21 Matching Results

Search Results

Results: 1 - 21
open access

Theory of the temperature dependence of positron bulk lifetimes-implications for vacancy formation enthalpy measurements via positron experiments

Description: Temperature dependent effects, which may have a bearing on determinations of vacancy formation enthalpies in metals by positron annihilation, have been observed in certain metals. These effects have been observed to occur both at temperatures below those at which positron annihilation is most sensitive to equilibrium vacancies and at temperatures well within the vacancy-sensitive region. The effect of thermal lattice displacements on positron lifetimes in metals was investigated to help underst… more
Date: February 1, 1977
Creator: Tam, S.W.; Sinha, S.K. & Siegel, R.W.
Partner: UNT Libraries Government Documents Department
open access

Weak interaction: past answers, present questions

Description: A historical sketch of the weak interaction is presented. From beta ray to pion decay, the V-A theory of Marshak and Sudarshan, CVC principle of equivalence, universality as an algebraic condition, PCAC, renormalized weak Hamiltonian in the rehabilitation of field theory, and some current issues are considered in this review. 47 references. (JFP)
Date: February 1, 1977
Creator: Ne'eman, Y.
Partner: UNT Libraries Government Documents Department
open access

Decomposition of lignin and cellobiose in relation to the enzymatic hydrolysis of cellulose

Description: Studies are reported on the use of fungal ..beta..-glucosidase in conjunction with Trichoderma viride cellulase and the search for an effective enzyme system for lignin degradation. ..beta..-glucosidase is of potential benefit in cellulose hydrolysis by catalyzing the hydrolysis of cellobiose to glucose thereby reducing product inhibition and producing a higher glucose yield. Removal of lignin from cellulosic material makes the cellulose more accessible to hydrolyzing enzymes. Hydrolysis studie… more
Date: February 1, 1977
Creator: Yamanaka, Y.; Carroad, P. A.; Riaz, M. & Wilke, C. R.
Partner: UNT Libraries Government Documents Department
open access

Range of investigation of a borehole gravimeter

Description: Concepts of the range of investigation of a borehole gravimeter are reviewed. It is shown that the maximum sensitivity to a mass point at a horizontal distance R from a borehole occurs at a vertical distance Z = R/..sqrt..2. Thus, the angle of maximum sensitivity is about 55/sup 0/ from the vertical. It is also shown that the absolute value of the gravitational effect decreases with increasing R. There are two maxima of the vertical gradient of gravity (at Z = 0 and at Z = ..sqrt../sup 3///sub … more
Date: February 22, 1977
Creator: Hearst, J. R.
Partner: UNT Libraries Government Documents Department
open access

Laser light absorption and harmonic generation due to self-generated magnetic fields

Description: It is shown that self-generated magnetic fields can play a significant role in laser light absorption. Even normally incident light will then be resonantly absorbed. Computer simulations and theoretical estimates for this absorption and the concomitant harmonic generation are given for parameters characteristic of some recent experiments.
Date: February 1, 1977
Creator: Kruer, W. L. & Estabrook, K. G.
Partner: UNT Libraries Government Documents Department
open access

Overview of advanced process control in welding within ERDA

Description: The special kinds of demands placed on ERDA weapons and reactors require them to have very reliable welds. Process control is critical in achieving this reliability. ERDA has a number of advanced process control projects underway with much of the emphasis being on electron beam welding. These include projects on voltage measurement, beam-current control, beam focusing, beam spot tracking, spike suppression, and computer control. A general discussion of process control in welding is followed by … more
Date: February 11, 1977
Creator: Armstrong, R. E.
Partner: UNT Libraries Government Documents Department
open access

Influence of plutonium recycle on the radioactive waste management system

Description: The effect that variations in the back-end of the fuel cycle have upon radioactive waste characteristics is of increasing interest. An overview treatment of the characteristics for the once-through cycle, recycle of uranium only, and recycle of uranium and plutonium modes of operation is presented. Characteristics which are considered include waste volumes, heat generation, neutron source strength, specific activities, and radioactive airborne releases.
Date: February 1, 1977
Creator: Kreiter, M R; Fleischman, R M & Muckerheide, W A
Partner: UNT Libraries Government Documents Department
open access

Phase behavior and radiation effects in high level waste class

Description: Results are presented that demonstrate that detailed and reproducible data can be obtained for complex waste glasses. For the major glass composition examined, thermal treatment was shown to cause formation of several crystalline phases which contribute to an increased leachability. Although not discussed in detail here, Zn/sub 2/SiO/sub 4/ formation results in microcracking due to a thermal expansion mismatch with the glass matrix, and SrMoO/sub 4/ has a higher leachability than the glass matr… more
Date: February 1, 1977
Creator: Turcotte, R P & Roberts, F P
Partner: UNT Libraries Government Documents Department
open access

Summary review of rock mechanics workshop on radioactive waste disposal

Description: Presentations, critiques and recommendations for the disposal of commercial radioactive waste based upon an analysis of the information presented at the Rock Mechanics Review/Workshop, Denver, Colorado, December 16-17, 1976 are summarized. The workshop, comprised of both formal and informal sessions, with about 50 participants, was hosted by RE/SPEC Inc. and Dr. Paul F. Gnirk, President and was sponsored by the Office of Waste Isolation (OWI), led by Dr. William C. McClain. The panel of reviewe… more
Date: February 7, 1977
Creator: Carter, N. L.; Goodman, R. E. & Merrill, R. H.
Partner: UNT Libraries Government Documents Department
open access

Luminescence studies of oxygen absorption on thorium

Description: The interaction of oxygen with a thorium metal surface is being studied by monitoring the luminescence of thorium in an electron beam. By combining luminescence measurements with Auger electron spectroscopy data, it is possible to distinguish between processes that depend upon the oxygen pressure at the sample surface, and those that depend only upon the amount of adsorbed oxygen.
Date: February 15, 1977
Creator: Bastasz, R.; Colmenares, C. A.; Smith, R. L. & Somorjai, G. A.
Partner: UNT Libraries Government Documents Department
open access

Time for atomic and molecular data bases is now (an overview of data management research at LLL)

Description: Two numerical data bases of atomic and molecular (A and M) data required for laser-induced fusion studies were created. One file contains primarily atomic energy levels and atomic transition data released by Charlotte E. Moore in NBS publications. The second file is based on the spectroscopic constants for more than 1000 molecular levels of approximately 160 heteronuclear diatomic molecules prepared by S. N. Suchard. Additional data bases are contemplated in support of the accelerating research… more
Date: February 1, 1977
Creator: Hampel, V. E. & Henry, E. A.
Partner: UNT Libraries Government Documents Department
open access

Seminar proceedings: I. Pulsed neutron uranium borehole logging with prompt fission neutrons (PFN). II. Neutron tube technology for PFN logging equipment

Description: This is the first of a series of seminars on pulsed neutron logging of uranium boreholes by the Prompt Fission Neutron Technique, and on neutron tube technology. The purpose of these seminars is to aid in the transfer of technology from government-sponsored research to private industry utilization. The documentations in this report are extended abstracts of the presentations given at the seminars. Separate abstracts were prepared.
Date: February 1, 1977
Partner: UNT Libraries Government Documents Department
open access

Corrosion and ESCA studies of uranium after exposure to an RF discharge

Description: Corrosion of uranium in O/sub 2/ or H/sub 2/O atmospheres can be inhibited by first oxidizing the surface and then exposing it to organic vapors at temperatures near 400/sup 0/C. There is evidence that a polymeric material is formed on the surface and that it may be responsible for the corrosion inhibition. Polymer coatings can also be prepared using an RF discharge. This paper describes experiments in which uranium surfaces were exposed to an RF discharge and then evaluated as to their corrosi… more
Date: February 10, 1977
Creator: Happe, J. A.; Colmenares, C. A.; McCreary, T. & Somorjai, G. A.
Partner: UNT Libraries Government Documents Department
open access

Implications of plutonium utilization strategies on the transition from a LWR economy to a breeder economy

Description: The plutonium interface between the LWR and LMFBR fuel cycles is examined for typical nuclear growth projections both with and without plutonium recycle in LWRs. In order to guarantee a fuel supply for projected LMFBR growth rates, significant multiple Pu recycle in LWRs will not be possible. However, about 78% of the benefit of multiple plutonium recycle between now and the turn of the century is realized by one recycle and then stockpiling spent MOX for the LMFBR. LMFBR reprocessing schecules… more
Date: February 1977
Creator: Newman, D. F.; Fleischman, R. M. & White, M. K.
Partner: UNT Libraries Government Documents Department
open access

Path integral quantization of solitons

Description: A review of some recent work on the collective coordinate approach to perturbation expansion about soliton solutions is presented. Consistent formulation of the method in framework of the Feynman path integral quantization procedure is described. As an illustrative application one discusses in detail a perturbation expansion for scattering of solitons.
Date: February 1, 1977
Creator: Jevicki, A.
Partner: UNT Libraries Government Documents Department
open access

Data Model of the BNL Archive and Dissemination System

Description: The Data Model, i.e., the information content of the data base as it is viewed by the users, of the BNL Archive and Dissemination System is presented. The syntax of the data model is stated in BNF form, and the semantic meaning is discussed. Examples of the use of the data model are given. 3 figs.
Date: February 1, 1977
Creator: Heller, J & Osterer, L
Partner: UNT Libraries Government Documents Department
open access

Radioactive waste isolation: a national problem

Description: The principal aim of the National Waste Terminal Storage (NWTS) program is to develop repositories in several different rock formations in various parts of the country. Rocks such as salt, shale, limestone, and granite may qualify as host media for the disposition of radioactive wastes in the proper environments. In general, the only requirement for any rock formation or storage area is that it be able to contain any emplaced wastes for so long as it takes for the radioactive materials to decay… more
Date: February 22, 1977
Creator: Lomenick, T. F.
Partner: UNT Libraries Government Documents Department
open access

Surface and impurity studies in ORMAK and ISX

Description: The ORMAK vacuum liner is constructed of stainless steel overcoated with a thin platinum diffusion barrier and a final layer of gold. Gold was selected as the vacuum surface because it is chemically inert to the adsorption of common gases. However, gold surfaces do adsorb hydrocarbons, and carbon (along with oxygen) was the principal plasma contaminant during the first two years of ORMAK operation. Upon switching discharge-cleaning gases from hydrogen to oxygen, carbon levels dropped until carb… more
Date: February 1, 1977
Creator: Colchin, R. J.; Clausing, R. E.; Emerson, L. C.; Heatherly, L. & Isler, R. C.
Partner: UNT Libraries Government Documents Department
open access

Multiphoton resonances

Description: The long-time average of level populations in a coherently-excited anharmonic sequence of energy levels (e.g., an anharmonic oscillator) exhibits sharp resonances as a function of laser frequency. For simple linearly-increasing anharmonicity, each resonance is a superposition of various multiphoton resonances (e.g., a superposition of 3, 5, 7, . . . photon resonances), each having its own characteristic width predictable from perturbation theory.
Date: February 16, 1977
Creator: Shore, B. W.
Partner: UNT Libraries Government Documents Department
open access

BNL Archive and Dissemination System. [For accessing data files constructed at separate places and times]

Description: The Brookhaven National Laboratory Archive and Dissemination System (BNLADS) is designed to deal with the record keeping associated with archiving and disseminating sequential files through a computer network. This data base management system (DBMS) is implemented in a host language that is a subset of PL/I. The stored sequential files that can be dealt with by the BNLADS must be in character mode (ASCII, BCD, EBCDIC). The accessing of fields is specified by a format description which allows fo… more
Date: February 1, 1977
Creator: Abbey, S; Fuchel, K; Heller, J; Lin, K S & Osterer, L
Partner: UNT Libraries Government Documents Department
Back to Top of Screen