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THE ABSORPTION OF NEUTRONS IN DOPPLER BROADENED RESONANCES

Description: A method is developed for the calculation of the effect of Doppler broadening of the absorption of the neutrons by a resonance absorber. Numerical values are given for the correction factors required in the interpretation of transmission experiments and self-indication experiments and for the self-shielding factors for slabs, spheres, cylinders, and homogeneous mixtures. (auth)
Date: October 15, 1954
Creator: Roe, G.M.

Absorption Spectra of Aromatic Disulfides

Description: The effect of solvents and temperature on the optical absorption spectrum of a number of substituted aromatic disulfides is reported. The problems offered by the disulfide link and the exchange reactions between disulfides, and between disulfides and thiols, are receiving increasing attention. Recently the base-catalyzed exchange between various alkyl disulfides and the corresponding thiols was studied by means of a radioactive-tracer technique. Our initial purpose was to extend these investigations to a large number of compounds in a variety of experimental conditions using a spectrophotometric technique that, if applicable, would have been incomparably faster.
Date: October 31, 1956
Creator: Fava, Antonio & Calvin, Melvin

ABSORPTION SPECTRA OF PLUTONIUM AND IMPURITY IONS IN NITRIC ACID SOLUTION

Description: The absorption spectra for Pu(III), (IV), (VI), and the red Pu(IV)- peroxy complex were determined in HNO/sub 3/ solution. Extinction coefficients for the above species of Pu were measured. Temperature has little effect on the spectra, but variation of acidity causes shifting of absorption peaks and some changes in the extinction coefficients. The absorption spectra and extinction coefficients in the region 390 to 1200 m mu were measured for chromic, nickelous, manganous, calcium, lanthanum, aluminum, ferrous. ferric, and permanganate ions in HNO/sub 3/ solutions. In addition, the effects of nitrite, oxalic acid, sulfamic acid, hydrogen peroxide, and various HNO/sub 3/ concentrations on the extinction coefficients of some of these ions were determined. The chromic, nickelous, ferrous, and permanganate ions, and ferric ion with oxalic acid, have sufficiently high extinction coefficients to cause inaccuracies in valence determinations of Pu in solutions containing high concentrations of these ions, unless corrections are made. (auth)
Date: July 31, 1956
Creator: Myers, M N

Abstract of Paper Presented at the Symposium on Metal ChelateChemistry at Brooklyn Polytechnic Institute on April 26, 1952

Description: The essential structural element which differentiates metal chelate compounds from metal coordination compounds, or metal complexes in general, is the existence of some linkage between two or more of the donor atoms in the first coordination sphere of the metal. It is the purpose of the present discussion to examine the influences that this structural factor may have upon the physical and chemical properties of chelate compounds. Examples of well known, simple coordination compounds involving a variety of donor atoms (Oxygen, nitrogen), as well as a variety of electrostatic situations are shown in the following formula. Below each one are listed a few corresponding chelate structures.
Date: April 1, 1952
Creator: Calvin, Melvin

Ac$sup 227$ AND Th$sup 228$ PRODUCTION AS A FUNCTION OF TIME FOR VARIOUS VALUES OF NEUTRON FLUX. (Information Report)

Description: The amount of Ac/sup 227/ per curie of Ra/sup 226/ was calculated for various values of neutron flux and various Irradiation times. The amount of Th/ sup 228/ produced per curie of Ra/sup 226/ and the percentage of Ac/sup 227/ converted to Th/sup 228/ relative to the total amount of Ac/sup 227/ produced were also calculated. (W.D.M.)
Date: August 28, 1952
Creator: Grove, G. R.; Russell, L. N. & Orr, S. R.

Acceleration of high-pressure-ratio single-spool turbojet engine as determined from component performance characteristics I : effect of air bleed at compressor outlet

Description: An analytical investigation was made to determine from component performance characteristics the effect of air bleed at the compressor outlet on the acceleration characteristics of a typical high-pressure-ratio single-spool turbojet engine. Consideration of several operating lines on the compressor performance map with two turbine-inlet temperatures showed that for a minimum acceleration time the turbine-inlet temperature should be the maximum allowable, and the operating line on the compressor map should be as close to the surge region as possible throughout the speed range. Operation along such a line would require a continuously varying bleed area. A relatively simple two-step area bleed gives only a small increase in acceleration time over a corresponding variable-area bleed. For the modes of operation considered, over 84 percent of the total acceleration time was required to accelerate through the low-speed range ; therefore, better low-speed compressor performance (higher pressure ratios and efficiencies) would give a significant reduction in acceleration time.
Date: March 10, 1953
Creator: Rebeske, John J , Jr & Rohlik, Harold E

Accelerations and passenger harness loads measured in full-scale light-airplane crashes

Description: From Introduction: "Light-airplane accident data, compiled by Crash Injury Research of Cornell University Medical College, indicate that human beings have often withstood declarations in excess of those imposed in airplane crashes involving extensive damage to the airplane structure (ref. 1). This study also correlates the extent of damage to the airplane structure with the injury incurred by the occupants during crash accidents."
Date: August 1953
Creator: Eiband, A Martin; Simpkinson, Scott H & Black, Dugald O

Accelerations in transport-airplane crashes

Description: From Introduction: "A study of crash-impact survival in light airplanes is reported in references 1 and 2. A similar study for fighter airplanes is reported in reference 3. This report discusses crash-impact survival in transport airplanes."
Date: February 1958
Creator: Preston, G Merritt & Pesman, Gerard J

Accepted Limit Values of Air Pollutants

Description: Report issued by the U.S. Bureau of Mines discussing, as stated in the introduction, the "accepted maximum permissible concentrations of air pollutants from the standpoints of health, damage to vegetation, damage to property, and requirements of industrial processes" (p. 1). This report includes tables.
Date: May 1954
Creator: Barkley, J. F.

ACCIDENT IN CONTINUOUS-DISSOLVER PILOT PLANT OF FLUORIDE VOLATILITY PROJECT ON MAY 15, 1957

Description: A series of explosions, estimated at five, occurred over a period of ten seconds within the continuous dissolver pilot plant, of the Fluoride Volatility Project on May 15, 1957. The explosive reactions occurred in the dissolver vessels as a result of violent chemical reactions between uranium and an interhalogen mixture. Just what the conditions were which triggered the explosions, have not been definitely established. Nevertheless, based upon the evidence which has been collected, several possible explanations, listed according to probability, are presented. A number of recommendations are included to be followed before operation of the pilot plant is resumed. These recommendations relate to additional laboratory research, equipment design, facility design, and use of a review committee. Safety rules for handling BrF/ sub 3/, BrF/sub 5/, ClF/sub 3/, and Br/sub 2/ are appended. (C.H.)
Date: July 10, 1957
Creator: Strickland, G.; Horn, F.L.; Johnson, R. & Dwyer, O.E.

ACCIDENTAL DISPERSION OF REACTOR POISONS AND THE CONTROLLED DISTANCE REQUIRED

Description: Two types of hypothetical reactor catastrophe are considered. In the first of these, the Boiling Accident,'' it is assumed that a fraction of the radioactive material in a reactor is released to the atmosphere at a steady rate over a period of hours. In the second, the Puff Accident,'' it is assumed that the release of the radioactive material takes place instantaneously.'' The following concepts are used as measures of the hazard existing outside the controlled plant area. Danger Distance,'' defined as that distance beyond which the fission product cloud becomes so dilute that it cannot cause death; Probabiiity of Death per Capita per Accident,'' which is a measure of the hazard to any individual; and Expectation Number of Deaths per Accident.'' which is a statistical measure of the hazard to the entire off-site populace. Three mechanisms for each type of catastrophe were considered: direct irradiation from the fission product cloud, inhalation of the air in the cloud, and rainout from the cloud followed by irradiation from the ground. Failout is not considered. for it requires that a very energetic explosion be assumed. It is concluded that the size of the plant should be set by the hazard of irradiation from the low- lying poison cloud produced in the boiling accident. A formula is proposed that permits the calculation of the controiled area that should exist around any reactor. Inversion and average meteoroiogy are analyzed in terms of their effect on off-site hazard. The same theory, utilizing the concepts of the probabiiity of death and the expectation number of deaths, is useful in estimating the hazard in the event a tank of H/sub 2/S, SO/sub 2/. or Cl ruptures. releasing to the atmosphere great quantities of gaseous poison. This problem is treated briefly at the end of the report. It ...
Date: March 1, 1958
Creator: Menegus, R.L. & Ring, H.F.

Accidental Radiation Excursion at the Y-12 Plant, June 16, 1958: Final Report

Description: This report describes the circumstances leading to the accident, attempts to reconstruct the nuclear reactivity conditions, and reviews the dosimetric means and results which were used to help determine the exposure of affected employees.
Date: September 12, 1958
Creator: Patton, F. S.; Bailey, J. C.; Callihan, A. D.; Googin, J. M.; Jasny, G. R.; McAlduff, H. J. et al.