomplished with an iodineheptane system, and the mean dose rate within the chemical reactor was determined to be 0.… more
Date: November 15, 1963
Creator: Yavorsky, P M & Gorin, E
Partner: UNT Libraries Government Documents Department
open access

EXCHANGE INTERACTION BETWEEN CONDUCTION ELECTRONS AND MAGNETIC SHELL ELECTRONS IN RARE-EARTH METALS

Description: The interaction Hamiltonian for the Coulomb exchange effect between conduction electrons and magnetic-shell electrons in rare-earth metals was derived from first principles. The approximations under which the interaction can be represented by the product of electron and ion spin vectors are exhibited. (auth)
Date: January 15, 1961
Creator: Liu, S. H.
Partner: UNT Libraries Government Documents Department
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