Constraints on Leptophilic Dark Matter from the AMS-02 Experiment

International Nuclear Information System (INIS)

Cavasonza, Leila Ali; Gast, Henning; Schael, Stefan; Krämer, Michael; Pellen, Mathieu

2017-01-01

The annihilation of dark matter particles in the Galactic halo of the Milky Way may lead to cosmic ray signatures that can be probed by the AMS-02 experiment, which has measured the composition and fluxes of charged cosmic rays with unprecedented precision. Given the absence of characteristic spectral features in the electron and positron fluxes measured by AMS-02, we derive upper limits on the dark matter annihilation cross section for leptophilic dark matter models. Our limits are based on a new background model that describes all recent measurements of the energy spectra of cosmic-ray positrons and electrons. For thermal dark matter relics, we can exclude dark matter masses below about 100 GeV. We include the radiation of electroweak gauge bosons in the dark matter annihilation process and compute the antiproton signal that can be expected within leptophilic dark matter models.

Constraints on Leptophilic Dark Matter from the AMS-02 Experiment

Energy Technology Data Exchange (ETDEWEB)

Cavasonza, Leila Ali; Gast, Henning; Schael, Stefan [I. Physikalisches Institut, RWTH Aachen University, D-52074 Aachen (Germany); Krämer, Michael [Institute for Theoretical Particle Physics and Cosmology, RWTH Aachen University, D-52074 Aachen (Germany); Pellen, Mathieu, E-mail: cavasonza@physik.rwth-aachen.de [Institut für Theoretische Physik und Astrophysik, Universität Würzburg, D-97074 Würzburg (Germany)

2017-04-10

The annihilation of dark matter particles in the Galactic halo of the Milky Way may lead to cosmic ray signatures that can be probed by the AMS-02 experiment, which has measured the composition and fluxes of charged cosmic rays with unprecedented precision. Given the absence of characteristic spectral features in the electron and positron fluxes measured by AMS-02, we derive upper limits on the dark matter annihilation cross section for leptophilic dark matter models. Our limits are based on a new background model that describes all recent measurements of the energy spectra of cosmic-ray positrons and electrons. For thermal dark matter relics, we can exclude dark matter masses below about 100 GeV. We include the radiation of electroweak gauge bosons in the dark matter annihilation process and compute the antiproton signal that can be expected within leptophilic dark matter models.

Prototype study of the Cherenkov imager of the AMS experiment

International Nuclear Information System (INIS)

Aguayo, P.; Aguilar-Benitez, M.; Arruda, L.; Barao, F.; Barreira, G.; Barrau, A.; Baret, B.; Belmont, E.; Berdugo, J.; Boudoul, G.; Borges, J.; Buenerd, M.; Casadei, D.; Casaus, J.; Delgado, C.; Diaz, C.; Derome, L.; Eraud, L.; Gallin-Martel, L.; Giovacchini, F.; Goncalves, P.; Lanciotti, E.; Laurenti, G.; Malinine, A.; Mana, C.; Marin, J.; Martinez, G.; Menchaca-Rocha, A.; Palomares, C.; Pereira, R.; Pimenta, M.; Protasov, K.; Sanchez, E.; Seo, E.-S.; Sevilla, I.; Torrento, A.; Vargas-Trevino, M.; Veziant, O.

2006-01-01

The AMS experiment includes a Cherenkov imager for mass and charge identification of charged cosmic rays. A second generation prototype has been constructed and its performances evaluated both with cosmic ray particles and with beam ions. In-beam tests have been performed using secondary nuclei from the fragmentation of 20GeV/c per nucleon Pb ions and 158GeV/c per nucleon In from the CERN SPS in 2002 and 2003. Partial results are reported. The performances of the prototype for the velocity and the charge measurements have been studied over the range of ion charge Z-bar 30. A sample of candidate silica aerogel radiators for the flight model of the detector has been tested. The measured velocity resolution of the detector was found to scale with Z -1 as expected, with a value σ(β)/β∼0.7-110 -3 for singly charged particles and an asymptotic limit in Z of 0.4-0.6x10 -4 . The measured charge resolution obtained for the n=1.05 aerogel radiator material selected for the flight model of the detector is σ(Z)=0.18 (statistical) -bar 0.015 (systematic), ensuring a good charge separation up to the iron element, for the prototype in the reported experimental conditions

Integral test for Np237 and Am241 cross sections in JENDL, ENDF and JEF libraries

International Nuclear Information System (INIS)

Iwasaki, Tomohiko; Unesaki, Hironobu; Kitada, Takanori

2002-01-01

Experiments using Kyoto University critical assembly (KUCA) were performed for measuring the capture and fission reaction rates of 237 Np and 241 Am. A back-to-back fission chamber was employed for the measurement of the fission rate of 237 Np and 241 Am relative to 235 U. The capture rate of 237 Np relative to 197 Au was measured by using activation method. Eleven cores, of which the spectra were changed systematically, were mocked up for the present measurements. Five cores among the eleven were utilized for the fission reaction rate measurement. The experiment was analyzed using the Monte Carlo code MVP, the transport code TWOTRAN and the diffusion code CITATION using the libraries based on JENDL3.2, ENDF/B-VI and JEF2.2. As the results, for 237 Np, JENDL3.2 showed good agreement for both capture and fission. However, for the fission rate of 241 Am, JENDL3.2 underestimates 15-20%. On the other hand, ENDF/B-VI and JEF2.2 show different C/Es for 237 Np and 241 Am. (author)

25 November 2008 - State Councilor in charge of Science, Technology and Education Y. Liu, People's Repblic of China, visiting AMS experiment with CERN Director-General R. Aymar and AMS Collaborator Y. Yang.

CERN Multimedia

Maximilien Brice

2008-01-01

25 November 2008 - State Councilor in charge of Science, Technology and Education Y. Liu, People's Repblic of China, visiting AMS experiment with CERN Director-General R. Aymar and AMS Collaborator Y. Yang.

Tritium AMS for biomedical applications

International Nuclear Information System (INIS)

Roberts, M.L.; Velsko, C.; Turteltaub, K.W.

1993-08-01

We are developing 3 H-AMS to measure 3 H activity of mg-sized biological samples. LLNL has already successfully applied 14 C AMS to a variety of problems in the area of biomedical research. Development of 3 H AMS would greatly complement these studies. The ability to perform 3 H AMS measurements at sensitivities equivalent to those obtained for 14 C will allow us to perform experiments using compounds that are not readily available in 14 C-tagged form. A 3 H capability would also allow us to perform unique double-labeling experiments in which we learn the fate, distribution, and metabolism of separate fractions of biological compounds

The field migration tests of 237Np, 238Pu, 241Am and 90Sr in aerated loess, aquifer and engineering barrier materials

International Nuclear Information System (INIS)

Li Shushen; Wang Zhiming; Zhao Yingjie; Fan Zhiwen; Liu Chunli; An Yongfeng; Yang Yue'e; Wu Qinghua

2003-01-01

This paper introduces the field migration tests of 237 Np, 238 Pu, 241 Am and 90 Sr in aerated loess, aquifer and engineering barrier materials. The tests in the aerated loess and engineering barrier materials were carried out under both natural and artificial sprinkling (15 mm/d) conditions. The tests in aquifer were carried out in both assemblies packed with undisturbed aquifer media and a definite undisturbed area. The results indicate that after 3 years tests no significant migrations were seen for all nuclides in engineering barrier materials under two kinds of conditions and in aerated loess under natural conditions. For the aerated loess under artificial sprinkling conditions, 2.7 cm (center of mass) migration in the area directly below the sand tracer layer (named as area 1) and 13 cm (peak) migration in the area outside the area 1 for 90 Sr were observed; There was no migration for 237 Np, 238 Pu and 241 Am. It was discovered that the sand layer used as carrier of nuclide tracer has barrier effect on unsaturated water and an influence on nuclide migration. This has been demonstrated by the inter comparison experiment with both sand and loess as tracer carrier. In the tracer tests of undisturbed aquifer area there was no significant migration of 237 Np, 238 Pu, 241 Am and 90 Sr after 1023 days. In the assembly 8 there was no significant migration for 238 Pu and 241 Am and a small backward migration 0.95 cm for 237 Np and 4.7 cm migration (center of mass) for 90 Sr were observed. The tests also indicate that there is no significant difference of nuclide migration in ordinary and degraded cement

Design, Characterization and Test of the Associative Memory Chip AM06 for the Fast TracKer System

CERN Document Server

Liberali, Valentino; The ATLAS collaboration

2016-01-01

We present the performance of the new Associative Memory (AM) chip, designed and manufactured in 65 nm CMOS technology. The AM06 is the 6th version of a highly parallel ASIC processor for pattern recognition in high energy physics experiments. The AM06 is based on the XORAM cell architecture, which has been specifically designed to reduce power consumption and control complexity. The AM06 is a large chip, which contains memory banks that store all data of interest. The basic unit is a word of 18 bit. A group of 8 words (each of them related to a detector layer) is called a “pattern”. Each AM06 chip stores 2^17 patterns. The AM06 integrates serializer and deserializer IP blocks (working up to 2.4 GHz), to avoid routing congestion at the board level. AM06 is a complex VLSI chip, designed combining full-custom memory arrays, standard logic cells and IP blocks. It occupies a silicon area of 168 mm^2 and it contains about 421 millions transistors. The AM06 chip is able to perform a synchronous bitwise comparis...

Beam polarimetry in the CBELSA/TAPS experiment; Strahlpolarimetrie am CBELSA/TAPS Experiment

Energy Technology Data Exchange (ETDEWEB)

Kammer, Susanne

2010-02-19

In the identification of nucleon resonances polarization observables play an important role. For the photoproduction experiments of the CBELAS/TAPS assembly at the accelerator facility ELSA in the framework of this thesis linearly and circularly polarized were realized and prepared. Linearly polarized photons were produced on a diamond crystal under usage of the coherent bremsstrahlung. By alignment of the crystal in the bremsstrahlung coherent intensity increasements in form of pronounced edges could be generated. The number of the polarized photons lying in the increasement determines in comparison to the incoherently produced background the degree of polarization. The position of the coherent edge could be tuned by means of control distributions to an arbitrary position in the measured energy spectrum as well as the degree of polarization of the photons optimized. For the production of circularly polarized photons longitudinally polarized electrons on the bremsstrahlung target are required. The polarization transfer of the bremsstrahlung process is uniquely given by the QED, so that the degree of polarization of the photons can be determined via a measurement of the electron-beam polarization. With this goal a for the first time in the CBELSA/TAPS applied momentum-selecting Moeller polarimeter was developed and integrated in the photon-tagging facility. Via a change of the beam helicity the counting-rate asymmetry for parallely and antiparallely beam and target electrons was measured and the degree of polarization of the electrons at beam energies of 2350 MeV determined to typically above 60%. By means of dedicated test measurements and simulations the functionality of the Moeller polarimeter was checked and the relative systematic uncertainty determined to 1%. Since 2007 the Moeller polarimeter essential for the double-polarization experiments is in current operation. Finally a method was sketched, in which via the known cross-section asymmetry of the

Conception and fabrication of innovative Am-Based targets: the ca mix/Cochix experiment

International Nuclear Information System (INIS)

Schmidt, N.; Croixmarie, Y.; Abonneau, E.; Ottaviani, J.P.; Donnet, L.; Desmouliere, F.; Konings, R.J.M.; Fernandez, A.

2003-01-01

A large experimental programme has been planned to be carried out in the French PHENIX reactor. The purpose is to evaluate the technical feasibility of minor actinide transmutation in fast reactors. Two major series of experiments have been designed for the heterogeneous transmutation mode. The first one, the MATINA (Matrices for Incineration of Actinides) series, aims at testing both different inert matrices in a fast flux and different concepts. The study is generic and focuses on the material behaviour under representative irradiation conditions. Targets are free of minor actinides to make the fabrication and design steps easier and faster. The second one, ECRIX, CAMIX (Compounds of Americium in PHENIX) and COCHIX (Concept Optimized microstructure in PHENIX), is a further step in the demonstration phase of the ''once-through'' transmutation and deals with Am-bearing targets irradiated in a fast neutron spectrum ''locally'' moderated. The moderator materials tested will be calcium hydride CaH 2-x (cases of ECRIX-H, CAMIX and COCHIX) and boron carbide 11 B 4 C (case of ECRIX-B) in order to accelerate the process of transmutation significantly. (author)

AMS of {sup 14}C at low energies

Energy Technology Data Exchange (ETDEWEB)

Suter, M.; Huber, R.; Jacob, S. [ETHZ, Zurich (Switzerland); Synal, H.A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1997-09-01

At the ETH/PSI AMS facility {sup 14}C test measurements have been performed at low terminal voltages of 0.5 and 1 MV in order to study the feasibility of AMS with very small accelerators. These experiments have demonstrated that interfering molecules ({sup 13}CH and {sup 12}CH{sub 2}) in charge states 1{sup +} and 2{sup +} can be destroyed in an adequate Ar gas stripper. These new results imply the feasibility of a new generation of very small accelerator systems for {sup 14}C. (author) 1 fig., 3 refs.

Progress on multi-nuclide AMS of JAEA-AMS-TONO

Science.gov (United States)

Saito-Kokubu, Yoko; Matsubara, Akihiro; Miyake, Masayasu; Nishizawa, Akimitsu; Ohwaki, Yoshio; Nishio, Tomohiro; Sanada, Katsuki; Hanaki, Tatsumi

2015-10-01

The JAEA-AMS-TONO (Japan Atomic Energy Agency's Accelerator Mass Spectrometer established at the Tono Geoscience Center) facility has been used for the dating of geological samples. The AMS system is versatile, based on a 5 MV tandem Pelletron-type accelerator. Since its establishment in 1997, the AMS system has been used for measurement of carbon-14 (14C) mainly for 14C dating studies in neotectonics and hydrogeology, in support of JAEA's research on geosphere stability applicable to the long-term isolation of high-level radioactive waste. Results of the measurement of 14C in soils and plants has been applied to the dating of fault activity and volcanism. Development of beryllium-10 (10Be) and aluminum-26 (26Al) AMS systems are now underway to enhance the capability of the multi-nuclide AMS in studies of dating by cosmogenic nuclides. The 10Be-AMS system has already been used for routine measurements in applied studies and improvements of the measurement technique have been made. Now we plan to fine tune the system and perform test measurements to develop the 26Al-AMS system.

Progress on multi-nuclide AMS of JAEA-AMS-TONO

Energy Technology Data Exchange (ETDEWEB)

Saito-Kokubu, Yoko, E-mail: kokubu.yoko@jaea.go.jp [Japan Atomic Energy Agency, Toki, Gifu 509-5102 (Japan); Matsubara, Akihiro [Japan Atomic Energy Agency, Toki, Gifu 509-5102 (Japan); Miyake, Masayasu; Nishizawa, Akimitsu; Ohwaki, Yoshio; Nishio, Tomohiro; Sanada, Katsuki [Pesco Corp., Ltd., Toki, Gifu 509-5123 (Japan); Hanaki, Tatsumi [Japan Atomic Energy Agency, Toki, Gifu 509-5102 (Japan)

2015-10-15

The JAEA-AMS-TONO (Japan Atomic Energy Agency’s Accelerator Mass Spectrometer established at the Tono Geoscience Center) facility has been used for the dating of geological samples. The AMS system is versatile, based on a 5 MV tandem Pelletron-type accelerator. Since its establishment in 1997, the AMS system has been used for measurement of carbon-14 ({sup 14}C) mainly for {sup 14}C dating studies in neotectonics and hydrogeology, in support of JAEA’s research on geosphere stability applicable to the long-term isolation of high-level radioactive waste. Results of the measurement of {sup 14}C in soils and plants has been applied to the dating of fault activity and volcanism. Development of beryllium-10 ({sup 10}Be) and aluminum-26 ({sup 26}Al) AMS systems are now underway to enhance the capability of the multi-nuclide AMS in studies of dating by cosmogenic nuclides. The {sup 10}Be-AMS system has already been used for routine measurements in applied studies and improvements of the measurement technique have been made. Now we plan to fine tune the system and perform test measurements to develop the {sup 26}Al-AMS system.

Track calorimeter (TCAL) of alpha magnetic spectrometer (AMS) (a particle physics experiment on the international space station alpha)

International Nuclear Information System (INIS)

Anosov, V.; Baranov, S.; Bednyakov, V.

1999-01-01

Based on the simulation and R and D results the JINR project - to supplement AMS with a finely granulated scintillator calorimeter (TCAL) - is discussed. The project cost is about 1 million USD. TCAL would essentially increase the AMS potential in the studies of antimatter, matter and missing matter in the experiments in outer space

Operation of the Electronics for the AMS-02RICH Detector Prototype

Energy Technology Data Exchange (ETDEWEB)

Aguayo, P.; Aguilar, M.; Berdugo, J.; Casaus, J.; Delgado, C.; Diaz, C.; Fernandez, C.; Garcia-Tabares, L.; Lanciotti, E.; Mana, C.; Marin, J.; Martinez, G.; Palomares, C.; Sanchez, E.; Sevilla, I.; Torrento, A.; Wilmott, C.; Yanez, J.

2002-07-01

The operation and behaviour of the RICH prototype electronics developed for the AMS-02 experiment is presented. It includes results and conclusions obtained from experimental tests data with cosmic rays. (Author)

Progress in AMS measurements at the LLNL spectrometer

International Nuclear Information System (INIS)

Southon, J.R.; Vogel, J.S.; Trumbore, S.E.; Davis, J.C.; Roberts, M.L.; Caffee, M.; Finkel, R.; Proctor, I.D.; Heikkinen, D.W.; Berno, A.J.; Hornady, R.S.

1991-06-01

The AMS measurement program at LLNL began in earnest in late 1989, and has initially concentrated on 14 C measurements for biomedical and geoscience applications. We have now begun measurements on 10 Be and 36 Cl, are presently testing the spectrometer performance for 26 Al and 3 H, and will begin tests on 7 Be, 41 Ca and 129 I within the next few months. Our laboratory has a strong biomedical AMS program of 14 C tracer measurements involving large numbers of samples (sometimes hundreds in a single experiment) at 14 C concentrations which are typically .5--5 times Modern, but are occasionally highly enriched. The sample preparation techniques required for high throughput and low cross-contamination for this work are discussed elsewhere. Similar demands are placed on the AMS measurement system, and in particular on the ion source. Modifications to our GIC 846 ion source, described below, allow us to run biomedical and geoscience or archaeological samples in the same source wheel with no adverse effects. The source has a capacity for 60 samples (about 45 unknown) in a single wheel and provides currents of 30--60μA of C - from hydrogen-reduced graphite. These currents and sample capacity provide high throughput for both biomedical and other measurements: the AMS system can be started up, tuned, and a wheel of carbon samples measured to 1--1.5% in under a day; and 2 biomedical wheels can be measured per day without difficulty. We report on the present status of the Lawrence Livermore AMS spectrometer, including sample throughput and progress towards routine 1% measurement capability for 14 C, first results on other isotopes, and experience with a multi-sample high intensity ion source. 5 refs

AMS ready for launch

CERN Multimedia

Katarina Anthony

2011-01-01

On 29 April, the Alpha Magnetic Spectrometer (AMS) will complete its long expedition to the International Space Station on board the space shuttle Endeavour. The Endeavour is set to lift off from NASA’s Kennedy Space Station at 15:47 EST (21:47 CET).   Samuel Ting, principal investigator for the AMS project, and Rolf Heuer, CERN Director-General, visit the Kennedy Space Centre before the AMS launch.  Courtesy of NASA and Kennedy Space Center. AMS is a CERN recognised experiment, created by an internal collaboration of 56 institutes. It will be the first large magnetic spectrometer to be used in space, and has been designed to function as an external module on the ISS. AMS will measure cosmic rays without atmospheric interference, allowing researchers on the ground to continue their search for dark matter and antimatter in the Universe. Data collected by AMS will be analysed in CERN’s new AMS Control Centre in Building 946 (due for completion in June 2011). The End...

An Additive Manufacturing Test Artifact

Science.gov (United States)

Moylan, Shawn; Slotwinski, John; Cooke, April; Jurrens, Kevin; Donmez, M Alkan

2014-01-01

A test artifact, intended for standardization, is proposed for the purpose of evaluating the performance of additive manufacturing (AM) systems. A thorough analysis of previously proposed AM test artifacts as well as experience with machining test artifacts have inspired the design of the proposed test artifact. This new artifact is designed to provide a characterization of the capabilities and limitations of an AM system, as well as to allow system improvement by linking specific errors measured in the test artifact to specific sources in the AM system. The proposed test artifact has been built in multiple materials using multiple AM technologies. The results of several of the builds are discussed, demonstrating how the measurement results can be used to characterize and improve a specific AM system. PMID:26601039

A high resolution, low power time-of-flight system for the space experiment AMS

International Nuclear Information System (INIS)

Alvisi, D.; Anselmo, F.; Baldini, L.; Bari, G.; Basile, M.; Bellagamba, L.; Bruni, A.; Bruni, G.; Boscherini, D.; Casadei, D.; Cara Romeo, G.; Castellini, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; De Pasquale, S.; Giusti, P.; Iacobucci, G.; Laurenti, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Palmonari, F.; Polini, A.; Recupero, S.; Sartorelli, G.; Williams, C.; Zichichi, A.

1999-01-01

The system of plastic scintillator counters for the AMS experiment is described. The main characteristics of the detector are: (a) large sensitive area (four 1.6 m 2 planes) with small dead space; (b) low-power consumption (150 W for the power and the read-out electronics of 336 PMs); (c) 120 ps time resolution

AM06: the Associative Memory chip for the Fast TracKer in the upgraded ATLAS detector

CERN Document Server

Annovi, Alberto; The ATLAS collaboration; Calderini, Giovanni; Crescioli, Francesco

2016-01-01

\\abstract{This paper describes the AM06 chip, which is a highly parallel processor for pattern recognition in high energy physics experiments. It contains memory banks that store data organized in 18 bit words; a group of 8 words is called ``pattern''. Each AM06 chip can store up to 2$^{17}$ patterns. The AM06 integrates serializer/deserializer IP blocks at 2 Gbit/s for input/output communication, to avoid routing congestion at the board level. The AM06 is a complex chip. It has been designed in 65 nm CMOS, combining full-custom memory arrays, standard logic cells and IP blocks. It occupies a silicon area of 168 mm$^2$ and contains 421 millions transistors. The AM06 can perform bitwise comparison at a rate of 100 kHz. Thanks to the XORAM cell and to the design optimization, the AM06 consumes about 1 fJ/bit per comparison. The AM06 has been fabricated and successfully tested with a dedicated test system.

AmO₂ Analysis for Analytical Method Testing and Assessment: Analysis Support for AmO₂ Production

Energy Technology Data Exchange (ETDEWEB)

Kuhn, Kevin John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bland, Galey Jean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fulwyler, James Brent [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Garduno, Katherine [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Keller, Russell C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Klundt, Dylan James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lujan, Elmer J. W [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mark, Zoe Francoise Elise [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mathew, Kattathu Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ortega, Laura Claire [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ottenfeld, Chelsea Faith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Porterfield, Donivan R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rearick, Michael Sean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rim, Jung Ho [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Schake, Ann Rene [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Schappert, Michael Francis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Stanley, Floyd E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Thomas, Mariam R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wylie, Ernest Miller II [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Xu, Ning [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tandon, Lav [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-09-08

Americium oxide samples will be measured for various analytes to support AmO₂ production. The key analytes that are currently requested by the Am production customer at LANL include total Am content, Am isotopics, Pu assay, Pu isotopics, and trace element content including ²³⁷Np content. Multiple analytical methods will be utilized depending on the sensitivity, accuracy and precision needs of the Am matrix. Traceability to the National Institute of Standards and Technology (NIST) will be achieved, where applicable, by running NIST traceable quality control materials. This given that there are no suitable AmO₂ reference materials currently available for requested analytes. The primary objective is to demonstrate the suitability of actinide analytical chemistry methods to support AmO₂ production operations.

The use of AMS to the biomedical sciences

International Nuclear Information System (INIS)

Vogel, J.S.

1991-04-01

The Center for Accelerator Mass Spectroscopy (AMS) began making AMS measurements in 1989. Biomedical experiments were originally limited by sample preparation techniques, but we expect the number of biomedical samples to increase five-fold. While many of the detailed techniques for making biomedical measurements resemble those used in other fields, biological tracer experiments differ substantially from the observational approaches of earth science investigators. The role of xenobiotius in initiating mutations in cells is of particular interest. One measure of the damage caused to the genetic material is obtained by counting the number of adducts formed by a chemical agent at a given dose. AMS allows direct measurement of the number of adducts through stoichiometric quantification of the 14 C label attached to the DNA after exposure to a labelled carcinogen. Other isotopes of interest include tritium, 36 Cl, 79 SE, 41 Ca, 26 Al and 129 I. Our experiments with low dose environmental carcinogens reflect the protocols which will become a common part of biomedical AMS. In biomedical experiments, the researcher defines the carbon to be analyzed through dissection and/or chemical purification; thus the sample is ''merely'' combusted and graphitized at the AMS facility. However, since biomedical samples can have a 14 C range of five orders of magnitude, preparation of graphite required construction of a special manifold to prevent cross-contamination. Additionally, a strain of 14 C-depleted C57BL/6 mice is being developed to further reduce background in biomedical experiments. AMS has a bright and diverse future in radioisotope tracing. Such work requires a dedicated amalgamation of AMS scientists and biomedical researchers who will redesign experimental protocols to maximize the AMS technique and minimize the danger of catastrophic contamination. 18 refs., 4 figs., 1 tab

Cosmic ray and gamma astrophysics with the AMS-02 experiment

International Nuclear Information System (INIS)

Natale, Sonia

2006-01-01

The Alpha Magnetic Spectrometer (AMS) is a particle physics detector designed to operate on the International Space Station (ISS) for a minimum period of three years. The aim of AMS is the direct detection of charged particles in the rigidity range from 0.5 GV to few TV to perform high statistics studies of cosmic rays in space and a search for antimatter and dark matter. AMS will provide precise gamma measurements in the GeV range. In addition, the good angular resolution and identification capabilities of the detector will allow clean studies of galactic and extra-galactic sources, the diffuse gamma background and gamma ray bursts

An Oracle(c) database for the AMS experiment

International Nuclear Information System (INIS)

Boschini, M.; Gervasi, M.; Grandi, D.; Rancoita, P.G.; Trombetta, L.; Usoskin, I.G.

1999-01-01

We present hardware and software technologies implemented for the AMS Milano Data Center. Goal of the AMS Milano Data Center is to provide data collected during the STS-91 Space Shuttle flight to users and to provide a User Interface as well to manage the data properly. Data are stored in a database that provides high level query and retrieval features, the support being a magneto-optical juke-box. We describe the use of proprietary software (Oracle(c)) as well as custom-written software to enhance access performances. In particular we underscore the use of the Oracle Call Interfaces as a powerful tool to interface the database and the operating system in a natural way

AMS gets lift on space shuttle Discovery

CERN Multimedia

2009-01-01

AMS-02, the CERN-recognized experiment that will seek dark matter, missing matter and antimatter in Space aboard the International Space Station (ISS), has recently got the green light to be part of the STS-134 NASA mission in 2010. Installation of AMS detectors in the Prévessin experiment hall.In a recent press release, NASA announced that the last or last-but-one mission of the Space Shuttle programme would be the one that will deliver AMS, the Alpha Magnetic Spectrometer, to the International Space Station. The Space Shuttle Discovery is due to lift off in July 2010 from Kennedy Space Center and its mission will include the installation of AMS to the exterior of the space station, using both the shuttle and station arms. "It wasn’t easy to get a lift on the Space Shuttle from the Bush administration," says professor Samuel Ting, spokesperson of the experiment, "since during his administration all the funds for space research w...

The new AMS control centre

CERN Multimedia

Anaïs Schaeffer

2011-01-01

Construction work for the future AMS control room began in November 2010 and should be finished this June. The new building, which will have been completed in record time thanks to the professionalism of the project team, will soon be ready to receive the initial data from the AMS experiment.     Luigi Scibile and Michael Poehler, from the GS department, at the AMS control centre construction site.   The Alpha Magnetic Spectrometer (AMS) is due to wing its way towards the International Space Station (ISS) on board the shuttle Discovery in April. Mainly intended for research on antimatter and dark matter, the data collected by AMS will be sent to Houston in the United States and then directly to CERN’s new Building 946. Construction work for the AMS control centre building on the Route Gentner at CERN’s Prévessin site started in November 2010 and must be completed in time to receive the first data from the spectrometer in June. “It normall...

Esperimento AMS: problemi teorici e sperimentali nella ricerca di antimateria in raggi cosmici

OpenAIRE

Casadei, D

1998-01-01

In this thesis are reported the design and the tests that have been done on the prototype counters of the Time of Flight (TOF) system of the AMS (Alpha Magnetic Spectrometer) experiment. The behaviour of the Hamamatsu R5900 under vacuum test is also shown. (text is in italian)

Esperimento AMS problemi teorici e sperimentali nella ricerca di antimateria in raggi cosmici

CERN Document Server

Casadei, D

1998-01-01

In this thesis are reported the design and the tests that have been done on the prototype counters of the Time of Flight (TOF) system of the AMS (Alpha Magnetic Spectrometer) experiment. The behaviour of the Hamamatsu R5900 under vacuum test is also shown. (text is in italian)

The LLNL AMS facility

International Nuclear Information System (INIS)

Roberts, M.L.; Bench, G.S.; Brown, T.A.

1996-05-01

The AMS facility at Lawrence Livermore National Laboratory (LLNL) routinely measures the isotopes 3 H, 7 Be, 10 Be, 14 C, 26 Al, 36 Cl, 41 Ca, 59,63 Ni, and 129 I. During the past two years, over 30,000 research samples have been measured. Of these samples, approximately 30% were for 14 C bioscience tracer studies, 45% were 14 C samples for archaeology and the geosciences, and the other isotopes constitute the remaining 25%. During the past two years at LLNL, a significant amount of work has gone into the development of the Projectile X-ray AMS (PXAMS) technique. PXAMS uses induced characteristic x-rays to discriminate against competing atomic isobars. PXAMS has been most fully developed for 63 Ni but shows promise for the measurement of several other long lived isotopes. During the past year LLNL has also conducted an 129 I interlaboratory comparison exercise. Recent hardware changes at the LLNL AMS facility include the installation and testing of a new thermal emission ion source, a new multianode gas ionization detector for general AMS use, re-alignment of the vacuum tank of the first of the two magnets that make up the high energy spectrometer, and a new cryo-vacuum system for the AMS ion source. In addition, they have begun design studies and carried out tests for a new high-resolution injector and a new beamline for heavy element AMS

FoAM Kernow Activity Report 2016

OpenAIRE

Griffiths, Amber; Griffiths, David

2016-01-01

This review shows selected projects from the FoAM Kernow studio in 2016. FoAM is a network of transdisciplinary labs at the intersection of art, science, nature and everyday life. FoAM’s members are generalists - people who work across disparate fields in an entangled, speculative culture. Research and creative projects at FoAM combine elements of futurecrafting, citizen science, prototyping, experience design and process facilitation to re-imagine possible futures, and artistic experime...

FoAM Kernow Activity Report 2017

OpenAIRE

Griffiths, Amber; Weatherill, Aidan; Griffiths, David

2017-01-01

This review shows selected projects from the FoAM Kernow studio in 2017. FoAM is a network of transdisciplinary labs at the intersection of art, science, nature and everyday life. FoAM’s members are generalists - people who work across disparate fields in an entangled, speculative culture. Research and creative projects at FoAM combine elements of futurecrafting, citizen science, prototyping, experience design and process facilitation to re-imagine possible futures.

Engineering and management experience at Texas A&M Transportation Institute

Science.gov (United States)

Chowdhury, Arif Tahjibul

This manuscript presents the author's engineering and management experience during his internship in the Materials and Pavements (M&P) Division at the Texas A&M Transportation Institute (TTI), and is a record of study for the Doctor of Engineering at Texas A&M University. Through this internship, he met his established internship objectives of gaining technical knowledge as well as knowledge and skills in project management, organizational communication, and quality management of pavement condition data, and of attaining professional development. In meeting these objectives, the author describes the history, mission, and organizational structure of his workplace. He also presents his experience of developing and delivering a two-week training course on pavement design and construction in Kosovo. Participating in a number of professional development training courses and other activities prepared him for working as an engineering manager. These activities include Delta-T leadership training, an instructor development course, a time management and organizational skills course, and the M&P Division lecture series. Leadership and skills learned through the Delta-T program were beneficial for the employee as well as the employer. For the class project, the author and his teammates performed a study dealing with improving TTI's deliverables. The Delta-T team composed a report summarizing their efforts of examining the current state of TTI's project deliverables, the deliverables' shortcomings, and potential enhancements to expand the deliverables' appeal to additional types of potential users outside the traditional research community. The team also developed a prototype web-based model of deliverables and presented some implementation recommendations. Participating in the Texas Department of Transportation's (TxDOT's) pavement surface distress data collection program enabled the author to become familiar with pavement distress data quality management and thus attain the

Design of a graphite-moderated {sup 241}Am-Li neutron field to simulate reactor spectra

Energy Technology Data Exchange (ETDEWEB)

Tsujimura, N., E-mail: tsujimura.norio@jaea.go.j [Nuclear Fuel Cycle Engineering Laboratories, Japan Atomic Energy Agency, 4-33, Tokai-mura, Ibaraki-ken, 319-1194 (Japan); Yoshida, T. [Nuclear Fuel Cycle Engineering Laboratories, Japan Atomic Energy Agency, 4-33, Tokai-mura, Ibaraki-ken, 319-1194 (Japan)

2010-12-15

A neutron calibration field using {sup 241}Am-Li sources and a moderator was designed to simulate the neutron fields found outside a reactor. The moderating assembly selected for the design calculation consists of a cube of graphite blocks with dimensions of 50 cm by 50 cm by 50 cm, in which the {sup 241}Am-Li sources are placed. Monte Carlo calculations revealed the optimal depth of the source to be 15 cm. This moderated neutron source can be used to provide a test field that has a large number of intermediate energy neutrons with a small portion of MeV component.

AM06: the Associative Memory chip for the Fast TracKer in the upgraded ATLAS detector

International Nuclear Information System (INIS)

Annovi, A.; Beretta, M. M.; Calderini, G.; Crescioli, F.; Frontini, L.; Liberali, V.; Shojaii, S.R.; Stabile, A.

2017-01-01

This paper describes the AM06 chip, which is a highly parallel processor for pattern recognition in the ATLAS high energy physics experiment. The AM06 contains memory banks that store data organized in 18 bit words; a group of 8 words is called 'pattern'. Each AM06 chip can store up to 131 072 patterns. The AM06 is a large chip, designed in 65 nm CMOS, and it combines full-custom memory arrays, standard logic cells and serializer/deserializer IP blocks at 2 Gbit/s for input/output communication. The overall silicon area is 168 mm 2 and the chip contains about 421 million transistors. The AM06 receives the detector data for each event accepted by Level-1 trigger, up to 100 kHz, and it performs a track reconstruction based on hit information from channels of the ATLAS silicon detectors. Thanks to the design of a new associative memory cell and to the layout optimization, the AM06 consumption is only about 1 fJ/bit per comparison. The AM06 has been fabricated and successfully tested with a dedicated test system.

Assessment of Alphamagnetic Spectrometer (AMS) Upper Experiment Structural Configuration Shielding Effectiveness Associated with Change from Cryo-Cooled Magnet to Permanent Magnet

Science.gov (United States)

Scully, Robert

2012-01-01

In the spring of 2010, the Alpha Magnetic Spectrometer 2 (AMS-02) underwent a series of system level electromagnetic interference control measurements, followed by thermal vacuum testing. Shortly after completion of the thermal vacuum testing, the project decided to remove the cryogenically cooled superconducting magnet, and replace it with the original permanent magnet design employed in the earlier AMS- 01 assembly. Doing so necessitated several structural changes, as well as removal or modification of numerous electronic and thermal control devices and systems. At this stage, the project was rapidly approaching key milestone dates for hardware completion and delivery for launch, and had little time for additional testing or assessment of any impact to the electromagnetic signature of the AMS-02. Therefore, an analytical assessment of the radiated emissions behavioural changes associated with the system changes was requested.

General concept and present status of the AMS - project

International Nuclear Information System (INIS)

Stan-Sion, C.; Plostinaru, D.; Catana, L.; Radulescu, M.; Marinescu, L.; Dima, R.

1998-01-01

The Institute of Nuclear Physics and Engineering, IFIN-HH, Bucharest started in 1996 the Construction Project for an AMS facility in Bucharest. The Project is supported by the German-Romanian scientific cooperation project RUM-013-97. In the frame of this project, scientific research, construction activities of electronic and mechanical devices and activities for calibration and optimization were performed. The activities in this year are concentrated on experimental tests and optimization of the AMS analysis procedure and on improving the tandem acceleration and transmission capability. These are as follows: - construction and tests of a high current sputter source, with spherical ionizer and automatic many-sample changer. Experimental tests and measurements of emittance and beam profile; - construction of the Injector Platform; - construction and tests of a Bragg - charged particle detector; - calibration and optimization experiments of the AMS ensemble. The AMS facility is based on the 8 MV - FN tandem accelerator and has the following main components: the AMS ion injector, a Wien - velocity filter, a 60 angle bending magnet and the particle detection system. For heavy particle detection we constructed a Bragg ionization chamber. This should be used for standard AMS measurements. A specific part of the AMS facility represents the AMS injector deck. The main components are: the high current sputter source, the analyzing double focusing magnet, two optical systems, a four-slit beam defining system in front of the analyzing magnet and a four-slit aperture with remote controlled Faraday cup (for beam current integration of stable isotopes) after the magnet. Finally, the pre-acceleration tube (40 kV) connects the ensemble to the ground potential of the accelerator beam line. For AMS measurements, the sputter ion source is able to provide both high beam current and small beam emittance. These characteristics are necessary in order to achieve high analyzing

Critical Evaluation of an Intercalibration Project Focused on the Definition of New Multi-Element Soil Reference Materials (AMS-MO1 and AMS-ML1

Directory of Open Access Journals (Sweden)

Livia Vittori Antisari

2014-12-01

Full Text Available Soils are complex matrices and their geochemical investigation necessarily needs reliable Certified Reference Materials (CRMs, i.e. standards, to support analytical precision and accuracy. In particular, the definition of soil multi-element CRMs is particularly complex and involves an inter-laboratory program that employs numerous analytical techniques. In this study, we present the results of the inter-calibration experiment focused on the certification of two new soil standards named AMS-ML1 and AMS-MO1. The two soils developed on sandstone and serpentinite parent materials, respectively. The experiment involved numerous laboratories and focused on the evaluation of soil physicochemical parameters and geochemical analyses of major and trace elements by X-ray fluorescence (XRF and Inductive Coupled Plasma techniques (ICP-OES and ICP-MS. The data was statistically elaborated. Three levels of repeatability and accuracy in function of the different analytical methods and instrumentation equipment was observed. The statistical evaluation of the results obtained by ICP-OES on Aqua Regia extracts (i.e., Lilliefors test for normally, Grubbs test for outliers, Cochran test for outliers in variances and ANOVA allowed to computed some certified values for the two proposed soil standards. This preliminary study will represent the first step of a more thorough intercalibration ring-test involving a higher number of laboratories, in order to propose the investigated matrices as CRMs.

AMS Weather Studies and AMS Ocean Studies: Dynamic, College-Level Geoscience Courses Emphasizing Current Earth System Data

Science.gov (United States)

Brey, J. A.; Geer, I. W.; Moran, J. M.; Weinbeck, R. S.; Mills, E. W.; Blair, B. A.; Hopkins, E. J.; Kiley, T. P.; Ruwe, E. E.

2008-12-01

AMS Weather Studies and AMS Ocean Studies are introductory college-level courses developed by the American Meteorological Society, with NSF and NOAA support, for local offering at undergraduate institutions nationwide. The courses place students in a dynamic and highly motivational educational environment where they investigate the atmosphere and world ocean using real-world and real-time environmental data. Over 360 colleges throughout the United States have offered these courses in course environments ranging from traditional lecture/laboratory to completely online. AMS Diversity Projects aim to increase undergraduate student access to the geosciences through implementation of the courses at minority-serving institutions and training programs for MSI faculty. The AMS Weather Studies and AMS Ocean Studies course packages consist of a hard-cover, 15-chapter textbook, Investigations Manual with 30 lab-style activities, and course website containing weekly current weather and ocean investigations. Course instructors receive access to a faculty website and CD containing answer keys and course management system-compatible files, which allow full integration to a college's e-learning environment. The unique aspect of the courses is the focus on current Earth system data through weekly Current Weather Studies and Current Ocean Studies investigations written in real time and posted to the course website, as well as weekly news files and a daily weather summary for AMS Weather Studies. Students therefore study meteorology or oceanography as it happens, which creates a dynamic learning environment where student relate their experiences and observations to the course, and actively discuss the science with their instructor and classmates. With NSF support, AMS has held expenses-paid course implementation workshops for minority-serving institution faculty planning to offer AMS Weather Studies or AMS Ocean Studies. From May 2002-2007, AMS conducted week-long weather workshops

Critical mass calculations for 241Am, 242mAm and 243Am

International Nuclear Information System (INIS)

Dias, Hemanth; Tancock, Nigel; Clayton, Angela

2003-01-01

Criticality mass calculations are reported for 241 Am, 242m Am and 243 Am using the MONK and MCNP computer codes with the UKNDL, JEF-2.2, ENDF/B-VI and JENDL-3.2 nuclear data libraries. Results are reported for spheres of americium metal and dioxide in bare, water reflected and steel reflected systems. Comparison of results led to the identification of a serious inconsistency in the 241 Am ENDF/B-VI DICE library used by MONK - this demonstrates the importance of using different codes to verify critical mass calculations. The 241 Am critical mass estimates obtained using UKNDL and ENDF/B-VI show good agreement with experimentally inferred data, whilst both JEF-2.2 and JENDL-3.2 produce higher estimates of critical mass. The computed critical mass estimates for 242m Am obtained using ENDF/B-VI are lower than the results produced using the other nuclear data libraries - the ENDF/B-VI fission cross-section for 242m Am is significantly higher than the other evaluations in the fast region and is not supported by recent experimental data. There is wide variation in the computed 243 Am critical mass estimates suggesting that there is still considerable uncertainty in the 243 Am nuclear data. (author)

[Experimental investigations of 211Am accumulation by macrophytes of the Yenisei River].

Science.gov (United States)

Bolsunovskiĭ, A Ia; Zotina, T A

2002-01-01

Experiments were carried out in which 241Am was added to water samples containing macrophytes of the Yenisei River, and the radionuclide absorption rates and concentration factors were determined for the plants. It has been shown that the water moss (Fontinalis antipyretica) has a higher capacity to accumulate 241Am than the Canadian pondweed (Elodea canadensis) does. The laboratory experiments revealed that the capacity of dead biomass of the Canadian pondweed to accumulate 241Am is twice higher than that of living biomass. In contrast, no significant increase in 241Am accumulation by dead biomass of the water moss has been recorded. The transuranic element 241Am was firmly fixed by the plant biomass and was not released into water in the course of long-duration experiments.

Recent results from the AMS-02 experiment

Directory of Open Access Journals (Sweden)

Vecchi Manuela

2015-01-01

Full Text Available The AMS-02 detector is a large acceptance magnetic spectrometer operating onboard the International Space Station since May 2011. The main goals of the detector are the search for antimatter and dark matter in space, as well as the measurement of cosmic ray composition and flux. Precise measurements of cosmic ray positrons and electrons are presented in this document, based on 41×109 events collected during the first 30 months of operations.

Cosmic rays measurements between 1 GeV and 1 PeV by AMS and CREAM experiments; Mesures des rayons cosmiques entre le GeV et le PeV par les experiences AMS et CREAM

Energy Technology Data Exchange (ETDEWEB)

Mangin-Brinet, M

2007-11-15

The AMS (Alpha Magnetic Spectrometer) and CREAM (Cosmic Ray Energetics and Mass) experiments that are devoted to the detection of cosmic radiations have a similar architecture and both use a Cherenkov detector whose scintillating material is a silicon aerogel. The performance of the Cherenkov detector rests on an accurate knowledge of the refractive index of the aerogel plane. This report deals with an adequate methodology of measuring the refractive index. The first chapter reviews the contributions of AMS and CREAM experiments to the physics of cosmic radiations. The second chapter presents different methods used for mapping the refractive index of the aerogel plane. The prism method is based on the measurement of the deflection of a laser beam through the sides of an aerogel tile. The most satisfying method to measure the changes in the refractive index is to use an electron beam, in this case any change infers a change in the emission angle of the Cherenkov photons that can be detected and the value of the refractive index is deduced. A new method based on the deflection of a laser beam on the 2 parallel sides of an aerogel tile has been developed. The characterization of the 2 Cherenkov detectors are given in the second and the third chapter. The last chapter presents some aspects of the simulation works and of the data processing. (A.C.)

AMS02 Ecal γ trigger performance measured at the October 2004 CERN test beam

International Nuclear Information System (INIS)

Brun, Pierre; Rosier-Lees, Sylvie

2006-01-01

Test beam data collected in October 2004 at CERN PS to validate the AMS 02 Ecal Inter- mediate Board (EIB) are analyzed. After describing the experimental setup and the event samples, results concerning noise measurement, trigger efficiency and threshold accuracy are presented. They demonstrate that the EIB fulfills the physics requirements. Therefore the analog part of the trigger is validated, and hardware choices are also made towards the final device. (authors)

Actinide AMS at DREAMS

Energy Technology Data Exchange (ETDEWEB)

Khojasteh, Nasrin B.; Merchel, Silke; Rugel, Georg; Scharf, Andreas; Ziegenruecker, Rene [HZDR, Dresden (Germany); Pavetich, Stefan [HZDR, Dresden (Germany); ANU, Canberra (Australia)

2016-07-01

Radionuclides such as {sup 236}U and {sup 239}Pu were introduced into the environment by atmospheric nuclear weapon tests, reactor accidents (Chernobyl, Fukushima), releases from nuclear reprocessing facilities (Sellafield, La Hague), radioactive waste disposal, and accidents with nuclear devices (Palomares, Thule) [1]. Accelerator Mass Spectrometry (AMS) is the most sensitive method to measure these actinides. The DREsden AMS (DREAMS) facility is located at a 6 MV accelerator, which is shared with ion beam analytics and implantation users, preventing major modifications of the accelerator and magnetic analyzers. DREAMS was originally designed for {sup 10}Be, {sup 26}Al, {sup 36}Cl, {sup 41}Ca, and {sup 129}I. To modify the system for actinide AMS, a Time-of-Flight (TOF) beamline at the high-energy side has been installed and performance tests are on-going. Ion beam and detector simulations are carried out to design a moveable ionization chamber. Especially, the detector window and anode dimensions have to be optimized. This ionization chamber will act as an energy detector of the system and its installation is planned as closely as possible to the stop detector of the TOF beamline for highest detection efficiency.

Plant uptake and transport of 241Am

International Nuclear Information System (INIS)

Wallace, A.; Romney, E.M.; Mueller, R.T. Sr.; soufi, S.M.

1981-01-01

We conducted several experiments with 241 Am to obtain a more complete understanding of how this transuranium element is absorbed and transported in plants. In a plant species (Tamarix pentandra Pall.) that has salt glands in the leaves excreting NaCl and other ions, 241 Am was not pumped through these glands. Cyanide, which forms complexes with any metals, when applied to a calcareous soil, greatly increased the transport of 241 Am into stems and leaves of bush bean plants. Radioactive cyanide ( 14 C) was also transported to leaves and stems. When radish was grown in both calcareous and noncalcareous soils, 241 Am appeared to be fixed on the peel so firmly that it was resistant to removal by HNO 3 washing. The chelating agent DTPA induced increased transport of 241 Am to leaves and into the fleshy roots of the radish. Data for Golden Cross hybrid corn grown in solution culture showed at least seven times as much 241 Am transport to the xylem exudatields are corrected by recovery of added tracers

Present status of the JAEA-AMS-TONO. 2012

International Nuclear Information System (INIS)

Saito-Kokubu, Yoko; Matsubara, Akihiro; Ishimaru, Tsuneari; Hanaki, Tatsumi; Nishizawa, A.; Miyake, M.; Ohwaki, Y.; Nishio, T.; Tanaka, Takayuki

2013-01-01

The Tono Geoscience Center (TGC) of JAEA has been conducting research into deep underground environments for R and D program related to the geological disposal of High-Level Radioactive Waste. The AMS system of the TGC has routinely been used for 14 C-AMS since it started to be operated in 1998. In recent years, we have promoted the development of system technology for routine 10 Be-AMS. An inter-laboratory comparison of the 14 C-AMS was performed with the JAEA-AMS-MUTSU. The data of isotope ratios obtained with both AMS systems showed that there is no significant difference between them. In the development for the 10 Be-AMS, several test measurements have been performed by using standard samples. The results indicated fairly robust stability of data quality, which contributed to complete the development for routine 10 Be measurement. We are now in the stage of the development for routine 26 Al-AMS. (author)

Cosmic rays measurements between 1 GeV and 1 PeV by AMS and CREAM experiments

International Nuclear Information System (INIS)

Mangin-Brinet, M.

2007-11-01

The AMS (Alpha Magnetic Spectrometer) and CREAM (Cosmic Ray Energetics and Mass) experiments that are devoted to the detection of cosmic radiations have a similar architecture and both use a Cherenkov detector whose scintillating material is a silicon aerogel. The performance of the Cherenkov detector rests on an accurate knowledge of the refractive index of the aerogel plane. This report deals with an adequate methodology of measuring the refractive index. The first chapter reviews the contributions of AMS and CREAM experiments to the physics of cosmic radiations. The second chapter presents different methods used for mapping the refractive index of the aerogel plane. The prism method is based on the measurement of the deflection of a laser beam through the sides of an aerogel tile. The most satisfying method to measure the changes in the refractive index is to use an electron beam, in this case any change infers a change in the emission angle of the Cherenkov photons that can be detected and the value of the refractive index is deduced. A new method based on the deflection of a laser beam on the 2 parallel sides of an aerogel tile has been developed. The characterization of the 2 Cherenkov detectors are given in the second and the third chapter. The last chapter presents some aspects of the simulation works and of the data processing. (A.C.)

Accumulation and release of 241Am by a macrophyte of the Yenisei River (Elodea canadensis)

International Nuclear Information System (INIS)

Bolsunovsky, A.; Zotina, T.; Bondareva, L.

2005-01-01

The source of radioactive contamination of the Yenisei River floodplain, including contamination with transuranic elements, is the Mining-and-Chemical Combine of the Russian Ministry of Atomic Energy, which has for many years been producing weapons-grade plutonium. Transuranic elements have been detected not only in the soil and sediment of the river but also in the biomass of aquatic plants. This work is an investigation of accumulation and release of 241 Am by a submerged macrophyte of the Yenisei River (Elodea canadensis) in laboratory experiments. In 2000-2003, laboratory experiments were carried out with biomass of E. canadensis Mich. and filtered river water. The samples were collected from the Yenisei River upstream of the discharge of the Combine's radioactive effluent. The experiments showed that 241 Am is accumulated by Elodea biomass: the activity concentration of 241 Am can reach 3280 ± 240 Bq/g, with the concentration factor for 241 Am 16 600 ± 2200 l/kg. Results of chemical fractionation have proved that in the course of 241 Am accumulation by Elodea biomass, 241 Am tightly bound to biomass increases from 11% to 27% of the total 241 Am in the biomass. Release of 241 Am from the decaying Elodea biomass has been evaluated experimentally. By the end of the experiment (lasting up to 127 days), the Elodea plants had lost up to 65% of their initial 241 Am activity and the rate of 241 Am release into the water environment reached 23 Bq/day

Accumulation and release of 241Am by a macrophyte of the Yenisei River (Elodea canadensis).

Science.gov (United States)

Bolsunovsky, A; Zotina, T; Bondareva, L

2005-01-01

The source of radioactive contamination of the Yenisei River floodplain, including contamination with transuranic elements, is the Mining-and-Chemical Combine of the Russian Ministry of Atomic Energy, which has for many years been producing weapons-grade plutonium. Transuranic elements have been detected not only in the soil and sediment of the river but also in the biomass of aquatic plants. This work is an investigation of accumulation and release of 241Am by a submerged macrophyte of the Yenisei River (Elodea canadensis) in laboratory experiments. In 2000-2003, laboratory experiments were carried out with biomass of E. canadensis Mich. and filtered river water. The samples were collected from the Yenisei River upstream of the discharge of the Combine's radioactive effluent. The experiments showed that 241Am is accumulated by Elodea biomass: the activity concentration of 241Am can reach 3280+/-240 Bq/g, with the concentration factor for 241Am 16 600+/-2200l/kg. Results of chemical fractionation have proved that in the course of 241Am accumulation by Elodea biomass, 241Am tightly bound to biomass increases from 11% to 27% of the total 241Am in the biomass. Release of 241Am from the decaying Elodea biomass has been evaluated experimentally. By the end of the experiment (lasting up to 127 days), the Elodea plants had lost up to 65% of their initial 241Am activity and the rate of 241Am release into the water environment reached 23 Bq/day.

AMS of actinides in ground- and seawater: a new procedure for simultaneous analysis of U, Np, Pu, Am and Cm isotopes below ppq levels

Energy Technology Data Exchange (ETDEWEB)

Quinto, Francesca; Lagos, Markus; Plaschke, Markus; Schaefer, Thorsten; Geckeis, Horst [Institut fuer Nukleare Entsorgung, KIT, Eggenstein-Leopoldshafen (Germany); Steier, Peter [VERA Laboratory, University of Vienna, Vienna (Austria)

2015-07-01

U-236, Np-237, Pu isotopes and Am-243 were determined in ground- and seawater samples at levels below ppq with a maximum sample size of 0.250 l. Such high sensitivity measurement was possible by using accelerator mass spectrometry (AMS) with an improved gas stripping and an additional high resolving magnet. The use of non-isotopic tracers was investigated in order to allow the determination of those nuclides, namely Np-237 and Am-243, for which isotopic tracers for mass spectrometry are rarely available. The actinides were concentrated from the sample matrix via iron hydroxide co-precipitation and measured sequentially without previous chemical separation from each other. The analytical method was validated with the analysis of IAEA 443 seawater Reference Material and applied to background samples from the Colloid Formation and Migration project at the Grimsel Test Site and to sea- and freshwater samples affected solely by global fallout. The sensitivity of the presented analytical method provides the capability to study the long-term release of actinide tracers in field experiments as well as the transport of actinides in a variety of environmental systems.

Am/Cm TTR testing - 3/8-inch glass beads evaluation in CIM5

International Nuclear Information System (INIS)

Witt, D. C.

2000-01-01

To facilitate the procurement and handling of the glass former for Am/Cm vitrification in the F-Canyon MPPF, 1/4 inch and 3/8 inch diameter glass beads were purchased from Corning for evaluation in the 5 inch Cylindrical Induction Melter (CIM5). Prior to evaluating the beads in the CIM5, tests were conducted in the Drain Tube Test Stand (DTTS) with 1/4 inch beads, 3/8 inch beads, and a 50/50 mixture to identify any process concerns. Results of the DTTS tests are summarized in Attachment 1. A somewhat larger volume expansion was experienced in all three DTTS runs as compared to a standard run using cullet. Further testing of the use of glass beads in the CIM5 was requested by the Design Authority as Task 1.02 of Technical Task Request 99-MNSS/SE-006. Since the Technical Task Plan was not yet approved, the completion of this task was conducted under an authorization request approved by the SRTC Laboratory Director, S. Wood. This request is included as Attachment 2

The Alpha Magnetic Spectrometer (AMS)

International Nuclear Information System (INIS)

Alcaraz, J.; Alpat, B.; Ambrosi, G.; Anderhub, H.; Ao, L.; Arefiev, A.; Azzarello, P.; Babucci, E.; Baldini, L.; Basile, M.; Barancourt, D.; Barao, F.; Barbier, G.; Barreira, G.; Battiston, R.; Becker, R.; Becker, U.; Bellagamba, L.; Bene, P.; Berdugo, J.; Berges, P.; Bertucci, B.; Biland, A.; Bizzaglia, S.; Blasko, S.; Boella, G.; Boschini, M.; Bourquin, M.; Brocco, L.; Bruni, G.; Buenerd, M.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Camps, C.; Cannarsa, P.; Capell, M.; Casadei, D.; Casaus, J.; Castellini, G.; Cecchi, C.; Chang, Y.H.; Chen, H.F.; Chen, H.S.; Chen, Z.G.; Chernoplekov, N.A.; Chiueh, T.H.; Chuang, Y.L.; Cindolo, F.; Commichau, V.; Contin, A.; Crespo, P.; Cristinziani, M.; Cunha, J.P. da; Dai, T.S.; Deus, J.D.; Dinu, N.; Djambazov, L.; DAntone, I.; Dong, Z.R.; Emonet, P.; Engelberg, J.; Eppling, F.J.; Eronen, T.; Esposito, G.; Extermann, P.; Favier, J.; Fiandrini, E.; Fisher, P.H.; Fluegge, G.; Fouque, N.; Galaktionov, Yu.; Gervasi, M.; Giusti, P.; Grandi, D.; Grimm, O.; Gu, W.Q.; Hangarter, K.; Hasan, A.; Hermel, V.; Hofer, H.; Huang, M.A.; Hungerford, W.; Ionica, M.; Ionica, R.; Jongmanns, M.; Karlamaa, K.; Karpinski, W.; Kenney, G.; Kenny, J.; Kim, W.; Klimentov, A.; Kossakowski, R.; Koutsenko, V.; Kraeber, M.; Laborie, G.; Laitinen, T.; Lamanna, G.; Laurenti, G.; Lebedev, A.; Lee, S.C.; Levi, G.; Levtchenko, P.; Liu, C.L.; Liu, H.T.; Lopes, I.; Lu, G.; Lu, Y.S.; Luebelsmeyer, K.; Luckey, D.; Lustermann, W.; Mana, C.; Margotti, A.; Mayet, F.; McNeil, R.R.; Meillon, B.; Menichelli, M.; Mihul, A.; Mourao, A.; Mujunen, A.; Palmonari, F.; Papi, A.; Park, I.H.; Pauluzzi, M.; Pauss, F.; Perrin, E.; Pesci, A.; Pevsner, A.; Pimenta, M.; Plyaskin, V.; Pojidaev, V.; Postolache, V.; Produit, N.; Rancoita, P.G.; Rapin, D.; Raupach, F.; Ren, D.; Ren, Z.; Ribordy, M.; Richeux, J.P.; Riihonen, E.; Ritakari, J.; Roeser, U.; Roissin, C.; Sagdeev, R.; Sartorelli, G.; Schultz von Dratzig, A.; Schwering, G.; Scolieri, G.; Seo, E.S.; Shoutko, V.; Shoumilov, E.; Siedling, R.; Son, D.; Song, T.; Steuer, M.; Sun, G.S.; Suter, H.; Tang, X.W.; Ting, S.C.C.Samuel C.C.; Ting, S.M.; Tornikoski, M.; Torsti, J.; Tr umper, J.; Ulbricht, J.; Urpo, S.; Usoskin, I.; Valtonen, E.; Vandenhirtz, J.; Velcea, F.; Velikhov, E.; Verlaat, B.; Vetlitsky, I.; Vezzu, F.; Vialle, J.P.; Viertel, G.; Vite, D.; Gunten, H. Von; Wicki, S.W.S. Waldmeier; Wallraff, W.; Wang, B.C.; Wang, J.Z.; Wang, Y.H.; Wiik, K.; Williams, C.; Wu, S.X.; Xia, P.C.; Yan, J.L.; Yan, L.G.; Yang, C.G.; Yang, M.; Ye, S.W.; Yeh, P.; Xu, Z.Z.; Zhang, H.Y.; Zhang, Z.P.; Zhao, D.X.; Zhu, G.Y.; Zhu, W.Z.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.

2002-01-01

The Alpha Magnetic Spectrometer (AMS) is a large acceptance (0.65 sr m 2 ) detector designed to operate in the International Space Station (ISS) for three years. The purposes of the experiment are to search for cosmic antimatter and dark matter and to study the composition and energy spectrum of the primary cosmic rays. A 'scaled-down' version has been flown on the Space Shuttle Discovery for 10 days in June 1998. The complete AMS is programmed for installation on the ISS in October 2003 for an operational period of 3 yr. This contribution reports on the experimental configuration that will be installed on the ISS

The Texas A&M Radioisotope Production and Radiochemistry Program

International Nuclear Information System (INIS)

Akabani, Gamal

2016-01-01

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

The Texas A&M Radioisotope Production and Radiochemistry Program

Energy Technology Data Exchange (ETDEWEB)

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

2016-08-31

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

The Texas A&M Radioisotope Production and Radiochemistry Program

International Nuclear Information System (INIS)

Akabani, Gamal

2016-01-01

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

The Texas A&M Radioisotope Production and Radiochemistry Program

Energy Technology Data Exchange (ETDEWEB)

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

2016-10-28

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

Determining the Cause for Low Flowrates during Am/Cm Simulant Testing in F-Area

International Nuclear Information System (INIS)

Lambert, D.P.

2003-01-01

30,000 gallons of Americium/Curium (Am/Cm) slurry was transferred from F-Canyon to Tank 51H over an 18 hour period. This was the first continuous transfer of waste from F-Canyon to a waste tank. Prior to the successful Am/Cm transfer, the facility had experienced difficulties in transferring simulated solutions. A team of personnel from several divisions worked in well-coordinated fashion to determine a cost effective means to identify and mitigate the obstacles to the transfer. The team successfully diagnosed the causes of the problem, replicated the observed behavior in laboratory tests and computer modeling, and recommended controls and changes to facility operations. A successful simulant transfer demonstrated readiness for the Am/Cm transfer. This report summarizes the results of the investigation to determine the cause for the poor flow rate experienced during simulant testing in F-Area. Flow rates as low as 3 gallons per minute (gpm) occurred at the end of the transfer. This report includes an explanation for the low flow rate and recommends controls to prevent the reoccurrence. We recommend the following controls to prevent the reoccurrence of slow flows. 1. Control the temperature of the contents of the simulant and real waste storage tanks near ambient during preparation and storage. Temperature control will minimize the inadvertent evaporation of the slurry and minimize any negative impacts of a high temperature during precipitation and storage of the slurry. 2. Avoid any evolution that can inadvertently concentrate the solutions. Well mixed storage tanks and the proper jet or pump operation are necessary to ensure a uniform slurry transfer and avoid concentrating a heel in Tank 13.3. 3. Minimize the air purge rate in the storage tanks after preparation of the simulant and actual waste. The purge leads to slow evaporation of the slurry as well as addition of carbonates, from carbon dioxide sorption. 4. Replace evaporative losses by adding inhibited water

Nuclear Safeguards and Non-Proliferation Education at Texas A&M University

International Nuclear Information System (INIS)

Gariazzo, C.; Charlton, W.

2015-01-01

The MS degree in Nuclear Engineering - Non-proliferation at Texas A&M University is administered by the Nuclear Security Science and Policy Institute (NSSPI). The oldest and largest of its kind in the US, 45 M.S. and 15 Ph.D. students conducted technical research in relevant areas: safeguards, nuclear security, non-proliferation, and arms control. In addition to focusing on graduate education with a wide combination of internationally-recognized talent, NSSPI faculty lead research and service activities in safeguarding of nuclear materials and reducing nuclear threats. Texas A&M Nuclear Engineering students take relevant nonproliferation and safeguards courses (within the College of Engineering and the Texas A&M Bush School of Government) as well as conduct their research under competent experts. The complete educational experience here is unique because of the strong research and educational support NSSPI provides. This paper will detail these endeavors and convey contributions from NSSPI for developing next-generation safeguards experts via practical experiences and strong affiliations with real-world practitioners. The safeguards and non-proliferation education programme blends historical, legal, technical and policy aspects that is unique for a technical university such as Texas A&M. Beyond classroom lectures, NSSPI provides opportunities for students ranging from asynchronous learning modules to practical experiences. Publicly-available self-paced, online course modules in basic and advanced safeguards education have been developed by NSSPI as supplemental nuclear education for students and professionals. By leveraging NSSPI's contacts, students participate in exchange programmes with international institutions as well as partake in experiences like engaging safeguards practitioners at nuclear fuel cycle facilities around the world, conducting experiments at internationally-renowned laboratories, and representing their communities at workshops worldwide

Accumulation and release of {sup 241}Am by a macrophyte of the Yenisei River (Elodea canadensis)

Energy Technology Data Exchange (ETDEWEB)

Bolsunovsky, A. [Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk 660036 (Russian Federation)]. E-mail: radecol@ibp.ru; Zotina, T. [Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk 660036 (Russian Federation); Bondareva, L. [Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences, Krasnoyarsk 660036 (Russian Federation)

2005-07-01

The source of radioactive contamination of the Yenisei River floodplain, including contamination with transuranic elements, is the Mining-and-Chemical Combine of the Russian Ministry of Atomic Energy, which has for many years been producing weapons-grade plutonium. Transuranic elements have been detected not only in the soil and sediment of the river but also in the biomass of aquatic plants. This work is an investigation of accumulation and release of {sup 241}Am by a submerged macrophyte of the Yenisei River (Elodea canadensis) in laboratory experiments. In 2000-2003, laboratory experiments were carried out with biomass of E. canadensis Mich. and filtered river water. The samples were collected from the Yenisei River upstream of the discharge of the Combine's radioactive effluent. The experiments showed that {sup 241}Am is accumulated by Elodea biomass: the activity concentration of {sup 241}Am can reach 3280 {+-} 240 Bq/g, with the concentration factor for {sup 241}Am 16 600 {+-} 2200 l/kg. Results of chemical fractionation have proved that in the course of {sup 241}Am accumulation by Elodea biomass, {sup 241}Am tightly bound to biomass increases from 11% to 27% of the total {sup 241}Am in the biomass. Release of {sup 241}Am from the decaying Elodea biomass has been evaluated experimentally. By the end of the experiment (lasting up to 127 days), the Elodea plants had lost up to 65% of their initial {sup 241}Am activity and the rate of {sup 241}Am release into the water environment reached 23 Bq/day.

NIKHEF: AmPS of electron beam

International Nuclear Information System (INIS)

Anon.

1992-01-01

Now operational at the Dutch National Institute for Nuclear Physics and High Energy Physics (NIKHEF), Amsterdam, is a new tool for studying the electromagnetic properties of nuclei. Called AmPS - Amsterdam pulse stretcher - this ring provides experiments with a smoother, almost continuous supply of electrons

AMS_02 Particle Physics Detector Technologies Orbiting the Earth (2/2)

CERN Multimedia

CERN. Geneva

2012-01-01

AMS-02 has taken the high performance technologies used in particle physics and implemented them for use in low Earth orbit. Safety aspects for the Space Shuttle flight, that carried AMS_02 to the International Space Station, Space environment and inaccessibility during the life of AMS_02 are some of the aspects which have driven the design of the experiment. The technical challenges to build such a detector have been surmounted through the close collaboration amongst the AMS scientists and industries around the world. Their efforts have resulted in the development of new technologies and higher standards of precision.

AMS_02 Particle Physics Detector Technologies Orbiting the Earth (1/2)

CERN Multimedia

CERN. Geneva

2012-01-01

AMS-02 has taken the high performance technologies used in particle physics and implemented them for use in low Earth orbit. Safety aspects for the Space Shuttle flight, that carried AMS_02 to the International Space Station, Space environment and inaccessibility during the life of AMS_02 are some of the aspects which have driven the design of the experiment. The technical challenges to build such a detector have been surmounted through the close collaboration amongst the AMS scientists and industries around the world. Their efforts have resulted in the development of new technologies and higher standards of precision.

Distribution and Excretion of Am-241 in Rats

International Nuclear Information System (INIS)

Alatas, Z; Nurhayati, S; Rahardjo, T

1996-01-01

Determination of the activity content of Am-241 administered oral y in several organs and tissues of white rats including the excretion had been carried out. The observation of Am-241 activity was carried out through surgery and for the excretion of the radionuclide by collecting urine and faces. The surgeries were conducted on the 0 (6 hours), 1, 2, 3, 4, 5, 15 and 30th day post administration of 2.965 kBq Am-241, whereas the urine and faces collections were done every other day for 30 days using metabolism cage. The result indicated that the distribution of Am-241 which found in all tested organs/tissues with various fraction is considered as the initial distribution of Am-241 in rats. The content of americium in gastrointestinal tract and lung is relatively high within the first week post contamination. And, americium activities in other organs/tissues are various with time. The excretion of Am-241 is higher via feces than that of urin, i.e up to 20% in 30 days

The read-out electronics of the AMS prototype RICH detector

International Nuclear Information System (INIS)

Gallin-Martel, L.; Eraud, L.; Pouxe, J.; Aguayo de Hoyos, P.; Marin Munoz, J.; Martinez Botella, G.

2003-01-01

A Ring Imaging Cherenkov (RICH) counter dedicated to the AMS experiment is under development. An integrated circuit has been designed with the Austriamicrosystems 0.6 πm CMOS technology to process the signals of the 16 anode PMTs used in the photon detection. To improve the detector compactness, the read out electronics is placed very close to the PMTs. This lead to the design of a detection cell that comprises: a light guide, a PMT, a high voltage divider, an analog front end chip and an analog to digital converter. The analog front-end chips were extensively and successfully tested in a laboratory environment, 96 of them are now mounted on the RICH prototype. Tests with cosmic rays have started. Ion beam tests are planed in a near future. (authors)

The AMS-02 RICH Imager Prototype - In-Beam Tests with 20 GeV/c per Nucleon Ions -

CERN Document Server

Buenerd, M.; Aguilar Benitez, M.; Arruda, L.; Barao, F.; Barrau, A.; Baret, B.; Belmont, E.; Berdugo, J.; Boudoul, G.; Borges, J.; Casadei, D.; Casaus, J.; Delgado, C.; Diaz, C.; Derome, L.; Eraud, L.; Gallin-Martel, L.; Giovacchini, F.; Goncalves, P.; Lanciotti, E.; Laurenti, G.; Malinine, A.; Mana, C.; Marin, J.; Martinez, G.; Menchaca-Rocha, A.; Palomares, C.; Pimenta, M.; Protasov, K.; Sanchez, E.; Seo, E-S.; Sevilla, I.; Torrento, A.; Vargas-Trevino, M.

2003-01-01

A prototype of the AMS Cherenkov imager (RICH) has been tested at CERN by means of a low intensity 20 GeV/c per nucleon ion beam obtained by fragmentation of a primary beam of Pb ions. Data have been collected with a single beam setting, over the range of nuclear charges 2

Advanced test reactor testing experience-past, present and future

International Nuclear Information System (INIS)

Marshall, Frances M.

2006-01-01

The Advanced Test Reactor (ATR), at the Idaho National Laboratory (INL), is one of the world's premier test reactors for providing the capability for studying the effects of intense neutron and gamma radiation on reactor materials and fuels. The physical configuration of the ATR, a 4-leaf clover shape, allows the reactor to be operated at different power levels in the corner 'lobes' to allow for different testing conditions for multiple simultaneous experiments. The combination of high flux (maximum thermal neutron fluxes of 1E15 neutrons per square centimeter per second and maximum fast [E>1.0 MeV] neutron fluxes of 5E14 neutrons per square centimeter per second) and large test volumes (up to 122 cm long and 12.7 cm diameter) provide unique testing opportunities. The current experiments in the ATR are for a variety of test sponsors - US government, foreign governments, private researchers, and commercial companies needing neutron irradiation services. There are three basic types of test configurations in the ATR. The simplest configuration is the sealed static capsule, which places the capsule in direct contact with the primary coolant. The next level of experiment complexity is an instrumented lead experiment, which allows for active control of experiment conditions during the irradiation. The most complex experiment is the pressurized water loop, in which the test sample can be subjected to the exact environment of a pressurized water reactor. For future research, some ATR modifications and enhancements are currently planned. This paper provides more details on some of the ATR capabilities, key design features, experiments, and future plans

New results from the
 AMS experiment on the International Space Station

CERN Multimedia

CERN. Geneva

2016-01-01

The Alpha Magnetic Spectrometer, AMS, is a general purpose high energy particle phys- ics detector. It was installed on the International Space Station, ISS, on 19 May 2011 to conduct a unique long duration mission of fundamental physics research in space. Knowledge of the precise rigidity dependence of the proton and helium flux is important in understanding the origin, acceleration, and propagation of cosmic rays. Pre- cise measurements of the proton and of the helium flux in primary cosmic rays with rigidities (momentum/charge) up to the TV scale are presented and the detailed varia- tion with rigidity of the flux spectral indices will be discussed. A precision measurement by AMS of the antiproton flux and antiproton-to-proton ratio in primary cosmic rays in the rigidity range from 1 to 450 GV is presented. This measurement increases the precision of the previous observations and significantly extends their rigidity range. It shows that the antiproton-to-proton ratio remains constant above ∼60 GV. In a...

Comparison Of ²⁵²Cf Time Correlated Induced Fisssion With AmLi Induced Fission On Fresh MTR Research Reactor Fuel

Energy Technology Data Exchange (ETDEWEB)

Joshi, Jay Prakash [Los Alamos National Laboratory

2017-03-30

The effective application of international safeguards to research reactors requires verification of spent fuel as well as fresh fuel. To accomplish this goal various nondestructive and destructive assay techniques have been developed in the US and around the world. The Advanced Experimental Fuel Counter (AEFC) is a nondestructive assay (NDA) system developed at Los Alamos National Laboratory (LANL) combining both neutron and gamma measurement capabilities. Since spent fuel assemblies are stored in water, the system was designed to be watertight to facilitate underwater measurements by inspectors. The AEFC is comprised of six ³He detectors as well as a shielded and collimated ion chamber. The ³He detectors are used for active and passive neutron coincidence counting while the ion chamber is used for gross gamma counting. Active coincidence measurement data is used to measure residual fissile mass, whereas the passive coincidence measurement data along with passive gamma measurement can provide information about burnup, cooling time, and initial enrichment. In the past, most of the active interrogation systems along with the AEFC used an AmLi neutron interrogation source. Owing to the difficulty in obtaining an AmLi source, a ²⁵²Cf spontaneous fission (SF) source was used during a 2014 field trail in Uzbekistan as an alternative. In this study, experiments were performed to calibrate the AEFC instrument and compare use of the ²⁵²Cf spontaneous fission source and the AmLi (α,n) neutron emission source. The ²⁵²Cf source spontaneously emits bursts of time-correlated prompt fission neutrons that thermalize in the water and induce fission in the fuel assembly. The induced fission (IF) neutrons are also time correlated resulting in more correlated neutron detections inside the ³He detector, which helps reduce the statistical errors in doubles when using the ²⁵²Cf interrogation source instead of

The influence of impurities for cross section measurement of {sup 241,243}Am(n,f) reactions

Energy Technology Data Exchange (ETDEWEB)

Kai, Tetsuya; Kobayashi, Katsuhei; Yamamoto, Shuji; Fujita, Yoshiaki; Kimura, Itsuro; Miyoshi, Mitsuharu; Yamamoto, Hideki [Kyoto Univ. (Japan); Shinohara, Nobuo

1997-03-01

The influence of the impurities on the fission cross section measurements for {sup 241}Am and {sup 243}Am has been investigated with the practical results. Following cases have been considered as the influence of impurities; (a) experiments with the {sup 241}Am sample that contains impurities originally, and (b) experiments with the {sup 243}Am sample that contains impurities produced by {alpha}, {beta} decays after the chemical purification. The present study has demonstrated the usefulness of pure samples by the comparison of the experiments using the sample on the market with those using the pure sample processed by the authors. Particularly on the case (b), the correction of the impurity through the periodical measurements was experimentally performed (about 18% around 0.3 eV in 4 weeks after the chemical purification). (author)

Bioremoval of Am-241 and Cs-137 from liquid radioactive wasters by bacterial consortiums; Biorremocao de Am-241 e Cs-137 de rejeitos radioativos liquidos por consorcios bacterianos

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Rafael Vicente de Padua; Lima, Josenilson B. de; Gomes, Mirella C.; Borba, Tania R.; Bellini, Maria Helena; Marumo, Julio Takehiro; Sakata, Solange Kazumi, E-mail: rpadua@ipen.b, E-mail: sksakata@ipen.b, E-mail: jblima@ipen.b, E-mail: mbmarumo@ipen.b, E-mail: jtmarumo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-10-26

This paper evaluates the capacity of two bacterial consortiums of impacted areas in removing the Am-241 and Cs-137 from liquid radioactive wastes.The experiments indicated that the two study consortiums were able to remove 100% of the Cs-137 and Am-241 presents in the waste from 4 days of contact. These results suggest that the bio removal with the selected consortiums, can be a viable technique for the treatment of radioactive wastes containing Am-241 and Cs-137

Experimental verification for standard analysis procedure of 241Am in food

International Nuclear Information System (INIS)

Liu Qingfen; Zhu Hongda; Liu Shutian; Pan Jingshun; Yang Dating

2005-01-01

Objective: The briefly experimental verification for 'determination of 241 Am in food' has been described. Methods: The overall recovery, the MDL of method and decontamination experiment has been done by standard analysis procedure. Results: The overall recovery is 76.26 ± 4.1%. The MDL is 3.4 x 10 -5 Bq/g ash, decontamination factor is higher than 10 3 for Po, 10 2 for U, Th, Pu and 60 for 237 Np. Conclusion: The results showed that the overall recovery is quite high and reliable, the MDL of method is able to meet examining 241 Am limited values in foods. the obtained decontamination factors of recommended procedure can meet analysis of 241 Am in food examination. Venifying results of the procedure are satisfied by using 243 Am spike and 241 Am standard reference material. (authors)

New applications of 14C measurements at the Lund AMS Facility

International Nuclear Information System (INIS)

Stenstroem, K.

1995-11-01

Some new applications of accelerator mass spectroscopy (AMS) with 14 C are presented. In the first part the sample preparation used for production of elemental carbon at the Lund AMS facility is described. The second part concerns the release of 14 C from nuclear power plants. In a one-year study, the total airborne discharge of 14 C from two Swedish reactors was measured. In another study, the fraction of 14 CO 2 of the total airborne 14 C release was determined. The third part of the thesis involves the use of 14 C in nuclear medicine. The long-term retention of 14 C-labelled triolein after a fat-malabsorption test has been investigated by means of AMS by analysis of expired CO 2 . The possibilities of using ultra-low amounts of activity for fat-malabsorption tests, employing AMS technique, is demonstrated. In the last part AMS and 14 C-labelled tracers are used in food chemistry studies of interactions between foods and packaging materials. 22 refs, 8 figs, 2 tabs

Uptake and intracellular activity of AM-1155 in phagocytic cells.

Science.gov (United States)

Yamamoto, T; Kusajima, H; Hosaka, M; Fukuda, H; Oomori, Y; Shinoda, H

1996-01-01

The uptake and intracellular activity of AM-1155 in murine J774.1 macrophages and human polymorphonuclear leukocytes were investigated. AM-1155 penetrated phagocytic cells rapidly and reversibly, although the penetration process was not affected by metabolic inhibitors such as sodium fluoride, cyanide m-chlorophenylhydrazone, or ouabain or by nucleoside transport system inhibitors such as adenosine. The intracellular concentration-to-extracellular concentration ratio of AM-1155 in both cell types of phagocytes ranged from 5 to 7. These ratios were almost equal to those for sparfloxacin. The intracellular activity of AM-1155 in J774.1 macrophages, examined with Staphylococcus aureus 209P as a test bacterium, was dependent on the extracellular concentration. AM-1155 at a concentration of 1 microgram/ml reduced the number of viable cells of S. aureus ingested by more than 90%. The intracellular activity of AM-1155 was more potent than those of sparfloxacin, ofloxacin, ciprofloxacin, flomoxef, and erythromycin. These results suggest that the potent intracellular activity of AM-1155 might mainly be due to the high intracellular concentration and its potent in vitro activity. PMID:9124835

{sup 137}Cs, {sup 90}Sr, {sup 241}Am and {sup 239+240}Pu radionuclides speciation in soils of the former Semipalatinsk test site

Energy Technology Data Exchange (ETDEWEB)

Kabdyrakova, A.M.; Kunduzbaeva, A.Y.; Lukashenko, S.N.; Magasheva, R.Y. [Institute of radiation safety and ecology (Kazakhstan)

2014-07-01

The paper presents results of studies into {sup 137}Cs and {sup 90}Sr, {sup 241}Am and {sup 239+240}Pu techno-genic radionuclides speciation in soils of ecosystems at different topography of the Semipalatinsk Test Site (STS), exposed to different nuclear testing. The data were obtained for radionuclides speciation in soils of the following STS ecosystems: - grassland ecosystems within near-portal areas of tunnels - horizontal adits constructed for nuclear testing, affected by radioactive-contaminated water flows from the tunnels of Degelen Site; - steppe ecosystems, exposed to ground radioactive contamination resulted from above-ground and aerial nuclear testing of different yield, as well as simulation (hydrodynamic and hydro-nuclear) experiments at 'Experimental Field' testing site. - steppe ecosystems, exposed to ground radioactive contamination caused by testing of liquid and powdery radiological warfare weapon (RWW) at Site '4 a'; - 'Northern' and 'Western' areas of STS, where concentration level of artificial radionuclides in soil is comparable with the level of global fall-outs ('background' areas). To study the radionuclides speciation, method of sequential extraction was applied, and water-soluble, exchange, organic mobile and tightly bound forms were separated. Feature of the studied grassland ecosystems is that they are developed solely along the bed of water streams flowing from tunnels and are located at small area of 1-2 m{sup 2}. Radioactive contamination of soil is caused by radioactive contaminant sorption by sediments. Despite the significant space limitation of the ecosystems content of radionuclides speciation in soil greatly varies, particularly readily-soluble and mobile forms. The variation may be explained by high humidity which makes possible both sorption and desorption processes. If basic radionuclides contributing to radioactive contamination of grassland soils at Degelen Site are {sup

"Am I carrier?" The patient's lived experience of thrombophilia genetic screening and its outcome.

Science.gov (United States)

Graffigna, Guendalina; Leone, Daniela; Vegni, Elena

2014-01-01

How do patients with thrombophilia experience a physician's request to undergo a genetic test? How do they experience the test outcome? To answer these questions, we conducted an interpretative phenomenological analysis study, based on 10 in-depth interviews with patients who underwent genetic testing for thrombophilia in Italy, half with positive and half with negative results. The experience of undergoing genetic screening for thrombophilia plays an important role in reconfiguring patients' signification of their illness experience. A positive outcome becomes a cue to reorganize in a more adaptive way the illness meaning at the cognitive and emotive levels, whereas a negative outcome appears more distressing and confusing. As a clinical implication of the study, clinicians should consider communicating carefully with the patients regardless from the positive/negative test results and they should explore the patient's specific reaction and understanding of test result.

Effects of the herbicide glyphosate on the uptake of 239Pu and 241Am to vegetation

International Nuclear Information System (INIS)

Nisbet, A.F.; Shaw, S.

1990-01-01

Glyphosate (n-phosphonomethyl glycine) is a broad spectrum herbicide widely used in lowland agriculture, forestry and improved upland pastures. Although its metal chelating properties are well established, its interaction with radionuclides remains unknown. A pot experiment was conducted to determine the effect of soil applications of glyphosate on the uptake of 239 Pu and 241 Am to peas and carrots grown in loam, peat and sand soils. Soil-to-plant transfer factors were calculated for treated and untreated soils at harvest. The most marked effect was an increase in 241 Am uptake to crops grown in loam soil. Supplementary laboratory batch experiments were conducted by shaking radiolabelled soil and its associated soil solution with glyphosate. The activity concentration of 241 Am increased ten fold in the liquid phase of loam soils treated with glyphosate. It is postulated that this 241 Am desorption could have been mediated by the formation of a stable Am-glyphosate complex which was subsequently more available for crop uptake than Am alone. (author)

Effects of silicon on mechanical properties of AM60 magnesium alloy

Directory of Open Access Journals (Sweden)

Hu Yong

2012-08-01

Full Text Available Silicon was added to improve the tensile, wear and creep behaviors of AM60 magnesium alloy in this study. The investigation has been undertaken by means of universal testing machine, HBE-3000A Brinell hardness tester, M-2000 friction-wear machine, DMA-Q800 creep machine, optical microscopy (OM and scanning electron microscopy (SEM. The results indicate that the Chinese script type Mg2Si particles are formed by adding Si into the AM60 magnesium alloy. The ultimate tensile strength and hardness of the AM60 magnesium alloy increases with the Si addition, and the ultimate tensile strength and hardness of the AM60+1.0wt.%Si alloy are increased by 12% and 19.8%, respectively in comparison with that of the AM60 magnesium alloy. The wear property and the high temperature creep property of the AM60 magnesium alloy are also improved with Si addition. The wear mechanisms of the AM60 and AM60+1.0wt.%Si alloys are adhesive wear and abrasion wear, respectively. While, the elongation of the AM60 magnesium alloy decreases with the addition of Si. The optimum Si addition content is 1.0wt.%.

Estratégia analítica para determinação de nitrito e amônia empregando spot test e análise de imagem digital

Directory of Open Access Journals (Sweden)

J. L. O. Santos

2014-11-01

Full Text Available Neste trabalho é proposta uma estratégia simples para determinação simultânea de nitrito e amônia empregando spot test e imagem digital. O método é baseado na reação do nitrito com a sulfanilamida, formando um cátion de diazônio que posteriormente é acoplado ao dicloreto de N-(1-nafitil etilenodiamina formando uma diazo composto de coloração rósea. A determinação da amônia foi realizada empregando a reação de berthelot modificada, onde o íon amônio em presença de salicilato, nitroprussiato e hipoclorito reage formando um composto de coloração verde. Os sinais analíticos foram obtidos a partir das intensidades de coloração por imagem digital no spot test do produto da reação. Após otimizações do sistema de análise e detecção, as seguintes figuras de mérito foram obtidas: concentração linear entre 0,2 a 10,0 mg L-1 para nitrito e 1,0 a 10,0 mg L-1 para a amônia. Os limites de detecção para o nitrito e amônia foram 0,05 mg L-1 e 0,27 mg L-1, respectivamente. A estratégia proposta foi aplicada com sucesso na determinação de nitrito e amônia em amostras de água subterrânea da zona urbana da cidade de Barreiras-Ba.

The AMS-02 transition radiation detector

CERN Document Server

Kirn, Th

2004-01-01

The Alpha Magnetic Spectrometer AMS02 will be equipped with a large transition radiation detector (TRD) to achieve a proton background suppression necessary for dark matter searches. The AMS02 TRD consists of 20 layers of fleece radiator each with Xe/CO//2 proportional wire straw tubes read out by a dedicated low-power data- acquisition system. A space-qualified TRD design will be presented. The performance of a 20-layer prototype was tested at CERN with electron, myon and pion beams up to l00 GeV and with protons up to 250 GeV. The beam-test results will be compared to Geant3 MC predictions. The detector is under construction at RWTH Aachen; the gas system will be built at MIT, slow-control at MIT and INFN Rome and DAQ at TH Karlsruhe. This project is funded by the German Space Agency DLR, the US Department of Energy DOE and NASA.

CologneAMS, a dedicated center for accelerator mass spectrometry in Germany

Energy Technology Data Exchange (ETDEWEB)

Dewald, A., E-mail: dewald@ikp.uni-koeln.de [CologneAMS, Institute of Nuclear Physics, University of Cologne (Germany); Heinze, S.; Jolie, J.; Zilges, A. [CologneAMS, Institute of Nuclear Physics, University of Cologne (Germany); Dunai, T.; Rethemeyer, J.; Melles, M.; Staubwasser, M. [Institute of Geology and Mineralogy, University of Cologne (Germany); Kuczewski, B. [Division of Nuclear Chemistry, University of Cologne (Germany); Richter, J. [Institute of Prehistoric Archaeology, University of Cologne (Germany); Radtke, U. [Institute of Geography, University of Cologne, Germany, Rectorate, University of Duisburg-Essen (Germany); Blanckenburg, F. von [GFZ, German Research Centre for Geosciences, Potsdam (Germany); Klein, M. [HVEE, Amersfoort (Netherlands)

2013-01-15

CologneAMS is a new centre for accelerator mass spectrometry (AMS) at University of Cologne. It has been funded by the German Research Foundation (DFG) to improve the experimental conditions especially for those German scientists that apply the AMS technique for their geologic, environmental, nuclear chemical, and nuclear astrophysical research. The new AMS-device has been built by High Voltage Engineering Europe (HVEE) and has been installed in the existing accelerator area of the Institute of Nuclear Physics. The AMS-facility is designed for the spectrometry of {sup 10}Be, {sup 14}C, {sup 26}Al, {sup 36}Cl, {sup 41}Ca, {sup 129}I in and heavy ions up to {sup 236}U and {sup 244}Pu. The central part of the AMS-facility is a 6 MV Tandetron Trade-Mark-Sign accelerator. Downstream of the high energy mass spectrometer an additional switching magnet is used as a further filter element which supplies also additional ports for future extensions of the detector systems. The current status of CologneAMS and the results of the first test measurements will be presented.

Measurement of transvers spin effects by means of two-hadron correlations in the COMPASS experiment; Messung transversaler Spineffekte mittels zwei Hadronen Korrelation am COMPASS-Experiment

Energy Technology Data Exchange (ETDEWEB)

Massmann, Frank Michael

2008-06-23

Helizitaets- Verteilungsfunktion {delta}q(x) und die transversale Quarkspin Verteilungsfunktion {delta}{sub T}q(x). Diese letztgenannte Funktion, genannt ''Transversity'' Funktion, ist chiral ungerade und kann deshalb nur in Kombination mit einer anderen chiral ungeraden Funktion gemessen werden. Eine Zugangsmoeglichkeit zur ''Transversity'' Funktion {delta}{sub T}q(x) ist die semi-inklusive zwei Hadronenproduktion in tief inelastischer Streuung an einem transversal polarisierten Target. Dabei misst man die Faltung der chiral ungeraden zwei Hadronen Interferenz Fragmentationsfunktion (IFF) H{sub 1} {sup angle} (z,M{sub h}{sup 2}) und der chiral ungeraden ''Transversity'' Funktion. Die IFF H{sub 1} {sup angle} (z,M{sub h}{sup 2}) ist der spinabhaengige Teil einer Fragmentationsfunktion, die die Fragmentation eines transversal polarisierten Quarks in zwei unpolarisierte Hadronen beschreibt. Die Produktion der zwei Hadronen erfolgt in einer Interferenz zwischen verschiedenen Wellenzustaenden der Hadronenpaare. Man misst azimuthale Asymmetrien in den erzeugten Hadronenpaaren. Die Messungen, die in dieser Arbeit beschrieben werden, wurden am COMPASS Experiment am CERN in den Jahren 2002-2004 durchgefuehrt, welches ein Feststoff Target Experiment am SPS Beschleuniger ist. Nach einer Einfuehrung werden in Kapitel 2 die zugrundeliegenden theoretischen Konzepte zur Messung der ''Transversity'' Funktion vorgestellt. In Kapitel 3 wird das COMPASS Experiment beschrieben. Schliesslich werden in Kapitel 4 die Auswertemethoden besprochen, die Ergebnisse der azimuthalen Asymmetrien gezeigt und mit theoretischen Vorhersagen verglichen. (orig.)

40 CFR 60.4212 - What test methods and other procedures must I use if I am an owner or operator of a stationary CI...

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false What test methods and other procedures... Requirements for Owners and Operators § 60.4212 What test methods and other procedures must I use if I am an... CFR 94.8, as applicable, must not exceed the NTE numerical requirements, rounded to the same number of...

The endocannabinoid transport inhibitor AM404 differentially modulates recognition memory in rats depending on environmental aversiveness

OpenAIRE

Campolongo, Patrizia; Ratano, Patrizia; Manduca, Antonia; Scattoni, Maria L.; Palmery, Maura; Trezza, Viviana; Cuomo, Vincenzo

2012-01-01

Cannabinoid compounds may influence both emotional and cognitive processes depending on the level of environmental aversiveness at the time of drug administration. However, the mechanisms responsible for these responses remain to be elucidated. The present experiments investigated the effects induced by the endocannabinoid transport inhibitor AM404 (0.5-5 mg/kg, i.p.) on bothemotional and cognitive performances of rats tested in a Spatial Open Field task and subjected to different experimenta...

Precise measurement of cosmic ray fluxes with the AMS-02 experiment

Energy Technology Data Exchange (ETDEWEB)

Vecchi, Manuela, E-mail: manuela.vecchi@ifsc.usp.br [Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970, São Carlos, SP (Brazil)

2015-12-17

The AMS-02 detector is a large acceptance magnetic spectrometer operating onboard the International Space Station since May 2011. The main goals of the detector are the search for antimatter and dark matter in space, as well as the measurement of cosmic ray composition and flux. In this document we present precise measurements of cosmic ray positrons, electrons and protons, collected during the first 30 months of operations.

Climate Controls AM Fungal Distributions from Global to Local Scales

Science.gov (United States)

Kivlin, S. N.; Hawkes, C.; Muscarella, R.; Treseder, K. K.; Kazenel, M.; Lynn, J.; Rudgers, J.

2016-12-01

Arbuscular mycorrhizal (AM) fungi have key functions in terrestrial biogeochemical processes; thus, determining the relative importance of climate, edaphic factors, and plant community composition on their geographic distributions can improve predictions of their sensitivity to global change. Local adaptation by AM fungi to plant hosts, soil nutrients, and climate suggests that all of these factors may control fungal geographic distributions, but their relative importance is unknown. We created species distribution models for 142 AM fungal taxa at the global scale with data from GenBank. We compared climate variables (BioClim and soil moisture), edaphic variables (phosphorus, carbon, pH, and clay content), and plant variables using model selection on models with (1) all variables, (2) climatic variables only (including soil moisture) and (3) resource-related variables only (all other soil parameters and NPP) using the MaxEnt algorithm evaluated with ENMEval. We also evaluated whether drivers of AM fungal distributions were phylogenetically conserved. To test whether global correlates of AM fungal distributions were reflected at local scales, we then surveyed AM fungi in nine plant hosts along three elevation gradients in the Upper Gunnison Basin, Colorado, USA. At the global scale, the distributions of 55% of AM fungal taxa were affected by both climate and soil resources, whereas 16% were only affected by climate and 29% were only affected by soil resources. Even for AM fungi that were affected by both climate and resources, the effects of climatic variables nearly always outweighed those of resources. Soil moisture and isothermality were the main climatic and NPP and soil carbon the main resource related factors influencing AM fungal distributions. Distributions of closely related AM fungal taxa were similarly affected by climate, but not by resources. Local scale surveys of AM fungi across elevations confirmed that climate was a key driver of AM fungal

Testing theory in practice: a simple experiment

NARCIS (Netherlands)

Terpstra, R.; Brezocnik, Z.; Kapus, T.; Ferreira Pires, Luis; Heerink, A.W.; Tretmans, G.J.

1996-01-01

In this paper we discuss the experiences gained in conducting a simple testing experiment. The goal of this experiment is to apply the abstract, formal testing framework [8] in a practical setting, and to indicate the critical aspects in its application to realistic testing situations. For that

Measurement of mass yields from the 241Am(2nth,f reaction at the Lohengrin Spectrometer

Directory of Open Access Journals (Sweden)

Köster U.

2013-03-01

Full Text Available The study of fission yields has a major impact on the characterization and understanding of the fission process and is mandatory for reactor applications. While the yields are known for the major actinides (235U, 239Pu in the thermal neutron-induced fission, only few measurements have been performed on 242Am. The interest of 242Am concerns the reduction of radiotoxicity of 241Am in nuclear wastes using transmutation reactions. This paper presents the measurement of the fission mass yields from the reaction 241Am(2nth,f performed at the Lohengrin mass spectrometer (ILL, France for both the light and the heavy peaks: a total of 41 mass yields have been measured. The experiment was also meant to determine whether there is a difference in mass yields between the isomeric state and the ground state as it exists in fission and capture cross sections. The method used to address this question is based on a repeated measurement of a set of fission mass yields as a function of the ratio between the 242gAm and the 242mAm fission rates. The presented experiment is also a first step towards the measurement of the isotopic fission yields of 242Am.

Bioremoval of Am-241 and Cs-137 from liquid radioactive wasters by bacterial consortiums

International Nuclear Information System (INIS)

Ferreira, Rafael Vicente de Padua; Lima, Josenilson B. de; Gomes, Mirella C.; Borba, Tania R.; Bellini, Maria Helena; Marumo, Julio Takehiro; Sakata, Solange Kazumi

2011-01-01

This paper evaluates the capacity of two bacterial consortiums of impacted areas in removing the Am-241 and Cs-137 from liquid radioactive wastes.The experiments indicated that the two study consortiums were able to remove 100% of the Cs-137 and Am-241 presents in the waste from 4 days of contact. These results suggest that the bio removal with the selected consortiums, can be a viable technique for the treatment of radioactive wastes containing Am-241 and Cs-137

Simulating Large Area, High Intensity AM0 Illumination – Test Results from Bepicolombo and Solar Orbiter Qualification

Directory of Open Access Journals (Sweden)

Oberhüttinger C.

2017-01-01

Specifically, the following topics will be treated. Different methods like electrical performance, thermo-optical and external quantum efficiency measurements have been used to characterize the behaviour of the solar cells after illumination under these conditions. A special focus has been put on the electrical performance. A comparison to other solar cell qualification tests under solely UV radiation has been undertaken. The results have also been compared to a theoretical model. However, the paper will not cover only characterization results but will also give some insight in challenges experienced during the test execution itself. Deviating from other solar cell qualification tests, a representatively equipped photovoltaic assembly on carbon fibre reinforced cyanate has also been included. On these coupon segments, solar cell assemblies connected to shunt diodes and placed next to optical surface reflectors have been exposed to AM0 illumination to qualify the solar cells including their surroundings which therefore covers also contamination effects. Last but not least, first results from the Solar Orbiter qualification are presented. This test with additional 1000 hours and increased intensity has been completed recently.

Thermal stress analysis of an Am/Cm stabilization bushing melter

International Nuclear Information System (INIS)

Gong, C.; Hardy, B.J.

1996-01-01

Decades of nuclear material production at the Savannah River Site (SRS) has resulted in the generation of large quantities of the isotopes Am 243 and Cm 244 . Currently, the Am and Cm isotopes are stored as a nitric acid solution in a tank. The Am and Cm isotopes have great commercial value but must be transferred to the Oak Ridge National Laboratory (ORNL) for processing. The nitric acid solution contains other isotopes and is intensely radioactive, which makes storage a problem and precludes shipment in the liquid form. In order to stabilize the material for onsite storage and to permit transport the material from SRS to ORNL, it has been proposed that the Am and Cm be separated from other isotopes in the solution and vitrified. The vitrification process in the Platinum-Rhodium alloy vessel generates a wide spectrum of temperature distributions. The melter is partially supported by a suspension system and confined by the flexible insulation. The combination of the fluctuation of temperature distribution and variable boundary conditions, induces stresses and strains in the melter. The thermal stress analysis is carried out with the finite element code ABAQUS. This analysis is closely associated with the design, manufacture and testing of the melter. The results were compared with the test data

Measurements of neutron cross section of the {sup 243}Am(n,{gamma}){sup 244}Am reaction

Energy Technology Data Exchange (ETDEWEB)

Hatsukawa, Yuichi; Shinohara, Nobuo; Hata, Kentaro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1998-03-01

The effective thermal neutron cross section of {sup 243}Am(n,{gamma}){sup 244}Am reaction was measured by the activation method. Highly-purified {sup 243}Am target was irradiated in an aluminum capsule by using a research reactor JRR-3M. The tentative effective thermal neutron cross sections are 3.92 b, and 84.44 b for the production of {sup 244g}Am and {sup 244m}Am, respectively. (author)

Latest Results from the AMS Experiment on the International Space Station

CERN Multimedia

CERN. Geneva

2018-01-01

In seven years on the Space Station, AMS has collected more than 115 billion charged cosmic rays with energies up to multi TeV.  The measured positron spectra agrees well with dark matter models. The energy dependence of elementary particles (electrons, positrons, protons and antiprotons)  as well as the rigidity dependence of primary cosmic rays and secondary cosmic rays are unique and distinct.  These results require a new understanding of the cosmos. 

Study of the electrochemical oxidation of Am with lacunary heteropolyanions and silver nitrate

International Nuclear Information System (INIS)

Chartier, D.

1999-01-01

Electrochemical oxidation of Am(III) with certain lacunary heteropolyanions (LHPA α 2 -P 2 W 17 O 61 10- or αSiW 11 O 39 8- ) and silver nitrate is an efficient way to prepare Am(VI). This document presents bibliographic data and an experimental study of the process. Thus, it has been established that Am(IV) is an intermediate species in the reaction and occurs in 1:1 (Amt IV LHPA) or 1:2 (Am IV (LHAP) 2 ) complexes with the relevant LHPA. These 1:1 complexes of Am(IV) have been identified and isolated in this work whereas 1:2 complexes were known from previous studies. The reactivity of these complexes in oxidation shows that 1:1 complexes of Am(IV) are oxidised much more quickly than 1:2 complexes. Apparent stability constants of Am(III) and Am(IV) complexes with the relevant LHPA have been measured for a 1 M nitric acid medium. Thermodynamic data of the reaction are then assessed: redox potentials of Am pairs are computed for a 1 M nitric acid medium containing various amount of LHPA ligands. Those results show that the role of LHPA is to stabilize the intermediate species Am(IV) by lowering the Am(IV)/Am(III) pair potential of about 1 Volt. Nevertheless, if this stabilisation is too strong (i.e. of tungsto-silicate), the oxidation of Am(IV) requires high anodic potential (more than 2 V/ENH). Then, the faradic yield of the oxidation of americium is poor because of water oxidation. This study has also shown that the main role of silver is to catalyze the electrochemical oxidation of Am IV (LHPA) X complexes. Indeed, these oxidations without silver are extremely slow. An oxygen tracer experiment has been performed during the oxidation of Am(III) in Am(VI). It has been shown that the oxygen atoms of Am(VI) (AMO 2 2+ ) come from water molecules of the solvent and not from the complexing oxygen atoms of the ligands. (author)

[Study on tests of genetics experiments in universities].

Science.gov (United States)

Jie, He; Hao, Zhang; Lili, Zhang

2015-03-01

Based on the present situation and the development of experiment tests in universities, we introduced a reform in tests of genetics experiments. According to the teaching goals and course contents of genetics experiment, the tests of genetics experiments contain four aspects on the performance of students: the adherence to the experimental procedures, the depth of participation in experiment, the quality of experiment report, and the mastery of experiment principles and skills, which account for 10 %, 20 %, 40 % and 30 % in the total scores, respectively. All four aspects were graded quantitatively. This evaluation system has been tested in our experiment teaching. The results suggest that it has an effect on the promotion of teaching in genetics experiments.

Beneficial uses of 241Am

International Nuclear Information System (INIS)

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

1984-05-01

This report assesses the uses of 241 Am and the associated costs and supply. The study shows that 241 Am-fueled radioisotope thermoelectric generators in the range of 1 to 5 W electrical provide the most promising use of kilogram amounts of this isotope. For medical uses, where purity is essential, irradiation of 241 Am can produce 97% pure 238 Pu at $21,000/g. Using a pyro-metallurgical process, 241 Am could be recovered from molten salt extraction (MSE) residues at an estimated incremental cost of $83/g adjusted to reflect the disposal costs of waste products. This cost of recovery is less than the $300/g cost for disposal of the 241 Am contained in the MSE residues

Open source identity management patterns and practices using OpenAM 10.x

CERN Document Server

Kenning, Waylon

2013-01-01

This is a Packt Mini in a tutorial format that provides multiple examples on Identity Management using OpenAM 10.x.Open Source Identity Management Patterns and Practices Using OpenAM 10.x is great for developers and architects who are new to Identity Management, and who want a brief overview of what's possible and how to quickly implement a prototype. It's assumed that you've had experience with web applications and some knowledge of Apache and Tomcat.

Nickel remediation by AM-colonized sunflower.

Science.gov (United States)

Ker, Keomany; Charest, Christiane

2010-08-01

This greenhouse study aimed to examine the contribution of arbuscular mycorrhizal (AM) colonization on the uptake of and tolerance to nickel (Ni) in sunflower (Helianthus annuus L.). We hypothesized that AM colonization increases Ni content and tolerance in sunflower grown under varying soil Ni concentrations. The combined effect of AM colonization and soil Ni input on the assimilation of nitrogen, in particular the activity of glutamine synthetase (GS), in sunflower plants was also investigated. A factorial experimental design was performed with sunflower cv. Lemon Queen, with or without the AM fungus, Glomus intraradices Schenck & Smith, and treated with 0, 100, 200, or 400 mg Ni kg(-1) dry soil (DS). The AM colonization significantly enhanced plant growth and Ni content, especially at the lower soil Ni treatments. Furthermore, the AM plants exposed to the highest soil Ni level of 400 mg Ni kg(-1) DS had a significantly higher shoot Ni extracted percentage than non-AM plants, suggesting that the AM symbiosis contributed to Ni uptake, then its translocation from roots to shoots. The AM colonization also significantly increased the GS activity in roots, this being likely an indicator of an enhanced Ni tolerance. These findings support the hypothesis that AM symbiosis contributes to an enhanced Ni plant uptake and tolerance and should be considered as part of phytoremediation strategies.

Evaluation of neutron nuclear data for 241Am and 243Am

International Nuclear Information System (INIS)

Kikuchi, Yasuyuki

1982-08-01

Neutron nuclear data of 241 Am and 243 Am were evaluated for JENDL-2. Evaluated quantities are the total, elastic and inelastic scattering, fission, capture, (n,2n), (n,3n) and (n,4n) reaction cross sections, the resolved and unresolved resonance parameters, the angular or energy distribution of the emitted neutrons, and the average number of neutrons emitted per fission. The fission cross section was evaluated on the basis of newly measured data, and lower values than JENDL-1 were given in the subthreshold energy region. The reliability of the calculation parameters are also much improved, because experimental data became available for the total and capture cross sections of 241 Am in the high energy region. (author)

Test Management Framework for the ATLAS Experiment

CERN Document Server

Kazarov, Andrei; The ATLAS collaboration; Avolio, Giuseppe

2018-01-01

Test Management Framework for the Data Acquisition of the ATLAS Experiment Data Acquisition (DAQ) of the ATLAS experiment is a large distributed and inhomogeneous system: it consists of thousands of interconnected computers and electronics devices that operate coherently to read out and select relevant physics data. Advanced diagnostics capabilities of the TDAQ control system are a crucial feature which contributes significantly to smooth operation and fast recovery in case of the problems and, finally, to the high efficiency of the whole experiment. The base layer of the verification and diagnostic functionality is a test management framework. We have developed a flexible test management system that allows the experts to define and configure tests for different components, indicate follow-up actions to test failures and describe inter-dependencies between DAQ or detector elements. This development is based on the experience gained with the previous test system that was used during the first three years of th...

Thermoresponsive behaviour of AM2O8 materials

International Nuclear Information System (INIS)

Allen, Simon

2003-01-01

This thesis investigates the synthesis and structural characterisation of AM 2 O 8 phases, many of which show negative thermal expansion (NTE); relevant literature is reviewed in Chapter One. Chapter Two describes the synthesis, structure solution, and mechanistic role of a new family of low-temperature (LT) orthorhombic AM 2 O 8 polymorphs (A IV = Zr, Hf; M VI = Mo, W). These materials are key intermediates in the preparation of cubic AM 2 O 8 phases from AM 2 O 7 (OH) 2 (H 2 O) 2 . The structure of LT-AM 2 O 8 has been elucidated by combined laboratory X-ray and neutron powder diffraction. Variable temperature X-ray diffraction (VTXRD) studies have shown LT-AMo 2 O 8 phases exhibit anisotropic NTE. LT-ZrMo 2 O 8 has been shown to undergo spontaneous rehydration, allowing preparation of ZrMo 2 O 7 (OD) 2 (D 2 O) 2 and assignment of D 2 O/OD positions within the structure by neutron diffraction. Using this result, a reversible topotactic dehydration pathway from AM 2 O 7 (OH) 2 (H 2 O) 2 to LT-AM 2 O 8 is proposed. Chapter Three investigates the order-disorder phase transition with concurrent oxygen mobility in cubic AM 2 O 8 materials; studies include comprehensive VT neutron diffraction of cubic ZrMo 2 O 8 to reveal a static to dynamic transition at 215 K, and novel quench-anneal/quench-warm variable temperature/time diffraction experiments on ZrWMoO 8 which lead to an activation energy of 40 kJmol -1 for oxygen migration. In Chapter Four 17 O-labelled cubic ZrW 2 O 8 has been prepared to understand the oxygen migration process by VT MAS NMR. In situ hydrothermal studies of cubic ZrMo 2 O 8 using synchrotron radiation have shown direct hydration to ZrMo 2 O 7 (OH) 2 (H 2 O) 2 . In Chapter Five VTXRD of trigonal α-AMo 2 O 8 phases reveals a previously unknown second-order phase transition at 487 K (A = Zr) or 463 K (A = Hf) from P3-bar 1c to P3-bar m1. Rigid-body Rietveld refinements have shown this is due to alignment of apical Mo-O groups with the c axis in the

Effect of alcohol on internally deposited Am-241 in the baboon: a pilot study

International Nuclear Information System (INIS)

Cohen, N.; Antonelli, R.; LoSasso, T.

1977-01-01

The efficacy of ethyl alcohol in enhancing the excretion of Am-241 from the baboon has been tested. Alcohol enhances Am-241 excretion via the fecal route by a factor of about 2.5. However, there is a corresponding increase in fecal volume, and no significant change in the concentration of the nuclide in the feces. Other cathartics tested caused increased fecal volumes with no change in amount of activity excreted leading to a decreased concentration of the nuclide in the feces. Alcohol is not as effective as DTPA in removing Am-241 from the body. Preliminary results suggest that alcohol has little or no enhancement effect on the decorporation capability of DTPA

The testing effect for mediator final test cues and related final test cues in online and laboratory experiments.

Science.gov (United States)

Coppens, Leonora C; Verkoeijen, Peter P J L; Bouwmeester, Samantha; Rikers, Remy M J P

2016-05-31

The testing effect is the finding that information that is retrieved during learning is more often correctly retrieved on a final test than information that is restudied. According to the semantic mediator hypothesis the testing effect arises because retrieval practice of cue-target pairs (mother-child) activates semantically related mediators (father) more than restudying. Hence, the mediator-target (father-child) association should be stronger for retrieved than restudied pairs. Indeed, Carpenter (2011) found a larger testing effect when participants received mediators (father) than when they received target-related words (birth) as final test cues. The present study started as an attempt to test an alternative account of Carpenter's results. However, it turned into a series of conceptual (Experiment 1) and direct (Experiment 2 and 3) replications conducted with online samples. The results of these online replications were compared with those of similar existing laboratory experiments through small-scale meta-analyses. The results showed that (1) the magnitude of the raw mediator testing effect advantage is comparable for online and laboratory experiments, (2) in both online and laboratory experiments the magnitude of the raw mediator testing effect advantage is smaller than in Carpenter's original experiment, and (3) the testing effect for related cues varies considerably between online experiments. The variability in the testing effect for related cues in online experiments could point toward moderators of the related cue short-term testing effect. The raw mediator testing effect advantage is smaller than in Carpenter's original experiment.

Cannabinoid type 1 receptor ligands WIN 55,212-2 and AM 251 alter anxiety-like behaviors of marmoset monkeys in an open-field test.

Science.gov (United States)

Cagni, Priscila; Barros, Marilia

2013-03-01

Cannabinoid type 1 receptors (CB1r) are an important modulatory site for emotional behavior. However, little is known on the effects of CB1r ligands on emotionality aspects of primates, even with their highly similar behavioral response and receptor density/distribution as humans. Thus, we analyzed the effects of the CB1r agonist WIN 55,212-2 (WIN; 1mg/kg) and the antagonist AM 251 (AM; 2mg/kg), systemically administered prior to a single brief (15 min) exposure to a novel open-field (OF) environment, on the behavior of individually tested adult black tufted-ear marmosets. Both WIN- and AM-treated subjects, compared to vehicle controls, had significantly lower rates of long (contact) calls and exploration, while higher levels of vigilance-related behaviors (scan/glance); these are indicators of anxiolysis in this setup. Changes in locomotion were not detected. However, in the vehicle and AM-groups, sojourn in the peripheral zone of the OF was significantly higher than in its central region. WIN-treated marmosets spent an equivalent amount of time in both zones. Therefore, activation or blockade CB1r function prior to a short and individual exposure to an unfamiliar environment exerted a significant and complex influence on different behavioral indicators of anxiety in these monkeys (i.e., a partially overlapping anxiolytic-like profile). AM 251, however, has no anxiolytic effect when the time spent in the center of the OF is considered. This is a major difference when compared to the WIN-treated group. Data were compared to the response profile reported in other pre-clinical (rodent) and clinical studies. Copyright © 2012 Elsevier B.V. All rights reserved.

Disturbance from Am-241 Photons of the Cellular Dose by Am-241 Alpha Emissions: Am-241 as an alternative source of alpha particles to radon daughters

International Nuclear Information System (INIS)

Lee, Ki-Man; Kim, Eun-Hee

2015-01-01

The Radiation Bioengineering Laboratory (RadBio Lab) at Seoul National University (SNU) has built an Am-241 alpha particle irradiator for study of cellular responses to radiation from radon daughters. The radon daughters of concern that cause internal exposure from inhalation of radon-contaminated air are Po-218, Po-214 and Po-210. In their alpha decay schemes, the yields of photon emissions are negligible. Unfortunately, Am-241, the source of alpha irradiator in RadBio Lab, emits photons at every alpha decay while transforming to Np-237 of long half-life. Employing Am-241 as the source simulating radon daughters, therefore, requires that photon emissions from Am-241 be specified in term of dose contribution. In this study, Monte Carlo calculations have been made to characterize dose contributions of Am-241 photon emissions. This study confirms that disturbance from Am-241 photon emissions of the cellular dose by Am-241 alpha emissions is negligible. Dose contamination fraction from photon emissions was 8.02 .. 10 -6 at 25 mm SSD at maximum. Also, note that LET in tissue-equivalent medium varies within about 20% for alpha particles at energies over 5 MeV

Extraction Separation of Am(III) and Eu(III) with Thermo-sensitive Gel introducing TPEN Derivatives

International Nuclear Information System (INIS)

Kenji Takeshita; Yoshio Nakano; Tatsuro Matsumura; Atsunori Mori

2008-01-01

A thermal-swing chromatographic process using a thermo-sensitive gel co-polymerized with NIPA (N-isopropyl-acrylamide) and TPPEN (N,N,N',N'-tetrakis(4-propenyl-oxy-2-pyridyl-methyl)ethylenediamine) was studied for the separation of Am(III) from Eu(III). First, the radiolysis of the TPPEN-NIPA gel was tested by the γ-ray irradiation and the α nuclide adsorption. The extraction separation of Am(III) was not influenced in the radioactive environment of the proposed process. Next, the TPPEN-NIPA gel was immobilized in porous silica particles and the applicability of the gel-immobilized silica to the proposed process was tested. Am(III) was extracted selectively in the gel-immobilized silica at 5 deg. C and the separation factor of Am(III) over Eu(III) was evaluated to be 3.7. The distribution ratio of Am(III) was reduced to less than 1/20 by increasing temperature from 5 deg. C to 40 deg. C. These results indicate that the TPPEN-NIPA gel is applicable to the thermal-swing chromatographic process for the minor actinide recovery. (authors)

A test of the functional avoidance hypothesis in the development of overgeneral autobiographical memory.

Science.gov (United States)

Hallford, D J; Austin, D W; Raes, F; Takano, K

2018-04-18

Overgeneral memory (OGM) refers to the failure to recall memories of specific personally experienced events, which occurs in various psychiatric disorders. One pathway through which OGM is theorized to develop is the avoidance of thinking of negative experiences, whereby cumulative avoidance may maladaptively generalize to autobiographical memory (AM) more broadly. We tested this, predicting that negative experiences would interact with avoidance to predict AM specificity. In Study 1 (N = 281), negative life events (over six months) and daily hassles (over one month) were not related to AM specificity, nor was avoidance, and no interaction was found. In Study 2 (N = 318), we revised our measurements and used an increased timeframe of 12 months for both negative life events and daily hassles. The results showed no interaction effect for negative life events, but they did show an interaction for daily hassles, whereby increased hassles and higher avoidance of thinking about them were associated with reduced AM specificity, independent of general cognitive avoidance and depressive symptoms. No evidence was found that cognitive avoidance or AM specificity moderated the effect of negative experiences on depressive symptoms. Our findings suggest that life events over 6-12 months are not associated with AM specificity, but chronic daily hassles over 12 months predict reduced AM specificity when individuals avoid thinking about them. The findings provide evidence for the functional-avoidance hypothesis of OGM development and future directions for longitudinal studies.

Accumulation of {sup 241}Am by suspended matter, diatoms and aquatic weeds of the Yenisei River

Energy Technology Data Exchange (ETDEWEB)

Zotina, T.A., E-mail: t_zotina@ibp.r [Institute of Biophysics SB RAS, Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Bolsunovsky, A.Ya.; Bondareva, L.G. [Institute of Biophysics SB RAS, Akademgorodok, Krasnoyarsk 660036 (Russian Federation)

2010-02-15

In this work we experimentally estimated the capacities of the key components of the Yenisei River (Russia): particulate suspended matter (seston), diatom microalgae, and submerged macrophytes for accumulating {sup 241}Am from water. In our experiments large particles of seston (>8 mum), comparable in size with diatoms, took up most of americium from water. The accumulation of americium by isolated diatom algae (Asterionella formosa and Diatoma vulgare) was lower than by total seston. The concentration factors (CFs) of {sup 241}Am for seston of the Yenisei River in our experiments were (2.8-6.9).10{sup 5}; for diatoms - (1.5-4.2).10{sup 4}. The CFs for aquatic plant Elodea canadensis were within the same order of magnitude as those for diatoms. Activity concentration and CFs of {sup 241}Am were nearly the same in experiments under dark and light conditions. This is indicative of an energy independent mechanism of americium uptake from the water by diatoms and submerged macrophytes.

AMS in drug development at GSK

International Nuclear Information System (INIS)

Young, G.C.; Ellis, W.J.

2007-01-01

A history of the use of AMS in GSK studies spanning the last 8 years (1998-2005) is presented, including use in pilot studies through to clinical, animal and in vitro studies. A brief summary of the status of GSK's in-house AMS capability is outlined and views on the future of AMS in GSK are presented, including potential impact on drug development and potential advances in AMS technology

Power-Cooling-Mismatch Test Series Test PCM-7. Experiment operating specifications

International Nuclear Information System (INIS)

Sparks, D.T.; Smith, R.H.; Stanley, C.J.

1979-02-01

The experiment operating specifications for the Power-Cooling-Mismatch (PCM) Test PCM-7 to be conducted in the Power Burst Facility are described. The PCM Test Series was designed on the basis of a parametric evaluation of fuel behavior response with cladding temperature, rod internal pressure, time in film boiling, and test rod power being the variable parameters. The test matrix, defined in the PCM Experiment Requirements Document (ERD), encompasses a wide range of situations extending from pre-CHF (critical heat flux) PCMs to long duration operation in stable film boiling leading to rod failure

AMS Radiocarbon Dating at Notre Dame

Science.gov (United States)

Howard, Sean

2014-09-01

Current development of a local radiocarbon dating method using Accelerator Mass Spectrometry (AMS) at the University of Notre Dame seeks to provide sensitive, reproducible, and accurate measurements for future interdisciplinary projects. While AMS has been the premier radiocarbon dating method for a few decades, repurposing Notre Dame's FN Tandem accelerator for radiocarbon dating has provided many unique challenges. Experiments have shown radiocarbon dating possible and reproducible using the FN Tandem accelerator, found optimal settings for said accelerator, and established sensitivity limits comparable to dedicated radiocarbon dating facilities. In addition, there is ongoing work to create a local chemistry lab to convert organic artifacts into graphite samples to be dated locally. Once the chemistry side has been completed, several artifacts from the IAEA's radiocarbon intercomparison have been procured. Dating these previously studied artifacts will provide an additional measure on the accuracy and repeatability of both the accelerator and chemical treatment. Provided that these IAEA artifacts are dated successfully, exciting projects will ensue, such as the authentication of artwork and dating of anthropological samples.

Small Payload Launch Integrated Testing Services (SPLITS) - SPSDL

Science.gov (United States)

Plotner, Benjamin

2013-01-01

My experience working on the Small Payload Launch Integrated Testing Services project has been both educational and rewarding. I have been given the opportunity to work on and experiment with a number of exciting projects and initiatives, each offering different challenges and opportunities for teamwork and collaboration. One of my assignments is to aid in the design and construction of a small-scale two stage rocket as part of a Rocket University initiative. My duties include programming a microcontroller to control the various sensors on the rocket as well as process and transmit data. Additionally, I am writing a graphical user interface application for the ground station that will receive the transmitted data from the rocket and display the information on screen along with a 3D rendering displaying the rocket orientation. Another project I am working on is to design and develop the avionics that will be used to control a high altitude balloon flight that will test a sensor called a Micro Dosimeter that will measure the total ionizing dose absorbed by electrical components during a flight. This includes assembling and soldering the various sensors and components, programming a microcontroller to input and process data from the Micro Dosimeter, and transmitting the data down to a ground station as well as save the data to an on-board SD card. Additionally, I am aiding in the setup and development of ITOS (Integrated Test and Operations System) capability in the SPSDL (Spaceport Processing System Development Lab).

AMS analyses at ANSTO

Energy Technology Data Exchange (ETDEWEB)

Lawson, E.M. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia). Physics Division

1998-03-01

The major use of ANTARES is Accelerator Mass Spectrometry (AMS) with {sup 14}C being the most commonly analysed radioisotope - presently about 35 % of the available beam time on ANTARES is used for {sup 14}C measurements. The accelerator measurements are supported by, and dependent on, a strong sample preparation section. The ANTARES AMS facility supports a wide range of investigations into fields such as global climate change, ice cores, oceanography, dendrochronology, anthropology, and classical and Australian archaeology. Described here are some examples of the ways in which AMS has been applied to support research into the archaeology, prehistory and culture of this continent`s indigenous Aboriginal peoples. (author)

AMS analyses at ANSTO

International Nuclear Information System (INIS)

Lawson, E.M.

1998-01-01

The major use of ANTARES is Accelerator Mass Spectrometry (AMS) with 14 C being the most commonly analysed radioisotope - presently about 35 % of the available beam time on ANTARES is used for 14 C measurements. The accelerator measurements are supported by, and dependent on, a strong sample preparation section. The ANTARES AMS facility supports a wide range of investigations into fields such as global climate change, ice cores, oceanography, dendrochronology, anthropology, and classical and Australian archaeology. Described here are some examples of the ways in which AMS has been applied to support research into the archaeology, prehistory and culture of this continent's indigenous Aboriginal peoples. (author)

Determination of Pu, Am and Cm in Environmental Samples

Energy Technology Data Exchange (ETDEWEB)

Lujaniene, G. [SRI Centre for Physical Sciences and Technology, Vilnius (Lithuania)

2013-07-15

The determination of actinides in the environmental samples at a lower detection limit is required for monitoring purposes and for environmental research. The method for Pu, Am and Cm measurements in soil and sediment samples provides high recoveries and good decontamination from interfering radionuclides. The main steps of the method involve digestion of the samples, separation of radionuclides from matrix using the TOPO /cyclohexane extraction and final purification using extraction Eichrom resins (TEVA, TRU). The accuracy and precision of Pu, Am and Cm analyses were tested using IAEA RM No 135, NIST SRM No 4350b, No 4357 and in intercomparison runs organized by the Riso National Laboratory, Denmark, and in the proficiency tests organized by National Physical Laboratory, UK. The method was applied for measurement of radionuclides in aerosol samples (ashes {approx}30 g), bottom sediments (50-80 g dr. wt) and soil (including Chernobyl soil) samples. (author)

Is 8:30 a.m. Still Too Early to Start School? A 10:00 a.m. School Start Time Improves Health and Performance of Students Aged 13–16

Directory of Open Access Journals (Sweden)

Paul Kelley

2017-12-01

Full Text Available While many studies have shown the benefits of later school starts, including better student attendance, higher test scores, and improved sleep duration, few have used starting times later than 9:00 a.m. Here we report on the implementation and impact of a 10 a.m. school start time for 13 to 16-year-old students. A 4-year observational study using a before-after-before (A-B-A design was carried out in an English state-funded high school. School start times were changed from 8:50 a.m. in study year 0, to 10 a.m. in years 1–2, and then back to 8:50 a.m. in year 3. Measures of student health (absence due to illness and academic performance (national examination results were used for all students. Implementing a 10 a.m. start saw a decrease in student illness after 2 years of over 50% (p < 0.0005 and effect size: Cohen's d = 1.07, and reverting to an 8:50 a.m. start reversed this improvement, leading to an increase of 30% in student illness (p < 0.0005 and Cohen's d = 0.47. The 10:00 a.m. start was associated with a 12% increase in the value-added number of students making good academic progress (in standard national examinations that was significant (<0.0005 and equivalent to 20% of the national benchmark. These results show that changing to a 10:00 a.m. high school start time can greatly reduce illness and improve academic performance. Implementing school start times later than 8:30 a.m., which may address the circadian delay in adolescents' sleep rhythms more effectively for evening chronotypes, appears to have few costs and substantial benefits.

Insight into the Am-O Phase Equilibria: A Thermodynamic Study Coupling High-Temperature XRD and CALPHAD Modeling.

Science.gov (United States)

Epifano, Enrica; Guéneau, Christine; Belin, Renaud C; Vauchy, Romain; Lebreton, Florent; Richaud, Jean-Christophe; Joly, Alexis; Valot, Christophe; Martin, Philippe M

2017-07-03

In the frame of minor actinide transmutation, americium can be diluted in UO 2 and (U, Pu)O 2 fuels burned in fast neutron reactors. The first mandatory step to foresee the influence of Am on the in-reactor behavior of transmutation targets or fuel is to have fundamental knowledge of the Am-O binary system and, in particular, of the AmO 2-x phase. In this study, we coupled HT-XRD (high-temperature X-ray diffraction) experiments with CALPHAD thermodynamic modeling to provide new insights into the structural properties and phase equilibria in the AmO 2-x -AmO 1.61+x -Am 2 O 3 domain. Because of this approach, we were able for the first time to assess the relationships between temperature, lattice parameter, and hypostoichiometry for fcc AmO 2-x . We showed the presence of a hyperstoichiometric existence domain for the bcc AmO 1.61+x phase and the absence of a miscibility gap in the fcc AmO 2-x phase, contrary to previous representations of the phase diagram. Finally, with the new experimental data, a new CALPHAD thermodynamic model of the Am-O system was developed, and an improved version of the phase diagram is presented.

Am-241 buildup in nematode organisms

International Nuclear Information System (INIS)

Martyushov, V.Z.; Tarasov, O.V.

1990-01-01

The process of Am-241 intake into earthworm organisms from chernozem leached in their presence in soil contaminated with this radionuclide is studied. The data on Am-241 buildup values during long-time radionuclide intake into earthworm organisms from soil are given. It s shown that Am-241 buildup in earthworm organisms do not exceed its concentration in soil for the whole observation period (as Am-241 presents in soil in state unavailable for animals). Intensive extraction of the radionuclide from the organisms is observed when earthworm contacts with soil are stopped

FLOW TESTING AND ANALYSIS OF THE FSP-1 EXPERIMENT

Energy Technology Data Exchange (ETDEWEB)

Hawkes, Grant L.; Jones, Warren F.; Marcum, Wade; Weiss, Aaron; Howard, Trevor

2017-06-01

The U.S. High Performance Research Reactor Conversions fuel development team is focused on developing and qualifying the uranium-molybdenum (U-Mo) alloy monolithic fuel to support conversion of domestic research reactors to low enriched uranium. Several previous irradiations have demonstrated the favorable behavior of the monolithic fuel. The Full Scale Plate 1 (FSP-1) fuel plate experiment will be irradiated in the northeast (NE) flux trap of the Advanced Test Reactor (ATR). This fueled experiment contains six aluminum-clad fuel plates consisting of monolithic U-Mo fuel meat. Flow testing experimentation and hydraulic analysis have been performed on the FSP-1 experiment to be irradiated in the ATR at the Idaho National Laboratory (INL). A flow test experiment mockup of the FSP-1 experiment was completed at Oregon State University. Results of several flow test experiments are compared with analyses. This paper reports and shows hydraulic analyses are nearly identical to the flow test results. A water velocity of 14.0 meters per second is targeted between the fuel plates. Comparisons between FSP-1 measurements and this target will be discussed. This flow rate dominates the flow characteristics of the experiment and model. Separate branch flows have minimal effect on the overall experiment. A square flow orifice was placed to control the flowrate through the experiment. Four different orifices were tested. A flow versus delta P curve for each orifice is reported herein. Fuel plates with depleted uranium in the fuel meat zone were used in one of the flow tests. This test was performed to evaluate flow test vibration with actual fuel meat densities and reported herein. Fuel plate deformation tests were also performed and reported.

Recent advances in AM OLED technologies for application to aerospace and military systems

Science.gov (United States)

Sarma, Kalluri R.; Roush, Jerry; Chanley, Charles

2012-06-01

While initial AM OLED products have been introduced in the market about a decade ago, truly successful commercialization of OLEDs has started only a couple of years ago, by Samsung Mobile Display (SMD), with small high performance displays for smart phone applications. This success by Samsung has catalyzed significant interest in AM OLED technology advancement and commercialization by other display manufacturers. Currently, significant manufacturing capacity for AM OLED displays is being established by the industry to serve the growing demand for these displays. The current development in the AM OLED industry are now focused on the development and commercialization of medium size (~10") AM OLED panels for Tablet PC applications and large size (~55") panels for TV applications. This significant progress in commercialization of AM OLED technology is enabled by major advances in various enabling technologies that include TFT backplanes, OLED materials and device structures and manufacturing know-how. In this paper we will discuss these recent advances, particularly as they relate to supporting high performance applications such as aerospace and military systems, and then discuss the results of the OLED testing for aerospace applications.

Application and testing of additive manufacturing for mirrors and precision structures

Science.gov (United States)

Sweeney, Michael; Acreman, Martyn; Vettese, Tom; Myatt, Ray; Thompson, Mike

2015-09-01

Additive Manufacturing (aka AM, and 3-D printing) is widely touted in the media as the foundation for the next industrial revolution. Beneath the hype, AM does indeed offer profound advantages in lead-time, dramatically reduced consumption of expensive raw materials, while enabling new and innovative design forms that cannot be produced by other means. General Dynamics and their industry partners have begun to embrace this technology for mirrors and precision structures used in the aerospace, defense, and precision optical instrumentation industries. Aggressively lightweighted, open and closed back test mirror designs, 75-150 mm in size, were first produced by AM from several different materials. Subsequent optical finishing and test experiments have exceeded expectations for density, surface finish, dimensional stability and isotropy of thermal expansion on the optical scale of measurement. Materials currently under examination include aluminum, titanium, beryllium, aluminum beryllium, Inconel 625, stainless steel/bronze, and PEKK polymer.

The construction and space qualification of the control electronics for the tracker detector cooling system of the AMS-02 experiment

International Nuclear Information System (INIS)

Menichelli, M.; Accardo, L.; Alberti, G.; Bardet, M.; Battiston, R.; Blasko, S.; He, Z.; Koutsenko, V.; Lebedev, A.; Ni, J.; Papi, A.; Pauw, A.; Van Ess, J.; Wang, Z.; Zhang, D.; Zwartbol, T.

2010-01-01

This article describes the control electronics for the silicon tracker cooling system in the AMS-02 apparatus. It also contains a brief description of the cooling system itself necessary for the description of the electronics. The tracker cooling system includes a set of various sensors and actuators which are necessary for bringing the tracker detector to a uniform temperature at which it can operate correctly. In order to test the system performing the various qualification activities we have built also an Electronic Ground support equipment (EGSE). The EGSE should simulate the behaviour of all sensors and actuators previously mentioned.

A small and compact AMS facility for tritium depth profiling

Indian Academy of Sciences (India)

Depth profiling measurements of tritium in carbon samples have been performed during the past seven years at the AMS facility installed at the Rossendorf 3 MV Tandetron. The samples have been cut from the inner walls of the fusion experiments ASDEX-upgrade/Garching and JET/Culham. The tritium content of the ...

Innovative Instructional Tools from the AMS

Science.gov (United States)

Abshire, W. E.; Geer, I. W.; Mills, E. W.; Nugnes, K. A.; Stimach, A. E.

2016-12-01

Since 1996, the American Meteorological Society (AMS) has been developing online educational materials with dynamic features that engage students and encourage additional exploration of various concepts. Most recently, AMS transitioned its etextbooks to webBooks. Now accessible anywhere with internet access, webBooks can be read with any web browser. Prior versions of AMS etextbooks were difficult to use in a lab setting, however webBooks are much easier to use and no longer a hurdle to learning. Additionally, AMS eInvestigations Manuals, also in webBook format, include labs with innovative features and educational tools. One such example is the AMS Climate at a Glance (CAG) app that draws data from NOAA's Climate at a Glance website. The user selects historical data of a given parameter and the app calculates various statistics revealing whether or not the results are consistent with climate change. These results allow users to distinguish between climate variability and climate change. This can be done for hundreds of locations across the U.S. and on multiple time scales. Another innovative educational tool used in AMS eInvestigations Manuals is the AMS Conceptual Climate Energy Model (CCEM). The CCEM is a computer simulation designed to enable users to track the paths that units of energy might follow as they enter, move through and exit an imaginary system according to simple rules applied to different scenarios. The purpose is to provide insight into the impacts of physical processes that operate in the real world. Finally, AMS educational materials take advantage of Google Earth imagery to reproduce the physical aspects of globes, allowing users to investigate spatial relationships in three dimensions. Google Earth imagery is used to explore tides, ocean bottom bathymetry and El Nino and La Nina. AMS will continue to develop innovative educational materials and tools as technology advances, to attract more students to the Earth sciences.

Modeling and flowsheet design of an Am separation process using TODGA and H{sub 4}TPAEN

Energy Technology Data Exchange (ETDEWEB)

Vanel, V.; Marie, C.; Montuir, M.; Boubals, N.; Sorel, C. [CEA, Centre de Marcoule, Nuclear Energy Division, Radiochemistry and Processes Department, Bagnols-sur-Ceze, F-30207 (France); Kaufholz, P.; Modolo, G. [Forschungszentrum Juelich GmbH, Institute of Energy and Climate Research, Nuclear Waste Management and Reactor Safety, D-52428 (Germany); Geist, A. [Karlsruher Institut fuer Technologie - KIT, Institut fuer Nukleare Entsorgung - INE, Karlsruhe (Germany)

2016-07-01

Recycling americium from spent fuels is an important consideration for the future nuclear fuel cycle, as americium is the main contributor to the long-term radiotoxicity and heat power of the final waste, after separation of uranium and plutonium using the PUREX process. The separation of americium alone from a PUREX raffinate can be achieved by co-extracting lanthanide (Ln(III)) and actinide (An(III)) cations into an organic phase containing the diglycolamide extractant TODGA, and then stripping Am(III) with selectivity towards Cm(III) and lanthanides. The water soluble ligand H{sub 4}TPAEN was tested to selectively strip Am from a loaded organic phase. Based on experimental data obtained by Juelich, NNL and CEA laboratories since 2013, a phenomenological model has been developed to simulate the behavior of americium, curium and lanthanides during their extraction by TODGA and their complexation by H{sub 4}TPAEN (complex stoichiometry, extraction and complexation constants, kinetics). The model was gradually implemented in the PAREX code and helped to narrow down the best operating conditions. Thus, the following 2 modifications of initial operating conditions were proposed: -) an increase in the concentration of TPAEN as much as the solubility limit allows, and -) an improvement of the lanthanide scrubbing from the americium flow by adding nitrates to the aqueous phase. A qualification of the model was begun by comparing on the one hand constants determined with the model to those measured experimentally, and on the other hand, simulation results and experimental data on new independent batch experiments. A first sensitivity analysis identified which parameter has the most dominant effect on the process. A flowsheet was proposed for a spiked test in centrifugal contactors performed with a simulated PUREX raffinate with trace amounts of Am and Cm. If the feasibility of the process is confirmed, the results of this test will be used to consolidate the model and to

AMS/DOE Fellowship Recipients

Energy Technology Data Exchange (ETDEWEB)

Armstrong, Stephanie [American Meteorological Society, Boston, MA (United States)

2016-11-21

The AMS/DOE graduate fellowships were awarded to three students entering their first year of graduate study. The funds allowed each student to take a full course load during their first of year of graduate study which helps each of them to enter the professional, scientific community at an earlier date. Each recipient is academically outstanding, received glowing references of support and demonstrated their strong desire to perform scientific research. As part of the fellowship, each of the students was invited to attend the AMS Annual Meeting where they got to participate in the AMS student conference, attend scientific sessions and visit the exhibition hall. In addition, a student awards luncheon was held where each of the recipients got to meet their sponsor and receive a certificate.

80 kV electrostatic wire septum for AmPS

International Nuclear Information System (INIS)

Linden, A. van der; Bijleveld, J.H.M.; Rookhuizen, H.B.; Bruinsma, P.J.T.; Heine, E.; Lassing, P.; Prins, E.

1992-01-01

The Amsterdam Pulse Stretcher (AmPS) ring aims at a 100% duty cycle operation by means of slow extraction of injected electron beam pulses of 2.1 μs. In the extraction process of the AmPS, the extracted beam is intercepted from the circulating beam by the 1 m long electrostatic wire septum. For a bending angle of 4.4 mrad the maximum anode voltage is 80 kV. Care has been given to the electric field distribution at the entrance and exit of the septum and to the insulators, required to support the anode. Prototype tests have been successful up to an anode voltage of 120 kV. (R.P.) 9 refs.; 5 figs

Led spectral and power characteristics under hybrid PWM/AM dimming strategy

DEFF Research Database (Denmark)

Beczkowski, Szymon; Munk-Nielsen, Stig

2010-01-01

In order to dim LEDs the pulse width modulation (PWM) or amplitude modulation (AM) dimming scheme is typically used. Previous studies show that these dimming schemes can have opposite effects on diodes peak wavelength shift. An experimental study was conducted to test the behavior of InGaN diodes...... and phosphor-converted white diodes under hybrid PWM/AM modulation. Feed forward control schemes that provide stable peak wavelength position during dimming and the ability to compensate the thermally induced color shifts and the decrease of the luminous flux are investigated....

Real-time detection of natural objects using AM-coded spectral matching imager

Science.gov (United States)

Kimachi, Akira

2005-01-01

This paper describes application of the amplitude-modulation (AM)-coded spectral matching imager (SMI) to real-time detection of natural objects such as human beings, animals, vegetables, or geological objects or phenomena, which are much more liable to change with time than artificial products while often exhibiting characteristic spectral functions associated with some specific activity states. The AM-SMI produces correlation between spectral functions of the object and a reference at each pixel of the correlation image sensor (CIS) in every frame, based on orthogonal amplitude modulation (AM) of each spectral channel and simultaneous demodulation of all channels on the CIS. This principle makes the SMI suitable to monitoring dynamic behavior of natural objects in real-time by looking at a particular spectral reflectance or transmittance function. A twelve-channel multispectral light source was developed with improved spatial uniformity of spectral irradiance compared to a previous one. Experimental results of spectral matching imaging of human skin and vegetable leaves are demonstrated, as well as a preliminary feasibility test of imaging a reflective object using a test color chart.

Integration and Testing Challenges of Small Satellite Missions: Experiences from the Space Technology 5 Project

Science.gov (United States)

Sauerwein, Timothy A.; Gostomski, Tom

2007-01-01

The Space Technology 5(ST5) payload was successfully carried into orbit on an OSC Pegasus XL launch vehicle, which was carried aloft and dropped from the OSC Lockheed L-1011 from Vandenberg Air Force Base March 22,2006, at 9:03 am Eastern time, 6:03 am Pacific time. In order to reach the completion of the development and successful launch of ST 5, the systems integration and test(I&T) team determined that a different approach was required to meet the project requirements rather than the standard I&T approach used for single, room-sized satellites. The ST5 payload, part of NASA's New Millennium Program headquartered at JPL, consisted of three micro satellites (approximately 30 kg each) and the Pegasus Support Structure (PSS), the system that connected the spacecrafts to the launch vehicle and deployed the spacecrafts into orbit from the Pegasus XL launch vehicle. ST5 was a technology demonstration payload, intended to test six (6) new technologies for potential use for future space flights along with demonstrating the ability of small satellites to perform quality science. The main technology was a science grade magnetometer designed to take measurements of the earth's magnetic field. The three spacecraft were designed, integrated, and tested at NASA Goddard Space Flight Center with integration and environmental testing occurring in the Bldg. 7-1 0-15-29. The three spacecraft were integrated and tested by the same I&T team. The I&T Manager determined that there was insufficient time in the schedule to perform the three I&T spacecraft activities in series used standard approaches. The solution was for spacecraft #1 to undergo integration and test first, followed by spacecraft #2 and #3 simultaneously. This simultaneous integration was successful for several reasons. Each spacecraft had a Lead Test Conductor who planned and coordinated their spacecraft through its integration and test activities. One team of engineers and technicians executed the integration of all

Electrochemical investigations of La, Nd and Am in molten chloride salts in view of Am/Ln partitioning

International Nuclear Information System (INIS)

Pernel, C.; Serp, J.; Ougier, M.; Malmbeck, R.; Glatz, J.P.

2001-01-01

The electrochemical behaviour of La, Nd and Am has been investigated in molten LiCl-KCl eutectic. La shows a reversible single reduction/oxidation step controlled by mass transfer. The electrochemical reduction of Nd and Am proceeds via a two steps process, i.e. the reduction of trivalent species (Nd(III) and Am(III)) leading to Nd(II) and Am(II) species which are reduced at more negative potentials to form metallic deposits. Diffusion coefficients of La, Nd and Am have been calculated and are in reasonable agreement with literature data. Electro-depositions of La and Nd have been carried out onto solid Ni and liquid Cd cathodes. Much higher deposition efficiency is obtained for La compared to Nd on a solid cathode. This is an effect of the multi-valent nature of Nd in the chloride melts. (author)

Electrochemical investigations of La, Nd and Am in molten chloride salts in view of Am/Ln partitioning

Energy Technology Data Exchange (ETDEWEB)

Pernel, C.; Serp, J.; Ougier, M.; Malmbeck, R.; Glatz, J.P. [European Commission, JRC, ITU, Karlsruhe (Germany)

2001-07-01

The electrochemical behaviour of La, Nd and Am has been investigated in molten LiCl-KCl eutectic. La shows a reversible single reduction/oxidation step controlled by mass transfer. The electrochemical reduction of Nd and Am proceeds via a two steps process, i.e. the reduction of trivalent species (Nd(III) and Am(III)) leading to Nd(II) and Am(II) species which are reduced at more negative potentials to form metallic deposits. Diffusion coefficients of La, Nd and Am have been calculated and are in reasonable agreement with literature data. Electro-depositions of La and Nd have been carried out onto solid Ni and liquid Cd cathodes. Much higher deposition efficiency is obtained for La compared to Nd on a solid cathode. This is an effect of the multi-valent nature of Nd in the chloride melts. (author)

Decay counting in the age of AMS

International Nuclear Information System (INIS)

Arnold, J.R.

1987-01-01

Up to the advent of AMS, all the accomplishments of 14 C dating, and the studies of 10 Be and other long-lived radionuclides, were made by low-level decay counting, the technique pioneered by W.F. Libby. It will hardly be news to people at this conference that, while much was accomplished in the three decades when counting prevailed, the world has now changed decisively. I will try to give an account of where low-level counting was 'before the revolution', and of what its usefulness is today. There are still some remarkable examples of its application, the best being the neutrino experiment of Raymond Davis, and its potential successors. Some cosmogenic nuclides, whose half-lives are less than 10 3 yr, are still best measured by decay; this will continue unless the overall ion yield of AMS systems rises markedly from present levels. One long-lived nuclide, 53 Mn, is still best measured by neutron activation as 312-day 54 Mn, but this may not continue. (orig.)

Decay counting in the age of AMS

International Nuclear Information System (INIS)

Arnold, J.R.

1987-01-01

Up to the advent of AMS, all the accomplishments of 14 C dating, and the studies of 10 Be and other long-lived radionuclides, were made by low-level decay counting, the technique pioneered by W.F. Libby. It will hardly be news to people at this conference that, while much was accomplished in the three decades when counting prevailed, the world has now changed decisively. He will try to give an account of where low-level counting was before the revolution, and of what its usefulness is today. There are still some remarkable examples of its application, the best being the neutrino experiment of Raymond Davis, and its potential successors. Some cosmogenic nuclides, whose half-lives are less than 10 3 yr, are still best measured by decay; this will continue unless the overall ion yield of AMS systems rises markedly from present levels. One long-lived nuclide, 53 Mn, is still best measured by neutron activation as 312-day 54 Mn, but this may not continue

Genomic and functional features of the biosurfactant producing Bacillus sp. AM13.

Science.gov (United States)

Shaligram, Shraddha; Kumbhare, Shreyas V; Dhotre, Dhiraj P; Muddeshwar, Manohar G; Kapley, Atya; Joseph, Neetha; Purohit, Hemant P; Shouche, Yogesh S; Pawar, Shrikant P

2016-09-01

Genomic studies provide deeper insights into secondary metabolites produced by diverse bacterial communities, residing in various environmental niches. This study aims to understand the potential of a biosurfactant producing Bacillus sp. AM13, isolated from soil. An integrated approach of genomic and chemical analysis was employed to characterize the antibacterial lipopeptide produced by the strain AM13. Genome analysis revealed that strain AM13 harbors a nonribosomal peptide synthetase (NRPS) cluster; highly similar with known biosynthetic gene clusters from surfactin family: lichenysin (85 %) and surfactin (78 %). These findings were substantiated with supplementary experiments of oil displacement assay and surface tension measurements, confirming the biosurfactant production. Further investigation using LCMS approach exhibited similarity of the biomolecule with biosurfactants of the surfactin family. Our consolidated effort of functional genomics provided chemical as well as genetic leads for understanding the biochemical characteristics of the bioactive compound.

Effect of arbuscular mycorrhizal (AM) fungi on 137Cs uptake by plants grown on different soils.

Science.gov (United States)

Vinichuk, M; Mårtensson, A; Ericsson, T; Rosén, K

2013-01-01

The potential use of mycorrhiza as a bioremediation agent for soils contaminated by radiocesium was evaluated in a greenhouse experiment. The uptake of (137)Cs by cucumber, perennial ryegrass, and sunflower after inoculation with a commercial arbuscular mycorrhizal (AM) product in soils contaminated with (137)Cs was investigated, with non-mycorrhizal quinoa included as a "reference" plant. The effect of cucumber and ryegrass inoculation with AM fungi on (137)Cs uptake was inconsistent. The effect of AM fungi was most pronounced in sunflower: both plant biomass and (137)Cs uptake increased on loamy sand and loamy soils. The total (137)Cs activity accumulated within AM host sunflower on loamy sand and loamy soils was 2.4 and 3.2-fold higher than in non-inoculated plants. Although the enhanced uptake of (137)Cs by quinoa plants on loamy soil inoculated by the AM fungi was observed, the infection of the fungi to the plants was not confirmed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of AMS procedure for measurement of 93Zr

Science.gov (United States)

Lu, Wenting; Collon, Philippe; Kashiv, Yoav; Bowers, Matthew; Robertson, Daniel; Schmitt, Christopher

2011-10-01

The procedure for measuring 93Zr (t1/2 = 1.5 Ma) by AMS is currently being developed at the Nuclear Science Lab at the University of Notre Dame and we report on first experiments performed in this direction. AMS detection of 93Zr can potentially be applied to address astrophysical and environmental issues: (1) the measurement of the 92Zr(n,γ)93Zr reaction cross-section at nucleosynthesis s-process relevant temperatures, (2) the search for potential live 93Zr from a supernova in deep sea sediments, (3) hydrological and radioactive waste tracing. The measurement of 93Zr requires adequate separation from its stable isobar 93Nb. We are currently working on optimizing this separation by using the GasFilled Magnet technique with additional multiple dE measurements in a focal plane ionization chamber.

The new 6 MV multi-nuclide AMS facility at the University of Tsukuba

Science.gov (United States)

Sasa, Kimikazu; Takahashi, Tsutomu; Matsumura, Masumi; Matsunaka, Tetsuya; Satou, Yukihiko; Izumi, Daiki; Sueki, Keisuke

2015-10-01

The former accelerator mass spectrometry (AMS) system installed on the 12UD Pelletron tandem accelerator at the University of Tsukuba was completely destroyed by the Great East Japan Earthquake on 11 March 2011. A replacement has been designed and constructed at the university as part of the post-quake reconstruction project. It consists of a 6 MV Pelletron tandem accelerator, two multiple cathode AMS ion sources (MC-SNICSs), and a rare-particle detection system. The 6 MV Pelletron tandem accelerator will be applied not only to AMS, but also to areas such as nanotechnology, ion beam analysis, heavy ion irradiation, and nuclear physics. The rare-particle detection system will be capable of measuring environmental levels of long-lived radioisotopes of 10Be, 14C, 26Al, 36Cl, 41Ca, and 129I. It is also expected to measure other radioisotopes such as 32Si and 90Sr. The 6 MV Pelletron tandem accelerator was installed in the spring of 2014 at the University of Tsukuba. Routine beam delivery and AMS experiments will start in 2015.

Charge determination of nuclei with the AMS-02 silicon tracker

CERN Document Server

Alpat, B; Azzarello, P; Battiston, R; Bene, P; Bertucci, B; Bizzaglia, S; Bizzarri, M; Blasko, S; Bourquin, M; Bouvier, P; Burger, W J; Capell, M; Cecchi, C; Chang, Y H; Cortina, E; Dinu, N; Esposito, G; Fiandrini, E; Haas, D; Hakobyan, H; Ionica, M; Ionica, R; Kounine, A; Koutsenko, V F; Lebedev, A; Lechanoine-Leluc, C; Lin, C H; Masciocchi, F; Menichelli, M; Natale, S; Paniccia, M; Papi, A; Pauluzzi, M; Perrin, E; Pohl, M; Rapin, D; Richeux, J P; Wallraff, W; Willenbrock, M; Zuccon, P

2005-01-01

The silicon tracker of the AMS-02 detector measures the trajectory in three dimensions of electrons, protons and nuclei to high precision in a dipole magnetic field and thus measures their rigidity (momentum over charge) and the sign of their charge. In addition, it measures the specific energy loss of charged particles to determine the charge magnitude. Ladders from the AMS-02 tracker have been exposed to ion beams at CERN and GSI to study their response to nuclei from helium up to the iron group. The longest ladder, 72 multiplied by 496mm2, verified in the tests contains 12 sensors. Good charge resolution is observed up to iron.

The microelectronics and photonics test bed (MPTB) space, ground test and modeling experiments

International Nuclear Information System (INIS)

Campbell, A.

1999-01-01

This paper is an overview of the MPTB (microelectronics and photonics test bed) experiment, a combination of a space experiment, ground test and modeling programs looking at the response of advanced electronic and photonic technologies to the natural radiation environment of space. (author)

Measurement of the 241Am and the 243Am Neutron Capture Cross Sections at the n_TOF Facility at CERN

CERN Document Server

Mendoza, E; Guerrero, C; Altstadt, S; Andrzejewski, J; Audouin, L; Barbagallo, M; Bécares, V; Bečvář, F; Belloni, F; Berthoumieux, E; Billowes, J; Boccone, V; Bosnar, D; Brugger, M; Calviani, M; Calviño, F; Carrapiço, C; Cerutti, F; Chiaveri, E; Chin, M; Colonna, N; Cortés, G; Cortés-Giraldo, M A; Diakaki, M; Domingo-Pardo, C; Duran, I; Dressler, R; Dzysiuk, N; Eleftheriadis, C; Ferrari, A; Fraval, K; Ganesan, S; García, A R; Giubrone, G; Gómez-Hornillos, M B; Gonçalves, I F; González-Romero, E; Griesmayer, E; Gunsing, F; Gurusamy, P; Jenkins, D G; Jericha, E; Kadi, Y; Käppeler, F; Karadimos, D; Kivel, N; Koehler, P; Kokkoris, M; Korschinek, G; Krtička, M; Kroll, J; Langer, C; Lederer, C; Leeb, H; Leong, L S; Losito, R; Manousos, A; Marganiec, J; Martínez, T; Mastinu, P F; Mastromarco, M; Massimi, C; Meaze, M; Mengoni, A; Milazzo, P M; Mingrone, F; Mirea, M; Mondelaers, W; Paradela, C; Pavlik, A; Perkowski, J; Pignatari, M; Plompen, A; Praena, J; Quesada, J M; Rauscher, T; Reifarth, R; Riego, A; Roman, F; Rubbia, C; Sarmento, R; Schillebeeckx, P; Schmidt, S; Schumann, D; Tagliente, G; Tain, J L; Tarrío, D; Tassan-Got, L; Tsinganis, A; Valenta, S; Vannini, G; Variale, V; Vaz, P; Ventura, A; Versaci, R; Vermeulen, M J; Vlachoudis, V; Vlastou, R; Wallner, A; Ware, T; Weigand, M; Weiß, C; Wright, T J; Žugec, P

2014-01-01

The capture cross sections of Am-241 and Am-243 were measured at the n\\_TOF facility at CERN in the epithermal energy range with a BaF2 Total Absorption Calorimeter. A preliminary analysis of the Am-241 and a complete analysis of the Am-243 measurement, including the data reduction and the resonance analysis, have been performed.

AM Fungi Influences the Photosynthetic Activity, Growth and Antioxidant Enzymes in Allium sativum L. under Salinity Condition

Directory of Open Access Journals (Sweden)

Mahesh BORDE

2010-12-01

Full Text Available Potential of Arbuscular mycorrhizal (AM fungi in alleviating adverse salt effects on growth was tested in garlic (Allium sativum L.. Towards this objective we analyzed the AM root colonization and the activities of various antioxidant enzymes like peroxidase, catalase, and superoxide dismutase at 0, 100, 200 and 300 mM salinity levels. The activities of all the antioxidant enzymes studied were found to be increased in AM garlic plants. Antioxidant activity was maximum in 100 and 200 mM NaCl (sodium chloride in AM and non-AM plants. Proline accumulation was induced by salt levels and it was more in leaves as well as roots of AM plants as compared to non-AM plants, this indicating that mycorrhiza reduced salt injury. Growth parameters of garlic plants like leaf area, plant fresh and dry weight and antioxidant enzyme activities were higher at moderate salinity level. This work suggests that the mycorrhiza helps garlic plants to perform better under moderate salinity level by enhancing the antioxidant activity and proline content as compared to non-AM plants.

Inorganic Salt Interference on CO2+ in Aerodyne AMS and ACSM Organic Aerosol Composition Studies.

Science.gov (United States)

Pieber, Simone M; El Haddad, Imad; Slowik, Jay G; Canagaratna, Manjula R; Jayne, John T; Platt, Stephen M; Bozzetti, Carlo; Daellenbach, Kaspar R; Fröhlich, Roman; Vlachou, Athanasia; Klein, Felix; Dommen, Josef; Miljevic, Branka; Jiménez, José L; Worsnop, Douglas R; Baltensperger, Urs; Prévôt, André S H

2016-10-04

Aerodyne aerosol mass spectrometer (AMS) and Aerodyne aerosol chemical speciation monitor (ACSM) mass spectra are widely used to quantify organic aerosol (OA) elemental composition, oxidation state, and major environmental sources. The OA CO 2 + fragment is among the most important measurements for such analyses. Here, we show that a non-OA CO 2 + signal can arise from reactions on the particle vaporizer, ion chamber, or both, induced by thermal decomposition products of inorganic salts. In our tests (eight instruments, n = 29), ammonium nitrate (NH 4 NO 3 ) causes a median CO 2 + interference signal of +3.4% relative to nitrate. This interference is highly variable between instruments and with measurement history (percentiles P 10-90 = +0.4 to +10.2%). Other semi-refractory nitrate salts showed 2-10 times enhanced interference compared to that of NH 4 NO 3 , while the ammonium sulfate ((NH 4 ) 2 SO 4 ) induced interference was 3-10 times lower. Propagation of the CO 2 + interference to other ions during standard AMS and ACSM data analysis affects the calculated OA mass, mass spectra, molecular oxygen-to-carbon ratio (O/C), and f 44 . The resulting bias may be trivial for most ambient data sets but can be significant for aerosol with higher inorganic fractions (>50%), e.g., for low ambient temperatures, or laboratory experiments. The large variation between instruments makes it imperative to regularly quantify this effect on individual AMS and ACSM systems.

Synthesis of zirconia sol stabilized by trivalent cations (yttrium and neodymium or americium): a precursor for Am-bearing cubic stabilized zirconia.

Science.gov (United States)

Lemonnier, Stephane; Grandjean, Stephane; Robisson, Anne-Charlotte; Jolivet, Jean-Pierre

2010-03-07

Recent concepts for nuclear fuel and targets for transmuting long-lived radionuclides (minor actinides) and for the development of innovative Gen-IV nuclear fuel cycles imply fabricating host phases for actinide or mixed actinide compounds. Cubic stabilized zirconia (Zr, Y, Am)O(2-x) is one of the mixed phases tested in transmutation experiments. Wet chemical routes as an alternative to the powder metallurgy are being investigated to obtain the required phases while minimizing the handling of contaminating radioactive powder. Hydrolysis of zirconium, neodymium (a typical surrogate for americium) and yttrium in aqueous media in the presence of acetylacetone was firstly investigated. Progressive hydrolysis of zirconium acetylacetonate and sorption of trivalent cations and acacH on the zirconia particles led to a stable dispersion of nanoparticles (5-7 nm) in the 6-7 pH range. This sol gels with time or with temperature. The application to americium-containing solutions was then successfully tested: a stable sol was synthesized, characterized and used to prepare cubic stabilized zirconia (Zr, Y, Am)O(2-x).

The endocannabinoid transport inhibitor AM404 differentially modulates recognition memory in rats depending on environmental aversiveness

Directory of Open Access Journals (Sweden)

Patrizia eCampolongo

2012-03-01

Full Text Available Cannabinoid compounds may influence both emotional and cognitive processes depending on the level of environmental aversiveness at the time of drug administration. However, the mechanisms responsible for these responses remain to be elucidated. The present experiments investigated the effects induced by the endocannabinoid transport inhibitor AM404 (0.5-5 mg/kg, i.p. on bothemotional and cognitive performances of rats tested in a Spatial Open Field task and subjected to different experimental settings, named High Arousal and Low Arousal conditions. The two different experimental conditions influenced emotional reactivity independently of drug administration. Indeed, vehicle-treated rats exposed to the Low Arousal condition spent more time in the centre of the arena than vehicle-treated rats exposed to the High Arousal context. Conversely, the different arousal conditions did not affect the cognitive performances of vehicle-treated animals such as the capability to discriminate a spatial displacement of the objects or an object substitution.AM404 administration did not alter the locomotor activity of the animals exposed to both environmental conditions. Interestingly, AM404 administration increased the emotional reactivity of rats exposed to the High Arousal condition but did not influence emotionality of rats exposed to the Low Arousal condition. Moreover, AM404 administration influenced the cognitive parameters depending on the level of emotional arousal: it impaired the capability of rats exposed to the High Arousal condition to recognize a novel object while it did not induce any impairing effect in rats exposed to the Low Arousal condition.These findings suggest that drugs which enhance the endocannabinoid signalling induce different effects on recognition memory performance depending on the level of emotional arousal induced by the environmental conditions.

Testing Preference Axioms in Discrete Choice experiments

DEFF Research Database (Denmark)

Hougaard, Jens Leth; Østerdal, Lars Peter; Tjur, Tue

Recent studies have tested the preference axioms of completeness and transitivity, and have detected other preference phenomena such as unstability, learning- and tiredness effects, ordering effects and dominance, in stated preference discrete choice experiments. However, it has not been explicitly...... of the preference axioms and other preference phenomena in the context of stated preference discrete choice experiments, and examine whether or how these can be subject to meaningful (statistical) tests...

[Reduction of animal experiments in experimental drug testing].

Science.gov (United States)

Behrensdorf-Nicol, H; Krämer, B

2014-10-01

In order to ensure the quality of biomedical products, an experimental test for every single manufactured batch is required for many products. Especially in vaccine testing, animal experiments are traditionally used for this purpose. For example, efficacy is often determined via challenge experiments in laboratory animals. Safety tests of vaccine batches are also mostly performed using laboratory animals. However, many animal experiments have clear inherent disadvantages (low accuracy, questionable transferability to humans, unclear significance). Furthermore, for ethical reasons and animal welfare aspects animal experiments are also seen very critical by the public. Therefore, there is a strong trend towards replacing animal experiments with methods in which no animals are used ("replacement"). If a replacement is not possible, the required animal experiments should be improved in order to minimize the number of animals necessary ("reduction") and to reduce pain and suffering caused by the experiment to a minimum ("refinement"). This "3R concept" is meanwhile firmly established in legislature. In recent years many mandatory animal experiments have been replaced by alternative in vitro methods or improved according to the 3R principles; numerous alternative methods are currently under development. Nevertheless, the process from the development of a new method to its legal implementation takes a long time. Therefore, supplementary regulatory measures to facilitate validation and acceptance of new alternative methods could contribute to a faster and more consequent implementation of the 3R concept in the testing of biomedical products.

Adsorption behavior of Am(III) on granite

International Nuclear Information System (INIS)

Zhang Yingjie; Feng Xiaogui; Liang Junfu; Chen Jing; Su Rui; Wang Ju; Liu Chunli

2009-01-01

The adsorption behavior of Am(III) on granite (sampled from drilling well BS01 at Beishan (BS) area--a potential candidate site for China's high-level radioactive waste repository, the granite sample's depth about 300 m) was studied in BS03 well groundwater by a batch technique at (25±1) degree C. The influences of pH, sulphate ion, total carbonate ion, humic acid, and concentration of the Am(III) on the adsorption behavior were also studied, and the possible adsorption mechanism was discussed. Experimental results show that the adsorption distribution rate of Am(III) on granite increases with increasing pH of aqueous phase. The chemical composition of the groundwater is the main factor which influences the species of Am(III) and adsorption behavior. The adsorption mechanism of Am(III) on granite is surface complexation. The adsorption isotherm of Am(III) on granite can be described by Freundlich's equation. (authors)

Biosorption of 241Am by Candida sp

International Nuclear Information System (INIS)

Luo Shunzhong; Zhang Taiming; Liu Ning; Yang Yuanyou; Jin Jiannan; Hua Xinfeng

2003-01-01

The biosorption of radionuclide 241 Am from solutions by Candida sp., and the influences of experimental conditions on the adsorption were studied. The results showed that the adsorption equilibrium was achieved within 4h and the optimum pH=2. No significant differences on 241 Am biosorption were observed at 10-45 degree C, or challenged with Au 3+ or Ag + , even 1500 times or 4500 times over 241 Am, respectively. The adsorption rate could reach 97.8% by dry Candida sp. of 0.82 g/L in 241 Am solutions (pH=2) of 5.6-111 MBq/L (44.04-873.0 μg/L) (C 0 ), with maximum adsorption capacity (W) of 63.5 MBq/g (501.8 μg/g), implying that the removal of 241 Am by Candida sp. from solutions was feasible. The relationship between activities (C 0 ) and adsorption capacities (W) of 241 Am indicated that the biosorption process could be described by Langmuir adsorption isotherm

Effect of assembled time on the corrosion behaviors of SAMs film on the AM60B alloy and its assembled mechanism

Energy Technology Data Exchange (ETDEWEB)

Liu, Xianbin, E-mail: xbliu@imr.ac.cn; Shan, Dayong; Song, Yingwei; Han, En-hou

2015-01-15

The influence of assembled time on the corrosion behaviors of SAMs film on the AM60B alloy and its assembled mechanism have been investigated by electrochemical measurements, scanning electron microscopy (SEM) observation and X-ray photoelectron spectroscopy (XPS) analysis. The self-assembled experiment on the AM60B magnesium alloy indicates that the corrosion susceptibility decreases with increasing assembled time until 24 h on cast AM60B alloy and then increases with increase of the assembled time proved by EIS measurement and potentiodynamic curves. The self-assembled experiments on pure magnesium and various heat treated cast AM60B magnesium alloy illuminate that the dissolved aluminum in magnesium solid solution is the key factor for assembled efficiency and is hard to self-assemble on the pure magnesium without aluminum. The corrosion resistance of self-assembled film on AM60B magnesium alloy is monotonically increasing with the dissolved aluminum. The results of XPS analysis reveal the assembled mechanism on AM60B and corroborate the function of Al element. - Highlights: • It is hard to self-assemble on the pure magnesium. • 24 h assembled film has the low corrosion susceptibility by EIS and polarization. • The corrosion susceptibility of SAMs film lie on the Al atom state in AM60B. • The corrosion susceptibility of SAMs film is decreasing with the dissolved Al.

Effect of assembled time on the corrosion behaviors of SAMs film on the AM60B alloy and its assembled mechanism

International Nuclear Information System (INIS)

Liu, Xianbin; Shan, Dayong; Song, Yingwei; Han, En-hou

2015-01-01

The influence of assembled time on the corrosion behaviors of SAMs film on the AM60B alloy and its assembled mechanism have been investigated by electrochemical measurements, scanning electron microscopy (SEM) observation and X-ray photoelectron spectroscopy (XPS) analysis. The self-assembled experiment on the AM60B magnesium alloy indicates that the corrosion susceptibility decreases with increasing assembled time until 24 h on cast AM60B alloy and then increases with increase of the assembled time proved by EIS measurement and potentiodynamic curves. The self-assembled experiments on pure magnesium and various heat treated cast AM60B magnesium alloy illuminate that the dissolved aluminum in magnesium solid solution is the key factor for assembled efficiency and is hard to self-assemble on the pure magnesium without aluminum. The corrosion resistance of self-assembled film on AM60B magnesium alloy is monotonically increasing with the dissolved aluminum. The results of XPS analysis reveal the assembled mechanism on AM60B and corroborate the function of Al element. - Highlights: • It is hard to self-assemble on the pure magnesium. • 24 h assembled film has the low corrosion susceptibility by EIS and polarization. • The corrosion susceptibility of SAMs film lie on the Al atom state in AM60B. • The corrosion susceptibility of SAMs film is decreasing with the dissolved Al

Simulating Large Area, High Intensity AM0 Illumination on Earth- Representative Testing at Elevated Temperatures for the BepiColombo and SolO Missions

Science.gov (United States)

Oberhuttinger, C.; Quabis, D.; Zimmermann, C. G.

2014-08-01

During both the BepiColombo and the Solar Orbiter (SolO) mission, severe environmental conditions with sun intensities up to 10.6 solar constants (SCs) resp. 12.8 SCs will be encountered. Therefore, a special cell design was developed which can withstand these environmental loads. To verify the solar cells under representative conditions, a set of specific tests is conducted. The key qualification test for these high intensity, high temperature (HIHT) missions is a combined test, which exposes a large number of cells simultaneously to the complete AM0 spectrum at the required irradiance and temperature. Such a test was set up in the VTC1.5 chamber located at ESTEC. This paper provides an overview of the challenges in designing a setup capable of achieving this HIHT simulation. The solutions that were developed will be presented. Also the performance of the setup will be illustrated by actual test results.

Determination of 241Am in reindeer bone

International Nuclear Information System (INIS)

Tahtinen, P.; Hakanen, M.; Jaakkola, T.; Nikula, A.

1978-01-01

The purpose of this work was to develop a procedure to separate americium from other alpha active nuclides present in reindeer bone samples, especially 228 Th and its daughter nuclides. The 241 Am-spectrum of a reindeer bone sample analyzed using the proposed method is given. The α-spectrum was measured one week after electrodeposition. The absence of the alpha peak of 224 Ra, the daughter nuclide of 228 Th, indicates that no 228 Th was electrodeposited onto the platinum disc. Four reindeer bone samples were analyzed for 241 Am using the method developed. The 241 Am/ 239 240 Pu activity ratio in reindeer bone was 0.9 :- 0.4. These results indicate that compared to plutonium, americium is accumulated in reindeer bone more heavily than in liver. All 241 Am values presented are concentrations at the time of radioassay, and no correction has been made for the ingrowth of 241 Am formed by the decay of 241 Pu during stockpilling. However, all 241 Am determinations were made 1 to 3 yrs after sample collection, and thus the corrections due to the ingrowth can be considered slight. About 60% of plutonium body burden is located in liver and 20% in skeleton. The activity ratio 241 Am/ 239 240 Pu in these animals was about 0.2 and 1.0 in liver and skeleton, respectively. This indicates that about 60% of the 241 Am body burden is located in skeleton and about 30% in liver. It can be roughly estimated that the whole-body activity of 241 Am is thus about 40% of the 239 240 Pu body burden

Improved MOX fuel calculations using new Pu-239, Am-241 and Pu-240 evaluations

International Nuclear Information System (INIS)

Noguere, G.; Bouland, O.; Bernard, D.; Leconte, P.; Blaise, P.; Peneliau, Y.; Vidal, J.F.; Saint Jean, C. de; Leal, L.; Schilleebeeckx, P.; Kopecky, S.; Lampoudis, C.

2013-01-01

Several studies based on the JEFF-3.1.1 nuclear data library show a systematic over-estimation of the critical keff for core configurations of MOX fuel assemblies. The present work investigates possible improvements of the C/E results by using new evaluations for Am-241, Pu-239 and Pu-240. The work reported in this paper demonstrates the performances of the new Am-241 evaluation based on capture and transmission data measured at the IRMM. For Pu-239, the new evaluation, established in the frame of the WPEC/SG-34, is able to explain a systematic discrepancy observed between different EOLE experiments. The combination of the Am-241 and Pu-239 evaluations demonstrates the necessity to improve the radiation width of the first resonance of Pu-240

Cosmic gamma ray detection and discovery potential with the AMS-2 spectrometer; Detection de rayons {gamma} cosmiques et potentiel de decouvertes avec le spectrometre AMS-02

Energy Technology Data Exchange (ETDEWEB)

Girard, L

2004-12-15

Yet designed to measure charged component of the cosmic rays, the foreseen Alpha Magnetic Spectrometer (AMS-02) could also release {gamma}-ray studies, in the energy range from GeV to TeV, using the tracker system, for {gamma}-rays converted in e{sup +}e{sup -} pair, and the electromagnetic calorimeter. In the first part of the thesis are described the calibrations and the performances of the engineering model of the calorimeter, obtained from the analysis of data taken during a test-beam performed at CERN in July 2002. In the second part of the thesis, the AMS-02 discovery potential for {gamma}-astrophysics is presented. While exposure maps of the {gamma}--sky are computed for one year of data taking with the {gamma}--detectors, the acceptance of the calorimeter is obtained from Monte-Carlo simulations. The AMS-02 potential is then estimated for signals from the Vela pulsar and for some supersymmetric signals from the Galactic Center. (author)

AMS-02 data confront acceleration of cosmic ray secondaries in nearby sources

DEFF Research Database (Denmark)

Mertsch, Philipp; Sarkar, Subir

2014-01-01

We revisit the model proposed earlier to account for the observed increase in the positron fraction in cosmic rays with increasing energy, in the light of new data from the Alpha Magnetic Spectrometer (AMS-02) experiment. The model accounts for the production and acceleration of secondary electrons...

AMS Days: "the results are phenomenal"

CERN Multimedia

2015-01-01

Following the conclusion of the successful AMS Days at CERN (see here), we sat down with leading minds in space science and particle physics to discuss their thoughts on the recent positron-excess results as well as the future of the AMS physics programme.   Samuel Ting, AMS spokesperson: Roberto Battiston, President of the Italian Space Agency (ASI): William H. Gerstenmaier, Human Exploration and Operations Directorate, NASA: Edward C. Stone (Caltech), Voyager 1 and 2 principal investigator:

Search for positron anisotropies in cosmic rays with AMS

Energy Technology Data Exchange (ETDEWEB)

Machate, Fabian [1. Physikalisches Institut B, RWTH Aachen University (Germany)

2016-07-01

The Alpha Magnetic Spectrometer (AMS-02) on the International Space Station has observed a significant excess of cosmic ray positrons over the background expected from secondary production at energies above 10 GeV. Nearby pulsars and annihilating dark matter particles as a primary source of electrons and positrons have been discussed as an explanation. A possible way of distinguishing between pulsar and dark matter origin is the measurement of dipole anisotropies in the positron flux or the positron to electron ratio. Any anisotropy will be reduced by diffusion in galactic magnetic fields to below the percent level. AMS-02 is the leading space-based experiment for cosmic ray detection and well suited for this search. A new analysis procedure for anisotropies using an event sample with large acceptance is presented. It relies on the ability of the Transition Radiation Detector (TRD) to separate positrons from the proton background.

Increasing Scientific Literacy at Minority Serving Institutions Nationwide through AMS Professional Development Diversity Workshops

Science.gov (United States)

Brey, J. A.; Geer, I. W.; Mills, E. W.; Nugnes, K. A.; Moses, M. N.

2011-12-01

Earth and back sets the stage for differentiating between climate, climate variability, and climate change. The AMS Climate Studies Diversity Project will follow the successful models of the Weather and Ocean Diversity Projects. Hands on examples, computer based experiments, round table discussions, lectures, and conversations with scientists in the field and other experienced professors are all important parts of previous workshops, and will be complimented by previous participants' feedback. This presentation will also focus on insight gained from the results of a self-study of the long term, successful AMS DataStreme Project, precollege teacher professional development courses. AMS is excited for this new opportunity of reaching even more MSI faculty and students. The ultimate goal of the AMS is to have a geoscience concentration at MSIs throughout the nation and to greatly increase the number of minority students entering geoscience careers, including science teaching.

Status of recent utilization of JAEA AMS MUTSU

International Nuclear Information System (INIS)

Amano, Hikaru; Kabuto, Shoji; Kinoshita, Naoki

2008-01-01

Tandetron AMS was set up at the JAEA Mutsu in 1997. This AMS has been used for the determination of 14 C/ 12 C and 129 I/ 127 I. So far, 7075 samples have been measured for the 14 C-AMS, and 1317 samples have been measured for the 129 I-AMS until the end of September 2007. This AMS has adopted the open door policy which is periodic filing of applications and judgment for use twice a year, expecting broad usage including environmental issue and estimation of radioactive wastes for the general users from the spring of 2006. Eight external assignments have adopted in the first half of 2007, eleven external assignments have adopted in the latter half of 2007 at the JAEA AMS MUTSU. (author)

A simple Bragg detector design for AMS and IBA applications

Energy Technology Data Exchange (ETDEWEB)

Müller, Arnold Milenko; Döbeli, Max; Seiler, Martin; Synal, Hans-Arno

2015-08-01

A new compact Bragg type gas ionization chamber (GIC) has been built for use as particle counter in AMS and IBA applications. The detector stands out due to its simple concept, which does not include a Frisch grid. Test experiments have been performed with ions in the mass range from He to Th and energies ranging from 30 keV to 2.5 MeV, in order to find optimal measurement conditions and to characterize the detector performance. For projectiles heavier than Al at energies below 2.5 MeV the obtained energy resolution is comparable with that of a state-of-the-art GIC with Frisch grid and clearly outperforms solid state detectors. Additionally the operation of this simplified Bragg GIC in the electron multiplication mode was investigated for the first time, which allows the detection of radiocarbon ions at energies below 50 keV with an energy resolution of the order of 10 keV.

Irradiation test of fuel containing minor actinides in the experimental fast reactor Joyo

International Nuclear Information System (INIS)

Soga, Tomonori; Sekine, Takashi; Wootan, David; Tanaka, Kosuke; Kitamura, Ryoichi; Aoyama, Takafumi

2007-01-01

The mixed oxide containing minor actinides (MA-MOX) fuel irradiation program is being conducted using the experimental fast reactor Joyo of the Japan Atomic Energy Agency to research early thermal behavior of MA-MOX fuel. Two irradiation experiments were conducted in the Joyo MK-III 3rd operational cycle. Six prepared fuel pins included MOX fuel containing 3% or 5% americium (Am-MOX), MOX fuel containing 2% americium and 2% neptunium (Np/Am-MOX), and reference MOX fuel. The first test was conducted with high linear heat rates of approximately 430 W/cm maintained during only 10 minutes in order to confirm whether or not fuel melting occurred. After 10 minutes irradiation in May 2006, the test subassembly was transferred to the hot cell facility and an Am-MOX pin and a Np/Am-MOX pin were replaced with dummy pins including neutron dosimeters. The test subassembly loaded with the remaining four fuel pins was re-irradiated in Joyo for 24-hours in August 2006 at nearly the same linear power to obtain re-distribution data on MA-MOX fuel. Linear heat rates for each pin were calculated using MCNP, accounting for both prompt and delayed heating components, and then adjusted using E/C for 10 B (n, α) reaction rates measured in the MK-III core neutron field characterization test. Post irradiation examination of these pins to confirm the fuel melting and the local concentration under irradiation of NpO 2-x or AmO 2-x in the (U, Pu)O 2-x fuel are underway. The test results are expected to reduce uncertainties on the design margin in the thermal design for MA-MOX fuel. (author)

Using "I Am Moving, I Am Learning" to Increase Quality Instruction in Head Start Classrooms

Science.gov (United States)

Allar, Ishonté; Jones, Emily; Bulger, Sean

2018-01-01

Quality teacher-child interactions are characteristic of effective classrooms resulting in benefits for all children, but may be particularly important for children from low-income families. The purpose of this study was to explore the perception of Illinois Head Start teachers related to how "I am Moving, I am Learning" (IMIL) could…

Characterizing experiments of the PPOOLEX test facility

Energy Technology Data Exchange (ETDEWEB)

Puustinen, M.; Laine, J. (Lappeenranta Univ. of Technology, Nuclear Safety Research Unit (Finland))

2008-07-15

This report summarizes the results of the characterizing test series in 2007 with the scaled down PPOOLEX facility designed and constructed at Lappeenranta University of Technology. Air and steam/air mixture was blown into the dry well compartment and from there through a DN200 blowdown pipe to the condensation pool (wet well). Altogether eight air and four steam/air mixture experiments, each consisting of several blows (tests), were carried out. The main purpose of the experiment series was to study the general behavior of the facility and the performance of basic instrumentation. Proper operation of automation, control and safety systems was also tested. The test facility is a closed stainless steel vessel divided into two compartments, dry well and wet well. The facility is equipped with high frequency measurements for capturing different aspects of the investigated phenomena. The general behavior of the PPOOLEX facility differs significantly from that of the previous POOLEX facility because of the closed two-compartment structure of the test vessel. Heat-up by several tens of degrees due to compression in both compartments was the most obvious evidence of this. Temperatures also stratified. Condensation oscillations and chugging phenomenon were encountered in those tests where the fraction of non-condensables had time to decrease significantly. A radical change from smooth condensation behavior to oscillating one occurred quite abruptly when the air fraction of the blowdown pipe flow dropped close to zero. The experiments again demonstrated the strong diminishing effect that noncondensable gases have on dynamic unsteady loadings experienced by submerged pool structures. BWR containment like behavior related to the beginning of a postulated steam line break accident was observed in the PPOOLEX test facility during the steam/air mixture experiments. The most important task of the research project, to produce experimental data for code simulation purposes, can be

Elements in biological AMS

International Nuclear Information System (INIS)

Vogel, J.S.; McAninch, J.; Freeman, S.

1996-08-01

AMS (Accelerator Mass Spectrometry) provides high detection sensitivity for isotopes whose half-lives are between 10 years and 100 million years. 14 C is the most developed of such isotopes and is used in tracing natural and anthropogenic organic compounds in the Earth's biosphere. Thirty-three elements in the main periodic table and 17 lanthanides or actinides have long lived isotopes, providing potential tracers for research in elemental biochemistry. Overlap of biologically interesting heavy elements and possible AMS tracers is discussed

The potential of coconut fibers in raw and treated forms to remove 241Am from aqueous solutions

International Nuclear Information System (INIS)

Fonseca, Heverton C.O.; Jesus, Nella N.M. de; Nobre, Vanessa B.; Potiens Junior, Ademar; Sakata, Solange K.

2013-01-01

In the Radioactive Waste Management (GRR) at the Nuclear and Energy Research Institute (IPEN/CNEN-SP) vegetal biomass has been studied as adsorbent to remove radioisotopes from radioactive liquid wastes as part of the radioactive waste treatment program. In this work coconuts fiber was evaluate as biosorbent to remove 241 Am from aqueous solutions and many different parameters were studied such as particle size (35 and 80 mesh) and contact time (between 5 and 60 minutes). In order to evaluate if the treated biomass could remove more 241 Am the experiments were also performed using raw biomass and treated with H 2 O 2 in basic conditions. When the experiment was carried out using raw coconuts fiber with 80 mesh, neutral conditions after 5 minutes of contact time 99% of the radionuclide was removed from the aqueous solution. This result shows the potential of this biomass to remove 241 Am from radioactive liquid wastes. (author)

The new 6 MV multi-nuclide AMS facility at the University of Tsukuba

Energy Technology Data Exchange (ETDEWEB)

Sasa, Kimikazu, E-mail: ksasa@tac.tsukuba.ac.jp; Takahashi, Tsutomu; Matsumura, Masumi; Matsunaka, Tetsuya; Satou, Yukihiko; Izumi, Daiki; Sueki, Keisuke

2015-10-15

The former accelerator mass spectrometry (AMS) system installed on the 12UD Pelletron tandem accelerator at the University of Tsukuba was completely destroyed by the Great East Japan Earthquake on 11 March 2011. A replacement has been designed and constructed at the university as part of the post-quake reconstruction project. It consists of a 6 MV Pelletron tandem accelerator, two multiple cathode AMS ion sources (MC-SNICSs), and a rare-particle detection system. The 6 MV Pelletron tandem accelerator will be applied not only to AMS, but also to areas such as nanotechnology, ion beam analysis, heavy ion irradiation, and nuclear physics. The rare-particle detection system will be capable of measuring environmental levels of long-lived radioisotopes of {sup 10}Be, {sup 14}C, {sup 26}Al, {sup 36}Cl, {sup 41}Ca, and {sup 129}I. It is also expected to measure other radioisotopes such as {sup 32}Si and {sup 90}Sr. The 6 MV Pelletron tandem accelerator was installed in the spring of 2014 at the University of Tsukuba. Routine beam delivery and AMS experiments will start in 2015.

The new 6 MV multi-nuclide AMS facility at the University of Tsukuba

International Nuclear Information System (INIS)

Sasa, Kimikazu; Takahashi, Tsutomu; Matsumura, Masumi; Matsunaka, Tetsuya; Satou, Yukihiko; Izumi, Daiki; Sueki, Keisuke

2015-01-01

The former accelerator mass spectrometry (AMS) system installed on the 12UD Pelletron tandem accelerator at the University of Tsukuba was completely destroyed by the Great East Japan Earthquake on 11 March 2011. A replacement has been designed and constructed at the university as part of the post-quake reconstruction project. It consists of a 6 MV Pelletron tandem accelerator, two multiple cathode AMS ion sources (MC-SNICSs), and a rare-particle detection system. The 6 MV Pelletron tandem accelerator will be applied not only to AMS, but also to areas such as nanotechnology, ion beam analysis, heavy ion irradiation, and nuclear physics. The rare-particle detection system will be capable of measuring environmental levels of long-lived radioisotopes of "1"0Be, "1"4C, "2"6Al, "3"6Cl, "4"1Ca, and "1"2"9I. It is also expected to measure other radioisotopes such as "3"2Si and "9"0Sr. The 6 MV Pelletron tandem accelerator was installed in the spring of 2014 at the University of Tsukuba. Routine beam delivery and AMS experiments will start in 2015.

21 CFR 822.24 - What are my responsibilities once I am notified that I am required to conduct postmarket...

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false What are my responsibilities once I am notified that I am required to conduct postmarket surveillance? 822.24 Section 822.24 Food and Drugs FOOD AND... SURVEILLANCE Responsibilities of Manufacturers § 822.24 What are my responsibilities once I am notified that I...

Bioanalysis works in the IAA AMS facility: Comparison of AMS analytical method with LSC method in human mass balance study

International Nuclear Information System (INIS)

Miyaoka, Teiji; Isono, Yoshimi; Setani, Kaoru; Sakai, Kumiko; Yamada, Ichimaro; Sato, Yoshiaki; Gunji, Shinobu; Matsui, Takao

2007-01-01

Institute of Accelerator Analysis Ltd. (IAA) is the first Contract Research Organization in Japan providing Accelerator Mass Spectrometry (AMS) analysis services for carbon dating and bioanalysis works. The 3 MV AMS machines are maintained by validated analysis methods using multiple control compounds. It is confirmed that these AMS systems have reliabilities and sensitivities enough for each objective. The graphitization of samples for bioanalysis is prepared by our own purification lines including the measurement of total carbon content in the sample automatically. In this paper, we present the use of AMS analysis in human mass balance and metabolism profiling studies with IAA 3 MV AMS, comparing results obtained from the same samples with liquid scintillation counting (LSC). Human samples such as plasma, urine and feces were obtained from four healthy volunteers orally administered a 14 C-labeled drug Y-700, a novel xanthine oxidase inhibitor, of which radioactivity was about 3 MBq (85 μCi). For AMS measurement, these samples were diluted 100-10,000-fold with pure-water or blank samples. The results indicated that AMS method had a good correlation with LSC method (e.g. plasma: r = 0.998, urine: r = 0.997, feces: r = 0.997), and that the drug recovery in the excreta exceeded 92%. The metabolite profiles of plasma, urine and feces obtained with HPLC-AMS corresponded to radio-HPLC results measured at much higher radioactivity level. These results revealed that AMS analysis at IAA is useful to measure 14 C-concentration in bioanalysis studies at very low radioactivity level

Additive Manufacturing (AM) Activities and Non-Destructive Evaluation (NDE) at GSFC

Science.gov (United States)

Jones, Justin S.

2017-01-01

NASA personnel will be meeting with a delegation from the Japan Aerospace Exploration Agency (JAXA) Office of Safety and Mission Assurance (OSMA) at Langley Research Center on 2217 through 3217. The purpose of the meeting is a technical interchange between NASA and JAXA to discuss Non-Destructive Evaluation (NDE) of Additive Manufacturing (AM) parts and the HALT process (relates to accelerated life testing). The visitors will be a small group of Japanese citizens. Goddard Space Flight Center (GSFC) has been asked to participate in the meeting, either in person or via teleconference. This presentation covers NDE efforts at GSFC and provides a cursory overview of AM and lab capabilities.

Testing neoclassical competitive market theory in the field.

Science.gov (United States)

List, John A

2002-11-26

This study presents results from a pilot field experiment that tests predictions of competitive market theory. A major advantage of this particular field experimental design is that my laboratory is the marketplace: subjects are engaged in buying, selling, and trading activities whether I run an exchange experiment or am a passive observer. In this sense, I am gathering data in a natural environment while still maintaining the necessary control to execute a clean comparison between treatments. The main results of the study fall into two categories. First, the competitive model predicts reasonably well in some market treatments: the expected price and quantity levels are approximated in many market rounds. Second, the data suggest that market composition is important: buyer and seller experience levels impact not only the distribution of rents but also the overall level of rents captured. An unexpected result in this regard is that average market efficiency is lowest in markets that match experienced buyers and experienced sellers and highest when experienced buyers engage in bargaining with inexperienced sellers. Together, these results suggest that both market experience and market composition play an important role in the equilibrium discovery process.

Construction and qualification of the Power Supply system of the AMS-02 Tracker detector

International Nuclear Information System (INIS)

Menichelli, M.; Accardo, L.; Ambrosi, G.; Battiston, R.; Bizzarri, M.; Blasko, S.; Cosson, D.; Fiori, E.M.; Maris, O.; Papi, A.; Scolieri, G.

2007-01-01

The AMS-02 Tracker power supply system, described in this paper, has been designed optimizing noise performances, modularity and efficiency. The power is distributed starting from a 28V line coming from the power distribution system is converted into the needed voltages by means of DC-DC converters, and for bias supply and front-end voltages is post-regulated by means of linear regulators. Components Off The Shelf (COTS) have been extensively used in the construction of this power supply, however various radiation test campaigns have been performed in order to verify the reliability of these components. The power supply architecture developed for the tracker detector has been used as a guideline for the development of the power supplies for the other detectors in the experiment

How AMS dating changed my life

International Nuclear Information System (INIS)

Spriggs, M.

2001-01-01

Accelerator mass spectrometry (AMS) radiocarbon dating was developed in the late 1970s. Remembering back to a time before AMS dating was available to archaeologists is a bit like trying to remember how we ever survived without desktop computers, email or automatic teller machines. My own particular interest in AMS dating was an inevitable offshoot from my long-established interest in chronometric hygiene, or 'getting the dates right'. In this paper I attempt to illustrate that accurate dating matters, by discussing some examples of AMS dating projects with which I have been involved over the last six years or so. In relation to these projects, AMS has given us the ability to date sites which we could not before. It has enabled us to provide more detailed stratigraphies when datable materials are rare. It has allowed us to date materials we could not date before, such as rock art pigments. It has been able to provide indications of the degree of site disturbance in the absence of other obvious forms of evidence. And it has allowed us to assess claims for the antiquity of particular material cultural types and faunal introductions. (author). 41 refs

The transient evolution of AM mode locking a TEA CO2laser

NARCIS (Netherlands)

van Goor, F.A.; Bonnie, Ronald J.M.; Witteman, W.J.

1985-01-01

The evolution of the pulse in an AM mode-locked TEA CO2laser has been investigated. The experiments have been performed by injecting the mode-locked pulses in a high-pressure slave oscillator at various time intervals after the initiation of the mode-lock process. This technique allows the

Operating experiences since rise-to-power test in high temperature engineering test reactor (HTTR)

International Nuclear Information System (INIS)

Tochio, Daisuke; Watanabe, Shuji; Motegi, Toshihiro; Kawano, Shuichi; Kameyama, Yasuhiko; Sekita, Kenji; Kawasaki, Kozo

2007-03-01

The rise-to-power test of the High Temperature Engineering Test Reactor (HTTR) was actually started in April 2000. The rated thermal power of 30MW and the rated reactor outlet coolant temperature of 850degC were achieved in the middle of Dec. 2001. After that, the reactor thermal power of 30MW and the reactor outlet coolant temperature of 950degC were achieved in the final rise-to-power test in April 2004. After receiving the operation licensing at 850degC, the safety demonstration tests have conducted to demonstrate inherent safety features of the HTGRs as well as to obtain the core and plant transient data for validation of safety analysis codes and for establishment of safety design and evaluation technologies. This paper summarizes the HTTR operating experiences for six years from start of the rise-to-power test that are categorized into (1) Operating experiences related to advanced gas-cooled reactor design, (2) Operating experiences for improvement of the performance, (3) Operating experiences due to fail of system and components. (author)

Production of monodisperse respirable aerosols of 241AmO2 and evaluation of in vitro dissolution

International Nuclear Information System (INIS)

Boyd, H.A.; Raabe, O.G.; Peterson, P.K.

1974-01-01

A method is described for production of monodisperse (sigma//sub g/ less than 1.2) particles of 241 AmO 2 for use in inhalation experiments with dogs and rodents. The effects of physical and chemical factors on the production of polydisperse aerosols of 241 AmO 2 were studied and evaluated. The best aerosol was achieved when a suspension of americium hydroxide with 2.5 mg Am/ml at pH = 7.3 was aerosolized and passed through two heating columns in succession, the first at 300 0 C and the second at 1050 0 C. The particles were roughly spherical and had densities near 8 gm/cm 3 ; the aerosol AMAD and sigma/sub g/ were about 1.5 μm and 1.7, respectively. Monodisperse particles were separated and collected with the Lovelace Aerosol Particle Separator (LAPS) and subsequently suspended in deionized water with pH adjusted to 10.2 with NH 3 for nebulization to produce monodisperse aerosols for inhalation exposures. Particles collected on filters during inhalation experiments were used for evaluation of in vitro dissolution rates with two systems and various forms of a lung fluid simulant. The important role of phosphate ions in such dissolution systems was demonstrated, suggesting the potential for the equally important role of free phosphate in retarding dissolution of AmO 2 particles in the lung. (U.S.)

Study of the properties of the Am-O system in view of the transmutation of Am 241 in fast reactors

International Nuclear Information System (INIS)

Casalta, S.

1996-04-01

To reduce the long term toxicity of Am 241 it was considered to transmute this isotope in fast reactor. The first part of this thesis is an introduction at this problem. In the second part we give the experimental techniques used for the realisation of an AmO 2 -MgO target (powder metallurgy under inert, oxidizing or reducing atmosphere). The properties of the Am-O system has been analyzed by X diffraction, thermodynamic and ceramography, in the Am 2 O 3 -AmO 2 field. In the third part we study the external exposure risk created by the manufacturing of this target and in the last part the behavior of this target in a fast reactor. 66 refs., 28 figs., 25 tabs., 1 append

AMS-02 fits dark matter

Science.gov (United States)

Balázs, Csaba; Li, Tong

2016-05-01

In this work we perform a comprehensive statistical analysis of the AMS-02 electron, positron fluxes and the antiproton-to-proton ratio in the context of a simplified dark matter model. We include known, standard astrophysical sources and a dark matter component in the cosmic ray injection spectra. To predict the AMS-02 observables we use propagation parameters extracted from observed fluxes of heavier nuclei and the low energy part of the AMS-02 data. We assume that the dark matter particle is a Majorana fermion coupling to third generation fermions via a spin-0 mediator, and annihilating to multiple channels at once. The simultaneous presence of various annihilation channels provides the dark matter model with additional flexibility, and this enables us to simultaneously fit all cosmic ray spectra using a simple particle physics model and coherent astrophysical assumptions. Our results indicate that AMS-02 observations are not only consistent with the dark matter hypothesis within the uncertainties, but adding a dark matter contribution improves the fit to the data. Assuming, however, that dark matter is solely responsible for this improvement of the fit, it is difficult to evade the latest CMB limits in this model.

AMS-02 fits dark matter

Energy Technology Data Exchange (ETDEWEB)

Balázs, Csaba; Li, Tong [ARC Centre of Excellence for Particle Physics at the Tera-scale,School of Physics and Astronomy, Monash University, Melbourne, Victoria 3800 (Australia)

2016-05-05

In this work we perform a comprehensive statistical analysis of the AMS-02 electron, positron fluxes and the antiproton-to-proton ratio in the context of a simplified dark matter model. We include known, standard astrophysical sources and a dark matter component in the cosmic ray injection spectra. To predict the AMS-02 observables we use propagation parameters extracted from observed fluxes of heavier nuclei and the low energy part of the AMS-02 data. We assume that the dark matter particle is a Majorana fermion coupling to third generation fermions via a spin-0 mediator, and annihilating to multiple channels at once. The simultaneous presence of various annihilation channels provides the dark matter model with additional flexibility, and this enables us to simultaneously fit all cosmic ray spectra using a simple particle physics model and coherent astrophysical assumptions. Our results indicate that AMS-02 observations are not only consistent with the dark matter hypothesis within the uncertainties, but adding a dark matter contribution improves the fit to the data. Assuming, however, that dark matter is solely responsible for this improvement of the fit, it is difficult to evade the latest CMB limits in this model.

América Latina

Directory of Open Access Journals (Sweden)

Marcos Olalla

2007-01-01

Full Text Available Este trabajo analiza el sentido intelectualista de la producción literaria modernista de Latinoamérica. Dicho enfoque es revisado en la obra del escritor argentino Manuel Ugarte (1875-1951 El porvenir de América Latina (1910. Nuestra lectura ofrece algunas líneas para la discriminación de las diversas fuentes ideológicas del intelectualismo en el “americanismo literario”. Consideramos en tal sentido la perspectiva historicista con la que Ugarte describe la composición social de América Latina.

Status report on sample preparation facilities for 14C analysis at the new CologneAMS center

International Nuclear Information System (INIS)

Rethemeyer, J.; Fülöp, R.-H.; Höfle, S.; Wacker, L.; Heinze, S.; Hajdas, I.; Patt, U.; König, S.; Stapper, B.; Dewald, A.

2013-01-01

The new AMS facility at University of Cologne (CologneAMS), Germany, was established in 2010 with the delivery of the HVE 6 MV Tandetron AMS, which will be used for 14 C, 26 Al, 36 Cl, 41 Ca, 129 I, 239 U and 244 Pu analyses. Parallel to the AMS installation the radiocarbon group has started to set up and test sample preparation methods and instruments for different materials. We present first results of reference and standard materials that have been processed and graphitized in our lab and measured at the ETH and CologneAMS facilities. The graphitization blank and its influence on small samples sizes processed with an automated graphitization system have been determined. Work on isolation of individual organic compounds with a preparative gas chromatography system has been started. The focus of our future work will be on reducing process blank levels and sample sizes as well as on the application of compound-specific radiocarbon analyses in (paleo-) environmental research.

DReAM: Demand Response Architecture for Multi-level District Heating and Cooling Networks

Energy Technology Data Exchange (ETDEWEB)

Bhattacharya, Saptarshi; Chandan, Vikas; Arya, Vijay; Kar, Koushik

2017-05-19

In this paper, we exploit the inherent hierarchy of heat exchangers in District Heating and Cooling (DHC) networks and propose DReAM, a novel Demand Response (DR) architecture for Multi-level DHC networks. DReAM serves to economize system operation while still respecting comfort requirements of individual consumers. Contrary to many present day DR schemes that work on a consumer level granularity, DReAM works at a level of hierarchy above buildings, i.e. substations that supply heat to a group of buildings. This improves the overall DR scalability and reduce the computational complexity. In the first step of the proposed approach, mathematical models of individual substations and their downstream networks are abstracted into appropriately constructed low-complexity structural forms. In the second step, this abstracted information is employed by the utility to perform DR optimization that determines the optimal heat inflow to individual substations rather than buildings, in order to achieve the targeted objectives across the network. We validate the proposed DReAM framework through experimental results under different scenarios on a test network.

AMS, a particle spectrometer in space

International Nuclear Information System (INIS)

Buenerd, M.; Ohlsson-Malek, F.; Ren, Z.L.; Santos, D.; Thuillier, T.

1997-01-01

The Alpha Magnetic Spectrometer (AMS) is a detector designed for extraterrestrial study of anti-matter, matter and dark matter. A precursor flight and on the STS-91 flight of the shuttle is planned to take place on May 1998. AMS will be installed on the International Space Station in January 2002 where it will be operated next, for three to five years. The contributions of the ISN to the project on the shuttle (aerogel threshold Cherenkov counter) as well as the steps to build a RICH detector for AMS on the ISSA are explained here below. (authors)

The potential of coconut fibers in raw and treated forms to remove {sup 241}Am from aqueous solutions

Energy Technology Data Exchange (ETDEWEB)

Fonseca, Heverton C.O.; Jesus, Nella N.M. de; Nobre, Vanessa B.; Potiens Junior, Ademar; Sakata, Solange K., E-mail: sksakata@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

In the Radioactive Waste Management (GRR) at the Nuclear and Energy Research Institute (IPEN/CNEN-SP) vegetal biomass has been studied as adsorbent to remove radioisotopes from radioactive liquid wastes as part of the radioactive waste treatment program. In this work coconuts fiber was evaluate as biosorbent to remove {sup 241}Am from aqueous solutions and many different parameters were studied such as particle size (35 and 80 mesh) and contact time (between 5 and 60 minutes). In order to evaluate if the treated biomass could remove more {sup 241}Am the experiments were also performed using raw biomass and treated with H{sub 2}O{sub 2} in basic conditions. When the experiment was carried out using raw coconuts fiber with 80 mesh, neutral conditions after 5 minutes of contact time 99% of the radionuclide was removed from the aqueous solution. This result shows the potential of this biomass to remove {sup 241}Am from radioactive liquid wastes. (author)

Laboratory column experiments for radionuclide adsorption studies of the Culebra dolomite member of the Rustler Formation

International Nuclear Information System (INIS)

Lucero, D.A.; Heath, C.E.; Brown, G.O.

1998-04-01

Radionuclide transport experiments were carried out using intact cores obtained from the Culebra member of the Rustler Formation inside the Waste Isolation Pilot Plant, Air Intake Shaft. Twenty-seven separate tests are reported here and include experiments with 3 H, 22 Na, 241 Am, 239 Np, 228 Th, 232 U and 241 Pu, and two brine types, AIS and ERDA 6. The 3 H was bound as water and provides a measure of advection, dispersion, and water self-diffusion. The other tracers were injected as dissolved ions at concentrations below solubility limits, except for americium. The objective of the intact rock column flow experiments is to demonstrate and quantify transport retardation coefficients, (R) for the actinides Pu, Am, U, Th and Np, in intact core samples of the Culebra Dolomite. The measured R values are used to estimate partition coefficients, (kd) for the solute species. Those kd values may be compared to values obtained from empirical and mechanistic adsorption batch experiments, to provide predictions of actinide retardation in the Culebra. Three parameters that may influence actinide R values were varied in the experiments; core, brine and flow rate. Testing five separate core samples from four different core borings provided an indication of sample variability. While most testing was performed with Culebra brine, limited tests were carried out with a Salado brine to evaluate the effect of intrusion of those lower waters. Varying flow rate provided an indication of rate dependent solute interactions such as sorption kinetics

AMS: From the ISS to CERN

CERN Multimedia

Jordan Juras

2011-01-01

The week of 16 May 2011 saw the successful launch and installation of the Alpha Magnetic Spectrometer aboard the International Space Station. Only 4 minutes after the installation had been completed, cosmic event data started to be recorded and began its long journey from low Earth orbit to the newly constructed Payload Operations and Control Centre located on CERN's Prévessin site.    The AMS Control Room in the newly constructed Building 946 in CERN’s Prévessin site. Unlike the detectors around the LHC ring, the Alpha Magnetic Spectrometer (AMS) does not have the luxury of a physical connection to data-processing infrastructure. Instead, cosmic events and data on AMS itself must undergo a lengthy journey before they arrive at the Payload and Operations on the Control Centre (POCC - building 946 Prévessin site) of the AMS collaboration. A joint effort between NASA and CERN makes this transmission possible. “The Space Stat...

ATHLET validation using accident management experiments

Energy Technology Data Exchange (ETDEWEB)

Teschendorff, V.; Glaeser, H.; Steinhoff, F. [Gasellschaft fuer Anlagen - und Reaktorsicherheit (GSR) mbH, Garching (Germany)

1995-09-01

The computer code ATHLET is being developed as an advanced best-estimate code for the simulation of leaks and transients in PWRs and BWRs including beyond design basis accidents. The code has features that are of special interest for applications to small leaks and transients with accident management, e.g. initialisation by a steady-state calculation, full-range drift-flux model, and dynamic mixture level tracking. The General Control Simulation Module of ATHLET is a flexible tool for the simulation of the balance-of-plant and control systems including the various operator actions in the course of accident sequences with AM measures. The systematic validation of ATHLET is based on a well balanced set of integral and separate effect tests derived from the CSNI proposal emphasising, however, the German combined ECC injection system which was investigated in the UPTF, PKL and LOBI test facilities. PKL-III test B 2.1 simulates a cool-down procedure during an emergency power case with three steam generators isolated. Natural circulation under these conditions was investigated in detail in a pressure range of 4 to 2 MPa. The transient was calculated over 22000 s with complicated boundary conditions including manual control actions. The calculations demonstrations the capability to model the following processes successfully: (1) variation of the natural circulation caused by steam generator isolation, (2) vapour formation in the U-tubes of the isolated steam generators, (3) break-down of circulation in the loop containing the isolated steam generator following controlled cool-down of the secondary side, (4) accumulation of vapour in the pressure vessel dome. One conclusion with respect to the suitability of experiments simulating AM procedures for code validation purposes is that complete documentation of control actions during the experiment must be available. Special attention should be given to the documentation of operator actions in the course of the experiment.

Thermoresponsive behaviour of AM{sub 2}O{sub 8} materials

Energy Technology Data Exchange (ETDEWEB)

Allen, Simon

2003-07-01

This thesis investigates the synthesis and structural characterisation of AM{sub 2}O{sub 8} phases, many of which show negative thermal expansion (NTE); relevant literature is reviewed in Chapter One. Chapter Two describes the synthesis, structure solution, and mechanistic role of a new family of low-temperature (LT) orthorhombic AM{sub 2}O{sub 8} polymorphs (A{sup IV} = Zr, Hf; M{sup VI} = Mo, W). These materials are key intermediates in the preparation of cubic AM{sub 2}O{sub 8} phases from AM{sub 2}O{sub 7}(OH){sub 2}(H{sub 2}O){sub 2}. The structure of LT-AM{sub 2}O{sub 8} has been elucidated by combined laboratory X-ray and neutron powder diffraction. Variable temperature X-ray diffraction (VTXRD) studies have shown LT-AMo{sub 2}O{sub 8} phases exhibit anisotropic NTE. LT-ZrMo{sub 2}O{sub 8} has been shown to undergo spontaneous rehydration, allowing preparation of ZrMo{sub 2}O{sub 7}(OD){sub 2}(D{sub 2}O){sub 2} and assignment of D{sub 2}O/OD positions within the structure by neutron diffraction. Using this result, a reversible topotactic dehydration pathway from AM{sub 2}O{sub 7}(OH){sub 2}(H{sub 2}O){sub 2} to LT-AM{sub 2}O{sub 8} is proposed. Chapter Three investigates the order-disorder phase transition with concurrent oxygen mobility in cubic AM{sub 2}O{sub 8} materials; studies include comprehensive VT neutron diffraction of cubic ZrMo{sub 2}O{sub 8} to reveal a static to dynamic transition at 215 K, and novel quench-anneal/quench-warm variable temperature/time diffraction experiments on ZrWMoO{sub 8} which lead to an activation energy of 40 kJmol{sup -1} for oxygen migration. In Chapter Four {sup 17}O-labelled cubic ZrW{sub 2}O{sub 8} has been prepared to understand the oxygen migration process by VT MAS NMR. In situ hydrothermal studies of cubic ZrMo{sub 2}O{sub 8} using synchrotron radiation have shown direct hydration to ZrMo{sub 2}O{sub 7}(OH){sub 2}(H{sub 2}O){sub 2}. In Chapter Five VTXRD of trigonal {alpha}-AMo{sub 2}O{sub 8} phases reveals a

Comparison Study on Additive Manufacturing (AM) and Powder Metallurgy (PM) AlSi10Mg Alloys

Science.gov (United States)

Chen, B.; Moon, S. K.; Yao, X.; Bi, G.; Shen, J.; Umeda, J.; Kondoh, K.

2018-02-01

The microstructural and mechanical properties of AlSi10Mg alloys fabricated by additive manufacturing (AM) and powder metallurgy (PM) routes were investigated and compared. The microstructures were examined by scanning electron microscopy assisted with electron-dispersive spectroscopy. The crystalline features were studied by x-ray diffraction and electron backscatter diffraction. Room-temperature tensile tests and Vickers hardness measurements were performed to characterize the mechanical properties. It was found that the AM alloy had coarser Al grains but much finer Si precipitates compared with the PM alloy. Consequently, the AM alloy showed more than 100% increment in strength and hardness compared with the PM alloy due to the presence of ultrafine forms of Si, while exhibiting moderate ductility.

Computer-Adaptive Testing: Implications for Students' Achievement, Motivation, Engagement, and Subjective Test Experience

Science.gov (United States)

Martin, Andrew J.; Lazendic, Goran

2018-01-01

The present study investigated the implications of computer-adaptive testing (operationalized by way of multistage adaptive testing; MAT) and "conventional" fixed order computer testing for various test-relevant outcomes in numeracy, including achievement, test-relevant motivation and engagement, and subjective test experience. It did so…

On-line I{sup −}/Te{sup −} separation for the AMS analysis of {sup 125}I

Energy Technology Data Exchange (ETDEWEB)

Charles, C.R.J., E-mail: christopher.charles@uottawa.ca [Andre E. Lalonde Accelerator Mass Spectrometry Laboratory, Advanced Research Complex, University of Ottawa, 25 Templeton Street, Ottawa, ON K1N 6N5 (Canada); Cornett, R.J.; Zhao, X.-L. [Andre E. Lalonde Accelerator Mass Spectrometry Laboratory, Advanced Research Complex, University of Ottawa, 25 Templeton Street, Ottawa, ON K1N 6N5 (Canada); Litherland, A.E. [IsoTrace Laboratory, Department of Physics, University of Toronto, 60 St. George Street, Toronto, ON M5S 1A7 (Canada); Kieser, W.E. [Andre E. Lalonde Accelerator Mass Spectrometry Laboratory, Advanced Research Complex, University of Ottawa, 25 Templeton Street, Ottawa, ON K1N 6N5 (Canada)

2015-10-15

The isobar separator for anions (ISA) was used together with a 3 MV tandem accelerator mass spectrometer (AMS) to demonstrate the real time (on-line) separation of Te{sup −} from I{sup −}. Following the ion source mass spectrometry and major retardation to tens of eV, the ISA uses a radiofrequency quadrupole (RFQ) ion guide to confine and direct I{sup −} and associated Te{sup −} isobar anions through a gas-reaction cell, where chemical reactions occur at eV energies with the electronegative gas NO{sub 2}. Anions are subsequently reaccelerated out of the ISA to near original ion source extraction energies for AMS analysis. At 5 mTorr NO{sub 2} in the ISA gas-reaction cell, {sup 125}Te{sup −} was observed to be attenuated by a factor of ∼10{sup 7} as compared to {sup 127}I{sup −} that did not experience significant (<50%) losses. A comparative test using {sup 37}Cl{sup −} and {sup 32}S{sup −} (having similar chemical properties to iodine and tellurium) showed a {sup 32}S{sup −} attenuation of >10{sup 7} relative to {sup 37}Cl{sup −} under the same ISA–AMS conditions. The preferential destruction of Te{sup −} (and S{sup −}) at eV energies in the ISA is likely due to a larger favorable destruction cross-section with NO{sub 2}. This study is the first demonstration of I–Te anion separation for AMS, and makes possible the use of {sup 125}I, free of the contaminant {sup 125}Te isobar after suitable sample purification, for future {sup 129}I/{sup 125}I carrier-free analyses of natural samples at ultra-low trace levels.

The transmutation of americium: the Ecrix experiments in Phenix; Transmutation de l'americium: les experiences ecrix dans Phenix

Energy Technology Data Exchange (ETDEWEB)

Garnier, J C; Schmidt, N [CEA Cadarache, Dept. d' Etudes des Combustibles (DEC/SESC), 13 - Saint-Paul-lez-Durance (France); Croixmarie, Y; Ottaviani, J P [CEA Cadarache, Dept. d' Etudes des Combustibles (DEC/SPUA), 13 - Saint-Paul-lez-Durance (France); Varaine, F; Saint Jean, C de [CEA Cadarache, Dept. d' Etudes des Reacteurs (DER/SPRC), 13 - Saint-Paul-lez-Durance (France)

1999-07-01

The first americium transmutation experiment in a specific target in PHENIX will occur with the ECRIX-B and ECRIX-H experiments. Beside material testing, the objective is also to represent a concept of transmutation whose specificity is to enhance the kinetics of transmutation by using a moderated spectrum. The moderator materials will be {sup 11}B{sub 4}C and CaH{sub 2} for ECRIX-B and ECRIXH respectively, the irradiation conditions have been predicted for both the neutronics and thermal. The targets (MgO-AmO{sub X} pellets) are manufactured in the ATALANTE laboratory and the design is performed according to the PHENIX operating conditions. (authors)

Similarity of 241Am and 59Fe speciation in selected freshwaters and of their adsorption on crayfish exoskeleton

International Nuclear Information System (INIS)

Vangenechten, J.H.D.; Chughtai, N.A.; Bierkens, J.; Vanderborght, O.L.J.

1987-01-01

The particulate fraction and the organically complexed fraction of freshly added 241 Am and 59 Fe were determined in 21 prefiltered surface waters. The adsorptive behaviour of both radionuclides on a biological surface (isolated carapace segments of crayfish) was tested simultaneously. A striking similarity was observed in the chemical and absorptive behaviours of both radionuclides. The stoichiometry of particulate formation revealed a 3/4, Am to Fe ratio. This same stoichiometric relationship was observed in organic complexation, while adsorptive behaviour was characterised by a 1/1, Am to Fe ratio. It is concluded that Am predictably follows the chemistry of freshly added Fe at least over a 15 day period. This observation may find interesting application in risk assessment where use can be made of the well-known geochemical cycling of iron to predict the behaviour of man-made Am. (author)

Prisiones e internados: una comparación de los establecimientos penales en América del Norte y América Latina

Directory of Open Access Journals (Sweden)

Christopher Howard Birkbeck

Full Text Available El empleo reciente de términos como "warehouse prison" en Estados Unidos y "campo de concentración" en América Latina parecería indicar que las condiciones de privación de la libertad son distintas en ambas regiones. El análisis presentado aquí explora esas diferencias. Se comparan los establecimientos penales en América del Norte y América Latina a través de seis dimensiones relacionadas entre sí: la organización interna de los espacios, la vigilancia, el aislamiento, la supervisión, el control administrativo y la formalización de los procedimientos. En América del Norte, el control es asiduo (persistente, intrusivo y casi permanente; en América Latina, el control es somero (esporádico, indiferente y superficial. Si en América del Norte se habla de prisiones y encarcelamiento, en América Latina parece mejor hablar de internados judiciales e internación.

Neutron capture cross section of ^243Am

Science.gov (United States)

Jandel, M.

2009-10-01

The Detector for Advanced Neutron Capture Experiments (DANCE) at Los Alamos National Laboratory (LANL) was used for neutron capture cross section measurement on ^243Am. The high granularity of DANCE (160 BaF2 detectors in a 4π geometry) enables the efficient detection of prompt gamma-rays following neutron capture. DANCE is located on the 20.26 m neutron flight path 14 (FP14) at the Manuel Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center (LANSCE). The methods and techniques established in [1] were used for the determination of the ^243Am neutron capture cross section. The cross sections were obtained in the range of neutron energies from 0.02 eV to 400 keV. The resonance region was analyzed using SAMMY7 and resonance parameters were extracted. The results will be compared to existing evaluations and calculations. Work was performed under the auspices of the U.S. Department of Energy at Los Alamos National Laboratory by the Los Alamos National Security, LLC under Contract No. DE-AC52-06NA25396 and at Lawrence Livermore National Laboratory by the Lawrence Livermore National Security, LLC under Contract No. DE-AC52-07NA27344. [4pt] [1] M. Jandel et al., Phys. Rev. C78, 034609 (2008)

The SUERC AMS laboratory after 3 years

International Nuclear Information System (INIS)

Freeman, Stewart; Bishop, Paul; Bryant, Charlotte; Cook, Gordon; Dougans, Drew; Ertunc, Tanya; Fallick, Anthony; Ganeshram, Raja; Maden, Colin; Naysmith, Philip; Schnabel, Christoph; Scott, Marian; Summerfield, Michael; Xu Sheng

2007-01-01

The new SUERC AMS Laboratory was described at AMS-9. Since then there have been technological developments, added and improved analysis capability, the formation of additional complementary groups, the purchase of another instrument, and many samples measured. Be, C, Al, Cl, Ca and I-AMS are established with measured species changing weekly. Full-terminal potential running is now routine and 5 MV is proving sufficient for all species. Ion detection and evaluation has also been improved by the use of even thinner detector windows as necessary and a more powerful on-line data analysis system. Routine radiocarbon measurement is to 4 per mille reproducibility at middling current and graphite samples of as little as 100 μg C can be accommodated. Even smaller samples can be measured as CO 2 using He carrier in the gas capable ion source. Two new sample preparation laboratories at SUERC are the NERC Cosmogenic Isotope Analysis Facility and the SUERC/University of Glasgow Centre for Geosciences Cosmogenic Nuclide Laboratory. In particular these benefit from competitive Be-AMS and Cl-AMS performance

Indirect and inclusive search for dark matter with AMS02 space spectrometer; Recherche indirecte et inclusive de matiere noire avec le spectrometre spatial AMS02

Energy Technology Data Exchange (ETDEWEB)

Brun, P

2007-06-15

AMS02 is a particle physics detector designed for 3 years of data collecting aboard the International Space Station. Equipped with a superconducting magnet, it will allow to measure gamma and cosmic ray fluxes in the GeV to TeV region with high particle identification capabilities. Its performance is based on the redundancy of measurements in specific sub-detectors: a Time-Of-Flight counter, a Transition Radiation Detector, a Silicon Tracker, a Ring Imaging Cherenkov counter and an Electromagnetic calorimeter (Ecal). The Ecal is studied in details, in particular with the qualification of a stand-alone trigger devoted to gamma ray astronomy. This system allows the increase of the AMS02 sensitivity to photons, and the improvement of the reconstruction of electromagnetic events. The analog part of the trigger system has been tested with test benches and with a beam at CERN. The in-orbit calibration of the Ecal is studied, it may proceed in two steps. First, the Ecal cells responses have to be equalized with minimum ionizing particles data. Then an absolute calibration can be performed with cosmic electrons. For both the relative and the absolute calibration, possible procedures are defined and realistic calibration times are estimated. The second part deals with the indirect searches for dark matter and the study of the AMS02 sensitivity. Dark matter stands for 84% of the Universe mass and could consist in new particles. Dark matter particles are expected to surround our Galaxy and annihilate in high density regions. These annihilations could become observable exotic primary cosmic ray sources. Searches for anomalous excesses in (p-bar, e{sup +}, D-bar) and {gamma} ray fluxes will be performed by AMS02. A numerical tool allowing us to perform predictions for these exotic fluxes within supersymmetry or extra-dimension is developed and is presented in details. Phenomenological studies regarding possible enhancements of these signals by over-dense regions of the halo

ROSA/LSTF Test and RELAP5 Analyses on PWR Cold Leg Small-Break LOCA with Accident Management Measure and PKL Counterpart Test

Energy Technology Data Exchange (ETDEWEB)

Takeda, Takeshi; Ohtsu, Iwao [Nuclear Safety Research Center, Japan Atomic Energy Agency, Tokaimura (Japan)

2017-08-15

An experiment using the Primaerkreislaeufe Versuchsanlage (PKL) was performed for the OECD/NEA PKL-3 Project as a counterpart to a previous test with the large-scale test facility (LSTF) on a cold leg small-break loss-of-coolant accident with an accident management (AM) measure in a pressurized water reactor. Concerning the AM measure, the rate of steam generator (SG) secondary-side depressurization was controlled to achieve a primary depressurization rate of 200 K/h as a common test condition; however, the onset timings of the SG depressurization were different from each other. In both tests, rapid recovery started in the core collapsed liquid level after loop seal clearing, which caused whole core quench. Some discrepancies appeared between the LSTF and PKL test results for the core collapsed liquid level, the cladding surface temperature, and the primary pressure. The RELAP5/MOD3.3 code predicted the overall trends of the major thermal-hydraulic responses observed in the LSTF test well, and indicated a remaining problem in the prediction of primary coolant distribution. Results of uncertainty analysis for the LSTF test clarified the influences of the combination of multiple uncertain parameters on peak cladding temperature within the defined uncertain ranges.

ROSA/LSTF Test and RELAP5 Analyses on PWR Cold Leg Small-Break LOCA with Accident Management Measure and PKL Counterpart Test

Directory of Open Access Journals (Sweden)

Takeshi Takeda

2017-08-01

Full Text Available An experiment using the Primӓrkreislӓufe Versuchsanlage (PKL was performed for the OECD/NEA PKL-3 Project as a counterpart to a previous test with the large-scale test facility (LSTF on a cold leg small-break loss-of-coolant accident with an accident management (AM measure in a pressurized water reactor. Concerning the AM measure, the rate of steam generator (SG secondary-side depressurization was controlled to achieve a primary depressurization rate of 200 K/h as a common test condition; however, the onset timings of the SG depressurization were different from each other. In both tests, rapid recovery started in the core collapsed liquid level after loop seal clearing, which caused whole core quench. Some discrepancies appeared between the LSTF and PKL test results for the core collapsed liquid level, the cladding surface temperature, and the primary pressure. The RELAP5/MOD3.3 code predicted the overall trends of the major thermal-hydraulic responses observed in the LSTF test well, and indicated a remaining problem in the prediction of primary coolant distribution. Results of uncertainty analysis for the LSTF test clarified the influences of the combination of multiple uncertain parameters on peak cladding temperature within the defined uncertain ranges.

Chemical thermodynamic representation of (U, Pu, Am)O2-x

International Nuclear Information System (INIS)

Osaka, Masahiko; Namekawa, Takashi; Kurosaki, Ken; Yamanaka, Shinsuke

2005-01-01

The oxygen potential isotherms of (U, Pu, Am)O 2-x were represented by a chemical thermodynamic model proposed by Lindemer et al. It was assumed in the present model that (U, Pu, Am)O 2-x consisted of the chemical species [UO 2 ], [PuO 2 ], [Pu 4/3 O 2 ], [AmO 2 ] and [Am 5/4 O 2 ] in a pseudo-quaternary system by treating the reduction rates of Pu and Am as identical; furthermore an interaction between [Am 5/4 O 2 ] and [UO 2 ] was introduced. The agreement between analytical and experimental isotherms was good, but the analytical values slightly overestimated the experimental values especially in the case of lower Am content. Adding an interaction between [Am 5/4 O 2 ] and [PuO 2 ] to the model resulted in a better representation

Indirect and inclusive search for dark matter with AMS02 space spectrometer; Recherche indirecte et inclusive de matiere noire avec le spectrometre spatial AMS02

Energy Technology Data Exchange (ETDEWEB)

Brun, Pierre [Laboratoire d' Annecy-le-vieux de Physique des Particules, Chemin de Bellevue, BP 110, 74941 Annecy-le-Vieux Cedex (France)

2007-07-01

AMS02 is a particle physics detector designed for 3 years of data taking aboard the International Space Station. Equipped with a superconducting magnet, it will allow to measure gamma and cosmic ray fluxes in the GeV to TeV region with high particle identification capabilities. Its performance is based on the redundancy of measurements in specific sub-detectors: a Time-Of-Flight counter, a Transition Radiation Detector, a Silicon Tracker, a Ring Imaging Cherenkov counter and an Electromagnetic calorimeter (Ecal). The Ecal is studied in details, in particular with the qualification of a stand-alone trigger devoted to gamma ray astronomy. This system allows to increase the AMS02 sensitivity to photons, and to improve the reconstruction of electromagnetic events. The analog part of the trigger system has been tested with test benches and in-beam at CERN. The in-orbit calibration of the Ecal is studied, it may proceed in two steps. First, the Ecal cells responses have to be equalized with minimum ionizing particles data. Then an absolute calibration can be performed with cosmic electrons. For both the relative and the absolute calibration, possible procedures are defined and realistic calibration times are estimated. The second part deals with the indirect searches for dark matter and the study of the AMS02 sensitivity. Dark matter stands for 84% of the Universe mass and could consist in new particles. Dark matter particles are expected to surround our Galaxy and annihilate in high density regions. These annihilations could become observable exotic primary cosmic ray sources. Searches for anomalous excesses in (p-bar, e{sup +}, D-bar) and {gamma} ray fluxes will be performed by AMS02. A numerical tool allowing to perform predictions for these exotic fluxes within supersymmetry or extra-dimension is developed and is presented in details. Phenomenological studies regarding possible enhancements of these signals by over-dense regions of the halo have also been performed

Rapid change of AM fungal community in a rain-fed wheat field with short-term plastic film mulching practice.

Science.gov (United States)

Liu, Yongjun; Mao, Lin; He, Xinhua; Cheng, Gang; Ma, Xiaojun; An, Lizhe; Feng, Huyuan

2012-01-01

Plastic film mulching (PFM) is a widely used agricultural practice in the temperate semi-arid Loess Plateau of China. However, how beneficial soil microbes, arbuscular mycorrhizal (AM) fungi in particular, respond to the PFM practice is not known. Here, a field experiment was performed to study the effects of a 3-month short-term PFM practice on AM fungi in plots planted with spring wheat (Triticum aestivum L. cv. Dingxi-2) in the Loess Plateau. AM colonization, spore density, wheat spike weight, and grain phosphorus (P) content were significantly increased in the PFM treatments, and these changes were mainly attributable to changes in soil properties such as available P and soil moisture. Alkaline phosphatase activity was significantly higher in PFM soils, but levels of AM fungal-related glomalin were similar between treatments. A total of nine AM fungal phylotypes were detected in root samples based on AM fungal SSU rDNA analyses, with six and five phylotypes in PFM and no-PFM plots, respectively. Although AM fungal phylotype richness was not statistically different between treatments, the community compositions were different, with four and three specific phylotypes in the PFM and no-PFM plots, respectively. A significant and rapid change in AM fungal, wheat, and soil variables following PFM suggested that the functioning of the AM symbiosis had been changed in the wheat field under PFM. Future studies are needed to investigate whether PFM applied over a longer term has a similar effect on the AM fungal community and their functioning in an agricultural ecosystem.

Development flight tests of JetStar LFC leading-edge flight test experiment

Science.gov (United States)

Fisher, David F.; Fischer, Michael C.

1987-01-01

The overall objective of the flight tests on the JetStar aircraft was to demonstrate the effectiveness and reliability of laminar flow control under representative flight conditions. One specific objective was to obtain laminar flow on the JetStar leading-edge test articles for the design and off-design conditions. Another specific objective was to obtain operational experience on a Laminar Flow Control (LFC) leading-edge system in a simulated airline service. This included operational experience with cleaning requirements, the effect of clogging, possible foreign object damage, erosion, and the effects of ice particle and cloud encounters. Results are summarized.

Adaptation of the Activity Measure Post-Acute Care (AM-PAC) from English to Mandarin using the dual-panel translation approach

DEFF Research Database (Denmark)

Chang, Feng-Hang; Liou, Tsan-Hon; Brodersen, John

2017-01-01

translated using the dual-panel method. The translated AM-PAC was tested in 550 Chinese-speaking rehabilitation outpatients. Floor and ceiling effects were evaluated and internal consistency was assessed using Cronbach's alpha. Spearman correlation was used to assess the concurrent validity of the AM...

L1 track trigger for the CMS HL-LHC upgrade using AM chips and FPGAs

CERN Document Server

Fedi, Giacomo

2017-01-01

The increase of luminosity at the HL-LHC will require the introduction of tracker information in CMS's Level-1 trigger system to maintain an acceptable trigger rate when selecting interesting events, despite the order of magnitude increase in minimum bias interactions. To meet the latency requirements, dedicated hardware has to be used. This paper presents the results of tests of a prototype system (pattern recognition mezzanine) as core of pattern recognition and track fitting for the CMS experiment, combining the power of both associative memory custom ASICs and modern Field Programmable Gate Array (FPGA) devices. The mezzanine uses the latest available associative memory devices (AM06) and the most modern Xilinx Ultrascale FPGAs. The results of the test for a complete tower comprising about 0.5 million patterns is presented, using as simulated input events traversing the upgraded CMS detector. The paper shows the performance of the pattern matching, track finding and track fitting, along with the latency...

40 CFR 60.4240 - What are my compliance requirements if I am a manufacturer of stationary SI internal combustion...

Science.gov (United States)

2010-07-01

... I am a manufacturer of stationary SI internal combustion engines >19 KW (25 HP) that are rich burn... I am a manufacturer of stationary SI internal combustion engines >19 KW (25 HP) that are rich burn..., and must test their engines as specified in that part. Stationary SI internal combustion engine...

Detection of Pu in Pacific Ocean water with AMS related to the Fukushima accident

Energy Technology Data Exchange (ETDEWEB)

Hain, Karin; Faestermann, Thomas; Fimiani, Leticia; Guzman, Jose Manuel; Korschinek, Gunther; Kortmann, Florian; Lierse v Gostomski, Christoph; Ludwig, Peter [TUM (Germany); Golser, Robin; Steier, Peter [Universitaet Wien (Austria); Yamada, Masatoshi [Hirosaki University (Japan)

2016-07-01

The concentration of plutonium (Pu) and its isotopic ratios were determined by accelerator mass spectrometry (AMS) in Pacific Ocean water samples. The isotopic ratios {sup 240}Pu/{sup 239}Pu and {sup 241}Pu/{sup 239}Pu can be used to identify a possible release of Pu into the ocean by the Fukushima accident. {sup 241}Pu from fallout of nuclear weapon testings has already significantly decayed. {sup 241}Am, the daughter nuclide of {sup 241}Pu, causes isobaric background on {sup 241}Pu in mass-spectrometric measurements. Therefore, Am and Pu had to be separated chemically using extraction chromatography. The method was verified by analyzing certified reference material. 12 sea water samples, collected at different depths, were prepared at the Radiochemie Muenchen. The concentration of Pu was measured with AMS at the Maier-Leibnitz-Laboratory in Munich and the Vienna Environmental Research Laboratory (VERA). After a short motivation related to the Fukushima accident, the chemical separation method will be presented. Preliminary results of the distribution of Pu in ocean water will be discussed.

Strain rate effects of AM60

International Nuclear Information System (INIS)

Rehkopf, J.D.; Krause, A.R.

2002-01-01

Magnesium is seeing increasing use in the automotive industry due to its high strength-to-weight ratio and its ability to be cast to tight dimensional tolerances. Presently, main applications include interior components such as instrument panels, steering wheels and seat frames. Consequently, there is a strong need for understanding the rate effect on the behaviour of magnesium under impact type loading. In this work the effect of strain rate on AM60 tensile behaviour was investigated through both high and cold temperature testing, at ranges relevant to the automotive environment. Microstructural analysis, presented in this paper, includes porosity, grain size and fracture surface analyses. (author)

Sorption of 241Am onto montmorillonite, illite and hematite colloids

International Nuclear Information System (INIS)

Degueldre, C.; Ulrich, H.J.; Silby, H.

1994-01-01

Actinide sorption on colloids may be described as a competition between the formation of complexes in solution and the build up of surface complexes. The role of particle and of carbonate concentrations on the sorption/desorption of 241 Am on montmorillonite, illite and hematite colloids is investigated. Since the partition coefficient (K p ) values are virtually independent of the colloid concentrations, within the range 1 to 300 ppm, no significant aggregation takes place in the sorption/desorption experiment. At pH 8, a slight decrease of K p is observed if the concentration of total carbonate exceeds 10 -2 M. The formation of the carbonato- (and hydroxo-carbonato-) complexes in the solution competes with the formation of surface complexes on the colloids. A relationship between the sorption coefficient and the complexation of 241 Am in the solution has been found. This leads to the conclusion that, besides free americium cation, the hydroxo-, and carbonato- as well as the mixed hydroxo-carbonato-complexes are sorbed. Only when the tricarbonatocomplex [Am(CO 3 ) 3 ] 3- prevails (total carbonate concentration > 10 -2 M), a significant decrease of the distribution coefficient is observed. At pH 10 this decrease disappears because under these conditions the strong hydroxo-complexes dominate. A pragmatic and relatively simple application of surface complexation model describes the observed features. (orig.)

The transmutation of americium: the Ecrix experiments in Phenix; Transmutation de l'americium: les experiences ecrix dans Phenix

Energy Technology Data Exchange (ETDEWEB)

Garnier, J.C.; Schmidt, N. [CEA Cadarache, Dept. d' Etudes des Combustibles (DEC/SESC), 13 - Saint-Paul-lez-Durance (France); Croixmarie, Y.; Ottaviani, J.P. [CEA Cadarache, Dept. d' Etudes des Combustibles (DEC/SPUA), 13 - Saint-Paul-lez-Durance (France); Varaine, F.; Saint Jean, C. de [CEA Cadarache, Dept. d' Etudes des Reacteurs (DER/SPRC), 13 - Saint-Paul-lez-Durance (France)

1999-07-01

The first americium transmutation experiment in a specific target in PHENIX will occur with the ECRIX-B and ECRIX-H experiments. Beside material testing, the objective is also to represent a concept of transmutation whose specificity is to enhance the kinetics of transmutation by using a moderated spectrum. The moderator materials will be {sup 11}B{sub 4}C and CaH{sub 2} for ECRIX-B and ECRIXH respectively, the irradiation conditions have been predicted for both the neutronics and thermal. The targets (MgO-AmO{sub X} pellets) are manufactured in the ATALANTE laboratory and the design is performed according to the PHENIX operating conditions. (authors)

Application of accelerator mass spectrometry to environmental research, Trial of GC-AMS

International Nuclear Information System (INIS)

Shibata, Yasuyuki

2003-01-01

The accelerator analysis facility of the National Institute for Environmental Studies, which aims to develop a new device capable of measuring "1"4C age for each compound, is promoting the study to establish the GC-AMS that combines two-dimensional gas chromatograph (GC) and accelerator mass spectrometry (AMS). The on-line GC-AMS system for the metabolic measurement of "1"4C-labeled compounds for medicinal biochemical research is a system, in which a GC-separated sample is continuously converted into CO_2 in a combustion tube and introduced directly to a gas ion source to continuously measure "1"4C. In the "1"4C detection experiment, the concentration of CO_2 gas was changed using a helium introduction line and a sample injection valve, and CO_2 gas plus helium gas were introduced into the gas ion source. As a result, it was found that the online GC-AMS has feasibility and high potential capability. For off-line GC-AMS for environmental samples, after purification with preparative gas chromatography, the sample is converted to graphite in a vacuum line and applied to common AMS measurement. The authors collected Northwest Pacific Ocean bottom sediment cores, and performed the extraction and purification of fatty acids of specific stratigraphy and the "1"4C measurement of each compound. The age of the compound derived from the surface layer planktons was the result capable of indicating the sedimentary age of the stratigraphy. In addition, as an application study to explore the source of pollutants in the environment using "1"4C as a tracer representing the characteristics of each source, the authors started to conduct the research choosing atmospheric dust samples. As a starting point, the authors attempted to measure the "1"4C concentration of vehicle exhaust particles and incinerator fly ash particles respectively. There was hardly any "1"4C in vehicle exhaust particles. (A.O.)

Prof. Samuel ting presents results from AMS experiment at CERN main auditorium. Geneva 3 April 2013. The international team running the Alpha Magnetic Spectrometer (AMS1) today announced the first results in its search for dark matter

CERN Multimedia

Samuel Morier-Genoud

2013-01-01

Geneva 3 April 2013. The international team running the Alpha Magnetic Spectrometer (AMS) today announced the first results in its search for dark matter. The results, presented by AMS spokesperson Professor Samuel Ting in a seminar at CERN, are to be published in the journal Physical Review Letters. They report the observation of an excess of positrons in the cosmic ray flux

Analysis of Windscale and Bikini atoll sediments for Am-242m

International Nuclear Information System (INIS)

Beasley, T.M.

1976-01-01

Bowen and Livingston have recently reported the existence of 242 Am in both 1962 nuclear test debris and in a marine algae sample (kelp) contaminated by nuclear fuel reprocessing wastes. The presence of 242m Am (T 1/2 = 152y) was deduced by measuring its daughter product, 242C m. In the case of the fallout debris, the long decay time (25 years) between collection and analysis was argued to preclude the possibility of unsupported 242 Cm being present in the sample. The non-adherence to simple radiometric decay of the 242 Cm measured in two aliquots of the algae sample suggested that a small percentage of the isotope (≈ 3%) was in fact supported by its longer lived parent

Effect of arbuscular mycorrhizal (AM) fungi on 137Cs uptake by plants grown on different soils

International Nuclear Information System (INIS)

Vinichuk, M.; Mårtensson, A.; Ericsson, T.; Rosén, K.

2013-01-01

The potential use of mycorrhiza as a bioremediation agent for soils contaminated by radiocesium was evaluated in a greenhouse experiment. The uptake of 137 Cs by cucumber, perennial ryegrass, and sunflower after inoculation with a commercial arbuscular mycorrhizal (AM) product in soils contaminated with 137 Cs was investigated, with non-mycorrhizal quinoa included as a “reference” plant. The effect of cucumber and ryegrass inoculation with AM fungi on 137 Cs uptake was inconsistent. The effect of AM fungi was most pronounced in sunflower: both plant biomass and 137 Cs uptake increased on loamy sand and loamy soils. The total 137 Cs activity accumulated within AM host sunflower on loamy sand and loamy soils was 2.4 and 3.2-fold higher than in non-inoculated plants. Although the enhanced uptake of 137 Cs by quinoa plants on loamy soil inoculated by the AM fungi was observed, the infection of the fungi to the plants was not confirmed. - Highlights: ► Effect of soil inoculation on 137 Cs uptake by crops was studied in greenhouse. ► 137 Cs uptake by inoculated sunflower plants was most pronounced. ► The higher 137 Cs uptake by inoculated sunflower due to presence of mycorrhiza. ► Studies suggest potential for use of mycorrhiza on contaminated sites.

Sorption of 241Am by Aspergillus niger spore and hyphae

International Nuclear Information System (INIS)

Yuanyou Yang; Ning Liu; Jiali Liao; Jiannan Jin; Shunzhong Luo; Taiming Zhang; Pengji Zhao

2004-01-01

Biosorption of 241 Am by a fungus A. niger, including the spore and hyphae, was investigated. The preliminary results showed that the adsorption of 241 Am by the microorganism was efficient. More than 96% of the total 241 Am could be removed from 241 Am solutions of 5.6-111 MBq/l (C 0 ) by spore and hyphae of A. niger, with adsorbed 241 Am metal (Q) of 7.2-142.4 MBq/g biomass, and 5.2-106.5 MBq/g, respectively. The biosorption equilibrium was achieved within 1 hour and the optimum pH range was pH 1-3. No obvious effects on 241 Am adsorption by the fungus were observed at 10-45 deg C, or in solutions containing Au 3+ or Ag + , even 2000 times above the 241 Am concentration. The 241 Am biosorption by the fungus obeys the Freundlich adsorption equation. There was no significant difference between the adsorption behavior of A. niger spore and hyphae. (author)

A teststand for photo detectors and beamtests for ILC polarimetry; Aufbau eines Teststandes fuer Photodetektoren und Teststrahlmessungen fuer die Strahlpolarisationsmessung am ILC

Energy Technology Data Exchange (ETDEWEB)

Velte, Ulrich

2009-02-15

In the future International Linear Collider (ILC) up to 80% polarized electrons shall be brought to collision with up to 60% polarized positrons. Because the cross sections of the resulting reactions depend sensitively on the beam polarization this must be measured with a hitherto never reached accuracy of {delta}P/P{approx}0.25%. This shall be reached via Compton scattering of laser photons from the beam particles and subsequent detection of the scattered electrons in a Cherenkov hodoscope. Content of this thesis was to build a teststand, in which different photodetectors for the detection of the Cherenkov light can be characterized and checked on their suitability for the special application in the ILC polarimeter. The until now best polarization measurement was reached in the framework of the SLD experiment at SLAC in California ({delta}P/P{approx}0.5%). At present the Cherenkov counter of the SLD polarimeter is at DESY and is their used in order to measure different photodetectors coming into question for the ILC polarimetry in the test beam. In order to be able to continue the experiences from the SLD experiment in the framework of this thesis test-beam measurements at the Cherenkov detector are evaluated and the first developments towards a polarimeter for the ILC described. [German] Im zukuenftigen International Linear Collider (ILC) sollen bis zu 80% polarisierte Elektronen mit bis zu 60% polarisierten Positronen zur Kollision gebracht werden. Da die Wirkungsquerschnitte der resultierenden Reaktionen empfindlich von der Strahlpolarisation abhaengen, muss diese mit einer bisher nie erreichten Genauigkeit von {delta}P/P{approx}0.25% gemessen werden. Dies soll ueber Compton-Streuung von Laserphotonen an den Strahlteilchen und anschliessendem Nachweis der gestreuten Elektronen in einem Cerenkov-Hodoskop erreicht werden. Inhalt dieser Arbeit war es, einen Teststand aufzubauen, in dem verschiedenartige Photodetektoren zum Nachweis des Cerenkov

A decade of AMS at University of Georgia

International Nuclear Information System (INIS)

Culp, Randy; Noakes, John; Cherkinsky, Alex; Ravi Prasad, G.V.; Dvoracek, Doug

2013-01-01

In a span of 10 years, University of Georgia’s Center for Applied Isotope Studies (CAIS) has transformed itself from principally a liquid scintillation counting (LSC) laboratory to one conducting thousands of accelerator mass spectrometry (AMS) and stable isotope ratio analysis (SIRA) annually. After receiving the first of the NEC compact AMS units in the United States, the CAIS began to meet the demand for 14 C analysis outside the normal realm of most radiocarbon dating laboratories. With industry’s support, isotope research continued on an already developing natural products program to authenticate materials origin and process of formation. The CAIS’s AMS allowed for the detection of synthetic materials in milligram quantities rather than gram quantities required by LSC and allowed new compound specific SIRA techniques to be directed toward compound specific 14 C measurement. By 2005 the CAIS was one of only a few laboratories accredited to determine bio-base content in industrial fuels and products by both AMS and LSC following ASTM D6866-10 [1]. Since 2001, when our first sample was analyzed by AMS method, both radiocarbon and natural products sample numbers have increased steadily. The advantages of AMS analysis in overall efficiency, cost savings, accuracy, and precision, are detailed here in a review of analytical precision for radiocarbon and natural products analyzed over 10 years of AMS operation. Comparisons are made between natural products and bio-based materials analyzed by both AMS and LSC. Although high precision is not required to authenticate natural products, for the purpose of product comparison with regard to degree of naturalness accurate and precise 14 C measurement is shown to be achievable by both methods.

Software development for continuous-gas-flow AMS

International Nuclear Information System (INIS)

Reden, K.F. von; Roberts, M.L.; Jenkins, W.J.; Rosenheim, B.E.; McNichol, A.P.; Schneider, R.J.

2008-01-01

The National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) Facility at Woods Hole Oceanographic Institution is presently completing installation of a novel continuous-flow AMS system. A multi-year development of an AMS microwave gas ion source in collaboration with Atomic Energy Canada Limited (AECL), Chalk River, has preceded this final step of an implementation that is expected to add a new dimension to 14 C AMS. National Instruments, NIM, and CAMAC modules have been programmed with LabVIEW on a Windows XP platform to form the basis for data acquisition. In this paper we discuss possible applications and include simulations of expected data acquisition scenarios like real-time AMS analysis of chromatograms. Particular attention will have to be given to issues of synchronization between rapidly changing input amplitudes and signal processing cycles in hardware and software

Manufacturing and testing experience for FFTF major safety related components

International Nuclear Information System (INIS)

Peckinpaugh, C.L.

1976-01-01

Experience with FFTF Heat Transport System components during design, manufacturing, and prototype testing is dscussed. Specifically the special design features and the results of the testing performed to assure that the designs provide for safe operation are outlined. Particular emphasis is placed on the full size prototype testing programs and the valuable experience gained

Changes of AM fungal abundance along environmental gradients in the arid and semi-arid grasslands of northern China.

Directory of Open Access Journals (Sweden)

Yajun Hu

Full Text Available Arbuscular mycorrhizal (AM fungi are ubiquitous symbionts of higher plants in terrestrial ecosystems, while the occurrence of the AM symbiosis is influenced by a complex set of abiotic and biotic factors. To reveal the regional distribution pattern of AM fungi as driven by multiple environmental factors, and to understand the ecological importance of AM fungi in natural ecosystems, we conducted a field investigation on AM fungal abundance along environmental gradients in the arid and semi-arid grasslands of northern China. In addition to plant parameters recorded in situ, soil samples were collected, and soil chemo-physical and biological parameters were measured in the lab. Statistical analyses were performed to reveal the relative contribution of climatic, edaphic and vegetation factors to AM fungal abundance, especially for extraradical hyphal length density (HLD in the soil. The results indicated that HLD were positively correlated with mean annual temperature (MAT, soil clay content and soil pH, but negatively correlated with both soil organic carbon (SOC and soil available N. The multiple regressions and structural equation model showed that MAT was the key positive contributor and soil fertility was the key negative contributor to HLD. Furthermore, both the intraradical AM colonization (IMC and relative abundance of AM fungi, which was quantified by real-time PCR assay, tended to decrease along the increasing SOC content. With regard to the obvious negative correlation between MAT and SOC in the research area, the positive correlation between MAT and HLD implied that AM fungi could potentially mitigate soil carbon losses especially in infertile soils under global warming. However, direct evidence from long-term experiments is still expected to support the AM fungal contribution to soil carbon pools.

HIV testing and counseling: test providers' experiences of best practices.

Science.gov (United States)

Myers, Ted; Worthington, Catherine; Haubrich, Dennis J; Ryder, Karen; Calzavara, Liviana

2003-08-01

Although education is central to HIV testing and counseling, little is known about the educational processes within the testing experience. This study investigated test providers' understandings of testing and counseling best practices. Interviews with a purposive sample of 24 test providers were thematically analyzed. Analysis revealed five best practices specific to HIV education and public health--ensuring information and education for HIV risk reduction, individualization of risk assessment, ensuring test results are given in person, providing information and referrals, and facilitating partner notification--and six practices not specific to HIV counseling relationship building. The latter were building trust and rapport; maintaining professional boundaries; ensuring a comfortable, safe environment; ensuring confidentiality; imparting nonjudgmntal attitude; and self-determination. The identified best practices demonstrated remarkable consistency across respondent subgroups. Although counseling was seen as largely educational and with a preventive focus, it included individualized messages based on assessments of risk, knowledge, and social and cultural characteristics.

Enhancing TRU burning and Am transmutation in Advanced Recycling Reactor

International Nuclear Information System (INIS)

Ikeda, Kazumi; Kochendarfer, Richard A.; Moriwaki, Hiroyuki; Kunishima, Shigeru

2011-01-01

Research highlights: → This ARR is an oxide fueled sodium cooled reactor based on innovative technologies to destruct TRU. → TRU burning core is designed to burn TRU at 28 kg/TW th h, adding moderator pins of B 4 C (Enriched B-11). → Am transmutation core can transmute Am at 34 kg/TW th h, adding uranium free AmN blanket to TRU burning core. → The TRU burning core improves TRU burning by 40-50% than the previous core. → The Am transmutation core can transmute Am effectively, keeping the void reactivity acceptable. - Abstract: This paper presents about conceptual designs of Advanced Recycling Reactor (ARR) focusing on enhancement in transuranics (TRU) burning and americium (Am) transmutation. The design has been conducted in the context of the Global Nuclear Energy Partnership (GNEP) seeking to close nuclear fuel cycle in ways that reduce proliferation risks, reduce the nuclear waste in the US and further improve global energy security. This study strives to enhance the TRU burning and the Am transmutation, assuming the development of related technologies in this study, while the ARR based on mature technologies was designed in the previous study. It has followed that the provided TRU burning core is designed to burn TRU at 28 kg/TW th h, by adding moderator pins of B 4 C (Enriched B-11) and the Am transmutation core will be able to transmute Am at 34 kg/TW th h, by locating Am blanket of AmN around the TRU burning core. It indicates that these concepts improve TRU burning by 40-50% than the previous core and can transmute Am effectively, keeping the void reactivity acceptable.

Results of Am isotopic ratio analysis in irradiated MOX fuels

Energy Technology Data Exchange (ETDEWEB)

Koyama, Shin-ichi; Osaka, Masahiko; Mitsugashira, Toshiaki; Konno, Koichi [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center; Kajitani, Mikio

1997-04-01

For analysis of a small quantity of americium, it is necessary to separate from curium which has similar chemical property. As a chemical separation method for americium and curium, the oxidation of americium with pentavalent bismuth and subsequent co-precipitation of trivalent curium with BIP O{sub 4} were applied to analyze americium in irradiated MOX fuels which contained about 30wt% plutonium and 0.9wt% {sup 241}Am before irradiation and were irradiated up to 26.2GWd/t in the experimental fast reactor Joyo. The purpose of this study is to measure isotopic ratio of americium and to evaluate the change of isotopic ratio with irradiation. Following results are obtained in this study. (1) The isotopic ratio of americium ({sup 241}Am, {sup 242m}Am and {sup 243}Am) can be analyzed in the MOX fuels by isolating americium. The isotopic ratio of {sup 242m}Am and {sup 243}Am increases up to 0.62at% and 0.82at% at maximum burnup, respectively, (2) The results of isotopic analysis indicates that the contents of {sup 241}Am decreases, whereas {sup 242m}Am, {sup 243}Am increase linearly with increasing burnup. (author)

'Not the swab!' Young men's experiences with STI testing.

Science.gov (United States)

Shoveller, Jean A; Knight, Rod; Johnson, Joy; Oliffe, John L; Goldenberg, Shira

2010-01-01

In Canada, STI rates are high and rising, especially amongst young men. Meanwhile, the needs of young men regarding STI testing services are poorly understood, as are the socio-cultural and structural factors that influence young men's sexual health-seeking behaviours. To better understand this phenomenon, we draw on interviews with 45 men (ages 15-25) from British Columbia, Canada. Our research reveals how structural forces (e.g. STI testing procedures) interact with socio-cultural factors (e.g. perceptions of masculinities and feminities) to shape young men's experiences with STI testing. STI testing was characterised as both a potentially sexualised experience (e.g. fears of getting an erection during genital examinations), and as a process where young men experience multiple vulnerabilities associated with exposing the male body in clinical service sites. In response, participants drew on dominant ideals of masculinity to reaffirm their predominately hetero-normative gender identities. Despite growing up in an era where sexual health promotion efforts have been undertaken, participants did not feel they had permission to engage in discussions with other men about sexual health issues. Attending to young men's perspectives on STI testing represents a starting point in reforming our approaches to addressing how socio-cultural and structural factors shape these experiences.

Laboratory column experiments for radionuclide adsorption studies of the Culebra dolomite member of the Rustler Formation

Energy Technology Data Exchange (ETDEWEB)

Lucero, D.A.; Heath, C.E. [Sandia National Labs., Albuquerque, NM (United States); Brown, G.O. [Oklahoma State Univ., Stillwater, OK (United States). Biosystems and Agricultural Engineering Dept.

1998-04-01

Radionuclide transport experiments were carried out using intact cores obtained from the Culebra member of the Rustler Formation inside the Waste Isolation Pilot Plant, Air Intake Shaft. Twenty-seven separate tests are reported here and include experiments with {sup 3}H, {sup 22}Na, {sup 241}Am, {sup 239}Np, {sup 228}Th, {sup 232}U and {sup 241}Pu, and two brine types, AIS and ERDA 6. The {sup 3}H was bound as water and provides a measure of advection, dispersion, and water self-diffusion. The other tracers were injected as dissolved ions at concentrations below solubility limits, except for americium. The objective of the intact rock column flow experiments is to demonstrate and quantify transport retardation coefficients, (R) for the actinides Pu, Am, U, Th and Np, in intact core samples of the Culebra Dolomite. The measured R values are used to estimate partition coefficients, (kd) for the solute species. Those kd values may be compared to values obtained from empirical and mechanistic adsorption batch experiments, to provide predictions of actinide retardation in the Culebra. Three parameters that may influence actinide R values were varied in the experiments; core, brine and flow rate. Testing five separate core samples from four different core borings provided an indication of sample variability. While most testing was performed with Culebra brine, limited tests were carried out with a Salado brine to evaluate the effect of intrusion of those lower waters. Varying flow rate provided an indication of rate dependent solute interactions such as sorption kinetics.

Space Shuttle Boundary Layer Transition Flight Experiment Ground Testing Overview

Science.gov (United States)

Berger, Karen T.; Anderson, Brian P.; Campbell, Charles H.

2014-01-01

In support of the Boundary Layer Transition (BLT) Flight Experiment (FE) Project in which a manufactured protuberance tile was installed on the port wing of Space Shuttle Orbiter Discovery for STS-119, STS- 128, STS-131 and STS-133 as well as Space Shuttle Orbiter Endeavour for STS-134, a significant ground test campaign was completed. The primary goals of the test campaign were to provide ground test data to support the planning and safety certification efforts required to fly the flight experiment as well as validation for the collected flight data. These test included Arcjet testing of the tile protuberance, aerothermal testing to determine the boundary layer transition behavior and resultant surface heating and planar laser induced fluorescence (PLIF) testing in order to gain a better understanding of the flow field characteristics associated with the flight experiment. This paper provides an overview of the BLT FE Project ground testing. High-level overviews of the facilities, models, test techniques and data are presented, along with a summary of the insights gained from each test.

A TRLFS Study on the Interactions of Am(III) at the Interface of Water and Silica Nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Kim, Hee-Kyung; Jung, Euo Chang; Cho, Hye-Ryun; Cha, Wansik [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

In this study, we employed time-resolved laser-induced fluorescence spectroscopy (TRLFS) to characterize Am(III) interactions with SiO{sub 2} nanoparticles at a molecular level. TRLFS results show that adsorption of Am(III) onto the silica broadens the luminescence spectra with red-shifts of 2-3 nm. Luminescence lifetime measurements show the increase in the lifetime from 23.5 ± 0.3 ns to ⁓37 ns as the pH increases from 2.5 to 8 or above. The observations indicate that adsorption takes place via inner-sphere bindings by displacing about four inner-sphere bound water molecules. At the pH 7 and above, additional longer lifetime (> 100 ns) component was identified, which corresponds to displacing all the inner-sphere water molecules. We will discuss more details on the spectral characteristics of the adsorbed Am(III) and their implications. Adsorption of Am(III) onto silica nanoparticles was studied as a function of the pH by using batch-sorption experiments and TRLFS. TRLFS results show that adsorbed Am(III) displays broadened luminescence spectra with longer lifetimes compared to those of the aqueous species, indicating that adsorption takes place via formation of inner-sphere surface complexes. Our data also suggest that at least two different types of Am(III)-silica species are present at the pH above 7.

Transmutation of 129I, 237Np, 238Pu, 239Pu, and 241Am using ...

Indian Academy of Sciences (India)

Results of transmutation studies of 129I, 237Np, 238Pu, 239Pu and 241Am are presented. Keywords. ... J Adam et al. Table 1. Samples properties for 0.7 and 1 GeV experiments. ..... If we suppose that this conclusion is true also for ratios in ...

Total and (n, 2n) neutron cross section measurements on 241Am

International Nuclear Information System (INIS)

Sage, C.

2009-01-01

Neutron induced reaction cross sections on 241 Am have been measured at the IRMM in Geel, Belgium, in the frame of a collaboration between the EC Joint Research Centres IRMM and ITU and French laboratories from CNRS and CEA. Raw material coming from the Atalante facility of CEA Marcoule has been transformed into suitable AmO 2 samples embedded in Al 2 O 3 and Y 2 O 3 matrices. The irradiations for the 241 Am(n, 2n) 240 Am reaction cross section measurement were carried out at the 7 MV Van de Graaff accelerator using the activation technique with quasi mono-energetic neutrons from 8 to 21 MeV produced via the D(d, n) 3 He and the T(d, n) 4 He reactions. The cross section was determined relative to the 27 Al(n, α) 24 Na standard cross section and was investigated for the first time above 15 MeV. The induced activity was measured off-line by standard γ-ray spectrometry using a high purity Ge detector. A special effort was made for the estimation of the uncertainties and the correlations between our experimental points. A different sample of the same isotope 241 Am has been measured in transmission and capture experiments in the resolved resonance region at the neutron ToF facility GELINA. The transmission measurement was performed in two campaigns, with an upgrade of the whole data acquisition system in between, followed by an investigation of its new performances. A preliminary analysis of the resonance parameters tends to confirm the recent evaluation to a higher value for the cross section at the bottom of the first resonances. A new design of C 6 D 6 detectors for capture measurements has been studied, but the data reduction and analysis of the measurement are not part of this work. (author) [fr

Dedekind σ-complete vector lattice of b-AM-compact operators ...

African Journals Online (AJOL)

We give several equivalent conditions characterizing the case when Krb-AM(E,F) is Dedekind σ-complete. Moreover, we describe the case when the space of all regular b-AM-compact operators from E to F is complete under the b-AM-norm. Keywords: Banach lattices, b-AM-compact operator, discrete space ...

Annotation Method (AM): SE7_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available base search. Peaks with no hit to these databases are then selected to secondary se...arch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are ma...SE7_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary data

Annotation Method (AM): SE36_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE36_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE14_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE14_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE33_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE33_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE12_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE12_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE20_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE20_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE2_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available base search. Peaks with no hit to these databases are then selected to secondary se...arch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are ma...SE2_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary data

Annotation Method (AM): SE28_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE28_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE11_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE11_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE17_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE17_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE10_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE10_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE4_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available base search. Peaks with no hit to these databases are then selected to secondary se...arch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are ma...SE4_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary data

Annotation Method (AM): SE9_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available base search. Peaks with no hit to these databases are then selected to secondary se...arch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are ma...SE9_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary data

Annotation Method (AM): SE3_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available base search. Peaks with no hit to these databases are then selected to secondary se...arch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are ma...SE3_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary data

Annotation Method (AM): SE25_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE25_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE30_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE30_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE16_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE16_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE29_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE29_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE35_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE35_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE6_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available base search. Peaks with no hit to these databases are then selected to secondary se...arch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are ma...SE6_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary data

Annotation Method (AM): SE1_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available base search. Peaks with no hit to these databases are then selected to secondary se...arch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are ma...SE1_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary data

Annotation Method (AM): SE8_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available base search. Peaks with no hit to these databases are then selected to secondary se...arch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are ma...SE8_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary data

Annotation Method (AM): SE13_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE13_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE26_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE26_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE27_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE27_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE34_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE34_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE5_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available base search. Peaks with no hit to these databases are then selected to secondary se...arch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are ma...SE5_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary data

Annotation Method (AM): SE15_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE15_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE31_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE31_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Annotation Method (AM): SE32_AM1 [Metabolonote[Archive

Lifescience Database Archive (English)

Full Text Available abase search. Peaks with no hit to these databases are then selected to secondary s...earch using exactMassDB and Pep1000 databases. After the database search processes, each database hits are m...SE32_AM1 PowerGet annotation A1 In annotation process, KEGG, KNApSAcK and LipidMAPS are used for primary dat

Operational status of the JAEA-Mutsu tandetron AMS

International Nuclear Information System (INIS)

Kabuto, Shoji; Kinoshita, Naoki; Amano, Hikaru; Watanabe, Yukiya; Baba, Masami

2008-01-01

A Tandetron AMS (Accelerator Mass Spectrometer) had been set up at the Japan Atomic Energy Agency (formerly the Japan Atomic Energy Research Institute), Mutsu in 1997. The AMS features 3MV Tandetron accelerator and two independent beamlines for 14 C and 129 I measurement. In this paper, we describe the current status and troubles for the Tandetron AMS with the showing of examples from the last year. (author)

A decade of AMS at University of Georgia

Energy Technology Data Exchange (ETDEWEB)

Culp, Randy, E-mail: rculp@uga.edu [Center for Applied Isotope Studies, University of Georgia, Athens, GA (United States); Noakes, John; Cherkinsky, Alex; Ravi Prasad, G.V.; Dvoracek, Doug [Center for Applied Isotope Studies, University of Georgia, Athens, GA (United States)

2013-01-15

In a span of 10 years, University of Georgia's Center for Applied Isotope Studies (CAIS) has transformed itself from principally a liquid scintillation counting (LSC) laboratory to one conducting thousands of accelerator mass spectrometry (AMS) and stable isotope ratio analysis (SIRA) annually. After receiving the first of the NEC compact AMS units in the United States, the CAIS began to meet the demand for {sup 14}C analysis outside the normal realm of most radiocarbon dating laboratories. With industry's support, isotope research continued on an already developing natural products program to authenticate materials origin and process of formation. The CAIS's AMS allowed for the detection of synthetic materials in milligram quantities rather than gram quantities required by LSC and allowed new compound specific SIRA techniques to be directed toward compound specific {sup 14}C measurement. By 2005 the CAIS was one of only a few laboratories accredited to determine bio-base content in industrial fuels and products by both AMS and LSC following ASTM D6866-10 [1]. Since 2001, when our first sample was analyzed by AMS method, both radiocarbon and natural products sample numbers have increased steadily. The advantages of AMS analysis in overall efficiency, cost savings, accuracy, and precision, are detailed here in a review of analytical precision for radiocarbon and natural products analyzed over 10 years of AMS operation. Comparisons are made between natural products and bio-based materials analyzed by both AMS and LSC. Although high precision is not required to authenticate natural products, for the purpose of product comparison with regard to degree of naturalness accurate and precise {sup 14}C measurement is shown to be achievable by both methods.

[Effects of mycorrhizal colonization and medicine quality of Paris polyphylla var. yunnanensis inoculated by different foreign AM fungi species].

Science.gov (United States)

Zhou Nong; Ding, Bo; Feng, Yuan; Qi, Wen-hua; Zhang, Hua; Guo, Dong-qin; Xiang, Jun

2015-08-01

After 28 foreign species of AM fungi were inoculated in sterilized soil, the effects of the AM mycorrhizal colonization and the medicine quality of Paris polyphylla var. yunnanensis were observed by combination of inoculation test in pot at room temperature and instrumental analysis. The results showed that, compared with control group (CK), the inoculation of foreign AM fungi in the soil influenced the spore density, mycorrhizal infection rate, and colonization intensity of AM fungi in root system of P. polyphylla var. yunnanensis. The inoculation of foreign AM fungi enhanced the mycorrhiza viability of P. polyphylla var. yunnanensis by increasing the activity of succinic dehydrogenase (SDH) and alkaline phosphatase (ALP) in intraradical hyphae. The content of single steroid saponin in rhizome of P. polyphylla var. yunnanensis showed variation after P. polyphylla var. yunnanensis was inoculated by different foreign species of AM fungi, which was beneficial for increasing the medicine quality; however, the kinds of steroid saponin showed no difference. In a degree, there was a selectivity of symbiosis between P. polyphylla var. yunnanensis and foreign AM fungi. And we found that the Claroideoglomus claroideum and Racocetra coralloidea were best foreign AM fungi species for cultivating P. polyphylla var. yunnanensis under field condition.

Aspartic acid complexation of Am(III) and U(VI)

International Nuclear Information System (INIS)

Saito, A.; Choppin, G.R.

1984-01-01

Stability constants of Am(III) and U(VI) with L-aspartic acid have been determined at pH 8.00 by means of the solvent extraction technique. It was found that Am(III) forms 1:1 and 1:2 complexes while U(VI) formed only the 1:1 complex under these conditions. The stability constants were: Am +3 : I = 0.10 M; log β 1 = 4.81 +- 0.03, log β 2 = 6.75 +- 0.03 I = 0.70 M; log β 1 = 4.53 +- 0.08 log β 2 = 6.65 +- 0.06 UO +2 2 : I = 0.70 M; log β 1 = 3.32 +- 0.04. Comparison of these stability constants with corresponding values of some dicarboxylate ligands suggests that at pH 8 the binding of Am +3 and UO +2 2 involves both carboxylates. In the Am-aspartate complex, the data indicate the possibility of weak interaction between the Am +3 and the amino group. (orig.)

Indirect and inclusive search for dark matter with AMS02 space spectrometer

International Nuclear Information System (INIS)

Brun, Pierre

2007-01-01

AMS02 is a particle physics detector designed for 3 years of data taking aboard the International Space Station. Equipped with a superconducting magnet, it will allow to measure gamma and cosmic ray fluxes in the GeV to TeV region with high particle identification capabilities. Its performance is based on the redundancy of measurements in specific sub-detectors: a Time-Of-Flight counter, a Transition Radiation Detector, a Silicon Tracker, a Ring Imaging Cherenkov counter and an Electromagnetic calorimeter (Ecal). The Ecal is studied in details, in particular with the qualification of a stand-alone trigger devoted to gamma ray astronomy. This system allows to increase the AMS02 sensitivity to photons, and to improve the reconstruction of electromagnetic events. The analog part of the trigger system has been tested with test benches and in-beam at CERN. The in-orbit calibration of the Ecal is studied, it may proceed in two steps. First, the Ecal cells responses have to be equalized with minimum ionizing particles data. Then an absolute calibration can be performed with cosmic electrons. For both the relative and the absolute calibration, possible procedures are defined and realistic calibration times are estimated. The second part deals with the indirect searches for dark matter and the study of the AMS02 sensitivity. Dark matter stands for 84% of the Universe mass and could consist in new particles. Dark matter particles are expected to surround our Galaxy and annihilate in high density regions. These annihilations could become observable exotic primary cosmic ray sources. Searches for anomalous excesses in (p-bar, e + , D-bar) and γ ray fluxes will be performed by AMS02. A numerical tool allowing to perform predictions for these exotic fluxes within supersymmetry or extra-dimension is developed and is presented in details. Phenomenological studies regarding possible enhancements of these signals by over-dense regions of the halo have also been performed. The

Temelin 1000 MW Units active testing stage - commissioning experience

International Nuclear Information System (INIS)

Ubra, O.; Riha, V.

2003-01-01

There were three basic stages of the NPP Temelin Units active testing stage- The zero and low power testing, The power ascension testing and Plant Performance Test. The main objective of the start- up process stages and the testing procedures including some operational experience are described in the paper. (author)

Status report on sample preparation facilities for {sup 14}C analysis at the new CologneAMS center

Energy Technology Data Exchange (ETDEWEB)

Rethemeyer, J., E-mail: janet.rethemeyer@uni-koeln.de [Institute of Geology and Mineralogy, University of Cologne, 50674 Cologne (Germany); Fueloep, R.-H.; Hoefle, S. [Institute of Geology and Mineralogy, University of Cologne, 50674 Cologne (Germany); Wacker, L. [Ion Beam Physics, ETH Zuerich, 8093 Zuerich (Switzerland); Heinze, S. [Institute of Nuclear Physics, University of Cologne, 50674 Cologne (Germany); Hajdas, I. [Ion Beam Physics, ETH Zuerich, 8093 Zuerich (Switzerland); Patt, U.; Koenig, S.; Stapper, B. [Institute of Geology and Mineralogy, University of Cologne, 50674 Cologne (Germany); Dewald, A. [Institute of Nuclear Physics, University of Cologne, 50674 Cologne (Germany)

2013-01-15

The new AMS facility at University of Cologne (CologneAMS), Germany, was established in 2010 with the delivery of the HVE 6 MV Tandetron AMS, which will be used for {sup 14}C, {sup 26}Al, {sup 36}Cl, {sup 41}Ca, {sup 129}I, {sup 239}U and {sup 244}Pu analyses. Parallel to the AMS installation the radiocarbon group has started to set up and test sample preparation methods and instruments for different materials. We present first results of reference and standard materials that have been processed and graphitized in our lab and measured at the ETH and CologneAMS facilities. The graphitization blank and its influence on small samples sizes processed with an automated graphitization system have been determined. Work on isolation of individual organic compounds with a preparative gas chromatography system has been started. The focus of our future work will be on reducing process blank levels and sample sizes as well as on the application of compound-specific radiocarbon analyses in (paleo-) environmental research.

"I Am Not a Format": Teachers' Experiences with Fostering Creativity in the Era of Accountability

Science.gov (United States)

Olivant, Katie F.

2015-01-01

This phenomenological study examined the experience of fostering creativity and creative thinking in the classroom under high-stakes testing conditions, as described by teachers at a magnet elementary school in Central California. The tensions between standardization and professionalism, as well as performativity and creativity, served as the…

A Research of RSSI-AM Localization Algorithm Based on Data Encryption in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Wang Wei

2014-07-01

Full Text Available In practical application of wireless sensor networks, because of open environment, signal is easy to be attacked and traditional RSSI location technology produces errors. By analyzing the location modal of RSSI, this paper proposes a new encryption modulation algorithm: RSSI-AM, which is unlike most approaches. The location algorithm has the following advantages: simple calculation, strong security, powerful anti-interference ability and no hardware expansion required. Besides, the simulation experiment shows the location precision of ranging method based on RSSI-AM has obvious improvement compared with traditional algorithm. It can be used in the environment of wireless sensor network nodes with low cost and performance of hardware.

A PMT mass testing facility for the JUNO experiment

Energy Technology Data Exchange (ETDEWEB)

Tietzsch, Alexander; Alsheimer, Isabell; Blum, David; Lachenmaier, Tobias; Sterr, Tobias [Physikalisches Institut, Universitaet Tuebingen (Germany); Bein, Bosse; Bick, Daniel; Ebert, Joachim; Hagner, Caren; Rebber, Henning; Steppat, Lisa; Wonsak, Bjoern [Institut fuer Experimentalphysik, Universitaet Hamburg (Germany)

2016-07-01

The JUNO (Jiangmen Underground Neutrino Observatory) experiment will be one of the big neutrino oscillation experiments starting in the next years. The main goal of JUNO is the determination of the neutrino mass hierarchy. To detect the sub-dominant effects in the oscillation pattern which depend on the mass hierarchy, the JUNO detector is planned with almost 20 kt fiducial volume, high light yield and energy resolution of better than 3%. In order to reach this, roughly 17000 newly developed high QE PMTs for the central detector, and additionally 2000 for the veto will be used. Each PMT has to be tested and characterized before it will be mounted in the experiment. This talk gives an overview on our plans and strategy for the mass test of all PMTs, and on the current status of the experimental test setup and next steps. The testing facility is developed in a cooperation between the Physical Institutes in Tuebingen and Hamburg within the JUNO collaboration.

Vertical profiles of 239(240)Pu, 238Pu and 241Am in some peculiar Italian mosses

International Nuclear Information System (INIS)

Testa, C.; Desideri, D.; Guerra, F.; Meli, M.A.; Roselli, C.; Jia, G.; Degetto, S.

2000-01-01

During the last two years the Urbino University and the Padua ICTIMA CNR were working on a special radioecological program having the aim to study the Pu and Am retention behaviour in different species of mosses growing in two Italian regions (Urbino, Central Italy, 450 m a.s.l. and Alps region, Northern Italy, 1500 m a.s.l.). 239,240 Pu, 238 Pu and 241 Am were separated and determined by extraction chromatography, electroplating and alpha spectrometry; 242 Pu and 243 Am were used as the yield tracers. The paper summarizes the results dealing with the vertical profiles of the radionuclides in three different species of mosses. Several 1-2 cm high sections were obtained and dated by 210 Pb determination. Typical concentration peaks for Pu and Am were found for very old moss species ('Sphagnum Compactum' and 'Sphagnum Nemoreum') at a depth corresponding to the early 1960's which is the period characterized by the maximum nuclear weapon tests. In more recent moss species ('Neckeria Crispa') no peak was observed and the regression curves showed that Am is more mobile than Pu. (author)

Experiments on the Synthesis of Element 115 in the Reaction ^{243}Am (^{48}Ca, xn)^{291-x}115

CERN Document Server

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

2003-01-01

The results of experiments designed to synthesize element 115 isotopes in the ^{243}Am(^{48}Ca,xn)^{291-x}115 reaction are presented. With a beam dose of 4.3\\cdot 10^{18} 248-Mev ^{48}Ca projectiles, we observed three similar decay chains consisting of five consecutive alpha-decays, all detected in time intervals of about 20 s and terminated at a later time by a spontaneous fission with a high energy release (TKE \\sim 220 MeV). At a higher bombarding energy of 253 MeV, with an equal ^{48}Ca beam dose, we registered a different decay chain of four consecutive alpha-decays detected in a time interval of about 0.5 s, also terminated by spontaneous fission. The alpha-decay energies and half-lives for nine new alpha-decaying nuclei were determined. The decay properties of these synthesized nuclei are consistent with consecutive alpha-decays originating from the parent isotopes of the new element 115, ^{288}115 and ^{287}115, produced in the 3n- and 4n-evaporation channels with cross sections of about 3 and 1 pb, r...

Test facility for rewetting experiments at CDTN

International Nuclear Information System (INIS)

Rezende, Hugo C.; Mesquita, Amir Z.; Ladeira, Luiz C.D.; Santos, Andre A.C.

2015-01-01

One of the most important subjects in nuclear reactor safety analysis is the reactor core rewetting after a Loss-of-Coolant Accident (LOCA) in a Light Water Reactor LWR. Several codes for the prediction of the rewetting evolution are under development based on experimental results. In a Pressurized Water Reactor (PWR) the reflooding phase of a LOCA is when the fuel rods are rewetted from the bottom of the core to its top after having been totally uncovered and dried out. Out-of-pile reflooding experiments performed with electrical heated fuel rod simulators show different quench behavior depending the rods geometry. A test facility for rewetting experiments (ITR - Instalacao de Testes de Remolhamento) has been constructed at the Thermal Hydraulics Laboratory of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), with the objective of performing investigations on basic phenomena that occur during the reflood phase of a LOCA in a PWR, using tubular and annular test sections. This paper presents the design aspects of the facility, and the current stage of the works. The mechanical aspects of the installation as its instrumentation are described. Two typical tests are presented and results compered with theoretical calculations using computer code. (author)

Test facility for rewetting experiments at CDTN

Energy Technology Data Exchange (ETDEWEB)

Rezende, Hugo C.; Mesquita, Amir Z.; Ladeira, Luiz C.D.; Santos, Andre A.C., E-mail: hcr@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (SETRE/CDTN/CNEN-MG), Belo Horizonte, MG (Brazil). Servico de Tecnologia de Reatores

2015-07-01

One of the most important subjects in nuclear reactor safety analysis is the reactor core rewetting after a Loss-of-Coolant Accident (LOCA) in a Light Water Reactor LWR. Several codes for the prediction of the rewetting evolution are under development based on experimental results. In a Pressurized Water Reactor (PWR) the reflooding phase of a LOCA is when the fuel rods are rewetted from the bottom of the core to its top after having been totally uncovered and dried out. Out-of-pile reflooding experiments performed with electrical heated fuel rod simulators show different quench behavior depending the rods geometry. A test facility for rewetting experiments (ITR - Instalacao de Testes de Remolhamento) has been constructed at the Thermal Hydraulics Laboratory of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), with the objective of performing investigations on basic phenomena that occur during the reflood phase of a LOCA in a PWR, using tubular and annular test sections. This paper presents the design aspects of the facility, and the current stage of the works. The mechanical aspects of the installation as its instrumentation are described. Two typical tests are presented and results compered with theoretical calculations using computer code. (author)

Decommissioning strategy for reactor AM, Russian Federation

International Nuclear Information System (INIS)

Suvorov, A.P.; Mukhamadeev, R.I.

2002-01-01

This paper presents the results of studies into the various aspects of decommissioning the oldest Russian research reactor, the AM reactor. Experimental and calculation results of a study to determine the inventory of long lived radioactive materials at the AM reactor are presented, along with a comparison to comparable data for other similar reactors. An analysis, by calculation, of the decay time needed to allow manual dismantling of the reactor vessel and stack, without remote operated equipment, defined it as 90 years. The possibility of burning most of the irradiated graphite to decrease the amount of long lived radioactive wastes was confirmed. The problems associated with the dismantling of the reactor components, contaminated with radioactive corrosion products, were analyzed. A decommissioning strategy for reactor AM was formed which is deferred dismantling, placing most of the radiological areas into long term safe enclosure. An overall decommissioning plan for reactor AM is given. (author)

Data report of ROSA/LSTF experiment SB-CL-32. 1% cold leg break LOCA with SG depressurization and no gas inflow

International Nuclear Information System (INIS)

Takeda, Takeshi

2014-11-01

An experiment SB-CL-32 was conducted on May 28, 1996 using the Large Scale Test Facility (LSTF) in the Rig of Safety Assessment-V (ROSA-V) Program. The ROSA/LSTF experiment SB-CL-32 simulated a 1% cold leg small-break loss-of-coolant accident in a pressurized water reactor under assumptions of total failure of high pressure injection system and no inflow of non-condensable gas from accumulator (ACC) tanks of emergency core cooling system. Secondary-side depressurization of both steam generators (SGs) as an accident management (AM) action to achieve the depressurization rate of 200 K/h in the primary system was initiated 10 min after the break. After the initiation of AM action, auxiliary feedwater injection into the SG secondary-side was started with some delay. After the onset of AM action, the primary pressure decreased following the SG secondary-side pressure. Core uncovery by core boil-off started with liquid level drop in crossover leg downflow-side. The core liquid level recovered rapidly after first loop seal clearing (LSC). The surface temperature of simulated fuel rod then increased up to 669 K. Core uncovery by core boil-off took place before second LSC induced by steam condensation on ACC coolant injected into cold legs following the primary depressurization. The core liquid level recovered rapidly after the second LSC. The observed maximum fuel rod surface temperature was 772 K. The experiment was terminated when the continuous core cooling was confirmed because of the coolant injection by low pressure injection system after the isolation of ACC system. The obtained data would be useful to define the conditions for counterpart testing of other integral test facilities to address scaling problems through thermal-hydraulic phenomena. This report summarizes the test procedures, conditions and major observation in the ROSA/LSTF experiment SB-CL-32. (author)

241Am distribution and retention in pregnant mice, in their offspring and in non-pregnant mice: comparison between continuous Am administration and single injection

International Nuclear Information System (INIS)

Huevel, R. Van Den; Vander Plaetse, F.; Leppens, H.; Schoeters, G.

1992-01-01

Pregnant BALB/c mice and age and sex matched nulliparous controls were contaminated with 241 Am (13 kBq per mouse). Five days after the termination of contamination, 241 Am incorporation was measured in the tissues of adults and in the liver an the femur of newborn and one-month-old mice. Pregnancy resulted in higher 241 Am concentrations in bone but lower concentrations in the liver of the mothers. Protracted administration of 241 Am compared to a single injection resulted in a lower concentration of 241 Am in the livers of pregnant mice, their nulliparous controls and from newborn mice. The higher 241 Am concentration in the femur at birth after protected exposure before 14 days of gestation compared to protracted exposure after 14 days of gestation could reflect the increased placental transfer of 241 Am with advancing gestational age. Radiation doses to the femur were estimated between 4 and 20 mGy. Haemopoietic changes were noticed at these dose levels in all groups until at least 6 months after birth. (author)

Blob accretion in AM Herculis systems

International Nuclear Information System (INIS)

Litchfield, S.J.; King, A.R.

1990-01-01

We calculate self-consistent hydrostatic temperature distributions for the atmosphere of a white dwarf in an AM Herculis system on to which a discrete blob has accreted. We show that the surface derived from this temperature structure does not produce soft X-ray light curves characteristic of the anomalous X-ray state of AM Herculis. We suggest that non-hydrostatic splashes are a more likely origin for the light curves. (author)

An interspecies comparison of the phagocytosis and dissolution of 241AmO2 particles by rat, dog and monkey alveolar macrophages in vitro

International Nuclear Information System (INIS)

Taya, A.; Carmack, D.B.; Muggenburg, B.A.; Mewhinney, J.A.

1992-01-01

Experiments were conducted to study the phagocytosis and dissolution of 241 AmO 2 particles by rat, dog and monkey alveolar macrophages (PAM) in vitro. The phagocytosis and dissolution of 241 AmO 2 particles were followed up to 20 and 72 h, respectively. Dog and monkey PAM took up 241 AmO 2 particles at similar rates, whereas rat PAM phagocytosed only 60% of the amount phagocytosed by dog and monkey PAM at 20h. The PAM of the three species dissolved 241 AmO 2 particles at similar rates; 8-10% was dissolved by 72h. The results of the 241 AmO 2 uptake in vitro may reflect in vivo situations, where the differences in uptake seen in vitro would probably diminish at later times after exposure. The dissolution results imply that the dissolution of 241 AmO 2 particles by alveolar macrophages of the three species might be species-independent. (author)

Retention and distribution of 241AmIII in neonatal beagles

International Nuclear Information System (INIS)

Stevens, W.; Atherton, D.R.; Bates, D.; Lloyd, R.D.; Buster, D.S.; Bruenger, F.W.

1977-01-01

The distribution of Am in newborn beagles was studied during the first week after birth. Seven litter mates (4 males, 3 females) weighing 250-280 g were injected intravenously with 3.0 μCi 241 AmIII/kg, in citrate buffer, at 1 day of age and sacrificed 1, 3 and 5 days later. At sacrifice, livers, spleens, kidneys, other selected soft tissues and skeletons were analyzed for Am content. Cumulative excretion during the time observed was 6.7% of the injected dose, 5.5% of which occurred during the first day. Skeletal retention ranged from 76% of the injected dose at 1 day to 84% by 5 days. The skeletons of dogs given the same dose of Am at 18 months of age contained 29% of the injected Am at 1 week. The relative distribution of Am within the skeleton was dependent on the state of development of its individual bones and differed considerably from that of the young adult. In neonates, the Am content of the bones of the skull was 3 times that seen in dogs injected as young adults. Initial liver deposition of Am in neonates was only 7%, in contrast to approximately 50% in young adult beagles. The subcellular distribution of Am in liver also differed in the two age groups. In neonates, a greater fraction of the nuclide was associated with soluble proteins of the cytosol, and the increase in the Am content of mitochondria and lysosomes proceeded at a much slower rate than was observed in mature animals. (author)

Similarity of /sup 241/Am and /sup 59/Fe speciation in selected freshwaters and of their adsorption on crayfish exoskeleton

Energy Technology Data Exchange (ETDEWEB)

Vangenechten, J.H.D.; Chughtai, N.A.; Bierkens, J.; Vanderborght, O.L.J.

1987-01-01

The particulate fraction and the organically complexed fraction of freshly added /sup 241/Am and /sup 59/Fe were determined in 21 prefiltered surface waters. The adsorptive behaviour of both radionuclides on a biological surface (isolated carapace segments of crayfish) was tested simultaneously. A striking similarity was observed in the chemical and absorptive behaviours of both radionuclides. The stoichiometry of particulate formation revealed a 3/4, Am to Fe ratio. This same stoichiometric relationship was observed in organic complexation, while adsorptive behaviour was characterised by a 1/1, Am to Fe ratio. It is concluded that Am predictably follows the chemistry of freshly added Fe at least over a 15 day period. This observation may find interesting application in risk assessment where use can be made of the well-known geochemical cycling of iron to predict the behaviour of man-made Am.

Lace plant ethylene receptors, AmERS1a and AmERS1c, regulate ethylene-induced programmed cell death during leaf morphogenesis.

Science.gov (United States)

Rantong, Gaolathe; Evans, Rodger; Gunawardena, Arunika H L A N

2015-10-01

The lace plant, Aponogeton madagascariensis, is an aquatic monocot that forms perforations in its leaves as part of normal leaf development. Perforation formation occurs through developmentally regulated programmed cell death (PCD). The molecular basis of PCD regulation in the lace plant is unknown, however ethylene has been shown to play a significant role. In this study, we examined the role of ethylene receptors during perforation formation. We isolated three lace plant ethylene receptors AmERS1a, AmERS1b and AmERS1c. Using quantitative PCR, we examined their transcript levels at seven stages of leaf development. Through laser-capture microscopy, transcript levels were also determined in cells undergoing PCD and cells not undergoing PCD (NPCD cells). AmERS1a transcript levels were significantly lower in window stage leaves (in which perforation formation and PCD are occurring) as compared to all other leaf developmental stages. AmERS1a and AmERS1c (the most abundant among the three receptors) had the highest transcript levels in mature stage leaves, where PCD is not occurring. Their transcript levels decreased significantly during senescence-associated PCD. AmERS1c had significantly higher transcript levels in NPCD compared to PCD cells. Despite being significantly low in window stage leaves, AmERS1a transcripts were not differentially expressed between PCD and NPCD cells. The results suggested that ethylene receptors negatively regulate ethylene-controlled PCD in the lace plant. A combination of ethylene and receptor levels determines cell fate during perforation formation and leaf senescence. A new model for ethylene emission and receptor expression during lace plant perforation formation and senescence is proposed.

Safety Assurance for Irradiating Experiments in the Advanced Test Reactor

Energy Technology Data Exchange (ETDEWEB)

T. A. Tomberlin; S. B. Grover

2004-11-01

The Advanced Test Reactor (ATR), located at the Idaho National Engineering and Environmental Laboratory (INEEL), was specifically designed to provide a high neutron flux test environment for conducting a variety of experiments. This paper addresses the safety assurance process for two general types of experiments conducted in the ATR facility and how the safety analyses for experiments are related to the ATR safety basis. One type of experiment is more routine and generally represents greater risks; therefore, this type of experiment is addressed in more detail in the ATR safety basis. This allows the individual safety analysis for this type of experiment to be more standardized. The second type of experiment is defined in more general terms in the ATR safety basis and is permitted under more general controls. Therefore, the individual safety analysis for the second type of experiment tends to be more unique and is tailored to each experiment.

Safety Assurance for Irradiating Experiments in the Advanced Test Reactor

International Nuclear Information System (INIS)

T. A. Tomberlin; S. B. Grover

2004-01-01

The Advanced Test Reactor (ATR), located at the Idaho National Engineering and Environmental Laboratory (INEEL), was specifically designed to provide a high neutron flux test environment for conducting a variety of experiments. This paper addresses the safety assurance process for two general types of experiments conducted in the ATR facility and how the safety analyses for experiments are related to the ATR safety basis. One type of experiment is more routine and generally represents greater risks; therefore, this type of experiment is addressed in more detail in the ATR safety basis. This allows the individual safety analysis for this type of experiment to be more standardized. The second type of experiment is defined in more general terms in the ATR safety basis and is permitted under more general controls. Therefore, the individual safety analysis for the second type of experiment tends to be more unique and is tailored to each experiment

Dark matter vs. astrophysics in the interpretation of AMS-02 electron and positron data

Energy Technology Data Exchange (ETDEWEB)

Mauro, Mattia Di; Donato, Fiorenza; Fornengo, Nicolao; Vittino, Andrea, E-mail: mattia.dimauro@to.infn.it, E-mail: donato@to.infn.it, E-mail: fornengo@to.infn.it, E-mail: vittino@to.infn.it [Department of Physics, University of Torino, via P. Giuria 1, 10125 Torino (Italy)

2016-05-01

We perform a detailed quantitative analysis of the recent AMS-02 electron and positron data. We investigate the interplay between the emission from primary astrophysical sources, namely Supernova Remnants and Pulsar Wind Nebulae, and the contribution from a dark matter annihilation or decay signal. Our aim is to assess the information that can be derived on dark matter properties when both dark matter and primary astrophysical sources are assumed to jointly contribute to the leptonic observables measured by the AMS-02 experiment. We investigate both the possibility to set robust constraints on the dark matter annihilation/decay rate and the possibility to look for dark matter signals within realistic models that take into account the full complexity of the astrophysical background. Our results show that AMS-02 data enable to probe efficiently vast regions of the dark matter parameter space and, in some cases, to set constraints on the dark matter annihilation/decay rate that are comparable or even stronger than the ones derived from other indirect detection channels.

Dark matter vs. astrophysics in the interpretation of AMS-02 electron and positron data

International Nuclear Information System (INIS)

Mauro, Mattia Di; Donato, Fiorenza; Fornengo, Nicolao; Vittino, Andrea

2016-01-01

We perform a detailed quantitative analysis of the recent AMS-02 electron and positron data. We investigate the interplay between the emission from primary astrophysical sources, namely Supernova Remnants and Pulsar Wind Nebulae, and the contribution from a dark matter annihilation or decay signal. Our aim is to assess the information that can be derived on dark matter properties when both dark matter and primary astrophysical sources are assumed to jointly contribute to the leptonic observables measured by the AMS-02 experiment. We investigate both the possibility to set robust constraints on the dark matter annihilation/decay rate and the possibility to look for dark matter signals within realistic models that take into account the full complexity of the astrophysical background. Our results show that AMS-02 data enable to probe efficiently vast regions of the dark matter parameter space and, in some cases, to set constraints on the dark matter annihilation/decay rate that are comparable or even stronger than the ones derived from other indirect detection channels.

Performance of the AMS-02 Transition Radiation Detector

CERN Document Server

von Doetinchem, P.; Karpinski, W.; Kirn, T.; Luebelsmeyer, K.; Orboeck, J.; Schael, S.; Schultz von Dratzig, A.; Schwering, G.; Siedenburg, T.; Siedling, R.; Wallraff, W.; Becker, U.; Burger, J.; Henning, R.; Kounine, A.; Koutsenko, V.; Wyatt, J.

2006-01-01

For cosmic particle spectroscopy on the International Space Station the AMS experiment will be equipped with a Transition Radiation Detector (TRD) to improve particle identification. The TRD has 20 layers of fleece radiator with Xe/CO2 proportional mode straw tube chambers. They are supported in a conically shaped octagon structure made of CFC-Al-honeycomb. For low power consumption VA analog multiplexers are used as front-end readout. A 20 layer prototype built from final design components has achieved proton rejections from 100 to 2000 at 90% electron efficiency for proton beam energies up to 250 GeV with cluster counting, likelihood and neural net selection algorithms.

Testing the AVNG

International Nuclear Information System (INIS)

Thron, Jonathan Louis; MacArthur, Duncan W.; Kondratov, Sergey; Livke, Alexander; Razinkov, Sergey

2010-01-01

An attribute measurement system (AMS) measures a number of unclassified attributes of potentially classified material. By only displaying these unclassified results as red or green lights, the AMS protects potentially classified information while still generating confidence in the measurement result. The A VNG implementation that we describe is an AMS built by RFNC - VNIIEF in Sarov, Russia. The AVNG detects neutron and gamma radiation signatures and displays the three unclassified attributes of 'plutonium presence,' 'plutonium mass > 2 kg,' and 'plutonium isotopic ratio ( 240 Pu to 239 Pu) < 0.1.' Prior to demonstration to a joint US/Russian audience, the overall operation and thresholds of the AVNG were tested using a number of multi-kg plutonium reference material (RM) sources manufactured for this purpose. As the AVNG was designed to incorporate an open mode (where all radiation data was displayed) as well as a secure mode (where only the red/green attribute lights were visible), the AVNG was tested in both modes. We will present data from these tests using unclassified plutonium RM sources as well as detector test results obtained using smaller calibration sources.

Generalized requirements and decompositions for the design of test parts for micro additive manufacturing research

DEFF Research Database (Denmark)

Thompson, Mary Kathryn; Clemmensen, Line Katrine Harder

2015-01-01

The design of experimental test parts to characterize micro additive manufacturing (AM) processes is challenging due to the influence of the manufacturing and metrology processes. This work builds on the lessons learned from a case study in the literature to derive generalized requirements and high...... level decompositions for the design of test parts and the design of experiments to characterize micro additive manufacturing processes. While the test parts and the experiments described are still work in progress, the generic requirements derived from them can serve as a starting point for the design...... of other micro additive manufacturing related studies and their decompositions can help structure future work....

Imaging AMS

Energy Technology Data Exchange (ETDEWEB)

Freeman, S.P.H.T. [Univ. of Oxford (United Kingdom)]|[Lawrence Livermore National Lab., CA (United States); Ramsey, C.B.; Hedges, R.E.M. [Univ. of Oxford (United Kingdom)

1993-12-01

The benefits of simultaneous high effective mass resolution and large spectrometer acceptance that accelerator mass spectrometry has afforded the bulk analysis of material samples by secondary ion mass spectrometry may also be applied to imaging SIMS. The authors are exploring imaging AMS with the addition to the Oxford {sup 14}C-AMS system of a scanning secondary ion source. It employs a sub micron probe and a separate Cs flood to further increase the useful ion yield. The source has been accommodated on the system by directly injecting sputtered ions into the accelerator without mass analysis. They are detected with a range of devices including new high-bandwidth detectors. Qualitative mass spectra may be easily generated by varying only the post-accelerator analysis magnet. Selected ion signals may be used for imaging. In developing the instrument for bioscience research the authors are establishing its capability for measuring the lighter elements prevalent in biological tissue. Importantly, the machine can map the distributions of radiocarbon labeled compounds with an efficiency of about 1{per_thousand}. A background due to misidentification of non-{sup 14}C ions as a result of the reduced ion mass filtering is too small to hinder high magnification microscopy.

Think Big: Leadership Projects for AMS and Montessori Educators

Science.gov (United States)

Chattin-McNichols, John

2014-01-01

The American Montessori Society's (AMS) 2014 Living Legacy recipient, John Chattin-McNichols, delivered the keynote address at the Annual Conference in Dallas, TX, on March 27, 2014, In his speech, he described three overall highlights of AMS: (1) AMS is now a world-leading organization; (2) It must become a learning organization; and (3)…

AMS at the National Institute of Nuclear Physics and Engineering in Bucharest

International Nuclear Information System (INIS)

Stan-Sion, C.; Ivascu, M.; Plostinaru, D.; Catana, D.; Marinescu, L.; Radulescu, M.; Nolte, E.

2000-01-01

A new beam line and injector deck for AMS measurements have been built at the 8 MV tandem accelerator of the National Institute of Nuclear Physics and Engineering, Bucharest, Romania. The main components on the low-energy side are a high-current cesium sputter source, a 90 deg. injection magnet and a pre-acceleration stage. At the high-energy side the beam line is achromatic, consisting of two 90 deg. analysing magnets with mass energy product 120 MeV amu and a gas-filled ionization chamber. The system will be complete with a Wien filter and a multi-anode gas detector with time-of-flight discrimination. Presently, the AMS facility is undergoing tests and routine measurements are expected to start soon

AMS at the National Institute of Nuclear Physics and Engineering in Bucharest

Energy Technology Data Exchange (ETDEWEB)

Stan-Sion, C. E-mail: stansion@ifin.nipne.ro; Ivascu, M.; Plostinaru, D.; Catana, D.; Marinescu, L.; Radulescu, M.; Nolte, E

2000-10-01

A new beam line and injector deck for AMS measurements have been built at the 8 MV tandem accelerator of the National Institute of Nuclear Physics and Engineering, Bucharest, Romania. The main components on the low-energy side are a high-current cesium sputter source, a 90 deg. injection magnet and a pre-acceleration stage. At the high-energy side the beam line is achromatic, consisting of two 90 deg. analysing magnets with mass energy product 120 MeV amu and a gas-filled ionization chamber. The system will be complete with a Wien filter and a multi-anode gas detector with time-of-flight discrimination. Presently, the AMS facility is undergoing tests and routine measurements are expected to start soon.

A new AMS facility based on a Cockcroft-Walton type 1 MV tandetron at IFIN-HH Magurele, Romania

Science.gov (United States)

Stan-Sion, C.; Enachescu, M.; Ghita, D. G.; Calinescu, C. I.; Petre, A.; Mosu, D. V.; Klein, M.

2014-01-01

A 1 MV AMS machine was recently installed in the National Institute for Physics and Nuclear Engineering IFIN-HH, Bucharest Romania. It is the second AMS facility at IFIN-HH having the goal not only to continue but mainly to enlarge the research area of this highly sensitive analyzing method. The multi-element AMS was developed by HVEE to measure 14C, 10Be, and 26Al, and 129I. The results of an acceptance test are presented and demonstrate that this machine is capable of routine 14C age dating and of measurements of other radioisotopes in terms of accuracy and precision as well as a low background level.

Report of the IAEA A+M Data Unit. Appendix 4

Energy Technology Data Exchange (ETDEWEB)

Lorenz, A. [International Atomic Energy Agency, Nuclear Data Section, Vienna (Austria)

1984-11-15

At the present time, the Agency's A+M programme consists of the following principal activities: - assessment of data needs and research coordination and support, - development of the A+M EXFOR for the storage and exchange of data, and the establishment of a numerical A+M data base, and - continuous compilation of bibliographic reference data into the A+M/BDB (Bibliographic Data Base), and the publication of the A+M Data Bulletin.

Does the Fizeau Experiment Really Test Special Relativity?

Science.gov (United States)

Clement, Gerard

1980-01-01

The motivation and interpretation of the Fizeau experiment are reviewed, and its status as a test of special relativity is discussed. It is shown, with the aid of a simplified, purely mechanical model of the propagation of light in matter, that the experiment actually cannot discriminate between Galilean and relativistic kinematics. (Author/SK)

Automatically generated acceptance test: A software reliability experiment

Science.gov (United States)

Protzel, Peter W.

1988-01-01

This study presents results of a software reliability experiment investigating the feasibility of a new error detection method. The method can be used as an acceptance test and is solely based on empirical data about the behavior of internal states of a program. The experimental design uses the existing environment of a multi-version experiment previously conducted at the NASA Langley Research Center, in which the launch interceptor problem is used as a model. This allows the controlled experimental investigation of versions with well-known single and multiple faults, and the availability of an oracle permits the determination of the error detection performance of the test. Fault interaction phenomena are observed that have an amplifying effect on the number of error occurrences. Preliminary results indicate that all faults examined so far are detected by the acceptance test. This shows promise for further investigations, and for the employment of this test method on other applications.

Latest AMS Results on elementary particles in cosmic rays

Science.gov (United States)

Kounine, Andrei; AMS Collaboration

2017-01-01

AMS-02 is a particle physics detector collecting data on the International Space Station since May 2011. Precision measurements of all elementary charged cosmic ray particles have been performed by AMS using a data sample of 85 billion cosmic ray events collected during the first five years of operations on the Station. The latest AMS results on the fluxes and flux ratios of the elementary cosmic ray particles are presented. They show unique features that require accurate theoretical interpretation as to their origin, be it from dark matter collisions or new astrophysical sources. On behalf of the AMS Collaboration.

Compilation of MCNP data library based on JENDL-3T and test through analysis of benchmark experiment

International Nuclear Information System (INIS)

Sakurai, K.; Sasamoto, N.; Kosako, K.; Ishikawa, T.; Sato, O.; Oyama, Y.; Narita, H.; Maekawa, H.; Ueki, K.

1989-01-01

Based on an evaluated nuclear data library JENDL-3T, a temporary version of JENDL-3, a pointwise neutron cross section library for MCNP code is compiled which involves 39 nuclides from H-1 to Am-241 which are important for shielding calculations. Compilation is performed with the code system which consists of the nuclear data processing code NJOY-83 and library compilation code MACROS. Validity of the code system and reliability of the library are certified by analysing benchmark experiments. (author)

Behavior of Am in acidic and basic solutions of potassium ferri/ferrocyanide

International Nuclear Information System (INIS)

Kulyako, Yu.M.; Trofimov, T.I.; Malikov, D.A.; Lebedev, I.A.; Myasoedov, B.F.

1994-01-01

The behavior of Am in acidic and basic solutions containing the Fe(CN) 3- 6 /Fe(CN) 4- 6 redox system is studied. In mineral acids, K 3 Fe(CN) 6 and Am(III) form the poorly soluble compound AmFe(CN) 6 , which with time undergoes a change owing to radiolytic reduction of Fe(CN) 3- 6 to Fe(CN) 4- 6 . In basic solutions of K 3 Fe(CN) 6 , Am(III) is oxidized to AmO + 2 , forming the soluble complex (AmO 2 ) 3 Fe(CN) 6 , which gradually decomposes to produce the solid double hydroxide Na 2 AmO 2 (OH) 3 ·nH 2 O. An Am(IV) hydroxide is formed if [Am] and [K 3 Fe(CN) 6 ] are equal

Effect of gavaged chemical form of 241Am on its retention in mice

International Nuclear Information System (INIS)

Hisamatsu, S.; Takizawa, Y.

1987-01-01

The retention of 241 Am in mice 48 h after administration by gavage is reported here. The 241 Am was given to mice in the form of either 241 Am nitrate or 241 Am citrate. The 241 Am was also injected into rats in the same form. The homogenized livers of those rats were subsequently administered by gavage to another group of mice. The retention of 241 Am citrate was 1.5 X 10(-2)% of the original dose and was the highest among the compounds examined. The retention of biologically incorporated 241 Am into the liver as 241 Am nitrate and as 241 Am citrate was 2.4 X 10(-3) and 2.6 X 10(-3)%, respectively, and was similar to the retention of 241 Am nitrate, which was 2.8 X 10(-3)%. The ratio of the retention in the carcass to that in the liver for the 241 Am citrate was lower than that of the 241 Am nitrate and the biologically incorporated 241 Am. This difference indicates that the distribution of 241 Am in the animal body depends on the chemical form administered. The retention of liver-incorporated 241 Am as citrate after autolysis of the liver is similar to that of fresh liver-incorporated 241 Am citrate

Operating experience of steam generator test facility

International Nuclear Information System (INIS)

Sureshkumar, V.A.; Madhusoodhanan, G.; Noushad, I.B.; Ellappan, T.R.; Nashine, B.K.; Sylvia, J.I.; Rajan, K.K.; Kalyanasundaram, P.; Vaidyanathan, G.

2006-01-01

Steam Generator (SG) is the vital component of a Fast Reactor. It houses both water at high pressure and sodium at low pressure separated by a tube wall. Any damage to this barrier initiates sodium water reaction that could badly affect the plant availability. Steam Generator Test Facility (SGTF) has been set up in Indira Gandhi Centre for Atomic Research (IGCAR) to test sodium heated once through steam generator of 19 tubes similar to the PFBR SG dimension and operating conditions. The facility is also planned as a test bed to assess improved designs of the auxiliary equipments used in Fast Breeder Reactors (FBR). The maximum power of the facility is 5.7 MWt. This rating is arrived at based on techno economic consideration. This paper covers the performance of various equipments in the system such as Electro magnetic pumps, Centrifugal sodium pump, in-sodium hydrogen meters, immersion heaters, and instrumentation and control systems. Experience in the system operation, minor modifications, overall safety performance, and highlights of the experiments carried out etc. are also brought out. (author)

Kusheh, na minem Fatu, en mi na koko farmer Hello, I am Fatu and I am a cocoa farmer

NARCIS (Netherlands)

Witteveen, L.M.; Goris, Margriet; Lie, R.; Ingram, V.J.

2016-01-01

This document reports on the development of a prototype Digital Farmer Field School (DFFS) called Kusheh, na minem Fatu, en mi na koko farmer (“Hello, I am Fatu and I am a cocoa farmer”). The DFFS provides an ICT-based alternative to traditional agricultural extension. More specifically, it offers a

Removal of inhaled 241Am oxide particles from beagle dogs by combined treatment with lung lavage and a chelating agent

International Nuclear Information System (INIS)

Muggenburg, B.A.; Mewhinney, J.A.; Mo, T.; Slauson, D.O.

1978-01-01

This experiment was performed to evaluate combined therapy of lung lavage and chelation treatments to remove inhaled particles of 241 Am oxide. Twenty-four Beagle dogs were divided into four groups of 6 dogs each. Each group was exposed to an aerosol of different-sized particles of 241 Am oxide: monodisperse particles with AD of 0.75, 1.5 or 3.0 μm; polydisperse particles with AMAD = 1.5 μm. Three dogs in each group were treated with 5 lung lavages of the right lung (day 2, 7, 14, 28 and 42), and 5 lavages of the left lung (days 2, 10, 21, 35, and 49). In addition, each of the treated dogs was given 22 μmoles of trisodium calcium diethylenetriaminepentaacetate (Na 3 Ca DTPA) by intravenous injection 18 times from day 1 to 52 after exposure. The remaining 3 dogs in each group were untreated control dogs. All of the dogs were sacrificed 64 days after exposure and tissues, excreta, and lavage fluids were analyzed for 241 Am activity. Tissue distribution of 241 Am activity at sacrifice varied with aerosol particle size. Less 241 Am activity was found in the lungs of the dogs exposed to 0.75 and 1.5 μm AD aerosols groups than in those exposed to 3.0 μm particles. Lung lavage removed from 24 to 58% of the initial lung burden (ILB). Particle size did not affect the usefulness of lung lavage but it did influence the effectiveness of Na 3 Ca DTPA treatment. Na 3 Ca DTPA enhanced urinary excretion of 241 Am; dogs exposed to 0.75 μm particles excreted 31% of the ILB, and those exposed to 3.0 μm particles excreted only 10%. This experiment showed the effectiveness of combined treatment with lung lavage and chelation therapy for the removal of 241 Am oxide in the first 64 days after exposure. (author)

Plutonium AMS measurements in Yangtze River estuary sediment

International Nuclear Information System (INIS)

Tims, S.G.; Pan, S.M.; Zhang, R.; Fifield, L.K.; Wang, Y.P.; Gao, J.H.

2010-01-01

The Yangtze River is the largest single source of sediment to the continental shelf of the East China Sea. The quantity of material exported by the river is expected to decrease substantially as a consequence of an extensive continuing program of dam construction within the river catchment. We report here AMS measurements of plutonium isotope concentrations and ratios for selected depth increments from a sediment core, collected from the sub-aqueous delta of the Yangtze River estuary. The Pu derives from atmospheric nuclear weapons testing in the 1950s and 1960s, and is potentially a useful tracer of sediment deposition times in the marine environment. The results show considerable structure in the depth-concentration profile, and offer an excellent opportunity to compare Pu with the more commonly used 137 Cs isotopic tracer. The AMS data show superior sensitivity and indicate that the 240 Pu/ 239 Pu ratio can provide a check on the deposition dates. The changes in the 240 Pu and 239 Pu concentrations and the 240 Pu/ 239 Pu ratios with sediment depth all indicate the possibility of using Pu as a geochronological tool for coastal sediment studies.

Beryllium-10: Half-life and AMS-standards

International Nuclear Information System (INIS)

Hofmann, H.J.; Beer, J.; Bonani, G.; von Gunten, H.R.; Raman, S.; Suter, M.; Walker, R.L.; Woelfli, W.; Zimmermann, D.

1987-01-01

Absolute AMS measurements of 10 Be require reliable standards for calibration. Among the existing standards, rather large differences have been observed. These differences were found partially to be due to the different half-life values which were assumed. Also for comparison of AMS data with activity measurements, it is necessary to know the 10 Be half-life as precisely as possible. Starting with 5 ml of the standardized ORNL-MASTER solution, a working solution with a well-defined 10 Be content was prepared. Its specific activity was determined by liquid scintillation counting. This measurement yielded a new value of (1.52 +- 0.05) My for the 10 Be half-life, which is in agreement with the previously reported values but is about three times more accurate. Two independent dilution series produced new AMS standards with 10 Be/ 9 Be ratios of the order of 10 -10 and 10 -11 . These standards were measured at the ETH/SIN AMS facility with high accuracy and are compared with other available 10 Be standards. 15 refs, 2 figs., 3 tabs

sup 241 Am distribution and retention in pregnant mice, in their offspring and in non-pregnant mice: comparison between continuous Am administration and single injection

Energy Technology Data Exchange (ETDEWEB)

Huevel, R. Van Den; Vander Plaetse, F.; Leppens, H.; Schoeters, G. (Centre d' Etude de l' Energie Nucleaire, Mol (Belgium))

1992-01-01

Pregnant BALB/c mice and age and sex matched nulliparous controls were contaminated with {sup 241}Am (13 kBq per mouse). Five days after the termination of contamination, {sup 241}Am incorporation was measured in the tissues of adults and in the liver an the femur of newborn and one-month-old mice. Pregnancy resulted in higher {sup 241}Am concentrations in bone but lower concentrations in the liver of the mothers. Protracted administration of {sup 241}Am compared to a single injection resulted in a lower concentration of {sup 241}Am in the livers of pregnant mice, their nulliparous controls and from newborn mice. The higher {sup 241}Am concentration in the femur at birth after protected exposure before 14 days of gestation compared to protracted exposure after 14 days of gestation could reflect the increased placental transfer of {sup 241}Am with advancing gestational age. Radiation doses to the femur were estimated between 4 and 20 mGy. Haemopoietic changes were noticed at these dose levels in all groups until at least 6 months after birth. (author).

Towards direction dependent fluxes with AMS-02

Energy Technology Data Exchange (ETDEWEB)

Zeissler, Stefan; Andeen, Karen; Boer, Wim de; Gebauer, Iris; Merx, Carmen; Nikonov, Nikolay; Vagelli, Valerio [Karlsruher Institut fuer Technologie KIT (Germany)

2015-07-01

The Alpha Magnetic Spectrometer (AMS-02) is a state-of-the-art particle physics detector designed to operate as an external module on the International Space Station (ISS). In the unique space environment cosmic particles can be measured with high precision over an energy range from GeV up to TeV. In 2014 electron and positron flux measurements where published which indicate an additional source of positrons among the various cosmic particles. The arrival directions of energetic positrons and electrons convey fundamental information on their origin. We evaluate the AMS-02 detector acceptance for each incoming particle direction and show preliminary results of a direction dependent measurement of the AMS-02 lepton flux.

Ion sources in AMS

International Nuclear Information System (INIS)

Iyer, Indira S.

1997-01-01

Accelerator Mass Spectrometry (AMS) entails the sputtering of various samples in an ion source followed by high precision mass analysis of the sputtered ion species in a Tandem Electrostatic Accelerator. A brief account is given

A decade of AMS at the University of Georgia

Science.gov (United States)

Culp, Randy; Noakes, John; Cherkinsky, Alex; Ravi Prasad, G. V.; Dvoracek, Doug

2013-01-01

In a span of 10 years, the University of Georgia’s Center for Applied Isotope Studies (CAIS) has transformed itself from principally a liquid scintillation counting (LSC) laboratory to one conducting thousands of accelerator mass spectrometry (AMS) and stable isotope ratio analysis (SIRA) annually. After receiving the first of the NEC compact AMS units in the United States, the CAIS began to meet the demand for 14C analysis outside the normal realm of most radiocarbon dating laboratories. With industry’s support, isotope research continued on an already developing natural products program to authenticate materials origin and process of formation. The CAIS’s AMS allowed for the detection of synthetic materials in milligram quantities rather than gram quantities required by LSC and allowed new compound specific SIRA techniques to be directed toward compound specific 14C measurement. By 2005 the CAIS was one of only a few laboratories accredited to determine bio-base content in industrial fuels and products by both AMS and LSC following ASTM D6866-10 [1]. Since 2001, when our first sample was analyzed by AMS method, both radiocarbon and natural products sample numbers have increased steadily. The advantages of AMS analysis in overall efficiency, cost savings, accuracy, and precision, are detailed here in a review of analytical precision for radiocarbon and natural products analyzed over 10 years of AMS operation. Comparisons are made between natural products and bio-based materials analyzed by both AMS and LSC. Although high precision is not required to authenticate natural products, for the purpose of product comparison with regard to degree of naturalness accurate and precise 14C measurement is shown to be achievable by both methods.

Chemical Explosion Experiments to Improve Nuclear Test Monitoring - Developing a New Paradigm for Nuclear Test Monitoring with the Source Physics Experiments (SPE)

International Nuclear Information System (INIS)

Snelson, Catherine M.; Abbott, Robert E.; Broome, Scott T.; Mellors, Robert J.; Patton, Howard J.; Sussman, Aviva J.; Townsend, Margaret J.; Walter, William R.

2013-01-01

A series of chemical explosions, called the Source Physics Experiments (SPE), is being conducted under the auspices of the U.S. Department of Energy's National Nuclear Security Administration (NNSA) to develop a new more physics-based paradigm for nuclear test monitoring. Currently, monitoring relies on semi-empirical models to discriminate explosions from earthquakes and to estimate key parameters such as yield. While these models have been highly successful monitoring established test sites, there is concern that future tests could occur in media and at scale depths of burial outside of our empirical experience. This is highlighted by North Korean tests, which exhibit poor performance of a reliable discriminant, mb:Ms (Selby et al., 2012), possibly due to source emplacement and differences in seismic responses for nascent and established test sites. The goal of SPE is to replace these semi-empirical relationships with numerical techniques grounded in a physical basis and thus applicable to any geologic setting or depth

Section thickness-dependent tensile properties of squeeze cast magnesium alloy AM60

Directory of Open Access Journals (Sweden)

Xuezhi Zhang

2012-05-01

Full Text Available The development of alternative casting processes is essential for the high demand of light weight magnesium components to be used in the automotive industry, which often contain different section thicknesses. Squeeze casting with its inherent advantages has been approved for the capability of minimizing the gas porosity in magnesium alloys. For advanced engineering design of light magnesium automotive applications, it is critical to understand the effect of section thickness on mechanical properties of squeeze cast magnesium alloys. In this study, magnesium alloy AM60 with different section thicknesses of 6, 10 and 20 mm squeeze cast under an applied pressure of 30 MPa was investigated. The prepared squeeze cast AM60 specimens were tensile tested at room termperature. The results indicate that the mechanical properties including yield strength (YS, ultimate tensile strength (UTS and elongation (A decrease with an increase in section thickness of squeeze cast AM60. The microstructure analysis shows that the improvement in the tensile behavior of squeeze cast AM60 is primarily attributed to the low-gas porosity level and fine grain strucuture which result from the variation of cooling rate of different section thickness. The numerical simulation (Magmasoft? was employed to determine the solidification rates of each step, and the simulated results show that the solidification rate of the alloy decreases with an increase in the section thickness. The computed solidification rates support the experimental observation on grain structural development.

AMS: Area Message Service for SLC

International Nuclear Information System (INIS)

Crane, M.; Mackenzie, R.; Millsom, D.; Zelazny, M.

1993-04-01

The Area Message Service (AMS) is a TCP/IP based messaging service currently in use at SLAC. A number of projects under development here at SLAC require and application level interface to the 4.3BSD UNIX socket level communications functions using TCP/IP over ethernet. AMS provides connection management, solicited message transfer, unsolicited message transfer, and asynchronous notification of pending messages. AMS is written completely in ANSI 'C' and is currently portable over three hardware/operating system/network manager platforms, VAX/VMS/Multinet, PC/MS-DOS/Pathworks, VME 68K/pSOS/pNA. The basic architecture is a client-server connection where either end of the interface may be the server. This allows for connections and data flow to be initiated from either end of the interface. Included in the paper are details concerning the connection management, the handling of the multi-platform code, and the implementation process

The transmutation of americium: the Ecrix experiments in Phenix

International Nuclear Information System (INIS)

Garnier, J.C.; Schmidt, N.; Croixmarie, Y.; Ottaviani, J.P.; Varaine, F.; Saint Jean, C. de

1999-01-01

The first americium transmutation experiment in a specific target in PHENIX will occur with the ECRIX-B and ECRIX-H experiments. Beside material testing, the objective is also to represent a concept of transmutation whose specificity is to enhance the kinetics of transmutation by using a moderated spectrum. The moderator materials will be 11 B 4 C and CaH 2 for ECRIX-B and ECRIXH respectively, the irradiation conditions have been predicted for both the neutronics and thermal. The targets (MgO-AmO X pellets) are manufactured in the ATALANTE laboratory and the design is performed according to the PHENIX operating conditions. (authors)

SystemC and systemC-AMS in practice systemC 2.3, 2.2 and systemC-AMS 1.0

CERN Document Server

Banerjee, Amal

2013-01-01

This book describes how engineers can make optimum use of the two industry standard analysis/design tools, SystemC and SystemC-AMS.  The authors use a system-level design approach, emphasizing how SystemC and SystemC-AMS features can be exploited most effectively to analyze/understand a given electronic system and explore the design space. The approach taken by this book enables system engineers to concentrate on only those SystemC/SystemC-AMS features that apply to their particular problem, leading to more efficient design. The presentation includes numerous, realistic and complete examples,

Large scale FCI experiments in subassembly geometry. Test facility and model experiments

International Nuclear Information System (INIS)

Beutel, H.; Gast, K.

A program is outlined for the study of fuel/coolant interaction under SNR conditions. The program consists of a) under water explosion experiments with full size models of the SNR-core, in which the fuel/coolant system is simulated by a pyrotechnic mixture. b) large scale fuel/coolant interaction experiments with up to 5kg of molten UO 2 interacting with liquid sodium at 300 deg C to 600 deg C in a highly instrumented test facility simulating an SNR subassembly. The experimental results will be compared to theoretical models under development at Karlsruhe. Commencement of the experiments is expected for the beginning of 1975

Resource for the Development of Biomedical Accelerator Mass Spectrometry (AMS)

Energy Technology Data Exchange (ETDEWEB)

Turteltaub, K. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bench, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Buchholz, B. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Enright, H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kulp, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McCartt, A. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Malfatti, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ognibene, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Loots, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Stewart, B. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2016-04-08

The NIH Research Resource for Biomedical AMS was originally funded at Lawrence Livermore National Laboratory in 1999 to develop and apply the technology of accelerator mass spectrometry (AMS) in broad- based biomedical research. The Resource’s niche is to fill needs for ultra high sensitivity quantitation when isotope-labeled agents are used. The Research Resource’s Technology Research and Development (TR&D) efforts will focus on the needs of the biomedical research community in the context of seven Driving Biomedical Projects (DBPs) that will drive the Center’s technical capabilities through three core TR&Ds. We will expand our present capabilities by developing a fully integrated HPLC AMS to increase our capabilities for metabolic measurements, we will develop methods to understand cellular processes and we will develop and validate methods for the application of AMS in human studies, which is a growing area of demand by collaborators and service users. In addition, we will continue to support new and ongoing collaborative and service projects that require the capabilities of the Resource. The Center will continue to train researchers in the use of the AMS capabilities being developed, and the results of all efforts will be widely disseminated to advance progress in biomedical research. Towards these goals, our specific aims are to:1.) Increase the value and information content of AMS measurements by combining molecular speciation with quantitation of defined macromolecular isolates. Specifically, develop and validate methods for macromolecule labeling, characterization and quantitation.2.) Develop and validate methods and strategies to enable AMS to become more broadly used in human studies. Specifically, demonstrate robust methods for conducting pharmacokinetic/pharmacodynamics studies in humans and model systems.3.) Increase the accessibility of AMS to the Biomedical research community and the throughput of AMS through direct coupling to separatory

Resource for the Development of Biomedical Accelerator Mass Spectrometry (AMS)

Energy Technology Data Exchange (ETDEWEB)

Tuerteltaub, K. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bench, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Buchholz, B. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Enright, H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kulp, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Loots, G. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McCartt, A. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Malfatti, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ognibene, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Stewart, B. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2017-03-21

The NIH Research Resource for Biomedical AMS was originally funded at Lawrence Livermore National Laboratory in 1999 to develop and apply the technology of accelerator mass spectrometry (AMS) in broad- based biomedical research. The Resource’s niche is to fill needs for ultra high sensitivity quantitation when isotope-labeled agents are used. The Research Resource’s Technology Research and Development (TR&D) efforts will focus on the needs of the biomedical research community in the context of seven Driving Biomedical Projects (DBPs) that will drive the Center’s technical capabilities through three core TR&Ds. We will expand our present capabilities by developing a fully integrated HPLC AMS to increase our capabilities for metabolic measurements, we will develop methods to understand cellular processes and we will develop and validate methods for the application of AMS in human studies, which is a growing area of demand by collaborators and service users. In addition, we will continue to support new and ongoing collaborative and service projects that require the capabilities of the Resource. The Center will continue to train researchers in the use of the AMS capabilities being developed, and the results of all efforts will be widely disseminated to advance progress in biomedical research. Towards these goals, our specific aims are to:1.) Increase the value and information content of AMS measurements by combining molecular speciation with quantitation of defined macromolecular isolates. Specifically, develop and validate methods for macromolecule labeling, characterization and quantitation.2.) Develop and validate methods and strategies to enable AMS to become more broadly used in human studies. Specifically, demonstrate robust methods for conducting pharmacokinetic/pharmacodynamics studies in humans and model systems.3.) Increase the accessibility of AMS to the Biomedical research community and the throughput of AMS through direct coupling to separatory

The actinide beamline - A new AMS facility at ANTARES

International Nuclear Information System (INIS)

Hotchkis, M.A.C.; Lee, P.J.; Mino, N.

1998-01-01

At the ANTARES accelerator a new beamline has been commissioned, incorporating new magnetic and electrostatic analysers, to optimise the efficiency for Actinides detection by Accelerator Mass Spectrometry. The detection of Actinides, particularly the isotopic ratios of uranium and plutonium, provide unique signatures for nuclear safeguards purposes. We are currently engaged in a project to evaluate the application of AMS to the measurement of Actinides in environmental samples for nuclear safeguards. Measurement of 236 U is of particular interest as a means of tracing the anthropogenic component of uranium. 236 U is expected to be present in natural samples at an extremely low level ( 236 U: 238 U ratio ∼10 -10 ). It has recently been demonstrated that AMS has sufficient sensitivity to detect 236 U at this level. The principal components of the new beamline include: an electrostatic quadrupole, a 12 deg electrostatic deflector, a 90 deg electrostatic analyser, a multi-isotope detection system including ion counters and Faraday cups. The beamline was completed in September 1998 and initial tests have been performed with iodine samples

Biochemical paths in humans and cells: Frontiers of AMS bioanalysis

International Nuclear Information System (INIS)

Vogel, J.S.; Palmblad, N.M.; Ognibene, T.; Kabir, M.M.; Buchholz, B.A.; Bench, G.

2007-01-01

The publication rate of 3 H and 14 C use in biomedical research decreased by a factor of three since 1990 when the first applications of AMS in biomedicine were published. Against this decrease, the high sensitivity of AMS for these isotopes in small isolated samples has made significant contributions. New smaller spectrometers and increased commercial availability of AMS have solved some of the issues surrounding availability and cost, but improved quantitation in non-isotopic methods now compete with some early uses of AMS. We review the strength of AMS for quantifying rare biochemical events and chemical passages through individual people or cells and consider these as the frontiers of quantitation leading to profitable science unavailable to other techniques

Benefits of high gradient solidification for creep and low cycle fatigue of AM1 single crystal superalloy

Energy Technology Data Exchange (ETDEWEB)

Steuer, S., E-mail: Susanne.Steuer@ensma.fr [Institut Pprime, CNRS – ENSMA – Université de Poitiers, UPR CNRS 3346, Department of Physics and Mechanics of Materials, ENSMA – Téléport 2, 1 avenue Clément Ader, BP 40109, 86961 Futuroscope Chasseneuil Cedex (France); Villechaise, P. [Institut Pprime, CNRS – ENSMA – Université de Poitiers, UPR CNRS 3346, Department of Physics and Mechanics of Materials, ENSMA – Téléport 2, 1 avenue Clément Ader, BP 40109, 86961 Futuroscope Chasseneuil Cedex (France); Pollock, T.M. [Materials Department, University of California Santa Barbara, Santa Barbara, CA 93106-5050 (United States); Cormier, J. [Institut Pprime, CNRS – ENSMA – Université de Poitiers, UPR CNRS 3346, Department of Physics and Mechanics of Materials, ENSMA – Téléport 2, 1 avenue Clément Ader, BP 40109, 86961 Futuroscope Chasseneuil Cedex (France)

2015-10-01

The influence of high thermal gradient processing on the creep and low cycle fatigue properties of the AM1 Ni-based single crystal superalloy has been studied. Isothermal creep (from 750 °C up to 1200 °C) and low cycle fatigue (750 °C and 950 °C) experiments were performed for AM1 alloy solidified with a conventional radiation cooled (Bridgman) and higher thermal gradient liquid-metal cooled (LMC) casting process to produce coarse and finer-scaled dendritic structures, respectively. There was no significant effect of the casting technique on creep properties, due to the very similar microstructures (γ′-size and γ-channel width) established after full heat treatment of both Bridgman and LMC samples. For low cycle fatigue properties, the benefit of the higher gradient LMC process was dependent on the testing temperature. At 750 °C, cracks primarily initiated at pores created by solidification shrinkage in both Bridgman and LMC samples. Samples produced by the LMC technique demonstrated fatigue lives up to 4 times longer, compared to the Bridgman samples, due to refined porosity. At 950 °C the low cycle fatigue properties of the LMC and conventionally solidified material were not distinguishable due to a shift of crack initiation sites from internal pores to oxidized surface layers or near-surface pores. The benefit of the LMC approach was, however, apparent in fatigue at 950 °C when testing in a vacuum environment. Based on these results, a crack initiation model based on the local slip activity close to casting defect is proposed.

Field study of the migration of 237Np, 238Pu and 241Am in a weak loess aquifer

International Nuclear Information System (INIS)

Liu, C.L.; Wang, Z.M.; Li, S.S.; Yang, Y.E.; Li, B.; Jiang, H.; Jiang, L.; Wang, L.; Li, D.

2004-01-01

The migration of 237 Np, 238 Pu and 241 Am in a weak loess aquifer was investigated in-situ in an Underground Research Facility. Quartz containing 237 Np, 238 Pu, 241 Am and 3 H was introduced into the aquifer with a stainless steel tube. The local water flow in the aquifer was monitored using a 3-dimensional sampling system. The contaminated area of the aquifer was obtained wholly with the help of a pre-installed stainless steel frame and cut into small pieces (samples) 3-dimensionally and analyzed. 3 H in the water samples was determined with a liquid scintillation analyzer (Tri-Camb 2250). Radioactivity of 237 Np and 241 Am in the soil samples were determined with a low energy photon detector (HPGe), 238 Pu was analyzed with a low background αandβ detector after chemical separation. The result of the 3-year experiment indicated that 237 Np, 238 Pu and 241 Am were strongly absorbed by the loess aquifer. The retardation factor of 237 Np in the loess aquifer was 1.54 x 10 4 . (author)

Large block migration experiments: INTRAVAL phase 1, Test Case 9

Energy Technology Data Exchange (ETDEWEB)

Gureghian, A.B.; Noronha, C.J. (Battelle, Willowbrook, IL (USA). Office of Waste Technology Development); Vandergraaf, T.T. (Atomic Energy of Canada Ltd., Ottawa, ON (Canada))

1990-08-01

The development of INTRAVAL Test Case 9, as presented in this report, was made possible by a past subsidiary agreement to the bilateral cooperative agreement between the US Department of Energy (DOE) and Atomic Energy of Canada Limited (AECL) encompassing various aspects of nuclear waste disposal research. The experimental aspect of this test case, which included a series of laboratory experiments designed to quantify the migration of tracers in a single, natural fracture, was undertaken by AECL. The numerical simulation of the results of these experiments was performed by the Battelle Office of Waste Technology Development (OWTD) by calibrating an in-house analytical code, FRACFLO, which is capable of predicting radionuclide transport in an idealized fractured rock. Three tracer migration experiments were performed, using nonsorbing uranine dye for two of them and sorbing Cs-137 for the third. In addition, separate batch experiments were performed to determine the fracture surface and rock matrix sorption coefficients for Cs-137. The two uranine tracer migration experiment were used to calculate the average fracture aperture and to calibrate the model for the fracture dispersivity and matrix diffusion coefficient. The predictive capability of the model was then tested by simulating the third, Cs-137, tracer test without changing the parameter values determined from the other experiments. Breakthrough curves of both the experimental and numerical results obtained at the outlet face of the fracture are presented for each experiment. The reported spatial concentration profiles for the rock matrix are based solely on numerical predictions. 22 refs., 12 figs., 8 tabs.

Indirect and inclusive search for dark matter with AMS02 space spectrometer

International Nuclear Information System (INIS)

Brun, P.

2007-06-01

AMS02 is a particle physics detector designed for 3 years of data collecting aboard the International Space Station. Equipped with a superconducting magnet, it will allow to measure gamma and cosmic ray fluxes in the GeV to TeV region with high particle identification capabilities. Its performance is based on the redundancy of measurements in specific sub-detectors: a Time-Of-Flight counter, a Transition Radiation Detector, a Silicon Tracker, a Ring Imaging Cherenkov counter and an Electromagnetic calorimeter (Ecal). The Ecal is studied in details, in particular with the qualification of a stand-alone trigger devoted to gamma ray astronomy. This system allows the increase of the AMS02 sensitivity to photons, and the improvement of the reconstruction of electromagnetic events. The analog part of the trigger system has been tested with test benches and with a beam at CERN. The in-orbit calibration of the Ecal is studied, it may proceed in two steps. First, the Ecal cells responses have to be equalized with minimum ionizing particles data. Then an absolute calibration can be performed with cosmic electrons. For both the relative and the absolute calibration, possible procedures are defined and realistic calibration times are estimated. The second part deals with the indirect searches for dark matter and the study of the AMS02 sensitivity. Dark matter stands for 84% of the Universe mass and could consist in new particles. Dark matter particles are expected to surround our Galaxy and annihilate in high density regions. These annihilations could become observable exotic primary cosmic ray sources. Searches for anomalous excesses in (p-bar, e + , D-bar) and γ ray fluxes will be performed by AMS02. A numerical tool allowing us to perform predictions for these exotic fluxes within supersymmetry or extra-dimension is developed and is presented in details. Phenomenological studies regarding possible enhancements of these signals by over-dense regions of the halo have also

AMS data production facilities at science operations center at CERN

Science.gov (United States)

Choutko, V.; Egorov, A.; Eline, A.; Shan, B.

2017-10-01

The Alpha Magnetic Spectrometer (AMS) is a high energy physics experiment on the board of the International Space Station (ISS). This paper presents the hardware and software facilities of Science Operation Center (SOC) at CERN. Data Production is built around production server - a scalable distributed service which links together a set of different programming modules for science data transformation and reconstruction. The server has the capacity to manage 1000 paralleled job producers, i.e. up to 32K logical processors. Monitoring and management tool with Production GUI is also described.

Biosorption of Am-241 and Cs-137 by radioactive liquid waste by coffee husk

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Rafael Vicente de Padua; Sakata, Solange Kazumi; Bellini, Maria Helena; Marumo, Julio Takehiro, E-mail: jtmarumo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-07-01

Radioactive Waste Management Laboratory of Nuclear and Energy Research Institute, IPEN-CNEN/SP, has stored many types of radioactive liquid wastes, including liquid scintillators, mixed wastes from chemical analysis and spent decontamination solutions. These wastes need special attention, because the available treatment processes are often expensive and difficult to manage. Biosorption using biomass of vegetable using agricultural waste has become a very attractive technique because it involves the removal of heavy metals ions by low cost biossorbents. The aim of this study is to evaluate the potential of the coffee husk to remove Am-241 and Cs-137 from radioactive liquid waste. The coffee husk was tested in two forms, treated and untreated. The chemical treatment of the coffee husk was performed with HNO{sub 3} and NaOH diluted solutions. The results showed that the coffee husk did not showed significant differences in behavior and capacity for biosorption for Am-241 and Cs-137 over time. Coffee husk showed low biosorption capacity for Cs-137, removing only 7.2 {+-} 1.0% in 4 hours of contact time. For Am-241, the maximum biosorption was 57,5 {+-} 0.6% in 1 hours. These results suggest that coffee husk in untreated form can be used in the treatment of radioactive waste liquid containing Am-241. (author)

Application Research of Quasi-monochromatic X-ray Machine Replacing 241Am Radioactive Source in Thickness Measurement

Directory of Open Access Journals (Sweden)

LIN Hui1;XIAO Xue-fu2;HOU Yue-xin3;ZHAO Jing1;JIAN Li-min1

2014-02-01

Full Text Available In the research of BS-03 thickness detector, a self-designed quasi-monochromatic (50-60 keV X-ray machine was studied as a substitution to Am-241 low energy photon source（1.11×109 Bq）The range of output current, the attenuation of X rays through the steel plate, the aluminum plate, and the organic glass plate and stability of quasi-monochromatic X-ray machine was tested. The result showed that quasi-monochromatic X-ray machine could be an applicable replacement of Am-241 radioactive source.

Performance of core exit thermocouple for PWR accident management action in vessel top break LOCA simulation experiment at OECD/NEA ROSA project

International Nuclear Information System (INIS)

Suzuki, Mitsuhiro; Takeda, Takeshi; Nakamura, Hideo

2009-01-01

Presented are experiment results of the Large Scale Test Facility (LSTF) conducted at the Japan Atomic Energy Agency (JAEA) with a focus on core exit thermocouple (CET) performance to detect core overheat during a vessel top break loss-of-coolant accident (LOCA) simulation experiment. The CET temperatures are used to start accident management (AM) action to quickly depressurize steam generator (SG) secondary side in case of core temperature excursion. Test 6-1 is first test of the OECD/NEA ROSA Project started in 2005, simulating withdraw of a control rod drive mechanism penetration nozzle at the vessel top head. The break size is equivalent to 1.9% cold leg break. The AM action was initiated when CET temperature rose up to 623K. There was no reflux water fallback onto the CETs during the core heat-up period. The core overheat, however, was detected with a time delay of about 230s. In addition, a large temperature discrepancy was observed between the CETs and the hottest core region. This paper clarifies the reason of time delay and temperature discrepancy between the CETs and heated core during boil-off including three-dimensional steam flows in the core and core exit. The paper discusses applicability of the LSTF CET performance to pressurized water reactor (PWR) conditions and a possibility of alternative indicators for earlier AM action than in Test 6-1 is studied by using symptom-based plant parameters such as a reactor vessel water level detection. (author)

Indirect search for dark matter with AMS

International Nuclear Information System (INIS)

Goy, Corinne

2006-01-01

This document summarises the potential of AMS in the indirect search for Dark Matter. Observations and cosmology indicate that the Universe may include a large amount of Dark Matter of unknown nature. A good candidate is the Ligthest Supersymmetric Particle in R-Parity conserving models. AMS offers a unique opportunity to study Dark Matter indirect signature in three spectra: gamma, antiprotons and positrons

AMS: Area Message Service for SLC

International Nuclear Information System (INIS)

Crane, M.; Mackenzie, R.; Millsom, D.; Zelazny, M.

1993-01-01

The Area Message Service (AMS) is a TCP/IP based messaging service currently in use at SLAC. A number of projects under development here at SLAC require an application level interface to the 4.3BSD UNIX socket level communications functions using TCP/IP over ethernet. AMS provides connection management, solicited message transfer, unsolicited message transfer, and asynchronous notification of pending messages. AMS is written completely in ANSI open-quote C close-quote and is currently portable over three hardware/operating system/network manager platforms, VAX/VMS/Multinet, PC/MS-DOS/Pathworks, VME 68K/pSOS/pNA. The basic architecture is a client-server connection where either end of the interface may be the server. This allows for connections and data flow to be initiated from either end of the interface. Included in the paper are details concerning the connection management, the handling of the multi-platform code, and the implementation process

The ETH Zurich AMS facilities: Performance parameters and reference materials

Energy Technology Data Exchange (ETDEWEB)

Christl, M., E-mail: mchristl@phys.ethz.ch [Laboratory of Ion Beam Physics, ETH Zurich, 8093 Zurich (Switzerland); Vockenhuber, C.; Kubik, P.W.; Wacker, L.; Lachner, J.; Alfimov, V.; Synal, H.-A. [Laboratory of Ion Beam Physics, ETH Zurich, 8093 Zurich (Switzerland)

2013-01-15

The current performance of all three AMS systems in operation at ETH Zurich, the 6 MV HVEC EN-Tandem facility 'TANDEM', the 0.5 MV NEC Pelletron 'TANDY', and the 0.2 MV system 'MICADAS' is summarized. Radionuclides routinely measured with these AMS systems include {sup 10}Be, {sup 14}C, {sup 26}Al, {sup 36}Cl, {sup 41}Ca, {sup 129}I and the actinides. The reference materials used for the normalization of the AMS measurements at the ETH Zurich AMS facilities are presented. This paper therefore is a comprehensive status report of all three AMS systems currently operated by the Laboratory of Ion Beam Physics (LIP) at ETH Zurich and documents their performance and operation parameters.

Post-test analysis of ROSA-III experiment Run 702

International Nuclear Information System (INIS)

Koizumi, Yasuo; Kikuchi, Osamu; Soda, Kunihisa

1980-01-01

The purpose of the ROSA-III experiment with a scaled BWR test facility is to examine primary coolant thermal-hydraulic behavior and performance of ECCS during a posturated loss-of-coolant accident of BWR. The results provide information for verification and improvement of reactor safety analysis codes. Run 702 assumed a 200% split break at the recirculation pump suction line under an average core power without ECCS activation. Post - test analysis of the Run 702 experiment was made with computer code RELAP4J. Agreement of the calculated system pressure and the experiment one was good. However, the calculated heater surface temperatures were higher than the measured ones. Also, the axial temperature distribution was different in tendency from the experimental one. From these results, the necessity was indicated of improving the analytical model of void distribution in the core and the nodalization in the pressure vassel, in order to make the analysis more realistic. And also, the need of characteristic test was indicated for ROSA-III test facility components, such as jet pump and piping form loss coefficient; likewise, flow rate measurements must be increased and refined. (author)

Some problems in mechanics of growing solids with applications to AM technologies

Science.gov (United States)

Manzhirov, A. V.

2018-04-01

Additive Manufacturing (AM) technologies are an exciting area of the modern industrial revolution and have applications in engineering, medicine, electronics, aerospace industry, etc. AM enables cost-effective production of customized geometry and parts by direct fabrication from 3D data and mathematical models. Despite much progress in AM technologies, problems of mechanical analysis for AM fabricated parts yet remain to be solved. This paper deals with three main mechanical problems: the onset of residual stresses, which occur in the AM process and can lead to failure of the parts, the distortion of the final shape of AM fabricated parts, and the development of technological solutions aimed at improving existing AM technologies and creating new ones. An approach proposed deals with the construction of adequate analytical model and effective methods for the simulation of AM processes for fabricated solid parts.

LANDSAT-D data format control book. Volume 6, appendix G: GSFC HDT-AM inventory tape (GHIT-AM)

Science.gov (United States)

1981-01-01

The data format specifications of the Goddard HDT inventory tapes (GHITS), which accompany shipments of archival digital multispectral scanner image data (HDT-AM tapes), are defined. The GHIT is a nine-track, 1600-BPI tape which conforms to the ANSI standard and serves as an inventory and description of the image data included in the shipment. The archival MSS tapes (HDT-AMs) contain radiometrically corrected but geometrically uncorrected image data plus certain ancillary data necessary to perform the geometric corrections.

Experiences in stability testing of boiling water reactors

International Nuclear Information System (INIS)

March-Leuba, J.; Otaduy, P.J.

1986-01-01

The purpose of this paper is to summarize experiences with boiling water reactor (BWR) stability testing using noise analysis techniques. These techniques have been studied over an extended period of time, but it has been only recently that they have been well established and generally accepted. This paper contains first a review of the problem of BWR neutronic stability, focusing on its physical causes and its effects on reactor operation. The paper also describes the main techniques used to quantify, from noise measurements, the reactor's stability in terms of a decay ratio. Finally, the main results and experiences obtained from the stability tests performed at the Dresden and the Browns Ferry reactors using noise analysis techniques are summarized

JOSÉ MARTÍ - život a dílo se zaměřením na jeho eseje Madre América a Nuestra América

OpenAIRE

Bočková, Sandra

2015-01-01

In my Bachelor thesis entitled "JOSÉ MARTÍ - life and work with orientation to his essays Madre América and Nuestra América" I am going to pursue two of his principal essays titled Madre América and Nuestra América which contain Marti's ideas related to the self- determination of the nations of Latin America. In order to analyse the respective themes, I consider necessary to introduce the author first. In my opinion, José Martí is one of the most important figures in the Cuban colonial era; h...

AM Envelope. The potential of Additive Manufacturing for facade constructions

Directory of Open Access Journals (Sweden)

Holger Strauss

2017-11-01

Full Text Available This dissertation shows the potential of Additive Manufacturing (AM for the development of building envelopes: AM will change the way of designing facades, how we engineer and produce them. To achieve today’s demands from those future envelopes, we have to find new solutions. New technologies offer one possible way to do so. They open new approaches in designing, producing and processing building construction and facades. Finding the one capable of having big impact is difficult – Additive Manufacturing is one possible answer. The term ‘AM Envelope’ (Additive Manufacturing Envelope describes the transfer of this technology to the building envelope. Additive Fabrication is a building block that aids in developing the building envelope from a mere space enclosure to a dynamic building envelope. First beginnings of AM facade construction show up when dealing with relevant aspects like material consumption, mounting or part’s performance. From those starting points several parts of an existing post-and-beam façade system were optimized, aiming toward the implementation of AM into the production chain. Enhancements on all different levels of production were achieved: storing, producing, mounting and performance. AM offers the opportunity to manufacture facades ‘just in time’. It is no longer necessary to store or produce large numbers of parts in advance. Initial investment for tooling can be avoided, as design improvements can be realized within the dataset of the AM part. AM is based on ‘tool-less’ production, all parts can be further developed with every new generation. Producing tool-less also allows for new shapes and functional parts in small batch sizes – down to batch size one. The parts performance can be re-interpreted based on the demands within the system, not based on the limitations of conventional manufacturing. AM offers new ways of materializing the physical part around its function. It leads toward customized

Surface-specific additive manufacturing test artefacts

Science.gov (United States)

Townsend, Andrew; Racasan, Radu; Blunt, Liam

2018-06-01

Many test artefact designs have been proposed for use with additive manufacturing (AM) systems. These test artefacts have primarily been designed for the evaluation of AM form and dimensional performance. A series of surface-specific measurement test artefacts designed for use in the verification of AM manufacturing processes are proposed here. Surface-specific test artefacts can be made more compact because they do not require the large dimensions needed for accurate dimensional and form measurements. The series of three test artefacts are designed to provide comprehensive information pertaining to the manufactured surface. Measurement possibilities include deviation analysis, surface texture parameter data generation, sub-surface analysis, layer step analysis and build resolution comparison. The test artefacts are designed to provide easy access for measurement using conventional surface measurement techniques, for example, focus variation microscopy, stylus profilometry, confocal microscopy and scanning electron microscopy. Additionally, the test artefacts may be simply visually inspected as a comparative tool, giving a fast indication of process variation between builds. The three test artefacts are small enough to be included in every build and include built-in manufacturing traceability information, making them a convenient physical record of the build.

High-speed photometry of Gaia14aae: an eclipsing AM CVn that challenges formation models

Science.gov (United States)

Green, M. J.; Marsh, T. R.; Steeghs, D. T. H.; Kupfer, T.; Ashley, R. P.; Bloemen, S.; Breedt, E.; Campbell, H. C.; Chakpor, A.; Copperwheat, C. M.; Dhillon, V. S.; Hallinan, G.; Hardy, L. K.; Hermes, J. J.; Kerry, P.; Littlefair, S. P.; Milburn, J.; Parsons, S. G.; Prasert, N.; van Roestel, J.; Sahman, D. I.; Singh, N.

2018-05-01

AM CVn-type systems are ultracompact, hydrogen-deficient accreting binaries with degenerate or semidegenerate donors. The evolutionary history of these systems can be explored by constraining the properties of their donor stars. We present high-speed photometry of Gaia14aae, an AM CVn with a binary period of 49. 7 min and the first AM CVn in which the central white dwarf is fully eclipsed by the donor star. Modelling of the light curves of this system allows for the most precise measurement to date of the donor mass of an AM CVn, and relies only on geometric and well-tested physical assumptions. We find a mass ratio q = M2/M1 = 0.0287 ± 0.0020 and masses M1 = 0.87 ± 0.02 M⊙ and M2 = 0.0250 ± 0.0013 M⊙. We compare these properties to the three proposed channels for AM CVn formation. Our measured donor mass and radius do not fit with the contraction that is predicted for AM CVn donors descended from white dwarfs or helium stars at long orbital periods. The donor properties we measure fall in a region of parameter space in which systems evolved from hydrogen-dominated cataclysmic variables are expected, but such systems should show spectroscopic hydrogen, which is not seen in Gaia14aae. The evolutionary history of this system is therefore not clear. We consider a helium-burning star or an evolved cataclysmic variable to be the most likely progenitors, but both models require additional processes and/or fine-tuning to fit the data. Additionally, we calculate an updated ephemeris which corrects for an anomalous time measurement in the previously published ephemeris.

Linear Aerospike SR-71 Experiment (LASRE) dumps water after first in-flight cold flow test

Science.gov (United States)

1998-01-01

The NASA SR-71A successfully completed its first cold flow flight as part of the NASA/Rocketdyne/Lockheed Martin Linear Aerospike SR-71 Experiment (LASRE) at NASA's Dryden Flight Research Center, Edwards, California on March 4, 1998. During a cold flow flight, gaseous helium and liquid nitrogen are cycled through the linear aerospike engine to check the engine's plumbing system for leaks and to check the engine operating characterisitics. Cold-flow tests must be accomplished successfully before firing the rocket engine experiment in flight. The SR-71 took off at 10:16 a.m. PST. The aircraft flew for one hour and fifty-seven minutes, reaching a maximum speed of Mach 1.58 before landing at Edwards at 12:13 p.m. PST. 'I think all in all we had a good mission today,' Dryden LASRE Project Manager Dave Lux said. Flight crew member Bob Meyer agreed, saying the crew 'thought it was a really good flight.' Dryden Research Pilot Ed Schneider piloted the SR-71 during the mission. Lockheed Martin LASRE Project Manager Carl Meade added, 'We are extremely pleased with today's results. This will help pave the way for the first in-flight engine data-collection flight of the LASRE.' The LASRE experiment was designed to provide in-flight data to help Lockheed Martin evaluate the aerodynamic characteristics and the handling of the SR-71 linear aerospike experiment configuration. The goal of the project was to provide in-flight data to help Lockheed Martin validate the computational predictive tools it was using to determine the aerodynamic performance of a future reusable launch vehicle. The joint NASA, Rocketdyne (now part of Boeing), and Lockheed Martin Linear Aerospike SR-71 Experiment (LASRE) completed seven initial research flights at Dryden Flight Research Center. Two initial flights were used to determine the aerodynamic characteristics of the LASRE apparatus (pod) on the back of the SR-71. Five later flights focused on the experiment itself. Two were used to cycle gaseous

Experiences of the REACH testing proposals system to reduce animal testing.

Science.gov (United States)

Taylor, Katy; Stengel, Wolfgang; Casalegno, Carlotta; Andrew, David

2014-01-01

In order to reduce animal testing, companies registering chemical substances under the EU REACH legislation must propose rather than conduct certain tests on animals. Third parties can submit 'scientifically valid information' relevant to these proposals to the Agency responsible, the European Chemicals Agency (ECHA), who are obliged to take the information into account. The European Coalition to End Animal Experiments (ECEAE) provided comments on nearly half of the 817 proposals for vertebrate tests on 480 substances published for comment for the first REACH deadline (between 1 August 2009 and 31 July 2012). The paper summarises the response by registrants and the Agency to third party comments and highlights issues with the use of read across, in vitro tests, QSAR and weight of evidence approaches. Use of existing data and evidence that testing is legally or scientifically unjustified remain the most successful comments for third parties to submit. There is a worrying conservatism within the Agency regarding the acceptance of alternative approaches and examples of where registrants have also failed to maximise opportunities to avoid testing.

Post-test analysis of the W-2 SLSF experiment

International Nuclear Information System (INIS)

Smith, D.E.; Pitner, A.L.

1983-01-01

The W-2 SLSF experiment was an instrumented in-reactor test performed to characterize the failure response of full-length preconditioned LMFBR prototypical fuel pins to slow transient overpower (TOP) conditions. Although the test results were expected to confirm analytical predictions of upper-level failure and fuel expulsion, an axial midplane failure was experienced. Preliminary interpretations of the cause and implications of midplane failure have been revised. Extensive analyses were conducted in order to understand the unexpected behavior of the experiment. The results of the analyses and their interpretations are presented

Extraction methods for determination of Pu and Am contents in soil samples from the Chernobyl' NPP 30-km zone

International Nuclear Information System (INIS)

Shvetsov, I.K.; Yakovlev, N.G.; Kalinichenko, B.S.; Kulakov, V.M.; Kulazhko, V.G.; Vlasov, M.M.; Shubko, V.M.; Pchelkin, V.A.; Rodionov, Yu.F.; Lisin, S.K.

1989-01-01

The possibilities for decreasing the time of soil sample analysis for Pu, Am, Cm isotope concentrations with simultaneous increasing the sensitivity and analysis representativity are demonstrated. It is achieved due to changing the total sample break-down by oxidizing leaching, and the procedure of ion-exchange separation by single extraction using trioctylamine. Experience in the method applications for analysis of soil samples in the Chernobyl' NPP 30-km zone aimed at determination of correlation coefficients for Pu/Ce-144 and Pu/Am-241 is generalized. 4 refs.; 4 figs.; 1 tab

A new BPM-TOF system for CologneAMS

Energy Technology Data Exchange (ETDEWEB)

Pascovici, Gheorghe; Dewald, Alfred; Heinze, Stefan; Schiffer, Markus; Feuerstein, Mark [CologneAMS, Universitaet Koeln (Germany); Pfeiffer, Michael; Jolie, Jan; Zell, Karl Oskar [IKP, Universitaet Koeln (Germany); Blanckenburg, Friedhelm von [GFZ, Potsdam (Germany)

2011-07-01

At the center for accelerator mass spectrometry (CologneAMS) a complex beam detector consisting of a high resolution Beam Profile Monitor (BPM) and a Time of Flight (TOF) spectrometer with tracking capabilities was designed especially for the needs of the Cologne AMS facility. The complex beam detector assembly is designed to match the beam specifications of the 6MV Tandetron AMS setup and its DAQ system, which is presently in the commissioning phase at the IKP of the University of Cologne. The BPM-TOF system will have a reconfigurable structure, namely: either a very fast TOF subsystem with a small active area or a more complex BPM -TOF detector with beam tracking capabilities and with a large active area. The systems aims for background suppression in case of the spectrometry of heavy ions, e.g. U, Cm, Pu, Am etc. and could also be used as an additional filter e.g., for the isobar {sup 36}S in case of the spectrometry of {sup 36}Cl.

Placental transfer and distribution of 241Am in the rat

International Nuclear Information System (INIS)

Hisamatsu, S.; Takizawa, Y.

1983-01-01

The placental transfer and distribution of 241 Am in the feto-placental system were studied in pregnant rats. Rats were injected intravenously with 241 Am citrate at 15 or 18 days of gestation. Groups injected at 15 days of gestation were sacrificed 2, 24, 48, or 120 hr after injection, and the group injected at 18 days was sacrificed 24 hr after. The radioactivities of 241 Am in fetus, fetal membrane, and placenta were determined, and its distribution in the feto-placental system was investigated by high-speed autoradiography using a silver-activated zinc sulfide-coated membrane as an intensifying screen. The deposition of 241 Am in feto-placenta units increased with the number of days of gestation. Results of autoradiography revealed that major deposition sites of 241 Am in the fetus are the skeleton and liver. Heavy deposition of 241 Am in the yolksac splanchnopleure and its existence in the exocoelom strongly suggest that the yolk sac placenta plays an important role in the placental transfer of this nuclide

X-ray photoelectron spectra structure and chemical bonding in AmO2

Directory of Open Access Journals (Sweden)

Teterin Yury A.

2015-01-01

Full Text Available Quantitative analysis was done of the X-ray photoelectron spectra structure in the binding energy range of 0 eV to ~35 eV for americium dioxide (AmO2 valence electrons. The binding energies and structure of the core electronic shells (~35 eV-1250 eV, as well as the relativistic discrete variation calculation results for the Am63O216 and AmO8 (D4h cluster reflecting Am close environment in AmO2 were taken into account. The experimental data show that the many-body effects and the multiplet splitting contribute to the spectral structure much less than the effects of formation of the outer (0-~15 eV binding energy and the inner (~15 eV-~35 eV binding energy valence molecular orbitals. The filled Am 5f electronic states were shown to form in the AmO2 valence band. The Am 6p electrons participate in formation of both the inner and the outer valence molecular orbitals (bands. The filled Am 6p3/2 and the O 2s electronic shells were found to make the largest contributions to the formation of the inner valence molecular orbitals. Contributions of electrons from different molecular orbitals to the chemical bond in the AmO8 cluster were evaluated. Composition and sequence order of molecular orbitals in the binding energy range 0-~35 eV in AmO2 were established. The experimental and theoretical data allowed a quantitative scheme of molecular orbitals for AmO2, which is fundamental for both understanding the chemical bond nature in americium dioxide and the interpretation of other X-ray spectra of AmO2.

L2 Milestone 5433: Characterization of Dynamic Behavior of AM and Conventionally Processed Stainless Steel (316L and 304L)

Energy Technology Data Exchange (ETDEWEB)

Gray, George Thompson [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Livescu, Veronica [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Rigg, P. A. [Washington State Univ., Pullman, WA (United States). Inst. for Shock Physics; Trujillo, Carl Patrick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cady, Carl McElhinney [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Chen, Shuh-Rong [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Carpenter, John S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lienert, Thomas J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fensin, Saryu Jindal [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Knapp, Cameron M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Beal, Roberta Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Morrow, Benjamin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dippo, Olivia F. [Univ. of California, San Diego, CA (United States); Jones, David Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Martinez, Daniel Tito [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Valdez, James Anthony [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-09-26

For additive manufacturing (AM) of metallic materials, the certification and qualification paradigm needs to evolve as there currently exists no broadly accepted “ASTM- or DIN-type” additive manufacturing certified process or AM-material produced specifications. Accordingly, design, manufacture, and thereafter implementation and insertion of AM materials to meet engineering applications requires detailed quantification of the constitutive (strength and damage) properties of these evolving materials, across the spectrum of metallic AM methods, in comparison/contrast to conventionally-manufactured metals and alloys. This report summarizes the 316L SS research results and presents initial results of the follow-on study of 304L SS. For the AM-316L SS investigation, cylindrical samples of 316L SS were produced using a LENS MR-7 laser additive manufacturing system from Optomec (Albuquerque, NM) equipped with a 1kW Yb-fiber laser. The microstructure of the AM-316L SS was characterized in both the “as-built” Additively Manufactured state and following a heat-treatment designed to obtain full recrystallization to facilitate comparison with annealed wrought 316L SS. The dynamic shock-loading-induced damage evolution and failure response of all three 316L SS materials was quantified using flyer-plate impact driven spallation experiments at peak stresses of 4.5 and 6.35 GPa. The results of these studies are reported in detail in the first section of the report. Publication of the 316L SS results in an archival journal is planned. Following on from the 316L SS completed work, initial results on a study of AM 304L SS are in progress and presented herein. Preliminary results on the structure/dynamic spallation property behavior of AM-304L SS fabricated using both the directed-energy LENS and an EOS powder-bed AM techniques in comparison to wrought 304L SS is detailed in this Level 2 Milestone report.

AmE 2012. Automotive meets electronics

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-11-01

This conference CD contains 19 contributions, which were presented at the AmE 2012. The main topics were: (1) Electrification; (2) High voltage (board networks) and electromagnetic compatibility; (3) Car-to-X and driver assistance; (4) Diagnosis; (5) Electrical systems. Six contributions were recorded separately for the ENERGY database. [German] Diese Tagungs-CD enthaelt 19 Beitraege, die auf der AmE 2012 vorgestellt wurden. Die Themenschwerpunkte waren: 1. Electrification; 2. Hochvolt(-bordnetze) und Elektromagnetische Vertraeglichkeit; 3. Car-to-X und Fahrerassistenz; 4. Diagnose; 5. Bordnetze. Sechs Beitraege wurden separat fuer die ENERGY-Datenbank aufgenommen.

Test Management Framework for the Data Acquisition of the ATLAS Experiment

CERN Document Server

Kazarov, Andrei; The ATLAS collaboration

2017-01-01

Data Acquisition (DAQ) of the ATLAS experiment is a large distributed and inhomogeneous system: it consists of thousands of interconnected computers and electronics devices that operate coherently to read out and select relevant physics data. Advanced testing and diagnostics capabilities of the TDAQ control system are a crucial feature which contributes significantly to smooth operation and fast recovery in case of the problems and, finally, to the high efficiency of the whole experiment. The base layer of the verification and diagnostic functionality is a test management framework. We have developed a flexible test management system that allows the experts to define and configure tests for different components, indicate follow-up actions to test failures and describe inter-dependencies between DAQ or detector elements. This development is based on the experience gained with the previous test system that was used during the first three years of the data taking. We discovered that more emphasis needed to be pu...

Conjugal plasmid transfer (pAM beta 1) in Lactobacillus plantarum.

OpenAIRE

Shrago, A W; Chassy, B M; Dobrogosz, W J

1986-01-01

The streptococcal plasmid pAM beta 1 (erythromycin resistance) was transferred via conjugation from Streptococcus faecalis to Lactobacillus plantarum and was transferred among L. plantarum strains. Streptococcus sanguis Challis was transformed with pAM beta 1 isolated from these transconjugants, and transformants harboring intact pAM beta 1 could conjugate the plasmid back to L. plantarum.

Wino dark matter in light of the AMS-02 2015 data

International Nuclear Information System (INIS)

Ibe, Masahiro; Matsumoto, Shigeki; Yanagida, Tsutomu T.; Shirai, Satoshi

2015-06-01

The AMS-02 collaboration has recently reported the antiproton to proton ratio with improved accuracy. In view of uncertainties of the production and the propagation of the cosmic rays, the observed ratio is still consistent with the secondary astrophysical antiproton to proton ratio. However, it is nonetheless enticing to examine whether the observed spectrum can be explained by a strongly motivated dark matter, the wino dark matter. As we will show, we find that the antiproton flux from the wino annihilation can explain the observed spectrum well for its mass range 2.5-3 TeV. The fit to data becomes particularly well compared to the case without the annihilation for the thermal wino dark matter case with a mass about 3 TeV. The ratio is predicted to be quickly decreased at the energy several hundreds of GeV, if this possibility is true, and it will be confirmed or ruled out in near future when the AMS-02 experiment accumulates enough data at this higher energy region.

The testing-effect under investigation. Experiences in Kiel

NARCIS (Netherlands)

Dirkx, Kim; Kester, Liesbeth; Kirschner, Paul A.

2013-01-01

Dirkx, K. J. H., Kester, L., & Kirschner, P. A. (2013, 22 January). The testing-effect under investigation. Experiences in Kiel. Presentation held at the Learning & Cognition meeting, Heerlen, The Netherlands.

Study of the properties of the Am-O system in view of the transmutation of Am 241 in fast reactors; Etude des proprietes du systeme Am-O en vue de la transmutation de l`americium 241 en reacteur a neutrons rapides

Energy Technology Data Exchange (ETDEWEB)

Casalta, S

1996-04-01

To reduce the long term toxicity of Am 241 it was considered to transmute this isotope in fast reactor. The first part of this thesis is an introduction at this problem. In the second part we give the experimental techniques used for the realisation of an AmO{sub 2}-MgO target (powder metallurgy under inert, oxidizing or reducing atmosphere). The properties of the Am-O system has been analyzed by X diffraction, thermodynamic and ceramography, in the Am{sub 2}O{sub 3}-AmO{sub 2} field. In the third part we study the external exposure risk created by the manufacturing of this target and in the last part the behavior of this target in a fast reactor. 66 refs., 28 figs., 25 tabs., 1 append.

Climate Literacy: Progress in AMS Climate Studies Undergraduate Course in Meteorology Program at Jackson State University

Science.gov (United States)

Reddy, S. R.

2013-12-01

AMS Climate Studies is an introductory college-level course developed by the American Meteorological Society for implementation at undergraduate institutions nationwide and increasing involvement of under-represented groups The course places students in a dynamic and highly motivational educational environment where they investigate Earth's climate system using real-world environmental data. The AMS Climate Studies course package consists of a textbook, investigations manual, course website, and course management system-compatible files. Instructors can use these resources in combinations that make for an exciting learning experience for their students. The AMS Climate Studies Diversity Project Workshop participation is on a first-come, first-serve basis as determined by the date-of-receipt of the License Order Form. To grow AMS Diversity Programs to their fullest extent, institutions are encouraged to nominate course instructors who did not previously attend Diversity Project workshops. Until three months before the workshop, two-thirds of the workshop positions would be reserved for institutions new to AMS Diversity Projects. The AMS five day course implementation workshop was held in Washington, DC, during May 24-29, 2012. It covered essential course topics in climate science and global climate change, and strategies for course implementation. Talks would feature climate science and sustainability experts from Federal agencies and area research institutions, such as NASA, NOAA, University of Maryland, Howard University, George Mason University, and other Washington, DC, area institutions. The workshop would also include visits to NASA Goddard Space Flight Center and NOAA's Climate Prediction Center. JSU Meteorology Program will be offering AMS Climate Studies undergraduate course under MET 210: Climatology in spring 2014. AMS Climate Studies is offered as a 3 credit hour laboratory course with 2 lectures and 1 lab sessions per week. Although this course places

AM-37 and ST-36 Are Small Molecule Bombesin Receptor Antagonists.

Science.gov (United States)

Moody, Terry W; Tashakkori, Nicole; Mantey, Samuel A; Moreno, Paola; Ramos-Alvarez, Irene; Leopoldo, Marcello; Jensen, Robert T

2017-01-01

While peptide antagonists for the gastrin-releasing peptide receptor (BB 2 R), neuromedin B receptor (BB 1 R), and bombesin (BB) receptor subtype-3 (BRS-3) exist, there is a need to develop non-peptide small molecule inhibitors for all three BBR. The BB agonist (BA)1 binds with high affinity to the BB 1 R, BB 2 R, and BRS-3. In this communication, small molecule BBR antagonists were evaluated using human lung cancer cells. AM-37 and ST-36 inhibited binding to human BB 1 R, BB 2 R, and BRS-3 with similar affinity ( K i = 1.4-10.8 µM). AM-13 and AM-14 were approximately an order of magnitude less potent than AM-37 and ST-36. The ability of BA1 to elevate cytosolic Ca 2+ in human lung cancer cells transfected with BB 1 R, BB 2 R, and BRS-3 was antagonized by AM-37 and ST-36. BA1 increased tyrosine phosphorylation of the EGFR and ERK in lung cancer cells, which was blocked by AM-37 and ST-36. AM-37 and ST-36 reduced the growth of lung cancer cells that have BBR. The results indicate that AM-37 and ST-36 function as small molecule BB receptor antagonists.

Applications of 14C - AMS on Archaeology, Climate, Environment, Geology, Oceanography and Biology

International Nuclear Information System (INIS)

Gomes, P. R. S.; Macario, K. D.; Anjos, R. M.

2007-01-01

In this contribution we describe several experiments on 14 C-AMS (Accelerator Mass Spectrometry) related to historical, ecological and environmental questions. We discuss the chronology of prehistoric settlements of the central-south Brazilian coast. The unexpected result pulls back by some two thousand years the antiquity consensually accepted for the settlement of that region. We performed an experiment concerning the isotopic signature of the local waters of an important Brazilian coastal upwelling. The results of 14 C-AMS measurements in seaweed tissue show differences in the isotopic signature of the water sources. The present results contribute to opening new perspectives for the use of 14 C as a tracer of the biological production in upwelling areas all over the world. We performed experiments on climate at the Amazon region. At remote lakes of the Amazon region, the Hg accumulation rate archived in sediment cores is a powerful tool for the interpretation of the paleoclimatology and paleoecology of the region. Different sedimentation regimes are observed from ∼41500 yr. BP to the present. The understanding of sea-level fluctuations are fundamental for human occupation of littoral areas and hydrocarbon industry on offshore exploration. We performed radiocarbon dating of foraminifera shell samples, collected in upper slope of Campos Basin, in Southern Brazil. The mean accumulation ratio for the whole column is 6.17 cm/1000 years. Fluctuations in this mean values indicate that the ocean bottom dynamics has some variation during the period. (Author)

Combination of e+/e- ratio from AMS-02 and gamma ray line from Fermi-LAT with implication for Dark Matter

OpenAIRE

Li, Shiyuan; Luo, Yonggang

2013-01-01

The precise AMS-02 data provide definite information for the e+/e- ratio in 100 - 350 GeV region. Assuming that the recent gamma ray line observed by Fermi-LAT experiment is product of dark matter in space and taken as input. We make a global fit for the AMS-02 e+/e- spectrum with both dark matter and pulsar contribution. For this spectrum over 130 GeV, pulsar is the dominant contribution. We also investigate the constrains on hadron production from dark matter annihilation.

Most experiments done so far with limited plants. Large-scale testing ...

Indian Academy of Sciences (India)

First page Back Continue Last page Graphics. Most experiments done so far with limited plants. Large-scale testing needs to be done with objectives such as: Apart from primary transformants, their progenies must be tested. Experiments on segregation, production of homozygous lines, analysis of expression levels in ...

239Pu and 241Am contamination of small vertebrates in NAEG study areas of NTS and TTR

International Nuclear Information System (INIS)

Moor, K.S.; Naele, S.R.; Bradley, W.G.

1977-01-01

Ecological studies of small vertebrates in three plutonium (Pu) contaminated study areas of Nevada Test Site began in Spring, 1972, and were expanded to include four areas of Tonopah Test Range in Fall, 1973. This report consists primarily of presentation and analysis of radioanalytical data on rodents and lizards from Area 11-C, Nevada Test Site. In addition, methodology and preliminary results of initial hematologic studies are presented. Dipodomys microps is a dominant rodent species in all study areas. Concentrations of 239 Pu and 241 Am in pelt, GI tract, and carcass of 74 resident D. microps from five study areas were determined. The only consistent trend evident was that carcass burdens were lower than pelt or GI tract burdens by a factor of 10 2 . Mean ratios of Pu/Am in tissue aliquots were variable, and many were significantly different than ratios in soil or vegetation samples

Operational status of the JAEA-MUTSU tandetron AMS 2008-2009

International Nuclear Information System (INIS)

Kabuto, Shoji; Kinoshita, Naoki; Tanaka, Takayuki; Yamamoto, Nobuo

2010-01-01

A Tandetron Accelerator Mass Spectrometer (AMS) manufactured by High Voltage Engineering Europa in Netherlands had been set up at the Mutsu office of Aomori Research and Development Center, Japan Atomic Energy Agency (JAEA) in 1997. This AMS features 3MV Tandetron accelerator and two independence beamlines for 14 C and 129 I measurement. This AMS has measured both internal and external JAEA researcher's samples based on an open door policy since April 2006. Furthermore, the total operation time of this AMS from the routine operation started exceeds more than 20,000 hours in this year. In this report, we describe not only the summary of the current status and troubles from the previous symposium but also the upgrading of the operation system in this AMS which is carried out from June to July in 2009. (author)

Am5-HT7: molecular and pharmacological characterization of the first serotonin receptor of the honeybee (Apis mellifera).

Science.gov (United States)

Schlenstedt, Jana; Balfanz, Sabine; Baumann, Arnd; Blenau, Wolfgang

2006-09-01

The biogenic amine serotonin (5-HT) plays a key role in the regulation and modulation of many physiological and behavioural processes in both vertebrates and invertebrates. These functions are mediated through the binding of serotonin to its receptors, of which 13 subtypes have been characterized in vertebrates. We have isolated a cDNA from the honeybee Apis mellifera (Am5-ht7) sharing high similarity to members of the 5-HT(7) receptor family. Expression of the Am5-HT(7) receptor in HEK293 cells results in an increase in basal cAMP levels, suggesting that Am5-HT(7) is expressed as a constitutively active receptor. Serotonin application to Am5-ht7-transfected cells elevates cyclic adenosine 3',5'-monophosphate (cAMP) levels in a dose-dependent manner (EC(50) = 1.1-1.8 nm). The Am5-HT(7) receptor is also activated by 5-carboxamidotryptamine, whereas methiothepin acts as an inverse agonist. Receptor expression has been investigated by RT-PCR, in situ hybridization, and western blotting experiments. Receptor mRNA is expressed in the perikarya of various brain neuropils, including intrinsic mushroom body neurons, and in peripheral organs. This study marks the first comprehensive characterization of a serotonin receptor in the honeybee and should facilitate further analysis of the role(s) of the receptor in mediating the various central and peripheral effects of 5-HT.

The Nuclear Security Science and Policy Institute at Texas A&M University

Directory of Open Access Journals (Sweden)

Claudio A. Gariazzo

2015-07-01

Full Text Available The Nuclear Security Science and Policy Institute (NSSPI is a multidisciplinary organization at Texas A&M University and was the first U.S. academic institution focused on technical graduate education, research, and service related to the safeguarding of nuclear materials and the reduction of nuclear threats. NSSPI employs science, engineering, and policy expertise to: (1 conduct research and development to help detect, prevent, and reverse nuclear and radiological proliferation and guard against nuclear terrorism; (2 educate the next generation of nuclear security and nuclear nonproliferation leaders; (3 analyze the interrelationships between policy and technology in the field of nuclear security; and (4 serve as a public resource for knowledge and skills to reduce nuclear threats. Since 2006, over 31 Doctoral and 73 Master degrees were awarded through NSSPI-sponsored research. Forty-one of those degrees are Master of Science in Nuclear Engineering with a specialization in Nuclear Nonproliferation and 16 were Doctorate of Philosophy degrees with a specific focus on nuclear nonproliferation. Over 200 students from both technical and policy backgrounds have taken classes provided by NSSPI at Texas A&M. The model for creating safeguards and security experts, which has in large part been replicated worldwide, was established at Texas A&M by NSSPI faculty and staff. In addition to conventional classroom lectures, NSSPI faculty have provided practical experiences; advised students on valuable research projects that have contributed substantially to the overall nuclear nonproliferation, safeguards and security arenas; and engaged several similar academic and research institutes around the world in activities and research for the benefit of Texas A&M students. NSSPI has had an enormous impact on the nuclear nonproliferation workforce (across the international community in the past 8 years, and this paper is an attempt to summarize the activities

Initial acceptance test experience with FFTF plant equipment

International Nuclear Information System (INIS)

Brown, R.K.; Coleman, K.A.; Mahaffey, M.K.; McCargar, C.G.; Young, M.W.

1978-09-01

The purpose of this paper is to examine the initial acceptance test experience of certain pieces of auxiliary equipment of the Fast Flux Test Facility (FFTF). The scope focuses on the DHX blowers and drive train, inert gas blowers, H and V containment isolation valves, and the Surveillance and In-service Inspection (SISI) transporter and trolley. For each type of equipment, the discussion includes a summary of the design and system function, installation history, preoperational acceptance testing procedures and results, and unusual events and resolutions

The new LLNL AMS sample changer

International Nuclear Information System (INIS)

Roberts, M.L.; Norman, P.J.; Garibaldi, J.L.; Hornady, R.S.

1993-01-01

The Center for Accelerator Mass Spectrometry at LLNL has installed a new 64 position AMS sample changer on our spectrometer. This new sample changer has the capability of being controlled manually by an operator or automatically by the AMS data acquisition computer. Automatic control of the sample changer by the data acquisition system is a necessary step towards unattended AMS operation in our laboratory. The sample changer uses a fiber optic shaft encoder for rough rotational indexing of the sample wheel and a series of sequenced pneumatic cylinders for final mechanical indexing of the wheel and insertion and retraction of samples. Transit time from sample to sample varies from 4 s to 19 s, depending on distance moved. Final sample location can be set to within 50 microns on the x and y axis and within 100 microns in the z axis. Changing sample wheels on the new sample changer is also easier and faster than was possible on our previous sample changer and does not require the use of any tools

Biosorption of Am-241 and Cs-137 by radioactive liquid waste by coffee husk

International Nuclear Information System (INIS)

Ferreira, Rafael Vicente de Padua; Sakata, Solange Kazumi; Bellini, Maria Helena; Marumo, Julio Takehiro

2011-01-01

Radioactive Waste Management Laboratory of Nuclear and Energy Research Institute, IPEN-CNEN/SP, has stored many types of radioactive liquid wastes, including liquid scintillators, mixed wastes from chemical analysis and spent decontamination solutions. These wastes need special attention, because the available treatment processes are often expensive and difficult to manage. Biosorption using biomass of vegetable using agricultural waste has become a very attractive technique because it involves the removal of heavy metals ions by low cost biossorbents. The aim of this study is to evaluate the potential of the coffee husk to remove Am-241 and Cs-137 from radioactive liquid waste. The coffee husk was tested in two forms, treated and untreated. The chemical treatment of the coffee husk was performed with HNO 3 and NaOH diluted solutions. The results showed that the coffee husk did not showed significant differences in behavior and capacity for biosorption for Am-241 and Cs-137 over time. Coffee husk showed low biosorption capacity for Cs-137, removing only 7.2 ± 1.0% in 4 hours of contact time. For Am-241, the maximum biosorption was 57,5 ± 0.6% in 1 hours. These results suggest that coffee husk in untreated form can be used in the treatment of radioactive waste liquid containing Am-241. (author)

Evaluation of remaining behavior of halogen on the fabrication of MOX pellet containing Am

International Nuclear Information System (INIS)

Ozaki, Yoko; Osaka, Masahiko; Obayashi, Hiroshi; Tanaka, Kenya

2004-11-01

It is important to limit the content of halogen elements, namely fluorine and chlorine that are sources of making cladding material corrode, in nuclear fuel from the viewpoint of quality assurance. The halogen content should be more carefully limited in the MOX fuel containing Americium (Am-MOX), which is fabricated in the Alpha-Gamma Facility (AGF) for irradiation testing to be conducted in the experimental fast reactor JOYO, because fluorine may remain in the sintered pellets owing to a formation of AmF 3 known to have a low vapor pressure and may exceeds the limit of 25 ppm. In this study, a series of experimental determination of halogen element in Am-MOX were performed by a combination method of pyrolysis and ion-chromatography for the purpose of an evaluation of behavior of remaining halogen through the sintering process. Oxygen potential, temperature and time were changed as experimental parameters and their effects on the remaining behavior of halogen were examined. It was confirmed that good pellets, which contained small amount of halogen, could be obtained by the sintering for 3 hour at 1700degC in the oxygen potential range from -520 to -390 kJ/mol. In order to analysis of fluorine chemical form in green pellet, thermal analysis was performed. AmF 3 and PuF 3 have been confirmed to remain in the green pellet. (author)

14C-AMS at the Leibniz-Labor: radiometric dating and isotope research

International Nuclear Information System (INIS)

Grootes, Pieter M.; Nadeau, Marie-Josee; Rieck, Anke

2004-01-01

The Leibniz-Labor was founded to provide radiometric dating services using AMS and measured over 15 000 samples and 26 800 targets up to September 2002. Research and development have primarily been directed at improving the efficiency and reliability of AMS measurements, optimising existing sample preparation procedures for AMS and developing new ones. The standard chemical pre-treatment of organic radiocarbon samples produces often two fractions: one from which contaminants have been removed, and one in which they have been enriched. Dating both fractions reveals the degree of sample contamination. This provides a useful indication of the reliability of the sample age obtained and of the environmental conditions where the sample was taken. Upgrades to reduce maintenance include replacing four cryo- by turbo pumps, installing a deionizer loop, which keeps conductivity between 100 and 150 μS/cm to control corrosion, in the closed cooling water circuit, and developing a new sample wheel, which holds target holders with a groove and spring clip. Long term stability is demonstrated by the results obtained for IAEA reference materials, measured routinely and regularly over the years. Tests made as part of the FIRI project demonstrate that reliable measurements down to <0.1 mg C can be made

AMS-11 in Rome, 2008: Past achievements, current and future trends

International Nuclear Information System (INIS)

Fink, David

2010-01-01

The volume of scientific work and achievements of the international Accelerator Mass Spectrometry community over the past 30 years is presented by quantifying the annual increases in past AMS conference participation, trends in technical developments and applications, the rate of growth of new AMS facilities, sample throughput, publications and general scientific impact. Also a brief summary with some highlights of the International AMS-11 Rome Conference is presented with some flavour of current trends and future directions in AMS.

Design and construction of a Wien velocity filter for AMS facilities

CERN Document Server

Catana, D; Enachescu, M; Plostinaru, V D; Vata, I; Rohrer, L

2001-01-01

Many experiments in atomic and nuclear physics using accelerated particles require accurate ion beams with respect to their atomic number, mass number and ion charge. These requirements have special important for experiments of accelerated mass spectrometry. Double focussing analyzing magnets perform the mass selection of charged ions. However, the magnetic analyzer cannot distinguish between particles with equal charge and having the same mass-velocity product. A simple way of resolving this degeneracy is to use a Wien velocity filter, WVF, in conjunction with the magnet analyzers. The design and construction of a WVF is presented together with experiments performed to determine the separation power. A velocity separation DELTA v/v = 1/100 was obtained. The design in this separate arrangements of fields is simple and straightforward. The construction can be achieved in a usual workshop. The applications of the WVF are manifold, e.g., AMS, ERDA, RBS, etc. (authors)

Design and construction of a Wien velocity filter for AMS facilities

International Nuclear Information System (INIS)

Catana, D.; Stan-Sion, C.; Enachescu, M.; Plostinaru, D.; Vata, I.; Rohrer, L.

2001-01-01

Many experiments in atomic and nuclear physics using accelerated particles require accurate ion beams with respect to their atomic number, mass number and ion charge. These requirements have special important for experiments of accelerated mass spectrometry. Double focussing analyzing magnets perform the mass selection of charged ions. However, the magnetic analyzer cannot distinguish between particles with equal charge and having the same mass-velocity product. A simple way of resolving this degeneracy is to use a Wien velocity filter, WVF, in conjunction with the magnet analyzers. The design and construction of a WVF is presented together with experiments performed to determine the separation power. A velocity separation Δv/v = 1/100 was obtained. The design in this separate arrangements of fields is simple and straightforward. The construction can be achieved in a usual workshop. The applications of the WVF are manifold, e.g., AMS, ERDA, RBS, etc. (authors)

América Latina marginada

Directory of Open Access Journals (Sweden)

Tito Drago

2015-01-01

Full Text Available La renovación en los países comunistas atrae la atención, el comercio, las inversiones y la ayuda de Estados Unidos, Japón y Europa Occidental. En una primera etapa, ello incidirá negativamente en las relaciones de ese continente con América Latina, es creciente y está en pleno proceso acelerado, la marginación del comercio exterior de la Comunidad Europea. Las inversiones directas no presentan perspectivas. Asegura que a esto se suma la invasión a Panamá, que fue interpretada como que las potencias llegaron a acuerdos en Malta para el reparto del mundo.Con la perestroika la situación de América Latina desmejoró notablemente.

Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01

CERN Document Server

Aguilar, M; Allaby, James V; Alpat, B; Ambrosi, G; Anderhub, H; Ao, L; Arefev, A; Azzarello, P; Baldini, L; Basile, M; Barancourt, D; Barão, F; Barbier, G; Barreira, G; Battiston, R; Becker, R; Becker, U; Bellagamba, L; Bene, P; Berdugo, J; Berges, P; Bertucci, B; Biland, A; Blasko, S; Bölla, G; Boschini, M; Bourquin, M; Brocco, L; Bruni, G; Buénerd, M; Burger, J D; Burger, W J; Cai, X D; Camps, C; Cannarsa, P; Capell, M; Cardano, F; Casadei, D; Casaus, J; Castellini, G; Chang, Y H; Chen, H F; Chen, H S; Chen, Z G; Chernoplekov, N A; Tzi Hong Chiueh; Cho, K; Choi, M J; Choi, Y Y; Cindolo, F; Commichau, V; Contin, A; Cortina, E; Cristinziani, M; Dai, T S; Delgado, C; Difalco, S; Djambazov, L; D'Antone, I; Dong, Z R; Emonet, P; Engelberg, J; Eppling, F J; Eronen, T; Esposito, G; Extermann, P; Favier, Jean; Fiandrini, E; Fisher, P H; Flügge, G; Fouque, N; Galaktionov, Yu; Gast, H; Gervasi, M; Giusti, P; Grandi, D; Grimm, O; Gu, W Q; Hangarter, K; Hasan, A; Hermel, V; Hofer, H; Hungerford, W; Jongmanns, M; Karlamaa, K; Karpinski, W; Kenney, G; Kim, D H; Kim, G N; Kim, K S; Kim, M Y; Klimentov, A; Kossakowski, R; Kounine, A; Koutsenko, V F; Kraeber, M; Laborie, G; Laitinen, T; Lamanna, G; Lanciotti, E; Laurenti, G; Lebedev, A; Lechanoine-Leluc, C; Lee, M W; Lee, S C; Levi, G; Liu, C L; Liu, H T; Lu, G; Lü, Y S; Lübelsmeyer, K; Luckey, D; Lustermann, W; Maña, C; Margotti, A; Mayet, F; McNeil, R R; Meillon, B; Menichelli, M; Mihul, A; Mujunen, A; Oliva, A; Olzem, J; Palmonari, F; Park, H B; Park, W H; Pauluzzi, M; Pauss, F; Perrin, E; Pesci, A; Pevsner, A; Pilo, F; Pimenta, M; Plyaskin, V; Pozhidaev, V; Pohl, M; Produit, N; Rancoita, P G; Rapin, D; Raupach, F; Ren, D; Ren, Z; Ribordy, M; Richeux, J P; Riihonen, E; Ritakari, J; Ro, S; Röser, U; Rossin, C; Sagdeev, R; Santos, D; Sartorelli, G; Sbarra, C; Schael, S; Schultzvon Dratzig, A; Schwering, G; Seo, E S; Shin, J W; Shoumilov, E; Shoutko, V; Siedenburg, T; Siedling, R; Son, D; Song, T; Spinella, F; Steuer, M; Sun, G S; Suter, H; Tang, X W; Ting, Samuel C C; Ting, S M; Tornikoski, M; Torsti, J; Trumper, J; Ulbricht, J; Urpo, S; Valtonen, E; Vandenhirtz, J; Velikhov, E P; Verlaat, B; Vetlitskii, I; Vezzu, F; Vialle, J P; Viertel, G; Vite, D; Von Gunten, H; Waldmeier-Wicki, S; Wallraff, W; Wang, B C; Wang, J Z; Wiik, K; Williams, C; Wu, S X; Xia, P C; Xu, S; Yan, J L; Yan, L G; Yang, C G; Yang, J; Yang, M; Ye, S W; Xu, Z Z; Zhang, H Y; Zhang, Z P; Zhao, D X; Zhou, Y; Zhu, G Y; Zhu, W Z; Zhuang, H L; Zichichi, A; Zimmermann, B; Zuccon, P

2007-01-01

A measurement of the cosmic ray positron fraction e+/(e+ + e-) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 10^6 is reached by identifying converted bremsstrahlung photons emitted from positrons.

Cosmic-ray positron fraction measurement from 1 to 30 GeV with AMS-01

International Nuclear Information System (INIS)

Aguilar, M.; Alcaraz, J.; Allaby, J.

2007-01-01

A measurement of the cosmic ray positron fraction e + /(e + +e - ) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton background suppression on the order of 10 6 is reached by identifying converted bremsstrahlung photons emitted from positrons

Design of a materials testing experiment for the INTOR

International Nuclear Information System (INIS)

Vogel, M.A.; Opperman, E.K.

1981-01-01

The United States, Japan, USSR and the European community are jointly participating in the design of an International Tokamak Reactor called INTOR. In support of the US contribution to the INTOR design, the features of an experiment for bulk neutron irradiation damage studies were developed. It is anticipated that materials testing will be an important part of the programmatic mission of INTOR and consequently the requirements for materials testing in INTOR must be identified early in the reactor design to insure compatibility. The design features of the experiment, called a Channel Test, are given in this paper. The major components of the channel test are the water cooled heat sink (channel module) and the specimen capsule. The temperature within each of the 153 specimen capsules is predetermined by engineering the thermal barrier between the specimen capsule and heat sink. Individual capsules can be independently accessed and are designed to operate at a predetermined temperature within the range of 50 to 700 0 C. The total irradiation volume within a single channel test is 45 liters. Features of the channel test that result in experimental versatility and simplified remote access and handling are discussed

Presymptomatic ALS genetic counseling and testing: Experience and recommendations.

Science.gov (United States)

Benatar, Michael; Stanislaw, Christine; Reyes, Eliana; Hussain, Sumaira; Cooley, Anne; Fernandez, Maria Catalina; Dauphin, Danielle D; Michon, Sara-Claude; Andersen, Peter M; Wuu, Joanne

2016-06-14

Remarkable advances in our understanding of the genetic contributions to amyotrophic lateral sclerosis (ALS) have sparked discussion and debate about whether clinical genetic testing should routinely be offered to patients with ALS. A related, but distinct, question is whether presymptomatic genetic testing should be offered to family members who may be at risk for developing ALS. Existing guidelines for presymptomatic counseling and testing are mostly based on small number of individuals, clinical judgment, and experience from other neurodegenerative disorders. Over the course of the last 8 years, we have provided testing and 317 genetic counseling sessions (including predecision, pretest, posttest, and ad hoc counseling) to 161 first-degree family members participating in the Pre-Symptomatic Familial ALS Study (Pre-fALS), as well as testing and 75 posttest counseling sessions to 63 individuals with familial ALS. Based on this experience, and the real-world challenges we have had to overcome in the process, we recommend an updated set of guidelines for providing presymptomatic genetic counseling and testing to people at high genetic risk for developing ALS. These recommendations are especially timely and relevant given the growing interest in studying presymptomatic ALS. © 2016 American Academy of Neurology.

BellTest and CHSH experiments with more than two settings

Energy Technology Data Exchange (ETDEWEB)

Basoalto, R M; Percival, I C [Department of Physics, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom)

2003-07-04

Strong nonlocality allows signals faster than light. Weak nonlocality is a statistical property of classical events for which there is no realistic local theory. This requires the violation of at least one general Bell inequality. The theory of ideal quantum measurements predicts weak nonlocality but not strong nonlocality. Bell experiment here refers to any experiment designed to demonstrate weak nonlocality. BellTest is a computer program generally available on the Web to help planning and analysis of such Bell experiments. In Mode 1 it obtains general Bell inequalities. In Mode 2 it tests for their violation. We describe its use, with some new results for illustration.

Status of AMS at the China Institute of Atomic Energy

International Nuclear Information System (INIS)

Jiang Shan; He Ming; Hu Yueming; Yuan Jian

2007-01-01

The first accelerator mass spectrometry (AMS) system in China was set up at the China Institute of Atomic Energy in 1989. In the following years, long-lived nuclides 10 Be, 26 Al, 36 Cl, 41 Ca, 79 Se and 129 I were measured in geology, environment and biology samples. The newly development of the AMS measurement and applications in recent years were introduced. The current projects include upgrading of AMS injection system for increasing mass resolution, new particle identification techniques for separation of isobars, development of the AMS measurement methods for 99 Tc, 93 Zr, 151 Sm and 182 Hf analyses, and applications in biology, environment and nuclear astrophysics. (authors)

AM-37 and ST-36 Are Small Molecule Bombesin Receptor Antagonists

Directory of Open Access Journals (Sweden)

Terry W. Moody

2017-07-01

Full Text Available While peptide antagonists for the gastrin-releasing peptide receptor (BB2R, neuromedin B receptor (BB1R, and bombesin (BB receptor subtype-3 (BRS-3 exist, there is a need to develop non-peptide small molecule inhibitors for all three BBR. The BB agonist (BA1 binds with high affinity to the BB1R, BB2R, and BRS-3. In this communication, small molecule BBR antagonists were evaluated using human lung cancer cells. AM-37 and ST-36 inhibited binding to human BB1R, BB2R, and BRS-3 with similar affinity (Ki = 1.4–10.8 µM. AM-13 and AM-14 were approximately an order of magnitude less potent than AM-37 and ST-36. The ability of BA1 to elevate cytosolic Ca2+ in human lung cancer cells transfected with BB1R, BB2R, and BRS-3 was antagonized by AM-37 and ST-36. BA1 increased tyrosine phosphorylation of the EGFR and ERK in lung cancer cells, which was blocked by AM-37 and ST-36. AM-37 and ST-36 reduced the growth of lung cancer cells that have BBR. The results indicate that AM-37 and ST-36 function as small molecule BB receptor antagonists.

AM-37 and ST-36 Are Small Molecule Bombesin Receptor Antagonists

Science.gov (United States)

Moody, Terry W.; Tashakkori, Nicole; Mantey, Samuel A.; Moreno, Paola; Ramos-Alvarez, Irene; Leopoldo, Marcello; Jensen, Robert T.

2017-01-01

While peptide antagonists for the gastrin-releasing peptide receptor (BB2R), neuromedin B receptor (BB1R), and bombesin (BB) receptor subtype-3 (BRS-3) exist, there is a need to develop non-peptide small molecule inhibitors for all three BBR. The BB agonist (BA)1 binds with high affinity to the BB1R, BB2R, and BRS-3. In this communication, small molecule BBR antagonists were evaluated using human lung cancer cells. AM-37 and ST-36 inhibited binding to human BB1R, BB2R, and BRS-3 with similar affinity (Ki = 1.4–10.8 µM). AM-13 and AM-14 were approximately an order of magnitude less potent than AM-37 and ST-36. The ability of BA1 to elevate cytosolic Ca2+ in human lung cancer cells transfected with BB1R, BB2R, and BRS-3 was antagonized by AM-37 and ST-36. BA1 increased tyrosine phosphorylation of the EGFR and ERK in lung cancer cells, which was blocked by AM-37 and ST-36. AM-37 and ST-36 reduced the growth of lung cancer cells that have BBR. The results indicate that AM-37 and ST-36 function as small molecule BB receptor antagonists. PMID:28785244

Decorporation of 241Am in beagles by DTPA

International Nuclear Information System (INIS)

Lloyd, R.D.; McFarland, S.S.; Taylor, G.N.; Williams, J.L.; Mays, C.W.

1975-01-01

Chelation treatments using daily subcutaneous injections of ZnNa 3 -DTPA were begun 2 wk after the intravenous administration of 0.3 μCi/kg 241 Am citrate to six female beagles averaging 505 days of age. Retention of americium in the liver and in non-liver tissue (mainly skeleton) was followed serially in the living dogs by a combination of total-body and partial-body counting. During the first 13 mo of DTPA therapy, the removal of 241 Am from two dogs given one DTPA injection each day of 0.027 or 0.034 mmole/kg was similar to the fraction removed from two other dogs given a similar total of 0.035 or 0.037 mmole/kg/day in five fractionated injections each day. Increasing the daily amount of DTPA to 0.36 and 5.0 mmole/kg/day in the two remaining dogs only slightly increased the removal of 241 Am. At the beginning of chelation therapy, all six dogs averaged 43 percent of the injected 241 Am in the liver and 46 percent in nonliver tissue. 241 Am retention in liver at 2 mo of therapy was about 2 percent of pretreatment liver retention, decreased to roughly 1 percent of pretreatment retention by 5 mo of DTPA administration, and was undetectable at 13 months. Nonliver retention at 2 mo was 53 percent of pretreatment retention in nonliver tissue, at 5 mo averaged about 40 percent, and had decreased to 27 percent of pretreatment values by 13 mo of chelation therapy. In contrast, for beagles of our colony not treated with DTPA, 241 Am in the liver and in nonliver tissue exhibited a biological half-time in the order of 10 yr. (U.S.)

Determining DfT Hardware by VHDL-AMS Fault Simulation for Biological Micro-Electronic Fluidic Arrays

NARCIS (Netherlands)

Kerkhoff, Hans G.; Zhang, X.; Liu, H.; Richardson, A.; Nouet, P.; Azais, F.

2005-01-01

The interest of microelectronic fluidic arrays for biomedical applications, like DNA determination, is rapidly increasing. In order to evaluate these systems in terms of required Design-for-Test structures, fault simulations in both fluidic and electronic domains are necessary. VHDL-AMS can be used

The Formation Mechanism and Corrosion Resistance of a Composite Phosphate Conversion Film on AM60 Alloy.

Science.gov (United States)

Chen, Jun; Lan, Xiangna; Wang, Chao; Zhang, Qinyong

2018-03-08

Magnesium alloy AM60 has high duc and toughness, which is expected to increase in demand for automotive applications. However, it is too active, and coatings have been extensively studied to prevent corrosion. In this work, a Ba-containing composite phosphate film has been prepared on the surface of AM60. The composition and formation mechanism of the film have been investigated using a scanning electronic microscope equipped with energy dispersive X-ray spectroscopy, Fourier transform infrared, X-ray photoelectron spectroscopy, and X-ray diffractometry tests. The corrosion resistance of the film has been measured by electrochemical and immersion tests. The results show that the deposition film has fully covered the substrate but there are some micro-cracks. The structure of the film is complex, and consists of MgHPO₄·3H₂O, MnHPO₄·2.25H₂O, BaHPO₄·3H₂O, BaMg₂(PO₄)₂, Mg₃(PO₄)₂·22H₂O, Ca₃(PO₄)₂·xH₂O, and some amorphous phases. The composite phosphate film has better anticorrosion performance than the AM60 and can protect the bare alloy from corrosion for more than 12 h in 0.6 M NaCl.

Recent 210Pb, 137Cs and 241Am accumulation in an ombrotrophic peatland from Amsterdam Island (Southern Indian Ocean).

Science.gov (United States)

Li, Chuxian; Le Roux, Gaël; Sonke, Jeroen; van Beek, Pieter; Souhaut, Marc; Van der Putten, Nathalie; De Vleeschouwer, François

2017-09-01

Over the past 50 years, 210 Pb, 137 Cs and 241 Am have been abundantly used in reconstructing recent sediment and peat chronologies. The study of global aerosol-climate interaction is also partially depending on our understanding of 222 Rn- 210 Pb cycling, as radionuclides are useful aerosol tracers. However, in comparison with the Northern Hemisphere, few data are available for these radionuclides in the Southern Hemisphere, especially in the South Indian Ocean. A peat core was collected in an ombrotrophic peatland from the remote Amsterdam Island (AMS) and was analyzed for 210 Pb, 137 Cs and 241 Am radionuclides using an underground ultra-low background gamma spectrometer. The 210 Pb Constant Rate of Supply (CRS) model of peat accumulations is validated by peaks of artificial radionuclides ( 137 Cs and 241 Am) that are related to nuclear weapon tests. We compared the AMS 210 Pb data with an updated 210 Pb deposition database. The 210 Pb flux of 98 ± 6 Bq·m -2 ·y -1 derived from the AMS core agrees with data from Madagascar and South Africa. The elevated flux observed at such a remote location may result from the enhanced 222 Rn activity and frequent rainfall in AMS. This enhanced 222 Rn activity itself may be explained by continental air masses passing over southern Africa and/or Madagascar. The 210 Pb flux at AMS is higher than those derived from cores collected in coastal areas in Argentina and Chile, which are areas dominated by marine westerly winds with low 222 Rn activities. We report a 137 Cs inventory at AMS of 144 ± 13 Bq·m -2 (corrected to 1969). Our data thus contribute to the under-represented data coverage in the mid-latitudes of the Southern Hemisphere. Copyright © 2017 Elsevier Ltd. All rights reserved.

Extraction Chromatography for Am and Cm Recovery in Engineering Scale

International Nuclear Information System (INIS)

Koma, Y.; Watanabe, S.; Sano, Y.; Asakura, T.; Morita, Y.

2008-01-01

The Japan Atomic Energy Agency (JAEA) has been developing the extraction chromatography for Am and Cm (An(III)) recovery from HLLW aiming at an engineering scale application. For process development, we started to assess the characteristics of adsorbents with some extractants by laboratory scale experiments. The experimental results with HDEHP/SiO 2 -P adsorbent suggested that An(III) is separated from other fission products by adjusting the pH of a feed solution and/or an eluent containing DTPA to be an appropriate value. The durability of CMPO/SiO 2 -P and HDEHP/SiO 2 -P adsorbents for gamma-ray irradiation were estimated to be 1 and 0.5 MGy, respectively. In the system development, system experiments for fluid flow, safety and durability using engineering scale column as well as studies on remote control/maintenance are now under progress. (authors)

36Cl-AMS measurements with 3-MV tandem accelerator

International Nuclear Information System (INIS)

Wang Huijuan; Guan Yongjing; Zhang Wei; Jiang Shan; Ming He

2013-01-01

36 C- is one of the most interesting nuclides in accelerator mass spectrometry (AMS) measurements. The application of 36 Cl has been widely applied in various fields. All most all of 36 Cl AMS measurements at natural isotopic concentrations have yet been performed at tandem accelerator with 5 MV or higher terminal voltage. The measure improvement of 36 Cl and other medium heavy isotopes performed at 3 MV in AMS facilities is one of the hottest topics in AMS measurements. In order to increase the suppression factor of 36 S, the energy loss straggling and angular straggling of 36 Cl and 36 S ions in various counter gases (P10, isobutane and propane) were investigated. Some groundwater samples were measured with energy of 32 MeV, and the results were in good agreement with the result obtained with ion energy of 72 MeV. The results indicate that the approximate detection limit of 36 Cl in 3 MV AMS facility is 36 Cl/Cl=1 × 10 -14 , and the uncertainty is 30% when the sample with isotopic ration 36 Cl/Cl≈10 -13 . (authors)

Electronic structure of Pu-Ce(-Ga) and Pu-Am(-Ga) alloys, stabilized in the {delta} phase; Structure electronique d'alliages Pu-Ce(-Ga) et Pu-Am(-Ga) stabilises en phase {delta}

Energy Technology Data Exchange (ETDEWEB)

Dormeval, M

2001-09-01

The behaviour of {delta}-plutonium, stable between 319 and 451 deg C, exhibits numerous singularities which are still a mystery for both physicists and metallurgists. This is due to its complex electronic structure, and in particular to the 5f electrons, which are at the edge between localization and delocalization. The stability domain of the {delta} phase can be extended down to room temperature by alloying with so called 'deltagen atoms' such as gallium (Ga), aluminum (A1), cerium (Ce) or americium (Am). The present work deals, one the one hand, with the influence of cerium and americium solutes regarding the localization of the 5f electrons of {delta}-plutonium, in binary Pu-Ce and Pu-Am alloys. On the other hand, the effect of two different deltagen solutes, simultaneously present, on the stability of the {delta} phase has been studied in ternary Pu-Am-Ga and Pu-Ce-Ga alloys. The electronic structure being strongly related to the crystalline organization, characterization methods such as X-Ray diffraction and EXAFS measurements were used together with electrical resistivity and magnetic susceptibility experiments. These showed that the roles of cerium and americium, supposed to be similar at the beginning of this investigation, are actually very different. Moreover, the additive effect of cerium and gallium, and, americium and gallium, has been demonstrated. Studying plutonium alloys, which are radioactive, also means following their evolution in time. The characteristics of the alloys have then been followed which allowed to detect, in Pu-Ce(-Ga) alloys, a destabilization of the {delta} phase and, to observe, in Pu-Am(-Ga) alloys, the influence of self-irradiation defects on the magnetic response. (author)

AMS. A powerful tool for probing nucleosynthesis via long-lived radionuclides

International Nuclear Information System (INIS)

Wallner, A.; Golser, R.; Kutschera, W.; Priller, A.; Steier, P.; Kaeppeler, F.

2005-01-01

The potential of accelerator mass spectrometry (AMS) will be demonstrated on typical radionuclides of interest with half-lives between some years and up to hundred million years. The Vienna Environmental Research Accelerator (VERA) represents a state-of-the-art AMS facility which provides the ability for quantifying nuclides over the whole mass range. At VERA, AMS is used for quantifying long-lived radionuclides within a wide range of applications - from archaeology to astrophysics. Lack of information on cross section data exists for a list of nuclides pointed out by nuclear data requests. The potential of AMS as a powerful tool for probing nucleosynthesis will be demonstrated by means of some prime examples. Recent developments in the technique of AMS will be highlighted and some applications of AMS in astrophysics will be discussed. In addition, an overview on detection limits, measurement precision as well as the recent measurement program at VERA for quantifying such long-lived radionuclides will be presented. (author)

The Cryogenic Test Bed experiments: Cryogenic heat pipe flight experiment CRYOHP (STS-53). Cryogenic two phase flight experiment CRYOTP (STS-62). Cryogenic flexible diode flight experiment CRYOFD

Science.gov (United States)

Thienel, Lee; Stouffer, Chuck

1995-09-01

This paper presents an overview of the Cryogenic Test Bed (CTB) experiments including experiment results, integration techniques used, and lessons learned during integration, test and flight phases of the Cryogenic Heat Pipe Flight Experiment (STS-53) and the Cryogenic Two Phase Flight Experiment (OAST-2, STS-62). We will also discuss the Cryogenic Flexible Diode Heat Pipe (CRYOFD) experiment which will fly in the 1996/97 time frame and the fourth flight of the CTB which will fly in the 1997/98 time frame. The two missions tested two oxygen axially grooved heat pipes, a nitrogen fibrous wick heat pipe and a 2-methylpentane phase change material thermal storage unit. Techniques were found for solving problems with vibration from the cryo-collers transmitted through the compressors and the cold heads, and mounting the heat pipe without introducing parasitic heat leaks. A thermally conductive interface material was selected that would meet the requirements and perform over the temperature range of 55 to 300 K. Problems are discussed with the bi-metallic thermostats used for heater circuit protection and the S-Glass suspension straps originally used to secure the BETSU PCM in the CRYOTP mission. Flight results will be compared to 1-g test results and differences will be discussed.

Steam line rupture experiments with the PPOOLEX test facility

International Nuclear Information System (INIS)

Laine, J.; Puustinen, M.

2008-07-01

The results of the steam line rupture experiment series in 2007 with the scaled down PPOOLEX test facility designed and constructed at Lappeenranta University of Technology are reported. The test facility is a closed stainless steel vessel divided into two compartments, dry well and wet well. Air was blown into the dry well compartment and from there through a DN200 blowdown pipe to the condensation pool. Altogether five experiments, each consisting of several blows (tests), were carried out. The main purpose of the experiment series was to study the initial phase of a postulated steam line break accident inside a BWR containment. Specifically, thermal stratification in the dry well compartment and ejection of water plug from the blowdown pipe were of interest. In addition, the effect of counterpressure on bubble dynamics was studied. A temperature difference of approximately 15 deg. C between the upper and lower part of the dry well was measured. In the wet well gas space, a temperature difference of more than 30 deg. C was registered. These were measured during the compression period of the tests. Towards the end of the tests the temperature differences tended to disappear. To get a more detailed picture of temperature distribution in the wet well, especially close to the water level, a dense net of measurements is required in future experiments. In longer experiments, heat conduction to structures and heat losses to surroundings should also be taken into account. Ejection of water plugs from the blowdown pipe did not cause notable loads to the structures due to the suppressing effect of the dry well compartment. The maximum measured pressure pulse at the pool bottom was only 10 kPa and the maximum strain amplitude at the pool bottom rounding was negligible both in axial and circumferential direction. As the counterpressure of the system increased, but the flow rate remained the same, the maximum size of the air bubbles at the blowdown pipe outlet got smaller and

Steam line rupture experiments with the PPOOLEX test facility

Energy Technology Data Exchange (ETDEWEB)

Laine, J.; Puustinen, M. (Lappeenranta Univ. of Technology, Nuclear Safety Research Unit (Finland))

2008-07-15

The results of the steam line rupture experiment series in 2007 with the scaled down PPOOLEX test facility designed and constructed at Lappeenranta University of Technology are reported. The test facility is a closed stainless steel vessel divided into two compartments, dry well and wet well. Air was blown into the dry well compartment and from there through a DN200 blowdown pipe to the condensation pool. Altogether five experiments, each consisting of several blows (tests), were carried out. The main purpose of the experiment series was to study the initial phase of a postulated steam line break accident inside a BWR containment. Specifically, thermal stratification in the dry well compartment and ejection of water plug from the blowdown pipe were of interest. In addition, the effect of counterpressure on bubble dynamics was studied. A temperature difference of approximately 15 deg. C between the upper and lower part of the dry well was measured. In the wet well gas space, a temperature difference of more than 30 deg. C was registered. These were measured during the compression period of the tests. Towards the end of the tests the temperature differences tended to disappear. To get a more detailed picture of temperature distribution in the wet well, especially close to the water level, a dense net of measurements is required in future experiments. In longer experiments, heat conduction to structures and heat losses to surroundings should also be taken into account. Ejection of water plugs from the blowdown pipe did not cause notable loads to the structures due to the suppressing effect of the dry well compartment. The maximum measured pressure pulse at the pool bottom was only 10 kPa and the maximum strain amplitude at the pool bottom rounding was negligible both in axial and circumferential direction. As the counterpressure of the system increased, but the flow rate remained the same, the maximum size of the air bubbles at the blowdown pipe outlet got smaller and

Thermodynamic stabilities of MO2+x(s) (M = U, Np, Pu and Am), pourbaix diagrams

International Nuclear Information System (INIS)

Vitorge, Pierre; Faure, Marie-Helene; Vercouter, Thomas; Capdevila, Helene; Maillard, Serge

2002-01-01

The experimental solubilities of the hydrated amorphous freshly precipitated M(OH) z (am) and MO 2 (OH) z (am) compounds are often used as an upper limit for the safety assessments of deep waste repositories, since these compounds slowly transform to less soluble ones, as typically M(OH) 4 (am) to MO 2 (cr). Solubility (vs. redox potential) at pH=8, and E-pH predominance diagrams are plotted in aqueous solutions at 25degC by using thermodynamic data recently selected by the NEA-TDB review, or estimated by using classical chemical analogies for the non-redox reactions. The solubilities and relative stabilities are also calculated for the MO 2+x (s) crystalline compounds of known stabilities: U 4 O 9 (s), U 3 O 7 (s), U 3 O 8 (s) and Np 2 O 5 (s) where 2+x = 2.25, 2.33, 2.67 and 2.5 respectively. The stabilities of the other MO 2+x (s) compounds are estimated by analogy: M 4 O 9 (s) (M=U, Np, Pu), M 3 O 7 (s) and M 3 O 8 (s) (M=U, Pu), and M 2 O 5 (s) (M=Np, Am) are predicted to be more stable (i.e. less soluble), than the amorphous hydroxides. However their precipitation have never been observed at room temperature possibly for kinetic reasons or difficulties in interpreting solubility experiments. (author)

PBF/LOFT Lead Rod Test Program experiment predictions document

International Nuclear Information System (INIS)

Varacalle, D.J.; Cox, W.R.; Niebruegge, D.A.; Seiber, S.J.; Brake, T.E.; Driskell, W.E.; Nigg, D.W.; Tolman, E.L.

1978-12-01

The PBF/LOFT Lead Rod (LLR) Test Program is being conducted to provide experimental information on the behavior of nuclear fuel under normal and accident conditions in the Power Burst Facility (PBF) at the Idaho National Engineering Laboratory. The PBF/LLR tests are designed to simulate the test conditions for the LOFT Power Ascension Tests L2-3 through L2-5. The test program has been designed to provide a parametric evaluation of the LOFT fuel (center and peripheral modules) over a wide range of power. This report presents the experiment predictions for the three four-rod LOCA tests

Test on the reactor with the portable digital reactivity meter for physical experiment

International Nuclear Information System (INIS)

Huang Liyuan

2010-01-01

Test must be performed on the zero power reactor During the development of portable digital reactivity meter for physical experiment, in order to check its measurement function and accuracy. It describes the test facility, test core, test methods, test items and test results. The test results show that the instrument satisfy the requirements of technical specification, and satisfy the reactivity measurement in the physical experiments on reactors. (authors)

IAEA A+M Unit Activities

International Nuclear Information System (INIS)

Braams, B. J.; Chung, H.-K.; Sheikh, K.

2011-01-01

Research on fusion energy devices requires a large amount of data for atomic, molecular and plasma-surface interactions. As current machines are updated and future machines are designed, data for a variety of different materials for a wide range of plasma parameters arise. The Atomic and Molecular (A+M) Data Unit of the International Atomic Energy Agency works to coordinate efforts to establish databases for this fusion research effort. Current activities for database development include a number of Coordinated Research Projects (CRP), Technical Meetings, Consultant Meetings and a number of collaborations. These activities generate significant new data in support of fusion research. These data are published in journals as well as IAEA publications and are included in numerical databases ALADDIN accessible by all fusion researchers. Historically a number of institutions have contributed to development of such databases and continue to participate in a Data Centre Network, supported by the A+M Unit. Members of this network maintain individual databases, many of which can be searched using the GENIE search engine. The A+M Unit host the OPEN-ADAS system that allows access to most of the numerical data stored within the ADAS system. An effort on development of an XML schema for data exchange among the databases is underway. Many numerical data for specific processes in fusion relevant materials are not available. In many cases computer codes exist with the capability of generating such data as needed. An informal network of institutions with such capabilities is in the process of formation to provide a means quickly generating such data. The A+M Unit maintains on-line code capabilities to generate atomic and molecular data and serves as an access point to LANL atomic physics codes and FLYCHK, Non-LTE kinetics codes at NIST. Currently, a wiki-style knowledge base is under the development. It will host a wealth of information on atomic, molecular, plasma-surface data for

Experiment data report for LOFT nonnuclear test L1-3

International Nuclear Information System (INIS)

Millar, G.M.

1977-04-01

Test L1-3 was the third in a series of five nonnuclear isothermal blowdown tests conducted by the Loss of Fluid Test (LOFT) Program. For this test the LOFT Facility was configured to simulate a loss-of-coolant accident in a large pressurized water reactor resulting from a 200 percent double-ended shear break in a cold leg of the primary coolant system. A hydraulic core simulator assembly was installed in place of the nuclear core. The initial conditions in the primary coolant system intact loop were: temperature at 540 0 F, pressure at 2256 psig, and loop flow at 2.34 x 10 6 lbm/hr. During system depressurization, emergency core cooling water was specified to be injected into the lower plenum of the reactor vessel using an accumulator, a low-pressure injection system pump, and a high-pressure injection system pump to provide data on the effects of emergency core cooling on the system thermal-hydraulic response. Injection into the lower plenum was initiated from the high- and low-pressure injection systems. Injection from the accumulator, however, was not initiated because a valve was inadvertently left closed. The experiment, therefore, was not completely successful in that one of the objectives outlined in the experiment operating specification for this test was not accomplished. Test L1-3 was repeated at Test L1-3A to meet the experimental requirements. Despite these difficulties, Test L1-3 did provide very valuable data to verify experiment repeatability

Speciation of Am(III)/Eu(III) sorbed on γ-alumina. Effect of metal ion concentration

International Nuclear Information System (INIS)

Kumar, S.; Tomar, B.S.; Godbole, S.V.

2013-01-01

The present paper describes the speciation of Am(III)/Eu(III) sorbed on γ-alumina, and its evolution with changing metal ion concentration, studied using batch sorption experiment, time resolved fluorescence spectroscopy (TRFS), extended X-ray absorption fine structure (EXAFS) and surface Complexation modeling (SCM). Though numerous studies exist in the literature on the speciation of trivalent actinides and lanthanides on alumina surface, the mechanism of sorption at high metal ion concentrations is not yet fully understood. Batch sorption experiments of Am(III) on γ-alumina under varying condition of pH (3-10), ionic strength (0.005-0.1 M NaClO 4 ) and metal ion concentration (10 -7 -10 -4 M) were performed. Higher metal ion concentration was achieved by the addition of Eu(III) considering it as an analogue of Am(III). Time resolved fluorescence spectroscopy (TRFS) study of Eu(III) sorbed on γ-alumina at the metal ion concentration of 5.0 x 10 -5 M was carried out over pH 4 to 7. TRFS showed the presence of two surface species, with distinctly different fluorescence decay life times. The shorter lifetime value and its changing pattern with pH indicate the surface species corresponding to this component to be monodentate species > AlOAm 2+ and its hydrolyzed forms. The sorbed Eu 3+ species corresponding to the longer lifetime value has 2-3 water molecules in its first coordination sphere and is multidentate in its binding on alumina surface. Extended X-ray absorption fine structure (EXAFS) measurement of Eu:γ-Al 2 O 3 sorption systems at pH 6.18 and 7.15 corroborate the existence of two surface complexes. Further it suggests the edge sharing bidentate binding of Eu on AlO 6 octahedra as the co-ordination mode of the higher lifetime component. Surface Complexation Modeling (SCM) of Am(III)/Eu(III) sorption onto γ-alumina at pH ≤7 has been carried out using these two surface species. 2-pK surface complexation modeling coupled with constant capacitance model

L1 track trigger for the CMS HL-LHC upgrade using AM chips and FPGAs

Science.gov (United States)

Fedi, Giacomo

2017-08-01

The increase of luminosity at the HL-LHC will require the introduction of tracker information in CMS's Level-1 trigger system to maintain an acceptable trigger rate when selecting interesting events, despite the order of magnitude increase in minimum bias interactions. To meet the latency requirements, dedicated hardware has to be used. This paper presents the results of tests of a prototype system (pattern recognition ezzanine) as core of pattern recognition and track fitting for the CMS experiment, combining the power of both associative memory custom ASICs and modern Field Programmable Gate Array (FPGA) devices. The mezzanine uses the latest available associative memory devices (AM06) and the most modern Xilinx Ultrascale FPGAs. The results of the test for a complete tower comprising about 0.5 million patterns is presented, using as simulated input events traversing the upgraded CMS detector. The paper shows the performance of the pattern matching, track finding and track fitting, along with the latency and processing time needed. The pT resolution over pT of the muons measured using the reconstruction algorithm is at the order of 1% in the range 3-100 GeV/c.

L1 track trigger for the CMS HL-LHC upgrade using AM chips and FPGAs

Directory of Open Access Journals (Sweden)

Fedi Giacomo

2017-01-01

Full Text Available The increase of luminosity at the HL-LHC will require the introduction of tracker information in CMS’s Level-1 trigger system to maintain an acceptable trigger rate when selecting interesting events, despite the order of magnitude increase in minimum bias interactions. To meet the latency requirements, dedicated hardware has to be used. This paper presents the results of tests of a prototype system (pattern recognition ezzanine as core of pattern recognition and track fitting for the CMS experiment, combining the power of both associative memory custom ASICs and modern Field Programmable Gate Array (FPGA devices. The mezzanine uses the latest available associative memory devices (AM06 and the most modern Xilinx Ultrascale FPGAs. The results of the test for a complete tower comprising about 0.5 million patterns is presented, using as simulated input events traversing the upgraded CMS detector. The paper shows the performance of the pattern matching, track finding and track fitting, along with the latency and processing time needed. The pT resolution over pT of the muons measured using the reconstruction algorithm is at the order of 1% in the range 3-100 GeV/c.

Autoradiographic study on the distribution of 241Am in the shell of the freshwater zebra mussel Dreissena polymorpha

International Nuclear Information System (INIS)

Zuykov, M.; Pelletier, E.; Rouleau, C.; Popov, L.; Fowler, S.W.; Orlova, M.

2009-01-01

Autoradiography was used to identify α-track distributions in a series of shell sections from live mussels Dreissena polymorpha Pallas and dissected shells of dead mussels obtained from laboratory experiments using relatively high concentrations of 241 Am in the exposure media, a required condition for successful use of this autoradiographic technique. A comparable distribution of α-tracks was recorded on autoradiographs from both live and dead shells suggesting that metabolism does not lead to any sizable changes in the process of 241 Am adsorption (present in the extrapallial fluid) onto the inner surface of shell. Autoradiographs showed a preferential accumulation of 241 Am in the organic periostracum, whereas the outer and inner shell layers were characterized by a relatively low α-tracks density. No α-tracks were observed in the central part of the shell in any of the samples. These observations will be useful for the development of a general model to explain bioaccumulation and biosorption processes of radionuclides into mollusk shells. (author)

A comparative study of the carcinogenetic effects of 241Am, 239Pu and 237Np

International Nuclear Information System (INIS)

Wang Yumin; Wei Zhikang; Chen Xueyi; Yao Yongheng; Liu Peibin; Xu Lin; Lun Mingyao

1984-01-01

In this experiment, 420 wistar rats were used to study the comparative carcinogenetic effects of 241 Am, 239 Pu and 237 Np. These nuclides were injected to animals intravenously, subcutaneously or directly into the lung (Stansen's lung puncture method) in doses of 1.0, 5.0 and 8.5 μCi/kg, respectively. As soluble nitrate, the nuclides were rapidly transfered from the site of injection into the bone and the liver. Osteosarcomas were found in some animals 8 months to one year after intoxication. Diagnosis of osteosarcoma is based on the histopatological examination and X-ray photography. In the Am-poisoned rats the incidence of osteosarcoma is about 31-74%, varied with different doses and different routes of intoxication; in Pu-poisoned rats, the incidence of osteosarcoma is about 55-66%. while in Np-poisoned rats, it is about 36-53%. Primary lung cancers were also found in those animals poisoned by means of Stansen's lung puncture method with the above three nuclides. The incidence of primary lung cancers is about 6% in Am-and Pu-poisoned rats and 13% in Np-poisoned rats. The incidence of metastasis of osteosarcoma in lung is about 25-65% for Am-poisoned rats, 45-55% for Pu-poisoned rats and 41-80% for Np-poisoned rats. The life-span of above poisoned rats was significantly shorter than that of the normal control animals. The chemical weight for 241 Am, 239 Pu and 237 Np in same unit of radioactivity (1.0 μCi) equals to 0.308 μg, 15.9 μg and 1418.7 μg, respectively. For this reason, we have to pay more attention to the chemical mass effect in carcinogenesis of the above three nuclides

Charting a Course through CORAL: Texas A&M University Libraries' Experience Implementing an Open-Source Electronic Resources Management System

Science.gov (United States)

Hartnett, Eric; Beh, Eugenia; Resnick, Taryn; Ugaz, Ana; Tabacaru, Simona

2013-01-01

In 2010, after two previous unsuccessful attempts at electronic resources management system (ERMS) implementation, Texas A&M University (TAMU) Libraries set out once again to find an ERMS that would fit its needs. After surveying the field, TAMU Libraries selected the University of Notre Dame Hesburgh Libraries-developed, open-source ERMS,…

Delirium Research: Where Am I?

Science.gov (United States)

... of this page please turn JavaScript on. Feature: Delirium Research Where Am I? Past Issues / Fall 2015 Table of Contents The overlooked danger of delirium in hospitals In his mid-80s, Jerry (not ...

Radiocarbon measurements of small gaseous samples at CologneAMS

Science.gov (United States)

Stolz, A.; Dewald, A.; Altenkirch, R.; Herb, S.; Heinze, S.; Schiffer, M.; Feuerstein, C.; Müller-Gatermann, C.; Wotte, A.; Rethemeyer, J.; Dunai, T.

2017-09-01

A second SO-110 B (Arnold et al., 2010) ion source was installed at the 6 MV CologneAMS for the measurement of gaseous samples. For the gas supply a dedicated device from Ionplus AG was connected to the ion source. Special effort was devoted to determine optimized operation parameters for the ion source, which give a high carbon current output and a high 14C- yield. The latter is essential in cases when only small samples are available. Additionally a modified immersion lens and modified target pieces were tested and the target position was optimized.

78 FR 69629 - Revitalization of the AM Radio Service

Science.gov (United States)

2013-11-20

... sizeable portions of their audiences in the evening hours, and still others can provide no protected..., can block AM signals, hindering AM reception in urban areas where such structures are prevalent. Third... license ``should ensure sufficient flexibility in siting facilities and reaching target audiences...

Studies on preparing and adsorption property of grafting terpolymer microbeads of PEI-GMA/AM/MBA for bilirubin.

Science.gov (United States)

Gao, Baojiao; Lei, Haibo; Jiang, Liding; Zhu, Yong

2007-06-15

Crosslinking copolymer microbeads with a diameter range of 100-150 microm were synthesized by suspension copolymerization of glycidyl methacrylate (GMA), acrylamide (AM) and N,N'-methylene bisacrylamide (MBA). Subsequently, polyethyleneimine (PEI) was grafted on the surfaces of the terpolymer microbeads GMA/AM/MBA via the ring-opening reaction of the epoxy groups, and the grafting microbeads PEI-GMA/AM/MBA were prepared. In this paper, the adsorption property of the grafting microbeads for bilirubin was mainly investigated, and the effects of various factors, such as pH value, ionic strength and grafting degree of PEI on the surface of grafting microbeads and the adsorption capacity of the grafting microbeads for bilirubin were examined. The batch adsorption experiment results show that by right of the action of grafted polyamine macromolecules PEI, the grafting microbeads PEI-GMA/AM/MBA have quite strong adsorption ability for bilirubin; the isotherm adsorption conforms to Freundlich equation. The pH value of the medium affects the adsorption capacity greatly, As in the nearly neutral solutions with pH 6, the grafting microbeads have the strongest adsorption ability for bilirubin, whereas in acidic and basic solutions their adsorption ability is weak. The ionic strength hardly affects the adsorption ability of the grafting microbeads. The grafting degree of PEI on the surfaces of the grafting microbeads also has a great effect on the adsorption capacity, and higher the grafting degree of PEI on the surface of the microbead PEI-GMA/AM/MBA, the stronger is the adsorption ability of the microbeads.

Electronic structure of Pu-Ce(-Ga) and Pu-Am(-Ga) alloys, stabilized in the {delta} phase; Structure electronique d'alliages Pu-Ce(-Ga) et Pu-Am(-Ga) stabilises en phase {delta}

Energy Technology Data Exchange (ETDEWEB)

Dormeval, M

2001-09-01

The behaviour of {delta}-plutonium, stable between 319 and 451 deg C, exhibits numerous singularities which are still a mystery for both physicists and metallurgists. This is due to its complex electronic structure, and in particular to the 5f electrons, which are at the edge between localization and delocalization. The stability domain of the {delta} phase can be extended down to room temperature by alloying with so called 'deltagen atoms' such as gallium (Ga), aluminum (A1), cerium (Ce) or americium (Am). The present work deals, one the one hand, with the influence of cerium and americium solutes regarding the localization of the 5f electrons of {delta}-plutonium, in binary Pu-Ce and Pu-Am alloys. On the other hand, the effect of two different deltagen solutes, simultaneously present, on the stability of the {delta} phase has been studied in ternary Pu-Am-Ga and Pu-Ce-Ga alloys. The electronic structure being strongly related to the crystalline organization, characterization methods such as X-Ray diffraction and EXAFS measurements were used together with electrical resistivity and magnetic susceptibility experiments. These showed that the roles of cerium and americium, supposed to be similar at the beginning of this investigation, are actually very different. Moreover, the additive effect of cerium and gallium, and, americium and gallium, has been demonstrated. Studying plutonium alloys, which are radioactive, also means following their evolution in time. The characteristics of the alloys have then been followed which allowed to detect, in Pu-Ce(-Ga) alloys, a destabilization of the {delta} phase and, to observe, in Pu-Am(-Ga) alloys, the influence of self-irradiation defects on the magnetic response. (author)

Influence of previous experience on resistance training on reliability of one-repetition maximum test.

Science.gov (United States)

Ritti-Dias, Raphael Mendes; Avelar, Ademar; Salvador, Emanuel Péricles; Cyrino, Edilson Serpeloni

2011-05-01

The 1-repetition maximum test (1RM) has been widely used to assess maximal strength. However, to improve accuracy in assessing maximal strength, several sessions of the 1RM test are recommended. The aim of this study was to analyze the influence of previous resistance training experience on the reliability of 1RM test. Thirty men were assigned to the following 2 groups according to their previous resistance training experience: no previous resistance training experience (NOEXP) and more than 24 months of resistance training experience (EXP). All subjects performed the 1RM tests in bench press and squat in 4 sessions on distinct days. There was a significant session × group effect in bench press (F = 3.09; p reliability of the 1RM test is influenced by the subject's previous experience in resistance training. Subjects without experience in resistance training require more practice and familiarization and show greater increases in maximal strength between sessions than subjects with previous experience in resistance training.

77 FR 67239 - National Organic Program; Periodic Residue Testing

Science.gov (United States)

2012-11-09

... genetically modified organisms (GMOs). AMS does not intend for the testing conducted under section 205.670 to..., but not limited to, pesticides, hormones, antibiotics, and GMOs. AMS notes that, under section 205.671...

Forgery at the Snite Museum of Art? Improving AMS Radiocarbon Dating at the University of Notre Dame

Science.gov (United States)

Troyer, Laura; Bagwell, Connor; Anderson, Tyler; Clark, Adam; Nelson, Austin; Skulski, Michael; Collon, Philippe

2017-09-01

The Snite Museum of Art recently obtained several donations of artifacts. Five of the pieces lack sufficient background information to prove authenticity and require further analysis to positively determine the artwork's age. One method to determine the artwork's age is radiocarbon dating via Accelerator Mass Spectrometry (AMS) performed at the University of Notre Dame's Nuclear Science Laboratory. Samples are prepared by combustion of a small amount of material and subsequent reduction to carbon into an iron powder matrix (graphitization). The graphitization procedure affects the maximum measurement rate, and a poor graphitization can be detrimental to the AMS measurement of the sample. Previous graphitization procedures resulted in a particle current too low or inconsistent to optimize AMS measurements. Thus, there was a desire to design and refine the graphitization system. The finalized process yielded physically darker samples and increased sample currents by two orders of magnitude. Additionally, the first testing of the samples was successful, yet analysis of the dates proved inconclusive. AMS measurements will be performed again to obtain better sampling statistics in the hopes of narrowing the reported date ranges. NSF and JINA-CEE.

Information on the Advanced Plant Experiment (APEX) Test Facility

International Nuclear Information System (INIS)

Smith, Curtis Lee

2015-01-01

The purpose of this report provides information related to the design of the Oregon State University Advanced Plant Experiment (APEX) test facility. Information provided in this report have been pulled from the following information sources: Reference 1: R. Nourgaliev and et.al, 'Summary Report on NGSAC (Next-Generation Safety Analysis Code) Development and Testing,' Idaho National Laboratory, 2011. Note that this is report has not been released as an external report. Reference 2: O. Stevens, Characterization of the Advanced Plant Experiment (APEX) Passive Residual Heat Removal System Heat Exchanger, Master Thesis, June 1996. Reference 3: J. Reyes, Jr., Q. Wu, and J. King, Jr., Scaling Assessment for the Design of the OSU APEX-1000 Test Facility, OSU-APEX-03001 (Rev. 0), May 2003. Reference 4: J. Reyes et al, Final Report of the NRC AP600 Research Conducted at Oregon State University, NUREG/CR-6641, July 1999. Reference 5: K. Welter et al, APEX-1000 Confirmatory Testing to Support AP1000 Design Certification (non-proprietary), NUREG-1826, August 2005.

On the application of design of experiments to accelerated life testing

International Nuclear Information System (INIS)

Hakim-Mashhadi, M.

1992-01-01

Today, there is an increasing demand for improved quality and reliability due to increasing system complexity and increasing demands from customer. Continuous improvement of quality is not only a means of competition but also a matter of staying in the market. Accelerated life testing and statistical design of experiments are two needed methods for improvement of quality. The combined use of them is very advantageous and increases the test efficiency. Accelerated life testing is a quick way to provide information on the life distribution of materials and products. By subjecting the test unit to conditions more severe than those at normal usage, the test time can be highly reduced. Estimates of life at normal stress levels are obtained by extrapolating the available information through a reasonable acceleration model. Accelerated life testing has mostly been used to measure reliability but it is high time to use it for improvement of quality. Design of experiments serves to find out the effect of design parameters and other interesting factors on performance measure and its variability. The obtained information is essential for a continuous improvement of quality. As an illustration, two sets of experiment are designed and performed at highly increased stress levels. The results are analysed and discussed and a time saving alternative is proposed. The combination of experimental design and accelerated life testing is discussed and illustrated. The combined use of these methods can be argued for in two different cases. One is for an exploratory improvement investigation and the other is for verification of reliability. In either case, the combined use is advantageous and improves the testing efficiency. Some general conclusions are drawn to be used for planning and performance of statistically designed accelerated life testing experiments. (70 refs.) (au)

TRIGA criticality experiment for testing burn-up calculations

International Nuclear Information System (INIS)

Persic, Andreja; Ravnik, Matjaz; Zagar, Tomaz

1999-01-01

A criticality experiment with partly burned TRIGA fuel is described. 20 wt % enriched standard TRIGA fuel elements initially containing 12 wt % U are used. Their average burn-up is 1.4 MWd. Fuel element burn-up is calculated in 2-D four group diffusion approximation using TRIGLAV code. The burn-up of several fuel elements is also measured by reactivity method. The excess reactivity of several critical and subcritical core configurations is measured. Two core configurations contain the same fuel elements in the same arrangement as were used in the fresh TRIGA fuel criticality experiment performed in 1991. The results of the experiment may be applied for testing the computer codes used for fuel burn-up calculations. (author)

Oxygen Chemical Diffusion Coefficients of (Pu,Am)O2 Fuels

International Nuclear Information System (INIS)

Watanabe, M.; Kato, M.; Matsumoto, T.

2015-01-01

Minor actinide (MA)-bearing MOX fuels have been developed as candidate fuels which are used in fast neutron spectrum cores such as sodium-cooled fast reactor (SFR) cores and experimental accelerator driven system (ADS) cores. Americium (Am) which is one of the MA elements significantly affects basic properties. It is known that Am content causes oxygen potential to increase and that influences irradiation behaviour such as fuel-cladding chemical interaction (FCCI) and chemical state of fission products. However, the effects of Am content on changes of basic properties are not clear. In this work, the oxygen chemical diffusion coefficients were calculated from measured data and the relationship between oxygen diffusion and oxygen potential of (Pu,Am)O 2-x was discussed. (authors)

RFQ Reaction Cells for AMS: Developments and Applications

Directory of Open Access Journals (Sweden)

Kieser William E.

2013-12-01

Full Text Available The use of anion-gas interactions in Radiofrequency Quadrupole (RFQ ion guide reaction cells has been shown to be very effective in the elimination of a number of atomic and molecular isobars which have caused difficulties for Accelerator Mass Spectrometry (AMS measurements [1,2]. This presentation begins with a review of the early work leading to the use of ion-gas reactions and continues with a discussion the recent measurements of the efficacy of this technique, some of which involve fluoride molecular anions. However, the transformation of the equipment used for these proof-of-principle measurements into a system suitable for routine analysis has required attention to aspects of the ion beam transport and gas handling subsystems. For example, the cross sections of the ion-gas reactions, involving both the analyte ion as well as the isobar, are critically dependent on the ion energy which has to be reduced from the ion source energy, usually between 20 and 80 keV, to energies typically in the range of several eV, a task complicated by the energy spread and divergence of beams from AMS sputter sources. With simulations using SIMION 8.1 [3] and tests of promising configurations in a laboratory system, principles for the design of the retarder optics have been developed. These are discussed, along with their planned implementation in a next generation analytical system.

Am/Cm target glass durability dependence on pH (U). Revision 1

International Nuclear Information System (INIS)

Daniel, W.E.; Best, D.R.

1996-03-01

At the Westinghouse Savannah River Company near Aiken, South Carolina, a process is being developed to safely vitrify all of the highly radioactive americium/curium (Am/Cm) material and a portion of the other fissile actinide materials stored on site. One goal of this campaign is to provide Oak Ridge National Laboratory with the excess Am/Cm so it can be recycled as opposed to simply disposing of it as waste. The vitrification will allow safe transportation of the Am/Cm to Oak Ridge as well as safe storage once it arrives. The Am/Cm Target glass being used in this project has been specifically designed to be extremely durable in aqueous environments while it can be selectively attacked by nitric acid to recover the valuable Am and Cm isotopes. Similar glass compositions could be used for storage and retrieval of other actinides on the WSRC site. Previous reports have presented the time, temperature, and compositional dependence of the Am/Cm glass durability. This paper will show results from a pH study on the Am/Cm Target glass durability. The data indicate that the Am/Cm Target Glass durability decreases as pH decreases from a neutral reading. These findings support the extraction of the valuable isotopes from the glass using nitric acid

Mass of decaying wino from AMS-02 2014

Energy Technology Data Exchange (ETDEWEB)

Ibe, Masahiro [Tokyo Univ. (Japan). Inst. for Cosmic Ray Research; Univ. Tokyo (Japan). Kavli Inst. for the Physics and Mathematics of the Universe; Matsumoto, Shigeki; Yanagida, Tsutomu T. [Univ. Tokyo (Japan). Kavli Inst. for the Physics and Mathematics of the Universe; Shirai, Satoshi [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2014-09-15

We revisit the decaying wino dark matter scenario in the light of the updated positron fraction, electron and positron fluxes in cosmic ray recently reported by the AMS-02 collaboration. We show the AMS-02 results favor the mass of the wino dark matter at around a few TeV, which is consistent with the prediction on the wino mass in the pure gravity mediation model.

Mass of decaying wino from AMS-02 2014

Energy Technology Data Exchange (ETDEWEB)

Ibe, Masahiro, E-mail: ibe@icrr.u-tokyo.ac.jp [Institute for Cosmic Ray Research (ICRR), Theory Group, University of Tokyo, Kashiwa, Chiba 277-8568 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, Kashiwa, Chiba 277-8568 (Japan); Matsumoto, Shigeki [Kavli Institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, Kashiwa, Chiba 277-8568 (Japan); Shirai, Satoshi [Deutsches Elektronen-Synchrotron (DESY), 22607 Hamburg (Germany); Yanagida, Tsutomu T. [Kavli Institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, Kashiwa, Chiba 277-8568 (Japan)

2015-02-04

We revisit the decaying wino dark matter scenario in the light of the updated positron fraction, electron and positron fluxes in cosmic ray recently reported by the AMS-02 collaboration. We show the AMS-02 results favor the mass of the wino dark matter at around a few TeV, which is consistent with the prediction on the wino mass in the pure gravity mediation model.

Mass of decaying wino from AMS-02 2014

International Nuclear Information System (INIS)

Ibe, Masahiro

2014-09-01

We revisit the decaying wino dark matter scenario in the light of the updated positron fraction, electron and positron fluxes in cosmic ray recently reported by the AMS-02 collaboration. We show the AMS-02 results favor the mass of the wino dark matter at around a few TeV, which is consistent with the prediction on the wino mass in the pure gravity mediation model.

Droit administratif international - amélioration des rapports ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le nouveau site Web facilitera l'enregistrement des événements démographiques afin d'améliorer l'accès aux services pour tous. Le nouveau site Web et la nouvelle bibliothèque de ressources aideront à améliorer les systèmes d'information et d'enregistrement des faits d'état civil dans les pays en développement.

Microstructure and elemental distribution of americium containing MOX fuel under the short term irradiation tests

International Nuclear Information System (INIS)

Tanaka, Kosuke; Hirosawa, Takashi; Obayashi, Hiroshi; Koyama, Shin Ichi; Yoshimochi, Hiroshi; Tanaka, Kenya

2008-01-01

In order to investigate the effect of americium addition to MOX fuels on the irradiation behavior, the 'Am-1' program is being conducted in JAEA. The Am-1 program consists of two short term irradiation tests of 10-minute and 24 hour irradiations and a steady-state irradiation test. The short-term irradiation tests were successfully completed and the post irradiation examinations (PIEs) are in progress. The PIEs for Am-containing MOX fuels focused on the microstructural evolution and redistribution behavior of Am at the initial stage of irradiation and the results to date are reported

A comparative study of three cytotoxicity test methods for nanomaterials using sodium lauryl sulfate.

Science.gov (United States)

Kwon, Jae-Sung; Kim, Kwang-Mahn; Kim, Kyoung-Nam

2014-10-01

The biocompatibility evaluation of nanomaterials is essential for their medical diagnostic and therapeutic usage, where a cytotoxicity test is the simplest form of biocompatibility evaluation. Three methods have been commonly used in previous studies for the cytotoxicity testing of nanomaterials: trypan blue exclusion, colorimetric assay using water soluble tetrazolium (WST), and imaging under a microscope following calcein AM/ethidium homodimer-1 staining. However, there has yet to be a study to compare each method. Therefore, in this study three methods were compared using the standard reference material of sodium lauryl sulfate (SLS). Each method of the cytotoxicity test was carried out using mouse fibroblasts of L-929 exposed to different concentrations of SLS. Compared to the gold standard trypan blue exclusion test, both colorimetric assay using water soluble tetrazolium (WST) and imaging under microscope with calcein AM/ethidium homodimer-1 staining showed results that were not statistically different. Also, each method exhibited various advantages and disadvantages, which included the need of equipment, time taken for the experiment, and provision of additional information such as cell morphology. Therefore, this study concludes that all three methods of cytotoxicity testing may be valid, though careful consideration will be needed when selecting tests with regard to time, finances, and the amount of information required by the researcher(s).

The Formation Mechanism and Corrosion Resistance of a Composite Phosphate Conversion Film on AM60 Alloy

Science.gov (United States)

Lan, Xiangna; Wang, Chao; Zhang, Qinyong

2018-01-01

Magnesium alloy AM60 has high duc and toughness, which is expected to increase in demand for automotive applications. However, it is too active, and coatings have been extensively studied to prevent corrosion. In this work, a Ba-containing composite phosphate film has been prepared on the surface of AM60. The composition and formation mechanism of the film have been investigated using a scanning electronic microscope equipped with energy dispersive X-ray spectroscopy, Fourier transform infrared, X-ray photoelectron spectroscopy, and X-ray diffractometry tests. The corrosion resistance of the film has been measured by electrochemical and immersion tests. The results show that the deposition film has fully covered the substrate but there are some micro-cracks. The structure of the film is complex, and consists of MgHPO4·3H2O, MnHPO4·2.25H2O, BaHPO4·3H2O, BaMg2(PO4)2, Mg3(PO4)2·22H2O, Ca3(PO4)2·xH2O, and some amorphous phases. The composite phosphate film has better anticorrosion performance than the AM60 and can protect the bare alloy from corrosion for more than 12 h in 0.6 M NaCl. PMID:29518038

3D printed drug delivery and testing systems - a passing fad or the future?

Science.gov (United States)

Lim, Seng Han; Kathuria, Himanshu; Tan, Justin Jia Yao; Kang, Lifeng

2018-05-18

The US Food and Drug Administration approval of the first 3D printed tablet in 2015 has ignited growing interest in 3D printing, or additive manufacturing (AM), for drug delivery and testing systems. Beyond just a novel method for rapid prototyping, AM provides key advantages over traditional manufacturing of drug delivery and testing systems. These includes the ability to fabricate complex geometries to achieve variable drug release kinetics; ease of personalising pharmacotherapy for patient and lowering the cost for fabricating personalised dosages. Furthermore, AM allows fabrication of complex and micron-sized tissue scaffolds and models for drug testing systems that closely resemble in vivo conditions. However, there are several limitations such as regulatory concerns that may impede the progression to market. Here, we provide an overview of the advantages of AM drug delivery and testing, as compared to traditional manufacturing techniques. Also, we discuss the key challenges and future directions for AM enabled pharmaceutical applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Alpha spectrum analysis of 241Am in the urine

International Nuclear Information System (INIS)

Qiu Yongmei; Yang Yong

2006-10-01