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306,149 Matching Results

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(open access)

Pot Calcination Performance During First Radioactive Tests in Waste Solidification Engineering Prototypes: Waste Solidification Program. Vol. 4.

None

Date: January 1, 1968

Creator: McElroy, J. L.; Cooley, C. R.; DeMier, W. V.; Mendel, J. E.; Suddath, J. C. & Blomeke, J. O.

Object Type: Report

System: The UNT Digital Library

(open access)

Numerical study of the NOL large-scale gap test

The NOL large-scale gap test has been modeled numerically using the LASL reactive hydrodynamics code 2DE with Forest Fire burn rates. The model gives good agreement between calculated and experimental critical gap values for VTQ-2 and Composition B. The calibration of peak pressure in the gap versus gap length has been obtained from these calculations, and is in good agreement with the published experimental curve. The two-dimensional nature of the gap test is evident from the curvature of the shock wave in the gap and test sample, and from the observed distance of run to detonation in the test samples.

Date: January 1, 1980

Creator: Bowman, A.L.

Object Type: Report

System: The UNT Digital Library

(open access)

Surprising patterns of CMOS susceptibility to ESD and implications on long-term reliability

CMOS electrostatic discharge (ESD) failures in a product where, by design, the device input terminals are not accessible to ESD led to this study of device susceptibility and an analysis of the long-term reliability of devices in assemblies from that production line. Some surprising patterns of device susceptibility are established and it is shown that the probability of long-term failure in devices whose electrical characteristics have been degraded by electrostatic discharge is small.

Date: January 1, 1980

Creator: Schwank, J.R.; Baker, R.P. & Armendariz, M.G.

Object Type: Article

System: The UNT Digital Library

(open access)

Use of Analog Computers for Simulating the Movement of Isotopes in Ecological Systems

None

Date: January 24, 1962

Creator: Neel, R. B. & Olson, J. S.

Object Type: Thesis or Dissertation

System: The UNT Digital Library

(open access)

Alkali sorber (RABSAM), September 1, 1990--August 30, 1991

The objective of this work is to develop a regenerable activated-bauxite sorber alkali monitor that requires no high-temperature/high-pressure sampling line for the reliable in situ measurement of alkali-vapor concentration in the exhaust from the pressurized fluidized-bed combustion of coal. 11 refs., 2 figs., 1 tab.

Date: January 1, 1991

Creator: Lee, S. H. D. & Swift, M. W.

Object Type: Article

System: The UNT Digital Library

(open access)

Damage nucleation in Si during ion irradiation

Damage nucleation in single crystals of silicon during ion irradiation is investigated. Experimental results and mechanisms for damage nucleation during both room and liquid nitrogen temperature irradiation with different mass ions are discussed. It is shown that the accumulation of damage during room temperature irradiation depends on the rate of implantation. These dose rate effects are found to decrease in magnitude as the mass of the ions is increased. The significance of dose rate effects and their mass dependence on nucleation mechanisms is discussed.

Date: January 1, 1984

Creator: Holland, O.W.; Fathy, D. & Narayan, J.

Object Type: Article

System: The UNT Digital Library

(open access)

Statistical magnetohydrodynamics and reversed-field-pinch quiescence

A statistical model of a bounded, incompressible, cylindrical magnetofluid is presented. This model predicts the presence of magnetic fluctuations about a cylindrically-symmetric, Bessel-function-model, mean magnetic field, which satisfies del x <B> = ..mu.. <B>. As theta ..-->.. 1.56, the model predicts that the significant region of the fluctuation spectrum narrows down to a single (coherent) m = 1 mode. An analogy between the Debye length of an electrostatic plasma and ..mu../sup -1/ suggests the physical validity o the model's prediction of <deltaB(r)deltaB(r')> when /r - r'/ greater than or equal to ..mu../sup -1/.

Date: January 1, 1982

Creator: Turner, L.

Object Type: Article

System: The UNT Digital Library

(open access)

Geothermal resources in California: the problems and the potential

The report is presented under the following section headings: introduction; conclusions and recommendations; legislative activity in 1973; United Nations Geothermal Conference; International Geothermal Conference--1975; National Conference on Geothermal Energy, May 10--11, Palm Springs, Calif.; Imperial Valley field trip and joint interim hearing October 16--17, 1973 (Senate Committee on Natural Resources and Wildlife on Senate Bill 577 in San Diego); hearing of the Subcommittee on Geothermal Resources and the Senate Committee on Public Utilities and Corporations, Nov. 12, 1973 in San Francisco (public access to steam at The Geysers); hearing of the Senate Committee on Natural Resources and Wildlife on the continued availability of natural gas and other sources of energy, Nov. 15, 1973, in Martinez, Calif; and Appendix. (JGB)

Date: January 1, 1973

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

Tumor production in Syrian hamsters following inhalation of PuO/sub 2/--ZrO/sub 2/ aerosol

Syrian golden hamsters of both sexes were exposed to aerosols of ZrO/sub 2/ containing PuO/sub 2/. The starting material in the aerosol generator also had a small amount of /sup 57/Co added as a tracer. The mixture of all three constituents was nebulized and the droplets passed through a heating column at 1000/sup 0/C. Aerosol sampling was accomplished with a cascade impactor and electrostatic precipitator. The median aerodynamic diameters in all inhalation runs were approximately 2 ..mu..m with a geometric standard deviation of 2. One exposed group of 60 hamsters had 6-day lung burdens averaging 100 nCi. This group had a lung tumor incidence of 44% with an even distribution of adenomas and carcinomas. Two other groups had average 6-day lung burdens of 80 to 90 nCi plus 55 nCi of intravenously injected spheres localized in the lung. These animals had tumor incidences of approximately 30%.

Date: January 1, 1978

Creator: Thomas, R. G. & Smith, D. M.

Object Type: Article

System: The UNT Digital Library

(open access)

Validation and sensitivity of a simulated photograph technique for visibility modeling

The Los Alamos Scientific Laboratory (LASL) visibility model is capable of producing simulated before and after pictures that illustrate visual effects of smoke plumes. Although the model has been under development for a few years, until recently there had been very little testing of the model against field experience or testing of sensitivity of the model results to numerical approximations used in the model. Further validation and sensitivity testing of the LASL model began in late 1979. The work focused on three areas: comparison of the LASL model results with plumes encountered in the field, comparison of LASL background-atmosphere model results with measured sky intensities, and examination of the variation of model results with changes in the numerical approximations. The field study took place during August of 1979 in the vicinity of coal-fired power plants in northwestern New Mexico and northern Arizona. Telephotometer, NO/sub X/ plume measurements, and aerosol size distribution measurements were made in the plumes of three different coal-fired power plants. Photographs were taken of the plumes, and simulated photographs were prepared by the model. Light intensities calculated by the background radiative transfer model were compared to measured light intensities in a very clean atmosphere and in a …

Date: January 1, 1980

Creator: Williams, M.; Chan, L.Y. & Lewis, R.

Object Type: Article

System: The UNT Digital Library

(open access)

Programmable multi-timer for TRU waste analysis applications

A programmable, multiple-function timing module has been developed for use in transuranic (TRU) waste analysis applications at the Idaho National Engineering Laboratory. The Programmable Multi-Timer (PRMT) is an expanded version of a module originally built for accelerator-based active photon interrogation experiments. During the course of the experiments, it became obvious that a more versatile timer was needed to meet several unforeseen requirements. The PRMT was designed to meet the new requirements and to serve as a general-purpose timing module for other applications.

Date: January 1, 1981

Creator: Lawrence, R.S.; Nieschmidt, E.B. & Tsang, F.Y.

Object Type: Article

System: The UNT Digital Library

(open access)

A Novel Coal Feeder for Production of Low Sulfur Fuel

During the past three months, the coal feeding system has been tested and currently undergoing evaluation at the University of Cincinnati. The system consists primarily of an auger feed tube which is used to both convey and provide desulfurization of a high sulfur coal feedstock. The coal is conveyed at temperatures ranging from 350 to 550{degrees}C and under normal atmospheric pressure. Under these mild processing conditions, the coal partially pyrolizes and emits sulfur in the form of hydrogen sulfide while maintaining a relatively high heating value in the char product. The evolved gases are evacuated from the reactor (the feed tube) to another absorbing bed where H{sub 2}S reacts with the sorbent, usually lime or limestone. The resultant sorbent utilization is substantially higher than the values found in current dry scrubbing system and the produced low-sulfur char may then be used in a conventional steam boiler.

Date: January 1, 1990

Creator: Khang, S. J. & Keener, T. C.

Object Type: Report

System: The UNT Digital Library

(open access)

Institutional research and development, FY 1987

The Institutional Research and Development program at Lawrence Livermore National Laboratory fosters exploratory work to advance science and technology, disciplinary research to develop innovative solutions to problems in various scientific fields, and long-term interdisciplinary research in support of defense and energy missions. This annual report describes research funded under this program for FY87. (DWL)

Date: January 1, 1987

Creator: Struble, G. L.; Lawler, G. M.; Crawford, R. B.; Kirvel, R. D.; Peck, T. M.; Prono, J. K. et al.

Object Type: Report

System: The UNT Digital Library

(open access)

Electronic band structure and optical properties of the cubic, Sc, Y and La hydride systems

Electronic band structure calculations are used to interpret the optical spectra of the cubic Sc, Y and La hydride systems. Self-consistent band calculations of ScH/sub 2/ and YH/sub 2/ were carried out. The respective joint densities of states are computed and compared to the dielectric functions determined from the optical measurements. Additional calculations were performed in which the Fermi level or band gap energies are rigidly shifted by a small energy increment. These calculations are then used to simulate the derivative structure in thermomodulation spectra and relate the origin of experimental interband features to the calculated energy bands. While good systematic agreement is obtained for several spectral features, the origin of low-energy interband transitions in YH/sub 2/ cannot be explained by these calculated bands. A lattice-size-dependent premature occupation of octahedral sites by hydrogen atoms in the fcc metal lattice is suggested to account for this discrepancy. Various non-self-consistent calculations are used to examine the effect of such a premature occupation. Measurements of the optical absorptivity of LaH/sub x/ with 1.6 < x < 2.9 are presented which, as expected, indicate a more premature occupation of the octahedral sites in the larger LaH/sub 2/ lattice. These experimental results also suggest that, …

Date: January 1, 1980

Creator: Peterman, D. J.

Object Type: Report

System: The UNT Digital Library

(open access)

The (t,d) reaction on the Ni isotopes with polarized tritons

The (t vector,d) reaction has been measured on targets of /sup 58/ /sup 60/ /sup 62/ /sup 64/Ni with 17 MeV polarized tritons. Spectroscopic factors, angular momentum and total spin transfer were obtained from the differential cross section and A/sub y/ values of levels up to 3.5 MeV in excitation energy. The present (t,d) measurement enables a better description of the 9/2/sup +/ and 5/2/sup +/ states which show significant shell crossing effects as a function of increasing neutron number.

Date: January 1, 1980

Creator: Flynn, E. R.; Cizewski, J. A.; Brown, R. E.; Hardekopf, R. A. & Sunier, J. W.

Object Type: Article

System: The UNT Digital Library

(open access)

Redox reactions involving chromium, plutonium, and manganese in soils

Plutonium speciation in soils is discussed. Chromium was selected as a model for studying soil Pu. Similarities between Cr and Pu are pointed out, and a hypotheses concerning Pu speciation in soils is presented. Findings from Cr oxidation studies that may be relevant to the problem of Pu oxidation in soils are discussed. (JGB)

Date: January 1, 1979

Creator: Amacher, M.C. & Baker, D.E.

Object Type: Report

System: The UNT Digital Library

(open access)

Supporting Analysis for Thermal Suitability of Fuel Elements for SM-1A Core I Loading

A recommended SM-1A Core I loading chart was derived from available, metallurgically acceptable elements at the SM-1A and SM-1 sites. The derivation was based on local thermal and hydraulic considerations of minimum elementto- element coolant channel clearances. These clearances were determined from field inspection measurements of outer fuel plate spacing, as modified by analytical calculations of plate ripple growth during exposure to reactor operating thermal stresses. (auth)

Date: January 10, 1962

Creator: Brondel, J. O.

Object Type: Report

System: The UNT Digital Library

(open access)

Chemical Technology Division, Unit Operations Section Monthly Progress Report, June 1961

An interfacial viseometer was built for use in an interfacial phenomena study. Installation of a 6-in.-ID foam separation column system was completed. The dispersiondrying-sintering characteristics of six low-nitrate batches of thoria sol material were studied. The average effective porosity of the CuO pellets used for reactor helium purification was determined to be 0.0545 for H/ sub 2/ transport and 0.0526 for CO transport. In continuous Zirflex dissolution studies, no H/sub 2/O/sub 2/ decomposition was observed when 10% H/sub 2/O/sup 2 was fed into boiling dissoivent through a water-cooled nozzle and the oxygen concentration in the scrubbed off-gas could be used to control the H/sub 2/O/sub 2/ concentration in the dissolver. The free fluoride in Zirflex solutions must be maintained above 1 molar in order to prevent uranium precipitation at low concentrations of uranium even though the F/sup -//U ratio exceeds 100. Chopped stainless steel-clad UO/sub 2/ sections were leached in a 4 stage pyrex leacher model using 6, 7, and 8 M nitric acid as the dissolvent. The temperature distribution expected within fuel elements consisting of square arrays of tubes was calculated for shipping conditions assuming heat to be transferred only by radiation. HETS values were calculated for uranium stripping …

Date: January 23, 1962

Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.

Object Type: Report

System: The UNT Digital Library

(open access)

Vacuum ultraviolet electronic properties of liquids. Annual progress report, 1 November 1979-31 October 1980

Areas covered are: optical and dielectric properties of hexamethyl-phosphoric triamide; photoemission from uv irradiated liquids; photon and photoelectron mean free paths in liquids; properties of Kapton films; and uv transmission of polycyclic organic molecules. (GHT)

Date: January 1, 1980

Creator: Painter, L.R.

Object Type: Report

System: The UNT Digital Library

(open access)

Development of 400- to 450-MHz RFQ resonator-cavity mechanical designs

In the development of the radio-frequency quadrupole (RFQ) linac, the resonator cavity's mechanical design may be a challenge similar in magnitude to that of the development of the accelerator structure itself. Experience with the all-copper 425-MHz RFQ proof-of-principle linac has demonstrated that the resonator cavity must be structurally stiff and easily tunable. This experience has led to development of copper-plated steel structures having vanes that may be moved within a cylinder for tuning. Design of a flexible vane-to-cylinder radio-frequency (rf) joint, the vane, and the cylinder has many constraints dictated by the small-diameter cavities in the 400-MHz-frequency region. Two types of flexible, mechanical vane-to-cylinder rf joints are being developed at Los Alamos: the C-seal and the rf clamp-joint.

Date: January 1, 1982

Creator: Hansborough, L.D.

Object Type: Report

System: The UNT Digital Library

(open access)

Alignment and orientation in ion/endash/atom collisions

Recent progress in the theoretical study of alignment and orientation in atom-atom and ion-atom collisions at intermediate energies is reviewed. Recent systematic studies of the alignment and orientation of electronic charge cloud distributions of excited states resulting from such collisions clearly have provided more detailed information about the underlying collision dynamics. However, since accurate determination of these parameters is quite difficult, both theoretically and experimentally, a close collaboration between theory and experiment is necessary for a deeper understanding of the collision dynamics. A more complete approach, where the full density matrix is determined, is also discussed.

Date: January 1, 1987

Creator: Kimura, M. & Lane, N.F.

Object Type: Article

System: The UNT Digital Library

(open access)

Stochastic model of radioiodine transport

A research project has been underway at the Oak Ridge National Laboratory with the objective to evaluate dose assessment models and to determine the uncertainty associated with the model predictions. This has resulted in the application of methods to propagate uncertainties through models. Some techniques and results related to this problem are discussed.

Date: January 1, 1980

Creator: Schwarz, G. & Hoffman, F.O.

Object Type: Article

System: The UNT Digital Library

(open access)

Lost circulation technology development status

Lost circulation is the loss of drilling fluid from the wellbore to fractures or pores in the rock formation. In geothermal drilling, lost circulation is often a serious problem that contributes greatly to the cost of the average geothermal well. The Lost Circulation Technology Development Program is sponsored at Sandia National Laboratories by the US Department of Energy. The goal of the program is to reduce lost circulation costs by 30--50% through the development of mitigation and characterization technology. This paper describes the technical progress made in this program during the period April 1991--March 1992. 8 refs.

Date: January 1, 1992

Creator: Glowka, D. A.; Schafer, D. M.; Loeppke, G. E.; Scott, D. D.; Wernig, M. D. & Wright, E. K.

Object Type: Article

System: The UNT Digital Library

(open access)

Sonic enhanced ash agglomeration and sulfur capture

The major objective of the Phase 1 test program is to confirm the feasibility of the Manufacturing and Technology Conversion International, Inc. bimodal particle size approach to enhance particulate control by acoustic ash agglomeration. An ancillary objective of the Phase 1 effort is to demonstrate and confirm the feasibility of an acoustic field to enhance sulfur capture by increasing sorbent reactivity. Phase 1 tests are designed to cover the frequency range between 50 and 1400 Hz, establish monomodal baseline performance as a benchmark from which to measure the degree of enhancement expected from the bimodal approach, and, finally, to confirm the effectiveness of low-frequency fields over high-frequency fields for realistic particulate streams. The program will demonstrate the effectiveness of a unique approach which uses a bimodal distribution composed of large sorbent particles and fine fly ash particles to enhance ash agglomeration and sulfur capture at conditions found in direct coal-fired turbines. Under the impact of high-intensity sound waves, sorbent reactivity and utilization, it is theorized, will increase while agglomerates of fly ash and sorbents are formed which are readily collected in commercial cyclones. The work will extend the concept from the demonstration of feasibility (Phase 1), through proof-of-concept (Phase 2) …

Date: January 1, 1991

Creator: unknown

Object Type: Report

System: The UNT Digital Library

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