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ENVIRONMENTAL RADIOACTIVITY AT ARGONNE NATIONAL LABORATORY. Report for the Year 1959

Description: The results of the environmental monitoring program at Argonne National Laboratory for 1959 are given. The radioactive content of the environment was measured by performing radiochemical analyses and total activity measurements on several types of materials collected on the ANL site and from locations approximately 10, 25, and 100 miles from the Laboratory. The sampling locations are given in Part II. The average total activities in samples of water, material from the beds of lakes and streams (bottom silt), soil, and plants during 1959 are tabulated. For purposes of comparison, the results obtnined from 1952 through 1959 are included. Air-filter results are also tabulated. Fallout activity was present in most samples at all locations. The amount of fall-out was relatively high during the first part of the year, but decreased markedly during the latter half. By the end of the year the shorter-lived fission products from fall-out were at the lowest level since 1955. Airborne beta activity from fall-out decreased from a maximum of about 5 mu mu c/m/sup 3/ in April to less than 0.1 mu mu c/m/sup 3/ in December. The average for the year, about 2.3 mu mu c/m/sup 3/, was 25% less than for 1958, but approximately twice as high as the average from 1953 to 1957. The long-lived airborne alpha activity has not changed appreciably since 1953. Air-filter samples were collected both on the site and at four locations from 6 to 20 miles from the Laboratory. The activities were essentially the same both on and off the site, and no indication of activity originating at Argonne was found in the samples. (auth)
Date: January 1, 1961
Creator: Sedlet, J.
Partner: UNT Libraries Government Documents Department

Effect of physico-chemical properties on metabolism of transuranium oxide aerosols inhaled by beagle dogs

Description: The oxides of four transuranium isotopes ($sup 238$Pu, $sup 239$Pu, $sup 241$Am, and $sup 244$Cm), prepared by identical methods of calcining the oxalate at 750$sup 0$C for two hours, had different physico-chemical properties. For all four oxides the density ranges from 9.8 to 11.4 g cm$sup -3$ and initial ultrafilterability (suspended fraction of activity less than 24 A) varied from 0.002 percent for $sup 239$PuO$sub 2$ to 2.24 percent for $sup 238$PuO$sub 2$. Dogs were exposed by nose-only techniques to aerosols generated by nebulizing water suspensions of the oxides. The dogs were sacrificed at intervals from one week to about a year postexposure. The rate of translocation of material from lung to other tissues increased from $sup 239$Pu to $sup 238$Pu to $sup 241$Am to $sup 244$Cm, possibly reflecting the decrease in mean particle size from an MMD of 0.7 $mu$m to $sup 239$PuO$sub 2$ to 0.6 $mu$m for $sup 238$PuO$sub 2$ to 0.4 $mu$m for $sup 241$AmO$sub 2$ to 0.1 $mu$m for $sup 244$CmO/sub x/. Accumulation of the isotopes in the liver and skeleton as a percentage of final body burden was 1 percent $sup 239$Pu and 7 to 23 percent for $sup 238$Pu at about a year postexposure, while at 270 days postexposure, values were 40 percent for $sup 241$Am and 40 to 30 percent for $sup 244$Cm. (auth)
Date: January 1, 1975
Creator: Craig, D.K.; Park, J.F. & Ryan, J.L.
Partner: UNT Libraries Government Documents Department

Half-life of 14O

Description: We have measured the half-life of 14O, a superallowed (0+\rightarrow 0+) \beta decay isotope. The 14O was produced by the12C(3He,n)14O reaction using a carbon aerogel target. A low-energy ionbeam of 14O was mass separated and implanted in a thin beryllium foil.The beta particles were counted with plastic scintillator detectors. Wefind \tau 1/2 = 70.696 +- 0.037\sigma. This result is 2.0\sigma higherthan an average value from six earlier experiments, but agrees moreclosely with the most recent previous measurment.
Date: January 11, 2006
Creator: Burke, Jason T.; Vetter, Paul A.; Freedman, Stuart J.; Fujikawa,Brian K. & Winter, Wesley T.
Partner: UNT Libraries Government Documents Department

Nuclear Thermodynamics of the Heaviest Elements. II

Description: The masses of the isotopes of the heaviest elements have been calculated from known decay data in the region, extended by means of decay energies calculated from closed decay-energy cycles and estimated from the systematics of alpha and beta decay energies. The absolute values of the masses are based on the mass-spectrometrically determined mass of Pb{sup 208} and a few measured neutron binding energies. The half-life systematics of alpha decay and spontaneous fission are also presented, and some predictions of the properties of as yet undiscovered nuclides are made.
Date: January 1, 1958
Creator: Foreman Jr., Bruce M. & Seaborg, Glenn T.
Partner: UNT Libraries Government Documents Department

Nitrogen 12

Description: N{sup 12} is shown to have a half life of 12.5 {+-} 1 milliseconds, and a positron upper limit of 16.6 {+-} 0.2 Mev. It is produced by the reaction C{sup 12}(p,n)N{sup 12}, and has a threshold proton energy of 20.0 Mev. This indicates that N{sup 12} is within about 200 Kev of being unstable against proton emission. The mass of N{sup 12} is 12.0228 {+-} 0.00015, and the beta transition is allowed.
Date: January 19, 1949
Creator: Alvarez, Luis W.
Partner: UNT Libraries Government Documents Department

SEARCH FOR AN 80-ms SPONTANEOUS FISSION ACTIVITY IN BOMBARDMENTS OF 249Bk WITH 15N

Description: A rotating drum system was used to search for an 80-ms spontaneous fission (sf) activity in the reaction of {sup 15}N with {sup 249}Bk. No such activity was found beyond a cross section limit of 0.3 {+-} 0.3 nb. A sf activity with a half-life of about 20 ms and a formation cross section of 12 nb at 82 MeV was observed. The identity of this activity has not been determined.
Date: January 1, 1980
Creator: Nitschke, J.M.; Fowler, M.; Ghiorso, A.; Leber, R.E.; Nurmia, M.J.; Somerville, L.P. et al.
Partner: UNT Libraries Government Documents Department

MOUND LABORATORY PROGRESS REPORT FOR JANUARY 1961

Description: Work was begun to determine the physical properties of mica-filled diallyl phthalate. Both the impact and tensile strength values compared favorably wlth asbestos-filled DAP formulatlons. The tensile values compared with the upper limit tensile strength values for asbestos-filled formulations. Adiprene-ferric acetyl acetonate-polyol systems were developed as adhesives and their properties studied. Sources of kilogram quantities of Th/sup 2//sup 3//sup 0/ were investigated. The samples were analyzed by a direct CeF/sub 3/ precipitation procedurc or by a tributyl phosphate-cerium procedure. The half- life of Ra/sup 2//sup 2//sup 3/ was found to be 11.3700 plus or minus 0.0065 days. Differential thermal analyses were made of lanthanum and praseodymium metals. Three preilminary determinations of the density of molten cerium were made by the vacuum pycnometer method. An average value of 6.58 was obtained. Leaching tests in water and in 0.1N HCl were continued on fibers of an experimental glass containing 10 wt.%n plutonium oxide. (M.C.G.)
Date: January 31, 1961
Creator: Eichelberger, J.F.
Partner: UNT Libraries Government Documents Department

243Am + 48Ca: A Second Look at the Rf/Db Data Set

Description: In December of 2005 a series of experiments were performed at the U400 Cyclotron at the Flerov Laboratory of Nuclear Reactions in Dubna, Russia, using the reaction {sup 243}Am ({sup 48}Ca,3n) {sup 288}115 which, after a sequence of five alpha decays, produces a long-lived ({approx}1d) fission activity that had been detected previously in experiments using the Dubna Gas Filled Recoil Separator (DGFRS). These experiments were attempts to establish the elemental identity of the fissioning species as dubnium (element 105), which in turn confirms the identity of the original parent nucleus as element 115 through genetic correlation of the subsequent alpha decays. A series of approximately 24-hour bombardments were followed by chemical separations designed to isolate the Group Four and Five chemical fractions, and then separate the Nb and Ta fractions, which are Group Five homologues of dubnium and should therefore behave chemically similar. The samples were prepared for alpha and fission measurement and counted for an extended period of time. Fission events were detected in the Ta-like fractions only, which correspond to the fission coming from either the {sup 268}Db isotope directly or long-lived electron-capture decay in {sup 268}Db followed by a short half-life fission of {sup 268}Rf. In May of 2007 the Rf and Db fractions were recounted for very long times on alpha spectrometers to look at what species remained after approximately 1.5 years of time. One of the issues to be resolved was the potential for actinide contamination of the counting samples, which might have adverse affects on the observed data from the original experiment. In the original experiment the samples had significant quantities of {beta}-{gamma} activity which made the absolute identification of the alpha activity in each sample difficult. By allowing the {beta}-{gamma} activity to decay away, it gives us the opportunity to make definitive identifications ...
Date: January 29, 2008
Creator: Henderson, R A & Moody, K J
Partner: UNT Libraries Government Documents Department

Neutron Deficient Isotopes of Tellurium and Antimony

Description: While investigating the relative yields for the many reactions resulting from the irradiation of antimony with 200-Mev deuterons in the Berkeley 184-inch cyclotron several previously unreported isotopes of tellurium and antimony were encountered. The tellurium fraction when followed on a thin mica window counter could be resolved into half-life periods of 2.5 hrs, 6.0 days and a small amount of a long-lived component. The 2.5 hour period has not been further characterized with respect to mass number or mode of decay other than to note that the radiation is predominantly electrons. The 6.0-day period is accompanied by positrons which were shown to be due to a 3.5 minute antimony daughter which is undoubtedly the same activity assigned to Sb{sup 118} by Risser, Lark-Horowitz and Smith. The positron energy was found to be 3.1 {+-} 0.2 Mev by absorption in berylllum and from the end point of the energy distribution curve taken with a low-resolution beta-ray spectrometer. Gamma activity is also present with this period. The 6.0-day tellurium showed a high abundance of x-rays, little or no conversion electrons and some gamma-ray activity which could be due to the 3.5 minute antimony daughter. The tellurium fraction contained another component of 4.5-day half-life which could not be observed in the decay curve because of its low abundance but which was detected by means of its 39-hour antimony daughter. The 39-hour antimony showed x-rays of tin (critical absorption with cadmiium, silver and palladium), no detectable hard radiation or electrons and is apparently identical with an activity recently assigned to Sb{sup 119} by Coleman and Pool.
Date: January 1, 1948
Creator: Lindner, M. & Perlman, I.
Partner: UNT Libraries Government Documents Department

The Metabolism of Curium in the RAT

Description: The heaviest of the known elements is curium, which was recently discovered by Seaborg and his associates. This new element can be produced by the alpha particle transmutation of plutonium by the following reaction: {sub 94}Pu{sup 239} + {sub 2}He{sup 4} {yields} {sub 96}Cm{sup 242} + {sub 0}N{sup 1} This isotope of curium is radioactive and decays by the emission of an alpha particle to form plutonium 238 which, in turn, is also radioactive. Curium 242 has a half-life of 150 days, and its radioactive daughter, plutonium 238, has a half-life of 50 years. This isotope of plutonium decays by the emission of an alpha particle to form uranium 234 which has a half-life of 233,000 years. Shortly after the organization of the Atomic Energy Project, it became apparent that formidable problems would be presented as the result of the release of nuclear energy. One of the most urgent of these was the hazard presented by the production of large quantities of the radio-elements created by the fission of uranium and the coincidental formation of neptunium and plutonium. In an attempt to evaluate the potential danger presented by these radio-elements from the chain reacting pile, a large series of metabolic studies with experimental animals were undertaken in a number of laboratories working upon the Atomic Energy program. These studies, which have been briefly summarized elsewhere, included a series of investigations on the metabolism in the rat of the more important members of the fission products in the carrier-free state, as well as most of the heaviest elements at the end of the periodic table. These studies made it possible to predict on a semi-quantitative basis the potential hazards that this large number of radioactive elements might present should they gain entry into the body.
Date: January 15, 1948
Creator: Hamilton, J.; Scott, K. & Axelrod, D.
Partner: UNT Libraries Government Documents Department

Lunar surface outgassing and alpha particle measurements

Description: The Lunar Prospector Alpha Particle Spectrometer (LP APS) searched for lunar surface gas release events and mapped their distribution by detecting alpha particle?; produced by the decay of gaseous radon-222 (5.5 MeV, 3.8 day half-life), solid polonium-2 18 (6.0 MeV, 3 minute half-life), and solid polonium-210 (5.3 MeV, 138 day half-life, but held up in production by the 21 year half-life of lead-210). These three nuclides are radioactive daughters from the decay of uranium-238.
Date: January 1, 2002
Creator: Lawson, S. L. (Stefanie L.); Feldman, W. C. (William C.); Lawrence, David J. (David Jeffery),; Moore, K. R. (Kurt R.); Elphic, R. C. (Richard C.); Maurice, S. (Sylvestre) et al.
Partner: UNT Libraries Government Documents Department

EFFECTIVE DOSIMETRIC HALF LIFE OF CESIUM 137 SOIL CONTAMINATION

Description: In the early 1960s, an area of privately-owned swamp adjacent to the US Department of Energy's Savannah River Site (SRS), known as Creek Plantation, was contaminated by site operations. Studies conducted in 1974 estimated that approximately 925 GBq of {sup 137}Cs was deposited in the swamp. Subsequently, a series of surveys--composed of 52 monitoring locations--was initiated to characterize and trend the contaminated environment. The annual, potential, maximum doses to a hypothetical hunter were estimated by conservatively using the maximum {sup 137}Cs concentrations measured in the soil. The purpose of this report is to calculate an 'effective dosimetric' half-life for {sup 137}Cs in soil (based on the maximum concentrations) and compare it to the effective environmental half-life (based on the geometric mean concentrations).
Date: January 9, 2008
Creator: Jannik, T; P Fledderman, P & Michael Paller, M
Partner: UNT Libraries Government Documents Department

Neptunium (VI) and neptunium (VI/V) mixed valence cluster compounds

Description: Neptunium has three readily accessible oxidation states, IV, V and VI, which can coexist under certain conditions, with the aqueous soluble neptunyl(V) moiety, {l_brace}NpO{sub 2}{r_brace}{sup +}, of most environmental relevance. Careful control of Np chemistry is required during actinide separation processes. In addition, the long half life of the major alpha emitting isotope ({sup 237}Np, t{sub 1/2} = 2.144 x 10{sup 6} years) renders Np a major contributor to the radiotoxicity of nuclear waste as a function of time. Significant quantities of neptunium are generated in nuclear reactors and the current surge in interest in nuclear power will lead to an increase in our need to further understand the chemistry of this element. It is clearly of importance that Np chemistry is well understood and there have been several recent investigations into the structural, spectroscopic and magnetic properties of Np compounds. However, the vast majority of this chemistry has been performed in aqueous solution, prohibiting the use of air and moisture sensitive ligands. This is in stark contrast to uranium and thorium where inert atmosphere chemistry with moisture sensitive donor ligands has flourished, yielding greater insight into the structural and electronic properties of these early actinides. For the uranyl(VI) moiety, {l_brace}UO{sub 2}{r_brace}{sup 2+}, UO{sub 2}Cl{sub 2}(thf){sub 3} (and the desolvated dimer [UO{sub 2}Cl{sub 2}(thf)]{sub 2}) have proven to be excellent moisture-free reagents for inert atmosphere uranyl chemistry. These starting reagents have been used extensively within our group to study soft donor ligand coordination in the uranyl equatorial plane and oxo-activation to Lewis acid coordination. However, until now the absence of such a starting reagent for Np has limited our ability to extend this chemistry any further across the actinide series, which is required if we are to gain a more complete understanding of 5f element chemistry. The synthesis of [Np{sup ...
Date: January 1, 2008
Creator: May, Iain
Partner: UNT Libraries Government Documents Department

Nuclear Reactions of Arsenic with 190 Mev Deuterons

Description: Isotopes formed in the bombardment of {sub 33}As{sup 75} with 190 Mev deuterons range in atomic number up to 24 (or more) mass units lighter than As{sup 75}. Identification of these isotopes was based on chemical behavior and half-life determination. Relative yields have been calculated and show that 80% of the observed reactions produce isotopes within 8 mass units of As{sup 75}. Three new isotopes have been observed: 9.5 d. Se{sup 72} (K), 44 m, Se{sup 71} ({beta}{sup +}), and 52 m, As{sup 71} ({beta}{sup +}).
Date: January 21, 1948
Creator: Hopkins Jr, H.H. & Cunningham, B.B.
Partner: UNT Libraries Government Documents Department

ADPF spoke cavity cryomodule concept

Description: The Accelerator Driven Test Facility (ADTF) is being developed as a reactor concepts test bed for transmutation of nuclear waste. A 13.3 mA continuous-wave (CW) proton beam will be accelerated to 600 MeV and impinged on a spallation target. The subsequent neutron shower is used to create a nuclear reaction within a subcritical assembly of waste material that reduces the waste half-life from the order of 10{sup 5} years to 10{sup 2} years. Additionally, significant energy is produced that can be used to generate electrical power. The ADTF proton accelerator consists of room-temperature (RT) structures that accelerate the beam to 6.7-MeV and superconducting (SC) elements that boost the beam's energy to 600-MeV. Traditional SC elliptical cavities experience structural difficulties at low energies due to their geometry. Therefore, stiff-structured SC spoke cavities have been adopted for the energy range between 6.7 and 109 MeV. Elliptical cavities are used at the higher energies. This paper describes a multi-spoke-cavity cryomodule concept for ADTF.
Date: January 1, 2001
Creator: Kelley, J. P. (John Patrick); Roybal, P. L. (Phillip L.); La Fave, R. P. (Richard P.); Waynert, J. A. (Joseph A.); Schrage, D. L. (Dale L.); Schmierer, E. N. (Eric N.) et al.
Partner: UNT Libraries Government Documents Department