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Measurements of cosmic radiation dose in subsonic commercial aircraft compared to the city-pair dose calculation

Description: The radiation dose received by passengers during flight on conventional jet aircraft was determined as a function of exposure to cosmic radiation, solar radiation, flight time, and flight path. The dosimetric measurements were made with thermoluminescent dosimeters (TLD's) and with emulsions of three types sealed in plastic packets. These packets were sent by air mail back and forth from Berkeley, California to five cities and a dose sufficiently above background for a satisfactory measurement was accumulated by the TLD's on one round trip and by the emulsions on three round trips. It was concluded that both experiments and theory show that the total doses received at present day conventional jet aircraft altitudes are considerably higher than those encountered in supersonic flights at much higher altitudes, even though the dose rate is lower at these lower altitudes, when the longer time of exposure at the lower altitudes is taken into consideration. Computer programs used in the dose calculations are included. (CH)
Date: July 16, 1973
Creator: Wallace, R.
Partner: UNT Libraries Government Documents Department


Description: The prediction for the secondary neutron spectrum produced inside of-a thick shield is described. The multiplicity of cascade and evaporation secondaries as well as subsequent moderation of the secondary spectrum is described quantitatively. Experimental thick-target neutron yields, as well as Monte Carlo cascade data, are the basis for these estimates. (auth)
Date: October 11, 1962
Creator: Wallace, R. & Sondhaus, C.
Partner: UNT Libraries Government Documents Department

1D thermonuclear model for x-ray transients

Description: The thermonuclear evolution of a 1.41 M solar mass neutron star, with a radius of 14.3 km, accreting various mixtures of hydrogen, helium, and heavy elements at rates of 10/sup -11/ to 10/sup -10/ M solar mass/yr is examined, in conjunction with S.E. Woosley and T.A. Weaver, using a one-dimensional numerical model. We have ignored any effects due to general relativity or magnetic fields. Two cases shall be discussed. In both models, the accretion rate is such that the hydrogen shell burns to helium in steady state, with the hydrogen burning stabilized by the ..beta..-limited CNO cycle. A thick helium shell is produced, which is eventually ignited under extremely degenerate conditions, producing a thermonuclear runaway.
Date: January 1, 1982
Creator: Wallace, R.K.
Partner: UNT Libraries Government Documents Department

Choosing a document-formatting system

Description: The TeX system is chosen for formatting large computer code manuals to be initially implemented on VAX 11/780 and 8600 computers. The ''What You See Is What You Get'' word processor is recommended for producing small (5 to 10 page) reports and manuals and WordMARC is the preferred formatter in those situations. (DWL)
Date: January 1, 1986
Creator: Wallace, R.K.
Partner: UNT Libraries Government Documents Department

Waste Isolation Safety Assessment Program: a comparison of evapotranspiration estimates using DOE Hanford climatological data

Description: Three methods of estimating monthly values of evapotranspiration on a year-round basis were compared by using the same set of long-term Hanford climatological data as input. Potential evapotranspiration calculated by all three methods yielded an annual value 5 to 9 times the mean annual precipitation. One method yields a value for actual evapotranspiration and one yields a value for areal evapotranspiration. These are compared on a monthly basis and show quite different distributions over the year. The third method examined is relatively new, was calibrated using data from arid stations, and yields results that may be more truly representative of arid areas like Hanford.
Date: October 1, 1978
Creator: Wallace, R.W.
Partner: UNT Libraries Government Documents Department

Ion Exchange Membrane Processes

Description: Techniques were developed, and promising preliminary tests were completed in an exploratory study of the applicability of ion exchange membrane processes to such chemical operations as the separation of plutonium from uranium, the separation of americium from curium, the isolation of individual rare earths, the removal of strontium from process waste streams. This report discusses results of those tests.
Date: October 30, 2002
Creator: Wallace, R.M.
Partner: UNT Libraries Government Documents Department

Studies of Ruthenium(IV) and its Reduction Products in Perchlorate Solutions

Description: Ion exchange and membrane studies of Ru(IV) in perchloric acid indicate that the charge per atom is +1, the charge per species is +4, and that Ru(IV) is tetrameric. Coulometric, cyclic voltametric and spectrophotometric studies indicate that tetrameric Ru(IV) can be reduced reversibly by two, one-electron processes to species with formal oxidation states of 3.75 and 3.5. Ru(3.5) is reduced reversibly to a transient species of Ru(III) which rapidly converts to a stable polymeric species of Ru(III) that can be reoxidized to Ru(IV) only irreversibly. Stable Ru(III) can be electrochemically reduced to Ru(II).
Date: August 29, 2001
Creator: Wallace, R.M.
Partner: UNT Libraries Government Documents Department

Proceedings of the First International Symposium on the Biological Interpretation of Dose from Accelerator-Produced Radiation, Held at the Lawrence Radiation Laboratory, Berkeley, California, March 13--16, 1967

Description: The objective of the meeting was to provide a companion meeting to the ''First Symposium on Accelerator Radiation Dosimetry and Experience'' which was held November 3-5, 1965, at the Brookhaven National Laboratory. This first symposium was limited in scope to an intensified discussion of dosimetry techniques. The biology which is associated with high energy radiation was specifically excluded, since it was the original plan to hold a second symposium devoted entirely to biology. Thus the present Symposium was a sequel to the first and they were inseparable in their objectives. Since those attending the BNL Symposium were almost entirely health physicists with a background in physical science and actively engaged in the solution of radiation protection problems at high energy accelerators, it was felt that it would be necessary to begin the BID Symposium with a general review session on radiation biology, in order to provide a biological background for the proper understanding of the later sessions. This first session was arranged to give the health physicist a meaningful transition from fundamental radiobiological considerations to current new research activities in high energy biology. In our opinion, and also based on the comments of several of those attending these objectives were quite well attained. The talks by Bond, Robertson, Brustad, Wolff, and Patt were quite exhaustive as an introduction to the several areas of specialization in radiobiology. The overall purpose of the meeting was of course to inform the health physicists about the state of knowledge in advanced biological research as it might apply to their problems. It has often been said that it takes a long time for laboratory findings to be applied in practical situations, but this is certainly not true in radiobiology. Through this conference and others like it, the most recent understanding of high energy radiobiology is ...
Date: March 13, 1967
Creator: Wallace, R.
Partner: UNT Libraries Government Documents Department

Nuclear physics problems for accreting neutron stars

Description: The importance of p(e/sup -/nu)n and of (p,..gamma..) reactions on /sup 56/Ni during a thermonuclear runaway on a neutron star surface is pointed out. A fast 16-isotope approximate nuclear reaction network is developed that is suitable for use in hydrodynamic calculations of such events.
Date: January 1, 1983
Creator: Wallace, R.K. & Woosley, S.E.
Partner: UNT Libraries Government Documents Department

Understanding the Growth of the Cellulosic Ethanol Industry

Description: This report identifies, outlines, and documents a set of plausible scenarios for producing significant quantities of lignocellulosic ethanol in 2017. These scenarios can provide guidance for setting government policy and targeting government investment to the areas with greatest potential impact.
Date: April 1, 2008
Creator: Sandor, D.; Wallace, R. & Peterson, S.
Partner: UNT Libraries Government Documents Department

Effect of shale-water recharge on brine and gas recovery from geopressured reservoirs

Description: The concept of shale-water recharge has often been discussed and preliminary assessments of its significance in the recovery of geopressured fluids have been given previously. The present study uses the Pleasant Bayou Reservoir data as a base case and varies the shale formation properties to investigate their impact on brine and gas recovery. The parametric calculations, based on semi-analytic solutions and finite-difference techniques, show that for vertical shale permeabilities which are at least of the order of 10/sup -5/ md, shale recharge will constitute an important reservoir drive mechanism and will result in much larger fluid recovery than that possible in the absence of shale dewatering.
Date: January 1, 1985
Creator: Riney, T.D.; Garg, S.K. & Wallace, R.H. Jr.
Partner: UNT Libraries Government Documents Department

Thermonuclear model for x-ray transients

Description: The thermonuclear evolution of a 1.41 M sub solar neutron star accreting both solar and metal-deficient mixtures of hydrogen, helium, and heavy elements at rates ranging from about 10/sup -11/ to 10/sup -10/ M sub solar per year is examined using a one-dimensional numerical model. The metal deficient compositions may result either from placement of the neutron star in a binary system with a Population II red giant or from gravitational settling of heavy ions in the accreted material. For such accretion rates and metallicities, hydrogen burning, mediated by the ..beta..-limited CNO cycle, is stable and leads to the accumulation of a thick helium layer with mass 10/sup 23/ to 10/sup 25/ g and temperature 0.7 less than or equal to T/sub 8/ less than or equal to 1.2. Helium ignition occurs under extremely degenerate circumstances and is catastrophically violent. In the lower t helium shells this runaway is propagated as a convective deflagration, for the thicker layers a detonation front is set up which steepens into a strong relativistic shock wave in the neutron star envelope. In all models greatly super-Eddington luminosities in the outer layers of the neutron star lead to a sustained epoch of radiatively driven mass loss. Observationally, such models may correspond to rapid x-ray transients. The hopeless prospect for constructing a one-dimensional model for ..gamma..-ray bursts without magnetic field confinement is discussed and uncertainties pointed out in the strong screening correction for helium burning reaction.
Date: January 1, 1982
Creator: Wallace, R.K.; Woosley, S.E. & Weaver, T.A.
Partner: UNT Libraries Government Documents Department

Lithology and Reservoir Properties of the Big Lime, Keener, Big Injun, Weir, and Berea Horizons, Spruce Creek Oilfield, Ritchie County, West Virginia

Description: Report issued by the Bureau of Mines on the lithology of oilfields in Ritchie County, West Virginia. The different properties and characteristics of the core samples found in Ritchie County are presented, and compared. This report includes tables, and a map.
Date: 1963
Creator: McCord, Wallace R. & Eckard, William E.
Partner: UNT Libraries Government Documents Department

Comparative analysis of core drilling and rotary drilling in volcanic terrane

Description: Initially, the goal of this report is to compare and contrast penetration rates of rotary-mud drilling and core drilling in young volcanic terranes. It is widely recognized that areas containing an abundance of recent volcanic rocks are excellent targets for geothermal resources. Exploration programs depend heavily upon reliable subsurface information, because surface geophysical methods may be ineffective, inconclusive, or both. Past exploration drilling programs have mainly relied upon rotary-mud rigs for virtually all drilling activity. Core-drilling became popular several years ago, because it could deal effectively with two major problems encountered in young volcanic terranes: very hard, abrasive rock and extreme difficulty in controlling loss of circulation. In addition to overcoming these difficulties, core-drilling produced subsurface samples (core) that defined lithostratigraphy, structure and fractures far better than drill-chips. It seemed that the only negative aspect of core drilling was cost. The cost-per-foot may be two to three times higher than an ''initial quote'' for rotary drilling. In addition, penetration rates for comparable rock-types are often much lower for coring operations. This report also seeks to identify the extent of wireline core drilling (core-drilling using wireline retrieval) as a geothermal exploration tool. 25 refs., 21 figs., 13 tabs.
Date: April 1, 1987
Creator: Flynn, T.; Trexler, D.T. & Wallace, R.H. Jr. (ed.)
Partner: UNT Libraries Government Documents Department

Mathematical analysis of hydrogen mixing and diffusion in the vapor space of a high-level nuclear waste tank

Description: This paper presents mathematical analyses of the possible accumulation of radiolytically produced hydrogen in the vapor space in a tank storing liquid high-level radioactive waste. Under normal operating conditions, these tanks are continuously ventilated with air to ensure that the concentration of hydrogen never reaches its lower flammability limit (4%). These scenarios are considered in which it is postulated that hydrogen may accumulate and present a flammability hazard. These scenarios are stratification due to gravity, slow mixing when the ventilation system is operating, and slow mixing when the ventilation system is not operating. In all three cases, the analyses indicate that the accumulation of hydrogen is not likely and thus does not present a flammability problem so long as controls are in place to dilute its concentration to less than 4%.
Date: December 31, 1991
Creator: Bibler, N. E. & Wallace, R. M.
Partner: UNT Libraries Government Documents Department