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Second report of work carried out by the Institute for Nuclear Research for Los Alamos National Laboratory under Agreement 2493N0005-35

Description: This report provides information about work carried out to complete the tasks required of the Institute for Nuclear Research (INR) of the Russian Academy of Sciences in accordance with Agreement 2493N0005-35 with Los Alamos National Laboratory. This report details work carried out for the following parts of the agreement under Task Order 002: the INR shall measure the 51Cr source activity to an accuracy of at least 5% by measuring the amount of 51Cr activity remaining in each of the irradiated enriched 50Cr rods used in the Cr calibration experiment, this shall be done by direct counting using a high resolution Ge solid state detector; the INR shall measure the level of any residual radioimpurities in the 51Cr source by direct counting each of the rods of the 51Cr source using a high resolution Ge solid state detector. The following sections of this report shall constitute the following deliverables: a report describing the procedures used to measure the amount of residual 51Cr in the irradiated 50Cr rods, along with the value of the 51Cr source intensity determined using this method; a list of the long-lived radioimpurities and their intensities in the irradiated 50Cr rods.
Date: February 23, 1996
Creator: Gavrin, V. & Matveev, V.
Partner: UNT Libraries Government Documents Department

Results of the whole GALLEX experiment

Description: After 5.5 years of data taking, GALLEX ended its experimental phase. The solar neutrino production rate, 76.4 {+-} 8 SNU represents about 55% of the predicted rate. The As tests prove, at the 1% level, the reliability of the technique and the detection of {sup 51}Cr neutrino, with the nominal efficiency (93.0 {+-} 8%), control the response of the detector to neutrinos in the solar energy range.
Date: January 1, 1998
Creator: Cribier, M.
Partner: UNT Libraries Government Documents Department

Determination of the {sup 51}Cr source strength at BNL

Description: Neutron activation analysis (NAA) and {gamma}-ray counting have been used to measure the activity of 24 samples removed from the GALLEX radioactive Cr neutrino source. In 9.86% of the disintegrations, {sup 51}Cr decays with the emission of a 320-keV {gamma}-ray. Counting this {gamma}-ray provides a direct means to obtain the disintegration rates of the Cr samples. Based upon these disintegration rates, the authors obtain a strength of 63.1 {+-} 1.0 PBq for the entire Cr source. The Cr source activity has also been obtained through measuring the {sup 51}V content of each sample by means of NAA. {sup 51}V is the decay daughter for all decay modes of {sup 51}Cr. Through neutron bombardment, radioactive {sup 52}V is produced, which decays with the emission of a 1,434-keV {gamma}-ray. By counting this {gamma}-ray from NAA, they obtain a disintegration rate of 62.1 {+-} 1.0 PBq for the entire source. These values are consistent with all other measurements of the source strength done at other GALLEX Laboratories.
Date: November 1, 1995
Creator: Boger, J.; Hahn, R.L. & Chu, Y.Y.
Partner: UNT Libraries Government Documents Department

Preliminary results from the {sup 51}Cr neutrino source experiment in GALLEX

Description: The GALLEX collaboration performed a second {sup 51}Cr neutrino source experiment during fall 1995. The full results from this second source experiment will not be available before the end of 1996. Meanwhile, we present a short description and preliminary results in this informal note. The (preliminary) value of the activity obtained form direct measurements has been found equal to (68.7 {+-}0.7) PBq (with 1-sigma error). This value, which is about 10% higher than the activity of the first source, was achieved by optimizing the irradiation conditions in the Silo{acute e} reactor and doing a longer irradiation of the enriched chromium. Preliminary results show that the ratio, R, of the radiochemically determined activity from {sup 71}Ge counting (57.1 {+-} PBq) to the directly measured activity is (0.83 {+-} 0.10). The combined value of R for the two source experiments is (0.92 {+-} 0.08).
Date: September 1, 1996
Creator: Hampel, W.; Heusser, G. & Kiko, J.
Partner: UNT Libraries Government Documents Department

Corrosion Product Activity Distribution Across the Chemical Process System in the Consolidated Edison Thorium Reactor Plant

Description: ABS>A study was performed to determine the corrosion product and water impurity activities in the CETR Chemical Process System. These activities were calculated as functions of the reactor operating time, primary loop blowdown purification rate, and decay time following removal from the primary loop. For the design blowdown purification rate chosen, isotopes that are important to the design of radiation shielding include Co/sup 60/ and Co/sup 58/ Fe/sup 55/, Cr/ sup 51/, and Mn/sup 56/. A simplified mathematical model is used to represent the physical situation; however, the magnitude of the activities, taken at the end of core life to represent the most conservative case, is considered sufficiently accurate for engineering calculations. (auth)
Date: September 1, 1958
Partner: UNT Libraries Government Documents Department

Examination of Components for Crud and Corrosion 1-B Heat Exchanger Handhole Area. Core I, Seed 1. Test Results T-612080

Description: The extent and location of corrosion, crud deposits, and defects in the ends of the 1-B heat exchanger after removing the handhole covers were determined. There was no visual evidence of pitting or corrosion inside the ends of the heat exchanger. A radiochemical analysis of a smear sample taken from the inside of number one handhole showed the presence of the following isotopes- Fe/sup 59/, Co/ sup 58/, s1>s, and Zr/sup 95/. A radiation survey performed in four handholes indicated a maximum level of 1 r/hr. (W.L.H.)
Date: October 16, 1960
Partner: UNT Libraries Government Documents Department

The Russian-American Gallium solar neutrino Experiment

Description: The Russian-American Gallium solar neutrino Experiment (SAGE) is described. The solar neutrino flux measured by 31 extractions through October, 1993 is presented. The result of 69 {+-} 10{sub {minus}7}{sup +5} SNU is to be compared with a standard solar model prediction of 132 SNU. The status of a {sup 51}Cr neutrino source irradiation to test the overall operation of the experiment is also presented.
Date: December 31, 1995
Creator: Elliott, S.R.; Abdurashitov, J.N. & Bowles, T.J.
Partner: UNT Libraries Government Documents Department

Assessment of activation products in the Savannah River Site environment

Description: This document assesses the impact of radioactive activation products released from SRS facilities since the first reactor became operational late in 1953. The isotopes reported here are those whose release resulted in the highest dose to people living near SRS: {sup 32}P, {sup 51}Cr, {sup 60}C, and {sup 65}Zn. Release pathways, emission control features, and annual releases to the aqueous and atmospheric environments are discussed. No single incident has resulted in a major acute release of activation products to the environment. The releases were the result of normal operations of the reactors and separations facilities. Releases declined over the years as better controls were established and production was reduced. The overall radiological impact of SRS activation product atmospheric releases from 1954 through 1994 on the offsite maximally exposed individual can be characterized by a total dose of 0.76 mrem. During the same period, such an individual received a total dose of 14,400 mrem from non-SRS sources of ionizing radiation present in the environment. SRS activation product aqueous releases between 1954 and 1994 resulted in a total dose of 54 mrem to the offsite maximally exposed individual. The impact of SRS activation product releases on offsite populations also has been evaluated.
Date: July 1, 1996
Creator: Carlton, W.H. & Denham, M.
Partner: UNT Libraries Government Documents Department

Reactions of sigma-bonded organochromium(III)complexes

Description: Three projects were carried out, each dealing with the kinetics and mechanism of reactions of sigma-bonded organochromium(III) complexes of the form (H$sub 2$O)$sub 5$CrR$sup 2+$. Part I describes the kinetics of the reaction of dichloromethylchromium(III) ion with chromium(II) ion in aqueous acid. Part II deals with the radioexchange of 4-pyridinomethylchromium(III) ion with $sup 51$Cr$sup 2+$ and the kinetics of formation of the organochromium species at 55$sup 0$ in 1 M H$sup +$. Part III deals with the reactions of Hg$sup 2+$ and CH$sub 3$Hg$sup +$ with a series of (H$sub 2$O)$sub 5$CrR$sup 2+$ complexes, in which R is an aliphatic alkyl group, a haloalkyl group, or an aralkyl group. (LK)
Date: December 1, 1975
Creator: Leslie, J.P. II
Partner: UNT Libraries Government Documents Department

Refueling-Core I, Seed 1-Disassembly Inspection of Control Rod Drive Mechanisms. Test Results T-643711

Description: An inspection was made of the drive mechanisms for corrosion, crud, pitting, and activity. Localized crud deposits were found in the L-5, F-12, and H-4 damper guide cup washers. Corrosion and pitting appeared slight. The gamma radiation level of the components ranged from 1 to 1900 mr/hr. Smear samples of the components indicated relatively low activity levels-the highest being 140 mr/ hr, gamma . The gamma emission spectrum for each smear sample showed the composition of all samples to be identical from Fe/sup 59/, Co/sup 60/, Mn/sup 54/ , Cr/sup 51/, Hf/sup 181/, and Zr/sup 95/. T he specific activity was highest for Co/sup 60/ (1.90 x 1O/sup 7/ dpm/mg) and lowest for Zr/sup 95/ (2.20 x 10/sup 4/ dpm/mg). (B.O.G.)
Date: October 18, 1960
Partner: UNT Libraries Government Documents Department

A TRACER STUDY OF THE TRANSPORT OF CHROMIUM IN FLUORIDE FUEL SYSTEMS

Description: An experimental study was made of the mass transport of chromium in poly- thermal Inconel-fluoride fuel systems. The transport of chromium was followed by toe technique of adding radioactive Cr/sup 51/ to the system as either CrF/sub 2/ , in the salt or as elemental chromium in the solid phase. The rates of diffusion of chromium in Inconel at 600, 700, 800, and 900 deg C were determined by an electropolishing technique. Polythermal studies were carried out by three methods, tilting capsules, thermal-convection loops, and pumping loops. Tilting- capsule experiments indicated that the preferred location for chromium deposition on the wall was in the region of maximum temperature but the conclusions were not clear cut. Thermal convection loops operated for 125 and 288 hr showed radioactivity profile which could be attributed to simple exchange, with some distortion in the 288 hr case. The duration of these experiments was evidently insufficient io allow equilibrium to be reached in the salt. A thermal- convection loop operated for 400 hr showed distortion in the exchange radioactivity profile which indicated a favorable position for chromium deposition at a point about 100 deg F below the maximum wall temperature, and on the upstream side of the flow. A pumping loop of Inconel and salt mix gave an activity profile which was very similar to that of the 400-hr thermalconvection loop, indicating a favorable deposition point 100 deg F below maximuim temperature on the upstream side. One hypothesis advanced is that the long-term corrosion rate of chromium in the Inconel-salt system is controlled by the rate of diffusion of chromium into the wall at a temperature about 100 deg F below the maximum temperature on the upstream side. (auth)
Date: June 18, 1957
Creator: Price, R.B.; Sunderman, D.N.; Pobereskin, M. & Calkin, G.D.
Partner: UNT Libraries Government Documents Department

Interim report 2: Production test IP-581-A half-plant high flocculation pH test at B Reactor

Description: A half-plant high flocculation pH test began at B Reactor on September 24, 1963. The purpose of the test was to determine whether operation of the water plant flocculation basins and filters at a pH higher than 7.0 with subsequent coolant pH adjustment to 6.6 is beneficial as far as radioactivity in the effluent is concerned. It is planned to increase the flocculation basin pH in steps to a maximum of 7.6. Although primarily an effluent activity test, fuel discharged after a metal cycle at each water plant condition will be monitored by visual examination. Thus, it will be possible to determine whether the incidence of localized corrosion is influenced by the various modes of operation. One 20 column fuel discharge, ten columns from each side of the reactor, was obtained prior to the start of the test. This report discusses the results obtained from the first discharge of fuel under test conditions.
Date: February 11, 1963
Creator: Geier, R. G.
Partner: UNT Libraries Government Documents Department

Contamination control: Columbia River monthly report, January 1966

Description: It is the purpose of this report to present data obtained from the routine reactor effluent radioactivity monitoring program as well as the results obtained from the research and development program directed toward the reduction of effluent radioactivity. Samples of the effluent from each reactor are obtained each weekday during operation and analyzed for P{sup 32}, As{sup 76}, Np{sup 239}, and Cr{sup 51}.
Date: January 31, 1966
Creator: Geier, R. G.
Partner: UNT Libraries Government Documents Department

Production test IP-543-A effluent sampling -- overbore tube. Final report

Description: It had been postulated that the increased film area of a charged overbore tube would be counterbalanced by the lower temperature fuel surface and decreased flux so that the radioisotope content of the effluent would be the same as that from a normal tube. In order to confirm or deny the postulate, Tube 3267-C was equipped with an effluent sample line under the provisions of PT-IP-543-A. Sampling and analytical work began in mid-April and continued through November, 1963. Effluent samples obtained from an overbore tube at C Reactor over a nine-month period were analyzed for P{sup 32}, As{sup 76} Np{sup 239} and Cr{sup 51}. Based on the results obtained for these isotopes, it can be concluded that the radioisotope content of the effluent from an overbore tube will be the same as the radioisotope content of the effluent from a normal size tube operating under similar conditions.
Date: January 9, 1964
Creator: Geier, R. G.
Partner: UNT Libraries Government Documents Department

Human radiation studies: Remembering the early years: Oral history of cell biologist Don Francis Petersen, Ph.D., conducted November 29, 1994

Description: This report is a transcript of an interview of Dr. Don Francis Petersen by representatives of the US DOE Office of Human Radiation Experiments. Dr. Petersen was selected for this interview because of his long research career at Los Alamos and his knowledge of the Atomic Energy Commission`s biomedical program. Dr. Petersen did not personally conduct research on human subjects. After a brief biographical sketch Dr. Petersen discusses his remembrances of the early use of radionuclides as biological tracers, aspects of nuclear weapons testing in the 1940`s and 1950`s including fallout studies, the means by which research projects were approved, use of humans in the whole-body counter, and the Health Division Biomedical responsibilities.
Date: August 1, 1995
Partner: UNT Libraries Government Documents Department

Physiopathology of blood platelets and development of platelets substitutes. Progress report, August 1, 1976--October 31, 1977. [/sup 51/Cr]

Description: Progress is reported on the following research projects: the effect of estrogen on platelet aggregability and thrombus formation; the antithrombotic effect of platelet inhibiting agents in a bench model of artificial kidney; the arrest of hemorrhage in severely alloimmunized thrombocytopenic patients; and in vivo elution of /sup 51/Cr from labeled platelets induced by antibody. (HLW)
Date: July 31, 1977
Creator: Baldini, M G
Partner: UNT Libraries Government Documents Department