WorldWideScience

Sample records for carbon 12 decay radioisotopes

  1. Power from Radioisotopes (Rev.)

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R; Mead, Robert L

    1971-01-01

    This booklet discusses Systems for Nuclear Auxiliary Power (SNAP), called isotope power generators, that are based on using heat from the decay of radioisotopes to produce electricity. These are the SNAP systems with odd-numbered designators. The basics of radioisotope thermoelectric generators (RTGs) are discussed and their uses as power sources in space exploration and on earth are described. Various radioisotope heat sources are discussed and a table of RTGs built under the SNAP program listing their uses, electrical power, weight, the radioisotope used, the radioisotope's half-life, and the generator life is given.

  2. Development and characterization of carbon-bonded carbon fiber insulation for radioisotope space power systems

    Energy Technology Data Exchange (ETDEWEB)

    Wei, G.C.; Robbins, J.M.

    1985-06-01

    The General-Purpose Heat Source (GPHS), an improved radioisotope heat source, employs a unique thermal insulation material, carbon-bonded carbon fiber (CBCF), to protect the fuel capsule and to help achieve the highest possible specific power. The CBCF insulation is made from chopped rayon fiber about 10 ..mu..m in diameter and 250 ..mu..m long, which is carbonized and bonded with phenolic resin particles. The CBCF shapes, both tubes and plates, are formed in a multiple molding facility by vacuum molding a water slurry of the carbonized chopped-rayon fiber (54 wt %) and phenolic resin (46 wt %). The molded shapes are subsequently dried and cured. Final carbonization of the resin is at 1600/sup 0/C. Machining to close tolerances (+-0.08 mm) is accomplished by conventional tooling and fixturing. The resulting material is an excellent lightweight insulation with a nominal density of 0.2 Mg/m/sup 3/ and a thermal conductivity of 0.24 W(m.K) in vacuum at 2000/sup 0/C. Several attributes that make CBCF superior to other known high-temperature insulation materials for the GPHS application have been identified. It has the excellent attributes of light weight, low thermal conductivity, chemical compatibility, and high-temperature capabilities. The mechanical strength of CBCF insulation is satisfactory for the GPHS application; it has passed vibration tests simulating launch conditions. The basic fabrication technique was refined to eliminate undesirable large pores and cracks often present in materials fabricated by earlier techniques. Also, processing was scaled up to incease the fabrication rate by a factor of 10. The specific properties of the CBCF were tailored by adjusting material and processing variables to obtain the desired results. We report here how work on CBCF characterization and development conducted at ORNL from 1978 through 1980 has contributed to the GPHS program to meet the requirements of both the Galileo and Ulysees Missions.

  3. High efficiency direct thermal to electric energy conversion from radioisotope decay using selective emitters and spectrally tuned solar cells

    Science.gov (United States)

    Chubb, Donald L.; Flood, Dennis J.; Lowe, Roland A.

    1993-01-01

    Thermophotovoltaic (TPV) systems are attractive possibilities for direct thermal-to-electric energy conversion, but have typically required the use of black body radiators operating at high temperatures. Recent advances in both the understanding and performance of solid rare-earth oxide selective emitters make possible the use of TPV at temperatures as low as 1200K. Both selective emitter and filter system TPV systems are feasible. However, requirements on the filter system are severe in order to attain high efficiency. A thin-film of a rare-earth oxide is one method for producing an efficient, rugged selective emitter. An efficiency of 0.14 and power density of 9.2 W/KG at 1200K is calculated for a hypothetical thin-film neodymia (Nd2O3) selective emitter TPV system that uses radioisotope decay as the thermal energy source.

  4. Atomic Radiations in the Decay of Medical Radioisotopes: A Physics Perspective

    Directory of Open Access Journals (Sweden)

    B. Q. Lee

    2012-01-01

    Full Text Available Auger electrons emitted in nuclear decay offer a unique tool to treat cancer cells at the scale of a DNA molecule. Over the last forty years many aspects of this promising research goal have been explored, however it is still not in the phase of serious clinical trials. In this paper, we review the physical processes of Auger emission in nuclear decay and present a new model being developed to evaluate the energy spectrum of Auger electrons, and hence overcome the limitations of existing computations.

  5. Radioisotope instruments

    CERN Document Server

    Cameron, J F; Silverleaf, D J

    1971-01-01

    International Series of Monographs in Nuclear Energy, Volume 107: Radioisotope Instruments, Part 1 focuses on the design and applications of instruments based on the radiation released by radioactive substances. The book first offers information on the physical basis of radioisotope instruments; technical and economic advantages of radioisotope instruments; and radiation hazard. The manuscript then discusses commercial radioisotope instruments, including radiation sources and detectors, computing and control units, and measuring heads. The text describes the applications of radioisotop

  6. Accelerated Decay of Radioisotopes

    Science.gov (United States)

    2013-01-01

    Designing of PFRP experiments for controlled ionic species, analyzing results of recent neutron source development experiments, calculating expected...controllable and varied to access reactions of interest (primarily (n,n’) inelastic scattering). Theory and analysis using Monte Carlo codes ( MCNPX ) is still...MlTL flow theory, circuit calculation to determine the Mercury load line, neutron yield calculations , and LSP simulations. Experimentally, the total

  7. News on C-12 from beta-decay studies

    NARCIS (Netherlands)

    Fynbo, HOU; Diget, CA; Prezado, Y; Aysto, J; Bergmann, UC; Cederkall, J; Dendooven, P; Fraile, LM; Franchoo, S; Fulton, BR; Huang, W; Huikari, J; Jeppesen, H; Jokinen, A; Jonson, B; Jones, P; Koster, U; Meister, M; Nilsson, T; Nyman, G; Borge, MJG; Riisager, K; Rinta-Antila, S; Vogelius, IS; Tengblad, O; Turrion, M; Wang, Y; Weissman, L; Wilhelmsen, K

    2004-01-01

    We discuss the importance of the spectroscopic properties of the resonances of C-12 just above the 3alpha-threshold, and review the existing experimental information of this region with emphasis on 0(+) and 2(+) states. A new experimental approach for studying the beta-decays of B-12 and N-12 is pre

  8. Estimation of groundwater residence time using environmental radioisotopes (14C,T) in carbonate aquifers, southern Poland.

    Science.gov (United States)

    Samborska, Katarzyna; Różkowski, Andrzej; Małoszewski, Piotr

    2013-01-01

    Triassic carbonate aquifers in the Upper Silesia region, affected by intense withdrawal, have been investigated by means of isotopic analyses of (14)C, δ(13)C, δ(2)H, δ(18)O and (3)H. The isotopic examinations were carried out in the 1970s and in the early 1980s, and it was the first application of tracers to estimate age and vulnerability for the contamination of groundwater in this region. Similar isotopic analyses were conducted in 2007 and 2008 with the same Triassic carbonate formation. The isotopic examinations were performed within the confined part of the carbonate formation, wherein aquifers are covered by semi-permeable deposits. The direct recharge of the aquifer occurs in the outcrop areas, but it mainly takes place due to percolation of the water through aquitards and erosional windows. The Triassic aquifer has been intensively drained by wells and by lead-zinc mines. Nowadays, the declining water demand and closure of some mines have induced a significant increase in the water table level. The detailed analysis of the results, including the radiocarbon age corrections and the comparison of radioisotope activities, has made it possible to estimate the range of residence time within the carbonate Triassic aquifer. This range from several tens to several tens of thousands indicates that the recharge of aquifers might have occurred between modern times and the Pleistocene. The apparent age of the water estimated on the basis of (14)C activity was corrected considering the carbon isotope exchange and the diffusion between mobile water in fractures and stagnant water in micropores. The obtained corrected period of recharge corresponds to the result of investigations of noble gases, which were carried out in the 1990s. In almost half of the cases, groundwater is a mixture of young and old water. The mixing processes occur mainly in areas of heavy exploitation of the aquifer.

  9. Study of the ${\\beta}$-decay of $^{12}$B

    CERN Multimedia

    2002-01-01

    We propose to study the ${\\beta}$-decay of $^{12}$B with a modern segmented Si-detector array to get new and much improved information on states in $^{12}$C above the ${\\alpha}$-threshold. These states mainly decay into final states of three ${\\alpha}$-particles and their study therefore is a challenge for nuclear spectroscopy. The properties of these states is of high current interest for nuclear astrophysics and for the nuclear many-body problem in general. We ask for a total of 15 shifts.

  10. Decay of cacti and carbon cycling

    Science.gov (United States)

    Garvie, Laurence A. J.

    2006-03-01

    Cacti contain large quantities of Ca-oxalate biominerals, with C derived from atmospheric CO2. Their death releases these biominerals into the environment, which subsequently transform to calcite via a monohydrocalcite intermediate. Here, the fate of Ca-oxalates released by plants in arid environments is investigated. This novel and widespread form of biomineralization has unexpected consequences on C cycling and calcite accumulation in areas with large numbers of cacti. The magnitude of this mineralization is revealed by studying the large columnar cactus Carnegiea gigantea (Engelm.) Britton and Rose in southwestern Arizona (locally called the saguaro). A large C. gigantea contains on the order of 1×105 g of the Ca-oxalate weddellite—CaC2O4·2H2O. In areas with high C. gigantea density, there is an estimated 40 g Catm m-2 sequestered in Ca-oxalates. Following the death of the plant, the weddellite transforms to calcite on the order to 10-20 years. In areas with high saguaro density, there is an estimated release of up to 2.4 g calcite m-2 year-1 onto the desert soil. Similar transformation mechanisms occur with the Ca-oxalates that are abundant in the majority of cacti. Thus, the total atmospheric C returned to the soil of areas with a high number density of cacti is large, suggesting that there may be a significant long-term accumulation of atmospheric C in these soils derived from Ca-oxalate biominerals. These findings demonstrate that plant decay in arid environments may have locally significant impacts on the Ca and inorganic C cycles.

  11. Investigation of the excitation functions for some medical radioisotopes production

    Science.gov (United States)

    Kılınç, Fatma; Karpuz, Nurdan; Çetin, Betül

    2016-11-01

    One of the main application fields of nuclear technology is medicine and radioisotopes are used in medicine. Production of those radioisotopes is important and in the production processes the cross section must be known. All the production of radioisotope used in medicine is based on the nuclear reactions means they are not natural. The decay time of produced radioisotopes is important as from production to hospital can take time and thus generally generator is used to produce some radioisotopes. Radioisotopes are widely produced in reactors or cyclotron type accelerator. Type of radioisotopes direct way to be used in production processes. Thus obtaining of cross section becomes crucial. For this purposes the theoretical calculation cross section of some radioisotopes used in medicine will be calculated in this study. The calculations will be done using Monte Carlo code of TALYS 1.6

  12. The 12C* Hoyle state in the inelastic 12C + 12C reaction and in 24Mg* decay

    Science.gov (United States)

    Morelli, L.; Bruno, M.; D'Agostino, M.; Baiocco, G.; Gulminelli, F.; Abbondanno, U.; Barlini, S.; Bini, M.; Casini, G.; Cinausero, M.; Degerlier, M.; Fabris, D.; Gramegna, F.; Mabiala, J.; Marchi, T.; Olmi, A.; Pasquali, G.; Piantelli, S.; Valdré, S.

    2016-08-01

    The reaction 12C + 12C at 95 MeV has been studied at the Legnaro Laboratories of INFN with the GARFIELD + RCo apparatus. Data have been analyzed in order to investigate the decay of the Hoyle state of 12C*. Two different data selections have been made. The first one corresponds to peripheral binary collisions where the quasi-projectile is excited to the Hoyle state and the target has been left in the ground state. The second selection allows for studying central events with the formation of a 24Mg* and the Hoyle state is obtained as a step of the decay chain. The characteristics of the Hoyle state decay are very similar in the two samples and point to a mainly sequential decay through the population of an intermediate 8Begs, with a small contribution (˜1.1%) from simultaneous three α-particle processes.

  13. Exotic decay in Ba isotopes via 12C emission

    Indian Academy of Sciences (India)

    K P Santhosh; Antony Joseph

    2000-09-01

    Considering Coulomb and proximity potentials as barriers, we have calculated the half lives for 12C emission from various Ba isotopes using different mass tables. The half life for 112Ba isotope calculated by us is 6.020 × 103 s which is comparable with the experimental value 5.620 × 103 s. From our study it is found that 114Ba is the good parent for 12C emission whose emission rate is favorable for measurement. The half lives predicted by us lie very close to those reported by Shanmugam et al using their cubic plus Yukawa plus exponential model. It is observed that inclusion of proximity potential does not produce significant deviation from the linear nature of the Geiger–Nuttall plots. Also it is found that the neutron excess in the parent nuclei slows down the exotic decay process.

  14. Feasibility Study of a Three-Stage Radioisotope-Powered Mars Ascent Vehicle

    Science.gov (United States)

    Chalpek, T. M.; Allen, R. E.; Guan, J. Y.; Rao, S. S.; Howe, S. D.

    Recent advancements in methods of housing radioisotopes at the Center for Space Nuclear Research have led to the concept of a radioisotope thermal rocket--a rocket powered by the accumulated heat of radioisotope decay. Heat energy from the decay can be accumulated over long periods of time in a material of high heat capacity to create a thermal capacitor. The capacitor can then be discharged at such a rate as to provide high power for short periods of time; in this case, the heat is transferred to a gas propellant. This paper explores the feasibility of using a radioisotope thermal rocket with in-situ atmospheric CO2 propellant to deliver a 10 kg payload from the Martian surface to a 200 km circular orbit about Mars. Models of heat transfer, gas dynamics, and ascent mechanics are constructed to test performance of different core materials and geometries. Of the configurations tested, the best simulation results fail to meet the altitude and velocity requirements by 12 km and 50 m/s respectively. The proximity to success indicates that the given models are capable of reaching orbital parameters if optimization algorithms and closed-loop guidance methods are employed. It is believed, however, that the current models underestimate expansion losses to the degree that if more realistic and computationally-intensive models are incorporated, the effect will definitively disprove the concept with currently available technology. Based on this preliminary research, radioisotope thermal rockets utilizing current technology are not capable of serving as Mars ascent vehicles.

  15. Nonmesonic Hyperon Weak Decay Spectra in $^{12}_{\\Lambda}$C}

    CERN Document Server

    Gonzalez, I; Duarte, S; Krmpotić, F; Hussein, M S; Barbero, C

    2012-01-01

    We study the nonmesonic weak decay (NMWD) $\\Lambda N \\to nN$ of the ${}^{12}_{\\Lambda} C$ hypernucleus induced by the nucleon $N=n,p$ with transition rate $\\Gamma_N$. The nuclear process is described by the interplay of two models; one describing the NMWD of hyperon $\\Lambda$ in the nuclear environment, and the other taking into account the Final State Interaction (FSI) of the two outgoing nucleons with the residual nucleus. The first one is done in the framework of the Independent-Particle Shell-Model (IPSM), with the decay dynamics represented by the exchange of $\\pi+ \\eta+ K+\\rho+\\omega+K^*$ mesons with usual parametrization. For the second one is used a time dependent multicollisional intranuclear cascade schema (implemented in the CRISP code - Collaboration Rio-S\\~ao Paulo). The results obtained for inclusive and exclusive kinetic energy spectra, and the angular correlation are compared with recent data from KEK and FINUDA experiments. The calculated ratio $(\\Gamma_n / \\Gamma_p)^{\\partial{\\tiny FSI}}$, b...

  16. Linking fungal communities to wood density loss after 12 years of log decay.

    Science.gov (United States)

    Kubartová, Ariana; Ottosson, Elisabet; Stenlid, Jan

    2015-05-01

    Changes in biodiversity might alter decomposition processes and, consequently, carbon and nutrient cycling. We examined fungal diversity and density loss in experimental Norway spruce logs after 12 years of decay in a hemiboreal forest. Between 28 and 50% of the original wood biomass remained, depending on the fungal community composition in the log, operational taxonomic unit (OTU) richness had only a minor effect on the log biomass. Although the communities were OTU rich (190-340 OTUs per log), the majority of OTUs were infrequent or rare; wood degradation therefore depended mostly on the most abundant OTUs and their decomposing abilities. The least decayed logs were characterized by continuous dominance of an earlier colonizer and by high within-log community diversity, which was significantly related to sample variables (position in log, density and moisture). In the most decayed logs, the earlier colonizers were generally replaced by white-rot species able to exploit the highly decomposed wood. The communities were relatively spatially uniform within whole logs, independent of the sample variables, whereas among-log diversity was high. Importance of fungal community composition in decomposition processes should be taken into account when studying and modeling carbon dynamics in forest ecosystems.

  17. Radioisotope Power Supply Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Between 1998 and 2003, Hi-Z Technology developed and built a 40 mW radioisotope power supply (RPS) that used a 1 watt radioisotope heater unit (RHU) as the energy...

  18. Precise Branching Ratios to Unbound 12C States from 12N and 12B (beta)-Decays

    Energy Technology Data Exchange (ETDEWEB)

    Hyldegaard, S; Forssen, C; Alcorta, M; Barker, F C; Bastin, B; Borge, M G; Boutami, R; Brandenburg, S; Buscher, J; Dendooven, P; Diget, C A; Van Duppen, P; Eronen, T; Fox, S; Fulton, B R; Fynbo, H U; Huikari, J; Huyse, M; Jeppesen, H B; Jokinen, A; Jonson, B; Jungmann, K; Kankainen, A; Kirsebom, O; Madurga, M; Moore, I; Navratil, P; Nilsson, T; Nyman, G; Onderwater, G G; Penttila, H; Perajarvi, K; Raabe, R; Riisager, K; Rinta-Antila, S; Rogachevskiy, A; Saastamoinen, A; Sohani, M; Tengblad, O; Traykov, E; Vary, J P; Wang, Y; Wilhelmsen, K; Wilschut, H W; Aysto, J

    2008-08-20

    Two complementary experimental techniques have been used to extract precise branching ratios to unbound states in {sup 12}C from {sup 12}N and {sup 12}B {beta}-decays. In the first the three {alpha}-particles emitted after {beta}-decay are measured in coincidence in separate detectors, while in the second method {sup 12}N and {sup 12}B are implanted in a detector and the summed energy of the three {alpha}-particles is measured directly. For the narrow states at 7.654 MeV (0{sup +}) and 12.71 MeV (1{sup +}) the resulting branching ratios are both smaller than previous measurements by a factor of {approx_equal} 2. The experimental results are compared to no-core shell model calculations with realistic interactions from chiral perturbation theory, and inclusion of three-nucleon forces is found to give improved agreement.

  19. Radioisotope detection with accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Mast, T.S.; Muller, R.A.; Tans, P.P.

    1979-12-01

    High energy mass spectrometry is a new and very sensitive technique of measuring rare radioisotopes. This paper describes the techniques used to select and identify the individual radioisotope atoms in a sample and the status of the radioisotope measurements and their applications.

  20. Diffusion of Implanted Radioisotopes in Solids

    CERN Multimedia

    2002-01-01

    Implantation of radioisotopes into metal and semiconductor samples is performed. The implanted isotope or its decay-product should have a half-life long enough for radiotracer diffusion experiments. Such radioisotopes are utilized to investigate basic diffusion properties in semiconductors and metals and to improve our understanding of the atomic mechanisms of diffusion. For suitably chosen systems the combination of on-line production and clean implantation of radioisotopes at the ISOLDE facility opens new possibilities for diffusion studies in solids. \\\\ \\\\ The investigations are concentrated on diffusion studies of $^{195}$Au in amorphous materials. The isotope $^{195}$Au was obtained from the mass 195 of the mercury beam. $^{195}$Hg decays into $^{195}$Au which is a very convenient isotope for diffusion experiments. \\\\ \\\\ It was found that $^{195}$Au is a slow diffusor in amorphous Co-Zr alloys, whereas Co is a fast diffusor in the same matrix. The ``asymmetry'' in the diffusion behaviour is of considerab...

  1. Radioisotope production in Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Wan Anuar Wan Awang [Medical Technology Div., Malaysian Inst. for Nuclear Technology Research (MINT) (Malaysia)

    1998-10-01

    Production of Mo-99 by neutron activation of Mo-99 in Malaysia began as early as 1984. Regular supply of the Tc-99m extracted from it to the hospitals began in early 1988 after going through formal registration with the Malaysian Ministry of Health. Initially, the weekly demand was about 1.2 Ci of Mo-99 which catered the needs of 3 nuclear medicine centres. Sensitive to the increasing demand of Tc-99m, we have producing our own Tc-99m generator from imported TeO{sub 2} because irradiation TeO{sub 2} with our reactor give low yield of I-131. We have established the production of radioisotope for industrial use. By next year, Sm-153 EDTMP will be produce after we have license from our competent authority. (author)

  2. Production and utilization of radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Sekine, Toshiaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Matsuoka, Hiromitsu

    1999-03-01

    A plan of developing radioisotopes with a high power proton accelerator of the Neutron Science Project is presented. The status of production and utilization of radioisotopes in Japan is briefly discussed. The radioisotopes to be produced for biomedical use are discussed together with the facility for production of those radioisotopes and for research with the products. (author)

  3. Non-statistical decay and α-correlations in the 12C+12C fusion-evaporation reaction at 95 MeV

    Science.gov (United States)

    Morelli, L.; Baiocco, G.; D'Agostino, M.; Gulminelli, F.; Bruno, M.; Abbondanno, U.; Appannababu, S.; Barlini, S.; Bini, M.; Casini, G.; Cinausero, M.; Degerlier, M.; Fabris, D.; Gelli, N.; Gramegna, F.; Kravchuk, V. L.; Marchi, T.; Olmi, A.; Pasquali, G.; Piantelli, S.; Valdré, S.; Raduta, Ad R.

    2014-07-01

    Multiple alpha coincidences and correlations are studied in the reaction 12C+12C at 95 MeV for fusion-evaporation events completely detected in charge. Two specific channels with carbon and oxygen residues in coincidence with α -particles are addressed, which are associated with anomalously high branching ratios with respect to the predictions of Hauser-Feshbach calculations. Triple alpha emission appears kinematically compatible with a sequential emission from a highly excited Mg. The phase space distribution of α - α coincidences suggests a correlated emission from a Mg compound, leaving an oxygen residue excited above the threshold for neutron decay. These observations indicate a preferential α emission of 24Mg at excitation energies well above the threshold for 6 - α decay.

  4. Non-statistical decay and $\\alpha$-correlations in the $^{12}$C+$^{12}$C fusion-evaporation reaction at 95 MeV

    CERN Document Server

    Morelli, L; D'Agostino, M; Gulminelli, F; Bruno, M; Abbondanno, U; Appannababu, S; Barlini, S; Bini, M; Casini, G; Cinausero, M; Degerlier, M; Fabris, D; Gelli, N; Gramegna, F; Kravchuk, V L; Marchi, T; Pasquali, G; Piantelli, S; Valdré, S; Raduta, Ad R

    2014-01-01

    Multiple alpha coincidence and correlations are studied in the reaction $^{12}$C+$^{12}$C at 95 MeV for fusion-evaporation events completely detected in charge. Two specific channels with Carbon and Oxygen residues in coincidence with $\\alpha$-particles are addressed, which are associated with anomalously high branching ratios with respect the predictions by Hauser-Feshbach calculations. Triple alpha emission appears kinematically compatible with a sequential emission from a highly excited Mg. The phase space distribution of $\\alpha$-$\\alpha$ coincidences suggests a correlated emission from a Mg compound, leaving an Oxygen residue excited above the threshold for neutron decay. These observations indicate a preferential $\\alpha$ emission of $^{24}$Mg at excitation energies well above the threshold for $6-\\alpha$ decay.

  5. Economical Radioisotope Power Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Almost all robotic space exploration missions and all Apollo missions to the moon used Radioisotopic Thermoelectric Generators (RTGs) to provide electrical power to...

  6. RPA puzzle in ${^{12}C}$ weak decay processes

    CERN Document Server

    Krmpotic, F; Samana, A

    2002-01-01

    We explain the origin of the difficulties that appear in a straightforward application of the QRPA in ${^{12}C}$, and we demonstrate that it is imperative to use the projected QRPA (PQRPA). Satisfactory results, not only for the weak processes among the ground states of the triad $\\{{{^{12}B},{^{12}C},{^{12}N}}\\}$, but also for the inclusive ones are obtained. We sketch as well a new formalism for the neutrino-nucleus interaction that furnishes very simple final formulae for the muon capture rate and neutrino induced cross sections.

  7. Modular Stirling Radioisotope Generator

    Science.gov (United States)

    Schmitz, Paul C.; Mason, Lee S.; Schifer, Nicholas A.

    2016-01-01

    High-efficiency radioisotope power generators will play an important role in future NASA space exploration missions. Stirling Radioisotope Generators (SRGs) have been identified as a candidate generator technology capable of providing mission designers with an efficient, high-specific-power electrical generator. SRGs high conversion efficiency has the potential to extend the limited Pu-238 supply when compared with current Radioisotope Thermoelectric Generators (RTGs). Due to budgetary constraints, the Advanced Stirling Radioisotope Generator (ASRG) was canceled in the fall of 2013. Over the past year a joint study by NASA and the Department of Energy (DOE) called the Nuclear Power Assessment Study (NPAS) recommended that Stirling technologies continue to be explored. During the mission studies of the NPAS, spare SRGs were sometimes required to meet mission power system reliability requirements. This led to an additional mass penalty and increased isotope consumption levied on certain SRG-based missions. In an attempt to remove the spare power system, a new generator architecture is considered, which could increase the reliability of a Stirling generator and provide a more fault-tolerant power system. This new generator called the Modular Stirling Radioisotope Generator (MSRG) employs multiple parallel Stirling convertor/controller strings, all of which share the heat from the General Purpose Heat Source (GPHS) modules. For this design, generators utilizing one to eight GPHS modules were analyzed, which provided about 50 to 450 W of direct current (DC) to the spacecraft, respectively. Four Stirling convertors are arranged around each GPHS module resulting in from 4 to 32 Stirling/controller strings. The convertors are balanced either individually or in pairs, and are radiatively coupled to the GPHS modules. Heat is rejected through the housing/radiator, which is similar in construction to the ASRG. Mass and power analysis for these systems indicate that specific

  8. Radioisotopes as Political Instruments, 1946-1953.

    Science.gov (United States)

    Creager, Angela N H

    2009-01-01

    The development of nuclear "piles," soon called reactors, in the Manhattan Project provided a new technology for manufacturing radioactive isotopes. Radioisotopes, unstable variants of chemical elements that give off detectable radiation upon decay, were available in small amounts for use in research and therapy before World War II. In 1946, the U.S. government began utilizing one of its first reactors, dubbed X-10 at Oak Ridge, as a production facility for radioisotopes available for purchase to civilian institutions. This program of the U.S. Atomic Energy Commission was meant to exemplify the peacetime dividends of atomic energy. The numerous requests from scientists outside the United States, however, sparked a political debate about whether the Commission should or even could export radioisotopes. This controversy manifested the tension in U.S. politics between scientific internationalism as a tool of diplomacy, associated with the aims of the Marshall Plan, and the desire to safeguard the country's atomic monopoly at all costs, linked to American anti-Communism. This essay examines the various ways in which radioisotopes were used as political instruments-both by the U.S. federal government in world affairs, and by critics of the civilian control of atomic energy-in the early Cold War.

  9. Radioisotopes in Industry

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Philip S. [Oak Ridge National Laboratory; Fuccillo, Jr., Domenic A. [Oak Ridge National Laboratory; Gerrard, Martha W. [Oak Ridge National Laboratory; Lafferty, Jr., Robert H. [Oak Ridge National Laboratory

    1967-05-01

    Radioisotopes, man-made radioactive elements, are used in industry primarily for measuring, testing and processing. How and why they are useful is the subject of this booklet. The booklet discusses their origin, their properties, their uses, and how they may be used in the future.

  10. The widths of the α decaying states of 12C within the three-cluster model

    Science.gov (United States)

    Fedorov, D. V.; Jensen, A. S.; Fynbo, H. O. U.

    2003-05-01

    We estimate the widths of the alpha decaying states of 12C (1+, 1-, 1-1, 2+, 2-, 3-, and 4+) within the three-alpha cluster model. We solve the Faddeev equations using the hyperspheric approach and calculate the decisive effective hyper-radial barriers. We calculate the widths in the WKB approximation and compare with experimental data.

  11. Wolf-Rayet stars and radioisotope production

    CERN Document Server

    Meynet, G

    1999-01-01

    Radioisotopes are natural clocks which can be used to estimate the age of the solar system. They also influence the shape of supernova light curves. In addition, the diffuse emission at 1.8 MeV from the decay of 26Al may provide a measure of the present day nucleosynthetic activity in the Galaxy. Therefore, even if radionuclides represent only a tiny fraction of the cosmic matter, they carry a unique piece of information. A large number of radioisotopes are produced by massive stars at the time of their supernova explosion. A more or less substantial fraction of them are also synthesized during the previous hydrostatic burning phases. These nuclides are then ejected either at the time of the supernova event, or through stellar winds during their hydrostatic burning phases. This paper focusses of the non explosive ejection of radionuclides by non-rotating or rotating Wolf-Rayet stars.

  12. RAPID ORBITAL DECAY IN THE 12.75-MINUTE BINARY WHITE DWARF J0651+2844

    Energy Technology Data Exchange (ETDEWEB)

    Hermes, J. J.; Winget, D. E. [Department of Astronomy, University of Texas at Austin, Austin, TX 78712 (United States); Kilic, Mukremin; Gianninas, A.; Kenyon, Scott J. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks Street, Norman, OK 73019 (United States); Brown, Warren R. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Allende Prieto, Carlos; Cabrera-Lavers, Antonio [Instituto de Astrofisica de Canarias, E-38205 La Laguna, Tenerife (Spain); Mukadam, Anjum S., E-mail: jjhermes@astro.as.utexas.edu [Department of Astronomy, University of Washington, Seattle, WA 98195 (United States)

    2012-10-01

    We report the detection of orbital decay in the 12.75-minute, detached binary white dwarf (WD) SDSS J065133.338+284423.37 (hereafter J0651). Our photometric observations over a 13 month baseline constrain the orbital period to 765.206543(55) s and indicate that the orbit is decreasing at a rate of (- 9.8 {+-} 2.8) Multiplication-Sign 10{sup -12} s s{sup -1} (or -0.31 {+-} 0.09 ms yr{sup -1}). We revise the system parameters based on our new photometric and spectroscopic observations: J0651 contains two WDs with M{sub 1} = 0.26 {+-} 0.04 M{sub Sun} and M{sub 2} = 0.50 {+-} 0.04 M{sub Sun }. General relativity predicts orbital decay due to gravitational wave radiation of (- 8.2 {+-} 1.7) Multiplication-Sign 10{sup -12} s s{sup -1} (or -0.26 {+-} 0.05 ms yr{sup -1}). Our observed rate of orbital decay is consistent with this expectation. J0651 is currently the second-loudest gravitational wave source known in the milli-Hertz range and the loudest non-interacting binary, which makes it an excellent verification source for future missions aimed at directly detecting gravitational waves. Our work establishes the feasibility of monitoring this system's orbital period decay at optical wavelengths.

  13. Woody debris volume depletion through decay: implications for biomass and carbon accounting

    Science.gov (United States)

    Fraver, Shawn; Milo, Amy M.; Bradford, John B.; D'Amato, Anthony W.; Kenefic, Laura; Palik, Brian J.; Woodall, Christopher W.; Brissette, John

    2013-01-01

    Woody debris decay rates have recently received much attention because of the need to quantify temporal changes in forest carbon stocks. Published decay rates, available for many species, are commonly used to characterize deadwood biomass and carbon depletion. However, decay rates are often derived from reductions in wood density through time, which when used to model biomass and carbon depletion are known to underestimate rate loss because they fail to account for volume reduction (changes in log shape) as decay progresses. We present a method for estimating changes in log volume through time and illustrate the method using a chronosequence approach. The method is based on the observation, confirmed herein, that decaying logs have a collapse ratio (cross-sectional height/width) that can serve as a surrogate for the volume remaining. Combining the resulting volume loss with concurrent changes in wood density from the same logs then allowed us to quantify biomass and carbon depletion for three study species. Results show that volume, density, and biomass follow distinct depletion curves during decomposition. Volume showed an initial lag period (log dimensions remained unchanged), even while wood density was being reduced. However, once volume depletion began, biomass loss (the product of density and volume depletion) occurred much more rapidly than density alone. At the temporal limit of our data, the proportion of the biomass remaining was roughly half that of the density remaining. Accounting for log volume depletion, as demonstrated in this study, provides a comprehensive characterization of deadwood decomposition, thereby improving biomass-loss and carbon-accounting models.

  14. Radioisotopes for medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Carr, S. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia). Radiopharmaceuticals Division

    1998-03-01

    For more than 3 decades, the Australian Nuclear Science and Technology Organisation has been the country`s main supplier of radioisotopes for medical applications. The use of radioisotopes in medicine has revolutionised the diagnosis, management and treatment of many serious diseases such as cancer, heart disease and stroke. It is also beginning to play a key role in neurological disorders such as Parkinson and Alzheimers disease and epilepsy. More recently there has been considerable growth in the application of nuclear medicine to treat sport-related injuries - especially wrist, ankle and knees where more common techniques do not always enable accurate diagnosis. Australia is a recognised leader in nuclear medicine. This can be partially attributed to the close relationship between ANSTO and the medical community in providing opportunities to develop and evaluate new agents to support more effective patient care. A list of commercial isotopes produced in the reactor or the cyclotron and used in medical applications is given. Nuclear medicine plays an important role in the clinical environment and the timely supply of radioisotopes is a key element. ANSTO will continue to be the premier supplier of currently available and developing isotopes to support the health and well being of the Australian community 2 tabs., 1 fig.

  15. Correlated emission of three {alpha}-particles in the {beta}-decay of {sup 12}N

    Energy Technology Data Exchange (ETDEWEB)

    Fynbo, H.O.U.; Oinonen, M.; Weissman, L. [EP Division, CERN, CH-1211 Geneve 23 (Switzerland); Prezado, Y.; Borge, M.J.G.; Tengblad, O. [Instituto Estructura de la Materia, CSIC, Serrano 113bis, E-28006 Madrid (Spain); Aeystoe, J.; Dendooven, P.; Huang, W.; Huikari, J.; Jones, P.; Wang, Y. [Department of Physics, University of Jyvaeskylae, FIN-40351 Jyvaeskylae (Finland); Bergmann, U.C.; Jeppesen, H.; Riisager, K.; Vogelius, I.S. [Institut for Fysik og Astronomi, Aarhus Universitet, DK-8000 Aarhus C (Denmark); Jonson, B.; Meister, M.; Nyman, G. [Experimentell Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Rolander, K.W. [Fysiska Institutionen, Stockholms Universitet, Box 6730, S-113 85 Stockholm (Sweden)

    2002-10-01

    The {beta}-decay of {sup 12}N is used to populate {alpha}-emitting excited states in {sup 12}C. The {alpha}-particles from the break-up of both the 10.3 MeV and 12.71 MeV states were measured in coincidence with an efficient detector setup consisting of two double-sided Si strip detectors. The break-up of the 12.71 MeV 1{sup +} state is an interesting testing ground for the different descriptions of multi-particle break-up, whereas the properties of the 10.3 MeV state, which under some astrophysical conditions is relevant for the production of {sup 12}C in stars, are poorly known. First results from the analysis of the data is presented and compared with Monte Carlo simulations. (orig.)

  16. Properties of the {sup 12}C 10 MeV state determined through {beta}-decay

    Energy Technology Data Exchange (ETDEWEB)

    Diget, C.A. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark); Barker, F.C. [Department of Theoretical Physics, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200 (Australia); Borge, M.J.G. [Instituto Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Cederkaell, J. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Fedosseev, V.N. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Fraile, L.M. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Fulton, B.R. [Department of Physics, University of York, Heslington, YO10 5DD (United Kingdom); Fynbo, H.O.U. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark)]. E-mail: fynbo@phys.au.dk; Jeppesen, H.B. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark); Jonson, B. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Koester, U. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Meister, M. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Nilsson, T. [ISOLDE-CERN, CH-1211 Geneva 23 (Switzerland); Nyman, G. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Prezado, Y. [Instituto Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Riisager, K. [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark); Rinta-Antila, S. [Department of Physics, University of Jyvaeskylae, FIN-40351 Jyvaeskylae (Finland); Tengblad, O. [Instituto Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Turrion, M. [Instituto Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Wilhelmsen, K. [Fundamental Fysik, Chalmers Tekniska Hoegskola, S-412 96 Goeteborg (Sweden); Aeystoe, J. [Department of Physics, University of Jyvaeskylae, FIN-40351 Jyvaeskylae (Finland); Helsinki Institute of Physics, University of Helsinki, FIN-00014 Helsinki (Finland)

    2005-10-03

    The {beta}-delayed triple-{alpha} particle decay of {sup 12}B has been measured with a setup that favours coincidence detection. A broad state in {sup 12}C, previously reported around 10 MeV, has been seen and its properties determined through R-matrix analysis of the excitation spectrum. The spin and parity are 0{sup +}. Interference between this state and the Hoyle state at 7.654 MeV has a marked influence on the spectrum. The coupling between the two states makes it difficult to determine the resonance energy.

  17. $\\beta$- decay of the proton-rich T$_{z} = -1/2$ nucleus, $^{71}$Kr

    CERN Document Server

    Oinonen, M; Äystö, J; Baumann, P; Didierjean, François; Honkanen, J A; Huck, A; Huyse, M; Knipper, A; Marguier, G; Novikov, Yu N; Popov, A; Ramdhane, M; Seliverstov, D M; Van Duppen, P; Walter, G

    1997-01-01

    $\\beta$- decay of the T$_{z}$ = - 1/2 nuclide $^{71}$Kr has been studied at the ISOLDE PSB Facility at CERN. $^{71}$Kr ions were produced in spallation reactions in a Nb foil using the 1 GeV proton beam and studied by means of $\\beta$-delayed proton, $\\beta$- and $\\gamma$-ray spectroscopy. The half-life and the $\\beta$-decay energy of $^{71}$Kr were determined using the decay of protons and positrons. These results: T$_{1/2}$ = 100 ± 3 ms and $Q_\\textrm{EC}$ = 10$^{14}$ ± 0.32 MeV and the first observation of the b-branch to the 207 keV level in $^{71}$Br makes the extension of the systematics of Gamow-Teller matrix elements of mirror nuclei up to A = 71 possible. Gamow-Teller strength of the same magnitude as that of the $fp$-shell mirror nuclei is observed for the ground state transition.

  18. Radioisotope Power System Pool Concept

    Science.gov (United States)

    Rusick, Jeffrey J.; Bolotin, Gary S.

    2015-01-01

    Advanced Radioisotope Power Systems (RPS) for NASA deep space science missions have historically used static thermoelectric-based designs because they are highly reliable, and their radioisotope heat sources can be passively cooled throughout the mission life cycle. Recently, a significant effort to develop a dynamic RPS, the Advanced Stirling Radioisotope Generator (ASRG), was conducted by NASA and the Department of Energy, because Stirling based designs offer energy conversion efficiencies four times higher than heritage thermoelectric designs; and the efficiency would proportionately reduce the amount of radioisotope fuel needed for the same power output. However, the long term reliability of a Stirling based design is a concern compared to thermoelectric designs, because for certain Stirling system architectures the radioisotope heat sources must be actively cooled via the dynamic operation of Stirling converters throughout the mission life cycle. To address this reliability concern, a new dynamic Stirling cycle RPS architecture is proposed called the RPS Pool Concept.

  19. U.S. Space Radioisotope Power Systems and Applications: Past, Present and Future

    Science.gov (United States)

    Cataldo, Robert L.; Bennett, Gary L.

    2011-01-01

    Radioisotope power systems (RPS) have been essential to the U.S. exploration of outer space. RPS have two primary uses: electrical power and thermal power. To provide electrical power, the RPS uses the heat produced by the natural decay of a radioisotope (e.g., plutonium-238 in U.S. RPS) to drive a converter (e.g., thermoelectric elements or Stirling linear alternator). As a thermal power source the heat is conducted to whatever component on the spacecraft needs to be kept warm; this heat can be produced by a radioisotope heater unit (RHU) or by using the excess heat of a radioisotope thermoelectric generator (RTG). As of 2010, the U.S. has launched 41 RTGs on 26 space systems. These space systems have ranged from navigational satellites to challenging outer planet missions such as Pioneer 10/11, Voyager 1/2, Galileo, Ulysses, Cassini and the New Horizons mission to Pluto. In the fall of 2011, NASA plans to launch the Mars Science Laboratory (MSL) that will employ the new Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) as the principal power source. Hundreds of radioisotope heater units (RHUs) have been launched to provide warmth to Apollo 11, used to provide heating of critical components in a seismic experiment package, Pioneer 10/11, Voyager 1/2, Galileo, Cassini, Mars Pathfinder, MER rovers, etc. to provide temperature control to critical spacecraft electronics and other mechanical devices such as propulsion system propellant valves. A radioisotope (electrical) power source or system (RPS) consists of three basic elements: (1) the radioisotope heat source that provides the thermal power, (2) the converter that transforms the thermal power into electrical power and (3) the heat rejection radiator. Figure 1 illustrates the basic features of an RPS. The idea of a radioisotope power source follows closely after the early investigations of radioactivity by researchers such as Henri Becquerel (1852-1908), Marie Curie (1867-1935), Pierre Curie (1859

  20. Decay rate of critical fluctuations in ethane + carbon dioxide mixtures near the critical line including the critical azeotrope

    Science.gov (United States)

    Chang, R. F.; Doiron, T.; Pegg, I. L.

    1986-03-01

    Using the technique of photon correlation spectroscopy we have measured the decay rate of critical fluctuations in mixtures of ethane and carbon dioxide of various compositions including a near-azeotropic mixture. Our experimental data indicate that there is only one dominant mode of fluctuations and the decay rate is well described by the predictions of the mode-coupling theory with the exponent v=0.63 for all compositions. The decay rate, its background contributions, the shear viscosity, and the correlation length for the mixtures appear to interpolate simply between those of ethane and carbon dioxide.

  1. Decay rate of critical fluctuations in ethane+carbon dioxide mixtures near the critical line including the critical azeotrope

    Energy Technology Data Exchange (ETDEWEB)

    Chang, R.F.; Doiron, T.; Pegg, I.L.; Hanley, H.J.M.; Cezairliyan, A.

    1986-03-01

    Using the technique of photon correlation spectroscopy we have measured the decay rate of critical fluctuations in mixtures of ethane and carbon dioxide of various compositions including a near-azeotropic mixture. Our experimental data indicate that there is only one dominant mode of fluctuations and the decay rate is well described by the predictions of the mode-coupling theory with the exponent v=0.63 for all compositions. The decay rate, its background contributions, the shear viscosity, and the correlation length for the mixtures appear to interpolate simply between those of ethane and carbon dioxide.

  2. Milliwatt Radioisotope Stirling Convertor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Studies of potential space missions have highlighted the need for very small electric power supplies for a variety of applications. The light weight radioisotope...

  3. Medical application of radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chang Woon; Lim, S. M.; Kim, E. H. [and others

    2000-05-01

    In this project, we studied following subjects: 1. Clinical research for radionuclide therapy 2. Development of in vitro assay method with radioisotope 3. Development of binary therapy; Boron neutron capture therapy and photodynamic therapy 4. Development of diagnostic methods in radionuclide imaging. The results can be applied for the following objectives: (1) Radionuclide therapy will be applied in clinical practice to treat the cancer patients or other diseases in multi-center trial (2) The newly developed monoclonal antibodies and biomolecules can be used in biology, chemistry or other basic life science research (3) The new methods for the analysis of therapeutic effects, such as dosimetry, and quantitative analysis methods of radioactivity, can be applied in basic research, such as radiation oncology and radiation biology (4) The result of the project will be expected to develop the new radioimmunoassay for drug monitoring following the clinical experiments (5) Boron porphyrin has been successfully labeled with iodine. This enables the pharmacodynamic study of the boron compound in human body (6) A method to evaluate the biological effect of neutrons on tumor cells has been developed (7) The establishment of macro- and microscopic dose assessment using alpha-track autoradiography (8) Clinical application of PDT in bladder cancers, oropharyngeal cancer and skin cancer (9) Radionuclide imaging of estrogen receptor in breast cancer, lipid metabolism, gene therapy, cancers, brain function and heart disease.

  4. Efficient Radioisotope Energy Transfer by Gold Nanoclusters for Molecular Imaging.

    Science.gov (United States)

    Volotskova, Olga; Sun, Conroy; Stafford, Jason H; Koh, Ai Leen; Ma, Xiaowei; Cheng, Zhen; Cui, Bianxiao; Pratx, Guillem; Xing, Lei

    2015-08-26

    Beta-emitting isotopes Fluorine-18 and Yttrium-90 are tested for their potential to stimulate gold nanoclusters conjugated with blood serum proteins (AuNCs). AuNCs excited by either medical radioisotope are found to be highly effective ionizing radiation energy transfer mediators, suitable for in vivo optical imaging. AuNCs synthesized with protein templates convert beta-decaying radioisotope energy into tissue-penetrating optical signals between 620 and 800 nm. Optical signals are not detected from AuNCs incubated with Technetium-99m, a pure gamma emitter that is used as a control. Optical emission from AuNCs is not proportional to Cerenkov radiation, indicating that the energy transfer between the radionuclide and AuNC is only partially mediated by Cerenkov photons. A direct Coulombic interaction is proposed as a novel and significant mechanism of energy transfer between decaying radionuclides and AuNCs.

  5. Practical methods for a direct calculation of Delta I=1/2 K to pipi Decay

    Science.gov (United States)

    Liu, Q.

    A direct calculation of the complex $\\Delta I=1/2$ kaon decay amplitude is notoriously difficult because of the presence of disconnected graphs. Here we describe and demonstrate two practical methods to defeat this problem: the EigCG algorithm and the use of time-separated $\\pi-\\pi$ sources. With a fine tuned EigCG implementation for domain wall fermions, the calculation of light quark propagators is accelerated by a factor of 5-10 on a variety of lattices from small ($16^3\\times32\\times16$) to large ($32^3\\times64\\times32$). In addition, a substantial reduction in noise is achieved by separating each of the sources for the two pions in the time direction by 2-5 lattice spacings. These methods are combined in a calculation of $K$ to $\\pi\\pi$ threshold decay using a $24^3\\times64\\times16$ volume and 329 MeV pions. These methods result in non-zero signals for both Re($A_0$) and Im($A_0$) from 138 gauge configurations.

  6. Probing the statistical decay and alpha-clustering effects in 12c+12c and 14n+10b reactions

    CERN Document Server

    Morelli, Luca; Agostino, M D; Bruno, M; Gulminelli, F; Cinausero, M; Degerlier, M; Fabris, D; Gramegna, F; Marchi, T; Barlini, S; Bini, M; Casini, G; Gelli, N; Lopez, A; Pasquali, G; Piantelli, S; Valdre', S

    2013-01-01

    An experimental campaign has been undertaken at INFN Laboratori Nazionali di Legnaro, Italy, in order to progress in our understanding of the statistical properties of light nuclei at excitation energies above particle emission threshold, by measuring exclusive data from fusion-evaporation reactions. A first reaction 12C+12C at 7.9 AMeV beam energy has been measured, using the GARFIELD+Ring Counter experimental setup. Fusion-evaporation events have been exclusively selected. The comparison to a dedicated Hauser-Feshbach calculation allows us to give constraints on the nuclear level density at high excitation energy for light systems ranging from C up to Mg. Out-of-equilibrium emission has been evidenced and attributed both to entrance channel effects favoured by the cluster nature of reaction partners and, in more dissipative events, to the persistence of cluster correlations well above the 24Mg threshold for 6 alphas decay. The 24Mg compound nucleus has been studied with a new measurement 14N + 10B at 5.7 AM...

  7. Alpha indirect conversion radioisotope power source

    Energy Technology Data Exchange (ETDEWEB)

    Sychov, Maxim [TRACE Photonics Inc., 1680 West Polk, Charleston, IL 61920 (United States)], E-mail: msychov@yahoo.com; Kavetsky, Alexandr; Yakubova, Galina; Walter, Gabriel; Yousaf, Shahid; Lin, Qian; Chan, Doris; Socarras, Heather; Bower, Kenneth [TRACE Photonics Inc., 1680 West Polk, Charleston, IL 61920 (United States)

    2008-02-15

    Advantages of radioisotope-powered electric generators include long service life, wide temperature range operation and high-energy density. We report development of a long-life generator based on indirect conversion of alpha decay energy. Prototyping used 300 mCi Pu-238 alpha emitter and AlGaAs photovoltaic cells designed for low light intensity conditions. The alpha emitter, phosphor screens, and voltaic arrays were assembled into a power source with the following characteristics: I{sub sc}=14 {mu}A; U{sub oc}=2.3 V; power output -21 {mu}W. Using this prototype we have powered an eight-digit electronic calculator and wrist watch.

  8. Probing the Statistical Decay and α-clustering effects in 12C + 12C and 14N + 10B reactions

    Science.gov (United States)

    Morelli, L.; Baiocco, G.; D'Agostino, M.; Bruno, M.; Gulminelli, F.; Cinausero, M.; Degerlier, M.; Fabris, D.; Gramegna, F.; Marchi, T.; Barlini, S.; Bini, M.; Casini, G.; Gelli, N.; Lopez, A.; Pasquali, G.; Piantelli, S.; Valdrè, S.

    2014-03-01

    An experimental campaign has been undertaken at Laboratori Nazionali di Legnaro (LNL INFN), Italy, in order to progress in our understanding of the statistical properties of light nuclei at excitation energies above particle emission threshold, by measuring exclusive data from fusion-evaporation reactions. On the experimental side, a first reaction: 12C+12C at 95 MeV beam energy has been measured, using the GARFIELD + Ring Counter (RCo) apparatuses. Fusion-evaporation events have been exclusively selected out of the entire data set. The comparison to a dedicated Hauser-Feshbach calculation allows us to give constraints on the nuclear level density at high excitation energy for light systems ranging from C up to Mg. Out-of-equilibrium aα emission has been evidenced and attributed both to an entrance channel effect (favoured by the cluster nature of reaction partners), and, in more dissipative events, to the persistence of cluster correlations well above the 24Mg threshold for 6 α's decay. In order to study the same 24Mg compound nucleus at similar excitation energy with respect to this first reaction a new measurement, 14N + 10B at 5.7 A.MeV, was performed at LNL laboratories with the same experimental setup. The comparison between the two systems would allow us to further constrain the level density of light nuclei in the mass-excitation energy range of interest. In this perspective, deviations from a statistical behaviour can be used as a tool to get information on nuclear clustering, both in the ground-state for projectile and target and in the hot source formed in the collision.

  9. Probing the Statistical Decay and α-clustering effects in 12C + 12C and 14N + 10B reactions

    Directory of Open Access Journals (Sweden)

    Morelli L.

    2014-03-01

    Full Text Available An experimental campaign has been undertaken at Laboratori Nazionali di Legnaro (LNL INFN, Italy, in order to progress in our understanding of the statistical properties of light nuclei at excitation energies above particle emission threshold, by measuring exclusive data from fusion-evaporation reactions. On the experimental side, a first reaction: 12C+12C at 95 MeV beam energy has been measured, using the GARFIELD + Ring Counter (RCo apparatuses. Fusion-evaporation events have been exclusively selected out of the entire data set. The comparison to a dedicated Hauser-Feshbach calculation allows us to give constraints on the nuclear level density at high excitation energy for light systems ranging from C up to Mg. Out-of-equilibrium aα emission has been evidenced and attributed both to an entrance channel effect (favoured by the cluster nature of reaction partners, and, in more dissipative events, to the persistence of cluster correlations well above the 24Mg threshold for 6 α’s decay. In order to study the same 24Mg compound nucleus at similar excitation energy with respect to this first reaction a new measurement, 14N + 10B at 5.7 A.MeV, was performed at LNL laboratories with the same experimental setup. The comparison between the two systems would allow us to further constrain the level density of light nuclei in the mass-excitation energy range of interest. In this perspective, deviations from a statistical behaviour can be used as a tool to get information on nuclear clustering, both in the ground-state for projectile and target and in the hot source formed in the collision.

  10. Pulsational Pair-instability Model for Superluminous Supernova PTF12dam: Interaction and Radioactive Decay

    Science.gov (United States)

    Tolstov, Alexey; Nomoto, Ken’ichi; Blinnikov, Sergei; Sorokina, Elena; Quimby, Robert; Baklanov, Petr

    2017-02-01

    Being a superluminous supernova, PTF12dam can be explained by a 56Ni-powered model, a magnetar-powered model, or an interaction model. We propose that PTF12dam is a pulsational pair-instability supernova, where the outer envelope of a progenitor is ejected during the pulsations. Thus, it is powered by a double energy source: radioactive decay of 56Ni and a radiative shock in a dense circumstellar medium. To describe multicolor light curves and spectra, we use radiation-hydrodynamics calculations of the STELLA code. We found that light curves are well described in the model with 40 M⊙ ejecta and 20–40 M⊙ circumstellar medium. The ejected 56Ni mass is about 6 M⊙, which results from explosive nucleosynthesis with large explosion energy (2–3) × 1052 erg. In comparison with alternative scenarios of pair-instability supernova and magnetar-powered supernova, in the interaction model, all the observed main photometric characteristics are well reproduced: multicolor light curves, color temperatures, and photospheric velocities.

  11. Does The $\\triangle I ={1/2}$ Rule Hold In D And B $\\to \\pi \\pi$ Decays

    CERN Document Server

    Guo, Peng; Li, Xue-Qian; Guo, Peng; He, Xiao-Gang; Li, Xue-Qian

    2004-01-01

    Although two pion decays of $K$,$D$ and $B$ have similar isospin structures, there are dramatic differences in the ratios $R_K$ and $R_{D,B}$ of amplitudes from $\\Delta I =3/2$ and $\\Delta I =1/2$ interactions. In $K\\to \\pi\\pi$ decays there is the famous $\\Delta I =1/2$ rule with $R_K = 1/22$, whereas in $B(D) \\to \\pi\\pi$ decays the ratios $R_{D,B}$ are of order one and therefore there is no such a rule. In this work we study isospin decay amplitudes in $B (D)\\to \\pi\\pi$ using the QCD factorization. The results are consistent with observations that there is no $\\Delta I =1/2$ rule. We show that the effects of re-scattering between the two pions produced via the weak transition can play a crucial rule in understanding the differences between $B(D)\\to \\pi\\pi$ and $K\\to \\pi\\pi$ decays.

  12. Litter decay controlled by temperature, not soil properties, affecting future soil carbon.

    Science.gov (United States)

    Gregorich, Edward G; Janzen, Henry; Ellert, Benjamin H; Helgason, Bobbi L; Qian, Budong; Zebarth, Bernie J; Angers, Denis A; Beyaert, Ronald P; Drury, Craig F; Duguid, Scott D; May, William E; McConkey, Brian G; Dyck, Miles F

    2017-04-01

    Widespread global changes, including rising atmospheric CO2 concentrations, climate warming and loss of biodiversity, are predicted for this century; all of these will affect terrestrial ecosystem processes like plant litter decomposition. Conversely, increased plant litter decomposition can have potential carbon-cycle feedbacks on atmospheric CO2 levels, climate warming and biodiversity. But predicting litter decomposition is difficult because of many interacting factors related to the chemical, physical and biological properties of soil, as well as to climate and agricultural management practices. We applied (13) C-labelled plant litter to soil at ten sites spanning a 3500-km transect across the agricultural regions of Canada and measured its decomposition over five years. Despite large differences in soil type and climatic conditions, we found that the kinetics of litter decomposition were similar once the effect of temperature had been removed, indicating no measurable effect of soil properties. A two-pool exponential decay model expressing undecomposed carbon simply as a function of thermal time accurately described kinetics of decomposition. (R(2)  = 0.94; RMSE = 0.0508). Soil properties such as texture, cation exchange capacity, pH and moisture, although very different among sites, had minimal discernible influence on decomposition kinetics. Using this kinetic model under different climate change scenarios, we projected that the time required to decompose 50% of the litter (i.e. the labile fractions) would be reduced by 1-4 months, whereas time required to decompose 90% of the litter (including recalcitrant fractions) would be reduced by 1 year in cooler sites to as much as 2 years in warmer sites. These findings confirm quantitatively the sensitivity of litter decomposition to temperature increases and demonstrate how climate change may constrain future soil carbon storage, an effect apparently not influenced by soil properties.

  13. Observation of $B^0_s\\rightarrow\\chi_{c1}\\phi$ decay and study of $B^0\\rightarrow\\chi_{c1,2}K^{*0}$ decays

    CERN Document Server

    Aaij, R; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amerio, S; Amhis, Y; Anderlini, L; Anderson, J; Andreassen, R; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Baesso, C; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bauer, Th; Bay, A; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bettler, M -O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bowen, E; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Burducea, I; Bursche, A; Busetto, G; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carranza-Mejia, H; Carson, L; Carvalho Akiba, K; Casse, G; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Cenci, R; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Couturier, B; Cowan, G A; Craik, D C; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; Davis, A; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Derkach, D; Deschamps, O; Dettori, F; Di Canto, A; Di Ruscio, F; Dijkstra, H; Dogaru, M; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Furfaro, E; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garofoli, J; Garosi, P; Garra Tico, J; Garrido, L; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Giubega, L; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hamilton, B; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hartmann, T; He, J; Head, T; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicheur, A; Hicks, E; Hill, D; Hoballah, M; Holtrop, M; Hombach, C; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Hussain, N; Hutchcroft, D; Hynds, D; Iakovenko, V; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jans, E; Jaton, P; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Kaballo, M; Kandybei, S; Kanso, W; Karacson, M; Karbach, T M; Kenyon, I R; Ketel, T; Keune, A; Khanji, B; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J -P; Lefèvre, R; Leflat, A; Lefrançois, J; Leo, S; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Li Gioi, L; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lohn, S; Longstaff, I; Lopes, J H; Lopez-March, N; Lu, H; Lucchesi, D; Luisier, J; Luo, H; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Manca, G; Mancinelli, G; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Maurice, E; Mazurov, A; Mc Skelly, B; McCarthy, J; McNab, A; McNulty, R; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M -N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mordà, A; Morello, M J; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neubert, S; Neufeld, N; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nicol, M; Niess, V; Niet, R; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Oyanguren, A; Pal, B K; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petridis, K; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pietrzyk, B; Pilař, T; Pinci, D; Playfer, S; Plo Casasus, M; Polci, F; Polok, G; Poluektov, A; Polyakov, I; Polycarpo, E; Popov, A; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pritchard, A; Prouve, C; Pugatch, V; Puig Navarro, A; Punzi, G; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Rives Molina, V; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodriguez Perez, P; Roiser, S; Romanovsky, V; Romero Vidal, A; Rouvinet, J; Ruf, T; Ruffini, F; Ruiz, H; Ruiz Valls, P; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salustino Guimaraes, V; Salzmann, C; Sanmartin Sedes, B; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Sirendi, M; Skwarnicki, T; Smith, N A; Smith, E; Smith, J; Smith, M; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Sun, L; Swientek, S; Syropoulos, V; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tresch, M; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urner, D; Ustyuzhanin, A; Uwer, U; Vagnoni, V; Valenti, G; Vallier, A; Van Dijk, M; Vazquez Gomez, R; Vazquez Regueiro, P; Vázquez Sierra, C; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Vieira, D; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; Waldi, R; Wallace, C; Wallace, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wicht, J; Wiechczynski, J; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wimberley, J; Wishahi, J; Witek, M; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, Z; Yang, Z; Young, R; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhokhov, A; Zhong, L; Zvyagin, A

    2013-01-01

    The first observation of the decay $B^0_s\\rightarrow\\chi_{c1}\\phi$ and a study of $B^0\\rightarrow\\chi_{c1,2}K^{*0}$ decays are presented. The analysis is performed using a dataset, corresponding to an integrated luminosity of 1.0 fb$^{-1}$, collected by the LHCb experiment in pp collisions at a centre-of-mass energy of 7 TeV. The following ratios of branching fractions are measured: \\begin{equation*} \\begin{array}{lll} \\dfrac{\\cal{B}(B^0_s\\rightarrow\\chi_{c1}\\phi)}{\\cal{B}(B^0_s\\rightarrow J/\\psi\\phi)} &=& (18.9 \\pm1.8\\,(stat)\\pm1.3\\,(syst)\\pm0.8\\,(\\cal{B})) \\times 10^{-2}, \\\\ \\dfrac{\\cal{B}(B^0\\rightarrow\\chi_{c1}K^{*0})}{\\cal{B}(B^0\\rightarrow J/\\psi K^{*0})} &=& (19.8 \\pm1.1\\,(stat)\\pm1.2\\,(syst)\\pm0.9\\,(\\cal{B})) \\times 10^{-2}, \\\\ \\dfrac{\\cal{B}(B^0\\rightarrow\\chi_{c2}K^{*0})}{\\cal{B}(B^0\\rightarrow\\chi_{c 1}K^{*0})} &=& (17.1 \\pm5.0\\,(stat)\\pm1.7\\,(syst)\\pm1.1\\,(\\cal{B})) \\times 10^{-2}, \\\\ \\end{array} \\end{equation*} where the third uncertainty is due to the limited knowledge o...

  14. Physical and bacterial controls on inorganic nutrients and dissolved organic carbon during a sea ice growth and decay experiment

    DEFF Research Database (Denmark)

    Zhou, J.; Delille, B.; Kaartokallio, H.

    2014-01-01

    We investigated how physical incorporation, brine dynamics and bacterial activity regulate the distribution of inorganic nutrients and dissolved organic carbon (DOC) in artificial sea ice during a 19-day experiment that included periods of both ice growth and decay. The experiment was performed...... temperatures and bulk ice salinities, we derived the brine volume fractions, brine salinities and Rayleigh numbers. The temporal evolution of these physical parameters indicates that there was two main stages in the brine dynamics: bottom convection during ice growth, and brine stratification during ice decay...

  15. High purity materials as targets for radioisotope production: Needs and challenges

    Indian Academy of Sciences (India)

    V Shivarudrappa; K V Vimalnath

    2005-07-01

    Radionuclides have become powerful and indispensable tools in many endeavours of human activities, most importantly in medicine, industry, biology and agriculture, apart from R&D activities. Ready availability of radionuclides in suitable radiochemical form, its facile detection and elegant tracer concepts are responsible for their unprecedented use. Application of radioisotopes in medicine has given birth to a new branch, viz. nuclear medicine, wherein radioisotopes are used extensively in the diagnosis and treatment of variety of diseases including cancer. Artificial transmutation of an element employing thermal neutrons in a reactor or high energy particle accelerators (cyclotrons) are the routes of radioisotope production world over. Availability of high purity target materials, natural or enriched, are crucial for any successful radioisotope programme. Selection of stable nuclides in suitable chemical form as targets with desired isotopic and chemical purity are among the important considerations in radioisotope production. Mostly the oxide, carbonate or the metal itself are the preferred target forms for neutron activation in a research reactor. Chemical impurities, particularly from the elements of the same group, put a limitation on the purity of the final radioisotope product. Whereas the isotopic impurities result in the production of undesirable radionuclidic impurities, which affect their effective utilization. Isotope Group, BARC, is in the forefront of radioisotope production and supply in the country, meeting demands for gamut of radioisotope applications indigenously for over four decades now. Radioisotopes such as 131I, 99Mo, 32P, 51Cr, 153Sm, 82Br, 203Hg, 198Au etc are produced in TBq quantities every month and supplied to several users and to Board of Radiation and Isotope Technology (BRIT). Such a large production programme puts a huge demand on the reliable sources of availability of high purity target materials which are at present mostly met

  16. The widths of the {alpha} decaying states of {sup 12}C within the three-cluster model

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, D.V.; Jensen, A.S.; Fynbo, H.O.U

    2003-05-05

    We estimate the widths of the alpha decaying states of {sup 12}C (1{sup +}, 1{sup -}, 1{sup -1}, 2{sup +}, 2{sup -}, 3{sup -}, and 4{sup +}) within the three-alpha cluster model. We solve the Faddeev equations using the hyperspheric approach and calculate the decisive effective hyper-radial barriers. We calculate the widths in the WKB approximation and compare with experimental data.

  17. Rapid Orbital Decay in the 12.75-minute WD+WD Binary J0651+2844

    CERN Document Server

    Hermes, J J; Brown, Warren R; Winget, D E; Prieto, Carlos Allende; Gianninas, A; Mukadam, Anjum S; Cabrera-Lavers, Antonio; Kenyon, Scott J

    2012-01-01

    We report the detection of orbital decay in the 12.75-min, detached binary white dwarf (WD) SDSS J065133.338+284423.37 (hereafter J0651). Our photometric observations over a 13-month baseline constrain the orbital period to 765.206543(55) s and indicate the orbit is decreasing as a rate of (-9.8 +/- 2.8) x 10^(-12) s/s (or -0.31 +/- 0.09 ms/yr). We revise the system parameters based on our new photometric and spectroscopic observations: J0651 contains two WDs with M1 = 0.26 +/- 0.04 Msun and M2 = 0.50 +/- 0.04 Msun. General relativity predicts orbital decay due to gravitational wave radiation of (-8.2 +/- 1.7) x 10^(-12) s/s (or -0.26 +/- 0.05 ms/yr). Our observed rate of orbital decay is consistent with this expectation. J0651 is currently the second-loudest gravitational wave source known in the milli-Hertz range and the loudest non-interacting binary, which makes it an excellent verification source for future missions aimed at directly detecting gravitational waves. Our work establishes the feasibility of ...

  18. Radioisotope Power: A Key Technology for Deep Space Explorations

    Science.gov (United States)

    Schmidt, George R.; Sutliff, Thomas J.; Duddzinski, Leonard

    2009-01-01

    A Radioisotope Power System (RPS) generates power by converting the heat released from the nuclear decay of radioactive isotopes, such as Plutonium-238 (Pu-238), into electricity. First used in space by the U.S. in 1961, these devices have enabled some of the most challenging and exciting space missions in history, including the Pioneer and Voyager probes to the outer solar system; the Apollo lunar surface experiments; the Viking landers; the Ulysses polar orbital mission about the Sun; the Galileo mission to Jupiter; the Cassini mission orbiting Saturn; and the recently launched New Horizons mission to Pluto. Radioisotopes have also served as a versatile heat source for moderating equipment thermal environments on these and many other missions, including the Mars exploration rovers, Spirit and Opportunity. The key advantage of RPS is its ability to operate continuously, independent of orientation and distance relative to the Sun. Radioisotope systems are long-lived, rugged, compact, highly reliable, and relatively insensitive to radiation and other environmental effects. As such, they are ideally suited for missions involving long-lived, autonomous operations in the extreme conditions of space and other planetary bodies. This paper reviews the history of RPS for the U.S. space program. It also describes current development of a new Stirling cycle-based generator that will greatly expand the application of nuclear-powered missions in the future.

  19. Development of Kabila rocket: A radioisotope heated thermionic plasma rocket engine

    Directory of Open Access Journals (Sweden)

    Kalomba Mboyi

    2015-04-01

    Full Text Available A new type of plasma rocket engine, the Kabila rocket, using a radioisotope heated thermionic heating chamber instead of a conventional combustion chamber or catalyst bed is introduced and it achieves specific impulses similar to the ones of conventional solid and bipropellant rockets. Curium-244 is chosen as a radioisotope heat source and a thermal reductive layer is also used to obtain precise thermionic emissions. The self-sufficiency principle is applied by simultaneously heating up the emitting material with the radioisotope decay heat and by powering the different valves of the plasma rocket engine with the same radioisotope decay heat using a radioisotope thermoelectric generator. This rocket engine is then benchmarked against a 1 N hydrazine thruster configuration operated on one of the Pleiades-HR-1 constellation spacecraft. A maximal specific impulse and power saving of respectively 529 s and 32% are achieved with helium as propellant. Its advantages are its power saving capability, high specific impulses and simultaneous ease of storage and restart. It can however be extremely voluminous and potentially hazardous. The Kabila rocket is found to bring great benefits to the existing spacecraft and further research should optimize its geometric characteristics and investigate the physical principals of its operation.

  20. Purifications of calcium carbonate and molybdenum oxide powders for neutrinoless double beta decay experiment, AMoRE

    Energy Technology Data Exchange (ETDEWEB)

    Park, HyangKyu [Center for Underground Physics, Institute for Basic Science, 70, Yuseong-daero 1689-gil, Yuseong-gu, Daejeon, Korea, 305-811 (Korea, Republic of)

    2015-08-17

    The AMoRE (Advanced Mo based Rare process Experiment) collaboration is going to use calcium molybdate crystals to search for neutrinoless double beta decay of {sup 100}Mo isotope. In order to make the crystal, we use calcium carbonate and molybdenum oxide powders as raw materials. Therefore it is highly necessary to reduce potential sources for radioactive backgrounds such as U and Th in the powders. In this talk, we will present our studies for purification of calcium carbonate and molybdenum oxide powders.

  1. Preliminary results of Delta I=1/2 and 3/2, K to pipi Decay Amplitudes from Lattice QCD

    Science.gov (United States)

    Liu, Q.

    We report a direct lattice calculation of the $K$ to $\\pi\\pi$ decay matrix elements for both $\\Delta I=1/2$ and $3/2$ channels on 2+1 flavor, domain wall fermion, $16^3\\times32$ lattices with zero $\\pi\\pi$ relative momentum and $m_\\pi=420$ MeV. All $K^0$ to $\\pi\\pi$ contractions are carefully listed and calculated. The decay into the isospin zero $\\pi\\pi$ final state, which receives contributions from the disconnected graphs, is very difficult to calculate, but a clear signal in the similar disconnected $\\pi\\pi$ correlator can be seen. Preliminary results, some with large errors, will be presented for the various contributions to the renormalized weak matrix elements $A_0$ and $A_2$. We obtain Re$(A_0)$ with $25%$ error in the case of zero momentum on shell decay, and find a factor of 6 enhancement for the $\\Delta I=1/2$ rule in the $420$ MeV pion system.

  2. {beta} decay of the proton-rich T{sub z}={minus}1/2 nucleus, {sup 71}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Oinonen, M.; Aeystoe, J.; Honkanen, A. [Department of Physics, University of Jyvaeskylae, P.O. Box 35, FIN-40351, Jyvaeskylae (Finland); Jokinen, A.; Aeystoe, J. [CERN, PPE Division, CH-1211 Geneva 23 (Switzerland); Baumann, P.; Didierjean, F.; Huck, A.; Knipper, A.; Ramdhane, M.; Walter, G. [CRN, CNRS-IN2P3, Universite Louis Pasteur, B.P. 28, F-67037 Strasbourg (France); Huyse, M.; Van Duppen, P. [Instituut voor Kern-en Stralingsfysica, University of Leuve n, Celestijnenlaan 200 D, B-3001 Leuven (Belgium); Marguier, G. [IPN, CNRS-IN2P3, Universite Claude Bernard, F-69622 Villeurb anne (France); Novikov, Y.; Popov, A.; Seliverstov, D.M. [St. Petersburg Nuclear Physics Institute, Gatchina, 188350 St. Pete rsburg, Russia] [CERN, CH-1211 Geneva 23 (Switzerland)

    1997-08-01

    {beta} decay of the T{sub z}={minus}1/2 nuclide {sup 71}Kr has been studied at the ISOLDE PSB Facility at CERN. {sup 71}Kr ions were produced in spallation reactions in a Nb foil using the 1 GeV proton beam and studied by means of {beta}-delayed proton, {beta}- and {gamma}-ray spectroscopy. The half-life and the {beta}-decay energy of {sup 71}Kr were determined using the decay of protons and positrons. These results: T{sub 1/2}=100{plus_minus}3ms and Q{sub EC}=10.14{plus_minus}0.32MeV and the first observation of the {beta} branch to the 207 keV level in {sup 71}Br makes the extension of the systematics of Gamow-Teller matrix elements of mirror nuclei up to A=71 possible. The Gamow-Teller strength of the same magnitude as that of the fp-shell mirror nuclei is observed for the ground-state transition. {copyright} {ital 1997} {ital The American Physical Society}

  3. {sup 12}C+{sup 16}O: Properties of sub-barrier resonance {gamma}-decay

    Energy Technology Data Exchange (ETDEWEB)

    Goasduff, A.; Courtin, S.; Haas, F.; Lebhertz, D.; Jenkins, D. G.; Fallis, J.; Ruiz, C.; Hutcheon, D. A.; Amandruz, P.-A.; Davis, C.; Hager, U.; Ottewell, D.; Ruprecht, G. [Universite de Strasbourg, IPHC, 23 rue du Loess 67037 Strasbourg (France) and CNRS, UMR7178, 67037 Strasbourg (France); GANIL, CEA/DSM-CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 5 (France); Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3 (Canada)

    2012-10-20

    In a recent experiment performed at Triumf using the Dragon 0 Degree-Sign spectrometer and its associated BGO array, the complete {gamma}-decay of the radiative capture channel below the Coulomb barrier has been measured for the first time. This measurement has been performed at two energies E{sub c.m.}= 6.6 and 7.2 MeV. A selective contribution of the entrance spins 2{sup +} and 3{sup -} has been evidenced which is consistent with existing results above the barrier.

  4. US Department of Energy radioisotope customers with summary of radioisotope shipments, FY 1988

    Energy Technology Data Exchange (ETDEWEB)

    Van Houten, N.C.

    1989-06-01

    Pacific Northwest Laboratory (PNL) prepared this edition of the radioisotope customer list at the request of the Office of Health and Environmental Research (ER-73), Office of Energy Research, US Department of Energy (DOE). This is the 25th report in a series dating from 1964. This report covers DOE radioisotope sales and distribution activities by its facilities to domestic, foreign and other DOE facilities for FY 1988. The report is divided into five sections: radioisotope suppliers, facility contacts, and radioisotopes or services supplied; a list of customers, suppliers, and radioisotopes purchased; a list of radioisotopes purchased cross-referenced to customer numbers; geographic locations of radioisotope customers; and radioisotope sales and transfers -- FY 1988. Radioisotopes not previously reported in this series of reports were argon-37, arsenic-72, arsenic-73, bismuth-207, gadolinium-151, rhenium-188, rhodium-101, selenium-72, xenon-123 and zirconium-88. The total value of DOE radioisotope sales for FY 1988 was $11.1 million, an increase of 3% from FY 1987.

  5. NASA's Radioisotope Power Systems - Plans

    Science.gov (United States)

    Hamley, John A.; Mccallum, Peter W.; Sandifer, Carl E., II; Sutliff, Thomas J.; Zakrajsek, June F.

    2015-01-01

    NASA's Radioisotope Power Systems (RPS) Program continues to plan and implement content to enable planetary exploration where such systems could be needed, and to prepare more advanced RPS technology for possible infusion into future power systems. The 2014-2015 period saw significant changes, and strong progress. Achievements of near-term objectives have enabled definition of a clear path forward in which payoffs from research investments and other sustaining efforts can be applied. The future implementation path is expected to yield a higher-performing thermoelectric generator design, a more isotope-fuel efficient system concept design, and a robust RPS infrastructure maintained effectively within both NASA and the Department of Energy. This paper describes recent work with an eye towards the future plans that result from these achievements.

  6. Linear accelerator for radioisotope production

    Energy Technology Data Exchange (ETDEWEB)

    Hansborough, L.D.; Hamm, R.W.; Stovall, J.E.

    1982-02-01

    A 200- to 500-..mu..A source of 70- to 90-MeV protons would be a valuable asset to the nuclear medicine program. A linear accelerator (linac) can achieve this performance, and it can be extended to even higher energies and currents. Variable energy and current options are available. A 70-MeV linac is described, based on recent innovations in linear accelerator technology; it would be 27.3 m long and cost approx. $6 million. By operating the radio-frequency (rf) power system at a level necessary to produce a 500-..mu..A beam current, the cost of power deposited in the radioisotope-production target is comparable with existing cyclotrons. If the rf-power system is operated at full power, the same accelerator is capable of producing an 1140-..mu..A beam, and the cost per beam watt on the target is less than half that of comparable cyclotrons.

  7. Radio-isotopic assays of vitamin B12: interest of Kappa index in a multicentric study. Dosages radio-isotopiques de la vitamine B12: interet du test Kappa dans une evaluation multicentrique

    Energy Technology Data Exchange (ETDEWEB)

    Fourre, C. (Hopital de Bicetre, 94 - le Kremlin-Bicetre (France)); Guiraud-Vitaux, F. (Hopital de Montfermeil, 93 (France)); Labriolle-Vaylet, C. de (Hopital Saint-Antoine, 75 - Paris (France)); Colas-Linhart, N. (Hopital Beaujon, 92 - Clichy (France))

    1993-12-01

    Owing to the lack of a reference technique and of an international cobalamin (vitamin B12) standard, and the large discrepancy between laboratory norms, the authors performed a multicentric study to compare five RIA kits usually used. First, classical tests were used to evaluate the analytical performances of each kit. Results did not demonstrate any superiority of one kit over another. Secondly, B12 values were classified among three categories (low, normal and high) characterized by laboratory and then manufacturer norms. The concordance between these two ''judgments'' was evaluated with the Kappa coefficient. In addition, the Kappa index proved that the norms supplied by the manufacturer were better than those of laboratories. But mean Kappa coefficient established for each norm gave us an insatisfactory result. Third, clinical informations allowed to improve the classification of the patients. New limits were defined for each technique and should be tested further, routinely in each laboratory. (author).

  8. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1986

    Energy Technology Data Exchange (ETDEWEB)

    Lamar, D.A.

    1987-10-01

    This document describes radioisotope distribution from DOE facilities to private firms including foreign and other DOE facilities. The information is divided into five sections: (1)isotope suppliers, facility contact, and isotopes or services supplied; (2) customers, suppliers, and isotopes purchased; (3) isotopes purchased cross-referenced with customer numbers; (4) geographic locations of radioisotope customers; and (5) radioisotope sales and transfers for fiscal year 1986.

  9. Chromatographic generator systems for the actinides and natural decay series elements

    Energy Technology Data Exchange (ETDEWEB)

    McAlister, D.R.; Horwitz, E.P. [PG Research Foundation, Lisle, IL (United States)

    2011-07-01

    This work describes chromatographic radionuclide generator systems for the production of actinides and natural decay series elements. The generator systems begin with alpha emitting parent radioisotopes with half-lives (T{sub 1/2}) of greater than one year and produce alpha or beta emitting radioisotopes with half-lives of hours to days. Chromatographic systems were chosen to minimize radiolytic damage to chromatographic supports, preserve the parent activity for repeated use, provide high purity daughter radionuclide tracers, and to minimize or eliminate the need for evaporation of solutions of the parent or daughter nuclides. Useful secondary separations involving the daughters of the initial parent radionuclide are also described. Separation systems for {sup 210}Bi, {sup 210}Po, {sup 211}Pb, {sup 212}Pb, {sup 223}Ra, {sup 224}Ra, {sup 225}Ra, {sup 225}Ac, {sup 227}Th, {sup 228}Th, {sup 231}Th, {sup 234}Th, and {sup 239}Np are outlined in detail. (orig.)

  10. Radioisotope Power Systems Technology Development Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Radioisotope Power Systems (RPS) is a multicenter, multiagency (with the Department of Energy (DOE)) program whose purpose is to manage the Science Mission...

  11. Medical Radioisotopes Production Without A Nuclear Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Van der Keur, H.

    2010-05-15

    This report is answering the key question: Is it possible to ban the use of research reactors for the production of medical radioisotopes? Chapter 2 offers a summarized overview on the history of nuclear medicine. Chapter 3 gives an overview of the basic principles and understandings of nuclear medicine. The production of radioisotopes and its use in radiopharmaceuticals as a tracer for imaging particular parts of the inside of the human body (diagnosis) or as an agent in radiotherapy. Chapter 4 lists the use of popular medical radioisotopes used in nuclear imaging techniques and radiotherapy. Chapter 5 analyses reactor-based radioisotopes that can be produced by particle accelerators on commercial scale, other alternatives and the advantages of the cyclotron. Chapter 6 gives an overview of recent developments and prospects in worldwide radioisotopes production. Chapter 7 presents discussion, conclusions and recommendations, and is answering the abovementioned key question of this report: Is it possible to ban the use of a nuclear reactor for the production of radiopharmaceuticals? Is a safe and secure production of radioisotopes possible?.

  12. Present status of research on Re-186 radiopharmaceuticals at Radioisotope Production Center

    Energy Technology Data Exchange (ETDEWEB)

    Mutalib, A. [Radioisotope Production Center, National Atomic Energy Agency Kawasan PUSPIPTEK, Serpong (Indonesia)

    1998-10-01

    Rhenium shows a close chemical similarity to technetium and is suitable for radiotherapy because the {beta}-emitting radionuclides {sup 186}Re (t{sub 1/2} 90 h, E{sub {beta}} = 1.1 MeV, E{sub {gamma}} = 137 keV) and {sup 188}Re (t{sub 1/2} = 17 h, E{sub {beta}} = 2.1 MeV). The {gamma}-emission associated with decay of {sup 186}Re is also useful in scintigraphy. The research on {sup 186}Re radiopharmaceuticals at Radioisotope Production Center has been carried out since April 1997. Interest in radioimmunotherapy (RIT) led us to the development of labeling antibodies with rhenium isotopes. Although there are several methods for coupling radiometal to antibody, we prefer an indirect labeling method in which a bifunctional chelating agent is used for coupling of {sup 186}Re to monoclonal antibodies. In this report we outline the study on the preparation of {sup 186}Re DMSA-TFP as precursor for labeling with monoclonal antibody. (author)

  13. Quantification of biodegradation for o-xylene and naphthalene using first order decay models, Michaelis-Menten kinetics and stable carbon isotopes

    Science.gov (United States)

    Blum, Philipp; Hunkeler, Daniel; Weede, Matthias; Beyer, Christof; Grathwohl, Peter; Morasch, Barbara

    2009-04-01

    At a former wood preservation plant severely contaminated with coal tar oil, in situ bulk attenuation and biodegradation rate constants for several monoaromatic (BTEX) and polyaromatic hydrocarbons (PAH) were determined using (1) classical first order decay models, (2) Michaelis-Menten degradation kinetics (MM), and (3) stable carbon isotopes, for o-xylene and naphthalene. The first order bulk attenuation rate constant for o-xylene was calculated to be 0.0025 d - 1 and a novel stable isotope-based first order model, which also accounted for the respective redox conditions, resulted in a slightly smaller biodegradation rate constant of 0.0019 d - 1 . Based on MM-kinetics, the o-xylene concentration decreased with a maximum rate of kmax = 0.1 µg/L/d. The bulk attenuation rate constant of naphthalene retrieved from the classical first order decay model was 0.0038 d - 1 . The stable isotope-based biodegradation rate constant of 0.0027 d - 1 was smaller in the reduced zone, while residual naphthalene in the oxic part of the plume further downgradient was degraded at a higher rate of 0.0038 d - 1 . With MM-kinetics a maximum degradation rate of kmax = 12 µg/L/d was determined. Although best fits were obtained by MM-kinetics, we consider the carbon stable isotope-based approach more appropriate as it is specific for biodegradation (not overall attenuation) and at the same time accounts for the dominant electron-accepting process. For o-xylene a field based isotope enrichment factor ɛfield of - 1.4 could be determined using the Rayleigh model, which closely matched values from laboratory studies of o-xylene degradation under sulfate-reducing conditions.

  14. Quantification of biodegradation for o-xylene and naphthalene using first order decay models, Michaelis-Menten kinetics and stable carbon isotopes.

    Science.gov (United States)

    Blum, Philipp; Hunkeler, Daniel; Weede, Matthias; Beyer, Christof; Grathwohl, Peter; Morasch, Barbara

    2009-04-01

    At a former wood preservation plant severely contaminated with coal tar oil, in situ bulk attenuation and biodegradation rate constants for several monoaromatic (BTEX) and polyaromatic hydrocarbons (PAH) were determined using (1) classical first order decay models, (2) Michaelis-Menten degradation kinetics (MM), and (3) stable carbon isotopes, for o-xylene and naphthalene. The first order bulk attenuation rate constant for o-xylene was calculated to be 0.0025 d(-1) and a novel stable isotope-based first order model, which also accounted for the respective redox conditions, resulted in a slightly smaller biodegradation rate constant of 0.0019 d(-1). Based on MM-kinetics, the o-xylene concentration decreased with a maximum rate of k(max)=0.1 microg/L/d. The bulk attenuation rate constant of naphthalene retrieved from the classical first order decay model was 0.0038 d(-1). The stable isotope-based biodegradation rate constant of 0.0027 d(-1) was smaller in the reduced zone, while residual naphthalene in the oxic part of the plume further downgradient was degraded at a higher rate of 0.0038 d(-1). With MM-kinetics a maximum degradation rate of k(max)=12 microg/L/d was determined. Although best fits were obtained by MM-kinetics, we consider the carbon stable isotope-based approach more appropriate as it is specific for biodegradation (not overall attenuation) and at the same time accounts for the dominant electron-accepting process. For o-xylene a field based isotope enrichment factor epsilon(field) of -1.4 could be determined using the Rayleigh model, which closely matched values from laboratory studies of o-xylene degradation under sulfate-reducing conditions.

  15. Development of radioisotope tracer technology

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Joon Ha; Lee, Myun Joo; Jung, Sung Hee; Park, Soon Chul; Lim, Dong Soon; Kim, Jae Ho; Lee, Jae Choon; Lee, Doo Sung; Cho, Yong Suk; Shin, Sung Kuan

    2000-04-01

    The purpose of this study is to develop the radioisotope tracer technology, which can be used in solving industrial and environmental problems and to build a strong tracer group to support the local industries. In relation to the tracer technology in 1999, experiments to estimate the efficiencies of a sludge digester of a waste water treatment plant and a submerged biological reactor of a dye industry were conducted. As a result, the tracer technology for optimization of facilities related to wastewater treatment has been developed and is believed to contribute to improve their operation efficiency. The quantification of the experimental result was attempted to improve the confidence of tracer technology by ECRIN program which basically uses the MCNP simulation principle. Using thin layer activation technique, wear of tappet shim was estimated. Thin layer surface of a tappet shim was irradiated by proton beam and the correlation between the measured activity loss and the amount of wear was established. The equipment was developed to adjust the energy of proton which collides with the surface of tappet. The tracer project team has participated into the tracer test for estimating the efficiency of RFCC system in SK cooperation. From the experiment the tracer team has obtained the primary elements to be considered for judging the efficiency of RFCC unit. By developing the tracer techniques to test huge industrial units like RFCC, the tracer team will be able to support the local industries that require technical services to solve any urgent trouble. (author)

  16. Unbound states in $^{12}$C populated by $\\gamma$-decay of the $(J^{\\pi},T) = (2^+,1)$ 16.11 MeV state

    CERN Document Server

    Laursen, K L; Kirsebom, O S; Madsøll, K S; Riisager, K

    2016-01-01

    The reaction $^{11}\\textrm{B}+p$ has been used to populate the $(J^\\pi,T) = (2^+,1)$ state at an excitation energy of 16.11 MeV in $^{12}$C. $\\gamma$-decay to unbound states in $^{12}$C are identified from analysis of the decay of the populated daughter states. Due to a new technique, $\\gamma$-decay to the 10.8 MeV 1$^-$ state is observed for the first time, and transitions to the 9.64 MeV (3$^-$) and 12.71 MeV (1$^+$) are confirmed. Unresolved transitions to natural parity strength at 10 MeV and 11.5-13 MeV are also observed. For all transitions partial widths are deduced

  17. Radioisotope Production for Medical and Physics Applications

    Science.gov (United States)

    Mausner, Leonard

    2012-10-01

    Radioisotopes are critical to the science and technology base of the US. Discoveries and applications made as a result of the availability of radioisotopes span widely from medicine, biology, physics, chemistry and homeland security. The clinical use of radioisotopes for medical diagnosis is the largest sector of use, with about 16 million procedures a year in the US. The use of ^99Mo/^99mTc generator and ^18F make up the majority, but ^201Tl, ^123I, ^111In, and ^67Ga are also used routinely to perform imaging of organ function. Application of radioisotopes for therapy is dominated by use of ^131I for thyroid malignancies, ^90Y for some solid tumors, and ^89Sr for bone cancer, but production of several more exotic species such as ^225Ac and ^211At are of significant current research interest. In physics ^225Ra is of interest for CP violation studies, and the actinides ^242Am, ^249Bk, and ^254Es are needed as targets for experiments to create superheavy elements. Large amounts of ^252Cf are needed as a fission source for the CARIBU experiment at ANL. The process of radioisotope production is multidisciplinary. Nuclear physics input based on nuclear reaction excitation function data is needed to choose an optimum target/projectile in order to maximize desired isotope production and minimize unwanted byproducts. Mechanical engineering is needed to address issues of target heating, induced mechanical stress and material compatibility of target and claddings. Radiochemists are involved as well since chemical separation to purify the desired final radioisotope product from the bulk target and impurities is also usually necessary. Most neutron rich species are produced at a few government and university reactors. Other radioisotopes are produced in cyclotrons in the commercial sector, university/hospital based facilities, and larger devices at the DOE labs. The landscape of US facilities, the techniques involved, and current supply challenges will be reviewed.

  18. [Variations in tooth decay rates among children 5 and 12 years old in Minas Gerais, Brazil].

    Science.gov (United States)

    Lucas, Simone Dutra; Portela, Margareth Crisóstomo; Mendonça, Lisette Lobato

    2005-01-01

    The aim of this ecological study was to analyze to what extent World Health Organization goals were met in relation to dental caries in 2000 in Minas Gerais State, Brazil, identifying factors associated with variation in DMFT and the occurrence of DMFT < or = 3 among 12-year-old children and in the percentage of caries-free 5-year-olds. Secondary data from different sources were used. Linear regression and multiple logistic regression techniques were applied to the analysis of the numerical and dichotomous dependent variables. Socioeconomic and dental services supply/utilization indicators were used as potential explanatory variables. The goals expressed by DMFT < or = 3 at 12 years and a minimum of 50% caries-free 5-year-olds were met by 37% and 9% of the State's municipalities, respectively. In general the dependent variables were associated with socioeconomic level, and no associations were identified with dental care. The results should not be generalized, but they do suggest inequities in oral health and the role played by socioeconomic factors and water fluoridation.

  19. End-on radioisotope thermoelectric generator impact tests

    Energy Technology Data Exchange (ETDEWEB)

    Reimus, M.A.H.; Hhinckley, J.E.

    1997-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of [sup 238]Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). The modular GPHS design was developed to address both survivability during launch abort and return from orbit. The first two RTG Impact Tests were designed to provide information on the response of a fully loaded RTG to end-on impact against a concrete target. The results of these tests indicated that at impact velocities up to 57 m/s the converter shell and internal components protect the GPHS capsules from excessive deformation. At higher velocities, some of the internal components of the RTG interact with the GPHS capsules to cause excessive localized deformation and failure.

  20. Radioisotope thermoelectric generator/thin fragment impact test

    Energy Technology Data Exchange (ETDEWEB)

    Reimus, M.A.H.; Hinckley, J.E.

    1998-12-31

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of {sup 238}Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the convertor housing, failure of one fueled clad, and release of a small quantity of fuel.

  1. Radioisotope thermoelectric generator/thin fragment impact test

    Science.gov (United States)

    Reimus, M. A. H.; Hinckley, J. E.

    1998-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of 238Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). Because the potential for a launch abort or return from orbit exists for any space mission, the heat source response to credible accident scenarios is being evaluated. This test was designed to provide information on the response of a loaded RTG to impact by a fragment similar to the type of fragment produced by breakup of the spacecraft propulsion module system (PMS). The results of this test indicated that impact of the RTG by a thin aluminum fragment traveling at 306 m/s may result in significant damage to the converter housing, failure of one fueled clad, and release of a small quantity of fuel.

  2. End-on radioisotope thermoelectric generator impact tests

    Science.gov (United States)

    Reimus, M. A. H.; Hinckley, J. E.

    1997-01-01

    The General-Purpose Heat Source (GPHS) provides power for space missions by transmitting the heat of 238Pu decay to an array of thermoelectric elements in a radioisotope thermoelectric generator (RTG). The modular GPHS design was developed to address both survivability during launch abort and return from orbit. The first two RTG Impact Tests were designed to provide information on the response of a fully loaded RTG to end-on impact against a concrete target. The results of these tests indicated that at impact velocities up to 57 m/s the converter shell and internal components protect the GPHS capsules from excessive deformation. At higher velocities, some of the internal components of the RTG interact with the GPHS capsules to cause excessive localized deformation and failure.

  3. Radioisotopes production for applications on the health; Produccion de radioisotopos para aplicaciones en la salud

    Energy Technology Data Exchange (ETDEWEB)

    Monroy G, F.; Alanis M, J., E-mail: fabiola.monroy@inin.gob.m [ININ, Departamento de Materiales Radiactivos, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2010-07-01

    In the Radioactive Materials Department of the Instituto Nacional de Investigaciones Nucleares (ININ) processes have been studied and developed for the radioisotopes production of interest in the medicine, research, industry and agriculture. In particular five new processes have been developed in the last 10 years by the group of the Radioactive Materials Research Laboratory to produce: {sup 99}Mo/{sup 99m}Tc and {sup 188}W/{sup 188}Re generators, the radio lanthanides: {sup 151}Pm, {sup 147}Pm, {sup 161}Tb, {sup 166}Ho, {sup 177}Lu, {sup 131}I and the {sup 32}P. All these radioisotopes are artificial and they can be produced in nuclear reactors and some of them in particle accelerators. The radioisotope generators are of particular interest, as those of {sup 99}Mo/{sup 99m}Tc and {sup 188}W/{sup 188}Re presented in this work, because they are systems that allow to produce an artificial radioisotope of interest continually, in these cases the {sup 99m}Tc and the {sup 188}Re, without the necessity of having a nuclear reactor or an particle accelerator. They are compact systems armored and sure perfectly of manipulating that, once the radioactive material has decayed, they do not present radiological risk some for the environment and the population. These systems are therefore of supreme utility in places where it is not had nuclear reactors or with a continuous radioisotope supply, due to their time of decaying, for its cost or for logistical problems in their supply, like it is the case of many hospital centers, of research or industries in our country. (Author)

  4. Radiopharmaceuticals in positron emission tomography: Radioisotope productions and radiolabelling procedures at the Austin and Repatriation Medical Centre

    Energy Technology Data Exchange (ETDEWEB)

    Tochon-Danguy, H.J.; Sachinidis, J.I.; Chan, J.G.; Cook, M. [Austin and Repatriation Medical Centre, Melbourne, VIC (Australia). Centre for Positron Emission Tomography

    1997-10-01

    Positron Emission Tomography (PET) is a technique that utilizes positron-emitting radiopharmaceuticals to map the physiology, biochemistry and pharmacology of the human body. Positron-emitting radioisotopes produced in a medical cyclotron are incorporated into compounds that are biologically active in the body. A scanner measures radioactivity emitted from a patient`s body and provides cross-sectional images of the distribution of these radiolabelled compounds in the body. It is the purpose of this paper to review the variety of PET radiopharmaceuticals currently produced at the Austin and Repatriation Medical Centre in Melbourne. Radioisotope production, radiolabelling of molecules and quality control of radiopharmaceuticals will be discussed. A few examples of their clinical applications will be shown as well. During the last five years we achieved a reliable routine production of various radiopharmaceuticals labelled with the four most important positron-emitters: oxygen-15 (t,{sub 1/2}=2min), nitrogen-13 (t{sub 1/2}= 10 min), carbon-11 (t{sub 1/2}=20 min) and fluorine-18 (t{sub 1/2}= 110 min). These radiopharmaceuticals include [{sup 15}O]oxygen, [{sup 15}O]carbon monoxide, [{sup 15}O]carbon dioxide, [{sup 15}O]water, [{sup 13}N]ammonia, [{sup 11}C]flumazenil, [{sup 11}C]SCH23390, [{sup 18}F]fluoromisonidazole and [{sup 18}F]fluoro-deoxy-glucose ([{sup 18}F]FDG). In addition, since the half life of [{sup 18}F] is almost two hours, regional distribution can be done, and the Austin and Repatriation Medical Centre is currently supplying [{sup 18}F]FDG in routine to other hospitals. Future new radiopharmaceuticals development include a [{sup 18}F]thymidine analog to measure cell proliferation and a [{sup 11}C]pyrroloisoquinoline to visualize serotonergic neuron abnormalities. (authors) 23 refs., 2 tabs.

  5. Kaon to Two Pions decays from Lattice QCD: Delta I = 1/2 rule and CP violation

    Science.gov (United States)

    Liu, Qi

    We report a direct lattice calculation of the K to pipi decay matrix elements for both the DeltaI=1/2 and 3/2 amplitudes A0 and A2 on a 2+1 flavor, domain wall fermion, 163x32x16 lattice ensemble and a 243x64x16 lattice ensemble. This is a complete calculation in which all contractions for the required ten, four-quark operators are evaluated, including the disconnected graphs in which no quark line connects the initial kaon and final two-pion states. These lattice operators are non-perturbatively renormalized using the Rome-Southampton method and the quadratic divergences are studied and removed. This is an important but notoriously difficult calculation, requiring high statistics on a large volume. In this work we take a major step towards the computation of the physicalK→pipi amplitudes by performing a complete calculation at unphysical kinematics with pions of mass 422 MeV and 329 MeV at rest in the kaon rest frame. With this simplification we are able to resolve Re(A0) from zero for the first time, with a 25% statistical error on the 163 lattice and 15% on the 243 lattice. The complex amplitude A2 is calculated with small statistical errors. We obtain the DeltaI=1/2 rule with an enhancement factor of 9.1(21) and 12.0(17) on these two ensembles. From the detailed analysis of the results we gain a deeper understanding of the origin of the DeltaI=1/2 rule. We also calculate the complex amplitude A0, a calculation central to understanding and testing the standard model of CP violation in the kaon system. The final result for the measure of direct CP violation, epsilon', calculated at unphysical kinematics has an order of 100% statistical error, so this only serves as an order of magnitude check.

  6. NASA's Radioisotope Power Systems Program Status

    Science.gov (United States)

    Dudzinski, Leonard A.; Hamley, John A.; McCallum, Peter W.; Sutliff, Thomas J.; Zakrajsek, June F.

    2013-01-01

    NASA's Radioisotope Power Systems (RPS) Program began formal implementation in December 2010. The RPS Program's goal is to make available RPS for the exploration of the solar system in environments where conventional solar or chemical power generation is impractical or impossible to meet mission needs. To meet this goal, the RPS Program manages investments in RPS system development and RPS technologies. The current keystone of the RPS Program is the development of the Advanced Stirling Radioisotope Generator (ASRG). This generator will be about four times more efficient than the more traditional thermoelectric generators, while providing a similar amount of power. This paper provides the status of the RPS Program and its related projects. Opportunities for RPS generator development and targeted research into RPS component performance enhancements, as well as constraints dealing with the supply of radioisotope fuel, are also discussed in the context of the next ten years of planetary science mission plans.

  7. Commercial Superconducting Electron Linac for Radioisotope Production

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, Terry Lee [Niowave, Inc., Lansing, MI (United States); Boulware, Charles H. [Niowave, Inc., Lansing, MI (United States); Hollister, Jerry L. [Niowave, Inc., Lansing, MI (United States); Jecks, Randall W. [Niowave, Inc., Lansing, MI (United States); Mamtimin, Mayir [Niowave, Inc., Lansing, MI (United States); Starovoitova, Valeriia [Niowave, Inc., Lansing, MI (United States)

    2015-08-13

    The majority of radioisotopes used in the United States today come from foreign suppliers or are generated parasitically in large government accelerators and nuclear reactors. Both of these restrictions limit the availability of radioisotopes and discourage the development and evaluation of new isotopes and for nuclear medicine, science, and industry. Numerous studies have been recommending development of dedicated accelerators for production of radioisotopes for over 20 years (Institute of Medicine, 1995; Reba, et al, 2000; National Research Council, 2007; NSAC 2009). The 2015 NSAC Long Range Plan for Isotopes again identified electron accelerators as an area for continued research and development. Recommendation 1(c) from the 2015 NSAC Isotope report specifically identifies electron accelerators for continued funding for the purpose of producing medical and industrial radioisotopes. Recognizing the pressing need for new production methods of radioisotopes, the United States Congress passed the American Medical Isotope Production Act of 2012 to develop a domestic production of 99Mo and to eliminate the use of highly enriched uranium (HEU) in the production of 99Mo. One of the advantages of high power electron linear accelerators (linacs) is they can create both proton- and neutron-rich isotopes by generating high energy x-rays that knock out protons or neutrons from stable atoms or by fission of uranium. This allows for production of isotopes not possible in nuclear reactors. Recent advances in superconducting electron linacs have decreased the size and complexity of these systems such that they are economically competitive with nuclear reactors and large, high energy accelerators. Niowave, Inc. has been developing a radioisotope production facility based on a superconducting electron linac with liquid metal converters.

  8. Thyroiditis: Radioisotope Scan Findings and Clinical Significance

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Chae; Han, Duck Sup; Park, Jung Suck; Kim, Se Jong; Park, Byung Lan; Kim, Byoung Geun [Kwangju Christian Hospital, Kwangju (Korea, Republic of)

    1991-07-15

    We analyzed Radioisotope scan findings of 46 patients of thyroiditis which were proven pathologically at K.C.H. The results were as follows 1) 45 patients were female, one was male and average age of patients was 37 years old. 2) The lesion site was predominant in both lobe (67%) Hashimoto's thyroiditis showed enlarged thyroid (85%) with cold nodule (20%), diffuse decreased activity (10%), while subacute thyroiditis was presented absent activity (53%), poor visualization (20%) or cold nodule (7%). 4) Radioisotope scan was valuable in evaluating function of thyroid gland and detection of lesion but there was a limit of pathological nature.

  9. Untreated severe dental decay: a neglected determinant of low Body Mass Index in 12-year-old Filipino children.

    NARCIS (Netherlands)

    Benzian, H.; Monse, B.; Heinrich-Weltzien, R.; Hobdell, M.; Mulder, J.; Palenstein Helderman, W.H. van

    2011-01-01

    BACKGROUND: Dental decay is the most common childhood disease worldwide and most of the decay remains untreated. In the Philippines caries levels are among the highest in the South East Asian region. Elementary school children suffer from high prevalence of stunting and underweight.The present study

  10. Drought indicated in carbon-13/carbon-12 ratios of southwestern tree rings

    Energy Technology Data Exchange (ETDEWEB)

    Leavitt, S.W. (Univ. of Wisconsin-Parkside, Kenosha (United States)); Long, A. (Univ. of Arizona, Tucson (United States))

    1989-04-01

    Stomatal closure during periods of moisture deficiency should theoretically lead to elevated {sup 13}C/{sup 12}C ratios as reduction of available CO{sub 2} leads to diminished photosynthetic discrimination against {sup 13}C in favor of {sup 12}C. Stable-carbon isotope ratio chronologies developed from 5-yr tree-ring groups at 17 sites in six southwestern states were tested for a drought relationship by first fitting a spline curve to each chronology to remove the long-term trend and calculating indices as the ratio of actual to spline curve value. The time series of Del Indices so developed are significantly correlated with 5-yr mean Palmer Hydrological Drought Indices and reconstructed July Palmer Drought Severity Indices from respective areas. Overall, in the period since 1790, and driest pentads were 1900-04 and 1960-64, whereas the wettest were 1980-84 and 1915-19. Maps of drought represented for two pentads seem to be reasonable representations, although spatial correlations of Del Indices with PHDI were generally not significant. These Del Index drought reconstructions may provide a useful measure of past physiological response to drought, although the present cost of analysis would prevent this from being a routine method.

  11. Decay constants in geochronology

    Institute of Scientific and Technical Information of China (English)

    IgorM.Villa; PaulR.Renne

    2005-01-01

    Geologic time is fundamental to the Earth Sciences, and progress in many disciplines depends critically on our ability to measure time with increasing accuracy and precision. Isotopic geochronology makes use of the decay of radioactive nuclides as a help to quantify the histories of rock, minerals, and other materials. Both accuracy and precision of radioisotopic ages are, at present, limited by those of radioactive decay constants. Modem mass spectrometers can measure isotope ratios with a precision of 10-4 or better. On the other hand, the uncertainties associated with direct half-life determinations are, in most cases, still at the percent level. The present short note briefly summarizes progress and problems that have been encountered during the Working Group's activity.

  12. List of DOE radioisotope customers with summary of radioisotope shipments, FY 1979

    Energy Technology Data Exchange (ETDEWEB)

    Burlison, J.S. (comp.)

    1980-06-01

    The fifteenth edition of the radioisotope customer list was prepared at the request of the Division of Financial Services, Office of the Assistant Secretary for Environment, Department of Energy (DOE). This document lists DOE's radioisotope production and distribution activities by its facilities at Argonne National Laboratory; Pacific Northwest Laboratory; Brookhaven National Laboratory; Hanford Engineering Development Laboratory; Idaho Operations Office; Los Alamos Scientific Laboratory; Mound Facility; Oak Ridge National Laboratory; Rocky Flats Area Office; Savannah River Laboratory; and UNC Nuclear Industries, Inc. The information is divided into five sections: Isotope suppliers, facility, contracts and isotopes or services supplied; alphabetical list of customers, and isotopes purchased; alphabetical list of isotopes cross-referenced to customer numbers; geographical location of radioisotope customers; and radioisotope sales and transfers-FY 1979.

  13. Precision measurement of the half-life and branching ratio of the T=1/2 mirror $\\beta$-decay of $^{37}$K

    CERN Multimedia

    We propose to study the T=1/2 mirror $\\beta$-decay of $^{37}$K. Nuclear mirror $\\beta$-decay is a competitive means to test the electroweak model by means of the high-precision measurement of V$_{ud}$ element of the CKM quark mixing matrix. One key ingredient to obtain V$_{ud}$ is the force of the transition, Ft, which has to be determined with a relative precision below 10$^{−3}$. This quantity is related to the half-life T$_{1/2}$ of the decaying nucleus, the branching ratio BR for this decay and the mass difference between the mother and daughter nucleus (Q value). Another important feature is the mixing ratio $\\rho$ between the Fermi and the Gamow-Teller character of the transition. In most cases, $\\rho$ is the major contributor to the uncertainty on Ft. Available data concerning T$_{1/2}$ and BR of $^{37}$K suffer from a lack of precision that will be easily reduced by a dedicated experiment.

  14. Development of radioisotope production in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Cabalfin, E.G. [Philippine Nuclear Research Institute, Quezon (Philippines)

    1998-10-01

    The Philippine Nuclear Research Institute (PNRI) started its activities on radioisotope production more than three decades ago, when the Philippine Research Reactor (PRR-1) started operating at its full rated power of 1 MW. Since then, several radionuclides in different chemical forms, were routinely produced and supplied for use in nuclear medicine, industry, agriculture, research and training, until the conversion of the PRR-1 to a 3 MW TRIGA type reactor. After the criticality test of the upgraded reactor, a leak was discovered in the pool liner. With the repair of the reactor still ongoing, routine radioisotope production activities have been reduced to dispensing of imported bulk {sup 131}I. In the Philippines, radioisotopes are widely used in nuclear medicine, with {sup 131}I and {sup 99m}Tc as the major radionuclides of interest. Thus the present radioisotope production program of PNRI is directed to meet this demand. With the technical assistance of the International Atomic Energy Agency (IAEA), PNRI is setting up a new {sup 131}I production facility. The in-cell equipment have been installed and tested using both inactive and active target, obtained from BATAN, Indonesia. In order to meet the need of producing {sup 99}Mo-{sup 99m}Tc generators, based on low specific activity reactor-produced {sup 99}Mo, research and development work on the preparation of {sup 99m}Tc gel generators is ongoing. (author)

  15. ILLUSTRATIONS OF RADIOISOTOPES--DEFINITIONS AND APPLICATIONS.

    Science.gov (United States)

    Atomic Energy Commission, Oak Ridge, TN. Div. of Technical Information.

    THIS PUBLICATION IS COMPOSED OF OVER 150 PAGES OF BLACK AND WHITE ILLUSTRATIONS DEALING WITH RADIOISOTOPES AND THEIR USES. THESE ILLUSTRATIONS CONSIST OF CHARTS, GRAPHS, AND PICTORIAL REPRESENTATIONS WHICH COULD BE PREPARED AS HANDOUTS, TRANSPARENCIES FOR OVERHEAD PROJECTION, OR WHICH COULD BE USED IN A NUMBER OF OTHER WAYS FOR PRESENTING SUCH…

  16. Contributions and Future of Radioisotopes in Medical, Industrial and Space Applications

    Science.gov (United States)

    Tingey, G. L.; Dix, G. P.; Wahlquist, E. J.

    1990-11-01

    There are 333 isotopes that have a half-life between 1 day and 100,000 years that have a wide variety of applications including public health, medicine,industrial technology, food technology and packaging, agriculture, energy supply, and national security. This paper provides an overview of some of the most extensive applications of radioisotopes including some observations of future uses. Examples are discussed that indicate that the use of radioisotopes is almost unlimited and will continue to grow. There is a growing need for future applications development and production. 12 refs., 1 tab. (BM)

  17. Contributions and future of radioisotopes in medical, industrial and space applications

    Energy Technology Data Exchange (ETDEWEB)

    Tingey, G.L.; Dix, G.P.; Wahlquist, E.J.

    1990-11-01

    There are 333 isotopes that have a half-life between 1 day and 100,000 years that have a wide variety of applications including public health, medicine,industrial technology, food technology and packaging, agriculture, energy supply, and national security. This paper provides an overview of some of the most extensive applications of radioisotopes including some observations of future uses. Examples are discussed that indicate that the use of radioisotopes is almost unlimited and will continue to grow. There is a growing need for future applications development and production. 12 refs., 1 tab. (BM)

  18. List of ERDA radioisotope (customers with summary of radioisotope shipments FY 1975

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, J.L.; Gano, S.R. (comp.)

    1976-01-01

    The twelfth edition of the ERDA radioisotope customer list has been prepared at the request of the Division of Biomedical and Environmental Research. The purpose of this document is to list the FY 1975 commercial radioisotope production and distribution activities of USERDA facilities at Argonne National Laboratory, Battelle, Pacific Northwest Laboratories, Brookhaven National Laboratory, United Nuclear Inc., Idaho Operations Office, Hanford Engineering Development Laboratory, Mound Laboratory, Oak Ridge National Laboratory, and Savannah River Plant. (TFD)

  19. The GLOBE Carbon Project: Integrating the Science of Carbon Cycling and Climate Change into K-12 Classrooms.

    Science.gov (United States)

    Ollinger, S. V.; Silverberg, S.; Albrechtova, J.; Freuder, R.; Gengarelly, L.; Martin, M.; Randolph, G.; Schloss, A.

    2007-12-01

    The global carbon cycle is a key regulator of the Earth's climate and is central to the normal function of ecological systems. Because rising atmospheric CO2 is the principal cause of climate change, understanding how ecosystems cycle and store carbon has become an extremely important issue. In recent years, the growing importance of the carbon cycle has brought it to the forefront of both science and environmental policy. The need for better scientific understanding has led to establishment of numerous research programs, such as the North American Carbon Program (NACP), which seeks to understand controls on carbon cycling under present and future conditions. Parallel efforts are greatly needed to integrate state-of-the-art science on the carbon cycle and its importance to climate with education and outreach efforts that help prepare society to make sound decisions on energy use, carbon management and climate change adaptation. Here, we present a new effort that joins carbon cycle scientists with the International GLOBE Education program to develop carbon cycle activities for K-12 classrooms. The GLOBE Carbon Cycle project is focused on bringing cutting edge research and research techniques in the field of terrestrial ecosystem carbon cycling into the classroom. Students will collect data about their school field site through existing protocols of phenology, land cover and soils as well as new protocols focused on leaf traits, and ecosystem growth and change. They will also participate in classroom activities to understand carbon cycling in terrestrial ecosystems, these will include plant- a-plant experiments, hands-on demonstrations of various concepts, and analysis of collected data. In addition to the traditional GLOBE experience, students will have the opportunity to integrate their data with emerging and expanding technologies including global and local carbon cycle models and remote sensing toolkits. This program design will allow students to explore research

  20. Observation of B{sub s}{sup 0}→χ{sub c1}ϕ decay and study of B{sup 0}→χ{sub c1,2}K{sup ⁎0} decays

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Adrover, C. [CPPM, Aix-Marseille Université, CNRS/IN2P3, Marseille (France); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); Albrecht, J. [Fakultät Physik, Technische Universität Dortmund, Dortmund (Germany); Alessio, F. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Alexander, M. [School of Physics and Astronomy, University of Glasgow, Glasgow (United Kingdom); Ali, S. [Nikhef National Institute for Subatomic Physics, Amsterdam (Netherlands); Alkhazov, G. [Petersburg Nuclear Physics Institute (PNPI), Gatchina (Russian Federation); Alvarez Cartelle, P. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Alves, A.A. [Sezione INFN di Roma La Sapienza, Roma (Italy); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Amato, S. [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro (Brazil); Amerio, S. [Sezione INFN di Padova, Padova (Italy); Amhis, Y. [LAL, Université Paris-Sud, CNRS/IN2P3, Orsay (France); Anderlini, L. [Sezione INFN di Firenze, Firenze (Italy); Anderson, J. [Physik-Institut, Universität Zürich, Zürich (Switzerland); Andreassen, R. [University of Cincinnati, Cincinnati, OH (United States); Andrews, J.E. [University of Maryland, College Park, MD (United States); and others

    2013-09-21

    The first observation of the decay B{sub s}{sup 0}→χ{sub c1}ϕ and a study of B{sup 0}→χ{sub c1,2}K{sup ⁎0} decays are presented. The analysis is performed using a dataset, corresponding to an integrated luminosity of 1.0 fb{sup −1}, collected by the LHCb experiment in pp collisions at a centre-of-mass energy of 7 TeV. The following ratios of branching fractions are measured: (table) where the third uncertainty is due to the limited knowledge of the branching fractions of χ{sub c}→J/ψγ modes.

  1. A comparison of PET imaging characteristics of various copper radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Heather Ann [North Western Medical Physics, Christie Hospital NHS Trust, Manchester (United Kingdom); University of Manchester Institute of Science and Technology, Department of Instrumentation and Analytical Science, Manchester (United Kingdom); Robinson, Simon; Julyan, Peter; Hastings, David [North Western Medical Physics, Christie Hospital NHS Trust, Manchester (United Kingdom); Zweit, Jamal [University of Manchester Institute of Science and Technology, Department of Instrumentation and Analytical Science, Manchester (United Kingdom); Paterson Institute for Cancer Research, Radiochemical Targeting and Imaging, Manchester (United Kingdom)

    2005-12-01

    PET radiotracers which incorporate longer-lived radionuclides enable biological processes to be studied over many hours, at centres remote from a cyclotron. This paper examines the radioisotope characteristics, imaging performance, radiation dosimetry and production modes of the four copper radioisotopes, {sup 60}Cu,{sup 61}Cu,{sup 62}Cu and{sup 64}Cu, to assess their merits for different PET imaging applications. Spatial resolution, sensitivity, scatter fraction and noise-equivalent count rate (NEC) are predicted for{sup 60}Cu,{sup 61}Cu,{sup 62}Cu and{sup 64}Cu using a model incorporating radionuclide decay properties and scanner parameters for the GE Advance scanner. Dosimetry for{sup 60}Cu,{sup 61}Cu and{sup 64}Cu is performed using the MIRD model and published biodistribution data for copper(II) pyruvaldehyde bis(N{sup 4}-methyl)thiosemicarbazone (Cu-PTSM). {sup 60}Cu and{sup 62}Cu are characterised by shorter half-lives and higher sensitivity and NEC, making them more suitable for studying the faster kinetics of small molecules, such as Cu-PTSM.{sup 61}Cu and{sup 64}Cu have longer half-lives, enabling studies of the slower kinetics of cells and peptides and prolonged imaging to compensate for lower sensitivity, together with better spatial resolution, which partially compensates for loss of image contrast.{sup 61}Cu-PTSM and{sup 64}Cu-PTSM are associated with radiation doses similar to [{sup 18}F]-fluorodeoxyglucose, whilst the doses for{sup 60}Cu-PTSM and{sup 62}Cu-PTSM are lower and more comparable with H{sub 2}{sup 15}O. The physical and radiochemical characteristics of the four copper isotopes make each more suited to some imaging tasks than others. The results presented here assist in selecting the preferred radioisotope for a given imaging application, and illustrate a strategy which can be extended to the majority of novel PET tracers. (orig.)

  2. A high power, Coated Particle Fuel Compact Radioisotope Heat Unit

    Science.gov (United States)

    King, Jeffrey C.; El-Genk, Mohamed S.

    2001-02-01

    A Coated Particle Fuel Compact, Radioisotope Heater Unit (CPFC-RHU) is proposed, which is capable of generating thermal power in excess of 27 W. This power output is more than four times that of a Hexa-RHU, which generates only six watts of thermal power. The design of the CPFC-RHU is identical to that of the Hexa-RHU, except that the six Pt-30Rh clad fuel pellets and the POCO graphite support in the latter are replaced with single-sized, ZrC coated, 238PuO2 fuel particles ~500 μm in diameter. In addition to fully retaining the helium gas generated by the radioactive decay of the fuel, the CPFC offers promise for enhanced safety. Thermal analyses of the CPFC-RHU show that while the Hexa-RHU is suitable for use in a radioisotope power system (RPS) operating at a converter hot-side temperature of 473 K, the CPFC-RHU could also be used at higher temperatures of 773 K and 973 K with a thermal efficiency >60%. Even at a 473 K converter hot-side temperature, the CPFC-RHU offers higher thermal efficiency (>90%) than the Hexa-RHU (~75%). The CPFC-RHU final design provides constant temperature, with almost uniform radial heat flux to the converter, for enhanced performance, better integration, and higher overall efficiency of the RPS. The present CPFC-RHU fills a gap in the power needs for future space missions requiring electric power of 1-15 W, from a single RPS. .

  3. Constraining Water Fluxes Through the Streambed of a Semi-arid Losing Stream Using Natural Tracers: Heat and Radioisotopes

    Science.gov (United States)

    Andersen, M. S.; Rau, G. C.; McCallum, A. M.; Meredith, K.; Acworth, I.

    2011-12-01

    Natural physical and chemical tracers of flow have different advantages and shortfalls based on their properties and the uncertainty related to variability in their source concentration. Each tracer integrates over a characteristic spatial-temporal scale depending on its decay or production rate and the flow velocity of the system. For instance heat tracing using diurnal temperature fluctuations will, at best, provide information about flow in the upper 1-2 m of the streambed before the signal is dampened below measurement resolution (Constantz et al. 2003). Conversely, radioisotopes used as tracers will integrate over increasing spatio-temporal scales for decreasing decay constants. Radioisotopes with comparatively slow decay rates will be less sensitive for resolving flow conditions on short spatio-temporal scales. Therefore, it is difficult to use these tracers in the streambed of losing systems because the radioactive decay is not discernible against the variability. Consequently, employing a combination of different tracers provides information on different parts of a given flow system. Comparing flow velocities derived from tracers integrating over different scales allows for separating the local hyporheic exchange from the regional groundwater recharge. A field experiment was carried out in a perennial section of the mostly ephemeral Maules Creek in NSW, Australia. Streambed temperature profiles were monitored at three sites along a 400 m stretch of the perennial reach. Streambed temperatures were recorded at 4 depths within one meter below the streambed. Water samples were collected from surface water, streambed and groundwater and analysed for stable water isotopes (18O and 2H) and radioisotopes (222Rn and 3H). The streambed heat profiles provided time series of surface water/groundwater exchange. Using this method it was found that the conditions were losing at all three sites with recharge rates varying between 0 and 0.4 m/d. 222Rn measurements in the

  4. Coated Particles Fuel Compact-General Purpose Heat Source for Advanced Radioisotope Power Systems

    Science.gov (United States)

    El-Genk, Mohamed S.; Tournier, Jean-Michel

    2003-01-01

    Coated Particles Fuel Compacts (CPFC) have recently been shown to offer performance advantage for use in Radioisotope Heater Units (RHUs) and design flexibility for integrating at high thermal efficiency with Stirling Engine converters, currently being considered for 100 We. Advanced Radioisotope Power Systems (ARPS). The particles in the compact consist of 238PuO2 fuel kernels with 5-μm thick PyC inner coating and a strong ZrC outer coating, whose thickness depends on the maximum fuel temperature during reentry, the fuel kernel diameter, and the fraction of helium gas released from the kernels and fully contained by the ZrC coating. In addition to containing the helium generated by radioactive decay of 238Pu for up to 10 years before launch and 10-15 years mission lifetime, the kernels are intentionally sized (>= 300 μm in diameter) to prevent any adverse radiological effects on reentry. This paper investigates the advantage of replacing the four iridium-clad 238PuO2 fuel pellets, the two floating graphite membranes, and the two graphite impact shells in current State-Of-The-Art (SOA) General Purpose Heat Source (GPHS) with CPFC. The total mass, thermal power, and specific power of the CPFC-GPHS are calculated as functions of the helium release fraction from the fuel kernels and maximum fuel temperature during reentry from 1500 K to 2400 K. For the same total mass and volume as SOA GPHS, the generated thermal power by single-size particles CPFC-GPHS is 260 W at Beginning-Of-Mission (BOM), versus 231 W for the GPHS. For an additional 10% increase in total mass, the CPFC-GPHS could generate 340 W BOM; 48% higher than SOA GPHS. The corresponding specific thermal power is 214 W/kg, versus 160 W/kg for SOA GPHS; a 34% increase. Therefore, for the same thermal power, the CPFC-GPHS is lighter than SOA GPHS, while it uses the same amount of 238PuO2 fuel and same aeroshell. For the same helium release fraction and fuel temperature, binary-size particles CPFC-GPHS could

  5. New limits on Beyond Standard Model physics from a measurement of the half-life of the T=1/2 mirror decay of 19Ne

    CERN Document Server

    Broussard, L; Boswell, M S; Crowell, A S; Dendooven, P; Howell, C R; Kidd, M F; Jungmann, K; Kruithof, W L; Onderwater, C J G; Pattie, R W; Shidling, P D; Sohani, M; van der Hoek, D J; Rogachevskiy, A; Traykov, E; Versolato, O O; Willmann, L; Wilschut, H W; Young, A R

    2013-01-01

    The 1/2+ -> 1/2+ superallowed mixed mirror decay of 19Ne to 19F is excellently suited for high-precision studies of the weak interaction. However, there is some disagreement on the value of the half-life. In a new measurement we have determined this quantity to be T_{1/2} = 17.2832 +/- 0.0051_{(stat)} +/- 0.0066_{(sys)} seconds, which differs from the previous world average by 3 standard deviations. The impact of this measurement on limits for physics beyond the standard model such as the presence of tensor currents is discussed.

  6. Development of radioisotope labeled polymeric carriers

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Jin; Jeong, Jea Min; Hwang, Hyun Jeong [Ewha Womans University, Seoul (Korea)

    2000-04-01

    This research was performed with the aim of developing polymeric radioisotope or drug carriers for obtaining efficient diagnostic therapeutic efficacy. As polymers, polyethylene oxides, polylactides, polycaprolactone were chosen to prepare the devices including micelle system, microemulsion, nanospheres. In addition, anticancer drug loaded polylactide microparticulates were fabricated as a regional chemotherapeutics for the treatment of cancer. Technetium or radioactive iodine was labeled to the polymeric carriers via ligands such as DTPA and HPP, respectively. Labeling efficiency was above 90% and stable enough up to 24 hours. Moreover, injected polymer carriers demonstrated higher blood maintenance and bone uptake than Tin colloid, a control. These results suggested that radioisotope carrying polymeric particulate are promising tools for diagnosing blood vessels or bones. Besides, anticancer drug loaded particulates demonstrated appropriate maintenance of therapeutic concentration and localization. Therefore it was proposed that this therapeutic system may be potential as a cancer therapy modality. 20 refs., 24 figs.,5 tabs. (Author)

  7. Efficacy of supercritical carbon dioxide for nonthermal inactivation of Escherichia coli K12 in apple cider

    Science.gov (United States)

    This study evaluated the efficacy of a supercritical carbon dioxide (SCCO2) system with a gas-liquid porous metal contactor for eliminating Escherichia coli K12 in apple cider. Pasteurized, preservative-free apple cider was inoculated with E. coli K12 and processed using the SCCO2 system at CO2 conc...

  8. Characterizing the atomic mass surface beyond the proton drip line via a-decay measurements of the s1/2 ground state of 165Re and the h11/2 isomer in 161Ta

    CERN Document Server

    O'Donnell, D; Scholey, C; Bianco, L; Capponi, L; Carroll, R J; Darby, I G; Donosa, L; Drummond, M; Ertugral, F; Greenlees, P T; Grahn, T; Hauschild, K; Herzan, A; Jakobsson, U; Jones, P; Joss, D T; Julin, R; Juutinen, S; Ketelhut, S; Labiche, M; Leino, M; Lopez-Martens, A; Mullholland, K; Nieminen, P; Peura, P; Rahkila, P; Rinta-Antila, S; Ruotsalainen, P; Sandzelius, M; Saren, J; Saygi, B; Simpson, J; Sorri, J; Thornthwaite, A; Uusitalo, J; 10.1103/PhysRevC.86.064315

    2012-01-01

    The a-decay chains originating from the s1/2 and h11/2 states in 173Au have been investigated following fusion-evaporation reactions. Four generations of a radioactivities have been correlated with 173Aum leading to a measurement of the a decay of 161Tam. It has been found that the known a decay of 161Ta, which was previously associated with the decay of the ground state, is in fact the decay of an isomeric state. This work also reports on the first observation of prompt g rays feeding the ground state of 173Au. This prompt radiation was used to aid the study of the a-decay chain originating from the s1/2 state in 173Au. Three generations of a decays have been correlated with this state leading to the observation of a previously unreported activity which is assigned as the decay of 165Reg. This work also reports the excitation energy of an a-decaying isomer in 161Ta and the Q-value of the decay of 161Tag.

  9. Dynamical decay of 32S* and 31P* formed in 20Ne+12C and 19F+12C reactions, respectively, at E*CN = 60 MeV

    Directory of Open Access Journals (Sweden)

    Singh BirBikram

    2015-01-01

    Full Text Available The target-like C-yield in the decay of compound systems 32S* and 31P* formed in 20Ne+12C and 19F+12C reactions at E*CN=60 MeV, is studied for the contribution of fusion-fission (ff decay cross section σff and the deep inelastic (DI orbiting σorb from the compound nucleus (CN and non-compound nucleus nCN processes, respectively. The calculations are performed using the collective clusterization of fragments within the dynamical cluster-decay model (DCM of Gupta and collaborators. Besides studying the competition between ff and DI orbiting phenomenon in the C-yield of these systems, we exclusively investigate the preformation and barrier penetration probabilities P0 and P as a function of angular momentum ℓ values which subsequently affects the contributions of σff and σorb. For calculating the contribution of σff in the C-yield, we have added the contributions from all the minimized intermediate mass fragments (IMFs for Z=6 in the calculated fragmentation potentials for 32S* (IMFs 11,12,13C are minimized and for 31P* (IMFs 12,13C are minimized, while calculating subsequently, P0 and the P for these IMFs. The distribution of preformed clusters/fragments as a function of fragment mass visibly explore the nuclear structure effects for the C-yield in decay of these compound systems, wherein, it is shown to be more favoured in the decay of 31P* in comparison to 32S* decay. The contribution of σorb to the C-yield is calculated from P at different allowed ℓ-values (upto ℓmax and also P≤1 of the outgoing fragments (same as that in the entrance channel, i.e., P0=1. Though preliminary but useful results indicates the competition between the CN and nCN process in the C-yield for the compound system 32S* only while the decay of 31P* is of pure CN origin, as observed in the experimental study. The calculations are in good comparison with the available experimental data.

  10. Clinical study of radioisotope clearance from the cerebrospinal fluid space using single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kuchiwaki, H.; Nagasaka, M.; Takada, S.; Ishiguri, H.; Kameyama, H.; Aoyama, Y.

    1989-07-01

    Radioisotope cisternography with statistical analysis was evaluated in 18 patients with suspected hydrocephalus shown by conventional CT, and 4 control patients. Regions of interest were located at cisterna magna, basal cistern, lateral cistern Silvii, interhemispheric cistern, and lateral ventricle using three dimensional SPECT images. A value for constant K was determined for each exponential radioactivity decay curve. On the basis of SPECT-derived K values our patients were grouped into hydrocephalus, nonhydrocephalus, and control patients. Twelve of 14 hydrocephalus patients were treated by shunt operation. Our less-invasive method showed reliable criteria for assessing the cerebrospinal fluid circulation. (orig.).

  11. Nuclear and Radioisotope Propulsion and Power in the Atmosphere of Titan

    Science.gov (United States)

    Widdicombe, T.

    A brief history of the use of nuclear fuelled powerplant in space is given along with some working principles of the technology, and recent proposals for spacecraft for the exploration of Titan utilising radioisotope generators are surveyed. Nuclear reaction engines are studied with specific consideration given to their use in Titan's atmosphere, and speculative modifications to one particular spacecraft concept originally conceived of for the exploration of Mars are proposed. A hybrid device producing mechanical power from nuclear decay heat is also suggested for future investigation.

  12. Vitrified chemically bonded phosphate ceramics for immobilization of radioisotopes

    Science.gov (United States)

    Wagh, Arun S.

    2016-04-05

    A method of immobilizing a radioisotope and vitrified chemically bonded phosphate ceramic (CBPC) articles formed by the method are described. The method comprises combining a radioisotope-containing material, MgO, a source of phosphate, and optionally, a reducing agent, in water at a temperature of less than 100.degree. C. to form a slurry; curing the slurry to form a solid intermediate CBPC article comprising the radioisotope therefrom; comminuting the intermediate CBPC article, mixing the comminuted material with glass frits, and heating the mixture at a temperature in the range of about 900 to about 1500.degree. C. to form a vitrified CBPC article comprising the radioisotope immobilized therein.

  13. Efficient, Long-Lived Radioisotope Power Generator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Radiation Monitoring Devices, Inc., (RMD) proposes to develop an alternative very long term, radioisotope power source with thermoelectric power conversion with...

  14. Markets for reactor-produced non-fission radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, R.G.

    1995-01-01

    Current market segments for reactor produced radioisotopes are developed and reported from a review of current literature. Specific radioisotopes studied in is report are the primarily selected from those with major medical or industrial markets, or those expected to have strongly emerging markets. Relative market sizes are indicated. Special emphasis is given to those radioisotopes that are best matched to production in high flux reactors such as the Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory or the High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory. A general bibliography of medical and industrial radioisotope applications, trends, and historical notes is included.

  15. A new adrenal computer imaging technique using dual-radioisotopes.

    Directory of Open Access Journals (Sweden)

    Ohashi,Teruhisa

    1981-06-01

    Full Text Available Computer processed adrenal imaging using dual-radioisotopes, 6 beta-iodomethyl-19-nor-cholest-5(10-en-3 beta-ol-131I and 99mTc-phytate was performed in 12 patients with primary aldosteronism and 4 with Cushing's syndrome due to adrenocortical tumor. Adreno-photoscanning and hepato-photoscanning were performed in the same position 2-4 days following intravenous administration of radiocholesterol. The scintigraphic information was stored on cassettes and scan subtraction and a digital-computer method for data smoothing were performed on an oscilloscope. The tumor site could be determined in all cases until day 4 by this computer processed image.

  16. The Contribution of the Three-Body Process in the Nonmesonic Weak Decay of the Λ12C Hypernucleus.

    Directory of Open Access Journals (Sweden)

    Takahashi T.

    2010-04-01

    Full Text Available The serious inconsistency problem between the values of experimental and theoretical Γn /Γp ratio of the nonmesonic weak decay of Λ hypernuclei has been resolved recently. We have shown that the reason behind the problem was the quenching of the nucleon yields which in turn was due to the contribution of the three-body process. We have measured that the branching ratio of the three-body process in nonmesonic weak decay, 0.29±0.13, is so large that the absolute values of Γn and Γp must be determined taking account of the contribution of the 3-body process. In this paper, the recent studies toward the finding of the 3-body process via the exclusive coincidence experiments are presented.

  17. Spin polarization of the Ar* 2p{sup -1}{sub 1/2} 4s and 2p{sup -1}{sub 1/2} 3d resonant Auger decay

    Energy Technology Data Exchange (ETDEWEB)

    Turri, G [Department of Physics, Western Michigan University, Kalamazoo, MI 49008 (United States); Lohmann, B [Institut fuer Theoretische Physik, Westfaelische Wilhelms-Universitaet Muenster, Wilhelm-Klemm-Strasse 9, D-48149 Muenster (Germany); Langer, B [Max-Born-Institut fuer Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2A, D-12489 Berlin (Germany); Snell, G [Department of Physics, Western Michigan University, Kalamazoo, MI 49008 (United States); Becker, U [Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin/Dahlem (Germany); Berrah, N [Department of Physics, Western Michigan University, Kalamazoo, MI 49008 (United States)

    2007-09-14

    The spin-resolved Auger decay of the Ar 2p{sup -1}{sub 1/2} 3d state was measured at moderate energy resolution and compared with the decay of the 2p{sup -1}{sub 1/2} 4s. The former shows a lower transferred spin polarization and a similar, if not higher, dynamical spin polarization, supporting the statement that a fully resolved spectrum is not a necessary condition for observing dynamical spin polarization. An interpretation of the spin polarization as configuration interaction induced effect in the final ionic state leads to partial agreement with our relativistic distorted wave calculation utilizing a 36 configuration state function basis set. Comparison of the experimental and numerical results leads to ambiguities for at least one Auger line. A hypothetical, qualitative interpretation is discussed.

  18. Mutations in genes involved in nonsense mediated decay ameliorate the phenotype of sel-12 mutants with amber stop mutations in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Aubert Sylvie

    2009-03-01

    Full Text Available Abstract Background Presenilin proteins are part of a complex of proteins that can cleave many type I transmembrane proteins, including Notch Receptors and the Amyloid Precursor Protein, in the middle of the transmembrane domain. Dominant mutations in the human presenilin genes PS1 and PS2 lead to Familial Alzheimer's disease. Mutations in the Caenorhabditis elegans sel-12 presenilin gene cause a highly penetrant egg-laying defect due to reduction of signalling through the lin-12/Notch receptor. Mutations in six spr genes (for suppressor of presenilin are known to strongly suppress sel-12. Mutations in most strong spr genes suppress sel-12 by de-repressing the transcription of the largely functionally equivalent hop-1 presenilin gene. However, how mutations in the spr-2 gene suppress sel-12 is unknown. Results We show that spr-2 mutations increase the levels of sel-12 transcripts with Premature translation Termination Codons (PTCs in embryos and L1 larvae. mRNA transcripts from sel-12 alleles with PTCs undergo degradation by a process known as Nonsense Mediated Decay (NMD. However, spr-2 mutations do not appear to affect NMD. Mutations in the smg genes, which are required for NMD, can restore sel-12(PTC transcript levels and ameliorate the phenotype of sel-12 mutants with amber PTCs. However, the phenotypic suppression of sel-12 by smg genes is nowhere near as strong as the effect of previously characterized spr mutations including spr-2. Consistent with this, we have identified only two mutations in smg genes among the more than 100 spr mutations recovered in genetic screens. Conclusion spr-2 mutations do not suppress sel-12 by affecting NMD of sel-12(PTC transcripts and appear to have a novel mechanism of suppression. The fact that mutations in smg genes can ameliorate the phenotype of sel-12 alleles with amber PTCs suggests that some read-through of sel-12(amber alleles occurs in smg backgrounds.

  19. Development of radioisotope preparation and application technology

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hyon Soo; Park, K. B.; Bang, H. S. [and others

    2000-04-01

    The purpose of this project is to develop RI production technology utility 'HANARO' and to construct a sound infra-structure for mass production and supply to domestic users. The developed contents and results are as follows: two types of rig for irradiation in reactor core were designed and manufactured. The safety of OR rig during irradiation was identified through various test and it is used for RI production. The prepared IR rig will be used to performance tests for safety. We prepared two welders and welding jigs for production of sealed sources, and equipments for quality control of the welded materials. Production processes and apparatus Cr-51, P-32, I-125 and Sr-89, were developed. Developed results would be used for routine production and supply of radioisotopes. The automatic Tc-99m extraction apparatus was supplied to Libya under IAEA support. For approval on special form radioactive material of the developed Ir-192 source assembly and projector documents were prepared and submitted to MOST. The high dose rate Ir-192 source(diameter 1.1 mm, length 5.2 mm) for RALS and the laser welding system for its fabrication were developed. Production technologies of Ir-192 sources for destructive test and medical therapy were transferred to private company for commercial supply. The chemical immobilization method based on the self-assemble monolayer of {omega}-functionalized thiol and the sensing scheme based on the beta-emitter labeling method were developed for the fabrication radioimmuno-sensors. Results of this study will be applied to mass production of radioisotopes 'HANARO' and are to contribute the advance of domestic medicine and industry related to radioisotopes.

  20. Miniaturized radioisotope solid state power sources

    Science.gov (United States)

    Fleurial, J.-P.; Snyder, G. J.; Patel, J.; Herman, J. A.; Caillat, T.; Nesmith, B.; Kolawa, E. A.

    2000-01-01

    Electrical power requirements for the next generation of deep space missions cover a wide range from the kilowatt to the milliwatt. Several of these missions call for the development of compact, low weight, long life, rugged power sources capable of delivering a few milliwatts up to a couple of watts while operating in harsh environments. Advanced solid state thermoelectric microdevices combined with radioisotope heat sources and energy storage devices such as capacitors are ideally suited for these applications. By making use of macroscopic film technology, microgenrators operating across relatively small temperature differences can be conceptualized for a variety of high heat flux or low heat flux heat source configurations. Moreover, by shrinking the size of the thermoelements and increasing their number to several thousands in a single structure, these devices can generate high voltages even at low power outputs that are more compatible with electronic components. Because the miniaturization of state-of-the-art thermoelectric module technology based on Bi2Te3 alloys is limited due to mechanical and manufacturing constraints, we are developing novel microdevices using integrated-circuit type fabrication processes, electrochemical deposition techniques and high thermal conductivity substrate materials. One power source concept is based on several thermoelectric microgenerator modules that are tightly integrated with a 1.1W Radioisotope Heater Unit. Such a system could deliver up to 50mW of electrical power in a small lightweight package of approximately 50 to 60g and 30cm3. An even higher degree of miniaturization and high specific power values (mW/mm3) can be obtained when considering the potential use of radioisotope materials for an alpha-voltaic or a hybrid thermoelectric/alpha-voltaic power source. Some of the technical challenges associated with these concepts are discussed in this paper. .

  1. Recent progress in radioisotope production in Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Le Van So [Radioisotope Dept., Nuclear Research Institute, Dalat (Viet Nam)

    1998-10-01

    This is a report on the recent progress in radioisotope production in Vietnam. Using a nuclear research reactor of 500 KW with continuous operation cycles of 100 hours a month, the production of some important radioisotopes used in nuclear medicine and research was routinely carried out. More than 80 per cent of irradiation capacity of reactor for radioisotope production were exploited. The radioactivity of more than 150 Ci of {sup 131}I, {sup 99}Mo-{sup 99m}Tc, {sup 32}P, {sup 51}Cr, {sup 153}Sm, {sup 46}Sc, {sup 192}Ir was produced annually. Radiopharmaceuticals such as {sup 131}I-Hippuran and in-vivo Kits for {sup 99m}Tc labelling were also prepared routinely and regularly. More than 10 in-vivo Kits including modern radiopharmaceuticals such as HmPAO kit were supplied to hospitals in Vietnam. The research on the improvement of dry distillation technology for production of {sup 131}I was carried out. As a result obtained a new distillation apparatus made from glass was successfully put to routine use in place of expensive quartz distillation furnace. We have also continued the research programme on the development of {sup 99m}Tc generators using low power research reactors. Gel technology using Zr- and Ti- molybdate gel columns for {sup 99m}Tc generator production was developed and improved continually. Portable {sup 99m}Tc generator using Zr-({sup 99}Mo) molybdate gel column and ZISORB adsorbent column for {sup 99m}Tc concentration were developed. The ZISORB adsorbent of high adsorption capacity for {sup 99}Mo and other parent radionuclides was also studied for the development purpose of alternative technology of {sup 99m}Tc and other different radionuclide generator systems. The studies on the preparation of therapeutic radiopharmaceuticals labelling with {sup 153}Sm and {sup 131}I such as {sup 153}Sm-EDTMP, {sup 131}I-MIBG were carried out. (author)

  2. Performance tuned radioisotope thermophotovoltaic space power system

    Science.gov (United States)

    Horne, W. E.; Morgan, M. D.; Saban, S. B.

    1998-01-01

    The trend in space exploration is to use many small, low-cost, special-purpose satellites instead of the large, high-cost, multipurpose satellites used in the past. As a result of this new trend, there is a need for lightweight, efficient, and compact radioisotope fueled electrical power generators. This paper presents an improved design for a radioisotope thermophotovoltaic (RTPV) space power system in the 10 W to 20 W class which promises up to 37.6 watts at 30.1% efficiency and 25 W/kg specific power. The RTPV power system concept has been studied and compared to radioisotope thermoelectric generators (RTG) radioisotope, Stirling generators and alkali metal thermal electric conversion (AMTEC) generators (Schock, 1995). The studies indicate that RTPV has the potential to be the lightest weight, most efficient and most reliable of the three concepts. However, in spite of the efficiency and light weight, the size of the thermal radiator required to eliminate excess heat from the PV cells and the lack of actual system operational performance data are perceived as obstacles to RTPV acceptance for space applications. Between 1994 and 1997 EDTEK optimized the key converter components for an RTPV generator under Department of Energy (DOE) funding administered via subcontracts to Orbital Sciences Corporation (OSC) and EG&G Mound Applied Technologies Laboratory (Horne, 1995). The optimized components included a resonant micromesh infrared bandpass filter, low-bandgap GaSb PV cells and cell arrays. Parametric data from these components were supplied to OSC who developed and analyzed the performance of 100 W, 20 W, and 10 W RTPV generators. These designs are described in references (Schock 1994, 1995 and 1996). Since the performance of each class of supply was roughly equivalent and simply scaled with size, this paper will consider the OSC 20 W design as a baseline. The baseline 20-W RTPV design was developed by Schock, et al of OSC and has been presented elsewhere. The

  3. Medical Radioisotope Data Survey: 2002 Preliminary Results

    Energy Technology Data Exchange (ETDEWEB)

    Siciliano, Edward R.

    2004-06-23

    A limited, but accurate amount of detailed information about the radioactive isotopes used in the U.S. for medical procedures was collected from a local hospital and from a recent report on the U.S. Radiopharmaceutical Markets. These data included the total number of procedures, the specific types of procedures, the specific radioisotopes used in these procedures, and the dosage administered per procedure. The information from these sources was compiled, assessed, pruned, and then merged into a single, comprehensive and consistent set of results presented in this report. (PIET-43471-TM-197)

  4. Medical Radioisotope Production in a Power-Flattened ADS Fuelled with Uranium and Plutonium Dioxides

    Directory of Open Access Journals (Sweden)

    Gizem Bakır

    2016-01-01

    Full Text Available This study presents the medical radioisotope production performance of a conceptual accelerator driven system (ADS. Lead-bismuth eutectic (LBE is selected as target material. The subcritical fuel core is conceptually divided into ten equidistant subzones. The ceramic (natural U, PuO2 fuel mixture and the materials used for radioisotope production (copper, gold, cobalt, holmium, rhenium, thulium, mercury, palladium, thallium, molybdenum, and yttrium are separately prepared as cylindrical rods cladded with carbon/carbon composite (C/C and these rods are located in the subzones. In order to obtain the flattened power density, percentages of PuO2 in the mixture of UO2 and PuO2 in the subzones are adjusted in radial direction of the fuel zone. Time-dependent calculations are performed at 1000 MW thermal fission power (Pth for one hour using the BURN card. The neutronic results show that the investigated ADS has a high neutronic capability, in terms of medical radioisotope productions, spent fuel transmutation and energy multiplication. Moreover, a good quasiuniform power density is achieved in each material case. The peak-to-average fission power density ratio is in the range of 1.02–1.28.

  5. SYNTHESIS AND CHARACTERIZATION OF HIGH MOLECULAR WEIGHT POLY(1,2-PROPYLENE CARBONATE-co-1,2-CYCLOHEXYLENE CARBONATE)USING ZINC COMPLEX CATALYST

    Institute of Scientific and Technical Information of China (English)

    Jing-shu Wu; Min Xiao; Hu He; Shuan-jin Wang; Dong-mei Han; Yue-zhong Meng

    2011-01-01

    Using supported multi-component zinc dicarboxylate catalyst,poly(1,2-propylene carbonate-co-l,2-cyclohexylene carbonate) (PPCHC) was successfully synthesized from carbon dioxide (CO2) with propylene oxide (PO) and cyclohexene oxide (CHO).The conversion of epoxides dramatically increased up to 89.7% (yield:384.2 g of polymer per g of Zn) with increasing reaction temperature from 60℃ to 80℃.The optimized reaction temperature is 80℃.The chemical structure,the molecular weight,as well as thermal and mechanical properties of the resulting terpolymers were investigated extensively.When CHO feed content (mol%) is lower than 10%,the PPCHC terpolymers have number average molecular weight (Mn)ranging from 102 × 103 to 202 × 103 and molecular weight distribution (MWD) values ranging from 2.8 to 3.5.In contrast to poly(propylene carbonate) (PPC),the introduction of small amount of CHO leads to increase in the glass transition temperature from 38.0℃ to 42.6℃.Similarly,the mechanical strength of the synthesized terpolymer is greatly enhanced due to the incorporation of CHO.These improvements in mechanical and thermal properties are of importance for the practical application of PPC.

  6. Search for the Higgs boson in H->WW(*) decays in p anti-p collisions at S**(1/2) = 1.96-TEV

    CERN Document Server

    Abazov, V M; Abolins, M; Acharya, B S; Adams, M; Adams, T; Agelou, M; Agram, J L; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Andeen, T; Anderson, S; Andrieu, B; Arnoud, Y; Arov, M; Askew, A; Åsman, B; Assis-Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Balm, P W; Banerjee, P; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Beauceron, S; Begalli, M; Begel, M; Bellavance, A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Biscarat, C; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Blumenschein, U; Böhnlein, A; Boeriu, O; Bolton, T A; Borcherding, F; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Buchanan, N J; Buchholz, D; Bühler, M; Büscher, V; Burdin, S; Burke, S; Burnett, T H; Busato, E; Buszello, C P; Butler, J M; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chapin, D; Charles, F; Cheu, E; Cho, D K; Choi, S; Choudhary, B; Christiansen, T; Christofek, L; Claes, D; Clement, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Cothenet, A; Cousinou, M C; Cox, B; Crepe-Renaudin, S; Cutts, D; Da Motta, H; Das, M; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; De Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Dean, S; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dong, H; Doulas, S; Dudko, L V; Duflot, L; Dugad, S R; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Elvira, V D; Eno, S; Ermolov, P; Estrada, J; Evans, H; Evdokimov, A; Evdokimov, V N; Fast, J; Fatakia, S N; Feligioni, L; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fleck, I; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; García, C; García-Bellido, A; Gardner, J; Gavrilov, V; Gay, A; Gay, P; Gelé, D; Gelhaus, R; Genser, K; Gerber, C E; Gershtein, Yu; Gillberg, D; Ginther, G; Golling, T; Gollub, N; Gómez, B; Gounder, K; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Gris, P; Grivaz, J F; Grünendahl, S; Grünewald, M W; Gutíerrez, G; Gutíerrez, P; Haas, A; Hadley, N J; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, C; Han, L; Hanagaki, K; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Huang, J; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jain, V; Jakobs, K; Jarvis, C; Jenkins, A; Jesik, R; Johns, K; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J; Karmanov, D; Kasper, J; Katsanos, I; Kau, D; Kaur, R; Kehoe, R; Kermiche, S; Kesisoglou, S; Khanov, A; Kharchilava, A I; Kharzheev, Yu M; Kim, H; Kim, T J; Klima, B; Kohli, J M; Konrath, J P; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Kozminski, J; Kryemadhi, A; Krzywdzinski, S; Kulik, Y; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lager, S; Lahrichi, N; Landsberg, G L; Lazoflores, J; Le Bihan, A C; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Leonidopoulos, C; Lesne, V; Lévêque, J; Lewis, P; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linn, S L; Linnemann, J; Lipaev, V V; Lipton, R; Lobo, L; Lobodenko, A; Lokajícek, M; Lounis, A; Love, P; Lubatti, H J; Lueking, L; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Magnan, A M; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martens, M; Mattingly, S E K; McCarthy, R; McCroskey, R; Meder, D; Melnitchouk, A S; Mendes, A; Mendoza, L; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Miettinen, H; Mitrevski, J; Molina, J; Mondal, N K; Monk, J; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mundim, L; Mutaf, Y D; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Nelson, S; Neustroev, P; Nöding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; Nurse, E; O'Dell, V; O'Neil, D C; Oguri, V; Oliveira, N; Oshima, N; Oteroy-Garzon, G J; Padley, P; Parashar, N; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M; Pérez, E; Petroff, P; Petteni, M; Piegaia, R; Pleier, M A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M E; Pompos, A; Pope, B G; Prado da Silva, W L; Prosper, H B; Protopopescu, S D; Qian, J; Quadt, A; Quinn, B; Rani, K J; Ranjan, K; Rapidis, P A; Ratoff, P N; Reucroft, S; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F K; Robinson, S; Rodrigues, R F; Royon, C; Rubinov, P; Ruchti, R; Rud, V I; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A F S; Savage, G; Sawyer, L; Scanlon, T; Schaile, A D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schmitt, C; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sen-Gupta, S; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shephard, W D; Shivpuri, R K; Shpakov, D; Sidwell, R A; Simák, V; Sirotenko, V I; Skubic, P L; Slattery, P F; Smith, R P; Smolek, K; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Song, X; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Souza, M; Spurlock, B; Stanton, N R; Stark, J; Steele, J; Stevenson, K; Stolin, V; Stone, A; Stoyanova, D A; Strandberg, J; Strang, M A; Strauss, M; Ströhmer, R; Strom, D; Strovink, M; Stutte, L; Sumowidagdo, S; Sznajder, A; Talby, M; Tamburello, P; Taylor, W; Telford, P; Temple, J; Titov, M; Tomoto, M; Toole, T; Torborg, J; Towers, S; Trefzger, T; Trincaz-Duvoid, S; Tsybychev, D; Tuchming, B; Tully, C; Turcot, A S; Tuts, P M; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; Van den Berg, P J; Van Kooten, R; Van Leeuwen, W M; Varelas, N; Varnes, E W; Vartapetian, A H; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Séguier, F; Vlimant, J R; Von Törne, E; Vreeswijk, M; Vu-Anh, T; Wahl, H D; Wang, L; Warchol, J; Watts, G; Wayne, M; Weber, M; Weerts, H; Wermes, N; Wetstein, M; White, A; White, V; Wicke, D; Wijngaarden, D A; Wilson, G W; Wimpenny, S J; Wobisch, M; Womersley, J; Wood, D R; Wyatt, T R; Xie, Y; Xu, Q; Xuan, N; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yen, Y; Yip, K; Yoo, H D; Youn, S W; Yu, J; Yurkewicz, A; Zabi, A; Zatserklyaniy, A; Zdrazil, M; Zeitnitz, C; Zhang, D; Zhao, T; Zhao, Z; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zitoun, R; Zutshi, V; Zverev, E G

    2006-01-01

    We present a search for the standard model Higgs boson in H->WW(*), decays with ee, emu and mumu final states in p anti-p collisions at a center-of-mass energy of S**(1/2) = 1.96-TEV. The data, collected from April 2002 to June 2004 with the D0 detector, correspond to an integrated luminosity of 300 - 325 pb**(-1), depending on the final state. The number of events observed is consistent with the expectation from backgrounds. Limits from the combination of all three channels on the Higgs production cross section times branching ratio sigma*BR(H->WW(*) are presented.

  7. Preparing for Harvesting Radioisotopes from FRIB

    Energy Technology Data Exchange (ETDEWEB)

    Peaslee, Graham F. [Hope College, Holland, MI (United States); Lapi, Suzanne E. [Washington Univ., St. Louis, MO (United States)

    2015-02-02

    The Facility for Rare Isotope Beams (FRIB) is the next generation accelerator facility under construction at Michigan State University. FRIB will produce a wide variety of rare isotopes by a process called projectile fragmentation for a broad range of new experiments when it comes online in 2020. The accelerated rare isotope beams produced in this facility will be more intense than any current facility in the world - in many cases by more than 1000-fold. These beams will be available to the primary users of FRIB in order to do exciting new fundamental research with accelerated heavy ions. In the standard mode of operation, this will mean one radioisotope will be selected at a time for the user. However, the projectile fragmentation process also yields hundreds of other radioisotopes at these bombarding energies, and many of these rare isotopes are long-lived and could have practical applications in medicine, national security or the environment. This project developed new methods to collect these long-lived rare isotopes that are by-products of the standard FRIB operation. These isotopes are important to many areas of research, thus this project will have a broad impact in several scientific areas including medicine, environment and homeland security.

  8. INTRACORPOREAL HEAT DISSIPATION FROM A RADIOISOTOPE-POWERED ARTIFICIAL HEART.

    Science.gov (United States)

    Huffman, Fred N.; Hagen, Kenneth G.; Whalen, Robert L.; Fuqua, John M.; Norman, John C.

    1974-01-01

    The feasibility of radioisotope-fueled circulatory support systems depends on the ability of the body to dissipate the reject heat from the power source driving the blood pump as well as to tolerate chronic intracorporeal radiation. Our studies have focused on the use of the circulating blood as a heat sink. Initial in vivo heat transfer studies utilized straight tube heat exchangers (electrically and radioisotope energized) to replace a segment of the descending aorta. More recent studies have used a left ventricular assist pump as a blood-cooled heat exchanger. This approach minimizes trauma, does not increase the area of prosthetic interface with the blood, and minimizes system volume. Heat rejected from the thermal engine (vapor or gas cycle) is transported from the nuclear power source in the abdomen to the pump in the thoracic cavity via hydraulic lines. Adjacent tissue is protected from the fuel capsule temperature (900 to 1200 degrees F) by vacuum foil insulation and polyurethane foam. The in vivo thermal management problems have been studied using a simulated thermal system (STS) which approximates the heat rejection and thermal transport mechanisms of the nuclear circulatory support systems under development by NHLI. Electric heaters simulate the reject heat from the thermal engines. These studies have been essential in establishing the location, suspension, surgical procedures, and postoperative care for implanting prototype nuclear heart assist systems in calves. The pump has a thermal impedance of 0.12 degrees C/watt. Analysis of the STS data in terms of an electrical analog model implies a heat transfer coefficient of 4.7 x 10(-3) watt/cm(2) degrees C in the abdomen compared to a value of 14.9 x 10(-3) watt/cm(2) degrees C from the heat exchanger plenum into the diaphragm.

  9. Preliminary studies of Brazilian wood using different radioisotopic sources

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Gilberto; Silva, Leonardo Gondim de Andrade e, E-mail: gcarval@ipen.br, E-mail: ftgasilva@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Due to availability and particular features, wood was one of the first materials used by mankind with a wide variety of applications. It can be used as raw material for paper and cellulose manufacturing; in industries such as chemical, naval, furniture, sports goods, toys, and musical instrument; in building construction and in the distribution of electric energy. Wood has been widely researched; therefore, wood researchers know that several aspects such as temperature, latitude, longitude, altitude, sunlight, soil, and rainfall index interfere with the growth of trees. This behavior explains why average physical-chemical properties are important when wood is studied. The majority of researchers consider density to be the most important wood property because of its straight relationship with the physical and mechanical properties of wood. There are three types of wood density: basic, apparent and green. The apparent density was used here at 12% of moisture content. In this study, four different types of wood were used: 'freijo', 'jequetiba', 'muiracatiara' and 'ipe'. For wood density determination by non-conventional method, Am-241, Ba-133 and Cs-137 radioisotopic sources; a NaI scintillation detector and a counter were used. The results demonstrated this technique to be quick and accurate. By considering the nuclear parameters obtained as half value layers and linear absorption coefficients, Cs-137 radioisotopic source demonstrated to be the best option to be used for inspection of the physical integrity of electric wooden poles and live trees for future works. (author)

  10. Integro-differential equation analysis and radioisotope imaging systems. Research proposal. [Testing of radioisotope imaging system in phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Hart, H.

    1976-03-09

    Design modifications of a five-probe focusing collimator coincidence radioisotope scanning system are described. Clinical applications of the system were tested in phantoms using radioisotopes with short biological half-lives, including /sup 75/Se, /sup 192/Ir, /sup 43/K, /sup 130/I, and /sup 82/Br. Data processing methods are also described. (CH)

  11. Study of 16O(12C,α20Ne)α for the investigation of carbon-carbon fusion reaction via the Trojan Horse Method

    Science.gov (United States)

    Rapisarda, G. G.; Spitaleri, C.; Bordeanu, C.; Hons, Z.; Kiss, G. G.; La Cognata, M.; Mrazek, J.; Nita, C.; Pantelica, D.; Petrascu, H.; Pizzone, R. G.; Romano, S.; Szücs, T.; Trache, L.; Tumino, A.; Velisa, G.

    2016-04-01

    Carbon-carbon fusion reaction represents a nuclear process of great interest in astrophysics, since the carbon burning is connected with the third phase of massive stars (M > 8 M⊙) evolution. In spite of several experimental works, carbon-carbon cross section has been measured at energy still above the Gamow window moreover data at low energy present big uncertainty. In this paper we report the results about the study of the 16O(12C,α 20Ne)α reaction as a possible three-body process to investigate 12C(12C,α)20Ne at astrophysical energy via Trojan Horse Method (THM). This study represents the first step of a program of experiments aimed to measure the 12C+12C cross section at astrophysical energy using the THM.

  12. Formation of Polyhydroxyalkanoate Blends by Pseudomonas pseudoalcaligenes M1-2 from Various Carbon Sources

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Pseudomonas pseudoalcaligenes strain M1-2 isolated from oil-contaminated soil collected from an oilfield in northern China was found to be able to synthesize a blend of polyhydroxyalkanoates (PHAs) containing monomers of 3-hydroxybutyrate (C4), 3-hydroxyvalerate (C5), 3-hydroxyheptanoate (C7), 3-hydroxyoctanoate (C8), 3-hydroxynonanoate (C9), 3-hydroxydecanoate (C10) and 3-hydroxydodecanoate (C12) from various carbon sources.The hydroxyalkanoate (HA) monomer composition varied both quantitatively and qualitatively, depending on the carbon sources used.The presence of octanoate in substrates of myristic acid or tridecanoate promoted the synthesis of HB monomer in the blend.Concentration of octanoate was also found to significantly affect the PHB content in the blend.A PHA biosynthesis pathway in Pseudomonas pseudoalcaligens M1-2 was proposed.

  13. Crystal Morphology and 13Carbon/12Carbon Composition of Solid Oxalate in Cacti 1

    Science.gov (United States)

    Rivera, E. R.; Smith, B. N.

    1979-01-01

    Morphology, crystal structure, and carbon isotopic composition of calcium oxalate from representative species from the family Cactaceae were determined using scanning electron microscopy, x-ray diffraction, and isotope ratio mass spectrometry. Crystals from one species in the Opuntieae tribe of the Cactaceae were druses with acute points composed of the monohydrate form of calcium oxalate (whewellite). Crystals from three species in the Cereeae tribe were the dihydrate form of calcium oxalate (weddellite) forming druses made up of tetragonal and isodiametric crystallites. The oxalate was relatively enriched in 13C isotope (-7.3 to - 8.7 ‰) compared with woody fibers (-13.3 to 14.1 ‰) from the same plants. Images PMID:16661115

  14. Development of leakage monitoring system using radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. C.; Lee, D. S. [Seoil College, Seoul (Korea); Cho, Y. S. [Konyang University, Nonsan (Korea); Shin, S. K. [Sungkyunkwan Univ., Seoul (Korea)

    2000-04-01

    This study is to development the potable neutron back-scattering gauge for leakage and detecting liquid interface of an oil and liquid tank, using a radioisotopes. For this purpose, small sized, light weight potable gauge is to be designed as to develope neutron shielding mechanism, low power supply circuit, high voltage circuit, measurement circuit, and operating handle etc. The user will be able to set the duration of the time interval, the scale, the high voltage, the threshold, the channel window, the selection whether the data storage or not, the selection whether the scale, high voltage, threshold and window fix or not at any time. The counted pulse will be displayed with the numerical value and the line bar. The gauge will be able to connect to an IBM compatible PC via a serial port, power will be supplied by internal battery. 9 refs., 28 figs., 10 tabs. (Author)

  15. Radioisotope Power Systems Program: A Program Overview

    Science.gov (United States)

    Hamley, John A.

    2016-01-01

    NASA's Radioisotope Power Systems (RPS) Program continues to plan, mature research in energy conversion, and partners with the Department of Energy (DOE) to make RPS ready and available to support the exploration of the solar system in environments where the use of conventional solar or chemical power generation is impractical or impossible to meet potential future mission needs. Recent programs responsibilities include providing investment recommendations to NASA stakeholders on emerging thermoelectric and Stirling energy conversion technologies and insight on NASA investments at DOE in readying a generator for the Mars 2020 mission. This presentation provides an overview of the RPS Program content and status and the approach used to maintain the readiness of RPS to support potential future NASA missions.

  16. Energy Recovery Linacs for Commercial Radioisotope Production

    Energy Technology Data Exchange (ETDEWEB)

    Sy, Amy [Jefferson Lab, Newport News, VA; Krafft, Geoffrey A. [Jefferson Lab, Newport News, VA; Johnson, Rolland [Muons, Inc., Batavia, IL; Roberts, Tom; Boulware, Chase; Hollister, Jerry

    2015-09-01

    Photonuclear reactions with bremsstrahlung photon beams from electron linacs can generate radioisotopes of critical interest. An SRF Energy Recovery Linac (ERL) provides a path to a more diverse and reliable domestic supply of short-lived, high-value, high-demand isotopes in a more compact footprint and at a lower cost than those produced by conventional reactor or ion accelerator methods. Use of an ERL enables increased energy efficiency of the complex through energy recovery of the waste electron beam, high electron currents for high production yields, and reduced neutron production and shielding activation at beam dump components. Simulation studies using G4Beamline/GEANT4 and MCNP6 through MuSim, as well as other simulation codes, will design an ERL-based isotope production facility utilizing bremsstrahlung photon beams from an electron linac. Balancing the isotope production parameters versus energy recovery requirements will inform a choice of isotope production target for future experiments.

  17. Radioisotope scanning in inflammatory muscle disease

    Energy Technology Data Exchange (ETDEWEB)

    Brown, M.B.; Swift, T.R.; Spies, S.M.

    1976-06-01

    Fourteen whole-body rectilinear bone scans using technetium 99m-polyphosphate were done in nine patients with well-documented inflammatory myopathy (either polymyositis or dermatomyositis). In all nine patients the scans showed evidence of increased muscle labeling. Muscle uptake was markedly increased in one patient, moderately increased in two patients, and minimally increased in six patients. The degree of muscle labeling correlated with the severity of the muscle weakness at the time the scan was done. In four patients, who received high-dose corticosteroid treatment, muscle uptake was decreased following therapy. These findings suggest that radioisotope scanning may be useful in the diagnosis and management of patients with inflammatory muscle diseases.

  18. Recent progress in development of radioisotope production

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Byung Mok [HANARO Center, Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1998-10-01

    The Korea multipurpose research reactor, HANARO(Hi-flux Advanced Neutron Application Reactor) is designed and constructed to obtain high density neutron flux (max. 5x10{sup 14} n/cm{sup 2}{center_dot}sec) with relatively low thermal output (30 MW) in order to utilize for various studies such as fuel and material test, radioisotope production, neutron activation analysis, neutron beam experiment, neutron transmutation doping, etc. HANARO has 32 vertical channels (3 in-core, 4 out-core, 25 reflector) and 7 horizontal channels. KAERI has constructed 4 concrete hot cells for production of Co-60, Ir-192, etc. and 6 lead hot cells for production of medical RIs(I-131, Mo-99, etc.). Other 11 lead hot cells will be completed by Feb. 1998 for production of Sm-153, Dy-165, Ho-166, etc. Clean room facilities were installed for production of radiopharmaceuticals. (author)

  19. Vitamin B12: one carbon metabolism, fetal growth and programming for chronic disease.

    Science.gov (United States)

    Rush, E C; Katre, P; Yajnik, C S

    2014-01-01

    This review brings together human and animal studies and reviews that examine the possible role of maternal vitamin B12 (B12) on fetal growth and its programming for susceptibility to chronic disease. A selective literature review was undertaken to identify studies and reviews that investigate these issues, particularly in the context of a vegetarian diet that may be low in B12 and protein and high in carbohydrate. Evidence is accumulating that maternal B12 status influences fetal growth and development. Low maternal vitamin B12 status and protein intake are associated with increased risk of neural tube defect, low lean mass and excess adiposity, increased insulin resistance, impaired neurodevelopment and altered risk of cancer in the offspring. Vitamin B12 is a key nutrient associated with one carbon metabolic pathways related to substrate metabolism, synthesis and stability of nucleic acids and methylation of DNA which regulates gene expression. Understanding of factors regulating maternal-fetal one carbon metabolism and its role in fetal programming of non communicable diseases could help design effective interventions, starting with maternal nutrition before conception.

  20. Safety analysis report for medical radioisotope transport cask

    Energy Technology Data Exchange (ETDEWEB)

    Seo, K. S.; Ku, J. H.; Lee, J. C. [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-10-01

    KAERI has been producing radioisotopes for medical and industrial use and supplying them to radioisotope-using hospitals and industries. RI transport cask of A type package has been developed to transport medical radioisotopes from the HANARO to the hospitals. The safety analyses were performed under normal transport conditions in accordance with standards of transport regulations. As a results, it should be verified that the cask maintains the shielding and structural integrities under prescribed condition by the regulations. 8 refs., 20 figs., 7 tabs. (Author)

  1. Radioisotopes in sedimentary study of the Black Sea and Caspian Sea

    Science.gov (United States)

    Laptev, Gennady; Voitsekhovych, Oleg V.

    2013-04-01

    Natural archives, such as lake or marine sediment, are widely used in erosion/sedimentation, water quality, climate change and eutrophication study alongside with the retrospective reanalysis of contaminants fluxes (trace metals, organic pollutants or radionuclides). In order to "read" information stored in sediment sequences a chronostatigraphic method have been developed and used since 1950s which is based upon variation of activity of 210Pb over the sediment profile, natural radioisotope of Uranium decay series with half-life 22 years, and hence valid for the last 100-150 years of recent sedimentation history. The 210Pb chronology is prone to be validated by other time-markers, such as artificial radionuclides globally dispersed after the nuclear weapons tests of 1960s or major accidents on NPP (the Chernobyl accident of 1986 or latest on the Fukushima Daiichi in 2011). In the last decade an intensive study using sediment cores collected from shelf and deep-sea areas in the Black Sea and the Caspian Sea have been undertaken within the framework of a number of international research projects organized by IAEA and UNOPS-GEF and devoted to environmental problems of this enclosed, and therefore sensitive to environmental impact, marine systems. Elaborative analysis of the experimental data and sediment age calculation have been done by application of CRS and CIC dating models to unsupported 210Pb activity over the sediment profile. Measured in sediment 137Cs and 241Am clearly showed well resolved Bomb test and Chernobyl fallout peaks and were used as markers in order to corroborate radiometrically determined age of sediment. Geochronological reconstruction of the fallout radionuclides inventory, fluxes and accumulation rate in the sediment of the Black Sea and Caspian Sea by application of combined radiometric dating technique proved to be very consistent with the historical data of atmospheric fallout observations of that artificial radionuclides recorded worldwide

  2. Large N Approach to Kaon Decays and Mixing 28 Years Later: Delta I = 1/2 Rule, \\hat B_K and Delta M_K

    CERN Document Server

    Buras, Andrzej J; Bardeen, William A

    2014-01-01

    We review and update our results for K-> pipi decays and K^0-\\bar K^0 mixing obtained by us in the 1980s within an approach based on the dual representation of QCD as a theory of weakly interacting mesons for large N colours. In our analytic approach the dynamics behind the enhancement of ReA_0 and suppression of ReA_2, the so-called Delta I = 1/2 rule for K-> pi pi decays, has a simple structure: the usual octet enhancement through quark-gluon renormalization group evolution down to the scales O(1 GeV) is continued as a meson evolution down to zero momentum scales at which the factorization of hadronic matrix elements is at work. The inclusion of lowest-lying vector meson contributions in addition to the pseudoscalar ones and of Wilson coefficients in a momentum scheme improves significantly the matching between quark-gluon and meson evolutions. In particular, the anomalous dimension matrix governing the meson evolution exhibits the structure of the known anomalous dimension matrix in the quark-gluon evoluti...

  3. Synthesis of propylene carbonate from urea and 1,2-propanediol

    Institute of Scientific and Technical Information of China (English)

    Zhi Wen Gao; Shou Feng Wang; Chun Gu Xia

    2009-01-01

    The production of propylene carbonate(PC)from urea and 1,2-propanediol(PG)was investigated in a batch process.The catalytic performances of zinc chloride and magnesium chloride were investigated for this reaction system.The influences of various operation conditions on the PC yield were explored.In this work,MgCl2 and ZnCl2 showed the excellent catalytic activity toward PC synthesis,and the yields of propylene carbonate reached 96.5% and 92.4%,respectively.The optimum reaction conditions were as follows:ethanol/urea molar ratio of 4,catalyst concentration of 1.5%,reaction temperature of 160 ℃,reaction time of 3 h,respectively.The route from urea and 1,2-propanediol shows advantages,such as mild reaction condition and safe operation.The catalytic system is environmentally benign.

  4. Cascaded Thermoelectric Converters for Advanced Radioisotope Power Systems

    Science.gov (United States)

    El-Genk, Mohamed S.; Saber, Hamed H.

    2004-02-01

    Three Cascaded Thermoelectric Converters (CTCs) are optimized for potential use in Multi-Mission Advanced Radioisotope Power Systems (MM-ARPS) for electrical powers up to 1 kWe, or even higher, in support of 7-10 year missions. The peak efficiencies of these CTCs of 9.43% to 14.32% are 40% to 110% higher than that of SiGe in State-of-the-Art (SOA) Radioisotope Thermoelectric Generators (RTGs). Such high efficiencies would significantly reduce the amount of 238PuO2 fuel and the total system mass for a lower mission cost. Each CTC is comprised of a SiGe top unicouple that is thermally, but not electrically, coupled to a bottom unicouple with one of the following three choices of thermoelectric materials: (a) p-leg of TAGS-85 and n-leg of 2N-PbTe (b) p-leg of CeFe3.5Co0.5Sb12 and n-leg of CoSb3; and (c) segmented p-leg of CeFe3.5Co0.5Sb12 and Zn4Sb3 and n-leg of CoSb3. The length of the top and bottom unicouples is 10 mm, but the cross-sectional areas of the n- and p-legs of the unicouples are optimized for maximum efficiency operation. They vary with the thermal power inputs of 1, 2, and 3 Wth per SiGe unicouple, and the heat rejection temperature of 375 K, 475 K, and 575 K, from the bottom unicouple. Such geometrical optimization is at nominal hot shoe temperature of 1273 K for the SiGe unicouple and cold shoe temperature of either 780 K or 980 K, depending on the materials of the bottom unicouples. The hot shoe temperature of the bottom unicouples is 20 K lower than the cold shoe of the top SiGe unicouple, but the rate of heat input is the same as the rate of heat rejection from the top unicouple. The present results are conservative as they assume a contact resistance of 150 μΩ-cm2 per leg for the top and the bottom unicouples in the CTCs; however, decreasing this resistance to 50 μΩ-cm2 per leg could increase the current efficiency estimates by an additional 1 - 2 percentage points.

  5. Studies on 12 V substrate-integrated lead-carbon hybrid ultracapacitors

    Indian Academy of Sciences (India)

    A Banerjee; A K Shukla

    2015-05-01

    A cost-effective 12 V substrate-integrated lead-carbon hybrid ultracapacitor is developed and performance tested. These hybrid ultracapacitors employ flexible-graphite sheets as negative plate currentcollectors that are coated amperometrically with a thin layer of conducting polymer, namely poly-aniline to provide good adhesivity to activated-carbon layer. The positive plate of the hybrid ultracapacitors comprise conventional lead-sheet that is converted electrochemically into a substrate-integrated lead-dioxide electrode. 12 V substrate-integrated lead-carbon hybrid ultracapacitors both in absorbent-glass-mat and polymeric silicagel electrolyte configurations are fabricated and characterized. It is possible to realize 12 V configurations with capacitance values of ∼200 F and ∼300 F, energy densities of ∼1.9 Wh kg−1 and ∼2.5 Wh kg−1 and power densities of ∼2 kW kg−1 and ∼0.8 kW kg−1, respectively, having faradaic-efficiency values of ∼90 % with cycle-life in excess of 100,000 cycles. The effective cost of the mentioned hybrid ultracapacitors is estimated to be about ∼4 US$/Wh as compared to ∼20 US$/Wh for commercially available ultracapacitors.

  6. Thermal Model Predictions of Advanced Stirling Radioisotope Generator Performance

    Science.gov (United States)

    Wang, Xiao-Yen J.; Fabanich, William Anthony; Schmitz, Paul C.

    2014-01-01

    This presentation describes the capabilities of three-dimensional thermal power model of advanced stirling radioisotope generator (ASRG). The performance of the ASRG is presented for different scenario, such as Venus flyby with or without the auxiliary cooling system.

  7. Variable Conductance Heat Pipes for Radioisotope Stirling Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The overall program objective is to develop a high temperature variable conductance heat pipe (VCHP) backup radiator, and integrate it into a Stirling radioisotope...

  8. Advanced Radiative Emitters for Radioisotope Thermophotovoltaic Power Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Radioisotope Power Systems (RPS) are critical for future flagship exploration missions in space and on planetary surfaces. Small improvements in the RPS performance,...

  9. A historical perspective on radioisotopic tracers in metabolism and biochemistry.

    Science.gov (United States)

    Lappin, Graham

    2015-01-01

    Radioisotopes are used routinely in the modern laboratory to trace and quantify a myriad of biochemical processes. The technique has a captivating history peppered with groundbreaking science and with more than its share of Nobel Prizes. The discovery of radioactivity at the end of the 19th century paved the way to understanding atomic structure and quickly led to the use of radioisotopes to trace the fate of molecules as they flowed through complex organic life. The 1940s saw the first radiotracer studies using homemade instrumentation and analytical techniques such as paper chromatography. This article follows the history of radioisotopic tracers from meager beginnings, through to the most recent applications. The author hopes that those researchers involved in radioisotopic tracer studies today will pause to remember the origins of the technique and those who pioneered this fascinating science.

  10. Annual Technical Progress Report of Radioisotope Power Systems Materials Production and Technology Program Tasks for October 1, 2006 Through September 30, 2007

    Energy Technology Data Exchange (ETDEWEB)

    King, James F [ORNL

    2008-04-01

    The Office of Radioisotope Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Radioisotope Power Systems for fiscal year (FY) 2007. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.

  11. Efficiency of Pm-147 direct charge radioisotope battery

    Energy Technology Data Exchange (ETDEWEB)

    Kavetskiy, A.; Yakubova, G.; Yousaf, S.M. [TRACE Photonics Inc, 1680 West Polk Avenue, Charleston, IL 61920 (United States); Bower, K., E-mail: kbower@tracephotonics.co [TRACE Photonics Inc, 1680 West Polk Avenue, Charleston, IL 61920 (United States); Robertson, J.D.; Garnov, A. [Department of Chemistry and University of Missouri Research Reactor, 1513 Research Park Drive, Columbia, MO 65211 (United States)

    2011-05-15

    A theoretical analysis is presented here of the efficiency of direct charge radioisotope batteries based on the efficiency of the radioactive source, the system geometry, electrostatic repulsion of beta particles from the collector, the secondary electron emission, and backscattered beta particles from the collector. Efficiency of various design batteries using Pm-147 sources was experimentally measured and found to be in good agreement with calculations. The present approach can be used for predicting the efficiency for different designs of direct charge radioisotope batteries.

  12. Final State Interactions in $K\\to\\pi\\pi$ Decays: $\\Delta I=1/2$ Rule vs. $\\varepsilon^\\prime/\\varepsilon$

    CERN Document Server

    Buras, Andrzej J

    2016-01-01

    Dispersive effects from strong $\\pi\\pi$ rescattering in the final state (FSI) of weak $K\\to\\pi\\pi$ decays are revisited with the goal to have a global view on their {\\it relative} importance for the $\\Delta I=1/2$ rule and the ratio $\\varepsilon^\\prime/\\varepsilon$ in the Standard Model (SM). We point out that this goal cannot be reached within a pure effective (meson) field approach like chiral perturbation theory in which the dominant current-current operators governing the $\\Delta I=1/2$ rule and the dominant density-density (four-quark) operators governing $\\varepsilon^\\prime/\\varepsilon$ cannot be disentangled from each other. But in the context of a dual QCD approach, which includes both long distance dynamics and the UV completion, that is QCD at short distance scales, such a distinction is possible. We find then that beyond the strict large $N$ limit, $N$ being the number of colours, FSI are likely to be important for the $\\Delta I=1/2$ rule but much less relevant for $\\varepsilon^\\prime/\\varepsilon$....

  13. Study of removal of Direct Yellow 12 by cadmium oxide nanowires loaded on activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Ghaedi, Mehrorang, E-mail: m_ghaedi@mail.yu.ac.ir [Chemistry Department, Yasouj University Yasouj 75914-35 (Iran, Islamic Republic of); Sadeghian, Batuol [Chemistry Department, Yasouj University Yasouj 75914-35 (Iran, Islamic Republic of); Kokhdan, Syamak Nasiri, E-mail: syamak.nasiri@yahoo.com [Chemistry Department, Yasouj University Yasouj 75914-35 (Iran, Islamic Republic of); Pebdani, Arezou Amiri [Chemistry Department, Yasouj University Yasouj 75914-35 (Iran, Islamic Republic of); Sahraei, Reza; Daneshfar, Ali; Mihandoost, Asma [Department of Chemistry, University of Ilam, P.O. Box: 65315-516, Ilam (Iran, Islamic Republic of)

    2013-05-01

    In this research, cadmium oxide nanowires loaded on activated carbon (CdO-NW-AC) has been synthesized by a simple procedure and characterized by different techniques such as XRD, SEM and UV–vis spectrometry. This new adsorbent has been efficiently utilized for the removal of the Direct Yellow 12 (DY-12) from wastewater. To obtain maximum DY-12 removal efficiency, the influences of variables such as pH, DY-12 concentration, amount of CdO-NW-AC, contact time, and temperature have been examined and optimized in a batch method. Following the variable optimization, the experimental equilibrium data (at different concentration of DY-12) was fitted to conventional isotherm models such as Langmuir, Freundlich and Tempkin. The applicability of each method is based on the R{sup 2} and error analysis for each model. It was found that the experimental equilibrium data well fitted to the Langmuir isotherm model. The dependency of removal process to time and the experimental data follow second order kinetic model with involvement of intraparticle diffusion model. The negative value of Gibbs's free energy and positive value of adsorption enthalpy show the spontaneous and endothermic nature of adsorption process. - Graphical abstract: Typical FE-SEM image of the CdO nanowires. Highlights: ► Cadmium oxide nanowires loaded on activated carbon was utilized as an adsorbent. ► It was used for the removal of Direct Yellow 12 from aqueous solutions. ► The adsorption of Direct Yellow 12 on this adsorbent is endothermic in nature. ► The adsorption equilibrium data was well described by the Langmuir isotherm model.

  14. Spectrochemical studies with {beta}-emitting radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Chesta, Miguel A.; Plivelic, Tomas S.; Mainardi, Raul T. [Cordoba Univ. Nacional (Argentina). Facultad de Matematica, Atronomia y Fisica

    1997-12-01

    Electrons emitted by {sup 90} Sr radioactive source and positrons from a {sup 22} Na source were used to produce ionizations in the constituents of a sample. The sources have similar energy spectra and this allowed us to compare the characteristic radiation emission efficiencies. The new proposed experimental set up for radioisotope excited x-ray fluorescence analysis (XRFA) is of a transparent source type and provides at least a ten times increase in the intensity of characteristic x-rays emitted by the sample as compared with a standard set up in XRFA. It is shown that this fact, together with the relatively high energy of the beta particles, make it possible to carry out a mirror elemental analysis in a few minutes using low intensity radioactive sources (no special handling license). Preliminary experimental results are shown using both electrons and positrons impinging on pure and composed samples and simple analytical expressions are provided for the characteristic radiation intensity as detected by an HPGe detector. (author). 7 refs., 4 figs.

  15. Use of copper radioisotopes in investigating disorders of copper metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Camakaris, J.; Voskoboinik, I.; Brooks, H.; Greenough, M. [University of Melbourne, Parkville, VIC (Australia). Department of Genetics; Smith, S. [Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW (Australia). Radiopharmaceuticals Division; Mercer, J. [Deakin University, Rusden Campus, Clayton, VIC (Australia). Centre of Cellular and Molecular Biology

    1998-12-31

    Full text: Copper is an essential trace element for life as a number of vital enzymes require it. Copper deficiency can lead to neurological disorders, osteoporosis and weakening of arteries. However Cu is also highly toxic and homeostatic mechanisms have evolved to maintain Cu at levels which satisfy requirements but do not cause toxicity. Toxicity is mediated by the oxidative capacity of Cu and its ability to generate toxic free radicals. There are several acquired and inherited diseases due to either Cu toxicity or Cu deficiency. The study of these diseases facilitates identification of genes and proteins involved in copper homeostasis, and this in turn will provide rational therapeutic approaches. Our studies have focused on Menkes disease in humans which is an inherited and usually lethal copper deficiency. Using copper radioisotopes {sup 64}Cu (t 1/2 = 12.8 hr) and {sup 67}Cu (t 1/2 = 61 hr) we have studied the protein which is mutated in Menkes disease. This is a transmembrane copper pump which is responsible for absorption of copper into the body and also functions to pump out excess Cu from cells when Cu is elevated. It is therefore a vital component of normal Cu homeostasis. We have provided the first biochemical evidence that the Menkes protein functions as a P-type ATPase Cu pump (Voskoboinik et al., FEBS Letters, in press) and these data will be discussed. The assay involved pumping of radiocopper into purified membrane vesicles. Furthermore we have transfected normal and mutant Menkes genes into cells and are carrying out structure-function studies. We are also studying the role of amyloid precursor protein (APP) as a Cu transport protein in order to determine how Cu regulates this protein and its cleavage products. These studies will provide vital information on the relationship between Cu and APP and processes which lead to Alzheimers disease

  16. Studies of copper transport in mammalian cells using copper radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Camakaris, J.; Voskoboinik, I.; Brooks, H.; Greenough, M. [University of Melbourne, Parkville, VIC (Australia). Department of Genetics; Smith, S. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia). Radiopharmaceuticals Division; Mercer, J. [Deakin University, Clayton, VIC (Australia). Centre of Cellular and Molecular Biology

    1998-12-31

    The trace element copper poses a major problem for all organisms. It is essential as a number of vital enzymes require it. Copper deficiency can lead to neurological disorders, osteoporosis and weakening of arteries. However Cu is also highly toxic and homeostatic mechanisms have evolved to maintain Cu at levels which satisfy requirements but do not cause toxicity. Toxicity is mediated by the oxidative capacity of Cu and its ability to generate toxic free radicals. There are several acquired and inherited diseases due to either Cu toxicity or Cu deficiency. The study of these diseases facilitates identification of genes and proteins involved in copper homeostasis, and this in turn will provide rational therapeutic approaches. Using the copper radioisotopes {sup 64}Cu (t1/2 = 12.8 hr) and {sup 67}Cu (t1/2 = 61 hr) we have developed a number of systems for studying copper transport in mammalian cells. These include investigation of copper uptake, copper efflux and ligand blot assays for Cu-binding proteins. Our studies have focused on Menkes disease which is an inherited and usually lethal copper deficiency disorder in humans. We have demonstrated that the Menkes protein is directly involved as a copper efflux pump in mammalian cells. Using cells overexpressing the Menkes protein we have provided the first biochemical evidence that this functions as a Cu translocating (across the membrane) P-type ATPase (Voskoboinik et al., FEBS Letters, in press). These studies were carried out using purified plasma membrane vesicles. We are now carrying out structure- function studies on this protein using targeted mutations and assaying using the radiocopper vesicle assay. Recently we have commenced studies on the role of amyloid precursor protein (APP) in copper transport and relationship of this to Alzheimers disease

  17. Coated particle fuel for radioisotope power systems (RPSs) and radioisotope heater units (RHUs)

    Science.gov (United States)

    Sholtis, Joseph A.; Lipinski, Ronald J.; El-Genk, Mohamed S.

    1999-01-01

    Coated particle fuel offers great promise for advanced radioisotope power systems (RPSs) and radioisotope heater units (RHUs) being pursued for future U.S. solar system exploration missions. Potential benefits of this fuel include improved design flexibility and materials compatibility, enhanced safety and performance, and reduced specific mass and volume. This paper describes and discusses coated particle fuel, with emphasis on its applicability, attributes, and potential benefits to future RPSs and RHUs. Additionally, this paper identifies further analyses and verification testing that should be conducted before a commitment is made to fully develop this fuel. Efforts to date indicate there is every reason to believe that the potential benefits of coated particle fuel to future RPSs and RHUs can be demonstrated with a modest, phased analytical and verification test effort. Thus, developmental risk appears minimal, while the potential benefits are substantial. If coated particle fuel is pursued and ultimately developed successfully, it could revolutionize the design and space use of future RPSs and RHUs.

  18. Formation of carburized layer structure with reverted austenite on low-carbon martensitic steel 12Kh2G2NMFT

    Science.gov (United States)

    Ivanov, A. S.; Bogdanova, M. V.

    2013-03-01

    The structure of surface layer in low-carbon martensitic steel 12Kh2G2NMFT obtained by carburizing followed by high-temperature tempering and quenching from the intercritical temperature range is investigated.

  19. Use of U and Th Decay-Series Disequilibrium to Characterize Geothermal Systems: An Example from the Coso Geothermal System

    Science.gov (United States)

    Leslie, B. W.; Hammond, D.

    2007-12-01

    Uranium and thorium decay series isotopes were measured in fluids and solids in the Coso geothermal system to assess the utility and constrain the limitations of the radioisotopic approach to the investigation of rock-water interaction. Fluid radioisotope measurements indicate substantial kilometer-scale variability in chemistry. Between 1988 and 1990, radium isotope activity ratios indicate temporal variability, which is exhibited by apparent mixing relationships observed as a function of time for single wells. Activity ratios of Ra-224/Ra-226 and Ra- 228/Ra-226, and the processes that contribute and remove these radionuclide to and from the fluids, constrain residence times of fluids and may help constrain fluid velocities in the geothermal system. Activity ratios of Ra- 224/Ra-226 > ten were measured. In groundwater and geothermal systems ratios of Ra-224/Ra-226 > ten are limited to zones of thermal upwelling or very young (days to weeks) waters in mountainous areas. Rn-222 results indicate that radon is also an effective tracer for steam velocities within the geothermal system. Analysis of carbon dioxide and Rn-222 data indicates that the residence time of steam (time since separation from the liquid) is short (probably less than four days). Estimates of fluid velocities derived from Rn-222 and radium isotopic measurements are within an order of magnitude of velocities derived from a fluorescein tracer test. Both Rn-222 and Ra-224 activities are higher in single-phase fluids in the northwest as compared to the southeast, indicating a higher rock-surface-area/water-volume ratio in the northwest. Thus, measurements of short-lived radioisotopes and gaseous phase constituents can constrain processes and characteristics of geothermal systems that are usually difficult to constrain (e.g., surface area/volume, residence times). The NRC staff views expressed herein are preliminary and do not constitute a final judgment or determination of the matters addressed or of

  20. Studies on the production and application of radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Han, Hyon Soo; Park, K. B.; Kim, J. R.; Yoon, B. M.; Bang, H. S.; Shin, B. C.; Cho, W. K.; Park, U. J.; Park, C. D.; Lee, Y. G.; Suh, C. H.; Shin, H. Y.; Kim, D. S.; Hong, S. B.; Jun, S. S.; Min, E. S.; Jang, K. D.; Kim, J. K.; Kim, S. J.; Yang, S. Y.; Yang, S. H.; Chun, K. J.; Kang, H. Y.; Suh, K. S.; Goo, J. H.; Chung, S. H.; Lee, J. C.; Choi, J. L.; Lee, H. Y.; Bang, K. S.

    1997-09-01

    To produce radioisotopes utilizing the research reactor `HANARO`, development of RI production process, target fabrication, preparation of devices and tools for RI process, preparation of production facility for radiopharmaceuticals, test production for the established process, etc. have been carried out, respectively. Production processes for various kinds of radionuclides were developed and the settled methods were applied to test production using `HANARO`. The results of developed process are as follows: (1) I-131 dry distillation method. (2) Large scale production of Ir-192 sources (3) P-32 production process by distillation under reduced pressure (4) Cr-51 production process using enriched target. To irradiate the target for RI production in `HANARO`, target for neutron irradiation, loading/unloading devices, working table in service pool, remote handling tools, shield cask for irradiated target transfer, etc. were designed and fabricated. The function test of prepared targets and the safety analysis of shielding casks were carried out. License for practical use of the prepared casks were obtained from Ministry of Science and Technology. For production of medical radioisotopes, their production facilities were designed in detail and were installed in RIPF (Radioisotope Production Facility), with full reflection of the basic concept of the good manufacturing practice for radiopharmaceuticals. The constructed GMP facilities have started to be operated after authorization since Jun., 1997. Results of this study will be applied to mass production of radioisotopes in `HANARO` and are to contribute the advance of domestic medicine and industry related to radioisotopes. (author). 7 refs., 7 tabs., 4 figs.

  1. Operations of a Radioisotope-based Propulsion System Enabling CubeSat Exploration of the Outer Planets

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Steven Howe; Nathan Jerred; Troy Howe; Adarsh Rajguru

    2014-05-01

    Exploration to the outer planets is an ongoing endeavor but in the current economical environment, cost reduction is the forefront of all concern. The success of small satellites such as CubeSats launched to Near-Earth Orbit has lead to examine their potential use to achieve cheaper science for deep space applications. However, to achieve lower cost missions; hardware, launch and operations costs must be minimized. Additionally, as we push towards smaller exploration beds with relative limited power sources, allowing for adequate communication back to Earth is imperative. Researchers at the Center for Space Nuclear Research are developing the potential of utilizing an advanced, radioisotope-based system. This system will be capable of providing both the propulsion power needed to reach the destination and the additional requirements needed to maintain communication while at location. Presented here are a basic trajectory analysis, communication link budget and concept of operations of a dual-mode (thermal and electric) radioisotope-based propulsion system, for a proposed mission to Enceladus (Saturnian icy moon) using a 6U CubeSat payload. The radioisotope system being proposed will be the integration of three sub-systems working together to achieve the overall mission. At the core of the system, stored thermal energy from radioisotope decay is transferred to a passing propellant to achieve high thrust – useful for quick orbital maneuvering. An auxiliary closed-loop Brayton cycle can be operated in parallel to the thrusting mode to provide short bursts of high power for high data-rate communications back to Earth. Additionally, a thermal photovoltaic (TPV) energy conversion system will use radiation heat losses from the core. This in turn can provide the electrical energy needed to utilize the efficiency of ion propulsion to achieve quick interplanetary transit times. The intelligent operation to handle all functions of this system under optimized conditions adds

  2. Weak Decay of Hypernuclei

    CERN Document Server

    Alberico, W M

    2004-01-01

    The focus of these Lectures is on the weak decay modes of hypernuclei, with special attention to Lambda-hypernuclei. The subject involves many fields of modern theoretical and experimental physics, from nuclear structure to the fundamental constituents of matter and their interactions. The various weak decay modes of Lambda-hypernuclei are described: the mesonic mode and the non-mesonic ones. The latter are the dominant decay channels of medium--heavy hypernuclei, where, on the contrary, the mesonic decay is disfavoured by Pauli blocking effect on the outgoing nucleon. In particular, one can distinguish between one-body and two-body induced decays. Theoretical models employed to evaluate the (partial and total) decay widths of hypernuclei are illustrated, and their results compared with existing experimental data. Open problems and recent achievements are extensively discussed, in particular the determination of the ratio Gamma_n/Gamma_p, possible tests of the Delta I=1/2 rule in non-mesonic decays and the pu...

  3. Search for narrow resonances decaying to dijets in pp collisions at $\\sqrt{s}=13~\\mathrm{TeV}$ using $12.9~\\mathrm{fb}^{-1}$

    CERN Document Server

    CMS Collaboration

    2016-01-01

    A search is presented for narrow resonances decaying to dijet final states in proton-proton collisions at $\\sqrt{s}=13$ TeV from an integrated luminosity of 12.9 fb$^{-1}$. Results are presented for two searches. A low-mass search, for a resonance mass between 0.6 TeV and 1.6 TeV, is performed using dijets that are reconstructed from calorimeter information in the high-level trigger. A high-mass search, for resonances with mass above 1.6 TeV, is performed using dijets reconstructed with the particle flow algorithm from the normal reconstruction chain. The pseudorapidity separation of the two jets is required to satisfy $|\\Delta\\eta_{\\text{jj}}|<1.3$ with each jet inside the region $|\\eta| < 2.5$. The spectra are well described by a smooth parameterization and no significant evidence for new particle production is observed. Upper limits at 95\\% confidence level are reported on the production cross section times branching ratio to dijets times acceptance of the $|\\Delta\\eta_{\\text{jj}}|$ and $|\\eta|$ cuts...

  4. Hair radioactivity as a measure of exposure to radioisotopes

    Science.gov (United States)

    Strain, W. H.; Pories, W. J.; Fratianne, R. B.; Flynn, A.

    1972-01-01

    Since many radioisotopes accumulate in hair, this tropism was investigated by comparing the radioactivity of shaved with plucked hair collected from rats at various time intervals up to 24 hrs after intravenous injection of the ecologically important radioisotopes, iodine-131, manganese-54, strontium-85, and zinc-65. The plucked hair includes the hair follicles where biochemical transformations are taking place. The data indicate a slight surge of each radioisotpe into the hair immediately after injection, a variation of content of each radionuclide in the hair, and a greater accumulation of radioactivity in plucked than in shaved hair. These results have application not only to hair as a measure of exposure to radioisotopes, but also to tissue damage and repair at the hair follicle.

  5. Investigation of Miniaturized Radioisotope Thermionic Power Generation for General Use

    Science.gov (United States)

    Duzik, Adam J.; Choi, Sang H.

    2016-01-01

    Radioisotope thermoelectric generators (RTGs) running off the radioisotope Pu238 are the current standard in deep space probe power supplies. While reliable, these generators are very inefficient, operating at only approx.7% efficiency. As an alternative, more efficient radioisotope thermionic emission generators (RTIGs) are being explored. Like RTGs, current RTIGs concepts use exotic materials for the emitter, limiting applicability to space and other niche applications. The high demand for long-lasting mobile power sources would be satisfied if RTIGs could be produced inexpensively. This work focuses on exposing several common materials, such as Al, stainless steel, W, Si, and Cu, to elevated temperatures under vacuum to determine the efficiency of each material as inexpensive replacements for thermoelectric materials.

  6. Procurement of a fully licensed radioisotope thermoelectric generator transportation system

    Science.gov (United States)

    Adkins, Harold E.; Bearden, Thomas E.

    1991-01-01

    A fully licensed transportation system for Radioisotope Thermoelectric Generators and Light-Weight Radioisotope Heater Units is currently being designed and built. The system will comply with all applicable U.S. Department of Transportation regulations without the use of a ``DOE Alternative.'' The U.S. Department of Transportation has special ``double containment'' requirements for plutonium. The system packaging uses a doubly contained ``bell jar'' concept. A refrigerated trailer is used for cooling the high-heat payloads. The same packaging is used for both high- and low-heat payloads. The system is scheduled to be available for use by mid-1992.

  7. Ablation response testing of simulated radioisotope power supplies

    Science.gov (United States)

    Lutz, Steven A.; Chan, Chris C.

    1994-05-01

    Results of an experimental program to assess the aerothermal ablation response of simulated radioisotope power supplies are presented. Full-scale general purpose heat source, graphite impact shell, and lightweight radioisotope heater unit test articles are all tested without nuclear fuel in simulated reentry environments. Convective stagnation heating, stagnation pressure, stagnation surface temperature, surface recession profile, and weight loss measurements are obtained for diffusion-limited and sublimation ablation conditions. The recession profile and weight loss measurements show an effect of surface features on the stagnation face. The surface features alter the local heating which in turn affects the local ablation.

  8. KAERI charged particle cross section library for radioisotope production

    CERN Document Server

    Chang, J H; Kim, D H; Lee, Y O; Zhuang, Y X

    2001-01-01

    This report summarized information and figures describing the 'KAERI Charged Particle Cross Section Library for Radioisotope production' The library contains proton-, deutron-, He-3-, and alpha-induced monitor cross sections, and gamma- and positron-emitter production cross sections. Experimental data and evaluation methods are described, and the evaluated cross sections are compared with those of the IAEA, MENDL, and LA150. The library has cross sections and emission spectra suitable for the transport analysis in the design of radioisotope production system, and are available at http://atom.kaeri.re.kr/ in ENDF-6 format.

  9. Synthesis and characterization of radioisotope nanospheres containing two gamma emitters.

    Science.gov (United States)

    Jung, Jin-Hyuck; Jung, Sung-Hee; Kim, Sang-Ho; Choi, Seong-Ho

    2012-12-01

    Silica-coated gold-silver alloy nanospheres prepared by Stöber's method were irradiated in a nuclear reactor to prepare radioisotope nanospheres for use as radiotracers. The radioisotope nanospheres included two gamma nuclides: (i) Au-198, emitting major photons with 0.412 MeV and (ii) Ag-108, emitting photons with 0.434 and 0.633 MeV. The nanospheres shell and core diameters were 100-112 nm and 20-50 nm, respectively, depending on their preparation. The gamma-emitting nanospheres could be used as tracers in high-temperature petrochemical and refinery processes in which conventional organic radioactive labels will decompose.

  10. Recoil-Implantation Of Multiple Radioisotopes Towards Wear Rate Measurements And Particle Tracing In Prosthetic Joints

    Science.gov (United States)

    Warner, Jacob A.; Smith, Paul N.; Scarvell, Jennifer M.; Gladkis, Laura; Timmers, Heiko

    2011-06-01

    This study demonstrates a new method of radioisotope labeling of ultra-high molecular weight polyethylene inserts in prosthetic joints for wear studies. The radioisotopes 97Ru, 100Pd, 100Rh, and 101mRh are produced in fusion evaporation reactions induced by 12C ions in a 92Zr target foil. The fusion products recoil-implant into ultra-high molecular weight polyethylene plugs, machined to fit into the surface of the inserts. During laboratory simulations of the joint motion, a wear rate of the labeled polyethylene may be measured and the pathways of wear debris particles can be traced by detecting characteristic gamma-rays. The concentration profiles of the radioisotopes extend effectively uniformly from the polyethylene surface to a depth of about 4 μm. The multiplicity of labeling and the use of several gamma-ray lines aids with avoiding systematic measurement uncertainties. Two polyethylene plugs were labeled and one was fitted into the surface of the tibial insert of a knee prosthesis, which had been worn in. Actuation over close to 100,000 cycles with a 900 N axial load and a 24° flexion angle removed (14±1)% of the gamma-ray activity from the plug. Most of this activity dispersed into the serum lubricant identifying this as the important debris pathway. Less than 1% activity was transferred to the femoral component of the prosthesis and the measured activity on the tibial tray was insignificant. Assuming uniform wear across the superior surface of the insert, a wear rate of (12±3) mm3/Megacycle was determined. This is consistent with wear rate measurements under similar conditions using other techniques.

  11. Convivial Decay

    DEFF Research Database (Denmark)

    Cohn, Marisa

    2016-01-01

    in the life of infrastructure we can observe common issues associated with aging infrastructures – hardware’s material decay, programming languages and software tools reaching end of support, obsolete managerial methodologies, etc. Such a case of infrastructural decay reveals how work of infrastructure...... maintenance may reach the limits of repair and shift from repair-as-sustaining into a mode of repair- into-decay, actively working towards the end-of-life. What this reveals is that, rather than infrastructural decay being a natural by-product of time’s passing, there is active work that goes into producing......This paper discusses the empirical case of an aging and obsolescent infrastructure supporting a space science mission that is currently approaching a known end. Such a case contributes to our understanding of the degrading path at the end-of-life of an infrastructure. During this later stage...

  12. 78 FR 1848 - Plutonium-238 Production for Radioisotope Power Systems for National Aeronautics and Space...

    Science.gov (United States)

    2013-01-09

    ... Plutonium-238 Production for Radioisotope Power Systems for National Aeronautics and Space Administration...-238 (Pu-238) for radioisotope power systems (RPSs) to support the National Aeronautics and Space... Radioisotope Power Systems (Draft Consolidation EIS) in 2005 to consolidate the nuclear operations related...

  13. Current status of the production and research of radioisotopes in JAERI

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hidetake [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Sekine, Toshiaki [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2000-10-01

    Status of the radioisotope production and application in Japan is described, emphasizing that of reactor-produced radioisotopes for medicine. Some new application of reactor-produced radioisotopes to therapy are discussed together with those of positron emitters for medicine and plant physiology. (author)

  14. Proton Decay

    OpenAIRE

    Hikosaka, Koki

    2002-01-01

    We discuss the status of supersymmetric grand unified theories [SUSY GUTs] with regards to the observation of proton decay. In this talk we focus on SUSY GUTs in 4 dimensions. We outline the major theoretical uncertainties present in the calculation of the proton lifetime and then present our best estimate of an absolute upper bound on the predicted proton lifetime. Towards the end, we consider some new results in higher dimensional GUTs and the ramifications for proton decay.

  15. Decay of Hoyle state

    Indian Academy of Sciences (India)

    S Bhattacharya; T K Rana; C Bhattacharya; S Kundu; K Banerjee; T K Ghosh; G Mukherjee; R Pandey; P Roy

    2014-11-01

    The prediction of Hoyle state was necessitated to explain the abundance of carbon, which is crucial for the existence of life on Earth and is the stepping stone for understanding the abundance of other heavier elements. After the experimental confirmation of its existence, soon it was realized that the Hoyle state was `different’ from other excited states of carbon, which led to intense theoretical and experimental activities over the past few decades to understand its structure. In recent times, precision, high statistics experiments on the decay of Hoyle state have been performed at the Variable Energy Cyclotron Centre, to determine the quantitative contributions of various direct 3 decay mechanisms of the Hoyle state. The present results have been critically compared with those obtained in other recent experiments and their implications have been discussed.

  16. Stable carbon isotope fractionation in the UV photolysis of CFC-11 and CFC-12

    Directory of Open Access Journals (Sweden)

    A. Zuiderweg

    2011-12-01

    Full Text Available The chlorofluorocarbons CFC-11 (CCl3F and CFC-12 (CCl2F2 are stable atmospheric compounds that are produced at the earth's surface, but removed only at high altitudes in the stratosphere, where their removal liberates atomic chlorine that then catalytically destroys stratospheric ozone. For such long-lived compounds, isotope effects in the stratospheric removal reactions have a large effect on their global isotope budgets. We have determined the photolytic isotope fractionation for stable carbon isotopes of CFC-11 and CFC-12 in laboratory experiments. 13C/12C isotope fractionations (ϵ range from (−23.7 ± 0.9 to (−17.5 ± 0.4‰ for CFC-11 and (−69.2 ± 3.4 to (−49.4 ± 2.3‰ for CFC-12 between 203 and 288 K, a temperature range relevant to conditions in the troposphere and stratosphere. These results suggest that CFCs should become strongly enriched in 13C with decreasing mixing ratio in the stratosphere, similar to what has been recently observed for CFC chlorine isotopes. In conjunction with the strong variations in CFC emissions before and after the Montréal Protocol, the stratospheric enrichments should also lead to a significant temporal increase in the 13C content of the CFCs at the surface over the past decades, which should be recorded in atmospheric air archives such as firn air.

  17. Progress in the Use of Isotopes: The Atomic Triad - Reactors, Radioisotopes and Radiation

    Science.gov (United States)

    Libby, W. F.

    1958-08-04

    Recent years have seen a substantial growth in the use of isotopes in medicine, agriculture, and industry: up to the minute information on the production and use of isotopes in the U.S. is presented. The application of radioisotopes to industrial processes and manufacturing operations has expanded more rapidly than any one except its most ardent advocates expected. New uses and new users are numerous. The adoption by industry of low level counting techniques which make possible the use of carbon-14 and tritium in the control of industrial processes and in certain exploratory and research problems is perhaps most promising of current developments. The latest information on savings to industry will be presented. The medical application of isotopes has continued to develop at a rapid pace. The current trend appears to be in the direction of improvements in technique and the substitution of more effective isotopes for those presently in use. Potential and actual benefits accruing from the use of isotopes in agriculture are reviewed. The various methods of production of radioisotopes are discussed. Not only the present methods but also interesting new possibilities are covered. Although isotopes are but one of the many peaceful uses of the atom, it is the first to pay its way. (auth)

  18. High radio-isotope uptakes in patients with hypothyroidism

    Energy Technology Data Exchange (ETDEWEB)

    Wing, J.; Kalk, W.J.; Ganda, C. (University of the Witwatersrand, Johannesburg (South Africa). Dept. of Medicine)

    1982-12-04

    Hypothyroidism is usually associated with a low radio-isotope uptake by the thyriod gland. We report 8 cases of Hashimoto's thyroiditis with clinical and biochemical hypothyroidism and with borderline high or overtly increased technetium-99m pertechnetate and/or iodine-131 uptakes.

  19. Future Supply of Medical Radioisotopes for the UK Report 2014

    CERN Document Server

    Neilly, Brian; Ballinger, Jim; Buscombe, John; Clarke, Rob; Ellis, Beverley; Flux, Glenn; Fraser, Louise; Hall, Adrian; Owen, Hywel; Paterson, Audrey; Perkins, Alan; Scarsbrook, Andrew

    2015-01-01

    The UK has no research nuclear reactors and relies on the importation of 99Mo and other medical radioisotopes (e.g. Iodine-131) from overseas (excluding PET radioisotopes). The UK is therefore vulnerable not only to global shortages, but to problems with shipping and importation of the products. In this context Professor Erika Denton UK national Clinical Director for Diagnostics requested that the British Nuclear Medicine Society lead a working group with stakeholders including representatives from the Science & Technology Facilities Council (STFC) to prepare a report. The group had a first meeting on 10 April 2013 followed by a working group meeting with presentations on 9th September 2013 where the scope of the work required to produce a report was agreed. The objectives of the report are: to describe the status of the use of medical radioisotopes in the UK; to anticipate the potential impact of shortages for the UK; to assess potential alternative avenues of medical radioisotope production for the UK m...

  20. Radioisotope study of Eustachian tube. A preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    De Rossi, G.; Campioni, P.; Vaccaro, A.

    1988-08-01

    Radioisotope studies of Eustachian tube are suggested in the preoperative phase of tympanoplasty, in order to assess tubal drainage and secretion. The use of gamma camera fitted to a computer allowed the AA, to calculate some semi-quantitative parameters for an exact assessment of the radioactivity transit from the tympanic cass up to the pharyngeal cavity, throughout the Eustachian tube.

  1. Radioisotope Production Plan and Strategy of Kijang Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kye Hong; Lee, Jun Sig [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    This reactor will be located at Kijang, Busan, Korea and be dedicated to produce mainly medical radioisotopes. Tc-99m is very important isotope for diagnosis and more than 80% of radiation diagnostic procedures in nuclear medicine depend on this isotope. There were, however, several times of insecure production of Mo-99 due to the shutdown of major production reactors worldwide. OECD/NEA is leading member countries to resolve the shortage of this isotope and trying to secure the international market of Mo-99. The radioisotope plan and strategy of Kijang Research Reactor (KJRR) should be carefully established to fit not only the domestic but also international demand on Mo-99. The implementation strategy of 6 principles of HLG-MR should be established that is appropriate to national environments. Ministry of Science, ICT and Future Planning and Ministry of Health and welfare should cooperate well to organize the national radioisotope supply structure, to set up the reasonable and competitive pricing of radioisotopes, and to cope with the international supply strategy.

  2. [Carbon isotope (13C/12C) effect of photorespiration in photosynthetic organisms. Evidence for existence, probable mechanism].

    Science.gov (United States)

    Ivlev, A A

    2002-01-01

    Experimental evidence in favor of the new phenomenon predicted for photosynthesizing organisms, the fractionation of carbon isotopes in photorespiration is presented. A possible mechanism of this process is discussed. The fractionation of carbon in isotopes photorespiration occurs in the oxygenase phase of the functioning of ribulosebisphosphate carboxylase/oxygenase (rubisco), the key enzyme of photosynthesis, which is capable to act as carboxylase and oxygenase. Which function of the enzyme is active depends on CO2/O2 concentration ratio, which periodically changes in a cell. The key reaction in the mechanism of carbon isotope fractionation in photorespiration is glycine decarboxylation, which results in the splitting and removal from the cell of CO2 enriched with 12C and the accumulation of 13C photorespiratory carbon flow. The coupling of photorespiration and CO2 photoassimilation gives rise to two isotopically different carbon flows, which fill up separate carbohydrate pools, which are the sources of carbon in the following syntheses in the dark phase of photosynthesis. This enables one to identify, from the carbon isotope ratio of metabolites, their involvement in the photorespiratory and assimilatory carbon flows, to investigate the pathways of carbon metabolism, and to estimate more thoroughly the biosynthetic role of photorespiration.

  3. Analysis of metal radioisotope impurities generated in [{sup 18}O]H{sub 2}O during the cyclotron production of fluorine-18

    Energy Technology Data Exchange (ETDEWEB)

    Gillies, J.M. [Cancer Research-UK/UMIST Radiochemical Targeting and Imaging Group, Christie Hospital NHS Trust, Paterson Institute for Cancer Research, Wilmslow Road, Manchester, M20 4BX (United Kingdom)]. E-mail: jgillies@picr.man.ac.uk; Najim, N. [Cancer Research-UK/UMIST Radiochemical Targeting and Imaging Group, Christie Hospital NHS Trust, Paterson Institute for Cancer Research, Wilmslow Road, Manchester, M20 4BX (United Kingdom); School of Chemical Engineering and Analytical Sciences, University of Manchester, P.O. Box 88, Manchester, M60 1QD (United Kingdom); Zweit, J. [Cancer Research-UK/UMIST Radiochemical Targeting and Imaging Group, Christie Hospital NHS Trust, Paterson Institute for Cancer Research, Wilmslow Road, Manchester, M20 4BX (United Kingdom); School of Chemical Engineering and Analytical Sciences, University of Manchester, P.O. Box 88, Manchester, M60 1QD (United Kingdom)

    2006-04-15

    We show the separation of metal radioistope impurities using capillary electrophoresis (CE). The methodology used is an improvement of existent protocols for separation of stable metal ions. Production of fluorine-18 using [{sup 18}O]H{sub 2}O-enriched water encased in a titanium target body results in the production of several metal radioisotope impurities. Optimisation of the conditions for CE separation of the metal radioisotope impurities incorporated the use of 6 mM 18-Crown-6 in combination with 12 mM glycolic acid as complexing agents within the running buffer (10 mM pyridine, pH 4.0). Using this optimised procedure, we were able to separate and detect a number of metal radioisotopes, including chromium, cobalt, manganese, vanadium and berillium, within the fM concentration range.

  4. Synthesis and properties of novel aliphatic polycarbonate from carbon dioxide with 1,2-butylene oxide and ε-caprolactone

    Institute of Scientific and Technical Information of China (English)

    Yan Fei Liu; Ke Long Huang; Dong Ming Peng; Su Qin Liu; Hong Wu

    2007-01-01

    A new degradable aliphatic poly(butylene-co-ε-caprolactone carbonate) (PBCL) was synthesized through the terpolymerization of carbon dioxide, 1,2-butylene oxide (BO) and ε-caprolactone (CL), a polymer supported bimetallic complex (PBM) was used as a catalyst. The terpolymers prepared were characterized by FT-IR, 1H NMR, 13C NMR, WXRD and DSC. The hydrolysis tests were carried out to appraise the degradability of the copolymers.

  5. Applications of radioisotopes in industry and healthcare in Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Dien, N.N.; Quang, N.H. [Nucealr Research Institute, Dalat, (Viet Nam)

    1997-10-01

    Nowadays, in Vietnam radioisotopes have been used very widely in various socio-economic branches, especially in industry and healthcare. Applications of radioisotopes have significant meaning in economic development, people health protection, as well as in scientific research. In this paper, the present status and main applications of radiation and radioactive isotopes in industry and healthcare in Vietnam are reported. In order to control and monitor industrial processes, nucleonic control systems and radioactive tracer techniques have been utilized. Actually, sealed source applications are popular in Vietnam industry. A number of nuclear control devices and gauges have been used in the various industrial factories, such as liquid level gauges in steel industry, cement and beverage factories; density and moisture gauges in paper industry, etc. Tracer technique and sealed source applications have also been utilized in industrial production plants and in trouble-shooting in the petroleum industry. For medicine purposes, two departments of nuclear medicine were primarily established at the beginning of the 1970s. At the present time, a number of nuclear medicine departments have been set up and they have been equipped with advanced equipment. Main activities are focused on thyroid function studies, nuclear cardiology, brain scans, gastrointestinal studies, bone scans, etc. Since march 1984 Dalat nuclear research reactor of nominal power of 500 kW has been reconstructed and put into operation. This reactor is unique in Vietnam and has become an important scientific tool for development of nuclear techniques and radioisotope applications for socio-economic progress. Thanks to this important scientific tool, a variety of radioisotopes for medicine and industry applications as well as for scientific research has been produced. Utilization of the Dalat research reactor for radioisotope production is also summarized in this paper

  6. Production capabilities in US nuclear reactors for medical radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Mirzadeh, S.; Callahan, A.P.; Knapp, F.F. Jr. [Oak Ridge National Lab., TN (United States); Schenter, R.E. [Westinghouse Hanford Co., Richland, WA (United States)

    1992-11-01

    The availability of reactor-produced radioisotopes in the United States for use in medical research and nuclear medicine has traditionally depended on facilities which are an integral part of the US national laboratories and a few reactors at universities. One exception is the reactor in Sterling Forest, New York, originally operated as part of the Cintichem (Union Carbide) system, which is currently in the process of permanent shutdown. Since there are no industry-run reactors in the US, the national laboratories and universities thus play a critical role in providing reactor-produced radioisotopes for medical research and clinical use. The goal of this survey is to provide a comprehensive summary of these production capabilities. With the temporary shutdown of the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) in November 1986, the radioisotopes required for DOE-supported radionuclide generators were made available at the Brookhaven National Laboratory (BNL) High Flux Beam Reactor (HFBR). In March 1988, however, the HFBR was temporarily shut down which forced investigators to look at other reactors for production of the radioisotopes. During this period the Missouri University Research Reactor (MURR) played an important role in providing these services. The HFIR resumed routine operation in July 1990 at 85 MW power, and the HFBR resumed operation in June 1991, at 30 MW power. At the time of the HFBR shutdown, there was no available comprehensive overview which could provide information on status of the reactors operating in the US and their capabilities for radioisotope production. The obvious need for a useful overview was thus the impetus for preparing this survey, which would provide an up-to-date summary of those reactors available in the US at both the DOE-funded national laboratories and at US universities where service irradiations are currently or expected to be conducted.

  7. A PHOTOCHEMICAL MODEL FOR THE CARBON-RICH PLANET WASP-12b

    Energy Technology Data Exchange (ETDEWEB)

    Kopparapu, Ravi kumar; Kasting, James F. [Department of Geosciences, Penn State University, 443 Deike Building, University Park, PA 16802 (United States); Zahnle, Kevin J. [NASA Ames Research Center, MS 245-3, Moffett Field, CA 94035 (United States)

    2012-01-20

    The hot-Jupiter WASP-12b is a heavily irradiated exoplanet in a short-period orbit around a G0-star with twice the metallicity of the Sun. A recent thermochemical equilibrium analysis based on Spitzer and ground-based infrared observations suggests that the presence of CH{sub 4} in its atmosphere and the lack of H{sub 2}O features can only be explained if the carbon-to-oxygen ratio in the planet's atmosphere is much greater than the solar ratio ([C]/[O] = 0.54). Here, we use a one-dimensional photochemical model to study the effect of disequilibrium chemistry on the observed abundances of H{sub 2}O, CO, CO{sub 2}, and CH{sub 4} in the WASP-12b atmosphere. We consider two cases: one with solar [C]/[O] and another with [C]/[O] = 1.08. The solar case predicts that H{sub 2}O and CO are more abundant than CO{sub 2} and CH{sub 4}, as expected, whereas the high [C]/[O] model shows that CO, C{sub 2}H{sub 2}, and HCN are more abundant. This indicates that the extra carbon from the high [C]/[O] model is in hydrocarbon species. H{sub 2}O photolysis is the dominant disequilibrium mechanism that alters the chemistry at higher altitudes in the solar [C]/[O] case, whereas photodissociation of C{sub 2}H{sub 2} and HCN is significant in the super-solar case. Furthermore, our analysis indicates that C{sub 2}H{sub 2} is the major absorber in the atmosphere of WASP-12b and the absorption features detected near 1.6 and 8 {mu}m may be arising from C{sub 2}H{sub 2} rather than CH{sub 4}. The Hubble Space Telescope's WFC3 can resolve this discrepancy, as C{sub 2}H{sub 2} has absorption between 1.51 and 1.54 {mu}m, while CH{sub 4} does not.

  8. Is Radioactive Decay Really Exponential?

    CERN Document Server

    Aston, Philip J

    2012-01-01

    Radioactive decay of an unstable isotope is widely believed to be exponential. This view is supported by experiments on rapidly decaying isotopes but is more difficult to verify for slowly decaying isotopes. The decay of 14C can be calibrated over a period of 12,550 years by comparing radiocarbon dates with dates obtained from dendrochronology. It is well known that this approach shows that radiocarbon dates of over 3,000 years are in error, which is generally attributed to past variation in atmospheric levels of 14C. We note that predicted atmospheric variation (assuming exponential decay) does not agree with results from modelling, and that theoretical quantum mechanics does not predict exact exponential decay. We give mathematical arguments that non-exponential decay should be expected for slowly decaying isotopes and explore the consequences of non-exponential decay. We propose an experimental test of this prediction of non-exponential decay for 14C. If confirmed, a foundation stone of current dating meth...

  9. Electrophysiological Monitoring in Patients With Tumors of the Skull Base Treated by Carbon-12 Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Carozzo, Simone [Department of Neuroscience, Ophthalmology, and Genetics, University of Genova, Genova (Italy); Schardt, Dieter [Department of Biophysics, GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Narici, Livio [Department of Physics, University of Rome Tor Vergata, Rome (Italy); Combs, Stephanie E.; Debus, Jürgen [Department of Radiation Oncology, University of Heidelberg, Heidelberg (Germany); Sannita, Walter G., E-mail: wgs@dism.unige.it [Department of Neuroscience, Ophthalmology, and Genetics, University of Genova, Genova (Italy); Department of Psychiatry, State University of New York, Stony Brook, New York (United States)

    2013-03-15

    Purpose: To report the results of short-term electrophysiologic monitoring of patients undergoing {sup 12}C therapy for the treatment of skull chordomas and chondrosarcomas unsuitable for radical surgery. Methods and Materials: Conventional electroencephalogram (EEG) and retinal and cortical electrophysiologic responses to contrast stimuli were recorded from 30 patients undergoing carbon ion radiation therapy, within a few hours before the first treatment and after completion of therapy. Methodologies and procedures were compliant with the guidelines of the International Federation for Clinical Neurophysiology and International Society for Clinical Electrophysiology of Vision. Results: At baseline, clinical signs were reported in 56.6% of subjects. Electrophysiologic test results were abnormal in 76.7% (EEG), 78.6% (cortical evoked potentials), and 92.8% (electroretinogram) of cases, without correlation with neurologic signs, tumor location, or therapy plan. Results on EEG, but not electroretinograms and cortical responses, were more often abnormal in patients with reported clinical signs. Abnormal EEG results and retinal/cortical responses improved after therapy in 40% (EEG), 62.5% (cortical potentials), and 70% (electroretinogram) of cases. Results on EEG worsened after therapy in one-third of patients whose recordings were normal at baseline. Conclusions: The percentages of subjects whose EEG results improved or worsened after therapy and the improvement of retinal/cortical responses in the majority of patients are indicative of a limited or negligible (and possibly transient) acute central nervous system toxicity of carbon ion therapy, with a significant beneficial effect on the visual pathways. Research on large samples would validate electrophysiologic procedures as a possible independent test for central nervous system toxicity and allow investigation of the correlation with clinical signs; repeated testing over time after therapy would demonstrate, and may

  10. B decays

    CERN Document Server

    Stone, Sheldon

    1994-01-01

    This book reviews the study of b quarks and also looks at the implications of future studies. The most important observations thus far - including measurement of the ""B"" lifetime and observations of b -> u transitions - as well as the more mundane results of hadronic and semileptonic transitions are described in detail by experimentalists who have been closely involved with the measurements. Theoretical progress in understanding b quark decays, including the mechanisms of hadronic and semileptonic decays, are described. Synthesizing the experimental and theoretical information, the authors d

  11. B decays

    CERN Document Server

    Stone, Sheldon

    1992-01-01

    The study of b quarks has now reached a stage where it is useful to review what has been learned so far and also to look at the implications of future studies. The most important observations thus far - measurement of the "B" lifetime, B 0 - B 0 mixing, and the observation of b? u transitions, as well as more mundane results on hadronic and semileptonic transitions - are described in detail by experimentalists who have been closely involved with the measurements. Theoretical progress in understanding b quark decays, including the mechanisms of hadronic and semileptonic decays, are described. S

  12. Cyclotron-produced radioisotopes and their clinical use at the Austin PET Centre

    Energy Technology Data Exchange (ETDEWEB)

    Tochon-Danguy, H.J. [Centre for PET, Melbourne, VIC (Australia). Austin and Repatriation Medical Centre

    1997-12-31

    A Centre for Positron Emission Tomography (PET) has been established within the Department of Nuclear Medicine at the Austin and Repatriation Medical Centre in Melbourne. PET is a non-invasive technique based on the use of biologically relevant compounds labelled with short-lived positron-emitting radionuclides such as carbon-11, nitrogen-13, oxygen-15 and fluorine-18. The basic equipment consists of a medical cyclotron (10 MeV proton and 5 MeV deuteron), six lead-shielded hot cells with associated radiochemistry facilities and a whole body PET scanner. During its first five years of operation, the Melbourne PET Centre, has pursued a strong radiolabelling development program, leading to an ambitious clinical program in neurology, oncology and cardiology. This presentation will describe the basic principles of the PET technique and review the cyclotron-produced radioisotopes and radiopharmaceuticals. Radiolabelling development programs and clinical applications are also addressed. 30 refs., 1 tab., 1 fig.

  13. InfuShield: a shielded enclosure for administering therapeutic radioisotope treatments using standard syringe pumps.

    Science.gov (United States)

    Rushforth, Dominic P; Pratt, Brenda E; Chittenden, Sarah J; Murray, Iain S; Causer, Louise; Grey, Matthew J; Gear, Jonathan I; Du, Yong; Flux, Glenn D

    2017-03-01

    The administration of radionuclide therapies presents significant radiation protection challenges. The aim of this work was to develop a delivery system for intravenous radioisotope therapies to substantially moderate radiation exposures to staff and operators. A novel device (InfuShield) was designed and tested before being used clinically. The device consists of a shielded enclosure which contains the therapeutic activity and, through the hydraulic action of back-to-back syringes, allows the activity to be administered using a syringe pump external to the enclosure. This enables full access to the pump controls while simultaneously reducing dose to the operator. The system is suitable for use with all commercially available syringe pumps and does not require specific consumables, maximising both the flexibility and economy of the system. Dose rate measurements showed that at key stages in an I mIBG treatment procedure, InfuShield can reduce dose to operators by several orders of magnitude. Tests using typical syringes and infusion speeds show no significant alteration in administered flow rates (maximum of 1.2%). The InfuShield system provides a simple, safe and low cost method of radioisotope administration.

  14. Search for charged Higgs bosons in decays of top quarks in p anti-p collisions at s**(1/2) = 1.96 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Aaltonen, T.; /Helsinki U. /Helsinki Inst. of Phys.; Adelman, J.; /Chicago U., EFI; Akimoto, T.; /Tsukuba U.; Alvarez Gonzalez, B.; /Cantabria Inst. of Phys.; Amerio, S.; /Padua U. /INFN, Padua; Amidei, D.; /Michigan U.; Anastassov, A.; /Northwestern U.; Annovi, A.; /Frascati; Antos, J.; /Comenius U.; Apollinari, G.; /Fermilab; Apresyan, A.; /Purdue U. /Waseda U.

    2009-07-01

    We report on the first direct search for charged Higgs bosons in decays of top quarks in p{bar p} collisions at {radical}s = 1.96 TeV. The search uses a data sample corresponding to an integrated luminosity of 2.2 fb{sup -1} collected by the CDF II detector at Fermilab, and looks for a resonance in the invariant mass distribution of two jets in the lepton+jets sample of t{bar t} candidates. We observe no evidence of charged Higgs bosons in top quark decays. Hence, 95% upper limits on the top quark decay branching ratio are placed at {Beta}(t {yields} H{sup +}b) < 0.1 to 0.3 for charged Higgs boson masses of 60 to 150 GeV/c{sup 2}, assuming {Beta}(H{sup +} {yields} c{bar s}) = 1.0. The upper limits on {Beta}(t {yields} H{sup +}b) can also be used as model-independent limits on the decay branching ratio of top quarks to generic scalar charged bosons beyond the standard model.

  15. Quantification of the decay and re-induction of heat acclimation in dry-heat following 12 and 26 days without exposure to heat stress

    NARCIS (Netherlands)

    Weller, A.S.; Linnane, D.M.; Jonkman, A.G.; Daanen, H.A.M.

    2007-01-01

    Compared with the induction of heat acclimation (HA), studies investigating the decay and re-induction of HA (RA) are relatively sparse and have yielded conflicting results. Therefore, 16 semi-nude men were acclimated to dry-heat by undertaking an exercise protocol in a hot chamber (dry-bulb tempera

  16. Process for radioisotope recovery and system for implementing same

    Science.gov (United States)

    Meikrantz, David H.; Todd, Terry A.; Tranter, Troy J.; Horwitz, E. Philip

    2007-01-02

    A method of recovering daughter isotopes from a radioisotope mixture. The method comprises providing a radioisotope mixture solution comprising at least one parent isotope. The at least one parent isotope is extracted into an organic phase, which comprises an extractant and a solvent. The organic phase is substantially continuously contacted with an aqueous phase to extract at least one daughter isotope into the aqueous phase. The aqueous phase is separated from the organic phase, such as by using an annular centrifugal contactor. The at least one daughter isotope is purified from the aqueous phase, such as by ion exchange chromatography or extraction chromatography. The at least one daughter isotope may include actinium-225, radium-225, bismuth-213, or mixtures thereof. A liquid-liquid extraction system for recovering at least one daughter isotope from a source material is also disclosed.

  17. Investigation of Insulation Materials for Future Radioisotope Power Systems

    Science.gov (United States)

    Cornell, Peggy A.; Hurwitz, Frances I.; Ellis, David L.; Schmitz, Paul C.

    2013-01-01

    NASA's Radioisotope Power Systems (RPS) Technology Advancement Project is developing next generation high-temperature insulation materials that directly benefit thermal management and improve performance of RPS for future science missions. Preliminary studies on the use of multilayer insulation (MLI) for Stirling convertors used on the Advanced Stirling Radioisotope Generator (ASRG) have shown the potential benefits of MLI for space vacuum applications in reducing generator size and increasing specific power (W/kg) as compared to the baseline Microtherm HT (Microtherm, Inc.) insulation. Further studies are currently being conducted at NASA Glenn Research Center on candidate MLI foils and aerogel composite spacers. This paper presents the method of testing of foils and spacers and experimental results to date.

  18. Investigation of Insulation Materials for Future Radioisotope Power Systems (RPS)

    Science.gov (United States)

    Cornell, Peggy A.; Hurwitz, Frances I.; Ellis, David L.; Schmitz, Paul C.

    2013-01-01

    NASA's Radioisotope Power System (RPS) Technology Advancement Project is developing next generation high temperature insulation materials that directly benefit thermal management and improve performance of RPS for future science missions. Preliminary studies on the use of multilayer insulation (MLI) for Stirling convertors used on the Advanced Stirling Radioisotope Generator (ASRG) have shown the potential benefits of MLI for space vacuum applications in reducing generator size and increasing specific power (W/kg) as compared to the baseline Microtherm HT (Microtherm, Inc.) insulation. Further studies are currently being conducted at NASA Glenn Research Center (GRC) on candidate MLI foils and aerogel composite spacers. This paper presents the method of testing of foils and spacers and experimental results to date.

  19. Solid state radioisotopic energy converter for space nuclear power

    Energy Technology Data Exchange (ETDEWEB)

    Brown, P.M. (IsoGen Radioisotopic Research Laboratory, 315 S. McLoughlin Blvd., Oregon City, Oregon 97045 (United States))

    1993-01-10

    Recent developments in materials technology now make it possible to fabricate nonthermal thin-film radioisotopic energy converters (REC) with a specific power of 24 W/kg and a 10 year working life at 5 to 10 watts. This creates applications never before possible, such as placing the power supply directly on integrated circuit chips. The efficiency of the REC is about 25% which is two to three times greater than the 6 to 8% capabilities of current thermoelectric systems. Radioisotopic energy converters have the potential to meet many future space power requirements for a wide variety of applications with less mass, better efficiency, and less total area than other power conversion options. These benefits result in significant dollar savings over the projected mission lifetime.

  20. Opportunities for Decay Counting of Environmental Radioisotopes Using Ultra-low-background Detection Systems

    Energy Technology Data Exchange (ETDEWEB)

    Runkle, Robert C.; Aalseth, Craig E.; Bailey, Vanessa L.; Bonicalzi, Ricco; Moran, James J.; Seifert, Allen; Warren, Glen A.

    2012-08-01

    Executive Summary We present results from a scoping study whose intent was to define challenge measurements to be pursued on the Ultra-Sensitive Nuclear Measurements Initiative. Potential challenge measurements using new radiation detection technology in the shallow underground laboratory that would have substantial impact in environmental science were the focus of this study.

  1. Carbon-rich presolar grains from massive stars. Subsolar 12C/13C and 14N/15N ratios and the mystery of 15N

    CERN Document Server

    Pignatari, M; Hoppe, P; Jordan, C J; Gibson, B K; Trappitsch, R; Herwig, F; Fryer, C; Hirschi, R; Timmes, F X

    2015-01-01

    Carbon-rich grains with isotopic anomalies compared to the Sun are found in primitive meteorites. They were made by stars, and carry the original stellar nucleosynthesis signature. Silicon carbide grains of Type X and C, and low-density graphites condensed in the ejecta of core-collapse supernovae. We present a new set of models for the explosive He shell and compare them with the grains showing 12C/13C and 14N/15N ratios lower than solar. In the stellar progenitor H was ingested into the He shell and not fully destroyed before the explosion. Different explosion energies and H concentrations are considered. If the SN shock hits the He-shell region with some H still present, the models can reproduce the C and N isotopic signatures in C-rich grains. Hot-CNO cycle isotopic signatures are obtained, including a large production of 13C and 15N. The short-lived radionuclides 22Na and 26Al are increased by orders of magnitude. The production of radiogenic 22Ne from the decay of 22Na in the He shell might solve the pu...

  2. Plastic Gamma Sensors: An Application in Detection of Radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    S. Mukhopadhyay

    2003-06-01

    A brief survey of plastic scintillators for various radiation measurement applications is presented here. The utility of plastic scintillators for practical applications such as gamma radiation monitoring, real-time radioisotope detection and screening is evaluated in laboratory and field measurements. This study also reports results of Monte Carlo-type predictive responses of common plastic scintillators in gamma and neutron radiation fields. Small-size plastic detectors are evaluated for static and dynamic gamma-ray detection sensitivity of selected radiation sources.

  3. NASA's Radioisotope Power Systems Planning and Potential Future Systems Overview

    Science.gov (United States)

    Zakrajsek, June F.; Woerner, Dave F.; Cairns-Gallimore, Dirk; Johnson, Stephen G.; Qualls, Louis

    2016-01-01

    The goal of NASA's Radioisotope Power Systems (RPS) Program is to make RPS ready and available to support the exploration of the solar system in environments where the use of conventional solar or chemical power generation is impractical or impossible to meet the needs of the missions. To meet this goal, the RPS Program, working closely with the Department of Energy, performs mission and system studies (such as the recently released Nuclear Power Assessment Study), assesses the readiness of promising technologies to infuse in future generators, assesses the sustainment of key RPS capabilities and knowledge, forecasts and tracks the Program's budgetary needs, and disseminates current information about RPS to the community of potential users. This process has been refined and used to determine the current content of the RPS Program's portfolio. This portfolio currently includes an effort to mature advanced thermoelectric technology for possible integration into an enhanced Multi-Mission Radioisotope Generator (eMMRTG), sustainment and production of the currently deployed MMRTG, and technology investments that could lead to a future Stirling Radioisotope Generator (SRG). This paper describes the program planning processes that have been used, the currently available MMRTG, and one of the potential future systems, the eMMRTG.

  4. NASA's Radioisotope Power Systems Planning and Potential Future Systems Overview

    Science.gov (United States)

    Zakrajsek, June F.; Woerner, Dave F.; Cairns-Gallimore, Dirk; Johnson, Stephen G.; Qualis, Louis

    2016-01-01

    The goal of NASA's Radioisotope Power Systems (RPS) Program is to make RPS ready and available to support the exploration of the solar system in environments where the use of conventional solar or chemical power generation is impractical or impossible to meet the needs of the missions. To meet this goal, the RPS Program, working closely with the Department of Energy, performs mission and system studies (such as the recently released Nuclear Power Assessment Study), assesses the readiness of promising technologies to infuse in future generators, assesses the sustainment of key RPS capabilities and knowledge, forecasts and tracks the Programs budgetary needs, and disseminates current information about RPS to the community of potential users. This process has been refined and used to determine the current content of the RPS Programs portfolio. This portfolio currently includes an effort to mature advanced thermoelectric technology for possible integration into an enhanced Multi-Mission Radioisotope Generator (eMMRTG), sustainment and production of the currently deployed MMRTG, and technology investments that could lead to a future Stirling Radioisotope Generator (SRG). This paper describes the program planning processes that have been used, the currently available MMRTG, and one of the potential future systems, the eMMRTG.

  5. Advanced Thermoelectric Materials for Radioisotope Thermoelectric Generators

    Science.gov (United States)

    Caillat, Thierry; Hunag, C.-K.; Cheng, S.; Chi, S. C.; Gogna, P.; Paik, J.; Ravi, V.; Firdosy, S.; Ewell, R.

    2008-01-01

    This slide presentation reviews the progress and processes involved in creating new and advanced thermoelectric materials to be used in the design of new radioiootope thermoelectric generators (RTGs). In a program with Department of Energy, NASA is working to develop the next generation of RTGs, that will provide significant benefits for deep space missions that NASA will perform. These RTG's are planned to be capable of delivering up to 17% system efficiency and over 12 W/kg specific power. The thermoelectric materials being developed are an important step in this process.

  6. World Carbon Black Output to Reach 12.7 Million Tons in 2015

    Institute of Scientific and Technical Information of China (English)

    Zhu Yongkang

    2012-01-01

    From April 13 to April 17, "Carbon Black China of 2012" (CBC2012) was held in Hangzhou, China. Mr. Paul Ita, the president of US marketing research institution Notch Consulting Group, announced that the prospect of carbon black industry was closely linked with the development of auto industry and tire industry. The demand for carbon black of 2010 increased by 15% compared with that of 2009; the growth rate of demand for carbon black was 5.8% in 2011 and the total output was 10.7 million tons, which increased by about 5.5% compared with that of 2010.

  7. 40 CFR 600.113-12 - Fuel economy and carbon-related exhaust emission calculations for FTP, HFET, US06, SC03 and cold...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Fuel economy and carbon-related... ECONOMY AND CARBON-RELATED EXHAUST EMISSIONS OF MOTOR VEHICLES Fuel Economy Regulations for 1978 and Later Model Year Automobiles-Test Procedures § 600.113-12 Fuel economy and carbon-related exhaust...

  8. G64-12 and G64-37 are Carbon-Enhanced Metal-Poor Stars

    CERN Document Server

    Placco, Vinicius M; Reggiani, Henrique; Melendez, Jorge

    2016-01-01

    We present new high-resolution chemical-abundance analyses for the well-known high proper-motion subdwarfs G64-12 and G64-37, based on very high signal-to-noise spectra (S/N ~ 700/1) with resolving power R ~ 95,000. These high-quality data enable the first reliable determination of the carbon abundances for these two stars; we classify them as carbon-enhanced metal-poor (CEMP) stars based on their carbonicities, which both exceed [C/Fe] = +1.0. They are sub-classified as CEMP- no Group-II stars, based on their location in the Yoon-Beers diagram of absolute carbon abundance, A(C) vs. [Fe/H], as well as on the conventional diagnostic [Ba/Fe]. The relatively low absolute carbon abundances of CEMP-no stars, in combination with the high effective temperatures of these two stars (Teff ~ 6500 K) weakens their CH molecular features to the point that accurate carbon abundances can only be estimated from spectra with very high S/N. A comparison of the observed abundance patterns with the predicted yields from massive, ...

  9. Search for particles decaying into a Z boson and a photon in p anti-p collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; /Buenos Aires U. /Rio de

    2006-05-01

    The authors present the results of the first search for a new particle X produced in p{bar p} collisions at {radical}s = 1.96 TeV and subsequently decaying to Z{gamma}. The search uses 0.3 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron Collider. They set limits on the production cross section times the branching fraction {sigma}(p{bar p} {yields} X) x B(X {yields} Z{gamma}) that range from 0.4-3.5 pb at the 95% C.L. for X with invariant masses between 100 and 1000 GeV/c{sup 2} over a wide range of X decay widths.

  10. Top pair production cross section at s**(1/2) = 1.96 TeV and a search for v + a current in top quark decay

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera, S.; /Valencia U., IFIC

    2006-09-01

    Possible effects from physics beyond the Standard Model have been investigated in top quark decays from a data sample enriched in t{bar t} events produced in p{bar p} collisions at {radical}s = 1.96 TeV with an integrated luminosity of approximately 700 pb{sup -1} and collected with the CDF II detector. The combined t{bar t} production cross section measurement 7.3 {+-} 0.9 pb agrees with the QCD NLO predictions: 6.7 {+-} 0.8 pb assuming m{sub top} = 175 GeV/c{sup 2}. The fraction of the V + A current in top quark decay, f{sub V+A}, is determined using the invariant mass of the charged lepton and the bottom quark jet in the decay chain t {yields} Wb {yields} {ell}{nu}b (where {ell} = e or {mu}). The measured value f{sub V+A} = - 0.06 {+-} 0.25 under the assumption m{sub top} = 175 GeV/c{sup 2} is in agreement with the Standard Model. They set an upper limit on f{sub V+A} of 0.29 at the 95% confidence level.

  11. Application of hybrid supercapacitor using granule Li4Ti5O12/activated carbon with variation of current density

    Science.gov (United States)

    Lee, Byung-Gwan; Lee, Seung-Hwan

    2017-03-01

    We report the electrochemical performance of asymmetric hybrid supercapacitors composed of granule Li4Ti5O12 as an anode and activated carbon as a cathode with different current densities. It is demonstrated that the hybrid supercapacitors show good initial discharge capacities were ranged from 39.8 to 46.4 F g-1 in the current densities range of 0.3-1 A g-1. The performance degradation is proportional to the current density due to quick gassing, resulting from H2O and HF formation. In particular, the hybrid supercapacitors show the pretty good cycling stability of 97.4%, even at the high current density of 0.8 A g-1, which are among most important performance in the real application for energy storage devices. Therefore, we believe that hybrid supercapacitors using granule Li4Ti5O12/activated carbon are eligible for the promising next generation energy devices.

  12. Degradation mechanism of Direct Pink 12B treated by iron-carbon micro-electrolysis and Fenton reaction.

    Science.gov (United States)

    Wang, Xiquan; Gong, Xiaokang; Zhang, Qiuxia; Du, Haijuan

    2013-12-01

    The Direct Pink 12B dye was treated by iron-carbon micro-electrolysis (ICME) and Fenton oxidation. The degradation pathway of Direct Pink 12B dye was inferred by ultraviolet visible (UV-Vis), infrared absorption spectrum (IR) and high performance liquid chromatography-mass spectrometry (HPLC-MS). The major reason of decolorization was that the conjugate structure was disrupted in the iron-carbon micro-electrolysis (ICME) process. However, the dye was not degraded completely because benzene rings and naphthalene rings were not broken. In the Fenton oxidation process, the azo bond groups surrounded by higher electron cloud density were first attacked by hydroxyl radicals to decolorize the dye molecule. Finally benzene rings and naphthalene rings were mineralized to H2O and CO2 under the oxidation of hydroxyl radicals.

  13. Vision changes after spaceflight are related to alterations in folate- and vitamin B-12-dependent one-carbon metabolism.

    Science.gov (United States)

    Zwart, Sara R; Gibson, C Robert; Mader, Thomas H; Ericson, Karen; Ploutz-Snyder, Robert; Heer, Martina; Smith, Scott M

    2012-03-01

    Approximately 20% (7 of 38) of astronauts on International Space Station (ISS) missions have developed measurable ophthalmic changes after flight. This study was conducted to determine if the folate- and vitamin B-12-dependent 1-carbon metabolic pathway is altered in these individuals. Since 2006, we have conducted experiments on the ISS to evaluate nutritional status and related biochemical indices of astronauts before, during, and after flight. Data were modeled to evaluate differences between individuals with ophthalmic changes (n = 5) and those without them (n = 15), all of whom were on ISS missions of 48-215 d. We also determined whether mean preflight serum concentrations of the 1-carbon metabolites and changes in measured cycloplegic refraction after flight were associated. Serum homocysteine (Hcy), cystathionine, 2-methylcitric acid (2MCA), and methylmalonic acid concentrations were 25-45% higher (P refraction (P < 0.05), and preflight serum concentrations of 2MCA tended to be associated (P = 0.06) with ophthalmic changes. The biochemical differences observed in crewmembers with vision issues strongly suggest that their folate- and vitamin B-12-dependent 1-carbon transfer metabolism was affected before and during flight. The consistent differences in markers of 1-carbon metabolism between those who did and those who did not develop changes in vision suggest that polymorphisms in enzymes of this pathway may interact with microgravity to cause these pathophysiologic changes.

  14. Decay of the excited compound system {sup 48}Cr{sup *} formed through {sup 24}Mg + {sup 24}Mg, {sup 36}Ar + {sup 12}C and {sup 20}Ne + {sup 28}Si reactions

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh, K.P.; Subha, P.V.; Priyanka, B. [Kannur University, School of Pure and Applied Physics, Payyanur, Kerala (India)

    2016-05-15

    The total cross section, the intermediate mass fragment (IMF) production cross section, and the cross section for the formation of light particle (LP) for the decay of {sup 48}Cr{sup *} formed through the entrance channel {sup 24}Mg+{sup 24}Mg, have been evaluated using the barrier penetration model, taking the scattering potential as the sum of the Coulomb and nuclear proximity potential, for various E{sub CM} values. The computed results have been compared with the available experimental data of the total cross section corresponding to E{sub CM}=44.4 MeV for the entrance channel {sup 24}Mg+{sup 24}Mg, and were found to be in good agreement. The experimental values for the LP production cross section for the channel {sup 24}Mg+{sup 24}Mg were also seen to be agreeing with our calculations. Hence we have extended our studies and have thus computed the total cross section, IMF cross section and LP cross section for the decay of {sup 48}Cr{sup *} formed through the other two entrance channels {sup 36}Ar+{sup 12}C, and {sup 20}Ne+{sup 28}Si with different E{sub CM} values. It was found that the computed total cross sections for the entrance channel {sup 36}Ar+{sup 12}C with E{sub CM}=47 MeV agree well with the corresponding experimental values. Hence, we hope that our predictions on the evaluations of the IMF cross sections and the light charged particle cross sections for the decay of {sup 48}Cr{sup *}, formed through the two entrance channels {sup 36}Ar+{sup 12}C, and {sup 20}Ne+{sup 28}Si, can be used for further experimental studies. (orig.)

  15. Feasibility of Thulium-170, Produced on Site, for Radioisotope Power Generation

    Science.gov (United States)

    Brennan, Charles; Mathews, Kirk

    1994-07-01

    Thulium-170 has been suggested as a replacement for 238Pu jn some radioisotope power generation applications. The proposed approach is to activate 169Tm within the core or reflector of a stationary site power nuclear reactor at a Lunar or Mars outpost. The 170Tm so produced offers high theoretical power densities without the toxicity, availability, and nuclear launch problems of plutonium (only stable 169Tm would be launched). We examined issues raised by previous studies. It would be desirable to activate the thulia repeatedly. The ORIGEN2 code was used to model repeated irradiation/decay of thulium sesquioxide. We found no substantial buildup of neutron absorbing activation products that would prohibit repeated irradiation of the sample. Throughout the life of the sample, the dominant activity was the 170Tm. There was no buildup of toxic substances. At end of life, the sample would be Class B waste. Another advantage of recycling is that, for the first several recyclings, recycled targets achieve the same power level as fresh ones, but with shorter activation periods (or higher power levels with the same activation periods). However, sufficient 170Tm could not be produced. Using neutron conservation arguments, we developed an absolute upper bound on l70Tm power production of 1/3 watt thermal per kilowatt thermal of reactor power. Realistic values are much lower. Thus, the envisioned application appears impractical, although limited uses for 170Tm power might be found.

  16. Direct measurement of the W boson decay width in proton-antiproton collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jun-jie

    2004-10-01

    This dissertation describes a direct measurement of the W boson total decay width, {Lambda}{sub W}, using the D0 detector at the Fermilab Tevatron Collider. The measurement uses an integrated luminosity of 177.3 pb{sup -1} data, collected during the 2002-2003 run. The width is determined from the shape of the transverse mass distribution, M{sub T}, by fitting the data in the tail region 100 < M{sub T} < 200 GeV. The result if {Lambda}{sub W} = 2.011 {+-} 0.093(stat) {+-} 0.107(syst) GeV.

  17. Inhibitory effects of multiwall carbon nanotubes with high iron impurity on viability and neuronal differentiation in cultured PC12 cells.

    Science.gov (United States)

    Meng, Li; Jiang, Aihua; Chen, Rui; Li, Chen-zhong; Wang, Liming; Qu, Ying; Wang, Peng; Zhao, Yuliang; Chen, Chunying

    2013-11-08

    The increasing use of carbon nanotubes (CNTs) in biomedical applications has garnered a great concern on their potential negative effects to human health. CNTs have been reported to potentially disrupt normal neuronal function and they were speculated to accumulate and cause brain damage, although a lot of distinct and exceptional properties and potential wide applications have been associated with this material in neurobiology. Fe impurities strapped inside the CNTs may be partially responsible for neurotoxicity generation. In the present study, we selected rat pheochromocytoma (PC12) cells to investigate and compare the effects of two kinds of multiwall carbon nanotubes (MWCNTs) with different concentrations of Fe impurities which usually come from the massive production of CNTs by chemical vapor deposition. Exposure to Fe-high MWCNTs can reduce cell viability and increase cytoskeletal disruption of undifferentiated PC12 cells, diminish the ability to form mature neurites, and then adversely influence the neuronal dopaminergic phenotype in NGF-treated PC-12 cells. The present results highlight the critical role of iron residue in the adverse response to MWCNTs exposure in neural cells. These findings provide useful information for understanding the toxicity and safe application of carbon nanotubes.

  18. Joint Radioisotope Electric Propulsion Studies - Neptune System Explorer

    Science.gov (United States)

    Khan, M. Omair; Amini, Rashied; Ervin, Joan; Lang, Jared; Landau, Damon; Oleson, Steven; Spilker, Thomas; Strange, Nathan

    2011-01-01

    The Neptune System Explorer (NSE) mission concept study assessed opportunities to conduct Cassini-like science at Neptune with a radioisotope electric propulsion (REP) based spacecraft. REP is based on powering an electric propulsion (EP) engine with a radioisotope power source (RPS). The NSE study was commissioned under the Joint Radioisotope Electric Propulsion Studies (JREPS) project, which sought to determine the technical feasibility of flagship class REP applications. Within JREPS, special emphasis was given toward identifying tall technology tent poles, as well as recommending any new RPS technology developments that would be required for complicated REP missions. Based on the goals of JREPS, multiple RPS (e.g. thermoelectric and Stirling based RPS) and EP (e.g. Hall and ion engines) technology combinations were traded during the NSE study to determine the most favorable REP design architecture. Among the findings from the study was the need for >400We RPS systems, which was driven by EP operating powers and the requirement for a long-lived mission in the deep solar system. Additionally multiple development and implementation risks were identified for the NSE concept, as well as REP missions in general. Among the strengths of the NSE mission would be the benefits associated with RPS and EP use, such as long-term power (approx. 2-3kW) at Neptune and flexible trajectory options for achieving orbit or tours of the Neptune system. Although there are still multiple issues to mitigate, the NSE concept demonstrated distinct advantages associated with using REP for deep space flagship-class missions.

  19. Radioisotope Stirling Generator Options for Pluto Fast Flyby Mission

    Energy Technology Data Exchange (ETDEWEB)

    Schock, Alfred

    2012-01-19

    The preceding paper described conceptual designs and analytical results for five Radioisotope Thermoelectric Generator (RTG) options for the Pluto Fast Flyby (PFF) mission, and the present paper describes three Radioisotope Stirling Generator (RSG) options for the same mission. The RSG options are based on essentially the same radioisotope heat source modules used in previously flown RTGs and on designs and analyses of a 75-watt free-piston Stirling engine produced by Mechanical Technology Incorporated (MTI) for NASA's Lewis Research Center. The integrated system design options presented were generated in a Fairchild Space study sponsored by the Department of Energy's Office of Special Applications, in support of ongoing PFF mission and spacecraft studies that the Jet Propulsion Laboratory (JPL) is conducting for the National Aeronautics and Space Administration (NASA). That study's NASA-directed goal is to reduce the spacecraft mass from its baseline value of 166 kg to ~110 kg, which implies a mass goal of less than 10 kg for a power source able to deliver 69 watts(e) at the end of the 9.2-year mission. In general, the Stirling options were found to be lighter than the thermoelectric options described in the preceding paper. But they are less mature, requiring more development, and entailing greater programmatic risk. The Stirling power system mass ranged from 7.3 kg (well below the 10-kg goal) for a non-redundant system to 11.3 kg for a redundant system able to maintain full power if one of its engines fails. In fact, the latter system could deliver as much as 115 watts(e) if desired by the mission planners. There are 2 copies in the file.

  20. Development of Next Generation Segmented Thermoelectric Radioisotope Power Systems

    Science.gov (United States)

    Fleurial, J.; Caillat, T.; Ewell, R. C.

    2005-12-01

    Radioisotope thermoelectric generators have been used for space-based applications since 1961 with a total of 22 space missions that have successfully used RTGs for electrical power production. The key advantages of radioisotope thermoelectric generators (RTGs) are their long life, robustness, compact size, and high reliability. Thermoelectric converters are easily scalable, and possess a linear current-voltage curve, making power generation easy to control via a shunt regulator and shunt radiator. They produce no noise, vibration or torque during operation. These properties have made RTGs ideally suitable for autonomous missions in the extreme environments of outer space and on planetary surfaces. More advanced radioisotope power systems (RPS) with higher specific power (W/kg) and/or power output are desirable for future NASA missions, including the Europa Geophysical Orbiter mission. For the past few years, the Jet Propulsion Laboratory (JPL) has been developing more efficient thermoelectric materials and has demonstrated significant increases in the conversion efficiency of high temperature thermocouples, up to 14% when operated across a 975K to 300K temperature differential. In collaboration with NASA Glenn Research Center, universities (USC and UNM), Ceramic and Metal Composites Corporation and industrial partners, JPL is now planning to lead the research and development of advanced thermoelectric technology for integration into the next generations of RPS. Preliminary studies indicate that this technology has the potential for improving the RPS specific power by more than 50% over the current state-of-the-art multi-mission RTG being built for the Mars Science Laboratory mission. A second generation advanced RPS is projected at more than doubling the specific power.

  1. A radioisotope powered cryobot for penetrating the Europan ice shell

    Science.gov (United States)

    Zimmerman, Wayne; Bryant, Scott; Zitzelberger, John; Nesmith, Bill

    2001-02-01

    The Cryobot team at JPL has been working on the design of a Cryo-Hydro Integrated Robotic Penetrator System (CHIRPS), which can be used to penetrate the Mars North Polar Cap or the thick sheet ice surrounding Jupiter's moon, Europa. The science for either one of these missions is compelling. For both Mars and Europa the major scientific interest is to reach regions where there is a reservoir of water that may yield signs of past or extant life. Additionally, a Mars polar cap penetration would help us understand both climatic and depositional histories for perhaps as far back as 20 million years. Similarly, penetration of the Europa ice sheet would allow scientists to unravel the mysteries surrounding the thick ice crust, its chemical composition, and subsurface ocean properties. Extreme mass and power constraints make deep drilling/coring impractical. The best way to explore either one of these environments is a cryobot mole penetrator vehicle, which carries a suite of instruments suitable for sampling and analyzing the ice or ocean environments. This paper concentrates on a Europa deep ice (i.e., kilometers thick) application of the CHIRPS, and introduces the reader to the vehicle design with focus on the use of radioisotope thermoelectric generator (RTG) technology as the primary heat (1 kW total) and power source for the robotic vehicle. Radioisotope heater unit (RHU) milli-watt power systems (120 mW total) are also employed to power the mini-radiowave ice transceivers, which are used to relay data through the ice up to the surface lander. The results of modeling and design work for both of these areas are discussed in this paper. Although radioisotope power is baselined for the Europa flight version of the cyrobot, no decision on the final design of the cryobot will be made until the environmental review process is complete. Any use of the cryobot for Mars or Europa will conform to all environmental and planetary protection requirements. .

  2. Milliwatt radioisotope power supply for the PASCAL Mars surface stations

    Science.gov (United States)

    Allen, Daniel T.; Murbach, Marcus S.

    2001-02-01

    A milliwatt power supply is being developed based on the 1 watt Light-Weight Radioisotope Heater Unit (RHU), which has already been used to provide heating alone on numerous spacecraft. In the past year the power supply has been integrated into the design of the proposed PASCAL Mars Network Mission, which is intended to place 24 surface climate monitoring stations on Mars. The PASCAL Mars mission calls for the individual surface stations to be transported together in one spacecraft on a trajectory direct from launch to orbit around Mars. From orbit around Mars each surface station will be deployed on a SCRAMP (slotted compression ramp) probe and, after aerodynamic and parachute deceleration, land at a preselected location on the planet. During descent sounding data and still images will be accumulated, and, once on the surface, the station will take measurements of pressure, temperature and overhead atmospheric optical depth for a period of 10 Mars years (18.8 Earth years). Power for periodic data acquisition and transmission to orbital then to Earth relay will come from a bank of ultracapacitors which will be continuously recharged by the radioisotope power supply. This electronic system has been designed and a breadboard built. In the ultimate design the electronics will be arrayed on the exterior surface of the radioisotope power supply in order to take advantage of the reject heat. This assembly in turn is packaged within the SCRAMP, and that assembly comprises the surface station. An electrically heated but otherwise prototypical power supply was operated in combination with the surface station breadboard system, which included the ultracapacitors. Other issues addressed in this work have been the capability of the generator to withstand the mechanical shock of the landing on Mars and the effectiveness of the generator's multi-foil vacuum thermal insulation. .

  3. A new access control system by fingerprint for radioisotope facilities

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Hiroko; Hirata, Yasuki [Kyushu Univ., Fukuoka (Japan). Radioisotope Center; Kondo, Takahiro; Takatsuki, Katsuhiro

    1998-04-01

    We applied a new fingerprint checker for complete access control to the radiation controlled area and to the radioisotope storage room, and prepared softwares for the best use of this checker. This system consists of a personal computer, access controllers, a fingerprint register, fingerprint checkers, a tenkey and mat sensors, permits ten thousand users to register their fingerprints and its hard disk to keep more than a million records of user`s access. Only 1% of users could not register their fingerprints worn-out, registered four numbers for a fingerprint. The softwares automatically provide varieties of reports, caused a large reduction in manual works. (author)

  4. Lightweight Radioisotope Heater Unit (LWRHU) production for the Cassini mission

    Energy Technology Data Exchange (ETDEWEB)

    Rinehart, G.H.

    1996-06-01

    The Lightweight Radioisotope Heater Unit (LWRHU) is a {sup 238}PuO{sub 2} fueled heat source designed to provide a thermal watt of power for space missions. The LWRHU will be used to maintain the temperature of various components on the spacecraft at the required level. The heat source consists of a {sup 238}PuO{sub 2} fuel pellet, a Pt-30Rh capsule, a pyrolytic graphite insulator, and a woven graphite aeroshell assembly. Los Alamos has fabricated 180 heater units, which will be used on the Cassini mission. This report summarizes the specifications, fabrication processes, and production data for the heat sources fabricated at Los Alamos.

  5. ADVANCED RADIOISOTOPE HEAT SOURCE AND PROPULSION SYSTEMS FOR PLANETARY EXPLORATION

    Energy Technology Data Exchange (ETDEWEB)

    R. C. O' Brien; S. D. Howe; J. E. Werner

    2010-09-01

    The exploration of planetary surfaces and atmospheres may be enhanced by increasing the range and mobility of a science platform. Fundamentally, power production and availability of resources are limiting factors that must be considered for all science and exploration missions. A novel power and propulsion system is considered and discussed with reference to a long-range Mars surface exploration mission with in-situ resource utilization. Significance to applications such as sample return missions is also considered. Key material selections for radioisotope encapsulation techniques are presented.

  6. Parametric System Model for a Stirling Radioisotope Generator

    Science.gov (United States)

    Schmitz, Paul C.

    2015-01-01

    A Parametric System Model (PSM) was created in order to explore conceptual designs, the impact of component changes and power level on the performance of the Stirling Radioisotope Generator (SRG). Using the General Purpose Heat Source (GPHS approximately 250 Wth) modules as the thermal building block from which a SRG is conceptualized, trade studies are performed to understand the importance of individual component scaling on isotope usage. Mathematical relationships based on heat and power throughput, temperature, mass, and volume were developed for each of the required subsystems. The PSM uses these relationships to perform component- and system-level trades.

  7. REVISS / MAYAK: A new partnership in radioisotope supply

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, N. [REVISS Services Limited, Chesham (United Kingdom); Chikshov, A.I.; Malykh, Y.A. [MAYAK Production Association, Ozyorsk (Russian Federation)

    1997-10-01

    REVISS Services (UK) Limited, the joint venture company formed between Amersham International plc, Production Association MAYAK and Techsnabexport brings together the scientific, manufacturing, marketing and distribution skills and facilities which enable REVISS to be not just a major supplier of radioisotopes and other associated products and services, but the supplier with the largest product range. The paper describes the history and the development of MAYAK and reviews its manufacturing facilities and capabilities and also how MAYAK has moved from being a secret military organisation to become a major and successful commercial organisation

  8. Energy-Recovery Linacs for Commercial Radioisotope Production

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Rolland Paul [Muplus, Inc., Newport News, VA (United States)

    2016-11-19

    Most radioisotopes are produced by nuclear reactors or positive ion accelerators, which are expensive to construct and to operate. Photonuclear reactions using bremsstrahlung photon beams from less-expensive electron linacs can generate isotopes of critical interest, but much of the beam energy in a conventional electron linac is dumped at high energy, making unwanted radioactivation. The largest part of this radioactivation may be completely eliminated by applying energy recovery linac technology to the problem with an additional benefit that the energy cost to produce a given amount of isotope is reduced. Consequently a Superconducting Radio Frequency (SRF) Energy Recovery Linac (ERL) is a path to a more diverse and reliable domestic supply of short-lived, high-value, high-demand isotopes at a cost lower than that of isotopes produced by reactors or positive-ion accelerators. A Jefferson Lab approach to this problem involves a thin photon production radiator, which allows the electron beam to recirculate through rf cavities so the beam energy can be recovered while the spent electrons are extracted and absorbed at a low enough energy to minimize unwanted radioactivation. The thicker isotope photoproduction target is not in the beam. MuPlus, with Jefferson Lab and Niowave, proposed to extend this ERL technology to the commercial world of radioisotope production. In Phase I we demonstrated that 1) the ERL advantage for producing radioisotopes is at high energies (~100 MeV), 2) the range of acceptable radiator thickness is narrow (too thin and there is no advantage relative to other methods and too thick means energy recovery is too difficult), 3) using optics techniques developed under an earlier STTR for collider low beta designs greatly improves the fraction of beam energy that can be recovered (patent pending), 4) many potentially useful radioisotopes can be made with this ERL technique that have never before been available in significant commercial quantities

  9. GEANT4 simulation of cyclotron radioisotope production in a solid target.

    Science.gov (United States)

    Poignant, F; Penfold, S; Asp, J; Takhar, P; Jackson, P

    2016-05-01

    The use of radioisotopes in nuclear medicine is essential for diagnosing and treating cancer. The optimization of their production is a key factor in maximizing the production yield and minimizing the associated costs. An efficient approach to this problem is the use of Monte Carlo simulations prior to experimentation. By predicting isotopes yields, one can study the isotope of interest expected activity for different energy ranges. One can also study the target contamination with other radioisotopes, especially undesired radioisotopes of the wanted chemical element which are difficult to separate from the irradiated target and might result in increasing the dose when delivering the radiopharmaceutical product to the patient. The aim of this work is to build and validate a Monte Carlo simulation platform using the GEANT4 toolkit to model the solid target system of the South Australian Health and Medical Research Institute (SAHMRI) GE Healthcare PETtrace cyclotron. It includes a GEANT4 Graphical User Interface (GUI) where the user can modify simulation parameters such as the energy, shape and current of the proton beam, the target geometry and material, the foil geometry and material and the time of irradiation. The paper describes the simulation and presents a comparison of simulated and experimental/theoretical yields for various nuclear reactions on an enriched nickel 64 target using the GEANT4 physics model QGSP_BIC_AllHP, a model recently developed to evaluate with high precision the interaction of protons with energies below 200MeV available in Geant4 version 10.1. The simulation yield of the (64)Ni(p,n)(64)Cu reaction was found to be 7.67±0.074 mCi·μA(-1) for a target energy range of 9-12MeV. Szelecsenyi et al. (1993) gives a theoretical yield of 6.71mCi·μA(-1) and an experimental yield of 6.38mCi·μA(-1). The (64)Ni(p,n)(64)Cu cross section obtained with the simulation was also verified against the yield predicted from the nuclear database TENDL and

  10. Carbon-carbon bond cleavage of 1,2-hydroxy ethers b7 vanadium(V) dipicolinate complexes

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Susan K [Los Alamos National Laboratory; Gordon, John C [Los Alamos National Laboratory; Thorn, David L [Los Alamos National Laboratory; Scott, Brian L [Los Alamos National Laboratory; Baker, R Tom [Los Alamos National Laboratory

    2009-01-01

    The development of alternatives to current petroleum-based fuels and chemicals is becoming increasingly important due to concerns over climate change, growing world energy demand, and energy security issues. Using non-food derived biomass to produce renewable feedstocks for chemicals and fuels is a particularly attractive possibility. However, the majority of biomass is in the form of lignocellulose, which is often not fully utilized due to difficulties associated with breaking down both lignin and cellulose. Recently, a number of methods have been reported to transform cellulose directly into more valuable materials such as glucose, sorbitol, 5-(chloromethyl)furfural, and ethylene glycol. Less progress has been made with selective transformations of lignin, which is typically treated in paper and forest industries by kraft pulping (sodium hydroxide/sodium sulfide) or incineration. Our group has begun investigating aerobic oxidative C-C bond cleavage catalyzed by dipicolinate vanadium complexes, with the idea that a selective C-C cleavage reaction of this type could be used to produce valuable chemicals or intermediates from cellulose or lignin. Lignin is a randomized polymer containing methoxylated phenoxy propanol units. A number of different linkages occur naturally; one of the most prevalent is the {beta}-O-4 linkage shown in Figure 1, containing a C-C bond with 1,2-hydroxy ether substituents. While the oxidative C-C bond cleavage of 1,2-diols has been reported for a number of metals, including vanadium, iron, manganese, ruthenium, and polyoxometalate complexes, C-C bond cleavage of 1,2-hydroxy ethers is much less common. We report herein vanadium-mediated cleavage of C-C bonds between alcohol and ether functionalities in several lignin model complexes. In order to explore the scope and potential of vanadium complexes to effect oxidative C-C bond cleavage in 1,2-hydroxy ethers, we examined the reactivity of the lignin model complexes pinacol monomethyl ether (A

  11. Semi-Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Program Tasks for April 1, 2002 Through September 20, 2002

    Energy Technology Data Exchange (ETDEWEB)

    Moore, J.P.

    2002-12-03

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. For the Cassini Mission, for example, ORNL was involved in the production of carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS). This report has been divided into three sections to reflect program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2002. The first section deals primarily with maintenance of the capability to produce flight quality (FQ) CBCF insulator sets, iridium alloy blanks and foil, and CVS. In all three cases, production maintenance is assured by the manufacture of limited quantities of FQ components. The second section deals with several technology activities to improve the manufacturing processes, characterize materials, or to develop technologies for new radioisotope power systems. The last section is dedicated to studies related to the production of {sup 238}Pu.

  12. Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Tasks for October 1, 2003 through September 30, 2004

    Energy Technology Data Exchange (ETDEWEB)

    None listed

    2005-06-01

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2004. Production and production maintenance activities for flight quality (FQ) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. In all three cases, production maintenance is assured by the manufacture of limited quantities of FQ components. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.

  13. Semi-Annual Technical Progress Report of the Radioisotope Power System Materials Production and Technology Program Tasks for September 2000 through March 2001

    Energy Technology Data Exchange (ETDEWEB)

    Moore, J.P.

    2001-05-22

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. For the Cassini Mission, for example, ORNL was involved in the production of carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) and weld shields (WS). This report has been divided into three sections to reflect program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2001. The first section deals primarily with maintenance of the capability to produce flight quality (FQ) CBCF insulator sets, iridium alloy blanks and foil, CVS, and WS. In all three cases, production maintenance is assured by the manufacture of limited quantities of FQ components. The second section deals with several technology activities to improve the manufacturing processes, characterize materials. or to develop technologies for new radioisotope power systems. The last section is dedicated to studies related to the production of {sup 238}Pu.

  14. Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Program Tasks for October 1, 2002 Through September 30, 2003

    Energy Technology Data Exchange (ETDEWEB)

    King, J.F.

    2004-05-18

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. For the Cassini Mission, for example, ORNL was involved in the production of carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS). This report has been divided into three sections to reflect program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2003. The first section deals primarily with maintenance of the capability to produce flight quality (FQ) CBCF insulator sets, iridium alloy blanks and foil, and CVS. In all three cases, production maintenance is assured by the manufacture of limited quantities of FQ components. The second section deals with several technology activities to improve the manufacturing processes, characterize materials, or to develop technologies for new radioisotope power systems. The last section is dedicated to studies related to the production of {sup 238}Pu.

  15. ANNUAL TECHNICAL PROGRESS REPORT OF RADIOISOTOPE POWER SYSTEMS MATERIALS PRODUCTION AND TECHNOLOGY PROGRAM TASKS FOR OCTOBER 1, 2010 THROUGH SEPTEMBER 30, 2011

    Energy Technology Data Exchange (ETDEWEB)

    King, James F [ORNL

    2012-05-01

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration (NASA) for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, the Oak Ridge National Laboratory (ORNL) produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. These components were also produced for the Pluto New Horizons and Mars Science Lab missions launched in January 2006 and November 2011respectively. The ORNL has been involved in developing materials and technology and producing components for the DOE for nearly four decades. This report reflects program guidance from the Office of RPS for fiscal year (FY) 2011. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new RPS. Work has also been initiated to establish fabrication capabilities for the Light Weight Radioisotope Heater Units.

  16. Annual Technical Progress Report of Radioisotope Power System Materials Production and Technical Program Tasks for October 1, 2005 through September 30, 2006

    Energy Technology Data Exchange (ETDEWEB)

    None

    2007-04-02

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2006. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.

  17. ANNUAL TECHNICAL PROGRESS REPORT OF RADIOISOTOPE POWER SYSTEM MATERIALS PRODUCTION AND TECHNOLOGY PROGRAM TASKS FOR OCTOBER 1, 2005 THROUGH SEPTEMBER 30, 2006

    Energy Technology Data Exchange (ETDEWEB)

    King, James F [ORNL

    2007-04-01

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2006. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.

  18. Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Programs Tasks for October 1, 2005, through September 30, 2006

    Energy Technology Data Exchange (ETDEWEB)

    None

    2006-09-30

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2006. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.

  19. ANNUAL TECHNICAL PROGRESS REPORT OF RADIOISOTOPE POWER SYSTEM MATERIALS PRODUCTION AND TECHNOLOGY PROGRAM TASKS FOR OCTOBER 1, 2004, THROUGH SEPTEMBER 30, 2005

    Energy Technology Data Exchange (ETDEWEB)

    None

    2005-09-30

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2005. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.

  20. Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Tasks for October 1, 2004 through September 30, 2005

    Energy Technology Data Exchange (ETDEWEB)

    None listed

    2006-08-03

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2005. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.

  1. Annual Technical Progress Report of Radioisotope Power System Materials Production and Technology Program Tasks for October 1, 2004 Through September 30, 2005

    Energy Technology Data Exchange (ETDEWEB)

    King, James F [ORNL

    2006-06-01

    The Office of Space and Defense Power Systems of the Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators were supplied by the DOE to the National Aeronautics and Space Administration for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, ORNL produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. The Oak Ridge National Laboratory (ORNL) has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2005. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new radioisotope power systems.

  2. G64-12 and G64-37 Are Carbon-enhanced Metal-poor Stars

    Science.gov (United States)

    Placco, Vinicius M.; Beers, Timothy C.; Reggiani, Henrique; Meléndez, Jorge

    2016-10-01

    We present new high-resolution chemical-abundance analyses for the well-known high proper-motion subdwarfs G64-12 and G64-37, based on very high signal-to-noise ratio spectra ({{S}}/{{N}}˜ 700/1) with resolving power R ˜ 95,000. These high-quality data enable the first reliable determination of the carbon abundances for these two stars; we classify them as carbon-enhanced metal-poor (CEMP) stars based on their carboni cities, which both exceed [C/Fe] = +1.0. They are sub-classified as CEMP-no Group-II stars, based on their location in the Yoon-Beers diagram of absolute carbon abundance, A(C) versus [Fe/H], as well as on the conventional diagnostic [Ba/Fe]. The relatively low absolute carbon abundances of CEMP-no stars, in combination with the high effective temperatures of these two stars ({T}{eff}˜ 6500 {{K}}), weakens their CH molecular features to the point that accurate carbon abundances can only be estimated from spectra with very high S/N. A comparison of the observed abundance patterns with the predicted yields from massive, metal-free supernova models reduces the inferred progenitor masses by factors of ˜2-3, and explosion energies by factors of ˜10-15, compared to those derived using previously claimed carbon-abundance estimates. There are certainly many more warm CEMP-no stars near the halo main-sequence turnoff that have been overlooked in past studies, directly impacting the derived frequencies of CEMP-no stars as a function of metallicity, a probe that provides important constraints on Galactic chemical evolution models, the initial mass function in the early universe, and first-star nucleosynthesis.

  3. Operational Readiness Review Plan for the Radioisotope Thermoelectric Generator Materials Production Tasks

    Science.gov (United States)

    Cooper, R. H.; Martin, M. M.; Riggs, C. R.; Beatty, R. L.; Ohriner, E. K.; Escher, R. N.

    1990-04-19

    In October 1989, a US shuttle lifted off from Cape Kennedy carrying the spacecraft Galileo on its mission to Jupiter. In November 1990, a second spacecraft, Ulysses, will be launched from Cape Kennedy with a mission to study the polar regions of the sun. The prime source of power for both spacecraft is a series of radioisotope thermoelectric generators (RTGs), which use plutonium oxide (plutonia) as a heat source. Several of the key components in this power system are required to ensure the safety of both the public and the environment and were manufactured at Oak Ridge National Laboratory (ORNL) in the 1980 to 1983 period. For these two missions, Martin Marietta Energy Systems, Inc. (Energy Systems), will provide an iridium alloy component used to contain the plutonia heat source and a carbon composite material that serves as a thermal insulator. ORNL alone will continue to fabricate the carbon composite material. Because of the importance to DOE that Energy Systems deliver these high quality components on time, performance of an Operational Readiness Review (ORR) of these manufacturing activities is necessary. Energy Systems Policy GP 24 entitled "Operational Readiness Process" describes the formal and comprehensive process by which appropriate Energy Systems activities are to be reviewed to ensure their readiness. This Energy System policy is aimed at reducing the risks associated with mission success and requires a management approved "readiness plan" to be issued. This document is the readiness plan for the RTG materials production tasks.

  4. Sodium Variable Conductance Heat Pipe for Radioisotope Stirling Systems

    Science.gov (United States)

    Tarau, Calin; Anderson, William G.; Walker, Kara

    2009-01-01

    In a Stirling radioisotope system, heat must continually be removed from the General Purpose Heat Source (GPHS) modules to maintain the modules and surrounding insulation at acceptable temperatures. Normally, the Stirling convertor provides this cooling. If the converter stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, and also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) has been designed to allow multiple stops and restarts of the Stirling convertor in an Advanced Stirling Radioisotope Generator (ASRG). When the Stirling convertor is turned off, the VCHP will activate when the temperatures rises 30 C above the setpoint temperature. A prototype VCHP with sodium as the working fluid was fabricated and tested in both gravity aided and against gravity conditions for a nominal heater head temperature of 790 C. The results show very good agreement with the predictions and validate the model. The gas front was located at the exit of the reservoir when heater head temperature was 790 C while cooling was ON, simulating an operating Advanced Stirling Converter (ASC). When cooling stopped, the temperature increased by 30 C, allowing the gas front to move past the radiator, which transferred the heat to the case. After resuming the cooling flow, the front returned at the initial location turning OFF the VCHP. The against gravity working conditions showed a colder reservoir and faster transients.

  5. Radioisotope Electric Propulsion for Deep Space Sample Return

    Energy Technology Data Exchange (ETDEWEB)

    Noble, Robert J.; /SLAC

    2009-07-14

    The need to answer basic questions regarding the origin of the Solar System will motivate robotic sample return missions to destinations like Pluto, its satellite Charon, and objects in the Kuiper belt. To keep the mission duration short enough to be of interest, sample return from objects farther out in the Solar System requires increasingly higher return velocities. A sample return mission involves several complicated steps to reach an object and obtain a sample, but only the interplanetary return phase of the mission is addressed in this paper. Radioisotope electric propulsion is explored in this parametric study as a means to propel small, dedicated return vehicles for transferring kilogram-size samples from deep space to Earth. Return times for both Earth orbital rendezvous and faster, direct atmospheric re-entry trajectories are calculated for objects as far away as 100 AU. Chemical retro-rocket braking at Earth is compared to radioisotope electric propulsion but the limited deceleration capability of chemical rockets forces the return trajectories to be much slower.

  6. Heat Transfer Analysis for Optimal Design of Radioisotope Thermoelectric Generator

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Han; Son, Kwang Jae; Hong, Jintae; Kim, Jong Bum [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    A new approach is need in the space development and requires a technique having a high degree of reliability. For example, there is radioisotope thermoelectric generator(RTG) using radioisotope that has different mechanism in comparison with solar power as power source. This is a technology that has already been trusted by generator for space in the developed countries. For example, RTG is essential for moon explorer because no other power exist source night of moon. In this study, we investigated the thermal efficiency according to the structure of RTG. Specifically, the thermal properties were analyzed according to the presence of the shield inside vacuum heat-insulating part of the RTG through the finite element analysis. Finite element analysis was used to analyze the characteristics of the temperature distribution in the RTG models according to the shield. The structure of the shield came out less heat loss than the structure without shield. As a result, the structure with a shield is advantage in the RTG design.

  7. Characterization of the Advanced Stirling Radioisotope Generator Engineering Unit 2

    Science.gov (United States)

    Lewandowski, Edward J.; Oriti, Salvatore M.; Schifer, Niholas A.

    2016-01-01

    Significant progress was made developing the Advanced Stirling Radioisotope Generator (ASRG) 140-W radioisotope power system. While the ASRG flight development project has ended, the hardware that was designed and built under the project is continuing to be tested to support future Stirling-based power system development. NASA Glenn Research Center recently completed the assembly of the ASRG Engineering Unit 2 (EU2). The ASRG EU2 consists of the first pair of Sunpower's Advanced Stirling Convertor E3 (ASC-E3) Stirling convertors mounted in an aluminum housing, and Lockheed Martin's Engineering Development Unit (EDU) 4 controller (a fourth-generation controller). The ASC-E3 convertors and Generator Housing Assembly (GHA) closely match the intended ASRG Qualification Unit flight design. A series of tests were conducted to characterize the EU2, its controller, and the convertors in the flight-like GHA. The GHA contained an argon cover gas for these tests. The tests included measurement of convertor, controller, and generator performance and efficiency; quantification of control authority of the controller; disturbance force measurement with varying piston phase and piston amplitude; and measurement of the effect of spacecraft direct current (DC) bus voltage on EU2 performance. The results of these tests are discussed and summarized, providing a basic understanding of EU2 characteristics and the performance and capability of the EDU 4 controller.

  8. Characterization of the Advanced Stirling Radioisotope Generator EU2

    Science.gov (United States)

    Lewandowski, Edward J.; Oriti, Salvatore M.; Schifer, Nicholas A.

    2015-01-01

    Significant progress was made developing the Advanced Stirling Radioisotope Generator (ASRG), a 140-watt radioisotope power system. While the ASRG flight development project has ended, the hardware that was designed and built under the project is continuing to be tested to support future Stirling-based power system development. NASA GRC recently completed the assembly of the ASRG Engineering Unit 2 (EU2). The ASRG EU2 consists of the first pair of Sunpower's ASC-E3 Stirling convertors mounted in an aluminum housing, and Lockheed Martin's Engineering Development Unit (EDU) 4 controller (a fourth generation controller). The ASC-E3 convertors and Generator Housing Assembly (GHA) closely match the intended ASRG Qualification Unit flight design. A series of tests were conducted to characterize the EU2, its controller, and the convertors in the flight-like GHA. The GHA contained an argon cover gas for these tests. The tests included: measurement of convertor, controller, and generator performance and efficiency, quantification of control authority of the controller, disturbance force measurement with varying piston phase and piston amplitude, and measurement of the effect of spacecraft DC bus voltage on EU2 performance. The results of these tests are discussed and summarized, providing a basic understanding of EU2 characteristics and the performance and capability of the EDU 4 controller.

  9. Radioisotope Thermoelectric Generator Options for Pluto Fast Flyby Mission

    Science.gov (United States)

    Schock, Alfred

    1994-07-01

    A small spacecraft design for the Pluto Fast Flyby (PFF) mission is under study by the Jet Propulsion Laboratory (PL) for the National Aeronautics and Space Administration (NASA), for a possible launch as early as 1998. JPL's 1992 baseline design calls for a power source able to furnish an energy output of 3963 kWh and a power output of 69 Watts(e) at the end of the 9.2-year mission. Satisfying those demands is made difficult because NASA management has set a goal of reducing the spacecraft mass from a baseline value of 166 kg to ~110 kg, which implies a mass goal of less than 10 kg for the power source. To support the ongoing NASA/JPL studies, the Department of Energy's Office of Special Applications (DOE/OSA) commissioned Fairchild Space to prepare and analyze conceptual designs of radioisotope power systems for the PFF mission. Thus far, a total of eight options employing essentially the same radioisotope heat source modules were designed and subjected to thermal, electrical, structural, and mass analyses by Fairchild. Five of these - employing thermoelectric converters - are described in the present paper, and three - employing free-piston Stirling converters - are described in the companion paper presented next. The system masses of the thermoelectric options ranged from 19.3 kg to 10.2 kg. In general, the options requiring least development are the heaviest, and the lighter options require more development with greater programmatic risk.

  10. Multi-Watt Small Radioisotope Thermoelectric Generator Conceptual Design Study

    Science.gov (United States)

    Determan, William R.; Otting, William; Frye, Patrick; Abelson, Robert; Ewell, Richard; Miyake, Bob; Synder, Jeff

    2007-01-01

    A need has been identified for a small, light-weight, reliable power source using a radioisotope heat source, to power the next generation of NASA's small surface rovers and exploration probes. Unit performance, development costs, and technical risk are key criteria to be used to select the best design approach. Because safety can be a major program cost and schedule driver, RTG designs should utilize the DOE radioisotope safety program's data base to the maximum extent possible. Other aspects important to the conceptual design include: 1) a multi-mission capable design for atmospheric and vacuum environments, 2) a module size based on one GPHS Step 2 module, 3) use of flight proven thermoelectric converter technologies, 4) a long service lifetime of up to 14 years, 5) maximize unit specific power consistent with all other requirements, and 6) be ready by 2013. Another critical aspect of the design is the thermal integration of the RTG with the rover or probe's heat rejection subsystem and the descent vehicle's heat rejection subsystem. This paper describes two multi-watt RTG design concepts and their integration with a MER-class rover.

  11. The radioisotope osteogram: Kinetic studies of skeletal disorders in humans

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, N.S.

    1959-10-16

    Radioactive strontium can serve as a tracer to gain information concerning calcium metabolism in human subjects. Gamma-emitting Sr{sup 85} is used rather than the much more hazardous, beta-emitting Sr{sup 89} and Sr{sup 90}. (ca{sup 47} -- the ideal tracer for normal calcium -- is quite expensive and difficult to procure.) Very significant information may be obtained merely by measuring and recording the changes in radioactivity in various body areas during the first hour after intravenous injection of the bone-seeking radioisotope. This is accomplished by placing a lead-shielded gamma-scintillation detector in contact with the skin over the sites of interest and recording the activities on a scaler or ratemeter. The activity versus time curves so obtained are called radioisotope osteograms. Data were presented which indicated that Sr{sup 85} osteograms for patients afflicted with osteoporosis, Paget`s disease, tumor metastases to bone, and possibly multiple myeloma, differ significantly from those obtained from subjects with no skeletal abnormalities. Some interpretations of these deviations were discussed. The value of conducting double-tracer tests (e.g. -- Sr{sup 85} plus radio-iodinated serum albumin) was demonstrated, and correlations with excretion data were made. With further refinements the technique may ultimately become useful for certain diagnostic problems in the clinic and.for evaluating the efficacy of treatment of these disorders.

  12. GRC Supporting Technology for NASA's Advanced Stirling Radioisotope Generator (ASRG)

    Science.gov (United States)

    Schreiber, Jeffrey G.; Thieme, Lanny G.

    2008-01-01

    From 1999 to 2006, the NASA Glenn Research Center (GRC) supported a NASA project to develop a high-efficiency, nominal 110-We Stirling Radioisotope Generator (SRG110) for potential use on NASA missions. Lockheed Martin was selected as the System Integration Contractor for the SRG110, under contract to the Department of Energy (DOE). The potential applications included deep space missions, and Mars rovers. The project was redirected in 2006 to make use of the Advanced Stirling Convertor (ASC) that was being developed by Sunpower, Inc. under contract to GRC, which would reduce the mass of the generator and increase the power output. This change would approximately double the specific power and result in the Advanced Stirling Radioisotope Generator (ASRG). The SRG110 supporting technology effort at GRC was replanned to support the integration of the Sunpower convertor and the ASRG. This paper describes the ASRG supporting technology effort at GRC and provides details of the contributions in some of the key areas. The GRC tasks include convertor extended-operation testing in air and in thermal vacuum environments, heater head life assessment, materials studies, permanent magnet characterization and aging tests, structural dynamics testing, electromagnetic interference and electromagnetic compatibility characterization, evaluation of organic materials, reliability studies, and analysis to support controller development.

  13. Search for neutral Higgs bosons decaying to tau pairs in p anti-p collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Agelou, M.; Agram, J.-L.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; /Buenos Aires U. /Rio de

    2006-05-01

    A search for the production of neutral Higgs bosons {Phi} decaying into {tau}{sup +}{tau}{sup -} final states in p{bar p} collisions at a center-of-mass energy of 1.96 TeV is presented. The data, corresponding to an integrated luminosity of approximately 325 pb{sup -1}, were collected by the D0 experiment at the Fermilab Tevatron Collider. Since no excess compared to the expectation from standard model processes is found, limits on the production cross section times branching ratio are set. The results are combined with those obtained from the D0 search for {Phi}b({bar b}) {yields} b{bar b}b({bar b}) and are interpreted in the minimal supersymmetric standard model.

  14. Search for high-mass resonances decaying to e mu in p anti-p collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G.; Ambrose, D.; Amerio, S.; Amidei, D.; Anastassov, A.; Anikeev, K.; /Taiwan, Inst.

    2006-03-01

    The authors describe a general search for resonances decaying to a neutral e{mu} final state in p{bar p} collisions at a center-of-mass energy of 1.96 TeV. Using a data sample representing 344 pb{sup -1} of integrated luminosity recorded by the CDF II experiment, they compare Standard Model predictions with the number of observed events for invariant masses between 50 and 800 GeV/c{sup 2}. Finding no significant excess (5 events observed vs. 7.7 {+-} 0.8 expected for M{sub e{mu}} > 100 GeV/c{sup 2}), they set limits on sneutrino and Z{prime} masses as functions of lepton family number violating couplings.

  15. The effect of an electrically conductive carbon nanotube/collagen composite on neurite outgrowth of PC12 cells.

    Science.gov (United States)

    Cho, Youngnam; Borgens, Richard Ben

    2010-11-01

    We report the preparation of an electrically conductive composite composed of collagen and carbon nanotubes (CNTs) and its use as a substrate for the in vitro growth of PC12 cells. Morphological observation by scanning electron microscopy (SEM) indicated the homogenous dispersion of CNTs in the collagen matrix. Four-point probe and cyclic voltammogram studies demonstrated the enhanced electroactivity and a lowered electrical resistivity of the resulting composites even at low loadings (collagen matrix. SEM and immunofluorescent images have indicated that the morphological features of PC12 cells were dominantly influenced by electrical potential. Greater neurite extension was preferentially induced on the exposure of electrical stimulation by facilitating the differentiation of PC12 cells into neurons indicated by more significant filopodium extension. These electrically conductive, biocompatible CNT/collagen composites could be of benefit for the development of novel neural electrodes, enhancing the growth, differentiation, and branching of neurons in an electrically driven way.

  16. 77 FR 21592 - Guidelines for Preparing and Reviewing Licensing Applications for the Production of Radioisotopes

    Science.gov (United States)

    2012-04-10

    ... Chapters 7-18 of Draft Interim Staff Guidance (ISG) NPR-ISG-2011-002, augmenting NUREG-1537, Part 1... Content,'' for the production of radioisotopes and NUREG-1537, Part 2, ``Guidelines for Preparing and...,'' for the production of radioisotopes. The ISG augmenting NUREG-1537, Parts 1 & 2, Chapters 1-6...

  17. First collinear laser spectroscopy measurements of radioisotopes from an IGISOL ion source

    NARCIS (Netherlands)

    Billowes, J; Campbell, P; Cochrane, ECA; Cooke, JL; Dendooven, P; Evans, DE; Grant, IS; Griffith, JAR; Honkanen, A; Huhta, M; Levins, JMG; Liukkonen, E; Oinonen, M; Pearson, MR; Penttila, H; Persson, B.L.; Richardson, DS; Tungate, G; Wheeler, P; Zybert, L; Aysto, J

    1997-01-01

    The standard Doppler-free technique of collinear laser spectroscopy has been successfully applied to radioisotopes from the ion-guide isotope separator (IGISOL) at the Universiry of Jyvaskyla. The laser resonance fluorescence signals for the Ba-140.142,Ba-144 radioisotopes show that the ion beam ene

  18. Carbon sequestration in surface flow constructed wetland after 12 years of swine wastewater treatment

    Science.gov (United States)

    Constructed wetlands used for the treatment of swine wastewater may potentially sequester significant amounts of carbon. In past studies, we evaluated the treatment efficiency of wastewater in marsh-pond-marsh design wetland system. The functionality of this system was highly dependent on soil carbo...

  19. Carbon sequestration in a surface flow constructed wetland after 12 years of swine wastewater treatment.

    Science.gov (United States)

    Reddy, Gudigopuram B; Raczkowski, Charles W; Cyrus, Johnsely S; Szogi, Ariel

    2016-01-01

    Constructed wetlands used for the treatment of swine wastewater may potentially sequester significant amounts of carbon. In past studies, we evaluated the treatment efficiency of wastewater in a marsh-pond-marsh design wetland system. The functionality of this system was highly dependent on soil carbon content and organic matter turnover rate. To better understand system performance and carbon dynamics, we measured plant dry matter, decomposition rates and soil carbon fractions. Plant litter decomposition rate was 0.0052 g day(-1) (±0.00119 g day(-1)) with an estimated half-life of 133 days. The detritus layer accumulated over the soil surface had much more humin than other C fractions. In marsh areas, soil C extracted with NaOH had four to six times higher amounts of humic acid, fulvic acid and humin than soil C extracted by cold and hot water, HCl/HF, and Na pyruvate. In the pond area, humic acid, fulvic acid and humin content were two to four times lower than in the marsh area. More soil C and N was found in the marsh area than in the pond area. These wetlands proved to be large sinks for stable C forms.

  20. A small low energy cyclotron for radioisotope measurements

    Energy Technology Data Exchange (ETDEWEB)

    Bertsche, K.J.

    1989-11-01

    Direct detection of {sup 14}C by accelerator mass spectrometry has proved to be a much more sensitive method for radiocarbon dating than the decay counting method invented earlier by Libby. A small cyclotron (the cyclotrino'') was proposed for direct detection of radiocarbon in 1980. This combined the suppression of background through the use of negative ions, which had been used effectively in tandem accelerators, with the high intrinsic mass resolution of a cyclotron. Development of a small electrostatically-focused cyclotron for use as a mass spectrometer was previously reported but the sensitivity needed for detection of {sup 14}C at natural abundance was not achieved. The major contributions of this work are the integration of a high current external ion source with a small flat-field, electrostatically-focused cyclotron to comprise a system capable of measuring {sup 14}C at natural levels, and the analysis of ion motion in such a cyclotron, including a detailed analysis of phase bunching and its effect on mass resolution. A high current cesium sputter negative ion source generates a beam of carbon ions which is pre-separated with a Wien filter and is transported to the cyclotron via a series of electrostatic lenses. Beam is injected radially into the cyclotron using electrostatic deflectors and an electrostatic mirror. Axial focusing is entirely electrostatic. A microchannel plate detector is used with a phase-grated output. In its present form the system is capable of improving the sensitivity of detecting {sup 14}C in some biomedical experiments by a factor of 10{sup 4}. Modifications are discussed which could bring about an additional factor of 100 in sensitivity, which is important for archaeological and geological applications. Possibilities for measurements of other isotopes, such as {sup 3}H, and {sup 10}Be, and {sup 26}Al, are discussed. 70 refs.

  1. Plasma Polymerized Thin Films of Maleic Anhydride and 1,2-methylenedioxybenzene for Improving Adhesion to Carbon Surfaces

    DEFF Research Database (Denmark)

    Drews, Joanna Maria; Goutianos, Stergios; Kingshott, Peter

    2007-01-01

    Low power 2-phase AC plasma polymerization has been used to surface modify glassy carbon substrates that are used as an experimental model for carbon fibers in reinforced composites. In order to probe the role of carboxylic acid density on the interfacial adhesion strength a combination...... of different plasma powers and monomer compositions was used. Maleic anhydride (MAR) and 1,2-methylenedioxybenzene (MDOB) were plasma deposited separately and as mixtures to create layers with different surface compositions. In all cases the MAR was hydrolyzed to form carboxylic acid groups. Some carboxylic...... total veflectanc~ Fourier transform infrared spectroscopy. Atomic force microscopy was used to measure the thickness of the plasma films and to monitor the surface roughness for the different polymerization conditions. Finally, preliminary results of fracture energy measurements of the plasma modified...

  2. Active Radiation Level Measurement on New Laboratory Instrument for Evaluating the Antibacterial Activity of Radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Joh, Eunha; Park, Jang Guen [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    A disc method has been widely used to measure the antibacterial effect of chemical agents. However, it is difficult to measure the antibacterial effect of radioisotopes using a disc method. A disc method is a method for diffusing a drug by placing the drug containing disc on the medium. In this method, radioisotopes are diffused on the medium and it is difficult to measure the exact effect by radiation. Thus, new laboratory equipment needs to evaluate the antibacterial activity by the radioisotopes. In this study, we measured the radiation level of radioisotopes on a new laboratory instrument using a MCNP. A disc method has been widely used to measure the antibacterial effect of chemical agents. This method uses a drug diffusion system for the measurement of anti-bacterial antibiotics. To measure the antimicrobial activity of a radioisotope, a new type of laboratory instrument is necessary to prevent the drug from spreading. The radioisotopes are used to diagnose and treat cancer. However, studies for anti-biotical use have not progressed. The radiation of radioisotopes has the effect of killing bacteria. Before this study proceeds further, it is necessary to be able to measure the antimicrobial activity of the radioisotope easily in the laboratory. However, in this study, it was possible to measure the antimicrobial activity of the radioisotope in the laboratory using a new laboratory instrument. We intend to start evaluation studies of the antibacterial activity of specific radioisotopes. In addition, it will be possible to develop research to overcome diseases caused by bacteria in the future.

  3. Inorganic, radioisotopic and organic analysis of 241-AP-101 tank waste

    Energy Technology Data Exchange (ETDEWEB)

    SK Fiskum; PR Bredt; JA Campbell; LR Greenwood; OT Farmer; GJ Lumetta; GM Mong; RT Ratner; CZ Soderquist; RG Swoboda; MW Urie; JJ Wagner

    2000-06-28

    Battelle received five samples from Hanford waste tank 241-AP-101, taken at five different depths within the tank. No visible solids or organic layer were observed in the individual samples. Individual sample densities were measured, then the five samples were mixed together to provide a single composite. The composite was homogenized and representative sub-samples taken for inorganic, radioisotopic, and organic analysis. All analyses were performed on triplicate sub-samples of the composite material. The sample composite did not contain visible solids or an organic layer. A subsample held at 10 C for seven days formed no visible solids. The characterization of the 241-AP-101 composite samples included: (1) Inductively-coupled plasma spectrometry for Ag, Al, Ba, Bi, Ca, Cd, Cr, Cu, Fe, K, La, Mg, Mn, Na, Nd, Ni, P, Pb, Pd, Ru, Rh, Si, Sr, Ti, U, Zn, and Zr (Note: Although not specified in the test plan, As, B, Be, Co, Li, Mo, Sb, Se, Sn, Tl, V, W, and Y were also measured and reported for information only) (2) Radioisotopic analyses for total alpha and total beta activities, {sup 3}H, {sup 14}C, {sup 60}Co, {sup 79}Se, {sup 90}Sr, {sup 99}Tc as pertechnetate, {sup 106}Ru/Rh, {sup 125}Sb, {sup 134}Cs, {sup 137}Cs, {sup 152}Eu, {sup 154}Eu, {sup 155}Eu, {sup 238}Pu, {sup 239+240}Pu, {sup 241}Am, {sup 242}Cm, and {sup 243+244}Cm; (3) Inductively-coupled plasma mass spectrometry for {sup 237}Np, {sup 239}Pu, {sup 240}Pu, {sup 99}Tc, {sup 126}Sn, {sup 129}I, {sup 231}Pa, {sup 233}U, {sup 234}U, {sup 235}U, {sup 236}U, {sup 238}U, {sup 241}AMU, {sup 242}AMU, {sup 243}AMU, As, B, Be, Ce, Co, Cs, Eu, I, Li, Mo, Pr, Rb, Sb, Se, Ta, Te, Th, Tl, V, and W; (4) total U by kinetic phosphorescence analysis; (5) Ion chromatography for Cl, F, NO{sub 2}, NO{sub 3}, PO{sub 4}, SO{sub 4}, acetate, formate, oxalate, and citrate; (6) Density, inorganic carbon and organic carbon by two different methods, mercury, free hydroxide, ammonia, and cyanide. The 241-AP-101 composite met all

  4. Semileptonic Decays

    Energy Technology Data Exchange (ETDEWEB)

    Luth, Vera G.; /SLAC

    2012-10-02

    The following is an overview of the measurements of the CKM matrix elements |V{sub cb}| and |V{sub ub}| that are based on detailed studies of semileptonic B decays by the BABAR and Belle Collaborations and major advances in QCD calculations. In addition, a new and improved measurement of the ratios R(D{sup (*)}) = {Beta}({bar B} {yields} D{sup (*)}{tau}{sup -}{bar {nu}}{sub {tau}})/{Beta}({bar B} {yields} D{sup (*)}{ell}{sup -}{bar {nu}}{sub {ell}}) is presented. Here D{sup (*)} refers to a D or a D* meson and {ell} is either e or {mu}. The results, R(D) = 0.440 {+-} 0.058 {+-} 0.042 and R(D*) = 0.332 {+-} 0.024 {+-} 0.018, exceed the Standard Model expectations by 2.0{sigma} and 2.7{sigma}, respectively. Taken together, they disagree with these expectations at the 3.4{sigma} level. The excess of events cannot be explained by a charged Higgs boson in the type II two-Higgs-doublet model.

  5. THE INFLUENCE OF THE POROUS STRUCTURE OF LOCAL ACTIVATED CARBONS ON THE IMMOBILIZATION OF THE CONGO RED DYE AND VITAMIN B 12

    Directory of Open Access Journals (Sweden)

    N. Timbaliuc

    2013-06-01

    Full Text Available The adsorption properties of activated carbons, obtained from local raw materials (nut shells, peach and plum stones, towards Congo Red and vitamin B12 have been studied. The values of adsorption of these marker-substances are in direct correlation with the structural characteristics of the studied samples of activated carbons, in particular, with their mesopore volume.

  6. Utilizing Radioisotope Power System Waste Heat for Spacecraft Thermal Management

    Science.gov (United States)

    Pantano, David R.; Dottore, Frank; Tobery, E. Wayne; Geng, Steven M.; Schreiber, Jeffrey G.; Palko, Joseph L.

    2005-01-01

    An advantage of using a Radioisotope Power System (RPS) for deep space or planetary surface missions is the readily available waste heat, which can be used for a number of beneficial purposes including: maintaining electronic components within a controlled temperature range, warming propulsion tanks and mobility actuators, and maintaining liquid propellants above their freezing temperature. Previous missions using Radioisotope Thermoelectric Generators (RTGs) dissipated large quantities of waste heat due to the low efficiency of the thermoelectric conversion technology. The next generation RPSs, such as the 110-Watt Stirling Radioisotope Generator (SRG110) will have higher conversion efficiencies, thereby rejecting less waste heat at a lower temperature and may require alternate approaches to transferring waste heat to the spacecraft. RTGs, with efficiencies of 6 to 7 percent, reject their waste heat at the relatively high heat rejection temperature of 200 C. This is an advantage when rejecting heat to space; however, transferring heat to the internal spacecraft components requires a large and heavy radiator heat exchanger. At the same time, sensitive spacecraft instruments must be shielded from the thermal radiation of the RTG. The SRG110, with an efficiency around 22 percent and 50 C nominal housing surface temperature, can readily transfer the available waste heat directly via heat pipes, thermal straps, or fluid loops. The lower temperatures associated with the SRG110 avoid the chances of overheating other scientific components, eliminating the need for thermal shields. This provides the spacecraft designers more flexibility when locating the generator for a specific mission. A common misconception with high-efficiency systems is that there is not enough waste heat for spacecraft thermal management. This paper will dispel this misconception and investigate the use of a high-efficiency SRG110 for spacecraft thermal management and outline potential methods of

  7. Analysis of a case of internal contamination with cobalt radioisotopes.

    Science.gov (United States)

    Vrba, T; Malatova, I; Jurochova, B

    2007-01-01

    Internal contamination by compounds of cobalt radioisotopes occurs time to time at nuclear power plants. Intakes and committed effective doses are estimated by biokinetic models described in ICRP publications. The paper deals with a case of internal contamination of a worker engaged in a maintenance task at NPP Dukovany. In this case significant discrepancy was observed between intakes based on various datasets (whole body counting, analysis of urine and faeces) when default model setting was used. The reason of this phenomenon was searched for. Three different least square methods of fits were used to find out possible effect of a fitting method. The measured data were fitted by set of biokinetic functions, which covered all intake ways (ingestion and inhalation) and types (M, S, different AMADs and different f1) of the contaminant. The biokinetic model of cobalt needs further improvements as to find better agreement between data fit from direct measurements and bioassay.

  8. Development of stable isotope separation technology for radioisotope production

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Do Young; Kim, Cheol Jung; Park, Kyung Bae [and others

    2003-05-01

    The ultimate goal of this project is to construct the domestic production system of stable isotopes O-18 and Tl-203 used as target materials in accelerator for the production of medical radioisotopes F-18 and Tl-201, respectively. In order to achieve this goal, diode laser spectroscopic analytical system was constructed and automatic measurement computer software for the direct analysis of H{sub 2}{sup 16}O/H{sub 2}{sup 18}O ratio were developed. Distillation process, laser process, and membrane diffusion process were analyzed for the evaluation of O-18 production. And electromagnetic process, plasma process, and laser process were analyzed for the evaluation of Tl-203 production. UV laser system, IR laser system, and detailed system Tl-203 production were designed. Finally, current and future worldwide demand/supply of stable isotopes O-18 and Tl-203 were estimated.

  9. CALIBRATION OF DENSITOMETRY IN RADIO-ISOTOPIC IN SITU HYBRIDIZATION

    Directory of Open Access Journals (Sweden)

    Jan M Ruijter

    2011-05-01

    Full Text Available Densitometry on autoradiographs of sections processed for in situ hybridization provides a direct measure for the in situ quantification of mRNA. Gelatin spots, containing different concentrations of the radioisotope, and processed in parallel with the tissue sections, can be used as a sensitive model to calibrate the densitometric measurements. The shape of the gelatin spots was shown to be circular with a parabolic crosssectional profile. This simple shape allows the subdivision of the spot into a series of concentric rings, which enables an unbiased measurement of the optical density - radioactivity relation. This spot measurement is also applicable to DNA arrays spotted on glass or membranes. A new model, explaining the optical density of autoradiographs, was derived and fitted to the calibration points. The use of this calibration method is crucial for the correct interpretation of autoradiographs

  10. Studies of radioisotope production with an AVF cyclotron in TIARA

    Energy Technology Data Exchange (ETDEWEB)

    Sekine, Toshiaki [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    The production of radioisotopes to be used mainly for nuclear medicine and biology is studied with an AVF cyclotron in TIARA. A production method of no-carrier-added {sup 186}Re with the {sup 186}W(p,n){sup 186}Re reaction has been developed; this product may be used as a therapeutic agent in radioimmunotherapy due to the adequate nuclear and chemical properties. For the study of the function of plants using a positron-emitter two-dimensional imaging system, a simple method of producing the positron emitter {sup 18}F in water was developed by taking advantage of a highly-energetic {alpha} beam from the AVF cyclotron. (author)

  11. Use of radioisotope scan in evaluation of intrascrotal lesions

    Energy Technology Data Exchange (ETDEWEB)

    Riley, T.W.; Mosbaugh, P.G.; Coles, J.L.; Newman, D.M.; Van Hove, E.D.; Heck, L.L.

    1976-10-01

    There were 98 patients with a variety of intrascrotal lesions studied with a radioisotope 99mtechnetium-pertechnetate scanning technique. Retrospective analysis in 50 patients subjected to an operation revealed a 94 percent accuracy of the scan in the differential diagnosis of testicular torsion and epididymitis as compared to a clinical accuracy of 48 percent. In 7 patients with a scan diagnosis of epididymo-orchitis with abscess the diagnosis was confirmed during the operation or by followup examination. While the scan has been a simple, safe, rapid and reliable technique to differentiate acute and subacute lesions, it has proved to be of limited diagnostic significance in cases of chronic intrascrotal lesions and carcinoma.

  12. Current status of radioisotope production in the year of 2003

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seon Duk; Bang, H. S.; Shin, B. C

    2004-02-01

    The RIPF(Radio Isotope Production Facility) is the unique facility in Korea which has been used for the isotope production. Through the survey on the radioisotope quantities of production and consumption in the domestic industry, we were trying to show the trend of isotope production. The quantities of Tc-99m, Mo-99, Cr-51, I-131 solution and I-131 capsule produced in the hot cell and clean room of RIPF were compared with the quantities at the previous year. Also the output of the labeling compound such as Hippuran, MIBG, RIHSA, Phytate, MDP, DISIDA, DTPA, etc was compared with the previous year by the radioactivity and the vial. We treated the sum of selling amount of industrial isotopes and tracer isotopes and the status of technical supports also.

  13. Fabrication of light weight radioisotope heater unit hardware components

    Science.gov (United States)

    McNeil, Dennis C.

    1996-03-01

    The Light Weight Radioisotope Heater Unit (LWRHU) is planned to be used on the National Aeronautics and Space Administration (NASA) Cassini Mission, to provide localized thermal energy as strategic locations on the spacecraft. These one watt heater units will support the operation of many on-board instruments that require a specific temperature range to function properly. The system incorporates a fuel pellet encapsulated in a vented metallic clad fabricated from platinum-30% rhodium (Pt-30%Rh) tubing, sheet and foil materials. To complete the package, the clad assemblies are placed inside a combination of graphite components. This report describes the techniques employed by Mound related to the fabrication and sub assembly processes of the LWRHU clad hardware components. Included are details concerning configuration control systems, material procurement and certification, hardware fabrication specifics, and special processes that are utilized.

  14. Differentiation of Pigment in Eggs Using Carbon ((13)C/(12)C) and Nitrogen ((15)N/(14)N) Stable Isotopes.

    Science.gov (United States)

    Sun, Feng M; Shi, Guang Y; Wang, Hui W

    2016-07-01

    Consumers prefer natural and healthy food, but artificial pigments are often abused in egg products. The study aimed at differentiating the origin of pigments in eggs by applying the technique of carbon ((13)C/(12)C) and nitrogen ((15)N/(14)N) stable isotope analysis. Five hundred sixty laying hens were randomly distributed into 14 treatments, which were divided into four groups: maize, carophyll red pigment, carophyll yellow pigment, and a mixture of carophyll red and yellow pigments. Eggs were collected and pretreated to determe the values of the Roche Yolk Color Fan (RCF), δ(13)C, and δ(15)N. With increasing maize content, the RCF and δ(13)C values of yolks increased. Moreover, the RCF values in the three pigment groups were significantly influenced by the artificial colors, but δ(13)C values were not significantly different, regardless of the existence of pigment. The δ(15)N values in all treatments did not vary as regularly as the carbon stable isotope. A strong positive correlation was found between RCF and δ(13)C in the maize group, but no such correlation was be observed in the pigment groups. It is concluded that carbon stable isotope ratio analysis (δ(13)C) of the yolk can be used to differentiate the origin of the pigment added to eggs.

  15. Assay for vitamin B12 absorption and method of making labeled vitamin B12

    Science.gov (United States)

    Anderson, Peter J [Davis, CA; Dueker, Stephen [Davis, CA; Miller, Joshua [Davis, CA; Green, Ralph [Elmacero, CA; Roth, John [Davis, CA; Carkeet, Colleen [Silver Spring, MD; Buchholz,; Bruce, A [Orinda, CA

    2012-06-19

    The invention provides methods for labeling vitamin B12 with .sup.14C, .sup.13C, tritium, and deuterium. When radioisotopes are used, the invention provides for methods of labeling B12 with high specific activity. The invention also provides labeled vitamin B12 compositions made in accordance with the invention.

  16. Advanced Stirling Convertor Development for NASA Radioisotope Power Systems

    Science.gov (United States)

    Wong, Wayne A.; Wilson, Scott D.; Collins, Josh

    2015-01-01

    Sunpower Inc.'s Advanced Stirling Convertor (ASC) initiated development under contract to the NASA Glenn Research Center and after a series of successful demonstrations, the ASC began transitioning from a technology development project to a flight development project. The ASC has very high power conversion efficiency making it attractive for future Radioisotope Power Systems (RPS) in order to make best use of the low plutonium-238 fuel inventory in the United States. In recent years, the ASC became part of the NASA and Department of Energy (DOE) Advanced Stirling Radioisotope Generator (ASRG) Integrated Project. Sunpower held two parallel contracts to produce ASCs, one with the DOE and Lockheed Martin to produce the ASC-F flight convertors, and one with NASA Glenn for the production of ASC-E3 engineering units, the initial units of which served as production pathfinders. The integrated ASC technical team successfully overcame various technical challenges that led to the completion and delivery of the first two pairs of flightlike ASC-E3 by 2013. However, in late fall 2013, the DOE initiated termination of the Lockheed Martin ASRG flight development contract driven primarily by budget constraints. NASA continues to recognize the importance of high-efficiency ASC power conversion for RPS and continues investment in the technology including the continuation of ASC-E3 production at Sunpower and the assembly of the ASRG Engineering Unit #2. This paper provides a summary of ASC technical accomplishments, overview of tests at Glenn, plans for continued ASC production at Sunpower, and status of Stirling technology development.

  17. Pathway of radioisotopes from land surface to sewage sludge

    Science.gov (United States)

    Fischer, Helmut W.; Yokoo, Yoshiyuki

    2014-05-01

    Radioactive surface contaminations will only partially remain at the original location - a fraction of the inventory will take part in (mainly terrestrial and aquatic) environmental transport processes. The probably best known and most important process comprises the food chain. Besides, the translocation of dissolved and particle-bound radioisotopes with surface waters plays an important role. These processes can have the effect of displacing large radioisotope amounts over considerable distances and of creating new sinks and hot spots, as it is already known for sewage sludge. We are reporting on a combined modeling and experimental project concerning the transport of I-131 and Cs-134/Cs-137 FDNPP 2011 depositions in the Fukushima Prefecture. Well-documented experimental data sets are available for surface deposition and sewage sludge concentrations. The goal is to model the pathway in between, involving surface runoff, transport in the sewer system and processes in the sewage treatment plant. Watershed runoff and sewer transport will be treated with models developed recently by us in other projects. For sewage treatment processes a new model is currently being constructed. For comparison and further validation, historical data from Chernobyl depositions and tracer data from natural and artificial, e.g. medical, isotopes will be used. First results for 2011 data from Fukushima Prefecture will be presented. The benefits of the study are expected to be two-fold: on one hand, the abundant recent and historical data will help to develop and improve environmental transport models; on the other hand, both data and models will help in identifying the most critical points in the envisaged transport pathways in terms of radiation protection and waste management.

  18. Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    Science.gov (United States)

    Anderson, William G.; Tarau, Calin

    2008-01-01

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling convertor provides this cooling. If the Stirling engine stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) was designed to allow multiple stops and restarts of the Stirling engine. A VCHP was designed for the Advanced Stirling Radioisotope Generator, with a 850 °C heater head temperature. The VCHP turns on with a ΔT of 30 °C, which is high enough to not risk standard ASRG operation but low enough to save most heater head life. This VCHP has a low mass, and low thermal losses for normal operation. In addition to the design, a proof-of-concept NaK VCHP was fabricated and tested. While NaK is normally not used in heat pipes, it has an advantage in that it is liquid at the reservoir operating temperature, while Na or K alone would freeze. The VCHP had two condensers, one simulating the heater head, and the other simulating the radiator. The experiments successfully demonstrated operation with the simulated heater head condenser off and on, while allowing the reservoir temperature to vary over 40 to 120 °C, the maximum range expected. In agreement with previous NaK heat pipe tests, the evaporator ΔT was roughly 70 °C, due to distillation of the NaK in the evaporator.

  19. A reanalysis of radioisotope measurements of the $^9$Be$(\\gamma,n)^8$Be cross-section

    CERN Document Server

    Robinson, Alan E

    2016-01-01

    The $^9$Be$(\\gamma,n)^8$Be reaction is enhanced by a near threshold $1/2^+$ state. Contradictions between existing measurements of this reaction cross-section affect calculations of astrophysical r-process yields, dark matter detector calibrations, and the theory of the nuclear structure of $^9$Be. Select well-documented radioisotope $^9$Be$(\\gamma,n)$ source yield measurements have been reanalyzed, providing a set of high-accuracy independently measured cross sections. A Breit-Wigner fit of these corrected measurements yields $E_R=1738.8^{+5.0}_{-4.2}$~keV, $\\Gamma_\\gamma=0.771^{+0.055}_{-0.044}$~eV, and $\\Gamma_n=268^{+40}_{-33}$~keV for the $1/2^+$ state. The fit favors a resonant $1/2^+$ state, but a virtual state is not excluded.

  20. Studies of One-Nucleon Transfer Reactions on Boron -11 and CARBON-12.

    Science.gov (United States)

    Foot, Penelope Bernadette

    This thesis describes a study of the ^{11}B(d,n)^{12 }C and ^{12}C(t, alpha)^{11} B reactions. The Indiana University Cyclotron Facility produced the 79 MeV deuterons for the ^{11} B(d,n)^{12}C experiment. Time of flight measurements were performed to obtain neutron energy spectra. The energy resolution was typically 300 keV (~{1over 2} nsec). Cross sections were extracted for five well-resolved bound states in ^{12}C at 0.00, 4.44, 9.64, 12.71 and 15.11 MeV. The experimental cross sections were compared with the results of theoretical predictions. The effect of including, in these calculations, the breakup of the deuteron into low energy relative S states during the course of the reaction was investigated. Spectroscopic factors were then determined for the above five states in ^{12}C and compared with theoretical values. A subsequent experiment was performed at the same energy with vector polarized deuterons in order to study the effects of deuteron breakup on the corresponding analysing powers. This was the first time that analysing powers had been measured for this reaction. The effects on the cross section and analysing power calculations of exact finite range and the D state of the deuteron were investigated using the Reid soft-core potential for the proton-neutron interaction. The possible role of a two step process in the population of the 2 ^{+} state at 4.44 MeV in ^{12}C was examined. The effects on the analysing power for this state, of contributions from the 2p-1f shell in the 4.44 MeV wavefunction, were also discussed. Differential cross sections for the ^ {12}C(t,alpha) ^{11}B reaction, using 33 MeV tritons from the Daresbury Nuclear Structure Facility, were extracted for transitions to the 0.00, 2.125, 4.445, 5.021, 6.743, 7.286, 7.978 and 8.559 MeV states in ^{11 }B. The results of CRC calculations were compared with DWBA and CCBA calculation for the single step and two step transitions respectively. The spin of the 8.559 MeV state in ^{11}B, which

  1. Gas-Phase Synthesis of Dimethyl Carbonate from Methanol and Carbon Dioxide Over Co1.5PW12O40 Keggin-Type Heteropolyanion

    Directory of Open Access Journals (Sweden)

    Ahmed Aouissi

    2010-03-01

    Full Text Available The reactivity of Co1.5PW12O40 in the direct synthesis of dimethyl carbonate (DMC from CO2 and CH3OH was investigated. The synthesized catalyst has been characterized by means of FTIR, XRD, TG, and DTA and tested in gas phase under atmospheric pressure. The effects of the reaction temperature, time on stream, and methanol weight hourly space velocity (MWHSV on the conversion and DMC selectivity were investigated. The highest conversion (7.6% and highest DMC selectivity (86.5% were obtained at the lowest temperature used (200 °C. Increasing the space velocity MWHSV increased the selectivity of DMC, but decreased the conversion. A gain of 18.4% of DMC selectivity was obtained when the MWHSV was increased from 0.65 h-1 to 3.2 h-1.

  2. Microstructural morphology of the semi-solid high carbon steel T12 before and after rheo-rolling

    Institute of Scientific and Technical Information of China (English)

    Jiguang Li; Yonglin Kang; Aimin Zhao; Yi Sun; Man Cheng

    2005-01-01

    The semi-solid high carbon steel T12 was rolled in a closed box groove under a certain condition by the rheo-rolling equipment, and the microstructural morphology of the semi-solid T12 before and after deformation was investigated by optical microscope to analyze and summarize the microstructure evolution law of T12 deformed in semi-solid state. The experiment results show that the grain shape before deformation of the semi-solid T12 steel displays globule or ellipse by the electromagnetic stirring,the distribution of solid and liquid phases is homogeneous. But the microstructure of semi-solid product after rheo-rolling exhibits macrosegregation that the distribution of liquid and solid phases changes, the liquid phases divorce from the solid phases. In the transverse section, most of the solid phases get together in the center of the specimen, the liquid phases flow to the surface or the edge of the specimen, and the grains occur plastic deformation while reduction increased. In longitudinal section, the middle microstructure of the specimen is more homogeneous than that at the head or tail, the head microstructure is similar to the tail and the size of the grains is not homogeneous.

  3. Radioisotope electric propulsion of sciencecraft to the outer solar system and near-interstellar space

    Energy Technology Data Exchange (ETDEWEB)

    Noble, R.J.

    1998-08-01

    Recent results are presented in the study of radioisotope electric propulsion as a near-term technology for sending small robotic sciencecraft to the outer Solar System and near-interstellar space. Radioisotope electric propulsion (REP) systems are low-thrust, ion propulsion units based on radioisotope electric generators and ion thrusters. Powerplant specific masses are expected to be in the range of 100 to 200 kg/kW of thrust power. Planetary rendezvous missions to Pluto, fast missions to the heliopause (100 AU) with the capability to decelerate an orbiter for an extended science program and prestellar missions to the first gravitational lens focus of the Sun (550 AU) are investigated.

  4. Characterization of front-end electronics for CZT based handheld radioisotope identifier

    Science.gov (United States)

    Lombigit, L.; Rahman, Nur Aira Abd; Mohamad, Glam Hadzir Patai; Ibrahim, Maslina Mohd; Yussup, Nolida; Yazid, Khairiah; Jaafar, Zainudin

    2016-01-01

    A radioisotope identifier device based on large volume Co-planar grid CZT detector is current under development at Malaysian Nuclear Agency. This device is planned to be used for in-situ identification of radioisotopes based on their unique energies. This work reports on electronics testing performed on the front-end electronics (FEE) analog section comprising charge sensitive preamplifier-pulse shaping amplifier chain. This test involves measurement of charge sensitivity, pulse parameters and electronics noise. This report also present some preliminary results on the spectral measurement obtained from gamma emitting radioisotopes.

  5. Characterization of front-end electronics for CZT based handheld radioisotope identifier

    Energy Technology Data Exchange (ETDEWEB)

    Lombigit, L., E-mail: lojius@nm.gov.my [Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia); Rahman, Nur Aira Abd; Mohamad, Glam Hadzir Patai; Ibrahim, Maslina Mohd; Yussup, Nolida; Yazid, Khairiah; Jaafar, Zainudin

    2016-01-22

    A radioisotope identifier device based on large volume Co-planar grid CZT detector is current under development at Malaysian Nuclear Agency. This device is planned to be used for in-situ identification of radioisotopes based on their unique energies. This work reports on electronics testing performed on the front-end electronics (FEE) analog section comprising charge sensitive preamplifier-pulse shaping amplifier chain. This test involves measurement of charge sensitivity, pulse parameters and electronics noise. This report also present some preliminary results on the spectral measurement obtained from gamma emitting radioisotopes.

  6. Assessment of the radiological control at the IPEN radioisotope production facility

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, J.C.G.G.; Sanches, M.P.; Rodrigues, D.L.; Campos, D.; Nogueira, P.R.; Damatto, S.R.; Pecequilo, B.R.S. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    The main objective of this work is to evaluate the 2013 annual radiological control results in the radiopharmaceuticals areas of the Nuclear and Energy Research Institute, IPEN/SP, Brazil and the environmental radiological impact, resulting from the practices there performed. The current evaluation was performed through the analysis of the results obtained from occupational and environmental monitoring with air samplers and TL dosimeters. All monitoring results were compared with the limits established by national standards. The radionuclides detected by air sampling (in activated carbon cartridges and filter paper) at the workplace during radioisotope production were {sup 131}I, {sup 99m}Tc and {sup 99}Mo, with activities concentrations values below the annual limits values. For the radioactive gaseous releases (Bq/m{sup 3} ), the activities concentrations also remained below the maximum admissible values, excepting to {sup 125}I release due to an unusual event occurred in a researcher laboratory, but the radiological impact to environmental was no significant. The occupational monitoring assessment was confirmed by the Environmental Radiological Monitoring Program results with air samplers and TL dosimeters. The mean annual background radiation at IPEN in 2013, according to the Environmental Radiological Monitoring Program results was 1.06 mSv. y{sup -1} , below the ICRP 103 recommended limit of 20 mSv.y{sup -1} for workers. (author)

  7. Performance analysis of coated 238PuO2 fuel particles compact for radioisotope heater units

    Science.gov (United States)

    Tournier, Jean-Michel; El-Genk, Mohamed S.

    2000-01-01

    A fuel form consisting of coated plutonia fuel particles dispersed in a graphite matrix is being investigated for use in Radioisotope Heater Units (RHUs). The fuel particles consist of a 238PuO2 kernel (300-1200 μm in diameter), a 5-μm PyC inner coating and a ZrC outer coating (>=10 μm). The latter, an extremely strong material at high temperatures, serves as a pressure vessel for maintaining the integrity of the fuel particle and containing the helium generated by radioactive decay. Parametric analyses compared the thermal powers of the coated particle fuel compact (CPFC) RHU and LWRHU. Both utilize Fine-Weave Pierced Fabric (FWPF) aeroshell and PyC insulation sleeves. During normal operation, the fuel temperature is ~800 K, but could reach as much as 1723 K during an accidental re-entry heating. Assuming full helium release, a single-size particle (500 μm) fuel compact would maintain its integrity at a temperature of 1723 K, after 10 years storage time before launch. When replacing the LWRHU fuel pellet, Pt-alloy clad and inner PyC insulation sleeve with CPFC, the calculated thermal power of the CPFC-RHU is 1.5, 2.3 and 2.4 times that of LWRHU, for 100%, 10%, and 5% helium release, respectively, with little change in total mass. A fuel compact using binary-size particles (300 and 1200 μm diameters) would deliver 15% more thermal power. A one-dimensional, transient thermal analysis of the CPFC-RHU showed that during accidental re-entry the maximum fuel temperature in the CPFC would be 1734 K. .

  8. The electron mass from $g$-factor measurements on hydrogen-like carbon $^{12}$C$^{5+}$

    CERN Document Server

    Köhler, Florian; Kracke, Anke; Werth, Günter; Quint, Wolfgang; Blaum, Klaus

    2016-01-01

    The electron mass in atomic mass units has been determined with a relative uncertainty of $2.8\\cdot 10^{-11}$, which represents a 13-fold improvement of the 2010 CODATA value. The underlying measurement principle combines a high-precision measurement of the Larmor-to-cyclotron frequency ratio on a single hydrogen-like carbon ion in a Penning trap with a corresponding very accurate $g$-factor calculation. Here, we present the measurement results in detail, including a comprehensive discussion of the systematic shifts and their uncertainties. A special focus is set on the various sources of phase jitters, which are essential for the understanding of the applied line-shape model for the $g$-factor resonance.

  9. Nonthermal inactivation of Escherichia coli K12 in buffered peptone water using a pilot-plant scale supercritical carbon dioxide system with gas-liquid porous metal contractor

    Science.gov (United States)

    This study evaluated the effectiveness of a supercritical carbon dioxide (SCCO2) system, with a gas-liquid CO2 contactor, for reducing Escherichia coli K12 in diluted buffered peptone water. 0.1% (w/v) buffered peptone water inoculated with E. coli K12 was processed using the SCCO2 system at CO2 con...

  10. Cascaded Thermoelectric Conversion-Advanced Radioisotope Power Systems (CTC-ARPSs)

    Science.gov (United States)

    El-Genk, Mohamed S.; Saber, Hamed H.

    2004-02-01

    Conceptual designs of Advanced Radioisotope Power System (ARPS) with Cascaded Thermoelectric Converters (CTCs) are developed and optimized for maximum efficiency operation for End-Of Mission (EOM) electrical power of at least 100 We. These power systems each employs four General Purpose Heat Source (GPHS) bricks generating 1000 Wth at Beginning-of-Life (BOL) and 32 Cascaded Thermoelectric Modules (CTMs). Each CTM consists of a top and a bottom array of thermoelectric unicouples, which are thermally, but not electrically, coupled. The top and bottom arrays of the CTMs are connected electrically in series in two parallel strings with the same nominal voltage of > 28 VDC. The SiGe unicouples in the top array of the CTMs are optimized for nominal hot shoe temperature of 1273 K and constant cold shoe temperature of either 780 K or 980 K, depending on the thermoelectric materials of the unicouples in the bottom array. For a SiGe cold junction temperature of 780 K, the unicouples in the bottom array have p-legs of TAGS-85 and n-legs of 2N-PbTe and operate at constant hot junction temperature of 765 K and nominal cold junction temperature of 476.4 K. When the SiGe cold junction temperature is 980 K, the unicouples in the bottom arrays of CTMs have p-legs of CeFe3.5Co0.5Sb12 or CeFe3.5Co0.5Sb12 and Zn4Sb3, segments and n-legs of CoSb3 and operate at constant hot junction temperature of 965 K and nominal cold junction temperatures of 446.5 K or 493.5 K, respectively. The CTC-ARPSs have a nominal efficiency of 10.82% - 10.85% and generate BOL power of 108 We. This system efficiency is ~ 80% higher than that of State-of-the-Art (SOA) Radioisotope Thermoelectric Generators (RTGs), requiring 7 GHPS bricks and generating 105 We at BOL. The CTC-ARPSs have specific powers of 8.2 We/kg to 8.8 We/kg, which are 71% to 83% higher, respectively, than that of the SOA-RTGs, and use ~ 43% less 238PuO2 fuel.

  11. Sublimation behavior of silicon nitride /Si3N4/ coated silicon germanium /SiGe/ unicouples. [for Radioisotope Thermoelectric Generators

    Science.gov (United States)

    Stapfer, G.; Truscello, V. C.

    1975-01-01

    For the Multi-Hundred Watt (MHW) Radioisotope Thermoelectric Generator (RTG), the silicon germanium unicouples are coated with silicon nitride to minimize degradation mechanisms which are directly attributable to material sublimation effects. A program is under way to determine the effective vapor suppression of this coating as a function of temperature and gas environment. The results of weight loss experiments, using Si3N4 coated hot shoes (SiMo), operating over a temperature range from 900 C to 1200 C, are analyzed and discussed. These experiments were conducted both in high vacuum and at different pressures of carbon monoxide (CO) to determine its effect on the coating. Although the results show a favorable vapor suppression at all operating temperatures, the pressure of the CO and the thickness of the coating have a decided effect on the useful lifetime of the coating.

  12. Experimental investigation on melt coolability under bottom flooding with and without decay heat simulation

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Nitendra [Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094, Maharashtra (India); Kulkarni, Parimal P. [Reactor Engineering Division, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra (India); Nayak, Arun K., E-mail: arunths@barc.gov.in [Reactor Engineering Division, Bhabha Atomic Research Centre, Mumbai 400085, Maharashtra (India)

    2015-04-15

    Highlights: • The effect of decay heat on melt coolability under bottom flooding was studied. • Decay heat of 0.5 MW/m{sup 3} was simulated. • A single simulant material with same mass and initial temperature was used. • Quenching of melt pool does not depend on decay heat. • Comparison of with and without decay heat experiments has been presented. - Abstract: Investigations on severe accident phenomena help us in understanding the realistic accidental phenomena for the assessment of associated risk. The societal impact of radiological leakage to the environment has demanded further robustness in the line of defence of nuclear safety. Thus, to ensure the cooling and stabilization of corium within reactor containment in case of severe accident scenarios, many new reactors have been envisaged with core catcher. In this regard, corium coolability still remains an unresolved issue in spite of several efforts being taken towards its understanding. After studying the various cooling strategies, it has been demonstrated that melt coolability using bottom flooding of water is one of the most efficient techniques so far. To study the effect of decay heat on melt pool coolability under bottom flooding condition, two experiments have been performed in this paper; one without the decay heat and the other with decay heat. The test section used for carrying out these experiments consisted of two parts viz. lower part for retaining the melt from furnace, water inlet and melt quenching, and upper part for steam expansion and its outlet. The total height of the test section was 1400 mm and was made of 33 mm thick carbon steel. Total six stainless steel nozzles of diameter 12 mm were used for injecting water at the bottom of the melt pool. The lower part was surrounded by 10 radiative heaters to simulate decay heat of 10 kW which corresponds to 0.5 MW/m{sup 3}. The experiments showed that quenching of about 25 l of melt at initial temperature of nearly 1200 °C took only a

  13. Long Life 600W Hall Thruster System for Radioisotope Electric Propulsion Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Radioisotope Electric Propulsion (REP) offers the prospect for a variety of new science missions by enabling use of Hall Effect propulsion in the outer solar system,...

  14. Radioisotope Electric Propulsion (REP): A Near-Term Approach to Nuclear Propulsion

    Science.gov (United States)

    Schmidt, George R.; Manzella, David H.; Kamhawi, Hani; Kremic, Tibor; Oleson, Steven R.; Dankanich, John W.; Dudzinski, Leonard A.

    2009-01-01

    Studies over the last decade have shown radioisotope-based nuclear electric propulsion to be enhancing and, in some cases, enabling for many potential robotic science missions. Also known as radioisotope electric propulsion (REP), the technology offers the performance advantages of traditional reactor-powered electric propulsion (i.e., high specific impulse propulsion at large distances from the Sun), but with much smaller, affordable spacecraft. Future use of REP requires development of radioisotope power sources with system specific powers well above that of current systems. The US Department of Energy and NASA have developed an advanced Stirling radioisotope generator (ASRG) engineering unit, which was subjected to rigorous flight qualification-level tests in 2008, and began extended lifetime testing later that year. This advancement, along with recent work on small ion thrusters and life extension technology for Hall thrusters, could enable missions using REP sometime during the next decade.

  15. A study of isospin symmetry breaking in carbon 12 with 50 MeV pions

    Energy Technology Data Exchange (ETDEWEB)

    Applegate, J M

    1993-03-01

    In the first experiment to use the superconducting RF cavity at LAMPF known as the Scruncher, cross sections have been measured for the 1+ doublet in {sup 12}C by 50 MeV {pi}r{sup {plus_minus}} scattering. The cross section ratio of the isoscalar to the isovector states was found to be 6.8 {plus_minus} 1.3 for {pi}{sup +}+ scattering and 3.9 {plus_minus} 1.4 for {pi}{sup {minus}} scattering. These ratios give an isospin mixing matrix element H{sub 01}, of 119 {plus_minus} 40 key, in good agreement with the average value of 123 {plus_minus} 26 key deduced from previous pion-scattering data and with values deduced from other probes. The ratio of {pi}{sup +} + p to {pi}{sup {minus}} + p cross sections was determined experimentally to be 2.60 {plus_minus} 0.11, in agreement with a theoretical value of 2.85. The agreement of these results indicates that the impulse approximation is valid at 50 MeV. Cross sections were also measured for the elastic and collective states in {sup 12}C and were generally described well by distorted wave Born approximation calculations published previously.

  16. Operational readiness review plan for the radioisotope thermoelectric generator materials production tasks

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R.H.; Martin, M.M.; Riggs, C.R.; Beatty, R.L.; Ohriner, E.K.; Escher, R.N.

    1990-04-19

    In October 1989, a US shuttle lifted off from Cape Kennedy carrying the spacecraft Galileo on its mission to Jupiter. In November 1990, a second spacecraft, Ulysses, will be launched from Cape Kennedy with a mission to study the polar regions of the sun. The prime source of power for both spacecraft is a series of radioisotope thermoelectric generators (RTGs), which use plutonium oxide (plutonia) as a heat source. Several of the key components in this power system are required to ensure the safety of both the public and the environment and were manufactured at Oak Ridge National Laboratory (ORNL) in the 1980 to 1983 period. For these two missions, Martin Marietta Energy Systems, Inc. (Energy Systems), will provide an iridium-alloy component used to contain the plutonia heat source and a carbon-composite material that serves as a thermal insulator. ORNL alone will continue to fabricate the carbon-composite material. Because of the importance to DOE that Energy Systems deliver these high-quality components on time, performance of an Operational Readiness Review (ORR) of these manufacturing activities is necessary. Energy Systems Policy GP-24 entitled Operational Readiness Process'' describes the formal and comprehensive process by which appropriate Energy Systems activities are to be reviewed to ensure their readiness. This Energy System policy is aimed at reducing the risks associated with mission success and requires a management-approved readiness plan'' to be issued. This document is the readiness plan for the RTG materials production tasks. 6 refs., 11 figs., 1 tab.

  17. ARAS: an automated radioactivity aliquoting system for dispensing solutions containing positron-emitting radioisotopes

    OpenAIRE

    2016-01-01

    Background Automated protocols for measuring and dispensing solutions containing radioisotopes are essential not only for providing a safe environment for radiation workers but also to ensure accuracy of dispensed radioactivity and an efficient workflow. For this purpose, we have designed ARAS, an automated radioactivity aliquoting system for dispensing solutions containing positron-emitting radioisotopes with particular focus on fluorine-18 (18F). Methods The key to the system is the combina...

  18. Development of Kabila rocket: A radioisotope heated thermionic plasma rocket engine

    OpenAIRE

    2015-01-01

    A new type of plasma rocket engine, the Kabila rocket, using a radioisotope heated thermionic heating chamber instead of a conventional combustion chamber or catalyst bed is introduced and it achieves specific impulses similar to the ones of conventional solid and bipropellant rockets. Curium-244 is chosen as a radioisotope heat source and a thermal reductive layer is also used to obtain precise thermionic emissions. The self-sufficiency principle is applied by simultaneously heating up the e...

  19. SU-E-CAMPUS-I-03: Dosimetric Comparison of the Hypoxia Agent Iodoazomycin Arabinoside (IAZA) Labeled with the Radioisotopes I-123, I-131 and I-124

    Energy Technology Data Exchange (ETDEWEB)

    Jans, H-S [Cross Cancer Institute, Edmonton, AB (Canada); Dept. of Oncology, University of Alberta, Edmonton, AB (Canada); Stypinski, D [Celerion Inc., Lincoln, NE (United States); Mcquarrie, S; Kumar, P; Mercer, J; McEwan, S [Dept. of Oncology, University of Alberta, Edmonton, AB (Canada); Wiebe, L [Cross Cancer Institute, Edmonton, AB (Canada)

    2014-06-15

    Purpose: To compare the radiation dose to normal organs from the radio-iodinated, hypoxia-binding radiosensitizer iodoazomycin arabinoside (IAZA) for three different isotopes of iodine. Methods: Dosimety studies with normal volunteers had been carried out with [{sup 123}I]IAZA, a drug binding selectively to hypoxic sites. Two other isotopes of iodine, {sup 131}I and {sup 124}I, offer the opportunity to use IAZA as an agent for radioisotope therapy and as an imaging tracer for Positron Emission Tomography. Radioisotope dosimetry for {sup 131}I and {sup 124}I was performed by first deriving from the [{sup 123}I]IAZA studies biological uptake and excretion data. The cumulated activities for {sup 131}I or {sup 124}I where obtained by including their half-lives when integrating the biological data and then extrapolating to infinite time points considering a) physical decay only or b) physical and biological excretion. Doses were calculated using the Medical Internal Radiation Dose (MIRD) schema (OLINDA1.1 code, Vanderbilt 2007). Results: Compared to {sup 123}I, organ doses were elevated on average by a factor 6 and 9 for {sup 131}I and {sup 124}I, respectively, if both physical decay and biological excretion were modeled. If only physical decay is considered, doses increase by a factor 18 ({sup 131}I) and 19 ({sup 124}I). Highest organ doses were observed in intestinal walls, urinary bladder and thyroid. Effective doses increased by a factor 11 and 14 for {sup 131}I and {sup 124}I, respectively, if biological and physical decay are present. Purely physical decay yields a 23-fold increase over {sup 123}I for both, {sup 131}I and {sup 124}I. Conclusion: Owing to the significant dose increase, caused by their longer half life and the approximately 10 times larger electronic dose deposited in tissue per nuclear decay, normal tissue doses of IAZA labeled with {sup 131}I and {sup 124}I need to be carefully considered when designing imaging and therapy protocols for clinical

  20. Cryogenic optical measurements of 12-segment-bonded carbon-fiber-reinforced silicon carbide composite mirror with support mechanism

    Science.gov (United States)

    Kaneda, Hidehiro; Nakagawa, Takao; Onaka, Takashi; Enya, Keigo; Makiuti, Sin'itirou; Takaki, Junji; Haruna, Masaki; Kume, Masami; Ozaki, Tsuyoshi

    2008-03-01

    A 720 mm diameter 12-segment-bonded carbon-fiber-reinforced silicon carbide (C/SiC) composite mirror has been fabricated and tested at cryogenic temperatures. Interferometric measurements show significant cryogenic deformation of the C/SiC composite mirror, which is well reproduced by a model analysis with measured properties of the bonded segments. It is concluded that the deformation is due mostly to variation in coefficients of thermal expansion among segments. In parallel, a 4-degree-of-freedom ball-bearing support mechanism has been developed for cryogenic applications. The C/SiC composite mirror was mounted on an aluminum base plate with the support mechanism and tested again. Cryogenic deformation of the mirror attributed to thermal contraction of the aluminum base plate via the support mechanism is highly reduced by the support, confirming that the newly developed support mechanism is promising for its future application to large-aperture cooled space telescopes.

  1. Black carbon record of the wildfire history of western Sichuan Province in China over the last 12.8 ka

    Science.gov (United States)

    Sun, Weiwei; Zhang, Enlou; Shen, Ji; Chen, Rong; Liu, Enfeng

    2016-01-01

    Wildfire is recognized as a critical Earth system process which affects the global carbon cycle, atmospheric chemistry, and ecosystem dynamics. Estimating the potential impact of future climate change on the incidence of fire requires an understanding of the long-term interactions of fire, climate, vegetation, and human activity. Accordingly, we analyzed the black carbon content and the pollen stratigraphy of sediments spanning the past 12.8 ka from Lake Muge Co, an alpine lake in western Sichuan Province, in order to determine the main factors influencing regional fire regimes. The results demonstrate that wildfires occurred frequently and intensively during the late deglaciation and the early Holocene when the regional vegetation was dominated by deciduous forests. Wildfire occurrence decreased significantly during the Holocene climatic optimum between 9.2 and 5.6 cal ka BP. Overall, the wildfire history of western Sichuan Province is similar to that of the Chinese Loess Plateau and of East Asia as a whole, suggesting that regional-scale fires depended mainly on changes in the intensity of the Asian summer monsoon. In addition, the fire regime of western Sichuan Province may have been influenced by the establishment of human settlement and agriculture in western Sichuan Province and the southeastern Tibetan Plateau after about 5.5 cal ka BP, and by an intensification of cereal cultivation coupled with population expansion in southwestern China during the last two millennia.

  2. Measurement of W + gamma Production in the W to Muon Decay Channel in Proton - Anti-proton Collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Tanimoto, Naho

    2005-03-01

    The production cross section and the kinematic properties of the decay products of W{gamma} in the W {yields} {mu}{nu} decay channel from p{bar p} collisions at {radical}s = 1.96 TeV are presented. The measurement use the high p{sub T} muon data from the upgraded Collider Detector at Fermilab (CDF). The data were collected between March 2002 and September 2003. The total integrated luminosities are 192 pb{sup -1} with the muon detector which covers the pseudorapidity region of |{eta}| {le} 0.6 and 175 pb{sup -1} with the muon detector covering the region 0.6 {le} |{eta}| {le} 1.0. In the Standard Model the {mu}{nu}{gamma} final states occur due to W{gamma} {yields} {mu}{nu}{gamma} production and via muon Bremsstrahlung, W {yields} {mu}{nu} {yields} {mu}{nu}{gamma}. W bosons are selected in their muon decay mode. Additionally, photons with transverse energy above 7 GeV, pseudorapidity in the central region (|{eta}| < 1.1) and muon-photon angular separation {Delta}R({mu},{gamma}) > 0.7 are selected. The author observes a total of 128 W{gamma} candidates, whereas the Standard Model expectation is 142.4 {+-} 9.5 events. The W{gamma} production cross section is found to be {sigma}(p{bar p} {yields} {mu}{nu}{gamma}) = 16.3 {+-} 2.3(stat.) {+-} 1.8(syst.) {+-} 1.2(lum.) [pb]. The theoretical prediction for this cross section is {sigma}(p{bar p} {yields} l{nu}{gamma}) = 19.3 {+-} 1.4(th.) [pb]. The Standard Model predictions for several kinematic + variables are compared with data for E{sub T}{sup {gamma}} > 7 GeV and {Delta}R({mu},{gamma}) > 0.7. The measured cross section and the photon and W boson production kinematics are found to agree with the Standard Model predictions.

  3. Short-range correlations in carbon-12, oxygen-16, and neon-20: Intrinsic properties

    Science.gov (United States)

    Braley, R. C.; Ford, W. F.; Becker, R. L.; Patterson, M. R.

    1972-01-01

    The Brueckner-Hartree-Fock (BHF) method has been applied to nuclei whose intrinsic structure is nonspherical. Reaction matrix elements were calculated as functions of starting energy for the Hamada-Johnston interaction using the Pauli operator appropriate to O-16 and a shifted oscillator spectrum for virtual excited states. Binding energies, single particle energies, radii, and shape deformations of the intrinsic state, in ordinary as well as renormalized BHF, are discussed and compared with previous HF studies and with experiment when possible. Results are presented for C-12, 0-16 and Ne-20. It is found that the binding energies and radii are too small, but that separation energies are well reproduced when the renormalized theory is used.

  4. Personal reflections on the highlights and changes in radiation and radioisotope measurement applications

    Science.gov (United States)

    Gardner, Robin P.; Lee, Kyoung O.

    2015-11-01

    This paper describes the recent changes that the authors have perceived in the use of radiation and radioisotope measurement applications. The first change is that due to the increased use of Monte Carlo simulation which has occurred from a normal evolutionary process. This is due in large part to the increased accuracy that is being obtained by the use of detector response functions (DRFs) and the simultaneous increased computational efficiency that has become available with these DRFs, the availability of a greatly improved weight windows variance reduction method, and the availability of inexpensive computer clusters. This first change is a happy one. The other change that is occurring is in response to recent terrorist activities. That change is the replacement or major change in the use of long-lived radioisotopes in radioisotope measurement and other radioisotope source applications. In general this can be done by improving the security of these radioisotope sources or by replacing them altogether by using machine sources of radiation. In either case one would like to preclude altogether or at least minimize the possibility of terrorists being able to obtain radioisotopes and use them for clandestine purposes.

  5. Radioisotope tracer study in a sludge hygienization research irradiator (SHRI).

    Science.gov (United States)

    Pant, H J; Thýn, J; Zitný, R; Bhatt, B C

    2001-01-01

    A radioisotope tracer study has been carried out in a batch type sludge hygienization research irradiator with flow from top to bottom, the objective being to measure flow rate, circulation and mixing times and to investigate the hydrodynamic behaviour of the irradiator for identifying the cause(s) of malfunction. A stimulus-response technique with NH4(82)Br as a tracer was used to measure the above parameters. Experiments were carried out at three different flow rates, i.e 1.0, 0.64 and 0.33 m3/min. Three combined models based on a set of differential equations are proposed and used to simulate the measured tracer concentration curves. The obtained parameters were used to estimate dead volume and analyse hydrodynamic behaviour of the irradiator. The nonlinear regression problem of model parameter estimation was solved using the Marquardt-Levenberg method. The measured flow rate was found to be in good agreement with the values shown by the flow meter. The circulation times were found to be half of the mixing times. A simple approach for estimation of dose based on a known vertical dose-rate profile inside the irradiator is presented. About one-fourth of the volume of the irradiator was found to be dead at lower flow rates and this decreased with increase in flow rate. At higher flow rates, a semi stagnant volume was found with slow exchange of flow between the active and dead volumes.

  6. Radioisotope tracer study in a sludge hygienization research irradiator (SHRI)

    Energy Technology Data Exchange (ETDEWEB)

    Pant, H.J. E-mail: hjpant@aspsara.barc.ernet.in; Thyn, J.; Zitny, R.; Bhatt, B.C

    2001-01-15

    A radioisotope tracer study has been carried out in a batch type sludge hygienization research irradiator with flow from top to bottom, the objective being to measure flow rate, circulation and mixing times and to investigate the hydrodynamic behaviour of the irradiator for identifying the cause(s) of malfunction. A stimulus-response technique with NH{sup 82}{sub 4}Br as a tracer was used to measure the above parameters. Experiments were carried out at three different flow rates, i.e 1.0, 0.64 and 0.33 m{sup 3}/min. Three combined models based on a set of differential equations are proposed and used to simulate the measured tracer concentration curves. The obtained parameters were used to estimate dead volume and analyse hydrodynamic behaviour of the irradiator. The nonlinear regression problem of model parameter estimation was solved using the Marquardt-Levenberg method. The measured flow rate was found to be in good agreement with the values shown by the flow meter. The circulation times were found to be half of the mixing times. A simple approach for estimation of dose based on a known vertical dose-rate profile inside the irradiator is presented. About one-fourth of the volume of the irradiator was found to be dead at lower flow rates and this decreased with increase in flow rate. At higher flow rates, a semi stagnant volume was found with slow exchange of flow between the active and dead volumes.

  7. Radioisotope Power Systems Reference Book for Mission Designers and Planners

    Science.gov (United States)

    Lee, Young; Bairstow, Brian

    2015-01-01

    The RPS Program's Program Planning and Assessment (PPA) Office commissioned the Mission Analysis team to develop the Radioisotope Power Systems (RPS) Reference Book for Mission Planners and Designers to define a baseline of RPS technology capabilities with specific emphasis on performance parameters and technology readiness. The main objective of this book is to provide RPS technology information that could be utilized by future mission concept studies and concurrent engineering practices. A progress summary from the major branches of RPS technology research provides mission analysis teams with a vital tool for assessing the RPS trade space, and provides concurrent engineering centers with a consistent set of guidelines for RPS performance characteristics. This book will be iterated when substantial new information becomes available to ensure continued relevance, serving as one of the cornerstone products of the RPS PPA Office. This book updates the original 2011 internal document, using data from the relevant publicly released RPS technology references and consultations with RPS technologists. Each performance parameter and RPS product subsection has been reviewed and cleared by at least one subject matter representative. A virtual workshop was held to reach consensus on the scope and contents of the book, and the definitions and assumptions that should be used. The subject matter experts then reviewed and updated the appropriate sections of the book. The RPS Mission Analysis Team then performed further updates and crosschecked the book for consistency. Finally, a second virtual workshop was held to ensure all subject matter experts and stakeholders concurred on the contents.

  8. Radioisotope studies of mucociliary system function in otorhinolaryngology

    Energy Technology Data Exchange (ETDEWEB)

    De Rossi, G. [Istituto di Medicina Nucleare, Rome (Italy)

    1992-12-31

    An `excursus` on the Nuclear Medicine methods at present available for the study of mucociliary system function in otorhinolaryngology is reported. To this end, ostoscintigraphy and rhinosctinigraphy prove to be exquisitely sensitive techniques. Otoscintigraphy is useful for pre-operative studies in the patients who are planned to undergo tympanoplasty for dry tympanic perforations. Rhinoscintigraphy is regarded as the most affordable and sound method to evaluate mucociliary system function in rhinopathies. It is also suggested for the pre- and post-operative assessment of polypectomy. Hence, otorhinolaryngology radioisotope methods deserve to be extensively dealt with in Nuclear Medicine treatises. (orig.) [Deutsch] Der Autor gibt einen Ueberblick ueber nuklear-medizinische Verfahren, die heutzutage fuer funktionelle Untersuchungen des mukoziliaren Systems in der HNO-Heilkunde zur Verfuegung stehen. Die Otoszintigraphie sowie die Rhinoszintigraphie erweisen sich in diesem Zusammenhang als Methoden mit einer ueberaus hohen Empfindlichkeit. Bei Patienten, die wegen einer Trommelfellperforation zur Trommelfellplastik vorgesehen sind, bewaehrt sich die Otoszintigraphie fuer praeoperative Untersuchungen. Die Rhinoszintigraphie wird bei den unterschiedlichsten Nasenerkrankungen als die rationellste und wirksamste Methode zur funktionellen Beurteilung des mukoziliaren Systems angesehen. Darueber hinaus wird sie fuer die praeoperative und postoperative Untersuchung bei Polypenexstirpationen empfohlen. Deshalb sollte den Methoden der Radioisotopenuntersuchungen in der HNO-Heilkunde ein hoeherer Stellenwert eingeraeumt werden. (orig.)

  9. Thermal vacuum life test facility for radioisotope thermoelectric generators

    Energy Technology Data Exchange (ETDEWEB)

    Deaton, R.L.; Goebel, C.J.; Amos, W.R.

    1990-01-01

    In the late 1970's, the Department of Energy (DOE) assigned Monsanto Research Corporation, Mound Facility, now operated by EG G Mound Applied Technologies, the responsibility for assembling and testing General Purpose Heat Source (GPHS) radioisotope thermoelectric generators (RTGs). Assembled and tested were five RTGs, which included four flight units and one non-flight qualification unit. Figure 1 shows the RTG, which was designed by General Electric AstroSpace Division (GE/ASD) to produce 285 W of electrical power. A detailed description of the processes for RTG assembly and testing is presented by Amos and Goebel (1989). The RTG performance data are described by Bennett, et al. (1986). The flight units will provide electrical power for the National Aeronautics and Space Administration's (NASA) Galileo mission to Jupiter (two RTGs) and the joint NASA/European Space Agency (ESA) Ulysses mission to study the polar regions of the sun (one RTG). The remaining flight unit will serve as the spare for both missions, and a non-flight qualification unit was assembled and tested to ensure that performance criteria were adequately met. 4 refs., 3 figs.

  10. Thermal vacuum life test facility for radioisotope thermoelectric generators

    Science.gov (United States)

    Deaton, R. L.; Goebel, C. J.; Amos, W. R.

    In the late 1970's, the Department of Energy (DOE) assigned Monsanto Research Corporation, Mound Facility, now operated by EG and G Mound Applied Technologies, the responsibility for assembling and testing General Purpose Heat Source (GPHS) radioisotope thermoelectric generators (RTGs). Assembled and tested were five RTGs, which included four flight units and one non-flight qualification unit. Figure 1 shows the RTG, which was designed by General Electric AstroSpace Division (GE/ASD) to produce 285 W of electrical power. A detailed description of the processes for RTG assembly and testing is presented by Amos and Goebel (1989). The RTG performance data are described by Bennett, et al., (1986). The flight units will provide electrical power for the National Aeronautics and Space Administration's (NASA) Galileo mission to Jupiter (two RTGs) and the joint NASA/European Space Agency (ESA) Ulysses mission to study the polar regions of the sun (one RTG). The remaining flight unit will serve as the spare for both missions, and a non-flight qualification unit was assembled and tested to ensure that performance criteria were adequately met.

  11. An Advanced Turbo-Brayton Converter for Radioisotope Power Systems

    Science.gov (United States)

    Zagarola, Mark V.; Izenson, Michael G.; Breedlove, Jeffrey J.; O'Connor, George M.; Ketchum, Andrew C.; Jetley, Richard L.; Simons, James K.

    2005-02-01

    Past work has shown that Brayton power converters are an attractive option for high power, long-duration space missions. More recently, Creare has shown that Brayton technology could be scaled with high efficiency and specific power to lower power levels suitable for radioisotope power conversion systems. Creare is currently leading the development of an advanced turbo-Brayton converter under NASA's Prometheus Program. The converter design is based on space-proven cryocooler technologies that have been shown to be safe; to provide long, maintenance-free lifetimes; and to have high reliability, negligible vibration emittance, and low EMI/EMC. The predicted performance of a converter at the beginning of life is greater than 20% (including electronic inefficiencies and overhead) with a converter specific power of greater than 8 We/kg for a test unit and greater than 15 We/kg for a flight unit. The degradation in performance over a 14-year mission lifetime is predicted to be negligible, and the primary life limiting factor is not expected to be an issue for greater than twice the mission duration. Work during the last year focused on the material and fabrication issues associated with a high temperature turbine and a lightweight recuperator, and the performance issues associated with the high-temperature insulation and power conversion electronics. The development of the converter is on schedule. Thermal vacuum testing to demonstrate a technology readiness level of 5 is currently planned for 2006.

  12. Assessment of dynamic energy conversion systems for radioisotope heat sources

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, G.R.; Mangeng, C.A.

    1985-06-01

    The use of dynamic conversion systems to convert the heat generated in a 7500 W(t) 90 Sr radioisotopic heat source to electricity is examined. The systems studies were Stirling; Brayton Cycle; three organic Rankines (ORCs) (Barber-Nichols/ORMAT, Sundstrand, and TRW); and an organic Rankine plus thermoelectrics. The systems were ranked for a North Warning System mission using a Los Alamos Multiattribute Decision Theory code. Three different heat source designs were used: case I with a beginning of life (BOL) source temperature of 640 C, case II with a BOL source temperature of 745/sup 0/C, and case III with a BOL source temperature of 945/sup 0/C. The Stirling engine system was the top-ranked system of cases I and II, closely followed by the ORC systems in case I and ORC plus thermoelectrics in case II. The Brayton cycle system was top-ranked for case III, with the Stirling engine system a close second. The use of /sup 238/Pu in heat source sizes of 7500 W(t) was examined and found to be questionable because of cost and material availability and because of additional requirements for analysis of safeguards and critical mass.

  13. Light-weight radioisotope heater unit (LWRHU) impact tests

    Science.gov (United States)

    Reimus, M. A. H.; Rinehart, G. H.; Herrera, A.; Lopez, B.; Lynch, C.; Moniz, P.

    1998-01-01

    The light-weight radioisotope heater unit (LWRHU) is a 238PuO2-fueled heat source designed to provide one thermal watt in each of various locations on a spacecraft. Los Alamos National Laboratory designed, fabricated, and safety tested the LWRHU. The heat source consists of a hot-pressed 238PuO2 fuel pellet, a Pt-30Rh vented capsule, a pyrolytic graphite insulator, and a fineweave-pierced fabric graphite aeroshell assembly. To compare the performance of the LWRHUs fabricated for the Cassini mission with the performance of those fabricated for the Galileo mission, and to determine a failure threshold, two types of impact tests were conducted. A post-reentry impact test was performed on one of 180 flight-quality units produced for the Cassini mission and a series of sequential impact tests using simulant-fueled LWRHU capsules were conducted respectively. The results showed that deformation and fuel containment of the impacted Cassini LWRHU was similar to that of a previously tested Galileo LWRHU. Both units sustained minimal deformation of the aeroshell and fueled capsule; the fuel was entirely contained by the platinum capsule. Sequential impacting, in both end-on and side-on orientations, resulted in increased damage with each subsequent impact. Sequential impacting of the LWRHU appears to result in slightly greater damage than a single impact at the final impact velocity of 50 m/s.

  14. The development of a milliwatt-level radioisotope power source

    Science.gov (United States)

    Bugby, David C.; McBirney, Thomas R.

    1998-01-01

    Future NASA spacecraft for unmanned planetary exploration will be much smaller and require much less power than the large systems used in prior missions. The ``Powerstick'', a miniaturized isotopic electrical power generator, uses a flight-qualified, DoE-manufactured, 1.1 W Radioisotope Heater Unit (RHU) to generate the high temperature sink for a thermoelectric converter (TEC). The TEC generates sufficient electrical power (~40 mW) to trickle-charge an external rechargeable battery pack, which can then be used in low duty cycle, low power applications. The original Powerstick concept (proposed by JPL) was refined at Swales Aerospace (SA), which has: repackaged it, constructed a prototype, and performed limited testing. The prototype Powerstick is 63.5 mm (2.500'') in diameter, 76.2 mm (3.000'') long, and weighs about 0.3 kg (0.66 lb). Structural analysis indicates the Powerstick can easily survive typical launch loads. Thermal analysis indicates that over 70% of the RHU energy enters the TEC. This paper will describe the design and analysis of the Powerstick prototype and present the key test results.

  15. Development of radioisotope tracer technology and nucleonic control system

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Joon Ha; Lee, Myun Joo; Jung, Sung Hee and others

    1999-04-01

    The purpose of this study is to develop the radioisotope tracer technology, which can be used in solving industrial and environmental problems and basic technology of nuclear control systems that are widely used for automation of industrial plants, and to build a strong tracer group to support the local industries. In relation to the tracer technology, the data acquisition system, the column scanning equipment and the detection pig for a leakage test have been developed. In order to use in analyzing data of tracer experiments, a computer program for the analysis of residence time distribution has been created as well. These results were utilized in developing the tracer technologies, such as the column scanning, the flow measurement using the dilution method, the simultaneous monitoring rotational movement of piston rings and the optimization of a waste water treatment facility, and the technologies were successfully demonstrated in the local industrial. The stripper of RFCC reactor has been examined to find an unwanted structure in it by imminent request from the industry. Related to the development of nucleonic control system, the state of art report on the technology has been written and an equipment for the analysis of asphalt content has been developed. (author)

  16. Predictive efficacy of radioisotope voiding cystography for renal outcome

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seok Ki; Lee, Dong Soo; Kim, Kwang Myeung; Choi, Whang; Chung, June Key; Lee, Myung Chul [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2000-04-01

    As vesicoureteral reflux (VUR) could lead to renal functional deterioration when combined with urinary tract infection, we need to decide whether operative anti-reflux treatment should be performed at the time of diagnosis of VUR. Predictive value of radioisotope voiding cystography (RIVCG) for renal outcome was tested. In 35 children (18 males, 17 females), radiologic voiding cystoure-thrography (VCU), RIVCG and DMSA scan were performed. Change in renal function was evaluated using the follow-up DMSA scan, ultrasonography, and clinical information. Discriminant analysis was performed using individual or integrated variables such as reflux amount and extent at each phase of voiding on RIVCG, in addition to age, gender and cortical defect on DMSA scan at the time of diagnosis. Discriminant function was composed and its performance was examined. Reflux extent at the filling phase and reflux amount and extent at postvoiding phase had a significant prognostic value. Total reflux amount was a composite variable to predict prognosis. Discriminant function composed of reflux extent at the filling phase and reflux amount and extent at postvoiding phase showed better positive predictive value and specificity than conventional reflux grading. RIVCG could predict renal outcome by disclosing characteristic reflux pattern during various voiding phases.

  17. Toward high performance radioisotope thermophotovoltaic systems using spectral control

    Science.gov (United States)

    Wang, Xiawa; Chan, Walker; Stelmakh, Veronika; Celanovic, Ivan; Fisher, Peter

    2016-12-01

    This work describes RTPV-PhC-1, an initial prototype for a radioisotope thermophotovoltaic (RTPV) system using a two-dimensional photonic crystal emitter and low bandgap thermophotovoltaic (TPV) cell to realize spectral control. We validated a system simulation using the measurements of RTPV-PhC-1 and its comparison setup RTPV-FlatTa-1 with the same configuration except a polished tantalum emitter. The emitter of RTPV-PhC-1 powered by an electric heater providing energy equivalent to one plutonia fuel pellet reached 950 °C with 52 W of thermal input power and produced 208 mW output power from 1 cm2 TPV cell. We compared the system performance using a photonic crystal emitter to a polished flat tantalum emitter and found that spectral control with the photonic crystal was four times more efficient. Based on the simulation, with more cell areas, better TPV cells, and improved insulation design, the system powered by a fuel pellet equivalent heat source is expected to reach an efficiency of 7.8%.

  18. Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    Science.gov (United States)

    Anderson, William G.; Tarau, Calin

    2008-01-01

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling convertor provides this cooling. If the Stirling engine stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) was designed to allow multiple stops and restarts of the Stirling engine. A VCHP turns on with a delta T of 30 C, which is high enough to not risk standard ASRG operation but low enough to save most heater head life. This VCHP has a low mass, and low thermal losses for normal operation. In addition to the design, a proof-of-concept NaK VCHP was fabricated and tested. While NaK is normally not used in heat pipes, it has an advantage in that it is liquid at the reservoir operating temperature, while Na or K alone would freeze. The VCHP had two condensers, one simulating the heater head, and the other simulating the radiator. The experiments successfully demonstrated operation with the simulated heater head condenser off and on, while allowing the reservoir temperature to vary over 40 to 120 C, the maximum range expected. In agreement with previous NaK heat pipe tests, the evaporator delta T was roughly 70 C, due to distillation of the NaK in the evaporator.

  19. Polyvinyl acetate/poly(amide-12-b-ethylene oxide) blend membranes for carbon dioxide separation

    Institute of Scientific and Technical Information of China (English)

    Shichao; Feng; Jizhong; Ren; Hui; Li; Kaisheng; Hua; Xinxue; Li; Maicun; Deng

    2013-01-01

    In this paper,blend membranes from polyvinyl acetate(PVAc)and block copolymer poly(amide-12-b-ethylene oxide)(Pebax1074)are prepared by solution casting and solvent evaporation method.Although they are homogeneous on a macro-scale,the observations from DSC and SEM indicate micro-phase separation for PVAc/Pebax1074 blend membranes.With the increase of Pebax1074 content,gas permeabilities of CO2,H2,N2and CH4all increase greatly.PVAc/Pebax1074 blend membranes with high PVAc content are appropriate for CO2/CH4separation.The temperature dependence of gas permeability is divided into rubbery region and glassy region.The activation energies of permeation in rubbery region are smaller than those in glassy region,and they all decrease with increasing Pebax1074 content.For N2,H2and CH4,their gas permeation properties are mainly influenced by the dual-mode sorption and hydrostatic pressure effect.But for CO2,its permeability increases with the increase of pressure due to CO2-induced plasticization effect,which is more obvious for PVAc/Pebax1074 blend membranes with high PVAc content.

  20. Wood decay in desert riverine environments

    Science.gov (United States)

    Andersen, Douglas; Stricker, Craig A.; Nelson, S. Mark

    2016-01-01

    Floodplain forests and the woody debris they produce are major components of riverine ecosystems in many arid and semiarid regions (drylands). We monitored breakdown and nitrogen dynamics in wood and bark from a native riparian tree, Fremont cottonwood (Populus deltoides subsp. wislizeni), along four North American desert streams. We placed locally-obtained, fresh, coarse material [disks or cylinders (∼500–2000 cm3)] along two cold-desert and two warm-desert rivers in the Colorado River Basin. Material was placed in both floodplain and aquatic environments, and left in situ for up to 12 years. We tested the hypothesis that breakdown would be fastest in relatively warm and moist aerobic environments by comparing the time required for 50% loss of initial ash-free dry matter (T50) calculated using exponential decay models incorporating a lag term. In cold-desert sites (Green and Yampa rivers, Colorado), disks of wood with bark attached exposed for up to 12 years in locations rarely inundated lost mass at a slower rate (T50 = 34 yr) than in locations inundated during most spring floods (T50 = 12 yr). At the latter locations, bark alone loss mass at a rate initially similar to whole disks (T50 = 13 yr), but which subsequently slowed. In warm-desert sites monitored for 3 years, cylinders of wood with bark removed lost mass very slowly (T50 = 60 yr) at a location never inundated (Bill Williams River, Arizona), whereas decay rate varied among aquatic locations (T50 = 20 yr in Bill Williams River; T50 = 3 yr in Las Vegas Wash, an effluent-dominated stream warmed by treated wastewater inflows). Invertebrates had a minor role in wood breakdown except at in-stream locations in Las Vegas Wash. The presence and form of change in nitrogen content during exposure varied among riverine environments. Our results suggest woody debris breakdown in desert riverine ecosystems is primarily a microbial process with rates determined by landscape position

  1. Use of carbon and AlPO4 dual coating on H2Ti12O25 anode for high stability hybrid supercapacitor

    Science.gov (United States)

    Kim, Jin-Hyeon; Lee, Seung-Hwan

    2016-11-01

    We fabricated the cylindrical hybrid supercapacitors using the pristine H2Ti12O25, carbon coated H2Ti12O25, AlPO4 coated H2Ti12O25, AlPO4-carbon hybrid coated H2Ti12O25, and AlPO4-carbon dual coated H2Ti12O25 as anodes. The electrochemical performances and thermal stability of the hybrid supercapacitors with different surface-modified anodes were investigated. The uniform and ultrathin dual coated H2Ti12O25 maximizes the electrochemical performances with superior thermal stability. The dual coating layer acts as a bridge for the Li ion diffusion and electron conduction and as a barrier to suppress swelling phenomenon from HF attack. Moreover, the partially AlF3 areas at AlPO4 layer, due to the reaction with HF, have positive effects on electrochemical performances. Therefore, the novel design composed of carbon and AlPO4 can be regarded as an effective strategy for anode used in hybrid supercapacitors.

  2. FY12 ARRA-NRAP Report – Studies to Support Risk Assessment of Geologic Carbon Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, Kirk J.; Shao, Hongbo; Thompson, C. J.; Zhong, Lirong; Jung, Hun Bok; Um, Wooyong

    2011-09-27

    This report summarizes results of research conducted during FY2012 to support the assessment of environmental risks associated with geologic carbon dioxide (CO2) sequestration and storage. Several research focus areas are ongoing as part of this project. This includes the quantification of the leachability of metals and organic compounds from representative CO2 storage reservoir and caprock materials, the fate of metals and organic compounds after release, and the development of a method to measure pH in situ under supercritical CO2 (scCO2) conditions. Metal leachability experiments were completed on 6 different rock samples in brine in equilibrium with scCO2 at representative geologic reservoir conditions. In general, the leaching of RCRA metals and other metals of concern was found to be limited and not likely to be a significant issue (at least, for the rocks tested). Metals leaching experiments were also completed on 1 rock sample with scCO2 containing oxygen at concentrations of 0, 1, 5, and 10% to simulate injection of CO2 originating from the oxy-fuel combustion process. Significant differences in the leaching behavior of certain metals were observed when oxygen is present in the CO2. These differences resulted from oxidation of sulfides, release of sulfate, ferric iron and other metals, and subsequent precipitation of iron oxides and some sulfates such as barite. Experiments to evaluate the potential for mobilization of organic compounds from representative reservoir materials and cap rock and their fate in porous media (quartz sand) have been conducted. Results with Fruitland coal and Gothic shale indicate that lighter organic compounds were more susceptible to mobilization by scCO2 compared to heavier compounds. Alkanes demonstrated very low extractability by scCO2. No significant differences were observed between the extractability of organic compounds by dry or water saturated scCO2. Reaction equilibrium appears to have been reached by 96 hours. When

  3. Properties of nylon 12 balloons after thermal and liquid carbon dioxide treatments.

    Science.gov (United States)

    Ro, Andrew J; Davé, Vipul

    2013-03-01

    Critical design attributes of angioplasty balloons include the following: tear resistance, high burst pressures, controlled compliance, and high fatigue. Balloons must have tear resistance and high burst pressures because a calcified stenosis can be hard and nominal pressures of up to 16 atm can be used to expand the balloon. The inflated balloon diameter must be a function of the inflation pressure, thus compliance is predictable and controlled. Reliable compliance is necessary to prevent damage to vessel walls, which may be caused by over-inflation. Balloons are often inflated multiple times in a clinical setting and they must be highly resistant to fatigue. These design attributes are dependent on the mechanical properties and polymer morphology of the balloon. The effects of residual stresses on shrinkage, crystallite orientation, balloon compliance, and mechanical properties were studied for angioplasty nylon 12 balloons. Residual stresses of these balloons were relieved by oven heat treatment and liquid CO2 exposure. Residual stresses were measured by quantifying shrinkage at 80 °C of excised balloon samples using a dynamic mechanical analyzer. Shrinkage was lower after oven heat treatment and liquid CO2 exposure compared to the as-received balloons, in the axial and radial directions. As-received, oven heat treated, and liquid CO2-exposed balloon samples exhibited similar thermal properties (T(g), T(m), X(t)). Crystallite orientation was not observed in the balloon cylindrical body using X-ray scattering and polarized light microscopy, which may be due to balloon fabrication conditions. Significant differences were not observed between the stress-strain curves, balloon compliance, and average burst pressures of the as-received, oven heat treated, and liquid CO2-exposed balloons.

  4. Exploring the simplest purely baryonic decay processes

    CERN Document Server

    Geng, C Q; Rodrigues, Eduardo

    2016-01-01

    We propose to search for purely baryonic decay processes at the LHCb experiment. In particular, we concentrate on the decay $\\Lambda_b^0\\to p\\bar pn$, which is the simplest purely baryonic decay mode, with solely spin-1/2 baryons involved. We predict its decay branching ratio to be ${\\cal B}(\\Lambda_b^0\\to p\\bar pn)=(2.0^{+0.3}_{-0.2})\\times 10^{-6}$, which is sufficiently large to make the decay mode accessible to LHCb. Though not considered in general, purely baryonic decays could shed light on the puzzle of the baryon number asymmetry in the universe by means of a better understanding of the baryonic nature of our matter world. As such, they constitute a yet unexplored class of decay processes worth investigating. Our study can be extended to the purely baryonic decays of $\\Lambda_b^0\\to p\\bar p \\Lambda$, $\\Lambda_b^0\\to \\Lambda \\bar p\\Lambda$ and $\\Lambda_b^0\\to \\Lambda\\bar \\Lambda\\Lambda$, as well as other similar anti-triplet $b$-baryon decays, such as $\\Xi_b^{0,-}$.

  5. Radioisotope scanning of brain, liver, lung and bone with a note on tumour localizing agents

    Science.gov (United States)

    Lavender, J. P.

    1973-01-01

    Radioisotopic scanning of brain, liver, lungs and the skeleton is briefly reviewed with a survey of recent developments of clinical significance. In brain scanning neoplasm detection rates of greater than 90% are claimed. The true figure is probably 70-80%. Autopsy data shows a number of false negatives, particularly with vascular lesions. Attempts to make scanning more specific in differentiating neoplasm from vascular lesions by rapid sequence blood flow studies are reviewed. In liver scanning by means of colloids again high success rate is claimed but small metastases are frequently missed and the false negative scan rate is probably quite high. Lung scanning still has its main place in investigating pulmonary embolic disease. Ventilation studies using Xenon 133 are useful, particularly combined with perfusion studies. The various radiopharmaceuticals for use in bone scanning are reviewed. The appearance of technetium labelled phosphate compounds will probably allow much wider use of total skeletal scanning. Research into tumour localizing agents continues, the most recent and interesting being Gallium citrate and labelled bleomycin. Neither agent is predictable however although Gallium may have a place in Hodgkins disease and bronchogenic neoplasm and both may have a place in the detection of cerebral tumours. ImagesFig. 1Fig. 2Fig. 3p452-bFig. 3bFig. 4Fig. 5Fig. 5bFig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 12c & 12dFig. 13Fig. 13 b,c,dFig. 14Fig. 14bFig. 15Fig. 15bFig. 16Fig. 17Fig. 18 PMID:4602127

  6. Influence of different carbon sources on exopolysaccharide production by Lactobacillus delbrueckii subsp. bulgaricus (B3, G12 and Streptococcus thermophilus (W22

    Directory of Open Access Journals (Sweden)

    Zehra Nur Yuksekdag

    2008-06-01

    Full Text Available Exopolysaccharides (EPSs production was studied by Lactobacillus delbrueckii subsp. bulgaricus (B3, G12 and Streptococcus thermophilus (W22 in the medium containing various carbon sources (glucose, fructose, sucrose or lactose. For all the strains, glucose was the most efficient carbon source and B3, G12 and W22 strains produced 211, 175 and 120 EPS mg/L respectively. Also, the influence of different concentrations of glucose (5,10,15,20,25,30 g/L on EPS production and growth was studied. The results indicated that EPS production and growth were stimulated by the high glucose concentration (30 g/L.

  7. Radioisotope Power System Delivery, Ground Support and Nuclear Safety Implementation: Use of the Multi-Mission Radioisotope Thermoelectric Generator for the NASA's Mars Science Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    S.G. Johnson; K.L. Lively; C.C. Dwight

    2014-07-01

    Radioisotope power systems have been used for over 50 years to enable missions in remote or hostile environments. They are a convenient means of supplying a few milliwatts up to a few hundred watts of useable, long-term electrical power. With regard to use of a radioisotope power system, the transportation, ground support and implementation of nuclear safety protocols in the field is a complex process that requires clear identification of needed technical and regulatory requirements. The appropriate care must be taken to provide high quality treatment of the item to be moved so it arrives in a condition to fulfill its missions in space. Similarly it must be transported and managed in a manner compliant with requirements for shipment and handling of special nuclear material. This presentation describes transportation, ground support operations and implementation of nuclear safety and security protocols for a radioisotope power system using recent experience involving the Multi-Mission Radioisotope Thermoelectric Generator for National Aeronautics and Space Administration’s Mars Science Laboratory, which launched in November of 2011.

  8. Using a non-radioisotopic, quantitative TRAP-based me thod detecting telomerase activities in human hepatoma cells

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A non-radioisotopic, quantitative TRAP-based telom erase activity assay was established mainly by using SYBR Green-I staining instead of radioisotope. Comparing with conventional radioisotope based method, it was better in reproducibility and accuracy. Using this method, we found telomerase activities were absent in normal human liver cells, while detected in all of four human hepatoma cell lines (BEL-7404, SMMC-7721, QGY-7903 and HCCM) without significant differences.

  9. Current status of production and research of radioisotopes and radiopharmaceuticals in Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Soenarjo, Sunarhadijoso; Tamat, Swasono R. [Center for Development of Radioisotopes and Radiopharmaceuticals, National Nuclear Energy Agency (BATAN), Kawasan Puspiptek, Serpong, Tangerang (Indonesia)

    2000-10-01

    The use of radioactive preparation in Indonesia has sharply increased during the past years, indicated by increase of the number of companies utilizing radioisotopes during 1985 to 1999. It has been clearly stressed in the BATAN's Strategic Plan for 1994-2014 that the production of radioisotopes and radiopharmaceuticals is one of five main industrial fields within the platform of the Indonesian nuclear industry. Research programs supporting the production of radioisotopes and radiopharmaceuticals as well as development of production technology are undertaken by the Research Center for Nuclear Techniques (RCNT) in Bandung and by the Radioisotope Production Center (RPC) in Serpong, involving cooperation with other research center within BATAN, universities and hospitals as well as overseas nuclear research institution. The presented paper describes production and research status of radioisotopes and radiopharmaceuticals in Indonesia after the establishment of P.T. Batan Teknologi in 1996, a government company assigned for activities related to the commercial application of nuclear technology. The reviewed status is divided into two short periods, i.e. before and after the Chairman Decree No. 73/KA/IV/1999 declaring new BATAN organizational structure. Subsequent to the Decree, all commercial requests for radioisotopes and radiopharmaceuticals are fulfilled by P.T. Batan Teknologi, while demands on novel radioactive preparations or new processing technology, as well as research and development activities should be fulfilled by the Center for the Development of Radioisotopes and Radiopharmaceuticals (CDRR) through non-commercial arrangement. The near-future strategic research programs to response to dynamic public demand are also discussed. The status of research cooperation with JAERI (Japan) is also reported. (author)

  10. Preparation of Cerium (III) 12-tungstophosphoric acid/ordered mesoporous carbon composite modified electrode and its electrocatalytic properties

    Energy Technology Data Exchange (ETDEWEB)

    Liu Lin [Faculty of Chemistry, Northeast Normal University, Changchun 130024 (China); Ndamanisha, Jean Chrysostome [Universite du Burundi, Institut de pedagogie appliquee, B.P 5223 Bujumbura (Burundi); Bai Jing [Faculty of Chemistry, Northeast Normal University, Changchun 130024 (China); Guo Liping, E-mail: guolp078@nenu.edu.c [Faculty of Chemistry, Northeast Normal University, Changchun 130024 (China)

    2010-03-30

    In this work, a novel structured Cerium (III) 12-tungstophosphoric acid (CePW)/ordered mesoporous carbon (OMC) composite is synthesized. The characterization of the material by the Fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and electrochemical characterization shows that the novel CePW/OMC composite has improved properties based on the combination of CePW and OMC properties. CePW/OMC can be used to modify the glassy carbon (GC) electrode and the CePW/OMC/GC modified electrode shows an enhanced electrocatalytic activity. This property can be applied in the determination of some biomolecules. Especially, the detection and determination of the guanine (G) in the presence of adenine (A) is achieved. The catalytic current of G versus its concentration shows a good linearity with two good linear ranges from 4.0 x 10{sup -6} to 8.0 x 10{sup -5} M and from 8.0 x 10{sup -5} to 1.9 x 10{sup -3} M (correlation coefficient = 0.999 and 0.996) with a detection limit of 5.7 x 10{sup -9} M (S/N = 3). The linear range for adenine is 4.0 x 10{sup -6}-7.0 x 10{sup -4} M with a detection limit of 7.45 x 10{sup -8} M. With good stability and reproducibility, the present CePW/OMC/GC modified electrode should be a good model for constructing a novel and promising electrochemical sensing platform for further electrochemical detection of other biomolecules.

  11. Small Radioisotope Power System Testing at NASA Glenn Research Center

    Science.gov (United States)

    Dugala, Gina; Bell, Mark; Oriti, Salvatore; Fraeman, Martin; Frankford, David; Duven, Dennis

    2013-01-01

    In April 2009, NASA Glenn Research Center (GRC) formed an integrated product team (IPT) to develop a Small Radioisotope Power System (SRPS) utilizing a single Advanced Stirling Convertor (ASC) with passive balancer. A single ASC produces approximately 80 We making this system advantageous for small distributed lunar science stations. The IPT consists of Sunpower, Inc., to provide the single ASC with a passive balancer, The Johns Hopkins University Applied Physics Laboratory (JHUAPL) to design an engineering model Single Convertor Controller (SCC) for an ASC with a passive balancer, and NASA GRC to provide technical support to these tasks and to develop a simulated lunar lander test stand. The single ASC with a passive balancer, simulated lunar lander test stand, and SCC were delivered to GRC and were tested as a system. The testing sequence at GRC included SCC fault tolerance, integration, electromagnetic interference (EMI), vibration, and extended operation testing. The SCC fault tolerance test characterized the SCCs ability to handle various fault conditions, including high or low bus power consumption, total open load or short circuit, and replacing a failed SCC card while the backup maintains control of the ASC. The integrated test characterized the behavior of the system across a range of operating conditions, including variations in cold-end temperature and piston amplitude, including the emitted vibration to both the sensors on the lunar lander and the lunar surface. The EMI test characterized the AC and DC magnetic and electric fields emitted by the SCC and single ASC. The vibration test confirms the SCCs ability to control the single ASC during launch. The extended operation test allows data to be collected over a period of thousands of hours to obtain long term performance data of the ASC with a passive balancer and the SCC. This paper will discuss the results of each of these tests.

  12. Radioisotope Productions for Medical Use with Accelerator Neutrons

    Science.gov (United States)

    Minato, Futoshi; Nagai, Yasuki; Iwamoto, Nobuyuki; Iwamoto, Osamu

    2014-09-01

    Various kinds of radioactive isotopes (RIs) are widely used in nuclear medicine for diagnostics and therapy. Since the RIs are not usually present in the nature, they must be produced by nuclear reactors and accelerators. For instance, 99mTc, which is the most common RI used in diagnosis, is mainly produced by fission of highly enriched 235U (HEU) in nuclear reactors. However, use of the HEU is unfavorable in terms of nuclear security. Therefore, many methods without 235U have been studied in order to produce RIs for medical use; for example, thermal neutron capture, gamma disintegration, and proton induced reactions. We also have proposed an alternative method using accelerator neutrons besides the above methods. Technique producing high intense accelerator neutron beam as much as 1015 n/s is being developed and RI productions with the accelerator neutron have been done recently. The major advantages of the use of accelerator neutron are followings. 1) A wide variety of carrier-added and carrier-free radioisotopes can be produced using the neutrons, because a charge exchange reaction of a sample nucleus has a sizable cross section of 50 to 500 mb. 2) High transparency of neutron allows us to use a large amount of sample to co-produce other RIs by putting other samples behind the main sample in the beam direction. In this talk, we will show the features of RI productions with accelerator neutron which we have ever investigated and found, along with numerical results of RI yields calculated with Japanese Evaluated Nuclear Data Library (JENDL-4.0).

  13. The Texas A&M Radioisotope Production and Radiochemistry Program

    Energy Technology Data Exchange (ETDEWEB)

    Akabani, Gamal [Texas A & M Univ., College Station, TX (United States)

    2016-08-31

    The main motivation of the project at Texas A&M University was to carry out the production of critically needed radioisotopes used in medicine for diagnostic and therapy, and to establish an academic program in radionuclide production and separation methods. After a lengthy battle with the Texas A&M University Radiation Safety Office, the Texas Department of State Health Services granted us a license for the production of radionuclides in July 2015 allowing us to work in earnest in our project objectives. Experiments began immediately after licensing and we started the assembly and testing of our target systems. There were four analytical/theoretical projects and two experimental target systems. These were for At-211 production and for Zn- 62/Cu-62 production. The theoretical projects were related to the production of Mo-99/Tc-99m using a) a subcritical aqueous target system and b) production of Tc-99m from accelerator generated Mo-99 utilizing a photon-neutron interaction with enriched Mo-100 targets. The two experimental projects were the development of targetry systems and production of At-211 and Zn-62/Cu-62 generator. The targetry system for At-211 has been tested and production of At-211 is chronic depending of availability of beam time at the cyclotron. The installation and testing of the targetry system for the production of Zn-62/Cu-62 has not been finalized. A description of the systems is described. The academic program in radionuclide production and separation methods was initiated in the fall of 2011 and due to the lack of a radiochemistry laboratory it was suspended. We expect to re-start the academic program at the Texas A&M Institute for Preclinical Studies under the Molecular Imaging Program.

  14. The Texas A&M Radioisotope Production and Radiochemistry Program

    Energy Technology Data Exchange (ETDEWEB)

    Akabani, Gamal [Texas A & M Univ., College Station, TX (United States). Dept. of Nuclear Engineering. Dept. of Veterinary Integrative Biosciences

    2016-10-28

    The main motivation of the project at Texas A&M University was to carry out the production of critically needed radioisotopes used in medicine for diagnostics and therapy, and to establish an academic program in radionuclide production and separation methods. After a lengthy battle with the Texas A&M University Radiation Safety Office, the Texas Department of State Health Services granted us a license for the production of radionuclides in July 2015, allowing us to work in earnest in our project objectives. Experiments began immediately after licensing, and we started the assembly and testing of our target systems. There were four analytical/theoretical projects and two experimental target systems. These were for At-211 production and for Zn-62/Cu-62 production. The theoretical projects were related to the production of Mo-99/Tc-99m using a) a subcritical aqueous target system and b) production of Tc-99m from accelerator generated Mo-99 utilizing a photon-neutron interaction with enriched Mo-100 targets. The two experimental projects were the development of targetry systems and production of At-211 and Zn-62/Cu-62 generator. The targetry system for At-211 has been tested and production of At-211 is chronic depending of availability of beam time at the cyclotron. The installation and testing of the targetry system for the production of Zn-62/Cu-62 has not been finalized. A description of the systems is described. The academic program in radionuclide production and separation methods was initiated in the fall of 2011 and due to the lack of a radiochemistry laboratory it was suspended. We expect to re-start the academic program at the Texas A&M Institute for Preclinical Studies under the Molecular Imaging Program.

  15. The Texas A&M Radioisotope Production and Radiochemistry Program

    Energy Technology Data Exchange (ETDEWEB)

    Akabani, Gamal [Texas A & M Univ., College Station, TX (United States)

    2016-08-31

    The main motivation of the project at Texas A&M University was to carry out the production of critically needed radioisotopes used in medicine for diagnostic and therapy, and to establish an academic program in radionuclide production and separation methods. After a lengthy battle with the Texas A&M University Radiation Safety Office, the Texas Department of State Health Services granted us a license for the production of radionuclides in July 2015, allowing us to work in earnest in our project objectives. Experiments began immediately after licensing, and we started the assembly and testing of our target systems. There were four analytical/theoretical projects and two experimental target systems. These were for At-211 production and for Zn- 62/Cu-62 production. The theoretical projects were related to the production of Mo-99/Tc-99m using (a) a subcritical aqueous target system and (b) production of Tc-99m from accelerator-generated Mo-99 utilizing a photon-neutron interaction with enriched Mo-100 targets. The two experimental projects were the development of targetry systems and production of At-211 and Zn-62/Cu-62 generator. The targetry system for At-211 has been tested and production of At-211 is chronic depending of availability of beam time at the cyclotron. The installation and testing of the targetry system for the production of Zn-62/Cu-62 has not been finalized. A description of the systems is described. The academic program in radionuclide production and separation methods was initiated in the fall of 2011; due to the lack of a radiochemistry laboratory, it was suspended. We expect to re-start the academic program at the Texas A&M Institute for Preclinical Studies under the Molecular Imaging Program.

  16. decays to baryons

    Indian Academy of Sciences (India)

    Torsten Leddig

    2012-11-01

    From inclusive measurements, it is known that about 7% of all mesons decay into final states with baryons. In these decays, some striking features become visible compared to mesonic decays. The largest branching fractions come with quite moderate multiplicities of 3–4 hadrons. We note that two-body decays to baryons are suppressed relative to three- and four-body decays. In most of these analyses, the invariant baryon–antibaryon mass shows an enhancement near the threshold. We propose a phenomenological interpretation of this quite common feature of hadronization to baryons.

  17. Weak decays. [Lectures, phenomenology

    Energy Technology Data Exchange (ETDEWEB)

    Wojcicki, S.

    1978-11-01

    Lectures are given on weak decays from a phenomenological point of view, emphasizing new results and ideas and the relation of recent results to the new standard theoretical model. The general framework within which the weak decay is viewed and relevant fundamental questions, weak decays of noncharmed hadrons, decays of muons and the tau, and the decays of charmed particles are covered. Limitation is made to the discussion of those topics that either have received recent experimental attention or are relevant to the new physics. (JFP) 178 references

  18. Investigation of carbon-coated lithiated Li{sub 4+x}Ti{sub 5}O{sub 12}/C for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Mengjie; Zhang, Lin; Gong, Lijun; Liu, Hongbo; Chen, Yuxi, E-mail: yxchen@hnu.edu.cn

    2015-11-15

    Highlights: • Lithiated Li{sub 4+x}Ti{sub 5}O{sub 12}/C with pre-stored active Li ions has been synthesized. • The first-cycle coulombic efficiency of Li{sub 4+x}Ti{sub 5}O{sub 12}/C is over 100%. • Li{sub 4+x}Ti{sub 5}O{sub 12}/C displays excellent cyclic stability and capacity retention. • TiO{sub 2} nanoparticles and carbon coating are necessary for formation of Li{sub 4+x}Ti{sub 5}O{sub 12}/C. - Abstract: Carbon-coated Li{sub 4}Ti{sub 5}O{sub 12} and lithiated Li{sub 4+x}Ti{sub 5}O{sub 12} anode materials have been synthesized using nanosized anatase TiO{sub 2} and commercial TiO{sub 2} with mixed structure as Ti sources, respectively. Microstructural investigation indicates that Li{sub 4}Ti{sub 5}O{sub 12} and Li{sub 4+x}Ti{sub 5}O{sub 12} are covered by amorphous carbon layers with thickness of 2–3 nm. Their electrochemical performance has been evaluated, which indicates that an amount of active Li ions have been pre-stored in the Li{sub 4+x}Ti{sub 5}O{sub 12} lattice during solid-state synthesis, resulting in its first-cycle coulombic efficiency over 100%. Further, Li{sub 4+x}Ti{sub 5}O{sub 12}/C exhibits higher cyclic capacities than Li{sub 4}Ti{sub 5}O{sub 12}/C at different current density. The reversible charge capacity retention of Li{sub 4+x}Ti{sub 5}O{sub 12}/C reaches 98.5% after 100 cycles, which indicates that Li{sub 4+x}Ti{sub 5}O{sub 12}/C is promising candidate anode material for long lifetime lithium-ion batteries. The formation mechanism of Li{sub 4+x}Ti{sub 5}O{sub 12}/C has been discussed, in which the nanosized anatase TiO{sub 2} with high chemical activity and the carbon coating play key roles for the formation of Li{sub 4+x}Ti{sub 5}O{sub 12}/C.

  19. Metal-Free Oxidation of α-Hydroxy Ketones to 1,2-Diketones Catalyzed by Mesoporous Carbon Nitride with Visible Light

    Institute of Scientific and Technical Information of China (English)

    郑志硕; 周小松

    2012-01-01

    As a photocatalyst, mesoporous carbon nitride (mpg-C3N4) shows higher photocatalytic activities in organic synthesis. Herein we report an mpg-C3N4-catalyzed oxidation of α-hydroxy ketones to synthesize 1,2-diketones using visible light. This transformation represents a green and highly efficient synthetic route to synthesize 1,2-diketones for which catalytic approaches are scarce.

  20. Annual Technical Progress Report of the Radioisotope Power Systems Materials Production and Technology Program Tasks for October 1, 2008 through September 30, 2009

    Energy Technology Data Exchange (ETDEWEB)

    King, James F [ORNL

    2010-05-01

    The Office of Space and Defense Power Systems of the U. S. Department of Energy (DOE) provides Radioisotope Power Systems (RPS) for applications where conventional power systems are not feasible. For example, radioisotope thermoelectric generators (RTG) were supplied by the DOE to the National Aeronautics and Space Administration (NASA) for deep space missions including the Cassini Mission launched in October of 1997 to study the planet Saturn. For the Cassini Mission, the Oak Ridge National Laboratory (ORNL) produced carbon-bonded carbon fiber (CBCF) insulator sets, iridium alloy blanks and foil, and clad vent sets (CVS) used in the generators. ORNL has been involved in developing materials and technology and producing components for the DOE for more than three decades. This report reflects program guidance from the Office of Space and Defense Power Systems for fiscal year (FY) 2009. Production activities for prime quality (prime) CBCF insulator sets, iridium alloy blanks and foil, and CVS are summarized in this report. Technology activities are also reported that were conducted to improve the manufacturing processes, characterize materials, or to develop information for new RPS.

  1. Estimates of helium gas release in 238PuO 2 fuel particles for radioisotope heat sources and heater units

    Science.gov (United States)

    El-Genk, Mohamed S.; Tournier, Jean-Michel

    2000-06-01

    Release data of noble gases (Xe and Kr) from small-grain (7-40 μm), large-grain (⩾300 μm), and monocrystal UO 2 fuel particles, during isothermal irradiation up to 6.4 at.% and 2030 K are reviewed and their applicability to estimate helium release from 238PuO 2 fuel particles (⩾300 μm in diameter) is examined. Coated 238PuO 2 particles have recently been proposed for use in radioisotope power systems and heater units employed in planetary exploration missions. These fuel particles are intentionally sized and designed to prevent any adverse radiological effect and retain the helium gas generated by the radioactive decay of 238Pu, a desired feature for some planetary missions. Results suggest that helium release from large-grain (⩾300 μm) particles of K could be 80% but less than 7% at 1042 K, which is in general agreement with the experiments conducted at Los Alamos National Laboratory more than two decades ago. In these experiments, the helium gas release from small-grain (7-40 μm) 238PuO 2 fuel pellets has been measured during steady-state heating at temperatures up to 1886 K and ramp heating to 1723 K.

  2. Reentry response of the light weight radioisotope heater unit resulting from a Venus-Earth-Earth Gravity Assist maneuver accident

    Energy Technology Data Exchange (ETDEWEB)

    Hagan, J.C.

    1988-10-01

    Reentry analyses consisting of ablation response, thermal response and thermal stress response have been conducted on the Light Weight Radioisotope Heater Unit for Galileo/VEEGA reentry conditions. Sequential ablation analyses of the LWRHU aeroshell, the fuel clad, and the fuel pellet have been conducted in reentry regimes where the aeroshell has been deemed to fail. The failure criterion for ablation is assumed to be recession corresponding to 50% of the wall thickness (the design criterion recommended in the DOE Overall Safety Manual). Although the analyses have been carried far beyond this limit (as presented and discussed herein), JHU/APL endorses the position that failure may occur at the time that this recession is achieved or at lower altitudes within the heat pulse considering the uncertainties in the aerodynamic, thermodynamic, and thermo-structural analyses and modeling. These uncertainties result mainly because of the high energies involved in the VEEGA reentries compared to orbital decay reentries. Risk evaluations should consider the fact that for shallow flight paths the unit may disassemble at high-altitude as a result of ablation or may remain intact until it impacts with a clad that had been molten. 80 refs., 46 figs., 16 tabs.

  3. Planning For Multiple NASA Missions With Use Of Enabling Radioisotope Power

    Energy Technology Data Exchange (ETDEWEB)

    S.G. Johnson; K.L. Lively; C.C. Dwight

    2013-02-01

    Since the early 1960’s the Department of Energy (DOE) and its predecessor agencies have provided radioisotope power systems (RPS) to NASA as an enabling technology for deep space and various planetary missions. They provide reliable power in situations where solar and/or battery power sources are either untenable or would place an undue mass burden on the mission. In the modern era of the past twenty years there has been no time that multiple missions have been considered for launching from Kennedy Space Center (KSC) during the same year. The closest proximity of missions that involved radioisotope power systems would be that of Galileo (October 1989) and Ulysses (October 1990). The closest that involved radioisotope heater units would be the small rovers Spirit and Opportunity (May and July 2003) used in the Mars Exploration Rovers (MER) mission. It can be argued that the rovers sent to Mars in 2003 were essentially a special case since they staged in the same facility and used a pair of small launch vehicles (Delta II). This paper examines constraints on the frequency of use of radioisotope power systems with regard to launching them from Kennedy Space Center using currently available launch vehicles. This knowledge may be useful as NASA plans for its future deep space or planetary missions where radioisotope power systems are used as an enabling technology. Previous descriptions have focused on single mission chronologies and not analyzed the timelines with an emphasis on multiple missions.

  4. Reflections on the juridical implications of the medical use of radiations and radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Ana Celia P.P. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Faculdade de Direito]. E-mails: anaceu2000@yahoo.com.br; Cuperschmid, Ethel Mizrahy [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Centro de Memoria da Medicina - CEMMOR]. E-mail: ethel.mizrahy@yahoo.com; Campos, Tarcisio P. Ribeiro de [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares]. E-mail: campos@nuclear.ufmg.br

    2007-07-01

    The pacific use of radiation and radioisotopes for the society presents radiological risks, due its capacity to produce damage to environmental and human being, contrasting with its high economic and social benefits. In the face of the risk, juridical system leans over to reach the required regulations that implies in the balance between human and environmental security and the expected improvements of the medical nuclear techniques. The Brazilian Constitution of 1988 tries to provide the normalization for the application of the nuclear energy and its radioisotopes. However, target as a strategically technology and due to its expansion, its regulations still deserves analyses and reflections. The present paper starts from the Constitution presenting the references about the theme and analyzing it. It is addressed the principle of the objective civil responsibility making analyses on the use of radiations and radioisotope on the medicine. It addresses the role of federal autonomy related to the 'MCT - Ministerio de Ciencia e Tecnologia' with its accumulative functions in society, such as scientific and technologic development, education, and its own focalization. The recent opening of the monopoly for the production of radioisotopes for very short half-lives is also discussed. It makes a comparison between juridical aspects of Brazil with international system. The present article contributes to open same topics of discussions on the Brazilian juridical aspects involving radiations and radioisotopes application on medicine. (author)

  5. Are radioisotope shortages a thing of the past?

    Energy Technology Data Exchange (ETDEWEB)

    Peykov, Pavel; Cameron, Ron [OECD Nuclear Energy Agency, Issy-les-Moulineaux (France)

    2014-10-15

    Since June 2009, the NEA and its High-level Group on the Security of Supply of Medical Radioisotopes (HLG-MR) have examined the causes of {sup 99}Mo/{sup 99m}Tc supply shortages and developed a policy approach, including principles and supporting recommendations to address those causes. The NEA has also reviewed the global {sup 99}Mo/{sup 99m}Tc supply situation periodically, using the most up-to-date data from supply chain participants, to highlight periods of reduced supply and underscore the case for implementing the HLG-MR policy approach in a timely and globally-consistent manner. In 2012, the NEA released a {sup 99}Mo supply and demand update for the period up to 2030 (A Supply and Demand Update of the Molybdenum-99 Market, OECD/NEA, 2012), identifying periods of low supply relative to demand. This paper presents the preliminary results from an updated {sup 99}Mo supply and demand forecast, focusing on the potentially critical 2015-2020 period, when two major {sup 99}Mo producers (the NRU reactor in Canada and the OSIRIS reactor in France) are scheduled to cease {sup 99}Mo irradiations. On the demand side, the NEA had previously released a study with the results from a global survey of future demand for {sup 99}Mo/{sup 99m}Tc (OECD-NEA, 2011), devising a scenario based on a data assessment by an expert advisory group. In the current analysis, the expected demand growth rate and total demand have been modified, based on the latest information from supply chain participants. On the supply side, the NEA has updated the list of current and planned new {sup 99}Mo/{sup 99m}Tc irradiation and processing projects. The modelling results incorporate revisions to production start/end dates, potential additional projects, and impacts of converting to the use of low-enriched uranium (LEU) targets on {sup 99}Mo/{sup 99m}Tc capacity and production. The supply forecast horizon (2015 to 2020) has been chosen to reflect upcoming, important changes in global production capacity

  6. Nanocluster metal films as thermoelectric material for radioisotope mini battery unit

    Science.gov (United States)

    Borisyuk, P. V.; Krasavin, A. V.; Tkalya, E. V.; Lebedinskii, Yu. Yu.; Vasiliev, O. S.; Yakovlev, V. P.; Kozlova, T. I.; Fetisov, V. V.

    2016-10-01

    The paper is devoted to studying the thermoelectric and structural properties of films based on metal nanoclusters (Au, Pd, Pt). The experimental results of the study of single nanoclusters' tunneling conductance obtained with scanning tunneling spectroscopy are presented. The obtained data allowed us to evaluate the thermoelectric power of thin film consisting of densely packed individual nanoclusters. It is shown that such thin films can operate as highly efficient thermoelectric materials. A scheme of miniature thermoelectric radioisotope power source based on the thorium-228 isotope is proposed. The efficiency of the radioisotope battery using thermoelectric converters based on nanocluster metal films is shown to reach values up to 1.3%. The estimated characteristics of the device are comparable with the parameters of up-to-date radioisotope batteries based on nickel-63.

  7. The beta-decay of Al-22

    NARCIS (Netherlands)

    Achouri, NL; Santos, FDO; Lewitowicz, M; Blank, B; Aysto, J; Canchel, G; Czajkowski, S; Dendooven, P; Emsallem, A; Giovinazzo, J; Guillet, N; Jokinen, A; Larid, AM; Longour, C; Perajarvi, K; Smirnova, N; Stanoiu, M

    2006-01-01

    In an experiment performed at the LISE3 facility of GANIL, we studied the decay of Al-22 produced by the fragmentation of a Ar-36 primary beam. A beta-decay half-life of T-1/2 = 91.1 +/- 0.5ms was measured. The beta-delayed one- and two-proton emission as well as beta-alpha and beta-delayed gamma-de

  8. Effective Majorana neutrino decay

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Lucia [Instituto de Fisica, Facultad de Ingenieria,Universidad de la Republica, Montevideo (Uruguay); Romero, Ismael; Peressutti, Javier; Sampayo, Oscar A. [Universidad Nacional de Mar del Plata, Departamento de Fisica, Instituto de Investigaciones Fisicas de Mar del Plata (IFIMAR) CONICET, UNMDP, Mar del Plata (Argentina)

    2016-08-15

    We study the decay of heavy sterile Majorana neutrinos according to the interactions obtained from an effective general theory. We describe the two- and three-body decays for a wide range of neutrino masses. The results obtained and presented in this work could be useful for the study of the production and detection of these particles in a variety of high energy physics experiments and astrophysical observations. We show in different figures the dominant branching ratios and the total decay width. (orig.)

  9. Visualization of Uptake of Mineral Elements and the Dynamics of Photosynthates in Arabidopsis by a Newly Developed Real-Time Radioisotope Imaging System (RRIS).

    Science.gov (United States)

    Sugita, Ryohei; Kobayashi, Natsuko I; Hirose, Atsushi; Saito, Takayuki; Iwata, Ren; Tanoi, Keitaro; Nakanishi, Tomoko M

    2016-04-01

    Minerals and photosynthates are essential for many plant processes, but their imaging in live plants is difficult. We have developed a method for their live imaging in Arabidopsis using a real-time radioisotope imaging system. When each radioisotope,(22)Na,(28)Mg,(32)P-phosphate,(35)S-sulfate,(42)K,(45)Ca,(54)Mn and(137)Cs, was employed as an ion tracer, ion movement from root to shoot over 24 h was clearly observed. The movements of(22)Na,(42)K,(32)P,(35)S and(137)Cs were fast so that they spread to the tip of stems. In contrast, high accumulation of(28)Mg,(45)Ca and(54)Mn was found in the basal part of the main stem. Based on this time-course analysis, the velocity of ion movement in the main stem was calculated, and found to be fastest for S and K among the ions we tested in this study. Furthermore, application of a heat-girdling treatment allowed determination of individual ion movement via xylem flow alone, excluding phloem flow, within the main stem of 43-day-old Arabidopsis inflorescences. We also successfully developed a new system for visualizing photosynthates using labeled carbon dioxide,(14)CO2 Using this system, the switching of source/sink organs and phloem flow direction could be monitored in parts of whole shoots and over time. In roots,(14)C photosynthates accumulated intensively in the growing root tip area, 200-800 µm behind the meristem. These results show that this real-time radioisotope imaging system allows visualization of many nuclides over a long time-course and thus constitutes a powerful tool for the analysis of various physiological phenomena.

  10. Solid targets for production of radioisotopes with cyclotron; Blancos solidos para produccion de radioisotopos con ciclotron

    Energy Technology Data Exchange (ETDEWEB)

    Paredes G, L.; Balcazar G, M. [Instituto Nacional de Investigaciones Nucleares, Direccion de Investigacion Tecnologica, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1999-07-01

    The design of targets for production of radioisotopes and radiopharmaceuticals of cyclotron to medical applications requires a detailed analysis of several variables such as: cyclotron operation conditions, choice of used materials as target and their physicochemical characteristics, activity calculation, the yielding of each radioisotope by irradiation, the competition of nuclear reactions in function of the projectiles energy and the collision processes amongst others. The objective of this work is to determine the equations for the calculation for yielding of solid targets at the end of the proton irradiation. (Author)

  11. First measurement of radioisotopes by collinear laser spectroscopy at an ion-guide separator

    Energy Technology Data Exchange (ETDEWEB)

    Cooke, J.L.; Cochrane, E.C.A.; Evans, D.E.; Griffith, J.A.R.; Persson, J.R.; Richardson, D.S.; Tungate, G.; Zybert, L. [School of Physics and Space Research, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Billowes, J.; Campbell, P.; Cooper, T.G.; Grant, I.S.; Levins, J.M.G.; Pearson, M.R.; Wheeler, P.D. [Schuster Laboratory, University of Manchester, Manchester M13 9PL (United Kingdom); Dendooven, P.; Honkanen, A.; Huhta, M.; Oinonen, M.; Penttilae, H.; Aeystoe, J. [Accelerator Laboratory, University of Jyvaeskylae, PL 35, Jyvaeskylae SF - 403 51 (Finland)

    1997-11-01

    The first successful application of an ion-guide separator (IGISOL) for collinear laser spectroscopy of radioisotopes has achieved an efficiency comparable with the best obtained with catcher-ionizer facilities. The ion beam energy spread was determined to be less than 6 eV, allowing laser fluorescence resonance signals for the {sup 140,142,144}Ba radioisotopes to be detected with high resolution and sensitivity. Applications of this technique to measuring nuclear properties of refractory elements and short lived isomers promises to be particularly advantageous. (author). Letter-to-the-editor.

  12. Actual and future situations of the use of radioisotopes; Situacion actual y futura del empleo de radioisotopos

    Energy Technology Data Exchange (ETDEWEB)

    Paredes G, L.C. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2005-07-01

    It is anticipated to medium term, an increase in the demand of the radioisotopes for medicine, industry and research, as well as the application of new radioisotopes derived from the development of new radiopharmaceuticals products for diagnosis and therapy applications. The personal and clinical dosimetry will have to be prepared for the new challenges. (Author)

  13. Pyrolysis of Animal Bones with Vitamin B12: A Facile Route to Efficient Transition Metal-Nitrogen-Carbon (TM-N-C) Electrocatalysts for Oxygen Reduction.

    Science.gov (United States)

    Dou, Meiling; He, Duanpeng; Shao, Wenhao; Liu, Haijing; Wang, Feng; Dai, Liming

    2016-02-24

    By pyrolyzing cattle bones, hierarchical porous carbon (HPC) networks with a high surface area (2520 m(2)  g(-1) ) and connected pores were prepared at a low cost and large scale. Subsequent co-pyrolysis of HPC with vitamin B12 resulted in the formation of three-dimensional (3D) hierarchically structured porous cobalt-nitrogen-carbon (Co-N-HPC) electrocatalysts with a surface area as high as 859 m(2)  g(-1) as well as a higher oxygen reduction reaction (ORR) electrocatalytic activity, better operation stability, and higher tolerance to methanol than the commercial Pt/C catalyst in alkaline electrolyte.

  14. High efficiency 4H-SiC betavoltaic power sources using tritium radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Christopher; Portnoff, Samuel [Widetronix Corp., Ithaca, New York 14850 (United States); Spencer, M. G. [Department of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14850 (United States)

    2016-01-04

    Realization of an 18.6% efficient 4H-silicon carbide (4H-SiC) large area betavoltaic power source using the radioisotope tritium is reported. A 200 nm 4H-SiC P{sup +}N junction is used to collect high-energy electrons. The electron source is a titanium tritide (TiH{sup 3}{sub x}) foil, or an integrated titanium tritide region formed by the diffusion of tritium into titanium. The specific activity of the source is directly measured. Dark current measured under short circuit conditions was less than 6.1 pA/cm{sup 2}. Samples measured with an external tritium foil produced an open circuit voltage of 2.09 V, short circuit current of 75.47 nA/cm{sup 2}, fill factor of 0.86, and power efficiency of 18.6%. Samples measured with an integrated source produced power efficiencies of 12%. Simulations were done to determine the beta spectrum (modified by self absorption) exiting the source and the electron hole pair generation function in the 4H-SiC. The electron-hole pair generation function in 4H-SiC was modeled as a Gaussian distribution, and a closed form solution of the continuity equation was used to analyze the cell performance. The effective surface recombination velocity in our samples was found to be 10{sup 5}–10{sup 6 }cm/s. Our analysis demonstrated that the surface recombination dominates the performance of a tritium betavoltaic device but that using a thin P{sup +}N junction structure can mitigate some of the negative effects.

  15. Status update of a free-piston Stirling convertor for radioisotope space power systems

    Science.gov (United States)

    White, Maurice; Qiu, Songgang; Augenblick, Jack; Peterson, Allen; Faultersack, Frank

    2001-02-01

    Free-piston Stirling engines offer a relatively mature technology that is well-suited for advanced, high-efficiency radioisotope space power systems. This paper updates results from a combination of DOE and NASA contracts with Stirling Technology Company (STC). These contracts have demonstrated STC's Stirling convertor technology in a configuration and power level representative of a space power system. Based on demonstrated performance, long-life maintenance-free technology heritage, and success with aggressively imposed vibration testing. DOE has awarded system integration contracts to Boeing, Lockheed Martin and Teledyne Energy Systems. The objectives of these competitive Phase I contracts are to develop complete spacecraft power system conceptual designs based on the STC Stirling convertor, and to plan subsequent phases for two launches. Performance results for the DOE 55-W(e) Technology Demonstration Convertors (TDC's) have met original projections. Although the TDC's were intended only for technology demonstration, they have achieved very aggressive efficiency goals, demonstrated convertor-induced vibration levels below the Jet Propulsion Laboratory (JPL) specifications, passed a simulated launch load vibration test at 0.2 g2/Hz (12.3 g rms), and met EMI/EMC goals for most contemplated missions. No consideration for EMI reduction was included in the TDC design. Minor changes are underway to reduce EMI levels, with a goal of meeting specifications for missions such as Solar Probe with highly sensitive instrumentation. The long-term objective for DOE is to develop a power system with a system efficiency exceeding 20% that can function with a high degree of reliability for 10 years and longer on deep space missions. .

  16. Dose calibrator linearity test: {sup 99m}Tc versus {sup 18}F radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Willegaignon, Jose; Coura-Filho, George Barberio; Garcez, Alexandre Teles, E-mail: willegaignon@hotmail.com [Instituto do Cancer do Estado de Sao Paulo Octavio Frias de Oliveira (ICESP), Sao Paulo, SP (Brazil); Sapienza, Marcelo Tatit; Buchpiguel, Carlos Alberto [Universidade de Sao Paulo (FM/USP), Sao Paulo, SP (Brazil). Fac. de Medicina; Alves, Carlos Eduardo Gonzalez Ribeiro; Cardona, Marissa Anabel Rivera; Gutterres, Ricardo Fraga [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)

    2015-01-15

    Objective: the present study was aimed at evaluating the viability of replacing {sup 18}F with {sup 99m}Tc in dose calibrator linearity testing. Materials and methods: the test was performed with sources of {sup 99m}Tc (62 GBq) and {sup 18}F (12 GBq) whose activities were measured up to values lower than 1 MBq. Ratios and deviations between experimental and theoretical {sup 99m}Tc and {sup 18}F sources activities were calculated and subsequently compared. Results: mean deviations between experimental and theoretical {sup 99m}Tc and {sup 18}F sources activities were 0.56 (± 1.79)% and 0.92 (± 1.19)%, respectively. The mean ratio between activities indicated by the device for the {sup 99m}Tc source as measured with the equipment precalibrated to measure {sup 99m}Tc and {sup 18}F was 3.42 (± 0.06), and for the {sup 18}F source this ratio was 3.39 (± 0.05), values considered constant over the measurement time. Conclusion: the results of the linearity test using {sup 99m}Tc were compatible with those obtained with the {sup 18}F source, indicating the viability of utilizing both radioisotopes in dose calibrator linearity testing. Such information in association with the high potential of radiation exposure and costs involved in {sup 18}F acquisition suggest {sup 99m}Tc as the element of choice to perform dose calibrator linearity tests in centers that use {sup 18}F, without any detriment to the procedure as well as to the quality of the nuclear medicine service. (author)

  17. ELUCIDATION OF HYDRODESULFURIZATION AND HYDROGENATION MECHANISMS USING RADIOISOTOPE TRACER METHODS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To meet the specification of sulfur and aromatic contents in diesel fuel, it is necessary for refiners to develop a new catalyst with high activity of hydrodesulfurization and hydrogenation. In the present study, the properties of noble metal catalysts for hydrodesulfurization and hydrogenation in the presence of sulfur compounds have been investigated. The hydrogenation activity of phenanthrene (PHE) on single noble metal and double noble metal catalysts—Pt/Al2O3, Pd/Al2O3 and Pd-Pt/Al2O3 in the presence of dibenzothiophene (DBT) was perforrned in a fixed bed flow reactor. The Pt based catalysts revealed the similar HDS activities and higher HYD activity compared with convertional Mo based ca-talysts. The maximum activity was obtained around 320 ℃ for both catalyst types. The Pt based catalysts produced perhydrophenanthrene as a major product at the maximum activity in the hydrogenation of PHE while the Mo based catalysts produced octahydrophenanthrene.   A  35S radioisotope pulse tracer method (35S RPTM) was used to estimate the behavior of sulfur on the working catalysts and to clarity the differences between Pt and Mo based catalysts. Very little amount of labile sulfur was accumulated on the Pt and Pd catalysts in the HDS of [35S]DBT (PtS0.25 or PdS0.25). This indicates that the mechanism of DBT HDS on noble metal catalysts is significantly different from that on conventional Mo based catalysts where Mo is present as MoS2 less than 60% of which can be labile in the case of Co-Mo/Al2O3.   Another Ru-Cs/Al2O3 catalysts were also prepared and the behavior of sulfur on the working catalyst was compared with those of Mo based catalysts and Pt and Pd catalysts. The values of labile sulfur in the HDS reaction for Ru-Cs catalysts approximately correspond to RuS0.5-0.74. These amounts of labile sulfur are much higher than those for Pt and Pd catalysts. The result suggests that the oxidation state of Ru species is present between the oxidation states

  18. Brachytherapy on restenosis. {sup 32}P radioisotope in animal model

    Energy Technology Data Exchange (ETDEWEB)

    Bergoc, R.; Rivera, E.; Cocca, C.; Martin, G.; Cricco, G. [Buenos Aires Univ. (Argentina). School of Pharmacy and Biochemistry; Croci, M.; Guzman, L.

    2000-05-01

    Despite a notorious decline in age-adjusted death rates for cardiovascular pathologies, coronary artery disease still remains as the main cause of mortality above the age of 40 in men and 60 in women. More than 25% of death in persons over the age of 35 are due to coronary disease. In about 50% of men and 30% of women, the first manifestation of the disease is an acute myocardial infarction and 10% a sudden cardiac death. In Argentina it is estimated that in 1998 about 100.000-115.000 people suffered as first manifestation of coronary illness a myocardial acute infarct. Angioplasty has an important and well established site in the treatment of the coronary illness and restenosis represents the principal complication of this method for myocardial re-vascularization. About a 35-40% of treated arteries present restenosis within the first six month the intervention with the concomitant need of re-interventions, re-hospitalizations, by-pass surgery, work discontinuity and the high cost for the health system. A number of drugs were tested as anti-restenosis: anticoagulants, aspirin, antispasmodics and lipid-lowering agents but none was clearly efficient; also, experimental studies in which intravascular irradiation with different source types and energies, radiation doses and doses rate to prevent restenosis was utilized; however, there is no consensus in many aspects of this intravascular brachytherapy. The first step in this work was to induce the experimental model in rabbits. Afterwards, by means of the balloon methodology and stent implantation, brachytherapy experiments were carried out to evaluate the biological effect on different layers of arteries, with different Doses using a beta particle emitting radioisotope ({sup 32}P). The arteriosclerotic lesions were induced in New Zealand rabbits through the administration of a diet with high cholesterol content. Angioplastic interventions on femoral arteries were done with balloon methodology and controlled by

  19. Rare Semileptonic Charm Decays

    CERN Document Server

    de Boer, Stefan

    2015-01-01

    An analysis of charm mesons decaying semileptonically via Flavor Changing Neutral Currents is presented. We calculate the Wilson coefficients within the Standard Model. A window in the decay distribution, where physics beyond the Standard Model could be measured is identified. Exemplary, we study effects of leptoquark models.

  20. Double beta decay experiments

    CERN Document Server

    Barabash, A S

    2011-01-01

    The present status of double beta decay experiments is reviewed. The results of the most sensitive experiments are discussed. Proposals for future double beta decay experiments with a sensitivity to the $$ at the level of (0.01--0.1) eV are considered.

  1. Observation of semileptonic decay

    Science.gov (United States)

    Albrecht, H.; Cronström, H. I.; Ehrlichmann, H.; Hamacher, T.; Hofmann, R. P.; Kirchhoff, T.; Nau, A.; Nowak, S.; Reidenbach, M.; Reiner, R.; Schröder, H.; Schulz, H. D.; Walter, M.; Wurth, R.; Appuhn, R. D.; Hast, C.; Kolanoski, H.; Lange, A.; Lindner, A.; Mankel, R.; Schieber, M.; Siegmund, T.; Spaan, B.; Thurn, H.; Töpfer, D.; Walther, A.; Wegener, D.; Paulini, M.; Reim, K.; Wegener, H.; Mundt, R.; Oest, T.; Schmidt-Parzefall, W.; Funk, W.; Stiewe, J.; Werner, S.; Ehret, K.; Hölscher, A.; Hofmann, W.; Hüpper, A.; Khan, S.; Knöpfle, K. T.; Spengler, J.; Britton, D. I.; Charlesworth, C. E. K.; Edwards, K. W.; Hyatt, E. R. F.; Kapitza, H.; Krieger, P.; Macfarlane, D. B.; Patel, P. M.; Prentice, J. D.; Saull, P. R. B.; Seidel, S. C.; Tzamariudaki, K.; van de Water, R. G.; Yoon, T.-S.; Reβing, D.; Schmidtler, M.; Schneider, M.; Schubert, K. R.; Strahl, K.; Waldi, R.; Weseler, S.; Kernel, G.; Križan, P.; Križnič, E.; Podobnik, T.; Živko, T.; Jönsson, L.; Balagura, V.; Belyaev, I.; Danilov, M.; Droutskoy, A.; Golutvin, A.; Gorelov, I.; Kostina, G.; Lubimov, V.; Murat, P.; Pakhlov, P.; Ratnikov, F.; Semenov, S.; Shibaev, V.; Soloshenko, V.; Tichomirov, I.; Zaitsev, Yu.; Argus Collaboration

    1993-04-01

    Observation of the semileptonic decay of the charmed baryon ? in the decay channel ? has been made using the ARGUS detector at the e+e- storage ring DORIS II at DESY. The cross section times branching ratio was found to be ?.

  2. The study on the adaptation for regulation - the permission of a radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byoung Il; Choi, Won Seok; Jung, Yong Moon [Gallup Korea, Seoul (Korea, Republic of)

    2003-08-15

    The restriction -the permission of a radioisotope keeps satisfaction with almost parts for example, awareness, observance and so on. Moreover two concepts are considered fully -too strict about certain specific control rules and needed more discriminated application standards to each organization related to KINS, it's preserved and controlled properly even if the penalties are downsized.

  3. [Radioisotope thermoelectric generators and ancillary activities]. Monthly technical progress report, 1 April--28 April 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    Tehnical progress achieved during this period on radioisotope thermoelectric generators is described under the following tasks: engineering support, safety analysis, qualified unicouple fabrication, ETG fabrication/assembly/test, RTG shipping/launch support, design/review/mission applications, and project management/quality assurance/reliability.

  4. The radioisotope complex project “RIC-80” at the Petersburg Nuclear Physics Institute

    Energy Technology Data Exchange (ETDEWEB)

    Panteleev, V. N., E-mail: vnp@pnpi.spb.ru; Barzakh, A. E.; Batist, L. Kh.; Fedorov, D. V.; Ivanov, V. S.; Moroz, F. V.; Molkanov, P. L.; Orlov, S. Yu.; Volkov, Yu. M. [NRC “Kurchatov Institute” PNPI, 188300 Gatchina (Russian Federation)

    2015-12-15

    The high current cyclotron C-80 capable of producing 40-80 MeV proton beams with a current of up to 200 μA has been constructed at Petersburg Nuclear Physics Institute. One of the main goals of the C-80 is the production of a wide spectrum of medical radionuclides for diagnostics and therapy. The project development of the radioisotope complex RIC-80 (radioisotopes at the cyclotron C-80) at the beam of C-80 has been completed. The RIC-80 complex is briefly discussed in this paper. The combination of the mass-separator with the target-ion source device, available at one of the new target stations for on-line or semi on-line production of a high purity separated radioisotopes, is explored in greater detail. The results of target and ion source tests for a mass-separator method for the production of high purity radioisotopes {sup 82}Sr and {sup 223,224}Ra are also presented.

  5. Summary, the 20th quality control survey for radioisotopes in vitro tests in Japan, 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-11-01

    For advancement of radioisotope in vitro tests such as radioimmunoassay and immunoradiometric assay, the Subcommittee for Radioisotope in vitro Test in Medical and Pharmaceutical Committee of Japan Radioisotope Association has conducted the yearly quality control survey for the test facilities in Japan since 1978. This is the summary of the 20th survey in 1998 where non-radioisotope tests like enzyme-immunoassay were involved as well. The survey was done for 143 facilities: 20 national and public university hospitals, 18 private university hospitals, 8 national hospitals, 13 public hospitals, 21 private hospitals, 41 hygienic laboratories and 22 manufacturers of reagents. Facilities examined intra- and between day-reproducibility, freeze-thaw effect and time change of the measured values on the same samples. Assays were for: growth hormone (h), somatomedin C, follicle stimulating h, luteinizing h, prolactin, thyroid stimulating h, triiodothyronines, thyroxines, thyroxine binding protein, calcitonin, insulin, C-peptide, glucagons, gastrin, testosterones, estradiol, progesterone, gonadotropin, 17{alpha}-hydroxyprogesterone, aldosterone, cortisol, dehydroepiandorosterone sulfate, renin, IgE, digoxin, {alpha}-fetoprotein, carcinoembryonic antigen, tissue polypeptide antigen, CA (125, 19-9 and 15-3), prostatic acid phosphatase, prostate specific antigen, {beta}2-microglobulin, ferritin, and neuron specific enolase. There was no great difference between this and last survey results although tendency of improvement was recognized. There were problems to be solved from the standpoint of clinical practice. (K.H.)

  6. Radioisotopic methods for the study of bone sarcoma and soft tissue neoplasms

    Energy Technology Data Exchange (ETDEWEB)

    Gongora, R.

    1988-01-01

    Radioisotopic methods are widely applied to investigations of bone sarcoma and soft tissue neoplasms. We have at our disposal molecules with osseous, tumoral or vascular tropism. Their use, as single agents or combination, is helpful in positive and differential diagnosis and provides nosological informations. They are also useful in treatment monitoring and in long-term follow-up.

  7. First measurement of radioisotopes by collinear laser spectroscopy at an ion-guide separator

    NARCIS (Netherlands)

    Cooke, JL; Billowes, J; Campbell, P; Cochrane, ECA; Cooper, TG; Dendooven, P; Evans, DE; Griffith, JAR; Grant, IS; Honkanen, A; Huhta, M; Levins, JMG; Oinonen, M; Pearson, MR; Penttila, H; Persson, B.L.; Richardson, DS; Tungate, G; Wheeler, PD; Zybert, L; Aysto, J

    1997-01-01

    The first successful application of an ion-guide separator (IGISOL) for collinear laser spectroscopy of radioisotopes has achieved an efficiency comparable with the best obtained with catcher-ionizer facilities. The ion beam energy spread was determined to be less than 6 eV, allowing laser fluoresce

  8. The use of radioisotopes in medicine and medical research, Australia 1947-73

    Energy Technology Data Exchange (ETDEWEB)

    Korszniak, N

    1994-12-01

    On March 31, 1994, an article appeared in the Melbourne Age claiming that after the Second World War `hundreds of people were injected with radioactive materials in medical experiments that continued in Australian hospitals until the 1960s. Similar reports subsequently appeared in other newspapers and on the television and radio news. The archival records held at the Australian Radiation Laboratory (ARL) pertaining to the medical uses of radioisotopes during the period 1947-1973 have been examined to ascertain the nature of radioisotope use, and in the case of experimental procedures, any ethical considerations. The material examined indicates that the distribution and medical use of radioactive isotopes was stringently controlled by the Radio-isotope Standing Committee (established by the National Health and Medical Research Council (NHMRC) in 1947 to oversee this area) until its disbandment in 1973, when the responsibility for regulation of the use of radioactive isotopes for medical purposes in Australia passed to the Therapeutic Goods Administration. A database, showing details of over 500 radioisotope use in Australia between 1947-1973 is given in Appendix III . (author) refs., tabs.

  9. Planetary Protection Concerns During Pre-Launch Radioisotope Power System Final Integration Activities

    Science.gov (United States)

    Chen, Fei; McKay, Terri; Spry, James A.; Colozza, Anthony J.; DiStefano, Salvador

    2012-01-01

    The Advanced Stirling Radioisotope Generator (ASRG) is a next-generation radioisotope-based power system that is currently being developed as an alternative to the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG). Power sources such as these may be needed for proposed missions to solar system planets and bodies that have challenging Planetary Protection (PP) requirements (e.g. Mars, Europa, Enceladus) that may support NASA s search for life, remnants of past life, and the precursors of life. One concern is that the heat from the ASRG could potentially create a region in which liquid water may occur. As advised by the NASA Planetary Protection Officer, when deploying an ASRG to Mars, the current COSPAR/NASA PP policy should be followed for Category IVc mission. Thus, sterilization processing of the ASRG to achieve bioburden reduction would be essential to meet the Planetary Protection requirements. Due to thermal constraints and associated low temperature limits of elements of the ASRG, vapor hydrogen peroxide (VHP) was suggested as a candidate alternative sterilization process to complement dry heat microbial reduction (DHMR) for the assembled ASRG. The following proposed sterilization plan for the ASRG anticipates a mission Category IVc level of cleanliness. This plan provides a scenario in which VHP is used as the final sterilization process. Keywords: Advanced Stirling Radioisotope Generator (ASRG), Planetary Protection (PP), Vapor hydrogen peroxide (VHP) sterilization.

  10. 78 FR 15009 - Consideration of Withdrawal From Commercial Production and Distribution of the Radioisotope...

    Science.gov (United States)

    2013-03-08

    ... Consideration of Withdrawal From Commercial Production and Distribution of the Radioisotope Germanium-68 AGENCY... comment and information from the public to assist in its consideration of DOE withdrawal from the... summary, DOE's evaluation will include consideration of: a demonstrable private capability to produce...

  11. A novel method based on selective laser sintering for preparing high-performance carbon fibres/polyamide12/epoxy ternary composites

    Science.gov (United States)

    Zhu, Wei; Yan, Chunze; Shi, Yunsong; Wen, Shifeng; Liu, Jie; Wei, Qingsong; Shi, Yusheng

    2016-01-01

    A novel method based on selective laser sintering (SLS) process is proposed for the first time to prepare complex and high-performance carbon fibres/polyamide12/epoxy (CF/PA12/EP) ternary composites. The procedures are briefly described as follows: prepare polyamide12 (PA12) coated carbon fibre (CF) composite powder; build porous green parts by SLS; infiltrate the green parts with high-performance thermosetting epoxy (EP) resin; and finally cure the resin at high temperature. The obtained composites are a ternary composite system consisting of the matrix of novolac EP resin, the reinforcement of CFs and the transition thin layer of PA12 with a thickness of 595 nm. The SEM images and micro-CT analysis prove that the ternary system is a three-dimensional co-continuous structure and the reinforcement of CFs are well dispersed in the matrix of EP with the volume fraction of 31%. Mechanical tests show that the composites fabricated by this method yield an ultimate tensile strength of 101.03 MPa and a flexural strength of 153.43 MPa, which are higher than those of most of the previously reported SLS materials. Therefore, the process proposed in this paper shows great potential for manufacturing complex, lightweight and high-performance CF reinforced composite components in aerospace, automotive industries and other areas. PMID:27650254

  12. A novel method based on selective laser sintering for preparing high-performance carbon fibres/polyamide12/epoxy ternary composites.

    Science.gov (United States)

    Zhu, Wei; Yan, Chunze; Shi, Yunsong; Wen, Shifeng; Liu, Jie; Wei, Qingsong; Shi, Yusheng

    2016-09-21

    A novel method based on selective laser sintering (SLS) process is proposed for the first time to prepare complex and high-performance carbon fibres/polyamide12/epoxy (CF/PA12/EP) ternary composites. The procedures are briefly described as follows: prepare polyamide12 (PA12) coated carbon fibre (CF) composite powder; build porous green parts by SLS; infiltrate the green parts with high-performance thermosetting epoxy (EP) resin; and finally cure the resin at high temperature. The obtained composites are a ternary composite system consisting of the matrix of novolac EP resin, the reinforcement of CFs and the transition thin layer of PA12 with a thickness of 595 nm. The SEM images and micro-CT analysis prove that the ternary system is a three-dimensional co-continuous structure and the reinforcement of CFs are well dispersed in the matrix of EP with the volume fraction of 31%. Mechanical tests show that the composites fabricated by this method yield an ultimate tensile strength of 101.03 MPa and a flexural strength of 153.43 MPa, which are higher than those of most of the previously reported SLS materials. Therefore, the process proposed in this paper shows great potential for manufacturing complex, lightweight and high-performance CF reinforced composite components in aerospace, automotive industries and other areas.

  13. A novel method based on selective laser sintering for preparing high-performance carbon fibres/polyamide12/epoxy ternary composites

    Science.gov (United States)

    Zhu, Wei; Yan, Chunze; Shi, Yunsong; Wen, Shifeng; Liu, Jie; Wei, Qingsong; Shi, Yusheng

    2016-09-01

    A novel method based on selective laser sintering (SLS) process is proposed for the first time to prepare complex and high-performance carbon fibres/polyamide12/epoxy (CF/PA12/EP) ternary composites. The procedures are briefly described as follows: prepare polyamide12 (PA12) coated carbon fibre (CF) composite powder; build porous green parts by SLS; infiltrate the green parts with high-performance thermosetting epoxy (EP) resin; and finally cure the resin at high temperature. The obtained composites are a ternary composite system consisting of the matrix of novolac EP resin, the reinforcement of CFs and the transition thin layer of PA12 with a thickness of 595 nm. The SEM images and micro-CT analysis prove that the ternary system is a three-dimensional co-continuous structure and the reinforcement of CFs are well dispersed in the matrix of EP with the volume fraction of 31%. Mechanical tests show that the composites fabricated by this method yield an ultimate tensile strength of 101.03 MPa and a flexural strength of 153.43 MPa, which are higher than those of most of the previously reported SLS materials. Therefore, the process proposed in this paper shows great potential for manufacturing complex, lightweight and high-performance CF reinforced composite components in aerospace, automotive industries and other areas.

  14. A multi-functional electronic program for the management of radioisotopes.

    Science.gov (United States)

    Ritchot, Nathalie; Santary, William

    2008-05-01

    Everyone will agree that specialized computer programs have done away with the many tedious tasks associated with manually keeping track of radioisotopes. Enhanced electronic programs have virtually cut the time of managing radioisotopes. Agriculture and Agri-Food, Canada's (AAFC) program for the management of radioisotopes, is somewhat different from most electronic programs. It is divided into three levels of management that are dependent on the roles that a user might have when applying the application. These roles include the Departmental Radiation Safety Officer (DRSO), Radiation Safety Officer (RSO), and authorized user, which meets the requirements of the Canadian Nuclear Safety Commission. The DRSO and authorized AAFC Radiation Safety Committee members have access to the first level of management. This is the highest level of control, and only the DRSO has permission to add a nuclear substance to the system with the approval of the Canadian Nuclear Safety Commission (CNSC). This level of management is also responsible for adding authorized users, locations, and managing the Internal Use Permits. The second level of management is for site-specific RSOs. They have access to all information regarding their center of activity, but they cannot change Internal Use Permit data. The RSOs can reset passwords, authorize new users, control the maximum activity limit, etc., but are limited to viewing only the information that relates to their internal use permit. However, they retain significant control within the permit. The third and last level of management is for authorized users who can access the radioisotope order-distribution-disposal section, waste or storage containers creation file, and leak/wipe test procedures. As in the case of the DRSO and RSO, they also have access to all reports and inventories for their center of activity but they cannot change Internal Use Permit or inventories data. This program has proven to be a valuable tool for scientific staff

  15. Search for W-prime boson decaying to electron-neutrino pairs in p anti-p collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Abulencia, A.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M.G.; Ambrose, D.; Amerio, S.; Amidei, D.; Anastassov, A.; Anikeev, K.; Annovi, A.; /Taiwan, Inst. Phys.

    2006-11-01

    The authors present the results of a search for W{prime} boson decaying to electron-neutrino pairs in p{bar p} collisions at a center-of-mass energy of 1.96 TeV, using a data sample corresponding to 205 pb{sup -1} of integrated luminosity collected by the CDF II detector at Fermilab. They observe no evidence for this decay mode and set limits on the production cross section times branching fraction, assuming the neutrinos from W{prime} boson decays to be light. If they assume the manifest left-right symmetric model, they exclude a W{prime} boson with mass less than 788 GeV/c{sup 2} at the 95% confidence level.

  16. Search for Resonant Pair Production of long-lived particles decaying to b anti-b in p anti-p collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /York U., Canada /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.

    2009-06-01

    We report on a first search for production of Higgs bosons decaying into neutral long-lived particles (NLLP) which each decay to a b{bar b} pair, using 3.6 fb{sup -1} of data recorded with the D0 detector at the Fermilab Tevatron collider. We search for pairs of displaced vertices in the tracking detector at radii in the range 1.6-20 cm from the beam axis. No significant excess is observed above background, and upper limits are set on the production rate in a hidden-valley benchmark model for a range of Higgs boson masses and NLLP masses and lifetimes.

  17. Exotic decay in cerium isotopes

    Indian Academy of Sciences (India)

    K P Santhosh; Antony Joseph

    2002-04-01

    Half life for the emission of exotic clusters like 8Be, 12C, 16O, 20Ne, 24Mg and 28Si are computed taking Coulomb and proximity potentials as interacting barrier and many of these are found well within the present upper limit of measurement. These results lie very close to those values reported by Shanmugam et al using their cubic plus Yukawa plus exponential model (CYEM). It is found that 12C and 16O emissions from 116Ce and 16O from 118Ce are most favorable for measurement (1/2 < 1010 s). Lowest half life time for 16O emission from 116Ce stress the role of doubly magic 100Sn daughter in exotic decay. Geiger–Nuttall plots were studied for different clusters and are found to be linear. Inclusion of proximity potential will not produce much deviation to linear nature of Geiger–Nuttall plots. It is observed that neutron excess in the parent nuclei slow down the exotic decay process. These findings support the earlier observations of Gupta and collaborators using their preformed cluster model (PCM).

  18. Axions from wall decay

    Energy Technology Data Exchange (ETDEWEB)

    Chang, S; Hagmann, C; Sikivie, P

    2001-01-08

    The authors discuss the decay of axion walls bounded by strings and present numerical simulations of the decay process. In these simulations, the decay happens immediately, in a time scale of order the light travel time, and the average energy of the radiated axions is {approx_equal} 7m{sub a} for v{sub a}/m{sub a} {approx_equal} 500. is found to increase approximately linearly with ln(v{sub a}/m{sub a}). Extrapolation of this behavior yields {approx_equal} 60 m{sub a} in axion models of interest.

  19. Rare decays at LHCb

    CERN Document Server

    Lafferty, George

    2015-01-01

    We review recent results from the LHCb experiment on studies of particle decays that are forbidden or rare in the Standard Model. The studies include searches for lepton flavour violating decays of the $\\tau$ lepton and the $B$ and $D$ mesons, and of $B$ and $D$ meson decays that would be mediated by Majorana neutrinos. Results are also presented for the rare processes $B_s \\to \\mu^+\\mu^-$ and $B^0 \\to \\mu^+\\mu^-$, $D^0 \\to \\pi^+\\pi^-\\mu^+\\mu^-$, $b \\to s\\gamma$ transitions, and $B \\to K^{(*)}\\mu^+\\mu^-$.

  20. Weak decays and double beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Nicholson, H.W.

    1983-08-01

    Work to measure the ..sigma../sup +/ 0 degree differential cross section in the reaction K/sup -/p ..-->.. ..sigma../sup +/..pi../sup -/ at several incident K/sup -/ momenta between 600 and 800 MeV/c as well as the asymmetries in the decays of polarized ..sigma../sup +/'s into protons and neutral pions and of polarized ..sigma../sup -/'s into neutrons and negative pions in collaboration with experimenters from Yale, Brookhaven, and the University of Pittsburgh (Brookhaven experiment 702) has been completed. Data from this experiment is currently being analyzed at Yale. Work is currently underway to develop and construct an experiment to search for neutrinoless double beta decay in thin foils of Mo/sup 100/ in collaboration with experimenters from Lawrence Berkeley Laboratory. Development work on the solid state silicon detectors should be complete in the next six months and construction should e well underway within the next year.

  1. Non-leptonic decays of beauty decays

    CERN Document Server

    Bigi, Ikaros I; Shifman, M; Uraltsev, N; Vainshtein, A I

    1994-01-01

    "Anyone who keeps the ability to see beauty never grows old" (Franz Kafka). In the last few years considerable progress has been achieved in our understanding of the decays of heavy flavour hadrons. One can now calculate inclusive transition rates in QCD proper through an expansion in inverse powers of the heavy flavour quark mass without recourse to phenomenological assumptions. The non-perturbative contributions are treated systematically in this way; they are found to produce corrections of order a few percent in beauty decays, i.e. typically somewhat smaller than the perturbative corrections. One finds, among other things: (a) The lifetime of $B^-$ mesons is predicted to be longer than that of $B^0$ mesons by several percent. (b) The QCD prediction for the semileptonic branching ratio of $B$ mesons appears to exceed present experimental values.

  2. Advanced Stirling Radioisotope Generator (ASRG) Thermal Power Model in MATLAB

    Science.gov (United States)

    Wang, Xiao-Yen, J.

    2012-01-01

    This paper presents a one-dimensional steady-state mathematical thermal power model of the ASRG. It aims to provide a guideline of understanding how the ASRG works and what can change its performance. The thermal dynamics and energy balance of the generator is explained using the thermal circuit of the ASRG. The Stirling convertor performance map is used to represent the convertor. How the convertor performance map is coupled in the thermal circuit is explained. The ASRG performance characteristics under i) different sink temperatures and ii) over the years of mission (YOM) are predicted using the one-dimensional model. Two Stirling converter control strategies, i) fixing the hot-end of temperature of the convertor by adjusting piston amplitude and ii) fixing the piston amplitude, were tested in the model. Numerical results show that the first control strategy can result in a higher system efficiency than the second control strategy when the ambient gets warmer or the general-purpose heat source (GPHS) fuel load decays over the YOM. The ASRG performance data presented in this paper doesn't pertain to the ASRG flight unit. Some data of the ASRG engineering unit (EU) and flight unit that are available in public domain are used in this paper for the purpose of numerical studies.

  3. Spatial distribution of radioisotopes in the coast of Suez Gulf, southwestern Sinai and the impact of hot springs.

    Science.gov (United States)

    Ramadan, Kh A; Seddeek, M K; Elnimr, T; Sharshar, T; Badran, H M

    2011-06-01

    This work describes the concentrations of radioisotopes in soil, sediment, wild plants and groundwater in southwestern Sinai. The study area extends from Suez to Abu Rudies along the eastern part of the Suez Gulf. It included two hot springs: Ayun Musa and Hammam Faraoun. No dependence of ¹³⁷Cs concentrations on any of the measured sand characteristics was found, including calcium carbonate. The enrichment of ²²⁶Ra in Hammam Faraoun hot spring was the most prominent feature. The ²²⁶Ra concentration in hot springs of Ayun Musa and Hammam Faraoun were 68 and 2377 Bq kg⁻¹ for sediments, 3.5 and 54.0 Bq kg⁻¹ for wild plants and 205 and 1945 mBq l⁻¹ for the groundwater, respectively. In addition, ²²⁶Ra activity concentration in local sand in the area of Hammam Faraoun was ∼14 times that of Ayun Musa. On the other hand, the ²³²Th concentrations were comparable in the two hot springs, while ¹³⁷Cs concentrations were relatively higher in Ayun Musa. The characteristics and radioelements studies support possible suggestions that the waters in the two hot springs have different contributions of sea and groundwaters crossing different geological layers where the water-rock interaction takes place.

  4. Preparation and electrochemical performance of hyper-networked Li4Ti5O12/carbon hybrid nanofiber sheets for a battery-supercapacitor hybrid system

    Science.gov (United States)

    Choi, Hong Soo; Kim, TaeHoon; Im, Ji Hyuk; Park, Chong Rae

    2011-10-01

    Hyper-networked Li4Ti5O12/carbon hybrid nanofiber sheets that contain both a faradaically rechargeable battery-type component, namely Li4Ti5O12, and a non-faradaically rechargeable supercapacitor-type component, namely N-enriched carbon, are prepared by electrospinning and their dual function as a negative electrode of lithium-ion batteries (LIBs) and a capacitor is tested for a new class of hybrid energy storage (denoted BatCap). An aqueous solution composed of polyvinylpyrrolidone, lithium hydroxide, titanium(IV) bis(ammonium-lactato)dihydroxide and ammonium persulfate is electrospun to obtain hyper-networked nanofiber sheets. Next, the sheets are exposed to pyrrole monomer vapor to prepare the polypyrrole-coated nanofiber sheets (PPy-HNS). The hyper-networked Li4Ti5O12/N-enriched carbon hybrid nanofiber sheets (LTO/C-HNS) are then obtained by a stepwise heat treatment of the PPy-HNS. The LTO/C-HNS deliver a specific capacity of 135 mAh g - 1 at 4000 mA g - 1 as a negative electrode for LIBs. In addition, potentiodynamic experiments are performed using a full cell with activated carbon (AC) as the positive electrode and LTO/C-HNS as the negative electrode to estimate the capacitance properties. This new asymmetric electrode system exhibits a high energy density of 91 W kg - 1 and 22 W kg - 1 at power densities of 50 W kg - 1 and 4000 W kg - 1, respectively, which are superior to the values observed for the {AC} \\parallel {AC} symmetric electrode system.

  5. Decay ring design

    CERN Document Server

    Chancé, A; Bouquerel, E; Hancock, S; Jensen, E

    The study of the neutrino oscillation between its different flavours needs pureand very intense fluxes of high energy, well collimated neutrinos with a welldetermined energy spectrum. A dedicated machine seems to be necessarynowadays to reach the required flux. A new concept based on the β-decayof radioactive ions which were accelerated in an accelerator chain was thenproposed. After ion production, stripping, bunching and acceleration, the unstableions are then stored in a racetrack-shaped superconducting decay ring.Finally, the ions are accumulated in the decay ring until being lost. The incomingbeam is merged to the stored beam by using a specific RF system, whichwill be presented here.We propose here to study some aspects of the decay ring, such as its opticalproperties, its RF system or the management of the losses which occur in thering (mainly by decay or by collimation).

  6. Neutrinoless double beta decay

    Indian Academy of Sciences (India)

    Kai Zuber

    2012-10-01

    The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations as well as the current status of experiments are presented. Finally, an outlook towards the future, work on nuclear matrix elements and alternative processes is given.

  7. Inflaton decay in supergravity

    Energy Technology Data Exchange (ETDEWEB)

    Endo, M.; Takahashi, F. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Yanagida, T.T. [Tokyo Univ. (Japan). Dept. of Physics]|[Tokyo Univ. (Japan). Research Center for the Early Universe

    2007-06-15

    We discuss inflaton decay in supergravity, taking account of the gravitational effects. It is shown that, if the inflaton has a nonzero vacuum expectation value, it generically couples to any matter fields that appear in the superpotential at the tree level, and to any gauge sectors through anomalies in the supergravity. Through these processes, the inflaton generically decays into the supersymmetry breaking sector, producing many gravitinos. The inflaton also directly decays into a pair of the gravitinos. We derive constraints on both inflation models and supersymmetry breaking scenarios for avoiding overproduction of the gravitinos. Furthermore, the inflaton naturally decays into the visible sector via the top Yukawa coupling and SU(3){sub C} gauge interactions. (orig.)

  8. RARE KAON DECAYS.

    Energy Technology Data Exchange (ETDEWEB)

    LITTENBERG, L.

    2005-07-19

    Lepton flavor violation (LFV) experiments have probed sensitivities corresponding to mass scales of well over 100 TeV, making life difficult for models predicting accessible LFV in kaon decay and discouraging new dedicated experiments of this type.

  9. CLEO Results B Decays

    CERN Document Server

    Cassel, David G

    2001-01-01

    Measurements of many Standard Model constants are clouded by uncertainties in nonperturbative QCD parameters that relate measurable quantities to the underlying parton-level processes. Generally these QCD parameters have been obtained from model calculations with large uncertainties that are difficult to quantify. The CLEO Collaboration has taken a major step towards reducing these uncertainties in determining the CKM matrix elements Vcb and Vub using new measurements of the branching fraction and photon energy spectrum of B -> s gamma decays. This report includes: the new CLEO measurements of B -> s gamma decays, Vcb, and Vub; the first results from CLEO III data -- studies of B -> K pi, pi pi, and K Kbar decays; mention of some other recent CLEO B decay results; and plans for operating CESR and CLEO in the charm threshold region.

  10. A Search for supersymmetric Higgs bosons in the di-tau decay mode in p anti-p collisions at s**(1/2) = 1.8-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, D.; Affolder, Anthony A.; Albrow, M.G.; Ambrose, D.; Amidei, D.; Anikeev, K.; Antos, J.; Apollinari, G.; Arisawa, T.; Artikov, A.; Ashmanskas, W.; Azfar, F.; Azzi-Bacchetta, P.; Bacchetta, N.; Bachacou, H.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V.E.; Barnett, B.A.; Baroiant, S.; Barone, M.; /Taiwan, Inst. Phys. /Argonne, PHY /INFN,

    2005-06-01

    A search for direct production of Higgs bosons in the di-tau decay mode is performed with 86.3 {+-} 3.5 pb{sup -1} of data collected with the Collider Detector at Fermilab during the 1994-1995 data taking period of the Tevatron. We search for events where one tau decays to an electron plus neutrinos and the other tau decays hadronically. We perform a counting experiment and set limits on the cross section for supersymmetric Higgs boson production where tan {beta} is large and m{sub A} is small. For a benchmark parameter space point where m{sub A{sup 0}} = 100 GeV/c{sup 2} and tan {beta} = 50, we limit the production cross section multiplied by the branching ratio to be less than 77.9 pb at the 95% confidence level compared to theoretically predicted value of 11.0 pb. This is the first search for Higgs bosons decaying to tau pairs at a hadron collider.

  11. Laser assisted {alpha} decay

    Energy Technology Data Exchange (ETDEWEB)

    Castaneda Cortes, Hector Mauricio

    2012-02-01

    Excited or short-lived nuclei often decay by emitting alpha particles that are assumed to be preformed inside the nucleus and confined in the nuclear potential well. In this picture, {alpha} decay refers to the tunneling of the alpha particle through the potential barrier. In this thesis we investigate for the first time how strong laser fields can assist the tunneling of the alpha particle and thus influence the nuclear decay. Generally speaking, laser-assisted {alpha} decay can be described as laser-assisted tunneling of a quasistationary state, i.e, a slowly decaying state. Our theoretical treatment is developed starting from the complex trajectory formulation of the well-known strong-field approximation used to describe laser-induced ionization. We extend this formulation and develop a method to treat the decay of quasistationary states. The effect of both static and optical and X-ray monochromatic fields on the lifetimes and {alpha}-particle emission spectra are investigated for a number of {alpha}-emitting nuclei. We find that even at strong intensities, the laser-induced acceleration of the {alpha} decay is negligible, ranging from a relative modification in the decay rate of 10{sup -3} for static fields of electric field strengths of 10{sup 15} V/m, to 10{sup -8} for strong optical fields with intensities of 10{sup 22} W/cm{sup 2}, and to 10{sup -6} for strong X-ray fields with laser intensities around 10{sup 24} W/cm{sup 2}. However, the effect of the external field is visible in the spectrum of emitted alpha particles, leading in the case of optical fields even to rescattering phenomena for intensities approaching 6 x 10{sup 22} W/cm{sup 2}. The dynamics of the alpha particle in laser fields of intensities below the rescattering limit is investigated.

  12. Solar Neutrino Decay

    CERN Document Server

    Acker, A; Acker, Andy; Pakvasa, Sandip

    1994-01-01

    We re-examine the neutrino decay solution to the solar neutrino problem in light of the new data from Gallex II and Kamiokande III. We compare the experimental data with the solar models of Bahcall and Pinsonneault and Turck-Chieze and find that neutrino decay is ruled out as a solution to the solar neutrino problem at better than the 98\\% c.l. even when solar model uncertainties are taken into account.

  13. Open Flavor Strong Decays

    Science.gov (United States)

    García-Tecocoatzi, H.; Bijker, R.; Ferretti, J.; Galatà, G.; Santopinto, E.

    2016-10-01

    In this contribution, we discuss the results of a QM calculation of the open-flavor strong decays of **** light nucleon resonances. These are the results of a recent calculation, where we used a modified ^3P_0 model for the amplitudes and the U(7) algebraic model and the hypercentral quark model to predict the baryon spectrum. The decay amplitudes are compared with the existing experimental data.

  14. Streamer chamber: pion decay

    CERN Multimedia

    1992-01-01

    The real particles produced in the decay of a positive pion can be seen in this image from a streamer chamber. Streamer chambers consist of a gas chamber through which a strong pulsed electric field is passed, creating sparks as a charged particle passes through it. A magnetic field is added to cause the decay products to follow curved paths so that their charge and momentum can be measured.

  15. Aspects of B decays

    Energy Technology Data Exchange (ETDEWEB)

    Faller, Sven

    2011-03-04

    B-meson decays are a good probe for testing the flavour sector of the standard model of particle physics. The standard model describes at present all experimental data satisfactorily, although some ''tensions'' exist, i.e. two to three sigma deviations from the predictions, in particular in B decays. The arguments against the standard model are thus purely theoretical. These tensions between experimental data and theoretical predictions provide an extension of the standard model by new physics contributions. Within the flavour sector main theoretical uncertainties are related to the hadronic matrix elements. For exclusive semileptonic anti B {yields} D{sup (*)}l anti {nu} decays QCD sum rule techniques, which are suitable for studying hadronic matrix elements, however, with substantial, but estimable hadronic uncertainties, are used. The exploration of new physics effects in B-meson decays is done in an twofold way. In exclusive semileptonic anti B {yields} D{sup (*)}l anti {nu} decays the effect of additional right-handed vector as well as left- and right-handed scalar and tensor hadronic current structures in the decay rates and the form factors are studied at the non-recoil point. As a second approach one studied the non-leptonic B{sup 0}{sub s}{yields}J/{psi}{phi} and B{sup 0}{yields}J/{psi}K{sub S,L} decays discussing CP violating effects in the time-dependent decay amplitudes by considering new physics phase in the B{sup 0}- anti B{sup 0} mixing phase. (orig.)

  16. Gold-Catalyzed Ring Expansion of Alkynyl Heterocycles through 1,2-Migration of an Endocyclic Carbon-Heteroatom Bond.

    Science.gov (United States)

    Chen, Ming; Sun, Ning; Xu, Wei; Zhao, Jidong; Wang, Gaonan; Liu, Yuanhong

    2015-12-14

    A mild and efficient gold-catalyzed oxidative ring-expansion of a series of alkynyl heterocycles using pyridine-N-oxide as the oxidant has been developed, which affords highly valuable six- or seven-membered heterocycles with wide functional group toleration. The reaction consists of a regioselective oxidation and a chemoselective migration of an endocyclic carbon-heteroatom bond (favored over C-H migration) with the order of migratory aptitude for carbon-heteroatom bonds being C-S>C-N>C-O. In the absence of an oxidant, polycyclic products are readily constructed through a ring-expansion/Nazarov cyclization reaction sequence.

  17. Quarterly Report for LANL Activities: FY12-Q2 National Risk Assessment Partnership (NRAP): Industrial Carbon Capture Program

    Energy Technology Data Exchange (ETDEWEB)

    Pawar, Rajesh J. [Los Alamos National Laboratory

    2012-04-17

    This report summarizes progress of LANL activities related to the tasks performed under the LANL FWP FE102-002-FY10, National Risk Assessment Partnership (NRAP): Industrial Carbon Capture Program. This FWP is funded through the American Recovery and Reinvestment Act (ARRA). Overall, the NRAP activities are focused on understanding and evaluating risks associated with large-scale injection and long-term storage of CO{sub 2} in deep geological formations. One of the primary risks during large-scale injection is due to changes in geomechanical stresses to the storage reservoir, to the caprock/seals and to the wellbores. These changes may have the potential to cause CO{sub 2} and brine leakage and geochemical impacts to the groundwater systems. While the importance of these stresses is well recognized, there have been relatively few quantitative studies (laboratory, field or theoretical) of geomechanical processes in sequestration systems. In addition, there are no integrated studies that allow evaluation of risks to groundwater quality in the context of CO{sub 2} injection-induced stresses. The work performed under this project is focused on better understanding these effects. LANL approach will develop laboratory and computational tools to understand the impact of CO{sub 2}-induced mechanical stress by creating a geomechanical test bed using inputs from laboratory experiments, field data, and conceptual approaches. The Geomechanical Test Bed will be used for conducting sensitivity and scenario analyses of the impacts of CO{sub 2} injection. The specific types of questions will relate to fault stimulation and fracture inducing stress on caprock, changes in wellbore leakage due to evolution of stress in the reservoir and caprock, and the potential for induced seismicity. In addition, the Geomechanical Test Bed will be used to investigate the coupling of stress-induced leakage pathways with impacts on groundwater quality. LANL activities are performed under two tasks

  18. Acute toxicity of combined photon IMRT and carbon ion boost for intermediate-risk prostate cancer - Acute toxicity of 12C for PC

    Energy Technology Data Exchange (ETDEWEB)

    Nikoghosyan, Anna V.; Herfarth, Klaus; Didinger, Bernd; Muenter, Marc W.; Jensen, Alexandra D.; Debus, Juergen (Dept. of Radiation Oncology, Univ. of Heidelberg (Germany)), e-mail: a.nikoghosyan@med.uni-heidelberg.de; Schulz-Ertner, Daniela (Radiological Inst. (Medical Care Unit), Markus Hospital, Frankfurt/Main (Germany)); Jaekel, Oliver (Dept. of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ) Heidelberg (Germany); Heidelberg Ion Beam Therapy Centre of the Univ. Hospital Heidelberg (Germany)); Hoess, Angelika; Haberer, Thomas (Heidelberg Ion Beam Therapy Centre of the Univ. Hospital Heidelberg (Germany))

    2011-08-15

    Background. Carbon ion (12C) therapy in the treatment of prostate cancer (PC) might result in an improved outcome as compared to low linear energy transfer irradiation techniques. In this study, we present the first interim report of acute side effects of the first intermediate-risk PC patients treated at the GSI (Gesellschaft fuer Schwerionenforschung) and the Univ. of Heidelberg in an ongoing clinical phase I/II trial using combined photon intensity modulated radiation therapy (IMRT) and 12C carbon ion boost. Material and methods. Fourteen patients (planned accrual: 31 pts) have been treated within this trial so far. IMRT is prescribed to the median PTV at a dose of 30 x 2 Gy; 12C boost is applied to the prostate (GTV) at a dose of 6 x 3 GyE using raster scan technique. Safety margins added to the clinical target volume were determined individually for each patient based on five independent planning computed tomography (CT)-scans. Acute gastrointestinal (GI) and genitourinary (GU) toxicity was assessed and documented according to the CTCAE Version 3.0. Results. Radiotherapy was very well tolerated without any grade 3 or higher toxicity. Acute anal bleeding grade 2 was observed in 2/14 patients. Rectal tenesmus grade 1 was reported by three other patients. No further GI symptoms have been observed. Most common acute symptoms during radiotherapy were nocturia and dysuria CTC grade 1 and 2 (12/14). There was no severe acute GU toxicity. Conclusion. The combination of photon IMRT and carbon ion boost is feasible in patients with intermediate-risk PC. So far, the treatment has been well tolerated. Acute toxicity rates were in good accordance with data reported for high dose IMRT alone

  19. 40 CFR 600.510-12 - Calculation of average fuel economy and average carbon-related exhaust emissions.

    Science.gov (United States)

    2010-07-01

    ... fuel as determined in § 600.113-08(a) and (b); FEpet is the fuel economy while operated on petroleum... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Calculation of average fuel economy... ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND CARBON-RELATED EXHAUST EMISSIONS...

  20. CARBON-RICH PRESOLAR GRAINS FROM MASSIVE STARS: SUBSOLAR {sup 12}C/{sup 13}C AND {sup 14}N/{sup 15}N RATIOS AND THE MYSTERY OF {sup 15}N

    Energy Technology Data Exchange (ETDEWEB)

    Pignatari, M. [Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklos ut 15-17, H-1121 Budapest (Hungary); Zinner, E. [Laboratory for Space Sciences and Physics Department, Washington University, St. Louis, MO 63130 (United States); Hoppe, P. [Max Planck Institute for Chemistry, D-55128 Mainz (Germany); Jordan, C. J.; Gibson, B. K. [E.A. Milne Centre for Astrophysics, Dept of Physics and Mathematics, University of Hull, HU6 7RX (United Kingdom); Trappitsch, R. [Department of the Geophysical Sciences and Chicago Center for Cosmochemistry, Chicago, IL 60637 (United States); Herwig, F. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P5C2 (Canada); Fryer, C. [Computational Physics and Methods (CCS-2), LANL, Los Alamos, NM, 87545 (United States); Hirschi, R. [Keele University, Keele, Staffordshire ST5 5BG (United Kingdom); Timmes, F. X. [The Joint Institute for Nuclear Astrophysics, Notre Dame, IN 46556 (United States)

    2015-08-01

    Carbon-rich grains with isotopic anomalies compared to the Sun are found in primitive meteorites. They were made by stars, and carry the original stellar nucleosynthesis signature. Silicon carbide grains of Type X and C and low-density (LD) graphites condensed in the ejecta of core-collapse supernovae. We present a new set of models for the explosive He shell and compare them with the grains showing {sup 12}C/{sup 13}C and {sup 14}N/{sup 15}N ratios lower than solar. In the stellar progenitor H was ingested into the He shell and not fully destroyed before the explosion. Different explosion energies and H concentrations are considered. If the supernova shock hits the He-shell region with some H still present, the models can reproduce the C and N isotopic signatures in C-rich grains. Hot-CNO cycle isotopic signatures are obtained, including a large production of {sup 13}C and {sup 15}N. The short-lived radionuclides {sup 22}Na and {sup 26}Al are increased by orders of magnitude. The production of radiogenic {sup 22}Ne from the decay of {sup 22}Na in the He shell might solve the puzzle of the Ne-E(L) component in LD graphite grains. This scenario is attractive for the SiC grains of type AB with {sup 14}N/{sup 15}N ratios lower than solar, and provides an alternative solution for SiC grains originally classified as nova grains. Finally, this process may contribute to the production of {sup 14}N and {sup 15}N in the Galaxy, helping to produce the {sup 14}N/{sup 15}N ratio in the solar system.

  1. The Kpi and pipi S-wave from D decays

    CERN Document Server

    Reis, Alberto

    2009-01-01

    This paper is focused on two issues: the K\\pi spectrum near threshold - the kappa problem -, and the pi\\pi spectrum between 1.2 and 1.5 GeV/(c^2) -- the f_0(1370) problem. Both problems will be analysed from the perspective of the $D$ meson decays, with some additional information from $\\tau$ and B decays.

  2. Improved Limit on Direct α Decay of the Hoyle State

    DEFF Research Database (Denmark)

    Kirsebom, Oliver Sølund; Alcorta, M.; Borge, M.J.G.

    2012-01-01

    The current evaluation of the triple-α reaction rate assumes that the α decay of the 7.65 MeV, 0+ state in 12C, commonly known as the Hoyle state, proceeds sequentially via the ground state of 8Be. This assumption is challenged by the recent identification of two direct α-decay branches with a co...

  3. Impact of a CXCL12/CXCR4 Antagonist in Bleomycin (BLM) Induced Pulmonary Fibrosis and Carbon Tetrachloride (CCl4) Induced Hepatic Fibrosis in Mice

    Science.gov (United States)

    Chow, Leola N.; Schreiner, Petra; Ng, Betina Y. Y.; Lo, Bernard; Hughes, Michael R.; Scott, R. Wilder; Gusti, Vionarica; Lecour, Samantha; Simonson, Eric; Manisali, Irina; Barta, Ingrid; McNagny, Kelly M.; Crawford, Jason; Webb, Murray; Underhill, T. Michael

    2016-01-01

    Modulation of chemokine CXCL12 and its receptor CXCR4 has been implicated in attenuation of bleomycin (BLM)-induced pulmonary fibrosis and carbon tetrachloride (CCl4)-induced hepatic injury. In pulmonary fibrosis, published reports suggest that collagen production in the injured lung is derived from fibrocytes recruited from the circulation in response to release of pulmonary CXCL12. Conversely, in hepatic fibrosis, resident hepatic stellate cells (HSC), the key cell type in progression of fibrosis, upregulate CXCR4 expression in response to activation. Further, CXCL12 induces HSC proliferation and subsequent production of collagen I. In the current study, we evaluated AMD070, an orally bioavailable inhibitor of CXCL12/CXCR4 in alleviating BLM-induced pulmonary and CCl4-induced hepatic fibrosis in mice. Similar to other CXCR4 antagonists, treatment with AMD070 significantly increased leukocyte mobilization. However, in these two models of fibrosis, AMD070 had a negligible impact on extracellular matrix deposition. Interestingly, our results indicated that CXCL12/CXCR4 signaling has a role in improving mortality associated with BLM induced pulmonary injury, likely through dampening an early inflammatory response and/or vascular leakage. Together, these findings indicate that the CXCL12-CXCR4 signaling axis is not an effective target for reducing fibrosis. PMID:26998906

  4. Towards understanding the effects of carbon and nitrogen-doped carbon coating on the electrochemical performance of Li4Ti5O12 in lithium ion batteries: a combined experimental and theoretical study.

    Science.gov (United States)

    Ding, Zijing; Zhao, Liang; Suo, Liumin; Jiao, Yang; Meng, Sheng; Hu, Yong-Sheng; Wang, Zhaoxiang; Chen, Liquan

    2011-09-01

    We investigate the effects of carbon coating, with and without nitrogen-dopants, on the electrochemical performance of a promising anode material Li(4)Ti(5)O(12) (LTO) in lithium ion battery applications. The comparative experimental results show that LTO samples coated with nitrogen-doped carbon derived from pyridine and an ionic liquid exhibit significant improvements in rate capability and cycling performance compared with a LTO sample coated by carbon derived from toluene and the pristine LTO sample. For the first time, we construct an atomistic model for the interface between the lithium transition metal oxide and carbon coating layers. Our first-principles calculations based on density functional theory reveal that at this interface there is strong binding between the graphene coating layer and the Ti-terminated LTO surface, which significantly reduces the chemical activity of LTO surfaces and stabilizes the electrode/electrolyte interface, providing a clue to solve the swelling problem for LTO-based batteries. More importantly, electron transfer from the LTO surface to graphene greatly improves the electric conductivity of the interface. Nitrogen-dopants in graphene coatings further increase the interfacial stability and electric conductivity, which is beneficial to the electrochemical performance in energy storage applications.

  5. Measurement of Charge Asymmetries in Charmless Hadronic B Meson Decays

    CERN Document Server

    Chen, S; Hinson, J W; Lee, J; Menon, N; Miller, D H; Shibata, E I; Shipsey, I P J; Pavlunin, V; Cronin-Hennessy, D; Kwon, Y; Lyon, A L; Thorndike, E H; Jessop, C P; Marsiske, H; Perl, Martin Lewis; Savinov, V; Ugolini, D W; Zhou, X; Coan, T E; Fadeev, V; Maravin, Y; Narsky, I; Stroynowski, R; Ye, J; Wlodek, T; Artuso, M; Ayad, R; Boulahouache, C; Bukin, K; Dambasuren, E; Karamov, S; Kopp, S E; Majumder, G; Moneti, G C; Mountain, R; Schuh, S; Skwarnicki, T; Stone, S; Viehhauser, G; Wang, J C; Wolf, A; Wu, J; Csorna, S E; Danko, I; McLean, K W; Marka, S; Xu, Z; Godang, R; Kinoshita, K; Lai, I C; Schrenk, S; Bonvicini, G; Cinabro, D; Perera, L P; Zhou, G J; Eigen, G; Lipeles, E; Schmidtler, M; Shapiro, A; Sun, W M; Weinstein, A J; Würthwein, F; Jaffe, D E; Masek, G E; Paar, H P; Potter, E M; Prell, S; Sharma, V; Asner, D M; Eppich, A; Gronberg, J B; Hill, T S; Lange, D J; Morrison, R J; Nelson, H N; Briere, R A; Behrens, B H; Ford, W T; Gritsan, A; Roy, J D; Smith, J G; Alexander, J P; Baker, R; Bebek, C; Berger, B E; Berkelman, K; Blanc, F; Boisvert, V; Cassel, David G; Dickson, M; Drell, P S; Ecklund, K M; Ehrlich, R; Foland, A D; Gaidarev, P B; Gibbons, L K; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hopman, P I; Jones, C D; Kreinick, D L; Lohner, M; Magerkurth, A; Meyer, T O; Mistry, N B; Ng, C R; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Thayer, J G; Thies, P G; Valant-Spaight, B L; Warburton, A; Avery, P; Prescott, C; Rubiera, A I; Yelton, J; Zheng, J; Brandenburg, G; Ershov, A; Gao, Y S; Kim, D Y J; Wilson, R; Browder, T E; Li, Y; Rodríguez, J L; Yamamoto, H; Bergfeld, T; Eisenstein, B I; Ernst, J; Gladding, G E; Gollin, G D; Hans, R M; Johnson, E; Karliner, I; Marsh, M A; Palmer, M; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Janicek, R; Patel, P M; Sadoff, A J; Ammar, R; Bean, A; Besson, D; Davis, R; Kravchenko, I V; Kwak, N; Zhao, X; Anderson, S; Frolov, V V; Kubota, Y; Lee, S J; Mahapatra, R; O'Neill, J J; Poling, R A; Riehle, T; Smith, A; Urheim, J; Ahmed, S; Alam, M S; Athar, S B; Jian, L; Ling, L; Mahmood, A H; Saleem, M; Timm, S; Wappler, F; Anastassov, A; Duboscq, J E; Gan, K K; Gwon, C; Hart, T; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Lorenc, J; Pedlar, T K; Schwarthoff, H; Von Törne, E; Zoeller, M M; Richichi, S J; Severini, H; Skubic, P L; Undrus, A

    2000-01-01

    We search for CP-violating asymmetries (Acp) in the B meson decays to K+- pi-+, K+- pi0, Ks pi+-, K+- eta', and omega pi+-. Using 9.66 million Upsilon(4S) decays collected with the CLEO detector, the statistical precision on Acp is in the range of \\pm 0.12 to \\pm 0.25 depending on decay mode. While CP-violating asymmetries of up to \\pm 0.5 are possible within the Standard Model, the measured asymmetries are consistent with zero in all five decay modes studied.

  6. Glutamine Synthetases GLN1;2 and GLN2 in Relation to Arabidopsis Growth Response to Elevated Atmospheric Carbon Dioxide and Varying Nitrogen Forms

    DEFF Research Database (Denmark)

    Vurrakula, Swathi

    cues and adjusting it to the plant internal status. The two major types of GS include cytosolic GS1 (five isoforms in Arabidopsis, GLN1;1 to GLN1;5) and a single chloroplastic GS2. GS draws its substrates from carbon skeletons to synthesize amino acids. Thus, carbon and nitrogen metabolisms are closely....... Plants grown under elevated CO2 absorbed ammonia from the atmosphere, except with a high ammonium supply. GLN1;2 had a non-redundant role in determining vegetative growth and ammonium tolerance in response to elevated CO2. Under elevated CO2, GLN1;2 was compensable by GLN2 in assimilating nitrate...... but not ammonium. Reduced GS1 activity correlated with increased ammonia emissions from leaf surface, markedly so with an increased supply of both ammonium and CO2. GLN1;2 was also found to play a vital role in assimilating high levels of nitrate. Under current CO2 levels (400ppm) GLN2 had a non-redundant role...

  7. Evaluation of microwave and magnetic properties of substituted SrFe{sub 12}O{sub 19} and substituted SrFe{sub 12}O{sub 19}/multi-walled carbon nanotubes nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Asghari, Mahboubeh, E-mail: asghari_1420m@yahoo.com [Materials Engineering Department, Malek Ashtar University of Technology, Shahin Shahr (Iran, Islamic Republic of); Ghasemi, Ali; Paimozd, Ebrahim [Materials Engineering Department, Malek Ashtar University of Technology, Shahin Shahr (Iran, Islamic Republic of); Morisako, Akimitsu [Spin Device Technology Center, Faculty of Engineering, Shinshu University, Nagano (Japan)

    2013-12-16

    SrFe{sub 12−x}Cr{sub x/2}Al{sub x/2}O{sub 19} (x = 0–2.5) nanoparticles and ferrite/multi-walled carbon nanotubes (MWCNTs) nanocomposites were synthesized by a sol–gel method. The XRD patterns show a relatively weak peak around 26{sup °} which is corresponding to the graphite (002) lattice plane of the MWCNTs. The peak of Fourier transform infrared spectroscopy (FTIR) at 1729 cm{sup −1} can be assigned to C=O bond of carboxylic groups, indicating the presence of poly(acrylic acid) (PAA) chains in PAA–carbon nanotubes. Field emission scanning electron microscopy (FE-SEM) micrographs demonstrate that strontium ferrite nanoparticles are strung along the MWCNTs. Transmission electron microscopy (TEM) was employed to study the structure of MWCNTs. Vibrating sample magnetometer (VSM) measurements show that with an increase in x content, the values of saturation of magnetization of SrFe{sub 12−x}Cr{sub x/2}Al{sub x/2}O{sub 19} nanoparticles reduce, while coercivity increases. Results of reflection loss indicate that with adding Cr–Al cations and MWCNTs to strontium ferrite; it is possible to cover a wideband of electromagnetic waves in the frequency range of 50–74 and 12–18 GHz. In addition, it can be seen that the strontium ferrite nanoparticles and nanocomposites display a great potential application as wideband electromagnetic wave absorbers. - Highlights: • We synthesized SrFe{sub 12−x}Cr{sub x/2}Al{sub x/2}O{sub 19} nanoparticles and ferrite/MWCNTs nanocomposites. • Strontium ferrite nanoparticles attached along the surface of modified CNTs. • With an increase in x content, M{sub s} in Sr ferrite particles reduced while H{sub c} increased. • Nanocomposites have more effective microwave absorption than nanoparticles.

  8. Modelling study on production cross sections of {sup 111}In radioisotopes used in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Kara, Ayhan; Korkut, Turgay [Sinop Univ. (Turkey). Faculty of Engineering; Yigit, Mustafa [Aksaray Univ. (Turkey). Faculty of Science and Arts; Tel, Eyyup [Osmaniye Korkut Ata Univ. (Turkey). Faculty of Science and Arts

    2015-07-15

    Radiopharmaceuticals are radioactive drugs used for diagnosis or treatment in a tracer quantity with no pharmacological action. The production of radiopharmaceuticals is carried out in the special research centers generally using by the cyclotron systems. Indium-111 is one of the most useful radioisotopes used in nuclear medicine. In this paper, we calculated the production cross sections of {sup 111}In radioisotope via {sup 111-114}Cd(p,xn) nuclear reactions up to 60 MeV energy. In the model calculations, ALICE/ASH, TALYS 1.6 and EMPIRE 3.2 Malta nuclear reaction code systems were used. The model calculation results were compared to the experimental literature data and TENDL-2014 (TALYS-based) data.

  9. Performance of Silicon Betavoltaic Device by using a Ni-63 Radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Jung, H. K.; Lee, N. H.; Lee, J. S.; Cheong, Y. M. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2007-07-01

    Semiconductor betavoltaic converters use energy from radioisotope sources to generate electricity for remote applications requiring a long life power. Radioisotopes emitting {beta} radiation such as Ni-63 and tritium (H-3) have been used as fuel for low power batteries. Significant advantages of a high energy density, the insensitivity to climates and a longer life than chemical batteries make them attractive candidates for nano-power sources. The betavoltaic effect is the generation of a potential due to a net positive charge flow of an electron-induced electron-hole production (EHP). Because the resulting current is from an n-type to a p-type semiconductor, the net power can be extracted. Hence, the objective of this study is to provide the feasibility of nuclear beta sources for supplying a power to realistic MEMS devices.

  10. Recovery of radioisotopes from nuclear waste for radio-scintillator-luminescence energy applications

    CERN Document Server

    Bennun, Alfred

    2012-01-01

    Extraction of the light weight radioisotopes (LWR) 89Sr/90Sr, from the expended nuclear bars in the Fukushima reactor, should have decreased the extent of contamination during the course of the accident. 89Sr applications could pay for the extraction of 89Sr/90Sr from nuclear residues. Added value could be obtained by using 89Sr for cancer treatments. Known technologies could be used to relate into innovative ways LWR, to obtain nuclear energy at battery scale. LWR interact by contact with scintillators converting \\beta-radiation into light-energy. This would lead to manufacturing scintillator lamps which operate independently of other source of energy. These lamps could be used to generate photoelectric energy. Engineering of radioisotopes scintillator photovoltaic cells, would lead to devices without moving parts.

  11. Safety analysis for the Galileo light-weight radioisotope heater unit

    Science.gov (United States)

    Johnson, Ernest W.

    The Light-Weight Radioisotope Heater Unit (LWRHU) will be used on the NASA Galileo Mission to provide thermal energy to the various systems on the orbiter and probe that are adversely affected by the low temperature a spacecraft encounters during a long interplanetary mission. Using these plutonia-fueled sources in 1-W increments permits employment of a single design and provides the spacecraft user the option of how many to use and where to position them to satisfy the proper thermal environment for components requiring such consideration. The use of the radioisotope Pu 238 in these devices necessitates the assessment of postulated radiological risks which might be experienced in case of accidents or malfunctions of the space shuttle or the spacecraft during phases of the mission in the vicinity of the earth. Included are data for the design, mission descriptions, postulated accidents with their consequences, test data, and the derived source terms and personnel exposures for the various events.

  12. Radioisotope thermal photovoltaic application of the GaSb solar cell

    Science.gov (United States)

    Morgan, M. D.; Horne, W. E.; Day, A. C.

    1991-01-01

    An examination of a RTVP (radioisotopic thermophotovoltaic) conceptual design has shown a high potential for power densities well above those achievable with radioisotopic thermoelectric generator (RTG) systems. An efficiency of 14.4 percent and system specific power of 9.25 watts/kg were predicted for a system with sixteen GPHS (general purpose heat source) sources operating at 1100 C. The models also showed a 500 watt system power by the strontium-90 isotope at 1200 C at an efficiency of 17.0 percent and a system specific power of 11.8 watts/kg. The key to this level of performance is a high-quality photovoltaic cell with narrow bandgap and a reflective rear contact. Recent work at Boeing on GaSb cells and transparent back GaAs cells indicate that such a cell is well within reach.

  13. Effect of amplified spontaneous emission on selectivity of laser photoionisation of the 177Lu radioisotope

    Science.gov (United States)

    D'yachkov, A. B.; Gorkunov, A. A.; Labozin, A. V.; Mironov, S. M.; Panchenko, V. Ya; Firsov, V. A.; Tsvetkov, G. O.

    2016-06-01

    A significant deselecting effect of amplified spontaneous emission has been observed in the experiments on selective laser photoionisation of the 177Lu radioisotope according to the scheme 5d6s2 2D3/2 → 5d6s6p 4Fo5/2 (18505 cm-1) → 5d6s7s 4D3/2(37194 cm-1) → autoionisation state (53375 cm-1). The effect is conditioned by involvement of non-target isotopes from the lower metastable level 5d6s2 2D5/2(1994 cm-1) into the ionisation process. Spectral filtering of spontaneous emission has allowed us to significantly increase the selectivity of the photoionisation process of the radioisotope and to attain a selectivity value of 105 when using saturating light intensities.

  14. Novel decapeptides that bind avidly and deliver radioisotope to colon cancer cells.

    Directory of Open Access Journals (Sweden)

    John M Abraham

    Full Text Available The rapidly growing field of targeted tumor therapy often utilizes an antibody, sometimes tagged with a tumor-ablating material such as radioisotope, directed against a specific molecule.This report describes the discovery of nine novel decapeptides which can be radioactively labeled, bind to, and deliver (32P to colon cancer cells. The decapeptides vary from one another by one to three amino acids and demonstrate vastly different binding abilities. The most avidly binding decapeptide can permanently deliver very high levels of radioisotope to the adenocarcinoma cancer cell lines at an efficiency 35 to 150 times greater than to a variety of other cell types, including cell lines derived from other types of cancer or from normal tissue.This experimental approach represents a new example of a strategy, termed peptide binding therapy, for the potential treatment of colorectal and other adenocarcinomas.

  15. Recent research activities and future subjects on stable- and radio-isotopes of chlorine in environment

    Energy Technology Data Exchange (ETDEWEB)

    Kushita, Kouhei [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-12-01

    This report reviews the recent studies on the stable- and radio-isotopes of chlorine from a viewpoint of environmental science, partly including historic references on this element. First, general properties, occurrence, and utilization of chlorine are described. Secondly, current status and research works on chlorine-compounds, which attract special attention in recent years as environmentally hazardous materials, are reported. Thirdly, research works on stable chlorine isotopes, {sup 35}Cl and {sup 37}Cl, are described with a focus laid on the newly-developed techniques; isotopic ratio mass spectrometry (IRMS) and thermal ionization mass spectrometry (TIMS). Fourthly, recent research works on chlorine radioisotopes, {sup 36}Cl etc., are described, focusing on the development of accelerator mass spectrometry (AMS) and its application to geochemistry and others. Finally, taking account of the above-mentioned recent works on Cl isotopes, possible future research subjects are discussed. (author)

  16. Stripping voltammetric determination of Cd(Ⅱ) based on multiwalled carbon nanotube functionalized with 1-(2-pyridylazo)-2-naphthol

    Institute of Scientific and Technical Information of China (English)

    Alireza Mohadesi; Hadi Beitollahi; Mohammad Ali Karimi

    2011-01-01

    The present work has focused on the modification of multiwalled carbon nanotube with a ligand, l-(2-pyridylazo)-2-naphthol, and its potential application for the development of a new, simple and selective modified glassy carbon electrode for stripping voltammetric determination of Cd(Ⅱ). The analytical curve for Cd(Ⅱ) ions covered the linear range varying from 0.8 up to 220.4 μg L-1. The limit of detection was found to be 0.1 μg L-1, while the relative standard deviation (RSD) at 50.0 μg L-1 was 1.8% (n = 5). This modified electrode was successfully applied for determination of Cd(Ⅱ) in some water samples.

  17. Structural water cluster as a possible proton acceptor in the adduct decay reaction of oat phototropin 1 LOV2 domain.

    Science.gov (United States)

    Chan, Ruby H; Bogomolni, Roberto A

    2012-09-06

    LOV domains (Light, Oxygen, Voltage) are the light-sensory modules of phototropins, the blue-light photoreceptor kinases in plants, and of a wide variety of flavoproteins found in all three domains of life. These 12 kDa modules bind a flavin chromophore (FMN or FAD) noncovalently and undergo a photochemical activation in which the sulfur atom of a conserved cysteine forms an adduct to the C(4a) carbon of the flavin. The adduct breaks spontaneously in a base-catalyzed reaction involving a rate-limiting proton-transfer step, regenerating the dark state in seconds. This photocycle involves chromophore and protein structural changes that activate the C-terminal serine/threonine kinase. Previous studies (Biochemistry 2007, 46, 7016-7021) showed that decreased hydration obtained at high glycerol concentrations stabilizes the adduct state in a manner similar to that attained at low temperatures, resulting in much longer adduct decay times. This kinetic effect was attributed to an increased protein rigidity that hindered structural fluctuations necessary for the decay reaction. In this work, we studied the adduct decay kinetics of oat phototropin 1 (phot1) LOV2 at varying hydration using a specially designed chamber that allowed for measurement of UV-visible and FTIR spectra of the same samples. Therefore, we obtained LOV protein concentrations, adduct decay kinetics, and the different populations of bound water by deconvolution of the broad water absorption peak around 3500 cm(-1). A linear dependence of the adduct decay rate constant on the concentration of double and triple hydrogen-bonded waters strongly suggests that the adduct decay is a pseudo-first-order reaction in which both the adduct and the strongly bound waters are reactants. We suggest that a cluster of strongly bound water functions as the proton acceptor in the rate-limiting step of adduct decay.

  18. Thermal-hydraulics Analysis of a Radioisotope-powered Mars Hopper Propulsion System

    Energy Technology Data Exchange (ETDEWEB)

    Robert C. O' Brien; Andrew C. Klein; William T. Taitano; Justice Gibson; Brian Myers; Steven D. Howe

    2011-02-01

    Thermal-hydraulics analyses results produced using a combined suite of computational design and analysis codes are presented for the preliminary design of a concept Radioisotope Thermal Rocket (RTR) propulsion system. Modeling of the transient heating and steady state temperatures of the system is presented. Simulation results for propellant blow down during impulsive operation are also presented. The results from this study validate the feasibility of a practical thermally capacitive RTR propulsion system.

  19. Glue-sniffing as a cause of a positive radio-isotope brain scan

    Energy Technology Data Exchange (ETDEWEB)

    Lamont, C.M.; Adams, F.G.

    1982-08-01

    Convulsions are a known complication of the acute intoxicant effects of solvent abuse. A radio-isotope brain scan done 9 months following status epilepticus secondary to toluene inhalation, in a previously normal school-boy, demonstrated several wedge-shaped areas of increased uptake, in both cerebral hemispheres, consistent with infarcts. It is worth remembering that a positive brain scan in a young person, with recent onset of epilepsy, may be due to glue-sniffing.

  20. Theoretical cross section calculations of medical 13N and 18F radioisotope using alpha induced reaction

    Science.gov (United States)

    Kılınç, F.; Karpuz, N.; ćetin, B.

    2017-02-01

    In medical physics, radionuclides are needed to diagnose functional disorders of organs and to diagnose and treat many diseases. Nuclear reactions are significant for the productions of radionuclides. It is important to analyze the cross sections for much different energy. In this study, reactional cross sections calculations on 13N, 18F radioisotopes are with TALYS 1.6 nuclear reaction simulation code. Cross sections calculated and experimental data taken from EXFOR library were compared

  1. Quasifree Lambda, Sigma^0, and Sigma^- electroproduction from 1,2H, 3,4He, and Carbon

    Energy Technology Data Exchange (ETDEWEB)

    F. Dohrmann; A. Ahmidouch; C.S. Armstrong; J. Arrington; R. Asaturyan; S. Avery; K. Bailey; H. Bitao; H. Breuer; D.S. Brown; R. Carlini; J. Cha; N. Chant; E. Christy; A. Cochran; L. Cole; J. Crowder; S. Danagoulian; M. Elaasar; R. Ent; H. Fenker; Y. Fujii; L. Gan; K. Garrow; D.F. Geesaman; P. Gueye; K. Hafidi; W. Hinton; H. Juengst; C. Keppel; Y. Liang; J.H. Liu; A. Lung; D. Mack; P. Markowitz; J. Mitchell; T. Miyoshi; H. Mkrtchyan; S.K. Mtingwa; B. Mueller; G. Niculescu; I. Niculescu; D. Potterveld; B.A. Raue; P.E. Reimer; J. Reinhold; J. Roche; M. Sarsour; Y. Sato; R.E. Segel; A. Semenov; S. Stepanyan; V. Tadevosyan; S. Tajima; L. Tang; A. Uzzle; S. Wood; H. Yamaguchi; C. Yan; L. Yuan; B. Zeidman; M. Zeier; B. Zihlmann

    2007-07-30

    Kaon electroproduction from light nuclei and hydrogen, using 1H, 2H, 3He, 4He, and Carbon targets has been measured at Jefferson Laboratory. The quasifree angular distributions of Lambda and Sigma hyperons were determined at Q^2= 0.35(GeV/c)^2 and W= 1.91GeV. Electroproduction on hydrogen was measured at the same kinematics for reference.

  2. Nuclear energy in the service of biomedicine: the U.S. Atomic Energy Commission's radioisotope program, 1946-1950.

    Science.gov (United States)

    Creager, Angela N H

    2006-01-01

    The widespread adoption of radioisotopes as tools in biomedical research and therapy became one of the major consequences of the "physicists' war" for postwar life science. Scientists in the Manhattan Project, as part of their efforts to advocate for civilian uses of atomic energy after the war, proposed using infrastructure from the wartime bomb project to develop a government-run radioisotope distribution program. After the Atomic Energy Bill was passed and before the Atomic Energy Commission (AEC) was formally established, the Manhattan Project began shipping isotopes from Oak Ridge. Scientists and physicians put these reactor-produced isotopes to many of the same uses that had been pioneered with cyclotron-generated radioisotopes in the 1930s and early 1940s. The majority of early AEC shipments were radioiodine and radiophosphorus, employed to evaluate thyroid function, diagnose medical disorders, and irradiate tumors. Both researchers and politicians lauded radioisotopes publicly for their potential in curing diseases, particularly cancer. However, isotopes proved less successful than anticipated in treating cancer and more successful in medical diagnostics. On the research side, reactor-generated radioisotopes equipped biologists with new tools to trace molecular transformations from metabolic pathways to ecosystems. The U.S. government's production and promotion of isotopes stimulated their consumption by scientists and physicians (both domestic and abroad), such that in the postwar period isotopes became routine elements of laboratory and clinical use. In the early postwar years, radioisotopes signified the government's commitment to harness the atom for peace, particularly through contributions to biology, medicine, and agriculture.

  3. Kinetics of Chlorine Decay in Water Distribution Systems

    Institute of Scientific and Technical Information of China (English)

    周建华; 薛罡; 赵洪宾; 汪永辉; 郭美芳

    2004-01-01

    A combined first and second-order model, which includes bulk decay and wall decay, was developed to describe chlorine decay in water distribution systems. In the model the bulk decay has complex relationships with total organic carbon (TOC), the initial chlorine concentration and the temperature. Except for the initial stages they can be simplified into a linear increase with TOC, a linear decrease with initial chlorine concentration and an exponential relationship with the temperature. The model also explains why chlorine decays rapidly in the initial stages. The parameters of model are determined by deriving the best fitness with experimental data. And the accuracy of model has been verified by using the experimental data and the monitoring data in a distribution system.

  4. Radioisotope identification method for poorly resolved gamma-ray spectrum of nuclear security concern

    Energy Technology Data Exchange (ETDEWEB)

    Ninh, Giang Nguyen; Phongphaeth, Pengvanich, E-mail: phongphaeth.p@chula.ac.th; Nares, Chankow [Nuclear Engineering Department, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330 (Thailand); Hao, Quang Nguyen [Vietnam Atomic Energy Institute, Ministry of Science and Technology, Hanoi (Viet Nam)

    2016-01-22

    Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials security at the border control point, the detection task can present a significant challenge due to various constraints such as the limited measurement time, the shielding conditions, and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved gamma-ray spectrum. In this method, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of the continuum background is performed using the baseline determination algorithm. Finally, the identification of radioisotope is completed using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios including single source, mixing of natural uranium with five of the most common industrial radioactive sources (57Co, 60Co, 133Ba, 137Cs, and 241Am). The preliminary results show that the proposed algorithm is comparable with the commercial method.

  5. NASA Glenn Research Center Support of the Advanced Stirling Radioisotope Generator Project

    Science.gov (United States)

    Wilson, Scott D.; Wong, Wayne A.

    2015-01-01

    A high-efficiency radioisotope power system was being developed for long-duration NASA space science missions. The U.S. Department of Energy (DOE) managed a flight contract with Lockheed Martin Space Systems Company to build Advanced Stirling Radioisotope Generators (ASRGs), with support from NASA Glenn Research Center. DOE initiated termination of that contract in late 2013, primarily due to budget constraints. Sunpower, Inc., held two parallel contracts to produce Advanced Stirling Convertors (ASCs), one with Lockheed Martin to produce ASC-F flight units, and one with Glenn for the production of ASC-E3 engineering unit "pathfinders" that are built to the flight design. In support of those contracts, Glenn provided testing, materials expertise, Government-furnished equipment, inspection capabilities, and related data products to Lockheed Martin and Sunpower. The technical support included material evaluations, component tests, convertor characterization, and technology transfer. Material evaluations and component tests were performed on various ASC components in order to assess potential life-limiting mechanisms and provide data for reliability models. Convertor level tests were conducted to characterize performance under operating conditions that are representative of various mission conditions. Despite termination of the ASRG flight development contract, NASA continues to recognize the importance of high-efficiency ASC power conversion for Radioisotope Power Systems (RPS) and continues investment in the technology, including the continuation of the ASC-E3 contract. This paper describes key Government support for the ASRG project and future tests to be used to provide data for ongoing reliability assessments.

  6. Test Program for Stirling Radioisotope Generator Hardware at NASA Glenn Research Center

    Science.gov (United States)

    Lewandowski, Edward J.; Bolotin, Gary S.; Oriti, Salvatore M.

    2015-01-01

    Stirling-based energy conversion technology has demonstrated the potential of high efficiency and low mass power systems for future space missions. This capability is beneficial, if not essential, to making certain deep space missions possible. Significant progress was made developing the Advanced Stirling Radioisotope Generator (ASRG), a 140-W radioisotope power system. A variety of flight-like hardware, including Stirling convertors, controllers, and housings, was designed and built under the ASRG flight development project. To support future Stirling-based power system development NASA has proposals that, if funded, will allow this hardware to go on test at the NASA Glenn Research Center. While future flight hardware may not be identical to the hardware developed under the ASRG flight development project, many components will likely be similar, and system architectures may have heritage to ASRG. Thus, the importance of testing the ASRG hardware to the development of future Stirling-based power systems cannot be understated. This proposed testing will include performance testing, extended operation to establish an extensive reliability database, and characterization testing to quantify subsystem and system performance and better understand system interfaces. This paper details this proposed test program for Stirling radioisotope generator hardware at NASA Glenn. It explains the rationale behind the proposed tests and how these tests will meet the stated objectives.

  7. Radioisotope identification method for poorly resolved gamma-ray spectrum of nuclear security concern

    Science.gov (United States)

    Ninh, Giang Nguyen; Phongphaeth, Pengvanich; Nares, Chankow; Hao, Quang Nguyen

    2016-01-01

    Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials security at the border control point, the detection task can present a significant challenge due to various constraints such as the limited measurement time, the shielding conditions, and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved gamma-ray spectrum. In this method, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of the continuum background is performed using the baseline determination algorithm. Finally, the identification of radioisotope is completed using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios including single source, mixing of natural uranium with five of the most common industrial radioactive sources (57Co, 60Co, 133Ba, 137Cs, and 241Am). The preliminary results show that the proposed algorithm is comparable with the commercial method.

  8. The Copper Radioisotopes: A Systematic Review with Special Interest to 64Cu

    Directory of Open Access Journals (Sweden)

    Artor Niccoli Asabella

    2014-01-01

    Full Text Available Copper (Cu is an important trace element in humans; it plays a role as a cofactor for numerous enzymes and other proteins crucial for respiration, iron transport, metabolism, cell growth, and hemostasis. Natural copper comprises two stable isotopes, 63Cu and 65Cu, and 5 principal radioisotopes for molecular imaging applications (60Cu, 61Cu, 62Cu, and 64Cu and in vivo targeted radiation therapy (64Cu and 67Cu. The two potential ways to produce Cu radioisotopes concern the use of the cyclotron or the reactor. A noncopper target is used to produce noncarrier-added Cu thanks to a chemical separation from the target material using ion exchange chromatography achieving a high amount of radioactivity with the lowest possible amount of nonradioactive isotopes. In recent years, Cu isotopes have been linked to antibodies, proteins, peptides, and nanoparticles for preclinical and clinical research; pathological conditions that influence Cu metabolism such as Menkes syndrome, Wilson disease, inflammation, tumor growth, metastasis, angiogenesis, and drug resistance have been studied. We aim to discuss all Cu radioisotopes application focusing on 64Cu and in particular its form 64CuCl2 that seems to be the most promising for its half-life, radiation emissions, and stability with chelators, allowing several applications in oncological and nononcological fields.

  9. Multi-layer electrode with nano-Li4Ti5O12 aggregates sandwiched between carbon nanotube and graphene networks for high power Li-ion batteries.

    Science.gov (United States)

    Choi, Jin-Hoon; Ryu, Won-Hee; Park, Kyusung; Jo, Jeong-Dai; Jo, Sung-Moo; Lim, Dae-Soon; Kim, Il-Doo

    2014-12-05

    Self-aggregated Li4Ti5O12 particles sandwiched between graphene nanosheets (GNSs) and single-walled carbon nanotubes (SWCNTs) network are reported as new hybrid electrodes for high power Li-ion batteries. The multi-layer electrodes are fabricated by sequential process comprising air-spray coating of GNSs layer and the following electrostatic spray (E-spray) coating of well-dispersed colloidal Li4Ti5O12 nanoparticles, and subsequent air-spray coating of SWCNTs layer once again. In multi-stacked electrodes of GNSs/nanoporous Li4Ti5O12 aggregates/SWCNTs networks, GNSs and SWCNTs serve as conducting bridges, effectively interweaving the nanoporous Li4Ti5O12 aggregates, and help achieve superior rate capability as well as improved mechanical stability of the composite electrode by holding Li4Ti5O12 tightly without a binder. The multi-stacked electrodes deliver a specific capacity that maintains an impressively high capacity of 100 mA h g(-1) at a high rate of 100C even after 1000 cycles.

  10. Multi-layer electrode with nano-Li4Ti5O12 aggregates sandwiched between carbon nanotube and graphene networks for high power Li-ion batteries

    Science.gov (United States)

    Choi, Jin-Hoon; Ryu, Won-Hee; Park, Kyusung; Jo, Jeong-Dai; Jo, Sung-Moo; Lim, Dae-Soon; Kim, Il-Doo

    2014-12-01

    Self-aggregated Li4Ti5O12 particles sandwiched between graphene nanosheets (GNSs) and single-walled carbon nanotubes (SWCNTs) network are reported as new hybrid electrodes for high power Li-ion batteries. The multi-layer electrodes are fabricated by sequential process comprising air-spray coating of GNSs layer and the following electrostatic spray (E-spray) coating of well-dispersed colloidal Li4Ti5O12 nanoparticles, and subsequent air-spray coating of SWCNTs layer once again. In multi-stacked electrodes of GNSs/nanoporous Li4Ti5O12 aggregates/SWCNTs networks, GNSs and SWCNTs serve as conducting bridges, effectively interweaving the nanoporous Li4Ti5O12 aggregates, and help achieve superior rate capability as well as improved mechanical stability of the composite electrode by holding Li4Ti5O12 tightly without a binder. The multi-stacked electrodes deliver a specific capacity that maintains an impressively high capacity of 100 mA h g-1 at a high rate of 100C even after 1000 cycles.

  11. Beta and muon decays

    Energy Technology Data Exchange (ETDEWEB)

    Galindo, A.; Pascual, P.

    1967-07-01

    These notes represent a series of lectures delivered by the authors in the Junta de Energia Nuclear, during the Spring term of 1965. They were devoted to graduate students interested in the Theory of Elementary Particles. Special emphasis was focussed into the computational problems. Chapter I is a review of basic principles (Dirac equation, transition probabilities, final state interactions.) which will be needed later. In Chapter II the four-fermion punctual Interaction is discussed, Chapter III is devoted to the study of beta-decay; the main emphasis is given to the deduction of the formulae corresponding to electron-antineutrino correlation, electron energy spectrum, lifetimes, asymmetry of electrons emitted from polarized nuclei, electron and neutrino polarization and time reversal invariance in beta decay. In Chapter IV we deal with the decay of polarized muons with radiative corrections. Chapter V is devoted to an introduction to C.V.C. theory. (Author)

  12. Suppressed Charmed B Decay

    Energy Technology Data Exchange (ETDEWEB)

    Snoek, Hella Leonie [Vrije Univ., Amsterdam (Netherlands)

    2009-06-02

    This thesis describes the measurement of the branching fractions of the suppressed charmed B0 → D*- a0+ decays and the non-resonant B0 → D*- ηπ+ decays in approximately 230 million Υ(4S) → B$\\bar{B}$ events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B0 → D*- a{sub 0}+ decays show large QCD model dependent uncertainties. Non-factorizing terms, in the naive factorization model, that can be calculated by QCD factorizing models have a large impact on the branching fraction of these decay modes. The predictions of the branching fractions are of the order of 10-6. The measurement of the branching fraction gives more insight into the theoretical models. In general a better understanding of QCD models will be necessary to conduct weak interaction physics at the next level. The presence of CP violation in electroweak interactions allows the differentiation between matter and antimatter in the laws of physics. In the Standard Model, CP violation is incorporated in the CKM matrix that describes the weak interaction between quarks. Relations amongst the CKM matrix elements are used to present the two relevant parameters as the apex of a triangle (Unitarity Triangle) in a complex plane. The over-constraining of the CKM triangle by experimental measurements is an important test of the Standard Model. At this moment no stringent direct measurements of the CKM angle γ, one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle γ can be performed using the decays of neutral B mesons. The B0 → D*- a0+ decay is sensitive to the angle γ and, in comparison to the current decays that are being employed, could significantly

  13. Holographic Glueball Decay

    CERN Document Server

    Brünner, Frederic; Rebhan, Anton

    2014-01-01

    We announce new results on glueball decay rates in the Sakai-Sugimoto model, a realization of holographic QCD from first principles that has only one coupling constant and an overall mass scale as free parameters. We extend a previous investigation by Hashimoto, Tan, and Terashima who have considered the lowest scalar glueball which arises from a somewhat exotic polarization of supergravity modes and whose mass is uncomfortably small in comparison with lattice results. On the other hand, the scalar glueball dual to the dilaton turns out to have a mass of about twice the mass of the rho meson (1487 MeV), very close to the scalar meson $f_0(1500)$ that is frequently interpreted as predominantly glue. Calculating the decay rate into two pions we find a surprisingly good agreement with experimental data for the $f_0(1500)$. We have also obtained decay widths for tensor and excited scalar glueballs, indicating universal narrowness.

  14. Technology for safe treatment of radioisotope organic wastes

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Jin; Park, Chong Mook; Choi, W. K.; Lee, K. W.; Moon, J. K.; Yang, H. Y.; Kim, B. T.; Park, S. C

    1999-12-01

    An examination of chemical and radiological characteristics of RI organic liquid waste, wet oxidation by Fenton reaction and decomposition liquid waste treatment process were studied. These items will be applied to develop the equipment of wet oxidation and decomposition liquid waste treatment mixed processes for the safe treatment of RI organic liquid waste which is consisted of organic solvents such as toluene, alcohol and acetone. Two types of toluene solutions were selected as a candidate decomposition material. As for the first type, the concentration of toluene was above 20 vol percent. As for the second type, the solubility of toluene was considered. The decomposition ration by Fenton reaction was above 95 percent for both of them. From the adsorption equilibrium tests, a -Na{sup +} substituted/acid treated activated carbon and Zeocarbon mixed adsorbent was selected for the fixed adsorption column. This mixed adsorbent will be used to obtain the basic design data of liquid waste purification equipment for the treatment of decomposition liquid waste arising from the wet oxidation process. Solidification and degree of strength tests were performed with the simulated sludge/spent adsorbent of MgO as an oxide type and KH{sub 2}PO{sub 4}. From the test results, the design and fabrication of wet oxidation and liquid waste purification process equipment was made, and a performance test was carried out. (author)

  15. The decay of wood in landfills in contrasting climates in Australia.

    Science.gov (United States)

    Ximenes, Fabiano; Björdal, Charlotte; Cowie, Annette; Barlaz, Morton

    2015-07-01

    Wood products in landfill are commonly assumed to decay within several decades, returning the carbon contained therein to the atmosphere, with about half the carbon released as methane. However, the rate and extent of decay is not well known, as very few studies have examined the decay of wood products in landfills. This study reports on the findings from landfill excavations conducted in the Australian cities of Sydney and Cairns located in temperate and tropical environments, respectively. The objective of this study was to determine whether burial of the wood in warmer, more tropical conditions in Cairns would result in greater levels of decay than occurs in the temperate environment of Sydney. Wood samples recovered after 16-44years in landfill were examined through physical, chemical and microscopic analyses, and compared with control samples to determine the carbon loss. There was typically little or no decay in the wood samples analysed from the landfill in Sydney. Although there was significant decay in rainforest wood species excavated from Cairns, decay levels for wood types that were common to both Cairns and Sydney landfills were similar. The current Intergovernmental Panel on Climate Change (IPCC, 2006) default decay factor for organic materials in landfills is 50%. In contrast, the carbon loss determined for Pinus radiata recovered from Sydney and Cairns landfills was 7.9% and 4.4%, respectively, and 0% for Agathis sp. This suggests that climate did not influence decay, and that the more extensive levels of decay observed for some wood samples from Cairns indicates that those wood types were more susceptible to biodegradation. Microscopic analyses revealed that most decay patterns observed in samples analysed from Sydney were consistent with aerobic fungal decay. Only a minor portion of the microbial decay was due to erosion bacteria active in anaerobic/near anaerobic environments. The findings of this study strongly suggest that models that adopt

  16. Flavor changing nucleon decay

    Science.gov (United States)

    Maekawa, Nobuhiro; Muramatsu, Yu

    2017-04-01

    Recent discovery of neutrino large mixings implies the large mixings in the diagonalizing matrices of 5 bar fields in SU (5) grand unified theory (GUT), while the diagonalizing matrices of 10 fields of SU (5) are expected to have small mixings like Cabibbo-Kobayashi-Maskawa matrix. We calculate the predictions of flavor changing nucleon decays (FCND) in SU (5), SO (10), and E6 GUT models which have the above features for mixings. We found that FCND can be the main decay mode and play an important role to test GUT models.

  17. Thick-target neutron, gamma-ray, and radionuclide production for protons below 12 MeV on nickel and carbon beam-stops

    Energy Technology Data Exchange (ETDEWEB)

    Chadwick, M.B.; Young, P.G.; Wilson, W.B.

    1998-03-01

    Nuclear model calculations using the GNASH code are described for protons below 12 MeV incident on nickel and carbon isotopes, for beam stop design in the Los Alamos Accelerator Production of Tritium Low Energy Demonstration Accelerator (LEDA) project. The GNASH calculations apply Hauser-Feshbach and preequilibrium reaction theories and can make use of pre-calculated direct reaction cross sections to low-lying residual nucleus states. From calculated thin target cross sections, thick target 6.7 MeV and 12 MeV proton-induced production of neutrons, gamma rays, and radionuclides are determined. Emission spectra of the secondary neutrons and gamma rays are also determined. The model calculations are validated through comparisons with experimental thin- and thick-target measurements. The results of this work are being utilized as source terms in MCNP analyses for LEDA.

  18. Comprehensive quantitative and qualitative liquid chromatography-radioisotope-mass spectrometry analysis for safety testing of tolbutamide metabolites without standard samples.

    Science.gov (United States)

    Tozuka, Zenzaburo; Aoyama, Shinsuke; Nozawa, Kohei; Akita, Shoji; Oh-Hara, Toshinari; Adachi, Yasuhisa; Ninomiya, Shin-ichi

    2011-09-01

    Liquid chromatography-radioisotope-mass spectrometry (LC-RI-MS) analysis was used to determine the structures of 12 (four previously unknown) (14) C-tolbutamide (TB) metabolites in rat biological samples (plasma, urine, bile, feces, and microsomes). The four novel metabolites are ω-carboxy TB, hydroxyl TB (HTB)-O-glucuronide, TB-ortho or meta-glutathion, and tolylsulphoaminocarbo-glutathion. In rat plasma, after oral administration of (14) C-TB at therapeutic dose (1 mg/kg) and microdose (1.67 µg/kg), the total RI and six metabolites [HTB, carboxy TB (CTB), M1: desbutyl TB, M2: ω-hydroxyl TB, M3: α-hydroxyl TB, and M4: ω-1-hydroxyl TB] were quantified by LC-RI-MS. The plasma concentrations were calculated using their response factors (MS-RI intensity ratio) without standard samples, and the area under the curve (AUC) of plasma concentration per time for evaluation of Safety Testing of Drug Metabolites (MIST) was calculated using the ratio of TB metabolites AUC/total RI AUC. The ratios were as follows: TB 94.5% and HTB 2.5% for the microdose (1.67 µg/kg) and TB 95.6%, HTB 0.96%, CTB 0.065%, M1 0.62%, M2 0.0035%, M3 0.077%, and M4 0.015% for the therapeutic dose (1 mg/kg). These values were less than 10% of the MIST criteria.

  19. Radioisotope thermophotovoltaic system design and its application to an illustrative space mission

    Science.gov (United States)

    Schock, A.; Kumar, V.

    1995-01-01

    The paper describes the results of a DOE-sponsored design study of a radioisotope thermophotovoltaic generator (RTPV), to complement similar studies of Radioisotope Thermoelectric Generators (RTGs) and Stirling Generators (RSGs) previously published by the author. Instead of conducting a generic study, it was decided to focus the design effort by directing it at a specific illustrative space mission, Pluto Fast Flyby (PFF). That mission, under study by JPL, envisages a direct eight-year flight to Pluto (the only unexplored planet in the solar system), followed by comprehensive mapping, surface composition, and atmospheric structure measurements during a brief flyby of the planet and its moon Charon, and transmission of the recorded science data to Earth during a post-encounter cruise lasting up to one year. Because of Pluto's long distance from the sun (30-50 A.U.) and the mission's large energy demand, JPL has baselined the use of a radioisotope power system for the PFF spacecraft. TRGs have been tentatively selected, because they have been successfully flown on many space missions, and have demonstrated exceptional reliability and durability. The only reason for exploring the applicability of the far less mature RTPV systems is their potential for much higher conversion efficiencies, which would greatly reduce the mass and cost of the required radioisotope heat source. Those attributes are particularly important for the PFF mission, which—like all NASA missions under current consideration—is severely mass- and cost-limited. The paper describes the design of the radioisotope heat source, the thermophotovoltaic converter, and the heat rejection system; and depicts its integration with the PFF spacecraft. A companion paper presented at this conference presents the results of the thermal, electrical, and structural analysis and the design optimization of the integrated RTPV system. It also discusses the programmatic implications of the analytical results, which

  20. Synthesis of graphitized carbon, nanodiamond and graphene supported Li4Ti5O12 and comparison of their electrochemical performance as anodes for lithium ion batteries

    Science.gov (United States)

    Yang, Shuai; Miao, Juan; Wang, Qiufen; Lu, Mengwei; Sun, Jiufang; Wen, Tao

    2016-12-01

    Graphitized carbon (GC), nanodiamond (ND) and graphene (GE) supported Li4Ti5O12 (LTO) composites have been synthesized via a solid-state reaction, respectively. The particle sizes of LTO/GC, LTO/ND and LTO/GE are smaller than pure LTO. When tested as the anode for lithium ion batteries, the discharge capacities of LTO, LTO/GC, LTO/ND and LTO/GE composites are 100.1 mAh g-1, 150.4 mAh g-1, 90.4 mAh g-1 and 218.3 mAh g-1 at the current density of 175 mA g-1 after 500 cycles. Their rate capacities retain 59.8%, 80.0%, 81.0% and 85.7% at the current density of 175 mA g-1, 438 mA g-1, 875 mA g-1 and 175 mA g-1, respectively. Moreover, the recovery rates of their rate capacities are 78.6%, 83.4%, 88.9% and 90.1% when returned to the current density of 175 mA g-1, respectively. The reasons can be attributed to the synergistic effect between GC (ND and GE) and LTO as well as the features of the different carbon supports. This strategy, with the carbon constituting a good supporting structure, is an effective way to improve the cycling performance of anode materials for lithium ion batteries.

  1. Cluster correlation effects in 12C+12C and 14N+10B fusion-evaporation reactions

    Directory of Open Access Journals (Sweden)

    Morelli L.

    2015-01-01

    Full Text Available The decay of highly excited states of 24Mg is studied in fusion evaporation events completely detected in charge in the reactions 12C+12C and 14N+10B at 95 and 80 MeV incident energy respectively. The comparison of light charged particles measured spectra with statistical model predictions suggests that the dominant reaction mechanism is compound nucleus (CN formation and decay. However, in both reactions, a discrepancy with statistical expectations is found for α particles detected in coincidence with Carbon, Oxigen and Neon residues. The comparison between the two reactions shows that this discrepancy is only partly explained by an entrance channel effect. Evidence for cluster correlations in excited 24Mg CN is suggested by the comparison between the measured and calculated branching ratios for the channels involving α particles.

  2. The decrease of carbonation efficiency of CaO along calcination-carbonation cycles: Experiments and modelling

    Energy Technology Data Exchange (ETDEWEB)

    Bouquet, E.; Leyssens, G.; Schonnenbeck, C.; Gilot, P. [Laboratoire de Gestion des Risques et Environnement, Mulhouse (France)

    2009-05-15

    Successive calcination-carbonation cycles, using CaO as sorbent, have been performed either in a classical fixed bed reactor or using a thermogravimetric analyser. Significant differences in carbonation efficiencies were obtained, possibly due to different conditions prevailing for CaO sintering during the calcination stage. The effect of the presence of CO{sub 2} on sintering was confirmed. A simple model of the decay of the carbonation capacity along cycles based on the specific surface area of non-sintered micrograins of CaO is able to predict the decrease of the extent of conversion obtained after 40 carbonations along calcination-carbonation cycles. The asymptotic extent of conversion is obtained when all the micrograins present within a grain are sintered. A detailed model of the carbonation shows that the voids present between the micrograins are filled up by carbonate when a critical thickness of the carbonate layer around each micrograin reaches 43 nm. Then, carbonation becomes controlled by diffusion at the scale of the whole grain, with the CO{sub 2} diffusion coefficient decreasing (at 650 {sup o}C) from 2 x 10{sup -12} to 6.5 x 10{sup -14} m{sup 2}/s as carbonation proceeds from 50% conversion to 76% (first cycle). This scale change for diffusion is responsible for the drastic decrease of the carbonation rate after the voids between micrograins are filled up.

  3. Carbon Isotope Fractionation in Reactions of 1,2-Dibromoethane with FeS and Hydrogen Sulfide

    Science.gov (United States)

    EDB (1,2-dibromoethane) is frequently detected at sites impacted by leaded gasoline. In reducing environments, EDB is highly susceptible to abiotic degradation. A study was conducted to evaluate the potential of compound-specific isotope analysis (CSIA) in assessing abiotic degr...

  4. Advances of Palladium-Catalyzed 1,2-Addition of Organohalide to Carbon-Heteroatom Multibond%钯催化的有机卤化物的1,2-加成反应研究进展

    Institute of Scientific and Technical Information of China (English)

    陈程; 吴良; 葛晨; 叶仕春; 贾义霞; 高建荣

    2013-01-01

    钯催化有机卤代烃参与的对碳杂原子重键化合物的1,2-加成反应,可以有效避免传统Grignard反应、Barbier反应中活泼有机金属试剂的制备,简化合成操作并提高底物官能团的适应性,具有良好的应用前景。本文对近年来该类反应在合成化学中的发展进行了综述。%Palladium-catalyzed 1,2-addition reaction of organohalide to carbon-heteroatom multibond effectively avoids the preparation of active organometallic reagent (commonly used in the traditional Grignard, Barbier reactions), and simplifies the synthetic process and improves scope of the substrate bearing different functional groups. This review summarized recent advances of this 1,2-addition reaction in organic chemistry.

  5. Feasibility study of production of radioactive carbon black or carbon nanotubes in cyclotron facilities for nanobioscience applications.

    Science.gov (United States)

    Abbas, K; Simonelli, F; Holzwarth, U; Cydzik, I; Bulgheroni, A; Gibson, N; Kozempel, J

    2013-03-01

    A feasibility study regarding the production of radioactive carbon black and nanotubes has been performed by proton beam irradiation. Experimental and theoretical excitation functions of the nuclear reaction (nat)C(p,x)(7)Be in the proton energy range 24-38 MeV are reported, with an acceptable agreement. We have demonstrated that sufficient activities of (7)Be radioisotope can be produced in carbon black and nanotube that would facilitate studies of their possible impact on human and environment.

  6. Search for dark matter in final states with an energetic jet, or a hadronically decaying W or Z boson using $12.9~\\mathrm{fb}^{-1}$ of data at $\\sqrt{s} = 13~\\mathrm{TeV}$

    CERN Document Server

    CMS Collaboration

    2016-01-01

    A search for dark matter is performed using events with large missing transverse momentum and one or more energetic jets in a data sample of proton-proton collisions at $\\sqrt{s} = 13~\\mathrm{TeV}$, collected with the CMS detector at the LHC in the first half of 2016. The search includes events in which a hadronically decaying W or Z boson is produced in association with large missing transverse momentum. Results are presented in terms of limits on the dark matter production in association with jets or vector bosons using simplified models, and on the decay of the standard model Higgs boson to invisible particles. Vector and axial-vector mediators with masses up to $1.95~\\mathrm{TeV}$ are excluded at $95\\%$ confidence level. The exclusion for pseudoscalar (scalar) mediators reaches 430 (100) GeV. The observed (expected) upper limit on the invisible branching fraction of the standard model like Higgs boson is set at $0.44$ ($0.56$) at $95\\%$ confidence level.

  7. Rare B decays at LEP

    CERN Document Server

    Kluit, P M

    2001-01-01

    The results of the LEP experiments for rare B decays will be reviewed, covering hadronic final states, radiative and other rare decays and results for the inclusive charmless branching ratio. (8 refs).

  8. A roadmap for the development and validation of coated particle fuel for future space radioisotope heater units (RHUs) and radioisotope power systems (RPSs)

    Science.gov (United States)

    Sholtis, Joseph A.

    2001-02-01

    In early 1999, coated particle fuel was identified as offering promising advancements in design flexibility, performance, specific mass and volume, as well as safety for future space radioisotope heater units (RHUs) and radioisotope power systems (RPSs). Subsequent study, conducted during Fiscal Year 1999, provided confidence that these potential benefits were substantial and demonstrable if a modest follow-on investigative test effort was pursued. This paper lays out a roadmap for both immediate and near-term decision making, as well as any full-scale development and validation of coated particle fuel undertaken for future space RHUs, and RPSs. In an effort to obtain adequate and timely information at a reasonable cost for immediate and near-term decision making, as well as any subsequent development, production, and application decisions, a four-phased regimen of testing is identified. The four phases of testing are: (1) Pre-Decisional Testing: (2) Pre-Production Analytical Verification Testing: (3) Production Quality Assurance Testing: and (4) Post-Production Safety Verification Testing. Although all four of these phases of testing are considered essential, the first two phases are especially important for immediate and near-term decisions to advance and pursue coated particle fuel for space RHUs and RPSs. The third and fourth phases of testing are primarily identified and included for completeness at this early stage. It is concluded that there is every reason to believe that the potential benefits of coated particle fuel can be readily demonstrated through a modest investigative test effort. If such an effort is pursued and proves successful, coated particle fuel could then be developed with assurance that its ultimate benefits would revolutionize the design and space use of future RHUs and RPSs. It is hoped that this paper will serve as a starting point for further discussions and more specific planning activities aimed at advancing coated particle fuel for

  9. CP-violations in decays

    Indian Academy of Sciences (India)

    Y Sakai

    2006-11-01

    Recent results on CP-violation measurements in decays from energy asymmetric -factory experiments are reported. Thanks to large accumulated data samples, CP-violations in decays in mixing-decay interference and direct CP-violation are now firmly established. The measurements of three angles of the unitarity triangle from CP-violations of decays are quite consistent with the Standard Model expectations. These results strongly support the validity of the Kobayashi-Maskawa prescription of CP-violation.

  10. Dalitz plot slope parameters for $K \\to \\pi\\pi\\pi$ decays and two particle interference

    CERN Document Server

    Martínez, M I

    2001-01-01

    We study the possible distortion of phase-space in the decays $K \\to \\pi \\pi \\pi$, which may result from final state interference among the decay products. Such distortion may influence the values of slope parameters extracted from the Dalitz plot distribution of these decays. We comment on the consequences on the magnitude of violation of the $\\mid \\Delta I \\mid = 1/2$ rule in these decays.

  11. The decay of the T=1 isospin triplet in A=12 systems: IV. The energy dependence of the asymmetry coefficientsα _{β ^ mp } of the beta-ray angular distribution in aligned12B and12N and the induced pseudotensor interaction

    Science.gov (United States)

    Szybisz, L.; Behrens, H.

    1980-12-01

    The asymmetry parametersα _{β ^ mp } of the beta-ray emitted from aligned12B and12N are evaluated as a function of the energy. The agreement with experimental differential data is excellent for bothα _{β ^ - } ( W) andα _{β ^ + } ( W). This work confirms, using available nuclear model information, that no induced pseudotensor (IPT) interaction is required for a correct theoretical interpretation of the data. An upper limit for the IPT coupling constant f T is determined from a simultaneous fit ofα _{β ^ - } ( W) andα _{β ^ + } ( W).

  12. Analysis and theoretical modeling of the 18O enriched carbon dioxide spectrum by CRDS near 1.35 μm: (I) 16O12C18O, 16O12C17O, 12C16O2 and 13C16O2

    Science.gov (United States)

    Kassi, S.; Karlovets, E. V.; Tashkun, S. A.; Perevalov, V. I.; Campargue, A.

    2017-01-01

    The room temperature absorption spectrum of 18O enriched carbon dioxide has been recorded by very high-sensitivity Cavity Ring Down spectroscopy between 6977 and 7918 cm-1 (1.43-1.26 μm). The achieved sensitivity (noise equivalent absorption αmin 8×10-11 cm-1) has allowed for the detection of more than 8600 lines belonging to 166 bands of eleven carbon dioxide isotopologues. Line intensities of the weakest observed transitions are on the order of 2×10-30 cm/molecule. In this first part, we present the results relative to the 16O12C18O, 16O12C17O, 12C16O2 and 13C16O2 isotopologues. Their absorption lines were rovibrationally assigned on the basis of the predictions of their respective effective Hamiltonian model. Overall 5476 lines were measured and assigned to 93 bands. Forty nine of them, all belonging to 16O12C18O and 16O12C17O, are reported for the first time. The studied spectral region is formed by ΔP=10-12 series of transitions, where P=2V1+V2+3V3 is the polyad number (Vi are vibrational quantum numbers). The spectroscopic parameters of 58 bands of 16O12C18O and 16O12C17O were determined from a fit of the measured line positions. An inter- and an intrapolyad resonance perturbation were identified and analyzed in the 16O12C18O spectrum. The comparison with the line positions and line intensities included in the AMES line list is discussed. Global fits of the line intensities were performed in order to (i) improve the ΔP=10 and 11 sets of the effective dipole moment parameters of 16O12C18O and the ΔP=11 set of parameters of 16O12C17O and (ii) derive for the first time the ΔP=10 and 12 parameters of 16O12C17O and 16O12C18O, respectively.

  13. Electroweak penguin B decays

    CERN Document Server

    Nikodem, Thomas

    2016-01-01

    Flavour Changing Neutral Currents (FCNC) are sensitive probes for physics beyond the Standard Model (SM), so-called New Physics. An example of a FCNC is the $b \\to s$ quark transition described by the electroweak penguin Feynman diagram shown in Figure 1. In the SM such FCNC are only allowed with a loop structure (as e:g: shown in the figure) and not by tree level processes. In the loops heavy particles appear virtually and do not need to be on shell. Therefore also not yet discovered heavy particles with up to a mass $\\mathcal{O}$(TeV) could virtually contribute significantly to observables. Several recent measurements of electroweak penguin B decays exhibit interesting tensions with SM predictions, most prominently in the angular observable $P'_5$ 5 of the decay $B^0 \\to K^{*0} \\mu^+ \\mu^1$[1], which triggered a lot of discussion in the theory community [2]-[14].

  14. Reentry response of the lightweight radioisotope heater unit resulting from a Cassini Venus-Venus-Earth-Jupiter gravity assist maneuver accident

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    Reentry analyses consisting of ablation response, thermal response and thermal stress response have been conducted on the Lightweight Radioisotope Heater Unit (LWRHU) for Cassini/Venus-Venus-Earth-Jupiter-Gravity-Assist (VVEJGA) reentry conditions. Sequential ablation analyses of the LWRHU aeroshell, and the fuel pellet have been conducted in reentry regimes where the aeroshell has been deemed to fail. The failure criterion for ablation is generally assumed to be recession corresponding to 75% and 100% of the wall thickness. The 75% recession failure criteria allows for uncertainties that result mainly because of the high energies involved in the VVEJGA reentries compared to orbital decay reentries. Risk evaluations should consider the fact that for shallow flight paths the unit may disassemble at high-altitude as a result of ablation or may remain intact with a clad that had been molten. Within the limitations of the methodologies and assumptions of the analyses, the results indicate that: (1) For a side-on stable LWRHU reentry, aeroshell ablation failures occur for all reentry angles. (2)For a side-on spinning LWRHU reentry, aeroshell ablation failures are minimal. (3) For the tumbling LWRHU reentry, the aeroshell survives for most angles. (4) For the thermostructural analyses, using both a 1% and 5% allowable strain, all reentry angles and orientations examined resulted in small localized failures, but aeroshell breach is not predicted for any case. The analyses included in this report concentrate on VVEJGA reentry scenarios. Analyses reported previously have demonstrated that the LWRHU has adequate design margin to survive reentry from orbital decay scenarios and most injection scenarios at speeds up to escape speeds. The exception is a narrow range of flight path angles that produce multiple skip trajectories which may have excessive ablation.

  15. Study of Target Fragmentation in the Interaction of 86 MeV/A $^{12}$Carbon with Tantalum, Bismuth and Uranium

    CERN Multimedia

    2002-01-01

    Using radiochemical techniques we will ; a)~~measure the target fragment mass and charge distributions from the interaction of 86~MeV/A |1|2C with Ta, Bi and U; ; b)~~measure the target fragment forward momentum and average kinetic energy using the thick target-thick catcher technique for the above reactions; and ; c)~~measure the target fragment angular and differential energy distributions using thin target-thin catcher techniques for the reactions with Ta and U. \\\\ \\\\ These measurements should allow us to better characterize the transition between low energy and realistic heavy ion reaction mechanisms.

  16. Teleportation via decay

    Indian Academy of Sciences (India)

    S Bose; P L Knight; M B Plenio; V Vedral

    2001-02-01

    We present a rare example of a decay mechanism playing a constructive role in quantum information processing. We show how the state of an atom trapped in a cavity can be teleported to a second atom trapped in a distant cavity by the joint detection of photon leakage from the cavities. The scheme, which is probabilistic, requires only a single three level atom in a cavity. We also show how this scheme can be modified to a teleportation with insurance.

  17. Charmless B decays

    Directory of Open Access Journals (Sweden)

    Martens Aurélien

    2014-04-01

    Full Text Available During 2011, LHCb has collected an integrated luminosity of 1.1 fb−1, giving rise to a large variety of measurements. Amongst these, measurements of CP violation in B decays play a central role. In particular CP violation measurements in charmless transitions of B mesons are of interest since they provide new or improved constraints on new physics contributions. These proceedings concentrate on LHCb results made publicin the first half of the year 2012.

  18. Decays of s neutrinos

    CERN Document Server

    Barradas, J E

    2003-01-01

    Based on the Minimal Supersymmetric Standard Model (MSSM), we discussed possible two body decay modes for the s neutrino v, one charged and other neutral: v -> l sub x sub 1 sup + sup - and v -> vx sub 1 sup 0 , respectively. Exploring a range of possible values for its mass, and for the chargino x sub i sup + sup - and neutralino x sub j sup 0 masses as well. We present the specific calculation for branching ratios, which are analyzed numerically. (Author)

  19. Facile Synthesis of Carbon-Coated Spinel Li4Ti5O12/Rutile-TiO2 Composites as an Improved Anode Material in Full Lithium-Ion Batteries with LiFePO4@N-Doped Carbon Cathode.

    Science.gov (United States)

    Wang, Ping; Zhang, Geng; Cheng, Jian; You, Ya; Li, Yong-Ke; Ding, Cong; Gu, Jiang-Jiang; Zheng, Xin-Sheng; Zhang, Chao-Feng; Cao, Fei-Fei

    2017-02-22

    The spinel Li4Ti5O12/rutile-TiO2@carbon (LTO-RTO@C) composites were fabricated via a hydrothermal method combined with calcination treatment employing glucose as carbon source. The carbon coating layer and the in situ formed rutile-TiO2 can effectively enhance the electric conductivity and provide quick Li(+) diffusion pathways for Li4Ti5O12. When used as an anode material for lithium-ion batteries, the rate capability and cycling stability of LTO-RTO@C composites were improved in comparison with those of pure Li4Ti5O12 or Li4Ti5O12/rutile-TiO2. Moreover, the potential of approximately 1.8 V rechargeable full lithium-ion batteries has been achieved by utilizing an LTO-RTO@C anode and a LiFePO4@N-doped carbon cathode.

  20. Analysis, optimization, and assessment of radioisotope thermophotovoltaic system design for an illustrative space mission

    Science.gov (United States)

    Schock, A.; Mukunda, M.; Or, C.; Summers, G.

    1995-01-01

    A companion paper presented at this conference described the design of a Radioisotope Thermophotovoltaic (RTPV) Generator for an illustrative space mission (Pluto Fast Flyby). It presented a detailed design of an integrated system consisting of a radioisotope heat source, a thermophotovoltaic converter, and an optimized heat rejection system. The present paper describes the thermal, electrical, and structural analyses which led to that optimized design, and compares the computed RTPV performance to that of a Radioisotope Thermoelectric Generator (RTG) designed for the same mission. RTPVs are of course much less mature than RTGs, but our results indicate that—when fully developed—they could result in a 60% reduction of the heat source's mass, cost, and fuel loading, a 50% reduction of generator mass, a tripling of the power system's specific power, and a quadrupling of its efficiency. The paper concludes by briefly summarizing the RTPV's current technology status and assessing its potential applicability for the PFF mission. For other power systems (e.g., RTGs), demonstrating their flight readiness for a long mission is a very time-consuming process to determine the long-term effect of temperature-induced degradation mechanisms. But for the case of the described RTPV design, the paper lists a number of factors, primarily its cold (0 to 10 °C) converter temperature, that may greatly reduce the need for long-term tests to demonstrate generator lifetime. In any event, our analytical results suggest that the RTPV generator, when developed by DOE and/or NASA, would be quite valuable not only for the Pluto mission but also for other future missions requiring small, long-lived, low-mass generators.

  1. Too Much of a Good Thing ? Radioisotope Power Conversion Technology and `Waste' Heat in the Titan Environment

    Science.gov (United States)

    Lorenz, Ralph

    Unlike most solar system surface environments, Titan has an atmosphere that is both cold and dense. This means heat transfer to and from a vehicle is determined by convection, rather than by radiation which dominates on Earth and Mars. With surface temperatures near 94K, batteries and systems require heating to operate. Solar power is impractical, so a spacecraft intended to operate for longer than a few hours on Titan must have a radioisotope power source (RPS). Such sources convert heat from Plutonium decay into electricity, with an efficiency that varies from about 5% for thermoelectric systems to 20% for engine cycles such as Stirling. For vehicles with 100-200W electrical power, the 500-4000 W ‘waste’ heat in the Titan environment can be valuable in that it can be exploited to maintain thermal conditions inside the vehicle. The generally benign Titan environment, and the outstanding scientific and popular interest in its exploration, has attracted a number of mission concepts including a lander for Titan’s equatorial dunefields, light gas and hot air (‘Montgolfière’) balloons, airplanes, and capsules that float on its polar seas (e.g. the proposed Titan Mare Explorer.) However, the choice of conversion technology is key to the success of these different platforms. Waste heat can perturb meteorological measurements in several ways. First by creating a warm air plume (an effect observed on Viking and Curiosity.) Second, rain or seaspray falling onto hot radiator surfaces can evaporate causing a local enhancement of methane humidity. Third, sufficiently strong heating could perturb local winds. Similar effects, and the potential generation of effervescence or even fog, may result for capsules floating in liquid hydrocarbons. For landers and drifting buoys, these perturbations may significantly degrade environmental measurements, or at least demand tall meteorology masts, for the higher waste heat output of thermoelectric systems, and a Stirling system

  2. Multifluid magnetohydrodynamic turbulent decay

    CERN Document Server

    Downes, Turlough P

    2011-01-01

    It is generally believed that turbulence has a significant impact on the dynamics and evolution of molecular clouds and the star formation which occurs within them. Non-ideal magnetohydrodynamic effects are known to influence the nature of this turbulence. We present the results of a suite of 512-cubed resolution simulations of the decay of initially super-Alfvenic and supersonic fully multifluid MHD turbulence. We find that ambipolar diffusion increases the rate of decay of the turbulence while the Hall effect has virtually no impact. The decay of the kinetic energy can be fitted as a power-law in time and the exponent is found to be -1.34 for fully multifluid MHD turbulence. The power spectra of density, velocity and magnetic field are all steepened significantly by the inclusion of non-ideal terms. The dominant reason for this steepening is ambipolar diffusion with the Hall effect again playing a minimal role except at short length scales where it creates extra structure in the magnetic field. Interestingl...

  3. Radioactive decay data tables

    Energy Technology Data Exchange (ETDEWEB)

    Kocher, D.C.

    1981-01-01

    The estimation of radiation dose to man from either external or internal exposure to radionuclides requires a knowledge of the energies and intensities of the atomic and nuclear radiations emitted during the radioactive decay process. The availability of evaluated decay data for the large number of radionuclides of interest is thus of fundamental importance for radiation dosimetry. This handbook contains a compilation of decay data for approximately 500 radionuclides. These data constitute an evaluated data file constructed for use in the radiological assessment activities of the Technology Assessments Section of the Health and Safety Research Division at Oak Ridge National Laboratory. The radionuclides selected for this handbook include those occurring naturally in the environment, those of potential importance in routine or accidental releases from the nuclear fuel cycle, those of current interest in nuclear medicine and fusion reactor technology, and some of those of interest to Committee 2 of the International Commission on Radiological Protection for the estimation of annual limits on intake via inhalation and ingestion for occupationally exposed individuals.

  4. Development of the data base for a degradation model of a selenide RTG. [Radioisotope Thermoelectric Generator

    Science.gov (United States)

    Stapfer, G.; Truscello, V. C.

    1977-01-01

    The paper is concerned with the evaluation of the materials used in a selenide radioisotope thermoelectric generator (RTG). These materials are composed of n-type gadolinium selenide and n-type copper selenide. A three-fold evaluation approach is being used: (1) the study of the rate of change of the thermal conductivity of the material, (2) the investigation of the long-term stability of the material's Seebeck voltage and electrical resistivity under current and temperature gradient conditions, and (3) determination of the physical behavior and compatibility of the material with surrounding insulation at elevated temperatures. Programmatically, the third category of characteristic evaluation is being emphasized.

  5. Development of disposal technologies for radioactive waste generated from radioisotope users and research institutes

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Akihiro; Yoshimori, Michiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-12-01

    In order to safely dispose of a radioactive waste, which is generated from radioisotope users and research institutes, investigation of characteristics of the waste and conceptual design of disposal facility were carried out. As a result of investigating JAERI that the waste has mainly been stored, it became clear that radioactivities of 19 nuclides are important from the viewpoint of the safety of the disposal. And the result of the conceptual design of disposal facilities on the assumption of 3 kinds of sites, the differences on the safety could not be recognized in either case, though the installation depth to construct the facilities influenced the economical efficiency. (author)

  6. Inorganic, Radioisotopic, and Organic Analysis of 241-AP-101 Tank Waste

    Energy Technology Data Exchange (ETDEWEB)

    Fiskum, S.K.; Bredt, P.R.; Campbell, J.A.; Farmer, O.T.; Greenwood, L.R.; Hoppe, E.W.; Hoopes, F.V.; Lumetta, G.J.; Mong, G.M.; Ratner, R.T.; Soderquist, C.Z.; Steele, M.J.; Swoboda, R.G.; Urie, M.W.; Wagner, J.J.

    2000-10-17

    Battelle received five samples from Hanford waste tank 241-AP-101, taken at five different depths within the tank. No visible solids or organic layer were observed in the individual samples. Individual sample densities were measured, then the five samples were mixed together to provide a single composite. The composite was homogenized and representative sub-samples taken for inorganic, radioisotopic, and organic analysis. All analyses were performed on triplicate sub-samples of the composite material. The sample composite did not contain visible solids or an organic layer. A subsample held at 10 C for seven days formed no visible solids.

  7. Cosmogenic and primordial radioisotopes in copper bricks shortly exposed to cosmic rays

    Science.gov (United States)

    Coarasa, I.; Amaré, J.; Cebrián, S.; Cuestá, C.; García, E.; Martínez, M.; Oliván, M. A.; Ortigoza, Y.; Ortíz de Solórzano, A.; Puimedón, J.; Sarsa, M. L.; Villar, J. A.; Villar, P.

    2016-05-01

    Cosmogenic activation is the most common source of radioactivity in copper, being 60 Co the most significant because of its long half-life (5.27 y) and saturation activity at sea level of 1 mBq/kg. Copper bricks, which had been exposed to cosmic rays for 41 days after their casting, were used to replace the internal 10 cm of the lead shielding of a HPGe detector placed at the Canfranc Underground Laboratory. We describe the outcome of the new shielding and the cosmogenic and primordial radioisotopes observed.

  8. Light Weight Radioisotope Heater Unit (LWRHU) production for the Galileo mission

    Science.gov (United States)

    Rinehart, Gary H.

    The Light Weight Radioisotope Heater Unit (LWRHU) is a (Pu-238)O2-fueled heat source designed to provide a thermal watt of power for space missions. The LWRHU will be used to maintain the temperature of various components on the spacecraft at the required level. The heat source consists of a (Pu-238)O2-fuel pellet, a Pt-30 pct Rh capsule, a pyrolytic graphite insulator, and a woven graphite aeroshell assembly. Los Alamos National Laboratory has fabricated 134 heater units which will be used on the Galileo mission.

  9. Conceptual design of a new homogeneous reactor for medical radioisotope Mo-99/Tc-99m production

    Energy Technology Data Exchange (ETDEWEB)

    Liem, Peng Hong [Nippon Advanced Information Service (NAIS Co., Inc.) Scientific Computational Division, 416 Muramatsu, Tokaimura, Ibaraki (Japan); Tran, Hoai Nam [Chalmers University of Technology, Dept. of Applied Physics, Div. of Nuclear Engineering, SE-412 96 Gothenburg (Sweden); Sembiring, Tagor Malem [National Nuclear Energy Agency (BATAN), Center for Reactor Technology and Nuclear Safety, Kawasan Puspiptek, Serpong, Tangerang Selatan, Banten (Indonesia); Arbie, Bakri [PT MOTAB Technology, Kedoya Elok Plaza Blok DA 12, Jl. Panjang, Kebun Jeruk, Jakarta Barat (Indonesia)

    2014-09-30

    To partly solve the global and regional shortages of Mo-99 supply, a conceptual design of a nitrate-fuel-solution based homogeneous reactor dedicated for Mo-99/Tc-99m medical radioisotope production is proposed. The modified LEU Cintichem process for Mo-99 extraction which has been licensed and demonstrated commercially for decades by BATAN is taken into account as a key design consideration. The design characteristics and main parameters are identified and the advantageous aspects are shown by comparing with the BATAN's existing Mo-99 supply chain which uses a heterogeneous reactor (RSG GAS multipurpose reactor)

  10. NASA's Radioisotope Power Systems Program Overview - A Focus on RPS Users

    Science.gov (United States)

    Hamley, John A.; McCallum, Peter W.; Sandifer, Carl E., II; Sutliff, Thomas J.; Zakrajsek, June F.

    2016-01-01

    The goal of NASA's Radioisotope Power Systems (RPS) Program is to make RPS ready and available to support the exploration of the solar system in environments where the use of conventional solar or chemical power generation is impractical or impossible to meet potential future mission needs. To meet this goal, the RPS Program manages investments in RPS technologies and RPS system development, working closely with the Department of Energy. This paper provides an overview of the RPS Program content and status, its collaborations with potential RPS users, and the approach employed to maintain the readiness of RPS to support future NASA mission concepts.

  11. Sourceless formation evaluation. An LWD solution providing density and neutron measurements without the use of radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, R.; Reichel, N. [Schlumberger, Sungai Buloh (Malaysia)

    2013-08-01

    For many years the industry has been searching for a way to eliminate the logistical difficulties and risk associated with deployment of radioisotopes for formation evaluation. The traditional gamma-gamma density (GGD) measurement uses the scattering of 662-keV gamma rays from a 137Cs radioisotopic source, with a 30.17-year half-life, to determine formation density. The traditional neutron measurement uses an Am-Be source emitting neutrons with an energy around 4 MeV, with a half-life of 432 years. Both these radioisotopic sources pose health, security, and environmental risks. Pulsed-neutron generators have been used in the industry for several decades in wireline tools and more recently in logging-while-drilling tools. These generators produce 14-MeV neutrons, many of which interact with the nuclei in the formation. Elastic collisions allow a neutron porosity measurement to be derived, which has been available to the industry since 2005. Inelastic interactions are typically followed by the emission of a variety of high-energy gamma rays. Similar to the case of the GGD measurement, the transport and attenuation of these gamma rays is a strong function of the formation density. However, the gamma-ray source is now distributed over a volume within the formation, where gamma rays have been induced by neutron interactions and the source can no longer be considered to be a point as in the case of a radioisotopic source. In addition, the extent of the induced source region depends on the transport of the fast neutrons from the source to the point of gamma-ray production. Even though the physics is more complex, it is possible to measure the formation density if the fast neutron transport is taken into account when deriving the density answer. This paper briefly reviews the physics underlying the sourceless neutron porosity and recently introduced neutron-gamma density (SNGD) measurement, demonstrates how they can be used in traditional workflows and illustrates their

  12. Phosphate and arsenate removal efficiency by thermostable ferritin enzyme from Pyrococcus furiosus using radioisotopes

    KAUST Repository

    Sevcenco, Ana-Maria

    2015-03-13

    Oxo-anion binding properties of the thermostable enzyme ferritin from Pyrococcus furiosus were characterized with radiography. Radioisotopes 32P and 76As present as oxoanions were used to measure the extent and the rate of their absorption by the ferritin. Thermostable ferritin proved to be an excellent system for rapid phosphate and arsenate removal from aqueous solutions down to residual concentrations at the picomolar level. These very low concentrations make thermostable ferritin a potential tool to considerably mitigate industrial biofouling by phosphate limitation or to remove arsenate from drinking water.

  13. Methods for producing Cu-67 radioisotope with use of a ceramic capsule for medical applications

    Science.gov (United States)

    Ehst, David A.; Willit, James L.

    2016-04-12

    The present invention provides a method for producing Cu67 radioisotope suitable for use in medical applications. The method comprises irradiating a metallic zinc-68 (Zn68) target within a sealed ceramic capsule with a high energy gamma ray beam. After irradiation, the Cu67 is isolated from the Zn68 by any suitable method (e.g. chemical and or physical separation). In a preferred embodiment, the Cu67 is isolated by sublimation of the zinc in a ceramic sublimation tube to afford a copper residue containing Cu67. The Cu67 can be further purified by chemical means.

  14. Electronic structure of polycrystalline Cd metal using {sup 241}Am radioisotope

    Energy Technology Data Exchange (ETDEWEB)

    Dhaka, M. S., E-mail: msdhaka75@yahoo.co.in [Department of Physics, University College of Science, M. L. S. University, Udaipur-313001 (India); Sharma, G. [Department of Pure and Applied Physics, University of Kota, Kota-324005 (India); Mishra, M. C. [Department of Physics, R. R. M. Government College, Jhunjhunu-333001 (India); Sharma, B. K. [Department of Physics, University of Rajasthan, Jaipur-302004 (India)

    2014-04-24

    Electronic structure study of the polycrystalline cadmium metal is reported. The experimental measurement is undertaken on a polycrystalline sheet sample using 59.54 keV radioisotope of {sup 241}Am. These results are compared with the ab initio calculations. The theoretical calculations are performed using linear combination of atomic orbitals (LCAO) method employing the density functional theories (DFT) and Hartree-Fock (HF) and augmented plane wave (APW) methods. The spherically averaged APW and LCAO based theoretical Compton profiles are in good agreement with the experimental measurement however the APW based theoretical calculations show best agreement.

  15. Radioisotope tracer studies in the NASA Skylab ethothermic brazing experiment M-552

    Science.gov (United States)

    Braski, D. N.; Adair, H. L.; Kobisk, E. H.

    1974-01-01

    The first use of radioisotope tracer for mapping flow patterns during brazing of metal components in a space environment (near-zero gravity) proved successful. A nickel ferrule was brazed to a nickel tube with Lithobraze BT (71.8% Ag, 28% Cu, 0.2% Li) which contained a trace amount of radioactive Ag-110. Mapping of the flow of the braze alloy in the annulus formed between the tube and the concentric ferrule was determined by counting the radiation intensity as a function of position in the braze joint. Significant information concerning the thermal history of the braze was determined.

  16. Di-proton decay of the 6.15 MeV 1- state in 18Ne

    Science.gov (United States)

    Brown, B. A.; Barker, F. C.; Millener, D. J.

    2002-05-01

    The widths for one- and two-proton decay of the 1-2 state in 18Ne are calculated. Shell-model wave functions are used to obtain the spectroscopic factors. The R-matrix theory of Barker which incorporates the final-state interaction between the two protons is used for the di-proton decay model. The calculated widths for both one- and two-proton decay are in qualitative agreement with experiment. We find that the decay width for sequential two-proton decay through the ghost of the 1/2+ bound state in 17F is comparable to the width of the direct di-proton decay.

  17. Imperfect World of beta beta-decay Nuclear Data Sets

    Energy Technology Data Exchange (ETDEWEB)

    Pritychenko, B. [Brookhaven National Lab. (BNL), Upton, NY (United States). NNDC

    2015-01-03

    The precision of double-beta ββ-decay experimental half lives and their uncertainties is reanalyzed. The method of Benford's distributions has been applied to nuclear reaction, structure and decay data sets. First-digit distribution trend for ββ-decay T2v1/2 is consistent with large nuclear reaction and structure data sets and provides validation of experimental half-lives. A complementary analysis of the decay uncertainties indicates deficiencies due to small size of statistical samples, and incomplete collection of experimental information. Further experimental and theoretical efforts would lead toward more precise values of-decay half-lives and nuclear matrix elements.

  18. Herbivore perception decreases photosynthetic carbon-assimilation and reduces stomatal conductance by engaging 12-oxo-phytodienoic acid, mitogen-activated protein kinase 4 and cytokinin perception.

    Science.gov (United States)

    Meza-Canales, Ivan D; Meldau, Stefan; Zavala, Jorge A; Baldwin, Ian T

    2016-12-07

    Herbivory-induced changes in photosynthesis have been documented in many plant species, however the complexity of photosynthetic regulation and analysis has thwarted progress in understanding the mechanism involved, particularly those elicited by herbivore-specific elicitors. Here we analyzed the early photosynthetic gas-exchange responses in Nicotiana attenuata plants after wounding and elicitation with Manduca sexta oral-secretions, and the pathways regulating these responses. Elicitation with M. sexta oral-secretions rapidly decreased photosynthetic carbon-assimilation (AC ) in treated and systemic (untreated, vascularly connected) leaves, which were associated with changes in stomatal conductance, rather than with changes in Rubisco activity and RuBP-turnover. Phytohormone profiling and gas-exchange-analysis of oral-secretion-elicited transgenic plants altered in phytohormone regulation, biosynthesis and perception, combined with micrografting techniques, revealed that the local photosynthetic-responses were mediated by 12-oxo-phytodienoic acid (OPDA), while the systemic responses involved interactions among jasmonates, cytokinins and abscisic acid signaling mediated by mitogen activated protein kinase 4 (MPK4). The analysis also revealed a role for cytokinins interacting with MPK4 in CO2 -mediated stomatal regulation. Hence oral-secretions, while eliciting jasmonic acid-mediated defense responses, also elicits OPDA-mediated changes in stomatal conductance and AC , an observation illustrating the complexity and economy of the signaling that regulates defense and carbon assimilation pathways in response to herbivore attack.

  19. Synthesis of magnetic Pb/Fe304/Si02 and its catalytic activity for propylene carbonate synthesis via urea and 1,2-propylene glycol

    Institute of Scientific and Technical Information of China (English)

    Hualiang AN; Xinqiang ZHAO; Zhiguang JIA; Changcheng WU; Yanji WANG

    2009-01-01

    To facilitate the recovery of Pb/SiO2 catalyst, magnetic Pb/Fe3O4/SiO2 samples were prepared separately by emulsification, sol-gel and incipient impregnation methods. The catalyst samples were characterized by means of X-ray diffraction and N2 adsorption-desorption, and their catalytic activity was investigated in the reaction for synthesizing propylene carbonate from urea and 1,2-propylene glycol. When the gelatin was applied in the preparation of Fe3O4 at 60°C and the pH value was controlled at 4 in the preparation of Fe3O4/SiO2, the Pb/ Fe3O4/SiO2 sample shows good catalytic activity and magnetism. Under the reaction conditions of a reaction temperature of 180°C, reaction time of 2 h, catalyst percentage of 1.7 wt-% and a molar ratio of urea to PG of 1:4, the yield of propylene carbonate attained was 87.7%.

  20. Column: Factors Affecting Data Decay

    Directory of Open Access Journals (Sweden)

    Kevin Fairbanks

    2012-06-01

    Full Text Available In nuclear physics, the phrase decay rate is used to denote the rate that atoms and other particles spontaneously decompose. Uranium-235 famously decays into a variety of daughter isotopes including Thorium and Neptunium, which themselves decay to others. Decay rates are widely observed and wildly different depending on many factors, both internal and external. U-235 has a half-life of 703,800,000 years, for example, while free neutrons have a half-life of 611 seconds and neutrons in an atomic nucleus are stable.We posit that data in computer systems also experiences some kind of statistical decay process and thus also has a discernible decay rate. Like atomic decay, data decay fluctuates wildly. But unlike atomic decay, data decay rates are the result of so many different interplaying processes that we currently do not understand them well enough to come up with quantifiable numbers. Nevertheless, we believe that it is useful to discuss some of the factors that impact the data decay rate, for these factors frequently determine whether useful data about a subject can be recovered by forensic investigation.(see PDF for full column

  1. Particle decays hint at new matter

    CERN Multimedia

    2003-01-01

    "Unexpected observations at a Japanese particle accelerator may signal the presence of previously unknown subatomic matter. The conjecture, from the so-called Belle team at the High Energy Accelerator Research Organization (KEK) in Tsukuba, was inspired by the team's measurements of a specific type of decay of fundamental particles called bottom, or b, quarks and their antimatter counter- parts, anti-b quarks" (1/2 page).

  2. Non-perturbative renormalization in kaon decays

    CERN Document Server

    Donini, Andrea; Martinelli, G; Rossi, G C; Talevi, M; Testa, M; Vladikas, A

    1996-01-01

    We discuss the application of the MPSTV non-perturbative method \\cite{NPM} to the operators relevant to kaon decays. This enables us to reappraise the long-standing question of the $\\Delta I=1/2$ rule, which involves power-divergent subtractions that cannot be evaluated in perturbation theory. We also study the mixing with dimension-six operators and discuss its implications to the chiral behaviour of the $B_K$ parameter.

  3. The decay of wood in landfills in contrasting climates in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Ximenes, Fabiano, E-mail: fabiano.ximenes@dpi.nsw.gov.au [Forest Science, Agriculture NSW, New South Wales Department of Primary Industries, Level 12, 10 Valentine Ave, Parramatta, NSW 2150 (Australia); Björdal, Charlotte [Department of Conservation, Gothenburg University, Guldhedsgatan 5A, Box 130, SE-405 30 Göteborg (Sweden); Cowie, Annette [NSW Department of Primary Industries, Beef Industry Centre, Trevenna Rd., University of New England, Armidale, NSW 2351 (Australia); Barlaz, Morton [Dept. of Civil, Construction, & Environmental Eng., North Carolina State University, Box 7908, Raleigh, NC 27695-7908 (United States)

    2015-07-15

    Highlights: • We examine decay in wood from landfills in contrasting environments in Australia. • Analysis is based on changes in chemical composition and microscopy. • Climate did not influence levels of decay observed. • Microscopy of retrieved samples revealed most of the decay was aerobic in nature. • Current default factors for wood decay in landfills overestimate methane emissions. - Abstract: Wood products in landfill are commonly assumed to decay within several decades, returning the carbon contained therein to the atmosphere, with about half the carbon released as methane. However, the rate and extent of decay is not well known, as very few studies have examined the decay of wood products in landfills. This study reports on the findings from landfill excavations conducted in the Australian cities of Sydney and Cairns located in temperate and tropical environments, respectively. The objective of this study was to determine whether burial of the wood in warmer, more tropical conditions in Cairns would result in greater levels of decay than occurs in the temperate environment of Sydney. Wood samples recovered after 16–44 years in landfill were examined through physical, chemical and microscopic analyses, and compared with control samples to determine the carbon loss. There was typically little or no decay in the wood samples analysed from the landfill in Sydney. Although there was significant decay in rainforest wood species excavated from Cairns, decay levels for wood types that were common to both Cairns and Sydney landfills were similar. The current Intergovernmental Panel on Climate Change (IPCC, 2006) default decay factor for organic materials in landfills is 50%. In contrast, the carbon loss determined for Pinus radiata recovered from Sydney and Cairns landfills was 7.9% and 4.4%, respectively, and 0% for Agathis sp. This suggests that climate did not influence decay, and that the more extensive levels of decay observed for some wood samples

  4. Peace propaganda and biomedical experimentation: influential uses of radioisotopes in endocrinology and molecular genetics in Spain (1947-1971).

    Science.gov (United States)

    Santesmases, María Jesús

    2006-01-01

    A political discourse of peace marked the distribution and use of radioisotopes in biomedical research and in medical diagnosis and therapy in the post-World War II period. This occurred during the era of expansion and strengthening of the United States' influence on the promotion of sciences and technologies in Europe as a collaborative effort, initially encouraged by the policies and budgetary distribution of the Marshall Plan. This article follows the importation of radioisotopes by two Spanish research groups, one in experimental endocrinology and one in molecular biology. For both groups foreign funds were instrumental in the early establishment of their laboratories. The combination of funding and access to previously scarce radioisotopes helped position these groups at the forefront of research in Spain.

  5. Carbon-11 pb-12: an attempt to visualize the dopamine d{sub 4} receptor in the primate brain with positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Langer, Oliver E-mail: oliver.langer@psyk.ks.se; Halldin, Christer; Chou Yuanhwa; Sandell, Johan; Swahn, Carl-Gunnar; Naagren, Kjell; Perrone, Roberto; Berardi, Francesco; Leopoldo, Marcello; Farde, Lars

    2000-11-01

    The dopamine D{sub 4} receptor (D{sub 4}R) is expressed in low density in various extrastriatal brain regions. This receptor subtype is discussed in relation to the pathophysiology and treatment of schizophrenia but no selective positron emission tomography (PET) ligand is available to date to study the distribution in vivo. The arylpiperazine derivative N-[2-[4-(4-chlorophenyl)piperazin-1-yl]ethyl]-3-methoxybenzamide (PB-12) is a novel, high-affinity ( K{sub i}=0.040 nM) and selective D{sub 4}R ligand. We radiolabeled PB-12 with carbon-11 (t{sub 1/2} 20.4 min) by O-methylation of the corresponding desmethyl analogue N-[2-[4-(4-chlorophenyl)piperazin-1-yl]ethyl]-3-hydroxybenzamide (LM-190) with [{sup 11}C]methyl triflate. Derivative LM-190 was prepared by condensing 3-hydroxybenzoic acid with the appropriate amine. For the radiolabeling, the incorporation yield was >90% and the total synthesis time including high performance liquid chromatography (HPLC) purification was about 35 min. The specific radioactivity of [{sup 11}C]PB-12 at time of injection was 67-118 GBq{center_dot}{mu}mol{sup -1}. PET studies in a cynomolgus monkey showed a high uptake and widespread distribution of radioactivity in the brain, including the neocortex and thalamus. About 40% of total radioactivity in plasma represented unchanged radioligand at 60 min after injection as determined by HPLC. Pretreatment with the D{sub 4}R ligand 3-{l_brace}[4-(4-chlorophenyl)piperazin-1-yl]methyl{r_brace}-1H-pyrollo[2,3-b]pyridine (L-745,870) prior to radioligand injection failed to demonstrate receptor-specific binding in the monkey brain. Furthermore, the brain radioactivity distribution was left unaffected by pretreating with unlabeled PB-12. This failure to detect a D{sub 4}R-specific signal may be related to a very low density of the D{sub 4}R in primate brain, insufficient binding affinity of the radioligand, and a high background of nonspecific binding. It can be concluded from these findings that

  6. Probable cluster decays from $^{270-318}$118 superheavy nuclei

    CERN Document Server

    Santhosh, K P

    2014-01-01

    The cluster decay process in $^{270-318}$118 superheavy nuclei has been studied extensively within the Coulomb and proximity potential model (CPPM), thereby investigating the probable cluster decays from the various isotopes of $Z = 118$. On comparing the predicted decay half lives with the values evaluated using the Universal formula for cluster decay (UNIV) of Poenaru et al., the Universal Decay Law (UDL) of Qi et al., and the Scaling Law of Horoi et al., it was seen that, our values matches well with these theoretical values. A comparison of the predicted alpha decay half life of the experimentally synthesized superheavy isotope $^{294}$118 with its corresponding experimental value shows that, our theoretical value is in good agreement with the experimental value. The plots for $log_{10}(T_{1/2})$ against the neutron number of the daughter in the corresponding decay reveals the behavior of the cluster half lives with the neutron number of the daughter nuclei and for most of the decays, the half life was fo...

  7. New Opportunities for Outer Solar System Science using Radioisotope Electric Propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Noble, Robert J.; /SLAC; Amini, Rashied; Beauchamp, Patricia M.; /Caltech, JPL; Bennett, Gary L.; /Metaspace Enterprises; Brophy, John R.; Buratti, Bonnie J.; Ervin, Joan; /Caltech, JPL; Fernandez, Yan R.; /Central Florida U.; Grundy, Will; /Lowell Observ.; Khan, Mohammed Omair; /Caltech, JPL; King, David Q.; /Aerojet; Lang, Jared; /Caltech, JPL; Meech, Karen J.; /Hawaii U.; Newhouse, Alan; Oleson, Steven R.; Schmidt, George R.; /GRC; Spilker, Thomas; West, John L.; /Caltech, JPL

    2010-05-26

    Today, our questions and hypotheses about the Solar System's origin have surpassed our ability to deliver scientific instruments to deep space. The moons of the outer planets, the Trojan and Centaur minor planets, the trans-Neptunian objects (TNO), and distant Kuiper Belt objects (KBO) hold a wealth of information about the primordial conditions that led to the formation of our Solar System. Robotic missions to these objects are needed to make the discoveries, but the lack of deep-space propulsion is impeding this science. Radioisotope electric propulsion (REP) will revolutionize the way we do deep-space planetary science with robotic vehicles, giving them unprecedented mobility. Radioisotope electric generators and lightweight ion thrusters are being developed today which will make possible REP systems with specific power in the range of 5 to 10 W/kg. Studies have shown that this specific power range is sufficient to perform fast rendezvous missions from Earth to the outer Solar System and fast sample return missions. This whitepaper discusses how mobility provided by REP opens up entirely new science opportunities for robotic missions to distant primitive bodies. We also give an overview of REP technology developments and the required next steps to realize REP.

  8. Potential Applications for Radioisotope Power Systems in Support of Human Exploration Missions

    Science.gov (United States)

    Cataldo, Robert L.; Colozza, Anthony J.; Schmitz, Paul C.

    2013-01-01

    Radioisotope power systems (RPS) for space applications have powered over 27 U.S. space systems, starting with Transit 4A and 4B in 1961, and more recently with the successful landing of the Mars Science Laboratory rover Curiosity in August 2012. RPS enable missions with destinations far from the Sun with faint solar flux, on planetary surfaces with dense or dusty atmospheres, and at places with long eclipse periods where solar array sizes and energy storage mass become impractical. RPS could also provide an enabling capability in support of human exploration activities. It is envisioned that with the higher power needs of most human mission concepts, a high efficiency thermal-to-electric technology would be required such as the Advanced Stirling Radioisotope generator (ASRG). The ASRG should be capable of a four-fold improvement in efficiency over traditional thermoelectric RPS. While it may be impractical to use RPS as a main power source, many other applications could be considered, such as crewed pressurized rovers, in-situ resource production of propellants, back-up habitat power, drilling, any mobile or remote activity from the main base habitat, etc. This paper will identify potential applications and provide concepts that could be a practical extension of the current ASRG design in providing for robust and flexible use of RPS on human exploration missions.

  9. System-Level Testing of the Advanced Stirling Radioisotope Generator Engineering Hardware

    Science.gov (United States)

    Chan, Jack; Wiser, Jack; Brown, Greg; Florin, Dominic; Oriti, Salvatore M.

    2014-01-01

    To support future NASA deep space missions, a radioisotope power system utilizing Stirling power conversion technology was under development. This development effort was performed under the joint sponsorship of the Department of Energy and NASA, until its termination at the end of 2013 due to budget constraints. The higher conversion efficiency of the Stirling cycle compared with that of the Radioisotope Thermoelectric Generators (RTGs) used in previous missions (Viking, Pioneer, Voyager, Galileo, Ulysses, Cassini, Pluto New Horizons and Mars Science Laboratory) offers the advantage of a four-fold reduction in Pu-238 fuel, thereby extending its limited domestic supply. As part of closeout activities, system-level testing of flight-like Advanced Stirling Convertors (ASCs) with a flight-like ASC Controller Unit (ACU) was performed in February 2014. This hardware is the most representative of the flight design tested to date. The test fully demonstrates the following ACU and system functionality: system startup; ASC control and operation at nominal and worst-case operating conditions; power rectification; DC output power management throughout nominal and out-of-range host voltage levels; ACU fault management, and system command / telemetry via MIL-STD 1553 bus. This testing shows the viability of such a system for future deep space missions and bolsters confidence in the maturity of the flight design.

  10. Radioisotope radiotherapy research and achievements at the University of Missouri Research Reactor

    Science.gov (United States)

    Ehrhardt, G. J.; Ketring, A. R.; Cutler, C. S.

    2003-01-01

    The University of Missouri Research Reactor (MURR) in collaboration with faculty in other departments at the University of Missouri has been involved in developing new means of internal radioisotopic therapy for cancer for many years. These efforts have centered on methods of targeting radioisotopes such as brachytherapy, embolisation of liver tumors with radioactive microspheres, small-molecule-labelled chelates for the treatment of bone cancer, and various means of radioimmunotherapy or labelled receptor agent targeting. This work has produced two radioactive agents, Sm-153 Quadramet™ and Y-90 TheraSphere™, which have U.S. Food and Drug Administration approval for the palliation of bone cancer pain and treatment of inoperable liver cancer, respectively. MURR has also pioneered development of other beta-emitting isotopes for internal radiotherapy such as Re-186, Re-188, Rh-105, Ho-166, Lu-177, and Pm-149, many of which are in research and clinical trials throughout the U.S. and the world. This important work has been made possible by the very high neutron flux available at MURR combined with MURR's outstanding reliability of operation and flexibility in meeting the needs of researchers and the radiopharmaceutical industry.

  11. Summary. The 19th quality control survey for radioisotope in vitro tests in Japan, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Shishiba, Yoshimasa; Shimizu, Taeko [Toranomon Hospital, Tokyo (Japan); Ichihara, Kiyoshi; Kousaka, Tadako; Kobayashi, Hisae; Tsushima, Toshio; Hoshino, Minoru; Mori, Mikio

    1998-11-01

    This summary concerns results of the survey in the title performed by the Subcommittee for Radioisotope in vitro Test in the Medical and Pharmaceutical Committee, Japan Radioisotope Association. The survey was conducted in 161 facilities in Japan including public and private hospitals, health institutes and reagent manufacturers. Samples were sent to the facilities and subjected to examinations of intra- and inter-day reproducibility, freeze-thawing effects and periodical changes of the measured values. Methods employed were RIA, IRMA, EIA, ELISA, LPIA, PAMIA, FIA, FPIA, NIA, LAT, CLIA and ECLIA. Results were analyzed by variation coefficients in the kit and between the kits. Samples were for: growth hormone, somatomedin C, follicle stimulating hormone, luteinizing hormone, prolactin, thyroid stimulating hormone, triiodothyronine, thyroxine, thyroxine binding globulin, calcitonin, insulin, C-peptide, glucagon, gastrin, testosterone, estradiol, progesterone, {beta}human chorionic gonadotropin, 17{alpha}-hydroxyprogesterone, aldosterone, cortisol, dehydroepiandrosterone, renin, immunogloblin E, digoxin, {alpha}-fetoprotein, carcinoembryonic antigen, tissue polypeptide antigen, CA125, CA19-9, CA15-3, prostatic acid phosphatase, prostate specific antigen, {beta}{sub 2}-microgloblin and ferritin. Results were found rather unsatistactory for some products in the clinical practice, necessary for improvement of detection for some tests and needed for some kits for solving the problems of difference between kits and of matrix effect. (K.H)

  12. Development of a Power Electronics Controller for the Advanced Stirling Radioisotope Generator

    Science.gov (United States)

    Leland, Douglas K.; Priest, Joel F.; Keiter, Douglas E.; Schreiber, Jeffrey G.

    2008-01-01

    Under a U.S. Department of Energy program for radioisotope power systems, Lockheed Martin is developing an Engineering Unit of the Advanced Stirling Radioisotope Generator (ASRG). This is an advanced version of the previously reported SRG110 generator. The ASRG uses Advanced Stirling Convertors (ASCs) developed by Sunpower Incorporated under a NASA Research Announcement contract. The ASRG makes use of a Stirling controller based on power electronics that eliminates the tuning capacitors. The power electronics controller synchronizes dual-opposed convertors and maintains a fixed frequency operating point. The controller is single-fault tolerant and uses high-frequency pulse width modulation to create the sinusoidal currents that are nearly in phase with the piston velocity, eliminating the need for large series tuning capacitors. Sunpower supports this effort through an extension of their controller development intended for other applications. Glenn Research Center (GRC) supports this effort through system dynamic modeling, analysis and test support. The ASRG design arrived at a new baseline based on a system-level trade study and extensive feedback from mission planners on the necessity of single-fault tolerance. This paper presents the baseline design with an emphasis on the power electronics controller detailed design concept that will meet space mission requirements including single fault tolerance.

  13. Direct CP violation in hadronic B decays

    Institute of Scientific and Technical Information of China (English)

    HONG; Bihai

    2006-01-01

    [1]Aubert B,Barate R,Boutigny D,et al.Direct CP violating asymmetry in B0 → K+π-decays.Phys Rev Lett,2004,93,131801[2]Abe K,Adachi I,Aihara H,et al.Observation of large CP violation and evidence for direct CP violation in B0 → K+π-decays.Phys Rev Lett,2004,93:021601[3]Bauer M,Stech B,Wirbel M.Exclusive semileptonic decays of heavy mesons.Z Phys C,1985,29:637-642[4]Bauer M,Stech B,Wirbel M.Exclusive nonleptonic decays of D,DS,and B mesons.Z Phys C,1987,34:103-115[5]Ali A,Kramer G,Lu C D.Experimental tests of factorization in charmless non-leptonic two-body B decays.Phys Rev D,1998,58:094009[6]Lu C D.Charmless non-leptonic two-body B decays in factorization approach.Nucl Phys Proc Supp,1999,74:227-230[7]Cheng H Y.Nonfactorizable contributions to nonleptonic weak decays of heavy mesons.Phys Lett B,1994,335:428-435[8]Cheng H Y Z.Hadronic weak decays of heavy mesons and nonfactorization.Phys Lett C,1996,69:647-654[9]Beneke M,Buchalla G,Neubert M,Sachrajda C T.QCD factorization for B0 → K+π-decays:Strong phases and CP violation in the heavy quark limit.Phys Rev Lett,1999,83:1914-1917[10]Beneke M,Buchalla G,Neubert M,Sachrajda C T.QCD factorization for exclusive,nonleptonic B meson decays:General arguments and the case of heavy light final states.Nucl Phys B,2000,591:313-418[11]Lapage G P,Brodsky S J.Exclusive processes in quantum chromodynamics:evolution equations for hadronic wave functions and the form-factors of mesons.Phys Lett B,1979,87:359-365[12]Lapage G P,Brodsky S J.Exclusive processes in perturbative quantum chromodynamics.Phys Rev D,1980,22:2157-2198[13]Huang C S.Phys Energ Fortis Et Phys Nucl,1980,4:761[14]Cao F G,Dai Y B,Huang C S.Twist-three contribution to the pion electromagnetic form-factor.Eur Phys J C,1999,11:501-506[15]Botts J,Sterman G,Hard elastic scattering in QCD:Leading behavior.Nucl Phys B,1989,325:62-100[16]Li H N,Sterman G.The perturbative pion form-factor with Sudakov suppression.Nucl Phys B,1992,381:129-140[17]Li H N,Yu H L

  14. Rare B Decays

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, P.D.; /Victoria U.

    2006-02-24

    Recent results from Belle and BaBar on rare B decays involving flavor-changing neutral currents or purely leptonic final states are presented. Measurements of the CP asymmetries in B {yields} K*{gamma} and b {yields} s{gamma} are reported. Also reported are updated limits on B{sup +} {yields} K{sup +}{nu}{bar {nu}}, B{sup +} {yields} {tau}{sup +}{nu}, B{sup +} {yields} {mu}{sup +}{nu} and the recent measurement of B {yields} X{sub s}{ell}{sup +}{ell}{sup -}.

  15. Large-angle production of charged pions by 3 GeV/c - 12 GeV/c protons on carbon, copper and tin targets

    CERN Document Server

    Catanesi, M G; Edgecock, R; Ellis, M; Robbins, S; Soler, F J P; Gössling, C; Bunyatov, S; Krasnoperov, A; Popov, B; Serdiouk, V; Tereschenko, V; Di Capua, E; Vidal-Sitjes, G; Artamonov, A; Arce, P; Giani, S; Gilardoni, S; Gorbunov, P; Grant, A; Grossheim, A; Gruber, P; Ivanchenko, V; Kayis-Topaksu, A; Panman, J; Papadopoulos, I; Pasternak, J; Chernyaev, E; Tsukerman, I; Veenhof, R; Wiebusch, C; Zucchelli, P; Blondel, A; Borghi, S; Campanelli, M; Morone, M C; Prior, G; Schroeter, R; Engel, R; Meurer, C; Kato, I; Gastaldi, Ugo; Mills, G B; Graulich, J S; Grégoire, G; Bonesini, M; Ferri, F; Paganoni, M; Paleari, F; Kirsanov, M; Bagulya, A; Grichine, V; Polukhina, N; Palladino, V; Coney, L; Schmitz, D; Barr, G; De Santo, A; Pattison, C; Zuber, K; Bobisut, F; Gibin, D; Guglielmi, A; Mezzetto, M; Dumarchez, J; Vannucci, F; Dore, U; Orestano, D; Pastore, F; Tonazzo, A; Tortora, L; Booth, C; Buttar, C; Hodgson, P; Howlett, L; Bogomilov, M; Chizhov, M; Kolev, D; Tsenov, R; Piperov, S; Temnikov, P; Apollonio, M; Chimenti, P; Giannini, G; Santin, G; Burguet-Castell, J; Cervera-Villanueva, A; Gómez-Cadenas, J J; Martín-Albo, J; Novella, P; Sorel, M; Tornero, A

    2008-01-01

    A measurement of the double-differential $\\pi^{\\pm}$ production cross-section in proton--carbon, proton--copper and proton--tin collisions in the range of pion momentum $100 \\MeVc \\leq p < 800 \\MeVc$ and angle $0.35 \\rad \\le \\theta <2.15 \\rad$ is presented. The data were taken with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3 \\GeVc to 12 \\GeVc hitting a target with a thickness of 5% of a nuclear interaction length. The tracking and identification of the produced particles was done using a small-radius cylindrical time projection chamber (TPC) placed in a solenoidal magnet. An elaborate system of detectors in the beam line ensured the identification of the incident particles. Results are shown for the double-differential cross-sections at four incident proton beam momenta (3 \\GeVc, 5 \\GeVc, 8 \\GeVc and 12 \\GeVc).

  16. [Effect of accelerated heavy ions of carbon 12C, neon 20Ne and iron 56Fe on the chromosomal apparatus of human blood lymphocytes in vitro].

    Science.gov (United States)

    Repina, L A

    2011-01-01

    Cytogenetic assay of the chromosomal apparatus of human blood lymphocytes was carried out after in vitro irradiation by heavy charged particles with high LET values. Blood plasm samples enriched with lymphocytes were irradiated by accelerated ions of carbon 12C (290 MeV/nucleon and LET = 70 keV/microm), neon 20Ne (400 MeV/nucleon and LET = 70 keV/microm), and iron 56Fe (500 MeV/nucleon and LET = 200 keV/microm) in the dose range from 0.25 to 1 Gy. Rate of chromosome aberrations showed a linear dependence on doses from the densely ionizing radiations with high LET values. Frequency of dicentrics and centric rings in human lymphocytes irradiated by 12C with the energy of 290 MeV/nucleon was maximal at 1 Gy (p < 0.05) relative to the other heavy particles. It was found that relative biological effectiveness of heavy nuclei is several times higher than of 60Co gamma-radiation throughout the range of doses in this investigation.

  17. Measurement of the b-Hadron Production Cross Section Using Decays to MU- d0 X Final States in p anti-p Collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Aaltonen, T.; /Helsinki Inst. of Phys.; Adelman, Jahred A.; /Chicago U., EFI; Akimoto, T.; /Tsukuba U.; Alvarez Gonzalez, B.; /Cantabria Inst. of Phys.; Amerio, S.; /INFN, Padua; Amidei, Dante E.; /Michigan U.; Anastassov, A.; /Northwestern U.; Annovi, Alberto; /Frascati; Antos, Jaroslav; /Comenius U.; Apollinari, G.; /Fermilab; Apresyan, A.; /Purdue U. /Waseda U.

    2009-03-01

    We report a measurement of the production cross section for b hadrons in p{bar p} collisions at {radical}s = 1.96 TeV. Using a data sample derived from an integrated luminosity 83 pb{sup -1} collected with the upgraded Collider Detector (CDF II) at the Fermilab Tevatron, we analyze b hadrons, H{sub b}, partially reconstructed in the semileptonic decay mode H{sub b} {yields} {mu}{sup -} D{sup 0} X. Our measurement of the inclusive production cross section for b hadrons with transverse momentum p{sub T} > 9 GeV/c and rapidity |y| < 0.6 is {sigma} = 1.30 {micro}b {+-} 0.05 {micro}b(stat) {+-} 0.14 {micro}b(syst) {+-} 0.07 {micro}b({Beta}), where the uncertainties are statistical, systematic, and from branching fractions respectively. The differential cross sections d{sigma}/d{sub T}T are found to be in good agreement with recent measurements of the H{sub b} cross section and well described by fixed-order next-to-leading logarithm predictions.

  18. Search for excited and exotic muons in the mu gamma decay channel in p anti-p collisions at s**(1/2) = 1.96-TeV

    Energy Technology Data Exchange (ETDEWEB)

    Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G.; Ambrose, D.; Amerio, S.; Amidei, D.; Anastassov, A.; Anikeev, K.; /Taiwan, Inst.

    2006-06-01

    The authors present a search for excited and exotic muon states {mu}*, conducted using an integrated luminosity of 371 pb{sup -1} of data collected in p{bar p} collisions at {radical}s = 1.96 TeV at the Tevatron with the CDF II detector. They search for associated production of {mu}{mu}* followed by the decay {mu}* {yields} {mu}{gamma}, resulting in the {mu}{mu}{gamma} final state. They compare the data to model predictions as a function of the mass of the excited muon M{sub {mu}*}, the compositeness energy scale {Lambda}, and the gauge coupling factor f. No signal above the standard model expectation is observed in the {mu}{gamma} mass spectrum. In the contact interaction model, they exclude 107 < M{sub {mu}*} < 853 GeV/c{sup 2} for {Lambda} = M{sub {mu}*}; in the gauge-mediated model, they exclude 100 < M{sub {mu}*} < 410 GeV/c{sup 2} for f/{Lambda} = 10{sup -2} GeV{sup -1}. These 95% confidence level exclusions extend previous limits and are the first hadron collider results on {mu}* production in the gauge-mediated model.

  19. Diffractively produced Z bosons in the muon decay channel in p-pbar collisions at s**(1/2) = 1.96 TeV, and the measurement of the efficiency of the D0 Run II luminosity monitor

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Tamsin L

    2006-04-01

    The first analysis of diffractively produced Z bosons in the muon decay channel is presented, using data taken by the D0 detector at the Tevatron at {radical}s = 1.96 TeV. The data sample corresponds to an integrated luminosity of 109 pb{sup -1}. The diffractive sample is defined using the fractional momentum loss {zeta} of the intact proton or antiproton measured using the calorimeter and muon detector systems. In a sample of 10791 (Z/{gamma})* {yields} {mu}{sup +}{mu}{sup -} events, 24 diffractive candidate events are found with {zeta} < 0.02. The first work towards measuring the cross section times branching ratio for diffractive production of (Z/{gamma})* {yields} {mu}{sup +}{mu}{sup -} is presented for the kinematic region {zeta} < 0.02. The first work towards measuring the cross section times branching ratio for diffractive production of (Z/{gamma})* {yields} {mu}{sup +}{mu}{sup -} is presented for the kinematic region {zeta} < 0.02. The systematic uncertainties are not yet sufficiently understood to present the cross section result. In addition, the first measurement of the efficiency of the Run II D0 Luminosity Monitor is presented, which is used in all cross section measurements. The efficiency is: {var_epsilon}{sub LM} = (90.9 {+-} 1.8)%.

  20. Search for direct photons in. Upsilon. (4 S ) decays

    Energy Technology Data Exchange (ETDEWEB)

    Narain, M.; Heintz, U.; Lee-Franzini, J.; Lovelock, D.M.J.; Schamberger, R.D.; Willins, J.; Yanagisawa, C. (Physics Department, State University of New York at Stony Brook, Stony Brook, NY (USA)); Franzini, P.; Tuts, P.M. (Columbia University, New York, NY (USA))

    1990-11-26

    We have searched for photon signals in {Upsilon}(4{ital S}) decays, indicative of large decay rates involving annihilation of the {ital b{bar b}} pair rather than decays to {ital B{bar B}} meson pairs. We do not observe any evidence for such signals. We also obtain a model-independent upper limit of (4.5--6.0)% for the branching ratio of {Upsilon}(4{ital S}){r arrow}{ital ggX}, for 0{lt}{ital M}({ital X}){lt}1.2 GeV, at 90% confidence level.