WorldWideScience

Sample records for mev enriched targets

  1. Measure of uranium enrichment by 14 MeV neutron irradiation

    International Nuclear Information System (INIS)

    Rezende, H.R.

    1987-01-01

    A non-destructive technique for the determination of uranium in UO 2 samples was developed, marking use of the change in the fission cross of a nuclide with the neutron energy. The active interrogation method was used by irradiating the samples with pulsed 14 MeV neutrons and furtherdetection of delayed fission neutrons. In order to descriminated U-238 from U-235 the neutron energy was tailored by means of two concentric cylinders of lead and paraffin/poliethylene, 11 and 4 cm thick. Between neutron pulses, delayed neutrons from fission were detected by a long counter built with five BF 3 proportional counters. Calibration curves for enrichment and total mass versus delayed neutron response were obtained using available UO 2 pellets of Known enrichment. Enrichment detection limit, obtained with 95% confidence level by the the Student distribution was estimated to be 0.33%. The minimal detectable mass was estimated to be 4.4 g. (Author) [pt

  2. Measurement of uranium enrichment by 14 MeV neutron irradiation

    International Nuclear Information System (INIS)

    Rezende, H.R.

    1987-01-01

    a non-destructive technique for the determination of uranium in UO 2 samples was developed, making use of the change in the fission cross section of a nuclide with the neutron energy. The active interrogation method was used by irradiating the samples with pulsed 14 MeV neutrons and further detection of delayed fission neutrons. In order to discriminate U-238 from U-235 the neutron energy was tailored by means of two concentric cylinders of lead and paraffin/poliethylene, 11 and 4 cm thick. Between neutron pulses, delayed neutrons from fission were detected by a long counter built with five BF 3 proportional counters. Calibration curves for enrichment and total mass versus delayed neutron response were obtained using available UO 2 pellets of known enrichment. Enrichment detection limit, obtained with 95% confidence level by the Student distribution was estimated to be 0.33%. The minimal detectable mass was estimated to be 4.4 g. (author) [pt

  3. Preparation of isotopically enriched mercury sulphide targets

    Energy Technology Data Exchange (ETDEWEB)

    Szerypo, J.; Friebel, H.U.; Frischke, D.; Grossman, R.; Maier, H.J. [Dept. fuer Physik, Univ. Muenchen (LMU) (Germany); Maier-Leibnitz-Lab. (MLL), Garching (Germany)

    2007-07-01

    The primary difficulty in performing nuclear reactions on mercury is to obtain a suitable target. The primary difficulty in performing nuclear reactions on mercury is to obtain a suitable target. The utilization of amalgam targets has been reported in early publications. These targets, however, were lacking homogeneity and in-beam stability. A thorough investigation of literature shows, that HgS, because of its comparatively high chemical and mechanical stability, is one of the more adequate Hg compounds for accelerator target applications. In this presentation we describe the production of HgS targets consisting of an enriched Hg isotope and S of natural isotopic abundance, starting up from HgO. Following the outline given in [3], in this special case HgS can be prepared by dissolving HgO in diluted HNO{sub 3} and subsequent precipitation of the black HgS modification with gaseous H{sub 2}S. Last step of the target production procedure is evaporation-condensation of HgS in vacuum. In the present case, HgS layers of 500 {mu}g/cm{sup 2} on a backing carbon foil of 26 {mu}g/cm{sup 2} with a protective carbon layer of about 20 {mu}g/cm{sup 2} thickness on top of the HgS layer were produced. (orig.)

  4. Neutron yield of thick {sup 12}C and {sup 13}C targets with 20 and 30 MeV deuterons

    Energy Technology Data Exchange (ETDEWEB)

    Lhersonneau, G.; Fadil, M. [GANIL, Caen (France); Malkiewicz, T. [CSC - IT Center for Science Ltd., Espoo (Finland); Gorelov, D.; Sorri, J.; Trzaska, W.H. [University of Jyvaskyla, Department of Physics, Jyvaskyla (Finland); Jones, P.; Ngcobo, P.Z. [iThemba Laboratory for Accelerator Based Science, Western Cape (South Africa)

    2016-12-15

    The neutron yield of thick targets of carbon, natural and enriched in {sup 13}C, bombarded by deuterons of 20 and 30 MeV has been measured by the activation method. The gain with respect to a {sup 12}C target is the same as with protons beams. The yield ratio is about 1.2 only and hardly can justify the use of a {sup 13}C target with deuteron beams. The data, apart from being of interest for the design of facilities where secondary neutron beams are used, provide a test case for calculations where both beam and target have a weakly bound neutron. The MCNPx code version 2.6.0, despite failing to reproduce some details of the experimental distributions, describes their global properties fairly well, especially the relative yields of the {sup 12}C and {sup 13}C targets. (orig.)

  5. Availability of enriched isotopic material for accelerator targets

    International Nuclear Information System (INIS)

    Newman, E.

    1982-01-01

    The electromagnetic isotope enrichment facility at ORNL provides a broad spectrum of highly enriched stable isotopes to the worldwide scientific community. The continued timely availability of these materials is of vital importance in many areas of basic research and, in particular, as source material for the fabrication of accelerator targets. A brief description of the facility and its capabilities and limitations is presented

  6. Cyclotron production of {sup 61}Cu using natural Zn and enriched {sup 64}Zn targets

    Energy Technology Data Exchange (ETDEWEB)

    Asad, A. H.; Smith, S. V.; Chan, S.; Jeffery, C. M.; Morandeau, L.; Price, R. I. [RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth, Australia, Imaging and Applied Physics, Curtin University, Perth, Australia, and Center of Excellence in Anti-matter Matter Studies, Australian National University, Can (Australia); Brookhaven National Laboratory, Upton, NY (United States) and Center of Excellence in Anti-matter Matter Studies, Australian National University, Canberra (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth (Australia); Center of Excellence in Anti-matter Matter Studies, Australian National University, Canberra, Australia, and Chemistry, University of Western Australia, Pe (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth (Australia); RAPID PET Labs, Medical Technology and Physics, Sir Charles Gairdner Hospital, Perth, Australia and Physics, University of Western Australia, Perth (Australia)

    2012-12-19

    Copper-61 ({sup 61}Cu) shares with {sup 64}Cu certain advantages for PET diagnostic imaging, but has a shorter half-life (3.4hr vs. 12.7hr) and a greater probability of positron production per disintegration (61% vs. 17.9%). One important application is for in vivo imaging of hypoxic tissue. In this study {sup 61}Cu was produced using the {sup 64}Zn(p,{alpha}){sup 61}Cu reaction on natural Zn or enriched {sup 64}Zn targets. The enriched {sup 64}Zn (99.82%) was electroplated onto high purity gold or silver foils or onto thin Al discs. A typical target bombardment used 30{mu}A; at 11.7, 14.5 or 17.6MeV over 30-60min. The {sup 61}Cu (radiochemical purity of >95%) was separated using a combination of cation and anion exchange columns. The {sup 64}Zn target material was recovered after each run, for re-use. In a direct comparison with enriched {sup 64}Zn-target results, {sup 61}Cu production using the cheaper {sup nat}Zn target proved to be an effective alternative.

  7. Low enrichment Mo-99 target development program at ANSTO

    International Nuclear Information System (INIS)

    Donlevy, Therese M.; Anderson, Peter J.; Beattie, David; Braddock, Ben; Fulton, Scott; Godfrey, Robert; Law, Russell; McNiven, Scott; Sirkka, Pertti; Storr, Greg; Wassink, David; Wong, Alan; Yeoh, Guan

    2002-01-01

    The Australian Nuclear Science and Technology Organisation (ANSTO, formerly AAEC) has been producing fission product Mo-99 in HIFAR, from the irradiation of Low Enrichment Uranium (LEU) UO 2 targets, for nearly thirty years. Over this period, the U-235 enrichment has been increased in stages, from natural to 1.8% to 2.2%. The decision to provide Australia with a replacement research reactor (RRR) for HIFAR has created an ideal opportunity to review and improve the current Mo-99 production process from target design through to chemical processing and waste management options. ANSTO has entered into a collaboration with Argonne National Laboratory (RERTR) to develop a target using uranium metal foil with U-235 enrichment of less than 20% The initial focus has been to demonstrate use of LEU foil targets in HIFAR, using existing irradiation methodology. The current effort focussed on designing a target assembly with optimised thermohydraulic characteristics to accommodate larger LEU foils to meet Mo-99 production needs. The ultimate goal is to produce an LEU target suitable for use in the Replacement Research Reactor when it is commissioned in 2005. This paper reports our activities on: - The regulatory approval processes required in order to undertake irradiation of this new target; -Supporting calculations (neutronics, computational fluid dynamics) for safety submission; - Design challenges and changes to prototype irradiation; - Trial irradiation of LEU foil target in HIFAR; - Future target and rig development program at ANSTO. (author)

  8. Measurement of neutron yield by 62 MeV proton beam on a thick beryllium target

    Energy Technology Data Exchange (ETDEWEB)

    Osipenko, M., E-mail: osipenko@ge.infn.it [INFN, sezione di Genova, 16146 Genova (Italy); Ripani, M. [INFN, sezione di Genova, 16146 Genova (Italy); Alba, R. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Ricco, G. [INFN, sezione di Genova, 16146 Genova (Italy); Schillaci, M. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Barbagallo, M. [INFN, sezione di Bari, 70126 Bari (Italy); Boccaccio, P. [INFN, Laboratori Nazionali di Legnaro, 35020 Legnaro (Italy); Celentano, A. [Dipartimento di Fisica dell' Università di Genova, 16146 Genova (Italy); Colonna, N. [INFN, sezione di Bari, 70126 Bari (Italy); Cosentino, L.; Del Zoppo, A.; Di Pietro, A. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Esposito, J. [INFN, Laboratori Nazionali di Legnaro, 35020 Legnaro (Italy); Figuera, P.; Finocchiaro, P. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Kostyukov, A. [Moscow State University, Moscow 119992 (Russian Federation); Maiolino, C.; Santonocito, D.; Scuderi, V. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Viberti, C.M. [Dipartimento di Fisica dell' Università di Genova, 16146 Genova (Italy)

    2013-09-21

    The design of a low-power prototype of neutron amplifier recently proposed within the INFN-E project indicated the need for more accurate data on the neutron yield produced by a proton beam with energy of about 70 MeV impinging on a thick beryllium target. Such measurement was performed at the LNS superconducting cyclotron, covering a wide angular range from 0° to 150° and a complete neutron energy interval from thermal to beam energy. Neutrons with energy above 0.5 MeV were measured by liquid scintillators exploiting their time of flight to determine the kinetic energy. For lower energy neutrons, down to thermal energy, a {sup 3}He detector was used. The obtained data are in good agreement with previous measurements at 0° using 66 MeV proton beam, covering neutron energies >10MeV, as well as with measurements at few selected angles using protons of 46, 55 and 113 MeV energy. The present results extend the neutron yield data in the 60–70 MeV beam energy range. A comparison of measured yields to MCNP, FLUKA and Geant4 Monte Carlo simulations was performed.

  9. Deuteron stripping on beryllium target in the 100-2300 MeV energy range

    International Nuclear Information System (INIS)

    Lecolley, J.F.; Varignon, C.; Durand, D.; Le Brun, C.; Lecolley, F.R.; Lefebvres, F.; Louvel, M.; Thun, J.; Borne, F.; Martinez, E.; Menard, S.; Pras, P.; Boudard, A.; Duchazeaubeneix, J.C.; Durand, J.M.; Frehaut, J.; Hanappe, F.; Ledoux, X.; Legrain, R.; Leray, S.; Milleret, G.; Patin, Y.; Stuttge, L.; Terrien, Y.

    1999-01-01

    Cross sections for stripping and dissociation of deuterons interacting with Be targets in the 100-2300 MeV energy range have been measured. Comparisons with model calculations suggest a dominant contribution of the stripping process. It is also shown that the deuteron break-up cross section exhibits the same energy dependence as the nucleon-nucleon cross section. (orig.)

  10. The 270 MeV deuteron beam polarimeter at the Nuclotron Internal Target Station

    Energy Technology Data Exchange (ETDEWEB)

    Kurilkin, P.K. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Moscow State Institute of Radio-engineering Electronics and Automation (Technical University), Moscow (Russian Federation); Ladygin, V.P., E-mail: vladygin@jinr.ru [Joint Institute for Nuclear Research, Dubna (Russian Federation); Moscow State Institute of Radio-engineering Electronics and Automation (Technical University), Moscow (Russian Federation); Uesaka, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Suda, K. [RIKEN Nishina Center, Saitama (Japan); Gurchin, Yu.V.; Isupov, A.Yu. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Itoh, K. [Department of Physics, Saitama University, Saitama (Japan); Janek, M. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Physics Department, University of Zilina, 010 26 Zilina (Slovakia); Karachuk, J.-T. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Advanced Research Institute for Electrical Engineering, Bucharest (Romania); Kawabata, T. [Center for Nuclear Study, University of Tokyo, Tokyo 113-0033 (Japan); Khrenov, A.N.; Kiselev, A.S.; Kizka, V.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Kliman, J. [Institute of Physics of Slovak Academy of Sciences, Bratislava (Slovakia); Krasnov, V.A.; Livanov, A.N. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Institute for Nuclear Research, Moscow (Russian Federation); Maeda, Y. [Kyushi University, Hakozaki (Japan); Malakhov, A.I. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Matousek, V.; Morhach, M. [Institute of Physics of Slovak Academy of Sciences, Bratislava (Slovakia)

    2011-06-21

    A deuteron beam polarimeter has been constructed at the Internal Target Station at the Nuclotron of JINR. The polarimeter is based on spin-asymmetry measurements in the d-p elastic scattering at large angles and the deuteron kinetic energy of 270 MeV. It allows to measure vector and tensor components of the deuteron beam polarization simultaneously.

  11. Target asymmetry measurement of deuteron photodisintegration at a photon energy of 550 MeV

    International Nuclear Information System (INIS)

    Althoff, K.H.; Anton, G.; Bock, B.; Bour, D.; Erbs, P.; Ferber, W.; Gelhausen, H.; Haertel, U.; Havenith, W.; Jahnen, T.; Kaufmann, H.P.; Kaul, O.; Luecking, B.; Menze, D.; Meyer, W.; Miczaika, T.; Rennings, K.; Riechert, H.; Roderburg, E.; Ruhm, W.; Schenuit, E.; Schilling, E.; Schwille, W.; Sternal, G.; Sundermann, D.; Thiel, W.; Thiesmeyer, D.; Wagener, K.

    1984-01-01

    The target asymmetry of the deuteron photodisintegration was measured at a photon energy of 550+-50 MeV and at proton center-off-mass angles between 25 and 155 degrees. D-butanol and ND 3 were used as target material yielding a maximum deuteron polarization of 41%. Proton and neutron were detected in coincidence. The data show a structure which cannot be described by the existing analyses. (orig.)

  12. Interaction of 80 MeV PI+ with different targets: Track detector studies

    Energy Technology Data Exchange (ETDEWEB)

    Tabassum, L; Chohan, A S [Government Coll., Lahore. (Pakistan) Deptt. of Physics Khan, H.A. (Pakistan Inst. of Nuclear Science and Technology, Islamabad (Pakistan). Nuclear Engineering Div.)

    1990-04-01

    CR-39 and mica track detectors have been used in the study of the interactions of 80 MeV PI+ with thin targets of Bi, Pb, Ho, Sb. The binary fission cross sections, the length and angular distributions of etched tracks have been obtained. The cross-section values obtained by using CR-39 are higher as compared to those obtained with mica. (author).

  13. Interaction of 80 MeV PI+ with different targets: Track detector studies

    International Nuclear Information System (INIS)

    Tabassum, L.; Chohan, A.S.

    1990-01-01

    CR-39 and mica track detectors have been used in the study of the interactions of 80 MeV PI+ with thin targets of Bi, Pb, Ho, Sb. The binary fission cross sections, the length and angular distributions of etched tracks have been obtained. The cross-section values obtained by using CR-39 are higher as compared to those obtained with mica. (author)

  14. Confirm calculation of 12 MeV non-destructive testing electron linear accelerator target

    International Nuclear Information System (INIS)

    Ma Shudong; Zhang Rutong; Guo Yanbin; Zhou Yuan; Li Xuexian; Chen Yan

    2012-01-01

    The confirm calculation of 12 MeV non-destructive testing (NDT) electron linear accelerator (LINAC) target was studied. Firstly, the most optimal target thickness and related photon dose yield, distributions of dose rate, and related photon conversion efficiencies were got by calculation with specific analysis of the physical mechanism of the interactions between the beam and target; Secondly, the photon dose rate distribution, converter efficiencies, and thickness of various kinds of targets, such as W, Au, Ta, etc. were verified by MCNP simulation and the most optimal target was got using the MCNP code; Lastly, the calculation results of theory and MCNP were compared to confirm the validity of target calculation. (authors)

  15. 800-MeV proton irradiation of thorium and depleted uranium targets

    Energy Technology Data Exchange (ETDEWEB)

    Russell, G.J.; Brun, T.O.; Pitcher, E.J. [Los Alamos National Laboratory, NM (United States)] [and others

    1995-10-01

    As part of the Los Alamos Fertile-to-Fissile-Conversion (FERFICON) program in the late 1980`s, thick targets of the fertile materials thorium and depleted uranium were bombarded by 800-MeV protons to produce the fissile materials {sup 233}U and {sup 239}Pu, respectively. The amount of {sup 233}U made was determined by measuring the {sup 233}Pa activity, and the yield of {sup 239}Pu was deduced by measuring the activity of {sup 239}Np. For the thorium target, 4 spallation products and 34 fission products were also measured. For the depleted uranium target, 3 spallation products and 16 fission products were also measured. The number of fissions in each target was deduced from fission product mass-yield curves. In actuality, axial distributions of the products were measured, and the distributions were then integrated over the target volume to obtain the total number of products for each reaction.

  16. Comprehensive Measurement of Neutron Yield Produced by 62 MeV Protons on Beryllium Target

    International Nuclear Information System (INIS)

    Osipenko, M.; Ripani, M.; Ricco, G.; Alba, R.; Schillaci, M.; Cosentino, L.; Del Zoppo, A.; Di Pietro, A.; Figuera, P.; Finocchiaro, P.; Maiolino, C.; Santonocito, D.; Scuderi, V.; Barbagallo, M.; Colonna, N.; Boccaccio, P.; Esposito, J.; Celentano, A.; Viberti, C.M.; Kostyukov, A.

    2013-06-01

    A low-power prototype of neutron amplifier, based on a 70 MeV, high current proton cyclotron being installed at LNL for the SPES RIB facility, was recently proposed within INFN-E project. This prototype uses a thick Beryllium converter to produce a fast neutron spectrum feeding a sub-critical reactor core. To complete the design of such facility the new measurement of neutron yield from a thick Beryllium target was performed at LNS. This measurement used liquid scintillator detectors to identify produced neutrons by Pulse Shape Discrimination and Time of Flight technique to measure neutron energy in the range 0.5-62 MeV. To extend the covered neutron energy range 3 He detector was used to measure neutrons below 0.5 MeV. The obtained yields were normalized to the charge deposited by the proton beam on the metallic Beryllium target. These techniques allowed to achieve a wide angular coverage from 0 to 150 degrees and to explore almost complete neutron energy interval. (authors)

  17. Accelerator production of 99mTc with proton beams and enriched 100Mo targets

    International Nuclear Information System (INIS)

    Lagunas-Solar, M.C.

    1999-01-01

    The direct production of 99m Tc has been developed based upon the use of the 100 Mo(p,2n) 99m Tc reaction (Q= -7.9 MeV), using enriched 100 Mo targets and accelerated protons of 99m Tc yields measured in this work reached 851 ± 77 MBq/μA/h (23.0 ± 3.0 mCi/μA/h) at end-of-bombardment (EOB) in the 22-12 MeV energy region, with 96 Tc (4.35 d) as the only detectable impurity at - accelerators, and by extracting multiple H + beams to bombard a single or an array of enriched 100 Mo targets, this method could provide nearly 851 GBq (23 Ci) of 99m Tc in 1-h bombardments. Because of this large-batch potential, this new method appears to be an effective alternative to the production and distribution of 99 Mo → 99m Tc generator systems, although it may be limited to daily, regional/local distribution and use. 99m Tc produced in this fashion has high radionuclidic and radiochemical purity, although its specific activity has not been determined. The accelerator-made 99m Tc has been shown to have similar physical and chemical characteristics than 99m Tc eluted from commercial fission-produced 99 Mo → 99m Tc generators. Technical and logistical factors need further study and analysis but the potential and the expected impact of this new method are clear in the context of the operation of large radionuclide distribution centers as well as for small programs in developing regions. (author)

  18. Progress on the IPNS Enriched Uranium Booster Target

    International Nuclear Information System (INIS)

    Knox, A.E.; Carpenter, J.M.; Bailey, J.L.

    1986-09-01

    We describe the Enriched Uranium Booster Target designed for use in Argonne's Intense Pulsed Neutron Source. This report contains a general description of the system, and descriptions of the thermal-hydraulic and loss-of-coolant accident analyses, of the neutronic, criticality and power density calculations, of the assessment of radiation and thermal cycling growth, and of the disk fabrication methods. We also describe the calculations of radionuclide buildup and the related hazards analysis and our calculations of the temperature and stress profiles in the disks, and briefly allude to considerations of security and safeguards

  19. Target irradiation facility and targetry development at 160 MeV proton beam of Moscow linac

    CERN Document Server

    Zhuikov, B L; Konyakhin, N A; Vincent, J

    1999-01-01

    A facility has been built and successfully operated with the 160 MeV proton beam of Moscow Meson factory LINAC, Institute for Nuclear Research (INR) of Russian Academy of Science, Troitsk. The facility was created for various isotope production goals as well as for fundamental nuclear investigations at high intensity beam (100 mu A and more). An important part of the facility targetry system is a high-intensity beam monitoring collimator device. Measurements of the temperature distribution between collimator sectors, cooling water flow and temperature, and the beam current, provide an opportunity to compute beam losses and beam position. The target holder design allows easy insertion by manipulator and simultaneous bombardment of several different targets of various types and forms, and variation of proton energy on each target over a wide range below 160 MeV. The main target utilized for commercial sup 8 sup 2 Sr isotope production is metallic rubidium in a stainless-steel container. A regular wet chemistry ...

  20. Interaction of 14 MeV neutrons with hydrogenated target proton emission calculation

    International Nuclear Information System (INIS)

    Martin, G.; Perez, N.; Desdin.

    1996-01-01

    Using neutron emission data of a 14 MeV neutron generator, a paraffin target, and based on the n + H 1 → n '+ p reaction, have been obtained the characteristics of the proton emission in a proton-neutron mixed field. It was used Monte Carlo simulation and it was obtained the proton output as function of the converter width and the energy spectrum of protons corresponding to different converter thickness. Among 0.07 and 0.2 cm there is a maximum zone for the proton emission. The energy spectrum agrees with obtained on previous papers. Figures showing these results are provided

  1. Measurement of neutron yield by 62 MeV proton beam on a thick Beryllium target

    International Nuclear Information System (INIS)

    Alba, R; Cosentino, G; Zoppo, A Del; Pietro, A Di; Figuera, P; Finocchiaro, P; Maiolino, C; Santonocito, D; Schillaci, M; Barbagallo, M; Colonna, N; Boccaccio, P; Esposito, J; Celentano, A; Osipenko, M; Ricco, G; Ripani, M; Viberti, C M; Kostyukov, A

    2013-01-01

    In the framework of research on IVth generation reactors and high intensity neutron sources a low-power prototype neutron amplifier was recently proposed by INFN. It is based on a low-energy, high current proton cyclotron, whose beam, impinging on a thick Beryllium converter, produces a fast neutron spectrum. The world database on the neutron yield from thick Beryllium target in the 70 MeV proton energy domain is rather scarce. The new measurement was performed at LNS, covering a wide angular range from 0 to 150 degrees and an almost complete neutron energy interval. In this contribution the preliminary data are discussed together with the proposed ADS facility.

  2. 44gSc production using a water target on a 13 MeV cyclotron

    International Nuclear Information System (INIS)

    Hoehr, Cornelia; Oehlke, Elisabeth; Benard, Francois; Lee, Chris Jaeil; Hou, Xinchi; Badesso, Brian; Ferguson, Simon; Miao, Qing; Yang, Hua; Buckley, Ken; Hanemaayer, Victoire; Zeisler, Stefan; Ruth, Thomas; Celler, Anna; Schaffer, Paul

    2014-01-01

    Introduction: Access to promising radiometals as isotopes for novel molecular imaging agents requires that they are routinely available and inexpensive to obtain. Proximity to a cyclotron center outfitted with solid target hardware, or to an isotope generator for the metal of interest is necessary, both of which can introduce significant hurdles in development of less common isotopes. Herein, we describe the production of 44 Sc (t 1/2 = 3.97 h, E avg,β + = 1.47 MeV, branching ratio = 94.27%) in a solution target and an automated loading system which allows a quick turn-around between different radiometallic isotopes and therefore greatly improves their availability for tracer development. Experimental yields are compared to theoretical calculations. Methods: Solutions containing a high concentration (1.44–1.55 g/mL) of natural-abundance calcium nitrate tetrahydrate (Ca(NO 3 ) 2 · 4 H 2 O) were irradiated on a 13 MeV proton-beam cyclotron using a standard liquid target. 44g Sc was produced via the 44 Ca(p,n) 44g Sc reaction. Results: 44g Sc was produced for the first time in a solution target with yields sufficient for early radiochemical studies. Saturation yields of up to 4.6 ± 0.3 MBq/μA were achieved using 7.6 ± 0.3 μA proton beams for 60.0 ± 0.2 minutes (number of runs n = 3). Experimental data and calculation results are in fair agreement. Scandium was isolated from the target mixture via solid-phase extraction with 88 ± 6% (n = 5) efficiency and successfully used for radiolabelling experiments. The demonstration of the production of 44 Sc in a liquid target greatly improves its availability for tracer development

  3. Differential production cross sections for charged particles produced by 590 MeV proton bombardment of thin metal targets

    International Nuclear Information System (INIS)

    Howe, S.D.; Cierjacks, S.; Hino, Y.; Raupp, F.; Rainbow, M.T.; Swinhoe, M.T.; Buth, L.

    1981-01-01

    Differential production cross sections have been measured for the reactions (p,p), (p,d), (p,t) and (p,π+-) using the 590 MeV proton beam at SIN. Here we report measurements made on thin targets of aluminium, niobium, lead, and uranium at laboratory angles of 90 0 and 157 0 . The data were taken over a proton energy range of about 50 MeV to 590 MeV. Differential cross sections are reported along with predictions by the intranuclear-cascade/evaporation model as computed by HETC. (orig.)

  4. Residual Nuclides Induced in Cu Target by a 250 MeV Proton Beam

    International Nuclear Information System (INIS)

    Zhang Hong-Bin; Zhang Xue-Ying; Ma Fei; Ju Yong-Qin; Ge Hong-Lin; Chen Liang; Zhang Yan-Bin; Li Yan-Yan; Luo Peng; Wang Jian-Guo; Wan Bo; Xu Xiao-Wei; Wei Ji-Fang; Zhou Bin

    2015-01-01

    Residual nuclide production is studied experimentally by bombarding a Cu target with a 250 MeV proton beam. The data are measured by the off-line γ-spectroscopy method. Six nuclides are identified and their cross sections are determined. The corresponding calculated results by the MCNPX and GEANT4 codes are compared with the experimental data to check the validity of the codes. A comparison shows that the MCNPX simulation has a better agreement with the experiment. The energy dependence of residual nuclide production is studied with the aid of MCNPX simulation, and it is found that the mass yields for the nuclides in the light mass region increase significantly with the proton energy. (paper)

  5. Theoretical modeling of yields for proton-induced reactions on natural and enriched molybdenum targets.

    Science.gov (United States)

    Celler, A; Hou, X; Bénard, F; Ruth, T

    2011-09-07

    Recent acute shortage of medical radioisotopes prompted investigations into alternative methods of production and the use of a cyclotron and ¹⁰⁰Mo(p,2n)(99m)Tc reaction has been considered. In this context, the production yields of (99m)Tc and various other radioactive and stable isotopes which will be created in the process have to be investigated, as these may affect the diagnostic outcome and radiation dosimetry in human studies. Reaction conditions (beam and target characteristics, and irradiation and cooling times) need to be optimized in order to maximize the amount of (99m)Tc and minimize impurities. Although ultimately careful experimental verification of these conditions must be performed, theoretical calculations can provide the initial guidance allowing for extensive investigations at little cost. We report the results of theoretically determined reaction yields for (99m)Tc and other radioactive isotopes created when natural and enriched molybdenum targets are irradiated by protons. The cross-section calculations were performed using a computer program EMPIRE for the proton energy range 6-30 MeV. A computer graphical user interface for automatic calculation of production yields taking into account various reaction channels leading to the same final product has been created. The proposed approach allows us to theoretically estimate the amount of (99m)Tc and its ratio relative to (99g)Tc and other radioisotopes which must be considered reaction contaminants, potentially contributing to additional patient dose in diagnostic studies.

  6. Solution-based targeted genomic enrichment for precious DNA samples

    Directory of Open Access Journals (Sweden)

    Shearer Aiden

    2012-05-01

    Full Text Available Abstract Background Solution-based targeted genomic enrichment (TGE protocols permit selective sequencing of genomic regions of interest on a massively parallel scale. These protocols could be improved by: 1 modifying or eliminating time consuming steps; 2 increasing yield to reduce input DNA and excessive PCR cycling; and 3 enhancing reproducible. Results We developed a solution-based TGE method for downstream Illumina sequencing in a non-automated workflow, adding standard Illumina barcode indexes during the post-hybridization amplification to allow for sample pooling prior to sequencing. The method utilizes Agilent SureSelect baits, primers and hybridization reagents for the capture, off-the-shelf reagents for the library preparation steps, and adaptor oligonucleotides for Illumina paired-end sequencing purchased directly from an oligonucleotide manufacturing company. Conclusions This solution-based TGE method for Illumina sequencing is optimized for small- or medium-sized laboratories and addresses the weaknesses of standard protocols by reducing the amount of input DNA required, increasing capture yield, optimizing efficiency, and improving reproducibility.

  7. Neutron spectrum at 900 from 800 MeV (p,n) reactions on a Ta target

    International Nuclear Information System (INIS)

    Howe, S.D.; Lisowski, P.W.; King, N.S.P.; Russell, G.J.; Donnert, H.J.

    1979-01-01

    The neutron time-of-flight spectrum produced by a thick tantalum target bombarded by 800-MeV protons was measured at an angle of 90 0 . The data were taken at the Weapons Neutron Research facility by use of a cylindrical Ta target with a radius of 1.27 cm and a length of 15 cm. An NE-213 liquid scintillator was used to detect the neutrons over an energy range of 0.5 to 350 MeV. The neutron yield is presented and compared to a intranuclear-cascade/evaporation model prediction. 3 figures

  8. Projectile and target fragmentation at intermediate energies (20 MeV <= E/A <= 100 MeV)

    International Nuclear Information System (INIS)

    Dayras, R.A.

    1985-04-01

    In order to follow the evolution of the reaction mechanisms in the transition region of the intermediate energy range, detailed studies of projectile-like fragments from a 44 MeV/u 40 Ar projectile bombarding 27 Al and sup(NAT)T: targets have been made. Experimental results are given. Discussion of the data is presented: transfer reactions, isotopic distributions, the fragmentation model, and abrasion model are used in the discussion

  9. Simulation study of neutron production in thick beryllium targets by 35 MeV and 50.5 MeV proton beams

    Science.gov (United States)

    Shin, Jae Won; Park, Tae-Sun

    2017-09-01

    A data-driven nuclear model dedicated to an accurate description of neutron productions in beryllium targets bombarded by proton beams is developed as a custom development that can be used as an add-on to GEANT4 code. The developed model, G4Data(Endf7.1), takes as inputs the total and differential cross section data of ENDF/B-VII.1 for not only the charge-exchange 9Be(p,n)9B reaction which produces discrete neutrons but also the nuclear reactions relevant for the production of continuum neutrons such as 9Be(p,pn)8Be and 9Be(p,n α) 5Li . In our benchmarking simulations for two experiments with 35 MeV and 50.5 MeV proton beams impinged on 1.16 and 1.05 cm thick beryllium targets, respectively, we find that the G4Data(Endf7.1) model can reproduce both the total amounts and the spectral shapes of the measured neutron yield data in a satisfactory manner, while all the considered hadronic models of GEANT4 cannot.

  10. Characteristics of functional enrichment and gene expression level of human putative transcriptional target genes.

    Science.gov (United States)

    Osato, Naoki

    2018-01-19

    Transcriptional target genes show functional enrichment of genes. However, how many and how significantly transcriptional target genes include functional enrichments are still unclear. To address these issues, I predicted human transcriptional target genes using open chromatin regions, ChIP-seq data and DNA binding sequences of transcription factors in databases, and examined functional enrichment and gene expression level of putative transcriptional target genes. Gene Ontology annotations showed four times larger numbers of functional enrichments in putative transcriptional target genes than gene expression information alone, independent of transcriptional target genes. To compare the number of functional enrichments of putative transcriptional target genes between cells or search conditions, I normalized the number of functional enrichment by calculating its ratios in the total number of transcriptional target genes. With this analysis, native putative transcriptional target genes showed the largest normalized number of functional enrichments, compared with target genes including 5-60% of randomly selected genes. The normalized number of functional enrichments was changed according to the criteria of enhancer-promoter interactions such as distance from transcriptional start sites and orientation of CTCF-binding sites. Forward-reverse orientation of CTCF-binding sites showed significantly higher normalized number of functional enrichments than the other orientations. Journal papers showed that the top five frequent functional enrichments were related to the cellular functions in the three cell types. The median expression level of transcriptional target genes changed according to the criteria of enhancer-promoter assignments (i.e. interactions) and was correlated with the changes of the normalized number of functional enrichments of transcriptional target genes. Human putative transcriptional target genes showed significant functional enrichments. Functional

  11. Hyb-Seq: combining target enrichment and genome skimming for plant phylogenomics

    Science.gov (United States)

    Kevin Weitemier; Shannon C.K. Straub; Richard C. Cronn; Mark Fishbein; Roswitha Schmickl; Angela McDonnell; Aaron. Liston

    2014-01-01

    • Premise of the study: Hyb-Seq, the combination of target enrichment and genome skimming, allows simultaneous data collection for low-copy nuclear genes and high-copy genomic targets for plant systematics and evolution studies. • Methods and Results: Genome and transcriptome assemblies for milkweed ( Asclepias syriaca ) were used to design enrichment probes for 3385...

  12. Hydrogen isotope double differential production cross sections induced by 62.7 MeV neutrons on a lead target

    International Nuclear Information System (INIS)

    Kerveno, M.; Haddad, F.; Eudes, Ph.; Kirchner, T.; Lebrun, C.; Slypen, I.; Meulders, J.P.; Le Brun, C.; Lecolley, F.R.; Lecolley, J.F.; Louvel, M.; Lefebvres, F.; Hilaire, S.; Koning, A.J.

    2002-01-01

    Double differential hydrogen isotope production cross sections have been extracted in 62.7 MeV neutron induced reactions on a lead target. The angular distribution was measured at eight angles from 20 deg. to 160 deg. allowing the extraction of angle-differential, energy differential, and total production cross sections. A first set of comparisons with several theoretical calculations is also presented

  13. Dynamic Pressure of Liquid Mercury Target During 800-MeV Proton Thermal Shock Tests

    International Nuclear Information System (INIS)

    Allison, S.W.; Andriulli, J.B.; Cates, M.R.; Earl, D.D.; Haines, J.R.; Morrissey, F.X.; Tsai, C.C.; Wender, S.

    2000-01-01

    Described here are efforts to diagnose transient pressures generated by a short-pulse (about 0.5 microseconds) high intensity proton (∼ 2 * 10 14 per pulse) beam. Proton energy is 800-MeV. The tests were performed at the Los Alamos Neutron Science Center - Weapons Neutron Research (LANSCE-WNR). Such capability is required for understanding target interaction for the Spallation Neutron Source project as described previously at this conference.1-4 The main approach to effect the pressure measurements utilized the deflection of a diaphragm in intimate contact with the mercury. There are a wide variety of diaphragm-deflection methods used in scientific and industrial applications. Many deflection-sensing approaches are typically used, including, for instance, capacitive and optical fiber techniques. It was found, however, that conventional pressure measurement using commercial pressure gages with electrical leads was not possible due to the intense nuclear radiation environment. Earlier work with a fiber optic strain gauge demonstrated the viability of using fiber optics for this environment

  14. Theoretical modeling of yields for proton-induced reactions on natural and enriched molybdenum targets

    Energy Technology Data Exchange (ETDEWEB)

    Celler, A; Hou, X [University of British Columbia, Vancouver, BC, Canada, (Canada); Benard, F; Ruth, T, E-mail: aceller@physics.ubc.ca, E-mail: xinchi@phas.ubc.ca, E-mail: fbenard@bccrc.ca, E-mail: truth@triumf.ca [BC Cancer Agency, Vancouver, BC (Canada)

    2011-09-07

    Recent acute shortage of medical radioisotopes prompted investigations into alternative methods of production and the use of a cyclotron and {sup 100}Mo(p,2n){sup 99m}Tc reaction has been considered. In this context, the production yields of {sup 99m}Tc and various other radioactive and stable isotopes which will be created in the process have to be investigated, as these may affect the diagnostic outcome and radiation dosimetry in human studies. Reaction conditions (beam and target characteristics, and irradiation and cooling times) need to be optimized in order to maximize the amount of {sup 99m}Tc and minimize impurities. Although ultimately careful experimental verification of these conditions must be performed, theoretical calculations can provide the initial guidance allowing for extensive investigations at little cost. We report the results of theoretically determined reaction yields for {sup 99m}Tc and other radioactive isotopes created when natural and enriched molybdenum targets are irradiated by protons. The cross-section calculations were performed using a computer program EMPIRE for the proton energy range 6-30 MeV. A computer graphical user interface for automatic calculation of production yields taking into account various reaction channels leading to the same final product has been created. The proposed approach allows us to theoretically estimate the amount of {sup 99m}Tc and its ratio relative to {sup 99g}Tc and other radioisotopes which must be considered reaction contaminants, potentially contributing to additional patient dose in diagnostic studies.

  15. Mung bean nuclease treatment increases capture specificity of microdroplet-PCR based targeted DNA enrichment.

    Directory of Open Access Journals (Sweden)

    Zhenming Yu

    Full Text Available Targeted DNA enrichment coupled with next generation sequencing has been increasingly used for interrogation of select sub-genomic regions at high depth of coverage in a cost effective manner. Specificity measured by on-target efficiency is a key performance metric for target enrichment. Non-specific capture leads to off-target reads, resulting in waste of sequencing throughput on irrelevant regions. Microdroplet-PCR allows simultaneous amplification of up to thousands of regions in the genome and is among the most commonly used strategies for target enrichment. Here we show that carryover of single-stranded template genomic DNA from microdroplet-PCR constitutes a major contributing factor for off-target reads in the resultant libraries. Moreover, treatment of microdroplet-PCR enrichment products with a nuclease specific to single-stranded DNA alleviates off-target load and improves enrichment specificity. We propose that nuclease treatment of enrichment products should be incorporated in the workflow of targeted sequencing using microdroplet-PCR for target capture. These findings may have a broad impact on other PCR based applications for which removal of template DNA is beneficial.

  16. Fast neutron distributions from Be and C thick targets bombarded with 80 and 160 MeV deuterons

    International Nuclear Information System (INIS)

    Pauwels, N.; Laurent, H.; Clapier, F.; Brandenburg, S.; Beijers, J. P .M.; Zegers, R. G. T.; Lebreton, H.; Saint-Laurent, M.G.; Mirea, M.

    2001-01-01

    Production of fast neutron studies have come to the fore in the past few years because of the great interest for the possible applications of induced fission to produce neutron rich ion beams. In this context, the main objective of the SPIRAL II (Systeme de Production d'Ions Radioactifs Acceleres en Ligne) and PARRNe (Production d'Atomes Radioactifs Riches en Neutrons) R and D projects is the investigation of the feasibility and of the optimum parameters for a neutron rich isotope source. Special attention is dedicated to the energy and angular distributions of the neutrons obtained through deuteron break--up in different types of converters and different incident energies. Analysis and modelling of such behaviors, together with the study of the yields of neutron induced fission, can be used to optimize the productivity of the fissioning target its geometry and designing it accordingly. The present report continues our previous studies realised for 17, 20, 28 and 200 MeV deuteron energies and it is focused on deuteron incident energies of 80 and 160 MeV. In the experiment, the double differential cross section for neutron production induced by 80 and 160 MeV deuterons impinging on thick C and Be targets, in which the incident deuterons were complete stopped, have been measured. The energy of the neutrons was determined from the time--of--flight (TOF) measurement. To obtain an energy resolution of about 4% for the fastest, forward--emitted neutrons, which have approximately beam velocity, the length of the flightpath for the detectors at angles up to 30 angle was chosen to be 6 m. At backward angles, where the neutron energies are lower, a shorter flightpath was chosen. A schematic drawing of the setup is shown. A 100 mm thick Be target and a 70 mm thick C target were used. Results are exemplified with the angular and energy distributions of neutron obtained for Be target at 80 MeV. (authors)

  17. High intensity proton beam transportation through fringe field of 70 MeV compact cyclotron to beam line targets

    Science.gov (United States)

    Zhang, Xu; Li, Ming; Wei, Sumin; Xing, Jiansheng; Hu, Yueming; Johnson, Richard R.; Piazza, Leandro; Ryjkov, Vladimir

    2016-06-01

    From the stripping points, the high intensity proton beam of a compact cyclotron travels through the fringe field area of the machine to the combination magnet. Starting from there the beams with various energy is transferred to the switching magnet for distribution to the beam line targets. In the design of the extraction and transport system for the compact proton cyclotron facilities, such as the 70 MeV in France and the 100 MeV in China, the space charge effect as the beam crosses the fringe field has not been previously considered; neither has the impact on transverse beam envelope coupled from the longitudinal direction. Those have been concerned much more with the higher beam-power because of the beam loss problem. In this paper, based on the mapping data of 70 MeV cyclotron including the fringe field by BEST Cyclotron Inc (BEST) and combination magnet field by China Institute of Atomic Energy (CIAE), the beam extraction and transport are investigated for the 70 MeV cyclotron used on the SPES project at Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro (INFN-LNL). The study includes the space charge effect and longitudinal and transverse coupling mentioned above, as well as the matching of beam optics using the beam line for medical isotope production as an example. In addition, the designs of the ±45° switching magnets and the 60° bending magnet for the extracted beam with the energy from 35 MeV to 70 MeV have been made. Parts of the construction and field measurements of those magnets have been done as well. The current result shows that, the design considers the complexity of the compact cyclotron extraction area and fits the requirements of the extraction and transport for high intensity proton beam, especially at mA intensity levels.

  18. High intensity proton beam transportation through fringe field of 70 MeV compact cyclotron to beam line targets

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xu, E-mail: emmazhang103@gmail.com [China Institute of Atomic Energy (China); Li, Ming; Wei, Sumin; Xing, Jiansheng; Hu, Yueming [China Institute of Atomic Energy (China); Johnson, Richard R.; Piazza, Leandro; Ryjkov, Vladimir [BEST Cyclotron Inc (Canada)

    2016-06-01

    From the stripping points, the high intensity proton beam of a compact cyclotron travels through the fringe field area of the machine to the combination magnet. Starting from there the beams with various energy is transferred to the switching magnet for distribution to the beam line targets. In the design of the extraction and transport system for the compact proton cyclotron facilities, such as the 70 MeV in France and the 100 MeV in China, the space charge effect as the beam crosses the fringe field has not been previously considered; neither has the impact on transverse beam envelope coupled from the longitudinal direction. Those have been concerned much more with the higher beam-power because of the beam loss problem. In this paper, based on the mapping data of 70 MeV cyclotron including the fringe field by BEST Cyclotron Inc (BEST) and combination magnet field by China Institute of Atomic Energy (CIAE), the beam extraction and transport are investigated for the 70 MeV cyclotron used on the SPES project at Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro (INFN–LNL). The study includes the space charge effect and longitudinal and transverse coupling mentioned above, as well as the matching of beam optics using the beam line for medical isotope production as an example. In addition, the designs of the ±45° switching magnets and the 60° bending magnet for the extracted beam with the energy from 35 MeV to 70 MeV have been made. Parts of the construction and field measurements of those magnets have been done as well. The current result shows that, the design considers the complexity of the compact cyclotron extraction area and fits the requirements of the extraction and transport for high intensity proton beam, especially at mA intensity levels.

  19. Production of residual nuclides by proton-induced reactions on target W at the energy of 72 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Miah, Moazzem Hossain [Univ. of Chittagong, Dept. of Physics, Chittagong (Bangladesh); Kuhnhenn, Jochen; Herpers, Ulrich [Univ. of Cologne, Dept. of Nuclear Chemistry, Cologne (Germany); Michel, Rolf [University of Hannover, Centre for Radiation Protection and Radioecology (Germany); Kubik, Peter [Paul Scherrer Inst., c/o Institute for Particle Physics, ETH Hoenggerberg, Zuerich (Switzerland)

    2002-08-01

    Investigations of cross-sections for residual nuclide production on the target element W by proton-induced reactions were performed by irradiating the target with 72 MeV protons using the cyclotron facilities at Paul-Scherrer Institute, Zurich, Switzerland. Residual nuclides were measured by gamma-spectrometry of HpGe detectors calibrated with standard gamma sources. The measured data contains 104 individual cross-sections for 20 identified nuclides in the proton energies between 52.5 - 68.9 MeV. These nuclear data is important in the study of spallation neutron source and in accelerator driven technologies such as waste transmutation and energy amplification. The present data are compared with the shape of the excitation functions of earlier only one measurement at higher energies and they are in good agreement to each other. (author)

  20. The efficacy of high-throughput sequencing and target enrichment on charred archaeobotanical remains

    DEFF Research Database (Denmark)

    Nistelberger, H. M.; Smith, O.; Wales, Nathan

    2016-01-01

    . It has been suggested that high-throughput sequencing (HTS) technologies coupled with DNA enrichment techniques may overcome some of these limitations. Here we report the findings of HTS and target enrichment on four important archaeological crops (barley, grape, maize and rice) performed in three...... lightly-charred maize cob. Even with target enrichment, this sample failed to yield adequate data required to address fundamental questions in archaeology and biology. We further reanalysed part of an existing dataset on charred plant material, and found all purported endogenous DNA sequences were likely...

  1. Enrichment of target sequences for next-generation sequencing applications in research and diagnostics.

    Science.gov (United States)

    Altmüller, Janine; Budde, Birgit S; Nürnberg, Peter

    2014-02-01

    Abstract Targeted re-sequencing such as gene panel sequencing (GPS) has become very popular in medical genetics, both for research projects and in diagnostic settings. The technical principles of the different enrichment methods have been reviewed several times before; however, new enrichment products are constantly entering the market, and researchers are often puzzled about the requirement to take decisions about long-term commitments, both for the enrichment product and the sequencing technology. This review summarizes important considerations for the experimental design and provides helpful recommendations in choosing the best sequencing strategy for various research projects and diagnostic applications.

  2. Spallation Neutron Emission Spectra in Some Amphoter Target Nuclei by Proton Beam Up to 140 MeV Energy

    International Nuclear Information System (INIS)

    Yildirim, G.

    2008-01-01

    In the present study, the (p,xn) reaction neutron-emission spectra for some amphoter target nuclei as 27 A l, 64 Z n, 120 S n, and 208 P b were investigated up to 140 MeV incident proton energy. The pre-equilibrium calculations were calculated by using the hybrid model, the geometry dependent hybrid model, the full exciton model and the cascade exciton model. The reaction equilibrium component was calculated with a traditional compound nucleus model developed by Weisskopf Ewing. Calculation results have been discussed and compared with the available experimental data in literature

  3. Measured and calculated neutron yields for 100 MeV protons on thick targets of Pb and Li

    International Nuclear Information System (INIS)

    Jones, R.T.; Lone, M.A.; Okazaki, A.

    1983-01-01

    The neutron yield per proton from thick targets of lead and lithium irradiated with 100 MeV protons has been measured and calculated. The water bath method was used to measure the neutron production, and a Faraday cup for the beam current determination. Measured yields are 0.343 +- 0.021 for lead and 0.123 +- 0.007 for lithium. Corresponding yields calculated with the nucleon-meson transport code NMTC are 0.363 +- 0.002 and 0.160 +- 0.001. Measured and calculated thermal neutron distributions in the water bath are also compared

  4. Interaction of a 29 MeV 3He particle beam with a Cl4C vapour target

    International Nuclear Information System (INIS)

    Lleo Morilla, A.

    1963-01-01

    The interactions of a 29 MeV 3 H e particles beam on a Cl 4 C vapour target have been studied using the photographic method. differential cross-sections for the Cl( 3 He, 3 He)Cl elastic scattering and 1 2C( 3 He, α) 1 1C pick-up reaction are shown; the corresponding angular distributions in the centre-of-mass system have been compared with the predictions of optical model and A.B.M. theories. (Author) 21 refs

  5. Enrichment of putative PAX8 target genes at serous epithelial ovarian cancer susceptibility loci

    DEFF Research Database (Denmark)

    Kar, Siddhartha P; Adler, Emily; Tyrer, Jonathan

    2017-01-01

    BACKGROUND: Genome-wide association studies (GWAS) have identified 18 loci associated with serous ovarian cancer (SOC) susceptibility but the biological mechanisms driving these findings remain poorly characterised. Germline cancer risk loci may be enriched for target genes of transcription factors...... (TFs) critical to somatic tumorigenesis. METHODS: All 615 TF-target sets from the Molecular Signatures Database were evaluated using gene set enrichment analysis (GSEA) and three GWAS for SOC risk: discovery (2196 cases/4396 controls), replication (7035 cases/21 693 controls; independent from discovery...... to interact with PAX8 in the literature to the PAX8-target set and applying an alternative to GSEA, interval enrichment, further confirmed this association (P=0.006). Fifteen of the 157 genes from this expanded PAX8 pathway were near eight loci associated with SOC risk at P

  6. Low-enriched uranium high-density target project. Compendium report

    Energy Technology Data Exchange (ETDEWEB)

    Vandegrift, George; Brown, M. Alex; Jerden, James L.; Gelis, Artem V.; Stepinski, Dominique C.; Wiedmeyer, Stanley; Youker, Amanda; Hebden, Andrew; Solbrekken, G; Allen, C; Robertson., D; El-Gizawy, Sherif; Govindarajan, Srisharan; Hoyer, Annemarie; Makarewicz, Philip; Harris, Jacob; Graybill, Brian; Gunn, Andy; Berlin, James; Bryan, Chris; Sherman, Steven; Hobbs, Randy; Griffin, F. P.; Chandler, David; Hurt, C. J.; Williams, Paul; Creasy, John; Tjader, Barak; McFall, Danielle; Longmire, Hollie

    2016-09-01

    At present, most 99Mo is produced in research, test, or isotope production reactors by irradiation of highly enriched uranium targets. To achieve the denser form of uranium needed for switching from high to low enriched uranium (LEU), targets in the form of a metal foil (~125-150 µm thick) are being developed. The LEU High Density Target Project successfully demonstrated several iterations of an LEU-fission-based Mo-99 technology that has the potential to provide the world’s supply of Mo-99, should major producers choose to utilize the technology. Over 50 annular high density targets have been successfully tested, and the assembly and disassembly of targets have been improved and optimized. Two target front-end processes (acidic and electrochemical) have been scaled up and demonstrated to allow for the high-density target technology to mate up to the existing producer technology for target processing. In the event that a new target processing line is started, the chemical processing of the targets is greatly simplified. Extensive modeling and safety analysis has been conducted, and the target has been qualified to be inserted into the High Flux Isotope Reactor, which is considered above and beyond the requirements for the typical use of this target due to high fluence and irradiation duration.

  7. A Targeted Enrichment Strategy for Massively Parallel Sequencing of Angiosperm Plastid Genomes

    Directory of Open Access Journals (Sweden)

    Gregory W. Stull

    2013-02-01

    Full Text Available Premise of the study: We explored a targeted enrichment strategy to facilitate rapid and low-cost next-generation sequencing (NGS of numerous complete plastid genomes from across the phylogenetic breadth of angiosperms. Methods and Results: A custom RNA probe set including the complete sequences of 22 previously sequenced eudicot plastomes was designed to facilitate hybridization-based targeted enrichment of eudicot plastid genomes. Using this probe set and an Agilent SureSelect targeted enrichment kit, we conducted an enrichment experiment including 24 angiosperms (22 eudicots, two monocots, which were subsequently sequenced on a single lane of the Illumina GAIIx with single-end, 100-bp reads. This approach yielded nearly complete to complete plastid genomes with exceptionally high coverage (mean coverage: 717×, even for the two monocots. Conclusions: Our enrichment experiment was highly successful even though many aspects of the capture process employed were suboptimal. Hence, significant improvements to this methodology are feasible. With this general approach and probe set, it should be possible to sequence more than 300 essentially complete plastid genomes in a single Illumina GAIIx lane (achieving 50× mean coverage. However, given the complications of pooling numerous samples for multiplex sequencing and the limited number of barcodes (e.g., 96 available in commercial kits, we recommend 96 samples as a current practical maximum for multiplex plastome sequencing. This high-throughput approach should facilitate large-scale plastid genome sequencing at any level of phylogenetic diversity in angiosperms.

  8. Multiplex target enrichment using DNA indexing for ultra-high throughput SNP detection.

    LENUS (Irish Health Repository)

    Kenny, Elaine M

    2011-02-01

    Screening large numbers of target regions in multiple DNA samples for sequence variation is an important application of next-generation sequencing but an efficient method to enrich the samples in parallel has yet to be reported. We describe an advanced method that combines DNA samples using indexes or barcodes prior to target enrichment to facilitate this type of experiment. Sequencing libraries for multiple individual DNA samples, each incorporating a unique 6-bp index, are combined in equal quantities, enriched using a single in-solution target enrichment assay and sequenced in a single reaction. Sequence reads are parsed based on the index, allowing sequence analysis of individual samples. We show that the use of indexed samples does not impact on the efficiency of the enrichment reaction. For three- and nine-indexed HapMap DNA samples, the method was found to be highly accurate for SNP identification. Even with sequence coverage as low as 8x, 99% of sequence SNP calls were concordant with known genotypes. Within a single experiment, this method can sequence the exonic regions of hundreds of genes in tens of samples for sequence and structural variation using as little as 1 μg of input DNA per sample.

  9. The thick-target 9Be(d,n) neutron spectra for deuteron energies between 2.6 and 7.0-MeV

    International Nuclear Information System (INIS)

    Meadows, J.W.

    1991-11-01

    The measurement of the zero deg. neutron spectra and yields from deuterons incident on thick beryllium metal targets is described. 235 U and 238 U fission ion chambers were used as neutron detectors to span the neutron energy range above 0.05-MeV with a time resolution of ≤ 3 nanosec. Measurements were made for incident deuteron energies from 2.6 to 7.0-MeV, at 0.4-MeV intervals, using time-of-flight techniques with flight paths of 2.7 and 6.8 meters. The results are presented in graphical form and in tables

  10. Continuing investigations for technology assessment of 99Mo production from LEU [low enriched uranium] targets

    International Nuclear Information System (INIS)

    Vandegrift, G.F.; Kwok, J.D.; Marshall, S.L.; Vissers, D.R.; Matos, J.E.

    1987-01-01

    Currently much of the world's supply of 99m Tc for medical purposes is produced from 99 Mo derived from the fissioning of high enriched uranium (HEU). This paper presents the results of our continuing studies on the effects of substituting low enriched uranium (LEU) for HEU in targets for the production of fission product 99 Mo. Improvements in the electrodeposition of thin films of uranium metal continue to increase the appeal for the substitution of LEU metal for HEU oxide films in cylindrical targets. The process is effective for targets fabricated from stainless steel or zircaloy. Included is a cost estimate for setting up the necessary equipment to electrodeposit uranium metal on cylindrical targets. Further investigations on the effect of LEU substitution on processing of these targets are also reported. Substitution of uranium silicides for the uranium-aluminium alloy or uranium aluminide dispersed fuel used in current target designs will allow the substitution of LEU for HEU in these targets with equivalent 99 Mo-yield per target and no change in target geometries. However, this substitution will require modifications in current processing steps due to 1) the insolubility of uranium silicides in alkaline solutions and 2) the presence of significant quantities of silicate in solution. Results to date suggest that substitution of LEU for HEU can be achieved. (Author)

  11. Thick target spallation product yields from 800 MeV protons on tungsten

    International Nuclear Information System (INIS)

    Ullmann, J.L.; Staples, P.; Butler, G.

    1994-01-01

    A number of newly-conceived accelerator based technologies will employ medium-energy particles stopping in thick targets to produce large numbers of neutrons. It is important to quantify the residual radionuclides in the target because one must understand what nuclei and decay gammas are produced in order to design adequate shielding, to estimate ultimate waste disposal problems, and to predict possible effects of accidental dispersion during operation. Because stopping-length targets are considered, radionuclide production must be known as a function of energy. Moreover, secondary particle production, mostly neutrons, implies a need to be able to calculate particle transport. To test the overall ability to calculate radionuclide yields, a thick-target measurement was carried out and the results compared to detailed calculations. Although numerous measurements of thin-target spallation yields have been made, there have been only a few measurements on thick systems. The most complete study showed results for Pb and U systems. In this contribution, the authors report on measurements made for a stopping-length W target. Special efforts were made to measure short-lived isotopes, and reliable data on isotopes with two or three minute half-lives were obtained

  12. Combining target enrichment with barcode multiplexing for high throughput SNP discovery

    Directory of Open Access Journals (Sweden)

    Lunke Sebastian

    2010-11-01

    Full Text Available Abstract Background The primary goal of genetic linkage analysis is to identify genes affecting a phenotypic trait. After localisation of the linkage region, efficient genetic dissection of the disease linked loci requires that functional variants are identified across the loci. These functional variations are difficult to detect due to extent of genetic diversity and, to date, incomplete cataloguing of the large number of variants present both within and between populations. Massively parallel sequencing platforms offer unprecedented capacity for variant discovery, however the number of samples analysed are still limited by cost per sample. Some progress has been made in reducing the cost of resequencing using either multiplexing methodologies or through the utilisation of targeted enrichment technologies which provide the ability to resequence genomic areas of interest rather that full genome sequencing. Results We developed a method that combines current multiplexing methodologies with a solution-based target enrichment method to further reduce the cost of resequencing where region-specific sequencing is required. Our multiplex/enrichment strategy produced high quality data with nominal reduction of sequencing depth. We undertook a genotyping study and were successful in the discovery of novel SNP alleles in all samples at uniplex, duplex and pentaplex levels. Conclusion Our work describes the successful combination of a targeted enrichment method and index barcode multiplexing to reduce costs, time and labour associated with processing large sample sets. Furthermore, we have shown that the sequencing depth obtained is adequate for credible SNP genotyping analysis at uniplex, duplex and pentaplex levels.

  13. Preliminary investigations for technology assessment of 99Mo production from LEU [low enriched uranium] targets

    International Nuclear Information System (INIS)

    Vandegrift, G.F.; Chaiko, D.J.; Heinrich, R.R.; Kucera, E.T.; Jensen, K.J.; Poa, D.S.; Varma, R.; Vissers, D.R.

    1986-11-01

    This paper presents the results of preliminary studies on the effects of substituting low enriched uranium (LEU) for highly enriched uranium (HEU) in targets for the production of fission product 99 Mo. Issues that were addressed are: (1) purity and yield of the 99 Mo//sup 99m/Tc product, (2) fabrication of LEU targets and related concerns, and (3) radioactive waste. Laboratory experimentation was part of the efforts for issues (1) and (2); thus far, radioactive waste disposal has only been addressed in a paper study. Although the reported results are still preliminary, there is reason to be optimistic about the feasibility of utilizing LEU targets for 99 Mo production. 37 refs., 1 fig., 5 tabs

  14. Development of dissolution process for metal foil target containing low enriched uranium

    International Nuclear Information System (INIS)

    Srinivasan, B.; Hutter, J.C.; Johnson, G.K.; Vandegrift, G.F.

    1994-01-01

    About six times more low enriched uranium (LEU) metal is needed to produce the same quantity of 99 Mo as from a high enriched uranium (HEU) oxide target, under similar conditions of neutron irradiation. In view of this, the post-irradiation processing procedures of the LEU target are likely to be different from the Cintichem process procedures now in use for the HEU target. The authors have begun a systematic study to develop modified procedures for LEU target dissolution and 99 Mo separation. The dissolution studies include determination of the dissolution rate, chemical state of uranium in the solution, and the heat evolved in the dissolution reaction. From these results the authors conclude that a mixture of nitric and sulfuric acid is a suitable dissolver solution, albeit at higher concentration of nitric acid than in use for the HEU targets. Also, the dissolver vessel now in use for HEU targets is inadequate for the LEU target, since higher temperature and higher pressure will be encountered in the dissolution of LEU targets. The desire is to keep the modifications to the Cintichem process to a minimum, so that the switch from HEU to LEU can be achieved easily

  15. Acceleration of protons to above 6 MeV using H2O 'snow' nanowire targets

    International Nuclear Information System (INIS)

    Pomerantz, I.; Schleifer, E.; Nahum, E.; Eisenmann, S.; Botton, M.; Gordon, D.; Sprangel, P.; Zigler, A.

    2012-01-01

    A scheme is presented for using H 2 O 'snow' nanowire targets for the generation of fast protons. This novel method may relax the requirements for very high laser intensities, thus reducing the size and cost of laser based ion acceleration system.

  16. Filling and Recycling Apparatus of a Cyclotron Target with Enriched Krypton for Production of Radiopharmaceuticals

    Directory of Open Access Journals (Sweden)

    M. Vognar

    2001-01-01

    Full Text Available An apparatus for multiple filling of a cyclotron target with enriched Kr gas is described. The system is based on recycling pressurized gas by cryogenic pumping between the target tube and storage containers. The design and construction makes use of previous experience in the construction and operation of two analogue apparatuses for Xe124 high pressure gas targets, but major modifications have been incorporated, evoked by the different physical properties of Kr, by the character of the nuclear reaction, and by the demand for automation from the side of the end user.

  17. Thick-target neutron, gamma-ray, and radionuclide production for protons below 12 MeV on nickel and carbon beam-stops

    International Nuclear Information System (INIS)

    Chadwick, M.B.; Young, P.G.; Wilson, W.B.

    1998-03-01

    Nuclear model calculations using the GNASH code are described for protons below 12 MeV incident on nickel and carbon isotopes, for beam stop design in the Los Alamos Accelerator Production of Tritium Low Energy Demonstration Accelerator (LEDA) project. The GNASH calculations apply Hauser-Feshbach and preequilibrium reaction theories and can make use of pre-calculated direct reaction cross sections to low-lying residual nucleus states. From calculated thin target cross sections, thick target 6.7 MeV and 12 MeV proton-induced production of neutrons, gamma rays, and radionuclides are determined. Emission spectra of the secondary neutrons and gamma rays are also determined. The model calculations are validated through comparisons with experimental thin- and thick-target measurements. The results of this work are being utilized as source terms in MCNP analyses for LEDA

  18. A water-cooled target of a 14 MeV neutron source

    International Nuclear Information System (INIS)

    Ogawa, Masuro; Seki, Masahiro; Kawamura, Hiroshi; Sanokawa, Konomo

    1979-09-01

    For the cooling system of a stationary target for the fusion neutronics source (FNS), designed to meet the structural, thermal and hydraulic requirements, thermohydraulic experiments were made. In the heat transfer experiment, in place of an accelerator, electric-heater assemblies were used. The relation of head loss and heat transfer was obtained as a function of Reynolds number. The head loss was not large for flow rates up to 1.3 l/s. Neither vibration of the apparatus nor cavitation of water was observed even at the maximum flow rate. The heat load of 1 kW for the beam diameter of 15mm, i.e. the requirement of FNS, could be removed by 0.2 l/s water flow, with the target-surface maximum temperature kept below 200 0 C. Extrapolation of the experimental results showed that with the target system, the maximum heat load is 2.3 kW for the beam of diameter 15 mm. The value is sufficiently large compared with the heat load of FNS; with finned cooling surfaces, the heat loads up to 3.7 kW may be removed. (author)

  19. Development of industrial-scale fission {sup 99}Mo production process using low enriched uranium target

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Kon; Lee, Jun Sig [Radioisotope Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Beyer, Gerd J. [Grunicke Strasse 15, Leipzig (Germany)

    2016-06-15

    Molybdenum-99 ({sup 99}Mo) is the most important isotope because its daughter isotope, technetium-99m ({sup 99}mTc), has been the most widely used medical radioisotope for more than 50 years, accounting for > 80% of total nuclear diagnostics worldwide. In this review, radiochemical routes for the production of {sup 99}Mo, and the aspects for selecting a suitable process strategy are discussed from the historical viewpoint of {sup 99}Mo technology developments. Most of the industrial-scale {sup 99}Mo processes have been based on the fission of {sup 235}U. Recently, important issues have been raised for the conversion of fission {sup 99}Mo targets from highly enriched uranium to low enriched uranium (LEU). The development of new LEU targets with higher density was requested to compensate for the loss of {sup 99}Mo yield, caused by a significant reduction of {sup 235}U enrichment, from the conversion. As the dramatic increment of intermediate level liquid waste is also expected from the conversion, an effective strategy to reduce the waste generation from the fission {sup 99}Mo production is required. The mitigation of radioxenon emission from medical radioisotope production facilities is discussed in relation with the monitoring of nuclear explosions and comprehensive nuclear test ban. Lastly, the {sup 99}Mo production process paired with the Korea Atomic Energy Research Institute's own LEU target is proposed as one of the most suitable processes for the LEU target.

  20. Hyb-Seq: Combining Target Enrichment and Genome Skimming for Plant Phylogenomics

    Directory of Open Access Journals (Sweden)

    Kevin Weitemier

    2014-08-01

    Full Text Available Premise of the study: Hyb-Seq, the combination of target enrichment and genome skimming, allows simultaneous data collection for low-copy nuclear genes and high-copy genomic targets for plant systematics and evolution studies. Methods and Results: Genome and transcriptome assemblies for milkweed (Asclepias syriaca were used to design enrichment probes for 3385 exons from 768 genes (>1.6 Mbp followed by Illumina sequencing of enriched libraries. Hyb-Seq of 12 individuals (10 Asclepias species and two related genera resulted in at least partial assembly of 92.6% of exons and 99.7% of genes and an average assembly length >2 Mbp. Importantly, complete plastomes and nuclear ribosomal DNA cistrons were assembled using off-target reads. Phylogenomic analyses demonstrated signal conflict between genomes. Conclusions: The Hyb-Seq approach enables targeted sequencing of thousands of low-copy nuclear exons and flanking regions, as well as genome skimming of high-copy repeats and organellar genomes, to efficiently produce genome-scale data sets for phylogenomics.

  1. Hyb-Seq: Combining target enrichment and genome skimming for plant phylogenomics1

    Science.gov (United States)

    Weitemier, Kevin; Straub, Shannon C. K.; Cronn, Richard C.; Fishbein, Mark; Schmickl, Roswitha; McDonnell, Angela; Liston, Aaron

    2014-01-01

    • Premise of the study: Hyb-Seq, the combination of target enrichment and genome skimming, allows simultaneous data collection for low-copy nuclear genes and high-copy genomic targets for plant systematics and evolution studies. • Methods and Results: Genome and transcriptome assemblies for milkweed (Asclepias syriaca) were used to design enrichment probes for 3385 exons from 768 genes (>1.6 Mbp) followed by Illumina sequencing of enriched libraries. Hyb-Seq of 12 individuals (10 Asclepias species and two related genera) resulted in at least partial assembly of 92.6% of exons and 99.7% of genes and an average assembly length >2 Mbp. Importantly, complete plastomes and nuclear ribosomal DNA cistrons were assembled using off-target reads. Phylogenomic analyses demonstrated signal conflict between genomes. • Conclusions: The Hyb-Seq approach enables targeted sequencing of thousands of low-copy nuclear exons and flanking regions, as well as genome skimming of high-copy repeats and organellar genomes, to efficiently produce genome-scale data sets for phylogenomics. PMID:25225629

  2. Development of Industrial-Scale Fission 99Mo Production Process Using Low Enriched Uranium Target

    Directory of Open Access Journals (Sweden)

    Seung-Kon Lee

    2016-06-01

    Full Text Available Molybdenum-99 (99Mo is the most important isotope because its daughter isotope, technetium-99m (99mTc, has been the most widely used medical radioisotope for more than 50 years, accounting for > 80% of total nuclear diagnostics worldwide. In this review, radiochemical routes for the production of 99Mo, and the aspects for selecting a suitable process strategy are discussed from the historical viewpoint of 99Mo technology developments. Most of the industrial-scale 99Mo processes have been based on the fission of 235U. Recently, important issues have been raised for the conversion of fission 99Mo targets from highly enriched uranium to low enriched uranium (LEU. The development of new LEU targets with higher density was requested to compensate for the loss of 99Mo yield, caused by a significant reduction of 235U enrichment, from the conversion. As the dramatic increment of intermediate level liquid waste is also expected from the conversion, an effective strategy to reduce the waste generation from the fission 99Mo production is required. The mitigation of radioxenon emission from medical radioisotope production facilities is discussed in relation with the monitoring of nuclear explosions and comprehensive nuclear test ban. Lastly, the 99Mo production process paired with the Korea Atomic Energy Research Institute's own LEU target is proposed as one of the most suitable processes for the LEU target.

  3. Autoantigens targeted in scleroderma patients with vascular disease are enriched in endothelial lineage cells

    Science.gov (United States)

    McMahan, Zsuzsanna H.; Cottrell, Tricia R.; Wigley, Fredrick M.; Antiochos, Brendan; Zambidis, Elias T.; Park, Tea Soon; Halushka, Marc K.; Gutierrez-Alamillo, Laura; Cimbro, Raffaello; Rosen, Antony; Casciola-Rosen, Livia

    2016-01-01

    Objective Scleroderma patients with autoantibodies to centromere proteins (CENPs) and/or interferon-inducible protein 16 (IFI16) are at increased risk of severe vascular complications. We set out to define whether these autoantigens are enriched in cells of the vasculature. Methods Successive stages of embryoid bodies (EBs) as well as vascular progenitors were used to evaluate the expression of scleroderma autoantigens IFI16 and CENP by immunoblotting. CD31 was included to mark early blood vessels. IFI16 and CD31 expression were defined in skin paraffin sections from scleroderma patients and from healthy controls. IFI16 expression was determined by flow cytometry in circulating endothelial cells (CECs) and circulating progenitor cells (CPCs). Results Expression of CENP-A, IFI16 and CD31 was enriched in EBs at days 10 and 12 of differentiation, and particularly in cultures enriched in vascular progenitors (IFI16, CD31, CENPs A and-B). This pattern was distinct from that of comparator autoantigens. Immunohistochemical staining of skin paraffin sections showed enrichment of IFI16 in CD31-positive vascular endothelial cells in biopsies from scleroderma patients and normal controls. Flow cytometry analysis revealed IFI16 expression in CPCs, but minimal expression in CECs. Conclusion Expression of scleroderma autoantigens IFI16 and CENPs, which are associated with severe vascular disease, is increased in vascular progenitors and mature endothelial cells. High level, lineage-enriched expression of autoantigens may explain the striking association between clinical phenotypes and the immune targeting of specific autoantigens. PMID:27159521

  4. Sampling Enrichment toward Target Structures Using Hybrid Molecular Dynamics-Monte Carlo Simulations.

    Directory of Open Access Journals (Sweden)

    Kecheng Yang

    Full Text Available Sampling enrichment toward a target state, an analogue of the improvement of sampling efficiency (SE, is critical in both the refinement of protein structures and the generation of near-native structure ensembles for the exploration of structure-function relationships. We developed a hybrid molecular dynamics (MD-Monte Carlo (MC approach to enrich the sampling toward the target structures. In this approach, the higher SE is achieved by perturbing the conventional MD simulations with a MC structure-acceptance judgment, which is based on the coincidence degree of small angle x-ray scattering (SAXS intensity profiles between the simulation structures and the target structure. We found that the hybrid simulations could significantly improve SE by making the top-ranked models much closer to the target structures both in the secondary and tertiary structures. Specifically, for the 20 mono-residue peptides, when the initial structures had the root-mean-squared deviation (RMSD from the target structure smaller than 7 Å, the hybrid MD-MC simulations afforded, on average, 0.83 Å and 1.73 Å in RMSD closer to the target than the parallel MD simulations at 310K and 370K, respectively. Meanwhile, the average SE values are also increased by 13.2% and 15.7%. The enrichment of sampling becomes more significant when the target states are gradually detectable in the MD-MC simulations in comparison with the parallel MD simulations, and provide >200% improvement in SE. We also performed a test of the hybrid MD-MC approach in the real protein system, the results showed that the SE for 3 out of 5 real proteins are improved. Overall, this work presents an efficient way of utilizing solution SAXS to improve protein structure prediction and refinement, as well as the generation of near native structures for function annotation.

  5. Differential neutron production cross sections and neutron yields from stopping-length targets for 113-MeV protons

    International Nuclear Information System (INIS)

    Meier, M.M.; Amian, W.B.; Clark, D.A.; Goulding, C.A.; McClelland, J.B.; Morgan, G.L.; Moss, C.E.

    1989-03-01

    We have measured differential (P,ξn) cross sections, d 2 σ/dΩdE/sub n/, from thin targets and absolute neutron yields from stopping-length targets at angles of 7.5/degree/, 30/degree/, 60/degree/, and 150/degree/, for the 113--MeV proton bombardment of elemental beryllium, carbon, aluminum, iron, and depleted uranium. Additional cross-section measurements are reported for oxygen, tungsten, and lead. We used time-of-flight techniques to identify and discriminate against backgrounds and to determine the neutron energy spectrum. Comparison of the experimental data with intranuclear-cascade evaporation-model calculations with the code HETC showed discrepancies as high as a factor of 7 in the differential cross sections. These discrepancies in the differential cross sections make it possible to identify some of the good agreement seen in the stopping-length yield comparisons as fortuitous cancellation of incorrect production estimates in different energy regimes. 13 refs., 20 figs., 4 tabs

  6. Continuing investigations for technology assessment of 99Mo production from LEU [low enriched Uranium] targets

    International Nuclear Information System (INIS)

    Vandergrift, G.F.; Kwok, J.D.; Marshall, S.L.; Vissers, D.R.; Matos, J.E.

    1987-01-01

    Currently much of the world's supply of /sup 99m/Tc for medical purposes is produced from 99 Mo derived from the fissioning of high enriched uranium (HEU). The need for /sup 99m/Tc is continuing to grow, especially in developing countries, where needs and national priorities call for internal production of 99 Mo. This paper presents the results of our continuing studies on the effects of substituting low enriched Uranium (LEU) for HEU in targets for the production of fission product 99 Mo. Improvements in the electrodeposition of thin films of uranium metal are reported. These improvements continue to increase the appeal for the substitution of LEU metal for HEU oxide films in cylindrical targets. The process is effective for targets fabricated from stainless steel or hastaloy. A cost estimate for setting up the necessary equipment to electrodeposit uranium metal on cylindrical targets is reported. Further investigations on the effect of LEU substitution on processing of these targets are also reported. Substitution of uranium silicides for the uranium-aluminum alloy or uranium aluminide dispersed fuel used in other current target designs will allow the substitution of LEU for HEU in these targets with equivalent 99 Mo-yield per target and no change in target geometries. However, this substitution will require modifications in current processing steps due to (1) the insolubility of uranium silicides in alkaline solutions and (2) the presence of significant quantities of silicate in solution. Results to date suggest that both concerns can be handled and that substitution of LEU for HEU can be achieved

  7. Corrosion of target and structural materials in water irradiated by an 800 MeV proton beam

    International Nuclear Information System (INIS)

    Butt, D.P.; Kanner, G.S.; Lillard, R.S.

    1996-01-01

    Radiation enhanced, aqueous corrosion of solid neutron-targets such as tungsten or tantalum, or target cladding or structural materials such as superalloys and stainless steels, is a significant concern in accelerator-driven transmutation technologies. In this paper we briefly describe our current methods for control and in situ monitoring of corrosion in accelerator cooling water loops. Using floating, electrochemical impedance spectroscopy (EIS), we have measured the corrosion rates of aluminum 6061, copper, Inconel 718, and 304L stainless steel in the flow loop of a water target irradiated by a μamp, 800 MeV proton beam. Impedance spectroscopy allows us to model the corrosion process of a material as an equivalent electrical circuit. Thus the polarization resistance, which is inversely proportional to the corrosion rate, can be extracted from the frequency response of a metal specimen. During a three month period, without the use of corrosion mitigation techniques, we observed increases of several orders of magnitude in the water conductivity and the corrosion rates. The increase in corrosion is at least partially attributed to a build up of peroxide in our pseudo-closed loop system. In this paper we also briefly describe our second generation experiments, scheduled to begin in late 1996. In these experiments we plan to measure the corrosion rates of tungsten, tantalum, Inconel 718, 316L and 304L stainless steel, HT-9 austenitic stainless steel, and aluminum 5053. Two or three electrode probes of each material are being placed directly in the proton beam, in a high neutron flux region, or a significant distance from the high radiation area. We will be measuring corrosion rates, changes in pH and conductivity, and we will be establishing parameters for filtration and mitigation of corrosion. We will also discuss our ideas for making in situ measurements of water radiolysis using optical and laser diagnostic techniques

  8. Target-dependent enrichment of virions determines the reduction of high-throughput sequencing in virus discovery.

    Directory of Open Access Journals (Sweden)

    Randi Holm Jensen

    Full Text Available Viral infections cause many different diseases stemming both from well-characterized viral pathogens but also from emerging viruses, and the search for novel viruses continues to be of great importance. High-throughput sequencing is an important technology for this purpose. However, viral nucleic acids often constitute a minute proportion of the total genetic material in a sample from infected tissue. Techniques to enrich viral targets in high-throughput sequencing have been reported, but the sensitivity of such methods is not well established. This study compares different library preparation techniques targeting both DNA and RNA with and without virion enrichment. By optimizing the selection of intact virus particles, both by physical and enzymatic approaches, we assessed the effectiveness of the specific enrichment of viral sequences as compared to non-enriched sample preparations by selectively looking for and counting read sequences obtained from shotgun sequencing. Using shotgun sequencing of total DNA or RNA, viral targets were detected at concentrations corresponding to the predicted level, providing a foundation for estimating the effectiveness of virion enrichment. Virion enrichment typically produced a 1000-fold increase in the proportion of DNA virus sequences. For RNA virions the gain was less pronounced with a maximum 13-fold increase. This enrichment varied between the different sample concentrations, with no clear trend. Despite that less sequencing was required to identify target sequences, it was not evident from our data that a lower detection level was achieved by virion enrichment compared to shotgun sequencing.

  9. Determination of neutron spectra formed by 40-MeV deuteron bombardment of a lithium target with multi-foil activation technique

    CERN Document Server

    Maekawa, F; Wada, M; Wilson, P P H; Ikeda, Y

    2000-01-01

    Neutron flux spectra at an irradiation field produced by a 40-MeV deuteron bombardment on a thick lithium-target at Forschungszentrum Karlsruhe, Germany, have been determined by the multi-foil activation technique. Twenty-seven dosimetry reactions having a wide energy range of threshold energies up to 38 MeV were employed as detectors for the neutron flux spectra extending to 55 MeV. The spectra were adjusted with the SAND-II code with the experimental reaction rates based on an iterative method. The adjusted spectra validated quantitatively the Monte Carlo deuteron-lithium (d-Li) neutron source model code (M sup C DeLi) which was used to calculate initial guess spectra and also has been used for IFMIF nuclear designs. Accuracy of the adjusted spectra was approx 10% that was suitable for successive integral tests of activation cross section data.

  10. Angular distributions of target fragments from the reactions of 292 MeV - 25.2 GeV 12C with 197Au and 238U

    International Nuclear Information System (INIS)

    Morita, Y.

    1983-01-01

    The angular distributions of the 197 Au target fragments were all forwardly peaked. Extensively forward peaked angular distributions were observed at the non-relativistic projectile energies (292 MeV, 1.0 GeV). No obvious differences were observed in the angular distributions at the different relativistic projectile energies of 3.0 GeV, 12.0 GeV and 25.2 GeV. The characteristic angular distribution pattern from the relativistic projectile energy experiments was also observed in the non-relativistic energy experiments. Maximum degree of forward-peaking in the angular distributions at each projectile energy was observed at the product mass number (A) around 190 from the 292 MeV projectile energy, at A = 180 from 1.0 GeV and at A =175 from 3.0 GeV and 12.0 GeV. In general, two different types of angular distributions were observed in the relativistic projectile energy experiments with the 238 U target. Isotropic angular distributions were observed for the fission product nuclides. The angular distributions of the fission products at the intermediate (292 MeV) energy showed slightly forward peaked angular distributions. Because of the long projectile-target interaction time in the primary nuclear reaction, larger momentum was transferred from the projectile to the target nucleus. Steep forward-peaked angular distributions were also observed with the 238 U target

  11. Statistical inference on censored data for targeted clinical trials under enrichment design.

    Science.gov (United States)

    Chen, Chen-Fang; Lin, Jr-Rung; Liu, Jen-Pei

    2013-01-01

    For the traditional clinical trials, inclusion and exclusion criteria are usually based on some clinical endpoints; the genetic or genomic variability of the trial participants are not totally utilized in the criteria. After completion of the human genome project, the disease targets at the molecular level can be identified and can be utilized for the treatment of diseases. However, the accuracy of diagnostic devices for identification of such molecular targets is usually not perfect. Some of the patients enrolled in targeted clinical trials with a positive result for the molecular target might not have the specific molecular targets. As a result, the treatment effect may be underestimated in the patient population truly with the molecular target. To resolve this issue, under the exponential distribution, we develop inferential procedures for the treatment effects of the targeted drug based on the censored endpoints in the patients truly with the molecular targets. Under an enrichment design, we propose using the expectation-maximization algorithm in conjunction with the bootstrap technique to incorporate the inaccuracy of the diagnostic device for detection of the molecular targets on the inference of the treatment effects. A simulation study was conducted to empirically investigate the performance of the proposed methods. Simulation results demonstrate that under the exponential distribution, the proposed estimator is nearly unbiased with adequate precision, and the confidence interval can provide adequate coverage probability. In addition, the proposed testing procedure can adequately control the size with sufficient power. On the other hand, when the proportional hazard assumption is violated, additional simulation studies show that the type I error rate is not controlled at the nominal level and is an increasing function of the positive predictive value. A numerical example illustrates the proposed procedures. Copyright © 2013 John Wiley & Sons, Ltd.

  12. Physics design for the measurement of the ionic emission generated by 12 MeV LIA X-ray converter target

    International Nuclear Information System (INIS)

    Yu Haijun; Long Jidong; Shi Jinshui

    2002-01-01

    Linear induction accelerator (LIA) is expected to generated small diameter x-ray spots with high intensity. The interaction of the electron beam with ions generated at the x-ray converter will make the spot on target increase with time and debase the x-ray dose and the imaging resolving power. The diagnostic methods of ion produced at 12 MeV LIA including faraday cup, sheet diagnostic apparatus and the multiframing interferometer are introduced in the paper

  13. Study of Ne and Kr production in Mg, Al, Rb, Sr and Y targets by 0-180 MeV neutrons. Cosmochemical application

    International Nuclear Information System (INIS)

    Bertin, P.

    1989-07-01

    High sensitivity mass spectrometry technique has been used to measure production of noble gases Ne and Kr induced by 0-180 MeV neutrons in Mg, Al, Rb, Sr and Y targets. This experiment allowed us an evaluation of the implied excitation functions, in an energy range where no experimental data were available. These results have exhibited the importance of secondary neutrons induced in the interaction of cosmic rays with meteorites and moon surface [fr

  14. Microscopic model analyses of proton elastic scattering from diverse targets in the energy range 65 to 400 MeV

    International Nuclear Information System (INIS)

    Dortmans, P.J.; Amos, K.

    1997-01-01

    Two nucleon (NN) effective interactions based upon two-nucleon g matrices have been used in fully microscopic calculations of nonlocal proton-nucleus optical potentials for protons with energies between 65 and 400 MeV. Excellent predictions of the differential cross sections, analysing powers and spin rotations for scattering angles to 60 deg result. (authors)

  15. Correlations between projectile and target breakup: a comparative study of nucleus-nucleus collisions at 75, 175 and 2000A MeV

    International Nuclear Information System (INIS)

    Bjarle, C.; Herrstroem, N.Y.; Kullberg, R.; Oskarsson, A.; Otterlund, I.

    1982-01-01

    Nucleus-nucleus collision in three different energy intervals: 50-100, 150-200 and 1900-2100A MeV have been studied in nuclear emulsion. The reactions were 16 O + average emulsion target (H, C, N, O, Ag, Br). In each event, all emitted charged particles were recorded, projectile fragments with Z>=2 identifed and the number of charged particles from the target nucleus was determined. The results are discussed in terms of the geometrical aspects of Heavy Ion collisions and direct comparisons are made with the Coldhaber fragmentation model

  16. Measurements of attenuation lengths through concrete and iron for neutrons produced by 800-MeV proton on tantalum target at ISIS

    CERN Document Server

    Nunomiya, T; Wright, P; Nakamura, T; Kim, E; Kurosawa, T; Taniguchi, S; Sasaki, M; Iwase, H; Uwamino, Y; Shibata, T; Ito, S; Perry, D R

    2002-01-01

    A deep penetration experiment through a thick bulk shield was performed at an intense spallation neutron source facility, ISIS, of the Rutherford Appleton Laboratory (RAL), United Kingdom. ISIS is a 800 MeV-200 mu A proton accelerator facility. Neutrons are produced from a tantalum target, and are shielded with approximately 3-m thick steel and 1-m thick ordinary concrete. On top of the shield, we measured the neutron flux attenuation through concrete and iron shields, which were additionally placed up to 120-cm and 60-cm thickness, respectively, using activation detectors of graphite and bismuth. The attenuation lengths of concrete and iron for high-energy neutrons above 20 MeV were obtained from the sup 1 sup 2 C(n, 2n) sup 1 sup 1 C reaction of graphite.

  17. Study on the 21 MeV neutron flux characteristics obtained in the 3H(d,n)4He reaction using of gas target

    International Nuclear Information System (INIS)

    Lovchikova, G.N.; Polyakov, A.V.; Sal'nikov, O.A.; Simakov, S.P.; Sukhikh, S.Eh.; Trufanov, A.M.

    1983-01-01

    The possibility to use gas tritium target as neutron source with the energy 2 MeV for nuclear-physical studies has been considered. Characteristics of neutron flux crested in the reaction 3 H(d, n) 4 He to obtain neutrons are investigated. The study of inelastic scattering processes at the energies permits to expand the experiments conducted up to the present day on the study of spectra of inelastically scattered neutrons in a lower energy region and it is of interest for the clarification of appearance mechanism of high-energy neutrons in the spectra. Characteristics of neutron flux as a result of the reaction 3 (α, n) 4 He at the energy of falling deuterons Esub(d)=5.54 MeV are investigated. Measurements of spectra of scattered neutrons on carbon-12 at the angles 30, 45, 60, 90, 120, 150 degrees are made. Differential cross sections of elastic scattering are obtained

  18. Prediction of Effective Drug Combinations by Chemical Interaction, Protein Interaction and Target Enrichment of KEGG Pathways

    Directory of Open Access Journals (Sweden)

    Lei Chen

    2013-01-01

    Full Text Available Drug combinatorial therapy could be more effective in treating some complex diseases than single agents due to better efficacy and reduced side effects. Although some drug combinations are being used, their underlying molecular mechanisms are still poorly understood. Therefore, it is of great interest to deduce a novel drug combination by their molecular mechanisms in a robust and rigorous way. This paper attempts to predict effective drug combinations by a combined consideration of: (1 chemical interaction between drugs, (2 protein interactions between drugs’ targets, and (3 target enrichment of KEGG pathways. A benchmark dataset was constructed, consisting of 121 confirmed effective combinations and 605 random combinations. Each drug combination was represented by 465 features derived from the aforementioned three properties. Some feature selection techniques, including Minimum Redundancy Maximum Relevance and Incremental Feature Selection, were adopted to extract the key features. Random forest model was built with its performance evaluated by 5-fold cross-validation. As a result, 55 key features providing the best prediction result were selected. These important features may help to gain insights into the mechanisms of drug combinations, and the proposed prediction model could become a useful tool for screening possible drug combinations.

  19. Measurement of neutron spectra generated from bombardment of 4 to 24 MeV protons on a thick 9Be target and estimation of neutron yields

    International Nuclear Information System (INIS)

    Paul, Sabyasachi; Sahoo, G. S.; Tripathy, S. P.; Sunil, C.; Bandyopadhyay, T.; Sharma, S. C.; Ramjilal,; Ninawe, N. G.; Gupta, A. K.

    2014-01-01

    A systematic study on the measurement of neutron spectra emitted from the interaction of protons of various energies with a thick beryllium target has been carried out. The measurements were carried out in the forward direction (at 0° with respect to the direction of protons) using CR-39 detectors. The doses were estimated using the in-house image analyzing program autoTRAK-n, which works on the principle of luminosity variation in and around the track boundaries. A total of six different proton energies starting from 4 MeV to 24 MeV with an energy gap of 4 MeV were chosen for the study of the neutron yields and the estimation of doses. Nearly, 92% of the recoil tracks developed after chemical etching were circular in nature, but the size distributions of the recoil tracks were not found to be linearly dependent on the projectile energy. The neutron yield and dose values were found to be increasing linearly with increasing projectile energies. The response of CR-39 detector was also investigated at different beam currents at two different proton energies. A linear increase of neutron yield with beam current was observed

  20. Converting targets and processes for fission-product molybdenum-99 from high- to low-enriched uranium

    International Nuclear Information System (INIS)

    Vandegrift, G.F.; Snelgrove, J.L.; Aase, S.

    1999-01-01

    Most of the world's supply of 99 Mo is produced by the fissioning of 235 U in high-enriched uranium targets (HEU, generally 93% 235 U). To reduce nuclear-proliferation concerns, the U.S. Reduced Enrichment for Research and Test Reactor Program is working to convert the current HEU targets to low-enriched uranium (LEU, 235 U). Switching to LEU targets also requires modifying the separation processes. Current HEU processes can be classified into two main groups based on whether the irradiated target is dissolved in acid or base. Our program has been working on both fronts, with development of targets for acid-side processes being the furthest along. However, using an LEU metal foil target may allow the facile replacement of HEU for both acid and basic dissolution processes. Demonstration of the irradiation and 99 Mo separation processes for the LEU metal-foil targets is being done in cooperation with researchers at the Indonesian PUSPIPTEK facility. We are also developing LEU UO 2 /Al dispersion plates as substitutes for HEU UA1 x /A1 dispersion plates for base-side processes. Results show that conversion to LEU is technically feasible; working with producers is essential to lowering any economic penalty associated with conversion. (author)

  1. Calculation of energy and angular distributions of the bremsstrahlung of 10 MeV electrons bombarding a thick tungsten target

    International Nuclear Information System (INIS)

    Tsovbun, V.I.

    1977-01-01

    Computer calculations have been performed to extend the data available on energy and angular distribution of the 10 MeV electron bremsrahlung into a higher angle region. The ETRAN-16D program developed by R.G.Berger for calculation of electron-photon cascades passing through matter using computers IBM-360 and UNIVAC-1108 was modified to operate with the CDC-6500 computer. A brief summary of the program is provided. An angular distribution of the bremsstrahlung dose absorbed in the air has been also calculated. The results extended into the 90-180 deg region can be used to calculate the biological shield of electron accelerators

  2. Decay patterns of target-like and projectile-like nuclei in 84Kr+197Au, natU reactions at E/A=150 MeV

    International Nuclear Information System (INIS)

    Quednau, B.M.; Galin, J.; Ledoux, X.; Crema, E.; Gebauer, B.; Hilscher, D.; Jahnke, U.; Jacquet, D.; Leray, S.; and others.

    1996-01-01

    The reactions 84 Kr+ 197 Au and 84 Kr+ nat U were studied at E/A=150 MeV employing the large-volume neutron multiplicity filter ORION at SATURNE. The observed correlations between the atomic number of projectile-like nuclei and neutron multiplicity indicate large excitation energies in the primary projectile- and target-like fragments. Angular correlations between the fission fragments of the U-like nucleus and the projectile-like fragments show a memory of the reaction plane, however no indications of spin effects are found. (author)

  3. Development of Genetic Markers in Eucalyptus Species by Target Enrichment and Exome Sequencing

    Science.gov (United States)

    Dasgupta, Modhumita Ghosh; Dharanishanthi, Veeramuthu; Agarwal, Ishangi; Krutovsky, Konstantin V.

    2015-01-01

    The advent of next-generation sequencing has facilitated large-scale discovery, validation and assessment of genetic markers for high density genotyping. The present study was undertaken to identify markers in genes supposedly related to wood property traits in three Eucalyptus species. Ninety four genes involved in xylogenesis were selected for hybridization probe based nuclear genomic DNA target enrichment and exome sequencing. Genomic DNA was isolated from the leaf tissues and used for on-array probe hybridization followed by Illumina sequencing. The raw sequence reads were trimmed and high-quality reads were mapped to the E. grandis reference sequence and the presence of single nucleotide variants (SNVs) and insertions/ deletions (InDels) were identified across the three species. The average read coverage was 216X and a total of 2294 SNVs and 479 InDels were discovered in E. camaldulensis, 2383 SNVs and 518 InDels in E. tereticornis, and 1228 SNVs and 409 InDels in E. grandis. Additionally, SNV calling and InDel detection were conducted in pair-wise comparisons of E. tereticornis vs. E. grandis, E. camaldulensis vs. E. tereticornis and E. camaldulensis vs. E. grandis. This study presents an efficient and high throughput method on development of genetic markers for family– based QTL and association analysis in Eucalyptus. PMID:25602379

  4. Development of genetic markers in Eucalyptus species by target enrichment and exome sequencing.

    Directory of Open Access Journals (Sweden)

    Modhumita Ghosh Dasgupta

    Full Text Available The advent of next-generation sequencing has facilitated large-scale discovery, validation and assessment of genetic markers for high density genotyping. The present study was undertaken to identify markers in genes supposedly related to wood property traits in three Eucalyptus species. Ninety four genes involved in xylogenesis were selected for hybridization probe based nuclear genomic DNA target enrichment and exome sequencing. Genomic DNA was isolated from the leaf tissues and used for on-array probe hybridization followed by Illumina sequencing. The raw sequence reads were trimmed and high-quality reads were mapped to the E. grandis reference sequence and the presence of single nucleotide variants (SNVs and insertions/ deletions (InDels were identified across the three species. The average read coverage was 216X and a total of 2294 SNVs and 479 InDels were discovered in E. camaldulensis, 2383 SNVs and 518 InDels in E. tereticornis, and 1228 SNVs and 409 InDels in E. grandis. Additionally, SNV calling and InDel detection were conducted in pair-wise comparisons of E. tereticornis vs. E. grandis, E. camaldulensis vs. E. tereticornis and E. camaldulensis vs. E. grandis. This study presents an efficient and high throughput method on development of genetic markers for family- based QTL and association analysis in Eucalyptus.

  5. Measurement of neutron activation cross sections in the energy range between 2 and 7 MeV by using a Ti-deuteron target and a deuteron gas target

    Energy Technology Data Exchange (ETDEWEB)

    Senga, T.; Sakane, H.; Shibata, M.; Yamamoto, H.; Kawade, K. [Nagoya Univ. (Japan); Kasugai, Yoshimi; Ikeda, Yujiro; Takeuchi, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2000-03-01

    Using a Ti-deuteron target in the neutron energy range between 2 and 4.5 MeV and a deuteron gas target between 4.5 and 7 MeV, mono-energetic neutrons could be generated enough for activation cross section measurements. The KN-3750 Van de Grraff accelerator at Nagoya University and the Fusion Neutronics Source (FNS) at Japan Atomic Energy Research Institute (JAERI) were used. Preliminary results of activation cross sections were obtained for reactions of {sup 27}Al(n,p){sup 27}Mg, {sup 47}Ti(n,p){sup 47}Sc, {sup 58}Ni(n,p){sup 58}Co. The evaluation data of JENDL-3.2 showed reasonable agreement with our results. (author)

  6. Using targeted enrichment of nuclear genes to increase phylogenetic resolution in the neotropical rain forest genus Inga (Leguminosae: Mimosoideae

    Directory of Open Access Journals (Sweden)

    James A Nicholls

    2015-09-01

    Full Text Available Evolutionary radiations are prominent and pervasive across many plant lineages in diverse geographical and ecological settings; in neotropical rainforests there is growing evidence suggesting that a significant fraction of species richness is the result of recent radiations. Understanding the evolutionary trajectories and mechanisms underlying these radiations demands much greater phylogenetic resolution than is currently available for these groups. The neotropical tree genus Inga (Leguminosae is a good example, with ~300 extant species and a crown age of 2-10 MY, yet over 6kb of plastid and nuclear DNA sequence data gives only poor phylogenetic resolution among species. Here we explore the use of larger-scale nuclear gene data obtained though targeted enrichment to increase phylogenetic resolution within Inga. Transcriptome data from three Inga species were used to select 264 nuclear loci for targeted enrichment and sequencing. Following quality control to remove probable paralogs from these sequence data, the final dataset comprised 259,313 bases from 194 loci for 24 accessions representing 22 Inga species and an outgroup (Zygia. Bayesian phylogenies reconstructed using either all loci concatenated or a subset of 60 loci in a gene-tree/species-tree approach yielded highly resolved phylogenies. We used coalescent approaches to show that the same targeted enrichment data also have significant power to discriminate among alternative within-species population histories in the widespread species I. umbellifera. In either application, targeted enrichment simplifies the informatics challenge of identifying orthologous loci associated with de novo genome sequencing. We conclude that targeted enrichment provides the large volumes of phylogenetically-informative sequence data required to resolve relationships within recent plant species radiations, both at the species level and for within-species phylogeographic studies.

  7. Beam generation and planar imaging at energies below 2.40 MeV with carbon and aluminum linear accelerator targets.

    Science.gov (United States)

    Parsons, David; Robar, James L

    2012-07-01

    Recent work has demonstrated improvement of image quality with low-Z linear accelerator targets and energies as low as 3.5 MV. In this paper, the authors lower the incident electron beam energy between 1.90 and 2.35 MeV and assess the improvement of megavoltage planar image quality with the use of carbon and aluminum linear accelerator targets. The bending magnet shunt current was adjusted in a Varian linear accelerator to allow selection of mean electron energy between 1.90 and 2.35 MeV. Linac set points were altered to increase beam current to allow experimental imaging in a practical time frame. Electron energy was determined through comparison of measured and Monte Carlo modeled depth dose curves. Planar image CNR and spatial resolution measurements were performed to quantify the improvement of image quality. Magnitudes of improvement are explained with reference to Monte Carlo generated energy spectra. After modifications to the linac, beam current was increased by a factor greater than four and incident electron energy was determined to have an adjustable range from 1.90 MeV to 2.35 MeV. CNR of cortical bone was increased by a factor ranging from 6.2 to 7.4 and 3.7 to 4.3 for thin and thick phantoms, respectively, compared to a 6 MV therapeutic beam for both aluminum and carbon targets. Spatial resolution was degraded slightly, with a relative change of 3% and 10% at 0.20 lp∕mm and 0.40 lp∕mm, respectively, when reducing energy from 2.35 to 1.90 MV. The percentage of diagnostic x-rays for the beams examined here, ranges from 46% to 54%. It is possible to produce a large fraction of diagnostic energy x-rays by lowering the beam energy below 2.35 MV. By lowering the beam energy to 1.90 MV or 2.35 MV, CNR improves by factors ranging from 3.7 to 7.4 compared to a 6 MV therapy beam, with only a slight degradation of spatial resolution when lowering the energy from 2.35 MV to 1.90 MV.

  8. Monte Carlo simulations and experimental results on neutron production in the spallation target QUINTA irradiated with 660 MeV protons

    International Nuclear Information System (INIS)

    Khushvaktov, J.H.; Yuldashev, B.S.; Adam, J.; Vrzalova, J.; Baldin, A.A.; Furman, W.I.; Gustov, S.A.; Kish, Yu.V.; Solnyshkin, A.A.; Stegailov, V.I.; Tichy, P.; Tsoupko-Sitnikov, V.M.; Tyutyunnikov, S.I.; Zavorka, L.; Svoboda, J.; Zeman, M.; Vespalec, R.; Wagner, V.

    2017-01-01

    The activation experiment was performed using the accelerated beam of the Phasotron accelerator at the Joint Institute for Nuclear Research (JINR). The natural uranium spallation target QUINTA was irradiated with protons of energy 660 MeV. Monte Carlo simulations were performed using the FLUKA and Geant4 codes. The number of leakage neutrons from the sections of the uranium target surrounded by the lead shielding and the number of leakage neutrons from the lead shield were determined. The total number of fissions in the setup QUINTA were determined. Experimental values of reaction rates for the produced nuclei in the "1"2"7I sample were obtained, and several values of the reaction rates were compared with the results of simulations by the FLUKA and Geant4 codes. The experimentally determined fluence of neutrons in the energy range of 10-200 MeV using the (n, xn) reactions in the "1"2"7I(NaI) sample was compared with the results of simulations. Possibility of transmutation of the long-lived radionuclide "1"2"9I in the QUINTA setup was estimated. [ru

  9. Investigation of selenium compounds as targets for {sup 76,77}Br production using protons of energies up to 34 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, H. Ebrahim [Atomic Energy Authority, Cairo (Egypt). Nuclear Research Centre; Forschungszentrum Juelich (Germany). Inst. fuer Neurowissenschaften und Medizin, INM-5: Nuklearchemie; El-Azony, Khaled M. [Atomic Energy Authority, Cairo (Egypt). Hot Labs. Centre; Azzam, Ahmed [Atomic Energy Authority, Cairo (Egypt). Nuclear Research Centre; Qaim, Syed M. [Forschungszentrum Juelich (Germany). Inst. fuer Neurowissenschaften und Medizin, INM-5: Nuklearchemie

    2017-07-01

    Selenium compounds of Zn, Sn and Cu were prepared using a conventional sintering method and the phase composition of each compound was investigated using X-ray diffraction. The compounds prepared were tested under variable irradiation and separation conditions for {sup 76,77}Br production. The activity of {sup 77}Br was measured as a function of proton beam current within the range 2-15 μA and the thermal stability of the irradiated compound was investigated. The results showed that the compounds ZnSe and Cu{sub 2}Se are thermally more stable in comparison to the SnSe. The effects of several factors, such as temperature, gas flow rate and separation time, were studied to obtain the maximum separation yield of radiobromine by the dry distillation method. The data showed that the compound Cu{sub 2}Se is the most suitable target for proton irradiation to produce {sup 76,77}Br at energies up to 20 MeV. A simplified method was used to prepare also CuSe, which was tested in irradiations with intermediate energy protons of beam currents up to 10 μA. The data of a typical production run using 17 MeV protons and the Cu{sub 2}Se target are reported.

  10. 12C fragmentation at 95 MeV per nucleon for hadron-therapy. Experimental study and simulation with thick PMMA targets

    International Nuclear Information System (INIS)

    Braunn, B.

    2010-11-01

    A study of the 12 C fragmentation at 95 MeV per nucleon on thick PMMA targets is presented on this document. This study is motivated by the development of a new technique for irradiation of malignant tumours: the carbon ion therapy. The purpose of this work is to compare experimental data against nuclear models used in GEANT4 tool-kit. The aim is to determine if the models are sufficiently predictive to the criteria of hadron-therapy. To achieve this goal, a first experiment was performed at GANIL with a 12 C beam at 95 MeV/u and thick PMMA targets. This experiment has achieved the production rates, angular and energy distributions of different fragments produced in nuclear collisions. Comparisons between experimental data and simulated results obtained using the binary intra-nuclear cascade (BIC) and quantum molecular dynamics model (QMD) available in GEANT4 have been performed. These comparisons show the inability of the tested models to reproduce carbon fragmentation at 95 MeV per nucleon with the accuracy required in hadron-therapy. (author)

  11. A Colon Targeted Delivery System for Resveratrol Enriching in pH Responsive-Model

    Directory of Open Access Journals (Sweden)

    Hashem Andishmand, Hamed Hamishehkar, Afshin Babazadeh, Arezou Taghvimi, Mohammad Amin Mohammadifar, Mahnaz Tabibiazar

    2017-03-01

    Full Text Available Background: Resveratrol effects on the prevention and treatment of colon cancer have been well documented recently, but low solubility, rapid absorption and metabolism of resveratrol limit its beneficial effects on colon cancer. Designing a formulation that enhances the solubility of resveratrol, protects resveratrol from oxidation and isomerization, and delivers it to the colon is a priority of food and drug industry. In this study, resveratrol-polyethylene glycol (PEG-loaded pectin-chitosan polyelectrolyte complex was designed as a colon targeted delivery system. Methods: The effects of adding PEG, ultra-sonication time, pH, and pectin to chitosan ratio were investigated on particle size, polydispersity index (PDI, zeta potential by particle size analyzer, and scanning electron microscopy (SEM. Encapsulation efficiency (EE, release of resveratrol in simulated gastrointestinal fluid, and different pHs were analyzed via High Performance Liquid Chromatography (HPLC. Antioxidant activity was measured by (2, 2-diphenyl-1-picryl-hydrazyl-hydrate DPPH free-radical method. Results: Results showed that colloidal stable micro-particles (725 ± 20 nm with PDI < 0.3 and zeta potential +27 ± 2 mV was formed in the ratio of 5:1 of pectin to chitosan w/v % after a 10-min sonication. Encapsulation efficiency was 81 ± 7 %. The reduction of antioxidant activity of resveratrol loaded micro-particles after one month was less than 13%. Micro-particles released about 33% of resveratrol in the simulated gastric and intestinal fluids. Conclusion: Two-thirds of the loaded resveratrol in Pectin-Chitosan complex reached colon. The developed system had enough specification for enriching fruit based drinks due to remarkable colloidal stability in the pH range of 3.5 to 4.5.

  12. The Development of Target-Specific Pose Filter Ensembles To Boost Ligand Enrichment for Structure-Based Virtual Screening.

    Science.gov (United States)

    Xia, Jie; Hsieh, Jui-Hua; Hu, Huabin; Wu, Song; Wang, Xiang Simon

    2017-06-26

    Structure-based virtual screening (SBVS) has become an indispensable technique for hit identification at the early stage of drug discovery. However, the accuracy of current scoring functions is not high enough to confer success to every target and thus remains to be improved. Previously, we had developed binary pose filters (PFs) using knowledge derived from the protein-ligand interface of a single X-ray structure of a specific target. This novel approach had been validated as an effective way to improve ligand enrichment. Continuing from it, in the present work we attempted to incorporate knowledge collected from diverse protein-ligand interfaces of multiple crystal structures of the same target to build PF ensembles (PFEs). Toward this end, we first constructed a comprehensive data set to meet the requirements of ensemble modeling and validation. This set contains 10 diverse targets, 118 well-prepared X-ray structures of protein-ligand complexes, and large benchmarking actives/decoys sets. Notably, we designed a unique workflow of two-layer classifiers based on the concept of ensemble learning and applied it to the construction of PFEs for all of the targets. Through extensive benchmarking studies, we demonstrated that (1) coupling PFE with Chemgauss4 significantly improves the early enrichment of Chemgauss4 itself and (2) PFEs show greater consistency in boosting early enrichment and larger overall enrichment than our prior PFs. In addition, we analyzed the pairwise topological similarities among cognate ligands used to construct PFEs and found that it is the higher chemical diversity of the cognate ligands that leads to the improved performance of PFEs. Taken together, the results so far prove that the incorporation of knowledge from diverse protein-ligand interfaces by ensemble modeling is able to enhance the screening competence of SBVS scoring functions.

  13. Preparation of a liquid nitrogen target for measurement of γ-ray in the 14N(n,γ)15N reaction as an intensity standard in energy region up to 11 MeV

    International Nuclear Information System (INIS)

    Hirano, M.; Obayashi, H.; Sakane, H.; Shibata, M.; Kawade, K.; Taniguchi, A.

    2001-01-01

    For determination of relative γ-ray intensities up to 11 MeV in the 14 N(n,γ) 15 N reaction, we have developed a liquid nitrogen (N 2 ) target which contain no hydrogen (H) to improve the accuracy of γ-ray intensities. The ratio of the relative uncertainties for the liquid nitrogen to that for the melamine (C 3 H 6 N 6 ) widely used was improved by a factor of 2 above 2.2 MeV and a factor of 3 - 6 below 2.2 MeV. It has been shown that the liquid nitrogen target is useful for reduction of the 2.2 MeV γ-ray from the 1 H(n,γ) 2 H reaction and improvement of statistics. (author)

  14. Angular distributions of absorbed dose of Bremsstrahlung and secondary electrons induced by 18-, 28- and 38-MeV electron beams in thick targets.

    Science.gov (United States)

    Takada, Masashi; Kosako, Kazuaki; Oishi, Koji; Nakamura, Takashi; Sato, Kouichi; Kamiyama, Takashi; Kiyanagi, Yoshiaki

    2013-03-01

    Angular distributions of absorbed dose of Bremsstrahlung photons and secondary electrons at a wide range of emission angles from 0 to 135°, were experimentally obtained using an ion chamber with a 0.6 cm(3) air volume covered with or without a build-up cap. The Bremsstrahlung photons and electrons were produced by 18-, 28- and 38-MeV electron beams bombarding tungsten, copper, aluminium and carbon targets. The absorbed doses were also calculated from simulated photon and electron energy spectra by multiplying simulated response functions of the ion chambers, simulated with the MCNPX code. Calculated-to-experimental (C/E) dose ratios obtained are from 0.70 to 1.57 for high-Z targets of W and Cu, from 15 to 135° and the C/E range from 0.6 to 1.4 at 0°; however, the values of C/E for low-Z targets of Al and C are from 0.5 to 1.8 from 0 to 135°. Angular distributions at the forward angles decrease with increasing angles; on the other hand, the angular distributions at the backward angles depend on the target species. The dependences of absorbed doses on electron energy and target thickness were compared between the measured and simulated results. The attenuation profiles of absorbed doses of Bremsstrahlung beams at 0, 30 and 135° were also measured.

  15. Characterization of the energy distribution of neutrons generated by 5 MeV protons on a thick beryllium target at different emission angles

    Energy Technology Data Exchange (ETDEWEB)

    Agosteo, S. [Politecnico di Milano, Dipartimento di Energia, Piazza Leonardo da Vinci 32, 20133 Milano (Italy)] [Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, 20133 Milano (Italy); Colautti, P., E-mail: paolo.colautti@lnl.infn.it [INFN, Laboratori Nazionali di Legnaro (LNL), Via dell' Universita, 2, I-35020 Legnaro (PD) (Italy); Esposito, J., E-mail: juan.esposito@tin.it [INFN, Laboratori Nazionali di Legnaro (LNL), Via dell' Universita, 2, I-35020 Legnaro (PD) (Italy); Fazzi, A.; Introini, M.V.; Pola, A. [Politecnico di Milano, Dipartimento di Energia, Piazza Leonardo da Vinci 32, 20133 Milano (Italy)] [Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, 20133 Milano (Italy)

    2011-12-15

    Neutron energy spectra at different emission angles, between 0 Degree-Sign and 120 Degree-Sign from the Be(p,xn) reaction generated by a beryllium thick-target bombarded with 5 MeV protons, have been measured at the Legnaro Laboratories (LNL) of the Italian National Institute for Nuclear Physics research (INFN). A new and quite compact recoil-proton spectrometer, based on a monolithic silicon telescope, coupled to a polyethylene converter, was efficiently used with respect to the traditional Time-of-Flight (TOF) technique. The measured distributions of recoil-protons were processed through an iterative unfolding algorithm in order to determine the neutron energy spectra at all the angles accounted for. The neutron energy spectrum measured at 0 Degree-Sign resulted to be in good agreement with the only one so far available at the requested energy and measured years ago with TOF technique. Moreover, the results obtained at different emission angles resulted to be consistent with detailed past measurements performed at 4 MeV protons at the same angles by TOF techniques.

  16. Determination of intensity and energy spectrum of neutrons by bombardment of thallium-203 thick target and its copper substrate with 28.5 MeV protons

    International Nuclear Information System (INIS)

    Hajiloo, N.; Raisali, Gh.; Hamidi, S.; Aslani, Gh.

    2007-01-01

    In this research we have determined neutrons spectrum and the intensity that produced from thallium target bombardment. We have applied SRIM and ALICE computer codes to thallium target and its copper substrate for 145 μA of 28.5 MeV incident proton beam from cyclotron Cyclone30. Because of the energy degradation of protons while passing through the thallium target and its copper substrate, the average energy of protons in different depths has been calculated by using SRIM computer code. Then, by applying ALICE computer code for each sub-layer, the neutron production cross sections and their energy spectrum have been calculated to determine the total neutron intensity and spectrum. Using the calculated neutron intensity of 1.22x10 13 n/s as the source, the equivalent dose rate at the distance 6 meters from the target has been calculated by MCNP computer code and the result has been compared with the measured value. The Pb 201 activity has also been calculated as 13.5 Curies. The measured Pb 201 activity by Curie meter CAPINTEC CRC-712 is 13.1 Ci which is in reasonable agreement with the calculated value, bearing in mind the uncertainties in the proposed models and the measurements

  17. The Equilibrium and Pre-equilibrium Triton Emission Spectra of Some Target Nuclei for ( n, xt) Reactions up to 45 MeV Energy

    Science.gov (United States)

    Tel, E.; Kaplan, A.; Aydın, A.; Özkorucuklu, S.; Büyükuslu, H.; Yıldırım, G.

    2010-08-01

    Although there have been significant research and development studies on the inertial and magnetic fusion reactor technology, there is still a long way to go to penetrate commercial fusion reactors to the energy market. Tritium self-sufficiency must be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. So, working out the systematics of ( n,t) reaction cross sections and triton emission differential data are important for the given reaction taking place on various nuclei at different energies. In this study, ( n,xt) reactions for some target nuclei as 16O, 27Al, 59Co and 209Bi have been investigated up to 45 MeV incident neutron energy. In the calculations of the triton emission spectra, the pre-equilibrium and equilibrium effects have been used. The calculated results have been compared with the experimental data taken from the literature.

  18. Collisions of highly stripped ions at MeV energies in gas targets: charge transfer and ionization

    International Nuclear Information System (INIS)

    Schlachter, A.S.

    1980-01-01

    Cross sections have been measured for charge transfer and ionization in H 2 and rare-gas targets by fast, highly ionized carbon, iron, niobium, and lead ions in charge states +3 to +59, with energies in the range 0.1 to 4.8 MeV/amu. Experimental results are compared with classical-trajectory calculations; agreement is generally good. For a given target, the cross sections for net ionization reduce to a common curve when plotted as cross section divided by charge state versus energy per nucleon divided by charge state

  19. An evaluation of different target enrichment methods in pooled sequencing designs for complex disease association studies.

    Directory of Open Access Journals (Sweden)

    Aaron G Day-Williams

    Full Text Available Pooled sequencing can be a cost-effective approach to disease variant discovery, but its applicability in association studies remains unclear. We compare sequence enrichment methods coupled to next-generation sequencing in non-indexed pools of 1, 2, 10, 20 and 50 individuals and assess their ability to discover variants and to estimate their allele frequencies. We find that pooled resequencing is most usefully applied as a variant discovery tool due to limitations in estimating allele frequency with high enough accuracy for association studies, and that in-solution hybrid-capture performs best among the enrichment methods examined regardless of pool size.

  20. Experimental conditions improving in-solution target enrichment for ancient DNA

    DEFF Research Database (Denmark)

    Cruz-Dávalos, Diana I.; Llamas, Bastien; Gaunitz, Charleen

    2017-01-01

    High-throughput sequencing has dramatically fostered ancient DNA research in recent years. Shotgun sequencing, however, does not necessarily appear as the best-suited approach due to the extensive contamination of samples with exogenous environmental microbial DNA. DNA capture-enrichment methods ...

  1. Target preparation by electroplating of enriched thallium-203 and its quality control

    International Nuclear Information System (INIS)

    Al-Rayyes, A. H.; Ailouti, Y.

    2009-02-01

    In this study, the optimum conditions of enriched thallium-203 electroplating on copper holders have been determined starting from different electroplating electrolytes. These conditions include current intensity and thallium concentration. The different solutions were: Newly prepared electrolyte using 203 Tl 2 O 3 , depleted solution used in a previous operations of electroplating, and recovery solutions, coming from Tl-203 separation from lead-201.(author)

  2. Measurement of thick target neutron yield from the reaction (p+181 Ta) with projectiles in the range of 6-20 MeV

    Science.gov (United States)

    Paul, Sabyasachi; Sahoo, G. S.; Tripathy, S. P.; Sharma, S. C.; Joshi, D. S.; Bandyopadhyay, T.

    2018-02-01

    181Ta is a commonly used backing material for many targets in nuclear reaction studies. When the target thickness is less than the range of bombarded projectiles, the interaction via Ta(p,n) reactions in the backing can be a significant source of background. In this study, the neutron spectral yields from the reaction of protons of different energies (between 6 to 20 MeV) with a thick Ta target were determined using CR-39 detectors. The results from this study can be used as a correction factor in such situations. The parameters of registered tracks in CR-39 were analysed using an in-house image analysing program autoTRAK_n and then to derive the associated dose values. The spectral yields obtained experimentally were compared with those obtained from the theoretical calculations. The neutron yield was found to increase with increase in projectile energy mainly due to the opening of reaction channels from (p, n) to (p, 3n).

  3. The new solid target system at UNAM in a self-shielded 11 MeV cyclotron

    International Nuclear Information System (INIS)

    Zarate-Morales, A.; Gaspar-Carcamo, R. E.; Lopez-Rodriguez, V.; Flores-Moreno, A.; Trejo-Ballado, F.; Avila-Rodriguez, Miguel A.

    2012-01-01

    A dual beam line (BL) self-shielded RDS 111 cyclotron for radionuclide production was installed at the School of Medicine of the National Autonomous University of Mexico in 2001. One of the BL’s was upgraded to Eclipse HP (Siemens) in 2008 and the second BL was recently upgraded (June 2011) to the same version with the option for the irradiation of solid targets for the production of metallic radioisotopes.

  4. Secondary electron radiation from different targets exposed to photons with energy 0.1 to 3 MeV

    International Nuclear Information System (INIS)

    Akkerman, A.F.; Botvin, V.A.; Chernov, G.Ya.

    1982-01-01

    Differential and integral yields of secondary electrons from different targets bombarded by monoenergetic photon beams are calculated using the Monte Carlo method. The results are compared to experimental data and values calculated by other authors. The discovered 20 to 30% decrease of calculated backward yields according to experimental data for heavy elements is explained by the limited applicability of Sauter's formula for the description of photoelectron angular distribution. (author)

  5. Monte Carlo modelling and comparison with experiment of the nuclide production in thick stony targets isotropically irradiated with 600 MeV protons

    International Nuclear Information System (INIS)

    Aylmer, D.; Herzog, G.F.; Kruse, T.H.; Cloth, P.; Filges, D.; Moniot, R.K.; Signer, P.; Wieler, R.; Tuniz, C.

    1987-05-01

    Depth profiles for the production of stable and radioactive nuclides have been measured for a large variety of target elements in three thick spherical stony targets with radii of 5, 15 and 26 cm isotropically irradiated with 600 MeV protons at the CERN synchrocyclotron. These irradiation experiments (CERN SC96) were intended to simulate the irradiation of meteoroids by galactic cosmic ray protons. In order to combine this experimental approach with a theoretical one the intra- and internuclear cascades were calculated using Monte Carlo techniques via the high energy transport code HET/KFA 1. Together with transport calculations for low energy neutrons by the MORSE-CG code the depth dependent spectra of primary and secondary protons and of secondary neutrons were derived. On the basis of these spectra and a set of evaluated experimental excitation functions for p-induced reactions and of theoretical ones for n-induced reactions, calculated by the code ALICE LIVERMORE 82, theoretical depth profiles for the production of stable and radioactive nuclides in the three thick targets were calculated. This report is a comprehensive survey on all those target/product combination for which both experimental and theoretical data are available. It provides the basis for a detailed discussion of the various production modes of residual nuclides and on the depth and size dependence of their production rates in thick stony targets, serving as a simulation of the galactic cosmic ray irradiation of meteoroids in space. On the other hand the comparison of the experimental and theoretical depth profiles validates the high energy transport calculations, making them a promissing tool for further model calculations of the interactions of cosmic rays with matter. (orig.)

  6. Low enriched uranium foil targets with different geometries for the production of Molybdenum-99 in the BMR (Brazilian Multipurpose Reactor)

    Energy Technology Data Exchange (ETDEWEB)

    Domingos, Douglas B.; Silva, Antonio T. e; Joao, Thiago G.; Muniz, Rafael O.R.; Coelho, Talita S., E-mail: teixeira@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    A new research reactor is being planned in Brazil to take care of the demand of radiopharmaceuticals in the country and conduct research in various areas. This new reactor, the Brazilian Multipurpose Reactor (RMB), planned for 30 MW, is now in the conception design phase. Two low enriched (<20% {sup 235}U) metallic uranium foil targets (cylinder and plate geometries) are being considered for production of Molybdenum-99 ({sup 99}Mo) by fission. Neutronic and thermal-hydraulics calculations were performed to compare the production of {sup 99}Mo for these targets in the RMB and to determine the temperatures achieved in the targets. For the neutronic calculations were utilized the computer codes HAMMER-TECHNION, CITATION and SCALE and for the thermal-hydraulics calculations were utilized the computer codes MTRCR-IEA-R1 and ANSYS CFX. (author)

  7. Low enriched uranium foil targets with different geometries for the production of Molybdenum-99 in the BMR (Brazilian Multipurpose Reactor)

    International Nuclear Information System (INIS)

    Domingos, Douglas B.; Silva, Antonio T. e; Joao, Thiago G.; Muniz, Rafael O.R.; Coelho, Talita S.

    2011-01-01

    A new research reactor is being planned in Brazil to take care of the demand of radiopharmaceuticals in the country and conduct research in various areas. This new reactor, the Brazilian Multipurpose Reactor (RMB), planned for 30 MW, is now in the conception design phase. Two low enriched ( 235 U) metallic uranium foil targets (cylinder and plate geometries) are being considered for production of Molybdenum-99 ( 99 Mo) by fission. Neutronic and thermal-hydraulics calculations were performed to compare the production of 99 Mo for these targets in the RMB and to determine the temperatures achieved in the targets. For the neutronic calculations were utilized the computer codes HAMMER-TECHNION, CITATION and SCALE and for the thermal-hydraulics calculations were utilized the computer codes MTRCR-IEA-R1 and ANSYS CFX. (author)

  8. Targeted Screening With Combined Age- and Morphology-Based Criteria Enriches Detection of Lynch Syndrome in Endometrial Cancer.

    Science.gov (United States)

    Lin, Douglas I; Hecht, Jonathan L

    2016-06-01

    Endometrial cancer is associated with Lynch syndrome in 2% to 6% of cases. Adequate screening may prevent of a second cancer and incident cancers in family members via risk-reducing strategies. The goal of the study was to evaluate the detection rate of Lynch syndrome via a targeted screening approach. In 2009, we incorporated targeted Lynch syndrome screening via immunohistochemistry for MLH1, PMS2, MSH2, and MSH6, followed by MLH1 promoter hypermethylation, in select cases of endometrial carcinoma. Criteria for patient selection included (1) all patients Lynch syndrome. Therefore, targeted screening with combined age and morphology based criteria enriches detection of Lynch syndrome in endometrial cancer. However, the detection rate is lower than the rates from published series that offer universal screening. © The Author(s) 2016.

  9. The Supply of Medical Radioisotopes. Market impacts of converting to low-enriched uranium targets for medical isotope production

    International Nuclear Information System (INIS)

    Westmacott, Chad; Cameron, Ron

    2012-01-01

    The reliable supply of molybdenum-99 ( 99 Mo) and its decay product, technetium-99m ( 99m Tc), is a vital component of modern medical diagnostic practices. At present, most of the global production of 99 Mo is from highly enriched uranium (HEU) targets. However, all major 99 Mo-producing countries have recently agreed to convert to using low-enriched uranium (LEU) targets to advance important non-proliferation goals, a decision that will have implications for the global supply chain of 99 Mo/ 99m Tc and the long-term supply reliability of these medical isotopes. This study provides the findings and analysis from an extensive examination of the 99 Mo/ 99m Tc supply chain by the OECD/NEA High-level Group on the Security of Supply of Medical Radioisotopes (HLG-MR). It presents a comprehensive evaluation of the potential impacts of converting to the use of LEU targets for 99 Mo production on the global 99 Mo/ 99m Tc market in terms of costs and available production capacity, and the corresponding implications for long-term supply reliability. In this context, the study also briefly discusses the need for policy action by governments in their efforts to ensure a stable and secure long-term supply of 99 Mo/ 99m Tc

  10. Fragmentation and direct transfer reactions for 40Ar incident beam on 27Al target at 1760 MeV

    International Nuclear Information System (INIS)

    Cisse, Ousmane

    1985-01-01

    Peripheral collision studies performed with 40 Ar projectiles at 44 MeV/A and 27 Al target show that both fragmentation and transfer reactions can be discerned in this type of interaction. The experimental observation of fragments with masses charges and velocities close to those of the incident beam are the signature of transfer reactions and a detailed analysis of the energy spectra of such fragments has been carried out and interpreted in terms of a direct diffraction transfer model. On the other hand, for large mass transfer reactions, abrasion is the suitable mechanism. Inclusive fragment measurement together with the appropriate residual nuclei-fragment coincidence results then provides experimental data in good agreement with the theoretical predictions obtained from a participant spectator model. These investigations also indicate that the separation energies of the participant from the spectator nucleus, at least within the framework of the above model, can be interpreted in terms of a friction force which becomes more efficient as the projectile energy decreases. (author) [fr

  11. Measurement of proton induced thick target γ-ray yields on B, N, Na, Al and Si from 2.5 to 4.1 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Chiari, M., E-mail: chiari@fi.infn.it [INFN-Florence and Department of Physics and Astronomy, University of Florence, via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Ferraccioli, G.; Melon, B.; Nannini, A.; Perego, A.; Salvestrini, L. [INFN-Florence and Department of Physics and Astronomy, University of Florence, via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Lagoyannis, A.; Preketes-Sigalas, K. [Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, NCSR “Demokritos”, 153.10 Aghia Paraskevi, Athens (Greece)

    2016-01-01

    Thick target yields for proton induced γ-ray emission (PIGE) on low-Z nuclei, namely B, N, Na, Al and Si, were measured for proton energies from 2.5 to 4.1 MeV and emission angles of 0°, 45° and 90°, at the 3 MV Tandetron laboratory of INFN-LABEC in Florence. The studied reactions were: {sup 10}B(p,α′γ){sup 7}Be (E{sub γ} = 429 keV), {sup 10}B(p,p′γ){sup 10}B (E{sub γ} = 718 keV) and {sup 11}B(p,p′γ){sup 11}B (E{sub γ} = 2125 keV) for boron; {sup 14}N(p,p′γ){sup 14}N (E{sub γ} = 2313 keV) for nitrogen; {sup 23}Na(p,p′γ){sup 23}Na (E{sub γ} = 441 and 1636 keV) and {sup 23}Na(p,α′γ){sup 20}Ne (E{sub γ} = 1634 keV) for sodium; {sup 27}Al(p,p′γ){sup 27}Al (E{sub γ} = 844 and 1014 keV) and {sup 27}Al(p,α′γ){sup 24}Mg (E{sub γ} = 1369 keV) for aluminum; {sup 28}Si(p,p′γ){sup 28}Si (E{sub γ} = 1779 keV) and {sup 29}Si(p,p′γ){sup 29}Si (E{sub γ} = 1273 keV) for silicon. The PIGE thick target yields have been measured with an overall uncertainty typically better than 10%. The use of the measured thick target yield to benchmark and validate experimental cross sections available in the literature is demonstrated.

  12. Attenuation curves in concrete of neutrons from 100 to 400 MeV per nucleon He, C, Ne, Ar, Fe and Xe ions on various targets

    Energy Technology Data Exchange (ETDEWEB)

    Agosteo, S.; Nakamura, T.; Silari, M. E-mail: marco.silari@cern.ch; Zajacova, Z

    2004-04-01

    Data on transmission of neutrons in concrete generated by heavy ions of intermediate energies (of typically up to 1 GeV per nucleon) are of interest for shielding design of accelerators for use in both the research and in the medical field. The energy distributions of neutrons produced by ions of different species (from He to Xe) striking various targets at energies from 100 to 800 MeV per nucleon were recently measured by Kurosawa et al. in the angular range 0-90 deg. . These spectra were used as input data for Monte Carlo simulations to determine source terms and attenuation lengths in ordinary concrete. The present paper presents calculations for 100 MeV/u helium ions on a Cu target, 100 MeV/u carbon ions on C, Al, Cu and Pb, 100 MeV/u neon ions on Cu and Pb, 400 MeV/u carbon ions on C, Al, Cu and Pb, 400 MeV/u neon ions on Cu, 400 MeV/u Ar ions on Cu, 400 MeV/u Fe ions on Cu and 400 MeV/u Xe ions on Cu. The results include the contributions of all secondaries. Some of the resulting attenuation curves are best fitted by a double-exponential function rather than the usual single-exponential. The effect of various approximations introduced in the simulations is discussed. A comparison is made with shielding data for protons scaled with the ion mass number. A comparison is also made with a simple analytical model in use at GANIL.

  13. Mutation intolerant genes and targets of FMRP are enriched for nonsynonymous alleles in schizophrenia.

    Science.gov (United States)

    Leonenko, Ganna; Richards, Alexander L; Walters, James T; Pocklington, Andrew; Chambert, Kimberly; Al Eissa, Mariam M; Sharp, Sally I; O'Brien, Niamh L; Curtis, David; Bass, Nicholas J; McQuillin, Andrew; Hultman, Christina; Moran, Jennifer L; McCarroll, Steven A; Sklar, Pamela; Neale, Benjamin M; Holmans, Peter A; Owen, Michael J; Sullivan, Patrick F; O'Donovan, Michael C

    2017-10-01

    Risk of schizophrenia is conferred by alleles occurring across the full spectrum of frequencies from common SNPs of weak effect through to ultra rare alleles, some of which may be moderately to highly penetrant. Previous studies have suggested that some of the risk of schizophrenia is attributable to uncommon alleles represented on Illumina exome arrays. Here, we present the largest study of exomic variation in schizophrenia to date, using samples from the United Kingdom and Sweden (10,011 schizophrenia cases and 13,791 controls). Single variants, genes, and gene sets were analyzed for association with schizophrenia. No single variant or gene reached genome-wide significance. Among candidate gene sets, we found significant enrichment for rare alleles (minor allele frequency [MAF] schizophrenia by excluding a role for uncommon exomic variants (0.01 ≤ MAF ≥ 0.001) that confer a relatively large effect (odds ratio [OR] > 4). We also show risk alleles within this frequency range exist, but confer smaller effects and should be identified by larger studies. © 2017 Wiley Periodicals, Inc.

  14. Comprehensive profiling of retroviral integration sites using target enrichment methods from historical koala samples without an assembled reference genome

    Directory of Open Access Journals (Sweden)

    Pin Cui

    2016-03-01

    Full Text Available Background. Retroviral integration into the host germline results in permanent viral colonization of vertebrate genomes. The koala retrovirus (KoRV is currently invading the germline of the koala (Phascolarctos cinereus and provides a unique opportunity for studying retroviral endogenization. Previous analysis of KoRV integration patterns in modern koalas demonstrate that they share integration sites primarily if they are related, indicating that the process is currently driven by vertical transmission rather than infection. However, due to methodological challenges, KoRV integrations have not been comprehensively characterized. Results. To overcome these challenges, we applied and compared three target enrichment techniques coupled with next generation sequencing (NGS and a newly customized sequence-clustering based computational pipeline to determine the integration sites for 10 museum Queensland and New South Wales (NSW koala samples collected between the 1870s and late 1980s. A secondary aim of this study sought to identify common integration sites across modern and historical specimens by comparing our dataset to previously published studies. Several million sequences were processed, and the KoRV integration sites in each koala were characterized. Conclusions. Although the three enrichment methods each exhibited bias in integration site retrieval, a combination of two methods, Primer Extension Capture and hybridization capture is recommended for future studies on historical samples. Moreover, identification of integration sites shows that the proportion of integration sites shared between any two koalas is quite small.

  15. Multiplicity of secondary electrons emitted by carbon thin targets by impact of H0, H2+ and H3+ projectiles at MeV energies

    International Nuclear Information System (INIS)

    Vidovic, Zvonimir

    1997-01-01

    This work focuses on the study of the emission statistics of secondary electrons from thin carbon foils bombarded with H 0 , H 2 + and H 3 + projectiles in the 0.25 - 2.2 MeV energy range. The phenomenon of secondary electron emission from solids under the impact of swift ions is mainly due to inelastic interactions with target electrons. Phenomenological and theoretical descriptions as well as a summary of the main theoretical models are the subjects of the first chapter. The experimental set-up used to measure event by event the electron emission of the two faces of the thin carbon foils crossed by an energetic projectile is described in the chapter two. In this chapter there are also presented the method and the algorithms used to process experimental spectra in order to obtain the statistical distribution of the emitted electrons. Chapter three presents the measurements of secondary electron emission induced by H 0 atoms passing through thin carbon foils. The secondary electron yields are studied in correlation with emergent projectile charge state. We show the peculiar role of the projectile electron, whether it remains or not bound to the incident proton. The fourth chapter is dedicated to the secondary electron emission induced by H 2 + and H 3 + polyatomic ions. The results are interpreted in terms of collective effects in the interactions of the ions with solids. The role of the proximity of the protons, molecular ions fragments, upon the amplitude of these collected effects is evidenced from the study of the statistics of forward emission. The experiments allowed us to shed light on various aspects of atom and polyatomic ion interactions with solid surfaces. (author)

  16. Experimental study of deuteron production in α-particle collisions with C, Cu and Pb target nucleus at energies ranging from 200 to 800 A. MeV

    International Nuclear Information System (INIS)

    Montarou, G.

    1988-01-01

    Deuteron production in collisions between alpha-particle and carbon, copper or lead target nuclei at 200, 400, 600 and 800 MeV (Mega-electron Volt) per nucleon have been measured by using the large solid angle detector DIOGENE. Nucleus-nucleus collisions at intermediate energies offer the possibility of studying the properties of highly excited nuclear matter at high density and temperature. Among the different observables measured for the determination of the nuclear matter equation of state, light fragment production measurements has raised considerable interest during the last years because of the close relationship between entropy and nuclear cluster formation. In chapter 1, a general presentation of the main experimental and theoretical aspects of the relativistic heavy ion collision is presented. Chapter 2 is devoted to the description of the detector DIOGENE used at the SATURNE (Saclay-France) accelerator. This detector can measure simultaneously the momenta, masses and emission angles of most of the particles (pions, protons, deuterons ...) emitted in each collision. The chapter 3 describes the method used in order to extract from the raw data the momentum, mass and emission angles of each particle measured in the detector. The deuteron production in central relativistic heavy ion collision is reviewed in chapter 4. Then we present the results of deuteron production measurements, using the DIOGENE detector. In chapter 5 deuteron differential cross-sections are compared with theoretical predictions obtained with intra-nuclear cascade model. In chapter 6 deuteron differential cross-sections are presented for the most central reactions. These spectra are investigated in order to extract the size of the interaction region at the end of the collision. Finally the deuteron-to-proton ratio is studied in relationship with the proton number measured in each event; this ratio is used to evaluate the entropy per nucleon in the most central collisions [fr

  17. A Colon Targeted Delivery System for Resveratrol Enriching in pH Responsive-Model

    DEFF Research Database (Denmark)

    Andishmand, Hashem; Hamishehkar, Hamed; Mohammadifar, Mohammad Amin

    2017-01-01

    Background: Resveratrol effects on the prevention and treatment of colon cancer have been well documented recently, but low solubility, rapid absorption and metabolism of resveratrol limit its beneficial effects on colon cancer. Designing a formulation that enhances the solubility of resveratrol......, protects resveratrol from oxidation and isomerization, and delivers it to the colon is a priority of food and drug industry. In this study, resveratrol-polyethylene glycol (PEG)-loaded pectin-chitosan polyelectrolyte complex was designed as a colon targeted delivery system. Methods: The effects of adding...... PEG, ultra-sonication time, pH, and pectin to chitosan ratio were investigated on particle size, polydispersity index (PDI), zeta potential by particle size analyzer, and scanning electron microscopy (SEM). Encapsulation efficiency (EE), release of resveratrol in simulated gastrointestinal fluid...

  18. Development of low enrichment technologies for high density fuels and for isotope production targets

    International Nuclear Information System (INIS)

    Taboada, Horacio; Gonzalez, Alfredo G.

    2005-01-01

    Since more than twenty years ago, CNEA has carried out RERTR activities. Main goals are to convert the RA 6 reactor core from HEU to LEU, to get a comprehensive understanding of U-Mo/Al compounds phase formation in dispersed and monolithic fuels, to develop possible solutions to VHD dispersed and monolithic fuels technical problems, and to optimize techniques to recover U from silicide scrap samples. The future plans include: 1) Completion the RA 6 reactor conversion to LEU; 2) Qualification by irradiation of the promising solutions found for the high density fuels; 3) Irradiation of mini plates and full scale fuel assemblies at the RA 3 reactor and at higher flux and temperature reactors; 4) Optimization of LEU target and radiochemical techniques for radioisotope production. (author) [es

  19. Elastic and inelastic {alpha}-scattering cross-sections obtained with the 44 MeV fixed energy Saclay cyclotron on separated targets of {sup 24}Mg, {sup 25}Mg, {sup 26}Mg, {sup 40}Ca, {sup 46}Ti, {sup 48}Ti, {sup 50}Ti, {sup 52}Cr, {sup 54}Fe, {sup 56}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu, {sup 65}Cu, {sup 64}Zn, {sup 112}Sn, {sup 114}Sn, {sup 116}Sn, {sup 118}Sn, {sup 120}Sn, {sup 122}Sn, {sup 124}Sn and {sup 208}Pb using the Saclay fixed-energy cyclotron; Sections efficaces differentielles elastiques et inelastiques obtenues par diffusion de particules {alpha} de 44 MeV sur des cibles de {sup 24}Mg, {sup 25}Mg, {sup 26}Mg, {sup 40}Ca, {sup 46}Ti, {sup 48}Ti, {sup 50}Ti, {sup 52}Cr, {sup 54}Fe, {sup 56}Fe, {sup 58}Fe, {sup 58}Ni, {sup 60}Ni, {sup 62}Ni, {sup 64}Ni, {sup 63}Cu, {sup 65}Cu, {sup 64}Zn, {sup 112}Sn, {sup 114}Sn, {sup 116}Sn, {sup 118}Sn, {sup 120}Sn, {sup 122}Sn, {sup 124}Sn et {sup 208}Pb au cyclotron a energie fixe de saclay

    Energy Technology Data Exchange (ETDEWEB)

    Bruge, G [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires. Departement de physique nucleaire, service de physique nucleaire a moyenne energie

    1967-01-01

    This report contains elastic and inelastic {alpha}-scattering cross-sections obtained with the 44 MeV fixed energy Saclay cyclotron on Mg, Ca, Ti, Cr, Fe, Ni, Co, Zn, Sn and Pb enriched targets. (author) [French] Ce rapport contient les tableaux des sections efficaces differentielles obtenues par diffusion elastique et inelastique des particules {alpha} de 44 MeV, fournies par le cyclotron a energie fixe de Saclay, sur des cibles d'isotopes separes de Mg, Ca, Ti, Cr, Fe, Ni, Co, Zn, Sn et Pb. (auteur)

  20. Investigation of thick-target neutron emission from Be-9(d,n)B-10 at E/sub d/ = 7 MeV for angles other than zero degrees

    International Nuclear Information System (INIS)

    Smith, D.L.; Meadows, J.W.; Guenther, P.T.

    1985-01-01

    Double-differential measurements of neutron emission from a thick beryllium target bombarded with 7-MeV deuterons are made for neutrons above 800 keV, over the angular range of 0 to 155 0 . The angular dependence of the neutron yield is found to be quite anisotropic. The importance of this anisotropy in integral neutron-induced reaction cross-section investigations is illustrated. 7 refs.,

  1. A split-target technique in determining the dE/dX of 1.0-5.0 MeV tritium in A1, Ni and Au

    International Nuclear Information System (INIS)

    Labor, M.I.W.

    1986-06-01

    The energy loss of 1.0 to 5.0 MeV tritium in aluminium, nickel and gold have been measured by a split-target technique. The data have been analysed by integrating an analytical expression for the variation of dE/dX with energy. The results are compared with semi-empirical calculations and with previously determined values. (author)

  2. Microscopic model analyses of the elastic scattering of 25, 30, and 40 MeV protons from targets of diverse mass

    International Nuclear Information System (INIS)

    Deb, P.K.; Amos, K.; Karataglidis, S.

    2000-01-01

    An extensive survey and analysis of cross section and analysing power data from proton elastic scattering at energies 25 to 40 MeV is presented. The data are compared with predictions obtained from a full folding specification of the proton-nucleus optical potentials. Isotope and energy variation of the data is explained

  3. Multi-step processes in the (d, t) and (d, 3He) reactions on 116Sn and 208Pb targets at Ed = 200 MeV

    International Nuclear Information System (INIS)

    Langevin-Joliot, H.; Van de Wiele, J.; Guillot, J.; Koning, A.J.

    2000-01-01

    The role of multi-step processes in the reactions 116 Sn(d,t), 208 Pb(d,t) and 116 Sn(d, 3 He), previously studied at E d = 200 MeV at forward angles and for relatively low energy transfers, has been investigated. We have performed for the first time multi-step calculations taking into account systematically collective excitations in the second and higher order step inelastic transitions. A calculation code based on the Feshbach, Kerman and Koonin model has been modified to handle explicitly these collective excitations, most important in the forward angle domain. One step double differential pick-up cross sections were built from finite range distorted wave results spread in energy using known or estimated hole state characteristics. It is shown that two-step cross sections calculated using the above method compare rather well with those deduced via coupled channel calculations for the same collective excitations. The multi-step calculations performed up to 6 steps reproduce reasonably well the 115 Sn, 207 Pb and 115 In experimental spectra measured up to E x ∼- 40 MeV and 15 deg. The relative contributions of steps of increasing order to pick-up cross sections at E d = 200 MeV and 150 MeV are discussed. (authors)

  4. Targeting EphA2-Sam and Its Interactome: Design and Evaluation of Helical Peptides Enriched in Charged Residues.

    Science.gov (United States)

    Mercurio, Flavia A; Marasco, Daniela; Di Natale, Concetta; Pirone, Luciano; Costantini, Susan; Pedone, Emilia M; Leone, Marilisa

    2016-11-17

    The EphA2 receptor controls diverse physiological and pathological conditions and its levels are often upregulated in cancer. Targeting receptor overexpression, through modulation of endocytosis and consequent degradation, appears to be an appealing strategy for attacking tumor malignancy. In this scenario, the Sam domain of EphA2 plays a pivotal role because it is the site where protein regulators of endocytosis and stability are recruited by means of heterotypic Sam-Sam interactions. Because EphA2-Sam heterotypic complexes are largely based on electrostatic contacts, we have investigated the possibility of attacking these interactions with helical peptides enriched in charged residues. Several peptide sequences with high predicted helical propensities were designed, and detailed conformational analyses were conducted by diverse techniques including NMR, CD, and molecular dynamics (MD) simulations. Interaction studies were also performed by NMR, surface plasmon resonance (SPR), and microscale thermophoresis (MST) and led to the identification of two peptides capable of binding to the first Sam domain of Odin. These molecules represent early candidates for the generation of efficient Sam domain binders and antagonists of Sam-Sam interactions involving EphA2. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Literature mining, gene-set enrichment and pathway analysis for target identification in Behçet's disease.

    Science.gov (United States)

    Wilson, Paul; Larminie, Christopher; Smith, Rona

    2016-01-01

    To use literature mining to catalogue Behçet's associated genes, and advanced computational methods to improve the understanding of the pathways and signalling mechanisms that lead to the typical clinical characteristics of Behçet's patients. To extend this technique to identify potential treatment targets for further experimental validation. Text mining methods combined with gene enrichment tools, pathway analysis and causal analysis algorithms. This approach identified 247 human genes associated with Behçet's disease and the resulting disease map, comprising 644 nodes and 19220 edges, captured important details of the relationships between these genes and their associated pathways, as described in diverse data repositories. Pathway analysis has identified how Behçet's associated genes are likely to participate in innate and adaptive immune responses. Causal analysis algorithms have identified a number of potential therapeutic strategies for further investigation. Computational methods have captured pertinent features of the prominent disease characteristics presented in Behçet's disease and have highlighted NOD2, ICOS and IL18 signalling as potential therapeutic strategies.

  6. Elastic and Inelastic α-scatterings from {sup 58}Ni, {sup 116}Sn, and {sup 20}'8Pb targets at 288, 340, 480, and 699 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Behairy, Kassem O., E-mail: drkasemomar@yahoo.com [Physics Department, Aswan University (Egypt); Mahmoud, Zakaria M.M.; Hassanain, M.A. [Physics Department, Faculty of Science, Assiut University (Egypt)

    2015-12-15

    Real double-folding optical potentials are calculated using the S1Y effective nucleon-nucleon (NN) interaction and the tρρ approximation in order to analyze elastic and inelastic scattering of α-particles from {sup 58}Ni, {sup 116}Sn, and {sup 208}Pb targets at 288, 340, 480, and 699 MeV. The relativistic corrections for momenta and reduced masses are performed to investigate the data at the energies 480 and 699 MeV. The second-order (double-scattering) correction to the tρρ potential is also considered. The inelastic scattering to low-lying excited states (2{sup +}) is investigated using the distorted wave born approximation (DWBA) and the coupled-channel (CC) techniques. (author)

  7. Interaction of a 29 MeV 3{sup H}e particle beam with a Cl{sub 4}C vapour target; Interacciones de He{sup 3} de 29 MeV en un blanco de Cl{sub 4}C

    Energy Technology Data Exchange (ETDEWEB)

    Lleo Morilla, A

    1963-07-01

    The interactions of a 29 MeV 3{sup H}e particles beam on a Cl{sub 4}C vapour target have been studied using the photographic method. differential cross-sections for the Cl({sup 3}He, {sup 3}He)Cl elastic scattering and {sup 1}2C({sup 3}He, {alpha}){sup 1}1C pick-up reaction are shown; the corresponding angular distributions in the centre-of-mass system have been compared with the predictions of optical model and A.B.M. theories. (Author) 21 refs.

  8. Polymorphism discovery and allele frequency estimation using high-throughput DNA sequencing of target-enriched pooled DNA samples

    Directory of Open Access Journals (Sweden)

    Mullen Michael P

    2012-01-01

    Full Text Available Abstract Background The central role of the somatotrophic axis in animal post-natal growth, development and fertility is well established. Therefore, the identification of genetic variants affecting quantitative traits within this axis is an attractive goal. However, large sample numbers are a pre-requisite for the identification of genetic variants underlying complex traits and although technologies are improving rapidly, high-throughput sequencing of large numbers of complete individual genomes remains prohibitively expensive. Therefore using a pooled DNA approach coupled with target enrichment and high-throughput sequencing, the aim of this study was to identify polymorphisms and estimate allele frequency differences across 83 candidate genes of the somatotrophic axis, in 150 Holstein-Friesian dairy bulls divided into two groups divergent for genetic merit for fertility. Results In total, 4,135 SNPs and 893 indels were identified during the resequencing of the 83 candidate genes. Nineteen percent (n = 952 of variants were located within 5' and 3' UTRs. Seventy-two percent (n = 3,612 were intronic and 9% (n = 464 were exonic, including 65 indels and 236 SNPs resulting in non-synonymous substitutions (NSS. Significant (P ® MassARRAY. No significant differences (P > 0.1 were observed between the two methods for any of the 43 SNPs across both pools (i.e., 86 tests in total. Conclusions The results of the current study support previous findings of the use of DNA sample pooling and high-throughput sequencing as a viable strategy for polymorphism discovery and allele frequency estimation. Using this approach we have characterised the genetic variation within genes of the somatotrophic axis and related pathways, central to mammalian post-natal growth and development and subsequent lactogenesis and fertility. We have identified a large number of variants segregating at significantly different frequencies between cattle groups divergent for calving

  9. Calculation of proton total reaction cross sections for some target nuclei in incident energy range of 10-600 MeV

    International Nuclear Information System (INIS)

    Bueyuekuslu, H.; Kaplan, A.; Aydin, A.; Tel, E.; Yildirim, G.

    2010-01-01

    In this study, proton total reaction cross sections have been investigated for some isotopes such as 12 C, 27 Al, 9 Be, 16 O, 181 Ta, 197 Au, 6 Li, and 14 N by a proton beam up to 600 MeV. Calculation of the proton total cross sections has been carried out by the analytic expression formulated by M.A. Alvi by using Coulomb-modified Glauber theory with the Helm model nuclear form factor. The obtained results have been discussed and compared with the available experimental data and found to be in agreement with each other.

  10. A Bragg curve counter with an internal production target for the measurement of the double-differential cross-section of fragment production induced by neutrons at energies of tens of MeV

    International Nuclear Information System (INIS)

    Sanami, T.; Hagiwara, M.; Oishi, T.; Hosokawa, M.; Kamada, S.; Tanaka, Su.; Iwamoto, Y.; Nakashima, H.; Baba, M.

    2009-01-01

    A Bragg curve counter equipped with an internal production target was developed for the measurements of double-differential cross-sections of fragment production induced by neutrons at energies of tens of MeV. The internal target permitted a large detection solid angle and thus the registration of processes at low production rates. In this specific geometry, the detection solid angle depends on the emission angle and the range of the particle. Therefore the energy, atomic number, and angle of trajectory of the particle have to be taken into account for the determination of the solid angle. For the selection of events with tracks confined within a defined cylindrical volume around the detector axis, a segmented anode was applied. The double-differential cross-sections for neutron-induced production of lithium, beryllium, and boron fragments from a carbon target were measured at 0 deg. for 65 MeV neutrons. The results are in good agreement with theoretical calculation using PHITS code with GEM and ISOBAR model.

  11. Results of four one-day electron-accelerator irradiations of enriched Mo-100 targets for the production of Mo-99

    Energy Technology Data Exchange (ETDEWEB)

    Chemerisov, S. [Argonne National Lab. (ANL), Argonne, IL (United States); Bailey, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Heltemes, T. [Argonne National Lab. (ANL), Argonne, IL (United States); Jonah, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Makarashvili, V. [Argonne National Lab. (ANL), Argonne, IL (United States); Tkac, P. [Argonne National Lab. (ANL), Argonne, IL (United States); Rotsch, D. [Argonne National Lab. (ANL), Argonne, IL (United States); Virgo, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, G. F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-10-01

    A series of four one-day irradiations was conducted with 100Mo-enriched disk targets. After irradiation, the enriched disks were removed from the target and dissolved. The resulting solution was processed using a NorthStar RadioGenix™ 99mTc generator either at Argonne National Laboratory or at the NorthStar Medical Radioisotopes facility. Runs on the RadioGenix system produced inconsistent analytical results for 99mTc in the Tc/Mo solution. These inconsistencies were attributed to the impurities in the solution or improper column packing. During the irradiations, the performance of the optic transitional radiation (OTR) and infrared cameras was tested in high radiation field. The OTR cameras survived all irradiations, while the IR cameras failed every time. The addition of X-ray and neutron shielding improved camera survivability and decreased the number of upsets.

  12. Charge state and incident energy dependence of K X-ray emission as a function of target thickness for 50-165 MeV Cu ions incident on 11-250 μg/cm2 Cu

    International Nuclear Information System (INIS)

    Momoi, T.; Shima, K.; Umetani, K.; Moriyama, M.; Ishihara, T.; Mikumo, T.

    1986-01-01

    Thin self-supporting Cu targets in 11-250 μg/cm 2 thickness were bombarded with 50-165 MeV Cu sup(qi + ) ions (7 + )+Cu. From the observed K X-ray yields, K-shell vacancy production cross sections averaged over the target thickness t of projectile sigmasub(KV) and target sigmasup(*)sub(KV) were separately derived taking into account the fluorescence yield that can be estimated from the Ksub(α) X-ray energy shift. When the values of sigmasub(KV) and sigmasup(*)sub(KV) are extrapolated to zero foil thickness, the K shell vacancy formed in the collision has been found to be equally shared between projectile and target in a single collision. With the increase of penetration depth, however, the values of sigmasup(*)sub(KV) are greater than those of sigmasub(KV) presumably due to electron transfer of a target K electron to the projectile K vacancy. The evolution process of projectile excited states as a function of target thickness and the resulting variation of projectile and target K X-ray emissions are discussed. (orig.)

  13. Species delimitation and phylogenetic reconstruction of the sinipercids (Perciformes: Sinipercidae) based on target enrichment of thousands of nuclear coding sequences.

    Science.gov (United States)

    Song, Shuli; Zhao, Jinliang; Li, Chenhong

    2017-06-01

    The sinipercids are freshwater fishes endemic to East Asia, mainly in China. Phylogenetic studies on the sinipercids have made great progress in the last decades, but interspecific relationships and evolutionary history of the sinipercids remain unresolved. Lack of distinctive morphological characters leads to problems in validating of some species, such as Siniperca loona. Moreover, genetic data are needed to delimitate species pairs with explicit hypothesis testing, such as in S. chuatsi vs. S. kneri and Coreoperca whiteheadi vs. C. liui. Here we reconstructed phylogeny of the sinipercids with an unprecedented scale of data, 16,943 loci of single-copy coding sequence data from nine sinipercid species, eight putative sister taxa and two outgroups. Targeted sequences were collected using gene enrichment and Illumina sequencing, yielding thousands of protein coding sequences and single nucleotide polymorphisms (SNPs) data. Maximum likelihood and coalescent species tree analyses resulted in identical and highly supported trees. We confirmed that the centrarchids are sister to the sinipercids. A monophyletic Sinipercidae with two genera, Siniperca and Coreoperca was also supported. Different from most previous studies, S. scherzeri was found as the most basal taxon to other species of Siniperca, which consists of two clades: a clade having S. roulei sister to S. chuatsi and S. kneri, and a clade consisting S. loona sister to S. obscura and S. undulata. We found that both S. loona and C. liui are valid species using Bayes factor delimitation (BFD ∗ ) based on SNPs data. Species delimitation also provided decisive support for S. chuatsi and S. kneri being two distinct species. We calibrated a chronogram of the sinipercids based on 100 loci and three fossil calibration points using BEAST, and reconstructed ancestral ranges of the sinipercids using Lagrange Analysis (DEC model) and Statistical Dispersal-Vicariance Analysis (S-DIVA) implemented in RASP. Divergence time

  14. Production yield of produced radioisotopes from 100 MeV proton beam on lead target for shielding analysis of large accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Oranj, Leila Mokhtari; Oh, Joo Hee; Jung, Nam Suk; Bae, O Ryun; Lee, Hee Seock [Div. of Advanced Nuclear Engineering, POSTECH, Pohang (Korea, Republic of)

    2014-11-15

    In this work, the production yield of major shielding material, a lead, was investigated using 100 MeV protons of KOMAC accelerator facility. For the analysis of the experimental data, the activity has been calculated using the FLUKA Monte Carlo code and analytical methods. The cross section data and the stopping power in the irradiated assembly were calculated by TALYS and SRIM codes in the analytical method, respectively. Consequently, the experimental production yield of produced radioisotopes was compared with the data that are based on Monte Carlo calculations and analytical studies. In this research, the {sup nat}Pb(p, x) reaction was studied using experimental measurements, Monte Carlo simulations and analytical methods. Rereading to the experimental measurements, we demonstrate that both Monte Carlo simulation and analytical methods could be useful tools for the estimation of production yield of this reaction.

  15. Production yield of produced radioisotopes from 100 MeV proton beam on lead target for shielding analysis of large accelerator

    International Nuclear Information System (INIS)

    Oranj, Leila Mokhtari; Oh, Joo Hee; Jung, Nam Suk; Bae, O Ryun; Lee, Hee Seock

    2014-01-01

    In this work, the production yield of major shielding material, a lead, was investigated using 100 MeV protons of KOMAC accelerator facility. For the analysis of the experimental data, the activity has been calculated using the FLUKA Monte Carlo code and analytical methods. The cross section data and the stopping power in the irradiated assembly were calculated by TALYS and SRIM codes in the analytical method, respectively. Consequently, the experimental production yield of produced radioisotopes was compared with the data that are based on Monte Carlo calculations and analytical studies. In this research, the nat Pb(p, x) reaction was studied using experimental measurements, Monte Carlo simulations and analytical methods. Rereading to the experimental measurements, we demonstrate that both Monte Carlo simulation and analytical methods could be useful tools for the estimation of production yield of this reaction

  16. Formation of short-lived positron emitters in reactions of protons of energies up to 200 MeV with the target elements carbon, nitrogen and oxygen

    CERN Document Server

    Kettern, K; Qaim, S M; Shubin, Yu N; Steyn, G F; Van der Walt, T N; 10.1016/j.apradiso.2004.02.007

    2004-01-01

    Excitation functions were measured by the stacked-foil technique for proton induced reactions on carbon, nitrogen and oxygen leading to the formation of the short-lived positron emitters /sup 11/C (T/sub 1 /2/=20.38 min) and /sup 13/N (T/sub 1/2/=9.96 min). The energy region covered extended up to 200 MeV. The product activity was measured non-destructively via gamma -ray spectrometry. A careful decay curve analysis of the positron annihilation radiation was invariably performed. The experimental results were compared with theoretical data obtained using the modified hybrid nuclear model code ALICE-IPPE for intermediate energies. The agreement was found to be generally satisfactory. The data are of importance in proton therapy.

  17. Experimental and theoretical study of the yields of residual product nuclei produced in thin targets irradiated by 100-2600 MeV protons

    CERN Document Server

    Titarenko, Y E; Karpikhin, E I

    2003-01-01

    The objective of the project is measurements and computer simulations of independent and cumulative yields of residual product nuclei in thin targets relevant as target materials and structure materials for hybrid accelerator-driven systems coupled to high-energy proton accelerators. The yields of residual product nuclei are of great importance when estimating such basic radiation-technology characteristics of hybrid facility targets as the total target activity, target 'poisoning', buildup of long-lived nuclides that, in turn, are to be transmuted, product nuclide (Po) alpha-activity, content of low-pressure evaporated nuclides (Hg), content of chemically-active nuclides that spoil drastically the corrosion resistance of the facility structure materials, etc. In view of the above, radioactive product nuclide yields from targets and structure materials were determined by an experiment using the ITEP U-10 proton accelerator in 51 irradiation runs for different thin targets: sup 1 sup 8 sup 2 sup , sup 1 sup 8 ...

  18. Measurement of double differential cross sections for light charged particles production in neutron induced reaction at 62.7 MeV on lead target; Mesures des sections efficaces doublement differentielles de production de particules chargees legeres lors de reactions induites par neutrons de 62.7 MeV sur cible de plomb

    Energy Technology Data Exchange (ETDEWEB)

    Kerveno, M

    2000-09-27

    In order to develop new options for nuclear waste management, studies are carrying out on the perfecting of hybrid systems (sub-critical reactor driven by accelerator). This thesis work takes place more precisely in the framework of nuclear data linked to hybrid systems development. Increasing the upper limit energy value (from 20 to 150 MeV) of data bases supposes that theoretical codes could have sufficient predictive power in this energy range. Thus it's necessary to measure new cross sections to constrain these codes. The experiment, performed at Louvain-la-Neuve Cyclotron, aims to determine the double differential cross sections for light charged particles production in neutron induced reactions at 62.7 MeV on natural lead target. The detection device consists of 6 NE102-CsI telescopes. Time of flight measurements are used to reconstruct the neutron energy spectra. The general framework (hybrid systems and associated nuclear data problematic) in which this work takes place is presented in a first part. The experimental set up used for our measurements is described in a second part. The three following parts are dedicated to the data analysis and double differential cross sections extraction. The particle discrimination, the energy calibration of detectors as the different corrections applied to the experimental spectra are related in details. And finally a comparative study between our experimental results and some theoretical predictions is presented. (author)

  19. Measurement of double differential cross sections for light charged particles production in neutron induced reaction at 62.7 MeV on lead target; Mesures des sections efficaces doublement differentielles de production de particules chargees legeres lors de reactions induites par neutrons de 62.7 MeV sur cible de plomb

    Energy Technology Data Exchange (ETDEWEB)

    Kerveno, M

    2000-09-27

    In order to develop new options for nuclear waste management, studies are carrying out on the perfecting of hybrid systems (sub-critical reactor driven by accelerator). This thesis work takes place more precisely in the framework of nuclear data linked to hybrid systems development. Increasing the upper limit energy value (from 20 to 150 MeV) of data bases supposes that theoretical codes could have sufficient predictive power in this energy range. Thus it's necessary to measure new cross sections to constrain these codes. The experiment, performed at Louvain-la-Neuve Cyclotron, aims to determine the double differential cross sections for light charged particles production in neutron induced reactions at 62.7 MeV on natural lead target. The detection device consists of 6 NE102-CsI telescopes. Time of flight measurements are used to reconstruct the neutron energy spectra. The general framework (hybrid systems and associated nuclear data problematic) in which this work takes place is presented in a first part. The experimental set up used for our measurements is described in a second part. The three following parts are dedicated to the data analysis and double differential cross sections extraction. The particle discrimination, the energy calibration of detectors as the different corrections applied to the experimental spectra are related in details. And finally a comparative study between our experimental results and some theoretical predictions is presented. (author)

  20. Analyzing powers and proton spin transfer coefficients in the elastic scattering of 800 MeV polarized protons from an L-type polarized deuteron target at small momentum transfers

    International Nuclear Information System (INIS)

    Adams, D.L.

    1986-10-01

    Analyzing powers and spin transfer coefficients which describe the elastic scattering of polarized protons from a polarized deuteron target have been measured. The energy of the proton beam was 800 MeV and data were taken at laboratory scattering angles of 7, 11, 14, and 16.5 degrees. One analyzing power was also measured at 180 degrees. Three linearly independent orientations of the beam polarization were used and the target was polarized parallel and antiparallel to the direction of the beam momentum. The data were taken with the high resolution spectrometer at the Los Alamos Meson Physics Facility (experiment 685). The results are compared with multiple scattering predictions based on Dirac representations of the nucleon-nucleon scattering matrices. 27 refs., 28 figs., 4 tabs

  1. Comprehensive assessment of sequence variation within the copy number variable defensin cluster on 8p23 by target enriched in-depth 454 sequencing

    Directory of Open Access Journals (Sweden)

    Zhang Xinmin

    2011-05-01

    Full Text Available Abstract Background In highly copy number variable (CNV regions such as the human defensin gene locus, comprehensive assessment of sequence variations is challenging. PCR approaches are practically restricted to tiny fractions, and next-generation sequencing (NGS approaches of whole individual genomes e.g. by the 1000 Genomes Project is confined by an affordable sequence depth. Combining target enrichment with NGS may represent a feasible approach. Results As a proof of principle, we enriched a ~850 kb section comprising the CNV defensin gene cluster DEFB, the invariable DEFA part and 11 control regions from two genomes by sequence capture and sequenced it by 454 technology. 6,651 differences to the human reference genome were found. Comparison to HapMap genotypes revealed sensitivities and specificities in the range of 94% to 99% for the identification of variations. Using error probabilities for rigorous filtering revealed 2,886 unique single nucleotide variations (SNVs including 358 putative novel ones. DEFB CN determinations by haplotype ratios were in agreement with alternative methods. Conclusion Although currently labor extensive and having high costs, target enriched NGS provides a powerful tool for the comprehensive assessment of SNVs in highly polymorphic CNV regions of individual genomes. Furthermore, it reveals considerable amounts of putative novel variations and simultaneously allows CN estimation.

  2. Neutron and proton transmutation-activation cross section libraries to 150 MeV for application in accelerator-driven systems and radioactive ion beam target-design studies

    International Nuclear Information System (INIS)

    Koning, A.J.; Chadwick, M.B.; MacFarlane, R.E.; Mashnik, S.; Wilson, W.B.

    1998-05-01

    New transmutation-activation nuclear data libraries for neutrons and protons up to 150 MeV have been created. These data are important for simulation calculations of radioactivity, and transmutation, in accelerator-driven systems such as the production of tritium (APT) and the transmutation of waste (ATW). They can also be used to obtain cross section predictions for the production of proton-rich isotopes in (p,xn) reactions, for radioactive ion beam (RIB) target-design studies. The nuclear data in these libraries stem from two sources: for neutrons below 20 MeV, we use data from the European activation and transmutation file, EAF97; For neutrons above 20 MeV and for protons at all energies we have isotope production cross sections with the nuclear model code HMS-ALICE. This code applies the Monte Carlo Hybrid Simulation theory, and the Weisskopf-Ewing theory, to calculate cross sections. In a few cases, the HMS-ALICE results were replaced by those calculated using the GNASH code for the Los Alamos LA150 transport library. The resulting two libraries, AF150.N and AF150.P, consist of 766 nuclides each and are represented in the ENDF6-format. An outline is given of the new representation of the data. The libraries have been checked with ENDF6 preprocessing tools and have been processed with NJOY into libraries for the Los Alamos transmutation/radioactivity code CINDER. Numerous benchmark figures are presented for proton-induced excitation functions of various isotopes compared with measurements. Such comparisons are useful for validation purposes, and for assessing the accuracy of the evaluated data. These evaluated libraries are available on the WWW at: http://t2.lanl.gov/. 21 refs

  3. Alginate hydrogel enriched with enamel matrix derivative to target osteogenic cell differentiation in TiO2 scaffolds

    Directory of Open Access Journals (Sweden)

    Helen Pullisaar

    2015-03-01

    Full Text Available The purpose of bone tissue engineering is to employ scaffolds, cells, and growth factors to facilitate healing of bone defects. The aim of this study was to assess the viability and osteogenic differentiation of primary human osteoblasts and adipose tissue–derived mesenchymal stem cells from various donors on titanium dioxide (TiO2 scaffolds coated with an alginate hydrogel enriched with enamel matrix derivative. Cells were harvested for quantitative reverse transcription polymerase chain reaction on days 14 and 21, and medium was collected on days 2, 14, and 21 for protein analyses. Neither coating with alginate hydrogel nor alginate hydrogel enriched with enamel matrix derivative induced a cytotoxic response. Enamel matrix derivative–enriched alginate hydrogel significantly increased the expression of osteoblast markers COL1A1, TNFRSF11B, and BGLAP and secretion of osteopontin in human osteoblasts, whereas osteogenic differentiation of human adipose tissue–derived mesenchymal stem cells seemed unaffected by enamel matrix derivative. The alginate hydrogel coating procedure may have potential for local delivery of enamel matrix derivative and other stimulatory factors for use in bone tissue engineering.

  4. Confirmatory experiments for the United States Department of Energy Accelerator Production of Tritium Program: Neutron, triton and radionuclide production by thick targets of lead and tungsten bombarded by 800 MeV protons

    International Nuclear Information System (INIS)

    Lisowski, P.W.; Cappiello, M.; Ullmann, J.L.; Gavron, A.; King, J.D.; Laird, R.; Mayo, D.; Waters, L.; Zoeller, C.; Staples, P.

    1994-01-01

    Neutron and Triton Production by 800 MeV Protons: The experiments presented in this report were performed in support of the Accelerator Production of Tritium (APT) project at the Los Alamos Weapons Neutron Research (WNR) facility in order to provide data to benchmark and validate physics simulations used in the APT target/blanket design. An experimental apparatus was built that incorporated many of the features of the neutron source region of the 3 He target/blanket. Those features included a tungsten neutron source, flux traps, neutron moderator, lead backstop, lead multiplying annulus, neutron absorbing blanket and a combination neutron de-coupler and tritium producing gas ( 3 He). The experiments were performed in two separate proton irradiations each with approximately 100 nA-hr of 800 MeV protons. The first irradiation was made with a small neutron moderating blanket, allowing the authors to measure tritium production in the 3 He gas by sampling, and counting the amount of tritium. The second irradiation was performed with a large neutron moderating blanket (light water with a 1% manganese sulfate solution) that allowed them to measure both the tritium production in the central region and the total neutron production. The authors did this by sampling and counting the tritium produced and by measuring the activation of the manganese solution. Results of the three tritium production measurements show large disagreements with each other and therefore with the values predicted using the LAHET-MCNP code system. The source of the discrepancies may lie with the sampling system or adsorption on the tungsten surfaces. The authors discuss tests that may resolve that issue. The data for the total neutron production measurement is much more consistent. Those results show excellent agreement between calculation and experiment

  5. Investigation of the formation of residual nuclei from the radiactive .sup.237 Np and .sup.241 Am targets in the reaction with 660-MeV protons

    Czech Academy of Sciences Publication Activity Database

    Adam, Jindřich; Balabekyan, A. R.; Brandt, R.; Dzhelepov, V. P.; Gustov, S. A.; Kalinnikov, V. G.; Krivopustov, M. I.; Mirokhin, I. V.; Mrázek, Jaromír; Odoj, R.

    2002-01-01

    Roč. 65, č. 5 (2002), s. 797-809 ISSN 0044-0027 R&D Projects: GA AV ČR KSK1048102 Keywords : protons * spallation * target activation * radionuclides Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders

  6. Production of iodine-123 radiobiological specimen on 25 MeV electron beam

    International Nuclear Information System (INIS)

    Oganesyan, Yu.Ts.; Starodub, G.Ya.; Buklanov, G.V.; Korotkin, Yu.S.; Belov, A.G.

    1988-01-01

    The technique is described and experimental results are presented for production of radioactive specimen-iodine-123 for medical biological investigations. It is shown that in ten hour irradiation of 124 Xe enriched target of 10 g weight by the 25 MeV electron beam at MT-25 microtron short lived 123 I with activity of about 200 mCl can be accumulated. The procedure was developed for extraction of radioactive atoms and preparing the solution that permits to obtain during 1-1.5 h after the end of irradiation the specimen which satisfies all pharmacopeia requirements. It follows from the results that using small-size electron accelerators with the beam energy up to 25 MeV permits to organize economical and large-scale production of high quality radioactive specimen of 123 I for servicing a large region of this country. 14 refs.; 4 figs.; 1 tab

  7. Experimental thin-target and thick-target yields for natOs(α, xn)Pt, natOs(α, X)Os, Ir and natMo(p, xn)Tc nuclear reactions from threshold up to 38 and 45 MeV, by combined single and stacked foil techniques

    International Nuclear Information System (INIS)

    Birattari, Claudio; Bonardi, Mauro; Gini, Luigi; Groppi, Flavia; Menapace, Enzo

    2002-01-01

    The experimental values of thin-target excitation functions for the nuclear reactions: nat Os(α, X) 188,189,191 Pt, 192g,194m Ir in the energy range 11 - 38 MeV and nat Mo(p, xn) 94g,95g,95m,96(m+g) Tc in the energy range 5 - 44 MeV are presented. The experimental values were obtained by cyclotron activation followed by off-line HPGe γ-spectrometry and corrected at the End Of an Instantaneous Bombardment, EOIB. In different cases use was made of single foil and stacked foil techniques, which present significantly different advantages and disadvantages. The thin-target yield values can be easily either numerically or analytically integrated, as a function of both incoming particle energy and energy loss in target itself, in order to calculate apriori the thick-target yield of various radionuclides under any different experimental condition. Moreover, the thin-target yields are directly related to the effective cross-sections of various nuclear reaction channels involved. The data are of relevant interest for optimizing cyclotron production of platinum and technetium radionuclides to be used as radiotracers for metallo-biochemical, biomedical, toxicological and environmental studies. (author)

  8. Isobaric yields and radiochemistry of near-target residues in the interaction of 12C and 16O with 103Rh at an incident energy of 400 MeV

    International Nuclear Information System (INIS)

    Buthelezi, E.Z.; Steyn, G.F.; Walt, T.N. Van der; Aardaneh, K.; Gadioli, E.; Albertini, F.; Cerutti, F.; Connell, S.H.; Cowley, A.A.; Nortier, F.M.

    2003-01-01

    Production cross sections of residues with mass near to that of the target were measured in 12 C and 16 O induced reactions on Rh at an incident energy of 400 MeV. An ion-exchange method has been developed for the separation of Rh, Pd and Ag nuclides from all other produced activities. Rh and Ag nuclides were separated from elements such as Pd, Ru, and Tc, amongst others, on an AG1-X8 anion exchange resin in 6M HCl. The Ag nuclides were then removed from the effluent using a precipitation technique so that only Rh remained in the final solution. The Pd was afterwards separated from Ru and Tc by eluting it from the resin with 5% ammonia solution. This procedure made it possible to accurately measure production cross sections for 103m Rh and 103 Pd. Cross sections for the production of various other observed residues are also presented. The results are consistent with an enhanced isobaric yield in the near-target mass region. The radiochemical separation technique is also suitable for the routine production of Pd and Rh nuclides, e.g., 103 Pd and 101m Rh, in proton-induced reactions on Rh targets. (author)

  9. Neutron emission from projectile-like and target-like fragments in the 18O+48Ti reaction at E(18O)=116 MeV

    International Nuclear Information System (INIS)

    Chambon, B.; Drain, D.; Pastor, C.; Dauchy, A.; Giorni, A.; Morand, C.

    1982-07-01

    Angular correlations between neutrons and projectile-like fragments detected near the grazing angle were analysed by assuming two incoherent neutrons sources. One source describes slower neutrons evaporated by target-like fragments in equilibrium. The faster, forward-peaked neutrons originate from a second source strongly correlated with the projectile-like fragments with regards to velocity and direction. In some cases neutron emission may even be attributed to known neutron emitter levels in excited ejectiles

  10. Measurement of target fragments produced by 160 MeV proton beam in aluminum and polyethylene with CR-39 plastic nuclear track detectors

    Czech Academy of Sciences Publication Activity Database

    Ambrožová, Iva; Yasuda, N.; Kodaira, S.; Sihver, L.

    2014-01-01

    Roč. 64, MAY (2014), s. 29-34 ISSN 1350-4487 R&D Projects: GA AV ČR KJB100480901; GA AV ČR IAA100480902; GA MŠk LG14004 Institutional support: RVO:61389005 Keywords : target fragments * high-energy protons * Aluminium * Polyethylene * plastic nuclear track detectors * CR-39 Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.213, year: 2014

  11. Uranium enrichment. Enrichment processes

    International Nuclear Information System (INIS)

    Alexandre, M.; Quaegebeur, J.P.

    2009-01-01

    Despite the remarkable progresses made in the diversity and the efficiency of the different uranium enrichment processes, only two industrial processes remain today which satisfy all of enriched uranium needs: the gaseous diffusion and the centrifugation. This article describes both processes and some others still at the demonstration or at the laboratory stage of development: 1 - general considerations; 2 - gaseous diffusion: physical principles, implementation, utilisation in the world; 3 - centrifugation: principles, elementary separation factor, flows inside a centrifuge, modeling of separation efficiencies, mechanical design, types of industrial centrifuges, realisation of cascades, main characteristics of the centrifugation process; 4 - aerodynamic processes: vortex process, nozzle process; 5 - chemical exchange separation processes: Japanese ASAHI process, French CHEMEX process; 6 - laser-based processes: SILVA process, SILMO process; 7 - electromagnetic and ionic processes: mass spectrometer and calutron, ion cyclotron resonance, rotating plasmas; 8 - thermal diffusion; 9 - conclusion. (J.S.)

  12. Experimental and theoretical studies of the yields of residual product nuclei produced in thin Pb and Bi targets irradiated by 40 - 2600 MeV protons

    International Nuclear Information System (INIS)

    Titarenko, Yu. E.; Batyaev, V.F.; Karpikhin, E.I.; Zhivun, V.M.; Ignatyuk, A.V.; Lunev, V.P.; Titarenko, N.N.; Shubin, Yu.N.; Barashenkov, V.S.

    2009-10-01

    The Project is aimed at experimental determining and computer-aided theoretical simulating the independent and cumulative yields of residual radioactive product nuclei in high-energy protonirradiated thin targets made of high-isotopic and natural lead ( 206 Pb, 207 Pb, 208 PB, natPb) and bismuth ( 209 Bi) that are the most probable choice to be the target materials in the acceleratordriven (hybrid) systems (ADS) coupled to a high-current proton accelerator. The yields of residual product nuclei are of great importance when estimating such basic radiation-technology characteristics of the hybrid facility targets as the total target activity, the target 'poisoning', the buildup of long-lived nuclides, the α-activity, the content of low-pressure evaporated nuclides (Hg), the content of the chemically-active nuclides that drastically spoil the corrosion resistance of the facility structure materials, etc. In view of the above, the radioactive product nuclide yields from targets materials were experimentally determined using the ITEP U-10 proton accelerator in 55 measurement runs using the monoisotopic and natural lead ( 206 Pb, 207 Pb, 208 PB, natPb) and bismuth ( 209 Bi) targets within the proton energy range fractionated minutely, namely at 0.04, 0.07, 0.10, 0.8, 1.2, 1.4, 1.6, and 2.6 GeV to cover the entire range of the internuclear hadron cascading. As a result, 5972 cumulative and independent yields of residual radioactive product nuclei, whose lifetimes range from 8 minutes to 32 years, have been measured. Besides, the cross sections for the 27 Al(p,x) 24 Na and 27 Al(p,x)7Be monitor reactions have been measured at the same proton energies together with the 27 Al(n,p) 27 Mg reaction rate that characterizes the neutron background contributions in each experiment. The experimental nuclide yields are determined by the direct γ-spectrometry method. The γ-spectrometer resolution is 1.8 keV in the 1332 keV 60 Co γ-line. The experimental γ-spectra are processed by

  13. Comparison of low enriched uranium (UAlx-Al and U-Ni) targets with different geometries for the production of molybdenum-99 in the RMB (Brazilian multipurpose reactor)

    International Nuclear Information System (INIS)

    Domingos, Douglas B.; Silva, Antonio T. e; Joao, Thiago G.; Silva, Jose Eduardo R. da; Angelo, Gabriel; Fedorenko, Giuliana G.; Nishiyama, Pedro J.B. de O.

    2011-01-01

    The Brazilian Multipurpose Reactor (RMB), now in the conception design phase, is being designed in Brazil to attend the demand of radiopharmaceuticals in the country and conduct researches in various areas. The new reactor, planned for 30 MW, will replace the IEA-R1 reactor of IPEN-CNEN/SP. Low enriched uranium ( 235 U) UAl x dispersed in Al (plate geometry) and metallic uranium foil targets (plate and cylinder geometries) are being considered for production of Molybdenum-99 ( 99 Mo) by fission. Neutronic and thermal-hydraulics calculations were performed to compare the production of 99 Mo for these targets in the RMB. For the neutronic calculations were utilized the computer codes Hammer-Technion, Citation and Scale and for the thermal-hydraulics calculations were utilized the computer code MTRCR-IEAR1 and ANSYS CFX. (author)

  14. Reduced expression of brain-enriched microRNAs in glioblastomas permits targeted regulation of a cell death gene.

    Directory of Open Access Journals (Sweden)

    Rebecca L Skalsky

    Full Text Available Glioblastoma is a highly aggressive malignant tumor involving glial cells in the human brain. We used high-throughput sequencing to comprehensively profile the small RNAs expressed in glioblastoma and non-tumor brain tissues. MicroRNAs (miRNAs made up the large majority of small RNAs, and we identified over 400 different cellular pre-miRNAs. No known viral miRNAs were detected in any of the samples analyzed. Cluster analysis revealed several miRNAs that were significantly down-regulated in glioblastomas, including miR-128, miR-124, miR-7, miR-139, miR-95, and miR-873. Post-transcriptional editing was observed for several miRNAs, including the miR-376 family, miR-411, miR-381, and miR-379. Using the deep sequencing information, we designed a lentiviral vector expressing a cell suicide gene, the herpes simplex virus thymidine kinase (HSV-TK gene, under the regulation of a miRNA, miR-128, that was found to be enriched in non-tumor brain tissue yet down-regulated in glioblastomas, Glioblastoma cells transduced with this vector were selectively killed when cultured in the presence of ganciclovir. Using an in vitro model to recapitulate expression of brain-enriched miRNAs, we demonstrated that neuronally differentiated SH-SY5Y cells transduced with the miRNA-regulated HSV-TK vector are protected from killing by expression of endogenous miR-128. Together, these results provide an in-depth analysis of miRNA dysregulation in glioblastoma and demonstrate the potential utility of these data in the design of miRNA-regulated therapies for the treatment of brain cancers.

  15. Redesign of the Target-Moderator-Reflector-Shield Assembly for Optimization of the Neutron Flux in the 0.001 - 1 MeV at LANSCE

    International Nuclear Information System (INIS)

    Nowicki, Suzanne Florence; Mocko, Michal; Wender, Stephen Arthur; Ferres, Laurent

    2016-01-01

    These are the slides for a presentation at the 2016 Postdoc Summer Seminar Series at Los Alamos National Laboratory. The conclusions of the research presented are the following: we can provide a significant gain in intensity in the upper tier; lower and upper tier are coupled: translating the target in the FOV of the upper tier decreases the intensity in the lower tier; it is possible to balance the production between the upper and lower tier if we keep some of the material between the tiers.

  16. Measurements of the Energy Deposition Profile for 238U Ions with Energy 500 and 950 MEV/U in Stainless Steel and Copper Targets

    CERN Document Server

    Mustafin, Edil; Gnutov, A; Golubev, Alexander; Hofmann, Ingo; Kantsyrev, Alexei; Kunin, Andrey; Latysheva, Ludmila N; Luckjashin, Victor; Panova, Yulia; Schardt, Dieter; Sobolevskiy, Nikolai; Vatulin, Vladimir; Weyrich, Karin

    2005-01-01

    Sub-millimeter wall thickness is foreseen for the vacuum tubes in the magnets of the superconducting dipoles of the SIS100 and SIS300 of the FAIR Project. The Bragg peak of the energy deposition by the U ions in these walls may lie dangerously close to the superconducting cables. Thus the precise knowledge of the dE/dx profile is essential for estimating the heat load by the lost ions in the vicinity of the superconducting wires. Here we present the results of the measurement of the U ion beam energy deposition profile in Cu and stainless steel targets and compare the measured data with the Monte-Carlo simulation using the SHIELD code.

  17. Experimental and theoretical study of radionuclide production on the electronuclear plant target and construction materials irradiated by 1.5 GeV and 130 MeV protons

    International Nuclear Information System (INIS)

    Titarenko, Yu.E.; Karpikhin, E.I.; Smolyakov, A.F.; Igumnov, M.M.; Stepanov, N.V.; Kazaritsky, V.D.; Batyaev, V.F.; Shvedov, O.V.; Mashnik, S.G.; Gabriel, T.A.

    1997-01-01

    Experimental and calculated results are presented for the yields of residual nuclei in 63 Cu, 65 Cu, 206 Pb, 207 Pb, 208 Pb, and 209 Bi targets irradiated to 1.5 GeV and 130 MeV protons and in 59 Co target irradiated to 1.2 GeV protons extracted from the ITEP accelerator. The nuclide yields were found by gamma-spectrometry with a GC-2518 Ge detector, a 1510 module, and a S-100 plate that, as an integral part of IBM PC, emulates a multichannel analyzer. The gamma-spectrometry 60 Co 1332.5 keV line energy resolution was 1.8 keV. The gamma-spectra were processed by the ASPRO code. The SIGMA code with the GDISP radionuclide database was used to identify the gamma-lines and to calculate the respective cross sections. The monitor reactions was 27 Al(p,3pn) 24 Na. The experimental generation cross sections of end products are compared with the respective values calculated by the HETC, INUCL, and CEM95 codes that simulate hadron-nucleus interactions. 12 refs., 3 figs., 7 tabs

  18. Experimental and theoretical study of the residual nuclide production in 40-2600 MeV proton-irradiated thin targets of ads structure materials

    International Nuclear Information System (INIS)

    Titarenko, Yu.E.; Batyaev, V.F.; Belonozhenko, A.A.; Borovlev, S.P.; Butko, M.A.; Florya, S.N.; Pavlov, K.V.; Rogov, V.I.; Tikhonov, R.S.; Titarenko, A.Yu.; Zhivun, V.M.

    2011-10-01

    The Project is aimed at experimental and theoretical studying the independent and cumulative yields of residual radioactive nuclei produced in high-energy proton-irradiated structure materials intended for constructing the high-power Accelerator-Driven Systems (ADS) with a high-current proton accelerator. The Project is an extension of the researches carried out earlier under the ISTC Projects #017, #839, and #2002 which provided more 10000 residual nuclide production cross sections mainly in materials intended to use as target materials of the ADS. This Project includes 57 measurement runs carried out using the 97 targets made only of the ADS structural materials of both monoisotopic ( 56 Fe, 93 Nb, 181 Ta) and natural ( nat Cr, nat Ni, nat W) compositions within minutely fractionated proton energy range, namely, at 0.04, 0.07, 0.1, 0.15, 0.25, 0.4, 0.6, 0.8, 1.2, 1.6 and 2.6GeV. All the targets were irradiated using the ITEP U-10 proton synchrotron. The experimental nuclide yields are determined by the direct γ-spectrometry and α-spectrometry methods. As a result, 3839 cumulative and independent yields of residual β-radioactive product nuclei with lifetimes range from 6 minutes to 10 years as well as 12 cumulative yields of α- radioactive 148 Gd whose lifetime is 74.6 years have been measured. Besides, the cross sections for the 27 Al(p,x) 22 Na , 27 Al(p,x) 24 Na and 27 Al(p,x) 7 Be monitor reactions have been measured at the same proton energies with the use of the current transformer technique. The γ-spectrometer resolution is 1.8 keV in the 1332 keV 60 Co γ-line. The experimental γ-spectra were processed by the GENIE2000 code. The γ-lines were identified, and the cross sections calculated, by the ITEP-developed SIGMA code using the PCNUDAT database. The proton fluence was monitored by the 27 Al(p,x) 22 Na reaction. Measurement data have been compared with the calculation results of the BERTINI and ISABEL models of MCNPX code, CEM03.02, INCL 4.2, INCL4

  19. Integrative ChIP-seq/microarray analysis identifies a CTNNB1 target signature enriched in intestinal stem cells and colon cancer.

    Science.gov (United States)

    Watanabe, Kazuhide; Biesinger, Jacob; Salmans, Michael L; Roberts, Brian S; Arthur, William T; Cleary, Michele; Andersen, Bogi; Xie, Xiaohui; Dai, Xing

    2014-01-01

    Deregulation of canonical Wnt/CTNNB1 (beta-catenin) pathway is one of the earliest events in the pathogenesis of colon cancer. Mutations in APC or CTNNB1 are highly frequent in colon cancer and cause aberrant stabilization of CTNNB1, which activates the transcription of Wnt target genes by binding to chromatin via the TCF/LEF transcription factors. Here we report an integrative analysis of genome-wide chromatin occupancy of CTNNB1 by chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq) and gene expression profiling by microarray analysis upon RNAi-mediated knockdown of CTNNB1 in colon cancer cells. We observed 3629 CTNNB1 binding peaks across the genome and a significant correlation between CTNNB1 binding and knockdown-induced gene expression change. Our integrative analysis led to the discovery of a direct Wnt target signature composed of 162 genes. Gene ontology analysis of this signature revealed a significant enrichment of Wnt pathway genes, suggesting multiple feedback regulations of the pathway. We provide evidence that this gene signature partially overlaps with the Lgr5+ intestinal stem cell signature, and is significantly enriched in normal intestinal stem cells as well as in clinical colorectal cancer samples. Interestingly, while the expression of the CTNNB1 target gene set does not correlate with survival, elevated expression of negative feedback regulators within the signature predicts better prognosis. Our data provide a genome-wide view of chromatin occupancy and gene regulation of Wnt/CTNNB1 signaling in colon cancer cells.

  20. Integrative ChIP-seq/microarray analysis identifies a CTNNB1 target signature enriched in intestinal stem cells and colon cancer.

    Directory of Open Access Journals (Sweden)

    Kazuhide Watanabe

    Full Text Available Deregulation of canonical Wnt/CTNNB1 (beta-catenin pathway is one of the earliest events in the pathogenesis of colon cancer. Mutations in APC or CTNNB1 are highly frequent in colon cancer and cause aberrant stabilization of CTNNB1, which activates the transcription of Wnt target genes by binding to chromatin via the TCF/LEF transcription factors. Here we report an integrative analysis of genome-wide chromatin occupancy of CTNNB1 by chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq and gene expression profiling by microarray analysis upon RNAi-mediated knockdown of CTNNB1 in colon cancer cells.We observed 3629 CTNNB1 binding peaks across the genome and a significant correlation between CTNNB1 binding and knockdown-induced gene expression change. Our integrative analysis led to the discovery of a direct Wnt target signature composed of 162 genes. Gene ontology analysis of this signature revealed a significant enrichment of Wnt pathway genes, suggesting multiple feedback regulations of the pathway. We provide evidence that this gene signature partially overlaps with the Lgr5+ intestinal stem cell signature, and is significantly enriched in normal intestinal stem cells as well as in clinical colorectal cancer samples. Interestingly, while the expression of the CTNNB1 target gene set does not correlate with survival, elevated expression of negative feedback regulators within the signature predicts better prognosis.Our data provide a genome-wide view of chromatin occupancy and gene regulation of Wnt/CTNNB1 signaling in colon cancer cells.

  1. Targeted genomic enrichment and sequencing of CyHV-3 from carp tissues confirms low nucleotide diversity and mixed genotype infections

    Directory of Open Access Journals (Sweden)

    Saliha Hammoumi

    2016-09-01

    Full Text Available Koi herpesvirus disease (KHVD is an emerging disease that causes mass mortality in koi and common carp, Cyprinus carpio L. Its causative agent is Cyprinid herpesvirus 3 (CyHV-3, also known as koi herpesvirus (KHV. Although data on the pathogenesis of this deadly virus is relatively abundant in the literature, still little is known about its genomic diversity and about the molecular mechanisms that lead to such a high virulence. In this context, we developed a new strategy for sequencing full-length CyHV-3 genomes directly from infected fish tissues. Total genomic DNA extracted from carp gill tissue was specifically enriched with CyHV-3 sequences through hybridization to a set of nearly 2 million overlapping probes designed to cover the entire genome length, using KHV-J sequence (GenBank accession number AP008984 as reference. Applied to 7 CyHV-3 specimens from Poland and Indonesia, this targeted genomic enrichment enabled recovery of the full genomes with >99.9% reference coverage. The enrichment rate was directly correlated to the estimated number of viral copies contained in the DNA extracts used for library preparation, which varied between ∼5000 and ∼2×107. The average sequencing depth was >200 for all samples, thus allowing the search for variants with high confidence. Sequence analyses highlighted a significant proportion of intra-specimen sequence heterogeneity, suggesting the presence of mixed infections in all investigated fish. They also showed that inter-specimen genetic diversity at the genome scale was very low (>99.95% of sequence identity. By enabling full genome comparisons directly from infected fish tissues, this new method will be valuable to trace outbreaks rapidly and at a reasonable cost, and in turn to understand the transmission routes of CyHV-3.

  2. Canonical A-to-I and C-to-U RNA editing is enriched at 3'UTRs and microRNA target sites in multiple mouse tissues.

    Directory of Open Access Journals (Sweden)

    Tongjun Gu

    Full Text Available RNA editing is a process that modifies RNA nucleotides and changes the efficiency and fidelity of the central dogma. Enzymes that catalyze RNA editing are required for life, and defects in RNA editing are associated with many diseases. Recent advances in sequencing have enabled the genome-wide identification of RNA editing sites in mammalian transcriptomes. Here, we demonstrate that canonical RNA editing (A-to-I and C-to-U occurs in liver, white adipose, and bone tissues of the laboratory mouse, and we show that apparent non-canonical editing (all other possible base substitutions is an artifact of current high-throughput sequencing technology. Further, we report that high-confidence canonical RNA editing sites can cause non-synonymous amino acid changes and are significantly enriched in 3' UTRs, specifically at microRNA target sites, suggesting both regulatory and functional consequences for RNA editing.

  3. Low enriched uranium UAl{sub X}-Al targets for the production of Molybdenum-99 in the IEA-R1 and RMB reactors

    Energy Technology Data Exchange (ETDEWEB)

    Domingos, Douglas B.; Silva, Antonio T. e; Joao, Thiago G.; Silva, Jose Eduardo R. da, E-mail: teixeira@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Nishiyama, Pedro J.B. de O., E-mail: pedro.julio@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), SP (Brazil)

    2011-07-01

    The IEA-R1 reactor of IPEN/CNEN-SP in Brazil is a pool type research reactor cooled and moderated by demineralized water and having Beryllium and Graphite as reflectors. In 1997 the reactor received the operating licensing for 5 MW. A new research reactor is being planned in Brazil to replace the IEA-R1 reactor. This new reactor, the Brazilian Multipurpose Reactor (RMB), planned for 30 MW, is now in the conception design phase. Low enriched uranium (LEU) (<20% {sup 235}U) UAl{sub x} dispersed in Al targets are being considered for production of Molybdenum-99 ({sup 99}Mo) by fission. Neutronic and thermal-hydraulics calculations were performed, respectively, to compare the production of {sup 99}Mo for these targets in IEA-R1 reactor and RMB and to determine the temperatures achieved in the UAl{sub x}-Al targets during irradiation. For the neutronic calculations were utilized the computer codes HAMMER-TECHNION, CITATION and SCALE and for the thermal-hydraulics calculations was utilized the computer code MTRCR-IEAR1. (author)

  4. Scalability of the LEU-Modified Cintichem Process: 3-MeV Van de Graaff and 35-MeV Electron Linear Accelerator Studies

    Energy Technology Data Exchange (ETDEWEB)

    Rotsch, David A. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Brossard, Tom [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Roussin, Ethan [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Quigley, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Chemerisov, Sergey [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Gromov, Roman [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Jonah, Charles [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Hafenrichter, Lohman [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Tkac, Peter [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Krebs, John [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2016-10-31

    Molybdenum-99, the mother of Tc-99m, can be produced from fission of U-235 in nuclear reactors and purified from fission products by the Cintichem process, later modified for low-enriched uranium (LEU) targets. The key step in this process is the precipitation of Mo with α-benzoin oxime (ABO). The stability of this complex to radiation has been examined. Molybdenum-ABO was irradiated with 3 MeV electrons produced by a Van de Graaff generator and 35 MeV electrons produced by a 50 MeV/25 kW electron linear accelerator. Dose equivalents of 1.7–31.2 kCi of Mo-99 were administered to freshly prepared Mo-ABO. Irradiated samples of Mo-ABO were processed according to the LEU Modified-Cintichem process. The Van de Graaff data indicated good radiation stability of the Mo-ABO complex up to ~15 kCi dose equivalents of Mo-99 and nearly complete destruction at doses >24 kCi Mo-99. The linear accelerator data indicate that even at 6.2 kCi of Mo-99 equivalence of dose, the sample lost ~20% of Mo-99. The 20% loss of Mo-99 at this low dose may be attributed to thermal decomposition of the product from the heat deposited in the sample during irradiation.

  5. An efficient and target-oriented sample enrichment method for preparative separation of minor alkaloids by pH-zone-refining counter-current chromatography.

    Science.gov (United States)

    Feng, Rui-Hong; Hou, Jin-Jun; Zhang, Yi-Bei; Pan, Hui-Qin; Yang, Wenzhi; Qi, Peng; Yao, Shuai; Cai, Lu-Ying; Yang, Min; Jiang, Bao-Hong; Liu, Xuan; Wu, Wan-Ying; Guo, De-An

    2015-08-28

    An efficient and target-oriented sample enrichment method was established to increase the content of the minor alkaloids in crude extract by using the corresponding two-phase solvent system applied in pH-zone-refining counter-current chromatography. The enrichment and separation of seven minor indole alkaloids from Uncaria rhynchophylla (Miq.) Miq. ex Havil(UR) were selected as an example to show the advantage of this method. An optimized two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (3:7:1:9, v/v) was used in this study, where triethylamine (TEA) as the retainer and hydrochloric acid (HCl) as the eluter were added at the equimolar of 10mM. Crude alkaloids of UR dissolved in the corresponding upper phase (containing 10mM TEA) were extracted twice with lower phase (containing 10mM TEA) and lower phase (containing 10mM HCl), respectively, the second lower phase extract was subjected to pH-zone-refining CCC separation after alkalization and desalination. Finally, from 10g of crude alkaloids, 4g of refined alkaloids was obtained and the total content of seven target indole alkaloids was increased from 4.64% to 15.78%. Seven indole alkaloids, including 54mg isocorynoxeine, 21mg corynoxeine, 46mg isorhynchophylline, 35mg rhynchophylline, 65mg hirsutine, 51mg hirsuteine and 27mg geissoschizine methylether were all simultaneously separated from 2.5g of refined alkaloids, with the purity of 86.4%, 97.5%, 90.3%, 92.1%, 98.5%, 92.3%, and 92.8%, respectively. The total content and purities of the seven minor indole alkaloids were tested by HPLC and their chemical structures were elucidated by ESI-HRMS and (1)H NMR. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Alpha particle induced reactions on {sup nat}Cr up to 39 MeV: Experimental cross-sections, comparison with theoretical calculations and thick target yields for medically relevant {sup 52g}Fe production

    Energy Technology Data Exchange (ETDEWEB)

    Hermanne, A.; Adam Rebeles, R. [Cyclotron Laboratory, Vrije Universiteit Brussel, Brussel 1090 (Belgium); Tárkányi, F.; Takács, S. [Institute of Nuclear Research, Hungarian Academy of Science, 4026 Debrecen (Hungary)

    2015-08-01

    Thin {sup nat}Cr targets were obtained by electroplating, using 23.75 μm Cu foils as backings. In five stacked foil irradiations, followed by high resolution gamma spectroscopy, the cross sections for production of {sup 52g}Fe, {sup 49,51cum}Cr, {sup 52cum,54,56cum}Mn and {sup 48cum}V in Cr and {sup 61}Cu,{sup 68}Ga in Cu were measured up to 39 MeV incident α-particle energy. Reduced uncertainty is obtained by simultaneous remeasurement of the {sup nat}Cu(α,x){sup 67,66}Ga monitor reactions over the whole energy range. Comparisons with the scarce literature values and results from the TENDL-2013 on-line library, based on the theoretical code family TALYS-1.6, were made. A discussion of the production routes for {sup 52g}Fe with achievable yields and contamination rates was made.

  7. Targeting Colorectal Cancer Proliferation, Stemness and Metastatic Potential Using Brassicaceae Extracts Enriched in Isothiocyanates: A 3D Cell Model-Based Study

    Directory of Open Access Journals (Sweden)

    Lucília P. Pereira

    2017-04-01

    Full Text Available Colorectal cancer (CRC recurrence is often attributable to circulating tumor cells and/or cancer stem cells (CSCs that resist to conventional therapies and foster tumor progression. Isothiocyanates (ITCs derived from Brassicaceae vegetables have demonstrated anticancer effects in CRC, however little is known about their effect in CSCs and tumor initiation properties. Here we examined the effect of ITCs-enriched Brassicaceae extracts derived from watercress and broccoli in cell proliferation, CSC phenotype and metastasis using a previously developed three-dimensional HT29 cell model with CSC-like traits. Both extracts were phytochemically characterized and their antiproliferative effect in HT29 monolayers was explored. Next, we performed cell proliferation assays and flow cytometry analysis in HT29 spheroids treated with watercress and broccoli extracts and respective main ITCs, phenethyl isothiocyanate (PEITC and sulforaphane (SFN. Soft agar assays and relative quantitative expression analysis of stemness markers and Wnt/β-catenin signaling players were performed to evaluate the effect of these phytochemicals in stemness and metastasis. Our results showed that both Brassicaceae extracts and ITCs exert antiproliferative effects in HT29 spheroids, arresting cell cycle at G2/M, possibly due to ITC-induced DNA damage. Colony formation and expression of LGR5 and CD133 cancer stemness markers were significantly reduced. Only watercress extract and PEITC decreased ALDH1 activity in a dose-dependent manner, as well as β-catenin expression. Our research provides new insights on CRC therapy using ITC-enriched Brassicaceae extracts, specially watercress extract, to target CSCs and circulating tumor cells by impairing cell proliferation, ALDH1-mediated chemo-resistance, anoikis evasion, self-renewal and metastatic potential.

  8. Targeted Enrichment of Large Gene Families for Phylogenetic Inference: Phylogeny and Molecular Evolution of Photosynthesis Genes in the Portullugo Clade (Caryophyllales).

    Science.gov (United States)

    Moore, Abigail J; Vos, Jurriaan M De; Hancock, Lillian P; Goolsby, Eric; Edwards, Erika J

    2018-05-01

    Hybrid enrichment is an increasingly popular approach for obtaining hundreds of loci for phylogenetic analysis across many taxa quickly and cheaply. The genes targeted for sequencing are typically single-copy loci, which facilitate a more straightforward sequence assembly and homology assignment process. However, this approach limits the inclusion of most genes of functional interest, which often belong to multi-gene families. Here, we demonstrate the feasibility of including large gene families in hybrid enrichment protocols for phylogeny reconstruction and subsequent analyses of molecular evolution, using a new set of bait sequences designed for the "portullugo" (Caryophyllales), a moderately sized lineage of flowering plants (~ 2200 species) that includes the cacti and harbors many evolutionary transitions to C$_{\\mathrm{4}}$ and CAM photosynthesis. Including multi-gene families allowed us to simultaneously infer a robust phylogeny and construct a dense sampling of sequences for a major enzyme of C$_{\\mathrm{4}}$ and CAM photosynthesis, which revealed the accumulation of adaptive amino acid substitutions associated with C$_{\\mathrm{4}}$ and CAM origins in particular paralogs. Our final set of matrices for phylogenetic analyses included 75-218 loci across 74 taxa, with ~ 50% matrix completeness across data sets. Phylogenetic resolution was greatly improved across the tree, at both shallow and deep levels. Concatenation and coalescent-based approaches both resolve the sister lineage of the cacti with strong support: Anacampserotaceae $+$ Portulacaceae, two lineages of mostly diminutive succulent herbs of warm, arid regions. In spite of this congruence, BUCKy concordance analyses demonstrated strong and conflicting signals across gene trees. Our results add to the growing number of examples illustrating the complexity of phylogenetic signals in genomic-scale data.

  9. Targeting Colorectal Cancer Proliferation, Stemness and Metastatic Potential Using Brassicaceae Extracts Enriched in Isothiocyanates: A 3D Cell Model-Based Study

    Science.gov (United States)

    Pereira, Lucília P.; Silva, Patrícia; Duarte, Marlene; Rodrigues, Liliana; Duarte, Catarina M. M.; Albuquerque, Cristina; Serra, Ana Teresa

    2017-01-01

    Colorectal cancer (CRC) recurrence is often attributable to circulating tumor cells and/or cancer stem cells (CSCs) that resist to conventional therapies and foster tumor progression. Isothiocyanates (ITCs) derived from Brassicaceae vegetables have demonstrated anticancer effects in CRC, however little is known about their effect in CSCs and tumor initiation properties. Here we examined the effect of ITCs-enriched Brassicaceae extracts derived from watercress and broccoli in cell proliferation, CSC phenotype and metastasis using a previously developed three-dimensional HT29 cell model with CSC-like traits. Both extracts were phytochemically characterized and their antiproliferative effect in HT29 monolayers was explored. Next, we performed cell proliferation assays and flow cytometry analysis in HT29 spheroids treated with watercress and broccoli extracts and respective main ITCs, phenethyl isothiocyanate (PEITC) and sulforaphane (SFN). Soft agar assays and relative quantitative expression analysis of stemness markers and Wnt/β-catenin signaling players were performed to evaluate the effect of these phytochemicals in stemness and metastasis. Our results showed that both Brassicaceae extracts and ITCs exert antiproliferative effects in HT29 spheroids, arresting cell cycle at G2/M, possibly due to ITC-induced DNA damage. Colony formation and expression of LGR5 and CD133 cancer stemness markers were significantly reduced. Only watercress extract and PEITC decreased ALDH1 activity in a dose-dependent manner, as well as β-catenin expression. Our research provides new insights on CRC therapy using ITC-enriched Brassicaceae extracts, specially watercress extract, to target CSCs and circulating tumor cells by impairing cell proliferation, ALDH1-mediated chemo-resistance, anoikis evasion, self-renewal and metastatic potential. PMID:28394276

  10. Isotope enrichment

    International Nuclear Information System (INIS)

    Lydtin, H-J.; Wilden, R.J.; Severin, P.J.W.

    1978-01-01

    The isotope enrichment method described is based on the recognition that, owing to mass diffusion and thermal diffusion in the conversion of substances at a heated substrate while depositing an element or compound onto the substrate, enrichment of the element, or a compound of the element, with a lighter isotope will occur. The cycle is repeated for as many times as is necessary to obtain the degree of enrichment required

  11. Uranium enrichment

    International Nuclear Information System (INIS)

    1990-01-01

    This report looks at the following issues: How much Soviet uranium ore and enriched uranium are imported into the United States and what is the extent to which utilities flag swap to disguise these purchases? What are the U.S.S.R.'s enriched uranium trading practices? To what extent are utilities required to return used fuel to the Soviet Union as part of the enriched uranium sales agreement? Why have U.S. utilities ended their contracts to buy enrichment services from DOE?

  12. Concomitant targeting of multiple key transcription factors effectively disrupts cancer stem cells enriched in side population of human pancreatic cancer cells.

    Directory of Open Access Journals (Sweden)

    Xiyan Wang

    Full Text Available A major challenge in the treatment of pancreatic ductal adenocarcinoma is the failure of chemotherapy, which is likely due to the presence of the cancer stem cells (CSCs.To identify side population (SP cells and characterize s-like properties in human pancreatic cancer cell lines (h-PCCLs and to exploit the efficacy of concomitant targeting of multiple key transcription factors governing the stemness of pancreatic CSCs in suppressing CSC-like phenotypes.Flow cytometry and Hoechst 33342 DNA-binding dye efflux assay were used to sort SP and non-SP (NSP cells from three h-PCCLs: PANC-1, SW1990, and BxPc-3. The self-renewal ability, invasiveness, migration and drug resistance of SP cells were evaluated. Expression of CSC marker genes was analyzed. Tumorigenicity was assessed using a xenograft model in nude mice. Effects of a complex decoy oligonucleotide (cdODN-SCO designed to simultaneously targeting Sox2, Oct4 and c-Myc were assessed.CSCs were enriched in the side proportion (SP cells contained in the h-PCCLs and they possessed aggressive growth, invasion, migration and drug-resistance properties, compared with NSP cells. SP cells overexpressed stem cell markers CD133 and ALDH1, pluripotency maintaining factors Nanog, Sox2 and Oct4, oncogenic transcription factor c-Myc, signaling molecule Notch1, and drug resistant gene ABCG2. Moreover, SP cells consistently demonstrated significantly greater tumorigenicity than NSP cells in xenograft model of nude mice. CdODN-SOC efficiently suppressed all CSC properties and phenotypes, and minimized the tumorigenic capability of the SP cells and the resistance to chemotherapy. By comparison, the negative control failed to do so.The findings indicate that targeting the key genes conferring the stemness of CSCs can efficiently eliminate CSC-like phenotypes, and thus may be considered a new approach for cancer therapy. Specifically, the present study establishes the combination of Sox2/Oct4/c-Myc targeting as a

  13. Novel HIV-1 knockdown targets identified by an enriched kinases/phosphatases shRNA library using a long-term iterative screen in Jurkat T-cells.

    Directory of Open Access Journals (Sweden)

    Sylvie Rato

    2010-02-01

    Full Text Available HIV-1 is a complex retrovirus that uses host machinery to promote its replication. Understanding cellular proteins involved in the multistep process of HIV-1 infection may result in the discovery of more adapted and effective therapeutic targets. Kinases and phosphatases are a druggable class of proteins critically involved in regulation of signal pathways of eukaryotic cells. Here, we focused on the discovery of kinases and phosphatases that are essential for HIV-1 replication but dispensable for cell viability. We performed an iterative screen in Jurkat T-cells with a short-hairpin-RNA (shRNA library highly enriched for human kinases and phosphatases. We identified 14 new proteins essential for HIV-1 replication that do not affect cell viability. These proteins are described to be involved in MAPK, JNK and ERK pathways, vesicular traffic and DNA repair. Moreover, we show that the proteins under study are important in an early step of HIV-1 infection before viral integration, whereas some of them affect viral transcription/translation. This study brings new insights for the complex interplay of HIV-1/host cell and opens new possibilities for antiviral strategies.

  14. Uranium enrichment

    International Nuclear Information System (INIS)

    1989-01-01

    GAO was asked to address several questions concerning a number of proposed uranium enrichment bills introduced during the 100th Congress. The bill would have restructured the Department of Energy's uranium enrichment program as a government corporation to allow it to compete more effectively in the domestic and international markets. Some of GAO's findings discussed are: uranium market experts believe and existing market models show that the proposed DOE purchase of a $750 million of uranium from domestic producers may not significantly increase production because of large producer-held inventories; excess uranium enrichment production capacity exists throughout the world; therefore, foreign producers are expected to compete heavily in the United States throughout the 1990s as utilities' contracts with DOE expire; and according to a 1988 agreement between DOE's Offices of Nuclear Energy and Defense Programs, enrichment decommissioning costs, estimated to total $3.6 billion for planning purposes, will be shared by the commercial enrichment program and the government

  15. Uranium enrichment

    International Nuclear Information System (INIS)

    Rae, H.K.; Melvin, J.G.

    1988-06-01

    Canada is the world's largest producer and exporter of uranium, most of which is enriched elsewhere for use as fuel in LWRs. The feasibility of a Canadian uranium-enrichment enterprise is therefore a perennial question. Recent developments in uranium-enrichment technology, and their likely impacts on separative work supply and demand, suggest an opportunity window for Canadian entry into this international market. The Canadian opportunity results from three particular impacts of the new technologies: 1) the bulk of the world's uranium-enrichment capacity is in gaseous diffusion plants which, because of their large requirements for electricity (more than 2000 kW·h per SWU), are vulnerable to competition from the new processes; 2) the decline in enrichment costs increases the economic incentive for the use of slightly-enriched uranium (SEU) fuel in CANDU reactors, thus creating a potential Canadian market; and 3) the new processes allow economic operation on a much smaller scale, which drastically reduces the investment required for market entry and is comparable with the potential Canadian SEU requirement. The opportunity is not open-ended. By the end of the century the enrichment supply industry will have adapted to the new processes and long-term customer/supplier relationships will have been established. In order to seize the opportunity, Canada must become a credible supplier during this century

  16. Uranium enrichment

    International Nuclear Information System (INIS)

    Mohrhauer, H.

    1982-01-01

    The separation of uranium isotopes in order to enrich the fuel for light water reactors with the light isotope U-235 is an important part of the nuclear fuel cycle. After the basic principals of isotope separation the gaseous diffusion and the centrifuge process are explained. Both these techniques are employed on an industrial scale. In addition a short review is given on other enrichment techniques which have been demonstrated at least on a laboratory scale. After some remarks on the present situation on the enrichment market the progress in the development and the industrial exploitation of the gas centrifuge process by the trinational Urenco-Centec organisation is presented. (orig.)

  17. Multi-step processes in the (d, t) and (d, {sup 3}He) reactions on {sup 116}Sn and {sup 208}Pb targets at E{sub d} = 200 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Langevin-Joliot, H.; Van de Wiele, J.; Guillot, J. [Institut de Physique Nucleaire, IN2P3/CNRS, 91 - Orsay (France); Koning, A.J. [Nuclear Research and Consultancy Group NRG, NL (Netherlands)

    2000-07-01

    The role of multi-step processes in the reactions {sup 116}Sn(d,t), {sup 208}Pb(d,t) and {sup 116}Sn(d,{sup 3}He), previously studied at E{sub d} = 200 MeV at forward angles and for relatively low energy transfers, has been investigated. We have performed for the first time multi-step calculations taking into account systematically collective excitations in the second and higher order step inelastic transitions. A calculation code based on the Feshbach, Kerman and Koonin model has been modified to handle explicitly these collective excitations, most important in the forward angle domain. One step double differential pick-up cross sections were built from finite range distorted wave results spread in energy using known or estimated hole state characteristics. It is shown that two-step cross sections calculated using the above method compare rather well with those deduced via coupled channel calculations for the same collective excitations. The multi-step calculations performed up to 6 steps reproduce reasonably well the {sup 115}Sn, {sup 207}Pb and {sup 115}In experimental spectra measured up to E{sub x}{approx}- 40 MeV and 15 deg. The relative contributions of steps of increasing order to pick-up cross sections at E{sub d} = 200 MeV and 150 MeV are discussed. (authors)

  18. Blueprint for domestic uranium enrichment

    International Nuclear Information System (INIS)

    1981-01-01

    The AEC advisory committee on domestic production of uranium enrichment has studied for more than a year how to achieve the domestic enrichment of uranium by the construction and operation of a commercial enriching plant using centrifugal separation method, and the report was submitted to the Atomic Energy Commission on August 18, 1980. Japan has depended wholly on overseas services for her uranium enrichment needs, but the development of domestic enrichment has been carried on in parallel. The AEC decided to construct a uranium enrichment pilot plant using centrifuges, and it has been forwarded as a national project. The plant is operated by the Power Reactor and Nuclear Fuel Development Corp. since 1979. The capacity of the plant will be raised to approximately 75 ton SWU a year. The centrifuges already operated have provided the first delivery of fuel of about 1 ton for the ATR ''Fugen''. The demand-supply balance of uranium enrichment service, the significance of the domestic enrichment of uranium, the evaluation of uranium enrichment technology, the target for domestic enrichment plan, the measures to promote domestic uranium enrichment, and the promotion of the construction of a demonstration plant are reported. (Kako, I.)

  19. Isotope enrichment

    International Nuclear Information System (INIS)

    Garbuny, M.

    1979-01-01

    The invention discloses a method for deriving, from a starting material including an element having a plurality of isotopes, derived material enriched in one isotope of the element. The starting material is deposited on a substrate at less than a critical submonatomic surface density, typically less than 10 16 atoms per square centimeter. The deposit is then selectively irradiated by a laser (maser or electronic oscillator) beam with monochromatic coherent radiation resonant with the one isotope causing the material including the one istope to escape from the substrate. The escaping enriched material is then collected. Where the element has two isotopes, one of which is to be collected, the deposit may be irradiated with radiation resonant with the other isotope and the residual material enriched in the one isotope may be evaporated from the substrate and collected

  20. Coherent pion production induced by 300 MeV and 600 MeV deuterons

    International Nuclear Information System (INIS)

    Aslanides, E.; Bergdolt, A.M.; Bing, O.; Fassnacht, P.; Hibou, F.

    1982-01-01

    Experimental data on (d,π - ) reactions at 300 and 600 MeV incident energy are presented. Inclusive spectra on 6 Li, 9 Be and 10 B targets near the kinematical limit do not show the usual scaling behaviour. For the two-body reaction 6 Li (d,π - ) 8 B the lowest-energy discrete states of the final nucleus were clearly resolved and the cross sections for pion production leading to those states have been determined. (orig.)

  1. Uranium enrichment

    International Nuclear Information System (INIS)

    1991-08-01

    This paper reports that in 1990 the Department of Energy began a two-year project to illustrate the technical and economic feasibility of a new uranium enrichment technology-the atomic vapor laser isotope separation (AVLIS) process. GAO believes that completing the AVLIS demonstration project will provide valuable information about the technical viability and cost of building an AVLIS plant and will keep future plant construction options open. However, Congress should be aware that DOE still needs to adequately demonstrate AVLIS with full-scale equipment and develop convincing cost projects. Program activities, such as the plant-licensing process, that must be completed before a plant is built, could take many years. Further, an updated and expanded uranium enrichment analysis will be needed before any decision is made about building an AVLIS plant. GAO, which has long supported legislation that would restructure DOE's uranium enrichment program as a government corporation, encourages DOE's goal of transferring AVLIS to the corporation. This could reduce the government's financial risk and help ensure that the decision to build an AVLIS plant is based on commercial concerns. DOE, however, has no alternative plans should the government corporation not be formed. Further, by curtailing a planned public access program, which would have given private firms an opportunity to learn about the technology during the demonstration project, DOE may limit its ability to transfer AVLIS to the private sector

  2. Production of high purity iodine-123 from xenon-124 at energies between 15 and 34 MeV

    International Nuclear Information System (INIS)

    Firouzbakht, M.L.; Teng Renrui; Schlyer, D.J.; Wolf, A.P.

    1987-01-01

    The production of I-123 from the proton bombardment of isotopically enriched Xe-124 is reported over the energy range of 15 to 34 MeV via the 124 Xe (p,pn) 123 Xe (β + , 2.1 hr) → 123 I and 124 Xe (p,2n) 123 Cs (β + , 6 min) → 123 Xe (β + , 2.1 hr) → 123 I pathways. The thick target yields for this target are tabulated and compared to theoretical cross-section calculations of the nuclear reactions leading to the production of Xe-123. The radiochemical purity of the I-123 is greater than 99.9% and the contamination of I-125 is below detectable limits (< 0.1%) at 6.6 hrs after the end of bombardment. (orig.)

  3. MeV Mott polarimetry at Jefferson Lab

    International Nuclear Information System (INIS)

    Steigerwald, M.

    2001-01-01

    In the recent past, Mott polarimetry has been employed only at low electron beam energies (≅100 keV). Shortly after J. Sromicki demonstrated the first Mott scattering experiment on lead foils at 14 MeV (MAMI, 1994), a high energy Mott scattering polarimeter was developed at Thomas Jefferson National Accelerator Facility (5 MeV, 1995). An instrumental precision of 0.5% was achieved due to dramatic improvement in eliminating the background signal by means of collimation, shielding, time of flight and coincidence methods. Measurements for gold targets between 0.05 μm and 5 μm for electron energies between 2 and 8 MeV are presented. A model was developed to explain the depolarization effects in the target foils due to double scattering. The instrumental helicity correlated asymmetries were measured to smaller than 0.1%

  4. Excitation function of (p,α) nuclear reaction on enriched {sup 67}Zn. Possibility of production of {sup 64}Cu at low energy cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Szelecsenyi, Ferenc; Kovacs, Zoltan [Hungarian Academy of Sciences, Debrecen (Hungary). Cyclotron Application Dept.; Nagatsu, Kotaro; Zhang, Ming-Rong; Suzuki, Kazutosi [National Institute of Radiological Sciences, Chiba (Japan). Molecular Imaging Center

    2014-09-01

    The potential for production of the medically relevant {sup 64}Cu has been investigated by proton irradiation of highly enriched {sup 67}Zn targets. The excitation function of the {sup 67}Zn(p,α){sup 64}Cu a nuclear reaction was measured by the stacked-foil technique up to 30 MeV. The prediction of the TALYS code was also compared to the measured cross section results. Based on the improved database of the {sup 67}Zn(p,α){sup 64}Cu reaction, thick target yield as a function of energy was also deduced. Production possibility of {sup 64}Cu is discussed in detail, employing different energy proton beams and with regards to the {sup 61}Cu and {sup 67}Cu contamination levels as a function of the target enrichment level. By using 1 μA beam intensity, 6.3505 h irradiation time and enriched {sup 67}Zn target ({sup 64}Zn ≤ 0.5%, {sup 66}Zn ≤ 9%, {sup 67}Zn ≥ 80%, {sup 68}Zn ≤ 10% and {sup 70}Zn ≤ 0.5%), the expected EOB (End Of bombardment) yields are 43.66, 88.80 and 156.14MBq/μA at 12, 15 and 18 MeV proton energies, respectively. Application time-frames were also deduced where the total radio-copper contamination level remains below 1%. (orig.)

  5. Accelerated Homology-Directed Targeted Integration of Transgenes in Chinese Hamster Ovary Cells Via CRISPR/Cas9 and Fluorescent Enrichment

    DEFF Research Database (Denmark)

    Lee, Jae Seong; Grav, Lise Marie; Pedersen, Lasse Ebdrup

    2016-01-01

    Targeted gene integration into site-specific loci can be achieved in Chinese hamster ovary (CHO) cells via CRISPR/Cas9 genome editing technology and the homology-directed repair (HDR) pathway. The low efficiency of HDR often requires antibiotic selection, which limits targeted integration...

  6. Uranium enrichment

    International Nuclear Information System (INIS)

    1991-11-01

    This paper analyzes under four different scenarios the adequacy of a $500 million annual deposit into a fund to pay for the cost of cleaning up the Department of Energy's (DOE) three aging uranium enrichment plants. These plants are located in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. In summary the following was found: A fixed annual $500 million deposit made into a cleanup fund would not be adequate to cover total expected cleanup costs, nor would it be adequate to cover expected decontamination and decommissioning (D and D) costs. A $500 million annual deposit indexed to an inflation rate would likely be adequate to pay for all expected cleanup costs, including D and D costs, remedial action, and depleted uranium costs

  7. Comparison of low enriched uranium (UAl{sub x}-Al and U-Ni) targets with different geometries for the production of molybdenum-99 in the RMB (Brazilian multipurpose reactor)

    Energy Technology Data Exchange (ETDEWEB)

    Domingos, Douglas B.; Silva, Antonio T. e; Joao, Thiago G.; Silva, Jose Eduardo R. da; Angelo, Gabriel; Fedorenko, Giuliana G., E-mail: teixeira@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Nishiyama, Pedro J.B. de O., E-mail: pedro.julio@ctmsp.mar.mil.b [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), Sao Paulo, SP (Brazil)

    2011-07-01

    The Brazilian Multipurpose Reactor (RMB), now in the conception design phase, is being designed in Brazil to attend the demand of radiopharmaceuticals in the country and conduct researches in various areas. The new reactor, planned for 30 MW, will replace the IEA-R1 reactor of IPEN-CNEN/SP. Low enriched uranium (<20% {sup 235}U) UAl{sub x} dispersed in Al (plate geometry) and metallic uranium foil targets (plate and cylinder geometries) are being considered for production of Molybdenum-99 ({sup 99}Mo) by fission. Neutronic and thermal-hydraulics calculations were performed to compare the production of {sup 99}Mo for these targets in the RMB. For the neutronic calculations were utilized the computer codes Hammer-Technion, Citation and Scale and for the thermal-hydraulics calculations were utilized the computer code MTRCR-IEAR1 and ANSYS CFX. (author)

  8. Production of 14 MeV neutrons from D-D neutron generators

    International Nuclear Information System (INIS)

    Cecil, F.E.; Nieschmidt, E.B.

    1986-01-01

    The production of 14 MeV neutrons from a D-D neutron generator resulting from tritium buildup from the d(d,p)t reaction in the target is discussed. The effect of the 14 MeV neutrons on fast neutron activation analysis with D-D neutron generators is evaluated. (orig.)

  9. Boron isotopic enrichment by displacement chromatography

    International Nuclear Information System (INIS)

    Mohapatra, K.K.; Bose, Arun

    2014-01-01

    10 B enriched boron is used in applications requiring high volumetric neutron absorption (absorption cross section- 3837 barn for thermal and 1 barn for 1 MeV fast neutron). It is used in fast breeder reactor (as control rod material), in neutron counter, in Boron Neutron Capture Therapy etc. Owing to very small separation factor, boron isotopic enrichment is a complex process requiring large number of separation stages. Heavy Water Board has ventured in industrial scale production of 10 B enriched boron using Exchange Distillation Process as well as Ion Displacement Chromatography Process. Ion Displacement Chromatography process is used in Boron Enrichment Plant at HWP, Manuguru. It is based on isotopic exchange between borate ions (B(OH) 4 - ) on anion exchange resin and boric acid passing through resin. The isotopic exchange takes place due to difference in zero point energy of 10 B and 11 B

  10. Multiplicity of secondary electrons emitted by carbon thin targets by impact of H{sup 0}, H{sub 2}{sup +} and H{sub 3}{sup +} projectiles at MeV energies; Multiplicite des electrons secondaires emis par des cibles minces de carbone sous l`impact de projectiles H{sup 0}, H{sub 2}{sup +} et H{sub 3}{sup +} d`energie de l`ordre du MeV

    Energy Technology Data Exchange (ETDEWEB)

    Vidovic, Zvonimir [Inst. de Physique Nucleaire, Lyon-1 Univ., 69 - Villeurbanne (France)

    1997-06-24

    This work focuses on the study of the emission statistics of secondary electrons from thin carbon foils bombarded with H{sup 0}, H{sub 2}{sup +} and H{sub 3}{sup +} projectiles in the 0.25 - 2.2 MeV energy range. The phenomenon of secondary electron emission from solids under the impact of swift ions is mainly due to inelastic interactions with target electrons. Phenomenological and theoretical descriptions as well as a summary of the main theoretical models are the subjects of the first chapter. The experimental set-up used to measure event by event the electron emission of the two faces of the thin carbon foils crossed by an energetic projectile is described in the chapter two. In this chapter there are also presented the method and the algorithms used to process experimental spectra in order to obtain the statistical distribution of the emitted electrons. Chapter three presents the measurements of secondary electron emission induced by H{sup 0} atoms passing through thin carbon foils. The secondary electron yields are studied in correlation with emergent projectile charge state. We show the peculiar role of the projectile electron, whether it remains or not bound to the incident proton. The fourth chapter is dedicated to the secondary electron emission induced by H{sub 2}{sup +} and H{sub 3}{sup +} polyatomic ions. The results are interpreted in terms of collective effects in the interactions of the ions with solids. The role of the proximity of the protons, molecular ions fragments, upon the amplitude of these collected effects is evidenced from the study of the statistics of forward emission. The experiments allowed us to shed light on various aspects of atom and polyatomic ion interactions with solid surfaces. (author) 136 refs., 41 figs., 3 tabs.

  11. Neutron-induced fission cross sections of uraniums up to 40 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Maslov, V.M. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus); Hasegawa, A.

    1998-11-01

    Statistical theory of nuclear reactions, well-proved below 20 MeV, is applied for {sup 235}U and {sup 238}U fission data analysis up to {approx}40 MeV. It is shown that measured data could be reproduced. Chance structure of measured fission cross section is provided, it`s validity is supported by description of data for competing (n,xn)-reactions. Role of fissility of target nucleus is addressed. It seems that gap in incident neutron energy interval of 20 MeV - 50 MeV, below which evaluation approaches are well-developed, and above which simplified statistical approaches are valid, could be covered. (author)

  12. The 200 MeV cyclotron facility

    International Nuclear Information System (INIS)

    1987-01-01

    Beams of protons with several different energies have now been successfully transported between the injector cyclotron SPC1 and the SSC. Some small modifications to the placement of steering magnets and diagnostic equipment have been made in the light of our operational experience, which should improve the ease of tuning this beamline. Proton beams up to 200 MeV in energy have been transported to the experimental areas, where experiments in nuclear physics have been successful conducted. Three of the experimental beamlines are now in operation. Beams of 66 MeV protons have also been transported to targets in the isotope production vault, without difficulty. Field mapping of the remaining quadrupoles on site has been completed. Installation of and alignment of magnets up to the beam swinger is also complete, although the beam tube itself, plus vacuum and diagnostic equipment must still be tackled. The beam swinger has been designed and detailed in the drawing office, and is now being manufactured locally. The beamline elements for the sepctrometer beamline remain to be purchased. A personal computer has been purchased for controlling the field-mapping equipment for the spectrometer magnets, which are being manufactured in this country. A number of computer programs have been written for conversion of calibrated quadrupole and dipole magnet field data to absolute current values for the control system. Other programs permit diagnostic measurements of beam profiles to be used to calculated the beam emittance, or to set steering magnets so that the beam is correctly aligned

  13. HIGH ENERGY RADIOGRAPHY-1-30 Mev

    Energy Technology Data Exchange (ETDEWEB)

    Bly, James H.

    1963-10-15

    From 1963 American Society of Metals/Materials Show, Cleveland, Oct. 1963. A survey of the field of radiographic inspection of thick sections, at one million volts energy or more, shows that this field has become a major branch of radiographic testing. More than a dozen models of x-ray generators are now commercially available in this field, over the range from 1 to 31 Mev, with outputs up to more than two orders of magnitude greater than can be obtained from radiographic isotope sources, and with smaller spot size. A study of the radiographic characteristics of x rays in this region shows that energies available cover the range of minimum absorption and scattering for most materials and approach this range for solid propellant; at higher energies severe coverage restrictions are imposed; output powers on small spots are near the limits of present target technology. It would appear that some degree of technological maturity'' has been achieved. Radiographic technique at 1 to 30 Mev is straightforward, following the same basic principles as in conventional radiography. Specialized aspects of technique are individually discussed. The wellknown 1 and 2 million volt equlpments are supplemented by a wide variety of higher-energy machines, with energy and output ratings to satisfy almost any radiographic need. Some examples are epitomized, and a brief discussion of possible future developments is presented. (auth)

  14. Production of sup 5 sup 5 Co via the sup 5 sup 4 Fe(d, n)-process and excitation functions of sup 5 sup 4 Fe(d, t) sup 5 sup 3 Fe and sup 5 sup 4 Fe(d, alpha) sup 5 sup 2 sup m Mn reactions from threshold up to 13.8 MeV

    CERN Document Server

    Zaman, M R; Qaim, S M

    2003-01-01

    For production of the medically interesting beta; sup + -emitter sup 5 sup 5 Co (T sup 1 sup / sup 2 = 17.6 h) via the sup 5 sup 4 Fe(d, n)-reaction, 91.6% enriched sup 5 sup 4 Fe sub 2 O sub 3 , mixed with Al powder, was pressed to a pellet which could be irradiated with 14 MeV deuterons at 4 mu A in a water-cooled target system. A separation method was developed which led to > 99.9% pure sup 5 sup 5 Co and allowed a recovery of the enriched target material. For a target thickness of E sub d = 12.6 -> 5 MeV, the experimental thick target yield of sup 5 sup 5 Co after chemical separation amounted to about 13 MBq/mu A.h, which is about 60% of the theoretical value. In a 3 h irradiation at 4 mu A, the batch yield of sup 5 sup 5 Co achieved was 160 MBq (4.3 mCi). An 8 h irradiation could lead to a batch yield of about 400 MBq. The sup 5 sup 4 Fe(d, n) reaction leads to the highest purity sup 5 sup 5 Co but it is essential that the isotopic enrichment of the target is not less than 90%. In addition to the product...

  15. Strategy for Extracting DNA from Clay Soil and Detecting a Specific Target Sequence via Selective Enrichment and Real-Time (Quantitative) PCR Amplification ▿

    Science.gov (United States)

    Yankson, Kweku K.; Steck, Todd R.

    2009-01-01

    We present a simple strategy for isolating and accurately enumerating target DNA from high-clay-content soils: desorption with buffers, an optional magnetic capture hybridization step, and quantitation via real-time PCR. With the developed technique, μg quantities of DNA were extracted from mg samples of pure kaolinite and a field clay soil. PMID:19633108

  16. Recoil proton polarization of neutral pion photoproduction from proton in the energy range between 400 MeV and 1142 MeV

    International Nuclear Information System (INIS)

    Kato, S.; Miyachi, T.; Sugano, K.; Toshioka, K.; Ukai, K.

    1979-08-01

    The recoil proton polarization of the reaction γp → π 0 p were measured at a C.M. angle of 100 0 for incident photon energies between 451 and 1106 MeV, and at an angle of 130 0 for energies from 400 MeV to 1142 MeV. One photon decayed from a π 0 -meson and a recoil proton were detected in coincidence. Two kinds of polarization scatterers were employed. In the range of proton kinetic energy less than 420 MeV and higher than 346 MeV, carbon plates and liquid hydrogen were used for determining the polarization. Results are compared with recent phenomenological analyses. From the Comparison between the present data and the asymmetry data given by the polarized target, the contribution of the invariant amplitudes A 3 can be estimated to be small at 100 0 . (author)

  17. Targeted enrichment of ancient pathogens yielding the pPCP1 plasmid of Yersinia pestis from victims of the Black Death.

    Science.gov (United States)

    Schuenemann, Verena J; Bos, Kirsten; DeWitte, Sharon; Schmedes, Sarah; Jamieson, Joslyn; Mittnik, Alissa; Forrest, Stephen; Coombes, Brian K; Wood, James W; Earn, David J D; White, William; Krause, Johannes; Poinar, Hendrik N

    2011-09-20

    Although investigations of medieval plague victims have identified Yersinia pestis as the putative etiologic agent of the pandemic, methodological limitations have prevented large-scale genomic investigations to evaluate changes in the pathogen's virulence over time. We screened over 100 skeletal remains from Black Death victims of the East Smithfield mass burial site (1348-1350, London, England). Recent methods of DNA enrichment coupled with high-throughput DNA sequencing subsequently permitted reconstruction of ten full human mitochondrial genomes (16 kb each) and the full pPCP1 (9.6 kb) virulence-associated plasmid at high coverage. Comparisons of molecular damage profiles between endogenous human and Y. pestis DNA confirmed its authenticity as an ancient pathogen, thus representing the longest contiguous genomic sequence for an ancient pathogen to date. Comparison of our reconstructed plasmid against modern Y. pestis shows identity with several isolates matching the Medievalis biovar; however, our chromosomal sequences indicate the victims were infected with a Y. pestis variant that has not been previously reported. Our data reveal that the Black Death in medieval Europe was caused by a variant of Y. pestis that may no longer exist, and genetic data carried on its pPCP1 plasmid were not responsible for the purported epidemiological differences between ancient and modern forms of Y. pestis infections.

  18. Investigations of nuclei-products formation in target and construction materials of electro-nuclear installations irradiated by 1.5 GeV and 130 MeV photons

    International Nuclear Information System (INIS)

    Titarenko, Y.E.; Karpihin, E.I.; Smolyakov, A.F.

    1996-01-01

    Different versions of installations for transmutation or incineration of actinides and long-lived fission products are being considered nowadays; the source of neutrons in these installations is supposed to be a nuclon-meson cascade arising under interaction of 0.8--1.5 GeV proton beam and the substance of a target. ''Heavy'' materials: eutectics of lead and bismuth or tangsten, are supposed to be used as targets. In correspondence with this, measurements of the cross sections of spallation of nuclides of these materials under impact of the protons of different energies are going on in ITEP. Nuclides used as construction materials for the accelerator are also being measured. Numerical simulation of experimental results with utilization of the codes HETC, INUCLE, CEM95 capable to calculate the process of nuclon- meson cascade in the investigated targets is being carried out

  19. High-resolution Auger spectroscopy on 79 MeV Ar5+, 89 MeV Ar6+, and 136 MeV Ar7+ ions after excitation by helium

    International Nuclear Information System (INIS)

    Schneider, T.

    1988-01-01

    In this thesis the atomic structure of highly excited Ar 6+ and Ar 7+ ions was studied. For this 79 MeV Ar 5+ , 89 MeV Ar 6+ , and 136 MeV Ar 7+ ions of a heavy ion accelerator were excited by a He gas target to autoionizing states and the Auger electrons emitted in the decay were measured in highly-resolving state. The spectra were taken under an observational angle of zero degree relative to the beam axis in order to minimize the kinematical broadening of the Auger lines. (orig./HSI) [de

  20. Mitoxantrone Loaded Superparamagnetic Nanoparticles for Drug Targeting: A Versatile and Sensitive Method for Quantification of Drug Enrichment in Rabbit Tissues Using HPLC-UV

    Directory of Open Access Journals (Sweden)

    Rainer Tietze

    2010-01-01

    Full Text Available In medicine, superparamagnetic nanoparticles bound to chemotherapeutics are currently investigated for their feasibility in local tumor therapy. After intraarterial application, these particles can be accumulated in the targeted area by an external magnetic field to increase the drug concentration in the region of interest (Magnetic-Drug-Targeting. We here present an analytical method (HPLC-UV, to detect pure or ferrofluid-bound mitoxantrone in a complex matrix even in trace amounts in order to perform biodistribution studies. Mitoxantrone could be extracted in high yields from different tissues. Recovery of mitoxantrone in liver tissue (5000 ng/g was 76±2%. The limit of quantification of mitoxantrone standard was 10 ng/mL ±12%. Validation criteria such as linearity, precision, and stability were evaluated in ranges achieving the FDA requirements. As shown for pilot samples, biodistribution studies can easily be performed after application of pure or ferrofluid-bound mitoxantrone.

  1. Theoretical estimation of "6"4Cu production with neutrons emitted during "1"8F production with a 30 MeV medical cyclotron

    International Nuclear Information System (INIS)

    Auditore, Lucrezia; Amato, Ernesto; Baldari, Sergio

    2017-01-01

    Purpose: This work presents the theoretical estimation of a combined production of "1"8F and "6"4Cu isotopes for PET applications. "6"4Cu production is induced in a secondary target by neutrons emitted during a routine "1"8F production with a 30 MeV cyclotron: protons are used to produce "1"8F by means of the "1"8O(p,n)"1"8F reaction on a ["1"8O]-H_2O target (primary target) and the emitted neutrons are used to produce "6"4Cu by means of the "6"4Zn(n,p)"6"4Cu reaction on enriched zinc target (secondary target). Methods: Monte Carlo simulations were carried out using Monte Carlo N Particle eXtended (MCNPX) code to evaluate flux and energy spectra of neutrons produced in the primary (Be+["1"8O]-H_2O) target by protons and the attenuation of neutron flux in the secondary target. "6"4Cu yield was estimated using an analytical approach based on both TENDL-2015 data library and experimental data selected from EXFOR database. Results: Theoretical evaluations indicate that about 3.8 MBq/μA of "6"4Cu can be obtained as a secondary, ‘side’ production with a 30 MeV cyclotron, for 2 h of irradiation of a proper designed zinc target. Irradiating for 2 h with a proton current of 120 μA, a yield of about 457 MBq is expected. Moreover, the most relevant contaminants result to be "6"3","6"5Zn, which can be chemically separated from "6"4Cu contrarily to what happens with proton irradiation of an enriched "6"4Ni target, which provides "6"4Cu mixed to other copper isotopes as contaminants. Conclusions: The theoretical study discussed in this paper evaluates the potential of the combined production of "1"8F and "6"4Cu for medical purposes, irradiating a properly designed target with 30 MeV protons. Interesting yields of "6"4Cu are obtainable and the estimation of contaminants in the irradiated zinc target is discussed. - Highlights: • "6"4Cu production with secondary neutrons from "1"8F production with protons was investigated. • Neutron reactions induced in enriched "6"4Zn

  2. Neutron Inelastic Scattering on 134Xe at En = 5 - 8 MeV

    Science.gov (United States)

    Kidd, Mary; Tornow, Werner; Finch, Sean; Krishichayan, Fnu; Bhike, Megha

    2017-09-01

    Neutrinoless double-beta decay (0 νββ) studies are both the best way to determine the Majorana nature of the neutrino and determine its effective mass. The two main experiments searching for 0 νββ -decay of 136Xe (Q value = 2457.8 keV) are Kamland-Zen and EXO-200. Though both experiments have enriched 136Xe targets, these targets still contain significant quantities of 134Xe. Recently, a new nuclear level was discovered in 134Xe that decays to the ground state emitting a 2485.7 keV gamma ray. The γ-ray production cross section for this branch was found to be on the order of 10 mb for incident neutron energies of 2.5-4.5 MeV. Here, we have extended the investigation of this level to higher incident neutron energies, and further explore the potential neutron-induced backgrounds on both 134Xe and 136Xe for extended neutron energies. We will report our preliminary results for neutron inelastic scattering on 134Xe in applications to 0 νββ decay searches. NSF PHY-1614348, DE-FG02-97ER41033.

  3. Juvenile psittacine environmental enrichment.

    Science.gov (United States)

    Simone-Freilicher, Elisabeth; Rupley, Agnes E

    2015-05-01

    Environmental enrichment is of great import to the emotional, intellectual, and physical development of the juvenile psittacine and their success in the human home environment. Five major types of enrichment include social, occupational, physical, sensory, and nutritional. Occupational enrichment includes exercise and psychological enrichment. Physical enrichment includes the cage and accessories and the external home environment. Sensory enrichment may be visual, auditory, tactile, olfactory, or taste oriented. Nutritional enrichment includes variations in appearance, type, and frequency of diet, and treats, novelty, and foraging. Two phases of the preadult period deserve special enrichment considerations: the development of autonomy and puberty. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Report of the Subcommittee on Domestic Uranium Enrichment

    International Nuclear Information System (INIS)

    1981-01-01

    A report by the Subcommittee on Domestic Uranium Enrichment to the Atomic Energy Commission is described; which covers the procedure of the domestic uranium enrichment by centrifugal process up to the commercial production, reviewing the current situation in this field. Domestic uranium enrichment is important in the aspects of securing stable enrichment service, establishing sound fuel cycle, and others. As the future target, the production around the year 2000 is set at 3,000 tons SWU per year at least. The business of uranium enrichment, which is now developed in the Power Reactor and Nuclear Fuel Development Corporation, is to be carried out by private enterprise. The contents are as follows: demand and supply balance of uranium enrichment service, significance of domestic uranium enrichment, evaluation of centrifugal uranium enrichment technology, the target of domestic uranium enrichment, the policy of domestic uranium enrichment promotion. (J.P.N.)

  5. Shielding calculations for industrial 5/7.5MeV electron accelerators using the MCNP Monte Carlo Code

    Science.gov (United States)

    Peri, Eyal; Orion, Itzhak

    2017-09-01

    High energy X-rays from accelerators are used to irradiate food ingredients to prevent growth and development of unwanted biological organisms in food, and by that extend the shelf life of the products. The production of X-rays is done by accelerating 5 MeV electrons and bombarding them into a heavy target (high Z). Since 2004, the FDA has approved using 7.5 MeV energy, providing higher production rates with lower treatments costs. In this study we calculated all the essential data needed for a straightforward concrete shielding design of typical food accelerator rooms. The following evaluation is done using the MCNP Monte Carlo code system: (1) Angular dependence (0-180°) of photon dose rate for 5 MeV and 7.5 MeV electron beams bombarding iron, aluminum, gold, tantalum, and tungsten targets. (2) Angular dependence (0-180°) spectral distribution simulations of bremsstrahlung for gold, tantalum, and tungsten bombarded by 5 MeV and 7.5 MeV electron beams. (3) Concrete attenuation calculations in several photon emission angles for the 5 MeV and 7.5 MeV electron beams bombarding a tantalum target. Based on the simulation, we calculated the expected increase in dose rate for facilities intending to increase the energy from 5 MeV to 7.5 MeV, and the concrete width needed to be added in order to keep the existing dose rate unchanged.

  6. Development of low enriched uranium target plates by thermo-mechanical processing of UAl2–Al matrix for production of 99Mo in Pakistan

    International Nuclear Information System (INIS)

    Ali, Kanwar Liaqat; Khan, Akhlaque Ahmad; Mushtaq, Ahmad; Imtiaz, Farhan; Ziai, Maratab Ali; Gulzar, Amir; Farooq, Muhammad; Hussain, Nazar; Ahmed, Nisar; Pervez, Shahid; Zaidi, Jamshed Hussain

    2013-01-01

    Uranium aluminide predominated with UAl 2 phase was prepared by arc-melting procedures and comminuted to required particle size. UAl 2 and Al powders were blended and compacted to achieve LEU fuel density of 2.17 g/cm 3 . The picture-frame technique was used to clad the dispersions (UAl 2 –Al) with aluminum. A few target plates were fabricated by thermo-mechanical processing (hot rolling and annealing) of UAl 2 –Al matrix contained in roll billet of Al. The fabricated plates were characterized by destructive and some of non-destructive testing techniques and then annealed to achieve required phase of uranium aluminide for proper dissolution in basic media

  7. Other enrichment related contracts

    International Nuclear Information System (INIS)

    Hall, J.C.

    1978-01-01

    In addition to long-term enrichment contracts, DOE has other types of contracts: (1) short-term, fixed-commitment enrichment contract; (2) emergency sales agreement for enriched uranium; (3) feed material lease agreement; (4) enriched uranium storage agreement; and (5) feed material usage agreement

  8. (n, Xn) cross sections measurements at 96 MeV

    International Nuclear Information System (INIS)

    Sagrado Garcia, Inmaculada C.

    2006-01-01

    Nucleon induced reactions in the 20-200 MeV energy range are intensively studied since a long time. The evaporation and the pre-equilibrium processes correspond to an important contribution of the production cross section in these reactions. Several theoretical approaches have been proposed and their predictions must be tested. The experimental results shown in this work are the only complete set of data for the (n, Xn) reactions in this energy range. Neutron double differential cross sections measurements using lead and iron targets for an incident neutron beam at 96 MeV were carried out at TSL laboratory, in Uppsala (Sweden). The measurements have been performed for the first time with an energy threshold of 2 MeV and for a wide angular range (15 deg.-98 deg.). Neutrons have been detected using two independent setups, DECOI and DEMON and CLODIA and SCANDAL, in order to cover the whole energy range (2-100 MeV). The angular distributions, the differential cross sections and the total inelastic production cross sections have been calculated using the double differential cross sections. The comparisons between the experimental data and the predictions given by two of the most popular simulation codes, GEANT3 and MCNPX, have been performed, as well as the comparison with the predictions of the microscopic simulation model DYWAN, selected for its original treatment of nucleon-nucleus reactions. (author) [fr

  9. Motif enrichment tool.

    Science.gov (United States)

    Blatti, Charles; Sinha, Saurabh

    2014-07-01

    The Motif Enrichment Tool (MET) provides an online interface that enables users to find major transcriptional regulators of their gene sets of interest. MET searches the appropriate regulatory region around each gene and identifies which transcription factor DNA-binding specificities (motifs) are statistically overrepresented. Motif enrichment analysis is currently available for many metazoan species including human, mouse, fruit fly, planaria and flowering plants. MET also leverages high-throughput experimental data such as ChIP-seq and DNase-seq from ENCODE and ModENCODE to identify the regulatory targets of a transcription factor with greater precision. The results from MET are produced in real time and are linked to a genome browser for easy follow-up analysis. Use of the web tool is free and open to all, and there is no login requirement. ADDRESS: http://veda.cs.uiuc.edu/MET/. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  10. Photospallation reactions of 133Cs and 139La by 100 MeV- and 200 MeV bremsstrahlungs

    International Nuclear Information System (INIS)

    Sakamoto, K.; Toramoto, H.; Hamajima, Y.; Okada, K.; Dohniwa, M.

    1984-01-01

    Spallation yields relative to the 196 Au yield from 197 Au(γ,n) of 26 to 46 nuclides of Sb, Te, I, Xe, Cs and/or Ba and La from 133 Cs and 139 La targets irradiated with bremsstrahlungs of end energies of 100 MeV and 200 MeV were radiochemically determined. The isomeric yield ratios for 132 La and 131 Ba from the ( 139 La + 100 MeV-γ), 132 La, 131 Ba, 121 Te and 119 Te from the ( 139 La + 200 MeV-γ, and 120 I, 121 Te and 119 Te from the ( 133 Cs +- 200 MeV-γ) were also determined. The isotopic yields from the (γ,yn) reactions decrease exponentially with increase of y up to 5, and show no dependence on energy and targets studied, indicating that the reactions of a few neutron emissions occur at energies lower than 100 MeV. When the product yields from the (γ,xpyn) reactions were plotted against (x + y) for each x (isotopic distribution), a regular variation of the Gaussian distributions, typical of nuclear spallation, was observed. Isobaric mass distributions and charge dispersions were deduced to extract characteristic features of these reactions. The isobaric distributions due only to photons of 100 MeV to 200 MeV, which were obtained by subtracting the 100 MeV-yields from the 200 MeV-yields, are very close to a symmetric one peaking at about 8 amu from the target masses. Nuclear charges are also dispersed symmetrically, with most probable N/Zsub(p) of about 1.3 replaced by about 1 amu to the neutron-deficient side from the beta stability valley in all the cases studied. Parameters included in Rudstam's semi-empirical formula were examined by comparing with the observed yield curves. The P values of 0.45 and 0.65, chosen for a better fit to the 200 MeV data on 133 Cs and 139 La, respectively, were larger than the predictions reported in the literature. The magic number effects of 139 La may explain the target-differences in mass distributions. (orig.)

  11. Zone plate imaging of 14-MeV neutrons

    International Nuclear Information System (INIS)

    Lerche, R.A.; Lane, S.M.; Hawryluk, A.M.; Ceglio, N.M.

    1986-01-01

    At Livermore we are interested in imaging the thermonuclear burn region of fusion targets irradiated at our Nova laser facility. We expect compressed core diameters to be 10's of microns, and would like images with better than 10-μm resolution. Alpha particle images provided the first direct information about the thermonuclear burn geometry in thin walled exploding pusher targets. In future high density target experiments, only highly penetrating radiations like the 14-MeV neutrons will escape the target core to provide information about the burn region. To make the measurement with a neutron ''pinhole'' camera requires a 10μm pinhole through about 10 cm of material and 10 14 to 10 15 source neutrons. Penumbral imaging offers some improvement over a pinhole. Zone plate coded imaging (ZPCI) techniques are particularly well suited for imaging small objects like the compressed core of a laser fusion target. We have been using ZPCI techniques to image nonpenetrating radiations like x rays and alpha particles for about 10 years. The techniques are well developed. Imaging penetrating radiations like 14-MeV neutrons using ZPCI techniques has several possible advantages. The large solid angle subtended by the Zone plate might substantially reduce the required target neutron yield needed to produce a useful image, and a neutron zone plate system with 10-μm resolution might be easier to fabricate and characterize than a pinhole system. This paper explores the use of ZPCI techniques with penetrating radiation

  12. Stable isotope enrichment: Current and future potential

    International Nuclear Information System (INIS)

    Tracy, J.G.; Aaron, W.S.

    1992-01-01

    Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities

  13. Stable isotope enrichment - current and future potential

    International Nuclear Information System (INIS)

    Tracy, J.G.; Aaron, W.S.

    1993-01-01

    Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL. This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities. (orig.)

  14. Neutron scattering differential cross sections of carbon and bismuth at 37 MeV

    International Nuclear Information System (INIS)

    Zhou Zuying; Tang Hongqing; Qi Bujia; Zhou Chenwei; Du Yanfeng; Xia Haihong; Walter, R.L.; Tornow, W.; Howell, C.; Braun, R.; Roper, C.; Chen Zemin; Chen Zhengpeng; Chen Yingtang

    1997-01-01

    Elastic differential cross sections of 37 MeV neutrons scattered from carbon and bismuth were measured in the angular range 11 to 160 degrees by means of the multi-detector TOF facility. The 37 MeV neutrons were produced via the T(d,n) 4 He reaction in a tritium gas target. The pulsed 20 MeV deuteron beam was provided by the HI-13 tandem accelerator. The angular distribution of scattered neutrons from carbon and bismuth were measured in the angular range 11 degree to 145 degree and 11 degree to 160 degree respectively in steps of about 3 degree

  15. Routine production of copper-64 using 11.7MeV protons

    Energy Technology Data Exchange (ETDEWEB)

    Jeffery, C. M.; Smith, S. V.; Asad, A. H.; Chan, S.; Price, R. I. [Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, 6009 (Australia); Centre for Forensic Science, University of Western Australia, Nedlands, Western Australia, 6009 (Australia) and ARC Centre of Excellence in A (Australia); ARC Centre of Excellence in Antimatter-Matter Studies, Australian National University, Canberra, ACT 0200 (Australia) and Collider-Accelerator Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, 6009 (Australia); ARC Centre of Excellence in Antimatter-Matter Studies, Australian National University, Canberra, ACT 0200 (Australia) and Imaging and Applied (Australia); Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, 6009 (Australia); Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, 6009 (Australia) and School of Physics, University of Western Australia, Nedlands, Western Australia, 6009 (Australia)

    2012-12-19

    Reliable production of copper-64 ({sup 64}Cu) was achieved by irradiating enriched nickel-64 ({sup 64}Ni, >94.8%) in an IBA 18/9 cyclotron. Nickel-64 (19.1 {+-} 3.0 mg) was electroplated onto an Au disc (125{mu}m Multiplication-Sign 15mm). Targets were irradiated with 11.7 MeV protons for 2 hours at 40{mu}A. Copper isotopes ({sup 60,61,62,64}Cu) were separated from target nickel and cobalt isotopes ({sup 55,57,61}Co) using a single ion exchange column, eluted with varying concentration of low HCl alcohol solutions. The {sup 64}Ni target material was recovered and reused. The {sup 64}Cu production rate was 1.46{+-}0.3MBq/{mu}A.hr/mg{sup 64}Ni(n = 10) (with a maximum of 2.6GBq of {sup 64}Cu isolated after 2hr irradiation at 40uA. Radionuclidic purity of the {sup 64}Cu was 98.7 {+-} 1.6 % at end of separation. Cu content was < 6mg/L (n = 21). The specific activity of {sup 64}Cu was determined by ICP-MS and by titration with Diamsar to be 28.9{+-}13.0GBq/{mu}mol[0.70{+-}0.35Ci/{mu}mol]/({mu}A.hr/mg{sup 64}Ni)(n = 10) and 13.1{+-}12.0GBq/{mu}mol[0.35{+-}0.32Ci/{mu}mol]/({mu}A.hr/mg{sup 64}Ni)(n 9), respectively; which are in agreement, however, further work is required.

  16. Tritium production in thorium by 135 MeV protons

    International Nuclear Information System (INIS)

    Lefort, M.; Simonoff, G.; Tarrago, X.; Bibron, R.

    1960-01-01

    We have measured the cross-section of tritium production by bombardment of thorium by 135 MeV protons in the Orsay synchro-cyclotron. The tritium was separated from the targets by heating in a graphite crucible with a high-frequency generator, under hydrogen gas pressure. Tritiated water was synthesised and the tritium was measured with liquid scintillator. A value of 19.5 ± 0.05 mbarns was obtained for the tritium-cross section and ten percent of tritons have energies higher than 35 MeV. This large cross-section is attributed to a double pick-up process. Reprint of a paper published in Le Journal de Physique et le Radium, t. 20, p. 959, dec 1959 [fr

  17. Derived enriched uranium market

    International Nuclear Information System (INIS)

    Rutkowski, E.

    1996-01-01

    The potential impact on the uranium market of highly enriched uranium from nuclear weapons dismantling in the Russian Federation and the USA is analyzed. Uranium supply, conversion, and enrichment factors are outlined for each country; inventories are also listed. The enrichment component and conversion components are expected to cause little disruption to uranium markets. The uranium component of Russian derived enriched uranium hexafluoride is unresolved; US legislation places constraints on its introduction into the US market

  18. Uranium enrichment plans

    International Nuclear Information System (INIS)

    Thomas, D.C.; Gagne, R.W.

    1978-01-01

    The following topics are covered: the status of the Government's existing uranium enrichment services contracts, natural uranium requirements based on the latest contract information, uncertainty in predicting natural uranium requirements based on uranium enrichment contracts, and domestic and foreign demand assumed in enrichment planning

  19. Photoresponse of {sup 94}Mo at energies up to 8.6 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Romig, Christopher; Fritzsche, M.; Lindenberg, K.; Pietralla, N.; Savran, D.; Sonnabend, K. [Institut fuer Kernphysik, Technische Universitaet, Darmstadt (Germany); Rusev, G.; Tonchev, A.P.; Tornow, W.; Weller, H.R. [Triangle Universities Nuclear Laboratory, Duke University, Durham, NC (United States); Zilges, A. [Institut fuer Kernphysik, Universitaet Koeln (Germany)

    2009-07-01

    The isotope {sup 94}Mo was investigated in nuclear resonance fluorescence experiments at the High Intensity Photon Setup (HIPS) at the S-DALINAC in Darmstadt using bremsstrahlung photons with energies of 7.65 and 8.6 MeV, respectively, and at the High Intensity {gamma}-ray Source (HI{gamma}S) at Duke University using photons from Laser Compton backscattering. Thereby over 60 excitations were found which could be assigned to {sup 94}Mo due to the highly enriched sample. In the energy region between 5.4 and 8 MeV many transitions could be classified as dipole transitions and cross sections, angular momentum quantum numbers, half-lifes and transition strengths were determined. At HI{gamma}S the parity quantum numbers of 40 excitations between 5.5 and 7.0 MeV could be determined. The methods and results are presented.

  20. Neutron interrogation of actinides with a 17 MeV electron accelerator and first results from photon and neutron interrogation non-simultaneous measurements combination

    Energy Technology Data Exchange (ETDEWEB)

    Sari, A., E-mail: adrien.sari@cea.fr [CEA, LIST, Laboratoire Capteurs et Architectures Electroniques, 91191 Gif-sur-Yvette Cedex (France); Carrel, F.; Lainé, F. [CEA, LIST, Laboratoire Capteurs et Architectures Electroniques, 91191 Gif-sur-Yvette Cedex (France); Lyoussi, A. [CEA, DEN, 13108 Saint-Paul-Lez-Durance Cedex (France)

    2013-10-01

    In this article, we demonstrate the feasibility of neutron interrogation using the conversion target of a 17 MeV linear electron accelerator as a neutron generator. Signals from prompt neutrons, delayed neutrons, and delayed gamma-rays, emitted by both uranium and plutonium samples were analyzed. First results from photon and neutron interrogation non-simultaneous measurements combination are also reported in this paper. Feasibility of this technique is shown in the frame of the measurement of uranium enrichment. The latter was carried out by combining detection of prompt neutrons from thermal fission and delayed neutrons from photofission, and by combining delayed gamma-rays from thermal fission and delayed gamma-rays from photofission.

  1. Scale-up of high specific activity {sup 186g}Re production using graphite-encased thick {sup 186}W targets and demonstration of an efficient target recycling process

    Energy Technology Data Exchange (ETDEWEB)

    Balkin, Ethan R.; Gagnon, Katherine; Dorman, Eric [Washington Univ., Seattle, WA (United States). Dept. of Radiation Oncology; and others

    2017-07-01

    Production of high specific activity {sup 186g}Re is of interest for development of theranostic radiopharmaceuticals. Previous studies have shown that high specific activity {sup 186g}Re can be obtained by cyclotron irradiation of enriched {sup 186}W via the {sup 186}W(d,2n){sup 186g}Re reaction, but most irradiations were conducted at low beam currents and for short durations. In this investigation, enriched {sup 186}W metal targets were irradiated at high incident deuteron beam currents to demonstrate production rates and contaminants produced when using thick targets. Full-stopping thick targets, as determined using SRIM, were prepared by uniaxial pressing of powdered natural abundance W metal or 96.86% enriched {sup 186}W metal encased between two layers of graphite flakes for target material stabilization. An assessment of structural integrity was made on each target preparation. To assess the performance of graphite-encased thick {sup 186}W metal targets, along with the impact of encasing on the separation chemistry, targets were first irradiated using a 22 MeV deuteron beam for 10 min at 10, 20, and 27 μA, with an estimated nominal deuteron energy of 18.7 MeV on the {sup 186}W target material (after energy degradation correction from top graphite layer). Gamma-ray spectrometry was performed post EOB on all targets to assess production yields and radionuclidic byproducts. The investigation also evaluated a method to recover and recycle enriched target material from a column isolation procedure. Material composition analyses of target materials, pass-through/wash solutions and recycling process isolates were conducted with SEM, FTIR, XRD, EDS and ICP-MS spectrometry. To demonstrate scaled-up production, a graphite-encased {sup 186}W target made from recycled {sup 186}W was irradiated for ∝2 h with 18.7 MeV deuterons at a beam current of 27 μA to provide 0.90 GBq (24.3 mCi) of {sup 186g}Re, decay-corrected to the end of bombardment. ICP-MS analysis of the

  2. Uranium Enrichment, an overview

    International Nuclear Information System (INIS)

    Coates, J.H.

    1994-01-01

    This general presentation on uranium enrichment will be followed by lectures on more specific topics including descriptions of enrichment processes and assessments of the prevailing commercial and industrial situations. I shall therefore avoid as much as possible duplications with these other lectures, and rather dwell on: some theoretical aspects of enrichment in general, underlying the differences between statistical and selective processes, a review and comparison between enrichment processes, remarks of general order regarding applications, the proliferation potential of enrichment. It is noteworthy that enrichment: may occur twice in the LWR fuel cycle: first by enriching natural uranium, second by reenriching uranium recovered from reprocessing, must meet LWR requirements, and in particular higher assays required by high burn up fuel elements, bears on the structure of the entire front part of the fuel cycle, namely in the conversion/reconversion steps only involving UF 6 for the moment. (author). tabs., figs., 4 refs

  3. Extension of activation cross-section data of deuteron induced nuclear reactions on cadmium up to 50 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Hermanne, A., E-mail: aherman@vub.ac.be [Cyclotron Laboratory, Vrije Universiteit Brussel, Brussels (Belgium); Tárkányi, F.; Takács, S.; Ditrói, F. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary)

    2016-10-15

    The excitation functions for {sup 109,110g,111m+g,113m,114m,115m}In, {sup 107,109,115m,115g}Cd and {sup 105g,106m,110g,111}Ag are presented for stacked foil irradiations on {sup nat}Cd targets in the 49–33 MeV deuteron energy domain. Reduced uncertainty is obtained by determining incident particle flux and energy scale relative to re-measured monitor reactions {sup nat}Al(d,x){sup 22,24}Na. The results were compared to our earlier studies on {sup nat}Cd and on enriched {sup 112}Cd targets. The merit of the values predicted by the TALYS 1.6 code (resulting from a weighted combination of reaction cross-section data on all stable Cd isotopes as available in the on-line libraries TENDL-2014 and TENDL-2015) is discussed. Influence on optimal production routes for several radionuclides with practical applications ({sup 111}In, {sup 114m}In, {sup 115}Cd, {sup 109,107}Cd….) is reviewed.

  4. Advanced enrichment techniques

    International Nuclear Information System (INIS)

    Johnson, A.

    1988-01-01

    BNFL is in a unique position in that it has commercial experience of diffusion enrichment, and of centrifuge enrichment through its associate company Urenco. In addition BNFL is developing laser enrichment techniques as part of a UK development programme in this area. The paper describes the development programme which led to the introduction of competitive centrifuge enrichment technology by Urenco and discusses the areas where improvements have and will continue to be made in the centrifuge process. It also describes the laser development programme currently being undertaken in the UK. The paper concludes by discussing the relative merits of the various methods of uranium enrichment, with particular reference to the enrichment market likely to obtain over the rest of the century

  5. Advanced enrichment techniques

    International Nuclear Information System (INIS)

    Johnson, A.

    1987-01-01

    BNFL is in a unique position in that it has commercial experience of diffusion enrichment, and of centrifuge enrichment through its associate company Urenco. In addition BNFL is developing laser enrichment techniques as part of a UK development programme in this area. The paper describes the development programme which led to the introduction of competitive centrifuge enrichment technology by Urenco and discusses the areas where improvements have and will continue to be made in the centrifuge process. It also describes the laser development programme currently being undertaken in the UK. The paper concludes by discussing the relative merits of the various methods of uranium enrichment, with particular reference to the enrichment market likely to obtain over the rest of the century. (author)

  6. Shielding measurements for a 230 MeV proton beam

    International Nuclear Information System (INIS)

    Siebers, J.V.

    1990-01-01

    Energetic secondary neutrons produced as protons interact with accelerator components and patients dominate the radiation shielding environment for proton radiotherapy facilities. Due to the scarcity of data describing neutron production, attenuation, absorbed dose, and dose equivalent values, these parameters were measured for 230 MeV proton bombardment of stopping length Al, Fe, and Pb targets at emission angles of 0 degree, 22 degree, 45 degree, and 90 degree in a thick concrete shield. Low pressure tissue-equivalent proportional counters with volumes ranging from 1 cm 3 to 1000 cm 3 were used to obtain microdosimetric spectra from which absorbed dose and radiation quality are deduced. Does equivalent values and attenuation lengths determined at depth in the shield were found to vary sharply with angle, but were found to be independent of target material. Neutron dose and radiation length values are compared with Monte Carlo neutron transport calculations performed using the Los Alamos High Energy Transport Code (LAHET). Calculations used 230 MeV protons incident upon an Fe target in a shielding geometry similar to that used in the experiment. LAHET calculations overestimated measured attenuation values at 0 degree, 22 degree, and 45 degree, yet correctly predicted the attenuation length at 90 degree. Comparison of the mean radiation quality estimated with the Monte Carlo calculations with measurements suggest that neutron quality factors should be increased by a factor of 1.4. These results are useful for the shielding design of new facilities as well as for testing neutron production and transport calculations

  7. Inoculation stress hypothesis of environmental enrichment.

    Science.gov (United States)

    Crofton, Elizabeth J; Zhang, Yafang; Green, Thomas A

    2015-02-01

    One hallmark of psychiatric conditions is the vast continuum of individual differences in susceptibility vs. resilience resulting from the interaction of genetic and environmental factors. The environmental enrichment paradigm is an animal model that is useful for studying a range of psychiatric conditions, including protective phenotypes in addiction and depression models. The major question is how environmental enrichment, a non-drug and non-surgical manipulation, can produce such robust individual differences in such a wide range of behaviors. This paper draws from a variety of published sources to outline a coherent hypothesis of inoculation stress as a factor producing the protective enrichment phenotypes. The basic tenet suggests that chronic mild stress from living in a complex environment and interacting non-aggressively with conspecifics can inoculate enriched rats against subsequent stressors and/or drugs of abuse. This paper reviews the enrichment phenotypes, mulls the fundamental nature of environmental enrichment vs. isolation, discusses the most appropriate control for environmental enrichment, and challenges the idea that cortisol/corticosterone equals stress. The intent of the inoculation stress hypothesis of environmental enrichment is to provide a scaffold with which to build testable hypotheses for the elucidation of the molecular mechanisms underlying these protective phenotypes and thus provide new therapeutic targets to treat psychiatric/neurological conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Uranium enrichment: an overview

    International Nuclear Information System (INIS)

    Cazalet, J.

    1995-01-01

    This paper is a general presentation of uranium enrichment processes and assessments of the prevailing commercial and industrial situations. It gives first some theoretical aspects of enrichment in general and explains the differences between statistical and selective processes in particular. Then a review of the different processes is made with a comparison between them. Finally, some general remarks concerning applications are given and the risks of proliferation related to enrichment are mentioned. (J.S.). 4 refs., 5 figs., 8 tabs

  9. The enrichment secondary market

    International Nuclear Information System (INIS)

    Einbund, D.R.

    1986-01-01

    This paper will addresses two topics: the background to the present status of the enrichment secondary market and the future outlook of the secondary market in enrichment services, and the viability of the nuclear fuel brokerage industry. These two topics are inevitably connected, as most secondary market activity, not only in enrichment but also in natural uranium, has traditionally been conducted with the participation of brokers. Therefore, the author interrelates these topics

  10. Excitation functions of deuteron induced nuclear reactions on natMo up to 21 MeV. An alternative route for the production of 99mTc and 99Mo

    International Nuclear Information System (INIS)

    Sonck, M.; Hermanne, A.; Takacs, S.; Szelecsenyi, F.; Tarkanyi, F.

    1999-01-01

    Cross sections of deuteron induced nuclear reactions on natural molybdenum have been studied in the frame of a systematic investigation of charged particle induced nuclear reactions on metals for different applications. The excitation functions of 92m,95 Nb-, 93,94g,94m,95g,95m,96,99m Tc- and 99 Mo were measured up to 21 MeV deuteron energy by using stacked foil technique and activation method. The goal of this work was to study the production possibility of the medical important 94m,99m Tc- and 99 Mo-nuclides. Production of 99m Tc and 99 Mo is of importance for their use in nuclear medicine, whereas 94m Tc is of interest regarding quantification of kinetics of well-established 99m Tc-radiopharmaceuticals. The production possibilities of 99m Tc and 99 Mo above 20 MeV deuteron energies up to 50 MeV were estimated and was found that beside the proton induced reactions the deuteron induced reactions on enriched molybdenum target are very promising. (author)

  11. Uranium enrichment plans

    International Nuclear Information System (INIS)

    Gagne, R.W.; Thomas, D.C.

    1977-01-01

    The status of existing uranium enrichment contracts in the US is reviewed and expected natural uranium requirements for existing domestic uranium enrichment contracts are evaluated. Uncertainty in natural uranium requirements associated with requirements-type and fixed-commitment type contracts is discussed along with implementation of variable tails assay

  12. Fast neutron measurements with 7Li and 6Li enriched CLYC scintillators

    International Nuclear Information System (INIS)

    Giaz, A.; Blasi, N.; Boiano, C.; Brambilla, S.; Camera, F.; Cattadori, C.; Ceruti, S.; Gramegna, F.; Marchi, T.; Mattei, I.; Mentana, A.; Million, B.; Pellegri, L.; Rebai, M.; Riboldi, S.; Salamida, F.; Tardocchi, M.

    2016-01-01

    The recently developed Cs 2 LiYCl 6 :Ce (CLYC) crystals are interesting scintillation detectors not only for their gamma energy resolution (<5% at 662 keV) but also for their capability to identify and measure the energy of both gamma rays and fast/thermal neutrons. The thermal neutrons were detected by the 6 Li(n,α)t reaction while for the fast neutrons the 35 Cl(n,p) 35 S and 35 Cl(n,α) 32 P neutron-capture reactions were exploited. The energy of the outgoing proton or α particle scales linearly with the incident neutron energy. The kinetic energy of the fast neutrons can be measured using both the Time Of Flight (TOF) technique and using the CLYC energy signal. In this work, the response to monochromatic fast neutrons (1.9–3.8 MeV) of two CLYC 1″×1″ crystals was measured using both the TOF and the energy signal. The observables were combined to identify fast neutrons, to subtract the thermal neutron background and to identify different fast neutron-capture reactions on 35 Cl, in other words to understand if the detected particle is an α or a proton. We performed a dedicated measurement at the CN accelerator facility of the INFN Legnaro National Laboratories (Italy), where the fast neutrons were produced by impinging a proton beam (4.5, 5.0 and 5.5 MeV) on a 7 LiF target. We tested a CLYC detector 6 Li-enriched at about 95%, which is ideal for thermal neutron measurements, in parallel with another CLYC detector 7 Li-enriched at more than 99%, which is suitable for fast neutron measurements.

  13. Evidence for two narrow pp resonances at 2020 MeV and 2200 MeV

    CERN Document Server

    Benkheiri, P; Bouquet, B; Briandet, P; D'Almagne, B; Dang-Vu, C; De Rosny, G; Eisenstein, B I; Ferrer, A; Fleury, P; Grossetête, B; Irwin, G; Jacholkowski, A; Lahellec, A; Nguyen, H; Petroff, P; Richard, F; Rivet, P; Roudeau, P; Rougé, A; Rumpf, M; Six, J; Thénard, J M; Treille, D; Volte, A; Yaffe, D; Yiou, T P; Yoshida, H

    1977-01-01

    From the study of the reaction pi /sup -/p to p/sub F/pp pi /sup -/ using a fast proton (p/sub F/) trigger device in the CERN Omega spectrometer, the authors find evidence for two narrow pp states produced mainly in association with a Delta degrees (1232) and a N degrees (1520). The statistical significance of each peak is greater than 6 standard deviations. Masses and natural widths of these resonances are respectively M/sub 1/=2020+or-3 MeV, Gamma /sub 1 /=24+or-12 MeV and M/sub 2/=2204+or-5 MeV, Gamma /sub 2/=16/sub -16 //sup +20/ MeV. The data are consistent with a small production of the narrow approximately 1935 MeV resonance already reported. Production cross sections for these new pp resonances are given. (8 refs).

  14. Positron acceleration to 200 MeV

    International Nuclear Information System (INIS)

    Leboutet, H.

    1983-01-01

    220 MeV is the energy that has to be obtained in routine operation. A standard 12m girder with SLED II can give 220 MeV minus a few percent due to not riding at the crest of the wave. In order to have the 200 MeV with only one girder, a klystron at full power all the time would be required - kept brand new. Then, for safety it is necessary to use two klystrons as designated in the SLC design. Having two klystrons gives freedom for the choice of the best arrangement. Since there will be excess rf power, it can be traded against higher gradient, shorter waveguides, larger apertures (lower shunt impedence)

  15. Aspects of the historical development of targetry for heavy ions of 0.05-2000 A centre dot MeV at GSI

    CERN Document Server

    Folger, H

    1999-01-01

    The progressively improved GSI accelerators provide beams of heavy ions from energies of 0.05-2000 A centre dot MeV at high particle intensities now. Therefore, a wide variety of common and new heavy-ion target techniques had to be installed and developed during the past 25 years to prepare and characterize self-supported or backed heavy-ion-targets of chemical elements and compounds from hydrogen (as polyethylene) to uranium. The thickness ranged from 2x10 sup - sup 6 to 20 g/cm sup 2 for beam spots of about 5 mm in diameter. Homogeneity, surface structure or individual shape had to be adapted to the needs of each experiment. Special setups were required for targets of poisonous materials, of highly enriched stable isotopes or those of radioactive species in minute amounts. The capability of thin-layer technologies was as well applied to prepare and measure stripper foils or various high-vacuum deposits for experimental or accelerator purposes. The development of different rotating target wheels and control ...

  16. 200 MeV proton scattering on nuclei. Energetic proton analysis at large angle

    International Nuclear Information System (INIS)

    Chaigne, G.

    1983-01-01

    By means of a magnetic spectrometer for which has been realized an acceptance's programme, cross-sections for backward emission have been measured (100 MeV till the cinematic limit) (102 0 to 106 0 ) in the interaction proton-nucleus at 200 MeV from light, medium and heavy target. Our experimental set-up used from a polyethylene target (CH2) allowed to obtain, for the elastic cross-section (p,p), values in agreement with those ones determined by an analyse in phase-shift at 200 MeV. A comparison of our experimental spectra with the theory based on the Q.T.B.S. model (Quasi Two Body Scaling) and on a more conventional one of intranuclear cascades showed that the knock out mechanisms inside the nucleus are always unknown [fr

  17. Developments in uranium enrichment

    International Nuclear Information System (INIS)

    Mohrhauer, H.

    1995-01-01

    The enrichment services market is still characterized by overcapacities. While consumption worldwide will rise by some 15% to 39,000 t SWU/a over the next ten years, capacities amount to nearly 50,000 t SWU/a. The price for enrichment services probably has reached its all time low. Prices below U.S. $ 100/kg SWU are not likely to cover costs even of the economically most advanced enrichment processes. Urenco has prepared for the difficult enrichment business in the years to come by streamlining and cost cutting measures. The company intends to hold and increase its share of more than 10% in the world market. The uranium enrichment plant of Gronau will be expanded further. Expansion beyond 1000 t is subject to another permit being granted under the Atomic Energy Act, an application for which was filed in December 1994. Centrifuge technology is the superior enrichment technology, i.e., there is still considerable potential for further development. Construction of enrichment plants employing the centrifuge technology in the United States and in France is being pursued in various phases, from feasibility studies to licensing procedures. Before these plants could be implemented, however, considerable problems of organization would have to be solved, and the market would have to change greatly, respectively. The laser process, at the present time, does not seem to be able to develop into a major industrial competitor. (orig.) [de

  18. Shielding calculations for a 30 MeV proton accelerator

    International Nuclear Information System (INIS)

    Nandy, Maitreyee; Sarkar, P.K.

    2003-01-01

    Full text: The thickness of the shield, made of ordinary concrete, required to reduce the equivalent dose rate below the maximum permissible limit and to ensure safe operation of a 30 MeV proton accelerator has been estimated using the Moyer model. Required double differential neutron yield from thick stopping targets has been calculated for several reactions to be used for production of 67 Ga, 111 In, 123 I and 201 Tl radioisotopes. The neutron emission at 0 deg and 90 deg angles with respect to the incident beam direction is estimated using the hybrid model code ALICE91 which considers preequilibrium and equilibrium emissions from the target+projectile composite system. From this neutron yield the equivalent neutron dose rate at unit distance is determined using the ICRP recommended flux-to-dose conversion factors

  19. TRIGA low enrichment fuel

    International Nuclear Information System (INIS)

    Gietzen, A.

    1993-01-01

    Sixty TRIGA reactors have been sold and the earliest of these are now passing twenty years of operation. All of these reactors use the uranium zirconium hydride fuel (UZrH) which provides certain unique advantages arising out of its large prompt negative temperature coefficient, very low fission product release, and high temperature capability. Eleven of these Sixty reactors are conversions from plate fuel to TRIGA fuel which were made as a result of these advantages. With only a few exceptions, TRIGA reactors have always used low-enriched uranium (LEU) fuel with an enrichment of 19.9%. The exceptions have either been converted from the standard low-enriched fuel to the 70% enriched FLIP fuel in order to achieve extended lifetime, or are higher powered reactors which were designed for long life using 93%-enriched uranium during the time when the use and export of highly enriched uranium (HEU) was not restricted. The advent of international policies focusing attention on nonproliferation and safeguards made the HEU fuels obsolete. General Atomic immediately undertook a development effort (nearly two years ago) in order to be in a position to comply with these policies for all future export sales and also to provide a low-enriched alternative to fully enriched plate-type fuels. This important work was subsequently partially supported by the U.S. Department of Energy. The laboratory and production tests have shown that higher uranium densities can be achieved to compensate for reducing the enrichment to 20%, and that the fuels maintain the characteristics of the very thoroughly proven standard TRIGA fuels. In May of 1978, General Atomic announced that these fuels were available for TRIGA reactors and for plate-type reactors with power levels up to 15 MW with General Atomic's standard commercial warranty

  20. TRIGA low enrichment fuel

    International Nuclear Information System (INIS)

    Gietzen, A.

    1993-01-01

    Sixty TRIGA reactors have been sold and the earliest of these are now passing twenty years of operation. All of these reactors use the uranium-zirconium hydride fuel (UZrH) which provides certain unique advantages arising out of its large prompt negative temperature coefficient, very low fission product release, and high temperature capability. Eleven of these Sixty reactors are conversions from plate fuel to TRIGA fuel which were made as a result of these advantages. With only a few exceptions, TRIGA reactors have always used low-enriched-uranium (LEU) fuel with an enrichment of 19.9%. The exceptions have either been converted from the standard low-enriched fuel to the 70% enriched FLIP fuel in order to achieve extended lifetime, or are higher powered reactors which were designed for long life using 93%-enriched uranium during the time when the use and export of highly enriched uranium (HEU) was not restricted. The advent of international policies focusing attention on nonproliferation and safeguards made the HEU fuels obsolete. General Atomic immediately undertook a development effort (nearly two years ago) in order to be in a position to comply with these policies for all future export sales and also to provide a low-enriched alternative to fully enriched plate-type fuels. This important work was subsequently partially supported by the U.S. Department of Energy. The laboratory and production tests have shown that higher uranium densities can be achieved to compensate for reducing the enrichment to 20%, and that the fuels maintain the characteristics of the very thoroughly proven standard TRIGA fuels. In May of 1978, General Atomic announced that these fuels were available for TRIGA reactors and for plate-type reactors with power levels up to 15 MW with GA's standard commercial warranty

  1. 208Pb(n,pxnγ) reactions for neutron energies up to 200 MeV

    International Nuclear Information System (INIS)

    Pavlik, A.; Vonach, H.

    1995-01-01

    The prompt gamma-radiation from the interaction of fast neutrons with enriched samples of 208 Pb was measured using the white neutron beam of the WNR facility at Los Alamos National Laboratory. The samples were positioned at about 40 m distance from the neutron production target. The spectra of the emitted gamma-rays were measured with a high-resolution HPGe detector. The incident neutron energy was determined by the time-of-flight method and the neutron fluence was measured with a 238 U fission chamber. In addition to the primary purpose of this experiment, the study of (n,xnγ) reactions leading to various lead isotopes, gamma transitions in the residual nuclei 207,205,203,201 Tl were analyzed. From these data gamma-production cross sections in the neutron energy range from the effective thresholds to 200 MeV were derived. The lines for the analysis had to be chosen carefully as the (n,pnxγ) cross sections are rather small and the interference with unresolved lead lines (even weak ones) would cause significant errors. The effect due to isomers with half-lives exceeding a few nanoseconds was taken into account and corrected for, if necessary. The measured cross sections were compared with the results of nuclear model calculations based on the exciton model for preequilibrium particle emission and the Hauser-Feshbach theory for compound nucleus decay. Unlike in the case of (n,xnγ) reactions the calculated results in general did not give a good description of the measured cross sections

  2. MeV fullerene impacts on mica

    Energy Technology Data Exchange (ETDEWEB)

    Doebeli, M.; Scandella, L. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Ames, F. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Hillock heights on mica irradiated with MeV C{sub 60} ions have been investigated systematically. Results show that the small range of secondary particles along the track plays a crucial role in defect production. (author) figs., tab., refs.

  3. <600> MeV synchro-cyclotron

    CERN Multimedia

    CERN PhotoLab

    1971-01-01

    One of the 14 pancakes of the new magnet coils for the 600 MeV synchro-cyclotron which were wound and coated with epoxy resin on the CERN site. These new coils will replace the present ones which have been in use for more than 14 years but are now showing signs of deteriorations.

  4. Hybridization Capture Using Short PCR Products Enriches Small Genomes by Capturing Flanking Sequences (CapFlank)

    DEFF Research Database (Denmark)

    Tsangaras, Kyriakos; Wales, Nathan; Sicheritz-Pontén, Thomas

    2014-01-01

    nucleotides) can result in enrichment across entire mitochondrial and bacterial genomes. Our findings suggest that some of the off-target sequences derived in capture experiments are non-randomly enriched, and that CapFlank will facilitate targeted enrichment of large contiguous sequences with minimal prior...

  5. Neutron cross-sections above 20 MeV for design and modeling of ...

    Indian Academy of Sciences (India)

    bination of a high-power, high-energy accelerator, a spallation target for neutron ... The development of the commercial critical reactors of today motivated a large effort on nuclear data up to about 20 MeV, and presently ..... facility in the world.

  6. Scattering of 30 MeV He3 from Re185

    Science.gov (United States)

    Garrett, P. E.; Phillips, A. A.; Demand, G. A.; Finlay, P.; Green, K. L.; Leach, K. G.; Schumaker, M. A.; Svensson, C. E.; Wong, J.; Hertenberger, R.; Wirth, H.-F.; Faestermann, T.; Krücken, R.; Burke, D. G.; Bettermann, L.; Braun, N.

    2009-01-01

    The scattering of 30 MeV He3 from a Re185 target has been investigated. The measured elastic scattering is in disagreement with calculations using common optical model parameter sets found in the literature. A new optical model parameter set has been determined that reproduces the data for both the elastic and the inelastic scattering channels.

  7. Study of inclusive proton spectra from 20 MeV deuteron breakup by bismuth

    International Nuclear Information System (INIS)

    Badiger, N.M.; Hallur, B.R.; Madhusoodhanan, T.; Sathyavathiamma, M.P.; Puttaswamy, N.G.; Darshan, V.P.; Sharma, H.; Chintalapudi, S.N.

    1997-01-01

    The breakup of deuteron into proton and neutron has been studied earlier to understand the breakup mechanism. Inclusive measurements show the expected broad bumps near the beam velocity. In the present experiment, the breakup of 20 MeV deuterons by bismuth target has been investigated

  8. Measurements and amplitude analysis of small angle pp polarization between 398 and 572 MeV

    CERN Document Server

    Aebischer, D; Greeniaus, L G; Hess, R; Junod, A; Lechanoine-Leluc, C; Nikles, J C; Rapin, D; Werren, D W

    1976-01-01

    Results are reported of an experiment performed at CERN in which a 38% polarized beam of protons was scattered on a carbon target and the measurements were made at 398, 455, 530 and 572 MeV in the CM angular range 4 degrees < Theta *<22 degrees . It is shown that the data are in good agreement with phase shift analysis predictions. (7 refs).

  9. Target preparation

    International Nuclear Information System (INIS)

    Hinn, G.M.

    1984-01-01

    A few of the more interesting of the 210 targets prepared in the Laboratory last year are listed. In addition the author continues to use powdered silver mixed with /sup 9,10/BeO to produce sources for accelerator radio dating of Alaskan and South Polar snow. Currently, he is trying to increase production by multiple sample processing. Also the author routinely makes 3 μg/cm 2 cracked slacked carbon stripper foils and is continuing research with some degree of success in making enriched 28 Si targets starting with the oxide

  10. The Supply of Medical Radioisotopes. Policy Options for Ensuring Long-term Supply Security of Molybdenum-99 and/or Technetium-99m Produced Without Highly Enriched Uranium Targets

    International Nuclear Information System (INIS)

    Westmacott, Chad; Cameron, Ron

    2012-01-01

    Following the shortages of the key medical radioisotopes, molybdenum-99 ( 99 Mo) and its daughter technetium-99m (' 99m Tc), the OECD-Nuclear Energy Agency (NEA) created the High-level Group on the Security of Supply of Medical Radioisotopes (HLG-MR). Since 2009, this group has identified the reasons for the isotope shortages and developed a policy approach to address the challenges to a long-term secure supply of these important medical isotopes. On top of the ongoing concerns related to long-term reliability, all current long-term major 99 Mo-producing nations have agreed to convert to using low-enriched uranium (LEU) targets for the production of 99 Mo. This decision was made based on important nonproliferation reasons; however, the conversion will have potential impacts on the global supply chain - both in terms of costs and available capacity. Recognising that conversion is important and will occur, and also recognising the need to ensure a long-term secure supply of 99 Mo/' 99m Tc, the NEA, along with stakeholders, examined potential policy options that could be used by to ensure a reliable supply of 99 Mo and/or ' 99m Tc produced without highly enriched uranium (HEU), consistent with the time frames and policies of the HLG-MR. This discussion paper provides the various policy options available to governments to encourage a reliable supply of 99 Mo and/or ' 99m Tc produced without HEU. The examination of these options was done through the lens of ensuring a reliable supply, consistent with the time frames and policies of the HLG-MR. The options described in this document are meant to meet this objective by taking one of three general actions: - Making the option of purchasing or producing non-HEU-based 99 Mo and/or ' 99m Tc more attractive. - Making the option of purchasing or producing HEU-based 99 Mo and/or ' 99m Tc less attractive. - Limiting access to HEU-based 99 Mo and/or ' 99m Tc. This paper presents the options in each category and provides some views

  11. Measurements of pp→π+d between 398 MeV and 572 MeV

    International Nuclear Information System (INIS)

    Aebischer, D.; Favier, B.; Greeniaus, L.G.; Hess, R.; Junod, A.; Lechanoine, C.; Nikles, J.-C.; Rapin, D.; Werren, D.W.

    1976-01-01

    The reaction pp→π + d was studied at incident proton energies of 398, 455, 497, 530 and 572 MeV. Measurements of dsigma/dΩ at 455 and 572 MeV show the presence of pion d-waves in the pion-deuteron system. Asymmetry measurements yield similar conclusions. Total cross-section measurements agree with recent fits to earlier data. (Auth.)

  12. Facility for the measurement of proton polarization in the range 50-70 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, M; Sakaguchi, H; Sakamoto, H; Ogawa, H; Cynshi, O; Kobayashi, S [Kyoto Univ. (Japan). Dept. of Physics; Kato, S [Osaka Univ., Toyonaka (Japan). Lab. of Nuclear Studies; Matsuoka, N; Hatanaka, K; Noro, T [Osaka Univ., Toyonaka (Japan). Research Center for Nuclear Physics

    1983-07-01

    A proton polarimetry facility based on silicon analyzers combined with high-purity germanium detectors is described. The scattering efficiency is 1.5 x 10/sup -5/ at 60 MeV with an effective analyzing power of 0.71 and the energy resolution is about 300 keV fwhm. The facility has succeeded in measuring the depolarization in p-/sup 13/C elastic scattering separated clearly from inelastic events. In order to use a silicon detector as an analyzer target, measurements of cross sections and analyzing powers have been performed at proton energies of 65, 60, 55, 50 and 45 MeV.

  13. Neutron-induced charged-particle emission studies below 100 MeV at WNR

    Energy Technology Data Exchange (ETDEWEB)

    Haight, R.C.; Lee, T.M.; Sterbenz, S.M. [and others

    1994-07-01

    Charged-particles produced by neutron bombardment of selected targets with Z=5 through 53 have been studied for neutron energies from 1 MeV to about 100 MeV using the spallation neutron source at WNR/LAMPF. Particle detection with energy measurement and particle identification is accomplished by two-element {Delta}E-E counters, three-element {Delta}E{sub l}-{Delta}E{sub 2}-E counters or with pulse-shape discrimination using scintillators directly in the neutron beam. The experimental techniques for these measurements are described and comparisons made among the different approaches. This presentation introduces five papers contributed to this conference.

  14. Neutron-induced charged-particle emission studies below 100 MeV at WNR

    International Nuclear Information System (INIS)

    Haight, R.C.; Lee, T.M.; Sterbenz, S.M.

    1994-01-01

    Charged-particles produced by neutron bombardment of selected targets with Z=5 through 53 have been studied for neutron energies from 1 MeV to about 100 MeV using the spallation neutron source at WNR/LAMPF. Particle detection with energy measurement and particle identification is accomplished by two-element ΔE-E counters, three-element ΔE l -ΔE 2 -E counters or with pulse-shape discrimination using scintillators directly in the neutron beam. The experimental techniques for these measurements are described and comparisons made among the different approaches. This presentation introduces five papers contributed to this conference

  15. Neutron-neutron quasifree scattering in nd breakup at 10 MeV

    Directory of Open Access Journals (Sweden)

    Malone R.C.

    2016-01-01

    We are conducting new measurements of the cross section for nn QFS in nd breakup. The measurements are performed at incident neutron beam energies below 20 MeV. The neutron beam is produced via the 2H(d, n3He reaction. The target is a deuterated plastic cylinder. Our measurements utilize time-of-flight techniques with a pulsed neutron beam and detection of the two emitted neutrons in coincidence. A description of our initial measurements at 10 MeV for a single scattering angle will be presented along with preliminary results. Also, plans for measurements at other energies with broad angular coverage will be discussed.

  16. Solid targets for 99mTc production on medical cyclotrons

    International Nuclear Information System (INIS)

    Hanemaayer, V.; Buckley, K.R.; Klug, J.; Ruth, T.J.; Schaffer, P.; Zeisler, S.K.; Benard, F.; Kovacs, M.; Leon, C.

    2014-01-01

    Recent disruptions in the molybdenum-technetium generator supply chain prompted a review of non-reactor based production methods for both 99 Mo and 99m Tc. Small medical cyclotrons (E p ∼ 16-24 MeV) are capable of producing Curie quantities of 99m Tc from isotopically enriched 100 Mo using the 100 Mo(p,2n) 99m Tc reaction. Unlike most other metallic target materials for routine production of medical radioisotopes, molybdenum cannot be deposited by reductive electroplating from aqueous salt solutions. To overcome this issue, we developed a new process for solid molybdenum targets based on the electrophoretic deposition of fine 100 Mo powder onto a tantalum plate, followed by high temperature sintering. The targets obtained were mechanically robust and thermally stable when irradiated with protons at high power density. (author)

  17. The competitive enrichment market

    International Nuclear Information System (INIS)

    Parks, J.W.; Huffman, F.C.

    1984-01-01

    With the enactment of the ''Private Ownership of Special Nuclear Materials Act'' in 1964, the U.S. Government made provisions to enter into the uranium enrichment services business. Since nuclear power was in its infancy and the Government was promoting its growth as well as trying to help U.S. industry sell reactors overseas, the initial contracts (Requirements Contracts) for enrichment services placed most of the risks associated with the supplying of the services on the Government. Projections of nuclear power additions continued to grow and in 1972 the Atomic Energy Commission (AEC) stopped contracting under Requirements Contracts in order to study which mode of contracting best suited the commercial development of the industry. In mid-1973, the AEC introduced the Long-Term Fixed Commitment (LTFC) contract which shifted the risk to the customer. By mid-1974, AEC had contracts which completely used the enrichment capacity of its complex and refused to accept requests for additional contracts. This action further convinced European nations that they should continue to develop their own enrichment capacity and resulted in the EURODIF and URENCO projects. Before this time the U.S. supplied 100% of the world market for enriching services

  18. Enrichment: Dealing with overcapacity

    International Nuclear Information System (INIS)

    Peterson, C.H.

    1989-01-01

    Today's surplus of enrichment capacity will continue until at least the end of this century. This will challenge the ingenuity of the separative work unit (SWU) suppliers as they attempt to keep market share and remain profitable in a very competitive marketplace. The utilities will be faced with attractive choices, but making the best choice will require careful analysis and increased attention to market factors. Current demand projections will probably prove too high to the extent that more reactors are canceled or delayed. The DOE has the vast majority of the unused capacity, so it will feel the most immediate impact of this large surplus in productive capacity. The DOE has responded to these market challenges by planning another reorganization of its enriching operations. Without a major agreement among the governments affected by the current surplus in enrichment capacity, the future will see lower prices, more competitive terms, and the gradual substitution of centrifuge or laser enrichment for the gaseous diffusion plants. The competition that is forcing the gaseous diffusion prices down to marginal cost will provide the long-term price basis for the enrichment industry

  19. Radiological safety research of food irradiation with 7.5 MeV X-rays

    International Nuclear Information System (INIS)

    Yang Bin; Tang Weidong; Zhang Yue; Xu Tao; Jin Jianqiao; Ye Mingyang

    2012-01-01

    China and America both have 7.5 MeV high energy X-ray accelerator. The radiological safety of food irradiated with 7.5 MeV X-rays (bremsstrahlung) has been investigated. Samples of meat and meat ash were located in a large volume of fresh meat at the position of the highest photoneutron fluence and irradiated to an X-ray dose of 15 kGy, twice the maximum dose allowed by the US FDA for meat irradiation. An evaluation of the corresponding radiation exposure from ingestion of the irradiated product has been compared to natural background radiation. The paper concludes that the risk to individuals from intake of food irradiated with X-rays from 7.5 MeV electrons, even with a broad energy spectrum, would be trivial. The common target materials are Au, Ta and W. The U.S, requires only Au and Ta can be used as food irradiation target materials and China has not yet relevant provisions. The first 7.5 MeV accelerator for food irradiation in China is under built, and will do the explore research for the choice of target material. (authors)

  20. Study of the D(p,π+)T and 9Be(p,π+)10Be from 400 to 800MeV

    International Nuclear Information System (INIS)

    Aslanides, E.; Bauer, T.; Bertini, R.; Beurtey, R.; Bimbot, L.; Bing, O.; Boudard, A.; Brochard, F.; Bruge, G.; Catz, H.; Chaumeaux, A.; Couvert, P.; Duchazeaubeneix, J.C.; Duhm, H.; Garreta, D.; Gorodetzky, P.; Habault, J.; Hibou, F.; Igo, G.; Le Bornec, Y.; Lugol, J.C.; Matoba, M.; Tatischeff, B.; Terrien, Y.

    Pion production on CD 2 and 9 Be targets has been observed using the high resolution, energy loss, spectrometer SPES I. Differential cross sections for the D(p,π + ) reaction have been determined at 410, 605 and 809MeV and for the 9 Be(p,π + ) reaction at 410 and 605MeV. The 3.37MeV (2 + ) state in 10 Be is populated preferentially, but a significant part of the transition strength seems to populate the ground state and the higher lying multiplets at about 6.1MeV, 7.4MeV and 9.4MeV [fr

  1. Proton-nucleus interactions at 640 MeV accompanied by backward emission of energetic protons

    International Nuclear Information System (INIS)

    Komarov, V.I.; Kosarev, E.G.; Mueller, H.; Netzband, D.; Toneev, V.D.; Stiehler, T.; Tesch, S.; Gudima, K.K.; Mashnik, S.G.

    1979-03-01

    Spectra of protons of energies between 50 and 145 MeV emitted from carbon have been measured at angles from 105 0 to 160 0 with respect to the 640 MeV proton beam. The measurements have been carried out both inclusively and in coincidence with protons emitted at forward angles up to +- 40 0 with energies from 255 to 330 MeV. This energy interval has been chosen in accordance with the kinematics of quasifree scattering on two-nucleon groups. Inclusive differential cross sections at 140 0 and coincidence cross sections at the angle pair (-12 0 , 122 0 ) have also been measured with Be, Al, Cu and Pb targets. The data have been compared with the predictions of several models. (author)

  2. Calibration in photon radiation fields with energies above 3 MeV

    International Nuclear Information System (INIS)

    Bueermann, L.

    1997-01-01

    For determination of the response of dosemeters and dose ratemeters for photon energies above 3 MeV, the PTB uses reference radiation fields generated via the nuclear reactions 12 (p, p' γ) 12 C (4.4 MeV) and 19 F(p,αγ) 16 O (6-7 MeV). As a maximum, kerma rates of 1 mGy/h released in air can be achieved at 1 m distance from the target. The air kerma in the reference fields is determined with two different methods, i.e. by spectrometry using a Ge detector, and by ionometry using a graphite cavity ionisation chamber. The total uncertainty of the value determined for the air kerma (collision radiation) in the reference fields is 50% at a confidence level of 68.3%. (orig./CB) [de

  3. The ANL 50 MeV H- Injector: 35 year anniversary

    International Nuclear Information System (INIS)

    Stipp, V.; Brumwell, F.; McMichael, G.

    1996-01-01

    The H - Injector at ANL consists of a 750 keV Cockcroft-Walton preaccelerator and an Alvarez type 50 MeV Linac. The accelerator was originally constructed as the source of protons for the Zero Gradient Synchrotron (ZGS). The first proton beam was extracted from the preaccelerator in 1961. The accelerator is presently used as the injector for the Intense Pulsed Neutron Source (IPNS), a 500 MeV rapid cycling synchrotron with a spallation-neutron target. During most of the time since turn-on over 15 years ago, the IPNS facility availability has rarely dropped below 90% and has averaged 95% over the last ten years. During the same period, the 50 MeV injector availability has averaged 99%. Performance and improvements over the 35 year period is discussed

  4. Elastic and inelastic scattering of 2 to 10 MeV protons by lithium isotopes

    International Nuclear Information System (INIS)

    Laurat, M.

    1969-01-01

    A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten μg/cm 2 ) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of 8 Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [fr

  5. 14 MeV proton activation analysis

    International Nuclear Information System (INIS)

    Constantinescu, B.; Ivanov, E.; Plostinaru, D.; Popa-Nemoiu, A.; Pascovichi, G.

    1985-01-01

    A fast nuclear nondestructive method for protein analysis using the 14 MeV proton activation has been developed. The total nitrogen content was measured through the reaction: 14 N (p,n) 14 O, (Tsub(1/2)=71 s). The 14 O activity was detected by means of its characteristic 2.312 MeV gamma-ray line with a NaI(Tl) detector. For a fast determination of a large number of samples a mechanized sistem reacting a rate of one sample per minute has been developed. The laboratory electronics comprises a multichannel analyser, a PDP computer and an electronic module comtroller. Comparison of the results obtained by the method described and the classical Kjeldal technique for samples of various cereal grains (soya bean seads, wheat, barley and corn) showed good correlation. A problem of the analysis of the whole protein region on corn and soya-bean seads, where this region is thicker (0,2 - 2 mm), is mentioned. In this case flour was proposed to be used to obtain a protein homogeneous sample and the irradiaton dose for a sample was about 33,000 Gy, mainly (99%) from protons (27 s x 100 nA x 14 MeV)

  6. Laser and gas centrifuge enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Heinonen, Olli [Senior Fellow, Belfer Center for Science and International Affairs, Harvard Kennedy School, Cambridge, Massachusetts (United States)

    2014-05-09

    Principles of uranium isotope enrichment using various laser and gas centrifuge techniques are briefly discussed. Examples on production of high enriched uranium are given. Concerns regarding the possibility of using low end technologies to produce weapons grade uranium are explained. Based on current assessments commercial enrichment services are able to cover the global needs of enriched uranium in the foreseeable future.

  7. Momentum transfer with light ions at energies from 70 MeV to 1000 MeV

    International Nuclear Information System (INIS)

    Saint Laurent, F.; Conjeaud, M.; Dayras, R.; Harar, S.; Oeschler, H.; Volant, C.

    1982-01-01

    Angular correlations of fission fragments induced by bombarding a 232 Th target with protons, deuterons and alpha particles of energies from 70 MeV to 1000 MeV have been measured. They give information about the forward momentum imparted to the fissioning nuclei. We present the average values of the transferred linear momentum ([p vertical stroke vertical stroke ]) as a function of the incident energy and propose a classification into three regimes of dominating processes leading to fission: (I) low-energy behaviour, for E/A less than 10 MeV/u [p vertical stroke vertical stroke ]/psub(i) approx. equal to 1. (II) Between 10 MeV/u and about 70 MeV/u, [p vertical stroke vertical stroke ]/psub(i) decreases progressively down to 0.5 but remains proportional to the projectile mass. (III) The region between 70 MeV/u and about 1000 MeV/u corresponds to a transition region where the projectiles, whatever their masses, tend to transfer the same momentum. (orig.)

  8. Elastic scattering of polarized protons by 20Ne between 4.5 Mev and 5.5 Mev

    International Nuclear Information System (INIS)

    Avila A, O.L.

    1979-01-01

    Starting with the study of 20 Ne(p,p) 20 nuclear reaction, we obtained information about the nuclear structure of 21 Na. The experiment was made at Notre Dame University; a target of 20 Ne was bombarded with polarized protons, changing the incident energy of them between 4.5 Mev and 5.5 Mev at intervals of 10 keV. Fourteen detectors were set covering angles from 35 degrees until 165 degrees, with intervals of 10 degrees each. In this form measurements for computing polarization and differential sections were obtained, with them an analysis of runnings of phase was made, and the parameters associated with two of the excited levels of the composed formed nucleous 21 Na, that are viewed as resonances in the section were settled; those resonances correspond to a level Psub(3/2) of energy excitation 6.877, a total width of 36 keV, and a level Fsub(7/2) of energy excitation 6.992 and total width of 48 keV. I hope that these results will be part of a set of values that will be utilized in order to confront them with the existent nuclear models. (author)

  9. Oxygen enrichment incineration

    International Nuclear Information System (INIS)

    Kim, Jeong Guk; Yang, Hee Chul; Park, Geun Il; Kim, Joon Hyung

    2000-10-01

    Oxygen enriched combustion technology has recently been used in waste incineration. To apply the oxygen enrichment on alpha-bearing waste incineration, which is being developed, a state-of-an-art review has been performed. The use of oxygen or oxygen-enriched air instead of air in incineration would result in increase of combustion efficiency and capacity, and reduction of off-gas product. Especially, the off-gas could be reduced below a quarter, which might reduce off-gas treatment facilities, and also increase an efficiency of off-gas treatment. However, the use of oxygen might also lead to local overheating and high nitrogen oxides (NOx) formation. To overcome these problems, an application of low NOx oxy-fuel burner and recycling of a part of off-gas to combustion chamber have been suggested

  10. Oxygen enrichment incineration

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Guk; Yang, Hee Chul; Park, Geun Il; Kim, Joon Hyung

    2000-10-01

    Oxygen enriched combustion technology has recently been used in waste incineration. To apply the oxygen enrichment on alpha-bearing waste incineration, which is being developed, a state-of-an-art review has been performed. The use of oxygen or oxygen-enriched air instead of air in incineration would result in increase of combustion efficiency and capacity, and reduction of off-gas product. Especially, the off-gas could be reduced below a quarter, which might reduce off-gas treatment facilities, and also increase an efficiency of off-gas treatment. However, the use of oxygen might also lead to local overheating and high nitrogen oxides (NOx) formation. To overcome these problems, an application of low NOx oxy-fuel burner and recycling of a part of off-gas to combustion chamber have been suggested.

  11. Digital neutron/gamma discrimination with an organic scintillator at energies between 1 MeV and 100 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Comrie, A.C. [Department of Physics, University of Cape Town, Rondebosch 7700 (South Africa); Buffler, A., E-mail: andy.buffler@uct.ac.za [Department of Physics, University of Cape Town, Rondebosch 7700 (South Africa); Smit, F.D. [iThemba LABS, Somerset West 7129 (South Africa); Wörtche, H.J. [INCAS" 3, Dr. Nassaulaan 9. 9400 AT Assen (Netherlands)

    2015-02-01

    Three different digital implementations of pulse shape discrimination for pulses from an EJ301 liquid scintillator detector are presented, and illustrated with neutrons and gamma-rays produced by an Am–Be radioisotopic source, a D–T generator and beams produced by cyclotron-accelerated protons of energies 42, 62 and 100 MeV on a Li target. A critical comparison between the three methods is provided.

  12. Centrifuge enrichment program

    International Nuclear Information System (INIS)

    Astley, E.R.

    1976-01-01

    Exxon Nuclear has been active in privately funded research and development of centrifuge enrichment technology since 1972. In October of 1975, Exxon Nuclear submitted a proposal to design, construct, and operate a 3000-MT SWU/yr centrifuge enrichment plant, under the provisions of the proposed Nuclear Fuel Assurance Act of 1975. The U.S. Energy Research and Development Administration (ERDA) accepted the proposal as a basis for negotiation. It was proposed to build a 1000-MT SWU/yr demonstration increment to be operational in 1982; and after successful operation for about one year, expand the facilities into a 3000-MT SWU/yr plant. As part of the overall centrifuge enrichment plant, a dedicated centrifuge manufacturing plant would be constructed; sized to support the full 3000-MT SWU/yr plant. The selection of the centrifuge process by Exxon Nuclear was based on an extremely thorough evaluation of current and projected enrichment technology; results show that the technology is mature and the process will be cost effective. The substantial savings in energy (about 93%) from utilization of the centrifuge option rather than gaseous diffusion is a compelling argument. As part of this program, Exxon Nuclear has a large hardware R and D program, plus a prototype centrifuge manufacturing capability in Malta, New York. To provide a full-scale machine and limited cascade test capability, Exxon Nuclear is constructing a $4,000,000 Centrifuge Test Facility in Richland, Washington. This facility was to initiate operations in the Fall of 1976. Exxon Nuclear is convinced that the centrifuge enrichment process is the rational selection for emergence of a commercial enrichment industry

  13. Elastic Neutron Scattering at 96 MeV from {sup 12}C and {sup 208}Pb

    Energy Technology Data Exchange (ETDEWEB)

    Klug, J.; Blomgren, J.; Atac, A. [and others

    2003-04-01

    A facility for detection of scattered neutrons in the energy interval 50-130 MeV, SCANDAL (SCAttered Nucleon Detection AssembLy), has recently been installed at the 20-180 MeV neutron beam line of the The Svedberg Laboratory, Uppsala. Elastic neutron scattering from {sup 12}C and {sup 208}Pb has been studied at 96 MeV in the 10-70 deg interval. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. The present experiment represents the highest neutron energy where the ground state has been resolved from the first excited state in neutron scattering. A novel method for normalization of the absolute scale of the cross section has been used. The estimated uncertainty, 3 %, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. The results are compared with modern optical model predictions, based on phenomenology or microscopic nuclear theory.

  14. US enrichment reduction studies

    International Nuclear Information System (INIS)

    1979-06-01

    A major national program, the Reduced Enrichment Research and Test Reactor (RERTR) Program, is currently under way in the U.S., centered at the Argonne National Laboratory (ANL), to reduce the potential of research and test reactor fuels for increasing the proliferation of nuclear explosive devices. The main objective of the program is to provide the technical means by which the uranium enrichment to be used in these reactors can be reduced to less than 20% without significant economic and performance penalties. The criteria, basis and goals of the program are consistent with the results of a number of case studies which have been performed as part of the program

  15. Advanced uranium enrichment processes

    International Nuclear Information System (INIS)

    Clerc, M.; Plurien, P.

    1986-01-01

    Three advanced Uranium enrichment processes are dealt with in the report: AVLIS (Atomic Vapour LASER Isotope Separation), MLIS (Molecular LASER Isotope Separation) and PSP (Plasma Separation Process). The description of the physical and technical features of the processes constitutes a major part of the report. If further presents comparisons with existing industrially used enrichment technologies, gives information on actual development programmes and budgets and ends with a chapter on perspectives and conclusions. An extensive bibliography of the relevant open literature is added to the different subjects discussed. The report was drawn up by the nuclear research Centre (CEA) Saclay on behalf of the Commission of the European Communities

  16. Uranium Conversion & Enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-06

    The isotopes of uranium that are found in nature, and hence in ‘fresh’ Yellowcake’, are not in relative proportions that are suitable for power or weapons applications. The goal of conversion then is to transform the U3O8 yellowcake into UF6. Conversion and enrichment of uranium is usually required to obtain material with enough 235U to be usable as fuel in a reactor or weapon. The cost, size, and complexity of practical conversion and enrichment facilities aid in nonproliferation by design.

  17. Determination of the optimal conditions for simultaneous production of 73SE and 75SE radioisotopes in a 30 MeV cyclotron

    International Nuclear Information System (INIS)

    Pejman Rowshanfazad; Amirreza Jalilian; Mahsheed Sabet

    2004-01-01

    enrichment process, due to the presence of arsenic as 75 As(100%) in nature. On the other hand, chemical separation could be carried out in simple, inexpensive methods in a short time, due to the difference between target materials and the products. So the above reactions were taken to be the best choices according to the present conditions and facilities. 2 Cross Section Calculations for 75 As Reactions with Protons. Characterization of excitation function is a very important step for the determination of the projectile beam energy range. Excitation function can be determined by using computer codes such as ALICE (21) or experimental methods. In the present research, performed in the cyclotron department of Atomic Energy Organization of Iran (IBA, Cyclone-30), 75 As reaction cross-sections with protons were calculated for beam energy range of 3-30 MeV (this cyclotron can accelerate protons to 30 MeV energy) using ALICE code and the results were compared with previous experimental data given in the literature (19, 22, 23). The results of this comparison are shown in figure 1. Figure 1 shows a good agreement between the results of ALICE code and the experimental data. The three main reactions were 75 As(p, n) 75 Se, 75 As(p, pn) 74 Se and 75 As(p, 3n) 73 Se. Production of 75 Se began at about 2 MeV and reached its maximum around 12 MeV, where the reaction cross section was about 840 mb. Production of 74 As began around 13 MeV and reached its maximum at about 26 MeV, where the reaction cross section was about 170 mb. 74 As (which was considered as impurity) has a half life of 17.8 days, so it could be easily separated from the product by efficient chemical methods and it was not taken into account while energy selection. Production of 73 Se began at around 22 MeV proton energy and continued to increase while beam energy increased to 30 MeV, where the reaction cross section was about 550 mb. Thus, if the target thickness would be enough to reduce the proton energy from 22 MeV

  18. Measurement of (n,Xn) reaction cross sections at 96 MeV; Measure des sections efficaces (n,Xn) a 96 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Sagrado Garcia, Melle Inmaculada C. [Ecole Doctorale: SINEM, U.F.R. de Sciences, Universite de Caen/Basse-Normandie, Esplanade Paix14000 Caen (France)

    2006-10-15

    Nucleon induced reactions in the 20-200 MeV energy range are intensively studied since a long time. The evaporation and the pre-equilibrium processes correspond to an important contribution of the production cross section in these reactions. Several theoretical approaches have been proposed and their predictions must be tested. The experimental results shown in this work are the only complete set of data for the (n,Xn) reactions in this energy range. Neutron double differential cross section measurements using lead and iron targets for an incident neutron beam at 96 MeV were carried out at TSL Laboratory in Uppsala, Sweden. The measurements have been performed for the first time with an energy threshold of 2 MeV and for a wide angular range (15 angle - 98 angle). Neutrons have been detected using two independent setups, DECOI and DEMON and CLODIA and SCANDAL, in order to cover the whole energy range (2-100) MeV. The angular distributions, the differential cross sections and the total inelastic production cross sections have been calculated using the double differential cross sections. The comparison between the experimental data and the predictions given by two of the most popular simulation codes, GEANT3 and MCNPX, have been performed, as well as the comparison with the predictions of the microscopic simulation model DYWAN, selected for its treatment of nucleon-nucleon reactions. (author)

  19. Measurement of the polarization correlation coefficient in elastic pp scattering at 610 MeV

    International Nuclear Information System (INIS)

    Borisov, N.S.; Glonti, L.N.; Kazarinov, M.Yu.

    1977-01-01

    The polarization correlation coefficient Csub(nn) for elastic pp scattering at 610+-10 MeV was measured for four scattering angles: 40, 67, 78 and 90 deg (c.m.s.). A polarized proton beam with a maximum polarization of 0.39+-0.02 and a polarized proton target of the frozen type were used. The maximum polarization of the target was 0.97+-0.04. The experimental procedure is described in detail. The Csub(nn) measured are compared with the results of a phase analysis and the findings at 575 MeV obtained elsewhere. The Csub(nn) coefficients are shown to be valuable to discriminate alternative solutions of the phase analysis. The polarized proton targets of the frozen type, no accounting the complexity of their design, are emphasized to be rather reliable and convenient devices for conducting experiments at accelerators

  20. EXPERIMENTAL ANALYSES OF SPALLATION NEUTRONS GENERATED BY 100 MEV PROTONS AT THE KYOTO UNIVERSITY CRITICAL ASSEMBLY

    Directory of Open Access Journals (Sweden)

    CHEOL HO PYEON

    2013-02-01

    Full Text Available Neutron spectrum analyses of spallation neutrons are conducted in the accelerator-driven system (ADS facility at the Kyoto University Critical Assembly (KUCA. High-energy protons (100 MeV obtained from the fixed field alternating gradient accelerator are injected onto a tungsten target, whereby the spallation neutrons are generated. For neutronic characteristics of spallation neutrons, the reaction rates and the continuous energy distribution of spallation neutrons are measured by the foil activation method and by an organic liquid scintillator, respectively. Numerical calculations are executed by MCNPX with JENDL/HE-2007 and ENDF/B-VI libraries to evaluate the reaction rates of activation foils (bismuth and indium set at the target and the continuous energy distribution of spallation neutrons set in front of the target. For the reaction rates by the foil activation method, the C/E values between the experiments and the calculations are found around a relative difference of 10%, except for some reactions. For continuous energy distribution by the organic liquid scintillator, the spallation neutrons are observed up to 45 MeV. From these results, the neutron spectrum information on the spallation neutrons generated at the target are attained successfully in injecting 100 MeV protons onto the tungsten target.

  1. Measurement of photon showers in lead produced by electrons of 150 MeV

    International Nuclear Information System (INIS)

    Goeringer, H.; Eyss, H.J. von; Schoch, B.

    1976-01-01

    The photon energy spectra induced by 150 MeV electrons in lead were measured in the energy range from 40 MeV up to the primary electron energy. The target thickness was varied between 0.1 and 2.5 radiation lengths X 0 . The photons were analyzed by use of a technique based on deuteron photodisintegration. Differential and integral shower spectra are presented and compared with Monte Carlo calculations of Nagel and Messel et al., both interpolated to our primary energy of 150 MeV. The measured spectra show good agreement with these Monte Carlo calculations for the thickest target of 2.5X 0 and with calculated bremsstrahlung spectra for the thinnest target of 0.1X 0 . Considerable discrepancies, however, are found for medium target thicknesses in the range 0 . Around the shower maxima, the shower spectra are narrower and the maxima are shifted about 0.3-0.4X 0 to lower target thicknesses, furthermore the number of photons at the shower maxima are up to 50% higher than calculated. (Auth.)

  2. An Enriching Community.

    Science.gov (United States)

    Holland, Nancy A.; Burroughs, Jean

    2001-01-01

    Successful school-community partnerships in Volusia (Florida) Public Schools are the results of marketing creatively, meeting community members' needs, and bringing the right people together. The 3-year old program now offers students of all ages an expanding list of enrichment classes on many subjects for a nominal fee. (MLH)

  3. Uranium enrichment techniques

    International Nuclear Information System (INIS)

    Hamdoun, N.A.

    2007-01-01

    This article includes an introduction about the isotopes of natural uranium, their existence and the difficulty of the separation between them. Then it goes to the details of a number of methods used to enrich uranium: Gaseous Diffusion method, Electromagnetic method, Jet method, Centrifugal method, Chemical method, Laser method and Plasma method.

  4. Requirements for enrichment tools

    NARCIS (Netherlands)

    Boer, A.; Winkels, R.; Trompper, M.

    2016-01-01

    This report gives a high level overview of requirements for Enrichment tools in the Openlaws.eu project. Openlaws.eu aims to initiate a platform and develop a vision for Big Open Legal Data (BOLD): an open framework for legislation, case law, and legal literature from across Europe.

  5. Enriching the Catalog

    Science.gov (United States)

    Tennant, Roy

    2004-01-01

    After decades of costly and time-consuming effort, nearly all libraries have completed the retrospective conversion of their card catalogs to electronic form. However, bibliographic systems still are really not much more than card catalogs on wheels. Enriched content that Amazon.com takes for granted--such as digitized tables of contents, cover…

  6. Cross section ratio and angular distributions of the reaction p + d → {sup 3}He + η at 48.8 MeV and 59.8 MeV excess energy

    Energy Technology Data Exchange (ETDEWEB)

    Adlarson, P.; Calen, H.; Fransson, K.; Gullstroem, C.O.; Heijkenskjoeld, L.; Hoeistad, B.; Johansson, T.; Marciniewski, P.; Redmer, C.F.; Wolke, M.; Zlomanczuk, J. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); Augustyniak, W.; Marianski, B.; Morsch, H.P.; Trzcinski, A.; Zupranski, P. [National Centre for Nuclear Research, Department of Nuclear Physics, Warsaw (Poland); Bardan, W.; Ciepal, I.; Czerwinski, E.; Hodana, M.; Jany, A.; Jany, B.R.; Jarczyk, L.; Kamys, B.; Kistryn, S.; Krzemien, W.; Magiera, A.; Moskal, P.; Ozerianska, I.; Podkopal, P.; Rudy, Z.; Skurzok, M.; Smyrski, J.; Wronska, A.; Zielinski, M.J. [Jagiellonian University, Institute of Physics, Krakow (Poland); Bashkanov, M.; Clement, H.; Doroshkevich, E.; Perez del Rio, E.; Pricking, A.; Skorodko, T.; Wagner, G.J. [Eberhard-Karls-Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Physikalisches Institut der Universitaet Tuebingen, Kepler Center fuer Astro- und Teilchenphysik, Tuebingen (Germany); Bergmann, F.S.; Demmich, K.; Goslawski, P.; Huesken, N.; Khoukaz, A.; Passfeld, A.; Taeschner, A. [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Berlowski, M.; Stepaniak, J. [National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Bhatt, H.; Lalwani, K.; Varma, R. [Indian Institute of Technology Bombay, Department of Physics, Mumbai, Maharashtra (India); Buescher, M.; Engels, R.; Goldenbaum, F.; Hejny, V.; Khan, F.A.; Lersch, D.; Lorentz, B.; Maier, R.; Ohm, H.; Prasuhn, D.; Schadmand, S.; Sefzick, T.; Stassen, R.; Sterzenbach, G.; Stockhorst, H.; Stroeher, H.; Wurm, P.; Zurek, M. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Coderre, D.; Ritman, J. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Ruhr-Universitaet Bochum, Institut fuer Experimentalphysik I, Bochum (Germany); Erven, A.; Erven, W.; Kemmerling, G.; Kleines, H.; Wuestner, P. [Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Forschungszentrum Juelich, Zentralinstitut fuer Engineering, Elektronik und Analytik, Juelich (Germany); Eyrich, W.; Hauenstein, F.; Krapp, M.; Zink, A. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); Fedorets, P. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Foehl, K. [Justus-Liebig-Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); Goswami, A. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); Indian Institute of Technology Indore, Department of Physics, Indore, Madhya Pradesh (India); Grigoryev, K. [Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (Germany); RWTH Aachen, III. Physikalisches Institut B, Physikzentrum, Aachen (Germany); Petersburg Nuclear Physics Institute, High Energy Physics Division, Leningrad district (Russian Federation); Kirillov, D.A.; Piskunov, N.M. [Joint Institute for Nuclear Physics, Veksler and Baldin Laboratory of High Energiy Physics, Moscow region (Russian Federation); Klos, B.; Stephan, E.; Weglorz, W. [University of Silesia, August Chelkowski Institute of Physics, Katowice (Poland); Kulessa, P.; Pysz, K.; Siudak, R.; Szczurek, A. [Polish Academy of Sciences, The Henryk Niewodniczanski Institute of Nuclear Physics, Krakow (Poland); Kupsc, A.; Pszczel, D. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (Sweden); National Centre for Nuclear Research, High Energy Physics Department, Warsaw (Poland); Mikirtychiants, M. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (Germany); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (DE); Ruhr-Universitaet Bochum, Institut fuer Experimentalphysik I, Bochum (DE); Petersburg Nuclear Physics Institute, High Energy Physics Division, Leningrad district (RU); Pyszniak, A. [Uppsala University, Division of Nuclear Physics, Department of Physics and Astronomy, Box 516, Uppsala (SE); Jagiellonian University, Institute of Physics, Krakow (PL); Roy, A. [Indian Institute of Technology Indore, Department of Physics, Indore, Madhya Pradesh (IN); Sawant, S. [Indian Institute of Technology Bombay, Department of Physics, Mumbai, Maharashtra (IN); Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (DE); Serdyuk, V. [Forschungszentrum Juelich, Institut fuer Kernphysik, Juelich (DE); Forschungszentrum Juelich, Juelich Center for Hadron Physics, Juelich (DE); Joint Institute for Nuclear Physics, Dzhelepov Laboratory of Nuclear Problems, Moscow region (RU); Sopov, V. [State Scientific Center of the Russian Federation, Institute for Theoretical and Experimental Physics, Moscow (RU); Yamamoto, A. [High Energy Accelerator Research Organization KEK, Tsukuba, Ibaraki (JP); Yurev, L. [Joint Institute for Nuclear Physics, Dzhelepov Laboratory of Nuclear Problems, Moscow region (RU); Zabierowski, J. [National Centre for Nuclear Research, Department of Cosmic Ray Physics, Lodz (PL); Collaboration: WASA-at-COSY Collaboration

    2014-06-15

    We present new data for angular distributions and on the cross section ratio of the p+d → {sup 3}He + η reaction at excess energies of Q = 48.8 MeV and Q = 59.8 MeV. The data have been obtained at the WASA-at-COSY experiment (Forschungszentrum Juelich) using a proton beam and a deuterium pellet target. While the shape of obtained angular distributions show only a slow variation with the energy, the new results indicate a distinct and unexpected total cross section fluctuation between Q = 20 MeV and Q = 60 MeV, which might indicate the variation of the production mechanism within this energy interval. (orig.)

  7. Cross section ratio and angular distributions of the reaction p + d → 3He + η at 48.8 MeV and 59.8 MeV excess energy

    International Nuclear Information System (INIS)

    Adlarson, P.; Calen, H.; Fransson, K.; Gullstroem, C.O.; Heijkenskjoeld, L.; Hoeistad, B.; Johansson, T.; Marciniewski, P.; Redmer, C.F.; Wolke, M.; Zlomanczuk, J.; Augustyniak, W.; Marianski, B.; Morsch, H.P.; Trzcinski, A.; Zupranski, P.; Bardan, W.; Ciepal, I.; Czerwinski, E.; Hodana, M.; Jany, A.; Jany, B.R.; Jarczyk, L.; Kamys, B.; Kistryn, S.; Krzemien, W.; Magiera, A.; Moskal, P.; Ozerianska, I.; Podkopal, P.; Rudy, Z.; Skurzok, M.; Smyrski, J.; Wronska, A.; Zielinski, M.J.; Bashkanov, M.; Clement, H.; Doroshkevich, E.; Perez del Rio, E.; Pricking, A.; Skorodko, T.; Wagner, G.J.; Bergmann, F.S.; Demmich, K.; Goslawski, P.; Huesken, N.; Khoukaz, A.; Passfeld, A.; Taeschner, A.; Berlowski, M.; Stepaniak, J.; Bhatt, H.; Lalwani, K.; Varma, R.; Buescher, M.; Engels, R.; Goldenbaum, F.; Hejny, V.; Khan, F.A.; Lersch, D.; Lorentz, B.; Maier, R.; Ohm, H.; Prasuhn, D.; Schadmand, S.; Sefzick, T.; Stassen, R.; Sterzenbach, G.; Stockhorst, H.; Stroeher, H.; Wurm, P.; Zurek, M.; Coderre, D.; Ritman, J.; Erven, A.; Erven, W.; Kemmerling, G.; Kleines, H.; Wuestner, P.; Eyrich, W.; Hauenstein, F.; Krapp, M.; Zink, A.; Fedorets, P.; Foehl, K.; Goswami, A.; Grigoryev, K.; Kirillov, D.A.; Piskunov, N.M.; Klos, B.; Stephan, E.; Weglorz, W.; Kulessa, P.; Pysz, K.; Siudak, R.; Szczurek, A.; Kupsc, A.; Pszczel, D.; Mikirtychiants, M.; Pyszniak, A.; Roy, A.; Sawant, S.; Serdyuk, V.; Sopov, V.; Yamamoto, A.; Yurev, L.; Zabierowski, J.

    2014-01-01

    We present new data for angular distributions and on the cross section ratio of the p+d → 3 He + η reaction at excess energies of Q = 48.8 MeV and Q = 59.8 MeV. The data have been obtained at the WASA-at-COSY experiment (Forschungszentrum Juelich) using a proton beam and a deuterium pellet target. While the shape of obtained angular distributions show only a slow variation with the energy, the new results indicate a distinct and unexpected total cross section fluctuation between Q = 20 MeV and Q = 60 MeV, which might indicate the variation of the production mechanism within this energy interval. (orig.)

  8. Project and supply agreement. The text of the agreement of 15 January 1993 between the International Atomic Energy Agency and the Government of the Republic of Indonesia and the Government of the United States of America concerning the transfer of enriched uranium for the fabrication of targets for the production of radioisotopes for medical purposes

    International Nuclear Information System (INIS)

    1994-08-01

    The text of the Project and Supply Agreement, which was approved by the Agency's Board of Governors on 4 December 1992 and concluded on 15 January 1993 between the Agency and the Governments of the Republic of Indonesia and the United States of America for the transfer of enriched uranium for the fabrication of targets for the production of radioisotopes for medical purposes is reproduced herein for the information of all Members. The agreement entered into force on 15 January 1993, pursuant to Article XII.1

  9. Availability of enrichment services

    International Nuclear Information System (INIS)

    Svenke, E.

    1977-01-01

    The report summarizes major uncertainties which are likely to influence future demands for uranium isotopic enrichment. Since for the next decade the development of nuclear power will be largely concerned with the increment in demand the timely need for enrichment capacity will be particularly sensitive to assumptions about growth rates. Existing worldwide capacity together with capacities under construction will be sufficient well into the 1980's. However, long decision and construction leadtime, uncertainty as to future demand as well as other factors, specifically high capital need, all of which entail financial risks, create hindrances to a timely development of increment. The adequacy of current technology is well demonstrated in plant operation and new technology is under way. Technology is, however, not freely available on a purely commercial basis. Commercial willingness, which anticipates a limited degree of financial risk, is requesting both long term back-up from the utilities that would parallel their firm decisions on the acquisition of nuclear power units, and a protective government umbrella. This situation depends on the symbiotic relationship that exists between the nuclear power generating organizations, the enrichment undertakings and the governments involved. The report accordingly stresses the need for a more cooperative approach and this, moreover, at the multinational level. There is otherwise a risk that proper resources and financing means will not be allocated to the enrichment sector. Export limitations that request the highest degree of industrial processing of nuclear fuel, i.e. the compulsory enrichment of natural uranium, do not serve the interests of overall industrial efficiency

  10. Promotion of uranium enrichment business

    International Nuclear Information System (INIS)

    Kurushima, Morihiro

    1981-01-01

    The Committee on Nuclear Power has studied on the basic nuclear power policy, establishing its five subcommittees, entrusted by the Ministry of Nternational Trade and Industry. The results of examination by the subcommittee on uranium enrichment business are given along with a report in this connection by the Committee. In order to establish the nuclear fuel cycle, the aspect of uranium enrichment is essential. The uranium enrichment by centrifugal process has proceeded steadily in Power Reactor and Nuclear Fuel Development Corporation. The following matters are described: the need for domestic uranium enrichment, the outlook for overseas enrichment services and the schedule for establishing domestic enrichment business, the current state of technology development, the position of the prototype enrichment plant, the course to be taken to establish enrichment business the main organization operating the prototype and commercial plants, the system of supplying centrifuges, the domestic conversion of natural uranium the subsidies for uranium enrichment business. (J.P.N.)

  11. United States uranium enrichment policies

    International Nuclear Information System (INIS)

    Roberts, R.W.

    1977-01-01

    ERDA's uranium enrichment program policies governing the manner in which ERDA's enrichment complex is being operated and expanded to meet customer requirements for separative work, research and development activities directed at providing technology alternatives for future enrichment capacity, and establishing the framework for additional domestic uranium enrichment capacity to meet the domestic and foreign nuclear industry's growing demand for enrichment services are considered. The ERDA enrichment complex consists of three gaseous diffusion plants located in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. Today, these plants provide uranium enrichment services for commercial nuclear power generation. These enrichment services are provided under contracts between the Government and the utility customers. ERDA's program involves a major pilot plant cascade, and pursues an advanced isotope separation technique for the late 1980's. That the United States must develop additional domestic uranium enrichment capacity is discussed

  12. Fusion with projectiles from carbon to argon at energies between 20A MeV and 60A MeV

    International Nuclear Information System (INIS)

    Galin, J.

    1986-01-01

    Fusion reactions are known to be the dominant reaction channel at low bombarding energies and can now be investigated with a large variety of projectiles at several tens of MeV per nucleon. The gross characteristics of the fusion process can be studied by measuring global quantities, such as the linear momentum transferred from projectile to target and the dissipated energy of the reaction. The strong correlation between these two quantities is demonstrated at moderate bombarding energies, with a Ne projectile on a U target. It is expected that light particle (charged or neutron) multiplicity measurements can be extended to this higher energy domain and be used to selectively filter these collisions, according to their degree of violence. A review of the linear momentum transfer is made, considering essentially heavy targets and two important parameters in the entrance channel: the projectile energy and its mass. Over a broad mass range, and for energies up to 30A MeV, the momentum transfer scales with the mass of the projectile. At 30A MeV, the most probable value of projectile momentum transferred to the fused system is 80%, and this represents roughly 180 MeV/c per projectile nucleon. At higher bombarding energies, the momentum distribution in the fused systems, as observed from binary fission events, seems to depend on the mass of the projectile. Further studies are still needed to understand this behavior. Finally, the decay of highly excited (E* similarly ordered 500-800 MeV) fused systems, with masses close to 270 amu, is studied from the characteristics of both fusion fragments and light charged particles. It is shown that thermal equilibrium is reached before fission, even for such high energy deposition. However, the decay sequence is sensitive to dynamical effects and does not depend only on available phase space

  13. Computational investigation of 99Mo, 89Sr, and 131I production rates in a subcritical UO2(NO32 aqueous solution reactor driven by a 30-MeV proton accelerator

    Directory of Open Access Journals (Sweden)

    Z. Gholamzadeh

    2015-12-01

    Full Text Available The use of subcritical aqueous homogenous reactors driven by accelerators presents an attractive alternative for producing 99Mo. In this method, the medical isotope production system itself is used to extract 99Mo or other radioisotopes so that there is no need to irradiate common targets. In addition, it can operate at much lower power compared to a traditional reactor to produce the same amount of 99Mo by irradiating targets. In this study, the neutronic performance and 99Mo, 89Sr, and 131I production capacity of a subcritical aqueous homogenous reactor fueled with low-enriched uranyl nitrate was evaluated using the MCNPX code. A proton accelerator with a maximum 30-MeV accelerating power was used to run the subcritical core. The computational results indicate a good potential for the modeled system to produce the radioisotopes under completely safe conditions because of the high negative reactivity coefficients of the modeled core. The results show that application of an optimized beam window material can increase the fission power of the aqueous nitrate fuel up to 80%. This accelerator-based procedure using low enriched uranium nitrate fuel to produce radioisotopes presents a potentially competitive alternative in comparison with the reactor-based or other accelerator-based methods. This system produces ∼1,500 Ci/wk (∼325 6-day Ci of 99Mo at the end of a cycle.

  14. Progress report on the 14-MeV fission cross section measurements

    International Nuclear Information System (INIS)

    1979-01-01

    The development of a recoil proton monitor was completed. It will be used to measure the neutron flux in the 14-MeV fisson cross section measurements. Extensive calculations of the efficiency of this monitor were made and compared with the calculations of other authors. It is clear that a major source of uncertainty in the efficiency is the lack of precise knowledge of the angular distribution of the n-p elastic scattering cross section. This leads to a change in efficiency of 3% depending on the form of the angular distribution that is used. A 4πβ-γ coincidence system was assembled to investigate the K-correction in determining the absolute activity of foil sources. Iron foils will be used as secondary flux standards in comparing the 14-MeV neutron flux with the fluxes in other laboratories, so this is an important correction to measure. The target and target holders that will be used in the 14-MeV measurements were designed and constructed. Preparations were completed to measure the angular distribution of the fission fragments produced in neutron-induced fission at 14 MeV. 2 figures

  15. Excitation functions of alpha particles induced nuclear reactions on natural titanium in the energy range of 10.4–50.2 MeV

    International Nuclear Information System (INIS)

    Usman, Ahmed Rufai; Khandaker, Mayeen Uddin; Haba, Hiromitsu; Otuka, Naohiko; Murakami, Masashi

    2017-01-01

    Highlights: • Detailed presentation of new results on experimental cross-sections of "n"a"tTi(α,x) processes. • Calculations of thick target yields for scandium and other radionuclides via the "n"a"tTi(α,x) production route. • Comparison with TENDL-2015 library. • Detailed review of previous experimental data. - Abstract: We studied the excitation functions of residual radionuclide productions from α particles bombardment on natural titanium in the energy range of 10.4–50.2 MeV. A well-established stacked-foil activation technique combined with HPGe γ-ray spectrometry was used to measure the excitation functions for the "5"1","4"9","4"8Cr, "4"8V, "4"3K, and "4"3","4"4"m","4"4"g","4"6"g"+"m","4"7","4"8Sc radionuclides. The thick target yields for all assessed radionuclides were also calculated. The obtained experimental data were compared with the earlier experimental ones and also with the evaluated data in the TENDL-2015 library. A reasonable agreement was found between this work and some of the previous ones, while a partial agreement was found with the evaluated data. The present results would further enrich the experimental database and facilitate the understanding of existing discrepancies among the previous measurements. The results would also help to enhance the prediction capability of the nuclear reaction model codes.

  16. Excitation functions of alpha particles induced nuclear reactions on natural titanium in the energy range of 10.4–50.2 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Usman, Ahmed Rufai [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Department of Physics, Umaru Musa Yar' adua University, Katsina (Nigeria); Khandaker, Mayeen Uddin, E-mail: mu_khandaker@um.edu.my [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Haba, Hiromitsu [Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Otuka, Naohiko [Nuclear Data Section, Division of Physical and Chemical Sciences, Department of Nuclear Sciences and Applications, International Atomic Energy Agency, A-1400 Vienna (Austria); Murakami, Masashi [Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan)

    2017-05-15

    Highlights: • Detailed presentation of new results on experimental cross-sections of {sup nat}Ti(α,x) processes. • Calculations of thick target yields for scandium and other radionuclides via the {sup nat}Ti(α,x) production route. • Comparison with TENDL-2015 library. • Detailed review of previous experimental data. - Abstract: We studied the excitation functions of residual radionuclide productions from α particles bombardment on natural titanium in the energy range of 10.4–50.2 MeV. A well-established stacked-foil activation technique combined with HPGe γ-ray spectrometry was used to measure the excitation functions for the {sup 51,49,48}Cr, {sup 48}V, {sup 43}K, and {sup 43,44m,44g,46g+m,47,48}Sc radionuclides. The thick target yields for all assessed radionuclides were also calculated. The obtained experimental data were compared with the earlier experimental ones and also with the evaluated data in the TENDL-2015 library. A reasonable agreement was found between this work and some of the previous ones, while a partial agreement was found with the evaluated data. The present results would further enrich the experimental database and facilitate the understanding of existing discrepancies among the previous measurements. The results would also help to enhance the prediction capability of the nuclear reaction model codes.

  17. Future of uranium enrichment

    International Nuclear Information System (INIS)

    Hosmer, C.

    1981-01-01

    The increasing amount of separative work being done in government facilities to produce low-enriched uranium fuel for nuclear utilities again raises the question: should this business-type, industrial function be burned over the private industry. The idea is being looked at by the Reagan administration, but faces problems of national security as well as from the unique nature of the business. This article suggests that a joint government-private venture combining enriching, reprocessing, and waste disposal could be the answer. Further, a separate entity using advanced laser technology to deplete existing uranium tails and lease them for fertile blankets in breeder reactors might earn substantial revenues to help reduce the national debt

  18. South Australia, uranium enrichment

    International Nuclear Information System (INIS)

    1976-02-01

    The Report sets out the salient data relating to the establishment of a uranium processing centre at Redcliff in South Australia. It is conceived as a major development project for the Commonwealth, the South Australian Government and Australian Industry comprising the refining and enrichment of uranium produced from Australian mines. Using the data currently available in respect of markets, demand, technology and possible financial return from overseas sales, the project could be initiated immediately with hexafluoride production, followed rapidly in stages by enrichment production using the centrifuge process. A conceptual development plan is presented, involving a growth pattern that would be closely synchronised with the mining and production of yellowcake. The proposed development is presented in the form of an eight-and-half-year programme. Costs in this Report are based on 1975 values, unless otherwise stated. (Author)

  19. Study of the gamma spectra emitted in a nuclear reaction - Measurement of the half-lives of the levels 6.13 MeV, 6.92 MeV and 7.12 MeV of 16O

    International Nuclear Information System (INIS)

    Leccia, F.

    1967-01-01

    When the energy shifts of the gamma spectrum released during a nuclear reaction are important compared with the detector resolution, the comparison of the experimental spectrum with theoretical spectra allows us to determine the half-life of the initial state of the transition. The calculation of the experimental spectrum implies to know the slowing-down of the recoil nucleus in the matter in order to take into account the Doppler effect. For recoil energies in the range of the MeV and for solid media, the Lindhard theory agrees well with experimental data. The phenomenon of deflection which appears at very low energies must be taken into account by restraining the measurement domain. By choosing an adequate media we can measure half-lives in the domain 1 and 100 fs without needing to take into account deflection effects. We have measured the half-life of the first 3 energy levels of 16 O (6.135 MeV, 6.923 MeV and 7.121 MeV), these levels are reached through the reaction 19 F(p,αγ) 16 O with proton incident energies ranging from 0.872 MeV to 2.42 MeV. We have used a coaxial germanium semi-conductor with lithium additions that was connected to an amplification line of Ortec type. 2 kinds of target have been used: calcium fluoride and copper fluoride evaporated on tantalum support. We have obtained the following values for the half-life: (16±4) fs for the 6.923 MeV level, (18±4) fs for the 7.121 MeV level, and for the 6.135 MeV we can only give a lower limit since the gamma decay occurs when the nucleus is at rest τ > 200 fs

  20. Study of the /sup 12/N 2. 43 MeV level. [Differential cross sections; 44 MeV /sup 3/He; 52 MeV p

    Energy Technology Data Exchange (ETDEWEB)

    Cecil, F E; Shepard, J R; Sercely, R R; Peterson, R J [Colorado Univ., Boulder (USA). Nuclear Physics Lab.; King, N S.P. [California Univ., Davis (USA). Crocker Nuclear Lab.

    1976-10-11

    The differential cross sections have been measured for the reactions /sup 12/C(/sup 3/He, /sup 3/He')/sup 12/C(17.77 MeV 0/sup +/ T = 1) and /sup 12/C(/sup 3/He, t)/sup 12/N(2.43 MeV) at Esub(/sup 3/He) = 44 MeV. The similar shapes of the angular distributions and the relative magnitudes of the cross sections suggest that the /sup 12/N 2.43 MeV level is the 0/sup +/ T = 1 analog to the /sup 12/C 17.77 MeV level. The reaction /sup 14/N(p, t)/sup 12/N(2.43 MeV) at Esub(p) = 52 MeV is also studied. The strength with which this level is excited in this reaction is consistent with reasonable two-step calculations assuming the 2.43 MeV level to have Jsup(..pi..) = 0/sup +/.

  1. Excitation functions and yields for cyclotron production of radiorhenium via deuteron irradiation. {sup nat}W(d,xn){sup 181,182,(A+B),183,184(m+g),186g}Re nuclear reactions and tests on the production of {sup 186g}Re using enriched {sup 186}W

    Energy Technology Data Exchange (ETDEWEB)

    Manenti, Simone; Persico, Elisa; Bonardi, Mauro L.; Gini, Luigi; Groppi, Flavia [LASA, Univ. degli Studi di Milano, Segrate (Italy); INFN Milano (Italy); Abbas, Kamel; Holzwarth, Uwe; Simonelli, Federica [Institute for Health and Consumer Protection, IHCP, JRC-Ispra, Ispra (Italy)

    2014-10-01

    Excitation functions, thin- and thick-target yields for the {sup 181-186g}Re and {sup 187}W radionuclides were measured by the activation stacked-foil technique on natural tungsten foils for deuteron energies up to 18.0 MeV. These cross sections were validated by comparing the experimental results for thick-target yields with those calculated by integration of the thin-target yields. It was found that the maximum {sup 186g}Re content by irradiation of natural tungsten is about 55%, a higher value compared with the one found for proton beam, but not sufficient to use natural tungsten for medical purposes yet. Thus, in order to have a higher specific activity A{sub S} of {sup 186g}Re, the use of enriched {sup 186}W target is necessary. Therefore the irradiation of a thick target of enriched {sup 186}W by accelerated deuterons was studied and the results for the production of {sup 186g}Re were compared with those obtained from the irradiation of the same target by accelerated protons. It was found that the deuteron irradiation is preferable for three reasons: larger yield, less contamination by tantalum radioisotopes and smaller required amount of the target, which simplify the separation of the {sup 186g}Re from the target itself.

  2. Measurement of the distributions of internuclear separations in 3.0-MeV H2+ and 3.63-MeV HeH+ beams

    International Nuclear Information System (INIS)

    Kanter, E.P.; Cooney, P.J.; Gemmell, D.S.; Vager, Z.; Pietsch, W.J.; Zabransky, B.J.

    1979-01-01

    Angular distributions of charged dissociation fragments are measured for 3.0-MeV H 2 + and 3.63-MeV HeH + ions incident on approx. 160 A carbon targets. By using the reflection method for a pure Coulomb potential, there are unfolded from these data the distributions of internuclear separations for each molecular-ion species prior to dissociation. These results are insensitive to ion-source conditions. For H 2 + this distribution, while approx. 2 times wider than a pure ground vibrational state population, is markedly different from the Franck-Condon distribution that has been previously assumed by other authors with similar rf and duo-plasmatron ion sources. For HeH + the distribution is slightly broader (approx. 1.5 times) than that expected for a pure ground state population. From the data, the initial vibrational state population in the incident beam can be extracted. 11 references

  3. Measurements and Monte Carlo calculations of neutron production cross-sections at 180o for the 140 MeV proton incident reactions on carbon, iron, and gold

    International Nuclear Information System (INIS)

    Iwamoto, Yosuke; Satoh, Daiki; Hagiwara, Masayuki; Yashima, Hiroshi; Nakane, Yoshihiro; Tamii, Atsushi; Iwase, Hiroshi; Endo, Akira; Nakashima, Hiroshi; Sakamoto, Yukio; Hatanaka, Kichiji; Niita, Koji

    2010-01-01

    The neutron production cross-sections of carbon, iron, and gold targets with 140 MeV protons at 180 o were measured at the RCNP cyclotron facility. The time-of-flight technique was used to obtain the neutron energy spectra in the energy range above 1 MeV. The carbon and iron target results were compared with the experimental data from 113 MeV (p,xn) reactions at 150 o reported by Meier et al. Our data agreed well with them in spite of different incident energies and angles. Calculations were then performed using different intra-nuclear cascade models (Bertini, ISOBAR, and JQMD) implemented with PHITS code. The results calculated using the ISOBAR and JQMD models roughly agreed with the experimental iron and gold target data, but the Bertini could not reproduce the high-energy neutrons above 10 MeV.

  4. 400 MeV upgrade for the Fermilab linac

    International Nuclear Information System (INIS)

    MacLachlan, J.A.

    1989-01-01

    Fermilab has plans for a comprehensive accelerator upgrade to open new possibilities for both the fixed target and collider experimental programs. An early step in this program is to increase the energy of the linac from 200 to 400 MeV by replacing the last four of its nine 201 MHz Alvarez tanks with twenty-eight 805 MHz side-coupled cavity chains operating at about 8 MV/m average axial field. The principal purpose is to reduce the incoherent spacecharge tuneshift at injection into the Booster which currently limits both the brightness of the beam, an important determinant of collider luminosity, and total intensity to produce both the antiprotons for the collider and the beams to fixed target experimental areas. Other consequences of higher Booster injection energy expected to contribute to some degree of higher intensity limits and improved operational characteristics include improved quality of the guide field at injection, reduced frequency swing for the rf systems, and smaller emittance for the injected beam. The linac upgrade project has moved from a 1986 study through a development project including structure models and numerical studies to a full-feature module prototyping starting this year

  5. Neutron induced alpha production from carbon between 18 and 22 MeV

    International Nuclear Information System (INIS)

    Stevens, A.P.

    1976-10-01

    Cross sections for neutron induced alpha production in carbon were measured at seventeen energies between 18 and 22 MeV, using a deuterated anthracene crystal as both target and detector. Pulse shape discrimination was employed to separate the alphas and elastically scattered deuterons from the other reaction products. Published (n,d) elastic scattering data were used as a standard to obtain the alpha production cross sections. Comparison with available measurements shows good agreement

  6. Fission cross section of 235U from 1 to 6 MeV

    International Nuclear Information System (INIS)

    Barton, D.M.; Diven, B.C.; Hansen, G.E.; Jarvis, G.A.; Koontz, P.G.; Smith, R.K.

    1976-01-01

    The ratio of the neutron-induced fission cross section of 235 U to the neutron-proton scattering cross section was measured in the neutron energy region from 1 to 6 MeV. The neutron source was the T(p,n) reaction produced by a pulsed Van de Graaff proton beam on a thin tritium gas target. The use of monoenergetic neutrons allowed time-of-flight methods to be used to study carefully backgrounds and source characteristics

  7. Pion production in 3He-nucleus interactions at 910 MeV

    International Nuclear Information System (INIS)

    Aslanides, E.; Baumann, P.; Bergdolt, G.; Engelstein, P.; Fassnacht, P.; Hibou, F.; Bressani, T.; Puddu, G.A.

    1983-01-01

    The ( 3 He, πsup(+-)X) reaction has been studied at 910 MeV using the 3 He ++ beam of the CERN SC, Complete π - spectra on CH 2 , CD 2 , 9 Be, 12 C, 27 Al, Cd and Pb, and π + spectra on CH 2 , CD 2 and 12 C targets have been measured at 0 0 , up or close to the kinematic limit xsub(F)=1. The results are compared to various theoretical calculations. (orig.)

  8. (p,3He) reactions on 1p shell nuclei at 41 and 45 MeV

    International Nuclear Information System (INIS)

    Rapp, V.

    1982-01-01

    In the present thesis the (p, 3 He) reactions on target nuclei of the 1p shell were studied. The measurements were performed at the isochronous cyclotron of the KFA Juelich. Angular distribution at 41 and 45 MeV to residual nuclear states in 7 Li, 8 Be, 9 Be, 10 B, 11 B, 12 C, 13 C, and 14 N. were evaluated. (orig.) [de

  9. Transport calculations for a 14.8 MeV neutron beam in a water phantom

    International Nuclear Information System (INIS)

    Goetsch, S.J.

    1981-01-01

    A coupled neutron/photon Monte Carlo radiation transport code (MORSE-CG) has been used to calculate neutron and photon doses in a water phantom irradiated by 14.8 MeV neutrons from the Gas Target Neutron Source. The source-collimator-phantom geometry was carefully simulated. Results of calculations utilizing two different statistical estimators (next-collision and track-length) are presented

  10. rvec p + 13 rvec C elastic scattering at 500 MeV

    International Nuclear Information System (INIS)

    Tanaka, N.

    1990-01-01

    For the first time, an elastic scattering experiment was performed at LAMPF using polarized protons and a polarized target nucleus (rvec p + 13 rvec C). The analyzing powers [A ooon (Θ)] and [A oonn (Θ)] were measured using an incident beam energy of 500 MeV over the laboratory angular range of 10 degree--30 degree. Motivation for the experiment and some preliminary results and conclusions are presented. 12 refs., 7 figs

  11. Feasibility of nondestructive assay measurements in uranium enrichment plants

    Energy Technology Data Exchange (ETDEWEB)

    Walton, R.B.

    1978-04-01

    Applications of nondestructive assay methods to measurement problems in uranium enrichment facilities are reviewed. The results of a number of test and evaluation projects that were performed over the last decade at ORGDP and Portsmouth are presented. Measurements of the residual holdup in the top enrichment portion of the shut-down K-25 cascade were made with portable neutron and gamma-ray detectors, and inventory estimates based on these data were in good agreement with ORGDP estimates. In the operating cascade, the tests showed that portable NaI detectors are effective for monitoring NaF and alumina media for gaseous effluent traps and that gas phase enrichments and inventories, as well as large deposits of uranium, can be detected with portable neutron and gamma-ray instrumentation. A wide variety of scrap and waste materials, including barrier and compressor blades, incinerator ash and trapping media, and miscellaneous waste, were measured using passive gamma-ray and neutron methods and 14-MeV neutron interrogation. Methods developed for rapid verification of UF/sub 6/ in shipping containers with portable neutron and gamma-ray instruments are now used routinely by safeguards inspectors. Passive assay methods can also be used to measure continuously the enrichments of /sup 235/U and /sup 234/U in the UF/sub 6/ product and tails withdrawals of a gaseous diffusion plant. A system that was developed and installed in the extended-range product withdrawal station of the Portsmouth facility measures enrichment with a relative accuracy of 0.5%. A stand-alone neutron detector has also been successfully evaluated for the measurement of the isotopic abundance of /sup 234/U in UF/sub 6/ in sample cylinders, an application of potential importance to Minor Isotope Safeguards Technology. Recommendations are made on the role of NDA measurements for enrichment plant safeguards, including additional tests and evaluations that may be needed, particularly for advanced uranium

  12. Beta activity of enriched uranium

    International Nuclear Information System (INIS)

    Nambiar, P.P.V.J.; Ramachandran, V.

    1975-01-01

    Use of enriched uranium as reactor fuel necessitates its handling in various forms. For purposes of planning and organising radiation protection measures in enriched uranium handling facilities, it is necessary to have a basic knowledge of the radiation status of enriched uranium systems. The theoretical variations in beta activity and energy with U 235 enrichment are presented. Depletion is considered separately. Beta activity build up is also studied for two specific enrichments, in respect of which experimental values for specific alpha activity are available. (author)

  13. A simple and powerful XY-Type current monitor for 30 MeV IPEN/CNEN-SP cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Barcellos, Henrique; Matsuda, Hylton; Sumyia, Luiz Carlos do A.; Junqueira, Fernando de C.; Costa, Osvaldo L. da, E-mail: hbolivei@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-11-01

    A water-cooled XY-type current monitor was designed and built in the Cyclotrons Laboratory of the Nuclear and Energy Research Institute (IPEN). It is a very simple design and easily adaptable to the cyclotron beam lines. Tests were done demonstrating to be an instrument of great assistance in proton beam position along beam transport line and target port. Nowadays the XY-type current monitor has been widely used in {sup 18}F-FDG routine productions, employing irradiation system which were originally designed for productions on 18 MeV cyclotron accelerator only, however, applying the XY-type current monitor the target port may be exchanged between the 30 MeV and 18 MeV cyclotrons and the observed results are in perfect agreement with expected. (author)

  14. Characterization of 2 MeV, 4 MeV, 6 MeV and 18 MeV buildup caps for use with a 0.6 cubic centimeter thimble ionization chamber

    International Nuclear Information System (INIS)

    Salyer, R.L.; VanDenburg, J.W.; Prinja, A.K.; Kirby, T.; Busch, R.; Hong-Nian Jow

    1996-07-01

    The purpose of this research is to characterize existing 2 MeV, 4 MeV and 6 MeV buildup caps, and to determine if a buildup cap can be made for the 0.6 cm 3 thimble ionization chamber that will accurately measure exposures in a high-energy photon radiation field. Two different radiation transport codes were used to computationally characterize existing 2 MeV, 4 MeV, and 6 MeV buildup caps for a 0.6 cm 3 active volume thimble ionization chamber: ITS, The Integrated TIGER Series of Coupled Electron-Photon Monte Carlo Transport Codes; and CEPXS/ONEDANT, A One-Dimensional Coupled Electron-Photon Discrete Ordinates Code Package. These codes were also used to determine the design characteristics of a buildup cap for use in the 18 MeV photon beam produced by the 14 TW pulsed power HERMES-III electron accelerator. The maximum range of the secondary electron, the depth at which maximum dose occurs, and the point where dose and collision kerma are equal have been determined to establish the validity of electronic equilibrium. The ionization chamber with the appropriate buildup cap was then subjected to a 4 MeV and a 6 MeV bremmstrahlung radiation spectrum to determine the detector response

  15. 14 MeV neutrons physics and applications

    CERN Document Server

    Valkovic, Vladivoj

    2015-01-01

    Despite the often difficult and time-consuming effort of performing experiments with fast (14 MeV) neutrons, these neutrons can offer special insight into nucleus and other materials because of the absence of charge. 14 MeV Neutrons: Physics and Applications explores fast neutrons in basic science and applications to problems in medicine, the environment, and security.Drawing on his more than 50 years of experience working with 14 MeV neutrons, the author focuses on:Sources of 14 MeV neutrons, including laboratory size accelerators, small and sealed tube generators, well logging sealed tube ac

  16. Review of neutron data: 10 to 40 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Haight, R.C.

    1977-04-01

    Neutron data are reviewed for incident neutron energies between 10 and 40 MeV. A census of the data shows that there are many gaps in this range and that the existing data are primarily for neutron energies around 14 MeV. Aside from total cross sections, there are few data between 10 and 13 MeV and between 15 and 40 MeV. Examples are presented to show the quality of selected data for total, elastic, inelastic, activation, and charged-particle and gamma-ray production cross sections. The spectra of emitted particles are also discussed.

  17. Review of neutron data: 10 to 40 MeV

    International Nuclear Information System (INIS)

    Haight, R.C.

    1977-04-01

    Neutron data are reviewed for incident neutron energies between 10 and 40 MeV. A census of the data shows that there are many gaps in this range and that the existing data are primarily for neutron energies around 14 MeV. Aside from total cross sections, there are few data between 10 and 13 MeV and between 15 and 40 MeV. Examples are presented to show the quality of selected data for total, elastic, inelastic, activation, and charged-particle and gamma-ray production cross sections. The spectra of emitted particles are also discussed

  18. Uranium enrichment by gas centrifuge

    International Nuclear Information System (INIS)

    Heriot, I.D.

    1988-01-01

    After recalling the physical principles and the techniques of centrifuge enrichment the report describes the centrifuge enrichment programmes of the various countries concerned and compares this technology with other enrichment technologies like gaseous diffusion, laser, aerodynamic devices and chemical processes. The centrifuge enrichment process is said to be able to replace with advantage the existing enrichment facilities in the short and medium term. Future prospects of the process are also described, like recycled uranium enrichment and economic improvements; research and development needs to achieve the economic prospects are also indicated. Finally the report takes note of the positive aspect of centrifuge enrichment as far as safeguards and nuclear safety are concerned. 27 figs, 113 refs

  19. Radiometric enrichment of nonradioactive ores

    International Nuclear Information System (INIS)

    Mokrousov, V.A.; Lileev, V.A.

    1979-01-01

    Considered are the methods of mineral enrichment based on the use of the radioation of various types. The physical essence of enrichment processes is presented, their classification is given. Described are the ore properties influencing the efficiency of radiometric enrichment, methods of the properties study and estimation of ore enrichment. New possibilities opened by radiometric enrichment in the technology of primary processing of mineral raw materials are elucidated. A considerable attention is paid to the main and auxiliary equipment for radiometric enrichment. The foundations of the safety engineering are presented in a brief form. Presented are also results of investigations and practical works in the field of enrichment of ores of non-ferrous, ferrous and non-metallic minerals with the help of radiometric methods

  20. Measurement of (n,Xn) reaction cross sections at 96 MeV

    International Nuclear Information System (INIS)

    Sagrado Garcia, Melle Inmaculada C.

    2006-10-01

    Nucleon induced reactions in the 20-200 MeV energy range are intensively studied since a long time. The evaporation and the pre-equilibrium processes correspond to an important contribution of the production cross section in these reactions. Several theoretical approaches have been proposed and their predictions must be tested. The experimental results shown in this work are the only complete set of data for the (n,Xn) reactions in this energy range. Neutron double differential cross section measurements using lead and iron targets for an incident neutron beam at 96 MeV were carried out at TSL Laboratory in Uppsala, Sweden. The measurements have been performed for the first time with an energy threshold of 2 MeV and for a wide angular range (15 angle - 98 angle). Neutrons have been detected using two independent setups, DECOI and DEMON and CLODIA and SCANDAL, in order to cover the whole energy range (2-100) MeV. The angular distributions, the differential cross sections and the total inelastic production cross sections have been calculated using the double differential cross sections. The comparison between the experimental data and the predictions given by two of the most popular simulation codes, GEANT3 and MCNPX, have been performed, as well as the comparison with the predictions of the microscopic simulation model DYWAN, selected for its treatment of nucleon-nucleon reactions. (author)

  1. Effects of repulsive three-body force in 12C + 12C scattering at 100A MeV

    Directory of Open Access Journals (Sweden)

    W.W. Qu

    2015-12-01

    Full Text Available The angular distribution of 12C + 12C scattering at an incident energy of 100A MeV has been measured. The elastic and inelastic scatterings in 12C to the excitation energies of up to ∼45 MeV were measured simultaneously for the first time with the high-resolution Grand Raiden spectrometer at the Research Center for Nuclear Physics (RCNP. The angular distributions of the elastic scattering to the ground state (01+ and inelastic scattering to the 4.44 MeV (21+ excited state were precisely obtained in the angular range of 1.0°–7.5° with a step of 0.1°. Additionally, the angular distribution was obtained for the sum of the cross sections for excitation energies above the 4.44 MeV state up to 11 MeV, which includes the 7.65 MeV (02+, 9.64 MeV (31−, and 10.30 MeV (22+ states, in addition to probably the simultaneous excitation of the 4.44 MeV state in the projectile and the target nuclei. Those combined data provide a means to study the effects of channel coupling on the elastic cross section. The observed angular distributions are compared with theoretical calculations based on three double-folding models with complex G-matrix interactions, the CEG07b, MPa, and ESC models. The importance of three-body repulsive forces included in the CEG07b and MPa models will be discussed.

  2. The world enrichment market

    International Nuclear Information System (INIS)

    Gunter, L.; McCants, C.; Rutkowski, E.

    1991-01-01

    The enrichment market can be divided into two periods: the near-term market (1991 to 1995) and the long-term market (1995 and beyond). The near-term market is characterized by limited unfilled requirements of 4% per year, to be supplied by national stockpiles and excess inventories. This low-cost material will be drawn down by about 1993, causing a subsequent price rise. As the price rises, primary supplier activity is expected to increase. In the near-term, two contracting activities are apparent: spot; and intermediate-term. The current spot market is expected to last until available low cost inventories are drawn down. Recently, in attempts to gain market share, suppliers have offered attractively priced intermediate-term (3 year) contracts for 1996 to 1998. While a small spot market will continue after 1995, it is anticipated that utilities will prefer a mix of medium- and long-term (5 to 10 year) contracts from primary suppliers for most of their enrichment requirements. As national stockpiles and utility inventories are consumed, low-cost supply available to the spot market is expected to diminish. Consequently, with little low-cost supply available, the only apparent source of material will be from primary suppliers, and the resulting competition over market share is expected to be intense. (author)

  3. Active interrogation of highly enriched uranium

    Science.gov (United States)

    Fairrow, Nannette Lea

    Safeguarding special nuclear material (SNM) in the Department of Energy Complex is vital to the national security of the United States. Active and passive nondestructive assays are used to confirm the presence of SNM in various configurations ranging from waste to nuclear weapons. Confirmation measurements for nuclear weapons are more challenging because the design complicates the detection of a distinct signal for highly enriched uranium. The emphasis of this dissertation was to investigate a new nondestructive assay technique that provides an independent and distinct signal to confirm the presence of highly enriched uranium (HEU). Once completed and tested this assay method could be applied to confirmation measurements of nuclear weapons. The new system uses a 14-MeV neutron source for interrogation and records the arrival time of neutrons between the pulses with a high efficiency detection system. The data is then analyzed by the Feynman reduced variance method. The analysis determined the amount of correlation in the data and provided a unique signature of correlated fission neutrons. Measurements of HEU spheres were conducted at Los Alamos with the new system. Then, Monte Carlo calculations were performed to verify hypothesis made about the behavior of the neutrons in the experiment. Comparisons of calculated counting rates by the Monte Carlo N-Particle Transport Code (MCNP) were made with the experimental data to confirm that the measured response reflected the desired behavior of neutron interactions in the highly enriched uranium. In addition, MCNP calculations of the delayed neutron build-up were compared with the measured data. Based on the results obtained from this dissertation, this measurement method has the potential to be expanded to include mass determinations of highly enriched uranium. Although many safeguards techniques exist for measuring special nuclear material, the number of assays that can be used to confirm HEU in shielded systems is

  4. Experimental cross section evaluation for innovative 99Mo production via the (α,n) reaction on 96Zr target

    International Nuclear Information System (INIS)

    Pupillo, Gaia; Gambaccini, M.; Esposito, J.; Haddad, F.; Michel, N.

    2014-01-01

    The recent crisis of 99 Mo production by nuclear reactors caused an unexpected worldwide 99m Tc shortening, forcing the international scientific community to find alternative production routes for these vital nuclides. One of the possibilities is to replace the current reactor-based method with the accelerator-based one. The aim of this work is the experimental evaluation of the 96 Zr(α,n) 99 Mo reaction, using the well known stacked foil technique with natural Zr targets, in the energy range 33-8 MeV. The results were compared with the published experimental values, finding good agreement in the trend of the cross section but at higher peak value. The results refer to 100% enriched 96 Zr target. The cross section values measured in the different irradiations show excellent agreement and indicate that the ideal energy range for 99 Mo production is 13-25 MeV. In comparison with the literature, there is good agreement in the trend of the cross section but at higher peak value. The 96 Zr(α,n) 99 Mo reaction is an interesting alternative production route of 99 Mo aimed at the realization of 99 Mo/ 99 mTc generators. Using enriched 96 Zr as target, 99 Mo is the only radioactive Mo-isotope produced, while using natural Zr as target, the resulting 99 Mo still has an high radioisotopic purity (only the radioactive 93 Mo is co-produced), but a lower specific activity. In both cases no Tc-nuclides are directly produced in target and the high purity 99m Tc results only from the decay of 99 Mo

  5. Modular enrichment measurement system for in-situ enrichment assay

    International Nuclear Information System (INIS)

    Stewart, J.P.

    1976-01-01

    A modular enrichment measurement system has been designed and is in operation within General Electric's Nuclear Fuel Fabrication Facility for the in-situ enrichment assay of uranium-bearing materials in process containers. This enrichment assay system, which is based on the ''enrichment meter'' concept, is an integral part of the site's enrichment control program and is used in the in-situ assay of the enrichment of uranium dioxide (UO 2 ) powder in process containers (five gallon pails). The assay system utilizes a commercially available modular counting system and a collimnator designed for compatability with process container transport lines and ease of operator access. The system has been upgraded to include a microprocessor-based controller to perform system operation functions and to provide data acquisition and processing functions. Standards have been fabricated and qualified for the enrichment assay of several types of uranium-bearing materials, including UO 2 powders. The assay system has performed in excess of 20,000 enrichment verification measurements annually and has significantly contributed to the facility's enrichment control program

  6. Development of 68Ge/68Ga Generator using 30 MeV Cyclotron

    International Nuclear Information System (INIS)

    Goo, Hur Min; Dae, Yang Seung; Hoon, Park Jeong; Dae, Park Yong; Je, Lee Eun; Bae, Kong Young; Kim, In Jong; Lee, Jin Woo; Hyun, Yu Kook

    2012-05-01

    The purpose of this research is to develop the 68 Ge/ 68 Ga generator where daughter nuclide 68 Ga can be eluted according to the designated periods from the resin which holds mother nuclide 68 Ge absorbed and to develop the 68 Ga utilization technology. 1. Target development for 68 Ge target and production of 68 Ge - Target designed for 68 Ge production with 30 MeV cyclotron - Target body material evaluation and proton beam irradiation 2. Separation of 68 Ge and development of column material and extraction system for 68 Ge/ 68 Ga separation - Development of 68 Ge separation method from nat Ga target - Development of absorbents for generator using stable isotope 3. Development of 68 Ga labelled radiopharmaceutical - Development of 68 Ga labelled benzamide derivative for diagnosis of melanoma - Development of 68 Ga dendrimer complex using nano-technology 4. Development of shield case for 68 Ge/ 68 Ga generator

  7. Excitation functions of 120Te(d,xn)121,120m,gI reactions from threshold up to 13.5 MeV: comparative studies on the production of 120gI

    International Nuclear Information System (INIS)

    Hohn, A.; Coenen, H.H.; Qaim, S.M.

    2000-01-01

    Excitation functions of the nuclear reactions 120 Te(d,xn) 121,120m,g I were measured for the first time from their respective thresholds up to 13.5 MeV. Thin samples prepared by electrolytic deposition of 99.0% enriched 120 Te on Ti-backing were used. Integral yields of 121,120m,g I were calculated from the measured cross section data. A comparison of the 122 Te(p,3n)-, 120 Te(p,n)- and 120 Te(d,2n)-processes for the production of 120g I is given. The 120 Te(d,2n)-process is unsuitable for production purposes since the yield of 120g I is very low and the level of 121 I impurity very high. The choice lies either on the 122 Te(p,3n)- or the 120 Te(p,n)-reaction and is governed by the available proton energy and the financial resources for procuring the enriched target material

  8. NSRL 200 MeV linac beam energy stabilization system

    International Nuclear Information System (INIS)

    Huang Guirong; Pei Yuanji; Dong Sai

    2001-01-01

    By using the computer image processing technology and RF phase auto-shifting system, the ESS (Energy Stabilization System) was applied to 200 MeV Linac. the ESS adjusts beam energy automatically in a range of +-4 MeV. After adjustment beam energy stability is improved to +-6%

  9. Parity Nonconservation in Proton-water Scattering at 800 MeV

    Science.gov (United States)

    Nagle, D. E.; Bowman, J. D.; Carlini, R.; Mischke, R. E.; Frauenfelder, H.; Harper, R. W.; Yuan, V.; McDonald, A. B.; Talaga, R.

    1982-01-01

    A search has been made for parity nonconservation in the scattering of 800 MeV polarized protons from an unpolarized water target. The result is for the longitudinal asymmetry, A{sub L} = +(6.6 +- 3.2) x 10{sup -7}. Control runs with Pb, using a thickness which gave equivalent beam broadening from Coulomb multiple scattering, but a factor of ten less nuclear interactions than the water target, gave A{sub L} = -(0.5 +- 6.0) x 10{sup -7}.

  10. Calculation of nucleon production cross sections for 200 MeV deuterons

    International Nuclear Information System (INIS)

    Ridikas, D.; Mittig, W.

    1997-01-01

    The differential neutron and proton production cross sections have been investigated for 200 MeV incident deuterons on thin and thick 9 Be, 56 Fe and 238 U targets using the LAHET code system. The examples of the deuteron beam on different target materials are analysed to determine the differences of converting the energy of the beam into the nucleons produced. Both double differential, energy and angle integrated nuclear production cross sections are presented together with the average nucleon multiplicities per incident deuteron. (K.A.)

  11. Calculation of nucleon production cross sections for 200 MeV deuterons

    Energy Technology Data Exchange (ETDEWEB)

    Ridikas, D.; Mittig, W.

    1997-12-31

    The differential neutron and proton production cross sections have been investigated for 200 MeV incident deuterons on thin and thick {sup 9}Be, {sup 56}Fe and {sup 238}U targets using the LAHET code system. The examples of the deuteron beam on different target materials are analysed to determine the differences of converting the energy of the beam into the nucleons produced. Both double differential, energy and angle integrated nuclear production cross sections are presented together with the average nucleon multiplicities per incident deuteron. (K.A.). 31 refs.

  12. Buckwheat-enriched wheat bread: National market placement possibilities

    Directory of Open Access Journals (Sweden)

    Sakač Marijana B.

    2015-01-01

    Full Text Available Quality parameters and the possibility of successful placement of buckwheat-enriched wheat bread on the national market are presented in this paper. Analysis of the market position of buckwheat-enriched wheat bread includes demands, offer and competition. Elements that affect the overall retail price of buckwheat-enriched wheat bread are given in details, along with SWOT analysis and marketing plan including target market, market supply and product marketing mix. According to all performed analyses it could be concluded that this product should be positioned on the national market, especially for people with special needs and requirements.

  13. Possibility of obtaining enriched americium-242g by the elution of recoil atoms from zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Shafiev, A I; Vityutnev, V M; Ivanov, V M; Yakovlev, G N

    1974-12-31

    On the example of production the possibility of obtaining enriched actinide isotopes by the elution of recotl atoms with the use of a zeolite- americium-241 target was shown. The enrichment factor and the recoil atoms of / sup 242g/Am yield depend on preliminary target treatment and solution composition used for elution. (auth)

  14. Enrichment of boron 10

    International Nuclear Information System (INIS)

    Coutinho, C.M.M.; Rodrigues Filho, J.S.R.; Umeda, K.; Echternacht, M.V.

    1990-01-01

    A isotopic separation pilot plant with five ion exchange columns interconnected in series were designed and built in the IEN. The columns are charged with a strong anionic resin in its alkaline form. The boric acid solution is introduced in the separation columns until it reaches a absorbing zone length which is sufficient to obtain the desired boron-10 isotopic concentration. The boric acid absorbing zone movement is provided by the injection of a diluted hydrochloric acid solution, which replace the boric acid throughout the columns. The absorbing zone equilibrium length is proportional to its total length. The enriched boron-10 and the depleted boron are located in the final boundary and in the initial position of the absorbing zones, respectively. (author)

  15. Thermal breeder fuel enrichment zoning

    International Nuclear Information System (INIS)

    Capossela, H.J.; Dwyer, J.R.; Luce, R.G.; McCoy, D.F.; Merriman, F.C.

    1992-01-01

    A method and apparatus for improving the performance of a thermal breeder reactor having regions of higher than average moderator concentration are disclosed. The fuel modules of the reactor core contain at least two different types of fuel elements, a high enrichment fuel element and a low enrichment fuel element. The two types of fuel elements are arranged in the fuel module with the low enrichment fuel elements located between the high moderator regions and the high enrichment fuel elements. Preferably, shim rods made of a fertile material are provided in selective regions for controlling the reactivity of the reactor by movement of the shim rods into and out of the reactor core. The moderation of neutrons adjacent the high enrichment fuel elements is preferably minimized as by reducing the spacing of the high enrichment fuel elements and/or using a moderator having a reduced moderating effect. 1 figure

  16. Advanced Neutron Source enrichment study

    International Nuclear Information System (INIS)

    Bari, R.A.; Ludewig, H.; Weeks, J.R.

    1996-01-01

    A study has been performed of the impact on performance of using low-enriched uranium (20% 235 U) or medium-enriched uranium (35% 235 U) as an alternative fuel for the Advanced Neutron Source, which was initially designed to use uranium enriched to 93% 235 U. Higher fuel densities and larger volume cores were evaluated at the lower enrichments in terms of impact on neutron flux, safety, safeguards, technical feasibility, and cost. The feasibility of fabricating uranium silicide fuel at increasing material density was specifically addressed by a panel of international experts on research reactor fuels. The most viable alternative designs for the reactor at lower enrichments were identified and discussed. Several sensitivity analyses were performed to gain an understanding of the performance of the reactor at parametric values of power, fuel density, core volume, and enrichment that were interpolations between the boundary values imposed on the study or extrapolations from known technology

  17. Exclusive measurements of light fragment production at forward angles in Ne-Pb and Ne-NaF collisions at E/A=400 MeV and 800 MeV

    International Nuclear Information System (INIS)

    Bastid, N.; Alard, J.P.; Arnold, J.; Augerat, J.; Biagi, F.; Crouau, M.; Charmensat, P.; Dupieux, P.; Fraysse, L.; Marroncle, J.; Montarou, G.; Parizet, M.J.; Qassoud, D.; Rahmani, A.; Schimmerling, W.

    1990-01-01

    Emission of light fragments at small angles is studied in relativistic heavy ion collisions using the Diogene plastic wall for both symmetrical and non-symmetrical target-projectile systems with 400 MeV per nucleon and 800 MeV per nucleon incident neon nuclei. Efficiency of multiplicity measurements in the small angle range for the selection of central or peripheral collisions is confirmed for asymmetric systems. Differential production cross sections of Z=1 fragments show evidence for the existence of two emitting sources. The apparent temperature of each source is obtained from comparison with a thermodynamical model. (orig.)

  18. Excitation functions of proton-induced reactions on {sup nat}Fe and enriched {sup 57}Fe with particular reference to the production of {sup 57}Co

    Energy Technology Data Exchange (ETDEWEB)

    Al-Abyad, M. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany); Cyclotron Facility, Nuclear Research Centre, Atomic Energy Authority, Cairo 13759 (Egypt); Comsan, M.N.H. [Cyclotron Facility, Nuclear Research Centre, Atomic Energy Authority, Cairo 13759 (Egypt); Qaim, S.M. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)], E-mail: s.m.qaim@fz-juelich.de

    2009-01-15

    Excitation functions of the reactions {sup nat}Fe(p,xn){sup 55,56,57,58}Co, {sup nat}Fe(p,x){sup 51}Cr, {sup nat}Fe(p,x){sup 54}Mn, {sup 57}Fe(p,n){sup 57}Co and {sup 57}Fe(p,{alpha}){sup 54}Mn were measured from their respective thresholds up to 18.5 MeV, with particular emphasis on data for the production of the radionuclide {sup 57}Co (T{sub 1/2}=271.8 d). The conventional stacked-foil technique was used, and the samples for irradiation were prepared by an electroplating or sedimentation process. The measured excitation curves were compared with the data available in the literature as well as with results of nuclear model calculations. From the experimental data, the theoretical yields of the investigated radionuclides were calculated as a function of the proton energy. Over the energy range E{sub p}=15{yields}5 MeV the calculated yield of {sup 57}Co from the {sup 57}Fe(p,n){sup 57}Co process amounts to 1.2 MBq/{mu}A h and from the {sup nat}Fe(p,xn){sup 57}Co reaction to 0.025 MBq/{mu}A h. The radionuclidic impurity levels are discussed. Use of highly enriched {sup 57}Fe as target material would lead to formation of high-purity {sup 57}Co.

  19. Neutrons leaked from a 45 MeV linac facility

    Energy Technology Data Exchange (ETDEWEB)

    Kitaichi, Masatoshi; Sawamura, Sadashi; Yamada, Takuma; Sawamura, Teruko; Kaneko, Junnichi H. [Hokkaido Univ., Sapporo (Japan); Nojiri, Itiro [Japan Nuclear Cycle Development Institute, Ibaraki (Japan)

    2002-07-01

    Dose evaluation for skyshine from nuclear facilities is an issue in environmental evaluations. Therefore, benchmark data for skyshine and well-investigated codes for skyshine would be useful in the rational evaluations of nuclear facilities. The purpose of this study is to obtain benchmark data of skyshine and to investigate the effect of source spectra and angular distribution on the skyshine process. In this study spatial and time distributions of neutrons leaked from the Hokkaido University 45 MeV electron linac facility were measured and compared with calculations. Neutrons were emitted from the ( ,n) reaction produced by bremsstrahlung radiation in a lead target irradiated with electrons from the linac. The skyshine process of neutrons transported through the facility building to the outside was investigated. The source spectrum of the skyshine process was evaluated using a cylindrical multi-moderator spectrometer and unfolding code, the SAND-II, and the results were compared. Measurements were carried out to a distance of 330 m from the facility. The measured spatial dose distribution was found not to coincide with the calculations. The discrepancy is discussed based on an analysis of the spatial and time distributions, and the energy spectrum which suggests that the source spectrum and the angular distribution assumed in the calculation was not sufficiently similar to simulate the experimental situation. The time distribution introduced in this study appears to be useful in discussions of the skyshine process and its sources.

  20. Electron beam fusion targets

    International Nuclear Information System (INIS)

    Clauser, M.J.; Sweeney, M.A.

    1975-01-01

    R The behavior of the DT filled gold shells when irradiated by a variety of pulse shapes was studied. In these pulses the power (and beam current) was varied, but the voltage was kept constant at 1 MeV. In general the performance of the target, for a given peak power, was not significantly affected by the pulse shape. Pulses with rise times of up to half the implosion time do not significantly degrade the target performance. The use of the ''optimal pulse'' of laser fusion with a fixed peak power does not appear to improve the performance of these targets. The main function of the ''optimal pulse'' is to produce a large rho r of the target during the thermonuclear burn. In e-beam targets a total rho r of 5--10 g/cm 2 can be obtained without pulse shaping; the problem here is one of achieving high enough temperatures to ignite the DT. (U.S.)

  1. Study of the neutron-proton interaction in the 300 to 700 MeV energy region. Annual progress report (1985-1986)

    International Nuclear Information System (INIS)

    Northcliffe, L.C.

    1986-01-01

    Results obtained for experiments conducted at the LAMPF are reported. All of these experiments utilize the LAMPF polarized (50%) neutron beam and hydrogen targets. Measurements are reported for spin-correlation parameters (500 to 800 MeV, 13 GeV/c, 18.5 GeV/c) and the analyzing power (800 MeV) for n-p elastic scattering. The status of earlier LAMPF experiments by this group are also included

  2. Enrichment plants. A survey of major new uranium enriching projects

    International Nuclear Information System (INIS)

    Kovan, D.

    1976-01-01

    The work enrichment situation is reported. The development of enrichment in the U.S. and in Europe is outlined. A brief description is given of the technology of separation by diffusion and by centrifugation and the advantages and disadvantages of the two processes are compared. Finally the supply and demand situation is briefly considered. (U.K.)

  3. Tests of health physics detectors and dosimeters to 6 and 9 MeV gamma-radiation

    International Nuclear Information System (INIS)

    1982-04-01

    The CEA health physicists working group on standardization and testing of detectors for the measurements of external exposure has set up and calibrated a capture #betta# beam. 6 and 9 MeV energies were obtained by means of Ti and Ni targets. These beams made it possible to determine the response of a number of detectors and dosimeters used in health physics to these energy ranges. Most generally, these tests showed that at 6 or 9 MeV the responses of instruments calibrated with 60 Co #betta#-rays could vary as much as a factor 2 when compared to the maximun of the absorbed dose in a human body [fr

  4. Confinement of 2,4 MeV deuterons by plasmoids and focalization of electron beams in plasma focus discharges

    International Nuclear Information System (INIS)

    Nardi, V.; Bostick, W.; Prior, W.; Feugeas, J.; Bortolotti, A.

    1982-01-01

    A detailed analysis has been completed on the internal structure of ions and electron beams which are efected, along the system axis, in opposite directions (0 0 and 180 0 ). An image (contact print) of plasmoids which emit MeV deuterons is formed by the deuteron emission and it is revealed by etching deuteron tracks in a target of plastic material (CR-39). Ion-imaging with different energy filters discriminates between tracks of plasmoid ions and tracks of charged products of D-D fusion reactions. Ions-imaging can also discriminate plasmoid deuterons from MeV deuterons of a directed beam. (L.C.) [pt

  5. The Energy Dependence of Flow in Ni Induced Collisions from 400A to 1970A MeV

    International Nuclear Information System (INIS)

    Chance, J.; Brady, F.; Cebra, D.; Kintner, J.; Partlan, M.; Romero, J.; Albergo, S.; Caccia, Z.; Costa, S.; Insolia, A.; Potenza, R.; Romanski, J.; Russo, G.; Tuve, C.; Bieser, F.; Cebra, D.; Lisa, M.; Matis, H.; McMahan, M.; McParland, C.; Olson, D.; Rai, G.; Rasmussen, J.; Ritter, H.; Symons, T.; Wieman, H.; Wienold, T.; Choi, Y.; Elliott, J.; Gilkes, M.; Hauger, J.; Hirsch, A.; Hjort, E.; Porile, N.; Scharenberg, R.; Srivastava, B.; Tincknell, M.; Warren, P.; Chacon, A.; Wolf, K.

    1997-01-01

    We study the energy dependence of collective (hydrodynamic-like) nuclear matter flow in (400 endash 1970)A MeV Ni+Au and (1000 endash 1970)A MeV Ni+Cu reactions. The flow increases with energy, appears to reach a maximum, and then to decrease at higher energies. A way of comparing the energy dependence of flow values for different projectile-target mass combinations is introduced, which demonstrates a more-or-less common scaling behavior among flow values from different systems. copyright 1997 The American Physical Society

  6. Cross section measurement of alpha particle induced nuclear reactions on natural cadmium up to 52 MeV

    OpenAIRE

    Ditrói, F.; Takács, S.; Haba, H.; Komori, Y.; Aikawa, M.

    2016-01-01

    Cross sections of alpha particle induced nuclear reactions have been measured on thin natural cadmium targets foils in the energy range from 11 to 51.2 MeV. This work was a part of our systematic study on excitation functions of light ion induced nuclear reactions on different target materials. Regarding the cross sections, the alpha induced reactions are not deeply enough investigated. Some of the produced isotopes are of medical interest, others have application in research and industry. Th...

  7. Low-temperature irradiation of niobium with 15-MeV neutrons

    International Nuclear Information System (INIS)

    Kerchner, H.R.; Coltman, R.R. Jr.; Klabunde, C.E.; Sekula, S.T.

    1978-01-01

    Niobium was irradiated at 4.2 K with high energy d-Be neutrons to a fluence of 3.7x10 15 n/cm 2 . The neutrons were generated at the Oak Ridge Isochronous Cyclotron by the breakup reaction of 40-MeV deuterons in a thick Be target. The resulting neutron energy spectrum was broadly peaked near 15 MeV. The 0.012-cm-diameter wire sample (RRR=200) was situated in a uniform transverse magnetic field. The critical current, flux flow resistance, and normal state resistance were measured by using a standard four-terminal technique. The critical current density and the flux flow resistivity were observed to increase with irradiation and to decrease toward the preirradiation values with subsequent isochronal annealing between 4.2 K and 360 K. Using recent theories of flux line lattice deformation, the elementary pinning force is deduced and the result is compared to theoretical calculations. (Auth.)

  8. Optimum design for 12 MeV linear induction accelerator diode

    International Nuclear Information System (INIS)

    Yu Haijun; Shi Jinshui; Li Qin; He Guorong; Ma Bing; Wang Jingsheng; Wang Liping

    2001-01-01

    A series of optimization designs of electron diode in 12 Mev linear induction accelerator are studied by using numerical simulation code MAGIC and experiment method in order to improve the electron beam quality. MAGIC code solves the Maxwell equations in the presence of charged particle, electron field distribution on cathode surface which influences electron emission is given, the optimum diode is obtained by comparing the results of experiment in 12 MeV linear induction accelerator. The author also gives SEM analysis and experiment comparison of velvet emission. Finally, emitted current I e = 8.52 kA, beam current I 8 ≥ 3.0 kA, targeted current I 0 ≥ 2.30 kA with optimum diode are obtained

  9. Sputtering of vanadium and niobium under 14.1 MeV neutron impact

    International Nuclear Information System (INIS)

    Kaminsky, M.; Das, S.K.

    1976-01-01

    The recent studies of particle emission from cold-rolled and annealed niobium under 14.1-MeV neutron impact were extended to a heavily etched, polycrystalline niobium surface and to cold worked vanadium surfaces with different degrees of microstructure. The type and amount of material released and deposited on collector surfaces facing the irradiated targets were determined by three analytical techniques. Two types of deposits were found for certain types of surfaces--one in the form of chunks; the other as a fractional atom layer covering the surface. The chunks vary significantly in size. The small number of chunks observed suggests that the ejection of chunks is a relatively rare event in comparison to the total number of primary knock-on events produced by 14-MeV neutrons in near surface regions. Estimates of the total sputtering yield based on the chunk deposits and on the fractional atom layer deposit will be given

  10. Cross sections from 800 MeV proton irradiation of terbium

    Energy Technology Data Exchange (ETDEWEB)

    Engle, J.W., E-mail: jwengle@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Mashnik, S.G.; Bach, H.; Couture, A.; Jackman, K.; Gritzo, R.; Ballard, B.D.; Fassbender, M.; Smith, D.M.; Bitteker, L.J.; Ullmann, J.L.; Gulley, M.S.; Pillai, C.; John, K.D.; Birnbaum, E.R. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Nortier, F.M., E-mail: meiring@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2012-11-02

    Terbium foils were irradiated with 800 MeV protons to ascertain the potential for production of lanthanide isotopes of interest in medical, astrophysical, and basic science research and to contribute to nuclear data repositories. Isotopes produced in the foil were quantified by gamma spectroscopy. Cross sections for 35 isotopes produced in the irradiation are reported and compared with predictions by the MCNP6 transport code using the CEM03.03, Bertini and INCL + ABLA event generators. Our results indicate the need to accurately consider fission and fragmentation of relatively light target nuclei like terbium in the modeling of nuclear reactions at 800 MeV. The predictive power of the code was found to be different for each event generator tested but was satisfactory for most of the product yields in the mass region where spallation reactions dominate. However, none of the event generators' results are in complete agreement with measured data.

  11. Development of low enriched uranium target plates by thermo-mechanical processing of UAl{sub 2}–Al matrix for production of {sup 99}Mo in Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Kanwar Liaqat; Khan, Akhlaque Ahmad [Pakistan Institute of Nuclear Science and Technology (PINSTECH) P.O Nilore, Islamabad (Pakistan); Mushtaq, Ahmad, E-mail: amushtaq1@hotmail.com [Pakistan Institute of Nuclear Science and Technology (PINSTECH) P.O Nilore, Islamabad (Pakistan); Imtiaz, Farhan; Ziai, Maratab Ali; Gulzar, Amir; Farooq, Muhammad; Hussain, Nazar; Ahmed, Nisar; Pervez, Shahid; Zaidi, Jamshed Hussain [Pakistan Institute of Nuclear Science and Technology (PINSTECH) P.O Nilore, Islamabad (Pakistan)

    2013-02-15

    Uranium aluminide predominated with UAl{sub 2} phase was prepared by arc-melting procedures and comminuted to required particle size. UAl{sub 2} and Al powders were blended and compacted to achieve LEU fuel density of 2.17 g/cm{sup 3}. The picture-frame technique was used to clad the dispersions (UAl{sub 2}–Al) with aluminum. A few target plates were fabricated by thermo-mechanical processing (hot rolling and annealing) of UAl{sub 2}–Al matrix contained in roll billet of Al. The fabricated plates were characterized by destructive and some of non-destructive testing techniques and then annealed to achieve required phase of uranium aluminide for proper dissolution in basic media.

  12. Industrial aspects in uranium enrichment

    International Nuclear Information System (INIS)

    Mezin, M.

    1982-05-01

    Characteristics of isotope separation processes in operation and under development are discussed. These include the number of stages in series, the number of components, the component unit capacity and enery requirements. The implementation of an enrichment process and the question of an enrichment plant in Australia are also considered

  13. City model enrichment

    Science.gov (United States)

    Smart, Philip D.; Quinn, Jonathan A.; Jones, Christopher B.

    The combination of mobile communication technology with location and orientation aware digital cameras has introduced increasing interest in the exploitation of 3D city models for applications such as augmented reality and automated image captioning. The effectiveness of such applications is, at present, severely limited by the often poor quality of semantic annotation of the 3D models. In this paper, we show how freely available sources of georeferenced Web 2.0 information can be used for automated enrichment of 3D city models. Point referenced names of prominent buildings and landmarks mined from Wikipedia articles and from the OpenStreetMaps digital map and Geonames gazetteer have been matched to the 2D ground plan geometry of a 3D city model. In order to address the ambiguities that arise in the associations between these sources and the city model, we present procedures to merge potentially related buildings and implement fuzzy matching between reference points and building polygons. An experimental evaluation demonstrates the effectiveness of the presented methods.

  14. Challenges in designing a very compact 130 MeV Moeller polarimeter for the S-DALINAC

    Energy Technology Data Exchange (ETDEWEB)

    Bahlo, Thore; Enders, Joachim; Kuerzeder, Thorsten; Pietralla, Norbert; Wissmann, Jan [Institut fuer Kernphysik, TU Darmstadt, Darmstadt (Germany)

    2016-07-01

    The Superconducting Darmstadt Linear Accelerator is capable of accelerating polarized electron beams produced by the S-DALINAC Polarized Injector (SPIN). For electron energies of up to 14 MeV it is possible to measure the absolute polarization of the electrons with two Mott polarimeters that are already mounted in the injector beamline. Until now it is not possible to measure the absolute electron beam polarization after the passage of the main accelerator. Therefore a Moeller polarimeter for energies between 50 MeV and 130 MeV is currently being developed. The rather low incident beam energy, the variability of the incident beam energy, and spatial restrictions necessitate a compact set-up with large acceptance. The very restrictive boundary conditions introduce technical and geometrical challenges. We will present the design of the target chamber, of the separation dipole magnet as well as the beam dump.

  15. Polarized triton scattering from 26Mg, 27Al and 28Si at 17 MeV

    International Nuclear Information System (INIS)

    Hardekopf, R.A.; Brown, R.E.; Correll, F.D.; Ohlsen, G.G.

    1980-01-01

    Differential-cross-section and analyzing-power angular distributions were measured for 17 MeV tritons elastically scattered from targets of 26 Mg, 27 Al, and 28 Si in the angular range 20 to 160 0 . The experiment was performed at the Los Alamos Scientific Laboratory Van de Graaff facility using the Lamb-shift polarized triton source and the supercube scattering chamber. A pair of detector telescopes with angular resolutions of +-0.4 0 detected the reaction products, with mass identification and storage performed by an on-line computer. The triton beam intensity available at the target was about 70 nA with a polarization of 0.77. The target thicknesses were about 3 mg/cm 2 , although thinner targets were used for the 27 Al forward-angle data

  16. Experimental investigation of saturation depth of 0.662 MeV gamma rays in copper

    International Nuclear Information System (INIS)

    Singh, Gurvinderjit; Singh, Manpreet; Sandhu, B.S.; Singh, Bhajan

    2007-01-01

    The effect of target thickness on 0.662 MeV multiply Compton scattered gamma photon has been studied experimentally. An intense collimated beam, obtained from 6-Ci 137 Cs source, is allowed to impinge on a rectangular copper target of varying thickness and the scattered photons are detected by a properly shielded NaI(TI) scintillation detector, having dimensions 51 φ mm x 5l mm, placed at 90 deg to the incident beam. The subtraction of events under the analytically reconstructed full energy peak from the events recorded under the observed inelastic peak results in multiply scattered events having energy same as in single scattering. The target thickness at which the number of multiply scattered events saturates has also been determined. The signal-to-noise ratio is found to be decreasing with increasing target thickness. Monte Carlo calculation supports the present experimental results. (author)

  17. AEC determines uranium enrichment policy

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The Advisory Committee on Uranium Enrichment of the Atomic Energy Commission (AEC) has submitted a report to AEC chairman concerning the promotion of the introduction of advanced material, high performance centrifuges to replace conventional metallic drum centrifuges, and the development of next generation advanced centrifuges. The report also called for the postponement until around 1997 of the decision whether the development should be continued or not on atomic vapor laser isotope separation (AVLIS) and molecular laser isotope separation (MLIS) processes, as well as the virtual freezing of the construction of a chemical process demonstration plant. The report was approved by the AEC chairman in August. The uranium enrichment service market in the world will continue to be characterized by oversupply. The domestic situation of uranium enrichment supply-demand trend, progress of the expansion of Rokkasho enrichment plant, the trend in the development of gas centrifuge process and the basic philosophy of commercializing domestic uranium enrichment are reported. (K.I.)

  18. New generation enrichment monitoring technology for gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Ianakiev, Kiril D.; Alexandrov, Boian S.; Boyer, Brian D.; Hill, Thomas R.; Macarthur, Duncan W.; Marks, Thomas; Moss, Calvin E.; Sheppard, Gregory A.; Swinhoe, Martyn T.

    2008-01-01

    The continuous enrichment monitor, developed and fielded in the 1990s by the International Atomic Energy Agency, provided a go-no-go capability to distinguish between UF 6 containing low enriched (approximately 4% 235 U) and highly enriched (above 20% 235 U) uranium. This instrument used the 22-keV line from a 109 Cd source as a transmission source to achieve a high sensitivity to the UF 6 gas absorption. The 1.27-yr half-life required that the source be periodically replaced and the instrument recalibrated. The instrument's functionality and accuracy were limited by the fact that measured gas density and gas pressure were treated as confidential facility information. The modern safeguarding of a gas centrifuge enrichment plant producing low-enriched UF 6 product aims toward a more quantitative flow and enrichment monitoring concept that sets new standards for accuracy stability, and confidence. An instrument must be accurate enough to detect the diversion of a significant quantity of material, have virtually zero false alarms, and protect the operator's proprietary process information. We discuss a new concept for advanced gas enrichment assay measurement technology. This design concept eliminates the need for the periodic replacement of a radioactive source as well as the need for maintenance by experts. Some initial experimental results will be presented.

  19. Hydrogen-enriched fuels

    Energy Technology Data Exchange (ETDEWEB)

    Roser, R. [NRG Technologies, Inc., Reno, NV (United States)

    1998-08-01

    NRG Technologies, Inc. is attempting to develop hardware and infrastructure that will allow mixtures of hydrogen and conventional fuels to become viable alternatives to conventional fuels alone. This commercialization can be successful if the authors are able to achieve exhaust emission levels of less than 0.03 g/kw-hr NOx and CO; and 0.15 g/kw-hr NMHC at full engine power without the use of exhaust catalysts. The major barriers to achieving these goals are that the lean burn regimes required to meet exhaust emissions goals reduce engine output substantially and tend to exhibit higher-than-normal total hydrocarbon emissions. Also, hydrogen addition to conventional fuels increases fuel cost, and reduces both vehicle range and engine output power. Maintaining low emissions during transient driving cycles has not been demonstrated. A three year test plan has been developed to perform the investigations into the issues described above. During this initial year of funding research has progressed in the following areas: (a) a cost effective single-cylinder research platform was constructed; (b) exhaust gas speciation was performed to characterize the nature of hydrocarbon emissions from hydrogen-enriched natural gas fuels; (c) three H{sub 2}/CH{sub 4} fuel compositions were analyzed using spark timing and equivalence ratio sweeping procedures and finally; (d) a full size pick-up truck platform was converted to run on HCNG fuels. The testing performed in year one of the three year plan represents a baseline from which to assess options for overcoming the stated barriers to success.

  20. Scattering of 130 MeV helions on 58Ni

    International Nuclear Information System (INIS)

    Djaloeis, A.; Alderliesten, C.; Bojowald, J.; Oelert, W.; Turek, P.

    1982-01-01

    Angular distributions for the tau + 58 Ni scattering to the (g.s., 0 + ) (1.45 MeV, 2 + ) and giant resonance (Esub(x) approximately 63Asup(-1/3) MeV) states in 58 Ni have been measured at Esub(tau) = 130 MeV in an angular range thetasub(c.m.) = 6 0 -83 0 . Optical model and DWBA analyses have been performed. The use of helion optical potentials with either a volume (Woods-Saxon) or a surface (Woods-Saxon derivative) absorption results in good fits to the g.s. and 1.45 MeV data. However, the volume absorption gives consistently a better fit quality. The discrete ambiguity of the helion optical potential has been resolved in favour of the shallow potential family. The giant resonance is found to have a dominant quadrupole (L=2) character with about 6% (EWSR) L=4 admixture. (Auth.)

  1. Performances of large BGO crystals below 20 MeV

    International Nuclear Information System (INIS)

    Burq, J.P.; Chemarin, M.; El Mamouni, H.

    1986-11-01

    This paper presents the performances of large tapered BGO crystals to low energy photons of 6 to 20 MeV. The read-out of the crystals was made with large area photodiodes associated to shaping amplifiers

  2. High enrichment to low enrichment core's conversion. Technical securities

    International Nuclear Information System (INIS)

    Abbate, P.; Madariaga, M.R.

    1990-01-01

    This work presents the fulfillment of the technical securities subscribed by INVAP S.E. for the conversion of a high enriched uranium core. The reactor (of 5 thermal Mw), built in the 50's and 60's, is of the 'swimming pool' type, with light water and fuel elements of the curve plates MTR type, enriched at 93.15 %. These are neutronic and thermohydraulic securities. (Author) [es

  3. Safety of uranium enrichment plant

    International Nuclear Information System (INIS)

    Yonekawa, Shigeru; Morikami, Yoshio; Morita, Minoru; Takahashi, Tsukasa; Tokuyasu, Takashi.

    1991-01-01

    With respect to safety evaluation of the gas centrifuge enrichment facility, several characteristic problems are described as follows. Criticality safety in the cascade equipments can be obtained to maintain the enrichment of UF 6 below 5 %. External radiation dose equivalent rate of the 30B cylinder is low enough, the shield is not necessary. Penetration ratio of the two-stage HEPA filters for UF 6 aerosol is estimated at 10 -9 . From the experimental investigation, vacuum tightness is not damaged by destruction of gas centrifuge rotor. Carbon steel can be used for uranium enrichment equipments under the condition below 100degC. (author)

  4. Environmental enrichment for aquatic animals.

    Science.gov (United States)

    Corcoran, Mike

    2015-05-01

    Aquatic animals are the most popular pets in the United States based on the number of owned pets. They are popular display animals and are increasingly used in research settings. Enrichment of captive animals is an important element of zoo and laboratory medicine. The importance of enrichment for aquatic animals has been slower in implementation. For a long time, there was debate over whether or not fish were able to experience pain or form long-term memories. As that debate has reduced and the consciousness of more aquatic animals is accepted, the need to discuss enrichment for these animals has increased. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. World enrichment requirements to 2005

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The primary enrichment suppliers-Eurodif, Techsnabexport, Urenco, and the US DOE - are positioning themselves to take advantage of the post - 1995 market. Overall, unfilled requirements represent about 40 percent of world requirements in the year 2000. The USA will be the primary market, as US utilities' unfilled enrichment requirements account for over 60 percent of the world's total unfilled requirements. The enrichment market is moving toward more global competition, as each supplier tries to maintain its current regional market base and then to capture additional market share in other regions

  6. Measurement of cross sections for the scattering of neutrons in the energy range from 2 MeV to 4 MeV with the 15N(p,n) reaction as neutron source

    International Nuclear Information System (INIS)

    Poenitz, Erik

    2010-01-01

    In future nuclear facilities, the materials lead and bismuth can play a more important role than in today's nuclear reactors. Reliable cross section data are required for the design of those facilities. In particular the neutron transport in the lead spallation target of an Accelerator-Driven Subcritical Reactor strongly depends on the inelastic neutron scattering cross sections in the energy region from 0.5 MeV to 6 MeV. In the recent 20 years, elastic and inelastic neutron scattering cross sections were measured with high precision for a variety of elements at the PTB time-of-flight spectrometer. The D(d,n) reaction was primarily used for the production of neutrons. Because of the Q value of the reaction and the available deuteron energies, neutrons in the energy range from 6 MeV to 16 MeV can be produced. For the cross section measurement at lower energies, however, another neutron producing reaction is required. The 15 N(p,n) 15 O reaction was chosen, as it allows the production of monoenergetic neutrons with up to 5.7MeV energy. In this work, the 15 N(p,n) reaction was studied with focus on the suitability as a source for monoenergetic neutrons in scattering experiments. This includes the measurement of differential cross sections for the neutron producing reaction and the choice of optimum target conditions. Differential elastic and inelastic neutron scattering cross sections were measured for lead at four energies in the region from 2 MeV to 4 MeV incident neutron energy using the time-of-flight technique. A lead sample with natural isotopic composition was used. NE213 liquid scintillation detectors with well-known detection efficiencies were used for the detection of the scattered neutrons. Angle-integrated cross sections were determined by a Legendre polynomial expansion using least-squares methods. Additionally, measurements were carried out for isotopically pure 209 Bi and 181 Ta samples at 4 MeV incident neutron energy. Results are compared with other

  7. A novel source of MeV positron bunches driven by energetic protons for PAS application

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Zongquan, E-mail: tqq1123@mail.ustc.edu.cn [State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Xu, Wenzhen; Liu, Yanfen; Xiao, Ran; Kong, Wei [State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Ye, Bangjiao, E-mail: bjye@ustc.edu.cn [State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-11-01

    This paper proposes a novel methodology of MeV positrons generation for PAS application. Feasibility of this proposal analyzed by G4Beamline and Transport have shown reasonable success. Using 2 Hz, 1.6 GeV, 100 ns and 1.5 μC/bunch proton bunches for bombarding a graphite target, about 100 ns e{sup +} bunches are generated. Quasi-monochromatic positrons in the range of 1–10 MeV included in these bunches have a flux of >10{sup 7}/s, peak brightness of 10{sup 14}/s. A magnetic-confinement beamline is utilized to transport the positrons and a “Fast Beam Chopper” is unprecedentedly extended to chop those relativistic bunches. The positron beam can be finally characterized by the energy range of 1–10 MeV and bunch width from one hundred ps up to 1 ns. Such ultrashort bunches can be useful in tomography-type positron annihilation spectroscopy (PAS) as well as other applications.

  8. A novel source of MeV positron bunches driven by energetic protons for PAS application

    Science.gov (United States)

    Tan, Zongquan; Xu, Wenzhen; Liu, Yanfen; Xiao, Ran; Kong, Wei; Ye, Bangjiao

    2014-11-01

    This paper proposes a novel methodology of MeV positrons generation for PAS application. Feasibility of this proposal analyzed by G4Beamline and Transport have shown reasonable success. Using 2 Hz, 1.6 GeV, 100 ns and 1.5 μC/bunch proton bunches for bombarding a graphite target, about 100 ns e+ bunches are generated. Quasi-monochromatic positrons in the range of 1-10 MeV included in these bunches have a flux of >107/s, peak brightness of 1014/s. A magnetic-confinement beamline is utilized to transport the positrons and a "Fast Beam Chopper" is unprecedentedly extended to chop those relativistic bunches. The positron beam can be finally characterized by the energy range of 1-10 MeV and bunch width from one hundred ps up to 1 ns. Such ultrashort bunches can be useful in tomography-type positron annihilation spectroscopy (PAS) as well as other applications.

  9. Generation and application of 15 to 30 MeV parametric X-ray by linac

    CERN Document Server

    Akimoto, T

    2002-01-01

    15 to 30 MeV parametric X-ray (PXR) was generated using Si single crystal by 45 MeV electron LINAC. To obtain good monochromatic hard X-ray field, the appropriate conditions were determined by theoretical analysis and experiments. The intensity of PXR was increased with increasing electron energy and crystal rotation angle. However, PXR energy is independent of electron energy. By increasing measurement angle, energy of PXR decreased, but its intensity increased. 15 to 30 keV PXR energy and about 10 sup - sup 5 to 10 sup - sup 6 photon/electron of intensity were observed at 15 to 22 deg detection angle under the operation conditions of 45 MeV electron energy and 4 to 8 nA of beam current. The mass attenuation coefficient of photon of Zr, Nb and Mo, in K absorption edge was measured. Application to determine lattice distortion of target sample and off-angle of crystal was investigated. Generation and detection of PXR, measurement of characteristic properties: crystal rotation angle, detection angle, electron e...

  10. Evaluation of induced radioactivity in 10 MeV electron-irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Katayama, Tadashi; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1993-10-01

    In order to make clear appreciation to induced radioactivity in the irradiated foods, photonuclear reactions which could produce radioactivity at energies up to 10 MeV were listed up from elemental compositions of black pepper, white pepper, red pepper, ginger and turmeric. The samples were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy and radioactivity was measured. Induced radioactivity could not be detected significantly by gamma-ray spectrometry and beta-ray counting in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H[sub 50] according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from [sup 40]K contained in the samples. (J.P.N.).

  11. A 14-MeV beam-plasma neutron source for materials testing

    International Nuclear Information System (INIS)

    Futch, A.H.; Coensgen, F.H.; Damm, C.C.; Molvik, A.W.

    1989-01-01

    The design and performance of 14-MeV beam-plasma neutron sources for accelerated testing of fusion reactor materials are described. Continuous production of 14-MeV neutron fluxes in the range of 5 to 10 MW/m 2 at the plasma surface are produced by D-T reactions in a two-component plasma. In the present designs, 14-MeV neutrons result from collisions of energetic deuterium ions created by transverse injection of 150-keV deuterium atoms on a fully ionized tritium target plasma. The beam energy, which deposited at the center of the tritium column, is transferred to the warm plasma by electron drag, which flows axially to the end regions. Neutral gas at high pressure absorbs the energy in the tritium plasma and transfers the heat to the walls of the vacuum vessel. The plasma parameters of the neutron source, in dimensionless units, have been achieved in the 2XIIB high-β plasma. The larger magnetic field of the present design permits scaling to the higher energy and density of the neutron source design. In the extrapolation, care has been taken to preserve the scaling and plasma attributes that contributed to equilibrium, magnetohydrodynamic (MHD) stability, and microstability in 2XIIB. The performance and scaling characteristics are described for several designs chosen to enhance the thermal isolation of the two-component plasmas. 11 refs., 3 figs., 3 tabs

  12. Photoneutron source based on a compact 10 MeV betatron

    International Nuclear Information System (INIS)

    Chakhlov, V.L.; Bell, Z.W.; Golovkov, V.M.; Shtein, M.M.

    1999-01-01

    Accelerator-based photoneutron sources have enjoyed wide use and offer the advantages of long term stability, ease of control and absence of radioactive materials. We report here measurements of the yield of photoneutrons from a neutron generator using a compact betatron. Electrons were accelerated to energies up to 10 MeV and produced a bremsstrahlung beam with a dose rate of 0.16 Gy/min (at 10 MeV, 1 m from the bremsstrahlung target) to irradiate LiD, Be, depleted U, and Pb neutron-producing targets. The angular distributions of photoneutrons produced by bremsstrahlung beams were measured with a 'long' counter and integrated to determine neutron yield. In addition, neutron time of flight spectra were recorded from all targets using a 15.5 m flight path perpendicular to the photon beam. The maximum observed yields were 4.6x10 7 n/s obtained with 1 kg of LiD, 5.7x10 7 n/s from a 3.3 kg Be block, 6.2x10 6 n/s from 1.5 kg of depleted U, and 7.0x10 6 n/s from 10.7 kg of Pb. Optimization of target dimensions, shape, and positioning is expected to increase the yield from the LiD target by a factor of 35, while optimization of the other targets is expected to yield at most a factor of 10. With the increased yield and a deuteride target, this compact betatron-based system could find application in the interrogation of waste containers for fissile material

  13. Search for a resonant structure in inclusive Cu (p,ππ+O) reactions between 300 and 400 MeV

    International Nuclear Information System (INIS)

    Julien, J.

    1989-01-01

    The results of the inclusive reactions Cu (p,π + )X and Cu (p,π O )X, carried out in the Saturne accelerator facility and using a pion detector, are discussed. Experiments with carbon targets were also performed. The variation of the ratio (R) between lower and higher energy pion yields are analyzed and show that the width of the structure is about 5 MeV for copper. No enhancement is observed at 350 MeV for carbon. In the neutral pion experiment, the R value is roughly constant for forward direction, except at 355 and 360 MeV. The results do not allow to conclude about the existence of a narrow structure around the proton incident energy of 350 MeV

  14. Centar's gas centrifuge enrichment project

    International Nuclear Information System (INIS)

    Abajian, V.V.; Fishman, A.M.

    1976-01-01

    Plans for the building and operating of Centar Associates gas centrifuge uranium enrichment plant are described. Operating costs and machine manufacture are considered. Commitments with the utilities are summarised. (U.K.)

  15. Extraosseus enrichments in bone scintigraphy

    International Nuclear Information System (INIS)

    Jochens, R.; Schumacher, T.; Amthauer, H.; Wolter, M.; Stock, W.; Stroszczynski, C.; Moersler, J.P.; Eichstaedt, H.

    1996-01-01

    Extraosseus enrichments are common findings in bone scintigraphy. Main causes are artifacts by skin or cloth contamination, paravenous and subcutaneous injection. Physical examination, removal of cloths, skin cleaning or further images in differing projections lead to the correct diagnosis artefact or extraosseous enrichments. Further on, extraosseous enrichments are seen in physiological variants. In different diseases extraosseous enrichments are common, especially in urinary tract, liver and extremities. Further diagnostics, e.g. conventional radiologic procedures, sonography and CT scans, have to be performed. In individual cases side results in bone scintigraphy lead to formerly unknown diagnosis, further diagnostic procedure is influenced decisively. Own cases show for example a cerebral apoplectic insult, formerly unknown liver metastasis or metastasis in extraosseous Ewings's sarcoma. (orig.) [de

  16. Use of 13.5-MeV neutrons for protein determination in grain crops

    International Nuclear Information System (INIS)

    Barit, I.A.; Kuz'min, L.E.; Makarov, S.A.; Vozhzhov, V.F.; Pronman, I.M.

    1989-01-01

    One of the main objectives of the Food Supply Program, i.e., that of improving the quality of crop production, is bound up intimately with the intensification of work on the selection and genetics of high-protein grain and legume crops. High-protein stains cannot be isolated without the proper analytical service for mass testing of the nitrogen content in the grain, which is one of the main elements of protein. The neutron-activation method of nitrogen determination is based on the use of the 14 N(n, 2n) 13 N nuclear reaction (E th = 11.3 MeV) with an average neutron energy of ∼14.5 MeV. In this work the authors consider a new variant of the neutron-activation method of determining nitrogen in grain and legume crops. The method is based on the use of monoenergetic neutrons with an energy of ∼13.5 MeV, generated in relatively thin titanium-tritium targets by a mass-separated deuteron beam from neutron generators operating at 150-300 kV, in order to eliminate the interference of the reaction 39 K(n, 2n) 38 K (E thr = 13.4 MeV). The present method has been used to determine the protein content (mass %) in different grains and legumes at the All-Union Selection-Genetic Institute of the Lenin Academy of Agricultural Sciences. The correctness of the analysis was checked by comparison with the data of chemical analysis. The discrepancy between the results of the two methods does not exceed 3%, which is within the limits of the error of measurement of Δ and K s.r

  17. Radiography studies with gamma rays produced by 14-MeV fusion neutrons

    International Nuclear Information System (INIS)

    Smith, D.L.; Ikeda, Yujiro; Uno, Yoshitomo

    1996-01-01

    Oxygen contained in pure water has been activated via the 16 O(n, p) 16 N reaction using 14-MeV neutrons produced at a neutron generator with the 3 H(d,n) 4 He source. Photons of 6.129 and 7.115 MeV, generated by the decay of 7.13-second 16 N, were then used to demonstrate the feasibility of employing highly penetrating, nearly monoenergetic gamma rays for radiography studies of thick, dense objects composed of elements with medium to relatively high atomic numbers. A simple radiography apparatus was constructed by circulating water continuously between a position near the target of the neutron generator and a remote location where photon transmission measurements were conducted. A sodium iodide scintillator was employed to detect the photons. Pulses equivalent to photon energies smaller than 2.506 MeV (corresponding to the cascade sum of 1.333- and 1.173-MeV gamma rays from the decay of 5.271-year 60 Co) were rejected by the electronics settings in order to reduce background and improve the signal-to-noise (S/N) ratio. Respectable S/N ratios on the order of 20-to-1 were achieved with this setup. Most of the background (N) could be attributed to ambient environmental radiation and cosmic-ray interactions with the lead shielding and detector. Four representative objects were examined by photon radiography in this study. This demonstrated how such - interesting features as hidden holes and discontinuities in atomic number could be easily identified from observed variations in the intensity of transmitted photons. Some advantages of this technique are described, and potential applications are suggested for a future scenario where fusion reactors are used to generate electric power and very intense sources of high-energy photons from 16 N decay are continuously available as a byproduct of the reactor cooling process

  18. Measurement of neutron captured cross-sections in 1-2 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Gi Dong; Kim, Young Sek; Kim, Jun Kon; Yang, Tae Keun [Korea Institutes of Geoscience and Mineral Resources, Taejeon (Korea)

    2001-04-01

    The measurement of neutron captured reaction cross sections was performed to build the infra system for the production of nuclear data. MeV neutrons were produced with TiT target and {sup 3}T(p,n){sup 3}He reaction. The characteristics of TiT thin film was analyzed with ERD-TOF and RBS. The results was published at Journal of the Korea Physical Society (SCI registration). The energy, the energy spread and the flux of the produced neutron were measured. The neutron excitation functions of {sup 12}C and {sup 16}O were obtained to confirm the neutron energy and neutron energy spread. The neutron energy spread found to be 1.3 % at the neutron energy of 2.077 MeV. The {sup 197}Au(n,{gamma}) reaction was performed to obtain the nerutron flux. The maximum neutron flux found to be 1 x 10{sup 8} neutrons/sec at the neutron energy of 2 MeV. The absolute efficiency of liquid scintillation detector was obtained in the neutron energy of 1 - 2 MeV. The fast neutron total reaction cross sections of Cu, Fe, and Au were measured with sample in-out method. Also the neutron captured reaction cross sections of {sup 63}Cu were measured with fast neutron activation method. The measurement of neutron total reaction cross sections and the neutron captured reaction cross sections with fast neutrons were first tried in Korea. The beam pulsing system was investigated and the code of calculating the deposition spectrums for primary gamma rays was made to have little errors at nuclear data. 25 refs., 28 figs., 14 tabs. (Author)

  19. Measurement of cross sections for the scattering of neutrons in the energy range from 2 MeV to 4 MeV with the {sup 15}N(p,n) reaction as neutron source; Messung von Wirkungsquerschnitten fuer die Streuung von Neutronen im Energiebereich von 2 MeV bis 4 MeV mit der {sup 15}N(p,n)-Reaktion als Neutronenquelle

    Energy Technology Data Exchange (ETDEWEB)

    Poenitz, Erik

    2010-04-26

    In future nuclear facilities, the materials lead and bismuth can play a more important role than in today's nuclear reactors. Reliable cross section data are required for the design of those facilities. In particular the neutron transport in the lead spallation target of an Accelerator-Driven Subcritical Reactor strongly depends on the inelastic neutron scattering cross sections in the energy region from 0.5 MeV to 6 MeV. In the recent 20 years, elastic and inelastic neutron scattering cross sections were measured with high precision for a variety of elements at the PTB time-of-flight spectrometer. The D(d,n) reaction was primarily used for the production of neutrons. Because of the Q value of the reaction and the available deuteron energies, neutrons in the energy range from 6 MeV to 16 MeV can be produced. For the cross section measurement at lower energies, however, another neutron producing reaction is required. The {sup 15}N(p,n){sup 15}O reaction was chosen, as it allows the production of monoenergetic neutrons with up to 5.7MeV energy. In this work, the {sup 15}N(p,n) reaction was studied with focus on the suitability as a source for monoenergetic neutrons in scattering experiments. This includes the measurement of differential cross sections for the neutron producing reaction and the choice of optimum target conditions. Differential elastic and inelastic neutron scattering cross sections were measured for lead at four energies in the region from 2 MeV to 4 MeV incident neutron energy using the time-of-flight technique. A lead sample with natural isotopic composition was used. NE213 liquid scintillation detectors with well-known detection efficiencies were used for the detection of the scattered neutrons. Angle-integrated cross sections were determined by a Legendre polynomial expansion using least-squares methods. Additionally, measurements were carried out for isotopically pure {sup 209}Bi and {sup 181}Ta samples at 4 MeV incident neutron energy

  20. The reaction p12C→ηX from Tp=800 MeV to Tp=1500 MeV

    International Nuclear Information System (INIS)

    Chiavassa, E.; Dellacasa, G.; De Marco, N.; De Oliveira Martins, O.; Gallio, M.; Guaita, P.; Musso, A.; Piccotti, A.; Scomparin, E.; Vercellin, E.

    1998-01-01

    The reaction p 12 C→nX has been studied, at several proton kinetic energies ranging from 800 MeV to 1500 MeV, at the proton synchrotron Saturne at Saclay. The measured doubly differential cross-sections are presented and discussed in the framework of a simple theoretical model. The model fails in describing the deepest subthreshold data while the above-threshold data are fairly well reproduced. (orig.)

  1. Uranium enrichment: an evolving market

    International Nuclear Information System (INIS)

    Longenecker, J.; Witzel, R.

    1997-01-01

    With over half of the world uranium enrichment market uncommitted to any supplier early in the next century, competition is certain to be fierce. In the meantime the outlood remains unclear, with the market dominated by a number of developments -privatisation of the United States Enrichment Corp (USEC), increasing availability of Russian and US military inventories, the deployment of advanced technology and the closure of nuclear power plants due to deregulation. (author)

  2. Unjust enrichment in business law

    OpenAIRE

    Vydrová, Zuzana

    2016-01-01

    This thesis analyses the concept of unjust enrichment under the business law. First of all the thesis explains the term of business law. Business law is a complex of legal rules concerning the contractual relationships between entrepreneurs arising from their business activities. Business law is a comprehensive field of law which extends into many other fields of law, both private and public law. Equally the regulation of unjust enrichment within the business law expands into many other laws ...

  3. Activation of 45-MeV proton irradiation and proton-induced neutron irradiation in polymers

    International Nuclear Information System (INIS)

    Ra, Se-Jin; Kim, Kye-Ryung; Jung, Myung-Hwan; Yang, Tae-Keon

    2010-01-01

    During beam irradiation experiments with more than a few MeV energetic protons, the sample activation problem can be very severe because it causes many kinds of additional problems for the post-processing of the samples, such as time loss, inconvenience of sample handling, personal radiation safety, etc. The most serious problem is that immediate treatment of the sample is impossible in some experiments, such as nano-particle synthesizing. To solve these problems, we studied why the samples are activated and how the level of the activation can be reduced. It is known that the main reasons of activation are nuclear reactions with elements of the target material by primary protons and secondary produced neutrons. Even though the irradiation conditions are same, the level of the activation can be different depending on the target materials. For the nanoparticle synthesizing experiments, the target materials can be defined as the container and the sample itself. The reduction of the activation from the container is easier than the reduction from the sample. Therefore, we tried to reduce the activation level by changing the container materials. In this paper, the results are displayed for some candidate container materials, such as polymethyl methacrylate, polystyrene, Glass, etc., with 45-MeV and 10-nA proton beams. As a result, PS is the most suitable material for the container because of its relatively low level of the activation by protons. Also the contribution of secondary produced neutrons to the activation is negligible.

  4. GXRD study of 100 MeV Fe9+ ion irradiated indium phosphide

    International Nuclear Information System (INIS)

    Dubey, R.L.; Dubey, S.K.; Kachhap, N.K.; Kanjilal, D.

    2014-01-01

    Swift heavy ions with MeV to GeV kinetic energy offer unique possibilities of modifying material properties. Each projectile passing through the target material causes loss of its energy by ion-electrons and ion-atoms interaction with the target material. The consequence of formal one is to change in surface properties and latter to produces damage deep in the target material near the projected range of projectile. In the present work, indium phosphide samples were irradiated at 100 MeV 56 Fe 9+ ions with different fluences varying from 1x10 12 to 1x10 14 ions cm -2 using the 15UD Pelletron facilities at Inter University Accelerator Centre (IUAC), New Delhi. Grazing angle X-ray diffraction technique was used to investigate the structural properties of irradiated indium phosphide at different depths. The GXRD spectra of non-irradiated and irradiated samples were recorded at different grazing angle i.e 1°, 2°, 3°, 4° and 5° to get the structural information over the projected range. The detailed result will be presented and discussed in the conference. (author)

  5. Giessen polarization facility. II. 1. 2 MeV tandem accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, W; Ulbricht, J; Berg, H; Keiner, P; Krause, H H; Schmidt, R; Clausnitzer, G [Giessen Univ. (Germany, F.R.). Strahlenzentrum

    1977-06-15

    A small pressure insulated tandem accelerator with 600 kV terminal voltage was constructed for the application of a polarized ion source of the Lambshift type: thin carbon foils or gas stripping is used for the charge exchange in the high voltage terminal. The calculated ion optical properties were realized in the construction; transmission and energy resolution are sufficient to obtain high intensity polarized beams on target (maximum 0.6..mu..A protons with P=0.75 ) for precision polarization experiments in the 0.2-1.2 MeV energy region.

  6. Prediction of (n, 3He) cross sections around 14 MeV

    International Nuclear Information System (INIS)

    Atasoy, H.; Doekmen, S.

    1995-01-01

    A comprehensive review of the neutron-induced cross-reactions for (n, 3 He) reactions has been made for the interval of 14 ≤ Z ≤ 84 around 14 MeV neutron energy. For practical purposes, an empirical expression has been found by using the experimental (n, 3 He) cross section values as a function of (N - Z) and (E n - E th ) where (N - Z) is the neutron excess of the target nucleus, E n and E th are the incident neutron energy and the (n, 3 He) threshold energy, respectively. The derived empirical relation gives a good fit with the experimental values

  7. The investigation of deuteron production double differential cross section induced by 392 MeV protons

    International Nuclear Information System (INIS)

    Kin, Tadahiro; Nakano, Masahiro; Imamura, Minoru

    2006-01-01

    We have investigated the deuteron productions from 392 MeV proton induced reaction for target nuclei of 12 C, 27 Al, 93 Nb. Deuteron production double differential cross sections were determined over a broad energy range and scattered angles from 20 to 105 degrees in laboratory system. Those spectra were compared with two theoretical models; Quantum Molecular Dynamics model and Intranuclear Cascade model. We developed the code of Intra Nuclear Cascade model and we've got good results to reproduce the experimental data. (author)

  8. Radioprotection shielding for neutrons induced by the reaction (2H (40 MeV, 12C

    Directory of Open Access Journals (Sweden)

    Fadil M.

    2017-01-01

    Full Text Available In the framework of design studies for SPIRAL2, the simulation of the neutron flux generated by 40 MeV deuterons on a thick 12C target was performed and compared to experimental data. The calculation of the dose rate of these neutrons allowed to compare four materials being considered for radioprotection shielding: barites, gypsum, ordinary concrete and heavy concrete. The simulated map of the neutron dose rate in the production building shows a very high dose rate around the neutron source and in the environment of some of the accelerator equipment.

  9. Total K-vacancy production in Ne (10 MeV) traversing Al

    International Nuclear Information System (INIS)

    Groeneveld, K.O.; Kolb, B.; Schader, J.; Sevier, K.D.

    1976-01-01

    Deexcitation of projectile inner shell vacancies created while traversing a solid foil may take place via competing processes: a) vacancy sharing with foil atoms in close impacts, b) radiative and non-radiative electron capture, and c) such X-ray and Auger electron transitions are possible in the heavy ion projectile. The change in K-vacancy creation with foil thickness can be investigated by measuring either projectile or target X-rays where the vacancies are created by Coulomb excitation and process a. In the system Ne (10 MeV) on Al, detecting Al K X-rays, the Ne K-vacancy production probability has been determined. (orig.) [de

  10. Proton induced nuclear reactions on cadmium up 17 MeV

    International Nuclear Information System (INIS)

    Al-Abyad, M.

    2012-01-01

    The cross-sections of proton induced reactions on nat Cd targets was studied in the energy range from threshold up to 17 MeV, using a stacked-foil irradiation technique and classical gamma-spectroscopy. We measured the formation cross-sections of the radioisotopes 109g,110m,110,111g,113m,114m,115m,116m In The obtained excitation functions were compared with the earlier published data and the theoretical model calculations by the codes ALICE-IPPE, EMPIRE and TALYS .

  11. Gamma-ray-spectroscopy following high-flux 14-MeV neutron activation

    Energy Technology Data Exchange (ETDEWEB)

    Williams, R.E.

    1981-10-12

    The Rotating Target Neutron Source (RTNS-I), a high-intensity source of 14-MeV neutrons at the Lawrence Livermore National Laboratory (LLNL), has been used for applications in activation analysis, inertial-confinement-fusion diagnostic development, and fission decay-heat studies. The fast-neutron flux from the RTNS-I is at least 50 times the maximum fluxes available from typical neutron generators, making these applications possible. Facilities and procedures necessary for gamma-ray spectroscopy of samples irradiated at the RTNS-I were developed.

  12. Gamma-ray-spectroscopy following high-flux 14-MeV neutron activation

    International Nuclear Information System (INIS)

    Williams, R.E.

    1981-01-01

    The Rotating Target Neutron Source (RTNS-I), a high-intensity source of 14-MeV neutrons at the Lawrence Livermore National Laboratory (LLNL), has been used for applications in activation analysis, inertial-confinement-fusion diagnostic development, and fission decay-heat studies. The fast-neutron flux from the RTNS-I is at least 50 times the maximum fluxes available from typical neutron generators, making these applications possible. Facilities and procedures necessary for gamma-ray spectroscopy of samples irradiated at the RTNS-I were developed

  13. Empirical formulae for 14.5 MeV (n,p) cross sections

    International Nuclear Information System (INIS)

    Selvi, S.; Erbil, H.H.

    1989-12-01

    Six empirical formulae of the (n,p) cross sections for 14.5-MeV neutrons were obtained with respect to even and odd (N-Z) values, depending on the effective Q-Value, the Coulomb barrier height, the threshold and incident neutron energies and the mass number of the target. These formulae were compared with the experimental values. The present calculations fit the experimental results quite well compared to those predicted by the previous workers. (author). 8 refs, 1 fig., 1 tab

  14. Photodisintegration of 4He studied with TPC using 22-32 MeV real photons

    International Nuclear Information System (INIS)

    Shima, T.; Baba, T.; Kii, T.; Takahashi, T.; Naito, S.; Nagai, Y.; Ohgaki, H.; Toyokawa, H.

    2002-01-01

    The photodisintegration of 4 He at the γ-ray energy of about 25 MeV provides a useful tool to investigate the problems of the electromagnetic transition strength in the reaction and the charge symmetry in nuclear force. In this study we made a new exclusive measurement of the photodisintegration of 4 He using a laser-Compton-backscattered γ beam and a time projection chamber with an active target. The preliminary result indicates no anomalous violation of the charge symmetry and suppression of the transition strength compared to the expected one from the E1 sum rule. (author)

  15. Measurement of the angular distribution of neutron-proton scattering at 10 MeV

    International Nuclear Information System (INIS)

    Haight, R.C.; Bateman, F.B.; Grimes, S.M.; Brient, C.E.; Massey, T.N.; Wasson, O.A.; Carlson, A.D.; Zhou, H.

    1995-01-01

    The relative angular distribution of neutrons scattered from protons was measured at an incident neutron energy of 10 MeV at the Ohio University Accelerator Laboratory. An array of 11 detector telescopes at laboratory angles of 0 to 60 degrees was used to detect recoil protons from neutron interactions with a CH 2 (polypropylene) target. Data for 7 of these telescopes were obtained with one set of electronics and are presented here. These data, from 108 to 180 degrees for the center-of-mass scattering angles, have a small slope which agrees better with angular distributions predicted by the Arndt phase shifts than with the ENDF/B-VI angular distribution

  16. Two-body photodisintegration of 3He between 7 and 16 MeV

    International Nuclear Information System (INIS)

    Tornow, W.; Karwowski, H.J.; Kelley, J.H.; Raut, R.; Rusev, G.; Stave, S.C.; Tonchev, A.P.; Deltuva, A.; Fonseca, A.C.; Marcucci, L.E.; Viviani, M.; Kievsky, A.; Golak, J.; Skibinski, R.; Witala, H.; Schiavilla, R.

    2011-01-01

    A comprehensive data set is reported for the two-body photodisintegration cross section of 3 He using mono-energetic photon beams at eleven energies between 7.0 and 16.0 MeV. A 3 He+Xe high-pressure gas scintillator served as target and detector. Although our data are in much better agreement with our state-of-the-art theoretical calculations than the majority of the previous data, these calculations underpredict the new data by about 10%. This disagreement suggests an incomplete understanding of the dynamics of the three-nucleon system and its response to electromagnetic probes.

  17. Two-body photodisintegration of {sup 3}He between 7 and 16 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Tornow, W., E-mail: tornow@tunl.duke.edu [Duke University, Durham, NC 27708-0308 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Karwowski, H.J. [University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3255 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Kelley, J.H. [North Carolina State University, Raleigh, NC 27695-8202 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Raut, R.; Rusev, G.; Stave, S.C.; Tonchev, A.P. [Duke University, Durham, NC 27708-0308 (United States); Triangle Universities Nuclear Laboratory, Durham, NC 27708-0308 (United States); Deltuva, A.; Fonseca, A.C. [Centro de Fisica Nuclear da Universidade de Lisboa, P-1649-003 Lisboa (Portugal); Marcucci, L.E. [Department of Physics, ' Enrico Fermi' , University of Pisa, I-56127 Pisa (Italy); INFN, Sezione di Pisa, I-56100 Pisa (Italy); Viviani, M.; Kievsky, A. [INFN, Sezione di Pisa, I-56100 Pisa (Italy); Golak, J.; Skibinski, R.; Witala, H. [M. Smoluchowski Institute of Physics, Jagiellonian University, PL-30059 Krakow (Poland); Schiavilla, R. [Department of Physics, Old Dominion University, Norfolk, VA 23529 (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States)

    2011-08-11

    A comprehensive data set is reported for the two-body photodisintegration cross section of {sup 3}He using mono-energetic photon beams at eleven energies between 7.0 and 16.0 MeV. A {sup 3}He+Xe high-pressure gas scintillator served as target and detector. Although our data are in much better agreement with our state-of-the-art theoretical calculations than the majority of the previous data, these calculations underpredict the new data by about 10%. This disagreement suggests an incomplete understanding of the dynamics of the three-nucleon system and its response to electromagnetic probes.

  18. Phenomenological and microscopic optical potentials for 88 MeV 7Li scattering

    International Nuclear Information System (INIS)

    Steeden, M.F.; Coopersmith, J.; Cartwright, S.J.; Cohler, M.D.; Clarke, N.M.; Griffiths, R.J.

    1980-01-01

    The elastic scattering cross sections for 88 MeV 7 Li ions have been measured for targets of 24 26 Mg and 40 48 Ca. Analyses using both phenomenological and microscopic optical potentials provide information on the energy dependence of optical parameters, and the extent to which the potentials are determined for these light ions. The use of a double-folding microscopic model demonstrates the need for normalisation of the real potential by a factor of 0.5 in contrast to measurements at lower energies. The contribution of exchange effects, density dependence and break-up are discussed. (author)

  19. Energy loss of carbon transmitted 1-MeV H2+ ions

    International Nuclear Information System (INIS)

    Fritz, M.; Kimura, K.; Susuki, Y.; Mannami, M.

    1994-01-01

    Energy losses of 1-MeV H 2 + ions passing through carbon foils of 2-8 μg/cm 2 thickness have been measured and show besides the linear increase with target thickness a 0.4 keV offset. The stopping power derived from the observed energy losses is 1.15 times as large as the sum of the stopping powers for two single H + of the same velocity. Calculations of the stopping powers for H 2 + ions and diprotons, using first Born approximation, indicate that the H 2 + ions lose the binding electron upon entrance into the foil, traverse the target as diprotons and recapture target electrons at the exit surface, a scenario also supported by the 0.4 keV offset at zero thickness. (author)

  20. Efficient production and diagnostics of MeV proton beams from a cryogenic hydrogen ribbon

    International Nuclear Information System (INIS)

    Velyhan, A.; Giuffrida, L.; Scuderi, V.; Lastovicka, T.; Margarone, D.; Perin, J.P.; Chatain, D.; Garcia, S.; Bonnay, P.; Dostal, J.; Ullschmied, J.; Dudzak, R.; Krousky, E.; Cykhardt, J.; Prokupek, J.; Pfeifer, M.; Rosinski, M.; Krasa, J.; Brabcova, K.; Napoli, M. De

    2017-01-01

    A solid hydrogen thin ribbon, produced by the cryogenic system ELISE (Experiments on Laser Interaction with Solid hydrogEn) target delivery system, was experimentally used at the PALS kJ-laser facility to generate intense proton beams with energies in the MeV range. This sophisticated target system operating at cryogenic temperature (∼ 10 K) continuously producing a 62 μm thick target was combined with a 600 J sub-nanosecond laser pulse to generate a collimated proton stream. The accelerated proton beams were fully characterized by a number of diagnostics. High conversion efficiency of laser to energetic protons is of great interest for future potential applications in non-conventional proton therapy and fast ignition for inertial confinement fusion.

  1. Basic Research and Feasibility Study of Radioisotope Production using 100 MeV Proton Beam

    International Nuclear Information System (INIS)

    Yoo, K. H.; Yoon, K. S.; Cho, W. J.; Park, S. I.; Han, H. S.; Yang, S. D.; Jeon, K. S.; Kim, J. H.; Yang, T. K.

    2010-04-01

    Results of the project are various nuclei, such as 82 Rb, 68 Ga, 67 Cu, 22 Na and so on, can be produced by irradiating 100 MeV proton beam, by irradiating proton beam to the nat Ga target, the 68 Ge, mother nucleus of positron emitting 68 Ga, is produced based on the nat Ga(p,x) 68 Ge reaction, the target system for the high-energy of proton beam can produce more than 2 species of radioisotope at the same time by employing tandem targets, 68 Ge/ 68 Ga generator, 82 Sr(25.34d)/ 82 Rb generator - 67 Cu production method, 70 Zn electroplating technology based on the electrochemistry, the container, whose weight is about 3 ton, is made by depleted uranium and because of the unstable situation for the supply and demand of reactor produced radioisotope, the need for the cyclotron produced radioisotopes is dramatically increased all over the world.

  2. Electron and ion currents relevant to accurate current integration in MeV ion backscattering spectrometry

    International Nuclear Information System (INIS)

    Matteson, S.; Nicolet, M.A.

    1979-01-01

    The magnitude and characteristics of the currents which flow in the target and the chamber of an MeV ion backscattering spectrometer are examined. Measured energy distributions and the magnitude of high-energy secondary electron currents are reported. An empirical universal curve is shown to fit the energy distribution of secondary electrons for several combinations of ion energy, targets and ion species. The magnitude of tertiary electron currents which arise at the vacuum vessel walls is determined for various experimental situations and is shown to be non-negligible in many cases. An experimental arrangement is described which permits charge integrations to 1% arruracy without restricting access to the target as a Faraday cage does. (Auth.)

  3. Alpha-induced reactions on selenium between 11 and 15 MeV

    Science.gov (United States)

    Fiebiger, Stefan; Slavkovská, Zuzana; Giesen, Ulrich; Göbel, Kathrin; Heftrich, Tanja; Heiske, Annett; Reifarth, René; Schmidt, Stefan; Sonnabend, Kerstin; Thomas, Benedikt; Weigand, Mario

    2017-07-01

    The production of 77,79,85,85m Kr and 77Br via the reaction Se(α ,x) was investigated between {E}α =11 and 15 MeV using the activation technique. The irradiation of natural selenium targets on aluminum backings was conducted at the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig, Germany. The spectroscopic analysis of the reaction products was performed using a high-purity germanium detector located at PTB and a low energy photon spectrometer detector at the Goethe University Frankfurt, Germany. Thick-target yields were determined. The corresponding energy-dependent production cross sections of 77,79,85,85m Kr and 77Br were calculated from the thick-target yields. Good agreement between experimental data and theoretical predictions using the TALYS-1.6 code was found.

  4. Elastic and inelastic scattering of 2 to 10 MeV protons by lithium isotopes; Diffusion elastique et inelastique des protons de 2 a 10 MeV par les isotopes du lithium

    Energy Technology Data Exchange (ETDEWEB)

    Laurat, M [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten {mu}g/cm{sup 2}) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of {sup 8}Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [French] Nous decrivons le dispositif experimental mis au point pour effectuer les mesures de spectrometrie et de section efficace absolue pour les reactions induites par des protons acceleres par un Van de Graaff Tandem 12 MeV. Les particules sont detectees par des jonctions au silicium, le poids des cibles (de l'ordre d'une dizaine de {mu}g/cm{sup 2}), mesure par la methode du quartz. L'ensemble de l'appareillage a ete controle par l'etude de la diffusion des protons par le lithium 6, et nous a permis de preciser les diffusions elastiques et inelastiques (excitation du 1er niveau) des protons de 2 a 9 MeV par le lithium 7. La structure observee a permis de determiner les spin et parite les plus probables de six niveaux du {sup 8}Be entre 19 et 25 MeV d'energie d'excitation. (auteur)

  5. Elastic and inelastic scattering of 2 to 10 MeV protons by lithium isotopes; Diffusion elastique et inelastique des protons de 2 a 10 MeV par les isotopes du lithium

    Energy Technology Data Exchange (ETDEWEB)

    Laurat, M. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    A description is given of the experimental set-up which has been devised for carrying out spectrometric and absolute cross-section measurements on the reactions induced by protons accelerated in a 12 MeV Van de Graaff Tandem. The particles are detected by silicon junctions; the weight of the targets (about ten {mu}g/cm{sup 2}) is determined by the quartz method. The experimental equipment has been controlled by a study of proton scattering by lithium-6, and has made it possible to evaluate the elastic and inelastic scattering (1. level excitation) by lithium 7 of 2 to 9 MeV protons. The most probable spin and parity values for the six levels of {sup 8}Be between 19 and 25 MeV excitation energy have been determined from a knowledge of the observed structure. (author) [French] Nous decrivons le dispositif experimental mis au point pour effectuer les mesures de spectrometrie et de section efficace absolue pour les reactions induites par des protons acceleres par un Van de Graaff Tandem 12 MeV. Les particules sont detectees par des jonctions au silicium, le poids des cibles (de l'ordre d'une dizaine de {mu}g/cm{sup 2}), mesure par la methode du quartz. L'ensemble de l'appareillage a ete controle par l'etude de la diffusion des protons par le lithium 6, et nous a permis de preciser les diffusions elastiques et inelastiques (excitation du 1er niveau) des protons de 2 a 9 MeV par le lithium 7. La structure observee a permis de determiner les spin et parite les plus probables de six niveaux du {sup 8}Be entre 19 et 25 MeV d'energie d'excitation. (auteur)

  6. Surface enrichment with chrome and nitriding of IF steel under an abnormal glow discharge

    International Nuclear Information System (INIS)

    Meira, S.R.; Borges, P.C.; Bernardelli, E.A.

    2014-01-01

    The objective of this work is to evaluate the influence of surface enrichment of IF steel with chrome, and nitriding, the formation of the nitrided layer. Thus, IF steel samples were subjected to surface enrichment process, using 409 stainless steel as a target for sputtering, followed by plasma nitriding, both under a dc abnormal glow discharge. The enrichment treatment was operated at 1200 ° C for 3h. The nitriding treatment was operated at 510 ° C for 2 h. The influence of the treatments on the layers formed was studied through optical microscopy (OM), scan electron microscopy (SEM), X-ray diffraction (XRD) and Vickers microindentation. The results show that the enrichment is effective to enrich the IF surface, furthermore, improves the characteristics of nitriding, comparing nitriding samples to nitriding and enriched, was observed needles of nitrides, as well as a higher hardness, which is associated with the nitrides of chrome, on the nitriding and enriched samples. (author)

  7. Photoneutron source based on a compact 10 MeV betatron

    International Nuclear Information System (INIS)

    Bell, Z.W.; Chaklov, V.L.; Golovkov, V.M.

    1998-01-01

    Accelerator-based photoneutron sources have enjoyed wide use and offer the advantages of long term stability, ease of control and absence of radioactive materials. The authors report here measurements of the yield of photoneutrons from a neutron generator using a compact betatron (466 kg total weight, 900 by 560 by 350 mm betatron dimensions) at the Institute of Introscopy of the Tomsk Polytechnic University. Electrons were accelerated to energies up to 10 MeV and produced a bremsstrahlung beam with a dose rate of 0.16 Gy/min (at 10 MeV, 1 meter from the bremsstrahlung target) to irradiate LiD, Be, depleted U, and Pb neutron-producing targets. The angular distributions of photoneutrons produced by bremsstrahlung beams were measured with a long counter and integrated to determine neutron yield. In addition, neutron time of flight spectra were recorded from all targets using a 15 meter flight path perpendicular to the photon beam. The maximum observed yields were 5.2 x 10 4 n/rad/gram target obtained with LiD, 1.7 x 10 4 n/rad/gram from Be, 3.3 x 10 3 n/rad/gram from U, and 7.5 x 10 2 n/rad/gram from Pb. Optimization of target dimensions, shape, and positioning is expected to increase the yield from the LiD target by a factor of 35. With the increased yield, this compact betatron-based system could find application in the interrogation of waste containers for fissile material

  8. Hybridization Capture Using Short PCR Products Enriches Small Genomes by Capturing Flanking Sequences (CapFlank)

    DEFF Research Database (Denmark)

    Tsangaras, Kyriakos; Wales, Nathan; Sicheritz-Pontén, Thomas

    2014-01-01

    , a non-negligible fraction of the resulting sequence reads are not homologous to the bait. We demonstrate that during capture, the bait-hybridized library molecules add additional flanking library sequences iteratively, such that baits limited to targeting relatively short regions (e.g. few hundred...... nucleotides) can result in enrichment across entire mitochondrial and bacterial genomes. Our findings suggest that some of the off-target sequences derived in capture experiments are non-randomly enriched, and that CapFlank will facilitate targeted enrichment of large contiguous sequences with minimal prior...

  9. Increased phylogenetic resolution using target enrichment in Rubus

    Science.gov (United States)

    Phylogenetic analyses in Rubus L. have been challenging due to polyploidy, hybridization, and apomixis within the genus. Wide morphological diversity occurs within and between species, contributing to challenges at lower and higher systematic levels. Phylogenetic inferences to date have been based o...

  10. Targeted enrichment strategies for next-generation plant biology

    Science.gov (United States)

    Richard Cronn; Brian J. Knaus; Aaron Liston; Peter J. Maughan; Matthew Parks; John V. Syring; Joshua. Udall

    2012-01-01

    The dramatic advances offered by modem DNA sequencers continue to redefine the limits of what can be accomplished in comparative plant biology. Even with recent achievements, however, plant genomes present obstacles that can make it difficult to execute large-scale population and phylogenetic studies on next-generation sequencing platforms. Factors like large genome...

  11. GSL-enriched membrane microdomains in innate immune responses.

    Science.gov (United States)

    Nakayama, Hitoshi; Ogawa, Hideoki; Takamori, Kenji; Iwabuchi, Kazuhisa

    2013-06-01

    Many pathogens target glycosphingolipids (GSLs), which, together with cholesterol, GPI-anchored proteins, and various signaling molecules, cluster on host cell membranes to form GSL-enriched membrane microdomains (lipid rafts). These GSL-enriched membrane microdomains may therefore be involved in host-pathogen interactions. Innate immune responses are triggered by the association of pathogens with phagocytes, such as neutrophils, macrophages and dendritic cells. Phagocytes express a diverse array of pattern-recognition receptors (PRRs), which sense invading microorganisms and trigger pathogen-specific signaling. PRRs can recognize highly conserved pathogen-associated molecular patterns expressed on microorganisms. The GSL lactosylceramide (LacCer, CDw17), which binds to various microorganisms, including Candida albicans, is expressed predominantly on the plasma membranes of human mature neutrophils and forms membrane microdomains together with the Src family tyrosine kinase Lyn. These LacCer-enriched membrane microdomains can mediate superoxide generation, migration, and phagocytosis, indicating that LacCer functions as a PRR in innate immunity. Moreover, the interactions of GSL-enriched membrane microdomains with membrane proteins, such as growth factor receptors, are important in mediating the physiological properties of these proteins. Similarly, we recently found that interactions between LacCer-enriched membrane microdomains and CD11b/CD18 (Mac-1, CR3, or αMβ2-integrin) are significant for neutrophil phagocytosis of non-opsonized microorganisms. This review describes the functional role of LacCer-enriched membrane microdomains and their interactions with CD11b/CD18.

  12. PWR fuel of high enrichment with erbia and enriched gadolinia

    International Nuclear Information System (INIS)

    Bejmer, Klaes-Håkan; Malm, Christian

    2011-01-01

    Today standard PWR fuel is licensed for operation up to 65-70 MWd/kgU, which in most cases corresponds to an enrichment of more than 5 w/o "2"3"5U. Due to criticality safety reason of storage and transportation, only fuel up to 5 w/o "2"3"5U enrichment is so far used. New fuel storage installations and transportation casks are necessary investments before the reactivity level of the fresh fuel can be significantly increased. These investments and corresponding licensing work takes time, and in the meantime a solution that requires burnable poisons in all pellets of the fresh high-enriched fuel might be used. By using very small amounts of burnable absorber in every pellet the initial reactivity can be reduced to today's levels. This study presents core calculations with fuel assemblies enriched to almost 6 w/o "2"3"5U mixed with a small amount of erbia. Some of the assemblies also contain gadolinia. The results are compared to a reference case containing assemblies with 4.95 w/o "2"3"5U without erbia, utilizing only gadolinia as burnable poison. The comparison shows that the number of fresh fuel assemblies can be reduced by 21% (which increases the batch burnup by 24%) by utilizing the erbia fuel concept. However, increased cost of uranium due to higher enrichment is not fully compensated for by the cost gain due to the reduction of the number assemblies. Hence, the fuel cycle cost becomes slightly higher for the high enrichment erbia case than for the reference case. (author)

  13. Measure of back angle cross sections of antiproton-nucleus elastic scattering at 48 and 180 MeV

    International Nuclear Information System (INIS)

    Berrada, M.

    1986-04-01

    Antiproton-nucleus elastic scattering was studied in the LEAR ring at CERN. The scattering cross section at back angles (θ LAB = 142 to 164 deg inclusive) was measured using plastic scintillation detectors. Analysis of experimental data at 47 MeV for a CH target and at 182 MeV for CH, C12, 016, and 018 targets produces differential cross sections for back angles less than or equal to a few dozen microbarns. These results agree with theoretical microscopic predictions. The analysis improves understanding of antiproton-nucleus interaction and introduces a constraint on the construction of optical potentials. The antiproton-nucleus potential is shown to be highly absorbing, thereby excluding S type potentials, and removing the ambiguity arising from the analysis of antiprotonic atoms. The results also show that there is no attractive pocket in the real potential likely to lead to an increase of the back angle cross sections [fr

  14. Characterization of oxygen dimer-enriched silicon detectors

    CERN Document Server

    Boisvert, V; Moll, M; Murin, L I; Pintilie, I

    2005-01-01

    Various types of silicon material and silicon p+n diodes have been treated to increase the concentration of the oxygen dimer (O2i) defect. This was done by exposing the bulk material and the diodes to 6 MeV electrons at a temperature of about 350 °C. FTIR spectroscopy has been performed on the processed material confirming the formation of oxygen dimer defects in Czochralski silicon pieces. We also show results from TSC characterization on processed diodes. Finally, we investigated the influence of the dimer enrichment process on the depletion voltage of silicon diodes and performed 24 GeV/c proton irradiations to study the evolution of the macroscopic diode characteristics as a function of fluence.

  15. Measurements and Monte Carlo calculations of neutron production cross-sections at 180{sup o} for the 140 MeV proton incident reactions on carbon, iron, and gold

    Energy Technology Data Exchange (ETDEWEB)

    Iwamoto, Yosuke, E-mail: iwamoto.yosuke@jaea.go.j [Japan Atomic Energy Agency, 2-4, Shirakatashirane, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Satoh, Daiki [Japan Atomic Energy Agency, 2-4, Shirakatashirane, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Hagiwara, Masayuki [KEK (Japan); Yashima, Hiroshi [Kyoto University (Japan); Nakane, Yoshihiro [Japan Atomic Energy Agency, 2-4, Shirakatashirane, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Tamii, Atsushi [Research Center for Nuclear Physics, Osaka University (Japan); Iwase, Hiroshi [KEK (Japan); Endo, Akira; Nakashima, Hiroshi; Sakamoto, Yukio [Japan Atomic Energy Agency, 2-4, Shirakatashirane, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Hatanaka, Kichiji [Research Center for Nuclear Physics, Osaka University (Japan); Niita, Koji [Research Organization for Information Science and Technology (Japan)

    2010-08-21

    The neutron production cross-sections of carbon, iron, and gold targets with 140 MeV protons at 180{sup o} were measured at the RCNP cyclotron facility. The time-of-flight technique was used to obtain the neutron energy spectra in the energy range above 1 MeV. The carbon and iron target results were compared with the experimental data from 113 MeV (p,xn) reactions at 150{sup o} reported by Meier et al. Our data agreed well with them in spite of different incident energies and angles. Calculations were then performed using different intra-nuclear cascade models (Bertini, ISOBAR, and JQMD) implemented with PHITS code. The results calculated using the ISOBAR and JQMD models roughly agreed with the experimental iron and gold target data, but the Bertini could not reproduce the high-energy neutrons above 10 MeV.

  16. High enrichment to low enrichment core's conversion. Accidents analysis

    International Nuclear Information System (INIS)

    Abbate, P.; Rubio, R.; Doval, A.; Lovotti, O.

    1990-01-01

    This work analyzes the different accidents that may occur in the reactor's facility after the 20% high-enriched uranium core's conversion. The reactor (of 5 thermal Mw), built in the 50's and 60's, is of the 'swimming pool' type, with light water and fuel elements of the curve plates MTR type, enriched at 93.15 %. This analysis includes: a) accidents by reactivity insertion; b) accidents by coolant loss; c) analysis by flow loss and d) fission products release. (Author) [es

  17. Study of neutron spectra in extended uranium target. New experimental data

    Directory of Open Access Journals (Sweden)

    Paraipan M.

    2017-01-01

    Full Text Available The spatial distribution of neutron fluences in the extended uranium target (“Quinta” assembly irradiated with 0.66 GeV proton, 4 AGeV deuteron and carbon beams was studied using the reactions with different threshold energy (Eth. The data sets were obtained with 59Co samples. The accumulation rates for the following isotopes: 60Co (Eth 0 MeV, 59Fe (Eth 3 MeV, 58Co (Eth 10 MeV, 57Co (Eth 20 MeV, 56Co (Eth 32 MeV, 47Sc (Eth 55 MeV, and 48V (Eth 70 MeV were measured with HPGe spectrometer. The experimental accumulation rates were compared with the predictions of the simulations with Geant4 code. Substantial difference between the reconstructed and the simulated data for the hard part of the neutron spectrum was analyzed.

  18. A 2000-2010 years outlook of isotopic uranium enrichment

    International Nuclear Information System (INIS)

    Vasaru, G.

    1998-01-01

    The increase of the installed power in nuclear plants implies the following steps to be achieved: - developing a parallel industry for the nuclear fuel cycle able to ensure a rhythmic supply of natural uranium, possibly an isotopic enrichment of 235 U of around 1.2 - 3.2%, depending on the reactor system; - manufacturing the fuel elements and the operation of cycle back-end, which may, possibly, include a temporary storage of the irradiated fuel; - reprocessing the spend fuel; - radioactive waste processing in view of final disposal, as well as the recovery of un-spent uranium and of plutonium formed. The heavy water reactors of CANDU-PHW does not imply any isotopic enrichment but provides a lower burnup of only 7,000 MW day/tone. An enrichment to 1.2% in 235 U for this type of reactors could increase the burnup up to 20,000 MW day/tone. An advanced method of enriching 235 U is based on the Atomic Vapor Laser Isotop Separation (AVLIS). This procedure called AVLIS has several advantages which are pointed out in this paper, among which: a very high selectivity; high separation factors; a low energy consumption due to the fact that in the conditions of a selective photo ionization, the energy necessary to the process is only 6.2 eV for the separated 235 U atom vs 0.3 MeV in case of inertial separators or 3 MeV in case of gaseous diffusion procedure. With the current laser yields an energy consumption of 100 kWh/SWU is estimated for AVLIS procedures as compared with 2,400 kWh/SWU in case of gaseous diffusion; an almost entire extraction of 235 U, what ensures a more efficient utilisation of nuclear fuel. Due to its modular character and to potential improvement in the equipment which could be achieved, this procedure will ensure a reduction in the investment costs in the construction stage what will make AVLIS a substitute of the classical separation procedures

  19. Gaseous diffusion -- the enrichment workhorse

    International Nuclear Information System (INIS)

    Shoemaker, J.E. Jr.

    1984-01-01

    Construction of the first large-scale gaseous diffusion facility was started as part of the Manhattan Project in Oak Ridge, Tennessee, in 1943. This facility, code named ''K-25,'' began operation in January 1945 and was fully on stream by September 1945. Four additional process buildings were later added in Oak Ridge as the demand for enriched uranium escalated. New gaseous diffusion plants were constructed at Paducah, Kentucky, and Portsmouth, Ohio, during this period. The three gaseous diffusion plants were the ''workhorses'' which provided the entire enriched uranium demand for the United States during the 1950s and 1960s. As the demand for enriched uranium for military purposes decreased during the early 1960s, power to the diffusion plants was curtailed to reduce production. During the 1960s, as plans for the nuclear power industry were formulated, the role of the diffusion plants gradually changed from providing highly-enriched uranium for the military to providing low-enriched uranium for power reactors

  20. Uranium enrichment. Technology, economics, capacity

    International Nuclear Information System (INIS)

    Voigt, W.R. Jr.; Saire, D.E.; Gestson, D.K.; Peske, S.E.; Vanstrum, P.R.

    1983-01-01

    Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R+D efforts on various processes. (author)

  1. Uranium enrichment: technology, economics, capacity

    Energy Technology Data Exchange (ETDEWEB)

    Voigt, Jr., W. R.; Vanstrum, P. R.; Saire, D. E.; Gestson, D. K.; Peske, S. E.

    1982-08-01

    Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R and D efforts on various processes.

  2. Uranium enrichment: technology, economics, capacity

    International Nuclear Information System (INIS)

    Voigt, W.R. Jr.; Vanstrum, P.R.; Saire, D.E.; Gestson, D.K.; Peske, S.E.

    1982-01-01

    Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R and D efforts on various processes

  3. Study of {sup 24}Na activity in concrete using 20-MeV proton beam on Cu

    Energy Technology Data Exchange (ETDEWEB)

    Oranj, Leila Mokhtanri; Jung, Nam Suk; Lee, Arim; Heo, Tae Min; Bakhtian, Mahdi; Lee, Hee Seock [POSTECH, Pohang (Korea, Republic of)

    2017-04-15

    The number of medical cyclotrons capable of accelerating protons to about 20 MeV is increasing in Korea. In such facilities, various radionuclides could be induced in shielding materials like concrete from secondary neutrons which Causes problems from the view point of radiation safety. Among these radionuclides, gamma-ray from {sup 24}Na (Tz1/2 = 15 h) is the most important origin of radiation exposure. {sup 24}Na could be produced from secondary neutrons on Na, Al and Mg component which exist in the concrete. {sup 24} Na Could be produced from thermal neutrons on Na and fast neutron with energy lower than 20 MeV on Al and Mg. Due to interaction of 20 MeV protons on Cu target, secondary neutrons with the energy of less than 20 MeV were produced. therefore, among the concrete components, Na, Al and Mg are only corespondent to produce {sup 24}Na. In this work, {sup 24}Na activity induced in concrete and chemical reagents of concrete (NaHCO{sub 3}, Al{sub 2}O{sub 3} and MgO) were measured. To produce neutrons, Cu target was irradiated by 20 MeV protons. Measured data were compared with results of simulations by FLUKA and MARS as well as earlier works and theocratical data. In the case of Mg and Al chemical reagents, FLUKA code overestimates our measurements by approximately four times, while, for Na sample, FLUKA underestimates the experimental data by almost 0.5. Data from FLUKA and measurement for the concrete are consistent. Calculation from TALYS for Mg overestimates the measured data by a factor of 2.5.

  4. Measurement of energy deposition distributions produced in cylindrical geometry by irradiation with 15 MeV neutrons

    International Nuclear Information System (INIS)

    Brandan, M.E.

    1979-01-01

    Cellular survival experiments have shown that the biological damage induced by radiation depends on the density of energy deposition along the trajectory of the ionizing particle. The quantity L is defined to measure the density of energy transfer along a charged particle's trajectory. It is equal to sigma/l, where sigma is the energy transferred to a medium and l is the path length along which the transfer takes place. L is the stochastic quantity whose mean value is the unrestricted linear energy transfer, L/sub infinity/. Measurements of the distribution of L in a thin medium by secondary charged particles from fast neutron irradiation were undertaken. A counter operating under time coincidence between two coaxial cylindrical detectors was designed and built for this purpose. Secondary charged particles enter a gas proportional counter and deposit some energy sigma. Those particles traversing the chamber along a radial trajectory strike a CsI scintillator. A coincidence between both detectors' signals selects a known path length for these events, namely the radius of the cavity. Measurements of L distributions for l = 1 μm in tissue were obtained for 3 and 15 MeV neutron irradiation of a tissue-equivalent target wall and for 15 MeV neutron irradiation of a graphite wall. Photon events were corrected for by measurements with a Pb target wall and 15 MeV neutron irradiation as well as exposure to a pure photon field. The measured TE wall distributions with 15 MeV neutron bombardment show contributions from protons, α-particles, 9 Be and 12 C recoils. The last three comprise the L distribution for irradiation of the graphite wall. The proton component of the measured L distributions at 3 and 15 MeV was compared to calculated LET distributions

  5. Environmental Enrichment Mitigates Deficits after Repetitive Mild Traumatic Brain Injury.

    Science.gov (United States)

    Liu, Xixia; Qiu, Jianhua; Alcon, Sasha; Hashim, Jumana; Meehan, William P; Mannix, Rebekah

    2017-08-15

    Although environmental enrichment has been shown to improve functional and histologic outcomes in pre-clinical moderate-to-severe traumatic brain injury (TBI), there are a paucity of pre-clinical data regarding enrichment strategies in the setting of repetitive mild traumatic brain injury (rmTBI). Given the vast numbers of athletes and those in the military who sustain rmTBI, the mounting evidence of the long-term and progressive sequelae of rmTBI, and the lack of targeted therapies to mitigate these sequelae, successful enrichment interventions in rmTBI could have large public health significance. Here, we evaluated enrichment strategies in an established pre-clinical rmTBI model. Seventy-one male C57BL/6 mice were randomized to two different housing conditions, environmental enrichment (EE) or normal condition (NC), then subjected to rmTBI injury (seven injuries in 9 days) or sham injury (anesthesia only). Functional outcomes in all four groups (NC-TBI, EE-TBI, NC-sham, and EE-sham) were assessed by motor, exploratory/anxiety, and mnemonic behavioral tests. At the synaptic level, N-methyl d-aspartate receptor (NMDAR) subunit expression of phosphorylated glutamate receptor 1 (GluR1), phosphorylated Ca 2+ /calmodulin-dependent protein kinase II (CaMKII), and calpain were evaluated by western blot. Compared to injured NC-TBI mice, EE-TBI mice had improved memory and decreased anxiety and exploratory activity post-injury. Treatment with enrichment also corresponded to normal NMDAR subunit expression, decreased GluR1 phosphorylation, decreased phosphorylated CaMKII, and normal calpain expression post-rmTBI. These data suggest that enrichment strategies may improve functional outcomes and mitigate synaptic changes post-rmTBI. Given that enrichment strategies are feasible in the clinical setting, particularly for athletes and soldiers for whom the risk of repetitive injury is greatest, these data suggest that clinical trials may be warranted.

  6. A 30 MeV H- cyclotron for isotope production

    International Nuclear Information System (INIS)

    Baartman, R.; Kleevan, W.J.; Laxdal, R.E.; Milton, B.F.; Otter, A.J.; Pearson, J.B.; Poirier, R.L.; Schmor, P.W.; Schneider, H.R.; Erdman, K.L.; Walker, Q.

    1989-01-01

    Because of an expanding market for radioisotopes there is a need for a new generation of cyclotrons designed specifically for this purpose. We describe such a cyclotron currently under construction. It is a 30 MeV H - design that exploits a newly developed high brightness multicusp ion source which is capable of H - currents of up to 5 mA. This together with careful beam matching then makes feasible accelerated H - beam intensities of 500 μA. The cyclotron being built is a four sector radial ridge design with two 45 degree dees in opposite valleys. Beam extraction is by stripping to H + in a thin graphite foil. Two extraction probes will allow simultaneous extraction of two beams, each with an intensity of up to 200 μA. Energy variation from 15 MeV to 30 MeV is achieved by varying the radial position of the extraction foil. 7 refs., 4 figs., 1 tab

  7. Measurement of parity nonconservation in the proton-proton total cross section at 800 MeV

    International Nuclear Information System (INIS)

    Bowman, J.D.

    1986-01-01

    A report is made of a measurement of parity nonconservation in the transmission of 800-MeV longitudinally polarized protons through an unpolarized, 1-m liquid-hydrogen target. The dependence of transmission on beam properties was studied to measure and to correct for systematic errors. The measured longitudinal asymmetry in the total cross section is A/sub L/ = [+2.4 +- 1.1 (statistical) +- 0.1 (systematic)] x 10 -7 . 25 refs., 2 figs

  8. Investigation of transversal nuclear excitation in 208Pb at excitation energies between 6 MeV and 8 MeV using inelastic electron scattering

    International Nuclear Information System (INIS)

    Frey, R.W.

    1978-01-01

    Using high resolution inelastic electron scattering magnitic dipole and quadrupole excitations in 208 Pb were investigated in the energy range between 6 MeV and 8 MeV. The electron energy was 50 MeV and 63.5 MeV. With a mean absolute energy resolution of 33 kev. 44 excited states were found in the above energy range. The measured angular distributions were compared with DWBA-calculations using random phase approximated wave functions. (FKS)

  9. A Systematic Approach to Marital Enrichment.

    Science.gov (United States)

    Dinkmeyer, Don; Carlson, Jon

    1986-01-01

    Presents a systematic approach to enriching marital relationships. The history and current status of marital enrichment is reviewed. An Adlerian approach to marital enrichment is described. Applications of the program in enrichment groups, marriage therapy and couple groups are included. (Author)

  10. Experimental observation of Z-dependence of saturation depth of 0.662 MeV multiply scattered gamma rays

    International Nuclear Information System (INIS)

    Singh, Gurvinderjit; Singh, Manpreet; Singh, Bhajan; Sandhu, B.S.

    2006-01-01

    The gamma photons continue to soften in energy as the number of scatterings increases in the sample having finite dimensions both in depth and lateral dimensions. The number of multiply scattered photons increases with an increase in target thickness and saturates at a particular value of the target thickness known as saturation depth. The present experiment is undertaken to study the effect of atomic number of the target on saturation depth of 0.662 MeV incident gamma photons multiply scattered from targets of various thicknesses. The scattered photons are detected by an HPGe gamma detector placed at 90 o to the incident beam direction. We observe that with an increase in target thickness, the number of multiply scattered photons also increases and saturates at a particular value of the target thickness. The saturation depth decreases with increasing atomic number. The double Compton scattered peak is also observed in the experimental spectra

  11. Conversion efficiency of lead for 30-200 MeV photons

    International Nuclear Information System (INIS)

    Darriulat, P.; Gygi, E.; Holder, M.; McDonald, K.T.; Pugh, H.G.; Schneider, F.; Tittel, K.

    1975-01-01

    The conversion efficiency of lead has been measured as a function of thickness for 44 MeV, 94 MeV and 177 MeV photons, and as a function of energy between 29 MeV and 177 Mev for thickness of one and two radiation lengths. Some additional information on multiplicity of secondary tracks and on their angular distribution was obtained using a small streamer chamber. The results obtained confirm the shower calculations of Messel and Crawford. (Auth.)

  12. Enrichment of light hydrocarbon mixture

    Science.gov (United States)

    Yang,; Dali, [Los Alamos, NM; Devlin, David [Santa Fe, NM; Barbero, Robert S [Santa Cruz, NM; Carrera, Martin E [Naperville, IL; Colling, Craig W [Warrenville, IL

    2010-08-10

    Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

  13. PC based uranium enrichment analyser

    International Nuclear Information System (INIS)

    Madan, V.K.; Gopalakrishana, K.R.; Bairi, B.R.

    1991-01-01

    It is important to measure enrichment of unirradiated nuclear fuel elements during production as a quality control measure. An IBM PC based system has recently been tested for enrichment measurements for Nuclear Fuel Complex (NFC), Hyderabad. As required by NFC, the system has ease of calibration. It is easy to switch the system from measuring enrichment of fuel elements to pellets and also automatically store the data and the results. The system uses an IBM PC plug in card to acquire data. The card incorporates programmable interval timers (8253-5). The counter/timer devices are executed by I/O mapped I/O's. A novel algorithm has been incorporated to make the system more reliable. The application software has been written in BASIC. (author). 9 refs., 1 fig

  14. The JHP 200-MeV proton linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Takao [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)

    1997-11-01

    A 200-MeV proton linear accelerator for the Japanese Hadron Project (JHP) has been designed. It consists of a 3-MeV radio-frequency quadrupole linac (RFQ), a 50-MeV drift tube linac (DTL) and a 200-MeV separated-type drift tube linac (SDTL). A frequency of 324 MHz has been chosen for all of the rf structures. A peak current of 30 mA (H{sup -} ions) of 400 {mu}sec pulse duration will be accelerated at a repetition rate of 25 Hz. A future upgrade plan up to 400 MeV is also presented, in which annular-coupled structures (ACS) of 972 MHz are used in an energy range of above 150 or 200 MeV. One of the design features is its high performance for a beam-loss problem during acceleration. It can be achieved by separating the transition point in the transverse motion from that of the longitudinal motion. The transverse transition at a rather low-energy range decreases the effects of space-charge, while the longitudinal transition at a rather high-energy range decreases the effects of nonlinear problems related to acceleration in the ACS. Coupled envelope equations and equipartitioning theory are used for the focusing design. The adoption of the SDTL structure improves both the effective shunt impedance and difficulties in fabricating drift tubes with focusing magnets. An accurate beam-simulation code on a parallel supercomputer was used for confirming any beam-loss problem during acceleration. (author)

  15. Production of radionuclides by 14 MeV neutron generator

    International Nuclear Information System (INIS)

    Alfassi, Z.B.

    1983-01-01

    Due to the short half-lives of these nuclides they have to be produced in situ or at least not far from the place of use. The cost of 14 MeV neutron generators have been compared with the typical middle-sized cyclotrons and it was found that the capital costs are much lower in the case of neutron generators. This is the main reason for the availability of 14 MeV neutron generators in many scientific institutes compared to the scarcity of cyclotrons. Lately, the use of 14 MeV neutrons for cancer therapy was studied in several medical centers. A number of hospitals and cancer research centers have high intensity 14 MeV neutron generators for this purpose. The advantages of using short-lived in-house produced radionuclides suggest the use of the available 14 MeV neutron generators for biological studies and in medical diagnosis. 14 MeV neutron generators can be used to produce some of the medically useful radionuclides, such as /sup 18/F, /sup 80/Br, /sup 199m/Hg, and others. However, the amount required for medicine can only be prepared by the new high intensity neutron generators, used for neutron therapy and not by the smaller ones, commonly used in university laboratories (--10/sup 11/ n/sec). On the other hand, these relatively small neutron generators can be used for the preparation of radionuclides for biological studies. They facilitate the study of metabolism of elements for which radionuclides cannot be usually purchased due to short half-lives or the high price of the long-lived ones, such as /sup 34m/Cl, /sup 18/F, /sup 28,29/Al, /sup 27/Mg, and others. An example is the work done on the fate of Al and Mg in rats using /sup 28/Al and /sup 27/Mg./sup 13/

  16. Advances in uranium enrichment processes

    International Nuclear Information System (INIS)

    Rae, H.K.; Melvin, J.G.; Slater, J.B.

    1986-05-01

    Advances in gas centrifuges and development of the atomic vapour laser isotope separation process promise substantial reductions in the cost of enriched uranium. The resulting reduction in LWR fuel costs could seriously erode the economic advantage of CANDU, and in combination with LWR design improvements, shortened construction times and increased operational reliability could allow the LWR to overtake CANDU. CANDU's traditional advantages of neutron economy and high reliability may no longer be sufficient - this is the challenge. The responses include: combining neutron economy and dollar economy by optimizing CANDU for slightly enriched uranium fuel; developing cost-reducing improvements in design, manufacture and construction; and reducing the cost of heavy water. Technology is a renewable resource which must be continually applied to a product for it to remain competitive in the decades to come. Such innovation is a prerequisite to Canada increasing her share of the international market for nuclear power stations. The higher burn-up achievable with enriched fuel in CANDU can reduce the fuel cycle costs by 20 to 40 percent for a likely range of costs for yellowcake and separative work. Alternatively, some of the benefits of a higher fissile content can take the form of a cheaper reactor core containing fewer fuel channels and less heavy water, and needing only a single fuelling machine. An opportunity that is linked to this need to introduce an enriched uranium fuel cycle into CANDU is to build an enrichment business in Canada. This could offer greater value added to our uranium exports, security of supply for enriched CANDUs, technological growth in Canada and new employment opportunities. AECL has a study in progress to define this opportunity

  17. Crosslinking of commercial polyethylenes by 10 MeV electrons

    International Nuclear Information System (INIS)

    Singh, A.; Lopata, V.J.; Kremers, W.; Sze, Yu-keung

    1995-08-01

    Commercial polyethylenes were irradiated with 10 MeV electrons to induce crosslinking. The gel fraction data measured as a function of total dose suggests that crosslinking proceeds on irradiation, as expected. A number of the properties of the irradiated polyethylenes, such as the degree of oxidation, crystallinity and thermal degradation, were studied by Fourier transform infrared/photo acoustic spectroscopy, X-ray diffraction, and a pyrolysis technique coupled with gas chromatography and mass spectrometry. The results of this study suggest that commercial polyethylenes can be crosslinked to a gel fraction of ∼70%, required for wire and cable applications, by 10 MeV electrons. (author). 35 refs., 6 figs

  18. A P + DEUTERON PROTON POLARIMETER AT 200 MEV.

    Energy Technology Data Exchange (ETDEWEB)

    HUANG,H.; ROSER,T.; ZELENSKI,A.; KURITA,K.; STEPHENSON,E.; TOOLE,R.

    2002-06-02

    There has been concern about the analyzing power of the p-Carbon polarimeter at the end of 200 MeV LINAC of BNL. A new polarimeter based on proton-deuteron scattering was installed and we have repeated the calibration of proton-Carbon scattering at 12 degrees and 200 MeV against proton-deuteron scattering. The result is consistent with the value of A=0.62 now used to measure the beam polarization at the end of the LINAC.

  19. Observation of correlation between two fast protons in proton-nucleus interactions at 640 MeV

    International Nuclear Information System (INIS)

    Komarov, V.I.; Kosarev, G.E.

    1978-01-01

    The measurements have been performed to observe correlations between backward emitted protons (BEP) and forward outgoing protons from quasi-free scattering of the incident proton of 640 MeV on a nucleons pair [pN] within Be, C, Al, Cu and Pb nucleus at the angles 12 deg and 122 deg: p 0 + pN → p 1 + N + p 3 . Here p 1 is a proton detected in coincidence with BEP p 3 and N is a nucleon unobserved under the conditions of this experiment. The differential cross sections for the BEP of energies from 50 to 145 MeV have been measured in coincidence with forward outgoing protons (255 to 330 MeV) by scintillation counter method. The inclusive BEP spectra have been explained by the quasi-elastic backscattering on clusters which do not break up during the interaction. The calculated distribution are remarkably narrower than the experimental anes. The measurements point out that the discussed production of two fast protons is observable with all the targets and the cross section per target nucleon decreases with increasing the target mass number

  20. Uranium enriched granites in Sweden

    International Nuclear Information System (INIS)

    Wilson, M.R.; Aakerblom, G.

    1980-01-01

    Granites with uranium contents higher than normal occur in a variety of geological settings in the Swedish Precambrian, and represent a variety of granite types and ages. They may have been generated by (1) the anatexis of continental crust (2) processes occurring at a much greater depth. They commonly show enrichement in F, Sn, W and/or Mo. Only in one case is an important uranium mineralization thought to be directly related to a uranium-enriched granite, while the majority of epigenetic uranium mineralizations with economic potential are related to hydrothermal processes in areas where the bedrock is regionally uranium-enhanced. (Authors)

  1. Uranium enrichment. 1980 annual report

    International Nuclear Information System (INIS)

    1981-05-01

    This report contains data and related information on the production of enriched uranium at the gaseous diffusion plants and an update on the construction and project control center for the gas centrifuge plant. Power usage at the gaseous diffusion plants is illustrated. The report contains several glossy color pictures of the plants and processes described. In addition to gaseous diffusion and the centrifuge process, three advanced isotope separation process are now being developed. The business operation of the enrichment plants is described; charts on revenue, balance sheets, and income statements are included

  2. Projectile-like fragments from 129Xe+natCu reactions at E/A = 40 MeV

    International Nuclear Information System (INIS)

    Russ, D.E.; Mignerey, A.C.; Garcia-Solis, E.J.

    1996-01-01

    The bombarding of heavy nuclei with energetic heavy projectiles has been one of the most important experimental tools for nuclear science. At low beam energies, (E/A) beam 100 MeV, these mean field effects are less important and nucleon-nucleon interactions dominate. Within the intermediate energy region, the situation is less clear because of both the mean field and nucleon-nucleon effects contribute. There is no consensus on the theoretical treatment of nuclear reaction in the intermediate energy regime and statistical, dynamical, and hybrid models have been used with limited success. Previous studies of 136 Xe + 209 Bi at E/A = 28 MeV carried out at Michigan State University (MSU) have been well described by a damped reaction mechanism. On the other hand, 129 Xe + nat Cu at E/A = 50 MeV also at MSU has been compared with a hybrid model with reasonable success. In order to see a transition from a damped reaction mechanism to more fragmentation-like processes, an experiment was carried out at MSU using 129 Xe beams at E/A = 30, 40, 50, and 60 MeV. The targets were Cu, Sc, and Au. The current study only looks at the projectile-like fragments (PLF) detected in the Maryland Forward Array (MFA)

  3. Development of quasi-monochromatic p-7Li neutron generating system for 80-210 MeV

    International Nuclear Information System (INIS)

    Nakao, Noriaki; Shibata, Tokushi; Nakamura, Takashi; Uwamino, Yoshitomo; Nakanishi, Noriyoshi; Kurosawa, Tadahiro; Kim, Unju.

    1996-01-01

    Recently the requirements for the experimental data on the response characteristics of neutron detector and the cross section for neutron generation by charged particles have been increasing for shield designing. Here, a system for quasi-monochromatic neutron generation was developed in the facility of ring-cyclotron in Institute of Physical and Chemical Sciences. In this study, H 2 + accelerated to an energy range of 80-135 MeV/n and P + to 150-210 MeV was irradiated to E4 beam course and NE102A plastic scintillator was used for monitoring the neutron flux. The amount of neutrons generated was estimated from the radioactivity of 7 Be produced in 7 Li-target. The neutron spectres thus estimated as an energy range of 80-210 MeV were presented and the lower limit of these spectres was about 20 MeV. The peaks in the range of 150 and 210 MeV were comparatively wide because of the inferiority of energy resolving power at a higher energy level. (M.N.)

  4. Fusion with projectiles form carbon to argon at energies between 20A and 60A MeV

    International Nuclear Information System (INIS)

    Galin, J.

    1986-03-01

    A review of the linear momentum transfer is made, considering essentially heavy targets and two important parameters in the entrance channel: the projectile energy and its mass. Over a broad mass range, and for energies up to 30A MeV, the momentum transfer scales with the mass of the projectile. At 30A MeV, the most probable value of projectile momentum transferred to the fused system is 80%, and this represents roughly 180 MEV/c per projectile nucleon. At higher bombarding energies, the momentum distribution in the fused systems, as observed from binary fission events, seems to depend on the mass of the projectile. Further studies are still needed to understand this behaviour. Finally, the decay of highly excited (E* approximately 500-800 MeV) fused systems, with masses close to 270 amu, is studied from the characteristics of both fusion fragments and light charged particles. It is shown that thermal equilibrium is reached before fission, even for such high energy deposition. However, the decay sequence is sensitive to dynamical effects and does not depend only on available phase space

  5. Nociceptor-Enriched Genes Required for Normal Thermal Nociception

    Directory of Open Access Journals (Sweden)

    Ken Honjo

    2016-07-01

    Full Text Available Here, we describe a targeted reverse genetic screen for thermal nociception genes in Drosophila larvae. Using laser capture microdissection and microarray analyses of nociceptive and non-nociceptive neurons, we identified 275 nociceptor-enriched genes. We then tested the function of the enriched genes with nociceptor-specific RNAi and thermal nociception assays. Tissue-specific RNAi targeted against 14 genes caused insensitive thermal nociception while targeting of 22 genes caused hypersensitive thermal nociception. Previously uncategorized genes were named for heat resistance (i.e., boilerman, fire dancer, oven mitt, trivet, thawb, and bunker gear or heat sensitivity (firelighter, black match, eucalyptus, primacord, jet fuel, detonator, gasoline, smoke alarm, and jetboil. Insensitive nociception phenotypes were often associated with severely reduced branching of nociceptor neurites and hyperbranched dendrites were seen in two of the hypersensitive cases. Many genes that we identified are conserved in mammals.

  6. Prospects and problems of uranium enrichment

    International Nuclear Information System (INIS)

    Imai, Ryukichi

    1974-01-01

    The problem of uranium enrichment now concerns principally peaceful nuclear power generation. With the current oil crisis, energy resources assume unprecedented importance. However, the requirements for enriched uranium vary with the vicissitude of the world situation in nuclear power generation; the enterprise of uranium enrichment is related to economic aspect. The following matters are described: dimension of enrichment problem, political factors, changes in requirements, projects in each country, and strategy of enrichment in Japan. (Mori, K.)

  7. Uranium enrichment in the United States

    International Nuclear Information System (INIS)

    Hill, J.H.; Parks, J.W.

    1975-01-01

    History, improvement programs, status of electrical power availability, demands for uranium enrichment, operating plan for the U. S. enriching facilities, working inventory of enriched uranium, possible factors affecting deviations in the operating plan, status of gaseous diffusion technology, status of U. S. gas centrifuge advances, transfer of enrichment technology, gaseous diffusion--gas centrifuge comparison, new enrichment capacity, U. S. separative work pricing, and investment in nuclear energy are discussed. (LK)

  8. Optics simulations of the 5 MeV NPBSE FOX telescope

    International Nuclear Information System (INIS)

    Reusch, M.F.; Bruhwiler, D.L.

    1993-01-01

    The far-field optics experiment (FOX) is a proposed design for the neutral particle beam space experiment (NPBSE) program. This 425 MHz straight beam line includes a 4.3 meter large-bore telescope. It is designed to deliver an 8 mA, 5 MeV neutral hydrogen beam with a transverse divergence of approximately 30 micro-radians to a target space vehicle (TSV) located up to 5 km away. The authors present zero current simulations, made with Grummann's TOPKARK code, of the telescope optics and the resulting 5 km target footprint. These simulations demonstrate the need for momentum compactation to minimize chromatic aberrations and for the careful use of octupoles to correct geometric aberrations. TOPKARK uses a novel line dipole model for the large-bore, combined function telescope objective lenses, constructed with rods of permanent magnet material, proposed for use in the FOX. The authors describe this model and its effect on the dynamics

  9. Electromagnetic fission of 238U at 600 and 1000 MeV per nucleon

    International Nuclear Information System (INIS)

    Rubehn, T.; Mueller, W.F.J.; Bassini, R.; Begemann-Blaich, M.; Blaich, T.; Gross, C.; Imme, G.; Iori, I.; Kunde, G.J.; Kunze, W.D.; Lindenstruth, V.; Lynen, U.; Moehlemkamp, T.; Moretto, L.G.; Ocker, B.; Pochodzalla, J.; Raciti, G.; Reito, S.; Sann, H.; Schuettauf, A.; Serfling, V.; Trautmann, W.; Trzcinski, A.; Verde, G.; Woerner, A.; Zude, E.; Zwieglinski, B.

    1995-05-01

    Electromagnetic fission of 238 U projectiles at E/A=600 and 1000 MeV was studied with the ALADIN spectrometer at the heavy-ion synchrotron SIS. Seven different targets (Be, C, Al, Cu, In, Au and U) were used. By considering only those fission events where the two charges added up to 92, most of the nuclear interactions were excluded. The nuclear contributions to the measured fission cross sections were determined by extrapolating from beryllium to the heavier targets with the concept of factorization. The obtained cross sections for electromagnetic fission are well reproduced by extended Weizsaecker-Williams calculations which include E1 and E2 excitations. The asymmetry of the fission fragments' charge distribution gives evidence for the excitation of the double giant-dipole resonance in uranium. (orig.)

  10. Microscopic local optical potentials and the nucleon–nucleus scattering at 65 MeV

    International Nuclear Information System (INIS)

    Haider, W.; Sharma, Manjari

    2010-01-01

    Microscopic local optical potentials from two sources were calculated by folding the numerical g-matrices over point proton and neutron RMF densities of target nuclei. The hard-core Hamada–Johnston and the soft-core Urbana v-14 local inter-nucleon potentials have been used to generate numerical g-matrices by solving Bethe–Goldstone integral equation. The calculated potentials have been used to analyze successfully both the proton and neutron differential elastic scattering and polarization data at 65 MeV over a wide mass region of targets: 12 C– 208 Pb. Comparison of the present results with a phenomenological optical model analyzes is also presented. Mass number dependence of the mean square radii of the two microscopic potentials are in close agreement with each other as well as with empirical results. (author)

  11. Parity nonconservation in the proton-deuteron total cross section at 800 MeV

    International Nuclear Information System (INIS)

    Mischke, R.E.

    1988-01-01

    A measurement of parity nonconservation in the transmission of 800-MeV longitudinally-polarized protons through an unpolarized, one- meter liquid-deuterium target is discussed. The apparatus was essentially that same as for a previous measurement of the effect in p-p scattering. The longitudinal asymmetry is measured from the change in transmission of the beam through the target as the helicity of the beam is reversed. The preliminary result is A/sub L/ = (1.7 +- 0.8(stat) +- 1.0(sys)) /times/ 10/sup /minus/7/. Further study of the dependence of transmission on beam properties should allow the estimate of systematic errors to be reduced and may alter the central value of the result. 11 refs., 2 figs., 1 tab

  12. Supply of enriched uranium for research reactors

    International Nuclear Information System (INIS)

    Mueller, H.

    2004-01-01

    Since the RERTR-Meeting in Newport/USA in 1990 recommended in several papers to the research reactor community to agree upon a worldwide unified technical specification for low enriched uranium (LEU) and high enriched uranium (HEU) in order to facilitate supplies of LEU and HEU to fabricators for acceptance and for fabrication of fresh fuel elements. This target for unified and simplified specification has only been partially reached due to different interests of the fabricators because they want to receive the uranium as pure as possible. As a result of various investigations, however, it became clear that both LEU and HEU received from the United States since the late fifties had different qualities which we have to deal with today due to the availability of stocks. We are now one step forward to know more precisely the properties of LEU and HEU we have received in the past. This uranium was never virgin and we have to cope with this situation. Therefore in my present paper I have concentrated on the documentation of analytical work performed on samples of LEU and HEU received in the past. I propose furthermore a frame of unified specifications for so-called virgin LEU and HEU including uranium from a Zero-experiment. In addition I am giving a recommendation for specifications of LEU obtained by blending of reprocessed HEU. Finally I am touching the question of secure supplies of fresh LEU. (author)

  13. Enriched uranium recovery flowsheet improvements

    International Nuclear Information System (INIS)

    Holt, D.L.

    1986-01-01

    Savannah River uses 7.5% TBP to recover and purify enriched uranium. Adequate decontamination from fission products is necessary to reduce personnel exposure and to ensure that the enriched uranium product meets specifications. Initial decontamination of the enriched uranium from the fission products is carried out in the 1A bank, 16 stages of mixer-settlers. Separation of the enriched uranium from the fission product, 95 Zr, has been adequate, but excessive solvent degradation caused by the long phase contact times in the mixer-settlers has limited the 95 Zr decontamination factor (DF). An experimental program is investigating the replacement of the current 1A bank with either centrifugal contactors or a combination of centrifugal contactors and mixer-settlers. Experimental work completed has compared laboratory-scale centrifugal contactors and mixer-settlers for 95 Zr removal efficiencies. Feed solutions spiked with actual plant solutions were used. The 95 Zr DF was significantly better in the mixer-settlers than in the centrifugal contactors. As a result of this experimental study, a hybrid equipment flowsheet has been proposed for plant use. The hybrid equipment flowsheet combines the advantages of both types of solvent extraction equipment. Centrifugal contactors would be utilized in the extraction and initial scrub sections, followed by additional scrub stages of mixer-settlers

  14. Enrichment plant management and safeguards

    International Nuclear Information System (INIS)

    Hurt, N.H.

    1978-01-01

    The next increment of enrichment at Portsmouth will be gas centrifuge. The safeguards program at Portsmouth is discussed, including the DYMCAS system, the computerization, and the detectors. Control of the material access areas is discussed. The licensee material surveillance and verification program is also described

  15. The changing face of enrichment

    International Nuclear Information System (INIS)

    Dunckel, E.

    1981-01-01

    The AIS techniques considered are atomic vapour laser isotope separation, molecular laser isotope separation and plasma separation. The future of the AIS technique and their advantages over the gas centrifuge method are discussed in terms of economics, power consideration, and possible enrichment contracts. (U.K.)

  16. Environmental Development Plan: uranium enrichment

    International Nuclear Information System (INIS)

    1979-09-01

    This Environmental Development Plan identifies and examines the environmental, health, safety, and socioeconomic concerns and corresponding requirements associated with the DOE research, development, demonstration, and operation of the Uranium Enrichment program, including the gaseous diffusion process, the centrifuge process, centrifuge rotor fabrication, and related research and development activities

  17. Study of the neutron-proton interaction in the 300 to 700 MeV energy region. Annual progress report, 1982-1983

    International Nuclear Information System (INIS)

    Northcliffe, L.C.

    1983-01-01

    Progress by the LAMPF user group from Texas A and M University is described. The principal activities since last year's report have included four months of data taking to complete LAMPF Experiment No. 518 (Polarized Beam and Target Experiments in the p-p System. Phase II. Measurements of A/sub zz/ and A/sub xz/ for the d/sub π/ + Channel and for the Elastic Channel from 500 to 800 MeV) which began running in mid-June 1982. There were also about six weeks of data taking on LAMPF Experiment No. 664 (The Measurement of the Polarization Transfer Coefficients A/sub t/' and D/sub t/ at 500, 650 and 800 MeV for the Reaction d(polarized p, polarized n)2p), and one week of data taking at 800 MeV on LAMPF Experiment No. 590 (Measurement of D(theta) in p-n and n-p Scattering at 800, 650 MeV and Other Energies with Associated p-p Measurements). In addition there were preparations for LAMPF Experiment No. 665 (The Measurement of np Elastic Scattering Spin Correlation Parameters with L- and S-Type Polarized Beam and Target between 500 and 800 MeV) which began running last month and will continue until the end of the year

  18. Recoil properties of antimony isotopes produced by the reaction of 570 MeV and 18.2 GeV protons with uranium

    CERN Document Server

    Hagebø, E

    1969-01-01

    Using the method of thick target and thick catchers, the ranges and other recoil properties of 13 (12) antimony isotopes between A = 115 and A = 131 (130) have been measured for the reaction of 570 MeV (18·2 GeV) protons with uranium. The kinetic energies T are almost independent of product mass number at 570 MeV but show a strong dependence at 18·2 GeV, the lightest isotopes having only about half the kinetic energy of the heavy ones. \\\\ \\\\The cascade deposition energies for production of antimony isotopes are almost equal at 570 MeV and 18·2 GeV and fit well to straight lines of the form E$^{∗}$ (A, Z) = E$^{∗}$ (A$_{0}$, Z) + b(A − A$_{0}$). Exceptions are the cascade deposition energies for $^{115}$Sb and $^{116}$Sb which seem to be somewhat too high at 18·2 GeV. By comparison with other work it seems that the slope $b$ of these lines is independent of product element, target and of proton irradiation energy above 450 MeV. \\\\ \\\\If we assume at 570 MeV, that the fissioning nucleus is a uranium ...

  19. Charge measurement system at 100 MeV linac

    International Nuclear Information System (INIS)

    Li Dongmei; Chinese Academy of Sciences, Beijing; Yin Chongxian; Ye Kairong

    2005-01-01

    A charge measurement system of 100 Mev linac is introduced in this paper. After describing the characteristics and functions of the system's components, the authors analyze the methods of data processing and systematic error in detail. Basing on these, the authors get system resolution in the lab. The actual measurement results are presented at last. (authors)

  20. 3 MeV DC accelerator, EBC Kharghar

    International Nuclear Information System (INIS)

    Bakhtsingh, R.I.; Acharya, S.

    2017-01-01

    The Accelerator and Pulse Power Division (APPD) has designed and developed a 3 MeV, 10 mA DC electron beam accelerator at Electron Beam Centre, Kharghar, Navi Mumbai. This machine has been utilized for reduction of SO_x and NO_x in simulated flue gases and treatment of waste water to reduce COD and BOD

  1. Linac4 crosses the 100 MeV threshold

    CERN Multimedia

    Corinne Pralavorio

    2016-01-01

    The new linear accelerator, which from 2020 will be the first link in the accelerator chain, has entered a new stage of its commissioning.   Members of the team in charge of the commissioning of Linac4 in the accelerator’s control room. A few hours earlier, Linac4 accelerated a beam to 107 MeV for the first time. We couldn’t have imagined a more appropriate date: on 1 July (1.07), Linac4 reached an energy of 107 MeV. Having crossed the 100 MeV barrier, the linear accelerator is now on the home straight of its commissioning. “This stage was very quick – it took less than two weeks,” says Alessandra Lombardi, deputy project leader of Linac4, in charge of the commissioning. In 2020, Linac4 will replace the existing Linac2 as the first link in the accelerator chain. It will accelerate beams of H- ions (protons surrounded by two electrons) to 160 MeV, compared to 50 MeV with Linac2. The new machine is particularly sophisticated as it comprises...

  2. A 30 MeV H- cyclotron for isotope production

    International Nuclear Information System (INIS)

    Milton, B.F.; Dawson, R.; Erdman, K.L.

    1989-05-01

    Because of an expanding market for radioisotopes there is a need for a new generation of cyclotrons designed specifically for this purpose. TRIUMF is cooperating with a local industrial company in designing and constructing such a cyclotron. It will be a four sector H - cyclotron, exploiting the newly developed high brightness multicusp ion source. This source with H - current capability in excess of 5 mA makes feasible accelerated H - beam intensities of up to 500 μA. Beam extraction is by stripping to H + in a thin graphite foil. Extraction of two high-intensity beams, with energy variable from 15 to 30 MeV is planned. The use of an external ion source, provision of a good vacuum in the acceleration region, and the careful choice of materials for components in the median plane leads to a cyclotron that will have low activation and can be easily serviced in spite of the very high operating beam intensities. A design extension to 70 MeV using many of the design features of the 30 MeV cyclotron can be easily made. Such a machine with a good quality variable energy beam is a highly desirable source of protons for isotope production, injection into higher energy high intensity acceleration, injection into higher energy high intensity accelerators, and as an irradiation facility for ocular melanomas. Design of the 30 MeV cyclotron is well advanced and construction is in progress

  3. MEV Energy Electrostatic Accelerator Ion Beam Emittance Measurement

    OpenAIRE

    I.G. Ignat’ev; M.I. Zakharets; S.V. Kolinko; D.P. Shulha

    2014-01-01

    The testing equipment was designed, manufactured and tried out permitting measurements of total current, current profile and emittance of an ion beam extracted from the ion beam. MeV energy electrostatic accelerator ion H + beam emittance measurement results are presented.

  4. Alpha-deuteron elastic scattering around 40 MeV

    International Nuclear Information System (INIS)

    De, A.; Karmakar, S.; Roychaudhury, T.; Dasgupta, S.S.; Chintalapudi, S.N.; Ismail, M.; Banerjee, S.R.; Divatia, A.S.

    1989-01-01

    Differential cross section for alpha-deuteron elastic scattering has been measured at several energies around 40 MeV incident alpha. General behaviour of angular distributions remaining close to that predicted by Faddeev type calculations, a sharp energy dependence is observed. (author). 8 refs

  5. History of the ZGS 500 MeV booster.

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, J.; Martin; R.; Kustom, R.

    2006-05-09

    The history of the design and construction of the Argonne 500 MeV booster proton synchrotron from 1969 to 1982 is described. This accelerator has since been in steady use for the past 25 years to power the Argonne Intense Pulsed Neutron Source (IPNS).

  6. 200 MeV RF linac for synchrotron injection

    International Nuclear Information System (INIS)

    Whitham, K.; Anamkath, H.; Lyons, S.; Manca, J.; Miller, R.; Treas, P.; Zante, T.; Miller, R.

    1992-01-01

    Construction has been completed on an electron linear accelerator for the Brookhaven National Laboratory. This accelerator will be used for the injection of a 200 MeV electron beam into a synchrotron for lithography experiments. This paper describes the conceptual design of the linac, its e-gun pulser, and its control and timing systems. 3 figs., ref

  7. Reduced enrichment program for the FRM-II, status 2004

    International Nuclear Information System (INIS)

    Roehrmoser, A.; Petry, W.; Boening, K; Wieschalla, N.

    2005-01-01

    The new research reactor FRM-II of the Technische Universitaet Muenchen (TUM) has been designed to provide a maximal thermal neutron flux at mere 20 MW power. The single element design uses silicide fuel of densities 3.0 and 1.5 g/cm 3 of highly enriched uranium (HEU, 93 % U-235). With the nuclear license, that was granted in May 2003, a condition was imposed to reduce the enrichment of FRM-II to medium enriched uranium (MEU) with not more than 50 % U-235 until the end of the year 2010. The TUM has established an international working group to meet this target. This paper presents the backgrounds and the results and plannings for the first of three 2 1/2 year periods to reach the conversion in time. (author)

  8. Production of Mo-99 using low-enriched uranium silicide

    International Nuclear Information System (INIS)

    Hutter, J.C.; Srinivasan, B.; Vicek, M.; Vandegrift, G.F.

    1994-01-01

    Over the last several years, uranium silicide fuels have been under development as low-enriched uranium (LEU) targets for Mo-99. The use of LEU silicide is aimed at replacing the UAl x alloy in the highly-enriched uranium dissolution process. A process to recover Mo-99 from low-enriched uranium silicide is being developed at Argonne National Laboratory. The uranium silicide is dissolved in alkaline hydrogen peroxide. Experiments performed to determine the optimum dissolution procedure are discussed, and the results of dissolving a portion of a high-burnup (>40%) U 3 Si 2 miniplate are presented. Future work related to Mo-99 separation and waste disposal are also discussed

  9. Study of the. gamma. rho. -->. n. pi. /sup +/ reaction with polarized protons and photons at E/sub. gamma. /=340 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Get' man, V.A.; Gorbenko, V.G.; Grushin, V.F.; Derkach, A.Y.; Zhebrovskii, Y.V.; Karnaukhov, I.M.; Kolesnikov, L.Y.; Lukhanin, A.A.; Rubashkin, A.L.; Sanin, V.M.; Sorokin, P.V.; Sporov, E.A.; Telegin, Y.N.

    1979-07-05

    A two-fold polarization experiment of the ''beam-target'' type is carried out for the first time for the reaction ..gamma..p..-->..n..pi../sup +/ for E/sub ..gamma../ =340 MeV, and the three polarization parameters, ..sigma.., T, and P are determined simultaneously.

  10. Escaping 1 MeV tritons in TFTR

    International Nuclear Information System (INIS)

    Zweben, S.J.; Strachan, J.D.; Boivin, R.; Cavallo, A.; Fredrickson, E.D.; McGuire, K.; Mynick, H.E.; White, R.B.

    1989-01-01

    1 MeV tritons created by D-D reactions can simulate the 'single-particle' behavior expected with 3.5 MeV D-T alphas, since the gyroradii and slowing-down of these two particles are similar. This paper describes measurements of the flux of escaping 1 MeV tritons from the TFTR plasma during high power D 0 →D neutral beam injection, and shows that in most cases the observed triton loss is consistent with the classical (single-particle) first-orbit loss model. In this model tritons are lost if their first orbit intersects the wall due to their large banana width, while almost all tritons confined on their first orbit should stay confined until thermalized. The triton detectors are ZnS(Ag) scintillator screens housed in light-tight boxes located just outside the plasma boundary at the bottom of the TFTR vessel. They are particle 'pinhole' cameras which can resolve the triton flux vs. pitch angle (to ±5 o ), energy (to ±50 %), and time (to <20 μsec). The 2-D images of triton flux onto these scintillators are optically coupled to either an intensified TV camera or to photomultiplyer tubes for fast time resolution. The soft x-ray background in an earlier prototype has been eliminated. Although there are presently 8 such detectors in TFTR, this paper discusses results from only the detector located just below the vessel center (R=259 cm, r=102 cm). Note that the '1 MeV triton' signal discussed below also has about a 30 % contribution from 3 MeV protons; however, since these two particles have identical gyroradii they should behave alike. 5 refs., 5 figs

  11. The Fermilab 400-MeV Linac Upgrade

    International Nuclear Information System (INIS)

    Schmidt, C.W.

    1993-05-01

    The Fermilab Linac Upgrade will increase the linac energy from 201 MeV to 401.5 MeV. Seven accelerating modules, composed of 805-MHz side-coupled cells, will accelerate H - beams from 116.5 to 401.5 MeV. The side-coupled structure (SCS) has been built, tuned, tested to full power, and placed in the linac enclosure along side the operating Linac. All seven accelerating modules, each containing four sections of sixteen cells, have been connected to 12-MW power klystrons and tested to full power for a significant period. The transition section to match the beam from the 201.25-MHz drift-tube linac to the SCS, consisting of a sixteen-cell cavity and a vernier four-cell cavity, has also been tested at full power. A new import line from the Linac to the Booster synchrotron with a new Booster injection girder is to be installed. Removal of the last four Alvarez linac tanks (116.5 to 201 MeV) and beam-line installation of the Upgrade components is to begin in early June 1993 and should take about 12 weeks. Beam commissioning of the project will follow and normal operation is expected in a short period. In preparation for beam commissioning, studies are being done with done operating linac to characterize the beam at transition and prepare for phase, amplitude and energy measurements to commission the new linac. The past, present and future activities of the 400-MeV Upgrade will be reviewed

  12. Evaluation of Methyl-Binding Domain Based Enrichment Approaches Revisited.

    Directory of Open Access Journals (Sweden)

    Karolina A Aberg

    Full Text Available Methyl-binding domain (MBD enrichment followed by deep sequencing (MBD-seq, is a robust and cost efficient approach for methylome-wide association studies (MWAS. MBD-seq has been demonstrated to be capable of identifying differentially methylated regions, detecting previously reported robust associations and producing findings that replicate with other technologies such as targeted pyrosequencing of bisulfite converted DNA. There are several kits commercially available that can be used for MBD enrichment. Our previous work has involved MethylMiner (Life Technologies, Foster City, CA, USA that we chose after careful investigation of its properties. However, in a recent evaluation of five commercially available MBD-enrichment kits the performance of the MethylMiner was deemed poor. Given our positive experience with MethylMiner, we were surprised by this report. In an attempt to reproduce these findings we here have performed a direct comparison of MethylMiner with MethylCap (Diagenode Inc, Denville, NJ, USA, the best performing kit in that study. We find that both MethylMiner and MethylCap are two well performing MBD-enrichment kits. However, MethylMiner shows somewhat better enrichment efficiency and lower levels of background "noise". In addition, for the purpose of MWAS where we want to investigate the majority of CpGs, we find MethylMiner to be superior as it allows tailoring the enrichment to the regions where most CpGs are located. Using targeted bisulfite sequencing we confirmed that sites where methylation was detected by either MethylMiner or by MethylCap indeed were methylated.

  13. Neutron-neutron quasifree scattering in nd breakup at 10 MeV

    Science.gov (United States)

    Malone, R. C.; Crowe, B.; Crowell, A. S.; Cumberbatch, L. C.; Esterline, J. H.; Fallin, B. A.; Friesen, F. Q. L.; Han, Z.; Howell, C. R.; Markoff, D.; Ticehurst, D.; Tornow, W.; Witała, H.

    2016-03-01

    The neutron-deuteron (nd) breakup reaction provides a rich environment for testing theoretical models of the neutron-neutron (nn) interaction. Current theoretical predictions based on rigorous ab-initio calculations agree well with most experimental data for this system, but there remain a few notable discrepancies. The cross section for nn quasifree (QFS) scattering is one such anomaly. Two recent experiments reported cross sections for this particular nd breakup configuration that exceed theoretical calculations by almost 20% at incident neutron energies of 26 and 25 MeV [1, 2]. The theoretical values can be brought into agreement with these results by increasing the strength of the 1S0 nn potential matrix element by roughly 10%. However, this modification of the nn effective range parameter and/or the 1S0 scattering length causes substantial charge-symmetry breaking in the nucleon-nucleon force and suggests the possibility of a weakly bound di-neutron state [3]. We are conducting new measurements of the cross section for nn QFS in nd breakup. The measurements are performed at incident neutron beam energies below 20 MeV. The neutron beam is produced via the 2H(d, n)3He reaction. The target is a deuterated plastic cylinder. Our measurements utilize time-of-flight techniques with a pulsed neutron beam and detection of the two emitted neutrons in coincidence. A description of our initial measurements at 10 MeV for a single scattering angle will be presented along with preliminary results. Also, plans for measurements at other energies with broad angular coverage will be discussed.

  14. Elastic neutron scattering studies at 96 MeV for transmutation.

    Science.gov (United States)

    Osterlund, M; Blomgren, J; Hayashi, M; Mermod, P; Nilsson, L; Pomp, S; Ohrn, A; Prokofiev, A V; Tippawan, U

    2007-01-01

    Elastic neutron scattering from (12)C, (14)N, (16)O, (28)Si, (40)Ca, (56)Fe, (89)Y and (208)Pb has been studied at 96 MeV in the10-70 degrees interval, using the SCANDAL (SCAttered Nucleon Detection AssembLy) facility. The results for (12)C and (208)Pb have recently been published, while the data on the other nuclei are under analysis. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. A novel method for normalisation of the absolute scale of the cross section has been used. The estimated normalisation uncertainty, 3%, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. Elastic neutron scattering is of utmost importance for a vast number of applications. Besides its fundamental importance as a laboratory for tests of isospin dependence in the nucleon-nucleon, and nucleon-nucleus, interaction, knowledge of the optical potentials derived from elastic scattering come into play in virtually every application where a detailed understanding of nuclear processes is important. Applications for these measurements are dose effects due to fast neutrons, including fast neutron therapy, as well as nuclear waste incineration and single event upsets in electronics. The results at light nuclei of medical relevance ((12)C, (14)N and (16)O) are presented separately. In the present contribution, results on the heavier nuclei are presented, among which several are of relevance to shielding of fast neutrons.

  15. Parity violation in polarized p-p scattering at 222 MEV

    International Nuclear Information System (INIS)

    Bandyopadhyay, D.; Birchall, J.; Campbell, J.; Davis, C.A.; Davison, N.E.; Page, S.A.; Ramsay, W.D.; Sekulovich, A.M.; Oers, W.T.H. van; Davis, C.A.; Healey, D.C.; Schmor, P.W.; Stinson, G.M.; Boyce, M.; Green, P.W.; Korkmaz, E.; Soukup, J.; Bowman, J.D.; Mischke, R.E.

    1989-01-01

    An experiment is in progess at TRIUMF to measure the parity-violating longitudinal analyzing power A z in polarizedp-p scattering at 222 MeV. Previous measurements at 15 and 45 MeV have determined the parity-mixed partial wave scattering amplitude to high precision. In contrast, only the ( 3 P 2 - 1 D 2 ) amplitude contributes to A z at 222 MeV. These two amplitudes yield complementary information on the underlying parity violating reaction mechanism. In a weak meson exchange model, the ( 3 P 2 - 1 D 2 ) amplitude is entirely due to rho meson exchange, and the present experiment affords a unique opportunity to measure the weak ρ-N coupling strength h ρ . At TRIUMF, a 500 nA beam of longitudinally polarized protons (p z ∼0.8) from the optically pumped polarized ion source will be scattered from a 20 cm liquid hydrogen target. A unique feature of this experiment is that A z will be measured in two different geometries (scattering and transmission mode) simultaneously, which will provide a crucial consistency check on the results. Monte Carlo simulations have confirmed that d.c. ionization chambers used to collect the transmitted and scattered protons in the two simultaneous measurements will achieve comparable statistical accuracies in the ∼ 300 hour counting time proposed for the experiment. High precision monitoring devices are being constructed and tested at TRIUMF to monitor changes in beam properties, such as beam position and residual transverse polarization, that can contribute to systematic errors in the parity violation measurements. The present status of the detector developments and systematic error controls will be discussed

  16. Neutron-capture cross-section measurements of 74Ge and 76Ge in the energy region 0.4-14.8 MeV for neutrinoless double β decay applications

    Science.gov (United States)

    Bhike, Megha; Tornow, Werner

    2013-10-01

    Fast neutron capture cross sections for the reactions 74Ge(n, γ)75Ge and 76Ge(n, γ)77Ge have been measured in the neutron energy region 0.4-14.8 MeV with the activation method. The results are important to identify backgrounds in the neutrinoless double- β decay experiments GERDA and MAJORANA, which use germanium as both source and detector. Isotopically enriched targets which consisted of 86% of 76Ge and 14% of 74Ge were irradiated with mono-energetic neutrons produced via 3H(p,n)3He, 2H(d,n)3He and 3H(d,n)4He reactions. The cross sections were determined relative to 197Au(n, γ)198Au, 115In(n,n')115mIn and 197Au(n,2n)196Au standard cross sections. The activities of the products were measured using high-resolution γ-ray spctroscopy. The present results are compared with the evaluated data from ENDF/B-VII.1 and TALYS.

  17. The commercial role for centrifuge enrichment

    International Nuclear Information System (INIS)

    Readle, P.H.; Wilcox, P.

    1987-01-01

    The enrichment market is extremely competitive and capacity greatly exceeds demand. BNFL [British Nuclear Fuels Ltd.] is in a unique position in having commercial experience of the two enrichment technologies currently used industrially: diffusion, and centrifuge enrichment through its associate company Urenco. In addition, BNFL is developing laser enrichment techniques as part of a UK development programme. The paper describes the enrichment market, briefly discusses the relative merits of the various methods of uranium enrichment and concludes that the gas centrifuge will be best able to respond to market needs for at least the remainder of the century. (author)

  18. Enrichment into the 21st century

    International Nuclear Information System (INIS)

    Rutkowski, E.

    1995-01-01

    This article discusses the future of the enrichment services market into the next century. It is estimated that demand for enrichment services will reach 31 million SWU by the end of the century and remain constant for the following 10 years. The current world enrichment capacity is 44 million SWU, or some 50% ahead of the demand. This oversupply is projected to continue into the next century, but in spite of this, several suppliers are planning new enrichment facilities. HEU as a source of enriched uranium is examined. Overall, long-term prices for enrichment services are expected to decline in the coming decade

  19. Cross sections measurements for the forward elastic scattering of 13 MeV 6,7 Li and 24 MeV 16 O by 9 Be, 12 C, 16 O and 28 Si

    International Nuclear Information System (INIS)

    Liendo, J.A.; Gonzalez, A.C.; Fletcher, N.R.; Caussyn, D.D.

    2001-01-01

    Full text: Absolute elastic cross sections have been measured for targets of 9 Be, 12 C 16 O, 28 Si and 197 Au being bombarded by beams of 13 MeV 6 7 Li and 24 MeV 16 O. The relevant yields were collected simultaneously at 12.450, 16.450, 20.450 and 280. The confidence of a forward elastic scattering method proposed previously to carry out multi-elemental analysis of evaporated liquid samples depends on the precision and accuracy of the cross sections reported in this work.The 24 MeV 16 0 + 197 Au reaction was used to determine the detector solid angles with uncertainties of approximately 3%. Some of the 16 O-beam reactions Some of the 16 O beam reactions have been shown to be consistent with the Rutherford formula predictions at several angles. This allowed us to obtain target thickness independent cross sections for the lithium beam initiated reactions with uncertainties close to 7%. In general, the 6 7 Li-beam reaction cross sections were found not to be consistent with the Coulomb scattering formula. In order to test the internal consistency of our measured cross sections, they were used to determine the elemental densities of several selected targets containing beryllium, carbon, oxygen and silicon. These targets were bombarded with the same beam types and energies used to measure the cross sections and, for every element of interest contained in each target, elemental density values were obtained at some of the scattering angles quoted above. Agreements between some of our results and those of a previous work support the validity of our measurements. (Author)

  20. Scintillating-fiber imaging detector for 14-MeV neutrons

    International Nuclear Information System (INIS)

    Ress, D.; Lerche, R.A.; Ellis, R.J.; Heaton, G.W.; Nelson, M.B.; Mant, G.; Lehr, D.E.

    1994-01-01

    The authors have created a detector to image the neutrons emitted by imploded inertial-confinement fusion targets. The 14-MeV neutrons, which are produced by deuterium-tritium fusion events in the target, pass through an aperture to create an image on the detector. The neutron radiation is converted to blue light (430 nm) with a 20-cm-square array of plastic scintillating fibers. Each fiber is 10-cm long with a 1-mm-square cross section; approximately 35-thousand fibers make up the array. The resulting blue-light image is reduced and amplified by a sequence of fiber-optic tapers and image intensifiers, then acquired by a CCD camera. The fiber-optic readout system was tested optically for overall throughput the resolution. The authors plan to characterize the scintillator array reusing an ion-beam neutron source as well as DT-fusion neutrons emitted by inertial confinement targets. Characterization experiments will measure the light-production efficiency, spatial resolution, and neutron scattering within the detector. Several neutron images of laser-fusion targets have been obtained with the detector. Several neutron images of laser-fusion targets have been obtained with the detector. They describe the detector and their characterization methods, present characterization results, and give examples of the neutron images

  1. Measured neutron carbon kerma factors from 14.1 MeV to 18 MeV

    International Nuclear Information System (INIS)

    Deluca, P.M.; Barschall, H.H.; McDonald, J.C.

    1985-01-01

    For A-150 tissue-equivalent plastic, the total neutron kerma is dominated by the hydrogen kerma. Tissue kerma is inferred with reasonable accuracy by normalization to the kerma factor ratio between tissue and A-150 plastic. Because of the close match in the hydrogen abundance in these materials, the principal uncertainty is due to the kerma factors of carbon and oxygen. We have measured carbon kerma factor values of 0.183+-0.015 10 -8 cGy cm 2 and 0.210+-0.016 10 -8 cGy cm 2 at 14.1-MeV and 15-MeV neutron energy, respectively. A preliminary value of 0.297+-0.03 10 -8 cGy cm 2 has been determined at 17.9 MeV. A recent microscopic cross section measurement of the (n,n'3α) reaction in carbon at 14.1-MeV energy gives a kerma factor of 0.184+-0.019 10 -8 cGy cm 2 in agreement with the present result

  2. Measured neutron carbon kerma factors from 14.1 MeV to 18 MeV

    International Nuclear Information System (INIS)

    Deluca, P.M. Jr.; Barschall, H.H.; Haight, R.C.; McDonald, J.C.

    1984-01-01

    For A-150 tissue-equivalent plastic, the total neutron kerma is dominated by the hydrogen kerma. Tissue kerma is inferred with reasonable accuracy by normalization to the kerma factor ratio between tissue and A-150 plastic. Because of the close match in the hydrogen abundance in these materials, the principal uncertainty is due to the kerma factors of carbon and oxygen. We have measured carbon kerma factor values of 0.183 +- 0.015 10 -8 cGy cm 2 and 0.210 +- 0.16 10 -8 cGy cm 2 at 14.1-MeV and 15-MeV neutron energy, respectively. A preliminary value of 0.297 +- 0.03 10 -8 cGy cm 2 has been determined at 17.9 MeV. A recent microscopic cross section measurement of the (n,n'3α) reaction in carbon at 14.1-MeV energy gives a kerma factor of 0.184 +- 0.019 10 8 cGy cm 2 in agreement with the present result. 9 refs., 4 figs., 2 tabs

  3. Extension of the calibration of an NE-213 liquid scintillator based pulse height response spectrometer up to 18 MeV neutron energy and leakage spectrum measurements on bismuth at 8 MeV and 18 MeV neutron energies

    International Nuclear Information System (INIS)

    Fenyvesi, A.; Valastyan, I.; Olah, L.; Csikai, J.; Plompen, A.; Jaime, R.; Loevestam, G.; Semkova, V.

    2011-01-01

    Monoenergetic neutrons were produced at the Van de Graaff accelerator of the EC-JRC-Institute for Reference Materials and Measurements (IRMM, Geel, Belgium). An air-jet cooled D_2-gas target (1.2 bar, ΔE_d = 448 keV) was bombarded with E_d =4976 keV deuterons to produce neutrons up to E_n = 8 MeV energy via the D(d,n)"3He reaction. Higher energy neutrons up to E_n = 18 MeV were produced via the T(d,n)"4He reaction by bombarding a TiT target with E_d =1968 keV deuterons. Pulse height spectra were measured at different neutron energies from E_n = 8 MeV up to E_n = 18 MeV with the NE-213 liquid scintillator based Pulse Height Response Spectrometer (PHRS) of UD-IEP. The energy calibration of the PHRS system has been extended up to E_n = 18 MeV. Pulse height spectra induced by gamma photons have been simulated by the GRESP7 code. Neutron induced pulse height spectra have been simulated by the NRESP7 and MCNP-POLIMI codes. Comparison of the results of measurements and simulations enables the improvement of the parameter set of the function used by us to describe the light output dependence of the resolution of the PHRS system at light outputs of L > 2 light units. Also, it has been shown that the derivation method for unfolding neutron spectra from measured pulse height spectra performs well when relative measurements are done up to E_n = 18 MeV neutron energy. For matrix unfolding purposes, the NRESP7 code has to be preferred to calculate the pulse height response matrix of the PHRS system. Leakage spectra of neutrons behind bismuth slabs of different thicknesses have been measured with the PHRS system by using monoenergetic neutrons. The maximum slab thickness was d = 14 cm. Simulations of the measurements have been carried out with the MCNP-4c code. The necessary nuclear cross-sections were taken from the from the ENDF/B-VII and JEFF.3.1 data libraries. For both libraries, the agreement of measured and simulated neutron spectra is good for the 5 MeV ≤ En ≤ 18 MeV

  4. Elastic and inelastic scattering of α particles at 41MeV and elastic scattering of 3He at 46MeV on 27Al, 28Si, 29Si, and 30Si

    International Nuclear Information System (INIS)

    Mariolopoulos, Georges.

    1976-01-01

    Elastic and inelastic scattering of α particles at 41MeV has been studied on 27 Al, 28 Si, 29 Si and 30 Si between 30 and 160deg c.m. The elastic cross section for α particles on 28 Si shows more oscillation than that for the other targets in the region between 80 and 160deg c.m. The data have been analyzed using both a 9 parameters optical model potential and a coupled channel code. In order to investigate the assumption that the abnormal cross section of 28 Si is due to a cluster effect, the 27 Al, 28 Si, 29 Si, 30 Si( 3 He, 3 He) reaction have been studied between 30 and 110deg c.m., using a 46MeV beam. In this case the angular distributions of the three Si isotopes are similar. An optical model analysis of the data reveals no anomaly [fr

  5. Enrichment demand boosts SWU prices

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The enrichment market is picking up significantly on very brisk demand. US utilities, which normally purchase material nine months to a year ahead of time, are already hitting the market to fill their 1996 requirements. In June, two non-US utilities, one European entity and a US utility bought SWUs, the entity in an off-market deal. But that doesn't tell the whole story. Three other US utilities entered the market during the month. Meanwhile, we count 13 more utilities getting ready to hit the market for more than 4 million SWUs. Why the surge in demand? Utilities, uncertain of the role to be played by the new US Enrichment Corp. and seeking to take advantage of low interest rates, are implementing buy and hold strategies. As a result, the upper end of NUKEM's SWU price range inched up to $78. The lower end dipped to $67 based on the European deal

  6. Enrichment techniques employed in phosphoproteomics

    Czech Academy of Sciences Publication Activity Database

    Fíla, Jan; Honys, David

    2012-01-01

    Roč. 43, č. 3 (2012), s. 1025-1047 ISSN 0939-4451 R&D Projects: GA ČR(CZ) GAP501/11/1462; GA ČR GA522/09/0858; GA ČR GA525/09/0994; GA MŠk OC08011 Institutional research plan: CEZ:AV0Z50380511 Keywords : Phosphoproteomics * Enrichment * IMAC Subject RIV: ED - Physiology Impact factor: 3.914, year: 2012

  7. Uranium enrichment plans and policies

    International Nuclear Information System (INIS)

    Schwennesen, J.L.

    1981-01-01

    Significant progress has been made in US efforts to expand its enrichment capacity. The Cascade Improvement Program (CIP) and Cascade Upgrading Program (CUP) are now complete at Oak Ridge and Paducah and almost complete at Portsmouth. Considerable progress has also been made in constructing the Gas Centrifuge Enrichment Plant (GCEP), and physical construction of the first process building is well under way. Current plans are to have two process buildings on-line by 1989 with the remaining six buildings to be added sequentially as needed to meet demand. The status of DOE enrichment services contracts is essentially unchanged from that reported at last year's seminar. The OUEA latest forecast of nuclear power growth, however, is considerably lower than reported last year, although a leveling trend is becoming apparent. The Variable Tails Assay Option (VTAO) of the AFC contract was made available for the third time for FY 1983. The DOE inventories of natural uranium still remain high. The Department of Energy will dispose of this material by using it for Government programs and for enrichment plant operations. It appears that Government inventories of uranium are adequate through at least the mid-1990s. It remains DOE policy not to dispose of its natural uranium stocks through direct sales in the marketplace, except for very small quantities or if an emergency situation would exist and all reasonable attempts had been made, without success, to obtain natural uranium from commercial sources. Finally, with regard to DOE plans on future transaction tails assays, it still appears likely that the current 0.20 percent uranium-235 reference tails assay will be maintained until well into the 1990s, at which time it might be increased up to 0.25 percent uranium-235

  8. Fission cross section and fission fragment angular distribution for oriented nucleus fission by intermediate energy neutrons (epsilon < or approximately 1 Mev)

    International Nuclear Information System (INIS)

    Barabanov, A.L.; Grechukhin, D.P.

    1985-01-01

    General analysis is conducted, and formulae for fission cross section and angular distribution of fission fragments of oriented nuclei by fast neutrons are presented. Geometrical coefficients making up the formulae permitting to carry out calculations for target nuclei with spins I=3/2, 5/2, 7/2 at interaction energies epsilon < or approximately 1 MeV are tabulated. Results of demonstrative calculation of fission fragment angular distribution of oriented sup(235)U nuclei by 0.1 <= epsilon <= 1.0 MeV neutrons reveal that angular distribution weakly depends on the set of permeability factors of neutron waves applied in the calculations

  9. Study of the reaction D(p,π+)T at T/sub p/ = 410, 605, and 809 MeV

    International Nuclear Information System (INIS)

    Aslanides, E.; Bertini, R.; Bing, O.; Brochard, F.; Gorodetzky, P.; Hibou, F.; Bauer, T.S.; Beurtey, R.; Boudard, A.; Bruge, G.; Catz, H.; Chaumeaux, A.; Couvert, P.; Duhm, H.H.; Garreta, D.; Igo, G.; Lugol, J.C.; Matoba, M.; Terrien, Y.; Bimbot, L.; Le Bornec, Y.; Tatischeff, B.

    1977-01-01

    Pion production on a CD 2 target has been measured using the high-resolution magnetic spectrometer SPES I. Differential cross section for the reaction D(p,π + )T have been determined at T/sub p/ = 410, 605, and 809 MeV. The present data, together with previous results establish a complete angular distribution of the reaction D(p,π + )T at approx. 600 MeV and energy dependence of the differential cross section for this reaction at several constant momentum transfers

  10. Measurements of neutron emission spectra and 7Be production in Li(d, n) and Be(d, n) reactions for 25 and 40 MeV deuterons

    International Nuclear Information System (INIS)

    Hagiwara, Masayuki; Baba, Mamoru; Aoki, Takao; Kawata, Naoki; Hirabayashi, Naoya; Itoga, Toshiro

    2003-01-01

    The neutron spectra in Li(d, n) and Be(d, n) reactions for Ed = 25, 40 MeV were measured from ∼1 MeV to highest energy of secondary neutrons at ten laboratory angles between 0- and 110-deg with the time-of-flight (TOF) method. In addition, the number of 7 Be accumulated in the targets was also measured by counting the γ-rays from 7 Be using a pure Ge detector to obtain 7 Be production cross-section and yields. (author)

  11. Selenium Enrichment of Horticultural Crops.

    Science.gov (United States)

    Puccinelli, Martina; Malorgio, Fernando; Pezzarossa, Beatrice

    2017-06-04

    The ability of some crops to accumulate selenium (Se) is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

  12. Selenium Enrichment of Horticultural Crops

    Directory of Open Access Journals (Sweden)

    Martina Puccinelli

    2017-06-01

    Full Text Available The ability of some crops to accumulate selenium (Se is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

  13. Observation of enhanced zero-degree binary encounter electron production with decreasing charge-state q in 30 MeV Oq+ + O2 collisions

    International Nuclear Information System (INIS)

    Zouros, T.J.M.; Wong, K.L.; Hidmi, H.I.

    1993-01-01

    We have measured binary encounter electron production in collisions of 30 MeV O q+ projectiles (q=4-8) and O 2 targets. Measured double differential BEe cross-sections are found to increase with decreasing charge-state q, in agreement with similar previously reported zero-degree investigations for H 2 and He targets. However, measurements for the same system but at 25 degrees shows the opposite trend, that BEe cross sections decrease slightly with decreasing charge state

  14. Comparison of biological and genomic characteristics between a newly isolated mink enteritis parvovirus MEV-LHV and an attenuated strain MEV-L.

    Science.gov (United States)

    Mao, Yaping; Wang, Jigui; Hou, Qiang; Xi, Ji; Zhang, Xiaomei; Bian, Dawei; Yu, Yongle; Wang, Xi; Liu, Weiquan

    2016-06-01

    A virus isolated from mink showing clinical signs of enteritis was identified as a high virulent mink enteritis parvovirus (MEV) based on its biological characteristics in vivo and in vitro. Mink, challenged with this strain named MEV-LHV, exhibited severe pathological lesions as compared to those challenged with attenuated strain MEV-L. MEV-LHV also showed higher infection and replication efficiencies in vitro than MEV-L. Sequence of the complete genome of MEV-LHV was determined and analyzed in comparison with those in GenBank, which revealed that MEV-LHV shared high homology with virulent strain MEV SD12/01, whereas MEV-L was closely related to Abashiri and vaccine strain MEVB, and belonged to a different branch of the phylogenetic tree. The genomes of the two strains differed by insertions and deletions in their palindromic termini and specific unique mutations (especially VP2 300) in coding sequences which may be involved in viral replication and pathogenicity. The results of this study provide a better understanding of the biological and genomic characteristics of MEV and identify certain regions and sites that may be involved in viral replication and pathogenicity.

  15. High resolution inelastic gamma-ray measurements with a white neutron source from 1 to 200 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, R.O.; Laymon, C.M.; Wender, S.A.

    1990-01-01

    Measurements of prompt gamma rays following neutron-induced reactions have recently been made at the spallation neutron source at the WNR target area of LAMPF using germanium detectors. These experiments provide extensive excitation function data for inelastic neutron scattering as well as for other reactions such as (n,{alpha}), (n,n{alpha}), (n,p), (n,np), (n,nnp) and (n,xn) for 1 {le} {times} {le} 11. The continuous energy coverage available from 1 MeV to over 200 MeV is ideal for excitation function measurements and greatly extends the energy range for such data. The results of these measurements will provide a database for interpretation of gamma-ray spectra from the planned Mars Observer mission, aid in radiation transport calculations, allow verification of nuclear reaction models, and improve the evaluated neutron reaction data base.

  16. High resolution inelastic gamma-ray measurements with a white neutron source from 1 to 200 MeV

    International Nuclear Information System (INIS)

    Nelson, R.O.; Laymon, C.M.; Wender, S.A.

    1990-01-01

    Measurements of prompt gamma rays following neutron-induced reactions have recently been made at the spallation neutron source at the WNR target area of LAMPF using germanium detectors. These experiments provide extensive excitation function data for inelastic neutron scattering as well as for other reactions such as (n,α), (n,nα), (n,p), (n,np), (n,nnp) and (n,xn) for 1 ≤ x ≤ 11. The continuous energy coverage available from 1 MeV to over 200 MeV is ideal for excitation function measurements and greatly extends the energy range for such data. The results of these measurements will provide a database for interpretation of gamma-ray spectra from the planned Mars Observer mission, aid in radiation transport calculations, allow verification of nuclear reaction models, and improve the evaluated neutron reaction data base

  17. Proton spectra from 800 MeV protons on selected nuclei. Progress report, January 1, 1979-December 31, 1979

    International Nuclear Information System (INIS)

    Stearns, R.L.

    1979-09-01

    The emission of protons from targets of 6 Li, Li, 12 C, 27 Al, 40 Ca, 51 V, 90 Zr, and Pb under bombardment from 800 MeV protons was studied using the high resolution proton spectrometer at the Los Alamos Meson Physics Facility. Laboratory scattering angles of 5, 7, 9, 11, 13, 15, 20, 25, and 30 0 were measured, with special emphasis on the quasi-free region. Outgoing momenta corresponding to the region of pion production were examined at 11 and 15 0 . Absolute cross sections derived by reference to known (p,p) scattering data at 800 MeV. The quasi-free scattering has been fit with a DWIA analysis by summing over the unobserved (struck) nucleon. The systematics of proton production and the applicability of the DWIA analyses are discussed. 26 references

  18. The local distribution of radiation quality of a collimated fast neutron beam from 15 MeV deuterons on beryllium

    International Nuclear Information System (INIS)

    Fidorra, J.; Booz, J.

    1978-01-01

    The local distribution of radiation quality (ysub(F), ysub(D)) of a collimated fast neutron beam from 14 MeV deuterons on Beryllium was studied with a spherical 1/2 inch EG and G proportional counter simulating a diameter of 2μm. The deuterons were accelerated by the compact cyclotron CV-28 of the Kernforschungsanlage Juelich. The collimator was constructed by the Cyclotron Corporation. The mean neutron energy was 6 MeV. The measurements were performed in air and in a water phantom at a target skin distance of 125 cm. The energy deposition spectra of fast neutrons obtained at various positions were separated into three components of different radiation quality: the gamma component, the recoil proton component, and the heavy ion component

  19. Absolute differential cross sections for π±p elastic scattering at 30 ≤ Tπ ≤ 67 MeV

    International Nuclear Information System (INIS)

    Brack, J.T.; Ristinen, R.A.; Kraushaar, J.J.

    1989-11-01

    Absolute π±p differential cross sections have been measured at incident pion energies of 30.0, 45.0, and 66.8 MeV, using active targets of scintillator plastic (CH 1.1 ) to detect recoil protons in coincidence with scattered pions. Statistical uncertainties are typically ±3%; systematic uncertainties are ±2%. The results are consistent with two earlier measurements by this group employing different experimental techniques at 67 MeV and higher incident pion energies. The π - p cross sections are in good agreement with currently accepted phase-shift analyses, but the corresponding π + p predictions are typically 15% higher at large angles than the π + p data reported here

  20. Preliminary conceptual design for a 510 MeV electron/positron injector for a UCLA φ factory

    International Nuclear Information System (INIS)

    Dahlbacka, G.; Hartline, R.; Barletta, W.; Pellegrini, C.

    1991-01-01

    UCLA is proposing a compact suer conducting high luminosity (10 32-33 cm -2 sec -1 ) e + e - collider for a φ factory. To achieve the required e + e - currents, full energy injections from a linac with intermediate storage in a Positron Accumulator Ring (PAR) is used. The elements of the linac are outlined with cost and future flexibility in mind. The preliminary conceptual design starts with a high current gun similar in design to those developed at SLAC and at ANL (for the APS). Four 4-section linac modules follow, each driven by a 60 MW klystron with a 1 μsec macropulse and an average current of 8.6 A. The first 4-section model is used to create positrons in a tungsten target at 186 MeV. The three remaining three modules are used to accelerate the e + e - beam to 558 MeV (no load limit) for injection into the PAR