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Sample records for dubna experimental transmutation

  1. Experimental demonstration of free-space optical vortex transmutation with polygonal lenses.

    PubMed

    Gao, Nan; Xie, Changqing

    2012-08-01

    Vortex transmutation was predicted to take place when vortices interact with systems possessing discrete rotational symmetries of finite order [Phys. Rev. Lett.95, 123901 (2005)]. Here we report what is believed to be the first experimental demonstration of vortex transmutation. We show that in free space, by simply inserting polygonal lenses into the optical path, the central vorticity of a coaxially incident optical vortex can be changed following the modular transmutation rule. We generate the wavefront at the exit face of the lenses with computer generated holograms and measure the output vorticity using the interference patterns at the focal plane. The results agree well with theoretical predictions. PMID:22859150

  2. Trinity at Dubna

    SciTech Connect

    Reed, T.; Kramish, A.

    1996-11-01

    The Russian nuclear trinity{emdash}nuclear designers, spooks, and peasants{emdash}held its first reunion last May, in the town of Dubna, near Moscow. A lot of skeletons came out to dance in the warm spring sun. {copyright} {ital 1996 American Institute of Physics.}

  3. Spectroscopy of heavy elements at Dubna

    SciTech Connect

    Dorvaux, O.; Khouaja, A.; Curien, D.; Gall, B.; Khalfallah, F.; Rousseau, M.; Rowley, N.; Stuttge, V. I. L.; Yeremin, A. V.; Belozerov, A. V.; Chelnokov, M. L.; Chepigin, V. I.; Gorshkov, V. A.; Kabachenko, A. P.; Malyshev, O. N.

    2008-05-12

    In 2004, the GABRIELA (Gamma Alpha Beta Recoil Investigation with the Electromagnetic Analyzer VASSILISSA) collaboration started a twofold scientific program at the FLNR (Dubna) laboratory : (a) the systematic study of the behaviour of single particle states within isotopic and isotonic chains with Z = 100-104 as N varies from 152 to 162 and (b) the study of isotopes for which very little spectroscopic information is known. After discussing the Physics motivations and the experimental setup, some new results concerning the structure of {sup 249}Fm and {sup 253}No nuclei, and some preliminary results on the decay of {sup 217}Pa decay are presented.

  4. PREFACE: International Conference on Theoretical Physics: Dubna-Nano 2012

    NASA Astrophysics Data System (ADS)

    Osipov, Vladimir; Nesterenko, Valentin; Shukrinov, Yury M.

    2012-11-01

    The International Conference 'Dubna-Nano2012' was held on 9-14 July 2012 at the Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Moscow region, Russia. The conference was the third one in the series started in 2008. 'Dubna-Nano2012' provided an opportunity for presentations and discussions about theoretical and experimental advances in the rapidly growing area of nanophysics. The multidisciplinary character of the conference allowed an effective exchange of ideas between different areas of nanophysics. The following topics were covered: graphene and other carbon nanostructures, topological insulators, quantum transport, quantum dots, atomic clusters, Josephson junctions and applications of nanosystems. About 100 scientists from 22 countries participated in the conference. The program included 38 oral talks and 39 posters. This volume contains 35 contributions. We would like to express our gratitude to all participants for their presentations and discussions. We are deeply indebted to the members of the International Advisory Committee Professors K S Novoselov, T Ando, T Chakraborty, J Fabian, V M Galitski, F Guinea, M Z Hasan, P Hawrylak, K Kadowaki, R Kleiner, T Koyama, Yu I Latyshev, Yu E Lozovik, M Machida, B K Nikolic, N F Pedersen, P-G. Reinhard, J M Rost and A Ya Vul. Financial support from BLTP JINR, Russian Foundation for Basic Research, Heisenberg-Landau Program and Bogoliubov-Infeld Program was of a great importance. Further information about 'Dubna-Nano2012' is available on the homepage http://theor.jinr.ru/~nano12. Vladimir Osipov, Valentin Nesterenko and Yury Shukrinov Editors

  5. PREFACE International Conference on Theoretical Physics Dubna-Nano 2010

    NASA Astrophysics Data System (ADS)

    Osipov, Vladimir; Nesterenko, Valentin; Shukrinov, Yury

    2010-11-01

    The International Conference on Theoretical Physics 'Dubna-Nano2010' was held on 5-10 July 2010, at the Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Moscow region, Russia. The previous conference of this series was at Dubna in 2008. The conference provided the opportunity for the presentation and discussion of theoretical and experimental advances in the rapidly growing area of nanophysics, with the accent on its theoretical aspects. The multidisciplinary character of the conference allowed an effective exchange of ideas between different areas of nanophysics. The following topics were covered: carbon nanosystems (graphene, nanotubes, fullerenes), quantum dots, quantum transport, spectroscopy and dynamics of atomic clusters, Josephson junctions, modelling, applications and perspectives. Approximately 120 scientists from 26 countries participated in the conference. The program included 63 oral talks and 70 posters. The 62 contributions are included in these proceedings. We would like to express our gratitude to all participants for their presentations and discussions, which made the conference indeed successful. We are deeply indebted to the members of the International Advisory Committee (Professors T Ando, J Fabian, F Guinea, P Hawrylak, K Kadowaki, T Koyama, Yu I Latushev, Yu E Lozovik, M Machida, B K Nikolic, N F Pedersen, P-G Reinhard, J M Rost, A Ya Vul') and the Local Organizing Committee for their fruitful work. The financial support of BLTP JINR, Russian Foundation for Basic Research, Heisenberg-Landau Program and Bogoliubov-Infeld Program was of a great importance. Additional information about 'Dubna-Nano2010' is available at the homepage http://theor.jinr.ru/~nano10. Vladimir Osipov, Valentin Nesterenko and Yury Shukrinov Editors

  6. A new movable polarized target at Dubna

    SciTech Connect

    Anischenko, N.G.; Bazhanov, N.A.; Benda, B.; Borisov, N.S.; Borzunov, Y.T.; Burinov, V.F.; Durand, G.; Dzyubak, A.P.; Gevchuk, A.V.; Golovanov, L.B.; Gurevich, G.M.; Kovalev, A.I.; Lazarev, A.B.; Leconte, P.; Lehar, F.; de Lesquen, A.; Lukhanin, A.A.; Matafonov, V.N.; Matyushevsky, E.A.; Mironov, S.; Neganov, A.B.; Piskunov, N.M.; Plis, Y.A.; Shilov, S.N.; Shishov, Y.A.; Sorokin, P.V.; Teterin, V.V.; Topalov, S.

    1995-09-01

    A description of the recently installed mouable Polarized Proton Targe (MPT) at the JINR in Dubna is described. This target was acquired from Fermilab. The physics program based on the MPT at Dbna is outlined. (AIP) {copyright} {ital 1995 American Institute of Physics.}

  7. Neutron-induced transmutation reactions in 237Np, 238Pu, and 239Pu at the massive natural uranium spallation target

    NASA Astrophysics Data System (ADS)

    Zavorka, L.; Adam, J.; Baldin, A. A.; Caloun, P.; Chilap, V. V.; Furman, W. I.; Kadykov, M. G.; Khushvaktov, J.; Pronskikh, V. S.; Solnyshkin, A. A.; Sotnikov, V.; Stegailov, V. I.; Suchopar, M.; Tsoupko-Sitnikov, V. M.; Tyutyunnikov, S. I.; Voronko, V.; Vrzalova, J.

    2015-04-01

    Transmutation reactions in the 237Np, 238Pu, and 239Pu samples were investigated in the neutron field generated inside a massive (m = 512 kg) natural uranium spallation target. The uranium target assembly QUINTA was irradiated with the deuteron beams of kinetic energy 2, 4, and 8 GeV provided by the Nuclotron accelerator at the Joint Institute for Nuclear Research (JINR) in Dubna. The neutron-induced transmutation of the actinide samples was measured off-line by implementing methods of gamma-ray spectrometry with HPGe detectors. Results of measurement are expressed in the form of both the individual reaction rates and average fission transmutation rates. For the purpose of validation of radiation transport programs, the experimental results were compared with simulations of neutron production and distribution performed by the MCNPX 2.7 and MARS15 codes employing the INCL4-ABLA physics models and LAQGSM event generator, respectively. In general, a good agreement between the experimental and calculated reaction rates was found in the whole interval of provided beam energies.

  8. Vortex Transmutation

    SciTech Connect

    Ferrando, Albert; Garcia-March, Miguel-Angel

    2005-09-16

    Using group theory arguments and numerical simulations, we demonstrate the possibility of changing the vorticity or topological charge of an individual vortex by means of the action of a system possessing a discrete rotational symmetry of finite order. We establish on theoretical grounds a 'transmutation pass rule' determining the conditions for this phenomenon to occur and numerically analyze it in the context of two-dimensional optical lattices. An analogous approach is applicable to the problems of Bose-Einstein condensates in periodic potentials.

  9. The fast-spectrum transmutation experimental facility FASTEF: Main design achievements (Part 1: Core and primary system) within the FP7-CDT collaborative project of the European Commission

    SciTech Connect

    De Bruyn, D.; Fernandez, R.; Mansani, L.; Woaye-Hune, A.; Sarotto, M.; Bubelis, E.

    2012-07-01

    MYRRHA (Multi-purpose hybrid Research Reactor for High-tech Applications) is the flexible experimental accelerator-driven system (ADS) in development at SCK CEN in replacement of its material testing reactor BR2. SCK CEN in association with 17 European partners from industry, research centres and academia, responded to the FP7 (Seventh Framework Programme) call from the European Commission to establish a Central Design Team (CDT) for the design of a Fast Spectrum Transmutation Experimental Facility (FASTEF) able to demonstrate efficient transmutation and associated technology through a system working in subcritical and/or critical mode. The project has started on April 01, 2009 for a period of three years. In this paper, we present the latest configuration of the reactor core and primary system. The FASTEF facility has evolved quite a lot since the intermediate reporting done at the ICAPP'10 and ICAPP'11 conferences 1 2. If it remains a small-scale facility, the core power amounts now up to 100 MWth in critical mode. In a companion paper 3, we present the concept of the reactor building and the plant layout. (authors)

  10. JINR-DUBNA an International center of Nuclear Research

    NASA Astrophysics Data System (ADS)

    Gudima, K.; Baznat, M.

    2015-04-01

    A short History of the Joint Institute of the Nuclear Research in Dubna (Russian Federation) has been given. The Facilities : The Synchrophasotron, the Nuclotron-M, the IBR-2 Reactor,The Heavy Ions Isochronous cyclotrons U-400 and U-400M, Phasotron, The impuls resonance neutronic device IREN has been described. A short history of collaboration between JINR and scientists from Moldova has been given. The main new tendencies in Science management has been outlined.

  11. Nuclear transmutation in steels

    NASA Astrophysics Data System (ADS)

    Belozerova, A. R.; Shimanskii, G. A.; Belozerov, S. V.

    2009-05-01

    The investigations of the effects of nuclear transmutation in steels that are widely used in nuclear power and research reactors and in steels that are planned for the application in thermonuclear fusion plants, which are employed under the conditions of a prolonged action of neutron irradiation with different spectra, made it possible to study the effects of changes in the isotopic and chemical composition on the tendency of changes in the structural stability of these steels. For the computations of nuclear transmutation in steels, we used a program complex we have previously developed on the basis of algorithms for constructing branched block-type diagrams of nuclide transformations and for locally and globally optimizing these diagrams with the purpose of minimizing systematic errors in the calculation of nuclear transmutation. The dependences obtained were applied onto a Schaeffler diagram for steels used for structural elements of reactors. For the irradiation in fission reactors, we observed only a weak influence of the effects of nuclear transmutation in steels on their structural stability. On the contrary, in the case of irradiation with fusion neutrons, a strong influence of the effects of nuclear transmutation in steels on their structural stability has been noted.

  12. Transmutation of Long-Lived Nuclear Wastes

    NASA Astrophysics Data System (ADS)

    Oigawa, Hiroyuki

    JAEA is conducting research and development on an Accelerator Driven System (ADS), aiming at reduction of burden for high-level radioactive wastes. To tackle technical challenges on ADS, JAEA is planning to build the Transmutation Experimental Facility as the Phase-2 program of J-PARC. Moreover, JAEA is considering the collaboration with the MYRRHA project proposed by Belgian Nuclear Research Center.

  13. Proposal for New Experimental Tests of the Bose-Einstein Condensation Mechanism for Low-Energy Nuclear Reaction and Transmutation Processes in Deuterium Loaded - and Nano-Scale Cavities

    NASA Astrophysics Data System (ADS)

    Kim, Yeong E.; Koltick, David S.; Reifenberger, Ronald G.; Zubarev, Alexander L.

    2006-02-01

    Most of experimental results of low-energy nuclear reaction (LENR) reported so far cannot be reproduced on demand. There have been persistent experimental results indicating that the LENR and transmutation processes in condensed matters (LENRTPCM) are surface phenomena rather than bulk phenomena. Recently proposed Bose-Einstein condensation (BEC) mechanism may provide a suitable theoretical description of the surface phenomena. New experiments are proposed and described for testing the BEC mechanism for LENR and transmutation processes in micro- and nano-scale traps. (1) We propose the use of micro- or nano-porous conducting materials as a cathode in electrolysis experiments with heavy water with or without Li in order to stabilize the active surface spots and to enhance the effect for the purpose of improving the reproducibility of excess heat generation and nuclear emission. (2) We propose new experimental tests of the BEC mechanism by measuring the pressure and temperature dependence of LENR events using deuterium gas and these deuterated metals with or without Li. If the LENRTPCM are surface phenomena, the proposed use of micro-/nano-scale porous materials is expected to enhance and scale up the LENRTPCM effects by many order of magnitude, and thus may lead to better reproductivity and theoretical understanding of the phenomena.

  14. FCRD Transmutation Fuels Handbook 2015

    SciTech Connect

    Janney, Dawn Elizabeth; Papesch, Cynthia Ann

    2015-09-01

    Transmutation of minor actinides such as Np, Am, and Cm in spent nuclear fuel is of international interest because of its potential for reducing the long-term health and safety hazards caused by the radioactivity of the spent fuel. One important approach to transmutation (currently being pursued by the DOE Fuel Cycle Research & Development Advanced Fuels Campaign) involves incorporating the minor actinides into U-Pu-Zr alloys, which can be used as fuel in fast reactors. It is, therefore, important to understand the properties of U-Pu-Zr alloys, both with and without minor actinide additions. In addition to requiring extensive safety precautions, alloys containing U and Pu are difficult to study for numerous reasons, including their complex phase transformations, characteristically sluggish phase-transformation kinetics, tendency to produce experimental results that vary depending on the histories of individual samples, and sensitivity to contaminants such as oxygen in concentrations below a hundred parts per million. Many of the experimental measurements were made before 1980, and the level of documentation for experimental methods and results varies widely. It is, therefore, not surprising that little is known with certainty about U-Pu-Zr alloys, and that general acceptance of results sometimes indicates that there is only a single measurement for a particular property. This handbook summarizes currently available information about U, Pu, Zr, and alloys of two or three of these elements. It contains information about phase diagrams and related information (including phases and phase transformations); heat capacity, entropy, and enthalpy; thermal expansion; and thermal conductivity and diffusivity. In addition to presenting information about materials properties, it attempts to provide information about how well the property is known and how much variation exists between measurements. Although the handbook includes some references to publications about modeling

  15. The Fast-spectrum Transmutation Experimental Facility FASTEF: Main design achievements (part 2: Reactor building design and plant layout) within the FP7-CDT collaborative project of the European Commission

    SciTech Connect

    De Bruyn, D.; Engelen, J.; Ortega, A.; Aguado, M. P.

    2012-07-01

    MYRRHA (Multi-purpose hybrid Research Reactor for High-tech Applications) is the flexible experimental accelerator-driven system (ADS) in development at SCK-CEN in replacement of its material testing reactor BR2. SCK-CEN in association with 17 European partners from industry, research centres and academia, responded to the FP7 (Seventh Framework Programme) call from the European Commission to establish a Central Design Team (CDT) for the design of a Fast Spectrum Transmutation Experimental Facility (FASTEF) able to demonstrate efficient transmutation and associated technology through a system working in subcritical and/or critical mode. The project has started on April 01, 2009 for a period of three years. In this paper, we present the latest concept of the reactor building and the plant layout. The FASTEF facility has evolved quite a lot since the intermediate reporting done at the ICAPP'10 and ICAPP'11 conferences 1,2. Many iterations have been performed to take into account the safety requirements. The present configuration enables an easy operation and maintenance of the facility, including the possibility to change large components of the reactor. In a companion paper 3, we present the latest configuration of the reactor core and primary system. (authors)

  16. Separations technology development to support accelerator-driven transmutation concepts

    SciTech Connect

    Venneri, F.; Arthur, E.; Bowman, C.

    1996-10-01

    This is the final report of a one-year Laboratory-Directed Research and Development (LDRD) Project at the Los Alamos National Laboratory (LANL). This project investigated separations technology development needed for accelerator-driven transmutation technology (ADTT) concepts, particularly those associated with plutonium disposition (accelerator-based conversion, ABC) and high-level radioactive waste transmutation (accelerator transmutation of waste, ATW). Specific focus areas included separations needed for preparation of feeds to ABC and ATW systems, for example from spent reactor fuel sources, those required within an ABC/ATW system for material recycle and recovery of key long-lived radionuclides for further transmutation, and those required for reuse and cleanup of molten fluoride salts. The project also featured beginning experimental development in areas associated with a small molten-salt test loop and exploratory centrifugal separations systems.

  17. Nuclear data for nuclear transmutation

    SciTech Connect

    Harada, Hideo

    2009-05-04

    Current status on nuclear data for the study of nuclear transmutation of radioactive wastes is reviewed, mainly focusing on neutron capture reactions. It is stressed that the highest-precision frontier research in nuclear data measurements should be a key to satisfy the target accuracies on the nuclear data requested for realizing the nuclear transmutation.

  18. Automation of experiments at Dubna Gas-Filled Recoil Separator

    NASA Astrophysics Data System (ADS)

    Tsyganov, Yu. S.

    2016-01-01

    Approaches to solving the problems of automation of basic processes in long-term experiments in heavy ion beams of the Dubna Gas-Filled Recoil Separator (DGFRS) facility are considered. Approaches in the field of spectrometry, both of rare α decays of superheavy nuclei and those for constructing monitoring systems to provide accident-free experiment running with highly radioactive targets and recording basic parameters of experiment, are described. The specific features of Double Side Silicon Strip Detectors (DSSSDs) are considered, special attention is paid to the role of boundary effects of neighboring p-n transitions in the "active correlations" method. An example of an off-beam experiment attempting to observe Zeno effect is briefly considered. Basic examples for nuclear reactions of complete fusion at 48Ca ion beams of U-400 cyclotron (LNR, JINR) are given. A scenario of development of the "active correlations" method for the case of very high intensity beams of heavy ions at promising accelerators of LNR, JINR, is presented.

  19. Transmutations in fusion test facilities

    SciTech Connect

    Mann, F.M.

    1986-04-01

    Using an expanded nuclear data base, the transmutation of PCA, AMCR33 (a reduced activation austenitic steel), HT-9, Rafer2 (a reduced activation ferritic steel), V-15%Cr-5%Ti alloy, and SiAlON (a ceramic) were calculated for two positions in the Fast Flux Test Facility (FFTF), three positions in the High Flux Isotope Reactor (HFIR), and the first wall position of both the STARFIRE and MARS conceptual fusion reactors. The peripheral test (PTP) position, and to a lesser extent the radial beryllium (RB) position, of HFIR show significant transmutations which are often in the opposite direction to the transmutations in the fusion conceptual designs. The positions in FFTF, as well as the hafnium covered location in the HFIR RB position show relative minor transmutations.

  20. Transmutation of actinides in power reactors.

    PubMed

    Bergelson, B R; Gerasimov, A S; Tikhomirov, G V

    2005-01-01

    Power reactors can be used for partial short-term transmutation of radwaste. This transmutation is beneficial in terms of subsequent storage conditions for spent fuel in long-term storage facilities. CANDU-type reactors can transmute the main minor actinides from two or three reactors of the VVER-1000 type. A VVER-1000-type reactor can operate in a self-service mode with transmutation of its own actinides. PMID:16604724

  1. Neutron transmutation doped Ge bolometers

    NASA Technical Reports Server (NTRS)

    Haller, E. E.; Kreysa, E.; Palaio, N. P.; Richards, P. L.; Rodder, M.

    1983-01-01

    Some conclusions reached are as follow. Neutron Transmutation Doping (NTD) of high quality Ge single crystals provides perfect control of doping concentration and uniformity. The resistivity can be tailored to any given bolometer operating temperature down to 0.1 K and probably lower. The excellent uniformity is advantaged for detector array development.

  2. Nuclear Methods for Transmutation of Nuclear Waste: Problems, Perspextives, Cooperative Research - Proceedings of the International Workshop

    NASA Astrophysics Data System (ADS)

    Khankhasayev, Zhanat B.; Kurmanov, Hans; Plendl, Mikhail Kh.

    1996-12-01

    The Table of Contents for the full book PDF is as follows: * Preface * I. Review of Current Status of Nuclear Transmutation Projects * Accelerator-Driven Systems — Survey of the Research Programs in the World * The Los Alamos Accelerator-Driven Transmutation of Nuclear Waste Concept * Nuclear Waste Transmutation Program in the Czech Republic * Tentative Results of the ISTC Supported Study of the ADTT Plutonium Disposition * Recent Neutron Physics Investigations for the Back End of the Nuclear Fuel Cycle * Optimisation of Accelerator Systems for Transmutation of Nuclear Waste * Proton Linac of the Moscow Meson Factory for the ADTT Experiments * II. Computer Modeling of Nuclear Waste Transmutation Methods and Systems * Transmutation of Minor Actinides in Different Nuclear Facilities * Monte Carlo Modeling of Electro-nuclear Processes with Nonlinear Effects * Simulation of Hybrid Systems with a GEANT Based Program * Computer Study of 90Sr and 137Cs Transmutation by Proton Beam * Methods and Computer Codes for Burn-Up and Fast Transients Calculations in Subcritical Systems with External Sources * New Model of Calculation of Fission Product Yields for the ADTT Problem * Monte Carlo Simulation of Accelerator-Reactor Systems * III. Data Basis for Transmutation of Actinides and Fission Products * Nuclear Data in the Accelerator Driven Transmutation Problem * Nuclear Data to Study Radiation Damage, Activation, and Transmutation of Materials Irradiated by Particles of Intermediate and High Energies * Radium Institute Investigations on the Intermediate Energy Nuclear Data on Hybrid Nuclear Technologies * Nuclear Data Requirements in Intermediate Energy Range for Improvement of Calculations of ADTT Target Processes * IV. Experimental Studies and Projects * ADTT Experiments at the Los Alamos Neutron Science Center * Neutron Multiplicity Distributions for GeV Proton Induced Spallation Reactions on Thin and Thick Targets of Pb and U * Solid State Nuclear Track Detector and

  3. Industrial research for transmutation scenarios

    NASA Astrophysics Data System (ADS)

    Camarcat, Noel; Garzenne, Claude; Le Mer, Joël; Leroyer, Hadrien; Desroches, Estelle; Delbecq, Jean-Michel

    2011-04-01

    This article presents the results of research scenarios for americium transmutation in a 22nd century French nuclear fleet, using sodium fast breeder reactors. We benchmark the americium transmutation benefits and drawbacks with a reference case consisting of a hypothetical 60 GWe fleet of pure plutonium breeders. The fluxes in the various parts of the cycle (reactors, fabrication plants, reprocessing plants and underground disposals) are calculated using EDF's suite of codes, comparable in capabilities to those of other research facilities. We study underground thermal heat load reduction due to americium partitioning and repository area minimization. We endeavor to estimate the increased technical complexity of surface facilities to handle the americium fluxes in special fuel fabrication plants, americium fast burners, special reprocessing shops, handling equipments and transport casks between those facilities.

  4. Requirements for GNEP Transmutation Fuels

    SciTech Connect

    D. C. Crawford; M. K. Meyer; S. L. Hayes

    2007-03-01

    The purpose of this document is to provide a baseline set of requirements to guide fuel fabrication development and irradiation testing performed as part of the AFCRD Transmutation Fuel Development Program. This document can be considered a supplement to the GNEP TRU Fuel Development and Qualification Plan, and will be revised as necessary to maintain a documented set of fuel testing objectives and requirements consistent with programmatic decisions and advances in technical knowledge.

  5. Dual neutral particle transmutation in CINDER2008

    SciTech Connect

    Martin, W. J.; De Oliveira, C. R. E.

    2012-07-01

    A capability has been built for the CINDER2008 (beta) transmutation code that expands the capability from only neutron induced reactions to photon induced reactions. This allows for two incident neutral particles to cause nuclear transmutation in a given material simultaneously. The CINDER2008 code, a modular rewrite of the CINDER'90 transmutation code from Los Alamos National Laboratory, was modified to allow for the dual sets of physics. A photonuclear cross section and photofission product yield library was also created using ENDF-B/VII data and translated neutron fission product yields. The code and library have been combined to create a unique transmutation code. The scope of use is broad; it is capable of modeling the transmutation caused by photons released from the decay of daughter and fission products as well as transmutation in photon rich environments. A brief code description and a verification and validation of the contributions are given. (authors)

  6. Detailed calculations of minor actinide transmutation in a fast reactor

    SciTech Connect

    Takeda, Toshikazu

    2015-12-31

    The transmutation of minor actinides in a fast reactor is investigated by a new method to investigate the transmutation behavior of individual minor actinides. It is found that Np-237 and Am-241 mainly contributes to the transmutation rate though the transmutation behaviors are very different.

  7. Detailed calculations of minor actinide transmutation in a fast reactor

    NASA Astrophysics Data System (ADS)

    Takeda, Toshikazu

    2015-12-01

    The transmutation of minor actinides in a fast reactor is investigated by a new method to investigate the transmutation behavior of individual minor actinides. It is found that Np-237 and Am-241 mainly contributes to the transmutation rate though the transmutation behaviors are very different.

  8. Transmutation doping of silicon solar cells

    NASA Technical Reports Server (NTRS)

    Wood, R. F.; Westbrook, R. D.; Young, R. T.; Cleland, J. W.

    1977-01-01

    Normal isotopic silicon contains 3.05% of Si-30 which transmutes to P-31 after thermal neutron absorption, with a half-life of 2.6 hours. This reaction is used to introduce extremely uniform concentrations of phosphorus into silicon, thus eliminating the areal and spatial inhomogeneities characteristic of chemical doping. Annealing of the lattice damage in the irradiated silicon does not alter the uniformity of dopant distribution. Transmutation doping also makes it possible to introduce phosphorus into polycrystalline silicon without segregation of the dopant at the grain boundaries. The use of neutron transmutation doped (NTD) silicon in solar cell research and development is discussed.

  9. The Dubna-Mainz-Taipei Dynamical Model for πN Scattering and π Electromagnetic Production

    NASA Astrophysics Data System (ADS)

    Yang, Shin Nan

    Some of the featured results of the Dubna-Mainz-Taipei (DMT) dynamical model for πN scattering and π0 electromagnetic production are summarized. These include results for threshold π0 production, deformation of Δ(1232),and the extracted properties of higher resonances below 2 GeV. The excellent agreement of DMT model's predictions with threshold π0 production data, including the recent precision measurements from MAMI establishes results of DMT model as a benchmark for experimentalists and theorists in dealing with threshold pion production.

  10. Transmutation: The Roots of the Dream.

    ERIC Educational Resources Information Center

    Karpenko, Vladimir

    1995-01-01

    Examines the history of alchemical attempts at transmutation and classifies them by differing approaches and techniques. Traces the development of alchemy in Asia, Europe, and the Middle East, and compares alchemy with craftsmanship. (18 references) (DDR)

  11. Transmutation Theory in the Greek Alchemical Corpus.

    PubMed

    Dufault, Olivier

    2015-08-01

    This paper studies transmutation theory as found in the texts attributed to Zosimus of Panopolis, "the philosopher Synesius," and "the philosopher Olympiodorus of Alexandria." It shows that transmutation theory (i.e. a theory explaining the complete transformation of substances) is mostly absent from the work attributed to these three authors. The text attributed to Synesius describes a gilding process, which is similar to those described by Pliny and Vitruvius. The commentary attributed to Olympiodorus is the only text studied here that describes something similar to a transmutation theory. It is unclear, however, if this was a theory of transmutation or if the writer meant something more like the literal meaning of the word "ekstrophē," a term used to describe the transformation of metals, as the "turning inside-out" of what is hidden in a substance. A similar conception of ekstrophē can be found in the works of Zosimus, who discussed transmutation to make an analogy with self-purification processes, which, from the perspective of his own anthropogony, consisted in the "turning inside-out" of the "inner human" (esō anthrōpos). PMID:26307909

  12. Neutronics, reactor systems and fuels for transmutation

    SciTech Connect

    Warin, D.; Zaetta, A.; Varaine, F.; Grouiller, J. P.; Pillon, S.

    2006-07-01

    The purpose of transmutation is to reduce the mass and the radiotoxicity inventories of Minor Actinides and Long-Lived Fission Products of nuclear waste. In France, the law voted in 1991 for waste management has requested in particular the study of solutions and processes on the subject of transmutation. This review gives conclusions, at the end of the 15 year research period defined by the law, on the scientific and technical feasibility of transmutation based on neutronic aspects, reactor systems and possible fuels, from the CEA point of view. Important results are now available concerning the possibility of significantly reducing the quantity and the radiotoxicity of long-lived waste in association with a sustainable development of nuclear energy. As France has confirmed its long-term approach to nuclear energy, the most effective implementation of (recycling-)transmutation of Minor Actinides other than Plutonium and Uranium depends on the fast neutron GEN IV systems which are designed to recycle and manage their own actinides. The perspective to deploy a first series of such systems around 2040 supports the idea that progress is being made: the nuclear long-term waste would only be made up of Fission Products, whose radio toxicity considerably drops within a few hundred years. Future work will deal with pre industrial demonstrations of transmutation. (authors)

  13. Transmutation Fuel Performance Code Conceptual Design

    SciTech Connect

    Gregory K. Miller; Pavel G. Medvedev

    2007-03-01

    One of the objectives of the Global Nuclear Energy Partnership (GNEP) is to facilitate the licensing and operation of Advanced Recycle Reactors (ARRs) for transmutation of the transuranic elements (TRU) present in spent fuel. A fuel performance code will be an essential element in the licensing process ensuring that behavior of the transmutation fuel elements in the reactor is understood and predictable. Even more important in the near term, a fuel performance code will assist substantially in the fuels research and development, design, irradiation testing and interpretation of the post-irradiation examination results.

  14. Transmutation Fuels Campaign FY-09 Accomplishments Report

    SciTech Connect

    Lori Braase

    2009-09-01

    This report summarizes the fiscal year 2009 (FY-08) accomplishments for the Transmutation Fuels Campaign (TFC). The emphasis is on the accomplishments and relevance of the work. Detailed description of the methods used to achieve the highlighted results and the associated support tasks are not included in this report.

  15. Fission Product Transmutation in Mixed Radiation Fields

    SciTech Connect

    Harmon, Frank; Burgett, Erick; Starovoitova, Valeriia; Tsveretkov, Pavel

    2015-01-15

    Work under this grant addressed a part of the challenge facing the closure of the nuclear fuel cycle; reducing the radiotoxicity of lived fission products (LLFP). It was based on the possibility that partitioning of isotopes and accelerator-based transmutation on particular LLFP combined with geological disposal may lead to an acceptable societal solution to the problem of management. The feasibility of using photonuclear processes based on the excitation of the giant dipole resonance (GDR) by bremsstrahlung radiation as a cost effective transmutation method was accessed. The nuclear reactions of interest: (γ,xn), (n,γ), (γ,p) can be induced by bremsstrahlung radiation produced by high power electron accelerators. The driver of these processes would be an accelerator that produces a high energy and high power electron beam of ~ 100 MeV. The major advantages of such accelerators for this purpose are that they are essentially available “off the shelf” and potentially would be of reasonable cost for this application. Methods were examined that used photo produced neutrons or the bremsstrahlung photons only, or use both photons and neutrons in combination for irradiations of selected LLFP. Extrapolating the results to plausible engineering scale transmuters it was found that the energy cost for 129I and 99Tc transmutation by these methods are about 2 and 4%, respectively, of the energy produced from 1000MWe.

  16. Safety characteristics of potential waste transmutation systems

    SciTech Connect

    Van Tuyle, G.J.

    1993-06-01

    For nuclear waste transmutation to alter significantly the need for geologic disposal of spent fuel from US Light-water reactors (LWRs), about 1.4% of the spent fuel (by mass) must be separated and transmuted. This includes the plutonium, the minor actinides, and four fission products: iodine. technetium, cesium and strontium. Regarding the actinides, fissioning of the plutonium, neptunium, americium, and curium generates a great deal of heat, so much so that most of the plutonium should be used to produce power. However, these actinides have some undesirable neutronic characteristics, and their utilization in reactors or subcritical (proton-accelerator) targets requires either a fast neutronic spectrum or a very high thermal-neutron flux. Transmutation of the fission products is generally by neutron capture, although this is difficult in the case of cesium and strontium. In this paper, various proposed means of transmuting the actinides and fission products are discussed, with the main focus being on the safety characteristics of each approach.

  17. A low aspect ratio tokamak transmutation system

    NASA Astrophysics Data System (ADS)

    Qiu, L. J.; Wu, Y. C.; Xiao, B. J.; Xu, Q.; Huang, Q. Y.; Wu, B.; Chen, Y. X.; Xu, W. N.; Chen, Y. P.; Liu, X. P.

    2000-03-01

    A low aspect ratio tokamak transmutation system is proposed as an alternative application of fusion energy on the basis of a review of previous studies. This system includes: (1) a low aspect ratio tokamak as fusion neutron driver, (2) a radioactivity-clean nuclear power system as blanket, and (3) a novel concept of liquid metal centre conductor post as part of the toroidal field coils. In the conceptual design, a driver of 100 MW fusion power under 1 MW/m2 neutron wall loading can transmute the amount of high level waste (including minor actinides and fission products) produced by ten standard pressurized water reactors of 1 GW electrical power output. Meanwhile, the system can produce tritium on a self-sustaining basis and an output of about 2 GW of electrical energy. After 30 years of operation, the biological hazard potential level of the whole system will decrease by two orders of magnitude.

  18. Statistical transmutation in doped quantum dimer models.

    PubMed

    Lamas, C A; Ralko, A; Cabra, D C; Poilblanc, D; Pujol, P

    2012-07-01

    We prove a "statistical transmutation" symmetry of doped quantum dimer models on the square, triangular, and kagome lattices: the energy spectrum is invariant under a simultaneous change of statistics (i.e., bosonic into fermionic or vice versa) of the holes and of the signs of all the dimer resonance loops. This exact transformation enables us to define the duality equivalence between doped quantum dimer Hamiltonians and provides the analytic framework to analyze dynamical statistical transmutations. We investigate numerically the doping of the triangular quantum dimer model with special focus on the topological Z(2) dimer liquid. Doping leads to four (instead of two for the square lattice) inequivalent families of Hamiltonians. Competition between phase separation, superfluidity, supersolidity, and fermionic phases is investigated in the four families. PMID:23031119

  19. Sphere-Pac Evaluation for Transmutation

    SciTech Connect

    Icenhour, A.S.

    2005-05-19

    The U.S. Department of Energy Advanced Fuel Cycle Initiative (AFCI) is sponsoring a project at Oak Ridge National Laboratory with the objective of conducting the research and development necessary to evaluate the use of sphere-pac transmutation fuel. Sphere-pac fuels were studied extensively in the 1960s and 1970s. More recently, this fuel form is being studied internationally as a potential plutonium-burning fuel. For transmutation fuel, sphere-pac fuels have potential advantages over traditional pellet-type fuels. This report provides a review of development efforts related to the preparation of sphere-pac fuels and their irradiation tests. Based on the results of these tests, comparisons with pellet-type fuels are summarized, the advantages and disadvantages of using sphere-pac fuels are highlighted, and sphere-pac options for the AFCI are recommended. The Oak Ridge National Laboratory development activities are also outlined.

  20. Subcritical transmutation of spent nuclear fuel

    NASA Astrophysics Data System (ADS)

    Sommer, Christopher M.

    2011-07-01

    A series of fuel cycle simulations were performed using CEA's reactor physics code ERANOS 2.0 to analyze the transmutation performance of the Subcritical Advanced Burner Reactor (SABR). SABR is a fusion-fission hybrid reactor that combines the leading sodium cooled fast reactor technology with the leading tokamak plasma technology based on ITER physics. Two general fuel cycles were considered for the SABR system. The first fuel cycle is one in which all of the transuranics from light water reactors are burned in SABR. The second fuel cycle is a minor actinide burning fuel cycle in which all of the minor actinides and some of the plutonium produced in light water reactors are burned in SABR, with the excess plutonium being set aside for starting up fast reactors in the future. The minor actinide burning fuel cycle is being considered in European Scenario Studies. The fuel cycles were evaluated on the basis of TRU/MA transmutation rate, power profile, accumulated radiation damage, and decay heat to the repository. Each of the fuel cycles are compared against each other, and the minor actinide burning fuel cycles are compared against the EFIT transmutation system, and a low conversion ratio fast reactor.

  1. MA transmutation performance in the optimized MYRRHA

    SciTech Connect

    Malambu, E.; Van den Eynde, G.; Fernandez, R.; Baeten, P.; Ait Abderrahim, H.

    2013-07-01

    MYRRHA (multi-purpose hybrid research reactor for high-tech applications) is a multipurpose research facility currently being developed at SCK-CEN. It will be able to work in both critical and subcritical modes and, cooled by lead-bismuth eutectic. In this paper the minor actinides (MA) transmutation capabilities of MYRRHA are investigated. (Pu + Am, U) MOX fuel and (Np + Am + Cm, Pu) Inert Matrix Fuel test samples have been loaded in the central channel of the MYRRHA critical core and have been irradiated during five cycles, each one consisting of 90 days of operation at 100 MWth and 30 days of shutdown. The reactivity worth of the test fuel assembly was about 1.1 dollar. A wide range of burn-up level has been achieved, extending from 42 to 110 MWd/kg HM, the samples with lower MA-to-Pu ratios reaching the highest burn-up. This study has highlighted the importance of the initial MA content, expressed in terms of MA/Pu ratio, on the transmutation rate of MA elements. For (Pu + Am, U) MOX fuel samples, a net build-up of MA is observed when the initial content of MA is very low (here, 1.77 wt% MA/Pu) while a net decrease in MA is observed in the sample with an initial content of 5 wt%. This suggests the existence of some 'equilibrium' initial MA content value beyond which a net transmutation is achievable.

  2. Transmutation Fuel Campaign Description and Status

    SciTech Connect

    Jon Carmack; Kemal O. Pasamehmetoglu

    2008-01-01

    This report contains a technical summary package in response to a Level 2 milestone in the transmutation fuel campaign (TFC) management work-package calling for input to the Secretarial decision. At present, the form of the Secretarial decision package is not fully defined, and it is not clear exactly what will be required from the TFC as a final input. However, it is anticipated that a series oftechnical and programmatic documents will need to be provided in support of a wider encompassing document on GNEP technology development activities. The TFC technical leadership team provides this report as initial input to the secretarial decision package which is being developed by the Technical Integration Office (TIO) in support of Secretarial decision. This report contains a summary of the TFC execution plan with a work breakdown structure, highlevel schedule, major milestones, and summary description of critical activities in support of campaign objectives. Supporting documents referenced in this report but provided under separate cover include: • An updated review of the state-of-the art for transmutation fuel development activities considering national as well as international fuel research and development testing activities. • A definition of the Technology Readiness Level (TRL) used to systematically define and execute the transmutation fuel development activities.

  3. Transmutations of elements under irradiation and its impact on alloys composition

    SciTech Connect

    Gomes, I.C.; Smith, D.L.

    1994-09-01

    This study presents a comparison of nuclear transmutation rates for candidate fusion first wall/blanket structural materials in available fission test reactors with those produced in a typical fusion spectrum. The materials analyzed in this study include a vanadium alloy (V-4Cr-4Ti), a reduced activation martensitic steel (Fe-9Cr-2WVTa), a high conductivity copper alloy (Cu-Cr-Zr), and the SiC compound. The fission irradiation facilities considered include the EBR-II (Experimental Breeder Reactor) fast reactor, and two high flux mixed spectrum reactors, HFIR (High Flux Irradiation Reactor) and SM-3 (Russian reactor). The transmutation and dpa rates that occur in these test reactors are compared with the calculated transmutation and dpa rates characteristic of a D-T fusion first wall spectrum. In general, past work has shown that the displacement damage produced in these fission reactors can be correlated to displacement damage in a fusion spectrum; however, the generation of helium and hydrogen through threshold reactions [(n,x{alpha}) and (n,xp)] are much higher in a fusion spectrum. As shown in this study, the compositional changes for several candidate structural materials exposed to a fast fission reactor spectrum are very low, similar to those for a characteristic fusion spectrum. However, the relatively high thermalized spectrum of a mixed spectrum reactor produces transmutation rates quite different from the ones predicted for a fusion reactor, resulting in substantial differences in the final composition of several candidate alloys after relatively short irradiation time. As examples, the transmutation rates of W, Ta, V, Cu, among others, differ considerably when the irradiation is performed under a mixed spectrum reactor`s and fusion first wall`s spectrum. Fast reactors (EBR-II) provide the only possibility for obtaining high damage rates without producing significant compositional effects in vanadium alloys, ferritic steels and copper alloys.

  4. II. Inhibited Diffusion Driven Surface Transmutations

    NASA Astrophysics Data System (ADS)

    Chubb, Talbot A.

    2006-02-01

    This paper is the second of a set of three papers dealing with the role of coherent partitioning as a common element in Low Energy Nuclear Reactions (LENR), by which is meant cold-fusion related processes. This paper discusses the first step in a sequence of four steps that seem to be necessary to explain Iwamura 2-α-addition surface transmutations. Three concepts are examined: salt-metal interface states, sequential tunneling that transitions D+ ions from localized interstitial to Bloch form, and the general applicability of 2-dimensional vs. 3-dimensional symmetry hosting networks.

  5. The DD Cold Fusion-Transmutation Connection

    NASA Astrophysics Data System (ADS)

    Chubb, Talbot A.

    2005-12-01

    LENR theory must explain dd fusion, alpha-addition transmutations, radiationless nuclear reactions, and three-body nuclear particle reactions. Reaction without radiation requires many-body D Bloch+ periodicity in both location and internal structure dependencies. Electron scattering leads to mixed quantum states. The radiationless dd fusion reaction is 2-D Bloch+ -> {}4 He Bloch2+. Overlap between {}4 He Bloch2+ and surface Cs leads to alpha absorption. In the Iwamura et al. studies active deuterium is created by scattering at diffusion barriers.

  6. Transmutable nanoparticles with reconfigurable surface ligands.

    PubMed

    Kim, Youngeun; Macfarlane, Robert J; Jones, Matthew R; Mirkin, Chad A

    2016-02-01

    Unlike conventional inorganic materials, biological systems are exquisitely adapted to respond to their surroundings. Proteins and other biological molecules can process a complex set of chemical binding events as informational inputs and respond accordingly via a change in structure and function. We applied this principle to the design and synthesis of inorganic materials by preparing nanoparticles with reconfigurable surface ligands, where interparticle bonding can be programmed in response to specific chemical cues in a dynamic manner. As a result, a nascent set of "transmutable nanoparticles" can be driven to crystallize along multiple thermodynamic trajectories, resulting in rational control over the phase and time evolution of nanoparticle-based matter. PMID:26912697

  7. Transmutable nanoparticles with reconfigurable surface ligands

    NASA Astrophysics Data System (ADS)

    Kim, Youngeun; Macfarlane, Robert J.; Jones, Matthew R.; Mirkin, Chad A.

    2016-02-01

    Unlike conventional inorganic materials, biological systems are exquisitely adapted to respond to their surroundings. Proteins and other biological molecules can process a complex set of chemical binding events as informational inputs and respond accordingly via a change in structure and function. We applied this principle to the design and synthesis of inorganic materials by preparing nanoparticles with reconfigurable surface ligands, where interparticle bonding can be programmed in response to specific chemical cues in a dynamic manner. As a result, a nascent set of “transmutable nanoparticles” can be driven to crystallize along multiple thermodynamic trajectories, resulting in rational control over the phase and time evolution of nanoparticle-based matter.

  8. Statistical Transmutation in Floquet Driven Optical Lattices

    NASA Astrophysics Data System (ADS)

    Sedrakyan, Tigran A.; Galitski, Victor M.; Kamenev, Alex

    2015-11-01

    We show that interacting bosons in a periodically driven two dimensional (2D) optical lattice may effectively exhibit fermionic statistics. The phenomenon is similar to the celebrated Tonks-Girardeau regime in 1D. The Floquet band of a driven lattice develops the moat shape, i.e., a minimum along a closed contour in the Brillouin zone. Such degeneracy of the kinetic energy favors fermionic quasiparticles. The statistical transmutation is achieved by the Chern-Simons flux attachment similar to the fractional quantum Hall case. We show that the velocity distribution of the released bosons is a sensitive probe of the fermionic nature of their stationary Floquet state.

  9. Neutron-transmutation-doped germanium bolometers

    NASA Technical Reports Server (NTRS)

    Palaio, N. P.; Rodder, M.; Haller, E. E.; Kreysa, E.

    1983-01-01

    Six slices of ultra-pure germanium were irradiated with thermal neutron fluences between 7.5 x 10 to the 16th and 1.88 x 10 to the 18th per sq cm. After thermal annealing the resistivity was measured down to low temperatures (less than 4.2 K) and found to follow the relationship rho = rho sub 0 exp(Delta/T) in the hopping conduction regime. Also, several junction FETs were tested for noise performance at room temperature and in an insulating housing in a 4.2 K cryostat. These FETs will be used as first stage amplifiers for neutron-transmutation-doped germanium bolometers.

  10. Statistical Transmutation in Floquet Driven Optical Lattices.

    PubMed

    Sedrakyan, Tigran A; Galitski, Victor M; Kamenev, Alex

    2015-11-01

    We show that interacting bosons in a periodically driven two dimensional (2D) optical lattice may effectively exhibit fermionic statistics. The phenomenon is similar to the celebrated Tonks-Girardeau regime in 1D. The Floquet band of a driven lattice develops the moat shape, i.e., a minimum along a closed contour in the Brillouin zone. Such degeneracy of the kinetic energy favors fermionic quasiparticles. The statistical transmutation is achieved by the Chern-Simons flux attachment similar to the fractional quantum Hall case. We show that the velocity distribution of the released bosons is a sensitive probe of the fermionic nature of their stationary Floquet state. PMID:26588392

  11. Investigation of the feasibility of a small scale transmutation device

    NASA Astrophysics Data System (ADS)

    Sit, Roger Carson

    This dissertation presents the design and feasibility of a small-scale, fusion-based transmutation device incorporating a commercially available neutron generator. It also presents the design features necessary to optimize the device and render it practical for the transmutation of selected long-lived fission products and actinides. Four conceptual designs of a transmutation device were used to study the transformation of seven radionuclides: long-lived fission products (Tc-99 and I-129), short-lived fission products (Cs-137 and Sr-90), and selective actinides (Am-241, Pu-238, and Pu-239). These radionuclides were chosen because they are major components of spent nuclear fuel and also because they exist as legacy sources that are being stored pending a decision regarding their ultimate disposition. The four designs include the use of two different devices; a Deuterium-Deuterium (D-D) neutron generator (for one design) and a Deuterium-Tritium (D-T) neutron generator (for three designs) in configurations which provide different neutron energy spectra for targeting the radionuclide for transmutation. Key parameters analyzed include total fluence and flux requirements; transmutation effectiveness measured as irradiation effective half-life; and activation products generated along with their characteristics: activity, dose rate, decay, and ingestion and inhalation radiotoxicity. From this investigation, conclusions were drawn about the feasibility of the device, the design and technology enhancements that would be required to make transmutation practical, the most beneficial design for each radionuclide, the consequence of the transmutation, and radiation protection issues that are important for the conceptual design of the transmutation device. Key conclusions from this investigation include: (1) the transmutation of long-lived fission products and select actinides can be practical using a small-scale, fusion driven transmutation device; (2) the transmutation of long

  12. Transmutation of Matter in Byzantium: The Case of Michael Psellos, the Alchemist

    NASA Astrophysics Data System (ADS)

    Katsiampoura, Gianna

    2008-06-01

    There is thus nothing paradoxical about the inclusion of alchemy in the ensemble of the physical sciences nor in the preoccupation with it on the part of learned men engaged in scientific study. In the context of the Medieval model, where discourse on the physical world was ambiguous, often unclear, and lacking the support of experimental verification, the transmutation of matter, which was the subject of alchemy, even if not attended by a host of occult features, was a process that was thought to have a probable basis in reality. What is interesting in this connection is the utilization of the scientific categories of the day for discussion of transmutation of matter and the attempt to avoid, in most instances in the texts that survive, of methods reminiscent of magic.

  13. Progress of nitride fuel cycle research for transmutation of minor actinides

    SciTech Connect

    Arai, Yasuo; Akabori, Mitsuo; Minato, Kazuo

    2007-07-01

    Recent progress of nitride fuel cycle research for transmutation of MA is summarized. Preparation of MA-bearing nitride pellets, such as (Np,Am)N, (Am,Pu)N and (Np,Pu,Am,Cm)N, was carried out. Irradiation behavior of U-free nitride fuel was investigated by the irradiation test of (Pu,Zr)N and PuN+TiN fuels, in which ZrN and TiN were added as a possible diluent material. Further, pyrochemical process of spent nitride fuel was developed by electrorefining in a molten chloride salt and subsequent re-nitridation of actinides in liquid Cd cathode electro-deposits. Nitride fuel cycle for transmutation of MA has been demonstrated in a laboratory scale by the experimental study with MA and Pu. (authors)

  14. Fermilab Project X nuclear energy application: Accelerator, spallation target and transmutation technology demonstration

    SciTech Connect

    Gohar, Yousry; Johnson, David; Johnson, Todd; Mishra, Shekhar; /Fermilab

    2011-04-01

    The recent paper 'Accelerator and Target Technology for Accelerator Driven Transmutation and Energy Production' and report 'Accelerators for America's Future' have endorsed the idea that the next generation particle accelerators would enable technological breakthrough needed for nuclear energy applications, including transmutation of waste. In the Fall of 2009 Fermilab sponsored a workshop on Application of High Intensity Proton Accelerators to explore in detail the use of the Superconducting Radio Frequency (SRF) accelerator technology for Nuclear Energy Applications. High intensity Continuous Wave (CW) beam from the Superconducting Radio Frequency (SRF) Linac (Project-X) at beam energy between 1-2 GeV will provide an unprecedented experimental and demonstration facility in the United States for much needed nuclear energy Research and Development. We propose to carry out an experimental program to demonstrate the reliability of the accelerator technology, Lead-Bismuth spallation target technology and a transmutation experiment of spent nuclear fuel. We also suggest that this facility could be used for other Nuclear Energy applications.

  15. Critique of rationale for transmutation of nuclear waste

    SciTech Connect

    Smith, C.F.; Cohen, J.J.

    1980-07-01

    It has been suggested that nuclear transmutation could be used in the elimination or reduction of hazards from radioactive wastes. The rationale for this suggestion is the subject of this paper. The objectives of partitioning-transmutation are described. The benefits are evaluated. The author concludes that transmutation would appear at best to offer the opportunity of reducing an already low risk. This would not seem to be justifiable considering the cost. If non-radiological risks are considered, there is a negative total benefit. (DC)

  16. Fast reactor core concepts to improve transmutation efficiency

    SciTech Connect

    Fujimura, Koji; Kawashima, Katsuyuki; Itooka, Satoshi

    2015-12-31

    Fast Reactor (FR) core concepts to improve transmutation efficiency were conducted. A heterogeneous MA loaded core was designed based on the 1000MWe-ABR breakeven core. The heterogeneous MA loaded core with Zr-H loaded moderated targets had a better transmutation performance than the MA homogeneous loaded core. The annular pellet rod design was proposed as one of the possible design options for the MA target. It was shown that using annular pellet MA rods mitigates the self-shielding effect in the moderated target so as to enhance the transmutation rate.

  17. Infrared absorption study of neutron-transmutation-doped germanium

    NASA Technical Reports Server (NTRS)

    Park, I. S.; Haller, E. E.

    1988-01-01

    Using high-resolution far-infrared Fourier transform absorption spectroscopy and Hall effect measurements, the evolution of the shallow acceptor and donor impurity levels in germanium during and after the neutron transmutation doping process was studied. The results show unambiguously that the gallium acceptor level concentration equals the concentration of transmutated Ge-70 atoms during the whole process indicating that neither recoil during transmutation nor gallium-defect complex formation play significant roles. The arsenic donor levels appear at full concentration only after annealing for 1 h at 450 C. It is shown that this is due to donor-radiation-defect complex formation. Again, recoil does not play a significant role.

  18. Fast reactor core concepts to improve transmutation efficiency

    NASA Astrophysics Data System (ADS)

    Fujimura, Koji; Kawashima, Katsuyuki; Itooka, Satoshi

    2015-12-01

    Fast Reactor (FR) core concepts to improve transmutation efficiency were conducted. A heterogeneous MA loaded core was designed based on the 1000MWe-ABR breakeven core. The heterogeneous MA loaded core with Zr-H loaded moderated targets had a better transmutation performance than the MA homogeneous loaded core. The annular pellet rod design was proposed as one of the possible design options for the MA target. It was shown that using annular pellet MA rods mitigates the self-shielding effect in the moderated target so as to enhance the transmutation rate.

  19. Microstructural Characterization of Cast Metallic Transmutation Fuels

    SciTech Connect

    J. I. Cole; D. D. Keiser; J. R. Kennedy

    2007-09-01

    As part of the Global Nuclear Energy Partnership (GNEP) and the Advanced Fuel Cycle Initiative (AFCI), the US Department of Energy (DOE) is participating in an international collaboration to irradiate prototypic actinide-bearing transmutation fuels in the French Phenix fast reactor (FUTURIX-FTA experiment). The INL has contributed to this experiment by fabricating and characterizing two compositions of metallic fuel; a non-fertile 48Pu-12Am-40Zr fuel and a low-fertile 35U-29Pu-4Am-2Np-30Zr fuel for insertion into the reactor. This paper highlights results of the microstructural analysis of these cast fuels, which were reasonably homogeneous in nature, but had several distinct phase constituents. Spatial variations in composition appeared to be more pronounced in the low-fertile fuel when compared to the non-fertile fuel.

  20. Statistical Transmutation in Periodically Driven Optical Lattices

    NASA Astrophysics Data System (ADS)

    Sedrakyan, Tigran; Galitski, Victor; Kamenev, Alex

    We show that interacting bosons in a periodically driven two dimensional (2D) optical lattice may effectively exhibit fermionic statistics. The phenomenon is similar to the celebrated Tonks-Girardeau regime in 1D. The Floquet band of a driven lattice develops the moat shape, i.e., a minimum along a closed contour in the Brillouin zone. Such degeneracy of the kinetic energy favors fermionic quasiparticles. The statistical transmutation is achieved by the Chern-Simons flux attachment similar to the fractional quantum Hall case. We show that the velocity distribution of the released bosons is a sensitive probe of the fermionic nature of their stationary Floquet state. This work was supported by the PFC-JQI (T.S.), USARO and Simons Foundation (V.G.), and DOE Contract DE-FG02-08ER46482 (A.K.).

  1. Spherical tokamak (ST) transmutation of nuclear wastes

    SciTech Connect

    Peng, Y.-K.M.; Galambos, J.D.; Cheng, E.T.; Cerbone, R.J.

    1995-12-31

    The concept for an ST fusion core that drives a He-cooled, actinide-bearing, molten-salt blanket of moderate power density to generate electricity is examined for the first time. The results show that the fusion core is suited for this purpose and require a level of plasma, power density, engineering, and material performances moderate in comparison with what has been considered desirable for fusion-only power plants. The low aspect ratio of ST introduces a relatively thick, diverted scrape-off layer which leads to reduced heat fluxes at the limiter and divertor tiles. The use of a demountable, water-cooled, single-turn copper center leg for the toroidal field coils enables simplifications of the fusion core configuration and improves overall practicality for future power applications. These result in much reduced size and cost of the fusion core for the transmutation power plant relative to an optimized fusion-only fusion core. Surrounded by a separate tritium-breeding zone, the molten-salt blanket concept is in principle less complex and costly than the thermal breeding blankets for fusion. These combine to effect major reductions in the cost and weight of the power core equipment for the transmutation power plant. The minimum cost of electricity for such a power plant is thus reduced from the best fusion-only counterpart by more than 30%, based on consistent but approximate modeling. The key issues, development steps, and the potential value inherent in the ST fusion core in addressing the world needs for nuclear waste energy production are discussed.

  2. Overall assessment of actinide partitioning and transmutation for waste management purposes

    SciTech Connect

    Blomeke, J. O.; Croff, A. G.; Finney, B. C.; Tedder, D. W.

    1980-01-01

    A program to establish the technical feasibility and incentives for partitioning (i.e., recovering) actinides from fuel cycle wastes and then transmuting them in power reactors to shorter-lived or stable nuclides has recently been concluded at the Oak Ridge National Laboratory. The feasibility was established by experimentally investigating the reduction that can be practicably achieved in the actinide content of the wastes sent to a geologic repository, and the incentives for implementing this concept were defined by determining the incremental costs, risks, and benefits. Eight US Department of Energy laboratories and three private companies participated in the program over its 3-year duration. A reference fuel cycle was chosen based on a self-generated plutonium recycle PWR, and chemical flowsheets based on solvent extraction and ion-exchange techniques were generated that have the potential to reduce actinides in fuel fabrication and reprocessing plant wastes to less than 0.25% of those in the spent fuel. Waste treatment facilities utilizing these flowsheets were designed conceptually, and their costs were estimated. Finally, the short-term (contemporary) risks from fuel cycle operations and long-term (future) risks from deep geologic disposal of the wastes were estimated for cases with and without partitioning and transmutation. It was concluded that, while both actinide partitioning from wastes and transmutation in power reactors appear to be feasible using currently identified and studied technology, implementation of this concept cannot be justified because of the small long-term benefits and substantially increased costs of the concept.

  3. The Physics of transmutation systems : system capabilities and performances.

    SciTech Connect

    Finck, P. J.

    2002-08-21

    This document is complementary to a document produced by Prof. Salvatores on ''The Physics of Transmutation in Critical or Subcritical Reactors and the Impact on the Fuel Cycle''. In that document, Salvatores describes the fundamental of transmutation, through basic physics properties and general parametric studies. In the present document we try to go one step further towards practical implementation (while recognizing that the practical issues such as technology development and demonstration, and economics, can only be mentioned in a very superficial manner). Section 1 briefly overviews the possible objectives of transmutation systems, and links these different objectives to possible technological paths. It also describes the overall constraints which have to be considered when developing and implementing transmutation systems. In section 2 we briefly overview the technological constraints which need to be accounted for when designing transmutation systems. In section 3 we attempt to provide a simplified classification of transmutation systems in order to clarify later comparisons. It compares heterogeneous and homogeneous recycle strategies, and single and multi-tier systems. Section 4 presents case analyses for assessing the transmutation performance of various individual systems, starting with LWR's (1. generic results; 2. multirecycle of plutonium; 3. an alternative: transmutation based on a Thorium fuel cycle), followed by Gas-Cooled Reactors (with an emphasis on the ''deep burn'' approach), and followed by Fast Reactors and Accelerator Driven systems (1. generic results; 2. homogeneous recycle of transuranics; 3. practical limit between Fast Reactors and Accelerator Driven Systems) Section 5 summarizes recent results on integrated system performances. It focuses first on interface effects between the two elements of a dual tier system, and then summarizes the major lessons learned from recent global physics studies.

  4. Transmutation of planar media singularities in a conformal cloak.

    PubMed

    Liu, Yichao; Mukhtar, Musawwadah; Ma, Yungui; Ong, C K

    2013-11-01

    Invisibility cloaking based on optical transformation involves materials singularity at the branch cut points. Many interesting optical devices, such as the Eaton lens, also require planar media index singularities in their implementation. We show a method to transmute two singularities simultaneously into harmless topological defects formed by anisotropic permittivity and permeability tensors. Numerical simulation is performed to verify the functionality of the transmuted conformal cloak consisting of two kissing Maxwell fish eyes. PMID:24322926

  5. Crystalline hosts to accommodate the transmutation of Cs and Sr

    NASA Astrophysics Data System (ADS)

    Vance, E. R.; Roy, R.; Pepin, J.; Agrawal, D. K.

    1982-04-01

    Certain deleterious effects on a solid nuclear waste form, though not yet quantitatively defined, could occur due to transmutations such as 137Cs+ yields 137 Ba2+ and 90Sr2+ yields 90Zr4+ (t sub /1/2/ = 30 yr in both cases). The relevant causes of such possible effects are the changes in ionic valence and size. This report explicitly formulates a chemical mitigation strategy: if the transmuting species can be incorporated in a multiple-cation host, in which one of the inert cations is a variable-valence transition metal, the valence change aspect of transmutation can be mitigated by a complementary valence change of the transition metal ion. The present work consisted of chemically simulating the transmutation, the goal being to find a Cs- and Sr-bearing single-phase host that would remain single-phase after the transmutation had occurred. Of several structures tried, perovskite appears to be the most promising, as the A-site can accommodate the approximately 20% size change that occurs when Cs decays to Ba. Ta and Nb were used as the variable-valence ions in the B site. Although not explicity studied here, magnetoplumbite seems likely to accommodate the Cs yields Ba transmutation. The application of the results to unpartitioned and partitioned nuclear wastes is discussed.

  6. The Subcritical Assembly in Dubna (SAD)—Part II: Research program for ADS-demo experiment

    NASA Astrophysics Data System (ADS)

    Gudowski, Waclaw; Shvetsov, Valery; Polanski, Aleksander; Broeders, Cornelis

    2006-06-01

    Subcritical Assembly in Dubna (SAD), a project funded by the International Science and Technology Centre, driven in collaboration with many European partners, may become the first Accelerator Driven Subcritical experiment coupling an existing proton accelerator of 660 MeV with a compact MQX-fuelled subcritical core. The main objective of the SAD experiment is to study physics of Accelerator Driven System ranging from a very deep subcriticality up to keff of 0.98. All experiences with subcriticality monitoring from previous subcritical experiments like MUSE, Yalina and IBR-30 booster mode will be verified in order to select the most reliable subcriticality monitoring technique. Particular attention will be given to validation of the core power-beam current relation. Moreover, some studies have been done to assess possibility of power upgrade for SAD.

  7. Accelerator-driven Transmutation of Waste

    NASA Astrophysics Data System (ADS)

    Venneri, Francesco

    1998-04-01

    Nuclear waste from commercial power plants contains large quantities of plutonium, other fissionable actinides, and long-lived fission products that are potential proliferation concerns and create challenges for the long-term storage. Different strategies for dealing with nuclear waste are being followed by various countries because of their geologic situations and their views on nuclear energy, reprocessing and non-proliferation. The current United States policy is to store unprocessed spent reactor fuel in a geologic repository. Other countries are opting for treatment of nuclear waste, including partial utilization of the fissile material contained in the spent fuel, prior to geologic storage. Long-term uncertainties are hampering the acceptability and eventual licensing of a geologic repository for nuclear spent fuel in the US, and driving up its cost. The greatest concerns are with the potential for radiation release and exposure from the spent fuel for tens of thousands of years and the possible diversion and use of the actinides contained in the waste for weapons construction. Taking advantage of the recent breakthroughs in accelerator technology and of the natural flexibility of subcritical systems, the Accelerator-driven Transmutation of Waste (ATW) concept offers the United States and other countries the possibility to greatly reduce plutonium, higher actinides and environmentally hazardous fission products from the waste stream destined for permanent storage. ATW does not eliminate the need for, but instead enhances the viability of permanent waste repositories. Far from being limited to waste destruction, the ATW concept also brings to the table new technologies that could be relevant for next-generation power producing reactors. In the ATW concept, spent fuel would be shipped to the ATW site where the plutonium, transuranics and selected long-lived fission products would be destroyed by fission or transmutation in their first and only pass through the

  8. Recent development of the CINDER`90 transmutation code and data library for actinide transmutation studies

    SciTech Connect

    Wilson, W.B.; England, T.R.; George, D.C.; Muir, D.W.; Young, P.G.

    1995-09-01

    CINDER`90 is a neutron transmutation code evolved from earlier versions of CINDER and REAC, using the algorithm of CINDER with modifications to accommodate the input of additional constant destruction and production rates associated with reactions outside of the code`s particle or energy domain. In conjunction with other codes simulating the radiation environment, CINDER`90 has been used to describe nuclide inventories in a variety of applications. The library of nuclear data, constantly growing in breadth and quality with international cooperation, now describes 3,400 nuclides in the range 1 {le} Z {le} 103.

  9. Migration and accumulation at dislocations of transmutation helium in austenitic steels upon neutron irradiation

    NASA Astrophysics Data System (ADS)

    Kozlov, A. V.; Portnykh, I. A.

    2016-04-01

    The model of the migration and accumulation at dislocations of transmutation helium and the formation of helium-vacancy pore nuclei in austenitic steels upon neutron irradiation has been proposed. As illustrations of its application, the dependences of the characteristics of pore nuclei on the temperature of neutron irradiation have been calculated. The results of the calculations have been compared with the experimental data in the literature on measuring the characteristics of radiation-induced porosity that arises upon the irradiation of shells of fuel elements of a 16Cr-19Ni-2Mo-2Mn-Si-Ti-Nb-V-B steel in a fast BN600 neutron reactor at different temperatures.

  10. Dual neutral particle induced transmutation in CINDER2008

    NASA Astrophysics Data System (ADS)

    Martin, W. J.; de Oliveira, C. R. E.; Hecht, A. A.

    2014-12-01

    Although nuclear transmutation methods for fission have existed for decades, the focus has been on neutron-induced reactions. Recent novel concepts have sought to use both neutrons and photons for purposes such as active interrogation of cargo to detect the smuggling of highly enriched uranium, a concept that would require modeling the transmutation caused by both incident particles. As photonuclear transmutation has yet to be modeled alongside neutron-induced transmutation in a production code, new methods need to be developed. The CINDER2008 nuclear transmutation code from Los Alamos National Laboratory is extended from neutron applications to dual neutral particle applications, allowing both neutron- and photon-induced reactions for this modeling with a focus on fission. Following standard reaction modeling, the induced fission reaction is understood as a two-part reaction, with an entrance channel to the excited compound nucleus, and an exit channel from the excited compound nucleus to the fission fragmentation. Because photofission yield data-the exit channel from the compound nucleus-are sparse, neutron fission yield data are used in this work. With a different compound nucleus and excitation, the translation to the excited compound state is modified, as appropriate. A verification and validation of these methods and data has been performed. This has shown that the translation of neutron-induced fission product yield sets, and their use in photonuclear applications, is appropriate, and that the code has been extended correctly.

  11. Proposed partitioning and transmutation of long-lived nuclear wastes

    SciTech Connect

    Van Tuyle, G.J. ); Rawlins, J.A. )

    1991-01-01

    A means of transmuting key long-lived nuclear wastes, primarily the minor actinides (Np, Am, Cm) and iodine, using a hybrid proton accelerator and sub-critical lattice, is proposed. By partitioning light water reactor (LWR) spent fuel and by transmuting key elements, such as the plutonium, the minor actinides, and a few of the long-lived fission products, some of the most significant challenges in building a waste repository can be substantially reduced. The proposed machine would transmute the minor actinides and the iodine produced by 75 LWRs, and would generate usable electricity (beyond that required to run the large accelerator) of 850 MW{sub e}. 14 refs., 10 figs.

  12. Fast neutrons for transmutation research within the EFNUDAT project

    SciTech Connect

    Beyer, R.; Junghans, A. R.; Matic, A.; Schilling, K. D.; Schwengner, R.; Wagner, A.; Grosse, E.; Weiss, F. P.

    2009-01-28

    As a Network for research on waste transmutation and on Generation IV nuclear systems within the 6{sup th} EU framework program funds are available for EFNUDAT: European effort to exploit up-to-date neutron beam technology for novel research on the transmutation of radioactive waste. They cover joint research activities on n-beams, targets, data collection and quality assurance as well as transnational access to 10 neutron research facilities. We intend to arouse interest in European research groups to approach the EFNUDAT consortium in case of interest in transmutation related research. As an example we give a brief overview of the new neutron beam of the Strahlungsquelle ELBE at Dresden-Rossendorf.

  13. Nickel Foil as Transmutation Detector for Neutron Fluence Measurements

    NASA Astrophysics Data System (ADS)

    Klupák, Vít; Viererbl, Ladislav; Lahodová, Zdena; Šoltés, Jaroslav; Tomandl, Ivo; Kudějová, Petra

    2016-02-01

    Activation detectors are very often used for determination of the neutron fluence in reactor dosimetry. However, there are few disadvantages concerning these detectors; it is the demand of the knowledge of the irradiation history and a loss of information due to a radioactive decay in time. Transmutation detectors TMD could be a solution in this case. The transmutation detectors are materials in which stable or long-lived nuclides are produced by nuclear reactions with neutrons. From a measurement of concentration of these nuclides, neutron fluence can be evaluated regardless of the cooling time.

  14. Project of the new multifunctional reflectometer GRAINS with horizontal sample plane at the IBR-2M pulsed reactor in Dubna

    NASA Astrophysics Data System (ADS)

    Avdeev, M. V.; Bodnarchuk, V. I.; Lauter-Pasyuk, V. V.; Lauter, H.; Aksenov, V. L.; Yaradaikin, S. P.; Ulyanov, V. A.; Trounov, V. A.; Kalinin, S. I.

    2010-11-01

    The new multifunctional reflectometer GRAINS is under construction at the modernized high flux IBR-2 pulsed reactor (IBR-2M) of the FLNP JINR (Dubna, Russia). The principal feature of this reflectometer, the horizontal sample plane (or vertical scattering plane), enables the study of liquid-containing interfaces. The reflectometer will operate in the time-of-flight regime with constant sample illumination during measurements. The important advantage is the constant angular resolution with unvaried background. The additional modes of the GRAINS reflectometer comprise (1) off-specular scattering and GISANS, which are measured simultaneously in the TOF regime at a 2D position-sensitive detector; (2) angular encoding in the horizontal plane, which is provided by a Larmor precession region limited by current sheets in front of the sample; (3) 3D polarimetry in reflection, which is provided by a Larmor precession region around the sample position. The design of the reflectometer is optimised to take better advantage of an exceptionally broad wavelength band of the new cold moderator at the IBR-2M. The set-up will open up principally new possibilities for investigations in the field of interface nano-science at the IBR-2M reactor.

  15. Transmutation analysis of realistic low-activation steels for magnetic fusion reactors and IFMIF

    SciTech Connect

    Cabellos, O; Sanz, J; Garc?a-Herranz, N; D?az, S; Reyes, S; Piedloup, S

    2005-11-22

    A comprehensive transmutation study for steels considered in the selection of structural materials for magnetic and inertial fusion reactors has been performed in the IFMIF neutron irradiation scenario, as well as in the ITER and DEMO ones for comparison purposes. An element-by-element transmutation approach is used in the study, addressing the generation of: (1) H and He and (2) solid transmutants. The IEAF-2001 activation library and the activation code ACAB were applied to the IFMIF transmutation analysis, after proving the applicability of ACAB for transmutation calculations of this kind of intermediate energy systems.

  16. Promises and Challenges of Thorium Implementation for Transuranic Transmutation - 13550

    SciTech Connect

    Franceschini, F.; Lahoda, E.; Wenner, M.; Lindley, B.; Fiorina, C.; Phillips, C.

    2013-07-01

    This paper focuses on the challenges of implementing a thorium fuel cycle for recycle and transmutation of long-lived actinide components from used nuclear fuel. A multi-stage reactor system is proposed; the first stage consists of current UO{sub 2} once-through LWRs supplying transuranic isotopes that are continuously recycled and burned in second stage reactors in either a uranium (U) or thorium (Th) carrier. The second stage reactors considered for the analysis are Reduced Moderation Pressurized Water Reactors (RMPWRs), reconfigured from current PWR core designs, and Fast Reactors (FRs) with a burner core design. While both RMPWRs and FRs can in principle be employed, each reactor and associated technology has pros and cons. FRs have unmatched flexibility and transmutation efficiency. RMPWRs have higher fuel manufacturing and reprocessing requirements, but may represent a cheaper solution and the opportunity for a shorter time to licensing and deployment. All options require substantial developments in manufacturing, due to the high radiation field, and reprocessing, due to the very high actinide recovery ratio to elicit the claimed radiotoxicity reduction. Th reduces the number of transmutation reactors, and is required to enable a viable RMPWR design, but presents additional challenges on manufacturing and reprocessing. The tradeoff between the various options does not make the choice obvious. Moreover, without an overarching supporting policy in place, the costly and challenging technologies required inherently discourage industrialization of any transmutation scheme, regardless of the adoption of U or Th. (authors)

  17. Characterization of nuclear transmutations in materials irradiated test facilities

    SciTech Connect

    Gomes, I.C.; Smith, D.L.

    1994-05-01

    This study presents a comparison of nuclear transmutation rates for candidate fusion first wall/blanket structural materials in available, fission test reactors with those produced in a typical fusion spectrum. The materials analyzed in this study include a vanadium alloy (V-4Cr-4Ti), a reduced activation martensitic steel (Fe-9Cr-2WVTa), a high conductivity copper alloy (Cu-Cr-Zr), and the SiC compound. The fission irradiation facilities considered include the EBR-II fast reactor, and two high flux mixed spectrum reactors, HFIR (High Flux Irradiation Reactor) and SM-3 (Russian reactor). The transmutation and dpa rates that occur in these test reactors are compared with the calculated transmutation and dpa rates characteristic of a D-T fusion first wall spectrum. In general, past work has shown that the displacement damage produced in these fission reactors can be correlated to displacement damage in a fusion spectrum; however, the generation of helium and hydrogen through threshold reactions [(n,x,{alpha}) and (n,xp)] are much higher in a fusion spectrum. As shown in this study, the compositional changes for several candidate structural materials exposed to a fast fission reactor spectrum are very low, similar to those for a characteristic fusion spectrum. However, the relatively high thermalized spectrum of a mixed spectrum reactor produces transmutation rates quite different from the ones predicted for a fusion reactor, resulting in substantial differences in the final composition of several candidate alloys after relatively short irradiation time.

  18. Method and apparatus for transmutation of atomic nuclei

    DOEpatents

    Maenchen, J.E.; Ruiz, C.L.

    1998-06-09

    Insuring a constant supply of radioisotopes is of great importance to medicine and industry. This invention addresses this problem, and helps to solve it by introducing a new apparatus for transmutation of isotopes which enables swift and flexible production on demand. 9 figs.

  19. Method and apparatus for transmutation of atomic nuclei

    DOEpatents

    Maenchen, John Eric; Ruiz, Carlos Leon

    1998-01-01

    Insuring a constant supply of radioisotopes is of great importance to medicine and industry. This invention addresses this problem, and helps to solve it by introducing a new apparatus for transmutation of isotopes which enables swift and flexible production on demand.

  20. Method and apparatus for transmutation of atomic nuclei

    DOEpatents

    Maenchen, J.E.; Ruiz, C.L.

    1998-12-08

    Insuring a constant supply of radioisotopes is of great importance to medicine and industry. This invention addresses this problem, and helps to solve it by introducing a new apparatus for transmutation of isotopes which enables swift and flexible production on demand. 9 figs.

  1. Accelerator-driven transmutation of spent fuel elements

    DOEpatents

    Venneri, Francesco; Williamson, Mark A.; Li, Ning

    2002-01-01

    An apparatus and method is described for transmuting higher actinides, plutonium and selected fission products in a liquid-fuel subcritical assembly. Uranium may also be enriched, thereby providing new fuel for use in conventional nuclear power plants. An accelerator provides the additional neutrons required to perform the processes. The size of the accelerator needed to complete fuel cycle closure depends on the neutron efficiency of the supported reactors and on the neutron spectrum of the actinide transmutation apparatus. Treatment of spent fuel from light water reactors (LWRs) using uranium-based fuel will require the largest accelerator power, whereas neutron-efficient high temperature gas reactors (HTGRs) or CANDU reactors will require the smallest accelerator power, especially if thorium is introduced into the newly generated fuel according to the teachings of the present invention. Fast spectrum actinide transmutation apparatus (based on liquid-metal fuel) will take full advantage of the accelerator-produced source neutrons and provide maximum utilization of the actinide-generated fission neutrons. However, near-thermal transmutation apparatus will require lower standing

  2. DETERMINATION OF TRANSMUTATION EFFECTS IN CRYSTALLINE WASTE FORMS

    EPA Science Inventory

    The objective of this study is to characterize the effects of transmutation in a candidatewaste form for 137Cs by investigating samples of a cesium aluminosilicate mineral,pollucite, that have undergone "natural" decay of the Cs under ambient temperaturewhile isolated from int...

  3. Analysis of the Gas Core Actinide Transmutation Reactor (GCATR)

    NASA Technical Reports Server (NTRS)

    Clement, J. D.; Rust, J. H.

    1977-01-01

    Design power plant studies were carried out for two applications of the plasma core reactor: (1) As a breeder reactor, (2) As a reactor able to transmute actinides effectively. In addition to the above applications the reactor produced electrical power with a high efficiency. A reactor subsystem was designed for each of the two applications. For the breeder reactor, neutronics calculations were carried out for a U-233 plasma core with a molten salt breeding blanket. A reactor was designed with a low critical mass (less than a few hundred kilograms U-233) and a breeding ratio of 1.01. The plasma core actinide transmutation reactor was designed to transmute the nuclear waste from conventional LWR's. The spent fuel is reprocessed during which 100% of Np, Am, Cm, and higher actinides are separated from the other components. These actinides are then manufactured as oxides into zirconium clad fuel rods and charged as fuel assemblies in the reflector region of the plasma core actinide transmutation reactor. In the equilibrium cycle, about 7% of the actinides are directly fissioned away, while about 31% are removed by reprocessing.

  4. Application of gaseous core reactors for transmutation of nuclear waste

    NASA Technical Reports Server (NTRS)

    Schnitzler, B. G.; Paternoster, R. R.; Schneider, R. T.

    1976-01-01

    An acceptable management scheme for high-level radioactive waste is vital to the nuclear industry. The hazard potential of the trans-uranic actinides and of key fission products is high due to their nuclear activity and/or chemical toxicity. Of particular concern are the very long-lived nuclides whose hazard potential remains high for hundreds of thousands of years. Neutron induced transmutation offers a promising technique for the treatment of problem wastes. Transmutation is unique as a waste management scheme in that it offers the potential for "destruction" of the hazardous nuclides by conversion to non-hazardous or more manageable nuclides. The transmutation potential of a thermal spectrum uranium hexafluoride fueled cavity reactor was examined. Initial studies focused on a heavy water moderated cavity reactor fueled with 5% enriched U-235-F6 and operating with an average thermal flux of 6 times 10 to the 14th power neutrons/sq cm-sec. The isotopes considered for transmutation were I-129, Am-241, Am-242m, Am-243, Cm-243, Cm-244, Cm-245, and Cm-246.

  5. Optimization of accelerator-driven technology for LWR waste transmutation

    SciTech Connect

    Bowman, C.D.

    1996-12-31

    The role of accelerator-driven transmutation technology is examined in the context of the destruction of actinide waste from commercial light water reactors. It is pointed out that the commercial plutonium is much easier to use for entry-level nuclear weapons than weapons plutonium. Since commercial plutonium is easier to use, since there is very much more of it already, and since it is growing rapidly, the permanent disposition of commercial plutonium is an issue of greater importance than weapons plutonium. The minor actinides inventory, which may be influenced by transmutation, is compared in terms of nuclear properties with commercial and weapons plutonium and for possible utility as weapons material. Fast and thermal spectrum systems are compared as means for destruction of plutonium and the minor actinides. it is shown that the equilibrium fast spectrum actinide inventory is about 100 times larger than for thermal spectrum systems, and that there is about 100 times more weapons-usable material in the fast spectrum system inventory compared to the thermal spectrum system. Finally it is shown that the accelerator size for transmutation can be substantially reduced by design which uses the accelerator-produced neutrons only to initiate the unsustained fission chains characteristic of the subcritical system. The analysis argues for devoting primary attention to the development of thermal spectrum transmutation technology. A thermal spectrum transmuter operating at a fission power of 750-MWth fission power, which is sufficient to destroy the actinide waste from one 3,000-MWth light water reactor, may be driven by a proton beam of 1 GeV energy and a current of 7 mA. This accelerator is within the range of realizable cyclotron technology and is also near the size contemplated for the next generation spallation neutron source under consideration by the US, Europe, and Japan.

  6. Radioactive waste from transmutation of technetium: a model for anticipating characteristics of high level waste from transmutation

    SciTech Connect

    Seitz, M.G.

    2007-07-01

    At this early stage in the conceptualization of fuel treatment and radioisotope transmutation for the disposition of nuclear wastes, it is possible to anticipate some characteristics of the waste stream resulting from the deployment of advanced technologies. Fission products and actinides cannot be completely destroyed by transmutation even with continuous purification and recycle. This is demonstrated for technetium in this analysis, but is true for all radioisotopes. Also, some of the reaction products are themselves long-lived radioactive isotopes. The purification and recycle steps produce nuclear wastes that must be planned for geologic disposal. Five radioisotopes have been identified to be produced in abundance by transmutation of technetium using fast neutrons. Four of these isotopes may be more benign than the original technetium-99 because of their longer half lives. However, one isotope, molybdenum-93 with a half life of four thousand years, may be troublesome. All of the isotopes arising from the transmutation process that end up in high level waste must be examined in terms of their behavior in geologic disposal. In selecting goals for chemical separations, the technologists must consider the entire cycle of separation and transmutation before applying the performance expected in a single separation to implications concerning a repository. A separation efficiency of 0.95 can translate into the disposal of as much as 30 to 60 percent of the technetium in the repository if down stream losses are not controlled. In this case, the treatment may have little impact on anticipated off site radiation from technetium. The destruction of technetium through continuous recycle requires the cost of increased neutron dose and increased space in reactors that must be considered in design of fuel treatment systems. (authors)

  7. Target dependence of clan model parameters at Dubna energy-chaotic pion production

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, Swarnapratim; Haiduc, Maria; Neagu, Alina Tania; Firu, Elena

    2013-02-01

    A detailed study of clan model parameters and their target dependence has been carried out in the light of void probability scaling for heavy (AgBr) and light (CNO) groups of targets present in the nuclear emulsion using 22Ne (at an incident momentum of 4.1 GeV/c), 28Si (at an incident momentum of 4.5 GeV/c), 16O (at an incident momentum of 4.5 GeV/c) and 32S (at an incident momentum of 4.5 GeV/c) projectiles. The variation of scaled rap-gap probability with the single moment combination has been studied for all of the interactions. The experimental points are found to lie approximately on the NBD curve for all of the interactions, indicating a scaling behavior. According to the two-source model of particle production, in the case of 32S-AgBr interactions at 4.5 GeV/c, the pion production mechanism has been found to be almost chaotic. On the contrary, for all of the other interactions at 4.1-4.5 GeV/c, pion production is predominantly chaotic. Average clan multiplicities (\\overline N) for all of the interactions are found to increase with the increase in the pseudo-rapidity interval Δη. The values of \\overline N for the AgBr target are larger than those for the CNO target. The average number of particles per clan (\\overline n_c) increases initially with the increase in pseudo-rapidity interval. An approximate saturation of the values of \\overline n_c is observed for 22Ne and 16O projectiles around Δη = 6. With the increase in projectile size, the saturation of \\overline n_c seems to be wiped out. It can also be observed from the tables that for a particular target the average number of particles per clan (\\overline n_c) increases with the increase in the size of the projectile nucleus. A comparison with the results of the SPS data has also been presented.

  8. Definition of Technology Readiness Levels for Transmutation Fuel Development

    SciTech Connect

    Jon Carmack; Kemal O. Pasamehmetoglu

    2008-01-01

    To quantitatively assess the maturity of a given technology, the Technology Readiness Level (TRL) process is used. The TRL process has been developed and successfully used by the Department of Defense (DOD) for development and deployment of new technology and systems for defense applications. In addition, NASA has also successfully used the TRL process to develop and deploy new systems for space applications. Transmutation fuel development is a critical technology needed for closing the nuclear fuel cycle. Because the deployment of a new nuclear fuel forms requires a lengthy and expensive research, development, and demonstration program, applying the TRL concept to the transmutation fuel development program is very useful as a management and tracking tool. This report provides definition of the technology readiness level assessment process as defined for use in assessing nuclear fuel technology development for the Transuranic Fuel Development Campaign.

  9. Development of neutron-transmutation-doped germanium bolometer material

    SciTech Connect

    Palaio, N.P.

    1983-08-01

    The behavior of lattice defects generated as a result of the neutron-transmutation-doping of germanium was studied as a function of annealing conditions using deep level transient spectroscopy (DLTS) and mobility measurements. DLTS and variable temperature Hall effect were also used to measure the activation of dopant impurities formed during the transmutation process. In additioon, a semi-automated method of attaching wires on to small chips of germanium (< 1 mm/sup 3/) for the fabrication of infrared detecting bolometers was developed. Finally, several different types of junction field effect transistors were tested for noise at room and low temperature (approx. 80 K) in order to find the optimum device available for first stage electronics in the bolometer signal amplification circuit.

  10. Neutron transmutation doped silicon — technological and economic aspects

    NASA Astrophysics Data System (ADS)

    von Ammon, W.

    1992-01-01

    Neutron transmutation doping of silicon was commercially introduced in 1973. The advent of this technique was a great step ahead in the development of high power semiconductor devices as it allows tight resistivity tolerances and excellent homogeneity of the silicon base material. These properties are indispensible for the functioning of today's power devices and cannot be provided by conventional doping methods. Neutron transmutation doping has become a mature and well established technology and a substantial source of income for numerous research reactors throughout the world. First, this paper will present a brief historical review of the early days of silicon irradiation. Then, the ingot preparation and the irradiation procedure as well as the subsequent ingot annealing and characterization are described. Furthermore, problems related to the irradiation damage of the silicon lattice are discussed. Finally, the market development and economic aspects of NTD silicon are considered and an outlook is given on the available irradiation capacity in the future.

  11. Radiation and transmutation effects relevant to solid nuclear waste forms

    SciTech Connect

    Vance, E.R.; Roy, R.; Pillay, K.K.S.

    1981-03-15

    Radiation effects in insulating solids are discussed in a general way as an introduction to the quite sparse published work on radiation effects in candidate nuclear waste forms other than glasses. Likely effects of transmutation in crystals and the chemical mitigation strategy are discussed. It seems probable that radiation effects in solidified HLW will not be serious if the actinides can be wholly incorporated in such radiation-resistant phases as monazite or uraninite.

  12. Actinide partitioning-transmutation program final report. I. Overall assessment

    SciTech Connect

    Croff, A.G.; Blomeke, J.O.; Finney, B.C.

    1980-06-01

    This report is concerned with an overall assessment of the feasibility of and incentives for partitioning (recovering) long-lived nuclides from fuel reprocessing and fuel refabrication plant radioactive wastes and transmuting them to shorter-lived or stable nuclides by neutron irradiation. The principal class of nuclides considered is the actinides, although a brief analysis is given of the partitioning and transmutation (P-T) of /sup 99/Tc and /sup 129/I. The results obtained in this program permit us to make a comparison of the impacts of waste management with and without actinide recovery and transmutation. Three major conclusions concerning technical feasibility can be drawn from the assessment: (1) actinide P-T is feasible, subject to the acceptability of fuels containing recycle actinides; (2) technetium P-T is feasible if satisfactory partitioning processes can be developed and satisfactory fuels identified (no studies have been made in this area); and (3) iodine P-T is marginally feasible at best because of the low transmutation rates, the high volatility, and the corrosiveness of iodine and iodine compounds. It was concluded on the basis of a very conservative repository risk analysis that there are no safety or cost incentives for actinide P-T. In fact, if nonradiological risks are included, the short-term risks of P-T exceed the long-term benefits integrated over a period of 1 million years. Incentives for technetium and iodine P-T exist only if extremely conservative long-term risk analyses are used. Further RD and D in support of P-T is not warranted.

  13. Transmutation of Mo, Re, W, Hf, and V in various irradiation test facilities and STARFIRE

    NASA Astrophysics Data System (ADS)

    Greenwood, L. R.; Garner, F. A.

    1994-09-01

    With the exception of V and Cu alloys, the formation of solid transmutants has not been thought to play a large role in the response of metals to irradiation. For a number of refractory elements, however, it appears that very large levels of solid transmutation can occur both in fission and fusion spectra. The phase stability and other properties of alloys can be strong functions of the changing composition. The spectral sensitivity of transmutation also poses some difficulty in correlating data from various neutron spectra. Transmutation of Mo, Re, W, Hf and V have been calculated for the Fast Flux Test Facility (FFTF), the High Flux Isotope Reactor (HFIR), and the STARFIRE fusion reactor. Results show that Re and W undergo sizeable transmutation in these spectra, and may limit the use of these elements in fusion reactor materials. Vanadium and hafnium have high transmutation rates in HFIR and may require spectral tailoring.

  14. Transmutation of nuclear waste with a low-aspect-ratio tokamak neutron source

    NASA Astrophysics Data System (ADS)

    Hong, Bong Guen; Moon, Se Youn

    2014-10-01

    The transmutation characteristics of transuranics (TRUs) in a transmutation reactor based on a LAR (Low-aspect-ratio) tokamak as a neutron source are investigated. The optimum radial build of a transmutation reactor is found by using a coupled analysis of the tokamak systems and the neutron transport. The dependences of the transmutation characteristics on the aspect ratio A in the range of 1.5 to 2.5 and on the fusion power in the range of 150 to 500 MW are investigated. An equilibrium fuel cycle is developed for effective transmutation, and show that with one unit of the transmutation reactor based on the LAR tokamak producing fusion power in the range of a few hundred MWs, up to 3 PWRs (1.0 GWe capacity) can be supported with a burn-up fraction larger than 50%.

  15. The status of nuclear data for transmutation calculations

    SciTech Connect

    Wilson, W.B.; England, T.R.; MacFarlane, R.E.; Muir, D.W.; Young, P.G.

    1995-12-01

    At this point, the accurate description of transmutation products in a radiation environment is more a nuclear data problem than a code development effort. We have used versions of the CINDER code for over three decades to describe the transmutation of nuclear reactor fuels in radiation environments. The need for the accurate description of reactor neutron-absorption, decay-power, and decay-spectra properties have driven many AEC, ERDA, and DOE supported nuclear data development efforts in this period. The level of cross-section, decay, and fission-yield data has evolved from rudimentary to a comprehensive ENDF/B-VI library permitting great precision in reactor calculations. The precision of the data supporting reactor simulations provides a sturdy foundation for the data base required for the wide range of transmutation problems currently studied. However, such reactor problems are typically limited to neutron energies below 10 MeV or so; reaction and decay data are required for actinides of, say, 90 {le} Z {le} 96 neutron-rich fission products of 22 {le} Z {le} 72. The expansion into reactor structural materials and fusion systems extends these ranges in energy and Z somewhat. The library of nuclear data, constantly growing in breadth and quality with international cooperation, is now described in the following table.

  16. Transmutation of Nuclear Waste and the future MYRRHA Demonstrator

    NASA Astrophysics Data System (ADS)

    Mueller, Alex C.

    2013-03-01

    While a considerable and world-wide growth of the nuclear share in the global energy mix is desirable for many reasons, there are also, in particular in the "old world" major objections. These are both concerns about safety, in particular in the wake of the Fukushima nuclear accident and concerns about the long-term burden that is constituted by the radiotoxic waste from the spent fuel. With regard to the second topic, the present contribution will outline the concept of Partitioning & Transmutation (P&T), as scientific and technological answer. Deployment of P&T may use dedicated "Transmuter" or "Burner" reactors, using a fast neutron spectrum. For the transmutation of waste with a large content (up to 50%) of (very long-lived) Minor Actinides, a sub-critical reactor, using an external neutron source is a most attractive solution. It is constituted by coupling a proton accelerator, a spallation target and a subcritical core. This promising new technology is named ADS, for accelerator-driven system. The present paper aims at a short introduction into the field that has been characterized by a high collaborative activity during the last decade in Europe, in order to focus, in its later part, on the MYRRHA project as the European ADS technology demonstrator.

  17. Gas core reactors for actinide transmutation and breeder applications

    NASA Technical Reports Server (NTRS)

    Clement, J. D.; Rust, J. H.

    1978-01-01

    This work consists of design power plant studies for four types of reactor systems: uranium plasma core breeder, uranium plasma core actinide transmuter, UF6 breeder and UF6 actinide transmuter. The plasma core systems can be coupled to MHD generators to obtain high efficiency electrical power generation. A 1074 MWt UF6 breeder reactor was designed with a breeding ratio of 1.002 to guard against diversion of fuel. Using molten salt technology and a superheated steam cycle, an efficiency of 39.2% was obtained for the plant and the U233 inventory in the core and heat exchangers was limited to 105 Kg. It was found that the UF6 reactor can produce high fluxes (10 to the 14th power n/sq cm-sec) necessary for efficient burnup of actinide. However, the buildup of fissile isotopes posed severe heat transfer problems. Therefore, the flux in the actinide region must be decreased with time. Consequently, only beginning-of-life conditions were considered for the power plant design. A 577 MWt UF6 actinide transmutation reactor power plant was designed to operate with 39.3% efficiency and 102 Kg of U233 in the core and heat exchanger for beginning-of-life conditions.

  18. New elements from Dubna

    NASA Astrophysics Data System (ADS)

    Oganessian, Yu. Ts.; Utyonkov, V. K.; Lobanov, Yu. V.; Abdullin, F. Sh.; Polyakov, A. N.; Shirokovsky, I. V.; Tsyganov, Yu. S.; Gulbekian, G. G.; Bogomolov, S. L.; Gikal, B. N.; Mezentsev, A. N.; Iliev, S.; Subbotin, V. G.; Sukhov, A. M.; Voinov, A. A.; Buklanov, G. V.; Subotic, K.; Zagrebaev, V. I.; Itkis, M. G.; Patin, J. B.; Moody, K. J.; Wild, J. F.; Stoyer, M. A.; Stoyer, N. J.; Shaughnessy, D. A.; Kenneally, J. M.; Wilk, P. A.; Lougheed, R. W.

    2005-09-01

    We have studied the dependence of the production cross-sections of the isotopes 282, 283112 and 286-288114 on the excitation energy of the compound nuclei 286112 and 290114. The maximum cross-sections of the xn-evaporation channels for the reaction 238U(48Ca, xn)286-x112 were measured to be: σ3n = 2.5+1.8-1.1pb and σ4n = 0.6+1.6-0.5pb; for the reaction 242Pu(48Ca, xn)290-x114: σ2n ˜ 0.5pb, σ3n = 3.6+3.4-1.7pb and σ4n = 4.5+3.6-1.9pb. In the reaction 233U(48Ca, 2-4n)277-279112 we measured an upper cross-section limit of σxn≤0.6pb. An increase of σER in the reactions of actinide targets with 48Ca can be due to the expected increase of the survivability of the excited compound nucleus upon closer approach to the closed neutron shell N = 184. The observed nuclear decay properties of the nuclides with Z = 104-118 are compared with theoretical nuclear mass calculations and the systematic trends of α-decay properties. As a whole, they give a consistent pattern of decay of the 18 even-Z neutron-rich nuclides with Z = 104-118 and N = 163-177.

  19. Radiotoxicity of Actinides During Transmutation in Final Stage of Atomic Power

    SciTech Connect

    Gerasimov, Aleksander S.; Bergelson, Boris R.; Myrtsymova, Lidia A.; Tikhomirov, Georgy V.

    2002-07-01

    Characteristics of a transmutation mode in final stage of atomic power are analyzed. In this stage, transmutation of actinides accumulated in transmutation reactors is performed without feed by actinides from other reactors. The radiotoxicity during first 20 years of transmutation is caused mainly by {sup 244}Cm. During following period of time, {sup 252}Cf is main nuclide. Contribution of {sup 246}Cm and {sup 250}Cf is 5-7 times less than that of {sup 252}Cf. During 50 years of a transmutation, the total radiotoxicity falls by 50 times. Long-lived radiotoxicity decreases slowly. During the period between T=50 years and T=100 years, long-lived radiotoxicity falls by 3.7 times. For each following 50 years after this period, long-lived radiotoxicity falls by 3.2 times. These results corresponding to neutron flux density 10{sup 14} neutr/(cm{sup 2}s) in transmutation reactor demonstrate that the final stage of a transmutation should be performed with use of high flux transmutation facilities which provide shorter time of transmutation. (authors)

  20. Anyons and transmutation of statistics via a vacuum-induced Berry phase

    SciTech Connect

    Serra, Roberto M.; Vedral, Vlatko; Carollo, Angelo; Santos, Marcelo Franca

    2004-10-01

    We show that bosonic fields may present anyonic behavior when interacting with a fermion in a Jaynes-Cummings-like model. The proposal is accomplished via the interaction of a two-level system with two quantized modes of a harmonic oscillator; under suitable conditions, the system acquires a fractional geometric phase. A crucial role is played by the entanglement of the system eigenstates, which provides a two-dimensional confinement in the effective evolution of the system, leading to the anyonic behavior. For a particular choice of parameters, we show that it is possible to transmute the statistics of the system continually from fermions to bosons. We also present an experimental proposal, in an ion-trap setup, in which fractional statistical features can be generated, controlled, and measured.

  1. Coherent transmutation of electrons into fractionalized anyons.

    PubMed

    Barkeshli, Maissam; Berg, Erez; Kivelson, Steven

    2014-11-01

    Electrons have three quantized properties-charge, spin, and Fermi statistics-that are directly responsible for a vast array of phenomena. Here we show how these properties can be coherently and dynamically stripped from the electron as it enters a certain exotic state of matter known as a quantum spin liquid (QSL). In a QSL, electron spins collectively form a highly entangled quantum state that gives rise to the fractionalization of spin, charge, and statistics. We show that certain QSLs host distinct, topologically robust boundary types, some of which allow the electron to coherently enter the QSL as a fractionalized quasi-particle, leaving its spin, charge, or statistics behind. We use these ideas to propose a number of universal, conclusive experimental signatures that would establish fractionalization in QSLs. PMID:25378617

  2. IAEA activities in the area of partitioning and transmutation

    NASA Astrophysics Data System (ADS)

    Stanculescu, Alexander

    2006-06-01

    Four major challenges are facing the long-term development of nuclear energy: improvement of the economic competitiveness, meeting increasingly stringent safety requirements, adhering to the criteria of sustainable development, and public acceptance. Meeting the sustainability criteria is the driving force behind the topic of this paper. In this context, sustainability has two aspects: natural resources and waste management. IAEA's activities in the area of Partitioning and Transmutation (P&T) are mostly in response to the latter. While not involving the large quantities of gaseous products and toxic solid wastes associated with fossil fuels, radioactive waste disposal is today's dominant public acceptance issue. In fact, small waste quantities permit a rigorous confinement strategy, and mined geological disposal is the strategy followed by some countries. Nevertheless, political opposition arguing that this does not yet constitute a safe disposal technology has largely stalled these efforts. One of the primary reasons cited is the long life of many of the radioisotopes generated from fission. This concern has led to increased R&D efforts to develop a technology aimed at reducing the amount and radio-toxicity of long-lived radioactive waste through transmutation in fission reactors or sub-critical systems. In the frame of the Project on Technology Advances in Fast Reactors and Accelerator-Driven Systems (ADS), the IAEA initiated a number of activities on utilization of plutonium and transmutation of long-lived radioactive waste, ADS, and deuterium-tritium plasma-driven sub-critical systems. The paper presents past accomplishments, current status and planned activities of this IAEA project.

  3. Muonic alchemy: Transmuting elements with the inclusion of negative muons

    NASA Astrophysics Data System (ADS)

    Moncada, Félix; Cruz, Daniel; Reyes, Andrés

    2012-06-01

    In this Letter we present a theoretical study of atoms in which one electron has been replaced by a negative muon. We have treated these muonic systems with the Any Particle Molecular Orbital (APMO) method. A comparison between the electronic and muonic radial distributions revealed that muons are much more localized than electrons. Therefore, the muonic cloud is screening effectively one positive charge of the nucleus. Our results have revealed that by replacing an electron in an atom by a muon there is a transmutation of the electronic properties of that atom to those of the element with atomic number Z - 1.

  4. Cu-Doping of ZnO by Nuclear Transmutation

    SciTech Connect

    Selim, F. A.; Tarun, M. C.; Wall, D. E.; Boatner, Lynn A; McCluskey, M. D.

    2011-01-01

    Zinc oxide single crystals were doped with copper acceptors by means of the nuclear transmutation doping (NTD) method, which gives highly uniform dopant distributions and has a much higher probability of controlling the dopant locations in the lattice. The Cu doping was confirmed by the infrared absorption signature of Cu2+ at 5780 cm-1. Hall-effect measurements were performed to study the effect of CuZn on the electrical properties of ZnO. These measurements indicated that the Cu acceptor level lies 0.126 eV below the conduction-band minimum.

  5. Carrier doping into boron nanobelts by neutron transmutation

    SciTech Connect

    Kirihara, Kazuhiro; Shimizu, Yoshiki; Sasaki, Takeshi; Koshizaki, Naoto; Yamada, Yoichi; Esaka, Fumitaka; Yamamoto, Hiroyuki; Shamoto, Shin-ichi; Kimura, Kaoru

    2010-11-22

    We report the effects of a neutron-capture reaction of isotope {sup 10}B on the structure and electrical transport of {sup 10}B-enriched single-crystalline boron nanobelts. Partial amorphization, particularly at the surface of the nanobelt, was observed after thermal neutron irradiation with a dose of 2x10{sup 19} cm{sup -2}. Carrier doping into the nanobelts by neutron transmutation is expected after postannealing. The change in conductance is discussed based on the distribution of localized states in the band gap of {alpha}-tetragonal boron.

  6. Small Reactor for Semiconductor Production by Neutron Transmutation Doping

    SciTech Connect

    Obara, Toru; Hong, Liem Peng

    2010-06-22

    New concept of small size nuclear reactor is proposed for Neutron Transmutation Doping (NTD). The reactor core consists of conventional PWR type fuel elements with light water moderator/coolant unlike conventional research reactors. Graphite reflector is employed for large neutron irradiation volume. Silicon ingots are put into the reflector region for irradiation. Neutronic analysis results show that this concept has possibility to product large amount of silicon ingots which have large diameter. An optimal reactor design and its performance are shown as a result of analysis in the paper.

  7. Impact of Including Higher Actinides in Fast Reactor Transmutation Analyses

    SciTech Connect

    B. Forget; M. Asgari; R. Ferrer; S. Bays

    2007-09-01

    Previous fast reactor transmutation studies generally disregarded higher mass minor actinides beyond Cm-246 due to various considerations including deficiencies in nuclear cross-section data. Although omission of these higher mass actinides does not significantly impact the neutronic calculations and fuel cycle performance parameters follow-on neutron dose calculations related to fuel recycling, transportation and handling are significantly impacted. This report shows that including the minor actinides in the equilibrium fast reactor calculations will increase the predicted neutron emission by about 30%. In addition a sensitivity study was initiated by comparing the impact of different cross-section evaluation file for representing these minor actinides.

  8. Nuclear data needs for accelerator-driven transmutation systems

    SciTech Connect

    Arthur, E.D.; Wilson, W.B.; Young, P.G.

    1994-07-01

    The possibilities of several new technologies based on use of intense, medium-energy proton accelerators are being investigated at Los Alamos National Laboratory. The potential new areas include destruction of long-lived components of nuclear waste, plutonium burning, energy production, and production of tritium. The design, assessment, and safety analysis of potential facilities involves the understanding of complex combinations of nuclear processes, which in turn places new requirements on nuclear data that transcend the traditional needs of the fission and fusion reactor communities. In this paper an assessment of the nuclear data needs for systems currently being considered in the Los Alamos Accelerator-Driven Transmutation Technologies program is given.

  9. Calculation of transmutation in copper and comparison with measured electrical properties

    SciTech Connect

    Greenwood, L.R.; Garner, F.A.; Edwards, D.J.

    1993-08-01

    Calculations of the transmutation of pure cooper have been performed for the Fast Flux Test Facility/Materials Open Test Assembly (FFTF/MOTA) and for the STARFIRE first-wall fusion reactor. The principal transmutation products in decreasing order of importance are nickel, zinc, and cobalt. Contrary to previously published calculations, nickel and zinc are produced at nearly equal rates in FFTF, but cobalt is insignificant. The fusion reactor case shows much higher transmutation rates and produces about twice as much nickel as zinc. Transmutation rates for FFTF were determined using adjusted neutron energy spectra based on dosimetry measurements at various positions in the MOTA. The predicted transmutation rates were compared directly with nickel concentrations measured by Energy Dispersive X-Ray Spectrometry (EDS) microchemistry and with measurements of the electrical conductivity of copper and two copper alloys irradiated in the MOTA. Measurements and calculations agree within {+-}15%.

  10. Feasibility study of nuclear transmutation by negative muon capture reaction using the PHITS code

    NASA Astrophysics Data System (ADS)

    Abe, Shin-ichiro; Sato, Tatsuhiko

    2016-06-01

    Feasibility of nuclear transmutation of fission products in high-level radioactive waste by negative muon capture reaction is investigated using the Particle and Heave Ion Transport code System (PHITS). It is found that about 80 % of stopped negative muons contribute to transmute target nuclide into stable or short-lived nuclide in the case of 135Cs, which is one of the most important nuclide in the transmutation. The simulation result also indicates that the position of transmutation is controllable by changing the energy of incident negative muon. Based on our simulation, it takes approximately 8.5 × 108years to transmute 500 g of 135Cs by negative muon beam with the highest intensity currently available.

  11. Practising alchemy: the transmutation of evidence into best health care.

    PubMed

    Goodyear-Smith, Felicity

    2011-04-01

    Alchemy was the synthesis or transmutation of all elements in perfect balance to obtain the philosopher's stone, the key to health. Just as alchemists sought this, so health practitioners always seek the best possible practice for optimal health outcomes for our patients. Best practice requires full knowledge--a little information can be dangerous. We need to serve our apprenticeship before we master our profession. Our profession is about improving health care. While the journey may start at medical school, the learning never ceases. It is not only about practising medicine, it is about the development of the practitioner. Professional practice requires systematic thinking combined with capacity to deal morally and creatively in areas of complexity and uncertainty appropriate to a specific context. It requires exemplary communication skills to interact with patients to facilitate collaborative decision making resulting in best practice. The synthesis of scientific and contextual evidence is a concept which applies to all disciplines where theoretical knowledge needs to be transferred to action to inform best practice. Decisions need to be made which take into account a complex array of factors, such as social and legal issues and resource constraints. Therefore, journey towards best practice involves transmutation of these three elements: scientific knowledge, the context in which it is applied and phronesis, the practical wisdom of the practitioner. All science has its limitations and we can never know all possible contextual information. Hence, like the philosopher's stone, best practice is a goal to which we aspire but never quite attain. PMID:21127021

  12. LDRD 140639 final report : investigation of transmutation claims.

    SciTech Connect

    Reich, Jeffrey E.; Van Devender, J. Pace; Mowry, Curtis Dale; Grant, Richard P.; Ohlhausen, James Anthony

    2009-11-01

    The Proton-21 Laboratory in the Ukraine has been publishing results on shock-induced transmutation of several elements, including Cobalt 60 into non-radioactive elements. This report documents exploratory characterization of a shock-compressed Aluminum-6061 sample, which is the only available surrogate for the high-purity copper samples in the Proton-21 experiments. The goal was to determine Sandia's ability to detect possible shock-wave-induced transmutation products and to unambiguously validate or invalidate the claims in collaboration with the Proton-21 Laboratory. We have developed a suitable characterization process and tested it on the surrogate sample. Using trace elemental analysis capabilities, we found elevated and localized concentrations of impurity elements like the Ukrainians report. All our results, however, are consistent with the ejection of impurities that were not in solution in our alloy or were deposited from the cathode during irradiation or possibly storage. Based on the detection capabilities demonstrated and additional techniques available, we are positioned to test samples from Proton-21 if funded to do so.

  13. Possible Nuclear Transmutation of Nitrogen in the Earth's Atmosphere

    NASA Astrophysics Data System (ADS)

    Fukuhara, Mikio

    2006-02-01

    An attempt to give a possible answer to a question why nitrogen exists so abundantly in Earth's atmosphere and how it was formed in Archean era (3.8-2.5 billion years ago) is presented. The nitrogen is postulated to be the result of an endothermic nuclear transmutation of carbon and oxygen nuclei confined in carbonate MgCO3 lattice of the mantle with an enhanced rate by attraction effect of catalysis of neutral pions, produced by electron emission: 12C + 16O - 2π0 → 2 14N. The excited electrons were generated by rapid fracture or sliding of carbonate crystals due to volcanic earthquake, and many of the neutrinos were derived from stars, mainly the young sun. The formation of nitrogen would continued for 1.3 billion years from 2.5 to 3.8 billion years in Archean era, until the active volcanism or storm of neutrinos ceased. The transformation is possible by the combined effects of the screening attraction of free electrons and thermal activation in deeper mantle. The possible nuclear transmutation rate of nitrogen atoms could be calculated as 2.3 × 106 atom/s.

  14. SCWR Once-Through Calculations for Transmutation and Cross Sections

    SciTech Connect

    ganda, francesco

    2012-07-01

    It is the purpose of this report to document the calculation of (1) the isotopic evolution and of (2) the 1-group cross sections as a function of burnup of the reference Super Critical Water Reactor (SCWR), in a format suitable for the Fuel Cycle Option Campaign Transmutation Data Library. The reference SCWR design was chosen to be that described in [McDonald, 2005]. Super Critical Water Reactors (SCWR) are intended to operate with super-critical water (i.e. H2O at a pressure above 22 MPa and a temperature above 373oC) as a cooling – and possibly also moderating – fluid. The main mission of the SCWR is to generate lower cost electricity, as compared to current standard Light Water Reactors (LWR). Because of the high operating pressure and temperature, SCWR feature a substantially higher thermal conversion efficiency than standard LWR – i.e. about 45% versus 33%, mostly due to an increase in the exit water temperature from ~300oC to ~500oC – potentially resulting in a lower cost of generated electricity. The coolant remains single phase throughout the reactor and the energy conversion system, thus eliminating the need for pressurizers, steam generators, steam separators and dryers, further potentially reducing the reactor construction capital cost. The SCWR concept presented here is based on existing LWR technology and on a large number of existing fossil-fired supercritical boilers. However, it was concluded in [McDonald, 2005], that: “Based on the results of this study, it appears that the reference SCWR design is not feasible.” This conclusion appears based on the strong sensitivity of the design to small deviations in nominal conditions leading to small effects having a potentially large impact on the peak cladding temperature of some fuel rods. “This was considered a major feasibility issue for the SCWR” [McDonald, 2005]. After a description of the reference SCWR design, the Keno V 3-D single assembly model used for this analysis, as well as the

  15. Prognosis and comparison of performances of composite CERCER and CERMET fuels dedicated to transmutation of TRU in an EFIT ADS

    NASA Astrophysics Data System (ADS)

    Sobolev, V.; Uyttenhove, W.; Thetford, R.; Maschek, W.

    2011-07-01

    The neutronic and thermomechanical performances of two composite fuel systems: CERCER with (Pu,Np,Am,Cm)O 2-x fuel particles in ceramic MgO matrix and CERMET with metallic Mo matrix, selected for transmutation of minor actinides in the European Facility for Industrial Transmutation (EFIT), were analysed aiming at their optimisation. The ALEPH burnup code system, based on MNCPX and ORIGEN codes and JEFF3.1 nuclear data library, and the modern version of the fuel rod performance code TRAFIC were used for this analysis. Because experimental data on the properties of the mixed minor-actinide oxides are scarce, and the in-reactor behaviour of the T91 steel chosen as cladding, as well as of the corrosion protective layer, is still not well-known, a set of "best estimates" provided the properties used in the code. The obtained results indicate that both fuel candidates, CERCER and CERMET, can satisfy the fuel design and safety criteria of EFIT. The residence time for both types of fuel elements can reach about 5 years with the reactivity swing within ±1000 pcm, and about 22% of the loaded MA is transmuted during this period. However, the fuel centreline temperature in the hottest CERCER fuel rod is close to the temperature above which MgO matrix becomes chemically instable. Moreover, a weak PCMI can appear in about 3 years of operation. The CERMET fuel can provide larger safety margins: the fuel temperature is more than 1000 K below the permitted level of 2380 K and the pellet-cladding gap remains open until the end of operation.

  16. Utilization of accelerators for transmutation and energy production

    SciTech Connect

    Sheffield, Richard L

    2010-09-24

    Given the increased concern over reliable, emission-free power, nuclear power has experienced a resurgence of interest. A sub-critical accelerator driven system (ADS) can drive systems that have either safety constraints (waste transmutation) or reduced fissile content (thorium reactor). The goals of ADS are some or all of the following: (1) to significantly reduce the generation or impacts due to the minor actinides on the packing density and long-term radiotoxicity in the repository design, (2) preserve/use the energy-rich component of used nuclear fuel, and (3) reduce proliferation risk. ADS systems have been actively studied in Europe and Asia over the past two decades and renewed interest is occurring in the U.S. This talk will cover some of the history, possible applicable fuel cycle scenarios, and general issues to be considered in implementing ADS systems.

  17. Accelerator-Driven Systems for Nuclear Waste Transmutation

    NASA Astrophysics Data System (ADS)

    Bowman, Charles D.

    The renewed interest since 1990 in accelerator-driven subcritical systems for transmutation of commercial nuclear waste has evolved to focus on the issue of whether fast- or thermal-spectrum systems offer greater promise. This review addresses the issue by comparing the performance of the more completely developed thermal- and fast-spectrum designs. Substantial design information is included to allow an assessment of the viability of the systems compared. The performance criteria considered most important are (a) the rapidity of reduction of the current inventory of plutonium and minor actinide from commercial spent fuel, (b) the cost, and (c) the complexity. The liquid-fueled thermal spectrum appears to offer major advantages over the solid-fueled fast-spectrum system, making waste reduction possible with about half the capital requirement on a substantially shorter time scale and with smaller separations requirements.

  18. Description of Transmutation Library for Fuel Cycle System Analyses

    SciTech Connect

    Steven J. Piet; Samuel E. Bays; Edward A. Hoffman

    2010-08-01

    This report documents the Transmutation Library that is used in Fuel Cycle System Analyses. This version replaces the 2008 version.[Piet2008] The Transmutation Library has the following objectives: • Assemble past and future transmutation cases for system analyses. • For each case, assemble descriptive information such as where the case was documented, the purpose of the calculation, the codes used, source of feed material, transmutation parameters, and the name of files that contain raw or source data. • Group chemical elements so that masses in separation and waste processes as calculated in dynamic simulations or spreadsheets reflect current thinking of those processes. For example, the CsSr waste form option actually includes all Group 1A and 2A elements. • Provide mass fractions at input (charge) and output (discharge) for each case. • Eliminate the need for either “fission product other” or “actinide other” while conserving mass. Assessments of waste and separation cannot use “fission product other” or “actinide other” as their chemical behavior is undefined. • Catalog other isotope-specific information in one place, e.g., heat and dose conversion factors for individual isotopes. • Describe the correlations for how input and output compositions change as a function of UOX burnup (for LWR UOX fuel) or fast reactor (FR) transuranic (TRU) conversion ratio (CR) for either FR-metal or FR-oxide. This document therefore includes the following sections: • Explanation of the data set information, i.e., the data that describes each case. In no case are all of the data presented in the Library included in previous documents. In assembling the Library, we return to raw data files to extract the case and isotopic data, into the specified format. • Explanation of which isotopes and elements are tracked. For example, the transition metals are tracked via the following: two Zr isotopes, Zr-other, Tc99, Tc-other, two Mo-Ru-Rh-Pd isotopes, Mo

  19. Americium Transmutation Feasibility When Used as Burnable Absorbers - 12392

    SciTech Connect

    Barbaras, Sean A.; Knight, Travis W.

    2012-07-01

    The use of plutonium in Mixed Oxide (MOX) fuel in traditional Pressurized Water Reactor (PWR) assemblies leads to greater americium production which is not addressed in MOX recycling. The transuranic nuclides (TRU) contribute the most to the radiotoxicity of nuclear waste and a reduction of the TRU stockpile would greatly reduce the overall radiotoxicity of what must be managed. Am-241 is a TRU of particular concern because it is the dominant contributor of total radiotoxicity for the first 1000 years in a repository. This research explored the feasibility of transmuting Am-241 by using varying amounts in MOX rods being used in place of burnable absorbers and evaluated with respect to the impact on incineration and transmutation of transuranics in MOX fuel as well as the impact on safety. This research concludes that the addition of americium to a non-uniform fuel assembly is a viable method of transmuting Am-241, holding down excess reactivity in the core while serving as a burnable poison, as well as reducing the radiotoxicity of high level waste that must be managed. The use of Am/MOX hybrid fuel assemblies to transmute americium was researched using multiple computer codes. Am-241 was shown in this study to be able to hold down excess reactivity at the beginning of cycle and shape the power distribution in the core with assemblies of varying americium content loaded in a pattern similar to the traditional use of assemblies with varying amounts of burnable absorbers. The feasibility, safety, and utility of using americium to create an Am/MOX hybrid non-uniform core were also evaluated. The core remained critical to a burnup of 22,000 MWD/MTM. The power coefficient of reactivity as well as the temperature and power defects were sufficiently negative to provide a prompt feedback mechanism in case of a transient and prevent a power excursion, thus ensuring inherent safety and protection of the core. As shown here as well as many other studies, this non

  20. The physics design of accelerator-driven transmutation systems

    SciTech Connect

    Venneri, F.

    1995-02-01

    Nuclear systems under study in the Los Alamos Accelerator-Driven Transmutation Technology program (ADTT) will allow the destruction of nuclear spent fuel and weapons-return plutonium, as well as the production of nuclear energy from the thorium cycle, without a long-lived radioactive waste stream. The subcritical systems proposed represent a radical departure from traditional nuclear concepts (reactors), yet the actual implementation of ADTT systems is based on modest extrapolations of existing technology. These systems strive to keep the best that the nuclear technology has developed over the years, within a sensible conservative design envelope and eventually manage to offer a safer, less expensive and more environmentally sound approach to nuclear power.

  1. An omnidirectional retroreflector based on the transmutation of dielectric singularities.

    PubMed

    Ma, Yun Gui; Ong, C K; Tyc, Tomás; Leonhardt, Ulf

    2009-08-01

    Transformation optics is a concept used in some metamaterials to guide light on a predetermined path. In this approach, the materials implement coordinate transformations on electromagnetic waves to create the illusion that the waves are propagating through a virtual space. Transforming space by appropriately designed materials makes devices possible that have been deemed impossible. In particular, transformation optics has led to the demonstration of invisibility cloaking for microwaves, surface plasmons and infrared light. Here, on the basis of transformation optics, we implement a microwave device that would normally require a dielectric singularity, an infinity in the refractive index. To fabricate such a device, we transmute a dielectric singularity in virtual space into a mere topological defect in a real metamaterial. In particular, we demonstrate an omnidirectional retroreflector, a device for faithfully reflecting images and for creating high visibility from all directions. Our method is robust, potentially broadband and could also be applied to visible light using similar techniques. PMID:19561598

  2. FUEL CYCLE ISOTOPE EVOLUTION BY TRANSMUTATION DYNAMICS OVER MULTIPLE RECYCLES

    SciTech Connect

    Samuel Bays; Steven Piet; Amaury Dumontier

    2010-06-01

    Because all actinides have the ability to fission appreciably in a fast neutron spectrum, these types of reactor systems are usually not associated with the buildup of higher mass actinides: curium, berkelium and californium. These higher actinides have high specific decay heat power, gamma and neutron source strengths, and are usually considered as a complication to the fuel manufacturing and transportation of fresh recycled transuranic fuel. This buildup issue has been studied widely for thermal reactor fuels. However, recent studies have shown that the transmutation physics associated with "gateway isotopes" dictates Cm-Bk-Cf buildup, even in fast burner reactors. Assuming a symbiotic fuel relationship with light water reactors (LWR), Pu-242 and Am-243 are formed in the LWRs and then are externally fed to the fast reactor as part of its overall transuranic fuel supply. These isotopes are created much more readily in a thermal than in fast spectrum systems due to the differences in the fast fission (i.e., above the fission threshold for non-fissile actinides) contribution. In a strictly breeding fast reactor this dependency on LWR transuranics would not exist, and thus avoids the introduction of LWR derived gateway isotopes into the fast reactor system. However in a transuranic burning fast reactor, the external supply of these gateway isotopes behaves as an external driving force towards the creation and build-up of Cm-Bk-Cf in the fuel cycle. It was found that though the Cm-Bk-Cf concentration in the equilibrium fuel cycle is dictated by the fast neutron spectrum, the time required to reach that equilibrium concentration is dictated by recycle, transmutation and decay storage dynamics.

  3. Conceptual study of fusion-driven transmutation reactor with ITER physics and engineering constraints

    NASA Astrophysics Data System (ADS)

    Hong, Bong

    2011-10-01

    A conceptual study of fusion-driven transmutation reactor was performed based on ITER physics and engineering constraints. A compact reactor concept is desirable from an economic viewpoint. For the optimal design of a reactor, a radial build of reactor components has to be determined by considering the plasma physics and engineering constraints which inter-relate various reactor components. In a transmutation reactor, design of blanket and shield play a key role in determining the size of a reactor; the blanket should produce enough tritium for tritium self-sufficiency, the transmutation rate of waste has to be maximized, and the shield should provide sufficient protection for the superconducting toroidal field (TF) coil. To determine the radial build of the blanket and the shield, not only a radiation transport analysis but also a burnup calculation were coupled with the system analysis and it allowed the self-consistent determination of the design parameters of a transmutation reactor.

  4. Analysis of advanced european nuclear fuel cycle scenarios including transmutation and economical estimates

    SciTech Connect

    Merino Rodriguez, I.; Alvarez-Velarde, F.; Martin-Fuertes, F.

    2013-07-01

    In this work the transition from the existing Light Water Reactors (LWR) to the advanced reactors is analyzed, including Generation III+ reactors in a European framework. Four European fuel cycle scenarios involving transmutation options have been addressed. The first scenario (i.e., reference) is the current fleet using LWR technology and open fuel cycle. The second scenario assumes a full replacement of the initial fleet with Fast Reactors (FR) burning U-Pu MOX fuel. The third scenario is a modification of the second one introducing Minor Actinide (MA) transmutation in a fraction of the FR fleet. Finally, in the fourth scenario, the LWR fleet is replaced using FR with MOX fuel as well as Accelerator Driven Systems (ADS) for MA transmutation. All scenarios consider an intermediate period of GEN-III+ LWR deployment and they extend for a period of 200 years looking for equilibrium mass flows. The simulations were made using the TR-EVOL code, a tool for fuel cycle studies developed by CIEMAT. The results reveal that all scenarios are feasible according to nuclear resources demand (U and Pu). Concerning to no transmutation cases, the second scenario reduces considerably the Pu inventory in repositories compared to the reference scenario, although the MA inventory increases. The transmutation scenarios show that elimination of the LWR MA legacy requires on one hand a maximum of 33% fraction (i.e., a peak value of 26 FR units) of the FR fleet dedicated to transmutation (MA in MOX fuel, homogeneous transmutation). On the other hand a maximum number of ADS plants accounting for 5% of electricity generation are predicted in the fourth scenario (i.e., 35 ADS units). Regarding the economic analysis, the estimations show an increase of LCOE (Levelized cost of electricity) - averaged over the whole period - with respect to the reference scenario of 21% and 29% for FR and FR with transmutation scenarios respectively, and 34% for the fourth scenario. (authors)

  5. Technical and economic assessment of different options for minor actinide transmutation: the French case

    SciTech Connect

    Chabert, C.; Coquelet-Pascal, C.; Saturnin, A.; Mathonniere, G.; Boullis, B.; Warin, D.; Van Den Durpel, L.; Caron-Charles, M.; Garzenne, C.

    2013-07-01

    Studies have been performed to assess the industrial perspectives of partitioning and transmutation of long-lived elements. These studies were carried out in tight connection with GEN-IV systems development. The results include the technical and economic evaluation of fuel cycle scenarios along with different options for optimizing the processes between the minor actinide transmutation in fast neutron reactors, their interim storage and geological disposal of ultimate waste. The results are analysed through several criteria (impacts on waste, on waste repository, on fuel cycle plants, on radiological exposure of workers, on costs and on industrial risks). These scenario evaluations take place in the French context which considers the deployment of the first Sodium-cooled Fast Reactor (SFR) in 2040. 3 management options of minor actinides have been studied: no transmutation, transmutation in SFR and transmutation in an accelerator-driven system (ADS). Concerning economics the study shows that the cost overrun related to the transmutation process could vary between 5 to 9% in SFR and 26 % in the case of ADS.

  6. FIRST-PRINCIPLES CALCULATIONS OF INTRINSIC DEFECTS AND Mg TRANSMUTANTS IN 3C-SiC

    SciTech Connect

    Hu, Shenyang Y.; Setyawan, Wahyu; Van Ginhoven, Renee M.; Jiang, Weilin; Henager, Charles H.; Kurtz, Richard J.

    2013-09-25

    Silicon carbide (SiC) possesses many desirable attributes for applications in high-temperature and neutron radiation environments. These attributes include excellent dimensional and thermodynamic stability, low activation, high strength, and high thermal conductivity. Therefore, SiC based materials draw broad attention as structural materials for the first wall (FW) and blanket in fusion power plants. Under the severe high-energy neutron environment of D-T fusion systems, SiC suffers significant transmutation resulting in both gaseous and metallic transmutants. Recent calculations by Sawan, et al. [2] predict that at a fast neutron dose of ~100 dpa, there will be about 0.5 at% Mg generated in SiC through nuclear transmutation. Other transmutation products, including 0.15 at% Al, 0.2 at% Be and 2.2 at% He, also emerge. Formation and migration energies of point defects in 3C-SiC have been widely investigated using density functional theory (DFT). However, the properties of defects associated with transmutants are currently not well understood. Fundamental understanding of where the transmutation products go and how they affect microstructure evolution of SiC composites will help to predict property evolution and performance of SiC-based materials in fusion reactors.

  7. HYPERFUSE: a hypervelocity inertial confinement system for fusion energy production and fission waste transmutation

    SciTech Connect

    Makowitz, H; Powell, J R; Wiswall, R

    1980-01-01

    Parametric system studies of an inertial confinement fusion (ICF) reactor system to transmute fission products from an LWR economy have been carried out. The ICF reactors would produce net power in addition to transmuting fission products. The particular ICF concept examined is an impact fusion approach termed HYPERFUSE, in which hypervelocity pellets, traveling on the order of 100 to 300 km/sec, collide with each other or a target block in a reactor chamber and initiate a thermonuclear reaction. The DT fusion fuel is contained in a shell of the material to be transmuted, e.g., /sup 137/Cs, /sup 90/Sr, /sup 129/I, /sup 99/Tc, etc. The 14-MeV fusion neutrons released during the pellet burn cause transmutation reactions (e.g., (n,2n), (n,..cap alpha..), (n,..gamma..), etc.) that convert the long-lived fission products (FP's) either to stable products or to species that decay with a short half-life to a stable product. The transmutation parametric studies conclude that the design of the hypervelocity projectiles should emphasize the achievement of high densities in the transmutation regions (greater than the DT fusion fuel density), as well as the DT ignition and burn criterion (rho R=1.0 to 3.0) requirements.

  8. Assessment of SFR fuel pin performance codes under advanced fuel for minor actinide transmutation

    SciTech Connect

    Bouineau, V.; Lainet, M.; Chauvin, N.; Pelletier, M.

    2013-07-01

    Americium is a strong contributor to the long term radiotoxicity of high activity nuclear waste. Transmutation by irradiation in nuclear reactors of long-lived nuclides like {sup 241}Am is, therefore, an option for the reduction of radiotoxicity and residual power packages as well as the repository area. In the SUPERFACT Experiment four different oxide fuels containing high and low concentrations of {sup 237}Np and {sup 241}Am, representing the homogeneous and heterogeneous in-pile recycling concepts, were irradiated in the PHENIX reactor. The behavior of advanced fuel materials with minor actinide needs to be fully characterized, understood and modeled in order to optimize the design of this kind of fuel elements and to evaluate its performances. This paper assesses the current predictability of fuel performance codes TRANSURANUS and GERMINAL V2 on the basis of post irradiation examinations of the SUPERFACT experiment for pins with low minor actinide content. Their predictions have been compared to measured data in terms of geometrical changes of fuel and cladding, fission gases behavior and actinide and fission product distributions. The results are in good agreement with the experimental results, although improvements are also pointed out for further studies, especially if larger content of minor actinide will be taken into account in the codes. (authors)

  9. Transmutation of Isotopes --- Ecological and Energy Production Aspects

    NASA Astrophysics Data System (ADS)

    Gudowski, Waclaw

    2000-01-01

    This paper describes principles of Accelerator-Driven Transmutation of Nuclear Wastes (ATW) and gives some flavour of the most important topics which are today under investigations in many countries. An assessment of the potential impact of ATW on a future of nuclear energy is also given. Nuclear reactors based on self-sustained fission reactions --- after spectacular development in fifties and sixties, that resulted in deployment of over 400 power reactors --- are wrestling today more with public acceptance than with irresolvable technological problems. In a whole spectrum of reasons which resulted in today's opposition against nuclear power few of them are very relevant for the nuclear physics community and they arose from the fact that development of nuclear power had been handed over to the nuclear engineers and technicians with some generically unresolved problems, which should have been solved properly by nuclear scientists. In a certain degree of simplification one can say, that most of the problems originate from very specific features of a fission phenomenon: self-sustained chain reaction in fissile materials and very strong radioactivity of fission products and very long half-life of some of the fission and activation products. And just this enormous concentration of radioactive fission products in the reactor core is the main problem of managing nuclear reactors: it requires unconditional guarantee for the reactor core integrity in order to avoid radioactive contamination of the environment; it creates problems to handle decay heat in the reactor core and finally it makes handling and/or disposal of spent fuel almost a philosophical issue, due to unimaginable long time scales of radioactive decay of some isotopes. A lot can be done to improve the design of conventional nuclear reactors (like Light Water Reactors); new, better reactors can be designed but it seems today very improbable to expect any radical change in the public perception of conventional

  10. Gas core reactors for actinide transmutation. [uranium hexafluoride

    NASA Technical Reports Server (NTRS)

    Clement, J. D.; Rust, J. H.; Wan, P. T.; Chow, S.

    1979-01-01

    The preliminary design of a uranium hexafluoride actinide transmutation reactor to convert long-lived actinide wastes to shorter-lived fission product wastes was analyzed. It is shown that externally moderated gas core reactors are ideal radiators. They provide an abundant supply of thermal neutrons and are insensitive to composition changes in the blanket. For the present reactor, an initial load of 6 metric tons of actinides is loaded. This is equivalent to the quantity produced by 300 LWR-years of operation. At the beginning, the core produces 2000 MWt while the blanket generates only 239 MWt. After four years of irradiation, the actinide mass is reduced to 3.9 metric tonnes. During this time, the blanket is becoming more fissile and its power rapidly approaches 1600 MWt. At the end of four years, continuous refueling of actinides is carried out and the actinide mass is held constant. Equilibrium is essentially achieved at the end of eight years. At equilibrium, the core is producing 1400 MWt and the blanket 1600 MWt. At this power level, the actinide destruction rate is equal to the production rate from 32 LWRs.

  11. Electrical properties of neutron-transmutation-doped germanium

    SciTech Connect

    Rodder, M.

    1982-08-01

    Electrical properties of neutron-transmutation-doped germanium (NTD Ge) and nearly uncompensated gallium-doped germanium have been measured as functions of net-impurity concentration (2 x 10/sup 15/cm/sup -3/ less than or equal to N/sub A/ - N/sub D/ less than or equal to 5 x 10/sup 16/cm/sup -3/) and temperature (0.3 K less than or equal to T less than or equal to 300 K). The method of impurity conduction as a function of carrier concentration and compensation was investigated in the low temperature hopping regime. For nearest neighbor hopping, the resistivity is expected to vary as rho = rho/sub 0/exp(..delta../T) while Mott's theory of variable range hopping predicts that rho = rho/sub 0/exp(..delta../T)/sup 1/4/ in the low temperature limit. In contrast, our results show that the resistivity can best be approximated by rho = rho/sub 0/exp(..delta../T)/sup 1/2/ in the hopping regime down to 0.3 K.

  12. Compton Radiation for Nuclear Waste Management and Transmutation

    NASA Astrophysics Data System (ADS)

    Bulyak, E.; Urakawa, J.

    2015-10-01

    Compton inverse radiation is emitted in the process of backscattering of the laser pulses off the relativistic electrons. This radiation possesses high spectral density and high energy of photons--in hard x-ray up to gammaray energy range--with moderate electron energies (hundreds of MeV up to 1 GeV) due to short wavelength of the laser radiation. The Compton radiation is well collimated: emitting within a narrow cone along the electron beam. A distinct property of the Compton inverse radiation is a steep high-energy cutoff of the spectrum and the maximal intensity just below the cutoff. The Compton sources can attain: spectral density up to 1014 gammas/(s 0.1%bandwidth) in MeV range of energies, and spectral brightness up to 1020 gammas/(smm2mr2 0.1% bw). Applicability of Compton sources for nuclear waste management and detection of radioisotopes and fissionable nuclides are discussed in the report. Also application limits of Compton gamma sources for transmutation of radioactive isotopes are estimated. A recently proposed subtracting method, in which two sets of data obtained by irradiating the object by the Compton beams with slightly different maximal energies are compared, will enhance resolution of detection radioactive elements at the 'atomic' (hundreds of keV) and the 'nuclear' (a few MeV) photon energies.

  13. HYPERFUSE: a hypervelocity inertial confinement system for fusion energy production and fission waste transmutation

    SciTech Connect

    Makowitz, H.; Powell, J.R.; Wiswall, R.

    1980-01-01

    Parametric system studies of an inertial confinement fusion (ICF) reactor system to transmute fission products from a LWR economy have been carried out. The ICF reactors would produce net power in addition to transmuting fission products. The particular ICF concept examined is an impact fusion approach termed HYPERFUSE, in which hypervelocity pellets, traveling on the order of 100 to 300 km/sec, collide with each other or a target block in a reactor chamber and initiate a thermonuclear reaction. The DT fusion fuel is contained in a shell of the material to be transmuted, e.g., /sup 137/Cs, /sup 90/Sr, /sup 129/I, /sup 99/Tc, etc. The 14-MeV fusion neutrons released during the pellet burn cause transmutation reactions (e.g., (n,2n), (n,..cap alpha..), (n,..gamma..), etc.) that convert the long-lived fission products (FP's) either to stable products or to species that decay with a short half-life to a stable product. The transmutation parametric studies conclude that the design of the hypervelocity projectiles should emphasize the achievement of high densities in the transmutation regions (greater than the DT fusion fuel density), as well as the DT ignition and burn criterion (rho R = 1.0 to 3.0) requirements. These studies also indicate that masses on the order of 1.0 g at densities of rho greater than or equal to 500.0 g/cm/sup 3/ are required for a practical fusion-based fission product transmutation system.

  14. Phase Formation and Transformations in Transmutation Fuel Materials for the LIFE Engine Part I - Path Forward

    SciTech Connect

    Turchi, P E; Kaufman, L; Fluss, M J

    2008-11-10

    The current specifications of the LLNL fusion-fission hybrid proposal, namely LIFE, impose severe constraints on materials, and in particular on the nuclear fissile or fertile nuclear fuel and its immediate environment. This constitutes the focus of the present report with special emphasis on phase formation and phase transformations of the transmutation fuel and their consequences on particle and pebble thermal, chemical and mechanical integrities. We first review the work that has been done in recent years to improve materials properties under the Gen-IV project, and with in particular applications to HTGR and MSR, and also under GNEP and AFCI in the USA. Our goal is to assess the nuclear fuel options that currently exist together with their issues. Among the options, it is worth mentioning TRISO, IMF, and molten salts. The later option will not be discussed in details since an entire report is dedicated to it. Then, in a second part, with the specific LIFE specifications in mind, the various fuel options with their most critical issues are revisited with a path forward for each of them in terms of research, both experimental and theoretical. Since LIFE is applicable to very high burn-up of various fuels, distinctions will be made depending on the mission, i.e., energy production or incineration. Finally a few conclusions are drawn in terms of the specific needs for integrated materials modeling and the in depth knowledge on time-evolution thermochemistry that controls and drastically affects the performance of the nuclear materials and their immediate environment. Although LIFE demands materials that very likely have not yet been fully optimized, the challenge are not insurmountable and a well concerted experimental-modeling effort should lead to dramatic advances that should well serve other fission programs such as Gen-IV, GNEP, AFCI as well as the international fusion program, ITER.

  15. Optimisation of composite metallic fuel for minor actinide transmutation in an accelerator-driven system

    NASA Astrophysics Data System (ADS)

    Uyttenhove, W.; Sobolev, V.; Maschek, W.

    2011-09-01

    A potential option for neutralization of minor actinides (MA) accumulated in spent nuclear fuel of light water reactors (LWRs) is their transmutation in dedicated accelerator-driven systems (ADS). A promising fuel candidate dedicated to MA transmutation is a CERMET composite with Mo metal matrix and (Pu, Np, Am, Cm)O 2-x fuel particles. Results of optimisation studies of the CERMET fuel targeting to increasing the MA transmutation efficiency of the EFIT (European Facility for Industrial Transmutation) core are presented. In the adopted strategy of MA burning the plutonium (Pu) balance of the core is minimized, allowing a reduction in the reactivity swing and the peak power form-factor deviation and an extension of the cycle duration. The MA/Pu ratio is used as a variable for the fuel optimisation studies. The efficiency of MA transmutation is close to the foreseen theoretical value of 42 kg TW -1 h -1 when level of Pu in the actinide mixture is about 40 wt.%. The obtained results are compared with the reference case of the EFIT core loaded with the composite CERCER fuel, where fuel particles are incorporated in a ceramic magnesia matrix. The results of this study offer additional information for the EFIT fuel selection.

  16. Transmutation abilities of the SFR low void effect core concept 'CFV' 3600 MWth

    SciTech Connect

    Buiron, L.; Fontaine, B.; Andriolo, L.

    2012-07-01

    This paper presents an evaluation of the potential of minor actinide transmutation in a 3600 MWth SFR core designed with the low void effect core concept (namely 'CFV concept'). This concept is based upon an axially heterogeneous design with an internal fertile zone, and two radial fuel zones with different heights. Two modes of minor actinide transmutation are considered. The homogeneous mode where the minor actinides (MA) are diluted in the fuel is studied considering different options: - MA diluted in the whole core, - MA diluted in the internal and external fuel zone, - MA diluted in the internal fertile zone, for which different isotopic vectors and contents in fuel are analyzed. The heterogeneous mode is also studied with MA placed in external blanket bearings, with contents of 20%. The results are compared to those obtained with a traditional homogenous core concept (SFRV2B type) in terms of transmutation performances. Impacts of the transmutation assumptions on transmutation performances, on fuel cycle and safety parameters (void effect, Doppler) are also presented. (authors)

  17. Incentives and recent proposals for partitioning and transmutation in the United States

    SciTech Connect

    Donovan, T.J.

    1995-05-01

    Partitioning and transmutation (P-T) is perhaps the most elegant means of high level waste disposal. Currently, the cost of fuel obtained from reprocessing spent fuel exceeds the cost of fuel obtained by mining. This has resulted in the once through fuel cycle dominating the US nuclear industry. Despite this fact P-T continues to be examined and debated by the US as well as abroad. The US first seriously considered P-T between approximately 1976 and 1982 but rejected the concept in favor of reprocessing. More recently, since about 1989, as a result of the once through fuel cycle and the growing problems of waste disposal, studies concerning P-T have resumed. This essay will seek to outline the incentives and goals of partitioning and transmutation as it would apply to the disposal of spent fuel in the US. Recent proposals by various US national laboratories for implementing partitioning and transmutation as a high level waste management and disposal device will also be discussed. The review will seek to examine the technical concepts utilized in each of the proposals and their feasibility. The major focus of this essay will be the transmutation methods themselves, while the partitioning methods will be discussed only briefly. This is because of the fact that partitioning methods fall under reprocessing as an already fairly well established and accepted technology while feasible methods for transmutation are still being advanced.

  18. Strain and texture measurements on geological samples using neutron diffraction at IBR-2, Joint Institute for Nuclear Research, Dubna (Russia)

    NASA Astrophysics Data System (ADS)

    Frischbutter, A.; Janssen, Ch.; Scheffzük, Ch.; Walther, K.; Ullemeyer, K.; Behrmann, J. H.; Nikitin, A. N.; Ivankina, T. I.; Kern, H.; Leiss, B.

    2006-12-01

    Information on texture and residual stress in geological samples is very important for the calculation of physical properties connected with the evaluation of the geomechanical behavior of parts of the earths’s crust in connection with processes from human activities (mining, tunnelling) and natural processes of deformation (seismicity, earthquakes). Texture and stress are not independent of each other and in the general case should be analyzed together. Complications arise because geological samples are generally composed of several phases (minerals) whose elastic constants may be significantly different. Nevertheless, modern neutron diffractometers such as SKAT and EPSILON-MDS at the fast pulsed reactor IBR-2 at the FLNP of the JINR make it possible to obtain the needed diffraction patterns. This was shown especially for texture measurements on samples with quartz as the main component as well as for mica, feldspar, amphibole, and several other minerals. In order to extend strain measurements beyond samples composed of quartz, dolomite, and/or anhydrite to such frequently occurring minerals as feldspars and mica it would be necessary on the one hand to use Rietveld refinement with corrections due to texture and anisotropic peak broadening. With an increase in the number of mineral phases suitable for these diffractometers, it is in general necessary to improve the experimental conditions for SKAT and EPSILON-MDS, especially to significantly raise the flux of incident neutrons on the sample.

  19. Comparison of accelerator-based with reactor-based waste transmutation schemes

    SciTech Connect

    Sailor, W.C.; Beard, C.A.; Venneri, F.; Davidson, J.W.

    1993-12-01

    Accelerator-based transmutation of waste (ATW) systems for the destruction of commercial LWR spent fuel are compared with systems based on thermal reactors accomplish the same objectives. When the same technology is assumed for the actinide-burning aspect of the two systems, it is seen that the size of the accelerator is determined only by the choice of how many of the long-lived fission products to burn. if none are transmuted, then the accelerator is not necessary. This result is independent of the choice of fluid carrier, and whether the actinides are destroyed in an ATW system or in a separate reactor.

  20. Calculation and measurement of helium generation and solid transmutations in Cu-Zn-Ni alloys

    SciTech Connect

    Greenwood, L.R.; Oliver, B.M.; Garner, F.A.; Muroga, T.

    1998-03-01

    A method was recently proposed by Garner and Greenwood that would allow the separation of the effects of solid and gaseous transmutation for Cu-Zn-Ni alloys. Pure copper produces zinc and nickel during neutron irradiation. {sup 63}Cu transmutes to {sup 64}Ni and {sup 64}Zn, in about a 2-to-1 ratio, and {sup 65}Cu transmutes to {sup 66}Zn. The {sup 64}Zn further transmutes to {sup 65}Zn which has been shown to have a high thermal neutron (n,{alpha}) cross-section. Since a three-step reaction sequence is required for natural copper, the amount of helium produced is much smaller than would be produced for the two-step, well-known {sup 58}Ni (n,{gamma}) {sup 59}Ni (n,{alpha}) reaction sequence. The addition of natural Zn and Ni to copper leads to greatly increased helium production in neutron spectra with a significant thermal component. Using a suitable Cu-Zn-Ni alloy matrix and comparative irradiation of thermal neutron-shielded and unshielded specimens, it should be possible to distinguish the separate influences of the solid and gaseous transmutants. Whereas helium generation rates have been previously measured for natural nickel and copper, they have not been measured for natural Zn or Cu-Ni-Zn alloys. The (N,{alpha}) cross section for {sup 65}Zn was inferred from helium measurements made with natural copper. By comparing helium production in Cu and Cu-Zn alloys, this cross section can be determined more accurately. In the current study, both the solid and helium transmutants were measured for Cu, Cu-5Ni, Cu-3.5Zn and Cu-5Ni-2Zn, irradiated in each of two positions in the HFIR JP-23 test. Highly accurate helium measurements were performed on these materials by isotope dilution mass spectrometry using a facility that was recently moved from Rockwell International to PNNL. It is shown that both the helium and solid transmutants for Cu-zn-Ni alloys can be calculated with reasonable certainty, allowing the development of a transmutation experiment as proposed by

  1. Boson-fermion and fermion-boson transmutations induced by supergravity backgrounds in superstring theory

    NASA Astrophysics Data System (ADS)

    de Vega, H. J.; Medrano, M. Ramon; Sanchez, N.

    1992-07-01

    We investigate the physical implications and particle content of superstring scattering in the supergravity shock-wave background recently found by us. The amplitudes for the different particle transmutation processes taking place in this geometry are explicitly computed for Gree-Schwarz superstring, including the new phenomena of fermion to boson and boson to fermion transmutations. Transition amplitudes among the ground states, first and second excited states are obtained. Particularly interesting are the amplitudes within the massless particle sector, which lead to physical massive particles upon supersymmetry breaking at low energies.

  2. Transmutation-induced embrittlement of V-Ti-Ni and V-Ni alloys in HFIR

    SciTech Connect

    Ohnuki, S.; Takahashi, H.; Garner, F.A.; Pawel, J.E.

    1996-04-01

    Vanadium, V-1Ni, V-10Ti and V-10Ti-1Ni (at %) were irradiated in HFIR to doses ranging from 18 to 30 dpa and temperatures between 300 and 600C. Since the irradiation was conducted in a highly thermalized neutron spectrum without shielding against thermal neutrons, significant levels of chromium (15-22%) were formed by transmutation. The addition of such large chromium levels strongly elevated the ductile to brittle transition temperature. At higher irradiation temperatures radiation-induced segregation of transmutant Cr and solute Ti at specimen surfaces leads to strong increases in the density of the alloy.

  3. Enhancements to transmutation system performance through use of an accelerator/fluid fuel combination

    SciTech Connect

    Arthur, E.D.; Buksa, J.; Davidson, J.W.; Poston, D.

    1995-07-01

    The destruction of plutonium and other long-lived radionuclides in high-level nuclear waste is receiving considerable international technical interest and effort. At Los Alamos, accelerator-based concepts are under investigation which achieve high burnups of plutonium and other actinides and which simultaneously transmute key long-lived fission products. This paper describes quantitative enhancements brought through use of an accelerator-driven/fluid fuel subcritical blanket. Results are described covering robust response to reactivity insertions, increased neutron economy for transmutation of long-lived fission products using thermal neutrons, and reduced frequencies required for fuel cleanup.

  4. Practical Combinations of Light-Water Reactors and Fast-Reactors for Future Actinide Transmutation

    SciTech Connect

    Collins, Emory D; Renier, John-Paul

    2007-01-01

    Multicycle partitioning-transmutation (P-T) studies continue to show that use of existing light-water reactors (LWRs) and new advanced light-water reactors (ALWRs) can effectively transmute transuranic (TRU) actinides, enabling initiation of full actinide recycle much earlier than waiting for the development and deployment of sufficient fast reactor (FR) capacity. The combination of initial P-T cycles using LWRs/ALWRs in parallel with economic improvements to FR usage for electricity production, and a follow-on transition period in which FRs are deployed, is a practical approach to near-term closure of the nuclear fuel cycle with full actinide recycle.

  5. U.S. Plans for the Next Fast Reactor Transmutation Fuels Irradiation Test

    SciTech Connect

    B. A. Hilton

    2007-09-01

    The U.S. Advanced Fuel Cycle Initiative (AFCI) seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products, thereby dramatically decreasing the volume of material requiring disposal and the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository. One important component of the technology development is actinide-bearing transmutation fuel forms containing plutonium, neptunium, americium (and possibly curium) isotopes. Metallic alloy and oxide fuel forms are being developed as the near term options for fast reactor implementation.

  6. Chemistry technology base and fuel cycle of the Los Alamos accelerator-driven transmutation system

    SciTech Connect

    Williamson, M.A.

    1997-12-01

    This paper provides a brief overview of the Los Alamos accelerator-driven transmutation system, a description of the pyrochemistry technology base and the fuel cycle for the system. The pyrochemistry technology base consists of four processes: direct oxide reduction, reductive extraction, electrorefining, and electrowinning. Each process and its utility is described. The fuel cycle is described for a liquid metal-based system with the focus being the conversion of commercial spent nuclear fuel to fuel for the transmutation system. Fission product separation and actinide recycle processes are also described.

  7. Irradiaton of Metallic and Oxide Fuels for Actinide Transmutation in the ATR

    SciTech Connect

    Heather J. MacLean; Steven L. Hayes

    2007-09-01

    Metallic fuels containing minor actinides and rare earth additions have been fabricated and are prepared for irradiation in the ATR, scheduled to begin during the summer of 2007. Oxide fuels containing minor actinides are being fabricated and will be ready for irradiation in ATR, scheduled to begin during the summer of 2008. Fabrication and irradiation of these fuels will provide detailed studies of actinide transmutation in support of the Global Nuclear Energy Partnership. These fuel irradiations include new fuel compositions that have never before been tested. Results from these tests will provide fundamental data on fuel irradiation performance and will advance the state of knowledge for transmutation fuels.

  8. An intrinsically safe facility for forefront research and training on nuclear technologies — Burnup and transmutation

    NASA Astrophysics Data System (ADS)

    Lomonaco, G.; Frasciello, O.; Osipenko, M.; Ricco, G.; Ripani, M.

    2014-04-01

    The currently dominant open fuel cycles have resulted in the gradual accumulation of (relatively) large quantities of highly radioactive or fertile materials in the form of depleted uranium, plutonium, minor actinides (MA) and long-lived fission products (LLFP). For low-activity wastes a heavily shielded surface repository is required. Spent fuel can be instead directly buried in deep geological repositories or reprocessed in order to separate U and Pu and eventually also MA and LLFP from other materials. These elements can be further burnt by modern reactors but not yet in sufficient quantities to slow down the steady accumulation of these materials in storage. Using ADS, the residual long-lifetime isotopes can be transmuted by nuclear reactions into shorter-lifetime isotopes again storable in surface repositories. However, in order to perform transmutations at a practical level, high-power reactors (and consequently high-power accelerators) are required; particularly, a significant transmutation can be reached not only by increasing the beam current to something of the order of a few tens of mA, but also by increasing the beam energy above 500MeV in order to reach the spallation regime. Such high-power infrastructures require intermediate test facilities with lower power and higher safety level for the investigation of their dynamics and transmutation capabilities: the ADS proposed in this study could accomplish many of these constraints.

  9. Rapid Transmutation of High-Level Nuclear Wastes in a Catalyzed Fusion-Driven System

    NASA Astrophysics Data System (ADS)

    Demir, Nesrin; Genç, Gamze; Altunok, Taner; Yapıcı, Hüseyin

    2009-03-01

    The aim of this study is to investigate the high-level waste (HLW) transmutation potential of fusion-driven transmuter (FDT) based on catalyzed D-D fusion plasma for various fuel fractions. The Minor actinide (MA) (237Np, 241Am, 243Am and 244Cm) and long-lived fission product (LLFP) (99Tc, 129I and 135Cs) nuclides discharged from high burn-up pressured water reactor-mixed oxide spent fuel are considered as the HLW. The volume fractions of the MA and LLFP are raised from 10 to 20% stepped by 2% and 10 to 80% stepped by 5%, respectively. The transmutation analyses have been performed for an operation period (OP) of up to 6 years by 75% plant factor ( η) under a first-wall neutron load ( P) of 5 MW/m2 by using two different computer codes, the XSDRNPM/SCALE4.4a neutron transport code and the MCNP4B Monte Carlo code. The numerical results bring out that the considered FDT has a high neutronic performance for an effective and rapid transmutation of MA and LLFP as well as the energy generation along the OP.

  10. Transmutation behaviour of Eurofer under irradiation in the IFMIF test facility and fusion power reactors

    NASA Astrophysics Data System (ADS)

    Fischer, U.; Simakov, S. P.; Wilson, P. P. H.

    2004-08-01

    The transmutation behaviour of the low activation steel Eurofer was analysed for irradiation simulations in the high flux test module (HFTM) of the International Fusion Material Irradiation Facility (IFMIF) neutron source and the first wall of a typical fusion power reactor (FPR) employing helium cooled lithium lead (HCLL) and pebble bed (HCPB) blankets. The transmutation calculations were conducted with the analytical and laplacian adaptive radioactivity analysis (ALARA) code and IEAF-2001 data for the IFMIF and the EASY-2003 system for the fusion power reactor (FPR) irradiations. The analyses showed that the transmutation of the main constituents of Eurofer, including iron and chromium, is not significant. Minor constituents such as Ti, V and Mn increase by 5-15% per irradiation year in the FPR and by 10-35% in the IFMIF HFTM. Other minor constituents such as B, Ta, and W show a different transmutation behaviour resulting in different elemental compositions of the Eurofer steel after high fluence irradiations in IFMIF and fusion power reactors.

  11. JAERI R and D on accelerator-based transmutation under OMEGA program

    SciTech Connect

    Takizuka, T.; Nishida, T.; Mizumoto, M.; Yoshida, H.

    1995-09-15

    The overview of the Japanese long-term research and development program on nuclide partitioning and transmutation, called ''OMEGA,'' is presented. Under this national program, major R and D activities are being carried out at JAERI, PNC, and CRIEPI. Accelerator-based transmutation study at JAERI is focused on a dedicated transmutor with a subcritical actinide-fueled subcritical core coupled with a spallation target driven by a high intensity proton accelerator. Two types of system concept, solid system and molten-salt system, are discussed. The solid system consists of sodium-cooled tungsten target and metallic actinide fuel. The molten-salt system is fueled with molten actinide chloride that acts also as a target material. The proposed plant transmutes about 250 kg of minor actinide per year, and generates enough electricity to power its own accelerator. JAERI is proposing the development of an intense proton linear accelerator ETA with 1.5 GeV-10 mA beam for engineering tests of accelerator-based transmutation. Recent achievements in the accelerator development are described.

  12. Scent Transmutation: A New Way to Teach on Chemical Equilibrium, Distillation, and Dynamic Combinatorial Chemistry

    ERIC Educational Resources Information Center

    Ji, Qing; El-Hamdi, Nadia S.; Miljanic´, Ognjen S?.

    2014-01-01

    Esters are volatile and pleasantly smelling compounds, commonly used as food additives. Using Ti(OBu)[subscript 4]-catalyzed acyl exchange, we demonstrate a scent transmutation experiment, in which two fragrant esters swap their acyl and alkoxy substituents and are, during the course of a reactive distillation, quantitatively converted into two…

  13. The Effects of Flux Spectrum Perturbation on Transmutation of Actinides: Optimizing the Production of Transcurium Isotopes

    SciTech Connect

    Hogle, Susan L; Maldonado, G Ivan; Alexander, Charles W

    2012-01-01

    This research presented herein involves the optimization of transcurium production in the High Flux Isotope Reactor at Oak Ridge National Laboratory. Due to the dependence of isotope cross sections on incoming neutron energy, the efficiency with which an isotope is transmuted is highly dependent upon the flux spectrum. There are certain energy bands in which the rate of fission of transcurium production feedstock materials is minimized, relative to the rate of non-fission absorptions. It is proposed that by perturbing the flux spectrum, it is possible to increase the amount of key isotopes, such as 249Bk and 252Cf, that are produced during a transmutation cycle, relative to the consumption of feedstock material. This optimization process is carried out by developing an iterative objective framework involving problem definition, flux spectrum and cross section analysis, simulated transmutation, and analysis of final yields and transmutation parameters. It is shown that it is possible to perturb the local flux spectrum in the transcurium target by perturbing the composition of the target. It is further shown that these perturbations are able to alter the target yields in a non-negligible way. Future work is necessary to develop the optimization framework, and identify the necessary algorithms to update the problem definition based upon progress towards the optimization goals.

  14. Heterogeneous sodium fast reactor designed for transmuting minor actinide waste isotopes into plutonium fuel

    NASA Astrophysics Data System (ADS)

    Bays, Samuel Eugene

    2008-10-01

    In the past several years there has been a renewed interest in sodium fast reactor (SFR) technology for the purpose of destroying transuranic waste (TRU) produced by light water reactors (LWR). The utility of SFRs as waste burners is due to the fact that higher neutron energies allow all of the actinides, including the minor actinides (MA), to contribute to fission. It is well understood that many of the design issues of LWR spent nuclear fuel (SNF) disposal in a geologic repository are linked to MAs. Because the probability of fission for essentially all the "non-fissile" MAs is nearly zero at low neutron energies, these isotopes act as a neutron capture sink in most thermal reactor systems. Furthermore, because most of the isotopes produced by these capture reactions are also non-fissile, they too are neutron sinks in most thermal reactor systems. Conversely, with high neutron energies, the MAs can produce neutrons by fast fission. Additionally, capture reactions transmute the MAs into mostly plutonium isotopes, which can fission more readily at any energy. The transmutation of non-fissile into fissile atoms is the premise of the plutonium breeder reactor. In a breeder reactor, not only does the non-fissile "fertile" U-238 atom contribute fast fission neutrons, but also transmutes into fissile Pu-239. The fissile value of the plutonium produced by MA transmutation can only be realized in fast neutron spectra. This is due to the fact that the predominate isotope produced by MA transmutation, Pu-238, is itself not fissile. However, the Pu-238 fission cross section is significantly larger than the original transmutation parent, predominately: Np-237 and Am-241, in the fast energy range. Also, Pu-238's fission cross section and fission-to-capture ratio is almost as high as that of fissile Pu-239 in the fast neutron spectrum. It is also important to note that a neutron absorption in Pu-238, that does not cause fission, will instead produce fissile Pu-239. Given this

  15. The Transmutation of Nuclear Waste in the Two-Zone Subcritical System Driven by High- Intensity Neutron Generator - 12098

    SciTech Connect

    Babenko, V.O.; Gulik, V.I.; Pavlovych, V.M.

    2012-07-01

    The main problems of transmutation of high-level radioactive waste (minor actinides and long-lived fission products) are considered in our work. The range of radioactive waste of nuclear power is analyzed. The conditions under which the transmutation of radioactive waste will be most effective are analyzed too. The modeling results of a transmutation of the main radioactive isotopes are presented and discussed. The transmutation of minor actinides and long-lived fission products are modeled in our work (minor actinides - Np-237, Am-241, Am-242, Am-243, Cm-244, Cm-245; long-lived fission products - I-129, Tc-99). The two-zone subcritical system is calculated with help of different neutron-physical codes (MCNP, Scale, Montebarn, Origen). The ENDF/B-VI nuclear data library used in above calculations. Thus, radioactive wastes can be divided into two main groups that need to be transmuted. The minor actinides form the first group and the long-lived fission products form the second one. For the purpose of effective transmutation these isotopes must be extracted from the spent nuclear fuel with the help of either PUREX technology or pyrometallurgical technology. The two-zone reactor system with fast and thermal regions is more effective for nuclear waste transmutation than the one-zone reactor. Modeling results show that nearly all radioactive wastes can be transmuted in the two-zone subcritical system driven by a high-intensity neutron generator with the external neutron source strength of 1.10{sup 13} n/sec. Obviously, transmutation rate will increase with a rise of the external neutron source strength. From the results above we can also see that the initial loading of radioactive isotopes into the reactor system should exceed by mass those isotopes that are finally produced. (authors)

  16. Microgamma Scan System for analyzing radial isotopic profiles of irradiated transmutation fuels

    SciTech Connect

    Bruce A. Hilton; Christopher A. McGrath

    2008-05-01

    The U. S. Global Nuclear Energy Partnership / Advanced Fuel Cycle Initiative (GNEP/AFCI) is developing metallic transmutation alloys as a fuel form to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter-lived fission products. The AFCI program has irradiated and examined eleven metallic alloy transmutation fuel specimens to evaluate the feasibility of actinide transmutation in advanced sodium-cooled fast reactors and thermal reactor implementation. Initial results of postirradiation examinations indicated the irradiation performance of the actinide-bearing compositions is similar to uranium-plutonium-zirconium ternary metallic alloy fuels (U-xPu-10Zr). Further studies to characterize radial burnup profile, constituent migration, and fuel cladding chemical interaction (FCCI) are in progress. A microgamma scan system is being developed to analyze the radial distribution of fission products, such as Cs-137, Cs-134, Ru-106, and Zr-95, in irradiated fuel cross-sections. The microgamma scan system consists of a set of indexed sample collimator blocks and a sample holder, which interfaces with the INL Analytical Laboratory Hot Cell (ALHC) Gamma Scan System high purity germanium detector, multichannel analyzer, and removable collimators. The microgamma scan results will be used to evaluate radial burnup profile, cesium migration to the sodium bond and constituent migration within the fuel. These data will further clarify the comparative irradiation performance of actinide-bearing metallic transmutation fuel forms and uranium-plutonium-zirconium alloys. Preliminary measurements of the microgamma scan system will be discussed. A simplified model of the microgamma scan system was developed in MCNP and used to investigate the system performance and to interpret data from the scoping studies. Recommendations for improving the MCGS analyses are discussed.

  17. Low Energy Nuclear Transmutation in Condensed Matter Induced by D2 Gas Permeation Through pd Complexes:. Correlation Between Deuterium Flux and Nuclear Products

    NASA Astrophysics Data System (ADS)

    Iwamura, Y.; Itoh, T.; Sakano, M.; Sakai, S.; Kuribayashi, S.

    2005-12-01

    Observations of low energy nuclear reactions induced by D2 gas permeation through Pd complexes (Pd/CaO/Pd) were presented at ICCF-91 and in a paper2 published in the Japanese Journal of Applied Physics. When Cs was added on the surface of a Pd complex, Pr emerged on the surface while Cs decreased after the Pd complex was subjected to D2 gas permeation. When Sr was added to the surface, Mo emerged while the Sr decreased after D2 gas permeation. The isotopic composition of the detected Mo was different from the natural abundance. In this paper, recent progress of our research is described. The detected Pr was confirmed by various methods such as TOF-SIMS, XANES, X-ray Fluorescence Spectrometry and ICP-MS. Analysis of the depth profile of Pr indicated that a very thin surface region up to 100 Å was the active transmutation zone. Many experimental results showed that the quantity of Pr was proportional to the deuterium flux through Pd complex. The cross-section of transmutation of Cs into Pr can be roughly estimated at 1 barn if we consider the deuterium flux as an ultra low energy deuteron beam.

  18. Parametric Studies on Plutonium Transmutation Using Uranium-Free Fuels in Light Water Reactors

    SciTech Connect

    Shelley, Afroza; Akie, Hiroshi; Takano, Hideki; Sekimoto, Hiroshi

    2000-08-15

    To compare the once-through use of U-free fuels for plutonium burnup in light water reactors (LWRs), plutonium transmutation, minor actinide (MA) and long-life fission product (LLFP) buildup and radiotoxicity hazards were compared for PuO{sub 2} + ZrO{sub 2} (rock-like oxide: ROX) and PuO{sub 2} + ThO{sub 2} (thorium oxide: TOX) fuels, loaded in a soft-to-hard neutron spectrum LWR core (a moderator-to-fuel volume ratio V{sub m}/V{sub f} is from 0.5 to 3.0). For better understanding and proper improvement of the reactivity coefficient problem of ROX, the fuel temperature coefficient, the void coefficient, and the delayed neutron fraction were also studied. A mixed-oxide (MOX)-fueled LWR was considered for reference purposes.From the result of the cell burnup calculation, ROX fuel transmutes 90% of net initially loaded weapons-grade Pu, and 2.5% of initially loaded Pu is converted to MAs when V{sub m}/V{sub f} is 2.0 and discharge burnup in effective full-power days is equivalent to that of 33 GWd/t in MOX fuel. Reactor-grade Pu-based ROX fuel transmutes 80% of net initially loaded Pu, and 6.7% of initially loaded Pu converts to MAs with the same condition as the weapons-grade Pu ROX fuel. TOX fuel also has a good Pu transmutation capability, but the {sup 233}U production amount is approximately a half of the fissile Pu transmutation amount. The MA production amount in TOX fuel is lower than that in MOX and ROX fuels. The LLFP production amount in ROX fuel is lower than that in MOX and TOX fuels. The radiotoxicity hazard of ROX spent fuel is lower compared to that in TOX and MOX spent fuels.The thermal neutron energy region is important in ROX fuel for fuel temperature coefficient and void coefficient problems. From these calculations, 15 to 20% {sup 232}Th-added ROX fuel seems the best to use as a once-through Pu-burning fuel compared to TOX and MOX fuels in conventional LWRs, because of its higher Pu transmutation, lower radiotoxicity hazard.

  19. The optimization of an AP1000 fuel assembly for the transmutation of plutonium and minor actinides

    NASA Astrophysics Data System (ADS)

    Washington, Jeremy A.

    The average nuclear power plant produces twenty metric tons of used nuclear fuel per year, containing approximately 95 wt% uranium, 1 wt% plutonium, and 4 wt% fission products and transuranic elements. Fast reactors are a preferred option for the transmutation of plutonium and minor actinides; however, an optimistic deployment time of at least 20 years indicates a need for a near-term solution. The goal of this thesis is to examine the potential of light water reactors for plutonium and minor actinides transmutation as a near-term solution. This thesis screens the available nuclear isotope database to identify potential absorbers as coatings on a transmutation fuel in a light water reactor. A spectral shift absorber coating tunes the neutron energy spectrum experienced by the underlying target fuel. Eleven different spectral shift absorbers (B4C, CdO, Dy2O3, Er 2O3, Eu2O3, Gd2O3, HfO2, In2O3, Lu2O3, Sm2O3, and TaC) have been selected for further evaluation. A model developed using the NEWT module of SCALE 6.1 code provided performance data for the burnup of the target fuel rods. Irradiation of the target fuels occurs in a Westinghouse 17x17 XL Robust Fuel Assembly over a 1400 Effective Full Power Days (EFPD) interval. The fuels evaluated in this thesis include PuO2, Pu3Si2, PuN, MOX, PuZrH, PuZrHTh, PuZrO 2, and PuUZrH. MOX (5 wt% PuO2), Pu0.31ZrH 1.6Th1.08, and PuZrO2MgO (8 wt%) are selected for detailed analysis in a multi-pin transmutation assembly. A coupled model optimized the resulting transmutation fuel elements. The optimization considered three stages of fuel assemblies containing target fuel pins. The first stage optimized four target fuel pins adjacent to the central instrumentation channel. The second stage evaluated a variety of assemblies with multiple target fuel pins and the third stage re-optimized target fuel pins in the second-stage assembly. A PuZrO2MgO (8 wt%) target fuel with a coating of Lu 2O3 resulted in the greatest reduction in curium-244

  20. Evaluation of transuranium isotopes inventory for Candu/ACR standard and SEU spent fuel and the possibility to transmute them

    SciTech Connect

    Ghizdeanu, Elena Nineta; Pavelescu, Alexandru; Balaceanu, Victoria

    2007-07-01

    Available in abstract form only. Full text of publication follows: The main disadvantage of nuclear energy is the quantity of long lived radioactive waste produced in a NPP. Transmutation could be one of the solutions to reduce it. Waste transmutation will require a suitable deployment of techniques for spent fuel reprocessing. At present, reprocessing is done by aqueous methods that are very efficient for Pu separation (up to 99.9%). For transmutation applications, new partitioning processes must be developed for minor actinides separation from the high level waste. Although these processes are still very much at the research stage, industrial scale-up will result in the deployment of new, more specific separation techniques for transmutation applications. Partitioning and Transmutation (P and T) techniques could contribute to reduce the radioactive inventory and its associated radio-toxicity. Scientists are looking for ways to drastically reduce both the mass and the radio-toxicity of the nuclear waste to be stored in a deep geological repository, and to reduce the time needed to reach the radioactivity level of the raw material originally used to produce energy. The first stage in the transmutation process is the isotopes inventory formed in the spent fuel. In this paper is made an intercomparison evaluation using WIMS 5B.12 and ORIGEN computer codes. Using these two codes, there is evaluated the isotopes released by a fuel standard from a Candu reactor. Moreover, there is simulated an inventory released by a Candu-SEU reactor and an ACR reactor. (authors)

  1. Implications of transmutation on the defect chemistry in crystalline waste forms

    NASA Astrophysics Data System (ADS)

    Uberuaga, B. P.; Jiang, C.; Stanek, C. R.; Sickafus, K. E.; Marks, N. A.; Carter, D. J.; Rohl, A. L.

    2010-10-01

    Radioactive decay within the solid state creates chemical environments which are typically incommensurate with the initial host structure. Using a combined theoretical and computational approach, we discuss this 'transmutation problem' in the context of the short-lived fission products Cs-137 and Sr-90. We show how a Kröger-Vink treatment is insufficient for understanding defects arising from transmutation, and present density functional theory data for chemical evolution within two prototypical hosts, CsCl and SrTiO 3. While the latter has a strong driving force for phase separation with increasing Zr content, the Cs(Ba)Cl system is surprisingly stable. The sharp difference between these two findings points to the need for better understanding of novel chemistry in nuclear waste forms.

  2. A Thorium/Uranium fuel cycle for an advanced accelerator transmutation of nuclear waste concept

    SciTech Connect

    Truebenbach, M.T.; Henderson, D.L.; Venneri, F.

    1993-12-31

    Utilizing the high thermal neutron flux of an accelerator driven transmuter to drive a Thorium-Uranium fuel production scheme, it is possible to produce enough energy in the transmuter not only to power the accelerator, but to have enough excess power available for commercial use. A parametric study has been initiated to determine the ``optimum`` equilibrium operation point in terms of the minimization of the equilibrium actinide inventory and the fuel {alpha} for various residence times in the High Flux Region (HFR) and in the Low Flux Region (LFR). For the cases considered, the ``optimum`` equilibrium operation point was achieved for a HFR residence time of 45 days and a LFR residence time of 60 days. For this case, the total actinide inventory in the system is about 20 tonnes and the fuel {alpha} approximately 1.46.

  3. A Subcritical, Gas-Cooled Fast Transmutation Reactor with a Fusion Neutron Source

    SciTech Connect

    Stacey, W.M.; Beavers, V.L.; Casino, W.A.; Cheatham, J.R.; Friis, Z.W.; Green, R.D.; Hamilton, W.R.; Haufler, K.W.; Hutchinson, J.D.; Lackey, W.J.; Lorio, R.A.; Maddox, J.W.; Mandrekas, J.; Manzoor, A.A.; Noelke, C.A.; Oliveira, C. de; Park, M.; Tedder, D.W.; Terry, M.R.; Hoffman, E.A.

    2005-05-15

    A design is presented for a subcritical, He-cooled fast reactor, driven by a tokamak D-T fusion neutron source, for the transmutation of spent nuclear fuel (SNF). The reactor is fueled with coated transuranic (TRU) particles and is intended for the deep-burn (>90%) transmutation of the TRUs in SNF without reprocessing of the coated fuel particles. The reactor design is based on the materials, fuel, and separations technologies under near-term development in the U.S. Department of Energy (DOE) Nuclear Energy Program and on the plasma physics and fusion technologies under near-term development in the DOE Fusion Energy Sciences Program, with the objective of intermediate-term ({approx}2040) deployment. The physical and performance characteristics and research and development requirements of such a reactor are described.

  4. Hydrogen bond disruption in DNA base pairs from (14)C transmutation.

    PubMed

    Sassi, Michel; Carter, Damien J; Uberuaga, Blas P; Stanek, Christopher R; Mancera, Ricardo L; Marks, Nigel A

    2014-09-01

    Recent ab initio molecular dynamics simulations have shown that radioactive carbon does not normally fragment DNA bases when it decays. Motivated by this finding, density functional theory and Bader analysis have been used to quantify the effect of C → N transmutation on hydrogen bonding in DNA base pairs. We find that (14)C decay has the potential to significantly alter hydrogen bonds in a variety of ways including direct proton shuttling (thymine and cytosine), thermally activated proton shuttling (guanine), and hydrogen bond breaking (cytosine). Transmutation substantially modifies both the absolute and relative strengths of the hydrogen bonding pattern, and in two instances (adenine and cytosine), the density at the critical point indicates development of mild covalent character. Since hydrogen bonding is an important component of Watson-Crick pairing, these (14)C-induced modifications, while infrequent, may trigger errors in DNA transcription and replication. PMID:25127298

  5. Application of neutron transmutation doping method to initially p-type silicon material.

    PubMed

    Kim, Myong-Seop; Kang, Ki-Doo; Park, Sang-Jun

    2009-01-01

    The neutron transmutation doping (NTD) method was applied to the initially p-type silicon in order to extend the NTD applications at HANARO. The relationship between the irradiation neutron fluence and the final resistivity of the initially p-type silicon material was investigated. The proportional constant between the neutron fluence and the resistivity was determined to be 2.3473x10(19)nOmegacm(-1). The deviation of the final resistivity from the target for almost all the irradiation results of the initially p-type silicon ingots was at a range from -5% to 2%. In addition, the burn-up effect of the boron impurities, the residual (32)P activity and the effect of the compensation characteristics for the initially p-type silicon were studied. Conclusively, the practical methodology to perform the neutron transmutation doping of the initially p-type silicon ingot was established. PMID:19318259

  6. The role of Z-pinch fusion transmutation of waste in the nuclear fuel cycle.

    SciTech Connect

    Smith, James Dean; Drennen, Thomas E.; Rochau, Gary Eugene; Martin, William Joseph; Kamery, William; Phruksarojanakun, Phiphat; Grady, Ryan; Cipiti, Benjamin B.; Wilson, Paul Philip Hood; Mehlhorn, Thomas Alan; Guild-Bingham, Avery; Tsvetkov, Pavel Valeryevich

    2007-10-01

    The resurgence of interest in reprocessing in the United States with the Global Nuclear Energy Partnership has led to a renewed look at technologies for transmuting nuclear waste. Sandia National Laboratories has been investigating the use of a Z-Pinch fusion driver to burn actinide waste in a sub-critical reactor. The baseline design has been modified to solve some of the engineering issues that were identified in the first year of work, including neutron damage and fuel heating. An on-line control feature was added to the reactor to maintain a constant neutron multiplication with time. The transmutation modeling effort has been optimized to produce more accurate results. In addition, more attention was focused on the integration of this burner option within the fuel cycle including an investigation of overall costs. This report presents the updated reactor design, which is able to burn 1320 kg of actinides per year while producing 3,000 MWth.

  7. High-power proton linac for transmuting the long-lived fission products in nuclear waste

    SciTech Connect

    Lawrence, G.P.

    1991-01-01

    High power proton linacs are being considered at Los Alamos as drivers for high-flux spallation neutron sources that can be used to transmute the troublesome long-lived fission products in defense nuclear waste. The transmutation scheme being studied provides a high flux (> 10{sup 16}/cm{sup 2}{minus}s) of thermal neutrons, which efficiently converts fission products to stable or short-lived isotopes. A medium-energy proton linac with an average beam power of about 110 MW can burn the accumulated Tc99 and I129 inventory at the DOE's Hanford Site within 30 years. Preliminary concepts for this machine are described. 3 refs., 5 figs., 2 tabs.

  8. TRANSMUTATIONS IN SiC IRRADIATED IN ARIES-IV FIRST WALL

    SciTech Connect

    Heinisch, Howard L.

    2001-04-01

    The change in concentrations of elements due to transmutations resulting from neutron irradiation in the first wall of the ARIES-IV conceptual fusion energy device were determined as a function of neutron dose. SiC burns out at a rate of about 0.5% per effective full power year. The largest impurity concentration is that of He, but several other elements burn in at rates of hundreds of appm/efpy.

  9. Minor actinide transmutation in thorium and uranium matrices in heavy water moderated reactors

    SciTech Connect

    Bhatti, Zaki; Hyland, B.; Edwards, G.W.R.

    2013-07-01

    The irradiation of Th{sup 232} breeds fewer of the problematic minor actinides (Np, Am, Cm) than the irradiation of U{sup 238}. This characteristic makes thorium an attractive potential matrix for the transmutation of these minor actinides, as these species can be transmuted without the creation of new actinides as is the case with a uranium fuel matrix. Minor actinides are the main contributors to long term decay heat and radiotoxicity of spent fuel, so reducing their concentration can greatly increase the capacity of a long term deep geological repository. Mixing minor actinides with thorium, three times more common in the Earth's crust than natural uranium, has the additional advantage of improving the sustainability of the fuel cycle. In this work, lattice cell calculations have been performed to determine the results of transmuting minor actinides from light water reactor spent fuel in a thorium matrix. 15-year-cooled group-extracted transuranic elements (Np, Pu, Am, Cm) from light water reactor (LWR) spent fuel were used as the fissile component in a thorium-based fuel in a heavy water moderated reactor (HWR). The minor actinide (MA) transmutation rates, spent fuel activity, decay heat and radiotoxicity, are compared with those obtained when the MA were mixed instead with natural uranium and taken to the same burnup. Each bundle contained a central pin containing a burnable neutron absorber whose initial concentration was adjusted to have the same reactivity response (in units of the delayed neutron fraction β) for coolant voiding as standard NU fuel. (authors)

  10. Neutron Transmutation Doped (NTD) germanium thermistors for sub-mm bolometer applications

    NASA Technical Reports Server (NTRS)

    Haller, E. E.; Itoh, K. M.; Beeman, J. W.

    1996-01-01

    Recent advances in the development of neutron transmutation doped (NTD) semiconductor thermistors fabricated from natural and controlled isotopic composition germanium are reported. The near ideal doping uniformity that can be achieved with the NTD process, the device simplicity of NTD Ge thermistors and the high performance of cooled junction field effect transistor preamplifiers led to the widespread acceptance of these thermal sensors in ground-based, airborne and spaceborne radio telescopes. These features made possible the development of efficient bolometer arrays.

  11. Depth uniformity of electrical properties and doping limitation in neutron-transmutation-doped semi-insulating GaAs

    SciTech Connect

    Satoh, M.; Kuriyama, K. ); Kawakubo, T. )

    1990-04-01

    Depth uniformity of electrical properties has been evaluated for neutron-transmutation-doped (NTD), semi-insulating GaAs irradiated with thermal neutrons of 1.5{times}10{sup 18} cm{sup {minus}2} by the van der Pauw method combined with iterative etching of the surface. In NTD-GaAs wafers (thickness {similar to}410 {mu}m) annealed for 30 min at 700 {degree}C, the depth profiles of the resistivity, the carrier concentration, and the Hall mobility show constant values of 1{times}10{sup {minus}2} {Omega} cm, 2.0{times}10{sup 17} cm{sup {minus}3}, and 3100 cm{sup 2}/V s, respectively, within an experimental error of 5%. In an annealing process, the redistribution and/or the segregation of NTD impurities is not observed. We also discuss the limitations of low-level NTD in semi-insulating GaAs. It is suggested that the activation of the NTD-impurities below {similar to}1{times}10{sup 16} cm{sup {minus}3} is mainly restricted by the presence of the midgap electron trap (EL2).

  12. Status of development of actinide blanket processing flowsheets for accelerator transmutation of nuclear waste

    SciTech Connect

    Dewey, H.J.; Jarvinen, G.D.; Marsh, S.F.; Schroeder, N.C.; Smith, B.F.; Villarreal, R.; Walker, R.B.; Yarbro, S.L.; Yates, M.A.

    1993-09-01

    An accelerator-driven subcritical nuclear system is briefly described that transmutes actinides and selected long-lived fission products. An application of this accelerator transmutation of nuclear waste (ATW) concept to spent fuel from a commercial nuclear power plant is presented as an example. The emphasis here is on a possible aqueous processing flowsheet to separate the actinides and selected long-lived fission products from the remaining fission products within the transmutation system. In the proposed system the actinides circulate through the thermal neutron flux as a slurry of oxide particles in heavy water in two loops with different average residence times: one loop for neptunium and plutonium and one for americium and curium. Material from the Np/Pu loop is processed with a short cooling time (5-10 days) because of the need to keep the total actinide inventory, low for this particular ATW application. The high radiation and thermal load from the irradiated material places severe constraints on the separation processes that can be used. The oxide particles are dissolved in nitric acid and a quarternary, ammonium anion exchanger is used to extract neptunium, plutonium, technetium, and palladium. After further cooling (about 90 days), the Am, Cm and higher actinides are extracted using a TALSPEAK-type process. The proposed operations were chosen because they have been successfully tested for processing high-level radioactive fuels or wastes in gram to kilogram quantities.

  13. Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux

    DOEpatents

    Bowman, C.D.

    1992-11-03

    Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux. High thermal neutron fluxes generated from the action of a high power proton accelerator on a spallation target allows the efficient burn-up of higher actinide nuclear waste by a two-step process. Additionally, rapid burn-up of fission product waste for nuclides having small thermal neutron cross sections, and the practicality of small material inventories while achieving significant throughput derive from employment of such high fluxes. Several nuclear technology problems are addressed including 1. nuclear energy production without a waste stream requiring storage on a geological timescale, 2. the burn-up of defense and commercial nuclear waste, and 3. the production of defense nuclear material. The apparatus includes an accelerator, a target for neutron production surrounded by a blanket region for transmutation, a turbine for electric power production, and a chemical processing facility. In all applications, the accelerator power may be generated internally from fission and the waste produced thereby is transmuted internally so that waste management might not be required beyond the human lifespan.

  14. Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux

    DOEpatents

    Bowman, Charles D.

    1992-01-01

    Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux. High thermal neutron fluxes generated from the action of a high power proton accelerator on a spallation target allows the efficient burn-up of higher actinide nuclear waste by a two-step process. Additionally, rapid burn-up of fission product waste for nuclides having small thermal neutron cross sections, and the practicality of small material inventories while achieving significant throughput derive from employment of such high fluxes. Several nuclear technology problems are addressed including 1. nuclear energy production without a waste stream requiring storage on a geological timescale, 2. the burn-up of defense and commercial nuclear waste, and 3. the production of defense nuclear material. The apparatus includes an accelerator, a target for neutron production surrounded by a blanket region for transmutation, a turbine for electric power production, and a chemical processing facility. In all applications, the accelerator power may be generated internally from fission and the waste produced thereby is transmuted internally so that waste management might not be required beyond the human lifespan.

  15. Effects of TRU Distributions of Electron Accelerator-Driven Subcritical Core Systems on Transmutation

    SciTech Connect

    Yodersmith, Stephen; Yim, Man-Sung

    2007-07-01

    As part of the effort to investigate the use of an electron accelerator driven system for TRU transmutation, the effects of TRU distributions in the core on transmuter system performance was examined in this paper. The system performance examined includes the transmutation and system power efficiency and changes in power peaking. The transmutation benefits of the system were determined with the introduction of a new parameter, the Transmutation System Effectiveness Parameter (TSEP). TSEP combines the decay heat and radioactivity results into one single parameter that compares the ability of the system to reduce the radioactivity and decay heat of the loaded TRUs. The electron ADS was modeled by using MCNPX and MONTEBURNS as a fast spectrum, Na cooled reactor loosely based on the advanced liquid metal reactor (ALMR) design. NJOY was used to process the cross sections at the desired temperatures. The fuel was a TRUZr alloy contained within an HT-9 SS cladding. The subcritical reactor contained four different fuel zones with an equal number of fuel assemblies in each region, each containing one of the four TRU elements: Np, Pu, Cm, Am. Tungsten was used for the target system. The electron ADS was assumed to operate at 500 MWth over a 24 month cycle. Results showed that different distribution patterns had a very insignificant effect on the total radioactivity reduction, the total decay heat reduction, and the TRU radiotoxicity reduction. With respect to the TSEP parameter, the calculation results revealed a much stronger dependence on TRU distributions. It seemed that TSEP accurately reflected and penalized the effectiveness of the system for the fission product production. With respect to examining the k{sub eff} over the cycle, a drastic difference was observed between the cases when Pu is located in the inner most region and the rest of the patterns. The k{sub eff} for the Pu in the inner most region cases decreased at a much faster rate than did the rest therefore

  16. The technical and economic impact of minor actinide transmutation in a sodium fast reactor

    SciTech Connect

    Gautier, G. M.; Morin, F.; Dechelette, F.; Sanseigne, E.; Chabert, C.

    2012-07-01

    Within the frame work of the French National Act of June 28, 2006 pertaining to the management of high activity, long-lived radioactive waste, one of the proposed processes consists in transmuting the Minor Actinides (MA) in the radial blankets of a Sodium Fast Reactor (SFR). With this option, we may assess the additional cost of the reactor by comparing two SFR designs, one with no Minor Actinides, and the other involving their transmutation. To perform this exercise, we define a reference design called SFRref, of 1500 MWe that is considered to be representative of the Reactor System. The SFRref mainly features a pool architecture with three pumps, six loops with one steam generator per loop. The reference core is the V2B core that was defined by the CEA a few years ago for the Reactor System. This architecture is designed to meet current safety requirements. In the case of transmutation, for this exercise we consider that the fertile blanket is replaced by two rows of assemblies having either 20% of Minor Actinides or 20% of Americium. The assessment work is performed in two phases. - The first consists in identifying and quantifying the technical differences between the two designs: the reference design without Minor Actinides and the design with Minor Actinides. The main differences are located in the reactor vessel, in the fuel handling system and in the intermediate storage area for spent fuel. An assessment of the availability is also performed so that the impact of the transmutation can be known. - The second consists in making an economic appraisal of the two designs. This work is performed using the CEA's SEMER code. The economic results are shown in relative values. For a transmutation of 20% of MA in the assemblies (S/As) and a hypothesis of 4 kW allowable for the washing device, there is a large external storage demanding a very long cooling time of the S/As. In this case, the economic impact may reach 5% on the capital part of the Levelized Unit

  17. On the use of a molten salt fast reactor to apply an idealized transmutation scenario for the nuclear phase out.

    PubMed

    Merk, Bruno; Rohde, Ulrich; Glivici-Cotruţă, Varvara; Litskevich, Dzianis; Scholl, Susanne

    2014-01-01

    In the view of transmutation of transuranium (TRU) elements, molten salt fast reactors (MSFRs) offer certain advantages compared to solid fuelled reactor types like sodium cooled fast reactors (SFRs). In the first part these advantages are discussed in comparison with the SFR technology, and the research challenges are analyzed. In the second part cycle studies for the MSFR are given for different configurations--a core with U-238 fertile, a fertile free core, and a core with Th-232 as fertile material. For all cases, the transmutation potential is determined and efficient transmutation performance for the case with thorium as a fertile material as well as for the fertile free case is demonstrated and the individual advantages are discussed. The time evolution of different important isotopes is analyzed. In the third part a strategy for the optimization of the transmutation efficiency is developed. The final aim is dictated by the phase out decision of the German government, which requests to put the focus on the determination of the maximal transmutation efficiency and on an as much as possible reduced leftover of transuranium elements at the end of the reactor life. This minimal leftover is achieved by a two step procedure of a first transmuter operation phase followed by a second deep burning phase. There the U-233, which is bred in the blanket of the core consisting of thorium containing salt, is used as feed. It is demonstrated, that transmutation rates up to more than 90% can be achieved for all transuranium isotopes, while the production of undesired high elements like californium is very limited. Additionally, the adaptations needed for the simulation of a MSFR, and the used tool HELIOS 1.10 is described. PMID:24690768

  18. On the Use of a Molten Salt Fast Reactor to Apply an Idealized Transmutation Scenario for the Nuclear Phase Out

    PubMed Central

    Merk, Bruno; Rohde, Ulrich; Glivici-Cotruţă, Varvara; Litskevich, Dzianis; Scholl, Susanne

    2014-01-01

    In the view of transmutation of transuranium (TRU) elements, molten salt fast reactors (MSFRs) offer certain advantages compared to solid fuelled reactor types like sodium cooled fast reactors (SFRs). In the first part these advantages are discussed in comparison with the SFR technology, and the research challenges are analyzed. In the second part cycle studies for the MSFR are given for different configurations – a core with U-238 fertile, a fertile free core, and a core with Th-232 as fertile material. For all cases, the transmutation potential is determined and efficient transmutation performance for the case with thorium as a fertile material as well as for the fertile free case is demonstrated and the individual advantages are discussed. The time evolution of different important isotopes is analyzed. In the third part a strategy for the optimization of the transmutation efficiency is developed. The final aim is dictated by the phase out decision of the German government, which requests to put the focus on the determination of the maximal transmutation efficiency and on an as much as possible reduced leftover of transuranium elements at the end of the reactor life. This minimal leftover is achieved by a two step procedure of a first transmuter operation phase followed by a second deep burning phase. There the U-233, which is bred in the blanket of the core consisting of thorium containing salt, is used as feed. It is demonstrated, that transmutation rates up to more than 90% can be achieved for all transuranium isotopes, while the production of undesired high elements like californium is very limited. Additionally, the adaptations needed for the simulation of a MSFR, and the used tool HELIOS 1.10 is described. PMID:24690768

  19. LIFE Materials: Phase Formation and Transformations in Transmutation Fuel Materials for the LIFE Engine Part I - Path Forward Volume 3

    SciTech Connect

    Turchi, P A; Kaufman, L; Fluss, M

    2008-12-19

    The current specifications of the LLNL fusion-fission hybrid proposal, namely LIFE, impose severe constraints on materials, and in particular on the nuclear fissile or fertile nuclear fuel and its immediate environment. This constitutes the focus of the present report with special emphasis on phase formation and phase transformations of the transmutation fuel and their consequences on particle and pebble thermal, chemical, and mechanical integrities. We first review the work that has been done in recent years to improve materials properties under the Gen-IV project, and with in particular applications to HTGR and MSR, and also under GNEP and AFCI in the USA. Our goal is to assess the nuclear fuel options that currently exist together with their issues. Among the options, it is worth mentioning TRISO, IMF, and molten salts. The later option will not be discussed in details since an entire report (Volume 8 - Molten-salt Fuels) is dedicated to it. Then, in a second part, with the specific LIFE specifications in mind, the various fuel options with their most critical issues are revisited with a path forward for each of them in terms of research, both experimental and theoretical. Since LIFE is applicable to very high burn-up of various fuels, distinctions will be made depending on the mission, i.e., energy production or incineration. Finally a few conclusions are drawn in terms of the specific needs for integrated materials modeling and the in depth knowledge on time-evolution thermo-chemistry that controls and drastically affects the performance of the nuclear materials and their immediate environment. Although LIFE demands materials that very likely have not yet been fully optimized, the challenges are not insurmountable, and a well concerted experimental-modeling effort should lead to dramatic advances that should well serve other fission programs such as Gen-IV, GNEP, AFCI as well as the international fusion program, ITER.

  20. Transmutation Analysis of Enriched Uranium and Deep Burn High Temperature Reactors

    SciTech Connect

    Michael A. Pope

    2012-07-01

    High temperature reactors (HTRs) have been under consideration for production of electricity, process heat, and for destruction of transuranics for decades. As part of the transmutation analysis efforts within the Fuel Cycle Research and Development (FCR&D) campaign, a need was identified for detailed discharge isotopics from HTRs for use in the VISION code. A conventional HTR using enriched uranium in UCO fuel was modeled having discharge burnup of 120 GWd/MTiHM. Also, a deep burn HTR (DB-HTR) was modeled burning transuranic (TRU)-only TRU-O2 fuel to a discharge burnup of 648 GWd/MTiHM. For each of these cases, unit cell depletion calculations were performed with SCALE/TRITON. Unit cells were used to perform this analysis using SCALE 6.1. Because of the long mean free paths (and migration lengths) of neutrons in HTRs, using a unit cell to represent a whole core can be non-trivial. The sizes of these cells were first set by using Serpent calculations to match a spectral index between unit cell and whole core domains. In the case of the DB-HTR, the unit cell which was arrived at in this way conserved the ratio of fuel to moderator found in a single block of fuel. In the conventional HTR case, a larger moderator-to-fuel ratio than that of a single block was needed to simulate the whole core spectrum. Discharge isotopics (for 500 nuclides) and one-group cross-sections (for 1022 nuclides) were delivered to the transmutation analysis team. This report provides documentation for these calculations. In addition to the discharge isotopics, one-group cross-sections were provided for the full list of 1022 nuclides tracked in the transmutation library.

  1. Radioactive Waste Partitioning and Transmutation within Advanced Fuel Cycles: Achievements and Challenges

    SciTech Connect

    M. Salvatores; G. Palmiotti

    2011-01-01

    If nuclear power should become a sustainable source of energy, a safe, robust and acceptable solution must be pursued for existing and projected inventories of high-activity, long-lived radioactive waste. Remarkable progress in the last two decades has been made in the field of geological disposal. Some countries have reached important milestones and geological disposal (of spent fuel) is expected to start in 2020 in Finland and in 2022 in Sweden and in fact the licensing of the geological repositories in both countries is now entering into their final phases. In France disposal of Intermediate Level Wastes (ILW) and vitrified High Level Wastes (HLW) is expected to start around 2025, according to the roadmap defined by a Parliament Act in 2006. In this context, transmutation of part of the waste through use of advanced fuel cycles, probably feasible in the coming decades, has the potential of reducing the burden on the geological repository. This article presents the physical principle of transmutation and reviews several strategies of P&T (Partitioning and Transmutation). Many recent studies have demonstrated that the impact of P&T on geological disposal concepts is not overwhelmingly high. However, by reducing waste heat production a more efficient utilization of repository space is likely. Moreover, even if radionuclide release from the waste to the environment and related calculated doses to the population are only partially reduced by P&T, it is important to point out that a clear reduction of the actinide inventory in the High Level Waste definitely reduces risks arising from less probable evolutions of a repository, i.e. increase of actinide mobility in certain geochemical situations and radiological impact by human intrusion.

  2. Radioactive waste partitioning and transmutation within advanced fuel cycles: Achievements and challenges

    NASA Astrophysics Data System (ADS)

    Salvatores, M.; Palmiotti, G.

    2011-01-01

    If nuclear power becomes a sustainable source of energy, a safe, robust, and acceptable solution must be pursued for existing and projected inventories of high-activity, long-lived radioactive waste. Remarkable progress in the field of geological disposal has been made in the last two decades. Some countries have reached important milestones, and geological disposal (of spent fuel) is expected to start in 2020 in Finland and in 2022 in Sweden. In fact, the licensing of the geological repositories in both countries is now entering into its final phase. In France, disposal of intermediate-level waste (ILW) and vitrified high-level waste (HLW) is expected to start around 2025, according to the roadmap defined by an Act of Parliament in 2006. In this context, transmutation of part of the waste through use of advanced fuel cycles, probably feasible in the coming decades, can reduce the burden on the geological repository. This article presents the physical principle of transmutation and reviews several strategies of partitioning and transmutation (P&T). Many recent studies have demonstrated that the impact of P&T on geological disposal concepts is not overwhelmingly high. However, by reducing waste heat production, a more efficient utilization of repository space is likely. Moreover, even if radionuclide release from the waste to the environment and related calculated doses to the population are only partially reduced by P&T, it is important to point out that a clear reduction of the actinide inventory in the HLW definitely reduces risks arising from less probable evolutions of a repository (i.e., an increase of actinide mobility in certain geochemical situations and radiological impact by human intrusion).

  3. A Los Alamos concept for accelerator transmutation of waste and energy production (ATW)

    SciTech Connect

    Not Available

    1990-12-31

    This document contains the diagrams presented at the ATW (Accelerator Transmutation of Waste and Energy Production) External Review, December 10-12, 1990, held at Los Alamos National Laboratory. Included are the charge to the committee and the presentations for the committee`s review. Topics of the presentations included an overview of the concept, LINAC technology, near-term application -- high-level defense wastes (intense thermal neutron source, chemistry and materials), advanced application of the ATW concept -- fission energy without a high-level waste stream (overview, advanced technology, and advanced chemistry), and a summary of the research issues.

  4. Repository size for deep geological disposal of partitioning and transmutation high level waste

    SciTech Connect

    Nishihara, Kenji; Nakayama, Shinichi; Oigawa, Hiroyuki

    2007-07-01

    In order to reveal the impact of the partitioning and transmutation (PT) technology on the geological disposal, we investigated the production and disposal of the radioactive wastes from the PT facilities including the dry reprocessing for the spent fuel from accelerator-driven system. After classifying the PT wastes according to the heat generations, the emplacement configurations in the repository were assumed for each group based on the several disposal concepts proposed for the conventional glass waste form. Then, the sizes of the repositories represented by the vault length, emplacement area and excavation volume were estimated. The repository sizes were reduced by PT technology for all disposal concepts. (authors)

  5. Simulation for thick-target yields of transmutation reactions on radioactive targets, based on inverse kinematics

    NASA Astrophysics Data System (ADS)

    Ebata, Shuichiro; Aikawa, Masayuki; Imai, Shotaro

    2016-06-01

    To dispose of long-lived fission products (LLFP) ejected from nuclear reactor plants is one of the most important tasks on nuclear physics and engineering. The experiments with the radiative target are limited, due to the high radioactivity and chemical property of the target. In consequence, the nuclear reaction data for LLFP are insufficient. In this work, we propose a feasible method to obtain the data for radiative targets using inverse kinematics and simulate specific systems to evaluate the thick-target yields of the nuclear transmutation reactions for LLFP.

  6. Sensitvity and Uncertainty Analysis for a Minor-actinide Transmuter with JENDL-4.0

    NASA Astrophysics Data System (ADS)

    Iwamoto, H.; Nishihara, K.; Sugawara, T.; Tsujimoto, K.

    2014-04-01

    A sensitivity and uncertainty analysis was performed for the minor-actinide transmuter proposed by the Japan Atomic Energy Agency with JENDL-4.0. Analysis with sensitivity coefficients and the JENDL-4.0 covariance data showed that the covariances of the capture cross sections and fission-related parameters of MAs and Pu isotopes have considerable impact on the uncertainties of reactor physics parameters, and covariances of the inelastic scattering cross section of lead-bismuth eutectic (LBE) materials significantly affect the uncertainty of coolant-void reactivity.

  7. Neutron transmutation doped (Ntd) germanium thermistors for sub-Mm bolometer applications

    SciTech Connect

    Haller, E.E. |; Itoh, K.M.; Beeman, J.W.

    1996-09-01

    The authors report on recent advances in the development of Neutron Transmutation Doped (NTD) semiconductor thermistors fabricated from germanium of natural and controlled isotopic composition. The near ideal doping uniformity which can be achieved with the NTD process, the device simplicity of NTD Ge thermistors and the high performance of cooled junction field effect transistor (FET) preamplifiers have led to the widespread acceptance of these thermal sensors in many radiotelescopes operating on the ground, on high altitude aircraft and on spaceborne satellites. These features also have made possible the development of efficient bolometer arrays which are beginning to produce exciting results.

  8. Synthesis of (Zr, Y, Am)O2-x transmutation targets

    NASA Astrophysics Data System (ADS)

    Nästren, C.; Staicu, D.; Somers, J.; Fernandez, A.

    2013-02-01

    A process consisting of sol gel external gelation and infiltration steps has been developed for the synthesis of oxide fuels and targets for the transmutation of minor actinides, in this case americium. Carbon has been introduced into the sol gel produced beads, removal of which leads to higher porosity. In addition, the beads are softer enabling better pressing characteristics and most importantly an optimised microstructure devoid of lenticular pores. This microstructure improvement has a strong positive effect on the thermal conductivity, which is increased by 40%. Thus, the margin between operating temperature and melting temperature of the fuel is increased, improving significantly safety aspects of the fuel in the reactor.

  9. Transuranic Transmutation and Criticality Calculation Sensitivity to Heterogeneous Lattice Effects - 12391

    SciTech Connect

    Barbaras, Sean A.; Knight, Travis W.

    2012-07-01

    Using Mixed Oxide (MOX) fuel in traditional Pressurized Water Reactor (PWR) assemblies has been researched at length and has shown to provide the benefit of transmutation and targets the amount and toxicity of high level waste needed to be managed. Advanced MOX concepts using enriched Uranium Dioxide (UO{sub 2}) are required for multiple recycling of plutonium. The use of MOX and ordinary UO{sub 2} fuel in the same assembly as well as unfueled rods and assembly edge effects contrasts with the unit cell computational assumption of a uniform infinite array of rods. While a deterministic method of calculating the Dancoff factor has traditionally been employed in fuel assembly analysis due to the lighter computational and modeling requirements, this research seeks to determine the validity of the uniform, infinite lattice assumption with respect to Dancoff factor and determine the magnitude of the impact of nonuniform lattice effects on fuel assembly criticality calculations as well as transuranic isotope production and transmutation. This research explored the pin-to-pin interaction in a non-uniform lattice of MOX fuel rods and UO{sub 2} fuel rods through the impact of the calculated Dancoff factors from the deterministic method used in SCALE versus the Monte Carlo method used in the code DANCOFF-MC. Using the Monte Carlo method takes into account the non-uniform lattice effects of having neighboring fuel rods with different cross-sectional spectra whereas the Dancoff factor calculated by SCALE assumes a uniform, infinite lattice of one fuel rod type. Differences in eigenvalue calculations as a function of burnup are present between the two methods of Dancoff factor calculation. The percent difference is greatest at low burnup and then becomes smaller throughout the cycle. Differences in the transmutation rate of transuranic isotopes in the MOX fuel are also present between the Dancoff factor calculation methods. The largest difference is in Pu-239, Pu-242, and Am-241

  10. Transmutation of skyrmions to half-solitons driven by the nonlinear optical spin Hall effect.

    PubMed

    Flayac, H; Solnyshkov, D D; Shelykh, I A; Malpuech, G

    2013-01-01

    We show that the spin domains, generated in the linear optical spin Hall effect by the analog of spin-orbit interaction for exciton polaritons, are associated with the formation of a Skyrmion lattice. In the nonlinear regime, the spin anisotropy of the polariton-polariton interactions results in a spatial compression of the domains and in a transmutation of the Skyrmions into oblique half-solitons. This phase transition is associated with both the focusing of the spin currents and the emergence of a strongly anisotropic emission pattern. PMID:23383815

  11. Optimisation of the neutron source based on gas dynamic trap for transmutation of radioactive wastes

    NASA Astrophysics Data System (ADS)

    Anikeev, Andrey V.

    2012-06-01

    The Budker Institute of Nuclear Physics in collaboration with the Russian and foreign organizations develop the project of 14 MeV neutron source, which can be used for fusion material studies and for other application. The projected neutron source of plasma type is based on the plasma Gas Dynamic Trap (GDT), which is a special magnetic mirror system for plasma confinement. Presented work continues the subject of development the GDT-based neutron source (GDT-NS) for hybrid fusion-fission reactors. The paper presents the results of recent numerical optimization of such neutron source for transmutation of the long-lives radioactive wastes in spent nuclear fuel.

  12. High flux Particle Bed Reactor systems for rapid transmutation of actinides and long lived fission products

    SciTech Connect

    Powell, J.; Ludewig, H.; Maise, G.; Steinberg, M.; Todosow, M.

    1993-08-01

    An initial assessment of several actinide/LLFP burner concepts based on the Particle Bed Reactor (PBR) is described. The high power density/flux level achievable with the PBR make it an attractive candidate for this application. The PBR based actinide burner concept also possesses a number of safety and economic benefits relative to other reactor based transmutation approaches including a low inventory of radionuclides, and high integrity, coated fuel particles which can withstand extremely high in temperatures while retaining virtually all fission products. In addition the reactor also posesses a number of ``engineered safety features,`` which, along with the use of high temperature capable materials further enhance its safety characteristics.

  13. Robert Boyle, Transmutation, and the History of Chemistry before Lavoisier: A Response to Kuhn.

    PubMed

    Newman, William R

    2014-01-01

    In an influential article of 1952, Thomas Kuhn argued that Robert Boyle had little or no influence on the subsequent development of chemistry. This essay challenges Kuhn's view on two fronts. First, it shows that Johann Joachim Becher developed his hierarchical matter theory under the influence of Boyle and then transmitted it to the founder of the phlogiston theory, G. E. Stahl. Second, this essay argues that transmutational matter theories were not necessarily opposed to the existence of stable chemical species, pace Kuhn. Boyle's corpuscular theory descended largely from the tradition of "chymical atomism," which often advocated both chrysopoeia and the reality of robust chemical substances. PMID:26103748

  14. Microstructural Changes In Thermally Cycled U-Pu-Zr-Am-Np Metallic Transmutation Fuel With 1.5% Lanthanides

    SciTech Connect

    Dawn E. Janney; J. Rory Kennedy

    2008-06-01

    The United States Department of Energy (DOE) Global Nuclear Energy Partnership (GNEP) is developing metallic actinide-zirconium alloy fuels for the transmutation of minor actinides as part of a closed fuel cycle. The molten salt electrochemical process to be used for fuel recycle has the potential to carry over up to 2% fission product lanthanide content into the fuel fabrication process. Within the scope of the fuel irradiation testing program at Idaho National Laboratory (INL), candidate metal alloy transmutation fuels containing quantities of lanthanide elements have been fabricated, characterized, and delivered to the Advanced Test Reactor for irradiation testing.

  15. Important requirements for RF generators for Accelerator-Driven Transmutation Technologies (ADTT)

    SciTech Connect

    Lynch, M.T.; Tallerico, P.J.; Lawrence, G.P.

    1994-09-01

    All Accelerator-Driven Transmutation applications require very large amounts of RF Power. For example, one version of a Plutonium burning system requires an 800-MeV, 80-mA, proton accelerator running at 100% duty factor. This accelerator requires approximately 110-MW of continuous RF power if one assumes only 10% reserve power for control of the accelerator fields. In fact, to minimize beam spill, the RF controls may need as much as 15 to 20% of reserve power. In addition, unlike an electron accelerator in which the beam is relativistic, a failed RF station can disturb the synchronism of the beam, possibly shutting down the entire accelerator. These issues and more lead to a set of requirements for the RF generators which are stringent, and in some cases, conflicting. In this paper, we will describe the issues and requirements, and outline a plan for RF generator development to meet the needs of the Accelerator-Driven Transmutation Technologies. The key issues which will be discussed include: operating efficiency, operating linearity, effect on the input power grid, bandwidth, gain, reliability, operating voltage, and operating current.

  16. Fusion transmutation of waste: design and analysis of the in-zinerator concept.

    SciTech Connect

    Durbin, S. M.; Cipiti, Benjamin B.; Olson, Craig Lee; Guild-Bingham, Avery (Texas A&M University, College Station, TX); Venneri, Francesco (General Atomics, San Diego, CA); Meier, Wayne; Alajo, A.B.; Johnson, T. R.; El-Guebaly, L. A.; Youssef, M. E.; Young, Michael F.; Drennen, Thomas E. (Hobart & William Smith College, Geneva, NY); Tsvetkov, Pavel Valeryevich (Texas A&M University, College Station, TX); Morrow, Charles W.; Turgeon, Matthew C.; Wilson, Paul (University of Wisconsin, Madison, WI); Phruksarojanakun, Phiphat (University of Wisconsin, Madison, WI); Grady, Ryan (University of Wisconsin, Madison, WI); Keith, Rodney L.; Smith, James Dean; Cook, Jason T.; Sviatoslavsky, Igor N. (University of Wisconsin, Madison, WI); Willit, J. L. (Argonne Mational Laboratory, Argonne, IL); Cleary, Virginia D.; Kamery, William; Mehlhorn, Thomas Alan; Rochau, Gary Eugene

    2006-11-01

    Due to increasing concerns over the buildup of long-lived transuranic isotopes in spent nuclear fuel waste, attention has been given in recent years to technologies that can burn up these species. The separation and transmutation of transuranics is part of a solution to decreasing the volume and heat load of nuclear waste significantly to increase the repository capacity. A fusion neutron source can be used for transmutation as an alternative to fast reactor systems. Sandia National Laboratories is investigating the use of a Z-Pinch fusion driver for this application. This report summarizes the initial design and engineering issues of this ''In-Zinerator'' concept. Relatively modest fusion requirements on the order of 20 MW can be used to drive a sub-critical, actinide-bearing, fluid blanket. The fluid fuel eliminates the need for expensive fuel fabrication and allows for continuous refueling and removal of fission products. This reactor has the capability of burning up 1,280 kg of actinides per year while at the same time producing 3,000 MWth. The report discusses the baseline design, engineering issues, modeling results, safety issues, and fuel cycle impact.

  17. Georgia Institute of Technology research on the Gas Core Actinide Transmutation Reactor (GCATR)

    NASA Technical Reports Server (NTRS)

    Clement, J. D.; Rust, J. H.; Schneider, A.; Hohl, F.

    1976-01-01

    The program reviewed is a study of the feasibility, design, and optimization of the GCATR. The program is designed to take advantage of initial results and to continue work carried out on the Gas Core Breeder Reactor. The program complements NASA's program of developing UF6 fueled cavity reactors for power, nuclear pumped lasers, and other advanced technology applications. The program comprises: (1) General Studies--Parametric survey calculations performed to examine the effects of reactor spectrum and flux level on the actinide transmutation for GCATR conditions. The sensitivity of the results to neutron cross sections are to be assessed. Specifically, the parametric calculations of the actinide transmutation are to include the mass, isotope composition, fission and capture rates, reactivity effects, and neutron activity of recycled actinides. (2) GCATR Design Studies--This task is a major thrust of the proposed research program. Several subtasks are considered: optimization criteria studies of the blanket and fuel reprocessing, the actinide insertion and recirculation system, and the system integration. A brief review of the background of the GCATR and ongoing research is presented.

  18. Accelerator-driven transmutation of high-level waste from the defense and commercial sectors

    SciTech Connect

    Bowman, C.; Arthur, E.; Beard, C.

    1996-09-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The major goal has been to develop accelerator transmutation of waste (ATW) system designs that will thoroughly and rapidly transmute nuclear waste, including plutonium from dismantled weapons and spent reactor fuel, while generating useful electrical power and without producing a long-lived radioactive waste stream. We have identified and quantified the unique qualities of subcritical nuclear systems and their capabilities in bringing about the complete destruction of plutonium. Although the 1191 subcritical systems involved in our most effective designs radically depart from traditional nuclear reactor concepts, they are based on extrapolations of existing technologies. Overall, care was taken to retain the highly desired features that nuclear technology has developed over the years within a conservative design envelope. We believe that the ATW systems designed in this project will enable almost complete destruction of nuclear waste (conversion to stable species) at a faster rate and without many of the safety concerns associated with the possible reactor approaches.

  19. Transmutation and activation analysis for divertor materials in a HCLL-type fusion power reactor

    NASA Astrophysics Data System (ADS)

    Fischer, U.; Pereslavtsev, P.; Möslang, A.; Rieth, M.

    2009-04-01

    The activation and transmutation of tungsten and tantalum as plasma facing materials was assessed for a helium cooled divertor irradiated in a typical fusion power reactor based on the use of Helium-cooled Lithium Lead (HCLL) blankets. 3D activation calculations were performed by applying a programme system linking the Monte Carlo transport code MCNP and the fusion inventory code FISPACT through an appropriate interface. Special attention was given to the proper treatment of the resonance shielding of tungsten and tantalum by using reaction rates provided directly by MCNP on the basis of continuous energy activation cross-section data. It was shown that the long-term activation behaviour is dominated by activation products of the assumed tramp material while the short-term behaviour is due to the activation of the stable Ta and W isotopes. The recycling limit for remote handling of 100 mSv/h can be achieved after decay times of 10 and 50 years for Ta and W, respectively. The elemental transmutation rates of Ta and W were shown to be on a moderate level for the HCLL-type fusion power reactor.

  20. Neutron-transmuted carbon-14 in neutron-irradiated GaN: Compensation of DX-like center

    SciTech Connect

    Ida, T.; Oga, T.; Kuriyama, K.; Kushida, K.; Xu, Q.; Fukutani, S.

    2013-12-04

    The transmuted-C related luminescence and net carrier concentration are studied by combining photoluminescence, liquid scintillation, and Raman scattering. GaN single crystal films grown by metalorganic-vapor-phase epitaxy are irradiated with fast and thermal neutrons at fluxes of 3.9 × 10{sup 13} cm{sup −2}s{sup −1} and 8.15 × 10{sup 13} cm{sup −2}s{sup −1}, respectively. Irradiation time is 48 hours. The calculated {sup 72}Ge and {sup 14}C concentrations are 1.24 × 10{sup 18} cm{sup −3} and 1.13 × 10{sup 18} cm{sup −3}, respectively. The transmuted {sup 14}C is detected by the liquid scintillation method to survey β-rays emitted in the process of {sup 14}C decays from {sup 14}N. Tritium ({sup 3}H) is also emitted by a (n,t) reaction of {sup 14}N due to the neutron irradiation above 4.5 MeV. Photoluminescence relating to C, DX-like center of Ge and yellow luminescence band are observed in 1000 °C annealed NTD-GaN. The free electron concentration estimated from Raman scattering is 4.97 × 10{sup 17} cm{sup −3}. This value is lower than that from the transmuted Ge concentration, suggesting the compensation due to the transmuted {sup 14}C acceptors.

  1. Preliminary neutronics design of china lead-alloy cooled demonstration reactor (CLEAR-III) for nuclear waste transmutation

    SciTech Connect

    Chen, Z.; Chen, Y.; Bai, Y.; Wang, W.; Chen, Z.; Hu, L.; Long, P.

    2012-07-01

    China Lead-Alloy cooled Demonstration Reactor (CLEAR-III), which is the concept of lead-bismuth cooled accelerator driven sub-critical reactor for nuclear waste transmutation, was proposed and designed by FDS team in China. In this study, preliminary neutronics design studies have primarily focused on three important performance parameters including Transmutation Support Ratio (TSR), effective multiplication factor and blanket thermal power. The constraint parameters, such as power peaking factor and initial TRU loading, were also considered. In the specific design, uranium-free metallic dispersion fuel of (TRU-Zr)-Zr was used as one of the CLEAR-III fuel types and the ratio between MA and Pu was adjusted to maximize transmutation ratio. In addition, three different fuel zones differing in the TRU fraction of the fuel were respectively employed for this subcritical reactor, and the zone sizes and TRU fractions were determined such that the linear powers of these zones were close to each other. The neutronics calculations and analyses were performed by using Multi-Functional 4D Neutronics Simulation System named VisualBUS and nuclear data library HENDL (Hybrid Evaluated Nuclear Data Library). In the preliminary design, the maximum TSRLLMA was {approx}11 and the blanket thermal power was {approx}1000 MW when the effective multiplication factor was 0.98. The results showed that good performance of transmutation could be achieved based on the subcritical reactor loaded with uranium-free fuel. (authors)

  2. Transmutation of All German Transuranium under Nuclear Phase Out Conditions – Is This Feasible from Neutronic Point of View?

    PubMed Central

    Merk, Bruno; Litskevich, Dzianis

    2015-01-01

    The German government has decided for the nuclear phase out, but a decision on a strategy for the management of the highly radioactive waste is not defined yet. Partitioning and Transmutation (P&T) could be considered as a technological option for the management of highly radioactive waste, therefore a wide study has been conducted. In the study group objectives for P&T and the boundary conditions of the phase out have been discussed. The fulfillment of the given objectives is analyzed from neutronics point of view using simulations of a molten salt reactor with fast neutron spectrum. It is shown that the efficient transmutation of all existing transuranium isotopes would be possible from neutronic point of view in a time frame of about 60 years. For this task three reactors of a mostly new technology would have to be developed and a twofold life cycle consisting of a transmuter operation and a deep burn phase would be required. A basic insight for the optimization of the time duration of the deep burn phase is given. Further on, a detailed balance of different isotopic inventories is given to allow a deeper understanding of the processes during transmutation in the molten salt fast reactor. The effect of modeling and simulation is investigated based on three different modeling strategies and two different code versions. PMID:26717509

  3. Design and parameter optimization of a small-scale electron-based ADS for radioactive waste transmutation

    NASA Astrophysics Data System (ADS)

    Feizi, H.; Ranjbar, A. H.

    2015-05-01

    This paper presents the design and feasibility of an electron-LINAC-based small-scale system (ADS) for nuclear waste transmutation. FLUKA simulations have been performed to evaluate the photoneutron yield in high- Z metallic targets such as silver, tungsten, lead, tantalum and uranium irradiated by electron beams of 20-200MeV. The parameters involved in the photoneutron production mechanism including electron beam energy, target material and target shape have been investigated in order to obtain maximum photoneutron production. The neutron reflectors of the ADS, in particular, beryllium, lead and beryllium oxide (BeO) with various thicknesses have been studied. The results show that a combination of an internal reflector of Pb with a thickness of 3cm and an external reflector of BeO with a thickness of 10cm improves the fluence rate. The photoneutron energy spectrum, photoneutron fluence distribution and heat deposition in the electron target have also been presented. At incident electron beam energy of 155MeV, a neutron source of ˜ 4.6 × 1010 (n/cm2/s/mA) has been achieved, which is highly applicable for using in nuclear waste transmutation. The designed ADS has the ability to transmute ˜ 1.5 × 1022 (atoms/y/mA). The obtained results are promising and could lead to the development of a small-scale ADS based on electron LINAC for radioactive waste transmutation and for numerous applications when employed as a photoneutron source.

  4. Transmutation of All German Transuranium under Nuclear Phase Out Conditions - Is This Feasible from Neutronic Point of View?

    PubMed

    Merk, Bruno; Litskevich, Dzianis

    2015-01-01

    The German government has decided for the nuclear phase out, but a decision on a strategy for the management of the highly radioactive waste is not defined yet. Partitioning and Transmutation (P&T) could be considered as a technological option for the management of highly radioactive waste, therefore a wide study has been conducted. In the study group objectives for P&T and the boundary conditions of the phase out have been discussed. The fulfillment of the given objectives is analyzed from neutronics point of view using simulations of a molten salt reactor with fast neutron spectrum. It is shown that the efficient transmutation of all existing transuranium isotopes would be possible from neutronic point of view in a time frame of about 60 years. For this task three reactors of a mostly new technology would have to be developed and a twofold life cycle consisting of a transmuter operation and a deep burn phase would be required. A basic insight for the optimization of the time duration of the deep burn phase is given. Further on, a detailed balance of different isotopic inventories is given to allow a deeper understanding of the processes during transmutation in the molten salt fast reactor. The effect of modeling and simulation is investigated based on three different modeling strategies and two different code versions. PMID:26717509

  5. AFCI Transmutation Fuel Processes and By-Products Planning: Interim Report

    SciTech Connect

    Eric L. Shaber

    2005-09-01

    The goals of the Advanced Fuel Cycle Initiative (AFCI) Program are to reduce high-level waste volume, reduce long-lived and radiotoxic elements, and reclaim valuable energy content of spent nuclear fuel. The AFCI chartered the Fuel Development Working Group (FDWG) to develop advanced fuels in support of the AFCI goals. The FDWG organized a phased strategy of fuel development that is designed to match the needs of the AFCI program: Phase 1 - High-burnup fuels for light-water reactors (LWRs) and tri-isotopic (TRISO) fuel for gas-cooled reactors Phase 2 – Mixed oxide fuels with minor actinides for LWRs, Am transmutation targets for LWRs, inert matrix fuels for LWRs, and TRISO fuel containing Pu and other transuranium for gas-cooled reactors Phase 3 – Fertile free or low-fertile metal, ceramic, ceramic dispersed in a metal matrix (CERMET), and ceramics dispersed in a ceramic matrix (CERCER) that would be used primarily in fast reactors. Development of advanced fuels requires the fabrication, assembly, and irradiation of prototypic fuel under bounding reactor conditions. At specialized national laboratory facilities small quantities of actinides are being fabricated into such fuel for irradiation tests. Fabrication of demonstration quantities of selected fuels for qualification testing is needed but not currently feasible, because existing manual glovebox fabrication approaches result in significant radiation exposures when larger quantities of actinides are involved. The earliest demonstration test fuels needed in the AFCI program are expected to be variants of commercial mixed oxide fuel for use in an LWR as lead test assemblies. Manufacture of such test assemblies will require isolated fabrication lines at a facility not currently available in the U.S. Such facilities are now being planned as part of an Advanced Fuel Cycle Facility (AFCF). Adequate planning for and specification of actinide fuel fabrication facilities capable of producing transmutation fuels

  6. Effects of solid transmutants and helium in copper studied by mixed-spectrum neutron irradiation

    NASA Astrophysics Data System (ADS)

    Muroga, T.; Watanabe, H.; Yoshida, N.

    1998-10-01

    Microstructures of pure Cu and Cu-Ni-Zn alloys irradiated in High Flux Isotope Reactor (HFIR) at 573 K to 9.2 dpa and 673 K to 10.4 dpa have been observed with TEM. Transmutant Ni and Zn of ˜3 wt% were produced during the irradiation. The effect of Ni and Zn production during irradiation was interpreted based on the knowledge obtained from Fast Flux Test Facility (FFTF) irradiated Cu and Cu-Ni-Zn alloys. The effect of He produced from Ni in Cu-5Ni during irradiation in HFIR was consistent with that produced from 10B in Cu-5Ni- 10B during irradiation in FFTF.

  7. Transmutation of Personal Glucose Meters into Portable and Highly Sensitive Microbial Pathogen Detection Platform.

    PubMed

    Wang, Zhenzhen; Chen, Zhaowei; Gao, Nan; Ren, Jinsong; Qu, Xiaogang

    2015-10-01

    Herein, for the first time, we presented a simple and general approach by using personal glucose meters (PGM) for portable and ultrasensitive detection of microbial pathogens. Upon addition of pathogenic bacteria, glucoamylase-quaternized magnetic nanoparticles (GA-QMNPS) conjugates were disrupted by the competitive multivalent interactions between bacteria and QMNPS, resulting in the release of GA. After magnetic separation, the free GA could catalyze the hydrolysis of amylose into glucose for quantitative readout by PGM. In such way, PGM was transmuted into a bacterial detection device and extremely low detection limits down to 20 cells mL(-1) was achieved. More importantly, QMNPS could inhibit the growth of the bacteria and destroy its cellular structure, which enabled bacteria detection and inhibition simultaneously. The simplicity, portability, sensitivity and low cost of presented work make it attractive for clinical applications. PMID:26153225

  8. Laser-Bioplasma Interaction: The Blood Type Transmutation Induced by Multiple Ultrashort Wavelength Laser Beams

    NASA Astrophysics Data System (ADS)

    Stefan, V. Alexander

    2015-11-01

    The interaction of ultrashort wavelength multi laser beams with the flowing blood thin films leads to the transmutation of the blood types A, B, and AB into O type. This is a novel mechanism of importance for the transfusion medicine. Laser radiation is in resonance with the eigen-frequency modes of the antigen proteins and forces the proteins to parametrically oscillate until they get kicked out from the surface. The stripping away of antigens is done by the scanning-multiple-lasers of a high repetition rate in the blue-purple frequency domain. The guiding-lasers are in the red-green frequency domain. The laser force, (parametric interaction with the antigen eigen-oscillation), upon the antigen protein molecule must exceed its weight. The scanning laser beam is partially reflected as long as the antigen(s) is not eliminated. The process of the protein detachment can last a few minutes. Supported by Nikola Tesla Labs., Stefan University.

  9. Actinide partitioning-transmutation program final report. IV. Miscellaneous aspects. [Transport; fuel fabrication; decay; policy; economics

    SciTech Connect

    Alexander, C.W.; Croff, A.G.

    1980-09-01

    This report discusses seven aspects of actinide partitioning-transmutation (P-T) which are important in any complete evaluation of this waste treatment option but which do not fall within other major topical areas concerning P-T. The so-called miscellaneous aspects considered are (1) the conceptual design of a shipping cask for highly neutron-active fresh and spent P-T fuels, (2) the possible impacts of P-T on mixed-oxide fuel fabrication, (3) alternatives for handling the existing and to-be-produced spent fuel and/or wastes until implementation of P-T, (4) the decay and dose characteristics of P-T and standard reactor fuels, (5) the implications of P-T on currently existing nuclear policy in the United States, (6) the summary costs of P-T, and (7) methods for comparing the risks, costs, and benefits of P-T.

  10. Transmutation of singularities and zeros in graded index optical instruments: a methodology for designing practical devices.

    PubMed

    Hooper, I R; Philbin, T G

    2013-12-30

    We describe a design methodology for modifying the refractive index profile of graded-index optical instruments that incorporate singularities or zeros in their refractive index. The process maintains the device performance whilst resulting in graded profiles that are all-dielectric, do not require materials with unrealistic values, and that are impedance matched to the bounding medium. This is achieved by transmuting the singularities (or zeros) using the formalism of transformation optics, but with an additional boundary condition requiring the gradient of the co-ordinate transformation be continuous. This additional boundary condition ensures that the device is impedance matched to the bounding medium when the spatially varying permittivity and permeability profiles are scaled to realizable values. We demonstrate the method in some detail for an Eaton lens, before describing the profiles for an "invisible disc" and "multipole" lenses. PMID:24514824

  11. Pyrochemical separations technologies envisioned for the U. S. accelerator transmutation of waste system

    SciTech Connect

    Laidler, J. J.

    2000-02-17

    A program has been initiated for the purpose of developing the chemical separations technologies necessary to support a large Accelerator Transmutation of Waste (ATW) system capable of dealing with the projected inventory of spent fuel from the commercial nuclear power stations in the United States. The baseline process selected combines aqueous and pyrochemical processes to enable the efficient separation of uranium, technetium, iodine, and the transuranic elements from LWR spent fuel. The diversity of processing methods was chosen for both technical and economic factors. A six-year technology evaluation and development program is foreseen, by the end of which an informed decision can be made on proceeding with demonstration of the ATW system.

  12. A Heterogeneous Sodium Fast Reactor Designed to Transmute Minor Actinide Actinide Waste Isotopes into Plutonium Fuel

    SciTech Connect

    Samuel E. Bays

    2011-02-01

    An axial heterogeneous sodium fast reactor design is developed for converting minor actinide waste isotopes into plutonium fuel. The reactor design incorporates zirconium hydride moderating rods in an axial blanket above the active core. The blanket design traps the active core’s axial leakage for the purpose of transmuting Am-241 into Pu-238. This Pu-238 is then co-recycled with the spent driver fuel to make new driver fuel. Because Pu-238 is significantly more fissile than Am-241 in a fast neutron spectrum, the fissile worth of the initial minor actinide material is upgraded by its preconditioning via transmutation in the axial targets. Because, the Am-241 neutron capture worth is significantly stronger in a moderated epithermal spectrum than the fast spectrum, the axial targets serve as a neutron trap which recovers the axial leakage lost by the active core. The sodium fast reactor proposed by this work is designed as an overall transuranic burner. Therefore, a low transuranic conversion ratio is achieved by a degree of core flattening which increases axial leakage. Unlike a traditional “pancake” design, neutron leakage is recovered by the axial target/blanket system. This heterogeneous core design is constrained to have sodium void and Doppler reactivity worth similar to that of an equivalent homogeneous design. Because minor actinides are irradiated only once in the axial target region; elemental partitioning is not required. This fact enables the use of metal targets with electrochemical reprocessing. Therefore, the irradiation environment of both drivers and targets was constrained to ensure applicability of the established experience database for metal alloy sodium fast reactor fuels.

  13. Thermal conductivity changes upon neutron transmutation of {sup 10}B doped diamond

    SciTech Connect

    Jagannadham, K.; Verghese, K.; Butler, J. E.

    2014-08-28

    {sup 10}B doped p-type diamond samples were subjected to neutron transmutation reaction using thermal neutron flux of 0.9 × 10{sup 13} cm{sup −2} s{sup −1} and fast neutron flux of 0.09 × 10{sup 13} cm{sup −2} s{sup −1}. Another sample of epilayer grown on type IIa (110) single crystal diamond substrate was subjected to equal thermal and fast neutron flux of 10{sup 14} cm{sup −2} s{sup −1}. The defects in the diamond samples were previously characterized by different methods. In the present work, thermal conductivity of these diamond samples was determined at room temperature by transient thermoreflectance method. The thermal conductivity change in the samples as a function of neutron fluence is explained by the phonon scattering from the point defects and disordered regions. The thermal conductivity of the diamond samples decreased more rapidly initially and less rapidly for larger neutron fluence. In addition, the thermal conductivity in type IIb diamond decreased less rapidly with thermal neutron fluence compared to the decrease in type IIa diamond subjected to fast neutron fluence. It is concluded that the rate of production of defects during transmutation reaction is slower when thermal neutrons are used. The thermal conductivity of epilayer of diamond subjected to high thermal and fast neutron fluence is associated with the covalent carbon network in the composite structure consisting of disordered carbon and sp{sup 2} bonded nanocrystalline regions.

  14. AFC-1 Transmutation Fuels Post-Irradiation Hot Cell Examination 4-8 at.% - Final Report (Irradiation Experiments AFC-1B, -1F and -1Æ)

    SciTech Connect

    Bruce Hilton; Douglas Porter; Steven Hayes

    2006-09-01

    The AFC-1B, AFC-1F and AFC-1Æ irradiation tests are part of a series of test irradiations designed to evaluate the feasibility of the use of actinide bearing fuel forms in advanced fuel cycles for the transmutation of transuranic elements from nuclear waste. The tests were irradiated in the Idaho National Laboratory’s (INL) Advanced Test Reactor (ATR) to an intermediate burnup of 4 to 8 at% (2.7 - 6.8 x 1020 fiss/cm3). The tests contain metallic and nitride fuel forms with non-fertile (i.e., no uranium) and low-fertile (i.e., uranium bearing) compositions. Results of postirradiation hot cell examinations of AFC-1 irradiation tests are reported for eleven metallic alloy transmutation fuel rodlets and five nitride transmutation fuel rodlets. Non-destructive examinations included visual examination, dimensional inspection, gamma scan analysis, and neutron radiography. Detailed examinations, including fission gas puncture and analysis, metallography / ceramography and isotopics and burnup analyses, were performed on five metallic alloy and three nitride transmutation fuels. Fuel performance of both metallic alloy and nitride fuel forms was best correlated with fission density as a burnup metric rather than at.% depletion. The actinide bearing transmutation metallic alloy compositions exhibit irradiation performance very similar to U-xPu-10Zr fuel at equivalent fission densities. The irradiation performance of nitride transmutation fuels was comparable to limited data published on mixed nitride systems.

  15. The Changes of Energy Interactions between Nucleus Function and Mitochondria Functions Causing Transmutation of Chronic Inflammation into Cancer Metabolism.

    PubMed

    Ponizovskiy, Michail R

    2016-01-01

    Interactions between nucleus and mitochondria functions induce the mechanism of maintenance stability of cellular internal energy according to the first law of thermodynamics in able-bodied cells and changes the mechanisms of maintenance stability of cellular internal energy creating a transition stationary state of ablebodied cells into quasi-stationary pathologic states of acute inflammation transiting then into chronic inflammation and then transmuting into cancer metabolism. The mechanisms' influences of intruding etiologic pathologic agents (microbe, virus, etc.) lead to these changes of energy interactions between nucleus and mitochondria functions causing general acute inflammation, then passing into local chronic inflammation, and reversing into cancer metabolism transmutation. Interactions between biochemical processes and biophysical processes of cellular capacitors' operations create a supplementary mechanism of maintenance stability of cellular internal energy in the norm and in pathology. Discussion of some scientific works eliminates doubts of the authors of these works. PMID:27480780

  16. Increasing the Acceptance of Spent Nuclear Fuel Disposal by the Transmutation of Minor Actinides Using an Accelerator

    NASA Astrophysics Data System (ADS)

    Sheffield, Richard L.

    2010-02-01

    The main challenge in nuclear fuel cycle closure is the reduction of the potential radiotoxicity of spent LWR nuclear fuel, or the length of time in which that potential hazard exists. Partitioning and accelerator-based transmutation in combination with geological disposal can lead to an acceptable societal solution for the nuclear spent fuel management problem. Nuclear fuel seems ideally suited for recycling. Only a small fraction of the available energy in the fuel is extracted in a single pass and the problem isotopes, consisting of the transuranic elements plutonium, neptunium, americium, curium and the long-lived fission products iodine and technetium, could be burned in fast-neutron spectrum reactors or sub-critical accelerator driven transmuters. Most of the remaining wastes have half-lives of a few hundred years and can be safely stored in man-made containment structures (casks or glass). The very small amount of remaining long-lived waste could be safely stored in a small geologic repository. The problem for the next 100 years is that a sufficient number of fast reactors are unlikely to be built by industry to burn its own waste and the waste from existing and new light water reactors (LWRs). So an interim solution is required to transition to a fast reactor economy. The goals of accelerator transmutation are some or all of the following: 1) to significantly reduce the impacts due to the minor actinides on the packing density and long-term radiotoxicity in the repository design, 2) preserve/use the energy-rich component of used nuclear fuel, and 3) reduce proliferation risk. Accelerator-based transmutation could lead to a greater percentage of our power coming from greenhouse-gas emission-free nuclear power and provide a long-term strategy enabling the continuation and growth of nuclear power in the U.S. )

  17. Fusion transmutation of waste and the role of the In-Zinerator in the nuclear fuel cycle.

    SciTech Connect

    Cipiti, Benjamin B.

    2006-06-01

    The Z-Pinch fusion experiment at Sandia National Laboratories has been making significant progress in developing a high-energy fusion neutron source. This source has the potential to be used for the transmutation of nuclear waste. The goal of this research was to do a scoping-level design of a fusion-based transmuter to determine potential transmutation rates along with the fusion yield requirements. Two ''In-Zinerator'' designs have been developed to transmute the long-lived actinides that dominate the heat production in spent fuel. The first design burns up all transuranics (TRU) in spent fuel (Np, Pu, Am, Cm), and the second is focused only on burning up Am and Cm. The TRU In-Zinerator is designed for a fuel cycle requiring burners to get rid of all the TRU with no light water reactor (LWR) recycle. The Am/Cm In-Zinerator is designed for a fuel cycle with Np/Pu recycling in LWRs. Both types of In-Zinerators operate with a moderate fusion source driving a sub-critical actinide blanket. The neutron multiplication is 30, so a great deal of energy is produced in the blanket. With the design goal of generating 3,000 MW{sub th}, about 1,200 kg/yr of actinides can be destroyed in each In-Zinerator. Each TRU In-Zinerator will require a 20 MW fusion source, and it will take a total of 20 units (each producing 3,000 MWth) to burn up the TRU as fast as the current LWR fleet can produce it. Each Am/Cm In-Zinerator will require a 24 MW fusion source, and it will take a total of 2 units to burn up the Am/Cm as fast as the current LWR fleet can produce it. The necessary fusion yield could be achieved using a 200-240 MJ target fired once every 10 seconds.

  18. Determination of transmutation effects in crystalline waste forms. 1997 annual progress report

    SciTech Connect

    Strachan, D.M.; Buck, E.C.; Fortner, J.A.; Hess, N.J.

    1997-01-01

    'A team from two national laboratories is studying transmutation effects in crystalline waste forms. Analyses are being done with 18 year old samples of {sup 137}Cs-bearing pollucite (CsAlSi{sub 2}O{sub 6} \\267 0.5 H{sub 2}O) obtained from a French company. These samples are unique in that the pollucite was made with various amounts of {sup 137}Cs, which was then sealed in welded stainless- steel capsules to be used as tumor irradiation sources. Over the past 18 years, the {sup 137}Cs has been decaying to stable Ba in the capsules, i.e., in the absence of atmospheric effects. This material serves as an analogue to a crystalline waste form in which such a transmutation occurs to possibly disrupt the integrity of the original waste form. Work this year consisted of determining the construction of the capsule and state of the pollucite in the absence of details about these components from the French company. The authors have opened one capsule containing nonradioactive pollucite. The information on the construction of the stainless-steel capsule is useful for the work that the authors are preparing to do on capsules containing radioactive pollucite. Microscopic characterization of the nonradioactive pollucite revealed that there are at least two compounds in addition to pollucite: a Cs-silicate and a Cs-aluminosilicate (CsAlSiO{sub 4}). These findings may complicate the interpretation of the planned experiments using X-ray absorption spectroscopy. Electron energy loss spectroscopy and energy dispersive X-ray spectroscopy (flourescence) have been used to characterize the nonradioactive pollucite. They have investigated the stability of the nonradioactive pollucite to {beta} radiation damage by use of 200 keV electrons in a transmission electron microscope. The samples were found to become amorphous in less than 10 minutes with loss of Cs. This is equivalent to many more years of {beta} radiation damage than under normal decay of the {sup 137}Cs. In fact, the dose was

  19. Random Probability Analysis of 48Ca +239Pu Experimental Data

    NASA Astrophysics Data System (ADS)

    Strauss, S. Y.; Henderson, R. A.; Stoyer, M. A.; Abdullin, A. F. Sh.; Brewer, N. T.; Dmitriev, S. N.; Grzywacz, R. K.; Hamilton, J. H.; Itkis, M. G.; Miernik, K.; Oganessian, Yu. Ts.; Polyakov, A. N.; Roberto, J. B.; Rykaczewski, K. P.; Sabelnikov, A. V.; Sagaidak, R. N.; Shirokovsky, I. V.; Shumeyko, M. V.; Subbotin, V. G.; Sukhov, A. M.; Tsyganov, Yu. S.; Utyonkov, V. K.; Voinov, A. A.; Vostokin, G. K.

    2014-09-01

    Element 114 (Fl), was discovered at the Flerov Laboratory of Nuclear Reactions (FLNR) using the 48Ca +244Pu reaction and the Dubna Gas-Filled Recoil Separator (DGFRS). The structural properties of the super heavy elements are still largely unknown. The extent of the region of enhanced stability near Z = 114 and N = 184 is not completely known. To examine these properties, a new experimental data set has been taken using the 48Ca +239Pu reaction at the DGFRS, in an effort to look for lighter isotopes of Fl. Progress on the production of lighter isotopes of Fl, cross-section measurements, and any nuclear decay properties will be discussed. Comparisons with reactions using heavier 242,244Pu targets and Monte Carlo random probability analysis will be highlighted. Element 114 (Fl), was discovered at the Flerov Laboratory of Nuclear Reactions (FLNR) using the 48Ca +244Pu reaction and the Dubna Gas-Filled Recoil Separator (DGFRS). The structural properties of the super heavy elements are still largely unknown. The extent of the region of enhanced stability near Z = 114 and N = 184 is not completely known. To examine these properties, a new experimental data set has been taken using the 48Ca +239Pu reaction at the DGFRS, in an effort to look for lighter isotopes of Fl. Progress on the production of lighter isotopes of Fl, cross-section measurements, and any nuclear decay properties will be discussed. Comparisons with reactions using heavier 242,244Pu targets and Monte Carlo random probability analysis will be highlighted. This work was performed under Contract DE-AC52-07NA27344 and Grant DE-NA0002135.

  20. Neutron transmutation doping of silicon in the SAFARI-1 research reactor

    SciTech Connect

    Louw, P.A.; Robertson, D.G.; Strydom, W.J.

    1994-12-31

    The SAFARI-1 research reactor has operated with an exemplary safety record since commissioning in 1965. As part of a commercialisation effort a silicon irradiation facility (SILIRAD) has been installed in the poolside region of SAFARI-1 for Neutron Transmutation Doping (NTD) of silicon. Commissioning of the facility took place in the last quarter of 1992 with a series of trial irradiations which were performed in close collaboration with Wacker Chemitronic of Germany. A methodology for the determination of irradiation times necessary to achieve the target resistivities was verified on the basis of the results from the trial irradiations. All production activities are controlled by quality assurance procedures. To date some hundred and twelve silicon ingots (103 mm diameter) have been successfully irradiated on a commercial contract basis. The observed axial and radial variations in the resistivity profile of the ingots are very small compared to the profiles associated with conventionally doped silicon and small tolerances on target resistivities are attained. In this paper an overview of the design and characterisation of SILIRAD is given and the methods applied that ensure a quality product are described. Results obtained from trial and production irradiations are presented and the envisaged future modifications to SILIRAD discussed.

  1. Spallation radiation damage and dosimetry for accelerator transmutation of waste applications

    SciTech Connect

    Wechsler, M.S.; Lin, C.; Ferguson, P.D.; Sommer, W.F.

    1993-10-01

    Proposals are currently being made for systems to treat radioactive waste based on the use of accelerator-driven neutron sources. A linear proton accelerator with energies as high as 1600 MeV and currents up to 250 ma are anticipated for the driver. The neutron fluxes may reach up to 10{sup 20} neutrons/m{sup 2}s as generated by the spallation reactions that occur when the protons strike target materials. Calculations are described to determine radiation fluxes and flux spectra inherent in such systems and to estimate likely radiation effects on system components. The calculations use LAHET, a Monte Carlo high-energy transport code, and MCNP, a generalized-geometry, coupled neutron-photon Monte Carlo transport code. Cross sections for displacement and helium production are presented for spallation neutrons of energies from 21 MeV to 1600 MeV for Inconel 718 (Ni plus 18.5, 18.5, 5.1, and 3 wt % of Cr, Fe, Nb, and Mo, respectively), an alloy that is used for the proton beam entry window in several accelerators. In addition, results for this alloy are presented for the primary knocked-on atom (PKA) spectrum and the transmutation yield for 1600 MeV incident neutrons.

  2. Impact of transmutation issues on interpretation of data obtained from fast reactor irradiation experiments

    NASA Astrophysics Data System (ADS)

    Greenwood, L. R.; Garner, F. A.

    2004-08-01

    The subject of fission-fusion correlation is usually cast in terms of reactor-to-reactor differences, but recently the fusion community has become aware of the impact of differences within a given surrogate facility, especially in constant time experiments when different dose levels are attained in different positions of one reactor. For some materials, it is not safe to assume that in-reactor spectral variations are small and of no consequence. This point is illustrated using calculations for fusion-relevant materials that were irradiated in the Fast Flux Test Facility-Materials Open Test Assembly (FFTF-MOTA) over a wide range of in-core and out-of-core positions spanning more than two orders of magnitude in dpa rate. It is shown that although both the neutron spectrum and flux changes, the spectral effectiveness factor, dpa/10 22 n/cm 2 ( E>0.1 MeV), remains remarkably constant over this range. The transmutation rate per dpa varies strongly with reactor position, however.

  3. Impact of Transmutation Issues on Interpretation of Data Obtained From Fast Reactor Irradiation Experiments

    SciTech Connect

    Greenwood, Lawrence R.; Garner, Francis A.

    2004-04-15

    The subject of fission-fusion correlation is usually cast in terms of reactor-to-reactor differences, but recently the fusion community has become aware of the impact of differences within a given surrogate facility, especially in constant time experiments when different dose levels are attained in different positions of one reactor. For some materials, it is not safe to assume that in-reactor spectral variations are small and of no consequence. This point is illustrated using calculations for fusion-relevant materials that were irradiated in the Fast Flux Test Facility – Materials Open Test Assembly (FFTF-MOTA) over a wide range of in-core and out of core positions spanning more than two orders of magnitude in dpa rate. It is shown that although both the neutron spectrum and flux changes, the spectral effectiveness factor, dpa/10(22) superscript n/cm(2) superscript (E > 0.1 MeV), remains remarkably constant over this range. The transmutation rate per dpa varies strongly with reactor position, however.

  4. Multi-Reactor Transmutation Analysis Utility (MRTAU,alpha1): Verification

    SciTech Connect

    Andrea Alfonsi; Samuel E. Bays; Cristian Rabiti; Steven J. Piet

    2011-02-01

    Multi-Reactor Transmutation Utility (MRTAU) is a general depletion/decay algorithm under development at INL to support quick assessment of off-normal fuel cycle scenarios of similar nature to well studied reactor and fuel cycle concepts for which isotopic and cross-section data exists. MRTAU has been used in the past for scoping calculations to determine actinide composition evolution over the course of multiple recycles in Light Water Reactor Mixed Oxide and Sodium cooled Fast Reactor. In these applications, various actinide partitioning scenarios of interest were considered. The code has recently been expanded to include fission product generation, depletion and isotopic evolution over multiple recycles. The capability was added to investigate potential partial separations and/or limited recycling technologies such as Melt-Refining, AIROX, DUPIC or other fuel recycle technology where the recycled fuel stream is not completely decontaminated of fission products prior to being re-irradiated in a subsequent reactor pass. This report documents the code's solution methodology and algorithm as well as its solution accuracy compared to the SCALE6.0 software suite.

  5. Transmutations of supersymmetry through soliton scattering and self-consistent condensates

    NASA Astrophysics Data System (ADS)

    Arancibia, Adrián; Plyushchay, Mikhail S.

    2014-07-01

    We consider the two most general families of the (1+1)D Dirac systems with transparent scalar potentials and two related families of the paired reflectionless Schrödinger operators. The ordinary N=2 supersymmetry for such Schrödinger pairs is enlarged up to an exotic N=4 nonlinear centrally extended supersymmetric structure, which involves two bosonic integrals composed from the Lax-Novikov operators for the stationary Korteweg-de Vries hierarchy. Each associated single Dirac system displays a proper N=2 nonlinear supersymmetry with a nonstandard grading operator. One of the two families of the first- and second-order systems exhibits the unbroken supersymmetry, while another is described by the broken exotic supersymmetry. The two families are shown to be mutually transmuted by applying a certain limit procedure to the soliton scattering data. We relate the topologically trivial and nontrivial transparent potentials with self-consistent inhomogeneous condensates in the Bogoliubov-de Gennes and Gross-Neveu models and indicate the exotic N=4 nonlinear supersymmetry of the paired reflectionless Dirac systems.

  6. Modulated electromagnetic fields in inhomogeneous media, hyperbolic pseudoanalytic functions, and transmutations

    NASA Astrophysics Data System (ADS)

    Khmelnytskaya, Kira V.; Kravchenko, Vladislav V.; Torba, Sergii M.

    2016-05-01

    The time-dependent Maxwell system describing electromagnetic wave propagation in inhomogeneous isotropic media in the one-dimensional case reduces to a Vekua-type equation for bicomplex-valued functions of a hyperbolic variable, see Kravchenko and Ramirez [Adv. Appl. Cliord Algebr. 21(3), 547-559 (2011)]. Using this relation, we solve the problem of the transmission through an inhomogeneous layer of a normally incident electromagnetic time-dependent plane wave. The solution is written in terms of a pair of Darboux-associated transmutation operators [Kravchenko, V. V. and Torba, S. M., J. Phys. A: Math. Theor. 45, 075201 (2012)], and combined with the recent results on their construction [Kravchenko, V. V. and Torba, S. M., Complex Anal. Oper. Theory 9, 379-429 (2015); Kravchenko, V. V. and Torba, S. M., J. Comput. Appl. Math. 275, 1-26 (2015)] can be used for efficient computation of the transmitted modulated signals. We develop the corresponding numerical method and illustrate its performance with examples.

  7. Separation of Transmutation - and Fission-Produced Radioisotopes from Irradiated Beryllium

    SciTech Connect

    Troy J. Tranter; RIchard D. Tillotson; Nick R. Mann; Glen R. Longhurst

    2011-11-01

    The primary objective of this study was to test the effectiveness of a two-step solvent extraction-precipitation process for separating transmutation and fission products from irradiated beryllium. Beryllium metal was dissolved in nitric and fluoroboric acids. Isotopes of 241Am, 239Pu, 85Sr, 60Co, and 137Cs were then added to make a surrogate beryllium waste solution. A series of batch contacts was performed with the spiked simulant using chlorinated cobalt dicarbollide and polyethylene glycol diluted with sulfone to extract the isotopes of Cs and Sr. Another series of batch contacts was performed using a combination of octyl (phenyl)-N,Ndiisobutylcarbamoylmethylphosphine oxide in tributyl phosphate diluted with dodecane for extracting the isotopes of Pu and Am. The 60Co was separated by first forming a cobalt complex and then selectively precipitating the beryllium as a hydroxide. The results indicate that greater than 99.9% removal can be achieved for each radionuclide. Transuranic isotope contamination levels are reduced to less than 100 nCi/g, and sources of high beta-gamma radiation (60Co, 137Cs, and 90Sr) are reduced to levels that will allow the beryllium to be contact handled. The separation process may be applicable to a recycle or waste disposition scenario.

  8. Plasmon transmutation: inducing new modes in nanoclusters by adding dielectric nanoparticles.

    PubMed

    Wen, Fangfang; Ye, Jian; Liu, Na; Van Dorpe, Pol; Nordlander, Peter; Halas, Naomi J

    2012-09-12

    Planar clusters of coupled plasmonic nanoparticles support nanoscale electromagnetic "hot spots" and coherent effects, such as Fano resonances, with unique near and far field signatures, currently of prime interest for sensing applications. Here we show that plasmonic cluster properties can be substantially modified by the addition of individual, discrete dielectric nanoparticles at specific locations on the cluster, introducing new plasmon modes, or transmuting existing plasmon modes to new ones, in the resulting metallodielectric nanocomplex. Depositing a single carbon nanoparticle in the junction between a pair of adjacent nanodisks induces a metal-dielectric-metal quadrupolar plasmon mode. In a ten-membered cluster, placement of several carbon nanoparticles in junctions between multiple adjacent nanoparticles introduces a collective magnetic plasmon mode into the Fano dip, giving rise to an additional subradiant mode in the metallodielectric nanocluster response. These examples illustrate that adding dielectric nanoparticles to metallic nanoclusters expands the number and types of plasmon modes supported by these new mixed-media nanoscale assemblies. PMID:22924627

  9. High power linear accelerators for tritium production and transmutation of nuclear waste

    SciTech Connect

    Lawrence, G.P.

    1990-01-01

    Proton linacs driving high-flux spallation neutron sources are being considered for transmutation of nuclear waste and production of tritium. Advances in high-current linac technology have provided a basis for the development of credible designs for the required accelerator, which has a nominal 1.6-GeV energy, and a 250-mA cw current. A beam with these parameters incident on a liquid lead-bismuth (Pb-Bi) target can generate a thermal neutron flux of up to 5 {times} 10{sup 16} n/cm{sup 2}-s in a cylindrical blanket surrounding the spallation source. This high flux can produce tritium through the {sup 6}Li(n,{alpha})T or {sup 3}He(n,{gamma})T reactions, or can burn long-lived actinides and fission products from nuclear waste through capture and fission processes. In some system scenarios, waste actinides and/or other fissile materials in the blanket can produce sufficient fission energy to power the accelerator.

  10. Determining the americium transmutation rate and fission rate by post-irradiation examination within the scope of the ECRIX-H experiment

    NASA Astrophysics Data System (ADS)

    Lamontagne, J.; Pontillon, Y.; Esbelin, E.; Béjaoui, S.; Pasquet, B.; Bourdot, P.; Bonnerot, J. M.

    2013-09-01

    around 950-960 °C. A second sudden release centred around 1200-1210 °C of greater magnitude and ending around 1340-1350 °C. A last sudden release starting at the base of the second release, centred around 1830 °C and involving most of the released gas. Two small shoulders can be detected at around 1530 °C and 1670 °C. No considerable releases were detected at the end of the 2000 °C plateau and during the ramp up to 2200 °C. That indicates that the total release was reached. Fig. 9 shows the He release (raw data) superimposed on those of 85Kr. This figure shows that the curves are perfectly synchronous (excepting measurement uncertainties). The Am transmutation rate reached was high, ranging between 93.7% and 95.5% depending on the experimental techniques. These results revealed the good correspondence between the transmutation rate measured experimentally by various analytical techniques and that predicted by calculation codes (92.6%). These measurements therefore prove the success of the ECRIX-H experiment. The MgO matrix demonstrated very satisfactory behaviour not only during the basic irradiation which confirmed the first set of PIE [27], but also during a thermal transient. These examinations once again illustrate that magnesia is a good option for the transmutation of minor actinides in pellets with inert matrices. In the future, these new experimental results will be used to optimise the calculation codes that predicted fission rates which were significantly higher than those determined by several experimental techniques. French acronym for Fission Gas Release Study Facility by Annealing.

  11. The ability to create NTD silicon technology in the IRT-T reactor in a horizontal experimental channel with one-side access

    NASA Astrophysics Data System (ADS)

    Varlachev, V. A.; Golovatsky, A. V.; Emets, E. G.; Butko, Ya A.

    2016-06-01

    The article shows the ability of creation of neutron transmutation doping (NTD) of monocrystalline silicon technology in the reactor's channel, which has a one-side access. In the article a distribution of thermal neutron flux through the length of channel and it's radius, neutron spectrum were obtained which confirmed that horizontal experimental channel HEC-1 is suitable for NTD.

  12. Radioactive waste partitioning and transmutation within advanced fuel cycles: Achievements and Challenges

    SciTech Connect

    M. Salvatores; G. Palmiotti

    2011-01-01

    In the last decades, numerous studies have been performed in order to identify appropriate “Partitioning and Transmutation” (P&T) strategies, aiming to the reduction of the burden on a geological storage (see, among many others, Salvatores, 2005). P&T strategies are very powerful and unique tools to reduce drastically the radiotoxicity level of the wastes and to reduce the time needed to reach the reference level (from ~100,000 years to few hundred years, i.e. comparable to the period in which technological and engineering means allow reasonably to control the radioactivity confinement). Moreover, P&T allows, in principle, also the reduction of the residual heat in a geological repository, with a potential significant impact on the repository size and characteristics. The first requirement of P&T strategies is the deployment of spent fuel reprocessing techniques (aqueous or dry), which are both in the continuity of today technologies (e.g. as implemented at La Hague in France, where Pu is separated up to 99.9 %) or which represent innovative, adapted approaches (e.g. pyrochemistry). The requirement is to extend the performance of Pu separation to 99.9 % also to Np, Am and Cm kept together or separated and in any case decontaminated from the lanthanides as much as possible. The separated TRU should then be “transmuted” (or “burned”) in a neutron field. The essential mechanism is to fission them, transforming them into much shorter lived or stable fission products. However, the fission process is always in competition with other processes, and, in particular, with neutron capture, which does eliminate isotope A, but transforms it into isotope A+1, which can still be radioactive. Isotope A+1 can in turn be fissioned or transmuted into isotope A+2, and so on. The neutron field has to be provided by a fission reactor. The requirement for this (dedicated) reactor is to be able to privilege the fission process with respect to the capture process and to be able

  13. Basis and objectives of the Los Alamos Accelerator-Driven Transmutation technology project

    NASA Astrophysics Data System (ADS)

    Bowman, Charles D.

    1995-09-01

    The Accelerator-Driven Transmutation Technology (ADTT) Project carries three approaches for dealing with waste from the defense and commercial nuclear energy enterprise. First, the problem of excess weapons plutonium in the U.S. and Russia originating both from stockpile reductions and from defense production site clean-up is one of significant current and long-term concern. The ADTT technology offers the possibility of almost complete destruction of this plutonium by fission. The technology might be particularly effective for destruction of the low quality plutonium from defense site clean-up since the system does not require the fabrication of the waste into fuel assemblies, does not require reprocessing and refabrication, and can tolerate a high level of impurities in the feed stream. Second, the ADTT system also can destroy the plutonium, other higher actinide, and long-lived fission product from commercial nuclear waste which now can only be dealt with by geologic storage. And finally, and probably most importantly the system can be used for the production of virtually unlimited electric power from thorium with concurrent destruction of its long-lived waste components so that geologic containment for them is not required. In addition plutonium is not a significant byproduct of the power generation so that non-proliferation concerns about nuclear power are almost completely eliminated. All of the ADTT systems operate with an accelerator supplementing the neutrons which in reactors are provided only by the fission process, and therefore the system can be designed to eliminate the possibility for a runaway chain reaction. The means for integration of the accelerator into nuclear power technology in order to make these benefits possible is described including estimates of accelerator operating parameters required for the three objectives.

  14. A Study of Fast Reactor Fuel Transmutation in a Candidate Dispersion Fuel Design

    SciTech Connect

    Mark DeHart; Hongbin Zhang; Eric Shaber; Matthew Jesse

    2010-11-01

    Dispersion fuels represent a significant departure from typical ceramic fuels to address swelling and radiation damage in high burnup fuel. Such fuels use a manufacturing process in which fuel particles are encapsulated within a non-fuel matrix. Dispersion fuels have been studied since 1997 as part of an international effort to develop and test very high density fuel types for the Reduced Enrichment for Research and Test Reactors (RERTR) program.[1] The Idaho National Laboratory is performing research in the development of an innovative dispersion fuel concept that will meet the challenges of transuranic (TRU) transmutation by providing an integral fission gas plenum within the fuel itself, to eliminate the swelling that accompanies the irradiation of TRU. In this process, a metal TRU vector produced in a separations process is atomized into solid microspheres. The dispersion fuel process overcoats the microspheres with a mixture of resin and hollow carbon microspheres to create a TRUC. The foam may then be heated and mixed with a metal power (e.g., Zr, Ti, or Si) and resin to form a matrix metal carbide, that may be compacted and extruded into fuel elements. In this paper, we perform reactor physics calculations for a core loaded with the conceptual fuel design. We will assume a “typical” TRU vector and a reference matrix density. We will employ a fuel and core design based on the Advanced Burner Test Reactor (ABTR) design.[2] Using the CSAS6 and TRITON modules of the SCALE system [3] for preliminary scoping studies, we will demonstrate the feasibility of reactor operations. This paper will describe the results of these analyses.

  15. Use of Thorium for Transmutation of Plutonium and Minor Actinides in PWRs

    SciTech Connect

    Shwageraus, Eugene; Hejzlar, Pavel; Kazimi, Mujid S.

    2004-07-15

    An assessment is made of the potential for Th-based fuel to minimize Pu and minor actinide (MA) production in pressurized water reactors (PWRs). Destruction rates and residual amounts of Pu and MA in the fuel used for transmutation are examined. In particular, sensitivity of these two parameters to the fuel lattice hydrogen to heavy metal (H/HM) ratio and to the fuel composition was systematically investigated. All burnup calculations were performed using CASMO4, the fuel assembly burnup code. The results indicate that up to 1000 kg of reactor-grade Pu can be burned in Th-based fuel assemblies per gigawatt (electric) year. Up to 75% of initial Pu can be destroyed per passage through reactor core. Addition of MA to the fuel mixture degrades the burning efficiency. The theoretically achievable limit for total transuranium (TRU) destruction per passage through the core is 50%. Efficient MA and Pu destruction in Th-based fuel generally requires a higher degree of neutron moderation and, therefore, higher fuel lattice H/HM ratio than typically used in the current generation of PWRs. Reactivity coefficients evaluation demonstrated the feasibility of designing a Th-Pu-MA fueled core with negative Doppler and moderator temperature coefficients. Introduction of TRU-containing fuels to a PWR core inevitably leads to lower control material worths and smaller delayed-neutron yields than with conventional UO{sub 2} cores. Therefore, a major challenge associated with the introduction of Th-TRU fuels to PWRs will be the design of the whole core and reactor control features to ensure safe reactor operation.

  16. Nuclear Transmutations in HFIR's Beryllium Reflector and Their Impact on Reactor Operation and Reflector Disposal

    SciTech Connect

    Chandler, David; Maldonado, G Ivan; Primm, Trent; Proctor, Larry Duane

    2012-01-01

    The High Flux Isotope Reactor located at the Oak Ridge National Laboratory utilizes a large cylindrical beryllium reflector that is subdivided into three concentric regions and encompasses the compact reactor core. Nuclear transmutations caused by neutron activation occur in the beryllium reflector regions, which leads to unwanted neutron absorbing and radiation emitting isotopes. During the past year, two topics related to the HFIR beryllium reflector were reviewed. The first topic included studying the neutron poison (helium-3 and lithium-6) buildup in the reflector regions and its affect on beginning-of-cycle reactivity. A new methodology was developed to predict the reactivity impact and estimated symmetrical critical control element positions as a function of outage time between cycles due to helium-3 buildup and was shown to be in better agreement with actual symmetrical critical control element position data than the current methodology. The second topic included studying the composition of the beryllium reflector regions at discharge as well as during decay to assess the viability of transporting, storing, and ultimately disposing the reflector regions currently stored in the spent fuel pool. The post-irradiation curie inventories were used to determine whether the reflector regions are discharged as transuranic waste or become transuranic waste during the decay period for disposal purposes and to determine the nuclear hazard category, which may affect the controls invoked for transportation and temporary storage. Two of the reflector regions were determined to be transuranic waste at discharge and the other region was determined to become transuranic waste in less than 2 years after being discharged due to the initial uranium content (0.0044 weight percent uranium). It was also concluded that all three of the reflector regions could be classified as nuclear hazard category 3 (potential for localized consequences only).

  17. Electrical property studies of oxygen in Czochralski-grown neutron-transmutation-doped silicon

    SciTech Connect

    Cleland, J.W.; Fukuoka, N.

    1980-10-01

    Electically active oxygen-related donors can be formed in Czochralski (Cz) Si either during crystal growth or during subsequent heat treatment; conventional n- or p-type dopant carrier concentrations are altered if these oxygen donors are present. Neutron transmutation doping (NTD) has been used to introduce a uniform concentration of /sup 31/P in Si. However, oxygen donors can also be formed in NTD Cz Si during the process of annealing to remove NTD radiation damage. In the present experiments, the carrier concentration of Cz and NTD Cz Si samples was determined as a function of the initial dopant, oxygen, and /sup 31/P concentration before and after isothermal or isochronal annealing. It is shown that low temperature (350 to 500/sup 0/C) heat treatment can introduce a significant oxygen donor concentration in Cz Si and in NTD Cz Si that contains radiation-induced lattice defects. Intermediate temperature (550 to 750/sup 0/C) heat treatment, which is intended to remove oxygen donors or lattice defects, can introduce other oxygen donors; annealing above 750/sup 0/C is required to remove any of these oxygen donors. Extended (20 h) high-temperature (1000 to 1200/sup 0/C) annealing can remove oxygen donors and lattice defects, but a significant concentration of oxygen donors can still be introduced by subsequent low temperature heat treatment. These results suggest that oxygen-related donor formation in NTD Cz Si at temperatures below 750/sup 0/C may serve to mask any annealing study of lattice defects. It is concluded that annealing for 30 min at 750/sup 0/C is sufficient to remove radiation damage in NTD Cz Si when the separate effects of oxygen donor formation are included.

  18. Summary Report on New Transmutation Analysis for the Evaluation of Homogeneous and Heterogeneous Options in Fast Reactors

    SciTech Connect

    R. M. Ferrer; S. Bays; M. Pope; B. Forget; W. Skerjanc; M. Asgari

    2008-08-01

    A 1000 MWth commercial-scale Sodium Fast Reactor (SFR) design was selected as the baseline in this scenario study. Traditional approaches to Light Water Reactor (LWR) Spent Nuclear Fuel (SNF) transuranic waste (TRU) burning in a fast spectrum system have typically focused on the continual homogeneous recycling (reprocessing) of the discharge fast reactor fuel. The effective reduction of transuranic inventories has been quantified through the use of the transuranics conversion ratio (TRU CR). The implicit assumption in the use of this single parameter is a homogeneous fast reactor option where equal weight is given to the destruction of transuranics, either by fission or eventual fission via transmutation. This work explores the potential application of alternative fast reactor fuel cycles in which the minor actinide (MA) component of the TRU is considered ‘waste’, while the plutonium component is considered as fuel. Specifically, a set of potential designs that incorporate radial heterogeneous target assemblies is proposed and results relevant to transmutation and system analysis are presented. In this work we consider exclusively minor actinide-bearing radial targets in a continual reprocessing scenario (as opposed to deep-burn options). The potential use of targets in a deep burn mode is not necessarily ruled out as an option. However, due to work scope constraints and material limit considerations, it was preferred to leave the target assemblies reach either the assumed limit of 200 DPA at discharge or maximum allowable gas pressure caused by helium production from transmutation. The number and specific design of the target assemblies was chosen to satisfy the necessary core symmetry and physical dimensions (available space for a certain amount of mass in an assembly based on an iterated mass density).

  19. LWR fuel assembly designs for the transmutation of LWR Spent Fuel TRU with FCM and UO{sub 2}-ThO{sub 2} Fuels

    SciTech Connect

    Bae, G.; Hong, S. G.

    2013-07-01

    In this paper, transmutation of transuranic (TRU) nuclides from LWR spent fuels is studied by using LWR fuel assemblies which consist of UO{sub 2}-ThO{sub 2} fuel pins and FCM (Fully Ceramic Microencapsulated) fuel pins. TRU from LWR spent fuel is loaded in the kernels of the TRISO particle fuels of FCM fuel pins. In the FCM fuel pins, the TRISO particle fuels are distributed in SiC matrix having high thermal conductivity. The loading patterns of fuel pins and the fuel compositions are searched to have high transmutation rate and feasible neutronic parameters including pin power peaking, temperature reactivity coefficients, and cycle length. All studies are done only in fuel assembly calculation level. The results show that our fuel assembly designs have good transmutation performances without multi-recycling and without degradation of the safety-related neutronic parameters. (authors)

  20. Front-end and back-end electrochemistry of molten salt in accelerator-driven transmutation systems

    SciTech Connect

    Williamson, M.A.; Venneri, F.

    1995-07-01

    The objective of this work is to develop preparation and clean-up processes for the fuel and carrier salt in the Los Alamos Accelerator-Driven Transmutation Technology molten salt nuclear system. The front-end or fuel preparation process focuses on the removal of fission products, uranium, and zirconium from spent nuclear fuel by utilizing electrochemical methods (i.e., electrowinning). The same method provides the separation of the so-called noble metal fission products at the back-end of the fuel cycle. Both implementations would have important diversion safeguards. The proposed separation processes and a thermodynamic analysis of the electrochemical separation method are presented.

  1. Multiple rod-cone and cone-rod photoreceptor transmutations in snakes: evidence from visual opsin gene expression.

    PubMed

    Simões, Bruno F; Sampaio, Filipa L; Loew, Ellis R; Sanders, Kate L; Fisher, Robert N; Hart, Nathan S; Hunt, David M; Partridge, Julian C; Gower, David J

    2016-01-27

    In 1934, Gordon Walls forwarded his radical theory of retinal photoreceptor 'transmutation'. This proposed that rods and cones used for scotopic and photopic vision, respectively, were not fixed but could evolve into each other via a series of morphologically distinguishable intermediates. Walls' prime evidence came from series of diurnal and nocturnal geckos and snakes that appeared to have pure-cone or pure-rod retinas (in forms that Walls believed evolved from ancestors with the reverse complement) or which possessed intermediate photoreceptor cells. Walls was limited in testing his theory because the precise identity of visual pigments present in photoreceptors was then unknown. Subsequent molecular research has hitherto neglected this topic but presents new opportunities. We identify three visual opsin genes, rh1, sws1 and lws, in retinal mRNA of an ecologically and taxonomically diverse sample of snakes central to Walls' theory. We conclude that photoreceptors with superficially rod- or cone-like morphology are not limited to containing scotopic or photopic opsins, respectively. Walls' theory is essentially correct, and more research is needed to identify the patterns, processes and functional implications of transmutation. Future research will help to clarify the fundamental properties and physiology of photoreceptors adapted to function in different light levels. PMID:26817768

  2. Flibe blanket concept for transmuting transuranic elements and long lived fission products.

    SciTech Connect

    Gohar, Y.

    2000-11-15

    A Molten salt (Flibe) fusion blanket concept has been developed to solve the disposition problems of the spent nuclear fuel and the transuranic elements. This blanket concept can achieve the top rated solution, the complete elimination of the transuranic elements and the long-lived fission products. Small driven fusion devices with low neutron wall loading and low neutron fluence can perform this function. A 344-MW integrated fusion power from D-T plasmas for thirty years with an availability factor of 0.75 can dispose of 70,000 tons of the US inventory of spent nuclear fuel generated up to the year 2015. In addition, the utilization of this blanket concept eliminates the need for a geological repository site, which is a major advantage. This application provides an excellent opportunity to develop and to enhance the public acceptance of the fusion energy for the future. The energy from the transmutation process is utilized to produce revenue. Flibe, lithium-lead eutectic, and liquid lead are possible candidates. The liquid blankets have several features, which are suited for W application. It can operate at constant thermal power without interruption for refueling by adjusting the concentration of the transuranic elements and lithium-6. These liquids operate at low-pressure, which reduces the primary stresses in the structure material. Development and fabrication costs of solid transuranic materials are eliminated. Burnup limit of the transuranic elements due to radiation effects is eliminated. Heat is generated within the liquid, which simplifies the heat removal process without producing thermal stresses. These blanket concepts have large negative temperature coefficient with respect to the blanket reactivity, which enhances the safety performance. These liquids are chemically and thermally stable under irradiation conditions, which minimize the radioactive waste volume. The operational record of the Molten Salt Breeder Reactor with Flibe was very successful

  3. Assessment of General Atomics accelerator transmutation of waste concept based on gas-turbine-modular helium cooled reactor technology.

    SciTech Connect

    Gohar, Y.; Taiwo, T. A.; Cahalan, J. E.; Finck, P. J.

    2001-05-08

    An assessment has been performed for an Accelerator Transmutation of Waste (ATW) concept based on the use of the high temperature gas reactor technology. The concept has been proposed by General Atomics for the ATW system. The assessment was jointly conducted at Argonne National Laboratory (ANL) and Los Alamos national laboratory to assess and to define the potential candidates for the ATW system. This report represents the assessment work performed at ANL. The concept uses recycled light water reactor (LWR)-discharge-transuranic extracted from irradiated oxide fuel in a critical and sub-critical accelerator driven gas-cooled transmuter. In this concept, the transmuter operates at 600 MWt first in the critical mode for three cycles and then operates in a subcritical accelerator-driven mode for a single cycle. The transmuter contains both thermal and fast spectrum transmutation zones. The thermal zone is fueled with the TRU oxide material in the form of coated particles, which are mixed with graphite powder, packed into cylindrical compacts, and loaded in hexagonal graphite blocks with cylindrical channels; the fast zone is fueled with TRU-oxide material in the form of coated particles without the graphite powder and the graphite blocks that has been burned in the thermal region for three critical cycles and one additional accelerator-driven cycle. The fuel loaded into the fast zone is irradiated for four additional cycles. This fuel management scheme is intended to achieve a high Pu isotopes consumption in the thermal spectrum zone, and to consume the minor actinides in the fast-spectrum zone. Monte Carlo and deterministic codes have been used to assess the system performance and to determine the feasibility of achieving high TRU consumption levels. The studies revealed the potential for high consumption of Pu-239 (97%), total Pu (71%) and total TRU (64%) in the system. The analyses confirmed the need for burnable absorber for both suppressing the initial excess

  4. FIRST-PRINCIPLES CALCULATIONS OF CHARGE STATES AND FORMATION ENERGIES OF Mg, Al, and Be TRANSMUTANTS IN 3C-SiC

    SciTech Connect

    Hu, Shenyang Y.; Setyawan, Wahyu; Jiang, Weilin; Henager, Charles H.; Kurtz, Richard J.

    2014-08-28

    The Vienna Ab-initio Simulation Package (VASP) is employed to calculate charge states and the formation energies of Mg, Al and Be transmutants at different lattice sites in 3C-SiC. The results provide important information on the dependence of the most stable charge state and formation energy of Mg, Al, Be and vacancies on electron potentials.

  5. Copper doping of ZnO crystals by transmutation of {sup 64}Zn to {sup 65}Cu: An electron paramagnetic resonance and gamma spectroscopy study

    SciTech Connect

    Recker, M. C.; McClory, J. W. Holston, M. S.; Golden, E. M.; Giles, N. C.; Halliburton, L. E.

    2014-06-28

    Transmutation of {sup 64}Zn to {sup 65}Cu has been observed in a ZnO crystal irradiated with neutrons. The crystal was characterized with electron paramagnetic resonance (EPR) before and after the irradiation and with gamma spectroscopy after the irradiation. Major features in the gamma spectrum of the neutron-irradiated crystal included the primary 1115.5 keV gamma ray from the {sup 65}Zn decay and the positron annihilation peak at 511 keV. Their presence confirmed the successful transmutation of {sup 64}Zn nuclei to {sup 65}Cu. Additional direct evidence for transmutation was obtained from the EPR of Cu{sup 2+} ions (where {sup 63}Cu and {sup 65}Cu hyperfine lines are easily resolved). A spectrum from isolated Cu{sup 2+} (3d{sup 9}) ions acquired after the neutron irradiation showed only hyperfine lines from {sup 65}Cu nuclei. The absence of {sup 63}Cu lines in this Cu{sup 2+} spectrum left no doubt that the observed {sup 65}Cu signals were due to transmuted {sup 65}Cu nuclei created as a result of the neutron irradiation. Small concentrations of copper, in the form of Cu{sup +}-H complexes, were inadvertently present in our as-grown ZnO crystal. These Cu{sup +}-H complexes are not affected by the neutron irradiation, but they dissociate when a crystal is heated to 900 °C. This behavior allowed EPR to distinguish between the copper initially in the crystal and the copper subsequently produced by the neutron irradiation. In addition to transmutation, a second major effect of the neutron irradiation was the formation of zinc and oxygen vacancies by displacement. These vacancies were observed with EPR.

  6. Transmutation of {sup 99}Tc in a low lethargy medium as a function of the neutron energy

    SciTech Connect

    Abanades, A.; Garcia, J.; Perlado, M.; Aleixandre, J.; Bueno, J.; Cerro, E.; Gonzalez, O.; Tamarit, J.; Andriamonje, S.; Arnould, H.; Bompas, C. A.; Del Moral, R.; Lacoste, V.; Angelopoulous, A.; Apostolakis, A.; Sakelariou, K.; Sakelliou, L.; Zarris, G.; Belle, E.; Giorni, A.

    1998-10-26

    In the TARC experiment the differential neutron flux {phi}(E,r-vector) of a spallation of 2.5 and 3.5 GeV/c proton in large lead block is measured in the range between 0.1 eV and 1.5 MeV. A new technique, using small quantities (less than 0.1 gram) of material, is used for measuring the transmutation rate as a function of neutron energy in the range between 0.1 eV up to a few keV. The method is applied to a target of 86 mg ({sup 99}Tc) mixed with 1.7 g of Aluminum. From these measurements the energy profile of the capture cross section can be extracted.

  7. A theoretical model for the production of Ac-225 for cancer therapy by neutron capture transmutation of Ra-226.

    PubMed

    Melville, G; Melville, P

    2013-02-01

    Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. We are investigating the reduction of radium by transmutation by bombarding Ra-226 with high-energy neutrons from a neutron source to produce Ra-225 and hence Ac-225, which can be used as a generator to produce Bi-213 for use in 'Targeted Alpha Therapy' for cancer. This paper examines the possibility of producing Ac-225 by neutron capture using a theoretical model in which neutron energy is convoluted with the corresponding neutron cross sections of Ra-226. The total integrated yield can then be obtained. This study shows that an intense beam of high-energy neutrons could initiate neutron capture on Ra-226 to produce Ra-225 and hence practical amounts of Ac-225 and a useful reduction of Ra-226. PMID:23220026

  8. Actinide partitioning-transmutation program final report. VII. Long-term risk analysis of the geologic repository

    SciTech Connect

    Logan, S.E.; Conarty, R.L.; Ng, H.S.; Rahal, L.J.; Shirley, C.G.

    1980-09-01

    This report supports the overall assessment by Oak Ridge National Laboratory of actinide partitioning and transmutation by providing an analysis of the long-term risks associated with the terminal storage of wastes from a fuel cycle which incorporates partitioning and transmutation (P-T) and wastes from a cycle which does not. The system model and associated computer code, called AMRAW (Assessment Method for Radioactive Waste), are used for the analysis and are applied to the Los Medanos area in southeastern New Mexico. Because a conservative approach is used throughout, calculated results are believed to be consistently higher than reasonable expectations from actual disruptive incidents at the site and therefore are not directly suited for comparison with other analyses of the particular geologic location. The assessment is made with (1) the probabilistic, or risk, mode that uses combinations of reasonable possible release incidents with their probability of occurrence distributed and applied throughout the assessment period, and (2) the consequence mode that forces discrete release events to occur at specific times. An assessment period of 1 million years is used. The principal results are: (1) In all but the expulsive modes, /sup 99/Tc and /sup 129/I completely dominate cumulative effects based on their transport to man through leaching and movement with groundwater, effecting about 33,000 health effects (deaths) over the 1 million years; (2) P-T has only limited effectiveness in reducing long-term risk from a radionuclide waste repository under the conditions studied, and such effectiveness is essentially confined to the extremely unlikely (probability of occurrence 10/sup -12//year) expulsive events; (3) Removal or immobilization of /sup 99/Tc and /sup 129/I might provide benefits sufficiently tangible to warrant special consideration.

  9. Actinide partitioning-transmutation program final report. VI. Short-term risk analysis of reprocessing, refabrication, and transportation: summary

    SciTech Connect

    Fullwood, R.; Jackson, R.

    1980-03-01

    A Partitioning-Transmutation (PT) fuel cycle is being compared to a Reference cycle employing conventional fuel-material recovery methods. The PT cycle uses enhanced recovery methods so that most of the long-lived actinides are recycled to nuclear power plants and transmuted thereby reducing the waste toxicity. This report compares the two fuel cycles on the basis of the short-term radiological and nonradiological risks. The accidental radiological risk to the public is analyzed by estimating the probabilities of sets of accidents; the consequences are calculated using the risk, which is RAC code. Routine radiological risks to the public are estimated from the calculated release amounts, also using the CRAC code. Radiological occupational risks are determined from prior experience, projected standards, and estimates of accident risk. Nonradiological risks are calculated from the number of personnel involved, historical experience, and epidemiological studies. Result of this analysis is that the short-term risk of PT is 2.9 times greater than that of the Reference cycle, primarily due to the larger amount of industry. The nonradiological risk which is about 150 times greater than the radiological risk. If the radiological risk is consdered alone, the ratio of PT to Reference risk is 3, composed as follows: radiological operations affecting the public 5, radiological operations affecting the workers 1.7, and radiological accidents affecting the public 1.4, all in the order of decreasing risk. The absolute risk as estimated for the fuel cycle portions considered in this report is 0.91 fatality/GWe-year for the PT cycle and 0.34 fatality/GWe-year for the reference cycle; this compares with 1.5 for nuclear and 150 for coal. All of the risks assumed here are associated with the production of one billion watts of electricity (GWe) per year.

  10. Actinide partitioning-transmutation program final report. VI. Short-term risk analysis of reprocessing, refabrication, and transportation: appendix

    SciTech Connect

    Fullwood, R.R.; Jackson, R.

    1980-01-01

    The Chemical Technology Division of the Oak Ridge National Laboratory has prepared a set of documents that evaluate a Partitioning-Transmutation (PT) fuel cycle relative to a Reference cycle employing conventional fuel-material recovery methods. The PT cycle uses enhanced recovery methods so that most of the long-lived actinides are recycled to nuclear power plants and transmuted to shorter-lived materials, thereby reducing the waste toxicity. This report compares the two fuel cycles on the basis of the short-term radiological and nonradiological risks they present to the public and to workers. The accidental radiological risk to the public is analyzed by estimating the probabilities of sets of accidents; the consequences are calculated using the CRAC code appropriately modified for the material composition. Routine radiological risks to the public are estimated from the calculated release amounts; the effects are calculated using the CRAC code. Radiological occupational risks are determined from prior experience, projected standards, and estimates of accident risk. Nonradiological risks are calculated from the number of personnel involved, historical experience, and epidemiological studies. The result of this analysis is that the short-term risk of PT is 2.9 times greater than that of the Reference cycle, primarily due to the larger amount of industry. This conclusion is strongly dominated by the nonradiological risk, which is about 150 times greater than the radiological risk. The absolute risk as estimated for the fuel cycle portions considered in this report is 0.91 fatalities/GWe-year for the PT cycle and 0.34 fatalities/GWe-year for the Reference cycle. This should be compared with Inhaber's estimate of 1.5 for nuclear and 150 for coal. All of the risks assumed here are associated with the production of one billion watts of electricity (GWe) per year.

  11. Study on partitioning and transmutation as a possible option for spent fuel management within a nuclear phase-out scenario

    SciTech Connect

    Fazion, C.; Rineiski, A.; Salvatores, M.; Schwenk-Ferrero, A.; Romanello, V.; Vezzoni, B.; Gabrielli, F.

    2013-07-01

    Most Partitioning and Transmutation (PT) studies implicitly presuppose the continuous use of nuclear energy. In this case the development of new facilities or the modification of the fuel cycle can be justified in the long-term as an important feature in order to improve sustainability by minimizing radioactive waste and reducing the burden at waste disposal. In the case of a country with nuclear energy phase-out policy, the PT option might have also an important role for what concerns the final disposal strategies of the spent fuel. In this work three selected scenarios are analyzed in order to assess the impact of PT implementation in a nuclear energy phase out option. The scenarios are: -) Scenario 1: Identification of Research/Development activities needs for a technological development of PT while postponing the decision of PT implementation; -) Scenario 2: Isolated application of PT in a phase-out context; and -) Scenario 3: Implementation of PT in a European context. In order to facilitate the discrimination among the 3 scenarios, a number of figures of indicators have been evaluated for each scenario. The selected indicators are: the mass of High Level Waste (HLW), Uranium inventory, thermal output of HLW, Radiotoxicity, Fuel cycle secondary waste associated to the PT operation, and Facility capacity/number requirements. The reduction, due to PT implementation, of high level wastes masses and their associated volumes can be significant. For what concerns the thermal output and radiotoxicity a significant impact can be also expected. However, when assessing these two indicators the contribution coming from already vitrified waste should also not be neglected. Moreover, an increase of secondary waste inventory is also expected. On the contrary, the increase of fission product inventories due to the operation of the transmutation system has a relatively limited impact on the fuel cycle.

  12. Specific features of transmutational doping of {sup 30}Si-enriched silicon crystals with phosphorus: Studies by the method of electron spin resonance

    SciTech Connect

    Baranov, P. G.; Ber, B. Ya.; Godisov, O. N.; Il'in, I. V. Ionov, A. N.; Kaliteevskii, A. K.; Kaliteevskii, M. A.; Lazebnik, I. M.; Safronov, A. Yu.; Pohl, H.-J.; Riemann, H.; Abrosimov, N. V.; Kop'ev, P. S.; Bulanov, A. D.; Gusev, A. V.

    2006-08-15

    Electron spin resonance (ESR) is used to study the neutron transmutation doping of silicon crystals enriched with {sup 30}Si isotope: phosphorus donors and radiation defects produced in the course of transmutational doping are observed. The ESR signals related to the phosphorus uncontrolled impurity in {sup 30}Si before transmutational doping (the P concentration is {approx}10{sup 15} cm{sup -3}) and phosphorus introduced by neutron irradiation with doses {approx}1 x 10{sup 19} cm{sup -2} and {approx}1 x 10{sup 20} cm{sup -2} (the P concentrations are {approx}5 x 10{sup 16} and {approx}7 x 10{sup 17} cm{sup -3}, respectively) are studied. As a result of drastic narrowing of the phosphorus ESR lines in {sup 30}Si, the intensity of lines increased appreciably, which made it possible to measure the phosphorus concentration in the samples with a small volume (down to 10{sup -6} mm{sup -3}). The methods for determining the concentration of P donors from hyperfine structure in the ESR spectra of isolated P atoms, exchange-related pairs, and clusters that consist of three, four, and more P donors are developed. In the region of high concentrations of P donors, in which case the hyperfine structure disappears, the concentration of P donors was estimated from the exchange-narrowed ESR line.

  13. Multiple rod–cone and cone–rod photoreceptor transmutations in snakes: Evidence from visual opsin gene expression

    USGS Publications Warehouse

    Simoe, Bruno F; Sampaio, Filipa L.; Loew, Ellis R.; Sanders, Kate L.; Fisher, Robert N.; Hart, Nathan S.; Hunt, David M.; Partridge, Julian C.; Gower, David J.

    2016-01-01

    In 1934, Gordon Walls forwarded his radical theory of retinal photoreceptor ‘transmutation’. This proposed that rods and cones used for scotopic and photopic vision, respectively, were not fixed but could evolve into each other via a series of morphologically distinguishable intermediates. Walls' prime evidence came from series of diurnal and nocturnal geckos and snakes that appeared to have pure-cone or pure-rod retinas (in forms that Walls believed evolved from ancestors with the reverse complement) or which possessed intermediate photoreceptor cells. Walls was limited in testing his theory because the precise identity of visual pigments present in photoreceptors was then unknown. Subsequent molecular research has hitherto neglected this topic but presents new opportunities. We identify three visual opsin genes, rh1, sws1 and lws, in retinal mRNA of an ecologically and taxonomically diverse sample of snakes central to Walls' theory. We conclude that photoreceptors with superficially rod- or cone-like morphology are not limited to containing scotopic or photopic opsins, respectively. Walls' theory is essentially correct, and more research is needed to identify the patterns, processes and functional implications of transmutation. Future research will help to clarify the fundamental properties and physiology of photoreceptors adapted to function in different light levels.

  14. A measurement of actinide neutron transmutations with accelerator mass spectrometry in order to infer neutron capture cross sections

    NASA Astrophysics Data System (ADS)

    Bauder, William K.

    Improved neutron capture cross section data for transuranic and minor actinides are essential for assessing possibilities for next generation reactors and advanced fuel cycles. The Measurement of Actinide Neutron TRAnsmutation (MANTRA) project aims to make a comprehensive set of energy integrated neutron capture cross section measurements for all relevant isotopes from Th to Cf. The ability to extract these cross sections relies on the use of Accelerator Mass Spectrometry (AMS) to analyze isotopic concentrations in samples irradiated in the Advanced Test Reactor (ATR). The AMS measurements were performed at the Argonne Tandem Linear Accelerator System (ATLAS) and required a number of key technical developments to the ion source, accelerator, and detector setup. In particular, a laser ablation material injection system was developed at the electron cyclotron resonance ion source. This system provides a more effective method to produce ion beams from samples containing only 1% actinide material and offers some benefits for reducing cross talk in the source. A series of four actinide measurements are described in this dissertation. These measurements represent the most substantial AMS work attempted at ATLAS and the first results of the MANTRA project. Isotopic ratios for one and two neutron captures were measured in each sample with total uncertainties around 10%. These results can be combined with a MCNP model for the neutron fluence to infer actinide neutron capture cross sections.

  15. Predicting thermo-mechanical behaviour of high minor actinide content composite oxide fuel in a dedicated transmutation facility

    NASA Astrophysics Data System (ADS)

    Lemehov, S. E.; Sobolev, V. P.; Verwerft, M.

    2011-09-01

    The European Facility for Industrial Transmutation (EFIT) of the minor actinides (MA), from LWR spent fuel is being developed in the integrated project EUROTRANS within the 6th Framework Program of EURATOM. Two composite uranium-free fuel systems, containing a large fraction of MA, are proposed as the main candidates: a CERCER with magnesia matrix hosting (Pu,MA)O 2-x particles, and a CERMET with metallic molybdenum matrix. The long-term thermal and mechanical behaviour of the fuel under the expected EFIT operating conditions is one of the critical issues in the core design. To make a reliable prediction of long-term thermo-mechanical behaviour of the hottest fuel rods in the lead-cooled version of EFIT with thermal power of 400 MW, different fuel performance codes have been used. This study describes the main results of modelling the thermo-mechanical behaviour of the hottest CERCER fuel rods with the fuel performance code MACROS which indicate that the CERCER fuel residence time can safely reach at least 4-5 effective full power years.

  16. A theoretical model for the production of Ac-225 for cancer therapy by photon-induced transmutation of Ra-226.

    PubMed

    Melville, G; Fan Liu, Sau; Allen, B J

    2006-09-01

    Radium needles that were once implanted into tumours as a cancer treatment are now obsolete and constitute a radioactive waste problem, as their half-life is 1600 years. We are investigating the reduction of radium by transmutation on a small scale by bombarding Ra-226 with high-energy photons from a medical linear accelerator (linac) to produce Ra-225, which subsequently decays to Ac-225, which can be used as a generator to produce Bi-213 for use in 'targeted alpha therapy' for cancer. This paper examines the possibility of producing Ac-225 with a linac using an accurate theoretical model in which the bremsstrahlung photon spectrum at 18 MV linac electron energy is convoluted with the corresponding photonuclear cross sections of Ra-226. The total integrated yield can then be obtained and is compared with a computer simulation. This study shows that at 18 MV, the photonuclear reaction on Ra-226 can produce low activities of Ac-225 with a linac. However, a high power linac with high current, pulse length and frequency is needed to produce practical amounts of Ac-225 and a useful reduction of Ra-226. PMID:16806950

  17. Effects of silicon cross section and neutron spectrum on the radial uniformity in neutron transmutation doping.

    PubMed

    Kim, Haksung; Ho Pyeon, Cheol; Lim, Jae-Yong; Misawa, Tsuyoshi

    2012-01-01

    The effects of silicon cross section and neutron spectrum on the radial uniformity of a Si-ingot are examined experimentally with various neutron spectrum conditions. For the cross section effect, the numerical results using silicon single crystal cross section reveal good agreements with experiments within relative difference of 6%, whereas the discrepancy is approximately 20% in free-gas cross section. For the neutron spectrum effect, the radial uniformity in hard neutron spectrum is found to be more flattening than that in soft spectrum. PMID:21917470

  18. Theoretical and Experimental Results Regarding LENR/CF

    SciTech Connect

    Robert W. Bass; Wm. Stan Gleeson

    2000-11-12

    We challenge the predominant view that low-energy nuclear reactions (LENRs) are prohibited by standard quantum mechanics (QM). This view, supposedly based on standard nuclear theory, need not apply in condensed-matter environments. These considerations indicate that seemingly novel experimental evidence of rapid aneutronic bulk-process transmutation, at extraordinarily low-energy levels, in a simple electrochemical reactor, can occur. This explains: (a) induced rapid decay of radioactive thorium into stable nuclides, e.g., Cu and (b) resulting, anomalous distribution of Cu isotopes. We reexamine arguments of Peebles cited as evidence that standard QM 'forbids' cold fusion (CF). We note oversimplifications in those and present an alternative, more sophisticated calculation (see Bass, Refs. 3 through 8) demonstrating that conventional wisdom about impenetrability of the 'Coulomb barrier' fails as a result of periodic-order-induced resonance. We also examine empirical evidence. In three independent tests of an LENR electrolysis cell, using different I-V-T (current/voltage/time) protocols, the percentage of radiation reduction (RR) transmutation achieved {eta}=[23{percent}, 50{percent}, 83{percent}] versus expended energy E=[0.6535, 32.5, 74.6] (Watt-hours), obtained by numerical integration of recorded product I{center_dot}V for processing time T, provides near-perfect straight-line correlation: {eta}={alpha}{center_dot}E + {eta}{sub 0}, {alpha}=0.8105, {eta}{sub 0}=22.888, (0.65 < E < 0.75).

  19. Analyses in Support of Z-Pinch IFE and Actinide Transmutation - LLNL Progress Report for FY-06

    SciTech Connect

    Meier, W R; Moir, R W; Abbott, R

    2006-09-19

    This report documents results of LLNL's work in support of two studies being conducted by Sandia National Laboratories (SNL): the development of the Z-pinch driven inertial fusion energy (Z-IFE), and the use of Z-pinch driven inertial fusion as a neutron source to destroy actinides from fission reactor spent fuel. LLNL's efforts in FY06 included: (1) Development of a systems code for Z-IFE and use of the code to examine the operating parameter space in terms of design variables such as the Z-pinch driver energy, the chamber pulse repetition rate, the number of chambers making up the power plant, and the total net electric power of the plant. This is covered in Section 3 with full documentation of the model in Appendix A. (2) Continued development of innovative concepts for the design and operation of the recyclable transmission line (RTL) and chamber for Z-IFE. The work, which builds on our FY04 and FY05 contributions, emphasizes design features that are likely to lead to a more attractive power plant including: liquid jets to protect all structures from direct exposure to neutrons, rapid insertion of the RTL to maximize the potential chamber rep-rate, and use of cast flibe for the RTL to reduce recycling and remanufacturing costs and power needs. See Section 4 and Appendix B. (3) Description of potential figures of merit (FOMs) for actinide transmutation technologies and a discussion of how these FOMs apply and can be used in the ongoing evaluation of the Z-pinch actinide burner, referred to as the In-Zinerator. See Section 5. (4) A critique of, and suggested improvements to, the In-Zinerator chamber design in response to the SNL design team's request for feedback on its preliminary design. This is covered in Section 6.

  20. EASY-II: a system for modelling of n, d, p, γ and α activation and transmutation processes

    NASA Astrophysics Data System (ADS)

    Sublet, Jean-Christophe; Eastwood, James; Morgan, Guy; Koning, Arjan; Rochman, Dimitri

    2014-06-01

    EASY-II is designed as a functional replacement for the previous European Activation System, EASY-2010. It has extended nuclear data and new software, FISPACT-II, written in object-style Fortran to provide new capabilities for predictions of activation, transmutation, depletion and burnup. The new FISPACT-II code has allowed us to implement many more features in terms of energy range, up to GeV; incident particles: alpha, gamma, proton, deuteron and neutron; and neutron physics: self-shielding effects, temperature dependence, pathways analysis, sensitivity and error estimation using covariance data. These capabilities cover most application needs: nuclear fission and fusion, accelerator physics, isotope production, waste management and many more. In parallel, the maturity of modern general-purpose libraries such as TENDL-2012 encompassing thousands of target nuclides, the evolution of the ENDF format and the capabilities of the latest generation of processing codes PREPRO-2012, NJOY2012 and CALENDF-2010 have allowed the FISPACT-II code to be fed with more robust, complete and appropriate data: cross-sections with covariance, probability tables in the resonance ranges, kerma, dpa, gas and radionuclide production and 24 decay types. All such data for the five most important incident particles are placed in evaluated data files up to an incident energy of 200 MeV. The resulting code and data system, EASY-II, includes many new features and enhancements. It has been extensively tested, and also benefits from the feedback from wide-ranging validation and verification activities performed with its predecessor

  1. Transmutation of high-level radioactive waste and production of {sup 233}U using an accelerator-driven reactor

    SciTech Connect

    Takahashi, Hiroshi; Takashita, Hirofumi; Chen, Xinyi

    1994-08-01

    Reactor safety, the disposal of high-level nuclear waste, and nonproliferation of nuclear material for military purposes are the problems of greatest concern for nuclear energy. Technologies for accelerators developed in the field of high-energy physics can contribute to solving these problems. For reactor safety, especially for that of a Na-cooled fast reactor, the use of an accelerator, even a small one, can enhance the safety using a slightly subcritical reactor. There is growing concern about how we can deal with weapons-grade Pu, and about the large amount of Pu accumulating from the operation of commercial reactors. It has been suggested that this Pu could be incinerated, using the reactor and a proton accelerator. However, because Pu is a very valuable material with future potential for generating nuclear energy, we should consider transforming it into a proliferation-resistant material that cannot be used for making bombs, rather than simply eliminating the Pu. An accelerator-driven fast reactor (700 MWt), run in a subcritical condition, and fueled with MOX can generate {sup 233}U more safely and efficiently than can a critical reactor. We evaluate the production of {sup 233}U, {sup 239}Pu, and the transmutation of the long-lived fission products of {sup 99}Tc and {sup 129}I, which are loaded with YH{sub 1.7} between the fast core and blanket, by reducing the conversion factor of Pu to {sup 233}U. And we assessed the rates of radiation damage, hydrogen production, and helium production in a target window and in the surrounding vessel.

  2. Preparation of a technology development roadmap for the Accelerator Transmutation of Waste (ATW) System : report of the ATW separations technologies and waste forms technical working group.

    SciTech Connect

    Collins, E.; Duguid, J.; Henry, R.; Karell, E.; Laidler, J.; McDeavitt, S.; Thompson, M.; Toth, M.; Williamson, M.; Willit, J.

    1999-08-12

    In response to a Congressional mandate to prepare a roadmap for the development of Accelerator Transmutation of Waste (ATW) technology, a Technical Working Group comprised of members from various DOE laboratories was convened in March 1999 for the purpose of preparing that part of the technology development roadmap dealing with the separation of certain radionuclides for transmutation and the disposal of residual radioactive wastes from these partitioning operations. The Technical Working Group for ATW Separations Technologies and Waste Forms completed its work in June 1999, having carefully considered the technology options available. A baseline process flowsheet and backup process were identified for initial emphasis in a future research, development and demonstration program. The baseline process combines aqueous and pyrochemical processes to permit the efficient separation of the uranium, technetium, iodine and transuranic elements from the light water reactor (LWR) fuel in the head-end step. The backup process is an all- pyrochemical system. In conjunction with the aqueous process, the baseline flowsheet includes a pyrochemical process to prepare the transuranic material for fabrication of the ATW fuel assemblies. For the internal ATW fuel cycle the baseline process specifies another pyrochemical process to extract the transuranic elements, Tc and 1 from the ATW fuel. Fission products not separated for transmutation and trace amounts of actinide elements would be directed to two high-level waste forms, one a zirconium-based alloy and the other a glass/sodalite composite. Baseline cost and schedule estimates are provided for a RD&D program that would provide a full-scale demonstration of the complete separations and waste production flowsheet within 20 years.

  3. Mixtures of Charged Bosons Confined in Harmonic Traps and Bose-Einstein Condensation Mechanism for Low-Energy Nuclear Reactions and Transmutation Processes in Condensed Matters

    NASA Astrophysics Data System (ADS)

    Kim, Yeong E.; Zubarev, Alexander L.

    2006-02-01

    A mixture of two different species of positively charged bosons in harmonic traps is considered in the mean-field approximation. It is shown that depending on the ratio of parameters, the two components may coexist in same regions of space, in spite of the Coulomb repulsion between the two species. Application of this result is discussed for the generalization of the Bose-Einstein condensation mechanism for low-energy nuclear reaction (LENR) and transmutation processes in condensed matters. For the case of deutron-lithium (d + Li) LENR, the result indicates that (d + 6Li) reactions may dominate over (d + d) reactions in LENR experiments.

  4. Unifying Theory of Low-Energy Nuclear Reaction and Transmutation Processes in Deuterated/hydrogenated Metals, Acoustic Cavitation, Glow Discharge, and Deuteron Beam Experiments

    NASA Astrophysics Data System (ADS)

    Kim, Yeong E.; Zubarev, Alexander L.

    The most basic theoretical challenge for understanding low-energy nuclear reaction (LENR) and transmutation reaction (LETR) in condensed matters is to find mechanisms by which the large Coulomb barrier between fusing nuclei can be overcome. A unifying theory of LENR and LETR has been developed to provide possible mechanisms for the LENR and LETR processes in matters based on high-density nano-scale and micro-scale quantum plasmas. It is shown that recently developed theoretical models based on Bose-Einstein Fusion (BEF) mechanism and Quantum Plasma Nuclear Fusion (QPNF) mechanism are applicable to the results of many different types of LENR and LETR experiments.

  5. Conceptual design of experimental equipment for large-diameter NTD-Si.

    PubMed

    Yagi, M; Watanabe, M; Ohyama, K; Yamamoto, K; Komeda, M; Kashima, Y; Yamashita, K

    2009-01-01

    An irradiation-experimental equipment for 12in neutron transmutation doping silicon (NTD-Si) was designed conceptually by using MCNP5 in order to improve the neutron flux distribution of the radial direction. As a result of the calculations, the neutron absorption reaction ratio of the circumference to the center could be limited within 1.09 using a thermal neutron filter that covers the surface of the silicon ingot. The uniformity of the (30)Si neutron absorption was less than 5.3%. PMID:19299158

  6. An experimental paradigm opening the world of superheavy elements

    NASA Astrophysics Data System (ADS)

    Armbruster, P.; Münzenberg, Gottfried

    2012-07-01

    The history of the discovery of the six elements Z = 107 ∓ 112, bohrium, hassium, meitnerium, darmstadtium, roentgenium, and copernicium goes back to the early 1960s. An experimental method to separate and identify rare nuclear reaction products, the recoil separation, was developed and optimised for beams of fission products at European research reactors. Chemical elements beyond the then first transactinides ( Z = 104), which owe their stability to the internal structure of atomic nuclei, were predicted theoretically. A big brother of the shell-stabilised nucleus 208Pb, a spherical magic nucleus at Z = 114∓126 and N = 184, might reach lifetimes long enough to be detected. In the seventies, hunting superheavy elements (SHE) was on the agenda of nuclear chemistry. Could the Periodic Table of Elements be extended to Z = 120, and is the order of electrons in the atom still following the laws established for lighter elements? In Germany, the heavy ion accelerator (UNILAC) was built by Christoph Schmelzer and his team at GSI, Darmstadt. SHE and UNILAC met the recoil separators in 1968, and SHIP (Separator for Heavy Ion reaction Products) was ready together with the first UNILAC-beams in 1976. Recoil separation is orders of magnitude more sensitive, selective, and faster than earlier methods used to synthesise elements up to seaborgium, Z = 106. The experimental paradigm we introduced opened the world of SHEs. At SHIP we discovered and investigated the elements Z = 107∓112 in the years 1980-2000. Our laboratory was the world champion during this time. Today our experimental method is used worldwide in the search for SHEs, but the leadership went to the Russian laboratory JINR in Dubna, which extended the Periodic Table by 6 more elements to Z = 118, the candidate for the next rare gas.

  7. Accurate determination of Curium and Californium isotopic ratios by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) in 248Cm samples for transmutation studies

    SciTech Connect

    Gourgiotis, A.; Isnard, H.; Aubert, M.; Dupont, E.; AlMahamid, I.; Cassette, P.; Panebianco, S.; Letourneau, A.; Chartier, F.; Tian, G.; Rao, L.; Lukens, W.

    2011-02-01

    The French Atomic Energy Commission has carried out several experiments including the mini-INCA (INcineration of Actinides) project for the study of minor-actinide transmutation processes in high intensity thermal neutron fluxes, in view of proposing solutions to reduce the radiotoxicity of long-lived nuclear wastes. In this context, a Cm sample enriched in {sup 248}Cm ({approx}97 %) was irradiated in thermal neutron flux at the High Flux Reactor (HFR) of the Laue-Langevin Institute (ILL). This work describes a quadrupole ICP-MS (ICP-QMS) analytical procedure for precise and accurate isotopic composition determination of Cm before sample irradiation and of Cm and Cf after sample irradiation. The factors that affect the accuracy and reproducibility of isotopic ratio measurements by ICP-QMS, such as peak centre correction, detector dead time, mass bias, abundance sensitivity and hydrides formation, instrumental background, and memory blank were carefully evaluated and corrected. Uncertainties of the isotopic ratios, taking into account internal precision of isotope ratio measurements, peak tailing, and hydrides formations ranged from 0.3% to 1.3%. This uncertainties range is quite acceptable for the nuclear data to be used in transmutation studies.

  8. Ab initio calculations of mechanical properties of bcc W–Re–Os random alloys: effects of transmutation of W

    NASA Astrophysics Data System (ADS)

    Li, Xiaojie; Schönecker, Stephan; Li, Ruihuan; Li, Xiaoqing; Wang, Yuanyuan; Zhao, Jijun; Johansson, Börje; Vitos, Levente

    2016-07-01

    To examine the effect of neutron transmutation on tungsten as the first wall material of fusion reactors, the elastic properties of W1‑x‑y  Re x  Os y (0  ⩽  x, y  ⩽  6%) random alloys in body centered cubic (bcc) structure are investigated systematically using the all-electron exact muffin-tin orbitals (EMTO) method in combination with the coherent-potential approximation (CPA). The calculated lattice constant and elastic properties of pure W are consistent with available experiments. Both Os and Re additions reduce the lattice constant and increase the bulk modulus of W, with Os having the stronger effect. The polycrystalline shear modulus, Young’s modulus and the Debye temperature increase (decrease) with the addition of Re (Os). Except for C 11, the other elastic parameters including C 12, C 44, Cauchy pressure, Poisson ratio, B/G, increase as a function of Re and Os concentration. The variations of the latter three parameters and the trend in the ratio of cleavage energy to shear modulus for the most dominant slip system indicate that the ductility of the alloy enhances with increasing Re and Os content. The calculated elastic anisotropy of bcc W slightly increases with the concentration of both alloying elements. The estimated melting temperatures of the W–Re–Os alloy suggest that Re or Os addition will reduce the melting temperature of pure W solid. The classical Labusch–Nabarro model for solid-solution hardening predicts larger strengthening effects in W1‑y  Os y than in W1‑x  Re x . A strong correlation between C‧ and the fcc–bcc structural energy difference for W1‑x‑y  Re x  Os y is revealed demonstrating that canonical band structure dictates the alloying effect on C‧. The structural energy difference is exploited to estimate the alloying effect on the ideal tensile strength in the [0 0 1] direction.

  9. Transmuting Resistance to Change

    ERIC Educational Resources Information Center

    Schuetz, Pam; Barr, Jim

    2008-01-01

    Underprepared students have been a significant presence in community colleges for decades. The growing size of this student population and the urgent reality of workforce accountability and other demands that did not exist forty years ago are pushing colleges to find more effective ways to support success for such students. This article steps…

  10. Historical perspective, economic analysis, and regulatory analysis of the impacts of waste partitioning-transmutation on the disposal of radioactive wastes

    SciTech Connect

    Forsberg, C.W.; Croff, A.G.; Kocher, D.C.

    1990-10-01

    Partitioning-transmutation, sometimes called actinide burning, is an alternative approach to high-level radioactive waste management. It consists of removing long-lived radionuclides from wastes and destroying those radionuclides, thus reducing the long-term hazards of radioactive waste. It was studied in detail in the 1970's. New developments in technology and other factors are resulting in a reexamination of this waste management option. This report consists of three papers which summarize the historical work, update the analysis of the costs of waste disposal, and describe current regulatory requirements which might be impacted by P-T. The papers provide a starting point for future research on P-T. 152 refs., 2 figs., 19 tabs.

  11. On-line separators for the Dubna Superheavy Element Factory

    NASA Astrophysics Data System (ADS)

    Popeko, A. G.

    2016-06-01

    The main goal of creation of a Superheavy Element Factory at the Flerov Laboratory of Nuclear Reactions (FLNR) is to sufficiently improve the efficiency of studies on heavy and superheavy nuclei. The factory will be based on a high-current DC-280 cyclotron. The use of beams with the intensity up to 6 ×1013 s-1 (10 pμA) requires effective separators providing high suppression of unwanted reaction products. Following the analysis of the kinematic characteristics of several hundreds of reactions, a conclusion was drawn that it is necessary to construct three separators optimized for specific tasks: a universal gas-filled separator for synthesis and study of the properties of heavy isotopes, a velocity filter for spectroscopic investigations, and a pre-separator for further chemical separation and precise mass measurements.

  12. Experimental Pi.

    ERIC Educational Resources Information Center

    Corris, G.

    1990-01-01

    Discusses the calculation of pi by means of experimental methods. Polygon circle ratios, Archimedes' method, Buffon's needles, a Monte Carlo method, and prime number approaches are used. Presents three BASIC programs for the calculations. (YP)

  13. Experimental philosophy.

    PubMed

    Knobe, Joshua; Buckwalter, Wesley; Nichols, Shaun; Robbins, Philip; Sarkissian, Hagop; Sommers, Tamler

    2012-01-01

    Experimental philosophy is a new interdisciplinary field that uses methods normally associated with psychology to investigate questions normally associated with philosophy. The present review focuses on research in experimental philosophy on four central questions. First, why is it that people's moral judgments appear to influence their intuitions about seemingly nonmoral questions? Second, do people think that moral questions have objective answers, or do they see morality as fundamentally relative? Third, do people believe in free will, and do they see free will as compatible with determinism? Fourth, how do people determine whether an entity is conscious? PMID:21801019

  14. Animal experimentation.

    PubMed

    Kolar, Roman

    2006-01-01

    Millions of animals are used every year in often times extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the "3Rs" concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. The licensing of animal experiments normally requires an ethical evaluation process, often times undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees' members. There is an ongoing societal debate about ethical issues of animal use in science. Existing EU legislation on animal experimentation for cosmetics testing is an example of both the public will for setting clear limits to animal experiments and the need to further critically examine other fields and aspects of animal experimentation. PMID:16501652

  15. Development of the Experimental Setup Dedicated for Alpha, Gamma and Electron Spectroscopy of Heavy Nuclei at FLNR JINR

    SciTech Connect

    Yeremin, A.; Malyshev, O.; Popeko, A.; Lopez-Martens, A.; Hauschild, K.; Dorvaux, O.; Saro, S.; Pantelika, D.

    2010-04-30

    Various types of reactions and identification techniques were applied in the investigation of formation cross sections and decay properties of transuranium elements. The fusion--evaporation reactions with heavy targets, recoil--separation techniques and identification of nuclei by the parent--daughter generic coincidences with the known daughter-nuclei after implantation into position--sensitive detectors were the most successful tools for production and identification of the heaviest elements known presently. This technique may be further improved and presently it may be very promising for the identification of new elements, search for new isotopes and measurement of new decay data for the known nuclei.At the Flerov Laboratory of Nuclear Reactions (JINR, Dubna), investigations of the complete fusion reactions leading to the synthesis of heavy and superheavy nuclei with the use of heavy ion beams from a powerful U400 cyclotron have been an important part of the experimental program. It is planned to upgrade U400 cyclotron of the FLNR, to deliver beams with higher intensities and smooth variation of energies.New experimental set up, the velocity filter, is now developing for synthesis and studies of the decay properties of heavy nuclei. At the focal plane of the separator GABRIELA set up (alpha,beta,gamma detectors array) will be installed.

  16. Experimental macroevolution†

    PubMed Central

    Bell, Graham

    2016-01-01

    The convergence of several disparate research programmes raises the possibility that the long-term evolutionary processes of innovation and radiation may become amenable to laboratory experimentation. Ancestors might be resurrected directly from naturally stored propagules or tissues, or indirectly from the expression of ancestral genes in contemporary genomes. New kinds of organisms might be evolved through artificial selection of major developmental genes. Adaptive radiation can be studied by mimicking major ecological transitions in the laboratory. All of these possibilities are subject to severe quantitative and qualitative limitations. In some cases, however, laboratory experiments may be capable of illuminating the processes responsible for the evolution of new kinds of organisms. PMID:26763705

  17. Experimental macroevolution.

    PubMed

    Bell, Graham

    2016-01-13

    The convergence of several disparate research programmes raises the possibility that the long-term evolutionary processes of innovation and radiation may become amenable to laboratory experimentation. Ancestors might be resurrected directly from naturally stored propagules or tissues, or indirectly from the expression of ancestral genes in contemporary genomes. New kinds of organisms might be evolved through artificial selection of major developmental genes. Adaptive radiation can be studied by mimicking major ecological transitions in the laboratory. All of these possibilities are subject to severe quantitative and qualitative limitations. In some cases, however, laboratory experiments may be capable of illuminating the processes responsible for the evolution of new kinds of organisms. PMID:26763705

  18. Proof-of-Principle Experiment for Compact, Energy Efficient Neutron Source: Enabling Technology for Radioactive Waste Transmutation or Sub-Critical Nuclear Reactors

    NASA Astrophysics Data System (ADS)

    Hershcovitch, Ady; Roser, Thomas; Santarius, John

    2013-10-01

    A novel neutron source is proposed for radioactive waste transmutation or sub-critical nuclear reactors; it's based on injecting 125 keV deuterium beam through 1-inch tube filled with magnetized tritium plasma to generate 14 MeV D-T neutrons. T target thickness is chosen to slow the D ions to 75 keV. At the opposite end of the tube D ion energy is recovered. Each ion source and tube forms a module. Larger systems can be formed from multiple units. As a D beam propagates through T plasma, it is slowed down by plasma electrons, which are consequently heated. Electron temperature rises until heating is balanced by energy losses. Equilibrium electron temperature is the crucial parameter, since higher temperature, leads to lower drag on the ion beam; therefore, larger target thickness is needed to slow deuterons to 75 keV; with consequently higher neutron yield. A proof of principle experiment, to determine the equilibrium electron temperature, can be perform by injecting 62.5 keV hydrogen beam into hydrogen plasma target and measure the equilibrium electron temperature with Thomson scattering. To reduce electron equilibration with target ions, electron pre-heating can be done rather efficiently with 2.45 GHz microwaves. Supported by USDOE under Contract No. DE-AC02-98CH10886.

  19. Thermodynamic and Kinetic Properties of Intrinsic Defects and Mg Transmutants in 3C-SiC Determined by Density Functional Theory

    SciTech Connect

    Hu, Shenyang Y.; Setyawan, Wahyu; Van Ginhoven, Renee M.; Jiang, Weilin; Henager, Charles H.; Kurtz, Richard J.

    2014-02-20

    Density functional theory (DFT) is used to calculate the thermodynamic and kinetic properties of transmutant Mg in 3C-SiC due to high-energy neutron irradiation associated with the fusion nuclear environment. The formation and binding energies of intrinsic defects, Mg-related defects, and clusters in 3C-SiC are systematically calculated. The minimum energy paths and activation energies during point defect migration and small cluster evolution are studied using a generalized solid-state elastic band (G-SSNEB) method with DFT energy calculations. Stable defect structures and possible defect migration mechanisms are identified. The evolution of binding energies during Mg2Si formation demonstrates that the formation of Mg2Si needs to overcome a critical nucleus size and nucleation barrier. It is also found that a compressive stress field exists around the Mg2Si nucleus. These data are important inputs in meso- and macro-scale modeling and experiments to understand and predict the impact of Mg on phase stability, microstructure evolution, and performance of SiC and SiC-based materials during long-term neutron exposures.

  20. Resonance enhancement in the accelerator transmutation of 1.3-day {sup 232}Pa and 2.1-day {sup 238}Np

    SciTech Connect

    Moore, M. S.; Danon, Y.

    1995-09-15

    The suggestion that the transmutation of actinide waste into fission products might best be done with thermalized spallation neutrons and odd-odd target materials such as {sup 238}Np has been studied. During the 1993 LAMPF/PSR cycle, we measured the fission cross section of 1.3-day {sup 232}Pa and 2.1-day {sup 238}Np from 0.01 eV to 40 keV at the LANSCE facility, and have carried out a preliminary resonance analysis of the observed structure and of the thermal region, with a 1/v representation above a few eV. In the present study, we calculate the reaction rates of these two species and {sup 247}Cm in a 'resonance reactor', an accelerator-driven assembly whose slowing-down properties are well known. Our model is a 1.8 m{sup 3} block of lead with a helium-cooled tungsten target in the center, i.e., the Rensselaer Intense Neutron Source (RINS). We include the effects of adding moderator outside an idealized lead slowing-down assembly, giving resonance enhancement factors for {sup 232}Pa and {sup 238}Np, and present parameters for the accelerator required to drive such an assembly to accomplish actinide burnup of these species.

  1. Determining the americium transmutation rate and fission rate by post-irradiation examination within the scope of the ECRIX-H experiment

    NASA Astrophysics Data System (ADS)

    Lamontagne, J.; Pontillon, Y.; Esbelin, E.; Béjaoui, S.; Pasquet, B.; Bourdot, P.; Bonnerot, J. M.

    2013-09-01

    The ECRIX-H experiment aims to assess the feasibility of transmuting americium micro-dispersed in an inert magnesia matrix under a locally moderated neutron flux in the Phénix reactor. A first set of examinations demonstrated that pellet behaviour was satisfactory with moderate swelling at the end of the irradiation. Additional post-irradiation examinations needed to be conducted to confirm the high transmutation rate so as to definitively conclude on the success of the ECRIX-H experiment. This article presents and discusses the results of these new examinations. They confirm the satisfactory behaviour of the MgO matrix not only during the basic irradiation but also during post-irradiation thermal transients. These examinations also provide additional information on the behaviour of fission products both in the americium-based particles and in the MgO matrix. These results particularly validate the transmutation rate predicted by the calculation codes using several different analytical techniques. The fission rate is also determined. Moderate pellet swelling under irradiation (6.7 vol.%), while only 23% of the produced He and 4% of the fission gases were released from the fuel. No interaction between the pellets and the cladding. Formation of bubbles due to the precipitation of fission gases and He mainly in bubbles located inside the americium-based particles. These bubbles are the main cause of macroscopic swelling in the pellets. Well-crystallised structure of the MgO matrix which shows no amorphisation after irradiation despite the presence of fission products. The absence of any reaction of MgO with the americium-based phase, Formation of a PuO2-type crystalline phase from AmO1.62 particles following the Am transmutation process. A shielded electron probe micro-analyser (EPMA) 'CAMECA' Camebax equipped to collect and exploit the measurements using the 'SAMx' system. A Philips XL30 scanning electron microscope (SEM). Field acquisitions were performed thanks to

  2. Manifold-Splitting Regularization, Self-Linking Twisting, Writhing Numbers of Space-Time Ribbons and POLYAKOV’S Proof of Fermi-Bose Transmutations

    NASA Astrophysics Data System (ADS)

    Tze, Chia-Hsiung

    We present an alternative formulation of Polyakov’s regularization of Gauss’ integral formula for a single closed Feynman path. A key element in his proof of the D=3 fermi-bose transmutations induced by topological gauge fields, this regularization is linked here with the existence and properties of a nontrivial topological invariant for a closed space ribbon. This self-linking coefficient, an integer, is the sum of two differential characteristics of the ribbon, its twisting and writhing numbers. These invariants form the basis for a physical interpretation of our regularization. Their connection to Polyakov’s spinorization is discussed. We further generalize our construction to the self-linking, twisting and writhing of higher dimensional d=n (odd) submanifolds in D=(2n+1) space-time. Our comprehensive analysis intends to supplement Polyakov’s work as it identifies a natural path to its higher dimensional mathematical and physical generalizations. Combining the theorems of White on self-linking of manifolds and of Adams on nontrivial Hopf fibre bundles and the four composition-division algebras, we argue that besides Polyakov’s case where (d, D)=(1, 3) tied to complex numbers, the potentially interesting extensions are two chiral models with (d, D)=(3, 7) and (7, 15) uniquely linked to quaternions and octonions. In Memoriam Richard P. Feynman

  3. Experimental tectonophysics

    SciTech Connect

    Handin, J.; Logan, J.M.

    1981-07-01

    Because virtually all tectonophysical processes are marked by the overburden, or occur to slowly for adequate observation in anthropocentric time, or both, they must be studied in carefully controlled laboratory experiments that simulate the natural environment as realistically as is practicable. Extrapolations of laboratory data in space and time are invalid unless the experimental and natural phenomenologies are essentially the same. The size of conventional specimens is of the order of 10 cm, whereas the discontinuities (defects in a continuum) in real rock-masses are often much larger, of the order of 1 m or more. Furthermore, such discontinuities as macrofractures (joints) may well dominate the mechanical and fluid-transport properties in nature. Adequate sampling of rock-mass properties will probably always require in-situ testing, but testing machines much larger than any now available could provide useful data at least at intermediate scale.

  4. Experimental Tachyons

    NASA Astrophysics Data System (ADS)

    Soli, George

    2008-05-01

    In the physics of potential superluminal information transfer, causality is preserved by the experimental identification of the CMB (Cosmic Microwave Background) rest frame, as the preferred inertial frame in which potential superluminal information transfer is isotropic [Rembielinski] (http://arxiv.org/PScache/quant-ph/pdf/0010/0010026v2.pdf). Potential superluminal information transfer is engineered by tunneling through two successive barriers [Olkhovsky] (http://arxiv.org/PScache/quant-ph/pdf/0002/0002022v5.pdf). In our experiment we use two meter wavelength photons tunneling through two water-tank barriers, separated by an air-gap length [Soli] (http://www.siderealdilaton.com/). The data presented in this talk demonstrates that if the air-gap length is adjusted for subluminal information transfer, then the democracy of inertial frames is recovered, and no preferred frame is measured. The one-way subluminal tunneling group velocity of light is shown to be isotropic to accuracy below the CMB rest frame velocity. It has already been argued in the literature that Einstein's special relativity with tachyons predicts the existence of antimatter [Recami] (http://arxiv.org/PScache/arxiv/pdf/0709/0709.2453v1.pdf). We conjecture that the dilaton scalar particle is discovered by any sidereal data producible by this instrument.

  5. Corrosion by liquid lead and lead-bismuth: experimental results review and analysis

    SciTech Connect

    Zhang, Jinsuo

    2008-01-01

    Liquid metal technologies for liquid lead and lead-bismuth alloy are under wide investigation and development for advanced nuclear energy systems and waste transmutation systems. Material corrosion is one of the main issues studied a lot recently in the development of the liquid metal technology. This study reviews corrosion by liquid lead and lead bismuth, including the corrosion mechanisms, corrosion inhibitor and the formation of the protective oxide layer. The available experimental data are analyzed by using a corrosion model in which the oxidation and scale removal are coupled. Based on the model, long-term behaviors of steels in liquid lead and lead-bismuth are predictable. This report provides information for the selection of structural materials for typical nuclear reactor coolant systems when selecting liquid lead or lead bismuth as heat transfer media.

  6. International Nuclear Energy Research Initiative Development of Computational Models for Pyrochemical Electrorefiners of Nuclear Waste Transmutation Systems

    SciTech Connect

    M.F. Simpson; K.-R. Kim

    2010-12-01

    In support of closing the nuclear fuel cycle using non-aqueous separations technology, this project aims to develop computational models of electrorefiners based on fundamental chemical and physical processes. Spent driver fuel from Experimental Breeder Reactor-II (EBR-II) is currently being electrorefined in the Fuel Conditioning Facility (FCF) at Idaho National Laboratory (INL). And Korea Atomic Energy Research Institute (KAERI) is developing electrorefining technology for future application to spent fuel treatment and management in the Republic of Korea (ROK). Electrorefining is a critical component of pyroprocessing, a non-aqueous chemical process which separates spent fuel into four streams: (1) uranium metal, (2) U/TRU metal, (3) metallic high-level waste containing cladding hulls and noble metal fission products, and (4) ceramic high-level waste containing sodium and active metal fission products. Having rigorous yet flexible electrorefiner models will facilitate process optimization and assist in trouble-shooting as necessary. To attain such models, INL/UI has focused on approaches to develop a computationally-light and portable two-dimensional (2D) model, while KAERI/SNU has investigated approaches to develop a computationally intensive three-dimensional (3D) model for detailed and fine-tuned simulation.

  7. Analysis of neutron spectra and fluxes obtained with cold and thermal moderators at IBR-2 reactor: Experimental and computer-modeling studies

    NASA Astrophysics Data System (ADS)

    Kuklin, A. I.; Rogov, A. D.; Gorshkova, Yu. E.; Utrobin, P. K.; Kovalev, Yu. S.; Rogachev, A. V.; Ivankov, O. I.; Kutuzov, S. A.; Soloviov, D. V.; Gordeliy, V. I.

    2011-03-01

    The results of experimental and computer-modeling investigations of neutron spectra and fluxes obtained with cold and thermal moderators at the IBR-2 reactor (Joint Institute for Nuclear Research (JINR), Dubna) are presented. These studies are for the YuMO small-angle neutron scattering (SANS) spectrometer (IBR-2 beamline 4). The neutron spectra have been measured for two methane cold moderators for the standard configuration of the SANS instrument. The data from both moderators under different conditions of their operation are compared. The ratio of experimentally determined neutron fluxes of cold and thermal moderators is shown at different wavelengths. Monte Carlo simulations have been carried out to determine the spectra for cold-methane and thermal moderators. The results of calculations of the ratio of neutron fluxes of cold and thermal moderators at different wavelengths are demonstrated. In addition, the absorption of neutrons in the air gaps on the way from the moderator to the investigated sample is presented. SANS with the protein apoferritin was done with both cold methane and a thermal moderator and the data were compared. The prospects for the use of a cold moderator for a SANS spectrometer at IBR-2 are discussed. The advantages of using the YuMO spectrometer with a thermal moderator with respect to the tested cold moderator are shown.

  8. Review of Transmutation Fuel Studies

    SciTech Connect

    Jon Carmack; Kemal O. Pasamehmetoglu

    2008-01-01

    The technology demonstration element of the Global Nuclear Energy Partnership (GNEP) program is aimed at demonstrating the closure of the fuel cycle by destroying the transuranic (TRU) elements separated from spent nuclear fuel (SNF). Multiple recycle through fast reactors is used for burning the TRU initially separated from light-water reactor (LWR) spent nuclear fuel. For the initial technology demonstration, the preferred option to demonstrate the closed fuel cycle destruction of TRU materials is a sodium-cooled fast reactor (FR) used as burner reactor. The sodium-cooled fast reactor represents the most mature sodium reactor technology available today. This report provides a review of the current state of development of fuel systems relevant to the sodium-cooled fast reactor. This report also provides a review of research and development of TRU-metal alloy and TRU-oxide composition fuels. Experiments providing data supporting the understanding of minor actinide (MA)-bearing fuel systems are summarized and referenced.

  9. Heterogeneous Transmutation Sodium Fast Reactor

    SciTech Connect

    S. E. Bays

    2007-09-01

    The threshold-fission (fertile) nature of Am-241 is used to destroy this minor actinide by capitalizing upon neutron capture instead of fission within a sodium fast reactor. This neutron-capture and its subsequent decay chain leads to the breeding of even neutron number plutonium isotopes. A slightly moderated target design is proposed for breeding plutonium in an axial blanket located above the active “fast reactor” driver fuel region. A parametric study on the core height and fuel pin diameter-to-pitch ratio is used to explore the reactor and fuel cycle aspects of this design. This study resulted in both non-flattened and flattened core geometries. Both of these designs demonstrated a high capacity for removing americium from the fuel cycle. A reactivity coefficient analysis revealed that this heterogeneous design will have comparable safety aspects to a homogeneous reactor of comparable size. A mass balance analysis revealed that the heterogeneous design may reduce the number of fast reactors needed to close the current once-through light water reactor fuel cycle.

  10. Experimental Summary and Outlook

    SciTech Connect

    Peter Bosted

    2005-02-01

    A brief experimental overview of the workshop is given, with emphasis on polarized targets from the experimental equipment perspective, and kinematic coverage, precision, and newly investigated channels from the experimental results perspective.

  11. Experimental evidence of an incomplete thermalization of the energy in an x-ray microcalorimeter with a TaAu absorber.

    PubMed

    Perinati, E; Barbera, M; Varisco, S; Silver, E; Beeman, J; Pigot, C

    2008-05-01

    We have conducted an experimental test at our XACT facility using an x-ray microcalorimeter with TaAu absorber and neutron transmutation doped germanium thermal sensor. The test was aimed at measuring the percentage of energy effectively thermalized after absorption of x-ray photons in superconducting tantalum. Moreover, in general, possible formation of long living quasiparticles implies that by using a superconducting absorber, a fraction of the deposited energy could not be thermalized on the useful time scale of the thermal sensor. To investigate this scenario, we exploited an absorber made of gold, where no energy trapping is expected, with a small piece of superconducting tantalum attached on top. We obtained evidence that the thermalization of photons absorbed in tantalum is delayed by energy trapping from quasiparticles. We compare the experimental results with numerical simulations and derive a value for the intrinsic lifetime of quasiparticles. PMID:18513077

  12. Experimental and Quasi-Experimental Design.

    ERIC Educational Resources Information Center

    Cottrell, Edward B.

    With an emphasis on the problems of control of extraneous variables and threats to internal and external validity, the arrangement or design of experiments is discussed. The purpose of experimentation in an educational institution, and the principles governing true experimentation (randomization, replication, and control) are presented, as are…

  13. Definition of "experimental procedures".

    PubMed

    2009-11-01

    This Practice Committee Opinion provides a revised definition of "experimental procedures." This version replaces the document "Definition of Experimental" that was published most recently in November 2008. PMID:19836733

  14. Microexperiencia Educativa (Microeducational Experimentation).

    ERIC Educational Resources Information Center

    Burton Meis, Roberto

    1970-01-01

    Experimentation for educational reform in Argentina is limited to specifically designated schools which are to be in a permanent state of experimentation. This article presents the official statements designating the experimental schools and includes remarks covering administration, evaluation, and supervision. (VM)

  15. Experimentation in software engineering

    NASA Technical Reports Server (NTRS)

    Basili, V. R.; Selby, R. W.; Hutchens, D. H.

    1986-01-01

    Experimentation in software engineering supports the advancement of the field through an iterative learning process. In this paper, a framework for analyzing most of the experimental work performed in software engineering over the past several years is presented. A variety of experiments in the framework is described and their contribution to the software engineering discipline is discussed. Some useful recommendations for the application of the experimental process in software engineering are included.

  16. Questioning and Experimentation

    ERIC Educational Resources Information Center

    Mutanen, Arto

    2014-01-01

    The paper is a philosophical analysis of experimentation. The philosophical framework of the analysis is the interrogative model of inquiry developed by Hintikka. The basis of the model is explicit and well-formed logic of questions and answers. The framework allows us to formulate a flexible logic of experimentation. In particular, the formulated…

  17. 7. VIEW WEST, FERNOW EXPERIMENTAL FOREST WELL HOUSE, FERNOW EXPERIMENTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. VIEW WEST, FERNOW EXPERIMENTAL FOREST WELL HOUSE, FERNOW EXPERIMENTAL FOREST BUNKHOUSE, FERNOW EXPERIMENTAL FOREST GARAGE, AND FERNOW EXPERIMENTAL FOREST RESIDENCE. - Parsons Nursery, South side of U.S. Route 219, Parsons, Tucker County, WV

  18. The Experimental Hydrology Wiki

    NASA Astrophysics Data System (ADS)

    Blume, Theresa; van Meerveld, Ilja; Graeff, Thomas

    2013-04-01

    The "Experimental Hydrology Wiki" is a forum for hydrologists to learn about, recommend, question and discuss new and established, basic and advanced methods and equipment for hydrological research. As a database of "lessons learned" it does not only contain short descriptions of specific experimental equipment but also information on encountered errors and problems and recommendations on how to deal with them. This makes valuable personal field experience accessible to a wider audience. The Wiki allows experimentalists to share and find solutions for common problems and thus helps us in not making the same mistakes others have made before us. At the same time modellers can use this platform to find information on sources of error and uncertainty in the data they use for model validation and calibration. The general idea and layout of the Experimental Hydrology Wiki is presented here along with an invitation to all experimental hydrologists to contribute their knowledge and experiences! http://www.experimental- hydrology.net/

  19. An Atomistic Modeling Study of Alloying Element Impurity Element, and Transmutation Products on the cohesion of A Nickel E5 {l_brace}001{r_brace} Twist Grain Boundary

    SciTech Connect

    G.A. Young Jr.; R. Najafabadi; W. Strohmayer; D.G. Baldrey; B. Hamm; J. Harris; J. Sticht; E. Wimmer

    2003-06-16

    Atomistic modeling methods were employed to investigate the effects of impurity elements on the metallurgy, irradiation embrittlement, and environmentally assisted cracking of nickel-base alloys exposed to nuclear environments. Calculations were performed via ab initio atomistic modeling methods to ensure the accuracy and reliability of the results. A Griffith-type fracture criterion was used to quantitatively assess the effect of elements or element pairs on the grain boundary cohesive strength. In order of most embrittling to most strengthening, the elements are ranked as: He, Li, S, H, C, Zr, P, Fe, Mn, Nb, Cr, and B. Helium is strongly embrittling (-2.04 eV/atom lowering of the Griffith energy), phosphorus has little effect on the grain boundary (0.1 eV/atom), and boron offers appreciable strengthening (1.03 eV/atom increase in the Griffith energy). Calculations for pairs of elements (H-Li, H-B, H-C, H-P, and H-S) show little interaction on the grain boundary cohesive energy, so that for the conditions studied, linear superposition of elemental effects is a good approximation. These calculations help explain metallurgical effects (e.g. why boron can strengthen grain boundaries), irradiation embrittlement (e.g. how boron transmutation results in grain boundary embrittlement), as well as how grain boundary impurity elements can affect environmentally assisted cracking (i.e. low temperature crack propagation and stress corrosion cracking) of nickel-base alloys.

  20. Magnetohydrodynamic generator experimental studies

    NASA Technical Reports Server (NTRS)

    Pierson, E. S.

    1972-01-01

    The results for an experimental study of a one wavelength MHD induction generator operating on a liquid flow are presented. First the design philosophy and the experimental generator design are summarized, including a description of the flow loop and instrumentation. Next a Fourier series method of treating the fact that the magnetic flux density produced by the stator is not a pure traveling sinusoid is described and some results summarized. This approach appears to be of interest after revisions are made, but the initial results are not accurate. Finally, some of the experimental data is summarized for various methods of excitation.

  1. Experimental Semiotics: A Review

    PubMed Central

    Galantucci, Bruno; Garrod, Simon

    2010-01-01

    In the last few years a new line of research has appeared in the literature. This line of research, which may be referred to as experimental semiotics (ES; Galantucci, 2009; Galantucci and Garrod, 2010), focuses on the experimental investigation of novel forms of human communication. In this review we will (a) situate ES in its conceptual context, (b) illustrate the main varieties of studies thus far conducted by experimental semioticians, (c) illustrate three main themes of investigation which have emerged within this line of research, and (d) consider implications of this work for cognitive neuroscience. PMID:21369364

  2. Experimental study of the electric dipole strength in the even Mo nuclei and its deformation dependence

    NASA Astrophysics Data System (ADS)

    Erhard, M.; Junghans, A. R.; Nair, C.; Schwengner, R.; Beyer, R.; Klug, J.; Kosev, K.; Wagner, A.; Grosse, E.

    2010-03-01

    Two methods based on bremsstrahlung were applied to the stable even Mo isotopes for the experimental determination of the photon strength function covering the high excitation energy range above 4 MeV with its increasing level density. Photon scattering was used up to the neutron separation energies Sn and data up to the maximum of the isovector giant resonance (GDR) were obtained by photoactivation. After a proper correction for multistep processes the observed quasicontinuous spectra of scattered photons show a remarkably good match to the photon strengths derived from nuclear photoeffect data obtained previously by neutron detection and corrected in absolute scale by using the new activation results. The combined data form an excellent basis to derive a shape dependence of the E1 strength in the even Mo isotopes with increasing deviation from the N=50 neutron shell (i.e., with the impact of quadrupole deformation and triaxiality). The wide energy coverage of the data allows for a stringent assessment of the dipole sum rule and a test of a novel parametrization developed previously which is based on it. This parametrization for the electric dipole strength function in nuclei with A>80 deviates significantly from prescriptions generally used previously. In astrophysical network calculations it may help to quantify the role the p-process plays in cosmic nucleosynthesis. It also has impact on the accurate analysis of neutron capture data of importance for future nuclear energy systems and waste transmutation.

  3. Designing an Experimental "Accident"

    ERIC Educational Resources Information Center

    Picker, Lester

    1974-01-01

    Describes an experimental "accident" that resulted in much student learning, seeks help in the identification of nematodes, and suggests biology teachers introduce similar accidents into their teaching to stimulate student interest. (PEB)

  4. Nuclear test experimental science

    SciTech Connect

    Struble, G.L.; Middleton, C.; Bucciarelli, G.; Carter, J.; Cherniak, J.; Donohue, M.L.; Kirvel, R.D.; MacGregor, P.; Reid, S.

    1989-01-01

    This report discusses research being conducted at Lawrence Livermore Laboratory under the following topics: prompt diagnostics; experimental modeling, design, and analysis; detector development; streak-camera data systems; weapons supporting research.

  5. Experimental scattershot boson sampling

    PubMed Central

    Bentivegna, Marco; Spagnolo, Nicolò; Vitelli, Chiara; Flamini, Fulvio; Viggianiello, Niko; Latmiral, Ludovico; Mataloni, Paolo; Brod, Daniel J.; Galvão, Ernesto F.; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto; Sciarrino, Fabio

    2015-01-01

    Boson sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialized quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, scattershot boson sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric down-conversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. We report the first scattershot boson sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We use recently proposed statistical tools to analyze our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy. PMID:26601164

  6. Experimental probes of axions

    SciTech Connect

    Chou, Aaron S.; /Fermilab

    2009-10-01

    Experimental searches for axions or axion-like particles rely on semiclassical phenomena resulting from the postulated coupling of the axion to two photons. Sensitive probes of the extremely small coupling constant can be made by exploiting familiar, coherent electromagnetic laboratory techniques, including resonant enhancement of transitions using microwave and optical cavities, Bragg scattering, and coherent photon-axion oscillations. The axion beam may either be astrophysical in origin as in the case of dark matter axion searches and solar axion searches, or created in the laboratory from laser interactions with magnetic fields. This note is meant to be a sampling of recent experimental results.

  7. SPHINX experimenters information package

    SciTech Connect

    Zarick, T.A.

    1996-08-01

    This information package was prepared for both new and experienced users of the SPHINX (Short Pulse High Intensity Nanosecond X-radiator) flash X-Ray facility. It was compiled to help facilitate experiment design and preparation for both the experimenter(s) and the SPHINX operational staff. The major areas covered include: Recording Systems Capabilities,Recording System Cable Plant, Physical Dimensions of SPHINX and the SPHINX Test cell, SPHINX Operating Parameters and Modes, Dose Rate Map, Experiment Safety Approval Form, and a Feedback Questionnaire. This package will be updated as the SPHINX facilities and capabilities are enhanced.

  8. Questioning and Experimentation

    NASA Astrophysics Data System (ADS)

    Mutanen, Arto

    2014-08-01

    The paper is a philosophical analysis of experimentation. The philosophical framework of the analysis is the interrogative model of inquiry developed by Hintikka. The basis of the model is explicit and well-formed logic of questions and answers. The framework allows us to formulate a flexible logic of experimentation. In particular, the formulated model can be interpreted realistically. Moreover, the model demonstrates an explicit logic of knowledge acquisition. So, the natural extension of the model is to apply it to an analysis of the learning process.

  9. The Irradiation Facility at the IBR-2M Reactor in Dubna

    NASA Astrophysics Data System (ADS)

    Bulavin, M.; Cheplakov, A.; Kulikov, S.; Kukhtin, V.; Shabalin, E.; Verhoglyadov, A.

    2014-06-01

    After renovation neutron pulsed reactor was successfully put into operation. In view of HL-LHC development, the irradiation facility at the IBR-2m, previously used for the ATLAS Liquid Argon calorimeters electronics and materials certification, has been upgraded to permit accumulation in the warm temperature conditions of the fast neutrons fluences up to k*1017 n/cm2 per one standard reactor operation cycle - 11 days. The first test of materials for ATLAS was conducted.

  10. Communicating Uncertain Experimental Evidence

    ERIC Educational Resources Information Center

    Davis, Alexander L.; Fischhoff, Baruch

    2014-01-01

    Four experiments examined when laypeople attribute unexpected experimental outcomes to error, in foresight and in hindsight, along with their judgments of whether the data should be published. Participants read vignettes describing hypothetical experiments, along with the result of the initial observation, considered as either a possibility…

  11. EXPERIMENTAL ANIMAL MAINTENANCE

    DOEpatents

    Finkel, M.P.

    1962-01-22

    A method of housing experimental animals such as mice in individual tube- like plastic enclosures is described. Contrary to experience, when this was tried with metal the mice did not become panicky. Group housing, with its attendant difficulties, may thus be dispensed with. (AEC)

  12. Experimental fluvial geomorphology

    SciTech Connect

    Schumm, S.A.; Mosley, M.P.; Weaver, W.

    1987-01-01

    The authors bring together the results of several years of experimental work in drainage basin evolution, hydrology, river-channel morphology, and sedimentology. These investigations are related to real-world applications, particularly geological exploration and mapping. This text shows how awareness of natural phenomena can improve management of the natural environment, such as the control of rivers and eroding gullies.

  13. Administrative Aspects of Human Experimentation.

    ERIC Educational Resources Information Center

    Irvine, George W.

    1992-01-01

    The following administrative aspects of scientific experimentation with human subjects are discussed: the definition of human experimentation; the distinction between experimentation and treatment; investigator responsibility; documentation; the elements and principles of informed consent; and the administrator's role in establishing and…

  14. Teaching experimental design.

    PubMed

    Fry, Derek J

    2014-01-01

    Awareness of poor design and published concerns over study quality stimulated the development of courses on experimental design intended to improve matters. This article describes some of the thinking behind these courses and how the topics can be presented in a variety of formats. The premises are that education in experimental design should be undertaken with an awareness of educational principles, of how adults learn, and of the particular topics in the subject that need emphasis. For those using laboratory animals, it should include ethical considerations, particularly severity issues, and accommodate learners not confident with mathematics. Basic principles, explanation of fully randomized, randomized block, and factorial designs, and discussion of how to size an experiment form the minimum set of topics. A problem-solving approach can help develop the skills of deciding what are correct experimental units and suitable controls in different experimental scenarios, identifying when an experiment has not been properly randomized or blinded, and selecting the most efficient design for particular experimental situations. Content, pace, and presentation should suit the audience and time available, and variety both within a presentation and in ways of interacting with those being taught is likely to be effective. Details are given of a three-day course based on these ideas, which has been rated informative, educational, and enjoyable, and can form a postgraduate module. It has oral presentations reinforced by group exercises and discussions based on realistic problems, and computer exercises which include some analysis. Other case studies consider a half-day format and a module for animal technicians. PMID:25541547

  15. Geoengineering as Collective Experimentation.

    PubMed

    Stilgoe, Jack

    2016-06-01

    Geoengineering is defined as the 'deliberate and large-scale intervention in the Earth's climatic system with the aim of reducing global warming'. The technological proposals for doing this are highly speculative. Research is at an early stage, but there is a strong consensus that technologies would, if realisable, have profound and surprising ramifications. Geoengineering would seem to be an archetype of technology as social experiment, blurring lines that separate research from deployment and scientific knowledge from technological artefacts. Looking into the experimental systems of geoengineering, we can see the negotiation of what is known and unknown. The paper argues that, in renegotiating such systems, we can approach a new mode of governance-collective experimentation. This has important ramifications not just for how we imagine future geoengineering technologies, but also for how we govern geoengineering experiments currently under discussion. PMID:25862639

  16. Experimental Neutrino Physics

    ScienceCinema

    Walter, Chris [Duke University, Durham, North Carolina, United States

    2010-01-08

    In this talk, I will review how a set of experiments in the last decade has given us our current understanding of neutrino properties.  I will show how experiments in the last year or two have clarified this picture, and will discuss how new experiments about to start will address remaining questions.  I will particularly emphasize the relationship between various experimental techniques.

  17. Blois V: Experimental summary

    SciTech Connect

    Albrow, M.G.

    1993-09-01

    The author gives a summary talk of the best experimental data given at the Vth Blois Workshop on Elastic and Diffractive Scattering. He addresses the following eight areas in his talk: total and elastic cross sections; single diffractive excitation; electron-proton scattering; di-jets and rapidity gaps; areas of future study; spins and asymmetries; high-transverse momentum and masses at the Tevatron; and disoriented chiral condensates and cosmic radiation.

  18. MSFC Skylab experimenter's reference

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The methods and techniques for experiment development and integration that evolved during the Skylab Program are described to facilitate transferring this experience to experimenters in future manned space programs. Management responsibilities and the sequential process of experiment evolution from initial concept through definition, development, integration, operation and postflight analysis are outlined in the main text and amplified, as appropriate, in appendixes. Emphasis is placed on specific lessons learned on Skylab that are worthy of consideration by future programs.

  19. Structural femtochemistry: experimental methodology.

    PubMed Central

    Williamson, J C; Zewail, A H

    1991-01-01

    The experimental methodology for structural femtochemistry of reactions is considered. With the extension of femtosecond transition-state spectroscopy to the diffraction regime, it is possible to obtain in a general way the trajectories of chemical reactions (change of internuclear separations with time) on the femtosecond time scale. This method, considered here for simple alkali halide dissociation, promises many applications to more complex reactions and to conformational changes. Alignment on the time scale of the experiments is also discussed. Images PMID:11607189

  20. SAA drift: Experimental results

    NASA Astrophysics Data System (ADS)

    Grigoryan, O. R.; Romashova, V. V.; Petrov, A. N.

    According to the paleomagnetic analysis there are variations of Earth’s magnetic field connected with magnetic moment changing. These variations affect on the South Atlantic Anomaly (SAA) location. Indeed different observations approved the existence of the SAA westward drift rate (0.1 1.0 deg/year) and northward drift rate (approximately 0.1 deg/year). In this work, we present the analysis of experimental results obtained in Scobeltsyn Institute of Nuclear Physics, Moscow State University (SINP MSU) onboard different Earth’s artificial satellites (1972 2003). The fluxes of protons with energy >50 MeV, gamma quanta with energy >500 keV and neutrons with energy 0.1 1.0 MeV in the SAA region have been analyzed. The mentioned above experimental data were obtained onboard the orbital stations Salut-6 (1979), MIR (1991, 1998) and ISS (2003) by the similar experimental equipment. The comparison of the data obtained during these two decades of investigations confirms the fact that the SAA drifts westward. Moreover the analysis of fluxes of electrons with energy about hundreds keV (Cosmos-484 (1972) and Active (Interkosmos-24, 1991) satellites) verified not only the SAA westward drift but northward drift also.

  1. Primary retention following nuclear recoil in β-decay: Proposed synthesis of a metastable rare gas oxide ((38)ArO4) from ((38)ClO4(-)) and the evolution of chemical bonding over the nuclear transmutation reaction path.

    PubMed

    Timm, Matthew J; Matta, Chérif F

    2014-12-01

    Argon tetroxide (ArO4) is the last member of the N=50 e(-) isoelectronic and isosteric series of ions: SiO4(4-), PO4(3-), SO4(2-), and ClO4(-). A high level computational study demonstrated that while ArO4 is kinetically stable it has a considerable positive enthalpy of formation (of ~298kcal/mol) (Lindh et al., 1999. J. Phys. Chem. A 103, pp. 8295-8302) confirming earlier predictions by Pyykkö (1990. Phys. Scr. 33, pp. 52-53). ArO4 can be expected to be difficult to synthesize by traditional chemistry due to its metastability and has not yet been synthesized at the time of writing. A computational investigation of the changes in the chemical bonding of chlorate (ClO4(-)) when the central chlorine atom undergoes a nuclear transmutation from the unstable artificial chlorine isotope (38)Cl to the stable rare argon isotope (38)Ar through β-decay, hence potentially leading to the formation of ArO4, is reported. A mathematical model is presented that allows for the prediction of yields following the recoil of a nucleus upon ejecting a β-electron. It is demonstrated that below a critical angle between the ejected β-electron and that of the accompanying antineutrino their respective linear momentums can cancel to such an extent as imparting a recoil to the daughter atom insufficient for breaking the Ar-O bond. As a result, a primary retention yield of ~1% of ArO4 is predicted following the nuclear disintegration. The study is conducted at the quadratic configuration interaction with single and double excitations [QCISD/6-311+G(3df)] level of theory followed by an analysis of the electron density by the quantum theory of atoms in molecules (QTAIM). Crossed potential energy surfaces (PES) were used to construct a PES from the metastable ArO4 ground singlet state to the Ar-O bond dissociation product ArO3+O((3)P) from which the predicted barrier to dissociation is ca. 22kcal/mol and the exothermic reaction energy is ca. 28kcal/mol [(U)MP2/6-311+G(d)]. PMID:25222874

  2. Electrodeless Experimental Thruster

    SciTech Connect

    Brainerd, Jerome J.; Reisz, Al

    2009-03-16

    An electrodeless experimental electric thruster has been built and tested at the NASA Marshall Space Flight Center (MSFC). The plasma is formed by Electron-Cyclotron Resonance (ECR) absorption of RF waves (microwaves). The RF source operates in the 1 to 2 kW range. The plasma is overdense and is confined radially by an applied axial dc magnetic field. The field is shaped by a strong magnetic mirror on the upstream end and a magnetic nozzle on the downstream end. Argon is used as the propellant. The velocity profile in the exhaust plume has been measured with Laser Induced Fluorescence (LIF). An unusual bimodal velocity profile has been measured.

  3. Electric propulsion: Experimental research

    NASA Technical Reports Server (NTRS)

    Ruyten, W. M.; Friedly, V. J.; Keefer, D.

    1992-01-01

    This paper describes experimental electric propulsion research which was carried out at the University of Tennessee Space Institute with support from the Center for Space Transportation and Applied Research. Specifically, a multiplexed laser induced fluorescence (LIF) technique for obtaining vector velocities, Doppler temperatures, and relative number densities in the exhaust plumes from electric propulsion devices is described, and results are presented that were obtained on a low power argon arcjet. Also, preliminary Langmuir probe measurements on an ion source are described, and an update on the vacuum facility is presented.

  4. Electric Propulsion: Experimental Research

    NASA Technical Reports Server (NTRS)

    Ruyten, W. M.; Friedly, V. J.; Keefer, D.

    1995-01-01

    This paper describes experimental electric propulsion research which was carried out at the University of Tennessee Space Institute with support from the Center for Space Transportation and Applied Research. Specifically, a multiplexed LIF technique for obtaining vector velocities, Doppler temperatures, and relative number densities in the exhaust plumes form electric propulsion devices is described, and results are presented that were obtained on a low power argon arcjet. Also, preliminary Langmuir probe measurements on an ion source are described, and an update on the vacuum facility is presented.

  5. EXPERIMENTAL ANIMAL WATERING DEVICE

    DOEpatents

    Finkel, M.P.

    1964-04-01

    A device for watering experimental animals confined in a battery of individual plastic enclosures is described. It consists of a rectangular plastic enclosure having a plurality of fluid-tight compartments, each with a drinking hole near the bottom and a filling hole on the top. The enclosure is immersed in water until filled, its drinking holes sealed with a strip of tape, and it is then placed in the battery. The tape sealing prevents the flow of water from the device, but permits animals to drink by licking the drinking holes. (AEC)

  6. Experimental turbine VT-400

    NASA Astrophysics Data System (ADS)

    Zitek, Pavel; Milčák, Petr; Noga, Tomáš

    2016-03-01

    The experimental air turbine VT400 is located in hall laboratories of the Department of Power System Engineering. It is a single-stage air turbine located in the suction of the compressor. It is able to solve various problems concerning the construction solution of turbine stages. The content of the article will deal mainly with the description of measurements on this turbine. The up-to-now research on this test rig will be briefly mentioned, too, as well as the description of the ongoing reconstruction.

  7. [Animal experimentation in Israel].

    PubMed

    Epstein, Yoram; Leshem, Micah

    2002-04-01

    In 1994 the Israeli parliament (Knesset) amended the Cruelty to Animals Act to regulate the use of experimental animals. Accordingly, animal experiments can only be carried out for the purposes of promoting health and medical science, reducing suffering, advancing scientific research, testing or production of materials and products (excluding cosmetics and cleaning products) and education. Animal experiments are only permitted if alternative methods are not possible. The National Board for Animal Experimentation was established to implement the law. Its members are drawn from government ministries, representatives of doctors, veterinarians, and industry organizations, animal rights groups, and academia. In order to carry out an animal experiment, the institution, researchers involved, and the specific experiment, all require approval by the Board. To date the Board has approved some 35 institutions, about half are public institutions (universities, hospitals and colleges) and the rest industrial firms in biotechnology and pharmaceutics. In 2000, 250,000 animals were used in research, 85% were rodents, 11% fowls, 1,000 other farm animals, 350 dogs and cats, and 39 monkeys. Academic institutions used 74% of the animals and industry the remainder. We also present summarized data on the use of animals in research in other countries. PMID:12017891

  8. Experimentation in machine discovery

    NASA Technical Reports Server (NTRS)

    Kulkarni, Deepak; Simon, Herbert A.

    1990-01-01

    KEKADA, a system that is capable of carrying out a complex series of experiments on problems from the history of science, is described. The system incorporates a set of experimentation strategies that were extracted from the traces of the scientists' behavior. It focuses on surprises to constrain its search, and uses its strategies to generate hypotheses and to carry out experiments. Some strategies are domain independent, whereas others incorporate knowledge of a specific domain. The domain independent strategies include magnification, determining scope, divide and conquer, factor analysis, and relating different anomalous phenomena. KEKADA represents an experiment as a set of independent and dependent entities, with apparatus variables and a goal. It represents a theory either as a sequence of processes or as abstract hypotheses. KEKADA's response is described to a particular problem in biochemistry. On this and other problems, the system is capable of carrying out a complex series of experiments to refine domain theories. Analysis of the system and its behavior on a number of different problems has established its generality, but it has also revealed the reasons why the system would not be a good experimental scientist.

  9. Experimental myocardial infarction

    PubMed Central

    Kumar, Raj; Joison, Julio; Gilmour, David P.; Molokhia, Farouk A.; Pegg, C. A. S.; Hood, William B.

    1971-01-01

    The hemodynamic effects of tachycardia induced by atrial pacing were investigated in left ventricular failure of acute and healing experimental myocardial infarction in 20 intact, conscious dogs. Myocardial infarction was produced by gradual inflation of a balloon cuff device implanted around the left anterior descending coronary artery 10-15 days prior to the study. 1 hr after acute myocardial infarction, atrial pacing at a rate of 180 beats/min decreased left ventricular end-diastolic pressure from 19 to 8 mm Hg and left atrial pressure from 17 to 12 mm Hg, without change in cardiac output. In the healing phase of myocardial infarction 1 wk later, atrial pacing decreased left ventricular end-diastolic pressure from 17 to 9 mm Hg and increased the cardiac output by 37%. This was accompanied by evidence of peripheral vasodilation. In two dogs with healing anterior wall myocardial infarction, left ventricular failure was enhanced by partial occlusion of the circumflex coronary artery. Both the dogs developed pulmonary edema. Pacing improved left ventricular performance and relieved pulmonary edema in both animals. In six animals propranolol was given after acute infarction, and left ventricular function deteriorated further. However the pacing-induced augmentation of cardiac function was unaltered and, hence, is not mediated by sympathetics. The results show that the spontaneous heart rate in left ventricular failure of experimental canine myocardial infarction may be less than optimal and that maximal cardiac function may be achieved at higher heart rates. Images PMID:4395910

  10. Experimental immunogenic rubeosis iridis.

    PubMed

    Shabo, A L; Maxwell, D S; Shintaku, P; Kreiger, A E; Straatsma, B R

    1977-04-01

    We have developed a primate model of rubeosis iridis in monkeys systemically sensitized to crystalline beef insulin. After intravitreal insulin injection, the dose-related immunogenic inflammation includes cells, flare, fibrin, and blood in the anterior chamber. With more severe inflammation, posterior synechiae, iris bombé, and cataracts occur. Of particular importance, new blood vessels develop within the stroma and on the anterior surface of the iris. Following injection of small amounts of insulin, the anterior surface vessels may regress over time, and the iris regains its normal appearance and coloration. However, the new stromal vessels persist and are cuffed by inflammatory cells including plasma cells. After injection of large amounts of insulin, more extensive structural alterations develop as noted above in conjunction with persistent iris anterior surface and stromal neovascularization. The relationship of rubeosis iridis to clinical inflammatory syndromes and to previous laboratory studies is discussed. Stromal neovascularization was a consistent finding in this experimental model even when anterior surface vessels regressed. On the basis of these experimental data and a review of publications describing human pathology, we believe that a broadening of the classic definition of rubeosis iridis is waranted to include a recognition of the stromal component of the clinical and pathologic findings. PMID:403154

  11. Experimental melioidosis in hens.

    PubMed

    Vesselinova, A; Najdenski, H; Nikolova, S; Kussovski, V

    1996-08-01

    Experimental intramuscular infection of hens with Pseudomonas pseudomallei, strain 2796 (1 x 10(9) CFU from a 24-h culture) was reproduced. Clinical, paraclinical and pathomorphological findings were followed from 1 to 30 days after challenge. Haemagglutinin titre, bacterial dissemination in the viscera, number of leucocytes, alveolar (aMa) and peritoneal (pMa) macrophages and their phagocytic activity in vitro were studied. During the course of infection a leucocytosis as well as an increased haemagglutinin titre (1:256) were established. The number of bacteria per gram tissue in the spleen and liver was highest at 1 day post-infection (p.i.). Melioidose bacteria from egg yolk were isolated at 15 and 30 days p.i. Leucocyte and pMa phagocytic activity was maximal at 3 days p.i. unlike the activity of aMa which increased gradually until the end of the study. Inflammatory-necrotic changes were found in the viscera and brain at 3 and 15 days p.i. The investigation of experimental melioidosis infection in hens showed that they are susceptible to P. pseudomallei and this disease takes a generalized subacute course. PMID:8794700

  12. On modelling nuclear reactions in meteorites

    NASA Technical Reports Server (NTRS)

    Ustinova, G. K.; Lavrukhina, A. K.

    1993-01-01

    An original method of experimental modeling depth distribution of radionuclides in sphere thick targets irradiated by protons in 4(pi)-geometry on JINR (Dubna) synchrocyclotron is described. Some results are presented.

  13. Experimental Quantum Coin Tossing

    NASA Astrophysics Data System (ADS)

    Molina-Terriza, G.; Vaziri, A.; Ursin, R.; Zeilinger, A.

    2005-01-01

    In this Letter we present the first implementation of a quantum coin-tossing protocol. This protocol belongs to a class of “two-party” cryptographic problems, where the communication partners distrust each other. As with a number of such two-party protocols, the best implementation of the quantum coin tossing requires qutrits, resulting in a higher security than using qubits. In this way, we have also performed the first complete quantum communication protocol with qutrits. In our experiment the two partners succeeded to remotely toss a row of coins using photons entangled in the orbital angular momentum. We also show the experimental bounds of a possible cheater and the ways of detecting him.

  14. Experimental Quantum Error Detection

    PubMed Central

    Jin, Xian-Min; Yi, Zhen-Huan; Yang, Bin; Zhou, Fei; Yang, Tao; Peng, Cheng-Zhi

    2012-01-01

    Faithful transmission of quantum information is a crucial ingredient in quantum communication networks. To overcome the unavoidable decoherence in a noisy channel, to date, many efforts have been made to transmit one state by consuming large numbers of time-synchronized ancilla states. However, such huge demands of quantum resources are hard to meet with current technology and this restricts practical applications. Here we experimentally demonstrate quantum error detection, an economical approach to reliably protecting a qubit against bit-flip errors. Arbitrary unknown polarization states of single photons and entangled photons are converted into time bins deterministically via a modified Franson interferometer. Noise arising in both 10 m and 0.8 km fiber, which induces associated errors on the reference frame of time bins, is filtered when photons are detected. The demonstrated resource efficiency and state independence make this protocol a promising candidate for implementing a real-world quantum communication network. PMID:22953047

  15. Planetary impact experimentation

    NASA Technical Reports Server (NTRS)

    Cintala, Mark J.; Schultz, Peter H.; Hoerz, Friedrich

    1987-01-01

    An understanding of impact processes in low- and microgravity environments would be advanced significantly by the construction and use of an impact facility on the Space Station. It is proposed that initial studies begin as soon as possible in ground-based impact laboratories, on the NASA KC-135 Reduced-Gravity Aircraft, and in existing drop towers. The resulting experience and information base could then be applied toward an experiment package designed for use on Shuttle orbiters to support pilot studies in orbital environments. These experiments, as well as the first efforts made on the IOC Space Station, should involve the impact of various free-floating targets; such studies would yield a substantial scientific return while providing valuable experience and engineering information for use in refining the design of the dedicated Space Station Impact Facility. The dedicated facility should be designed to support impact experimentation, including but not limited to cratering, asteroid and ring-particle dynamics, and accretional processes.

  16. Experimental evolution gone wild.

    PubMed

    Scheinin, M; Riebesell, U; Rynearson, T A; Lohbeck, K T; Collins, S

    2015-05-01

    Because of their large population sizes and rapid cell division rates, marine microbes have, or can generate, ample variation to fuel evolution over a few weeks or months, and subsequently have the potential to evolve in response to global change. Here we measure evolution in the marine diatom Skeletonema marinoi evolved in a natural plankton community in CO2-enriched mesocosms deployed in situ. Mesocosm enclosures are typically used to study how the species composition and biogeochemistry of marine communities respond to environmental shifts, but have not been used for experimental evolution to date. Using this approach, we detect a large evolutionary response to CO2 enrichment in a focal marine diatom, where population growth rate increased by 1.3-fold in high CO2-evolved lineages. This study opens an exciting new possibility of carrying out in situ evolution experiments to understand how marine microbial communities evolve in response to environmental change. PMID:25833241

  17. Characterization of experimental dynamos

    NASA Astrophysics Data System (ADS)

    Peffley, Nicholas L.; Goumilevski, Alexei G.; Cawthrone, A. B.; Lathrop, Daniel P.

    2000-07-01

    Laboratory models of geophysical magnetic field production require new experi-mental characterization methods. Self-generating liquid metal magnetic dynamos are explored using two new experiments. Kinematic dynamo studies lead us to charac-terize the magnetic field dynamics in terms of eigenvalues and eigenfrequencies of the induction equation. Observing the decay of magnetic field pulses indicates the real part of the leading eigenvalue of the induction equation, while a chirp magnetic field diagnoses the imaginary part of the eigenvalue. Finally, a single-frequency applied magnetic field characterizes the structure of the velocity field. These measurements provide a new means to characterize and measure the approach to self-generation. We present data from numerical simulations and laboratory experiments using these techniques.

  18. Experimental evolution gone wild

    PubMed Central

    Scheinin, M.; Riebesell, U.; Rynearson, T. A.; Lohbeck, K. T.; Collins, S.

    2015-01-01

    Because of their large population sizes and rapid cell division rates, marine microbes have, or can generate, ample variation to fuel evolution over a few weeks or months, and subsequently have the potential to evolve in response to global change. Here we measure evolution in the marine diatom Skeletonema marinoi evolved in a natural plankton community in CO2-enriched mesocosms deployed in situ. Mesocosm enclosures are typically used to study how the species composition and biogeochemistry of marine communities respond to environmental shifts, but have not been used for experimental evolution to date. Using this approach, we detect a large evolutionary response to CO2 enrichment in a focal marine diatom, where population growth rate increased by 1.3-fold in high CO2-evolved lineages. This study opens an exciting new possibility of carrying out in situ evolution experiments to understand how marine microbial communities evolve in response to environmental change. PMID:25833241

  19. Experimental traumatic brain injury

    PubMed Central

    2010-01-01

    Traumatic brain injury, a leading cause of death and disability, is a result of an outside force causing mechanical disruption of brain tissue and delayed pathogenic events which collectively exacerbate the injury. These pathogenic injury processes are poorly understood and accordingly no effective neuroprotective treatment is available so far. Experimental models are essential for further clarification of the highly complex pathology of traumatic brain injury towards the development of novel treatments. Among the rodent models of traumatic brain injury the most commonly used are the weight-drop, the fluid percussion, and the cortical contusion injury models. As the entire spectrum of events that might occur in traumatic brain injury cannot be covered by one single rodent model, the design and choice of a specific model represents a major challenge for neuroscientists. This review summarizes and evaluates the strengths and weaknesses of the currently available rodent models for traumatic brain injury. PMID:20707892

  20. Experimental study of spontaneous release of accumulated energy in irradiated ices

    NASA Astrophysics Data System (ADS)

    Shabalin, E.; Kulagin, E.; Kulikov, S.; Melikhov, V.

    2003-06-01

    A phenomenon of spontaneous release of energy accumulated in some hydrogenous materials under fast neutron irradiation at low temperature was studied at a cryogenic irradiation facility of the IBR-2 reactor in Dubna for the purpose of cold neutron moderator development. Spontaneous release of energy occurred in water ice after 5-11 h of fast neutron irradiation at temperature <34 K and at absorbed dose rate 0.4 MGy/h. In contrast with previous data, no spontaneous burp was observed in solid methane.

  1. Experimenter bias and subliminal perception

    ERIC Educational Resources Information Center

    Barber, Paul J.; Rushton, J. Philippe

    1975-01-01

    It has been suggested that subliminal perception phenomena may be in part due to experimenter bias effects. Two studies that obtained positive evidence of subliminal perception were therefore replicated with experimenters tested under blind and not blind conditions. (Editor)

  2. Transmutation Fuel Performance Code Thermal Model Verification

    SciTech Connect

    Gregory K. Miller; Pavel G. Medvedev

    2007-09-01

    FRAPCON fuel performance code is being modified to be able to model performance of the nuclear fuels of interest to the Global Nuclear Energy Partnership (GNEP). The present report documents the effort for verification of the FRAPCON thermal model. It was found that, with minor modifications, FRAPCON thermal model temperature calculation agrees with that of the commercial software ABAQUS (Version 6.4-4). This report outlines the methodology of the verification, code input, and calculation results.

  3. Actinide transmutation in a thermal reactor

    SciTech Connect

    Facchini, A.; Sanjust, V.

    1993-12-31

    The long term radiotoxicity of nuclear wastes may be substantially reduced by long irradiation in thermal reactors. Preliminary calculations showed that appreciable quantities of the minor actinides and long lived fission products may be recycled in a power PWR, and that, a few centuries after 20--30 years of irradiation, they reach radiotoxicity levels comparable to those of the uranium quantity required to make the corresponding fuel amount. The purpose of the present work is to investigate the conceptual possibility of reducing the level of the long term radiotoxicity, due to Minor Actinides and Long-Lived Fission Products (MA/LLFP) produced in UO{sub 2} fuel, by long irradiation of them in a power PWR. More precisely the authors pursued the objective of determining what fraction of the MA/LLFP mixture produced in a 1,000 MWe PWR during its whole life, may be burned in a similar power reactor. A waste burning efficiency has been considered satisfactory if the long term radiotoxicity of the MA/LLFP contained in a given quantity of spent fuel reaches, a few centuries after its irradiation, the level corresponding to that of the amount of natural uranium required to produce the same quantity of fresh fuel. This waiting time is in fact necessary in any case for cooling the other fission products to a sufficiently low radioactivity level and is a time span not unreasonable when considering man-made barriers against the radionuclide diffusion into the biosphere.

  4. MYRRHA, a Pb-Bi experimental ADS: specific approach to radiation protection aspects.

    PubMed

    Abderrahim, H Aït; Aoust, Th; Malambu, E; Sobolev, V; Van Tichelen, K; De Bruyn, D; Maes, D; Haeck, W; Van den Eynde, G

    2005-01-01

    Since 1998, SCK*CEN, in partnership with IBA s.a. and many European research laboratories, is designing a multipurpose accelerator driven system (ADS) for Research and Development (R&D) applications-MYRRHA-and is conducting an associated R&D support programme. MYRRHA is an ADS under development at Mol in Belgium and is aiming to serve as a basis for the European experimental ADS to provide protons and neutrons for various R&D applications. It consists of a proton accelerator delivering a 350 MeV x 5 mA proton beam to a liquid Pb-Bi spallation target that in turn couples to a Pb-Bi cooled, subcritical fast core. In the first stage, the project focuses mainly on demonstration of the ADS concept, safety research on sub-critical systems and nuclear waste transmutation studies. In a later stage, the device will also be dedicated to research on structural materials, nuclear fuel, liquid metal technology and associated aspects, and on sub-critical reactor physics. Subsequently, it will be used for research on applications such as radioisotope production. A first preliminary conceptual design file of MYRRHA was completed by the end of 2001 and has been reviewed by an International Technical Guidance Committee, which concluded that there are no show stoppers in the project and even though some topics such as the safety studies and the fuel qualification need to be addressed more deeply before concluding it. In this paper, we are reporting on the state-of-the art of the MYRRHA project at the beginning of 2004 and in particular on the radiation shielding assessment and the radiation protection particular aspects through a remote handling operation approach in order to minimise the personnel exposure to radiation. PMID:16604674

  5. Experimental Particle Physics

    SciTech Connect

    Rosenfeld, Carl; Mishra, Sanjib R.; Petti, Roberto; Purohit, Milind V.

    2014-08-31

    The high energy physics group at the University of South Carolina, under the leadership of Profs. S.R. Mishra, R. Petti, M.V. Purohit, J.R. Wilson (co-PI's), and C. Rosenfeld (PI), engaged in studies in "Experimental Particle Physics." The group collaborated with similar groups at other universities and at national laboratories to conduct experimental studies of elementary particle properties. We utilized the particle accelerators at the Fermi National Accelerator Laboratory (Fermilab) in Illinois, the Stanford Linear Accelerator Center (SLAC) in California, and the European Center for Nuclear Research (CERN) in Switzerland. Mishra, Rosenfeld, and Petti worked predominantly on neutrino experiments. Experiments conducted in the last fifteen years that used cosmic rays and the core of the sun as a source of neutrinos showed conclusively that, contrary to the former conventional wisdom, the "flavor" of a neutrino is not immutable. A neutrino of flavor "e," "mu," or "tau," as determined from its provenance, may swap its identity with one of the other flavors -- in our jargon, they "oscillate." The oscillation phenomenon is extraordinarily difficult to study because neutrino interactions with our instruments are exceedingly rare -- they travel through the earth mostly unimpeded -- and because they must travel great distances before a substantial proportion have made the identity swap. Three of the experiments that we worked on, MINOS, NOvA, and LBNE utilize a beam of neutrinos from an accelerator at Fermilab to determine the parameters governing the oscillation. Two other experiments that we worked on, NOMAD and MIPP, provide measurements supportive of the oscillation experiments. Good measurements of the neutrino oscillation parameters may constitute a "low energy window" on related phenomena that are otherwise unobservable because they would occur only at energies way above the reach of conceivable accelerators. Purohit and Wilson participated in the BaBar experiment

  6. Experimental impact crater morphology

    NASA Astrophysics Data System (ADS)

    Dufresne, A.; Poelchau, M. H.; Hoerth, T.; Schaefer, F.; Thoma, K.; Deutsch, A.; Kenkmann, T.

    2012-04-01

    The research group MEMIN (Multidisciplinary Experimental and Impact Modelling Research Network) is conducting impact experiments into porous sandstones, examining, among other parameters, the influence of target pore-space saturation with water, and projectile velocity, density and mass, on the cratering process. The high-velocity (2.5-7.8 km/s) impact experiments were carried out at the two-stage light-gas gun facilities of the Fraunhofer Institute EMI (Germany) using steel, iron meteorite (Campo del Cielo IAB), and aluminium projectiles with Seeberg Sandstone as targets. The primary objectives of this study within MEMIN are to provide detailed morphometric data of the experimental craters, and to identify trends and characteristics specific to a given impact parameter. Generally, all craters, regardless of impact conditions, have an inner depression within a highly fragile, white-coloured centre, an outer spallation (i.e. tensile failure) zone, and areas of arrested spallation (i.e. spall fragments that were not completely dislodged from the target) at the crater rim. Within this general morphological framework, distinct trends and differences in crater dimensions and morphological characteristics are identified. With increasing impact velocity, the volume of craters in dry targets increases by a factor of ~4 when doubling velocity. At identical impact conditions (steel projectiles, ~5km/s), craters in dry and wet sandstone targets differ significantly in that "wet" craters are up to 76% larger in volume, have depth-diameter ratios generally below 0.19 (whereas dry craters are almost consistently above this value) at significantly larger diameters, and their spallation zone morphologies show very different characteristics. In dry craters, the spall zone surfaces dip evenly at 10-20° towards the crater centre. In wet craters, on the other hand, they consist of slightly convex slopes of 10-35° adjacent to the inner depression, and of sub-horizontal tensile

  7. Experimental Harmonic Motion

    NASA Astrophysics Data System (ADS)

    Searle, G. F. C.

    2014-05-01

    1. Elementary theory of harmonic motion; 2. Experimental work in harmonic motion; Experiment 1. Determination of g by a simple pendulum; Experiment 2. Harmonic motion of a body suspended by a spring; Experiment 3. Harmonic motion of a rigid body suspended by a torsion wire; Experiment 4. Study of a system with variable moment of inertia; Experiment 5. Dynamical determination of ratio of couple to twist for a torsion wire; Experiment 6. Comparison of the moments of inertia of two bodies; Experiment 7. Experiment with a pair of inertia bars; Experiment 8. Determination of the moment of inertia of a rigid pendulum; Experiment 9. Experiment on a pendulum with variable moment of inertia; Experiment 10. Determination of g by a rigid pendulum; Experiment 11. Pendulum on a yielding support; Experiment 12. Determination of the radius of curvature of a concave mirror by the oscillations of a sphere rolling in it; Experiment 13. Determination of g by the oscillations of a rod rolling on a cylinder; Experiment 14. Study of a vibrating system with two degrees of freedom; Note 1. On the vibration of a body suspended from a light spring; Note 2. Periodic time of a pendulum vibrating through a finite arc; Note 3. Periodic time for finite motion; Note 4. Periodic times of a pendulum with two degrees of freedom.

  8. Experimental Autoimmune Breast Failure

    PubMed Central

    Kesaraju, Pavani; Jaini, Ritika; Johnson, Justin M.; Altuntas, Cengiz Z.; Gruden, Jessica J.; Sakalar, Cagri; Tuohy, Vincent K.

    2013-01-01

    Mastitis is a substantial clinical problem in lactating women that may result in severe pain and abrupt termination of breastfeeding, thereby predisposing infants to long-term health risks. Many cases of mastitis involve no known infectious agent and may fundamentally be due to autoimmune-mediated inflammation of the breast. Herein, we develop a murine model of autoimmune mastitis and provide a detailed characterization of its resulting phenotype of breast failure and lactation insufficiency. To generate breast-specific autoimmunity, we immunized SWXJ mice with recombinant mouse α-lactalbumin, a lactation-dependent, breast-specific differentiation protein critical for production of lactose. Mice immunized with α-lactalbumin showed extensive T-cell–mediated inflammation in lactating normal breast parenchyma but none in nonlactating normal breast parenchyma. This targeted autoimmune attack resulted in breast failure characterized by lactation insufficiency and decreased ability to nurture offspring. Although immunization with α-lactalbumin had no effect on fertility and birth numbers, pups nursed by α-lactalbumin–immunized mice showed significantly disrupted growth often accompanied by kwashiorkor-like nutritional abnormalities, including alopecia, liver toxicity, and runting. This experimental model of autoimmune breast failure has useful applications for prophylactic breast cancer vaccination and for addressing inflammatory complications during breastfeeding. In addition, this model is suited for investigating nutritionally based “failure-to-thrive” issues, particularly regarding the long-term implications of postnatal nutritional deprivation. PMID:22901749

  9. Experimental chloroquine retinopathy.

    PubMed

    Matsumura, M; Ohkuma, M; Tsukahara, I

    1986-01-01

    Chloroquine retinopathy was produced experimentally in the eye of the albino corydoras (one of the tropical fish) by daily administration of chloroquine (0.1 mg per os). The enucleated eyes were examined from the 14th day to 3 months after the beginning of drug administration under light and electron microscopy. The first change of retina was the appearance of membraneous cytoplasmic body (MCB) in the cytoplasm of ganglion, amacrine, bipolar and horizontal cells. MCB might be degenerated lysosome. They showed lamellar figures or crystalline lattice-like structures. Secondarily, these MCB appeared in the inner segments of photoreceptor cells. The outer segments of rod cells disappeared, and then those of cone cells. Although photoreceptor cells were diminished in number in advanced degeneration, the cells of inner nuclear layer and ganglion cells were maintained in number. The presence of MCB dose not mean death of cells. The retinal pigment epithelial cells contained MCB in its cytoplasm only in severe degenerative cases, and did not show other remarkable changes. MCB also appeared in the cytoplasm of pericytes of retinal vessels. Chloroquine is considered to damage directly photoreceptor cells most severely. PMID:3018650

  10. Experimental quantum data locking

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Cao, Zhu; Wu, Cheng; Fukuda, Daiji; You, Lixing; Zhong, Jiaqiang; Numata, Takayuki; Chen, Sijing; Zhang, Weijun; Shi, Sheng-Cai; Lu, Chao-Yang; Wang, Zhen; Ma, Xiongfeng; Fan, Jingyun; Zhang, Qiang; Pan, Jian-Wei

    2016-08-01

    Classical correlation can be locked via quantum means: quantum data locking. With a short secret key, one can lock an exponentially large amount of information in order to make it inaccessible to unauthorized users without the key. Quantum data locking presents a resource-efficient alternative to one-time pad encryption which requires a key no shorter than the message. We report experimental demonstrations of a quantum data locking scheme originally proposed by D. P. DiVincenzo et al. [Phys. Rev. Lett. 92, 067902 (2004), 10.1103/PhysRevLett.92.067902] and a loss-tolerant scheme developed by O. Fawzi et al. [J. ACM 60, 44 (2013), 10.1145/2518131]. We observe that the unlocked amount of information is larger than the key size in both experiments, exhibiting strong violation of the incremental proportionality property of classical information theory. As an application example, we show the successful transmission of a photo over a lossy channel with quantum data (un)locking and error correction.

  11. Particle physics---Experimental

    SciTech Connect

    Lord, J.J.; Boynton, P.E.; Burnett, T.H.; Wilkes, R.J.

    1991-08-21

    We are continuing a research program in particle astrophysics and high energy experimental particle physics. We have joined the DUMAND Collaboration, which is constructing a deep undersea astrophysical neutrino detector near Hawaii. Studies of high energy hadronic interactions using emulsion chamber techniques were also continued, using balloon flight exposures to ultra-high cosmic ray nuclei (JACEE) and accelerator beams. As members of the DUMAND Collaboration, we have responsibility for development a construction of critical components for the deep undersea neutrino detector facility. We have designed and developed the acoustical positioning system required to permit reconstruction of muon tracks with sufficient precision to meet the astrophysical goals of the experiment. In addition, we are making significant contributions to the design of the database and triggering system to be used. Work has been continuing in other aspects of the study of multiparticle production processes in nuclei. We are participants in a joint US/Japan program to study nuclear interactions at energies two orders of magnitude greater than those of existing accelerators, using balloon-borne emulsion chambers. On one of the flights we found two nuclear interactions of multiplicity over 1000 -- one with a multiplicity of over 2000 and pseudorapidity density {approximately} 800 in the central region. At the statistical level of the JACEE experiment, the frequency of occurrence of such events is orders of magnitude too large. We have continued our ongoing program to study hadronic interactions in emulsions exposed to high energy accelerator beams.

  12. X-38 Experimental Aerothermodynamics

    NASA Technical Reports Server (NTRS)

    Horvath, Thomas J.; Berry, Scott A.; Merski, N. Ronald; Fitzgerald, Steve M.

    2000-01-01

    The X-38 program seeks to demonstrate an autonomously returned orbital test flight vehicle to support the development of an operational Crew Return Vehicle for the International Space Station. The test flight, anticipated in 2002, is intended to demonstrate the entire mission profile of returning Space Station crew members safely back to earth in the event of medical or mechanical emergency. Integral to the formulation of the X-38 flight data book and the design of the thermal protection system, the aerothermodynamic environment is being defined through a synergistic combination of ground based testing and computational fluid dynamics. This report provides an overview of the hypersonic aerothermodynamic wind tunnel program conducted at the NASA Langley Research Center in support of the X-38 development. Global and discrete surface heat transfer force and moment, surface streamline patterns, and shock shapes were measured on scaled models of the proposed X-38 configuration in different test gases at Mach 6, 10 and 20. The test parametrics include angle of attack from 0 to 50 degs, unit Reynolds numbers from 0.3 x 10 (exp 6) to 16 x 10 (exp 6)/ ft, rudder deflections of 0, 2, and 5 deg. and body flap deflections from 0 to 30 deg. Results from hypersonic aerodynamic screening studies that were conducted as the configuration evolved to the present shape at, presented. Heavy gas simulation tests have indicated that the primary real gas effects on X-38 aerodynamics at trim conditions are expected to favorably influence flap effectiveness. Comparisons of the experimental heating and force and moment data to prediction and the current aerodynamic data book are highlighted. The effects of discrete roughness elements on boundary layer transition were investigated at Mach 6 and the development of a transition correlation for the X-38 vehicle is described. Extrapolation of ground based heating measurements to flight radiation equilibrium wall temperatures at Mach 6 and 10 were

  13. Experimental Deformation of Magnetite

    NASA Astrophysics Data System (ADS)

    Till, J. L.; Rybacki, E.; Morales, L. F. G.

    2015-12-01

    Magnetite is an important iron ore mineral and the most prominent Fe-oxide phase in the Earth's crust. The systematic occurrence of magnetite in zones of intense deformation in oceanic core complexes suggests that it may play a role in strain localization in some silicate rocks. We performed a series of high-temperature deformation experiments on synthetic magnetite aggregates and natural single crystals to characterize the rheological behavior of magnetite. As starting material, we used fine-grained magnetite powder that was hot isostatically pressed at 1100°C for several hours, resulting in polycrystalline material with a mean grain size of around 40 μm and containing 3-5% porosity. Samples were deformed to 15-20% axial strain under constant load (approximating constant stress) conditions in a Paterson-type gas apparatus for triaxial deformation at temperatures between 900 and 1100°C and 300 MPa confining pressure. The aggregates exhibit typical power-law creep behavior. At high stresses, samples deformed by dislocation creep exhibit stress exponents close to 3, revealing a transition to near-Newtonian creep with stress exponents around 1.3 at lower stresses. Natural magnetite single crystals deformed at 1 atm pressure and temperatures between 950°C and 1150 °C also exhibit stress exponents close to 3, but with lower flow stresses and a lower apparent activation energy than the aggregates. Such behavior may result from the different oxygen fugacity buffers used. Crystallographic-preferred orientations in all polycrystalline samples are very weak and corroborate numerical models of CPO development, suggesting that texture development in magnetite may be inherently slow compared with lower symmetry phases. Comparison of our results with experimental deformation data for various silicate minerals suggests that magnetite should be weaker than most silicates during ductile creep in dry igneous rocks.

  14. Experimental nuclear physics

    NASA Astrophysics Data System (ADS)

    An earlier study of unusual electromagnetic decays in (sup 86)Zr was extended in order to make comparisons with its isotone (sup 84)Sr and with (sup 84)Zr. The K=14 (t(sub 1/2) = 70 ns) high-spin isomer in (sup 176)W was found to have a 13 percent branch directly to the K=O ground-state band, one of the strongest violations of K-selection rules known. A new program to search for a predicted region of oblate deformation involving neutron deficient isotopes in the Rn/Fr/Ra region was begun. In the area of nuclear astrophysics, as part of a study of the onset of the rp-Process, a set of measurements searching for possible new resonances for (sup 14)O+(alpha) and (sup 17)F+p reactions was completed and a coincidence experiment measuring the (sup 19)F ((sup 3)He,t) (sup 19)Ne(alpha) (sup 15)O and (sup 19)F ((sup 3)He,t) (sup 19)Ne(p) (sup 18)F reactions in order to determine the rates of the (sup 18)F(p,(alpha)) (sup 15)O and (sup 18)F(p,(gamma)) (sup 19)Ne reactions was begun. Experimental measurements of (beta)n(alpha) coincidences from the (sup 15)N(d,p) (sup 16)N((beta)- (nu)) (sup 16)O((alpha)) (sup 12)C reaction have also been completed and are currently being analyzed to determine the rate of the (sup 12)C((alpha),(gamma)) reaction. In the APEX collaboration, we have completed the assembly and testing of two position-sensitive Na barrels which surround the axial silicon detector arrays and serve as the e(sup +) triggers by detecting their back-to-back annihilation quanta were completed. The HI@AGS and RHIC collaborations, construction and implementation activities associated with the space-time-tracker detector and in the design of the central detector for the PHENIX experiment were carried out. Operation of the ESTU tandem accelerator has been reliable, delivering beam on target at terminal voltages as high as 19.3 MV and running for as long as 143 days between tank openings. Fabrication and bench testing of a new negative ion source system have been completed.

  15. [Experimental nuclear physics

    SciTech Connect

    Not Available

    1992-12-01

    An earlier study of unusual electromagnetic decays in {sup 86}Zr was extended in order to make comparisons with its isotone {sup 84}Sr and with {sup 84}Zr. The K=14 (t {sub {1/2}} = 70 ns) high-spin isomer in {sup 176}W was found to have a 13% branch directly to the K=O ground-state band, one of the strongest violations of K-selection rules known. A new program to search for a predicted region of oblate deformation involving neutron deficient isotopes in the Rn/Fr/Ra region was begun. In the area of nuclear astrophysics, as part of a study of the onset of the rp-Process, a set of measurements searching for possible new resonances for {sup 14}O+{alpha} and {sup 17}F+p reactions was completed and a coincidence experiment measuring the {sup 19}F({sup 3}He,t){sup 19}Ne({alpha}){sup 15}O and {sup 19}F({sup 3}He,t){sup 19}Ne(p){sup 18}F reactions in order to determine the rates of the {sup 18}F(p,{alpha}){sup 15}O and {sup 18}F(p,{gamma}){sup 19}Ne reactions was begun. Experimental measurements of {beta}n{alpha} coincidences from the {sup 15}N(d,p){sup 16}N({beta}{sup {minus}}{nu}){sup 16}O({alpha}){sup 12}C reaction have also been completed and are currently being analyzed to determine the rate of the {sup 12}C({alpha},{gamma}) reaction. In the APEX collaboration, we have completed the assembly and testing of two position-sensitive Na barrels which surround the axial silicon detector arrays and serve as the e{sup +} triggers by detecting their back-to-back annihilation quanta were completed. The HI@AGS and RHIC collaborations, construction and implementation activities associated with the space-time-tracker detector and in the design of the central detector for the PHENIX experiment were carried out. Operation of the ESTU tandem accelerator has been reliable, delivering beam on target at terminal voltages as high as 19.3 MV and running for as long as 143 days between tank openings. Fabrication and bench testing of a new negative ion source system have been completed.

  16. The ratio R{sub dp} of the quasielastic nd {yields} p(nn) to the elastic np {yields} pn charge-exchange-process yields at the proton emitting angle {theta}{sub p,lab} = 0 deg. over 0.55-2.0 GeV neutron beam energy region. Experimental results

    SciTech Connect

    Sharov, V. I. Morozov, A. A.; Shindin, R. A.; Antonenko, V. G.; Borzakov, S. B.; Borzunov, Yu. T.; Chernykh, E. V.; Chumakov, V. F.; Dolgii, S. A.; Finger, M.; Finger, M.; Golovanov, L. B.; Guriev, D. K.; Janata, A.; Kirillov, A. D.; Kovalenko, A. D.; Krasnov, V. A.; Kuzmin, N. A.; Kurilkin, A. K.; Kurilkin, P. K.

    2009-06-15

    New experimental results on ratio R{sub dp} of the quasielastic charge-exchange yield at the outgoing proton angle {theta}{sub p,lab} = 0 deg. for the nd {yields} p(nn) reaction to the elastic np {yields} pn charge-exchange yield, are presented. The measurements were carried out at the Nuclotron of the Veksler and Baldin Laboratory of High Energies of the JINR (Dubna) at the neutron-beam kinetic energies of 0.55, 0.8, 1.0, 1.2, 1.4, 1.8, and 2.0 GeV. The intense neutron beam with small momentum spread was produced by breakup of deuterons which were accelerated and extracted to the experimental hall. In both reactions mentioned above the outgoing protons with the momenta p{sub p} approximately equal to the neutron-beam momentum p{sub n,beam} were detected in the directions close to the direction of incident neutrons, i.e., in the vicinity of the scattering angle {theta}{sub p,lab} = 0 deg. Measured in the same data-taking runs, the angular distributions of the charge-exchange-reaction products were corrected for the well-known instrumental effects and averaged in the vicinity of the incident-neutron-beam direction. These corrected angular distributions for every of nd {yields} p(nn) and np {yields} pn charge-exchange processes were proportional to the differential cross sections of the corresponding reactions. The data were accumulated by Delta-Sigma setup magnetic spectrometer with two sets of multiwire proportional chambers located upstream and downstream of the momentum analyzing magnet. Inelastic processes were considerably reduced by the additional detectors surrounding the hydrogen and deuterium targets. The time-of-flight system was applied to identify the detected particles. The accumulated data treatment and analysis, as well as possible sources of the systematic errors are discussed.

  17. Big Sisters: An Experimental Evaluation.

    ERIC Educational Resources Information Center

    Seidl, Fredrick W.

    1982-01-01

    Assessed the effects of participation in a Big Sisters' Program. The first part consisted of interviews (N=20) with pairs of Big Sisters-Little Sisters. The second part evaluated program effectiveness experimentally. Findings indicated positive relationships between pairs, and improved behavior of experimental girls versus controls. (RC)

  18. Experimental Mathematics and Computational Statistics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2009-04-30

    The field of statistics has long been noted for techniques to detect patterns and regularities in numerical data. In this article we explore connections between statistics and the emerging field of 'experimental mathematics'. These includes both applications of experimental mathematics in statistics, as well as statistical methods applied to computational mathematics.

  19. Assessing Pupils' Skills in Experimentation

    ERIC Educational Resources Information Center

    Hammann, Marcus; Phan, Thi Thanh Hoi; Ehmer, Maike; Grimm, Tobias

    2008-01-01

    This study is concerned with different forms of assessment of pupils' skills in experimentation. The findings of three studies are reported. Study 1 investigates whether it is possible to develop reliable multiple-choice tests for the skills of forming hypotheses, designing experiments and analysing experimental data. Study 2 compares scores from…

  20. Majorana Thermosyphon Prototype Experimental Setup

    SciTech Connect

    Reid, Douglas J.; Guzman, Anthony D.; Munley, John T.

    2011-08-01

    This report presents the experimental setup of Pacific Northwest National Laboratory’s MAJORANA DEMONSTRATOR thermosyphon prototype cooling system. A nitrogen thermosyphon prototype of such a system has been built and tested at PNNL. This document presents the experimental setup of the prototype that successfully demonstrated the heat transfer performance of the system.

  1. MEASUREMENT AND PRECISION, EXPERIMENTAL VERSION.

    ERIC Educational Resources Information Center

    Harvard Univ., Cambridge, MA. Harvard Project Physics.

    THIS DOCUMENT IS AN EXPERIMENTAL VERSION OF A PROGRAMED TEXT ON MEASUREMENT AND PRECISION. PART I CONTAINS 24 FRAMES DEALING WITH PRECISION AND SIGNIFICANT FIGURES ENCOUNTERED IN VARIOUS MATHEMATICAL COMPUTATIONS AND MEASUREMENTS. PART II BEGINS WITH A BRIEF SECTION ON EXPERIMENTAL DATA, COVERING SUCH POINTS AS (1) ESTABLISHING THE ZERO POINT, (2)…

  2. Experimental Laboratory Research in Counseling.

    ERIC Educational Resources Information Center

    Strong, Stanley R.

    In spite of the potential which experimental research methods affords counselors in the development of effective counseling services, such methods are seldom used. After briefly reviewing the arguments against experimental research and their underlying beliefs, the author sets out: (1) to explore the implications of using the laboratory to conduct…

  3. Animal Experimentation in High Schools

    ERIC Educational Resources Information Center

    Ansevin, Kystyna D.

    1970-01-01

    Recommends that teacher and student be provided with the broadest possible spectrum of meaningful and feasible experiments in which the comfort of the experimental animal is protected by the design of the experiment. (BR)

  4. An Experimental Text-Commentary

    ERIC Educational Resources Information Center

    O'Brien, Joan

    1976-01-01

    An experimental text-commentary of selected passages from Sophocles'"Antigone" is described. The commentary is intended for students seeking more than a conventional translation who do not know enough Greek to use a standard commentary. (RM)

  5. The Beginnings of Experimental Petrology

    ERIC Educational Resources Information Center

    Eugster, Hans P.

    1971-01-01

    An account of Van't Hoff's change from theoretical chemistry to petrology provides data on the European intellectual climate of the early 1900's and shows how his work laid the foundation for experimental petrology of hard rocks." (AL)

  6. The experimental status of |Vub|

    NASA Astrophysics Data System (ADS)

    Won, Eunil

    2009-12-01

    In this presentation, we review the current experimental status in the measurements of |Vcb| from semileptonic B??? decays to DX ℓv???. Over 10 years of impressive progress in both theoretical and experimental approaches, now less than 2% precision is achieved. In order to further improve these measurements to test standard model, one expects to have better understanding of theoretical uncertainties and to have much more data from future higher luminosity B-factories and LHCb experiment.

  7. Experimental

    NASA Astrophysics Data System (ADS)

    Gütlich, Philipp; Bill, Eckhard; Trautwein, Alfred X.

    In this chapter, we present the principles of conventional Mössbauer spectrometers with radioactive isotopes as the light source; Mössbauer experiments with synchrotron radiation are discussed in Chap. 9 including technical principles. Since complete spectrometers, suitable for virtually all the common isotopes, have been commercially available for many years, we refrain from presenting technical details like electronic circuits. We are concerned here with the functional components of a spectrometer, their interaction and synchronization, the different operation modes and proper tuning of the instrument. We discuss the properties of radioactive γ-sources to understand the requirements of an efficient γ-counting system, and finally we deal with sample preparation and the optimization of Mössbauer absorbers. For further reading on spectrometers and their technical details, we refer to the review articles [1-3].

  8. Experimental verification of dynamic simulation

    NASA Technical Reports Server (NTRS)

    Yae, K. Harold; Hwang, Howyoung; Chern, Su-Tai

    1989-01-01

    The dynamics model here is a backhoe, which is a four degree of freedom manipulator from the dynamics standpoint. Two types of experiment are chosen that can also be simulated by a multibody dynamics simulation program. In the experiment, recorded were the configuration and force histories; that is, velocity and position, and force output and differential pressure change from the hydraulic cylinder, in the time domain. When the experimental force history is used as driving force in the simulation model, the forward dynamics simulation produces a corresponding configuration history. Then, the experimental configuration history is used in the inverse dynamics analysis to generate a corresponding force history. Therefore, two sets of configuration and force histories--one set from experiment, and the other from the simulation that is driven forward and backward with the experimental data--are compared in the time domain. More comparisons are made in regard to the effects of initial conditions, friction, and viscous damping.

  9. Experimental Models for Neurotrauma Research.

    PubMed

    Davidsson, Johan; Risling, Mårten

    2016-01-01

    Physical trauma in the central nervous system (CNS) is usually the result of a number of forces in different directions and dimensions. A large number of experimental models have been developed to improve the possibilities to understand the outcome of CNS trauma. In this chapter, we will describe the need for a variety of experimental models for research on traumatic brain injury (TBI) and spinal cord injury (SCI). Models can serve different needs, such as: to test new treatments for injuries, to reveal thresholds for injuries, to provide a better understanding of injury mechanisms, or to test tools and methods for translation between experiments and clinical data. In this chapter, we will discuss on the validation of models and translation between experimental and clinical studies. PMID:27604724

  10. Experimental Approach to Teaching Fluids

    NASA Astrophysics Data System (ADS)

    Stern, Catalina

    2015-11-01

    For the last 15 years we have promoted experimental work even in the theoretical courses. Fluids appear in the Physics curriculum of the National University of Mexico in two courses: Collective Phenomena in their sophomore year and Continuum Mechanics in their senior year. In both, students are asked for a final project. Surprisingly, at least 85% choose an experimental subject even though this means working extra hours every week. Some of the experiments were shown in this congress two years ago. This time we present some new results and the methodology we use in the classroom. I acknowledge support from the Physics Department, Facultad de Ciencias, UNAM.

  11. Experimental observation of heat transparency

    NASA Astrophysics Data System (ADS)

    Zeng, Lunwu; Song, Runxia

    2014-05-01

    In this Letter, we experimentally observed heat diffusion transparency with the heat diffusion device we fabricated, which can measure time-dependent temperature. Utilizing the effective medium theory, we fabricated an isotropic spherical shell with an isotropic spherical core, as well as a multilayer isotropic spherical shell with an isotropic spherical core as neutral inclusions. We measured the temperatures and temperature gradients outside the neutral inclusions with the self-made heat diffusion device and analyzed the heat transparent conditions. The experimental results show that the temperature gradients are parallel and equal outside the neutral inclusion, and the iso-temperature lines are also parallel outside the neutral inclusion.

  12. Big Explosives Experimental Facility - BEEF

    SciTech Connect

    2014-10-31

    The Big Explosives Experimental Facility or BEEF is a ten acre fenced high explosive testing facility that provides data to support stockpile stewardship and other national security programs. At BEEF conventional high explosives experiments are safely conducted providing sophisticated diagnostics such as high speed optics and x-ray radiography.

  13. Experimental Neutrino Physics: Final Report

    SciTech Connect

    Lane, Charles E.; Maricic, Jelena

    2012-09-05

    Experimental studies of neutrino properties, with particular emphasis on neutrino oscillation, mass and mixing parameters. This research was pursued by means of underground detectors for reactor anti-neutrinos, measuring the flux and energy spectra of the neutrinos. More recent investigations have been aimed and developing detector technologies for a long-baseline neutrino experiment (LBNE) using a neutrino beam from Fermilab.

  14. The drawing of experimental curves

    NASA Technical Reports Server (NTRS)

    Norton, F H

    1921-01-01

    This report presents a discussion of how to determine the location of a line or surface from experimental data. What we desire to know practically is the number of ordinates required to obtain a certain probable precision in drawing a line or surface.

  15. An experimenter and his methodology

    NASA Astrophysics Data System (ADS)

    Filonovich, S. R.

    1990-12-01

    A review of experimental works by Ernst Mach has been given. The works reffer to optics and acoustics. The author is representing Ernst Mach as a physicist rather than a phylosopher, which contradicts the point of view obviously accepted in Soviet history of sciences and philosophy.

  16. Experimental medicine 1000 years ago

    PubMed Central

    Abdel-Halim, Rabie E.

    2011-01-01

    Little is known about the state of experimentation in the field of medicine during the Medieval Islamic era. With few exceptions, most of the contemporary sources on history of medicine propagate the idea that the roots of experimental medicine in its modern form, including clinical trials and drug-potency studies, first started during the European Renaissance in the 16th to the 18th centuries. This study is part of an ongoing multidisciplinary primary-source investigation of the original Arabic works of 11 Islamic medical scholars who lived and practiced between the 9th and the 13th centuries. The study critically evaluated and documented their contributions to the development of the scientific method and experimental medicine during that medieval Islamic era in several areas including critical appraisal of previous knowledge, clinical observations and case reports, clinical therapeutic trials, drug potency trials, experimentation on animals, dissection and dissection experiments as well as postmortem examinations. In each of the above-mentioned areas, significant contributions were made during the Medieval Islamic era from as early as the ninth century AD. PMID:21747591

  17. Experimental medicine 1000 years ago.

    PubMed

    Abdel-Halim, Rabie E

    2011-05-01

    Little is known about the state of experimentation in the field of medicine during the Medieval Islamic era. With few exceptions, most of the contemporary sources on history of medicine propagate the idea that the roots of experimental medicine in its modern form, including clinical trials and drug-potency studies, first started during the European Renaissance in the 16(th) to the 18(th) centuries. This study is part of an ongoing multidisciplinary primary-source investigation of the original Arabic works of 11 Islamic medical scholars who lived and practiced between the 9(th) and the 13(th) centuries. The study critically evaluated and documented their contributions to the development of the scientific method and experimental medicine during that medieval Islamic era in several areas including critical appraisal of previous knowledge, clinical observations and case reports, clinical therapeutic trials, drug potency trials, experimentation on animals, dissection and dissection experiments as well as postmortem examinations. In each of the above-mentioned areas, significant contributions were made during the Medieval Islamic era from as early as the ninth century AD. PMID:21747591

  18. Experimental investigations of ICRF effects

    SciTech Connect

    Not Available

    1991-01-01

    The goal of the Phaedrus program is to establish the relative efficiency of helicity and momentum current drive for rf near and below omega{sub ci} and compare to theory. This paper discusses major accomplishments in the rf program; extension of operating parameters; facility improvements; and additional experimental activities. (LSP)

  19. Evaluating E-Labs' Experimentation

    ERIC Educational Resources Information Center

    Plaisent, Michel; Maguiraga, Lassana; Bernard, Prosper; Larhrib, Samir

    2004-01-01

    This communication discusses preliminary results on an experimentation of e-Learning with MIS students, mainly in order to cope with the logistics of lab organization. A learning management software was installed which changed completely the learning process, from content to logistics. Students have expressed their satisfaction with the e-Learning…

  20. Big Explosives Experimental Facility - BEEF

    ScienceCinema

    None

    2015-01-07

    The Big Explosives Experimental Facility or BEEF is a ten acre fenced high explosive testing facility that provides data to support stockpile stewardship and other national security programs. At BEEF conventional high explosives experiments are safely conducted providing sophisticated diagnostics such as high speed optics and x-ray radiography.

  1. An Experimental Approach To… Everything!

    ERIC Educational Resources Information Center

    Orr, Taylor; Flowers, Jim

    2014-01-01

    The goal of formal education is student learning. By emphasizing experimentation in the classroom or lab, students learn about the results of a particular inquiry. But more importantly, they learn to refine their approach to learning by creating new knowledge rather than merely remembering what they have been told. An inquiry approach where…

  2. On the New Experimental Syllabus.

    ERIC Educational Resources Information Center

    Soviet Education, 1989

    1989-01-01

    Presents an experimental secondary school curriculum as drafted by the Soviet Union's Ministry of Education in 1987. Intended for implementation (after modifications) by the year 2000, as part of perestroika and educational reform. Examines the curriculum's rationale. Lists school subjects, indicating number of hours and grades in which they…

  3. Experimental Nuclear Physics with INFN

    SciTech Connect

    Bracco, Angela

    2009-05-04

    An overview of the experimental activities in Nuclear Physics carried out by Italian researchers and funded by INFN is presented. The experimental program addresses a number of key problems of modern nuclear physics in the fields of hadron dynamics, quark gluon plasma, nuclear structure and reaction dynamics and nuclear astrophysics. The experiments are performed at the four national laboratories, at CERN and several other laboratories abroad. In particular, LNL is mainly dedicated to nuclear structure, LNS is strongly involved in the study of equation of state and nuclear astrophysics, LNF has a program on hypernuclei and kaonic atoms and LNGS has a facility for measurements of cross sections of astrophysical interest. The large community working on the problem of quark gluon plasma is very active in the ALICE experiment which will use the ultrarelativisc heavy ion collisions of LHC. Interdisciplinary researches are also supported. A brief outline of the future perspectives is here given.

  4. Experimental research on air propellers

    NASA Technical Reports Server (NTRS)

    Durand, William F

    1918-01-01

    The purposes of the experimental investigation on the performance of air propellers described in this report are as follows: (1) the development of a series of design factors and coefficients drawn from model forms distributed with some regularity over the field of air-propeller design and intended to furnish a basis of check with similar work done in other aerodynamic laboratories, and as a point of departure for the further study of special or individual types and forms; (2) the establishment of a series of experimental values derived from models and intended for later use as a basis for comparison with similar results drawn from certain selected full-sized forms and tested in free flight.

  5. Experimental lithium system. Final report

    SciTech Connect

    Kolowith, R.; Berg, J.D.; Miller, W.C.

    1985-04-01

    A full-scale mockup of the Fusion Materials Irradiation Test (FMIT) Facility lithium system was built at the Hanford Engineering Development Laboratory (HEDL). This isothermal mockup, called the Experimental Lithium System (ELS), was prototypic of FMIT, excluding the accelerator and dump heat exchanger. This 3.8 m/sup 3/ lithium test loop achieved over 16,000 hours of safe and reliable operation. An extensive test program demonstrated satisfactory performance of the system components, including the HEDL-supplied electromagnetic lithium pump, the lithium jet target, the purification and characterization hardware, as well as the auxiliary argon and vacuum systems. Experience with the test loop provided important information on system operation, performance, and reliability. This report presents a complete overview of the entire Experimental Lithium System test program and also includes a summary of such areas as instrumentation, coolant chemistry, vapor/aerosol transport, and corrosion.

  6. Experimental unconditionally secure bit commitment.

    PubMed

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adán; Pan, Jian-Wei

    2014-01-10

    Quantum physics allows for unconditionally secure communication between parties that trust each other. However, when the parties do not trust each other such as in the bit commitment scenario, quantum physics is not enough to guarantee security unless extra assumptions are made. Unconditionally secure bit commitment only becomes feasible when quantum physics is combined with relativistic causality constraints. Here we experimentally implement a quantum bit commitment protocol with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. The security of the protocol relies on the properties of quantum information and relativity theory. In each run of the experiment, a bit is successfully committed with less than 5.68×10(-2) cheating probability. This demonstrates the experimental feasibility of quantum communication with relativistic constraints. PMID:24483878

  7. Experimental unconditionally secure bit commitment

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adan; Pan, Jian-Wei

    2014-03-01

    Quantum physics allows unconditionally secure communication between parties that trust each other. However, when they do not trust each other such as in the bit commitment, quantum physics is not enough to guarantee security. Only when relativistic causality constraints combined, the unconditional secure bit commitment becomes feasible. Here we experimentally implement a quantum bit commitment with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. Bits are successfully committed with less than 5 . 68 ×10-2 cheating probability. This provides an experimental proof of unconditional secure bit commitment and demonstrates the feasibility of relativistic quantum communication.

  8. Experimental Unconditionally Secure Bit Commitment

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Cao, Yuan; Curty, Marcos; Liao, Sheng-Kai; Wang, Jian; Cui, Ke; Li, Yu-Huai; Lin, Ze-Hong; Sun, Qi-Chao; Li, Dong-Dong; Zhang, Hong-Fei; Zhao, Yong; Chen, Teng-Yun; Peng, Cheng-Zhi; Zhang, Qiang; Cabello, Adán; Pan, Jian-Wei

    2014-01-01

    Quantum physics allows for unconditionally secure communication between parties that trust each other. However, when the parties do not trust each other such as in the bit commitment scenario, quantum physics is not enough to guarantee security unless extra assumptions are made. Unconditionally secure bit commitment only becomes feasible when quantum physics is combined with relativistic causality constraints. Here we experimentally implement a quantum bit commitment protocol with relativistic constraints that offers unconditional security. The commitment is made through quantum measurements in two quantum key distribution systems in which the results are transmitted via free-space optical communication to two agents separated with more than 20 km. The security of the protocol relies on the properties of quantum information and relativity theory. In each run of the experiment, a bit is successfully committed with less than 5.68×10-2 cheating probability. This demonstrates the experimental feasibility of quantum communication with relativistic constraints.

  9. Melioration and self-experimentation

    PubMed Central

    Neuringer, Allen

    1984-01-01

    Operant researchers rarely use the arena of applied psychology to motivate or to judge their research. Absence of tests by application weakens the field of basic operant research. Early in their development, the physical and biological sciences emphasized meliorative aspects of research. Improvement of human life was a major goal of these young sciences. This paper argues that if basic operant researchers analogously invoked a melioration criterion, the operant field might avoid its tendency toward ingrowth and instead generate a broadly influential science. Operant researchers could incorporate melioration by (a) creating animal models to study applied problems; (b) confronting questions raised by applied analysts and testing hypotheses in applied settings; or (c) performing self-experiments—that is, using experimental methods and behavioral techniques to study and change the experimenter's behavior. PMID:16812398

  10. Experimental multilocation remote state preparation

    NASA Astrophysics Data System (ADS)

    Rådmark, Magnus; Wieśniak, Marcin; Żukowski, Marek; Bourennane, Mohamed

    2013-09-01

    Transmission of quantum states is a central task in quantum information science. Remote state preparation (RSP) has the same goal as teleportation, i.e., transferring quantum information without sending physically the information carrier, but in RSP the sender knows the state which is to be transmitted. We present experimental demonstrations of RSP for two and three locations. In our experimental scheme Alice (the preparer) and her three partners share four and six photon polarization entangled singlets. This allows us to perform RSP of two or three copies of a single-qubit state, a two-qubit Bell state, and a three-qubit W, or W¯ state. A possibility to prepare two-qubit nonmaximally entangled and GHZ states is also discussed. The ability to remotely prepare an entangled states by local projections at Alice is a distinguishing feature of our scheme.

  11. Elements of Bayesian experimental design

    SciTech Connect

    Sivia, D.S.

    1997-09-01

    We consider some elements of the Bayesian approach that are important for optimal experimental design. While the underlying principles used are very general, and are explained in detail in a recent tutorial text, they are applied here to the specific case of characterising the inferential value of different resolution peakshapes. This particular issue was considered earlier by Silver, Sivia and Pynn (1989, 1990a, 1990b), and the following presentation confirms and extends the conclusions of their analysis.

  12. Experimental Cardiac Necrosis and Potassium

    PubMed Central

    Prioreschi, P.

    1967-01-01

    In recent years evidence has been brought forward supporting the hypothesis that myocardial infarction is not due to thrombotic occlusion of a coronary artery but to a metabolic derangement in a myocardium “conditioned” by coronary atherosclerosis. The author briefly reviews metabolic necroses experimentally induced in the animal and discusses the action of potassium in preventing their development. The basis for the clinical use of potassium and magnesium salts for the prevention of myocardial infarction is also discussed. PMID:5336956

  13. Multiphase combustion experimentation in microgravity

    NASA Technical Reports Server (NTRS)

    Berlad, A. L.

    1983-01-01

    This paper examines the need for and implementation of microgravity combustion studies of two phase media. Experimental and analytical aspects of several heterogeneous kinetic systems are discussed. These include: flame propagation and extinction for quiescent clouds of uniformly premixed fuel particulates in an oxidizing atmosphere; autoignition of clouds of uniformly premixed fuel particulates in a quiescent oxidizing atmosphere; and the roles of catalytically significant surfaces in gaseous autoignition processes.

  14. Experimental Mathematics and Mathematical Physics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.; Broadhurst, David; Zudilin, Wadim

    2009-06-26

    One of the most effective techniques of experimental mathematics is to compute mathematical entities such as integrals, series or limits to high precision, then attempt to recognize the resulting numerical values. Recently these techniques have been applied with great success to problems in mathematical physics. Notable among these applications are the identification of some key multi-dimensional integrals that arise in Ising theory, quantum field theory and in magnetic spin theory.

  15. Experimental realization of invisibility cloaking

    NASA Astrophysics Data System (ADS)

    Shchelokova, A. V.; Melchakova, I. V.; Slobozhanyuk, A. P.; Yankovskaya, E. A.; Simovski, C. R.; Belov, P. A.

    2015-02-01

    Advances in the studies of metamaterials have pushed the development of invisibility cloaks, which suppress scattering by objects within certain frequency ranges. During recent years, there has been a transition from a purely theoretical consideration of the cloaking effect to its practical implementation. This paper is an overview of the current state of the art in the area of invisibility cloaks. Special emphasis is put on experimental realizations of such devices.

  16. Experimental tests of quantum chromodynamics

    SciTech Connect

    Dorfan, J.

    1987-04-01

    Experimental tests of quantum chromodynamics are discussed in the e/sup +/e/sup -/ continuum, in pp and anti p p collisions, in measurements of ..cap alpha../sub s/ from UPSILON decays, in deep inelastic lepton scattering, and in the measurement of the photon structure function. A large body of data relating to the testing of quantum chromodynamics is reviewed, showing qualitative agreement between the data from a wide range of processes and QCD. 66 refs., 79 figs. (LEW)

  17. Does experimental research support psychoanalysis?

    PubMed

    Cohen, David

    2011-12-01

    The question of whether a psychodynamic view is compatible with experimental research is still a challenging issue-especially for child and adolescent psychopathology-despite the influence of psychoanalytic theory in this field until the 1980s. In this article, is explored the relationship between psychodynamic theory and experimental research using examples of evidence-based studies in the fields of (i) psychotherapeutic intervention assessment, (ii) placebo response in children and adolescents, (iii) unconscious lasting traumatic effects in children and adolescents, (iv) psychodynamic-oriented psychological testing. There are now a sufficient number of evidence-based studies to support the use of psychodynamic therapy in mental disorders, particularly in personality disorder and anxious/depressive disorder. In addition, placebo responses in children and adolescents with internalizing disorders are significantly higher in major depression compared to obsessive-compulsive disorder or other anxiety disorders, which highlights differential psychopathologies regarding the experience of loss. Also, using an experimental task, psychoanalysts are able to identify, without explicit knowledge and above the level of chance, healthy adults whose siblings had experienced cancer during childhood. This experiment suggests that implicit information regarding a participant's history is conveyed in interpersonal exchanges that can be intuitively perceived by judges experienced in listening to free associations from a psychodynamic perspective. Finally, psychodynamic-oriented psychological testing may predict the transition to schizophrenia in adolescents with a history of manic/mixed episodes. It can be concluded that there are no discrepancies between psychodynamic views and experimental data, whether one tests psychotherapeutic approaches, discusses data from other fields such as psychopharmacology, or designs experiments based on psychodynamic theory. PMID:21963530

  18. Experimental Crystallization of Yamato 980459

    NASA Technical Reports Server (NTRS)

    Jones, John H.; Galenas, M. G.; Danielson, L. R.

    2009-01-01

    Currently, only two martian meteorites QUE 94201 (QUE) and Yamato 980459 (Y98) have been experimentally shown to me true melt compositions. Most martian meteorites are instead, cumulates or partial cumulates. We have performed experiments on a Y98 composition to assess whether QUE could be related to Y98 by some fractionation process [1]. Y98 is a basaltic shergottite from the SNC (Shergotty, Nakhla, Chassigny) meteorite group. Y98 is composed of 26% olivine, 48% pyroxene, 25% mesostasis, and no plagioclase [2]. The large size of the olivine megacrysts and absence of plagioclase suggest that the parental melt which formed this meteorite had begun cooling slowly until some mechanism, such as magma ascent, caused rapid cooling [3]. Y98 s olivines have the highest Mg content of all the shergottites suggesting that it is the most primitive [4]. Y98 has been determined to be a melt composition by comparing the composition of experimental liquidus olivines with the composition of the cores of Y98 olivines [4]. The liquidus of Y98 is predicted by MELTS [5] and by experimentation [6] to be 1450 C. Analyses of Y98 show it to be very depleted in LREEs and it has similar depleted patterns as other shergottites such as QUE [7].

  19. National Ignition Facility: Experimental plan

    SciTech Connect

    Not Available

    1994-05-01

    As part of the Conceptual Design Report (CDR) for the National Ignition Facility (NIF), scientists from Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL), the University of Rochester`s Laboratory for Laser Energetics (UR/LLE), and EG&G formed an NIF Target Diagnostics Working Group. The purpose of the Target Diagnostics Working Group is to prepare conceptual designs of target diagnostics for inclusion in the facility CDR and to determine how these specifications impact the CDR. To accomplish this, a subgroup has directed its efforts at constructing an approximate experimental plan for the ignition campaign of the NIF CDR. The results of this effort are contained in this document, the Experimental Plan for achieving fusion ignition in the NIF. This group initially concentrated on the flow-down requirements of the experimental campaign leading to ignition, which will dominate the initial efforts of the NIF. It is envisaged, however, that before ignition, there will be parallel campaigns supporting weapons physics, weapons effects, and other research. This plan was developed by analyzing the sequence of activities required to finally fire the laser at the level of power and precision necessary to achieve the conditions of an ignition hohlraum target, and to then use our experience in activating and running Nova experiments to estimate the rate of completing these activities.

  20. Nonisothermal hydrologic transport experimental plan

    SciTech Connect

    Rasmussen, T.C.; Evans, D.D.

    1992-09-01

    A field heater experimental plan is presented for investigating hydrologic transport processes in unsaturated fractured rock related to the disposal of high-level radioactive waste (HLW) in an underground repository. The experimental plan provides a methodology for obtaining data required for evaluating conceptual and computer models related to HLW isolation in an environment where significant heat energy is produced. Coupled-process models are currently limited by the lack of validation data appropriate for field scales that incorporate relevant transport processes. Presented in this document is a discussion of previous nonisothermal experiments. Processes expected to dominate heat-driven liquid, vapor, gas, and solute flow during the experiment are explained, and the conceptual model for nonisothermal flow and transport in unsaturated, fractured rock is described. Of particular concern is the ability to confirm the hypothesized conceptual model specifically, the establishment of higher water saturation zones within the host rock around the heat source, and the establishment of countercurrent flow conditions within the host rock near the heat source. Field experimental plans are presented using the Apache Leap Tuff Site to illustrate the implementation of the proposed methodology. Both small-scale preliminary experiments and a long-term experiment are described.

  1. Experimental understanding of wildland fires

    NASA Astrophysics Data System (ADS)

    Simeoni, A.

    2012-04-01

    The experimental study of natural fires to better understand their behaviour and develop fire-spread models is the topic of a very large literature. Experimental activities cover many subjects related to wildland fires including among others: fire behaviour, fire impact, fuel characterization, fire emissions and fire detection. This presentation is focused on the experiments, particularly the spreading and burning dynamic of the flame front. It does not intent to be exhaustive but aims to an overview of research in the the last decades. The experimental approach in wildland fire behaviour follows the classical empirical scientific approach: observe the phenomenon to understand it, develop models to describe it and use experiments to implement and test the models. Therefore, experiments are intimately linked with the development of modelling. Experiments are developed to increase our understanding of the chemical and physical phenomena that drive fire ignition, spread and extinction, upon which fire spread models are built. Other experiments are developed to set model parameters and to validate the predictions. The work is divided into the different scales of the physical and chemical phenomena: the micro-scale, the small and large-scale laboratory scale and the field-scale.

  2. 47 CFR 73.1510 - Experimental authorizations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... experimental transmissions. (d) The FCC may request a report of the research, experimentation and results at... 47 Telecommunication 4 2010-10-01 2010-10-01 false Experimental authorizations. 73.1510 Section 73... BROADCAST SERVICES Rules Applicable to All Broadcast Stations § 73.1510 Experimental authorizations....

  3. The philosophy of scientific experimentation: a review

    PubMed Central

    2009-01-01

    Practicing and studying automated experimentation may benefit from philosophical reflection on experimental science in general. This paper reviews the relevant literature and discusses central issues in the philosophy of scientific experimentation. The first two sections present brief accounts of the rise of experimental science and of its philosophical study. The next sections discuss three central issues of scientific experimentation: the scientific and philosophical significance of intervention and production, the relationship between experimental science and technology, and the interactions between experimental and theoretical work. The concluding section identifies three issues for further research: the role of computing and, more specifically, automating, in experimental research, the nature of experimentation in the social and human sciences, and the significance of normative, including ethical, problems in experimental science. PMID:20098589

  4. EXPERIMENTAL MODELLING OF AORTIC ANEURYSMS

    PubMed Central

    Doyle, Barry J; Corbett, Timothy J; Cloonan, Aidan J; O’Donnell, Michael R; Walsh, Michael T; Vorp, David A; McGloughlin, Timothy M

    2009-01-01

    A range of silicone rubbers were created based on existing commercially available materials. These silicones were designed to be visually different from one another and have distinct material properties, in particular, ultimate tensile strengths and tear strengths. In total, eleven silicone rubbers were manufactured, with the materials designed to have a range of increasing tensile strengths from approximately 2-4MPa, and increasing tear strengths from approximately 0.45-0.7N/mm. The variations in silicones were detected using a standard colour analysis technique. Calibration curves were then created relating colour intensity to individual material properties. All eleven materials were characterised and a 1st order Ogden strain energy function applied. Material coefficients were determined and examined for effectiveness. Six idealised abdominal aortic aneurysm models were also created using the two base materials of the study, with a further model created using a new mixing technique to create a rubber model with randomly assigned material properties. These models were then examined using videoextensometry and compared to numerical results. Colour analysis revealed a statistically significant linear relationship (p<0.0009) with both tensile strength and tear strength, allowing material strength to be determined using a non-destructive experimental technique. The effectiveness of this technique was assessed by comparing predicted material properties to experimentally measured methods, with good agreement in the results. Videoextensometry and numerical modelling revealed minor percentage differences, with all results achieving significance (p<0.0009). This study has successfully designed and developed a range of silicone rubbers that have unique colour intensities and material strengths. Strengths can be readily determined using a non-destructive analysis technique with proven effectiveness. These silicones may further aid towards an improved understanding of the

  5. Theoretical and Experimental DNA Computation

    NASA Astrophysics Data System (ADS)

    Amos, Martyn

    This book provides a broad overview of the entire field of DNA computation, tracing its history and development. It contains detailed descriptions of all major theoretical models and experimental results to date, which are lacking in existing texts, and discusses potential future developments. It also provides a useful reference source for researchers and students, and an accessible introduction for people new to the field. The field of DNA computation has flourished since the publication of Adleman's seminal article, in which he demonstrated for the first time how a computation may be performed at a molecular level by performing standard operations on a tube of DNA strands.

  6. Experimental studies of glass refining

    NASA Technical Reports Server (NTRS)

    Subramanian, R. S.; Cole, R.; Kondos, P.

    1984-01-01

    The basic components of the experimental apparatus were selected and acquired. Techniques were developed for the fabrication of the special crucibles necessary for the experiments. Arrangements were made for the analysis of glass and gas bubble samples for composition information. Donations of major equipment were received for this project from Owens, Illinois where a similar study had been conducted a few year ago. Decisions were made regarding the actual glass composition to be used, the gas to be used in the first experiments, and the temperatures at which the experiments should be conducted. A microcomputer was acquired, and work was begun on interfacing the video analyzer to it.

  7. A simple Cavendish experimental apparatus

    NASA Astrophysics Data System (ADS)

    Kossler, W. J.; Klein, Susann; Morrow, Dominick; Juliao, Andre

    2016-03-01

    A simple Cavendish apparatus is described that allows measurement of the gravitational constant G and makes observable the gravitational attraction between commonplace objects. The apparatus consists of a torsion balance constructed from readily available materials, including lead bricks and fishing weights ("sinkers"). A computer program is used to determine the gravitational field at the location of the small mass due to a nearby lead brick, which allows students to gain experience with numerical methods. Experimental results obtained are compatible with the accepted value of G.

  8. The updated experimental proteinoid model

    NASA Technical Reports Server (NTRS)

    Fox, S. W.; Nakashima, T.; Przybylski, A.; Syren, R. M.

    1982-01-01

    The experimental proteinoid model includes new results indicating that polymers sufficiently rich in basic amino acid catalyze the synthesis of peptides from ATP and amino acids and of oligonucleotides from ATP. The need for simulation syntheses of amino acids yielding significant proportions of basic amino acids is now in focus. The modeled simultaneous protocellular synthesis of peptides and polynucleotides is part of a more comprehensive proposal for the origin of the coded genetic mechanism. The finding of membrane and action potentials in proteinoid microspheres, with or without added lecithin, is reported. The crucial nature of a nonrandom matrix for protocells is developed.

  9. Experimental Trauma Models: An Update

    PubMed Central

    Frink, Michael; Andruszkow, Hagen; Zeckey, Christian; Krettek, Christian; Hildebrand, Frank

    2011-01-01

    Treatment of polytrauma patients remains a medical as well as socioeconomic challenge. Although diagnostics and therapy improved during the last decades, multiple injuries are still the major cause of fatalities in patients below 45 years of age. Organ dysfunction and organ failure are major complications in patients with major injuries and contribute to mortality during the clinical course. Profound understanding of the systemic pathophysiological response is crucial for innovative therapeutic approaches. Therefore, experimental studies in various animal models are necessary. This review is aimed at providing detailed information of common trauma models in small as well as in large animals. PMID:21331361

  10. Experimental study of vortex diffusers

    SciTech Connect

    Shakerin, S.; Miller, P.L.

    1995-11-01

    This report documents experimental research performed on vortex diffusers used in ventilation and air-conditioning systems. The main objectives of the research were (1) to study the flow characteristics of isothermal jets issuing from vortex diffusers, (2) to compare the vortex diffuser`s performance with that of a conventional diffuser, and (3) to prepare a report that disseminates the results to the designers of ventilation and air-conditioning systems. The researchers considered three diffusers: a conventional round ceiling diffuser and two different styles of vortex diffusers. Overall, the vortex diffusers create slightly more induction of ambient air in comparison to the conventional diffuser.

  11. Experimental Cryosurgery Investigations In Vivo

    PubMed Central

    Gage, A.A.; Baust, J.M.; Baust, J.G.

    2009-01-01

    Cryosurgery is the use of freezing temperatures to elicit an ablative response in a targeted tissue. This review provides a global overview of experimentation in vivo which has been the basis of advancement of this widely applied therapeutic option. The cellular and tissue-related events that underlie the mechanisms of destruction, including direct cell injury (cryolysis), vascular stasis, apoptosis and necrosis, are described and are related to the optimal methods of technique of freezing to achieve efficacious therapy. In vivo experiments with major organs, including wound healing, the putative immunological response following thawing, and the use of cryoadjunctive strategies to enhance cancer cell sensitivity to freezing, are described. PMID:19833119

  12. Engine Combustion Network Experimental Data

    DOE Data Explorer

    Maintained by the Engine Combustion Department of Sandia National Laboratories, data currently available on the website includes reacting and non-reacting sprays in a constant-volume chamber at conditions typical of diesel combustion. The data are useful for model development and validation because of the well-defined boundary conditions and the wide range of conditions employed. A search utility displays data based on experimental conditions such as ambient temperature, ambient density, injection pressure, nozzle size, fuel, etc. Experiment-related visualizations are also available. (Specialized Interface)

  13. Experimental Plasma Research project summaries

    SciTech Connect

    1980-09-01

    This report contains descriptions of the activities supported by the Experimental Plasma Research Branch of APP. The individual project summaries were prepared by the principal investigators and include objectives and milestones for each project. The projects are arranged in six research categories: Plasma Properties; Plasma Heating; Plasma Diagnostics; Atomic, Molecular and Nuclear Physics; Advanced Superconducting Materials; and the Fusion Plasma Research Facility (FPRF). Each category is introduced with a statement of objectives and recent progress and followed by descriptions of individual projects. An overall budget summary is provided at the beginning of the report.

  14. Experimental test accelerator (ETA) II

    SciTech Connect

    Fessenden, T.J.; Atchison, W.L.; Birx, D.L.

    1981-03-06

    The Experimental Test Accelerator (ETA) is designed to produce a 10 kAmp electron beam at an energy of 4.5 MeV in 40 nsec pulses at an average rate of 2 pps. The accelerator also operates in bursts of 5 pulses spaced by as little as one millisec at an average rate of 5 pps. The machine is currently operating near 80% of its design values and has accumulated over 2.5 million pulses - mostly at a rate of one pps. The plasma cathode electron source, the remainder of the accelerator, and the operating characteristics of the machine are discussed.

  15. Experimental Modeling of Proliferative Vitreoretinopathy. An Experimental Morphological Study.

    PubMed

    Khoroshilova-Maslova, I P; Leparskaya, N L; Nabieva, M M; Andreeva, L D

    2015-05-01

    A model of proliferative vitreoretinopathy induced by simultaneous intravitreal injection of recombinant IL-1β and platelet concentrate is created and its main morphological manifestations are studied on Chinchilla rabbits. The model reflects pathogenesis of proliferative vitreoretinopathy: epiretinal membrane with the formation of retinal plication, traction detachment of the retina; moderate inflammatory reaction in the uveal tract, in the optic nerve infundibulum, in the vitreous body; intact structural elements of the retina, dissociation of the retinal pigmented epithelium cells with their subsequent migration. The model is adequate to the clinical picture of proliferative vitreoretinopathy in humans, which recommends it for experimental studies of the efficiency of drug therapy and prevention of this disease. PMID:26033599

  16. Experimental evolution in biofilm populations

    PubMed Central

    Steenackers, Hans P.; Parijs, Ilse; Foster, Kevin R.; Vanderleyden, Jozef

    2016-01-01

    Biofilms are a major form of microbial life in which cells form dense surface associated communities that can persist for many generations. The long-life of biofilm communities means that they can be strongly shaped by evolutionary processes. Here, we review the experimental study of evolution in biofilm communities. We first provide an overview of the different experimental models used to study biofilm evolution and their associated advantages and disadvantages. We then illustrate the vast amount of diversification observed during biofilm evolution, and we discuss (i) potential ecological and evolutionary processes behind the observed diversification, (ii) recent insights into the genetics of adaptive diversification, (iii) the striking degree of parallelism between evolution experiments and real-life biofilms and (iv) potential consequences of diversification. In the second part, we discuss the insights provided by evolution experiments in how biofilm growth and structure can promote cooperative phenotypes. Overall, our analysis points to an important role of biofilm diversification and cooperation in bacterial survival and productivity. Deeper understanding of both processes is of key importance to design improved antimicrobial strategies and diagnostic techniques. PMID:26895713

  17. Bacterial translocation in experimental uremia.

    PubMed

    de Almeida Duarte, Joãn Bosco; de Aguilar-Nascimento, José Eduardo; Nascimento, Mariana; Nochi, Rubens Jardim

    2004-08-01

    The aim of this study was to investigate whether or not experimental uremia would induce bacterial translocation. Forty male Wistar rats were randomized into two groups: uremic (n = 20) and control (n = 20). Under anesthesia, the upper and lower left renal poles and the marginal lateral parenchyma were excised in uremic group. Seven days later, in a second operation, the liver, spleen and the mesenteric lymph nodes (MLN) were excised and cultured. Blood samples were sent for biochemical analysis (BUN, creatinine, sodium and potassium) and cultured. Specimens of the jejunum (1 cm below the Treitz angle) and ileum (1 cm above the ileocecal valve) were collected and sent for histological examination and scored for the degree of inflammation of the mucosa using a classification proposed by Chiu et al. in 1970. Uremic rats presented higher BUN, creatinine and potassium than controls. Bacterial translocation was more frequent in uremic than in control animals (8/20 (40%) vs. 1/20 (5%); p = 0.02). Translocation in uremic rats was observed mainly at the MLN (all eight cases). Both at the jejunum (uremic = 3 [0-5] vs. control = 2 [0-4]; p = 0.04) and the ileum (uremic - 2 [0-5] vs. control = 0 [0-3]; p = 0.01), inflammation score was higher in uremic rats than in controls. The intestinal mucosa barrier is impaired and bacterial translocation occurs in experimental uremia. PMID:15497213

  18. Experimental evolution in biofilm populations.

    PubMed

    Steenackers, Hans P; Parijs, Ilse; Foster, Kevin R; Vanderleyden, Jozef

    2016-05-01

    Biofilms are a major form of microbial life in which cells form dense surface associated communities that can persist for many generations. The long-life of biofilm communities means that they can be strongly shaped by evolutionary processes. Here, we review the experimental study of evolution in biofilm communities. We first provide an overview of the different experimental models used to study biofilm evolution and their associated advantages and disadvantages. We then illustrate the vast amount of diversification observed during biofilm evolution, and we discuss (i) potential ecological and evolutionary processes behind the observed diversification, (ii) recent insights into the genetics of adaptive diversification, (iii) the striking degree of parallelism between evolution experiments and real-life biofilms and (iv) potential consequences of diversification. In the second part, we discuss the insights provided by evolution experiments in how biofilm growth and structure can promote cooperative phenotypes. Overall, our analysis points to an important role of biofilm diversification and cooperation in bacterial survival and productivity. Deeper understanding of both processes is of key importance to design improved antimicrobial strategies and diagnostic techniques. PMID:26895713

  19. Animal husbandry and experimental design.

    PubMed

    Nevalainen, Timo

    2014-01-01

    If the scientist needs to contact the animal facility after any study to inquire about husbandry details, this represents a lost opportunity, which can ultimately interfere with the study results and their interpretation. There is a clear tendency for authors to describe methodological procedures down to the smallest detail, but at the same time to provide minimal information on animals and their husbandry. Controlling all major variables as far as possible is the key issue when establishing an experimental design. The other common mechanism affecting study results is a change in the variation. Factors causing bias or variation changes are also detectable within husbandry. Our lives and the lives of animals are governed by cycles: the seasons, the reproductive cycle, the weekend-working days, the cage change/room sanitation cycle, and the diurnal rhythm. Some of these may be attributable to routine husbandry, and the rest are cycles, which may be affected by husbandry procedures. Other issues to be considered are consequences of in-house transport, restrictions caused by caging, randomization of cage location, the physical environment inside the cage, the acoustic environment audible to animals, olfactory environment, materials in the cage, cage complexity, feeding regimens, kinship, and humans. Laboratory animal husbandry issues are an integral but underappreciated part of investigators' experimental design, which if ignored can cause major interference with the results. All researchers should familiarize themselves with the current routine animal care of the facility serving them, including their capabilities for the monitoring of biological and physicochemical environment. PMID:25541541

  20. Experimental approach to neutron stars

    SciTech Connect

    Leifels, Yvonne

    2014-05-09

    The equation of state (EOS) of nuclear matter is of fundamental importance in many areas of nuclear physics and astrophysics In the laboratory, there are different means to study the nuclearmatter equation of state and its density dependence in particular: nuclear masses, neutron skins, pygmy resonance, and nuclear structure at the drip line give access to nuclear matter properties at densities lower than and at saturation density ρ0. Heavy ion reactions at energies above 0.1 AGeV are the only means to study nuclear matter at densities larger than normal nuclear matter density ρ0. In the beamenergy range of 0.1 to 2A GeV nuclear matter is compressed upto three times ρ0. Access to nuclear matter properties is achieved by simulating nuclear collisions by means of microscopic transport codes, or statistical or hydrodynamicalmodels. Characteristics of heavy-ion collisions are discussed, and experimental observables which allow to constrain nuclear matter properties by comparing experimental results with those of transport codes are presented. Special emphasis will be given to the density dependence of the symmetry energy which is the most relevant connection between neutron stars and heavy ion collisions.

  1. SAA drift:experimental results

    NASA Astrophysics Data System (ADS)

    Grigoryan, O. R.; Kudela, K.; Romashova, V. V.; Drozdov, A. Yu.

    According to the paleomagnetic analysis there are variations of Earth's magnetic field connected with magnetic momentum changing. Besides these variations affects on the trapped belt South Atlantic Anomaly (SAA) location. Indeed different observations including Space Shuttle short-time flights approved the existence SAA westward drift with speed 0.1-1.0 (deg/year) and northward drift with speed approximately 0.1 (deg/year). In this work we present the analysis of experimental results obtained in SINP MSU in 1972-2003 from different satellites. There were analyzed the fluxes of protons with energy > 50 MeV, gamma quanta with energy > 500 keV and neutrons with energy 0.1-1.0 MeV in SAA area and their maxima location. The data about fluxes were obtained onboard the orbital stations ``Salut-6'' (1979), MIR (1991, 1998) and ISS (2003) by the identical experimental equipment. The comparison of the data obtained during these two decades of investigations confirms the fact of the SAA westward drift. Moreover the same analysis of maximum flux location of electrons with hundreds keV energy (satellites ``Kosmos-484'' (1972), ``Interkosmos-17'' (1977) and ``Activny'' (``Interkosmos-24'', 1991)) confirmed not only the SAA westward drift but northward drift also.

  2. X-38 Experimental Controls Laws

    NASA Technical Reports Server (NTRS)

    Munday, Steve; Estes, Jay; Bordano, Aldo J.

    2000-01-01

    X-38 Experimental Control Laws X-38 is a NASA JSC/DFRC experimental flight test program developing a series of prototypes for an International Space Station (ISS) Crew Return Vehicle, often called an ISS "lifeboat." X- 38 Vehicle 132 Free Flight 3, currently scheduled for the end of this month, will be the first flight test of a modem FCS architecture called Multi-Application Control-Honeywell (MACH), originally developed by the Honeywell Technology Center. MACH wraps classical P&I outer attitude loops around a modem dynamic inversion attitude rate loop. The dynamic inversion process requires that the flight computer have an onboard aircraft model of expected vehicle dynamics based upon the aerodynamic database. Dynamic inversion is computationally intensive, so some timing modifications were made to implement MACH on the slower flight computers of the subsonic test vehicles. In addition to linear stability margin analyses and high fidelity 6-DOF simulation, hardware-in-the-loop testing is used to verify the implementation of MACH and its robustness to aerodynamic and environmental uncertainties and disturbances.

  3. Experimental Anomalies in Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Palamara, Ornella

    2014-03-01

    In recent years, experimental anomalies ranging in significance (2.8-3.8 σ) have been reported from a variety of experiments studying neutrinos over baselines less than 1 km. Results from the LSND and MiniBooNE short-baseline νe /νe appearance experiments show anomalies which cannot be described by oscillations between the three standard model neutrinos (the ``LSND anomaly''). In addition, a re-analysis of the anti-neutrino flux produced by nuclear power reactors has led to an apparent deficit in νe event rates in a number of reactor experiments (the ``reactor anomaly''). Similarly, calibration runs using 51Cr and 37Ar radioactive sources in the Gallium solar neutrino experiments GALLEX and SAGE have shown an unexplained deficit in the electron neutrino event rate over very short distances (the ``Gallium anomaly''). The puzzling results from these experiments, which together may suggest the existence of physics beyond the Standard Model and hint at exciting new physics, including the possibility of additional low-mass sterile neutrino states, have raised the interest in the community for new experimental efforts that could eventually solve this puzzle. Definitive evidence for sterile neutrinos would be a revolutionary discovery, with implications for particle physics as well as cosmology. Proposals to address these signals by employing accelerator, reactor and radioactive source experiments are in the planning stages or underway worldwide. In this talk some of these will be reviewed, with emphasis on the accelerator programs.

  4. Communications satellites - The experimental years

    NASA Astrophysics Data System (ADS)

    Edelson, B. I.

    1983-10-01

    Only eight years after the launc of Sputnik-1 by the Soviet Union, the first commercial satellite, 'Early Bird', entered service. In just twelve years commercial satellite service extended around the earth and became profitable. The reasons for the successful development of the communications satellite services in a comparatively short time are considered. These reasons are related to the presence of three ingredients, taking into account technology to create the system, communications requirements to form a market, and a management structure to implement the system. The formation of the concept of using earth orbiting satellites for telecommunications is discussed. It is pointed out that the years from 1958 to 1964 were the true 'experimental years' for satellite communications. The rapid development of technology during this crucial period is described, giving attention to passive satellites, active systems, and development satellites.

  5. 'Impulsar': Experimental and Theoretical Investigations

    SciTech Connect

    Apollonov, V. V.

    2008-04-28

    The Objective of the 'Impulsar' project is to accomplish a circle of experimental, engineering and technological works on creation of a high efficiency laser rocket engine. The project includes many organizations of the rocket industry and Academy of Sciences of Russia. High repetition rate pulse-periodic CO{sub 2} laser system project for launching will be presented. Optical system for 15 MW laser energy delivery and optical matrix of laser engine receiver will by discussed as well. Basic characteristics of the laser-based engine will be compared with theoretical predictions and important stages of further technology implementation (low frequency resonance). Relying on a wide cooperation of different branches of science and industry organizations it is very possible to use the accumulated potential for launching of nano-vehicles during the upcoming 4-5 years.

  6. Experimental Investigation of Microstructured Evaporators

    NASA Astrophysics Data System (ADS)

    Wibel, W.; Westermann, S.; Maikowske, S.; Brandner, J. J.

    2012-11-01

    Microfluidic devices have become more and more popular over the last decades [1]. Cooling is a topic where microstructures offer significant advantages compared to conventional techniques due the much higher possible surface to volume ratios and short heat transfer lengths. By evaporating of a fluid in microchannels, compact, fast and powerful cooling devices become possible [2]. Experimental results for different designs of microstructured evaporators are presented here. They have been obtained either using water as evaporating coolant or the refrigerant R134a (Tetrafluoroethane). A new microstructured evaporator design consisting of bended microchannels instead of straight channels for a better performance is shown and compared to previous results [2] for the evaporation of R134a in straight microchannels.

  7. Experimental models of hepatocellular carcinoma☆

    PubMed Central

    Newell, Philippa; Villanueva, Augusto; Friedman, Scott L.; Koike, Kazuhiko; Llovet, Josep M.

    2010-01-01

    Hepatocellular carcinoma (HCC) is a common and deadly cancer whose pathogenesis is incompletely understood. Comparative genomic studies from human HCC samples have classified HCCs into different molecular subgroups; yet, the unifying feature of this tumor is its propensity to arise upon a background of inflammation and fibrosis. This review seeks to analyze the available experimental models in HCC research and to correlate data from human populations with them in order to consolidate our efforts to date, as it is increasingly clear that different models will be required to mimic different subclasses of the neoplasm. These models will be instrumental in the evaluation of compounds targeting specific molecular pathways in future preclinical studies. PMID:18314222

  8. Sexually antagonistic genes: experimental evidence.

    PubMed

    Rice, W R

    1992-06-01

    When selection differs between the sexes, a mutation beneficial to one sex may be harmful to the other (sexually antagonistic). Because the sexes share a common gene pool, selection in one sex can interfere with the other's adaptive evolution. Theory predicts that sexually antagonistic mutations should accumulate in tight linkage with a new sex-determining gene, even when the harm to benefit ratio is high. Genetic markers and artificial selection were used to make a pair of autosomal genes segregate like a new pair of sex-determining genes in a Drosophila melanogaster model system. A 29-generation study provides experimental evidence that sexually antagonistic genes may be common in nature and will accumulate in response to a new sex-determining gene. PMID:1604317

  9. An experimental superconducting helical undulator

    SciTech Connect

    Caspi, S.; Taylor, C.

    1995-12-31

    Improvements in the technology of superconducting magnets for high energy physics and recent advancements in SC materials with the artificial pinning centers (APC){sup 2}, have made a bifilar helical SC device an attractive candidate for a single-pass free electron laser (FEL){sup 3}. Initial studies have suggested that a 6.5 mm inner diameter helical device, with a 27 mm period, can generate a central field of 2-2.5 Tesla. Additional studies have also suggested that with a stored energy of 300 J/m, such a device can be made self-protecting in the event of a quench. However, since the most critical area associated with high current density SC magnets is connected with quenching and training, a short experimental device will have to be built and tested. In this paper we discuss technical issues relevant to the construction of such a device, including a conceptual design, fields, and forces.

  10. Experimental Tests of Special Relativity

    SciTech Connect

    Roberts, Tom

    2006-12-13

    Over the past century Special Relativity has become a cornerstone of modern physics, and its Lorentz invariance is a foundation of every current fundamental theory of physics. So it is crucial that it be thoroughly tested experimentally. The many tests of SR will be discussed, including several modern high-precision measurements. Several experiments that appear to be in conflict with SR will also be discussed, such as claims that the famous measurements of Michelson and Morley actually have a non-null result, and the similar but far more extensive measurements of Dayton Miller that 'determined the absolute motion of the earth'. But the errorbars for these old experiments are huge, and are larger than their purported signals. In short, SR has been tested extremely well and stands un-refuted today, but current thoughts about quantum gravity suggest that it might not truly be a symmetry of nature.

  11. Experimental modeling of pulmonary barotrauma.

    PubMed

    Siermontowski, Piotr; Kozłowski, Wojciech; Pedrycz, Agnieszka; Krefft, Karolina; Kaczerska, Dorota

    2015-01-01

    The main causes of pulmonary barotrauma include loss of consciousness or panic attack of a diver and emergence from underwater with a constricted glottis. However, numerous publications and our observations indicate that the majority of fully symptomatic cases of pulmonary barotrauma develop without any evident errors in the ascending technique. Therefore, an attempt was made to examine such cases using the experimental model of pulmonary barotrauma designed by the authors. The experiment was conducted on 32 rabbits divided into three groups: Group C--not subjected to any treatment; Group E--with induced pulmonary barotrauma; and Group CT--subjected only to compression followed by quick decompression. In Groups E and CT, the same morphological markers of pulmonary barotrauma were detected in the lungs, although their severity varied. Morphological markers of pulmonary barotrauma were observed both in the group where the tube was not ob-structed (E) and in animals exposed only to rapid decompression (CT) PMID:26094289

  12. Ten Problems in Experimental Mathematics

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.; Kapoor, Vishaal; Weisstein, Eric

    2004-09-30

    This article was stimulated by the recent SIAM ''100 DigitChallenge'' of Nick Trefethen, beautifully described in a recent book. Indeed, these ten numeric challenge problems are also listed in a recent book by two of present authors, where they are followed by the ten symbolic/numeric challenge problems that are discussed in this article. Our intent was to present ten problems that are characteristic of the sorts of problems that commonly arise in ''experimental mathematics''. The challenge in each case is to obtain a high precision numeric evaluation of the quantity, and then, if possible, to obtain a symbolic answer, ideally one with proof. Our goal in this article is to provide solutions to these ten problems, and in the process present a concise account of how one combines symbolic and numeric computation, which may be termed ''hybrid computation'', in the process of mathematical discovery.

  13. α-Synuclein: Experimental Pathology.

    PubMed

    Hasegawa, Masato; Nonaka, Takashi; Masuda-Suzukake, Masami

    2016-01-01

    α-Synuclein, which is present as a small, soluble, cytosolic protein in healthy subjects, is converted to amyloid-like fibrils in diseases such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Bulk synthesis of purified α-synuclein has made it more convenient to study the nature of the normal protein and the mechanism of its conversion to an abnormal form in vitro and in vivo. Synthetic α-synuclein fibrils and pathological α-synuclein from diseased brains can act as triggers to convert normal α-synuclein to an abnormal form via prion-like mechanisms. In this article, we describe the experimental pathologies of α-synuclein both in vitro and in vivo in human and animal models. Prion-like spreading of abnormal α-synuclein from cell to cell can account for the progression of these α-synucleinopathies. PMID:27481772

  14. Experimental computation with oscillatory integrals

    SciTech Connect

    Bailey, David H.; Borwein, Jonathan M.

    2009-06-26

    A previous study by one of the present authors, together with D. Borwein and I. Leonard [8], studied the asymptotic behavior of the p-norm of the sinc function: sinc(x) = (sin x)/x and along the way looked at closed forms for integer values of p. In this study we address these integrals with the tools of experimental mathematics, namely by computing their numerical values to high precision, both as a challenge in itself, and also in an attempt to recognize the numerical values as closed-form constants. With this approach, we are able to reproduce several of the results of [8] and to find new results, both numeric and analytic, that go beyond the previous study.

  15. Experimental strategies for frost analysis

    NASA Astrophysics Data System (ADS)

    Janssen, Daniel D.

    An area of increasing importance in the field of refrigeration is the study of frosting and defrosting. Frosting poses a concern to many refrigeration systems, as frost growth both obstructs airflow through low temperature heat exchangers and increases heat transfer resistance. Drastic decreases in system efficiency result from the compounding of these problems, and because it is difficult to prevent the frosting process, refrigeration systems must be defrosted periodically to restore optimal operating conditions. A deeper understanding of the complex physical processes of frosting and defrosting will lead to more efficient refrigeration system designs; an idea which has driven a rise in frost growth research over recent decades. Although research has shown great progress, there remain significant challenges associated with predicting the frosting and defrosting processes accurately under wide ranges of conditions. The equations governing such behavior still remain insoluble by exact analytical methods. Numerical approaches have shown the most promising results, but are yet in an early stage of development. Most research has instead been concerned with developing correlations for frost properties and growth, though few are applicable to varying conditions. The most commonly used correlations are shown to have widely different results, perhaps owing to different experimental methods used to acquire data and a lack of deeper level analysis. A new thickness correlation is proposed which attempts to reconcile to some degree the gap between theory and application. Broader ranges of data are used for fitment which enables the application of the correlation to a wider range of conditions. To improve the consistency of results in frost research, it is suggested that new forms of data acquisition be explored. Proposed alternative methods utilize high magnification imaging equipment in combination with computer based measurements, which are shown to be capable of improving

  16. Experimental models of liver fibrosis.

    PubMed

    Crespo Yanguas, Sara; Cogliati, Bruno; Willebrords, Joost; Maes, Michaël; Colle, Isabelle; van den Bossche, Bert; de Oliveira, Claudia Pinto Marques Souza; Andraus, Wellington; Alves, Venâncio Avancini; Leclercq, Isabelle; Vinken, Mathieu

    2016-05-01

    Hepatic fibrosis is a wound healing response to insults and as such affects the entire world population. In industrialized countries, the main causes of liver fibrosis include alcohol abuse, chronic hepatitis virus infection and non-alcoholic steatohepatitis. A central event in liver fibrosis is the activation of hepatic stellate cells, which is triggered by a plethora of signaling pathways. Liver fibrosis can progress into more severe stages, known as cirrhosis, when liver acini are substituted by nodules, and further to hepatocellular carcinoma. Considerable efforts are currently devoted to liver fibrosis research, not only with the goal of further elucidating the molecular mechanisms that drive this disease, but equally in view of establishing effective diagnostic and therapeutic strategies. The present paper provides a state-of-the-art overview of in vivo and in vitro models used in the field of experimental liver fibrosis research. PMID:26047667

  17. Experimental models of liver fibrosis

    PubMed Central

    Willebrords, Joost; Maes, Michaël; Colle, Isabelle; van den Bossche, Bert; de Oliveira, Claudia Pinto Marques Souza; Andraus, Wellington; Alves, Venâncio Avancini Ferreira; Leclercq, Isabelle; Vinken, Mathieu

    2015-01-01

    Hepatic fibrosis is a wound healing response to insults and as such affects the entire world population. In industrialized countries, the main causes of liver fibrosis include alcohol abuse, chronic hepatitis virus infection and non-alcoholic steatohepatitis. A central event in liver fibrosis is the activation of hepatic stellate cells, which is triggered by a plethora of signaling pathways. Liver fibrosis can progress into more severe stages, known as cirrhosis, when liver acini are substituted by nodules, and further to hepatocellular carcinoma. Considerable efforts are currently devoted to liver fibrosis research, not only with the goal of further elucidating the molecular mechanisms that drive this disease, but equally in view of establishing effective diagnostic and therapeutic strategies. The present paper provides a state-of-the-art overview of in vivo and in vitro models used in the field of experimental liver fibrosis research. PMID:26047667

  18. Experimental studies with palygorskite dusts.

    PubMed

    Wagner, J C; Griffiths, D M; Munday, D E

    1987-11-01

    As the preliminary results of experimental studies on dust from the palygorskite group have led to some confusion a detailed description of the completed investigation is given for clarification. As in other experiments the biological effects have been shown to be associated with the physical characteristics of the fibres in these specimens. Samples of sepiolite and attapulgite from Spain and a single sample of palygorskite from the United Kingdom have been studied. Serious abnormalities were produced only by the palygorskite and one of the attapulgite dusts. The palygorskite is of no commercial interest and the attapulgite was from one small deposit and was used only in the preparation of drilling mud in the exploration of oil deposits. PMID:2961365

  19. Communications satellites - The experimental years

    NASA Technical Reports Server (NTRS)

    Edelson, B. I.

    1983-01-01

    Only eight years after the launc of Sputnik-1 by the Soviet Union, the first commercial satellite, 'Early Bird', entered service. In just twelve years commercial satellite service extended around the earth and became profitable. The reasons for the successful development of the communications satellite services in a comparatively short time are considered. These reasons are related to the presence of three ingredients, taking into account technology to create the system, communications requirements to form a market, and a management structure to implement the system. The formation of the concept of using earth orbiting satellites for telecommunications is discussed. It is pointed out that the years from 1958 to 1964 were the true 'experimental years' for satellite communications. The rapid development of technology during this crucial period is described, giving attention to passive satellites, active systems, and development satellites.

  20. Experimental cochlear hydrops in cats.

    PubMed

    Eby, T L

    1986-11-01

    An experimental model of cochlear hydrops was created in cats. Ten cats underwent surgical procedures to obliterate the saccule, and their temporal bones were studied by light microscopy after sacrifice at 10 weeks. In one group the saccules were destroyed by maceration and aspiration. However, in these ears the saccular lumens were not obliterated and endolymphatic hydrops did not develop. Obliteration of the saccules was achieved in the second group after fascia was introduced into the area of the injured saccules. Cochlear endolymphatic hydrops was a consistent finding in these ears except when a fistula of the membranous labyrinth was present. However, in addition to fibrosis and new bone formation in the vestibules there were also degenerative changes in the hair cells, tectorial membranes, and striae vasculares of these cochleae. The results supported the longitudinal flow theory of endolymph and are consistent with the reported examples of cochlear endolymphatic hydrops in man. PMID:3812642

  1. Automatic Sequencing for Experimental Protocols

    NASA Astrophysics Data System (ADS)

    Hsieh, Paul F.; Stern, Ivan

    We present a paradigm and implementation of a system for the specification of the experimental protocols to be used for the calibration of AXAF mirrors. For the mirror calibration, several thousand individual measurements need to be defined. For each measurement, over one hundred parameters need to be tabulated for the facility test conductor and several hundred instrument parameters need to be set. We provide a high level protocol language which allows for a tractable representation of the measurement protocol. We present a procedure dispatcher which automatically sequences a protocol more accurately and more rapidly than is possible by an unassisted human operator. We also present back-end tools to generate printed procedure manuals and database tables required for review by the AXAF program. This paradigm has been tested and refined in the calibration of detectors to be used in mirror calibration.

  2. Overview of Experimental Capabilities - Supersonics

    NASA Technical Reports Server (NTRS)

    Banks, Daniel W.

    2007-01-01

    This viewgraph presentation gives an overview of experimental capabilities applicable to the area of supersonic research. The contents include: 1) EC Objectives; 2) SUP.11: Elements; 3) NRA; 4) Advanced Flight Simulator Flexible Aircraft Simulation Studies; 5) Advanced Flight Simulator Flying Qualities Guideline Development for Flexible Supersonic Transport Aircraft; 6) Advanced Flight Simulator Rigid/Flex Flight Control; 7) Advanced Flight Simulator Rapid Sim Model Exchange; 8) Flight Test Capabilities Advanced In-Flight Infrared (IR) Thermography; 9) Flight Test Capabilities In-Flight Schlieren; 10) Flight Test Capabilities CLIP Flow Calibration; 11) Flight Test Capabilities PFTF Flowfield Survey; 12) Ground Test Capabilities Laser-Induced Thermal Acoustics (LITA); 13) Ground Test Capabilities Doppler Global Velocimetry (DGV); 14) Ground Test Capabilities Doppler Global Velocimetry (DGV); and 15) Ground Test Capabilities EDL Optical Measurement Capability (PIV) for Rigid/Flexible Decelerator Models.

  3. Compound chondrules: an experimental investigation

    NASA Astrophysics Data System (ADS)

    Connolly, H. C., Jr.; Hewins, R. H.; Atre, N.; Lofgren, G. E.

    1994-07-01

    Compound chondrules are considered to be the product of collisions between molten chondrules during chondrule formation Wasson, J. T. et al. (1994) have argued that some compound chondrules are formed when a chondrule with an accretional rim experienced a flash-melting event similar to a chondrule-forming event. We have designed experiments to investigate the formation of compound chondrules by both methods. Experiments were performed on a Deltech vertical muffle tube furnace to form synthetic chondrules to use as accretion rim material. For our experimental conditions, it is clear that compound chondrules can only be made by a collisional event. Our changes maintain their spherical shape and produce distinct boundaries between charges that are similar to natural compound chondrules. Furthermore, collision event(s) between chondrules will cause nucleation if they are molten and undercooled, thus producing chondrule textures. Flash melting chondrules with accretionary rims will not produce compound chondrules but will produce new chondrules with new textures.

  4. Experimental Tests of Special Relativity

    ScienceCinema

    Roberts, Tom [Illinois Institute of Technology, Chicago, Illinois, United States

    2009-09-01

    Over the past century Special Relativity has become a cornerstone of modern physics, and its Lorentz invariance is a foundation of every current fundamental theory of physics. So it is crucial that it be thoroughly tested experimentally. The many tests of SR will be discussed, including several modern high-precision measurements. Several experiments that appear to be in conflict with SR will also be discussed, such as claims that the famous measurements of Michelson and Morley actually have a non-null result, and the similar but far more extensive measurements of Dayton Miller that 'determined the absolute motion of the earth'. But the errorbars for these old experiments are huge, and are larger than their purported signals. In short, SR has been tested extremely well and stands un-refuted today, but current thoughts about quantum gravity suggest that it might not truly be a symmetry of nature.

  5. Interactive robots in experimental biology.

    PubMed

    Krause, Jens; Winfield, Alan F T; Deneubourg, Jean-Louis

    2011-07-01

    Interactive robots have the potential to revolutionise the study of social behaviour because they provide several methodological advances. In interactions with live animals, the behaviour of robots can be standardised, morphology and behaviour can be decoupled (so that different morphologies and behavioural strategies can be combined), behaviour can be manipulated in complex interaction sequences and models of behaviour can be embodied by the robot and thereby be tested. Furthermore, robots can be used as demonstrators in experiments on social learning. As we discuss here, the opportunities that robots create for new experimental approaches have far-reaching consequences for research in fields such as mate choice, cooperation, social learning, personality studies and collective behaviour. PMID:21496942

  6. Experimental models of hepatocellular carcinoma.

    PubMed

    Newell, Philippa; Villanueva, Augusto; Friedman, Scott L; Koike, Kazuhiko; Llovet, Josep M

    2008-05-01

    Hepatocellular carcinoma (HCC) is a common and deadly cancer whose pathogenesis is incompletely understood. Comparative genomic studies from human HCC samples have classified HCCs into different molecular subgroups; yet, the unifying feature of this tumor is its propensity to arise upon a background of inflammation and fibrosis. This review seeks to analyze the available experimental models in HCC research and to correlate data from human populations with them in order to consolidate our efforts to date, as it is increasingly clear that different models will be required to mimic different subclasses of the neoplasm. These models will be instrumental in the evaluation of compounds targeting specific molecular pathways in future preclinical studies. PMID:18314222

  7. Experimental Internet Environment Software Development

    NASA Technical Reports Server (NTRS)

    Maddux, Gary A.

    1998-01-01

    Geographically distributed project teams need an Internet based collaborative work environment or "Intranet." The Virtual Research Center (VRC) is an experimental Intranet server that combines several services such as desktop conferencing, file archives, on-line publishing, and security. Using the World Wide Web (WWW) as a shared space paradigm, the Graphical User Interface (GUI) presents users with images of a lunar colony. Each project has a wing of the colony and each wing has a conference room, library, laboratory, and mail station. In FY95, the VRC development team proved the feasibility of this shared space concept by building a prototype using a Netscape commerce server and several public domain programs. Successful demonstrations of the prototype resulted in approval for a second phase. Phase 2, documented by this report, will produce a seamlessly integrated environment by introducing new technologies such as Java and Adobe Web Links to replace less efficient interface software.

  8. Experimental subjects are not different

    PubMed Central

    Exadaktylos, Filippos; Espín, Antonio M.; Brañas-Garza, Pablo

    2013-01-01

    Experiments using economic games are becoming a major source for the study of human social behavior. These experiments are usually conducted with university students who voluntarily choose to participate. Across the natural and social sciences, there is some concern about how this “particular” subject pool may systematically produce biased results. Focusing on social preferences, this study employs data from a survey-experiment conducted with a representative sample of a city's population (N = 765). We report behavioral data from five experimental decisions in three canonical games: dictator, ultimatum and trust games. The dataset includes students and non-students as well as volunteers and non-volunteers. We separately examine the effects of being a student and being a volunteer on behavior, which allows a ceteris paribus comparison between self-selected students (students*volunteers) and the representative population. Our results suggest that self-selected students are an appropriate subject pool for the study of social behavior. PMID:23429162

  9. The ethics of animal experimentation.

    PubMed Central

    Lane-Petter, W.

    1976-01-01

    Animal experimentation arouses great emotion in many people, perhaps more especially in Britain, and this has increased as more sophisticated medical and non-medical animal experiments are demanded by modern research. The Cruelty to Animals Act of 1876 is the only legal regulation of experiments in animals, and many of its clauses are ambiguous. So in 1963 a committee of enquiry - the Littlewood Committee - was set up. Dr Lane-Petter examines the emotional and factual background to the enquiry, and discusses in an ethical context the usefulness and positive advantages of animal experiments compared with those of possible substitutes and in some detail three of the questions left unanswered by the Littlewood Committee. PMID:966259

  10. Experimental subjects are not different.

    PubMed

    Exadaktylos, Filippos; Espín, Antonio M; Brañas-Garza, Pablo

    2013-01-01

    Experiments using economic games are becoming a major source for the study of human social behavior. These experiments are usually conducted with university students who voluntarily choose to participate. Across the natural and social sciences, there is some concern about how this "particular" subject pool may systematically produce biased results. Focusing on social preferences, this study employs data from a survey-experiment conducted with a representative sample of a city's population (N = 765). We report behavioral data from five experimental decisions in three canonical games: dictator, ultimatum and trust games. The dataset includes students and non-students as well as volunteers and non-volunteers. We separately examine the effects of being a student and being a volunteer on behavior, which allows a ceteris paribus comparison between self-selected students (students*volunteers) and the representative population. Our results suggest that self-selected students are an appropriate subject pool for the study of social behavior. PMID:23429162

  11. Disposal phase experimental program plan

    SciTech Connect

    1997-01-31

    The Waste Isolation Pilot Plant (WIPP) facility comprises surface and subsurface facilities, including a repository mined in a bedded salt formation at a depth of 2,150 feet. It has been developed to safely and permanently isolate transuranic (TRU) radioactive wastes in a deep geological disposal site. On April 12, 1996, the DOE submitted a revised Resource Conservation and Recovery Act (RCRA) Part B permit application to the New Mexico Environment Department (NMED). The DOE anticipates receiving an operating permit from the NMED; this permit is required prior to the start of disposal operations. On October 29, 1996, the DOE submitted a Compliance Certification Application (CCA) to the US Environmental Protection Agency (EPA) in accordance with the WIPP land Withdrawal Act (LWA) of 1992 (Public Law 102-579) as amended, and the requirements of Title 40 of the Code of Federal Regulations (40 CFR) Parts 191 and 194. The DOE plans to begin disposal operations at the WIPP in November 1997 following receipt of certification by the EPA. The disposal phase is expected to last for 35 years, and will include recertification activities no less than once every five years. This Disposal Phase Experimental Program (DPEP) Plan outlines the experimental program to be conducted during the first 5-year recertification period. It also forms the basis for longer-term activities to be carried out throughout the 35-year disposal phase. Once the WIPP has been shown to be in compliance with regulatory requirements, the disposal phase gives an opportunity to affirm the compliance status of the WIPP, enhance the operations of the WIPP and the national TRU system, and contribute to the resolution of national and international nuclear waste management technical needs. The WIPP is the first facility of its kind in the world. As such, it provides a unique opportunity to advance the technical state of the art for permanent disposal of long-lived radioactive wastes.

  12. Anatabine ameliorates experimental autoimmune thyroiditis.

    PubMed

    Caturegli, Patrizio; De Remigis, Alessandra; Ferlito, Marcella; Landek-Salgado, Melissa A; Iwama, Shintaro; Tzou, Shey-Cherng; Ladenson, Paul W

    2012-09-01

    Tobacco smoking favorably influences the course of Hashimoto thyroiditis, possibly through the antiinflammatory proprieties of nicotine. In this study we tested anatabine, another tobacco alkaloid, in a model of experimental autoimmune thyroiditis. Experimental autoimmune thyroiditis was induced by different doses of thyroglobulin, to produce a disease of low, moderate, or high severity, in 88 CBA/J female mice: 43 drank anatabine supplemented water and 45 regular water. Mice were bled after immunization and killed to assess thyroid histopathology, thyroglobulin antibodies, T(4), and thyroid RNA expression of 84 inflammatory genes. We also stimulated in vitro a macrophage cell line with interferon-γ or lipopolysaccharide plus or minus anatabine to quantitate inducible nitric oxide synthase and cyclooxygenase 2 protein expression. Anatabine reduced the incidence and severity of thyroiditis in the moderate disease category: only 13 of 21 mice (62%) developed thyroid infiltrates when drinking anatabine as compared with 22 of 23 (96%) controls (relative risk 0.59, P = 0.0174). The median thyroiditis severity was 0.5 and 2.0 in anatabine and controls, respectively (P = 0.0007 by Wilcoxon rank sum test). Anatabine also reduced the antibody response to thyroglobulin on d 14 (P = 0.029) and d 21 (P = 0.045) after immunization and improved the recovery of thyroid function on d 21 (P = 0.049). In the thyroid transcriptome, anatabine restored expression of IL-18 and IL-1 receptor type 2 to preimmunization levels. Finally, anatabine suppressed in a dose-dependent manner macrophage production of inducible nitric oxide synthase and cyclooxygenase 2. Anatabine ameliorates disease in a model of autoimmune thyroiditis, making the delineation of its mechanisms of action and potential clinical utility worthwhile. PMID:22807490

  13. A study of non-elastic reaction rates for the ADS materials in the environment of spallation neutrons produced by 1.6 GeV d-beam.

    PubMed

    Bhatia, Chitra; Adam, J; Kumar, V; Katovsky, K; Majerle, M; Solnyshkin, A A; Tsoupko-Sitnikov, V M

    2012-07-01

    For the design and modeling of Accelerator Driven sub-critical System (ADS) a detailed study of response of ADS materials to the spallation neutrons is required. For this purpose reaction rates of different reactions like (n, xn) and (n, xnyp) in 209Bi, natMo, 56Fe, natNi, 55Mn, natTi and natCo materials are determined in an experiment conducted at Nuclotron of JINR, Dubna, using 1.6 GeV d-beam in the 'Energy+Transmutation' set-up. Reaction rates of various (n, xn) and (n, xnyp) reactions are studied in these samples. Results of reaction rates deduced from all the gamma peaks observed in case of 209Bi (n, xn) reactions with x=3-9, natMo (n, γ), (n, 3n), (n, 6n), 56Fe (n, p), (n, p2n), (n, p4n), natNi (n, 2n), (n, 3n), (n, p), (n, d), (n, t), 55Mn (n, γ), (n, 2n), (n, 4n), natTi (n, p), (n, d), (n, t) and natCo (n, γ), (n, xn) reactions with x=2-5 along with (n, p), (n, 2p2n), (n, 2p4n) and (n, 2p6n) are presented. The measured reaction rates for all the elements show good consistency for all the reaction channels and all observed Eγ's of the product nucleus. For all the above mentioned reactions, both experimental as well as theoretical spectrum average cross-sections (σsp.av.cs) are deduced and compared. A close agreement is found between the experimental σsp.av.cs and theoretical σsp.av.cs values. PMID:22204785

  14. Experimental "evolutional machines": mathematical and experimental modeling of biological evolution

    NASA Astrophysics Data System (ADS)

    Brilkov, A. V.; Loginov, I. A.; Morozova, E. V.; Shuvaev, A. N.; Pechurkin, N. S.

    Experimentalists possess model systems of two major types for study of evolution continuous cultivation in the chemostat and long-term development in closed laboratory microecosystems with several trophic structure If evolutionary changes or transfer from one steady state to another in the result of changing qualitative properties of the system take place in such systems the main characteristics of these evolution steps can be measured By now this has not been realized from the point of view of methodology though a lot of data on the work of both types of evolutionary machines has been collected In our experiments with long-term continuous cultivation we used the bacterial strains containing in plasmids the cloned genes of bioluminescence and green fluorescent protein which expression level can be easily changed and controlled In spite of the apparent kinetic diversity of evolutionary transfers in two types of systems the general mechanisms characterizing the increase of used energy flow by populations of primer producent can be revealed at their study According to the energy approach at spontaneous transfer from one steady state to another e g in the process of microevolution competition or selection heat dissipation characterizing the rate of entropy growth should increase rather then decrease or maintain steady as usually believed The results of our observations of experimental evolution require further development of thermodynamic theory of open and closed biological systems and further study of general mechanisms of biological

  15. Experimental Drug for Rheumatoid Arthritis Shows Promise

    MedlinePlus

    ... news/fullstory_158076.html Experimental Drug for Rheumatoid Arthritis Shows Promise Baricitinib helped patients who failed other ... HealthDay News) -- An experimental drug to treat rheumatoid arthritis showed promise in a new six-month trial. ...

  16. Experimental Genital Herpes Drug Shows Promise

    MedlinePlus

    ... gov/medlineplus/news/fullstory_159462.html Experimental Genital Herpes Drug Shows Promise Drug lowered viral activity, recurrence ... News) -- An experimental immune-boosting treatment for genital herpes shows promise, researchers report. The drug, called GEN- ...

  17. The 1986 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Thomas, Lawrence R. (Editor); Mosier, Frances L. (Editor)

    1987-01-01

    The 1986 Get Away Special (GAS) Experimenter's Symposium will provide a formal opportunity for GAS Experimenter's to share the results of their projects. The focus of this symposium is on payloads that will be flown in the future.

  18. Control design for the SERC experimental testbeds

    NASA Technical Reports Server (NTRS)

    Jacques, Robert; Blackwood, Gary; Macmartin, Douglas G.; How, Jonathan; Anderson, Eric

    1992-01-01

    Viewgraphs on control design for the Space Engineering Research Center experimental testbeds are presented. Topics covered include: SISO control design and results; sensor and actuator location; model identification; control design; experimental results; preliminary LAC experimental results; active vibration isolation problem statement; base flexibility coupling into isolation feedback loop; cantilever beam testbed; and closed loop results.

  19. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Experimental certificates. 21.191 Section... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Airworthiness Certificates § 21.191 Experimental certificates. Experimental certificates are issued for the following purposes: (a) Research and development. Testing...

  20. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Experimental certificates. 21.191 Section... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Airworthiness Certificates § 21.191 Experimental certificates. Experimental certificates are issued for the following purposes: (a) Research and development. Testing...

  1. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Experimental wine. 24.77... Experimental wine. (a) General. Any scientific university, college of learning, or institution of scientific research may, without payment of tax, produce, receive, blend, treat, and store wine for experimental...

  2. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Experimental certificates. 21.191 Section... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Airworthiness Certificates § 21.191 Experimental certificates. Experimental certificates are issued for the following purposes: (a) Research and development. Testing...

  3. 27 CFR 24.77 - Experimental wine.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Experimental wine. 24.77... Experimental wine. (a) General. Any scientific university, college of learning, or institution of scientific research may, without payment of tax, produce, receive, blend, treat, and store wine for experimental...

  4. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Experimental certificates. 21.191 Section... CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Airworthiness Certificates § 21.191 Experimental certificates. Experimental certificates are issued for the following purposes: (a) Research and development. Testing...

  5. Experimental constraints on ureilite petrogenesis

    NASA Astrophysics Data System (ADS)

    Singletary, Steven; Grove, Timothy L.

    2006-03-01

    This experimental study explores the petrogenesis of ureilites by a partial melting/smelting process. Experiments have been performed over temperature (1150-1280 °C), pressure (5-12.5 MPa), and low oxygen fugacity (graphite-CO gas) conditions appropriate for a hypothetical ureilite parent body ˜200 km in size. Experimental and modeling results indicate that a partial melting/smelting model of ureilite petrogenesis can explain many of the unique characteristics displayed by this meteorite group. Compositional information preserved in the pigeonite-olivine ureilites was used to estimate the composition of melts in equilibrium with the ureilites. The results of 20 experiments saturated with olivine, pyroxene, metal, and liquid with appropriate ureilite compositions are used to calibrate the phase coefficients and pressure-temperature dependence of the smelting reaction. The calibrated coefficients are used to model the behavior of a hypothetical residue that is experiencing fractional smelting. The residue is initially olivine-rich and smelting progressively depletes the olivine content and enriches the pyroxene and metal contents of the residues. The modeled residue composition at 1260 °C best reproduces the trend of ureilite bulk compositions. The model results also indicate that as a ureilite residue undergoes isothermal decompression smelting over a range of temperatures, Ca/Al values and Cr 2O 3 contents are enriched at lower temperatures (below ˜1240 °C) and tend to decrease at higher temperatures. Therefore, fractional smelting can account for the high Ca/Al and Cr 2O 3 wt% values observed in ureilites. We propose that ureilites were generated from an olivine-rich, cpx-bearing residue. Smelting began when the residue was partially melted and contained liquid, olivine, and carbon. These residues experienced varying degrees of fractional smelting to produce the compositional variability observed within the pigeonite-bearing ureilites. Variations in mineral

  6. Experimental Modelling of Debris Flows

    NASA Astrophysics Data System (ADS)

    Paleo Cageao, P.; Turnbull, B.; Bartelt, P.

    2012-04-01

    Debris flows are gravity-driven mass movements typically containing water, sediments, soil and rocks. These elements combine to give a flow complex phenomenology that exhibits characteristics common to diverse geophysical flows from dry granular media (e.g. levee formation) to viscous gravity currents (viscous fingering and surge instabilities). The exceptional speeds and range debris flows can achieve motivate the need for a co-ordinated modelling approach that can provide insight into the key physical processes that dictate the hazard associated with the flows. There has been recent progress in theoretical modelling approaches that capture the details of the multi-component nature of debris flows. The promise of such models is underlined by their qualitatively successful comparison with field-scale experimental data. The aim of the present work is to address the technical difficulties in achieving a controlled and repeatable laboratory-scale experiment for robust testing of these multi-component models. A laboratory experiment has been designed and tested that can provide detailed information of the internal structure of debris flows. This constitutes a narrow Perspex chute that can be tilted to any angle between 0° and ≈ 60°. A mixture of glycerine and glass balls was initially held behind a lock-gate, before being released down the chute. The evolving flow was captured through high speed video, analysed with a Particle Image Velocimetry algorithm to provide the changing velocity field. A wide parameter space has been tested, allowing variations in particle size, dispersity, surface roughness, fluid viscosity, slope angle and solid volume fraction. While matching key similarity criteria, such as Froude number, with a typical field event, these experiments allow close examination of a wide range of physical scenarios for the robust testing of new multi-component flow models. Further diagnostics include force plate and pore pressure measurements, with a view

  7. Experimental Implementations of Quantum Paradoxes

    NASA Astrophysics Data System (ADS)

    Briggs, G. A. D.

    Remarkable progress is being made in experiments that highlight the distinctive predictions of quantum mechanics. The Leggett-Garg inequality was devised to test for macrorealism (Leggett and Garg in Phys. Rev. Lett. 54:857-860, 1985). Various experiments have been performed, including one with non-invasive measurements in the kind of way that was originally envisaged, using spins in phosphorous impurities in silicon (Knee et al. in Nat. Commun. 3:606, 2012). This has led to fresh understanding of what kind of realism is excluded by the result. The quantum three-box paradox (Aharonov and Vaidman in J. Phys. A, Math. Gen. 24:2315-2328, 1991) provides a further test, which can be re-expressed in terms of the Leggett-Garg inequality. This has been experimentally implemented with projective measurements using an NV- centre in diamond, yielding results 7.8 standard deviations beyond a classical bound (George et al. in Proc. Natl. Acad. Sci. USA 110:3777-3781, 2013). [Editor's note: for a video of the talk given by Prof. Briggs at the Aharonov-80 conference in 2012 at Chapman University, see http://quantum.chapman.edu/talk-18.

  8. Micas in experimentally shocked gneiss

    NASA Technical Reports Server (NTRS)

    Lambert, P.; Mackinnon, I. D. R.

    1984-01-01

    Powder-propellant guns are used to shock biotites and muscovites from a gneiss at pressures between 18 and 70 GPa. It is shown that shock in biotite and muscovite can produce homogeneous and devolatilized glasses within microseconds. Shock-deformed micas are found to exhibit fracturing, kinking, and complex extinction patterns over the entire pressure range investigated. Localized melting of micas commences at 33 GPa and reaches completion at 70 GPa. Even though melted biotite and muscovite are opaque optically, they exhibit extensive microvesiculation and flow when observed with the SEM. It is confirmed through electron diffraction that biotite and muscovite have transformed to a glass. The distribution of vesicles in shock-vitrified mica reveals escape of volatiles within the short duration of the shock experiment. It is noted that experimentally shocked biotite and muscovite undergo congruent melting. It is noted that the compositions of the glasses are similar to the unshocked micas except for volatiles (H2O loss and and K loss). These unusual glasses produced from mica can be quenched by rapid cooling conditions during the shock experiment. On the basis of the results, it is pointed out that the extremely low H2O content of tektites can be reconciled with a terrestrial origin by impact.

  9. Experimental research control software system

    NASA Astrophysics Data System (ADS)

    Cohn, I. A.; Kovalenko, A. G.; Vystavkin, A. N.

    2014-05-01

    A software system, intended for automation of a small scale research, has been developed. The software allows one to control equipment, acquire and process data by means of simple scripts. The main purpose of that development is to increase experiment automation easiness, thus significantly reducing experimental setup automation efforts. In particular, minimal programming skills are required and supervisors have no reviewing troubles. Interactions between scripts and equipment are managed automatically, thus allowing to run multiple scripts simultaneously. Unlike well-known data acquisition commercial software systems, the control is performed by an imperative scripting language. This approach eases complex control and data acquisition algorithms implementation. A modular interface library performs interaction with external interfaces. While most widely used interfaces are already implemented, a simple framework is developed for fast implementations of new software and hardware interfaces. While the software is in continuous development with new features being implemented, it is already used in our laboratory for automation of a helium-3 cryostat control and data acquisition. The software is open source and distributed under Gnu Public License.

  10. Experimental Surveys for Submerged Inlet

    NASA Astrophysics Data System (ADS)

    Jovanovic, Vasilije; Taskinoglu, Ezgi; Elliott, Gregory; Knight, Doyle

    2003-11-01

    The objective of the study is to define the Pareto set of designs for a subsonic submerged inlet that minimizes flow distortion and swirl at the engine face. A series of experimental surveys are performed to validate the accompanying computations and to provide additional information regarding the Pareto set. A stainless steel model with a removable submerged inlet (built using an FDM system) has been fabricated and installed in the Rutgers University subsonic wind tunnel. Boundary layer measurements upstream of the inlet are obtained by a computer-controlled traversing pitot tube. The estimated boundary layer thickness agrees closely with the computed profile. Detailed experiments are focused on the measurement of total pressure three diameters downstream of the exit of the inlet. A rotating multi-element pitot rack is fabricated and installed in the model, which is attached to the suction side of a blower to yield the appropriate mass flow rate through the inlet. Motion control, pressure and temperature data acquisition as well as management of the wind tunnel operations for all experiments are controlled by a LabView program developed at Rutgers University.

  11. [HERNIOPLASTIC MORFOLOGICAL FEATURES (EXPERIMENTAL STADY)].

    PubMed

    Gogoladze, M; Kiladze, M; Chkhikvadze, T; Tsivtsivadze, L; Jiqia, D

    2016-05-01

    Despite many years of experience in the field of hernia surgical treatment there still exist many unsolved problems such as a safe and non infected closure of defects of abdominal cavity wall. The aim of the study was to improve the result of treatment of abdominal wall hernias with the use of new antiseptic polymer, bio-composite protective mesh membrane covered with coladerm+chlorhexidine. Experimental study involved 21 rabbits. Meshes were fixed on anterior abdominal wall according to the following schewe: Option I: mesh size 10-20mm was put into both the groin area of the rabbits. Option II: A light standart mesh grid size 10-20mm covered with coladerm was placed on both sides of abdominal wall of the rabbits. Option III: A light mesh, covered with oladerm+Chlorhexidine was placed in to the abdominal wall of the rabbits. Removal dates of taking the animals from experiments were 14th, 30th, 45th, 90th and 180th days for further histomorpological and bacteriological research. The best result from these options was when implants we covered with coladerm+Chlorhexidine, which was shown on follow up period. In third control group experessed strong connective tissue formatting stromis picture,wich is the main task of modern hernia plastic. It is expected that new bio-composite meshes, covered with coladerm+Chlorhexidine, may be succesfuly used in clinical practice, which will reduce infectious complications of meshes and problems associated with them. PMID:27348172

  12. Angiogenesis and experimental hepatic fibrosis.

    PubMed

    Lemos, Queli Teixeira; Andrade, Zilton A

    2010-08-01

    Angiogenesis is a basic change occurring during repair by granulation tissue. This process seems to precede fibrosis formation in most types of chronic liver disease. To examine its presence and significance in different types of hepatic insults, this paper sought to identify the presence, evolution and peculiarities of angiogenesis in the most common experimental models of hepatic fibrosis. The characterization of cells, vessels and extracellular matrix and the identification of factors associated with endothelium (factor VIII RA), vascular basement membrane, other components of the vascular walls (actin, elastin) and the presence of the vascular-endothelial growth factor were investigated. The models examined included Capillaria hepatica septal fibrosis, whole pig serum injections, carbon tetrachloride administration, main bile duct ligation and Schistosoma mansoni infection. The first four models were performed in rats, while the last used mice. All models studied exhibited prominent angiogenesis. The most evident relationship between angiogenesis and fibrosis occurred with the C. hepatica model due to circumstances to be discussed. Special attention was paid to the presence of pericytes and to their tendency to become detached from the vascular wall and be transformed into myofibroblasts, which is a sequence of events that explains the decisive role angiogenesis plays in fibrosis. PMID:20835605

  13. Teaching experimental design to biologists.

    PubMed

    Zolman, J F

    1999-12-01

    The teaching of research design and data analysis to our graduate students has been a persistent problem. A course is described in which students, early in their graduate training, obtain extensive practice in designing experiments and interpreting data. Lecture-discussions on the essentials of biostatistics are given, and then these essentials are repeatedly reviewed by illustrating their applications and misapplications in numerous research design problems. Students critique these designs and prepare similar problems for peer evaluation. In most problems the treatments are confounded by extraneous variables, proper controls may be absent, or data analysis may be incorrect. For each problem, students must decide whether the researchers' conclusions are valid and, if not, must identify a fatal experimental flaw. Students learn that an experiment is a well-conceived plan for data collection, analysis, and interpretation. They enjoy the interactive evaluations of research designs and appreciate the repetitive review of common flaws in different experiments. They also benefit from their practice in scientific writing and in critically evaluating their peers' designs. PMID:10644236

  14. The Experimental MJO Prediction Project

    NASA Technical Reports Server (NTRS)

    Waliser, Duane; Weickmann, Klaus; Dole, Randall; Schubert, Siegfried; Alves, Oscar; Jones, Charles; Newman, Matthew; Pan, Hua-Lu; Roubicek, Andres; Saha, Suranjana; Smith, Cathy; VanDenDool, Huug; Vitart, Frederic; Wheeler, Matthew; Whitaker, Jeffrey

    2006-01-01

    Weather prediction is typically concerned with lead times of hours to days, while seasonal-to-interannual climate prediction is concerned with lead times of months to seasons. Recently, there has been growing interest in 'subseasonal' forecasts---those that have lead times on the order of weeks (e.g., Schubert et al. 2002; Waliser et al. 2003; Waliser et al. 2005). The basis for developing and exploiting subseasonal predictions largely resides with phenomena such as the Pacific North American (PNA) pattern, the North Atlantic oscillation (NAO), the Madden-Julian Oscillation (MJO), mid-latitude blocking, and the memory associated with soil moisture, as well as modeling techniques that rely on both initial conditions and slowly varying boundary conditions (e.g., tropical Pacific SST). An outgrowth of this interest has been the development of an Experimental MJO Prediction Project (EMPP). Th project provides real-time weather and climate information and predictions for a variety of applications, broadly encompassing the subseasonal weather-climate connection. Th focus is on the MJO because it represents a repeatable, low-frequency phenomenon. MJO's importance among the subseasonal phenomena is very similar to that of El Nino-Southern Oscillation(ENSO) among the interannual phenomena. This note describes the history and objectives of EMPP, its status,capabilities, and plans.

  15. Experimental investigation of plasmofluidic waveguides

    SciTech Connect

    Ku, Bonwoo; Kwon, Min-Suk; Shin, Jin-Soo

    2015-11-16

    Plasmofluidic waveguides are based on guiding light which is strongly confined in fluid with the assistance of a surface plasmon polariton. To realize plasmofluidic waveguides, metal-insulator-silicon-insulator-metal (MISIM) waveguides, which are hybrid plasmonic waveguides fabricated using standard complementary metal-oxide-semiconductor technology, are employed. The insulator of the MISIM waveguide is removed to form 30-nm-wide channels, and they are filled with fluid. The plasmofluidic waveguide has a subwavelength-scale mode area since its mode is strongly confined in the fluid. The waveguides are experimentally characterized for different fluids. When the refractive index of the fluid is 1.440, the plasmofluidic waveguide with 190-nm-wide silicon has propagation loss of 0.46 dB/μm; the coupling loss between it and an ordinary silicon photonic waveguide is 1.79 dB. The propagation and coupling losses may be reduced if a few fabrication-induced imperfections are removed. The plasmofluidic waveguide may pave the way to a dynamically phase-tunable ultracompact device.

  16. Experimental investigations of elastohydrodynamic lubrication

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.; Dowson, D.

    1983-01-01

    Various experimental studies of elastohydrodynamic lubrication have been reviewed. The various types of machines used in these investigations, such as the disc, two and four ball, crossed-cylinders, and crossed-axes rolling disc machine, are described. The measurement of the most important parameters, such as film shape, film thickness, pressure, temperature, and traction, is considered. Determination of the film thickness is generally the most important of these effects since it dictates the extent to which the asperities on opposing surfaces can come into contact and thus has a direct bearing on wear and fatigue failure of the contacting surfaces. Several different techniques for measuring film thickness have been described, including electrical resistance, capacitance, X-ray, optical interferometry, laser beam diffraction, strain gage, and spring dynamometer methods. An attempt has been made to describe the basic concepts and limitations of each of these techniques. These various methods have been used by individual researchers, but there is no universally acceptable technique for measuring elastohydrodynamic film thickness. Capacitance methods have provided most of the reliable data for nominal line or rectangular conjunctions, but optical interferometry has proved to be the most effective procedure for elliptical contacts. Optical interferometry has the great advantage that it reveals not only the film thickness, but also details of the film shape over the complete area of the conjunction.

  17. Compendium of Experimental Cetane Numbers

    SciTech Connect

    Yanowitz, J.; Ratcliff, M. A.; McCormick, R. L.; Taylor, J. D.; Murphy, M. J.

    2014-08-01

    This report is an updated version of the 2004 Compendium of Experimental Cetane Number Data and presents a compilation of measured cetane numbers for pure chemical compounds. It includes all available single compound cetane number data found in the scientific literature up until March 2014 as well as a number of unpublished values, most measured over the past decade at the National Renewable Energy Laboratory. This Compendium contains cetane values for 389 pure compounds, including 189 hydrocarbons and 201 oxygenates. More than 250 individual measurements are new to this version of the Compendium. For many compounds, numerous measurements are included, often collected by different researchers using different methods. Cetane number is a relative ranking of a fuel's autoignition characteristics for use in compression ignition engines; it is based on the amount of time between fuel injection and ignition, also known as ignition delay. The cetane number is typically measured either in a single-cylinder engine or a constant volume combustion chamber. Values in the previous Compendium derived from octane numbers have been removed, and replaced with a brief analysis of the correlation between cetane numbers and octane numbers. The discussion on the accuracy and precision of the most commonly used methods for measuring cetane has been expanded and the data has been annotated extensively to provide additional information that will help the reader judge the relative reliability of individual results.

  18. Majorana Thermosyphon Prototype Experimental Results

    SciTech Connect

    Fast, James E.; Reid, Douglas J.; Aguayo Navarrete, Estanislao

    2010-12-17

    Objective The Majorana demonstrator will operate at liquid Nitrogen temperatures to ensure optimal spectrometric performance of its High Purity Germanium (HPGe) detector modules. In order to transfer the heat load of the detector module, the Majorana demonstrator requires a cooling system that will maintain a stable liquid nitrogen temperature. This cooling system is required to transport the heat from the detector chamber outside the shield. One approach is to use the two phase liquid-gas equilibrium to ensure constant temperature. This cooling technique is used in a thermosyphon. The thermosyphon can be designed so the vaporization/condensing process transfers heat through the shield while maintaining a stable operating temperature. A prototype of such system has been built at PNNL. This document presents the experimental results of the prototype and evaluates the heat transfer performance of the system. The cool down time, temperature gradient in the thermosyphon, and heat transfer analysis are studied in this document with different heat load applied to the prototype.

  19. Experimental Quantum Optics with Photons

    NASA Astrophysics Data System (ADS)

    Wu, Ling-An

    2005-10-01

    Our group is engaged primarily in experimental quantum optics and related research involving single photon detection that may have future applications. There are six graduate students involved, of whom three are women. We have recently completed the first successful demonstration of correlated two-photon imaging and sub-wavelength interference with true thermal light from a hollow cathode lamp. The object was a pair of pinholes, and the corresponding thin lens equation was well satisfied. Although the visibility is substantially lower than in the case of entangled photons, it is conceivable that if the background could be removed by some means (e.g., digitally), there could be many applications for correlated imaging with thermal light. We have also built a quantum key distribution system based on two polarization beam splitters that cancel out the phase modulator's polarization dependence. A high key generation rate has been obtained for the first time at 1310 nm transmitted over a 25-km-long fiber, with a fringe visibility of 99.4%. A sifted key rate of about 0.6 kbits/s and quantum bit error rate of about 0.5% have been obtained.

  20. Experimental Studies in Ice Nucleation

    NASA Astrophysics Data System (ADS)

    Wright, Timothy Peter

    Ice nuclei play a critical role in the formation of precipitation in mixed phase clouds. Modification of IN concentrations can lead to changes in cloud lifetimes and precipitation size. Presented in this study are experimental investigations into ice nuclei in an ongoing effort to reduce the uncertainties that ice nuclei have on cloud processes and climate. This research presents a new version of the cold stage drop freezing assay to investigate the time-dependence of heterogeneous nucleation. The temperature range for the instrument spans from the melting point of water to the homogeneous freezing limit of ˜-38 deg C. Temperature stability for the instrument allowed for experimental operation for up to four days while interrogating the same sample. Up to a one hundred fold increase in the number of analyzed drops was accomplished through an in-house written automated drop freezing detection software package. Combined instrument design improvements allow for the analysis of IN concentrations down to ˜10-8 ice nuclei per picoliter of sample water. A new variant of the multiple-component stochastic model for heterogeneous ice nucleation was used to investigate the time dependence of heterogeneous freezing processes. This was accomplished by analyzing how the changes in the cooling rate can impact the observed nucleation rate. The model employed four material-dependent parameters to accurately capture the observed freezing of water drops containing Arizona Test Dust. The parameters were then used to accurately predict the freezing behavior of the drops in time dependent experiments. The time dependence freezing of a wide range of materials was then investigated. These materials included the minerals montmorillonite and kaolinite, the biological proxy ice nuclei contained within the product Icemax, and flame soot generated from the incomplete combustion of ethylene gas. The time dependence for ice nuclei collected from rainwater samples was also investigated. The

  1. [Regeneration of planarians: experimental object].

    PubMed

    Sheĭman, I M; Kreshchenko, I D

    2015-01-01

    We discuss the expediency of using invertebrates, such as flatworms and planarians, as experimental objects. Free-living planarian flatworms (phylum Platyhelminthes, class Turbellaria) are invertebrate animals in which a bilateral symmetry appears for the first time in evolution and organs and tissues form. As the highest ecological link of the food chain--predators--these animals are characterized by a set of behavioral reactions controlled by a differentiated central nervous system. Planarians have unsurpassed ability to regenerate lost or damaged body parts. Owing to the ease of their breeding and their convenience for manipulations, these animals are used to study the influence of chemical and physical factors on the processes of life, growth, and reproduction. Currently, planarians are recognized as a model for biological research in the field of regeneration, stem cell biology, study of their proliferation and differentiation, as well as the regulatory mechanisms of morphogenetic processes. The genome of the planarian Schmidtea mediterranea was fully sequenced, which opened up the opportunity to work with this object at the molecular biological level. Furthermore, planarians are used in neurobiological and toxicological studies, in studying the evolutionary aspects of centralization of the nervous system, mechanisms of muscle contraction, and in the development of new antiparasitic drugs. This review aims to demonstrate the relevance and diversity of research conducted on simple biological objects--planarians--to awider audience to show the historical continuity of these studies and their wide geographical distribution and to focus on the studies carried out in Russia, which, as a rule, are not included in the foreign reviews on planarian regeneration. PMID:25898529

  2. Elementary particle physics---Experimental

    SciTech Connect

    Lord, J.J.; Burnett, T.H.; Wilkes, R.J.

    1990-09-20

    We are continuing a research program in high energy experimental particle physics and particle astrophysics. Studies of high energy hadronic interactions were performed using several techniques, in addition, a high energy leptoproduction experiment was continued at the Fermi National Accelerator Laboratory. We are participants in a joint US/Japan program to study nuclear interactions at energies two orders of magnitude greater than those of existing accelerators. The data are being collected with ballon-borne emulsion chambers. The properties of nuclear interactions at these high energies will reveal whether new production mechanisms come into play due to the high nuclear densities and temperatures obtained. We carried out closely related studies of hadronic interactions in emulsions exposed to high energy accelerator beams. We are members of a large international collaboration which has exposed emulsion chamber detectors to beams of {sup 32}S and {sup 16}O with energy 60 and 200 GeV/n at CERN and 15 GeV/n at Brookhaven National Laboratory. The primary objectives of this program are to determine the existence and properties of the hypothesized quark-gluon phase of matter, and its possible relation to a variety of anomalous observations. Studies of leptoproduction processes at high energies involve two separate experiments, one using the Tevatron 500 GeV muon beam and the other exploring the >TeV regime. We are participants in Fermilab experiment E665 employing a comprehensive counter/streamer chamber detector system. During the past year we joined the DUMAND Collaboration, and have been assigned responsibility for development and construction of critical components for the deep undersea neutrino detector facility, to be deployed in 1991. In addition, we are making significant contributions to the design of the triggering system to be used.

  3. Experimental techniques for multiphase flows

    NASA Astrophysics Data System (ADS)

    Powell, Robert L.

    2008-04-01

    This review discusses experimental techniques that provide an accurate spatial and temporal measurement of the fields used to describe multiphase systems for a wide range of concentrations, velocities, and chemical constituents. Five methods are discussed: magnetic resonance imaging (MRI), ultrasonic pulsed Doppler velocimetry (UPDV), electrical impedance tomography (EIT), x-ray radiography, and neutron radiography. All of the techniques are capable of measuring the distribution of solids in suspensions. The most versatile technique is MRI, which can be used for spatially resolved measurements of concentration, velocity, chemical constituents, and diffusivity. The ability to measure concentration allows for the study of sedimentation and shear-induced migration. One-dimensional and two-dimensional velocity profiles have been measured with suspensions, emulsions, and a range of other complex liquids. Chemical shift MRI can discriminate between different constituents in an emulsion where diffusivity measurements allow the particle size to be determined. UPDV is an alternative technique for velocity measurement. There are some limitations regarding the ability to map complex flow fields as a result of the attenuation of the ultrasonic wave in concentrated systems that have high viscosities or where multiple scattering effects may be present. When combined with measurements of the pressure drop, both MRI and UPDV can provide local values of viscosity in pipe flow. EIT is a low cost means of measuring concentration profiles and has been used to study shear-induced migration in pipe flow. Both x-ray and neutron radiographes are used to image structures in flowing suspensions, but both require highly specialized facilities.

  4. Magnetic Launch Assist Experimental Track

    NASA Technical Reports Server (NTRS)

    1999-01-01

    In this photograph, a futuristic spacecraft model sits atop a carrier on the Magnetic Launch Assist System, formerly known as the Magnetic Levitation (MagLev) System, experimental track at the Marshall Space Flight Center (MSFC). Engineers at MSFC have developed and tested Magnetic Launch Assist technologies that would use magnetic fields to levitate and accelerate a vehicle along a track at very high speeds. Similar to high-speed trains and roller coasters that use high-strength magnets to lift and propel a vehicle a couple of inches above a guideway, a Magnetic Launch Assist system would electromagnetically drive a space vehicle along the track. A full-scale, operational track would be about 1.5-miles long and capable of accelerating a vehicle to 600 mph in 9.5 seconds. This track is an advanced linear induction motor. Induction motors are common in fans, power drills, and sewing machines. Instead of spinning in a circular motion to turn a shaft or gears, a linear induction motor produces thrust in a straight line. Mounted on concrete pedestals, the track is 100-feet long, about 2-feet wide, and about 1.5-feet high. The major advantages of launch assist for NASA launch vehicles is that it reduces the weight of the take-off, the landing gear, the wing size, and less propellant resulting in significant cost savings. The US Navy and the British MOD (Ministry of Defense) are planning to use magnetic launch assist for their next generation aircraft carriers as the aircraft launch system. The US Army is considering using this technology for launching target drones for anti-aircraft training.

  5. Experimental Infrasound Studies in Nevada

    NASA Astrophysics Data System (ADS)

    Herrin, E. T.; Negraru, P. T.; Golden, P.; Williams, A.

    2009-12-01

    An experimental propagation study was carried out in Nevada in June 2009 on Julian days 173-177. During this field experiment we deployed 16 single channel digital infrasound recorders to monitor the munitions disposal activities near Hawthorne, NV. The sensors were deployed in a single line and placed approximately 12 km apart at distances ranging from 2 to 177 km. A four element semi-permanent infrasound array named FNIAR was installed approximately 154 km north of the detonation site in line with the individual temporary recorders. Tropospheric arrivals were observed during all days of the experiment, but during day 176 the observed arrivals had very large amplitudes. A large signal was observed at 58 km from the detonation site with amplitude as large as 4 Pascals, while at 94 km no signal was observed. At FNIAR the amplitude of the tropospheric arrival was 1 Pascal. During this day meteorological data acquired in the propagation path showed a strong jet stream to the north. On day 177 we were not able to identify tropospheric arrivals beyond 34 km, but at stations beyond 152 km we observed stratospheric arrivals. Continuous monitoring of these signals at FNIAR shows that stratospheric arrivals are the most numerous. In a two month period, from 06/15/2009 to 08/15/2009 there were 35 operational days at the Hawthorne disposal facility resulting in 212 explosions with known origin times. Based on the celerity values there were 115 explosions that have only stratospheric arrivals (celerities of 300-275 m/s), 72 explosions with both tropospheric (celerities above 330 m/s) and stratospheric arrivals, 20 explosions that were not detected and five explosions that have only tropospheric arrivals.

  6. Epistemological Dizziness in the Psychology Laboratory: Lively Subjects, Anxious Experimenters, and Experimental Relations, 1950-1970.

    PubMed

    Morawski, Jill

    2015-09-01

    Since the demise of introspective techniques in the early twentieth century, experimental psychology has largely assumed an administrative arrangement between experimenters and subjects wherein subjects respond to experimenters' instructions and experimenters meticulously constrain that relationship through experimental controls. During the postwar era this standard arrangement came to be questioned, initiating reflections that resonated with Cold War anxieties about the nature of the subjects and the experimenters alike. Albeit relatively short lived, these interrogations of laboratory relationships gave rise to unconventional testimonies and critiques of experimental method and epistemology. Researchers voiced serious concerns about the honesty and normality of subjects, the politics of the laboratory, and their own experimental conduct. Their reflective commentaries record the intimacy of subject and experimenter relations and the plentiful cultural materials that constituted the experimental situation, revealing the permeable boundaries between laboratory and everyday life. PMID:26685518

  7. Experimental generation of volcanic lightning

    NASA Astrophysics Data System (ADS)

    Cimarelli, Corrado; Alatorre-Ibargüengoitia, Miguel; Kueppers, Ulrich; Scheu, Bettina; Dingwell, Donald B.

    2014-05-01

    the plume that emerge as the key variables in volcanic lightning generation. A proportionality between fine ash content of the jet and number of lightning strikes is also evident in our experiments. This first recorded experimental generation of volcanic lightning means that rapid progress can now be expected (under controlled laboratory conditions) in understanding electrical phenomena produced during explosive volcanic eruptions. This in turn may aid the development of lightning monitoring systems for the forecasting of volcanic ash emissions into the atmosphere. Furthermore, our experiments are significant for the investigation of self-charging mechanism of particles that are relevant for atmospheric phenomena (such as dust storms) on Earth and other planetary bodies.

  8. Mars Radiator Characterization Experimental Program

    NASA Technical Reports Server (NTRS)

    Witte, Larry C.; Hollingsworth, D. Keith

    2004-01-01

    Radiators are an enabling technology for the human exploration and development of the moon and Mars. As standard components of the heat rejection subsystem of space vehicles, radiators are used to reject waste heat to space and/or a planetary environment. They are typically large components of the thermal control system for a space vehicle or human habitation facility, and in some cases safety factors are used to oversize them when the operating environment cannot be fully characterized. Over-sizing can impose significant weight and size penalties that might be prohibitive for future missions. Radiator performance depends on the size of the radiator surface, its emittance and absorptance, the radiator temperature, the effective sky temperature surrounding the radiator, solar radiation and atmospheric irradiation levels, convection to or from the atmosphere (on Mars), and other conditions that could affect the nature of the radiator surface, such as dust accumulation. Most particularly, dust is expected to be a major contributor to the local environmental conditions on either the lunar or Martian surface. This conclusion regarding Mars is supported by measurements of dust accumulation on the Mars Sojourner Rover solar array during the Pathfinder mission. This Final Report describes a study of the effect of Martian dust accumulation on radiator performance. It is comprised of quantitative measurements of effective emittance for a range of dust accumulation levels on surfaces of known emittance under clean conditions. The test radiator coatings were Z-93P, NS-43G, and Silver Teflon (10 mil) film. The Martian dust simulant was Carbondale Red Clay. Results were obtained under vacuum conditions sufficient to reduce convection effects virtually to zero. The experiments required the development of a calorimetric apparatus that allows simultaneous measurements of the effective emittance for all the coatings at each set of experimental conditions. A method of adding dust to

  9. [Experimental antitriatomic program in Santiago].

    PubMed

    Neghme, A; Schenone, H; Villarroel, F; Rojas, A

    1991-01-01

    The rural migration to urban centers occurred since the 40s in many Latin American countries, including Santiago the capital city of Chile, originated a growing belt of premises built with light poor material (the rests of previous rural habitations, mud, pieces of timber, plastic and cardboard for walls, and cane stalks and artificial clinkstones for roofs) giving raise to many types of slums. This situation facilitated the passive transport of the different instars, including eggs, of triatomine bugs. Due to the fact that in the 1959-1960 warm seasons, the Santiago province health institutions had received an increasing reported number of triatomine bugs (Triatoma infestans) in dwellings from different periurban, even urban and rural sections of the province, the central local health authorities with the advise of the University of Chile, Department of Parasitology decided to carry out an experimental program against these vectors of Chagas' disease. The program consisted basically in an spray and thorough application of liquid forms (emulsion, suspension, solution) of 1% lindane (average > or = 500 mg per 1 m2), depending on the material of the constructions, to all the surfaces of walls, ceilings, attics and peridomiciliary structures of all the infested dwellings in a sector and those located less than 100 m around. In order to reach triatomine bugs not affected, for different reasons, in the first spraying, a second application, identical to the first was performed to the total number of premises between 30 and 120 days later. Periodical evaluations were made, and positive dwellings found and neighboring ones were sprayed again. During insecticide applications adequate protection measures for spraying workers, inhabitants, domestic animals, household goods and food were adopted. All the steps of the program were accompanied by health education activities directed to individuals, families, school teachers and community institutions, tending to motivate the

  10. Experimental reproduction of tsunami deposit

    NASA Astrophysics Data System (ADS)

    Yoshii, T.; Matsuyama, M.; Tanaka, S.

    2015-12-01

    in reproducing tsunami deposit and would show typical pattern of topography change and deposition caused by the tsunami incursion. The experimental method used in this study and the obtained deposition patterns will help understanding the relationship between hydraulic condition and resulting tsunami deposition.

  11. Charge of the containerless experimentation in microgravity

    NASA Technical Reports Server (NTRS)

    Lee, Mark C.

    1990-01-01

    The experimentation was undertaken to study the elimination or reduction of surface contamination for which there is adequate Earth-based technology along with the reduction of dynamic nucleation for which there a paucity of reliable data. One objective is to delineate scientific justification of the U.S. Containerless Experimentation Program in Microgravity for the next decade and beyond. Another objective is for the guidance of NASA to define the next generation of containerless experimentation instruments in microgravity.

  12. Experimental investigation of new neutron moderator materials

    SciTech Connect

    Mocko, Michal; Daemen, Luke L; Hartl, Monika; Huegle, Thomas; Muhrer, Guenter

    2010-01-01

    In this study we present experimental investigation of thermal neutron energy spectra produced by lead and bismuth hydroxides (Pb(OH){sub 2}, and Bi(OH){sub 3}). The experimental energy spectra are compared with a thermal neutron energy spectrum of water measured in the same geometry. We present an MCNPX geometry model used to help with the experimental data interpretation. We demonstrate a very good reproduction of the experimental thermal neutron energy spectrum produced by the water moderator. We show a sensitivity study with the Pb(OH){sub 2}, and Bi(OH){sub 3} materials on different combinations of thermal neutron scattering kernels.

  13. 50 CFR 648.12 - Experimental fishing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... red crab), N (tilefish), and O (skates) of this part for the conduct of experimental fishing... international accreditation body); international treaty organization; or scientific institution. (3)...

  14. 50 CFR 648.12 - Experimental fishing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... red crab), N (tilefish), and O (skates) of this part for the conduct of experimental fishing... international accreditation body); international treaty organization; or scientific institution. (3)...

  15. Experimental methods for identifying failure mechanisms

    NASA Technical Reports Server (NTRS)

    Daniel, I. M.

    1983-01-01

    Experimental methods for identifying failure mechanisms in fibrous composites are studied. Methods to identify failure in composite materials includes interferometry, holography, fractography and ultrasonics.

  16. Quasi experimental designs in pharmacist intervention research.

    PubMed

    Krass, Ines

    2016-06-01

    Background In the field of pharmacist intervention research it is often difficult to conform to the rigorous requirements of the "true experimental" models, especially the requirement of randomization. When randomization is not feasible, a practice based researcher can choose from a range of "quasi-experimental designs" i.e., non-randomised and at time non controlled. Objective The aim of this article was to provide an overview of quasi-experimental designs, discuss their strengths and weaknesses and to investigate their application in pharmacist intervention research over the previous decade. Results In the literature quasi experimental studies may be classified into five broad categories: quasi-experimental design without control groups; quasi-experimental design that use control groups with no pre-test; quasi-experimental design that use control groups and pre-tests; interrupted time series and stepped wedge designs. Quasi-experimental study design has consistently featured in the evolution of pharmacist intervention research. The most commonly applied of all quasi experimental designs in the practice based research literature are the one group pre-post-test design and the non-equivalent control group design i.e., (untreated control group with dependent pre-tests and post-tests) and have been used to test the impact of pharmacist interventions in general medications management as well as in specific disease states. Conclusion Quasi experimental studies have a role to play as proof of concept, in the pilot phases of interventions when testing different intervention components, especially in complex interventions. They serve to develop an understanding of possible intervention effects: while in isolation they yield weak evidence of clinical efficacy, taken collectively, they help build a body of evidence in support of the value of pharmacist interventions across different practice settings and countries. However, when a traditional RCT is not feasible for

  17. Assessing Students' Experimentation Processes in Guided Inquiry

    ERIC Educational Resources Information Center

    Emden, Markus; Sumfleth, Elke

    2016-01-01

    In recent science education, experimentation features ever more strongly as a method of inquiry in science classes rather than as a means to illustrate phenomena. Ideas and materials to teach inquiry abound. Yet, tools for assessing students' achievement in their processes of experimentation are lacking. The present study assumes a basal,…

  18. The 1985 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Thomas, L. R. (Editor); Mosier, F. L. (Editor)

    1986-01-01

    The 1985 Get Away Special (GAS) Experimenter's Symposium provided a formal opportunity for GAS experimenters to share the results of their projects. The focus is on payloads that have been flown on Shuttle missions, and on GAS payloads that will be flown in the near future.

  19. Experimental methodologies to support aircraft icing analysis

    NASA Technical Reports Server (NTRS)

    Hansman, R. John, Jr.; Kirby, Mark S.

    1987-01-01

    The experimental methodologies are illustrated by graphs, charts and line drawings. Typical ultrasonic echo signals for dry and wet ice growth, ice accretion rates for various tunnel configurations, the experimental configuration for flight tests of the ultrasonic measuring system and heat balance models used to predict ice growth are among the topics that are illustrated and briefly discussed.

  20. 14 CFR 21.191 - Experimental certificates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Experimental certificates. 21.191 Section 21.191 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS Airworthiness Certificates § 21.191 Experimental...