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Sample records for magnetica nuclear na

  1. Magnetic nanoparticles for cancer therapy; Nanoparticulas magneticas para o tratamento do cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bakuzis, Andris F. [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Instituto de Fisica

    2014-07-01

    terapeutico para esta inovadora tecnica nao invasiva e altamente localizada. Nesta palestra iremos discutir resultados da literatura e do nosso proprio grupo no tratamento de cancer usando a hipertermia magnetica. Diversos tipos de nanoparticulas magneticas sugeridas para esta aplicacao serao apresentados assim como a evolucao historica deste tratamento, que apesar de ter sido sugerido em meados da decada de 50, so mais recentemente foi aprovado na Europa para tratamento de seres humanos com tumores do cerebro. (author)

  2. Imagenoligía para el siglo XXI resonancia magnetica

    OpenAIRE

    Mejía González, Mauricio; Fundación Valle de Lili

    1998-01-01

    ¿Qué es la resonancia magnetica?/¿Cómo funciona la resonancia magnética?/¿Para que se utiliza la resonancia magnética?/¿En que casos no se debe hacer resonancia magnética?/¿Se puede hacer resonancia a niños o mujeres embarazadas?/¿Qué se siente durante el examen?/¿Se requiere de medio de contraste?/¿Qué preparación previa se debe tener?/¿Que ventajas tiene la resonancia sobre otros métodos para imágenes diagnósticas?

  3. Studies on magnetocaloric and magnetic coupling effects =

    Science.gov (United States)

    Amaral, Joao Cunha de Sequeira

    O presente trabalho apresenta novas metodologias desenvolvidas para a analise das propriedades magneticas e magnetocaloricas de materiais, sustentadas em consideracoes teoricas a partir de modelos, nomeadamente a teoria de transicoes de fase de Landau, o modelo de campo medio molecular e a teoria de fenomeno critico. Sao propostos novos metodos de escala, permitindo a interpretacao de dados de magnetizacao de materiais numa perspectiva de campo medio molecular ou teoria de fenomeno critico. E apresentado um metodo de estimar a magnetizacao espontanea de um material ferromagnetico a partir de relacoes entropia/magnetizacao estabelecidas pelo modelo de campo medio molecular. A termodinamica das transicoes de fase magneticas de primeira ordem e estudada usando a teoria de Landau e de campo medio molecular (modelo de Bean-Rodbell), avaliando os efeitos de fenomenos fora de equilibrio e de condicoes de mistura de fase em estimativas do efeito magnetocalorico a partir de medidas magneticas. Efeitos de desordem, interpretados como uma distribuicao na interaccao magnetica entre ioes, estabelecem os efeitos de distribuicoes quimicas/estruturais nas propriedades magneticas e magnetocaloricas de materiais com transicoes de fase de segunda e de primeira ordem. O uso das metodologias apresentadas na interpretacao das propriedades magneticas de variados materiais ferromagneticos permitiu obter: 1) uma analise quantitativa da variacao de spin por iao Gadolinio devido a transicao estrutural do composto Gd5Si2Ge2, 2) a descricao da configuracao de cluster magnetico de ioes Mn na fase ferromagnetica em manganites da familia La-Sr e La-Ca, 3) a determinacao dos expoentes criticos β e δ do Niquel por metodos de escala, 4) a descricao do efeito da pressao nas propriedades magneticas e magnetocaloricas do composto LaFe11.5Si1.5 atraves do modelo de Bean-Rodbell, 5) uma estimativa da desordem em manganites ferromagneticas com transicoes de segunda e primeira ordem, 6) uma descricao de

  4. Application of nuclear magnetic resonance in osteoporosis evaluation; Aplicacoes de ressonancia magnetica nuclear na avaliacao de osteoporose

    Energy Technology Data Exchange (ETDEWEB)

    Giannoni, Ricardo A., E-mail: giannoni@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Montrazi, Elton T.; Bonagamba, Tito J., E-mail: elton.montrazi@gmail.com, E-mail: tito@ifsc.usp.br [Universidade de Sao Paulo (IFSC/USP), Sao Carlos, SP (Brazil). Inst. de Fisica; Cesar, Reinaldo, E-mail: reinaldofisica@gmail.com [Universidade de Sao Paulo (EESC/USP), Sao Carlos, SP (Brazil). Escola de Engenharia

    2013-07-01

    In this work, initially ceramic samples of known porosity were used. These ceramic samples were saturated with water. The nuclear magnetic resonance signal due to relaxation processes that the hydrogen nucleus water contained in the pores of this ceramic material was measured. Then these samples were subjected to a process of drying and measures successively. As the water contained in pores greater evaporates the intensity of signal decreases and shows the sign because of the smaller pores. The analysis of this drying process gives a qualitative assessment of the pore size of the material. In a second step, bones of animals of unknown porosity underwent the same methodology for evaluating osteoporosis. Also a sample of human vertebra in a unique manner, with the same purpose was measured. Combined with other techniques is a quantitative evaluation of the possible porosity.

  5. Use of nuclear magnetic resonance in the characterization of modified clays; Uso da ressonancia magnetica nuclear na caracterizacao de argilas modificadas

    Energy Technology Data Exchange (ETDEWEB)

    Leite, Sidnei Q.M. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia; Menezes, Sonia M.C. de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas; Gil, Rosane A.S. San [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica

    1992-12-31

    This work uses NMR spectroscopy with rotation in the {sup 29} Si, {sup 27} Al and {sup 23} Na magic angles for characterization of clays with Si/Al ratio in the range 3.0 - 16,5, obtained by chemical treatment of commercial samples, under different conditions of leaching with mineral acid 5 refs., 2 figs., 2 tabs.

  6. Nuclear magnetic resonance spectroscopy in biomedicine. Course organized by the Istituto Superiore di Sanita`. Marciana Marina (Isola d`Elba), September 18-23, 1995; Spettroscopia di risonanza magnetica nucleare in biomedicina. Corso organizzato dall`Istituto Superiore di Sanita`. Marciana Marina (Isola d`Elba), 18-23 settembre 1995

    Energy Technology Data Exchange (ETDEWEB)

    Luciani, A M; Rosi, A [ed.; Istituto Superiore di Sanita` , Rome (Italy). Lab. di Fisica

    1997-12-01

    Nuclear magnetic resonance is a powerful technique that can be used in a wide range of applications, such as the structural characterization of high molecular weight molecules, conformational studies on enzymes in solution, enzyme-substrate or DNA-protein interactions, monitoring of cell metabolism in vivo, and for diagnostic purposes, employing spectroscopic and imaging techniques. This course was organized in order to introduce the participants to the fundamentals of NMR spectroscopy, and offer practical advice on performing NMR experiments on cell systems, cell and tissue extracts and animal models. The main implications regarding human experiments were also discussed. Finally the quantification of information and the interpretation of data were considered with regard to the main nuclei observed. [Italiano] La risonanza magnetica nucleare e` una delle tecniche spettroscopiche che meglio risponde all`ampio spettro di condizioni imposto dalla ricerca in biofisica e biomedicina. Il campo applicativo di questa tecnica copre un intervallo molto ampio che va dalla caratterizzazione di strutture di macromolecole con elevato peso moleculare, a studi di tipo conformazionale su enzimi in soluzione e sull`interazione enzima-substrato o DNA-proteine, fino al monitoraggio in vivo del metabolosmi cellulare e alla diagnostica medica con spettroscopia ed imaging. Il corso e` stato articolato in modo da presentare ai partecipanti nozioni di base della spettroscopia RMN, aspetti pratici della realizzazione di esperimenti di spettroscopia in sistemi cellulari, in estratti cellulari e tissutali e in animali da esperimento, nonche` le principali considerazioni relative agli esperimenti nell`uomo. Sono state affrontate tematiche relative alla quantificazione dell`informazione e all`interpretazione dei dati in relazione ai principali nuclei osservati.

  7. Magnetic losses and reactance change by the use of metallic conduit in electrical installations; Perdidas magneticas y cambio de reactancia por la tuberia metalica en instalaciones electricas

    Energy Technology Data Exchange (ETDEWEB)

    Campero Littlewood, Eduardo; Castaneda D, Miguel; Castulo A, Roberto; Bratu Serban, Neagu [Universidad Autonoma Metropolitana-Azcapotzalco, Mexico, D. F. (Mexico)

    1996-12-31

    In this paper are presented the results obtained in the measurement of magnetic losses in metallic conduits in electric installations. The losses for parasitic currents and by hysteresis were obtained in different conditions of magnetic density, caused by the net current resulting from the sum of all the currents of all the conductors that travel along the conduit. These currents are named differential currents, and the conditions in which they appear in the electric installations are described. The magnetic induction phenomenon that occurs in metallic conduit is briefly described and the basic concepts that describe it. A theoretical-experimental methodology is offered to quantify the energy losses by parasitic currents and by the metal magnetization in these metallic conduits. At the same time, the impact of these differential currents impact in the reactance of the electric installation is quantified. The obtained results for twelve conduits of different diameters and different wall thickness are shown. A comparison analysis is made with the reported results in a previous article, where the losses were estimated by means of the temperature rise measurement of the metallic wall. [Espanol] En este articulo se presentan los resultados obtenidos en la medicion de perdidas magneticas en tuberias conduit (metalicas) en instalaciones electricas. Las perdidas por corrientes parasitas y por histeresis se obtuvieron para diferentes condiciones de densidad magnetica, provocada por la corriente neta resultante de la suma de las corrientes de todos los conductores que viajan por la tuberia. A estas corrientes se les designa corrientes diferenciales y se describen las condiciones en las que estas aparecen en las instalaciones electricas. Se explica brevemente el fenomeno de induccion magnetica que se presenta en las tuberias metalicas y los conceptos basicos que la describen. Se plantea una metodologia teorico-experiemental para cuantificar las perdidas de energia, por

  8. Magnetic losses and reactance change by the use of metallic conduit in electrical installations; Perdidas magneticas y cambio de reactancia por la tuberia metalica en instalaciones electricas

    Energy Technology Data Exchange (ETDEWEB)

    Campero Littlewood, Eduardo; Castaneda D, Miguel; Castulo A, Roberto; Bratu Serban, Neagu [Universidad Autonoma Metropolitana-Azcapotzalco, Mexico, D. F. (Mexico)

    1997-12-31

    In this paper are presented the results obtained in the measurement of magnetic losses in metallic conduits in electric installations. The losses for parasitic currents and by hysteresis were obtained in different conditions of magnetic density, caused by the net current resulting from the sum of all the currents of all the conductors that travel along the conduit. These currents are named differential currents, and the conditions in which they appear in the electric installations are described. The magnetic induction phenomenon that occurs in metallic conduit is briefly described and the basic concepts that describe it. A theoretical-experimental methodology is offered to quantify the energy losses by parasitic currents and by the metal magnetization in these metallic conduits. At the same time, the impact of these differential currents impact in the reactance of the electric installation is quantified. The obtained results for twelve conduits of different diameters and different wall thickness are shown. A comparison analysis is made with the reported results in a previous article, where the losses were estimated by means of the temperature rise measurement of the metallic wall. [Espanol] En este articulo se presentan los resultados obtenidos en la medicion de perdidas magneticas en tuberias conduit (metalicas) en instalaciones electricas. Las perdidas por corrientes parasitas y por histeresis se obtuvieron para diferentes condiciones de densidad magnetica, provocada por la corriente neta resultante de la suma de las corrientes de todos los conductores que viajan por la tuberia. A estas corrientes se les designa corrientes diferenciales y se describen las condiciones en las que estas aparecen en las instalaciones electricas. Se explica brevemente el fenomeno de induccion magnetica que se presenta en las tuberias metalicas y los conceptos basicos que la describen. Se plantea una metodologia teorico-experiemental para cuantificar las perdidas de energia, por

  9. High-resolution magneto stratigraphic of the Eocene-Oligocene boundary in the Umbria-Marche sequence; Stratigrafia magnetica ad alta risoluzione del limite Eocene-Oligocene nella successione Umbro-Marchigiana

    Energy Technology Data Exchange (ETDEWEB)

    Lanci, L.; Lowrie, W.; Montanari, A.

    1998-12-31

    High-resolution magneto stratigraphy across the Eocene-Olicene boundary has been employed in a detailed investigation of the nature of low-amplitude, short-wavelength oceanic magnetic anomalies. [Italiano] La stratigrafia magnetica ad alta risoluzione del limite Eocene-Oligocene ed il magnetismo delle rocce sono stati studiati in dettaglio per verificare la presenza di eventuali inversioni di polarita` brevi (short chrons) e variazioni delle intensita` del campo geomagnetico che possano essere messe in relazione con le anomalie oceaniche a bassa ampiezza e corto periodo.

  10. Nuclear spin polarized alkali beams (Li and Na): Production and acceleration

    International Nuclear Information System (INIS)

    Jaensch, H.; Becker, K.; Blatt, K.; Leucker, H.; Fick, D.

    1987-01-01

    Recent improvements of the Heidelberg source for polarized heavy ions (PSI) are described. By means of optical pumping in combination with the existing multipole separation magnet the beam figure of merit (polarization 2 x intensity) was doubled. 7 Li and 23 Na atomic beams can now be produced in pure hyperfine magnetic substates. Fast switching of the polarization is achieved by an adiabatic medium field transition. The hyperfine magnetic substate population is determined by laser-induced fluorescence spectroscopy. In routine operation atomic beams with nuclear polarization p α ≥0.85 (α=z, zz) are obtained. The acceleration of polarized 23 Na - ions by a 12 MV tandem accelerator introduces a new problem: the energy at the terminal stripper foil is not sufficient to produce a usable yield of naked ions. For partially stripped ions hyperfine interaction of the remaining electrons with the nuclear spin reduces the nuclear polarization. Using in addition the Heidelberg postaccelerator 23 Na 9+ beams of energies between 49 and 184 MeV were obtained with an alignment on target of P zz ≅0.45. 7 Li beams have also been accelerated up to 45 MeV with an alignment of P zz =0.69. (orig.)

  11. The Na+ transport in gram-positive bacteria defect in the Mrp antiporter complex measured with 23Na nuclear magnetic resonance.

    Science.gov (United States)

    Górecki, Kamil; Hägerhäll, Cecilia; Drakenberg, Torbjörn

    2014-01-15

    (23)Na nuclear magnetic resonance (NMR) has previously been used to monitor Na(+) translocation across membranes in gram-negative bacteria and in various other organelles and liposomes using a membrane-impermeable shift reagent to resolve the signals resulting from internal and external Na(+). In this work, the (23)Na NMR method was adapted for measurements of internal Na(+) concentration in the gram-positive bacterium Bacillus subtilis, with the aim of assessing the Na(+) translocation activity of the Mrp (multiple resistance and pH) antiporter complex, a member of the cation proton antiporter-3 (CPA-3) family. The sodium-sensitive growth phenotype observed in a B. subtilis strain with the gene encoding MrpA deleted could indeed be correlated to the inability of this strain to maintain a lower internal Na(+) concentration than an external one. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. MRI and MRCP of chronic pancreatitis. 1: technique and methods; La valutazione delle pancreatiti croniche con Risonanza Magnetica e colangiopancreatografia con Risonanza Magnetica. Prima parte: aspetti tecnico-metodologici

    Energy Technology Data Exchange (ETDEWEB)

    Laghi, A.; Pavone, P.; Catalano, C.; Panebianco, V.; Luccichenti, G.; Fabiano, S.; Passariello, R. [Rome Univ. La Sapienza, Rome (Italy). Ist. di Radiologia

    1999-10-01

    Until recently, MR examinations of the pancreas were limited by motion artifacts, vascular pulsatility and poor spatial resolution. Today, new techniques have been developed, which allow to overcome these problems and provide additional information such as selective images of biliary and pancreatic ducts and vascular structures. As a complement to baseline sequences, MR cholangiopancreatography images can be acquired, possibly integrated by functional examination after secretin administration. Finally, contrast-enhanced MR angiography opens new perspectives for vascular studies, particularly for the locoregional staging of pancreatic cancer. [Italian] Lo studio del pancreas con risonanza magnetica e' stato fino a pochi anni fa limitato dagli artefatti da movimento, da pulsatilita' vascolare e dalla ridotta risoluzione spaziale. Recentemente sono state sviluppate nuove tecniche che consentono da un lato di risolvere tali problemi e dall'altro di fornire informazioni aggiuntive, quali immagini selettive delle vie biliari e del dotto pancreatico e delle strutture vascolari. Come completamento all'esame di base si possono ottenere immagini di colangiopancreatografia con RM, eventualmente integrate da prove funzionali, rappresentate dall'iniezione di secretina. Infine, le nuove tecniche di angiografia con RM con mdc, nelle quali si effettua un'acquisizione durante la prima fase di passaggio arterioso o venoso dopo introduzione rapida del mdc a livello di una vena periferica, aprono nuove prospettive per lo studio vascolare, in particolare nella stadiazione loco-regionale dei processi neoplastici.

  13. Reuse of nuclear byproducts, NaF and HF in metal glass industries

    Energy Technology Data Exchange (ETDEWEB)

    Park, J.W.; Lee, H.W. [Korea Power Engineering Co., Inc., Kyunggi-do (Korea, Republic of); Yoo, S.H.; Moon, H.S.; Cho, N.C. [Korea Nuclear Fuel Co., Ltd., Daejon (Korea, Republic of)

    1997-02-01

    A study has been performed to evaluate the radiological safety and feasibility associated with reuse of NaF(Sodium Fluoride) and HF(Hydrofluoric Acid) which are generated as byproducts from the nuclear fuel fabrication process. The investigation of oversea`s experience reveals that the byproduct materials are most often used in the metal and glass industries. For the radiological safety evaluation, the uranium radioactivities in the byproduct materials were examined and shown to be less than radioactivities in natural materials. The radiation doses to plant personnel and the general public were assessed to be very small and could be ignored. The Korea nuclear regulatory body permits the reuse of NaF in the metal industry on the basis of associated radioactivity being {open_quote}below regulatory concern{close_quote}. HF is now under review for reuse acceptability in the steel and glass industries.

  14. Nuclear quadrupole interaction measurements of 19F* and 22Na* on Graphite

    International Nuclear Information System (INIS)

    Djoko-Surono, Th; Martin, Peter W

    1996-01-01

    Time differential perturbed angular distribution (TDPAD) technique has been used to investigate nuclear quadrupole interactions of 19 F * and 22 Na * in graphite. We concentrated the measurements on pseudo single crystal graphite called Highly Oriented Pyrolytic Graphite for it has an ordered structure in which the c-axes of the microcrystals aligned in a certain direction with the mosaic spread less than 1 o , while the a- and b-axes randomly oriented on a plane perpendicular to the c-axes. Interactions between quadrupole moment of 19 F * and 22 Na * with its surroundings electric field gradient were studied by detecting the γ-rays distribution, W(Θ,t). For 1 9F * we found one static interaction. The corresponding electric field gradient was V zz =3.24(19)x10 22 V/m 2 . In the case of 22 Na * we found no evidence of nuclear quadrupole interaction, however, we were able to conclude that |QV 22 | 19 bV/m 2 . Using theoretical calculation Q=0.06 barn, we find that |V zz | 20 V/m 2 . These results indicate that the value efg depend on two factors, the host crystal and the core electrons. The core electrons contribution to the total efg is considerably large

  15. Pelletizing of NaF granules as adsorbent for fluorides of nuclear fuel materials, (1)

    International Nuclear Information System (INIS)

    Kimura, Syojiro; Tsutsui, Tenson; Kanagawa, Akira.

    1976-01-01

    The pelletizing of NaF granules on laboratory scale used for recovery and purification of fluorides of nuclear fuel materials are investigated, particularity experimental studies on how to pelletize, fluidity of granules and flow rate of the granules in mortar of tablet machine are carried out. As result, added quantity of H 2 O as binder at granulation process of spherical NaF granule influence to yield of NaF granules. The proper quantity of H 2 O to NaF powder is about 18--19%. Friction coefficient of unfixed shape NaF granule is higher than that of spherical granule, in opposition, density of the former granule is lower. So fluidity of unfixed shape NaF granule is low, flow rate of the granules through feeder of tablet machine is slow, and arching on mortar of the tablet machine occurs. Then, some further operation for getting better fluidity needs for pelletizing of NaF granules using unfixed shape granule. The other hand, using spherical NaF granule, continuous pelletizing by commercial tablet machine can be carried out. (auth.)

  16. {sup 23}Na nuclear magnetic resonance study of the structure and dynamic of natrolite

    Energy Technology Data Exchange (ETDEWEB)

    Paczwa, Mateusz; Olszewski, Marcin; Sergeev, Nikolaj [Szczecin Univ. (Poland). Inst. of Physics; Sapiga, Aleksej A.; Sapiga, Aleksej V. [Taurida National V.I. Vernadsky Univ., Simferopol, Crimea (Ukraine)

    2015-07-01

    The temperature dependences of nuclear magnetic resonance (NMR) and magic angle spinning (MAS) NMR spectra of {sup 23}Na nuclei in natrolite (Na{sub 2}Al{sub 2}Si{sub 3}O{sub 10} . 2H{sub 2}O) have been studied. The temperature dependences of the spin-lattice relaxation times T{sub 1} in natrolite have also been studied. It has been shown that the spin-lattice relaxation of the {sup 23}Na is governed by the electric quadrupole interaction with the crystal electric field gradients modulated by translational motion of H{sub 2}O molecules in the natrolite pores. The dipolar interactions with paramagnetic impurities become significant as a relaxation mechanism of the {sup 23}Na nuclei only at low temperature (<270 K).

  17. Proceedings of the nuclear magnetic resonance user meeting. Anais do Encontro de Usuarios de Ressonancia Magnetica Nuclear

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    Studies on utilization of nuclear magnetic resonance, such as: chemical analysis in complexes and organic compounds; structures and magnetic properties of solids; construction of images and; spectrometer designs, are presented. (M.C.K.).

  18. Effect of Na{sub 2}O on aqueous dissolution of nuclear waste glasses

    Energy Technology Data Exchange (ETDEWEB)

    Farooqi, Rahmat Ullah, E-mail: rufarooqi@live.com [Division of Advanced Nuclear Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784 (Korea, Republic of); Hrma, Pavel [Division of Advanced Nuclear Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 790-784 (Korea, Republic of); Pacific Northwest National Laboratory, Richland, WA (United States)

    2017-04-15

    Sodium oxide is present in the majority of commercial and waste glasses as a viscosity-reducing component. In some nuclear waste glasses, its source is the waste itself. As such, it can limit the waste loading because of its deleterious effect on the resistance of the glass to attack by aqueous media. The maximum tolerable content of Na{sub 2}O in glass depends on the presence and concentration of components that interact with it. To assess the acceptability limits of Na{sub 2}O in the composition region of nuclear waste glasses, we formulated 11 baseline compositions by varying the content of oxides of Si, B, Al, Ca, Zr, and Li. In each of these compositions, we varied the Na{sub 2}O fraction from 8–16 mass% to 23–30 mass%. To each of 146 glasses thus formulated, we applied the seven-day Product Consistency Test (PCT) to determine normalized B and Na releases (r{sub i}, where i ≡ B or Na). Fitting approximation functions ln(r{sub i}/gm{sup −2}) = Σb{sub ij}g{sub j} to r{sub i} data (g{sub j} is the j-th component mass fraction and b{sub ij} the corresponding component coefficient), we showed that the r{sub B} (and, consequently, the initial glass alteration rate) was proportional to the glass component mass fractions in the order Al{sub 2}O{sub 3}Na{sub 2}O

  19. Pulse-shape discrimination between electron and nuclear recoils in a NaI(Tl) crystal

    International Nuclear Information System (INIS)

    Lee, H.S.; Adhikari, G.; Adhikari, P.; Choi, S.; Hahn, I.S.

    2015-01-01

    We report on the response of a high light-output NaI(Tl) crystal to nuclear recoils induced by neutrons from an Am-Be source and compare the results with the response to electron recoils produced by Compton-scattered 662 keV γ-rays from a 137 Cs source. The measured pulse-shape discrimination (PSD) power of the NaI(Tl) crystal is found to be significantly improved because of the high light output of the NaI(Tl) detector. We quantify the PSD power with a quality factor and estimate the sensitivity to the interaction rate for weakly interacting massive particles (WIMPs) with nucleons, and the result is compared with the annual modulation amplitude observed by the DAMA/LIBRA experiment. The sensitivity to spin-independent WIMP-nucleon interactions based on 100 kg⋅year of data from NaI detectors is estimated with simulated experiments, using the standard halo model.

  20. Pulse-shape discrimination between electron and nuclear recoils in a NaI(Tl) crystal

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H.S. [Department of Physics, Ewha Womans University,Seoul 120-750 (Korea, Republic of); Adhikari, G.; Adhikari, P. [Department of Physics, Sejong University,Seoul 143-747 (Korea, Republic of); Choi, S. [Department of Physics and Astronomy, Seoul National University,Seoul 151-747 (Korea, Republic of); Hahn, I.S. [Department of Science Education, Ewha Womans University,Seoul 120-750 (Korea, Republic of)

    2015-08-18

    We report on the response of a high light-output NaI(Tl) crystal to nuclear recoils induced by neutrons from an Am-Be source and compare the results with the response to electron recoils produced by Compton-scattered 662 keV γ-rays from a {sup 137}Cs source. The measured pulse-shape discrimination (PSD) power of the NaI(Tl) crystal is found to be significantly improved because of the high light output of the NaI(Tl) detector. We quantify the PSD power with a quality factor and estimate the sensitivity to the interaction rate for weakly interacting massive particles (WIMPs) with nucleons, and the result is compared with the annual modulation amplitude observed by the DAMA/LIBRA experiment. The sensitivity to spin-independent WIMP-nucleon interactions based on 100 kg⋅year of data from NaI detectors is estimated with simulated experiments, using the standard halo model.

  1. Crystalline phase of sodium germanate system determined by x-ray diffraction and 23Na magic angle spinning nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Hussin, R.; Holland, D.; Dupree, R.

    2000-01-01

    Crystalline products of sodium germanate glasses system with composition from 10 mol% to 50 mol% Na 2 O have been investigated using 23 Na magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy and x-ray diffraction (XRD). Fitting of the 23 Na NMR spectra of the crystalline phases concerning different crystallographically sodium atom in sodium germanate system are reasonably reproducible as observed by the spectra obtained. The line shape simulations of the 23 Na NMR spectra yielded NMR quadrupolar parameters such as nuclear quadrupole coupling constants (C Q ), asymmetry parameters (η), and isotropic chemical shifts (δ i ). 23 Na NMR isotropic chemical shift may also provide further information on the structural environment of the sodium atom. A simple correlation between structure and NMR parameters to be tested can be used to probe the structure of sodium germanate glasses. The experimental 23 Na chemical shifts correlate well with an empirical shift parameter based on the total oxygen-cation bond valence and Na-O distances of all oxygen atoms in the first coordination sphere of the sodium cation. In this study the different phases in the sodium germanate system were identified. These results show that 23 Na NMR can provide examples of the types of structural information for sodium germanate system. (Author)

  2. Centro de Energia Nuclear na Agricultura (CENA) - Sao Paulo, Brazil, - Annual report, 1978

    International Nuclear Information System (INIS)

    Anon.

    The activities carried out at 'Centro de Energia Nuclear na Agricultura (CENA) S.P., Brazil, in 1978 are related, such as : development of research on the use of radioisotopes in crop improvement and plant breeding, as well as in the improvement of animal production; works in collaboration with other entities; personnel formation and scientific exchange with other countries. (M.A.) [pt

  3. Nuclear magnetic resonance of D(-)-{alpha}-amino-benzyl penicillin; Ressonancia magnetica nuclear da D(-)-{alpha}-amino-benzil penicilina

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Monica R.M.P.; Gemal, Andre L.; San Gil, Rosane A.S. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica; Menezes, Sonia M.C. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    1995-12-31

    The development of new drugs from penicillins has induced the study of this substances by nuclear magnetic resonance. Several samples of D(-)-{alpha}-amino-benzyl penicillin were analysed using {sup 13} C NMR techniques in aqueous solution and solid state. Spectral data of this compounds were shown and the results were presented and analysed 7 figs., 4 tabs.

  4. Investigation on U - O - Na, Pu - O - Na and U,Pu - O - Na phase diagrams

    International Nuclear Information System (INIS)

    Pillon, S.

    1989-03-01

    The thermochemical interaction between the nuclear fuel (uranium and plutonium mixed oxides) and the sodium has been investigated and particularly the three phase diagrams: U - O - Na; Pu - O - Na; U,Pu - O - Na. High temperature neutron diffraction, microcalorimetry and powder X-ray diffraction were used for the characterization of the compounds synthetized. This study allowed to complete the knowledge about each of these diagrams and to measure some physical and thermal properties on the compounds. The limits on the modelization of the fuel-sodium interaction are discussed from the results of the UO 2 - Na reaction [fr

  5. Nuclear astrophysics with DRAGON at ISAC: the 21Na(p, γ)22Mg reaction

    International Nuclear Information System (INIS)

    D'Auria, J.M.

    2003-01-01

    The DRAGON facility at the new intense radioactive beams facility, ISAC, is now operational. It was built to perform studies of radiative alpha and proton capture reactions involving radioactive reactants, and of interest to nuclear astrophysics. The rate of the 21 Na(p, γ) 22 Mg reaction has been measured using inverse kinematics. Resonance strengths have been measured for states of importance for novae explosions. This report will summarize aspects of this study and its impact. (orig.)

  6. Study On Analytical Methods Of Tellurium Content In Natriiodide (Na131I) Radiopharmaceutical Solution Produced In The Dalat Nuclear Reactor

    International Nuclear Information System (INIS)

    Vo Thi Cam Hoa; Duong Van Dong; Nguyen Thi Thu; Chu Van Khoa

    2007-01-01

    This report describes the practical methods for analyzing of Tellurium content in Na 131 I solution produced at the Dalat Nuclear Research Institute. We studied analytical methods to control Tellurium content in final Na 131 I solution product used in medical purposes by three methods such as: spot test, gamma spectrometric and spectrophotometric methods. These investigation results are shown that the spot test method is suitable for controlling Tellurium trace in the final product. This spot test can be determinate Tellurium trace less than 10 ppm and are used to quality control of Na 131 I solution using in medical application. (author)

  7. Thermal expansion of the nuclear fuel-sodium reaction product Na{sub 3}(U{sub 0.84(2)},Na{sub 0.16(2)})O{sub 4} - Structural mechanism and comparison with related sodium-metal ternary oxides

    Energy Technology Data Exchange (ETDEWEB)

    Illy, Marie-Claire [Chimie ParisTech, PSL Research University, CNRS, Institut de Recherche de Chimie Paris (IRCP), F-75005 Paris (France); European Commission, Joint Research Centre, P.O. Box 2340, 76125 Karlsruhe (Germany); Smith, Anna L. [European Commission, Joint Research Centre, P.O. Box 2340, 76125 Karlsruhe (Germany); Delft University of Technology, Faculty of Applied Sciences, Department of Radiation Science & Technology, Nuclear Energy and Radiation Applications (NERA), Mekelweg 15, 2629 JB, Delft (Netherlands); Wallez, Gilles, E-mail: gilles.wallez@upmc.fr [Chimie ParisTech, PSL Research University, CNRS, Institut de Recherche de Chimie Paris (IRCP), F-75005 Paris (France); Sorbonne University, UPMC Université, Paris 06, 75005 Paris (France); Raison, Philippe E.; Caciuffo, Roberto; Konings, Rudy J.M. [European Commission, Joint Research Centre, P.O. Box 2340, 76125 Karlsruhe (Germany)

    2017-07-15

    Na{sub 3.16(2)}U{sup V,VI}{sub 0.84(2)}O{sub 4} is obtained from the reaction of sodium with uranium dioxide under oxygen potential conditions typical of a sodium-cooled fast nuclear reactor. In the event of a breach of the steel cladding, it would be the dominant reaction product forming at the rim of the mixed (U,Pu)O{sub 2} fuel pellets. High-temperature X-ray diffraction measurements show that a distortion of the uranium environment in Na{sub 3.16(2)}U{sup V,VI}{sub 0.84(2)}O{sub 4} results in a strongly anisotropic thermal expansion. A comparison with several related sodium metallates Na{sub n-2}M{sup n+}O{sub n-1} - including Na{sub 3}SbO{sub 4} and Na{sub 3}TaO{sub 4}, whose crystal structures are reported for the first time - has allowed us to assess the role played in the lattice expansion by the M{sup n+} cation radius and the Na/M ratio. On this basis, the thermomechanical behavior of the title compound is discussed, along with those of several related double oxides of sodium and actinide elements, surrogate elements, or fission products. - Highlights: •Thermal expansion and structural mechanism of Na{sub 3}(U{sub 0.84(2)},Na{sub 0.16(2)})O{sub 4}, main product of the reaction of sodium with nuclear fuel. •Thermomechanical behavior of sodium uranate suggests possible strains on the fuel cladding and risks of de-cohesion with the fuel pin. •Effect of homo- and aliovalent cation substitutions allows to predict the thermomechanical behavior of sodium metallates involving fission products or minor actinide elements. •Crystal structure of new compounds Na{sub 3}SbO{sub 4} and Na{sub 3}TaO{sub 4}.

  8. Diffusion and the dynamics of displacive phase transitions in cryolite (Na3AlF6) and chiolite (Na5Al3F14): Multi-nuclear NMR studies

    Science.gov (United States)

    Spearing, Dane R.; Stebbins, Jonathan F.; Farnan, Ian

    1994-10-01

    Cryolite is a mixed-cation perovskite (Na2(NaAl)F6) which undergoes a monoclinic to orthorhombic displacive phase transition at ˜550° C. Chiolite (Na5Al3F14) is associated with cryolite in natural deposits, and consists of sheets of corner sharing [AlF6] octahedra interlayered with edge-sharing [NaF6] octahedra. Multi-nuclear NMR line shape and relaxation time (T1) studies were performed on cryolite and chiolite in order to gain a better understanding of the atomic motions associated with the phase transition in cryolite, and Na diffusion in cryolite and chiolite. 27Al, 23Na, and 19F static NMR spectra and T1's in cryolite suggest that oscillatory motions of the [AlF6] octahedra among four micro-twin and anti-phase domains in α-cryolite begin at least 150° C below the transition temperature and persist above it. Variable temperature 23Na MAS NMR further indicates diffusional exchange at a rate of at least 13 kHz between the Na sites by the time the transition temperature is reached. 27Al and 23Na T1's show the same behavior with increasing temperature, indicating the same relaxation mechanisms are responsible for both. The first order nature of the cryolite transition is apparent as a jump in the 23Na and 27Al T1's. Above the transition temperature, the T1's decrease slightly indicating that the motions responsible for the drop in T1, are still present above the transition, further supporting the dynamic nature of the high temperature phase of cryolite. Chiolite 23Na static spectra decrease in linewidth with increasing temperature, indicating increased Na diffusion, which is interpreted as occurring within the [NaF6] sheets in the chiolite structure, but not between the two different Na sites. 27Al and 23Na T1's show similar behavior as in cryolite, but there is no discontinuity due to a phase transition. 19F T1's are constant from room temperature to 150° C indicating no oscillatory motion of the [AlF6] octahedra in chiolite.

  9. Proceedings of the 4. Meeting of the nuclear magnetic resonance users; Anais do 4. Encontro de usuarios de ressonancia magnetica nuclear

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    This book shows the papers presented in the 4. Meeting of Nuclear Magnetic Resonance Users which took place in Rio de Janeiro, Brazil, 1993. The main topics discussed were: solid state NMR; structural and conformational structure determination by NMR; perspectives for NMR in Brazil; recent achievements in NMR

  10. High resolution laser spectroscopy of the D lines of on-line produced 21Na, 22Na, 24Na, 25Na using a new high sensitivity method of detection of optical resonances

    International Nuclear Information System (INIS)

    Huber, G.; Thibault, G.; Klapisch, R.; Duong, H.T.; Vialle, J.L.; Pinard, I.; Juncar, P.; Jacquinot, P.

    1975-01-01

    A polyisotopic sodium beam of 21 - 25 Na, produced by spallation of Al, was illuminated by a tunable dye laser. The atomic beam, analyzed by a sixpole magnet is then ionized and detected after a mass spectrometer. The results are the isotope shifts, nuclear magnetic moment and quadrupole moment of 25 Na [fr

  11. Thermal expansion of the nuclear fuel-sodium reaction product Na3(U0.84(2),Na0.16(2))O4 - Structural mechanism and comparison with related sodium-metal ternary oxides

    Science.gov (United States)

    Illy, Marie-Claire; Smith, Anna L.; Wallez, Gilles; Raison, Philippe E.; Caciuffo, Roberto; Konings, Rudy J. M.

    2017-07-01

    Na3.16(2)UV,VI0.84(2)O4 is obtained from the reaction of sodium with uranium dioxide under oxygen potential conditions typical of a sodium-cooled fast nuclear reactor. In the event of a breach of the steel cladding, it would be the dominant reaction product forming at the rim of the mixed (U,Pu)O2 fuel pellets. High-temperature X-ray diffraction measurements show that a distortion of the uranium environment in Na3.16(2)UV,VI0.84(2)O4 results in a strongly anisotropic thermal expansion. A comparison with several related sodium metallates Nan-2Mn+On-1 - including Na3SbO4 and Na3TaO4, whose crystal structures are reported for the first time - has allowed us to assess the role played in the lattice expansion by the Mn+ cation radius and the Na/M ratio. On this basis, the thermomechanical behavior of the title compound is discussed, along with those of several related double oxides of sodium and actinide elements, surrogate elements, or fission products.

  12. Use of the image by nuclear magnetic resonance (nucleography) in obstetrical aspects. Part 1. Emprego da imagem por ressonancia magnetica nuclear (nucleografia) em obstetricia. Parte 1

    Energy Technology Data Exchange (ETDEWEB)

    Lacreta, O [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina

    1987-09-01

    Nuclear magnetic resonance (nucleography) is a new method to study human body. In this paper the physical principles on nuclear magnetic resonance and its applications to the pregnant women are presented. (author).

  13. High resolution spectroscopy in solids by nuclear magnetic resonance; Espectroscopia de alta resolucao em solidos por ressonancia magnetica nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Bonagamba, T J

    1991-07-01

    The nuclear magnetic resonance (NMR) techniques for High Resolution Spectroscopy in Solids are described. Also the construction project of a partially home made spectrometer and its applications in the characterization of solid samples are shown in detail. The high resolution spectrometer used is implemented with the double resonance multiple pulses sequences and magic angle spinning (MAS) and can be used with solid and liquid samples. The maximum spinning frequency for the MAS experiment is in excess of 5 Khz, the double resonance sequences can be performed with any type of nucleus, in the variable temperature operating range with nitrogen gas: -120{sup 0} C to +160{sup 0} C, and is fully controlled by a Macintosh IIci microcomputer. (author).

  14. Nuclear pore complex-mediated modulation of TCR signaling is required for naïve CD4+ T cell homeostasis.

    Science.gov (United States)

    Borlido, Joana; Sakuma, Stephen; Raices, Marcela; Carrette, Florent; Tinoco, Roberto; Bradley, Linda M; D'Angelo, Maximiliano A

    2018-05-07

    Nuclear pore complexes (NPCs) are channels connecting the nucleus with the cytoplasm. We report that loss of the tissue-specific NPC component Nup210 causes a severe deficit of naïve CD4 + T cells. Nup210-deficient CD4 + T lymphocytes develop normally but fail to survive in the periphery. The decreased survival results from both an impaired ability to transmit tonic T cell receptor (TCR) signals and increased levels of Fas, which sensitize Nup210 -/- naïve CD4 + T cells to Fas-mediated cell death. Mechanistically, Nup210 regulates these processes by modulating the expression of Cav2 (encoding Caveolin-2) and Jun at the nuclear periphery. Whereas the TCR-dependent and CD4 + T cell-specific upregulation of Cav2 is critical for proximal TCR signaling, cJun expression is required for STAT3-dependent repression of Fas. Our results uncover an unexpected role for Nup210 as a cell-intrinsic regulator of TCR signaling and T cell homeostasis and expose NPCs as key players in the adaptive immune system.

  15. The CERES / NA45 experiment

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    Ceres is one of the second generation heavy ion experiments at CERN's SPS. It is dedicated to the study of electron-positron pairs in relativistic nuclear collisions. NA45 is one of the seven experiments (NA44, NA45, NA49, NA50, NA52, WA97/NA57 and WA98) involved in CERN's Heavy Ion programme which provided evidence for the existence of a new state of matter, the quark-gluon plasma. In this state, quarks, instead of being bound up into more complex particles such as protons and neutrons, are liberated and roam freely. Theory predicts that this state must have existed at about 10 microseconds after the Big Bang, before the formation of matter as we know it today.

  16. Nuclear magnetic resonance of randomly diluted magnetic materials; Ressonancia nuclear magnetica em materiais magneticos diluidos aleatoriamente

    Energy Technology Data Exchange (ETDEWEB)

    Magon, C J

    1986-12-31

    The temperature dependence of the nuclear relaxation rates and line shapes of the F{sub O} resonance in the diluted antiferromagnet Fe{sub x} Zn{sub 1-x} F{sub 2} and Mn{sub x} Zn{sub 1-x} F{sub 2} are studied over a large temperature range T{sub N} < {approx} T {<=} 300 K. The high (room) temperature spin-lattice relaxation rates (1/T{sub 1}) of the F{sub O} nuclei, which are not transfer hyperfine coupled to the Fe (or Mn) spins, have been measured and calculated as a function of the concentration x. Good agreement with experiment is found for the theoretical results, which have been obtained in the range 0.1 {<=} x {<=} 0.8. The temperature dependence of 1/T{sub 1} for T{sub N}

  17. Characterization of sodium transport in Acholeplasma laidlawii B cells and in lipid vesicles containing purified A. laidlawii (Na+-Mg2+)-ATPase by using nuclear magnetic resonance spectroscopy and 22Na tracer techniques

    International Nuclear Information System (INIS)

    Mahajan, S.; Lewis, R.N.; George, R.; Sykes, B.D.; McElhaney, R.N.

    1988-01-01

    The active transport of sodium ions in live Acholeplasma laidlawii B cells and in lipid vesicles containing the (Na+-Mg2+)-ATPase from the plasma membrane of this microorganism was studied by 23Na nuclear magnetic resonance spectroscopic and 22 Na tracer techniques, respectively. In live A. laidlawii B cells, the transport of sodium was an active process in which metabolic energy was harnessed for the extrusion of sodium ions against a concentration gradient. The process was inhibited by low temperatures and by the formation of gel state lipid in the plasma membrane of this organism. In reconstituted proteoliposomes containing the purified (Na+-Mg2+)-ATPase, the hydrolysis of ATP was accompanied by the transport of sodium ions into the lipid vesicles, and the transport process was impaired by reagents known to inhibit ATPase activity. At the normal growth temperature (37 degrees C), this transport process required a maximum of 1 mol of ATP per mol of sodium ion transported. Together, these results provide direct experimental evidence that the (Na+-Mg2+)-ATPase of the Acholeplasma laidlawii B membrane is the cation pump which maintains the low levels of intracellular sodium characteristic of this microorganism

  18. Brain MRI lesions in neuromyelitis optica: clinical case; Lesiones cerebrales de resonancia magnetica en neuromielitis optica: caso clinico

    Energy Technology Data Exchange (ETDEWEB)

    Rosales Bravo, Luis Guillermo; Heyden Cordero, Marvin; Chinchilla Weinstok, Dennis; Mendelewicz Goldwaig, Isaias, E-mail: neurologia.cima@gmail.com [Caja Costarricense del Seguro Social, Hospital Mexico, Div. de Neurologia, San Jose (Costa Rica)

    2011-10-15

    Many cases of patients with neuromyelitis optica have submitted without demyelinating lesions in the cerebral white matter, it has documented that this entity can cause from the onset of illness or through its natural evolution. Diagnostic methods currently as Magnetic Resonance Imaging (MRI) and specific antibodies in plasma (such as antiaquaporin-4) have been diagnosed of neuromyelitis optica cases that were initially confused with multiple sclerosis. Disease in Costa Rica has been little prevalent and is not exactly known what the prevalence and incidence. The degree of disorder is illustrated through a case study, both in the cerebral white matter as spinal cord, in a patient with neuromyelitis optica during a follow-up period of 4 years. This is the first case that has been reported in the scientific literature of Costa Rica. (author) [Spanish] Muchos casos de pacientes con neuromielitis optica se han presentado sin lesiones desmielinizantes en la sustancia blanca cerebral, se ha documentado que esta entidad puede causarlas desde el inicio de la enfermedad o a traves de su evolucion natural. Los metodos de diagnostico en la actualidad como la Imagen por Resonancia Magnetica (IRM) y la determinacion de anticuerpos especificos en plasma (como la antiaquaporina-4) han logrado diagnosticar algunos casos de neuromielitis optica que inicialmente fueron confundidos con esclerosis multiple. La enfermedad en Costa Rica ha sido poco prevalente y no se ha conocido con exactitud cual es la prevalencia e incidencia. El grado de afeccion ha sido ilustrado a traves de un caso clinico, tanto en la sustancia blanca cerebral como espinal, en un paciente con neuromielitis optica durante un periodo de seguimiento de 4 anos. Este es el primer caso que ha sido reportado en la literatura cientifica de Costa Rica. (autor)

  19. Nuclear magnetic resonance in the evaluation of the disk luxation in the temporomandibular articulation conditioned for degenerative osseous changes; Resonancia magnetica nuclear en la valoracion de la luxacion discal en la articulacion temporomandibular condicionada por cambios degenerativos oseos

    Energy Technology Data Exchange (ETDEWEB)

    Marchegiani, Silvio; Guzman Urquhart, Romel; Marangoni, Alberto; Alvarez, Federico; Surur, Alberto [Sanatorio Allende, Cordoba (Argentina). Servicio de Diagnostico por Imagenes

    2006-07-01

    Purpose: The temporomandibular dysfunction is a common pathology. It appears with many symptoms as: joint pain, mechanic disturbance, and loss of mouth motion. The Magnetic Resonance Image is the chose method to study these alterations. The purposes of this paper are to demonstrate according to sex, the distribution of temporomandibular dysfunction and to determinant the relationships between the disc dislocation and the degenerative disease of the junction. Material and Method: 215 patients were evaluated between January 1999 and August 2004. An Elscint MRI 2 Tesla machine was used with Spin-echo (T1 and T2) Fat-sat sequences, in coronal, axial and sagittal planes. The follow alterations were evaluated: dislocation, degenerative disease of articular surface, osteochondritis, discal perforation, and retrodiscal lesions. Results: 175 of all showed pathologic alterations in IRM examination. The other 40 patients were excluded due to present a normal (MRI) study. The patients were 146 females and 29 men. The most common dislocation site was the anterior. Performance of the IRM was useful in all the cases to demonstrate degenerative changes in the temporomandibular joint (TMJ). And was a very precise relationship between the dislocation and degenerative disease of the joint. Conclusion: the female patient is the most frequently affected by temporomandibular joint pathology. The IRM is the selection method to study the TMJ. The degenerative changes are responsible for joint dislocation without reduction. (author) [Spanish] Proposito: Las disfunciones temporomandibulares son muy frecuentes. Los sintomas pueden ser: dolor a nivel de la articulacion, alteracion en la traslacion discocondilar (chasquido) y dificultad en la apertura bucal; dichos problemas conllevan a una consulta creciente de medicos clinicos como de odontologos. En la actualidad la Imagen por Resonancia Magnetica Nuclear (RM) es el estudio de eleccion. Los objetivos de este trabajo fueron demostrar la

  20. Nuclear spin phonon relaxation by Raman process in Na{sub 3}H(SO{sub 4}){sub 2} single crystals with the electric-quadrupole-type interaction using {sup 1}H and {sup 23}Na NMR

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Ae Ran [Department of Science Education, Jeonju University, Jeonju 560-759, Chonbuk (Korea, Republic of)], E-mail: aeranlim@hanmail.net; Shin, Chang Woo [Solid State Analysis Team, Korea Basic Science Institute, Daegu 702-701 (Korea, Republic of)

    2008-11-30

    Successive phase transitions in a Na{sub 3}H(SO{sub 4}){sub 2} single crystal were found at 296, 513, and 533 K. To investigate the mechanism of the phase transition at 296 K, the {sup 1}H and {sup 23}Na spin-lattice relaxation time and the spin-spin relaxation time of Na{sub 3}H(SO{sub 4}){sub 2} were measured near the phase transition temperature using a FT NMR spectrometer. The spin-lattice relaxation time, T{sub 1}, for {sup 1}H in Na{sub 3}H(SO{sub 4}){sub 2} crystals exhibits a minimum below T{sub C1} (=296 K) indicating the presence of distinct molecular motion governed by the Bloembergen-Purcell-Pound (BPP) theory. Although the results for the {sup 1}H and {sup 23}Na relaxation times provide no evidence of the phase transition at T{sub C1}, the separation of the {sup 23}Na resonance lines changes abruptly at T{sub C1}. The phase transition at 296 K produces a change in the separation of the Na resonance line that is associated with a change in the atomic positions in the vicinity of the Na ions. Also, the nuclear spin-lattice relaxation process in Na{sub 3}H(SO{sub 4}){sub 2} crystals with the electric-quadrupole-type interaction proceed via Raman process. These results are compared with those obtained for other M{sub 3}H(SO{sub 4}){sub 2} (M=K, Rb, and Cs) crystals, which have similar hydrogen-bonded structures.

  1. 22 Na positron source for annihilation positron spectroscopy

    International Nuclear Information System (INIS)

    Cimpeanu, Catalina; Craciun, L.; Dragulescu, E.; Dudu, D.; Racolta, P. M.; Voiculescu, Dana; Miron, N.

    2003-01-01

    To extend the nuclear physics applications and to perform the study of vacancy - type defects in metals, semiconductors, polymers etc., we decided to promote positron annihilation techniques. In order to achieve this goal we started a project of dedicated positron sources produced at the IFIN-HH U-120 Cyclotron. We have used the nuclear reaction: 24 Mg(d,α) 22 Na with deuterons of 13 MeV energy. The paper presents the main characteristics of this procedure, as follows: general conditions asked for 22 NaCl sources, reactive chamber and characteristics of Mg target, parameters for the irradiation, radiochemical procedures for separating Na from Mg after the irradiation and geometrical or mechanical requirements for dedicated NaCl source for positron annihilation spectrometry. In the e + lifetime measurements, the e + end - start signals may be obtained from prompt γ -quanta emitted from the NaCl source (1. 275 MeV photons). The 22 NaCl stock solution obtained by radiochemical separation will be kept in quartz sealed ampoules in dry places and will be dropped between the study materials before the use in positron spectrometry. (authors)

  2. 22 Na positron source for annihilation positron spectroscopy

    International Nuclear Information System (INIS)

    Cimpeanu, Catalina; Craciun, Liviu; Dragulescu, Emilian; Dudu, Dorin; Racolta, Petre Mihai; Voiculescu, Dana; Miron, N.

    2005-01-01

    To extend the nuclear physics applications and to perform the study of vacancy - type defects in metals, semiconductors, polymers, etc., we developed new positron annihilation techniques. In line with this goal we started a project for production of positron sources at the IFIN-HH U-120 Cyclotron. We made use of the nuclear reaction: 24 Mg(d,α) 22 Na with deuterons of 13 MeV energy. The paper present the main steps of this procedure which are: establishing the conditions required for 22 NaCl sources, for the parameters of reaction chamber and the characteristics of Mg target, parameters for the irradiation, radiochemical procedures for separation of Na from Mg after irradiation as well as the geometrical and mechanical requirements for the NaCl source. In the e + lifetime measurements the e + 'stop' signals are always provided by gamma - quanta generated by the e + e - annihilation and the 'start' signals are obtained from 'prompt' gamma - quanta emitted by the NaCl source (1.275 MeV photons). The 22 NaCl stock solution obtained by radiochemical separation will be kept in quartz sealed ampoules. (authors)

  3. 1H nuclear magnetic resonance studies of the conformation of an ATP analogue at the active site of Na,K-ATPase from kidney medulla

    International Nuclear Information System (INIS)

    Stewart, J.M.M.; Grisham, C.M.

    1988-01-01

    1 H nuclear magnetic relaxation measurements have been used to determine the three-dimensional conformation of an ATP analogue, Co(NH 3 ) 4 ATP, at the active site of sheep kidney Na,K-ATPase. Previous studies have shown that Co(NH 4 ) 4 ATP is a competitive inhibitor with respect to MnATP for the Na,K-ATPase and that Mn 2+ bound to a single, high-affinity site on the ATPase can be an effective paramagnetic probe for nuclear relaxation studies of the Na-K-ATPase. From the paramagnetic effect of Mn 2+ bound to the APTase on the longitudinal relaxation rates of the protons of Co(NH 3 ) 4 ATP at the substrate site (at 300 and 361 MHz), Mn-H distances to seven protons on the bound nucleotide were determined. Taken together with previous 31 P nuclear relaxation data, these measurements are consistent with a single nucleotide conformation at the active site. The nucleotide adopts a bent configuration, in which the triphosphate chain lies nearly parallel to the adenine moiety. The glycosidic torsion angle is 35 0 , and the conformation of the ribose ring is slightly N-type. The bound Mn 2+ lies above and in the plane of the adenine ring. The distances from Mn 2+ to N 6 and N 7 are too large for first coordination sphere complexes but are appropriate for second-sphere complexes involving, for example, intervening hydrogen-bonded water molecules. The NMR data also indicate that the structure of the bound ATP analogue is independent of the conformational state of the enzyme

  4. Scintillation efficiency measurement of Na recoils in NaI(Tl) below the DAMA/LIBRA energy threshold

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jingke; Shields, Emily; Calaprice, Frank; Westerdale, Shawn; Froborg, Francis; Suerfu, Burkhant; Alexander, Thomas; Aprahamian, Ani; Back, Henning O.; Casarella, Clark; Fang, Xiao; Gupta, Yogesh K.; Ianni, Aldo; Lamere, Edward; Lippincott, W. Hugh; Liu, Qian; Lyons, Stephanie; Siegl, Kevin; Smith, Mallory; Tan, Wanpeng; Kolk, Bryant Vande

    2015-07-01

    The dark matter interpretation of the DAMA modulation signal depends on the NaI(Tl) scintillation efficiency of nuclear recoils. Previous measurements for Na recoils have large discrepancies, especially in the DAMA/LIBRA modulation energy region. We report a quenching effect measurement of Na recoils in NaI(Tl) from 3 to 52 keVnr, covering the whole DAMA/LIBRA energy region for dark matter-Na scattering interpretations. By using a low-energy, pulsed neutron beam, a double time-of-flight technique, and pulse-shape discrimination methods, we obtained the most accurate measurement of this kind for NaI(Tl) to date. The results differ significantly from the DAMA reported values at low energies but fall between the other previous measurements. We present the implications of the new quenching results for the dark matter interpretation of the DAMA modulation signal.

  5. Seasonal variation in the environmental background level of cosmic ray produced 22Na

    International Nuclear Information System (INIS)

    Tokuyama, Hideki; Igarashi, Shuichi

    1998-01-01

    22 Na (half life 2.6 year) is produced by cosmic rays, nuclear test and reactor. 7 Be (half life 53.3 day) is produced in atmosphere by reaction. 7 Be/ 22 Na activity ratio is good factor to observe the mixing process between stratosphere and troposphere atmosphere. The seasonal variation of 7 Be and 22 Na deposition, the ratio and the background level of 22 Na deposition were observed in Fukui city and reported in this paper. Very large reasonable change of 22 Na deposition was observed, especially the largest peak in winter. Because the concentration of cosmic-ray-produced nuclear in precipitation and the amount of precipitation were large in winter. 22 Na produced by the previous nuclear test was attenuated. The present 22 Na is only produced by cosmic rays, indicating the background level. 22 Na deposition at Fukui was 0.42Bq m -2 y -1 , one ten-thousandth of 7 Be deposition. 7 Be/ 22 Na activity ratio was changed in season and the largest peak was shown in autumn. In this reason, atmosphere showed relatively short residence time in the lower part of stratosphere, Mixture and exchange of atmosphere between stratosphere and troposphere were the most active in autumn. (S.Y.)

  6. Characterisation of Ba(OH){sub 2}–Na{sub 2}SO{sub 4}–blast furnace slag cement-like composites for the immobilisation of sulfate bearing nuclear wastes

    Energy Technology Data Exchange (ETDEWEB)

    Mobasher, Neda; Bernal, Susan A.; Hussain, Oday H. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom); Apperley, David C. [Solid-State NMR Group, Department of Chemistry, Durham University, Durham DH1 3LE (United Kingdom); Kinoshita, Hajime [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom); Provis, John L., E-mail: j.provis@sheffield.ac.uk [Immobilisation Science Laboratory, Department of Materials Science and Engineering, The University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2014-12-15

    Soluble sulfate ions in nuclear waste can have detrimental effects on cementitious wasteforms and disposal facilities based on Portland cement. As an alternative, Ba(OH){sub 2}–Na{sub 2}SO{sub 4}–blast furnace slag composites are studied for immobilisation of sulfate-bearing nuclear wastes. Calcium aluminosilicate hydrate (C–A–S–H) with some barium substitution is the main binder phase, with barium also present in the low solubility salts BaSO{sub 4} and BaCO{sub 3}, along with Ba-substituted calcium sulfoaluminate hydrates, and a hydrotalcite-type layered double hydroxide. This reaction product assemblage indicates that Ba(OH){sub 2} and Na{sub 2}SO{sub 4} act as alkaline activators and control the reaction of the slag in addition to forming insoluble BaSO{sub 4}, and this restricts sulfate availability for further reaction as long as sufficient Ba(OH){sub 2} is added. An increased content of Ba(OH){sub 2} promotes a higher degree of reaction, and the formation of a highly cross-linked C–A–S–H gel. These Ba(OH){sub 2}–Na{sub 2}SO{sub 4}–blast furnace slag composite binders could be effective in the immobilisation of sulfate-bearing nuclear wastes.

  7. /sup 14/N nuclear quadrupole resonance in ferroelectric sodium nitrite NaNO/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S; Singh, K [Defence Science Lab., Delhi (India)

    1974-06-01

    Nuclear quadrupole resonance has been studied in ferroelectric sodium nitrite (NaNO/sub 2/) from 77 K to its phase transition point 437 K. The three rotational frequencies ..omega../sub c/ = 190 cm/sup -1/, ..omega../sub b/ = 120 cm/sup -1/ and ..omega../sub c/ = 227 cm/sup -1/ and their temperature variation when fitted in the Bayer-Kushida theory predict the temperature dependence of nqr frequencies reasonably well. A second order phase transition is found to occur at 180 K which is in confirmity with the one found earlier from thermal expansion and dielectric studies. The shift in resonance frequencies is seen to occur mainly by rotation around the 'c' axis and hence it is inferred that the mechanism of polarization reversal is intimately connected with orientational motion about 'c' axis. (auth)

  8. Professional Nuclear Materials Management; Gestion Industrielle des Matieres Nucleaires; Obrashchenie s yadernymi materialami na professional'nom urovne; Administracion Eficiente de Materiales Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Forcella, A. A.; O' Leary, W. J. [Allis-Chalmers Manufacturing Company, Bethesda, MD (United States)

    1966-02-15

    manipulacion y su transporte resulten economicos y sea facil sustituirlos. La programacion de las operaciones de fabricacion debera reducir al mfnimo las perdidas de ingresos debidas a un almacenamiento improductivo excesivamente largo de materiales de costo elevado. Para la etapa de su empleo en el reactor, sera necesario un programa adecuado de redistribucion de los elementos combustibles a fin de lograr el grado maximo de combustion del material fisionable. Ademas, habra que reducir en la medida de lo posible los paros improductivos del reactor debidos a la redistribucion del combustible, a las inspecciones, etc. Cuando el combustible haya llegado a un grado predeterminado de agotamiento, el administrador tendra que disponer la forma mas economica de regeneracion de los materiales fisionables y de recuperacion de los subproductos. La administracion de materiales nucleares es por consiguiente un factor esencial para la reduccion de los costos del ciclo del combustible y para lograr que el costo unitario de la energia producida resulte economicamente interesante. (author) [Russian] Daets ja opisanie ob{sup e}ma rabot na tipichnom jenergetichesko m reaktore v SShA. Poskol'ku jetot reaktor finansiruetsja chastnym kapitalom, odna iz osnovnyh objazannostej operatora sostoit v obespechenii sohrannosti kapitalovlozhenij i poluchenii opredelennoj pribyli. Vvidu bol'shoj sebestoimosti jadernyh materialov neobhodimo postojanno obespechivat' nadlezhashhuju bezopasnost' i uchet s cel'ju svedenija k minimumu poter', ne svjazannyh s obespe- cheniem bezopasnosti i ucheta jadernyh materialov. Neobhodimo vse tshhatel'no produmyvat' i planirovat' zaranee, chtoby izbegat' nenuzhnyh zatrat i rashodovanija kapitala ili snizhe- nija razmerov pribyli v rjade oblastej. Pojetomu administrator, vedajushhij jadernymi materialami, dolzhen zaranee uchityvat' vse nepredvidennye obstojatel'stva i osushhestvljat' postojannyj kontrol' nad otklonenijami ot standartov pri planirovanii vo vremja a

  9. Nuclear magnetic resonance in superionic conductors with fluorite-type structure; Ressonancia magnetica nuclear em condutores superionicos de estrutura fluorita

    Energy Technology Data Exchange (ETDEWEB)

    Souto, Sergio Paulo Amaral

    1991-12-31

    The {sup 19} F NMR relaxation times T{sub 1} and T{sub 2} were measured in ternary and nonstoichiometric compounds with the fluorite-type structure. We have studied the Na{sub 0-4} Y{sub 0-6} F{sub 2-2} crystal in the temperature range 600 K to 900 K, where the crystal has not the fluorite structure. The T{sub 1} values were measured in 2 Larmor frequencies: 20.42 MHz and 34.24 MHz. The results for T{sub 1} were seem to be qualitatively similar to those measured in the system with two inequivalent sublattices. The T{sub 2} measurements, in the Pb{sub O84} Bi{sub 0-16} F{sub 2-16} crystal, were made during temperature cycles in the range of 300 K to 830 K. The difference in activation energy between cooling and heating half cycles, found to be approximately 0.08 eV, appear to be associated with the change in the clusters structure and not to the energy of defect formation. Finally, similar T{sub 2} measurements during temperature cycling was made in K{sub 0-4} Bi{sub 0-6} F{sub 2-2} : 2% Pb F{sub 2} crystal, in the temperature range 300 K to 800 K, but in this case no difference in the cooling and heating results was observed. We also measured, in the same temperature range, the T{sub 1} relaxation time in 3 Larmor frequencies: 11.71 MHz, 20.42 MHz and 34.24 Mhz. This results appear to indicate the existence of two hopping mechanism. (author). 132 refs., 68 figs.

  10. 22 Na positron source for annihilation positron spectroscopy

    International Nuclear Information System (INIS)

    Cimpeanu, Catalina; Craciun, L.; Dragulescu, E.; Dudu, D.; Racolta, P.M.; Voiculescu, Dana; Miron, N.

    2002-01-01

    To extend the nuclear physics applications and to perform the study of vacancy - type defects in metals, semiconductors, polymers etc., we decided to promote positron annihilation techniques. In order to achieve this goal we started a project of dedicated positron sources produced at the IFIN-HH U-120 Cyclotron. We have used the nuclear reaction 24 Mg(d,α) 22 Na and deuterons of 13 MeV energy. The paper presents the main steps of this procedure like: general conditions required for 22 NaCl sources, reactive chamber and characteristics of Mg target, parameters for the irradiation, radiochemical procedures to separate Na from Mg after the irradiation and geometrical or mechanical requirements for dedicated NaCl source for positron annihilation spectrometry. In the e + lifetime measurements the e + 'death - stop' signals are always provided by γ - quanta generated by the e + e - annihilation and the 'birth - start' signals may be obtained from 'prompt' γ - quanta emitted from the NaCl source (the 1.275 MeV photons). The 22 NaCl stock solution obtained by radiochemical separation will be kept in the sealed quartz vials in dry places and will be dropped between the studied materials before use in positron spectrometry. (authors)

  11. Properties of self-assembled diluted magnetic semiconductor nanostructures =

    Science.gov (United States)

    Ankiewicz, Amelia Olga Goncalves

    Este trabalho centra-se na investigacao da possibilidade de se conseguir um semicondutor magnetico diluido (SMD) baseado em ZnO. Foi levado a cabo um estudo detalhado das propriedades magneticas e estruturais de estruturas de ZnO, nomeadamente nanofios (NFs), nanocristais (NCs) e filmes finos, dopadas com metais de transicao (MTs). Foram usadas varias tecnicas experimentais para caracterizar estas estruturas, designadamente difraccao de raios-X, microscopia electronica de varrimento, ressonancia magnetica, SQUID, e medidas de transporte. Foram incorporados substitucionalmente nos sitios do Zn ioes de Mn2+ e Co2+ em ambos os NFs e NCs de ZnO. Revelou-se para ambos os ioes dopantes, que a incorporacao e heterogenea, uma vez que parte do sinal de ressonancia paramagnetica electronica (RPE) vem de ioes de MTs em ambientes distorcidos ou enriquecidos com MTs. A partir das intensidades relativas dos espectros de RPE e de modificacoes da superficie, demonstra-se ainda que os NCs exibem uma estrutura core-shell. Os resultados, evidenciam que, com o aumento da concentracao de MTs, a dimensao dos NCs diminui e aumentam as distorcoes da rede. Finalmente, no caso dos NCs dopados com Mn, obteve-se o resultado singular de que a espessura da shell e da ordem de 0.3 nm e de que existe uma acumulacao de Mn na mesma. Com o objectivo de esclarecer o papel dos portadores de carga na medicao das interaccoes ferromagneticas, foram co-dopados filmes de ZnO com Mn e Al ou com Co e Al. Os filmes dopados com Mn, revelaram-se simplesmente paramagneticos, com os ioes de Mn substitucionais nos sitios do Zn. Por outro lado, os filmes dopados com Co exibem ferromagnetismo fraco nao intrinseco, provavelmente devido a decomposicao spinodal. Foram ainda efectuados estudos comparativos com filmes de ligas de Zn1-xFexO. Como era de esperar, detectaram-se segundas fases de espinela e de oxido de ferro nestas ligas; todas as amostras exibiam curvas de histerese a 300 K. Estes resultados suportam a

  12. NaK handling and removal

    International Nuclear Information System (INIS)

    Desreumaux, J.; Rodriguez, G.; Guigon, A.; Verdelli, J.; Thomine, G.

    1997-01-01

    Sodium-potassium alloy is used in specific application in French Fast Breeder Reactors as: cold traps, NaK bubbler for argon purification, valves and also in experimental irradiation devices. lt has been preferred to sodium because it is liquid from + 7 deg. C for the most common peritectic alloy. After its use, NaK is considered as a hazardous waste (nuclear or not) due to its high reactivity with air and water. The most important risk remains in handling NaK systems which have not been operated for some time. The NaK will be covered with a crust of the superoxide K02 which is a strong oxidising agent. Thermodynamically, K02 will react with most organic material or metallic dust or swarfs and can also react with additional NaK to give sufficient heat to boil part of the NaK, resulting in a sudden increase in pressure and small explosions. We describe the formation given to experimenters in our Sodium School and the CEA's experience in treating specific devices for transportation, decanting of tanks, tank opening and NaK removal. (author)

  13. The nuclear reaction model code MEDICUS

    International Nuclear Information System (INIS)

    Ibishia, A.I.

    2008-01-01

    The new computer code MEDICUS has been used to calculate cross sections of nuclear reactions. The code, implemented in MATLAB 6.5, Mathematica 5, and Fortran 95 programming languages, can be run in graphical and command line mode. Graphical User Interface (GUI) has been built that allows the user to perform calculations and to plot results just by mouse clicking. The MS Windows XP and Red Hat Linux platforms are supported. MEDICUS is a modern nuclear reaction code that can compute charged particle-, photon-, and neutron-induced reactions in the energy range from thresholds to about 200 MeV. The calculation of the cross sections of nuclear reactions are done in the framework of the Exact Many-Body Nuclear Cluster Model (EMBNCM), Direct Nuclear Reactions, Pre-equilibrium Reactions, Optical Model, DWBA, and Exciton Model with Cluster Emission. The code can be used also for the calculation of nuclear cluster structure of nuclei. We have calculated nuclear cluster models for some nuclei such as 177 Lu, 90 Y, and 27 Al. It has been found that nucleus 27 Al can be represented through the two different nuclear cluster models: 25 Mg + d and 24 Na + 3 He. Cross sections in function of energy for the reaction 27 Al( 3 He,x) 22 Na, established as a production method of 22 Na, are calculated by the code MEDICUS. Theoretical calculations of cross sections are in good agreement with experimental results. Reaction mechanisms are taken into account. (author)

  14. Dissolution of targets for the production of Mo-99: Part 1. Influence of NaOH concentration and the addition of NaNO3 and NaNO2 on the dissolution time

    International Nuclear Information System (INIS)

    Camilo, Ruth L.; Araujo, Izilda da C.; Mindrisz, Ana C.; Forbicini, Christina A.L.G. de O.

    2011-01-01

    Faced with global crisis in the production of radioisotope 99 Mo, which product of decay, 99 mTc, is the tracer element most often used in nuclear medicine and accounts for about 80% of all diagnostic procedures in vivo, since September 2008 Brazil is developing the project called Brazilian Multipurpose Reactor (RMB). Within the Brazilian Nuclear Program (PNB) the construction of the RMB, is seen as a long term solution to meet all domestic demand relative to the supply of radioisotopes and radiopharmaceuticals. In the process to be studied to obtain 99 Mo from irradiated UA1 x -A1 LEU targets employing alkaline dissolution, processing time should be minimized, considering the short half life of 99 Mo and 99 mTc, about 66 h and 6 h, respectively. That makes dissolution time a significant factor in the development of the process. This paper presents the results of alkaline dissolution of scraps of Al, used to simulate the dissolution process of UA1 x -A1 targets. Al corresponds to about 79% of the total weight of the UA1 x -A1 target. The effect of NaOH concentration on dissolution time for the interval of 1 to 3.5 mol.L-1 was studied, keeping the molar ratio in 1Al:2.16NaOH and the initial temperature of 88 degree C. The influence of reagent composition over dissolution time was studied using three different solutions: a) 3 mol.L -1 NaOH, b) 3 mol.L -1 NaOH/NaNO 3 and c) 3 mol.L -1 NaOH/NaNO 2 , keeping the same molar ratio and temperature. The results showed that the dissolution time decreases with increasing NaOH concentration and the addition of NaNO 3 or NaNO 2 in the NaOH solution reduces both dissolution time and volume of gases released. (author)

  15. /sup 1/H nuclear magnetic resonance studies of the conformation of an ATP analogue at the active site of Na,K-ATPase from kidney medulla

    Energy Technology Data Exchange (ETDEWEB)

    MacD. Stewart, J.M.; Grisham, C.M.

    1988-06-28

    /sup 1/H nuclear magnetic relaxation measurements have been used to determine the three-dimensional conformation of an ATP analogue, Co(NH/sub 3/)/sub 4/ATP, at the active site of sheep kidney Na,K-ATPase. Previous studies have shown that Co(NH/sub 4/)/sub 4/ATP is a competitive inhibitor with respect to MnATP for the Na,K-ATPase and that Mn/sup 2 +/ bound to a single, high-affinity site on the ATPase can be an effective paramagnetic probe for nuclear relaxation studies of the Na-K-ATPase. From the paramagnetic effect of Mn/sup 2 +/ bound to the APTase on the longitudinal relaxation rates of the protons of Co(NH/sub 3/)/sub 4/ATP at the substrate site (at 300 and 361 MHz), Mn-H distances to seven protons on the bound nucleotide were determined. Taken together with previous /sup 31/P nuclear relaxation data, these measurements are consistent with a single nucleotide conformation at the active site. The nucleotide adopts a bent configuration, in which the triphosphate chain lies nearly parallel to the adenine moiety. The glycosidic torsion angle is 35/sup 0/, and the conformation of the ribose ring is slightly N-type. The bound Mn/sup 2 +/ lies above and in the plane of the adenine ring. The distances from Mn/sup 2 +/ to N/sub 6/ and N/sub 7/ are too large for first coordination sphere complexes but are appropriate for second-sphere complexes involving, for example, intervening hydrogen-bonded water molecules. The NMR data also indicate that the structure of the bound ATP analogue is independent of the conformational state of the enzyme.

  16. Flow Components in a NaK Test Loop Designed to Simulate Conditions in a Nuclear Surface Power Reactor

    Science.gov (United States)

    Polzin, Kurt A.; Godfroy, Thomas J.

    2008-01-01

    A test loop using NaK as the working fluid is presently in use to study material compatibility effects on various components that comprise a possible nuclear reactor design for use on the lunar surface. A DC electromagnetic (EM) pump has been designed and implemented as a means of actively controlling the NaK flow rate through the system and an EM flow sensor is employed to monitor the developed flow rate. These components allow for the matching of the flow rate conditions in test loops with those that would be found in a full-scale surface-power reactor. The design and operating characteristics of the EM pump and flow sensor are presented. In the EM pump, current is applied to a set of electrodes to produce a Lorentz body force in the fluid. A measurement of the induced voltage (back-EMF) in the flow sensor provides the means of monitoring flow rate. Both components are compact, employing high magnetic field strength neodymium magnets thermally coupled to a water-cooled housing. A vacuum gap limits the heat transferred from the high temperature NaK tube to the magnets and a magnetically-permeable material completes the magnetic circuit. The pump is designed to produce a pressure rise of 5 psi, and the flow sensor's predicted output is roughly 20 mV at the loop's nominal flow rate of 0.5 GPM.

  17. Long-Range Effects of Na(+) Binding in Na,K-ATPase Reported by ATP.

    Science.gov (United States)

    Middleton, David A; Fedosova, Natalya U; Esmann, Mikael

    2015-12-01

    This paper addresses the question of long-range interactions between the intramembranous cation binding sites and the cytoplasmic nucleotide binding site of the ubiquitous ion-transporting Na,K-ATPase using (13)C cross-polarization magic-angle spinning (CP-MAS) solid-state nuclear magnetic resonance. High-affinity ATP binding is induced by the presence of Na(+) as well as of Na-like substances such as Tris(+), and these ions are equally efficient promoters of nucleotide binding. CP-MAS analysis of bound ATP with Na,K-ATPase purified from pig kidney membranes reveals subtle differences in the nucleotide interactions within the nucleotide site depending on whether Na(+) or Tris(+) is used to induce binding. Differences in chemical shifts for ATP atoms C1' and C5' observed in the presence of Na(+) or Tris(+) suggest alterations in the residues surrounding the bound nucleotide, hydrogen bonding, and/or conformation of the ribose ring. This is taken as evidence of a long-distance communication between the Na(+)-filled ion sites in the membrane interior and the nucleotide binding site in the cytoplasmic domain and reflects the first conformational change ultimately leading to phosphorylation of the enzyme. Stopped-flow fluorescence measurements with the nucleotide analogue eosin show that the dissociation rate constant for eosin is larger in Tris(+) than in Na(+), giving kinetic evidence of the difference in structural effects of Na(+) and Tris(+). According to the recent crystal structure of the E1·AlF4(-)·ADP·3Na(+) form, the coupling between the ion binding sites and the nucleotide side is mediated by, among others, the M5 helix.

  18. Evaluation of poly(vinylpyrrolidone) and collagen by Low Field Nuclear Magnetic Resonance Spectroscopy; Avaliacao da polivinilpirrolidona e do colageno por ressonancia magnetica nuclear de baixo campo

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Paula de M.; Tavares, Maria I.B. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Macromoleculas Professora Eloisa Mano]. E-mail: pmcosta@ima.ufrj.br

    2005-07-01

    Blends of natural and synthetic polymers represent a new class of materials with better mechanical properties and biocompatibility than those of the single components. Collagen and poly(vinylpyrrolidone) are well known for their important biological properties. The blending of collagen with poly(vinylpyrrolidone) makes it possible to obtain new materials in which strong interactions between the synthetic and biological components occur. Do to the excellent biocompatibility of these polymers, this blend has been much studied intending biomedical applications. And a one technique that can provide important information on molecular mobility, compatibility and even evaluate the interactions that can occur with these polymers is the Low Field Nuclear Magnetic Resonance Spectroscopy. Thus, the purpose of this work is to evaluate collagen and poly(vinylpyrrolidone) by Low Field Nuclear Magnetic Resonance Spectroscopy. From the values of relaxation times obtained, we can conclude that these materials have different interactions, and different mobility domains, confirming the heterogeneity and complexity of these materials. (author)

  19. Dissolution of targets for the production of Mo-99: Part 1. Influence of NaOH concentration and the addition of NaNO{sub 3} and NaNO{sub 2} on the dissolution time

    Energy Technology Data Exchange (ETDEWEB)

    Camilo, Ruth L.; Araujo, Izilda da C.; Mindrisz, Ana C.; Forbicini, Christina A.L.G. de O., E-mail: rcamilo@ipen.br, E-mail: icaraujo@ipen.br, E-mail: acmindri@ipen.br, E-mail: cforbici@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN/SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Faced with global crisis in the production of radioisotope {sup 99}Mo, which product of decay, {sup 99}mTc, is the tracer element most often used in nuclear medicine and accounts for about 80% of all diagnostic procedures in vivo, since September 2008 Brazil is developing the project called Brazilian Multipurpose Reactor (RMB). Within the Brazilian Nuclear Program (PNB) the construction of the RMB, is seen as a long term solution to meet all domestic demand relative to the supply of radioisotopes and radiopharmaceuticals. In the process to be studied to obtain {sup 99}Mo from irradiated UA1{sub x}-A1 LEU targets employing alkaline dissolution, processing time should be minimized, considering the short half life of {sup 99}Mo and {sup 99}mTc, about 66 h and 6 h, respectively. That makes dissolution time a significant factor in the development of the process. This paper presents the results of alkaline dissolution of scraps of Al, used to simulate the dissolution process of UA1{sub x}-A1 targets. Al corresponds to about 79% of the total weight of the UA1{sub x}-A1 target. The effect of NaOH concentration on dissolution time for the interval of 1 to 3.5 mol.L-1 was studied, keeping the molar ratio in 1Al:2.16NaOH and the initial temperature of 88 degree C. The influence of reagent composition over dissolution time was studied using three different solutions: a) 3 mol.L{sup -1} NaOH, b) 3 mol.L{sup -1} NaOH/NaNO{sub 3} and c) 3 mol.L{sup -1} NaOH/NaNO{sub 2}, keeping the same molar ratio and temperature. The results showed that the dissolution time decreases with increasing NaOH concentration and the addition of NaNO{sub 3} or NaNO{sub 2} in the NaOH solution reduces both dissolution time and volume of gases released. (author)

  20. Átomos na integração: a aproximação Brasil-Argentina no campo nuclear e a construção do Mercosul

    OpenAIRE

    Vargas, Everton Vieira

    1997-01-01

    Este trabalho tenciona ser uma reflexão sobre a importância da aproximação entre o Brasil e a Argentina no campo nuclear, na segunda metade da década de 80 e no início dos anos 90, como fundamento para a construção de um relacionamento novo que suplantou uma rivalidade histórica entre ambos. O processo de aproximação encetado com um propósito aparentemente econômico, tinha uma dimensão estratégica. As repercussões desse esforço iam além dos interesses bilaterais imediatos e se refletiram na b...

  1. Nuclear energy for use in Agriculture

    International Nuclear Information System (INIS)

    Cervellini, A.

    1981-01-01

    The utilization of nuclear energy to solve problems in agriculture, aiming to increase the food production, is presented. The projects that are being developed at CENA (Centro de Energia Nuclear na Agricultura) are showed. (E.G.) [pt

  2. Opaque Nuclear Strategy

    Science.gov (United States)

    2017-12-01

    Relationship, 0000271219, 1961. https://www.cia.gov/ library / readingroom/docs/DOC_0000271219.pdf. . Trends in South Africa’s Nuclear Security Policies ...official policy or position of the Department of Defense or the U.S. Government. IRB number ____N/A____. 12a. DISTRIBUTION / AVAILABILITY STATEMENT...how Israel and South Africa shaped those strategies. This research may contribute to better understanding possible policies of potential nuclear

  3. Mechanochemical transformations in Li(Na)AlH4-Li(Na)NH2 systems

    International Nuclear Information System (INIS)

    Dolotko, Oleksandr; Zhang Haiqiao; Ugurlu, Ozan; Wiench, Jerzy W.; Pruski, Marek; Scott Chumbley, L.; Pecharsky, Vitalij

    2007-01-01

    Mechanochemical transformations of tetrahydroaluminates and amides of lithium and sodium have been investigated using gas volumetric analysis, X-ray powder diffraction, solid-state nuclear magnetic resonance (NMR) and transmission electron microscopy. In a transformation of LiAlH 4 and LiNH 2 taken in an 1:1 molar ratio, the amount of released hydrogen (6.6 wt.% after 30 min ball milling) was higher than in any known one pot mechanochemical process involving a hydrogen-containing solid. A total of 4.3 wt.% of hydrogen is released by the NaAlH 4 -NaNH 2 system after 60 min ball milling; and 5.2 wt.% H 2 is released when LiAlH 4 and NaNH 2 or NaAlH 4 and LiNH 2 are ball milled for 90 min and 120 min, respectively. All transformations proceed at room temperature. The mechanism of the overall transformation MAlH 4 (s) + MNH 2 (s) → 2MH(s) + AlN(s) + 2H 2 (g) was identified based on detailed spectroscopic analysis of the intermediate (M 3 AlH 6 ) and final products of the ball milling process

  4. NMR studies of Na+-anion association effects in polymer electrolytes

    International Nuclear Information System (INIS)

    Greenbaum, S.G.; Pak, Y.S.; Wintergill, M.C.; Fontanella, J.J.

    1988-01-01

    23 Na nuclear magnetic resonance (NMR) measurements on poly (propylene oxide) (PPO) and siloxane based polymer electrolytes containing various sodium salts at a single nominal concentration are reported. In addition, differential scanning calorimetry (DSC) and electrical conductivity studies were carried out on the PPO materials. The NMR-determined mobile Na + concentrations and DSC results provide evidence for ionic aggregation effects which, for some samples, result in salt precipitation at elevated temperatures. 23 Na chemical shifts observed in solid state NMR due to mobile Na + -anion interactions influence ionic transport as well as the number of available carriers. (author). 19 refs.; 7 figs

  5. Sodium fast reactors energy conversion systems. Na-CO2 interaction. Comparison with Na-water interaction of conventional water Rankine cycle

    International Nuclear Information System (INIS)

    Latge, Christian; Simon, Nicole

    2006-01-01

    The Sodium Fast Reactor is a very promising candidate for the development of Fast Neutron Reactors. It is well known owing to its wide development since the 1950's, throughout all countries involved in the development of nuclear power plants. The development of Sodium-cooled fast neutron reactors is possible due to its very attractive sodium, nuclear, physical and even some of its chemical properties. Nevertheless, the operational feedback has shown that the concept has several drawbacks: difficulties for In-Service Inspection and Repair operations due to the sodium opacity and possible detrimental effects of its reactivity with air and water when the heat conversion is performed with a conventional Rankine cycle. Moreover, the various design projects have shown some difficulties in enhancing its competitiveness with regards to existing NPPs without any new innovative options, i.e. the possibility of suppressing the intermediate circuits and/or the development of an optimized energy conversion system. The Supercritical CO 2 Brayton Cycle option for the energy conversion has been widely suggested because of its high thermodynamic efficiency (over 40%), its potential compactness of the Balance Of Plant equipment due to the small-sized turbo machinery system, and for its applicability to both Direct or Indirect Cycle (Na, PbBi, He) assuming the hypothesis that the Supercritical CO 2 -Na interaction has less serious potential consequences than sodium-water consequences in the conventional Rankine cycle. Within the framework of the SMFR (Small Modular Fast Reactor) project, developed jointly by Argonne National Laboratory (ANL-USA), the 'Commissariat a l'Energie Atomique' (CEA) and Japan Atomic Energy Agency (JAEA, formerly Japan Nuclear Cycle development), this option has been selected and investigated. This paper deals with the study of the interaction between Na and CO 2 , based on a literature review: the result of this study will allow the definition of R and D

  6. Local anesthetics: interaction with human erythrocyte membranes as studied by {sup 1}H and {sup 31}P nuclear magnetic resonance; Anestesicos locais: interacao com membranas de eritrocitos de sangue humano, estudada por ressonancia magnetica nuclear de {sup 1}H e {sup 31}P

    Energy Technology Data Exchange (ETDEWEB)

    Fraceto, Leonardo Fernandes; Paula, Eneida de [Universidade Estadual de Campinas, SP (Brazil). Inst. de Biologia. Dept. de Bioquimica]. E-mail: depaula@unicamp.br

    2004-02-01

    The literature carries many theories about the mechanism of action of local anesthetics (LA). We can highlight those focusing the direct effect of LA on the sodium channel protein and the ones that consider the interaction of anesthetic molecules with the lipid membrane phase. The interaction between local anesthetics and human erythrocyte membranes has been studied by {sup 1}H and {sup 31}P nuclear magnetic resonance spectroscopy. It was found that lidocaine (LDC) and benzocaine (BZC) bind to the membranes, increase the mobility of the protons of the phospholipids acyl chains, and decrease the mobility and/or change the structure of the polar head groups. The results indicate that lidocaine molecules are inserted across the polar and liquid interface of the membrane, establishing both electrostatic (charged form) and hydrophobic (neutral form) interactions. Benzocaine locates itself a little deeper in the bilayer, between the interfacial glycerol region and the hydrophobic core. These changes in mobility or conformation of membrane lipids could affect the Na{sup +}-channel protein insertion in the bilayer, stabilizing it in the inactivated state, thus causing anesthesia. (author)

  7. Review on Material Synthesis and Characterization of Sodium (Na) Super-Ionic Conductor (NASICON)

    Science.gov (United States)

    Kimpa, M. I.; Mayzan, M. Z. H.; Yabagi, J. A.; Nmaya, M. M.; Isah, K. U.; Agam, M. A.

    2018-04-01

    Sodium (Na) Super Ionic Conductor (NASICON) has general formula Na1+ x Zr2P3- xSi x O12 (0 ≤x ≤ 3) derived from its parent compound, sodium zirconium phosphate NaZr2(PO4)3 (NZP) which belong to a rhombohedral crystal structure. This material consists of three-dimensional structure with interesting features such as low thermal expansion coefficient, thermal stability, gas sensor and nuclear waste immobilization that make it viable for industrial applications. Current study presents comprehensive studies on the synthesis and essential characteristics required to understand the theory behind the mechanism that justifies the study of NASICON structure and its application such as lithium ion rechargeable battery, gas sensor, and nuclear waste immobilization and so on.

  8. Quantitative analysis of water heavy by NMR spectroscopy; aplicacion de la resonancia magnetica nuclear al analisis cuantitativo de agua pesada

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Gil, V

    1975-07-01

    Nuclear Magnetic Resonance has been applied to a wide variety of quantitative problems. A typical example has been the determination of isotopic composition. In this paper two different analytical methods for the determination of water in deuterium oxide are described. The first one, employs acetonitril as an internal standard compound and in the second one calibration curve of signal integral curve versus amount of D{sub 2}O is constructed. Both methods give results comparable to those of mass spectrometry of IR spectroscopy. (Author) 5 refs.

  9. Aqueous partial molar heat capacities and volumes for NaReO4 and NaTcO4

    International Nuclear Information System (INIS)

    Lemire, R.J.; Saluja, P.P.S.; Campbell, A.B.

    1989-01-01

    As part of the Canadian Nuclear Fuel Waste Management Program, data are required to model the equilibrium thermodynamic behavior of key radionuclides at temperatures above 25 degree C. A flow microcalorimeter/densimeter system has been commissioned to measure heat capacities and densities of solutions containing radioactive species. Measurements for solutions of aqueous NaReO 4 (a common analogue for NaTcO 4 ) were made at seven temperatures (15 to 100 degree C) over the concentration range 0.05 to 0.2 mol·kg -1 . Subsequently, measurements were made for NaTcO 4 solutions under similar conditions. The heat capacity and density data are analyzed using Pitzer's ion-interaction model, and values of the NaReO 4 partial molar heat capacities are compared to literature values based on integral heats of solution. The agreement between the two sets of NaReO 4 data is good below 75 degree C, but only fair at the higher temperatures. Values of the partial molar volumes have also been derived. The uncertainties introduced by using thermodynamic data for ReO 4 - , in the absence of data for TcO 4 - , are discussed

  10. Thermochemical modeling of nuclear waste glass

    International Nuclear Information System (INIS)

    Spear, K.E.; Besmann, T.M.; Beahm, E.C.

    1998-06-01

    The development of assessed and consistent phase equilibria and thermodynamic data for major glass constituents used to incorporate high-level nuclear waste is discussed in this paper. The initial research has included the binary Na 2 O-SiO 2 , Na 2 O-Al 2 O 3 , and SiO 2 -Al 2 O 3 systems. The nuclear waste glass is assumed to be a supercooled liquid containing the constituents in the glass at temperatures of interest for nuclear waste storage. Thermodynamic data for the liquid solutions were derived from mathematical comparisons of phase diagram information and the thermodynamic data available for crystalline solid phases. An associate model is used to describe the liquid solution phases. Utilizing phase diagram information provides very stringent limits on the relative thermodynamic stabilities of all phases which exist in a given system

  11. Radiative heat transfer in the Na mist dispersion over the hot surface of liquid Na in the cooling system of nuclear reactor

    International Nuclear Information System (INIS)

    Kunitomo, T.; Shafey, H.M.

    1980-01-01

    The analysis has been carried out for the radiative heat transfer in the Na mist dispersion enclosed between the hot surface of liquid Na at temperature Tsub(n) and the cold surface of Na deposit at Tsub(c). The model selected for the present study represents the Na mist formed in a sodium cooled fast breeder reactor in which the condensed liquid particles are dispersed in the mixture of the Ar cover gas and the Na vapor. The analysis is based on replacing the inhomogeneous dispersing medium by three discrete homogeneous layers, and formulating the transfer equation for the monochromatic radiation in each layer according to the Chandrasekhar theory. The numerical calculations of the radiative qsub(r) and convective qsub(c) heat transfers have been performed for the wave length range lambda=1.6-30 μm and are compared. The qsub(r) has the same order of magnitude as the qsub(c) for all conditions of the mist dispersions. Both qsub(r) and qsub(c) increase by nearly equal rates with the increase of Tsub(H) and decrease by different rates with increasing Tsub(c). Variations of the particle diameter of the Na mist do not change substantially the qsub(r). Both qsub(r) and qsub(c) decrease slightly with the increase in the total thickness of the Na mist dispersion

  12. Pelletizing of NaF granules as adsorbent for fluorides of nuclear fuel materials, (2)

    International Nuclear Information System (INIS)

    Kimura, Syojiro; Tsutsui, Tenson; Kanagawa, Akira.

    1976-01-01

    Experimental studies on compressibility of NaF granules are investigated. Brittleness and porosity of a tableted pellet depend on compressive power applied to the granules. Relation of the compressive power and distortion of NaF granules agree with Kawakita's formula. About the brittleness of NaF pellet tableted with optional pressure, the follow experimental formula is formed between axial destructive power and compressive power. Dsub(p)=f.psup(n) Then, relation of the axial destructive power and porosity of NaF pellet is given from the above mentioned experimental formula and Kawakita's formula. At the lower value of the porosity than 0.4, the axial destructive power varies steeply as compared with variation of the porosity. At optional porosity, the brittleness of the tableted NaF pellet are lower than Harshow Chem. Co. NaF.HF pellet. So it requires some process raising the brittleness of the pellet after the compression. (auth.)

  13. Sepsis does not alter red blood cell glucose metabolism or Na+ concentration: A 2H-, 23Na-NMR study

    International Nuclear Information System (INIS)

    Hotchkiss, R.S.; Song, S.K.; Ling, C.S.; Ackerman, J.J.; Karl, I.E.

    1990-01-01

    The effects of sepsis on intracellular Na+ concentration ([Na+]i) and glucose metabolism were examined in rat red blood cells (RBCs) by using 23Na- and 2H-nuclear magnetic resonance (NMR) spectroscopy. Sepsis was induced in 15 halothane-anesthetized female Sprague-Dawley rats by using the cecal ligation and perforation technique; 14 control rats underwent cecal manipulation without ligation. The animals were fasted for 36 h, but allowed free access to water. At 36 h postsurgery, RBCs were examined by 23Na-NMR by using dysprosium tripolyphosphate as a chemical shift reagent. Human RBCs from 17 critically ill nonseptic patients and from 7 patients who were diagnosed as septic were also examined for [Na+]i. Five rat RBC specimens had [Na+]i determined by both 23Na-NMR and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). For glucose metabolism studies, RBCs from septic and control rats were suspended in modified Krebs-Henseleit buffer containing [6,6-2H2]glucose and examined by 2H-NMR. No significant differences in [Na+]i or glucose utilization were found in RBCs from control or septic rats. There were no differences in [Na+]i in the two groups of patients. The [Na+]i determined by NMR spectroscopy agreed closely with measurements using ICP-AES and establish that 100% of the [Na+]i of the RBC is visible by NMR. Glucose measurements determined by 2H-NMR correlated closely (correlation coefficient = 0.93) with enzymatic analysis. These studies showed no evidence that sepsis disturbed RBC membrane function or metabolism

  14. Nuclear physics with polarized heavy ions

    International Nuclear Information System (INIS)

    Fick, D.; Grawert, G.; Turkiewicz, I.M.

    1992-01-01

    Polarized heavy ion beams ( 6 Li, 7 Li, 23 Na) have been in use as tools for the investigation of nuclear scattering and nuclear reactions for almost two decades. This review attempts to survey the research activities in this field with reference to nuclear structure, nuclear dynamics and reaction mechanisms. Besides reviewing the results from full quantum mechanical coupled channels analyses of data, special attention is paid to handwaving arguments and semiclassical pictures as a complementary way of obtaining a better understanding of the relevant physics. (orig.)

  15. Problems and prospects of nuclear power industry

    International Nuclear Information System (INIS)

    Karelin, A.I.

    2001-01-01

    A consideration is given to problems associated with operating nuclear power plants in many countries and building new NPPs. A special attention is given to safety operation of nuclear plants, to reprocessing and transportation of spent nuclear fuel as well as to radioactive waste disposal. In connection with difficulties in solving the above-mentioned problems a proposition is made to resume work on designing NPPs with the use of nuclear liquid salt reactors based on molten fuel fluoride salts. Advantages and disadvantages of fuel compositions of LiF-BeF 2 -UF 4 -(ThF 4 ) are listed. It is recommended that fundamental studies be carried out into such compositions as KF + CsF; BaF 2 + KF + NaF; AlF 3 + Na 3 AlF 6 , eutectics on the basis of tin and zinc fluorides and their complex salts of M x Sn(Zn)F y . An international program is suggested to be developed to find some way out of crisis of nuclear power industry using research efforts in homogeneous liquid salt nuclear underground reactors with a U(233)-Th fuel cycle [ru

  16. Structural and Magnetic Studies on Iron Oxide Nanoparticles in Hybrid Matrices =

    Science.gov (United States)

    Silva, Nuno Joao de Oliveira

    Este trabalho aborda algumas propriedades magneticas e estruturais de nanoparticulas de oxidos e oxidos-hidroxidos de ferro crescidos em matrizes hibridas orgânicas-inorgânicas. As matrizes hibridas, denominadas di-ureasils e obtidas pelo processo sol-gel, sao compostas por uma rede siliciosa ligada covalentemente por pontes ureia a cadeias orgânicas de diferente peso molecular. A estrutura local dos di-ureasils nao dopados esta modelada como grupos de dominios siliciosos com dimensoes nanometricas, estruturalmente correlacionados no seio de uma matriz rica em polimero. Neste trabalho mostra-se que os di-ureasils permitem o crescimento controlado de oxidos e oxidos-hidroxidos de ferro, incluindo a magnetite, maguemite, oxihidroxinitrato de ferro e ferrihidrite. O crescimento das nanoparticulas de ferrihidrite da-se em condicoes acidas a superficie dos dominios siliciosos, junto aos grupos carbonilo, que funcionam como pontos de nucleacao. Desse modo da-se uma nucleacao heterogenea, onde o tamanho das nanoparticulas depende da concentracao de ferro (entre 1 e 6% em massa), sendo a concentracao de particulas constante. As propriedades magneticas das nanoparticulas de ferrihidrite revelam a existencia de interaccoes antiferromagneticas e de momentos descompensados. A contribuicao destas duas componentes nas curvas de magnetizacao em funcao do campo magnetico pode ser separada usando um metodo aqui proposto, o que permite um adequado estudo da evolucao do momento magnetico com a temperatura. O estudo das propriedades magneticas dinâmicas das particulas de ferrihidrite, atraves de susceptibilidade ac, medidas de relaxacao e medidas de efeito Mossbauer, permitiu estudar a evolucao das interaccoes dipolares em funcao da concentracao de ferro, bem como determinar a distribuicao de barreiras de energia de anisotropia no caso em que essas interaccoes sao desprezaveis. E apresentado um novo metodo para comparacao desta distribuicao com a distribuicao de tamanhos, que

  17. Spin-Transfer-Torque Nano-Oscillators: Fabrication, Characterization and Dynamics

    Science.gov (United States)

    Costa, Jose Diogo Teixeira Barbosa

    Este trabalho aborda algumas propriedades magneticas e estruturais de nanoparticulas de oxidos e oxidos-hidroxidos de ferro crescidos em matrizes hibridas orgânicas-inorgânicas. As matrizes hibridas, denominadas di-ureasils e obtidas pelo processo sol-gel, sao compostas por uma rede siliciosa ligada covalentemente por pontes ureia a cadeias orgânicas de diferente peso molecular. A estrutura local dos di-ureasils nao dopados esta modelada como grupos de dominios siliciosos com dimensoes nanometricas, estruturalmente correlacionados no seio de uma matriz rica em polimero. Neste trabalho mostra-se que os di-ureasils permitem o crescimento controlado de oxidos e oxidos-hidroxidos de ferro, incluindo a magnetite, maguemite, oxihidroxinitrato de ferro e ferrihidrite. O crescimento das nanoparticulas de ferrihidrite da-se em condicoes acidas a superficie dos dominios siliciosos, junto aos grupos carbonilo, que funcionam como pontos de nucleacao. Desse modo da-se uma nucleacao heterogenea, onde o tamanho das nanoparticulas depende da concentracao de ferro (entre 1 e 6% em massa), sendo a concentracao de particulas constante. As propriedades magneticas das nanoparticulas de ferrihidrite revelam a existencia de interaccoes antiferromagneticas e de momentos descompensados. A contribuicao destas duas componentes nas curvas de magnetizacao em funcao do campo magnetico pode ser separada usando um metodo aqui proposto, o que permite um adequado estudo da evolucao do momento magnetico com a temperatura. O estudo das propriedades magneticas dinâmicas das particulas de ferrihidrite, atraves de susceptibilidade ac, medidas de relaxacao e medidas de efeito Mossbauer, permitiu estudar a evolucao das interaccoes dipolares em funcao da concentracao de ferro, bem como determinar a distribuicao de barreiras de energia de anisotropia no caso em que essas interaccoes sao desprezaveis. E apresentado um novo metodo para comparacao desta distribuicao com a distribuicao de tamanhos, que

  18. QCD phase diagram under an external magnetic field

    Science.gov (United States)

    Ferreira, Marcio Rafael Baptista

    Neste trabalho e investigado o impacto de um campo magnetico externo na estrutura do diagrama de fases da Cromodinâmica Quântica (QCD). O estudo e realizado utilizando o modelo efetivo de Nambu-Jona-Lasinio para tres sabores acoplado ao loop de Polyakov (modelo de PNJL). A interacao de entanglement (modelo de EPNJL) na presenca de um campo magnetico e tambem estudada. Ambas as transicoes quiral e de desconfinamento na presenca de um campo magnetico externo podem ser analisadas usando os modelos de PNJL e EPNJL. Para o modelo de EPNJL e verificado que a coincidencia das temperaturas pseudocriticas de ambas as transicoes quiral e de deconfinamento dependem da parametrizacao da interacao de entanglement. E realizado um estudo sistematico do efeito de um campo magnetico externo nas transicoes quiral e de desconfinamento a potencial quimico barionico nulo, e.g., calculando a dependencia das temperaturas pesudocriticas com a intensidade do campo magnetico. O impacto de um campo magnetico externo no comportamento do quark estranho e analizado detalhadamente. E mostrado que a temperatura pseudocritica associada a transicao quiral do quark estranho e pouco sensivel a presenca de um campo magnetico externo. Alem disso, a sua grande massa corrente torna o quark estranho pouco sensivel ao termo de 't Hooft, contrariamente a forte influencia que tem nos quarks leves. Ambos os modelos de PNJL e EPNJL preveem o efeito de Catalise Magnetica a qualquer temperatura, mas nao reproduzem o efeito de Catalise Magnetica Inversa (CMI) em redor da temperatura pseudocritica de transicao, obtido em resultados recentes da LQCD. Mostramos que e possivel reproduzir a CMI se a intensidade da interacao entre quarks diminuir com o campo magnetico. Propomos dois mecanismos que reproduzem o efeito de CMI, que assumem o enfraquecimento da constante de acoplamento da interacao escalar com o aumento da intensidade do campo magnetico. O diagrama de fases e calculado para varios cenarios de isospin e

  19. Na,K-ATPase isozymes in colorectal cancer and liver metastases

    Directory of Open Access Journals (Sweden)

    Marc eBaker Bechmann

    2016-01-01

    Full Text Available The goal of this study was to define Na,K-ATPase α and β subunit isoform expression and isozyme composition in colorectal cancer cells and liver metastases. The α1, α3 and β1 isoforms were the most highly expressed in tumor cells and metastases; in the plasma membrane of non-neoplastic cells and mainly in a cytoplasmic location in tumor cells. α1β1 and α3β1 isozymes found in tumor and metastatic cells exhibit the highest and lowest Na+ affinity respectively and the highest K+ affinity. Mesenchymal cell isozymes possess an intermediate Na+ affinity and a low K+ affinity. In cancer, these ions are likely to favor optimal conditions for the function of nuclear enzymes involved in mitosis, especially a high intra-nuclear K+ concentration. A major and striking finding of this study was that in liver, metastasized CRC cells express the α3β1 isozyme. Thus, the α3β1 isozyme could potentially serve as a novel exploratory biomarker of CRC metastatic cells in liver.

  20. Portable in situ NaI(Tl) γ spectroscopy system

    International Nuclear Information System (INIS)

    Wang Bairong; Dong Binjiang; Zeng Liping; Shen Tingyun

    2000-01-01

    The author describes a portable in situ NaI(Tl) γ spectroscopy system, which consists of a NaI (Tl) scintillation detector, an integrative spectroscopy card, a notebook computer and spectroscopy software. The spectrometer addresses applications in environmental or nuclear accident in situ γ spectroscopy measurements, and gives valid quantitative results of radionuclide concentrations per unit volume (Bq/kg) or unit area (Bq/cm 2 ) in the soil and absorbed dose rate in air at 1 m above ground (Gy/h)

  1. Estimation of covariances of 16O, 23Na, Fe, 235U, 238U and 239Pu neutron nuclear data in JENDL-3.2

    International Nuclear Information System (INIS)

    Shibata, Keiichi; Nakajima, Yutaka; Kawano, Toshihiko; Oh, Soo-Youl; Matsunobu, Hiroyuki; Murata, Toru.

    1997-10-01

    Covariances of nuclear data have been estimated for 6 nuclides contained in JENDL-3.2. The nuclides considered are 16 O, 23 Na, Fe, 235 U, 238 U, and 239 Pu, which are regarded as important for the nuclear design study of fast reactors. The physical quantities for which covariances are deduced are cross sections, resolved and unresolved resonance parameters, and the first order Legendre-polynomial coefficient for the angular distribution of elastically scattered neutrons. As for 235 U, covariances were obtained also for the average number of neutrons emitted in fission. The covariances were estimated by using the same methodology that had been used in the JENDL-3.2 evaluation in order to keep a consistency between mean values and their covariances. The least-squares fitting code GMA was used in estimating covariances for reactions of which JENDL-3.2 cross sections had been evaluated by taking account of measurements. In nuclear model calculations, the covariances were calculated by the KALMAN system. The covariance data obtained were compiled in the ENDF-6 format, and will be put into the JENDL-3.2 Covariance File which is one of JENDL special purpose files. (author). 193 refs

  2. LS1 Report: NA62 readies for beam

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    On Wednesday, 10 September, the last NA62 straw tracker chamber was lowered into position in the experiment. This feat brings almost 8 years of CERN construction and design to a close, as the tracker has gone from the drawing board to construction and installation.   The final straw tracker module is lowered into position in NA62. The NA62 straw tracker is one of a kind. As the first of its scale to be placed directly into the vacuum tank of an experiment, it will allow NA62 physicists to measure the direction and momentum of charged particles with high precision. "From the first design to the final plug-in and testing, CERN teams have been 100% involved in developing this unique tracker," says Hans Danielsson, NA62 straw project leader. "We worked in close collaboration with the Joint Institute for Nuclear Research (JINR), Russia, who helped develop the straw tracker technology and will participate in the running of the detector now that construction and installa...

  3. Mechanochemical transformations in Li(Na)AlH{sub 4}-Li(Na)NH{sub 2} systems

    Energy Technology Data Exchange (ETDEWEB)

    Dolotko, Oleksandr [Ames Laboratory of the U.S. DOE, Iowa State University, Ames, IA 50011-3020 (United States); Zhang Haiqiao [Ames Laboratory of the U.S. DOE, Iowa State University, Ames, IA 50011-3020 (United States); Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011-2300 (United States); Ugurlu, Ozan [Ames Laboratory of the U.S. DOE, Iowa State University, Ames, IA 50011-3020 (United States); Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011-2300 (United States); Wiench, Jerzy W. [Ames Laboratory of the U.S. DOE, Iowa State University, Ames, IA 50011-3020 (United States); Pruski, Marek [Ames Laboratory of the U.S. DOE, Iowa State University, Ames, IA 50011-3020 (United States); Scott Chumbley, L. [Ames Laboratory of the U.S. DOE, Iowa State University, Ames, IA 50011-3020 (United States); Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011-2300 (United States); Pecharsky, Vitalij [Ames Laboratory of the U.S. DOE, Iowa State University, Ames, IA 50011-3020 (United States) and Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011-2300 (United States)]. E-mail: vitkp@ameslab.gov

    2007-05-15

    Mechanochemical transformations of tetrahydroaluminates and amides of lithium and sodium have been investigated using gas volumetric analysis, X-ray powder diffraction, solid-state nuclear magnetic resonance (NMR) and transmission electron microscopy. In a transformation of LiAlH{sub 4} and LiNH{sub 2} taken in an 1:1 molar ratio, the amount of released hydrogen (6.6 wt.% after 30 min ball milling) was higher than in any known one pot mechanochemical process involving a hydrogen-containing solid. A total of 4.3 wt.% of hydrogen is released by the NaAlH{sub 4}-NaNH{sub 2} system after 60 min ball milling; and 5.2 wt.% H{sub 2} is released when LiAlH{sub 4} and NaNH{sub 2} or NaAlH{sub 4} and LiNH{sub 2} are ball milled for 90 min and 120 min, respectively. All transformations proceed at room temperature. The mechanism of the overall transformation MAlH{sub 4}(s) + MNH{sub 2}(s) {sup {yields}} 2MH(s) + AlN(s) + 2H{sub 2}(g) was identified based on detailed spectroscopic analysis of the intermediate (M{sub 3}AlH{sub 6}) and final products of the ball milling process.

  4. CIRFT Data Update and Data Analyses for Spent Nuclear Fuel Vibration Reliability Study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    The objective of this research is to collect experimental data on spent nuclear fuel (SNF) from pressurized water reactors (PWRs), including the H. B. Robinson Nuclear Power Station (HBR), Catawba Nuclear Station, North Anna Nuclear Power Station (NA), and the Limerick Nuclear Power Station (LMK) boiling water reactor (BWR).

  5. Cross Section Measurements of the Reaction 23Na(p, γ)24Mg

    Science.gov (United States)

    Boeltzig, Axel; Deboer, Richard James; Macon, Kevin; Wiescher, Michael; Best, Andreas; Imbriani, Gianluca; Gyürky, György; Strieder, Frank

    2017-09-01

    The reaction 23Na(p, γ)24Mg can provide a link from the NeNa to the MgAl cycle in stellar burning and is therefore of interest in nuclear astrophysics. To determine the reaction rates at stellar temperatures, new cross section measurements at low proton energies have been performed recently, and further experiments are underway. The current cross section data implies that the reaction rate up to temperatures of 1 GK is determined by a few narrow resonances and direct capture. Complementary to these experimental efforts at low proton energies, cross section measurements at higher energies can help to constrain the direct capture and broad resonance contributions to the cross section and reduce the uncertainty of the extrapolation towards stellar energies. In this paper we report an experiment to measure the 23Na(p, γ)24Mg cross section with a solid target setup at the St. ANA 5U accelerator at the University of Notre Dame. The experiment and the current status of data analysis will be described. This work benefited from support by the National Science Foundation under Grant No. PHY-1430152 (JINA-CEE), the Nuclear Science Laboratory (NSL), the Istituto Nazionale di Fisica Nucleare (INFN), and the Gran Sasso Science Institute (GSSI).

  6. Stability of detecting system using NaI(Tl)

    International Nuclear Information System (INIS)

    Zhuo Yunshang; Lei Zhangyun; Zen Yu; Gong Hua

    1996-01-01

    A detecting system using NaI(Tl) is widely used in research and industry of nuclear science and other fields. For providing the high accuracy and working well under inclement environment, the stability of detecting system using NaI(Tl) is very important. The variation of environment temperature, the change of counting rate and long time continuous working of detector will cause un-negligible effect on the measurement. Three approaches were used. They are: 1) temperature control (It makes the effect of the variation of environment temperature on the measurement negligible.); 2) spectrum stabilizing (It adjust the peak position of the spectrum when the counting rate changes.); and 3) auto-checking and adjusting (It adjusts the drift of the NaI(Tl) detecting system when it works continuously)

  7. The J/$\\psi$ normal nuclear absorption

    CERN Document Server

    Alessandro, B; Arnaldi, R; Atayan, M; Beolè, S; Boldea, V; Bordalo, P; Borges, G; Castanier, C; Castor, J; Chaurand, B; Cheynis, B; Chiavassa, E; Cicalò, C; Comets, M P; Constantinescu, S; Cortese, P; De Falco, A; De Marco, N; Dellacasa, G; Devaux, A; Dita, S; Fargeix, J; Force, P; Gallio, M; Gerschel, C; Giubellino, P; Golubeva, M B; Grigorian, A A; Grigorian, S; Guber, F F; Guichard, A; kanyan, H; ldzik, M; Jouan, D; Karavicheva, T L; Kluberg, L; Kurepin, A B; Le Bornec, Y; Lourenço, C; Cormick, M M; Marzari-Chiesa, A; Masera, M; Masoni, A; Monteno, M; Musso, A; Petiau, P; Piccotti, A; Pizzi, J R; Prino, F; Puddu, G; Quintans, C; Ramello, L; Ramos, S; Riccati, L; Santos, H; Saturnini, P; Scomparin, E; Serci, S; Shahoyan, R; Sigaudo, M F; Sitta, M; Sonderegger, P; Tarrago, X; Topilskaya, N S; Usai, G L; Vercellin, E; Villatte, L; Willis, N; Wu T

    2005-01-01

    We present a new determination of the ratio of cross-sections (J/psi) /DY as expected for nucleus-nucleus reactions if J/psi would only be normally absorbed by nuclear matter. This anticipated behaviour is based on proton-nucleus data exclusively, and compared, as a function of centrality, with updated S-U results from experiment NA38 and with the most recent Pb-Pb results from experiment NA50.

  8. Nano-sized precipitated formations in irradiated NaCl

    NARCIS (Netherlands)

    Sugonyako, Anton V.

    2007-01-01

    The interest in the formation of radiation damage in alkali halides and in particular, in NaCl, is stimulated by the fact that rock-salt in stable geological formations is a prominent candidate medium for storage of high-level waste (HLW) of nuclear power plants. Since the 1950s, scientists and

  9. A portable in situ NaI(Tl) γ spectroscopy system

    International Nuclear Information System (INIS)

    Wang Bairong; Dong Binjiang; Zeng Liping

    1999-01-01

    The author describes a portable in situ NaI(Tl) γ spectroscopy system, which consists of a NaI(Tl) scintillation detector, an integrative spectroscopy card, a notebook computer and the spectroscopy software. The spectrometer addresses applications in environmental or nuclear accident in situ γ spectroscopy measurements, and gives valid quantitative results of radionuclide concentrations per unit volume (Bq/kg) or per unit area (Bq/cm 2 ) in the soil and absorbed dose rate in air 1 m above ground (Gy/h)

  10. Development of Na/sup 123/I pharmaceutical from antimony target

    Energy Technology Data Exchange (ETDEWEB)

    Yongjian, L.; Qixun, S.; Dequn, S. (Shanghai Inst. of Nuclear Research, Academia Sinica, Shanghai (China))

    A new method for the production of Na/sup 123/I is described. It is produced by the /sup 121/Sb(..cap alpha..,2n)/sup 123/I nuclear reaction and using a natural antimony target prepared by electroplating in a bath of antimony oxide and hydrofluoric acid. The target is irradiated with 32MeV ..cap alpha..-beams then transferred to a dry distillation apparatus and the iodide evolved and absorbed in NaOH. Quality control is by paper chromatography.

  11. Influence of communication on public opinion about nuclear energy; Influencia da comunicacao na aceitacao publica da energia nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Everton de Almeida [ELETROBRAS Termonuclear S.A., (ELETRONUCLEAR), Rio de Janeiro, RJ (Brazil)

    1997-12-31

    Public opinion on risks and benefits associated to nuclear energy is depending on psychological and social factors and mainly on the communication strategy used to transfer knowledge and facts about nuclear technology to the public. In this work, the individual and collective communication process and the influences on the public opinion on nuclear energy will be analyzed. (author) 3 refs., 1 fig.

  12. Nuclear and non-nuclear safety aspects in nuclear facilities dismantling. The example of a PWR pilot decommissioning project

    International Nuclear Information System (INIS)

    Massaut, V.; Deboodt, P.; Dadoumont, J.; Valenduc, P.; Denissen, L.

    2002-01-01

    The dismantling of nuclear facilities, and in particular of nuclear power plants, involves new challenges for the nuclear industry. Although the dismantling of various activated and contaminated components is nowadays considered as almost industrial practice, the safety aspects of decommissioning bring some specific features which are not always taken into account in the operation of the plants. Moreover, most of the plants and facilities currently decommissioned are rather old and were never foreseen to be decommissioned. The operations involved in dismantling and decontamination, often imply new or unforeseen situations. On the nuclear, or radiological side, the radioprotection optimisation of the operations involved often requires to model the environment and to analyse different scenarios to tackle the operation. Recent 3-D software (like the Visiplan software) allowing representation of the actual environment and the influence of the various sources present, is really needed to be able to minimise the radiological impact on the operators. The risk of contamination spread, by opening loops and components or by the dismantling process itself, is also an important aspect of the radiological protection study. Nevertheless, the radiological aspects of the safety approach are not the only ones to be dealt with when decommissioning nuclear facilities. Indeed, classical industrial safety aspects are also important: the dismantling can bring handling and transporting risk (heavy loads, difficult ways, uneasy access, etc.) but also the handling of toxic or hazardous materials. For instance, the removal of asbestos in contaminated areas can lead to additional hazard; the presence of alkali metals (like Na or NaK), of toxic metals (like e.g. Beryllium) or of corrosive fluids (acid,...) have to be tackled often in unstructured environment, and sometimes with limited knowledge of the actual situation. This leads to approach the operations following the ASARA principle (As

  13. Effect of TGFβ on Na+/K+ ATPase activity in megakaryocytes

    International Nuclear Information System (INIS)

    Hosseinzadeh, Zohreh; Schmid, Evi; Shumilina, Ekaterina; Laufer, Stefan; Borst, Oliver; Gawaz, Meinrad; Lang, Florian

    2014-01-01

    Highlights: • TGFß1 markedly up-regulates Na + /K + ATPase in megakaryocytes. • The effect is abrogated by p38-MAP kinase inhibitor skepinone. • The effect is abrogated by SGK inhibitor EMD638683. • The effect is abrogated by NF-κB inhibitor wogonin. - Abstract: The Na + /K + ATPase generates the Na + and K + concentration gradients across the plasma membrane and is thus essential for cellular electrolyte homeostasis, cell membrane potential and cell volume maintenance. A powerful regulator of Na + /K + ATPase is the serum- and glucocorticoid-inducible kinase 1 (SGK1). The most powerful known regulator of SGK1 expression is TGFß1, which is pivotal in the regulation of megakaryocyte maturation and platelet formation. Signaling involved in the upregulation of SGK1 by TGFß1 includes p38 mitogen activated protein (MAP) kinase. SGK1 in turn phosphorylates the IκB kinase (IKKα/β), which phosphorylates the inhibitor protein IκBα thus triggering nuclear translocation of nuclear factor kappa B (NF-κB). The present study explored whether TGFβ influences Na + /K + ATPase activity in megakaryocytes, and if so, whether the effect of TGß1 requires p38 MAP kinase, SGK1 and/or NF-κB. To this end, murine megakaryocytes were treated with TGFß1 and Na + /K + ATPase activity determined from K + induced current utilizing whole cell patch clamp. The pump current (I pump ) was determined in the absence and presence of Na + /K + ATPase inhibitor ouabain (100 μM). TGFß1 (60 ng/ml) was added in the absence or presence of p38 MAP kinase inhibitor skepinone-L (1 μM), SGK1 inhibitor EMD638683 (50 μM) or NF-κB inhibitor wogonin (50 nM). As a result, the I pump was significantly increased by pretreatment of the megakaryocytes with TGFß1, an effect reaching statistical significance within 16 and 24 h and virtually abrogated in the presence of skepinone-L, EMD638683 or wogonin. In conclusion, TGFß1 is a powerful regulator of megakaryocytic Na + /K + ATPase activity

  14. Thermodynamic description of Tc(iv) solubility and carbonate complexation in alkaline NaHCO3-Na2CO3-NaCl systems.

    Science.gov (United States)

    Baumann, A; Yalçıntaş, E; Gaona, X; Polly, R; Dardenne, K; Prüßmann, T; Rothe, J; Altmaier, M; Geckeis, H

    2018-03-28

    The solubility of 99 Tc(iv) was investigated in dilute to concentrated carbonate solutions (0.01 M ≤ C tot ≤ 1.0 M, with C tot = [HCO 3 - ] + [CO 3 2- ]) under systematic variation of ionic strength (I = 0.3-5.0 M NaHCO 3 -Na 2 CO 3 -NaCl-NaOH) and pH m (-log[H + ] = 8.5-14.5). Strongly reducing conditions (pe + pH m ≈ 2) were set with Sn(ii). Carbonate enhances the solubility of Tc(iv) in alkaline conditions by up to 3.5 log 10 -units compared to carbonate-free systems. Solvent extraction and XANES confirmed that Tc was kept as +IV during the timeframe of the experiments (≤ 650 days). Solid phase characterization performed by XAFS, XRD, SEM-EDS, chemical analysis and TG-DTA confirmed that TcO 2 ·0.6H 2 O(am) controls the solubility of Tc(iv) under the conditions investigated. Slope analysis of the solubility data in combination with solid/aqueous phase characterization and DFT calculations indicate the predominance of the species Tc(OH) 3 CO 3 - at pH m ≤ 11 and C tot ≥ 0.01 M, for which thermodynamic and activity models are derived. Solubility data obtained above pH m ≈ 11 indicates the formation of previously unreported Tc(iv)-carbonate species, possibly Tc(OH) 4 CO 3 2- , although the likely formation of additional complexes prevents deriving a thermodynamic model valid for this pH m -region. This work provides the most comprehensive thermodynamic dataset available for the system Tc 4+ -Na + -Cl - -OH - -HCO 3 - -CO 3 2- -H 2 O(l) valid under a range of conditions relevant for nuclear waste disposal.

  15. Comparison of Five Nuclear Isolation Buffers for Flow Cytometric ...

    African Journals Online (AJOL)

    Jocky

    2012-02-23

    Feb 23, 2012 ... species. A systematic comparison of nuclear lysis buffers has been ... All experiments were carried out with 3 replicates (n = 3) per treatment. ... Na2EDTA, 0.5 mM spermine.4HCl, 80 mM KCl, 20 mM NaCl, 0.1%. (v/v) Triton ...

  16. US and Russian academies forge ties for nuclear security

    International Nuclear Information System (INIS)

    Eldridge, Christopher A.

    2005-01-01

    In response to the growing threats of nuclear terrorism and proliferation, the US National Academies (NA) and the Russian Academy of Sciences (RAS) initiated a series of joint projects in early 2002 that bring their concerted expertise to bear on the challenges of cooperation between their two countries on nuclear non-proliferation. The IAEA has lent its talent and support to this inter-academy collaboration by hosting workshops that were jointly organized by the NA and RAS with financial support from the US-based Nuclear Threat Initiative. The two workshops, held at IAEA headquarters in September 2003, shed valuable light on both the obstacles and opportunities being faced. The first workshop explored ways of overcoming impediments to cooperation between the US and Russia on nuclear non-proliferation. Participants included current and former US and Russian government officials with responsibility for cooperative programs as well as experts from non-governmental organizations in the two countries. The second workshop convened a multinational group of experts on nuclear materials protection, control, and accounting (MPC and A) to discuss practices and procedures in light of the evolving threats of nuclear proliferation and terrorism

  17. How the Nuclear Applications Laboratories Help in Strengthening Emergency Response

    International Nuclear Information System (INIS)

    2014-01-01

    Safety is one of the most important considerations when engaging in highly advanced scientific and technological activities. In this respect, utilizing the potential of nuclear technology for peaceful purposes also involves risks, and nuclear techniques themselves can be useful in strengthening emergency response measures related to the use of nuclear technology. In the case of a nuclear incident, the rapid measurement and subsequent monitoring of radiation levels are top priorities as they help to determine the degree of risk faced by emergency responders and the general public. Instruments for the remote measurement of radioactivity are particularly important when there are potential health risks associated with entering areas with elevated radiation levels. The Nuclear Science and Instrumentation Laboratory (NSIL) — one of the eight laboratories of the Department of Nuclear Sciences and Applications (NA) in Seibersdorf, Austria — focuses on developing a variety of specialized analytical and diagnostic instruments and methods, and transferring knowledge to IAEA Member States. These include instruments capable of carrying out remote measurements. This emergency response work carried out by the NA laboratories supports health and safety in Member States and supports the IAEA’s mandate to promote the safe and peaceful use of nuclear energy

  18. Lanthanide oxide and phosphate nanoparticles for thermometry and bimodal imaging =

    Science.gov (United States)

    Debasu, Mengistie Leweyehu

    . Finalmente, estudam-se as propriedades de fotoluminescencia correspondentes as conversoes ascendente e descendente de energia em nanocristais de (Gd,Yb,Tb)PO4 sintetizados por via hidrotermica. A relaxividade (ressonancia magnetica) do 1H destes materiais sao investigadas, tendo em vista possiveis aplicacoes em imagem bimodal (luminescencia e ressonancia magnetica nuclear).

  19. Assessment of maximal erythrocyte Na+, K+-ATPase activity in patients with various arterial hypertensions by using 23Na NMR

    International Nuclear Information System (INIS)

    Revazov, A.V.; Knubovets, T.L.; Sibel'dina, L.A.; Sumarokov, A.V.; AN SSSR, Moscow

    1990-01-01

    The paper provides measurements of maximal erythrocyte Na + , K + -ATPase activity in 20 patients with hypertensive disease, 20 patients with secondary hypertension and 20 healthy donors. The investigation was made by high-resolution nuclear magnetic resonance using sodium nuclei. A significant decrease was found in Na + , K + -ATPase activity in the patients with hypertensive disease (9.0±0.3 mg-equiv. per liter cells an hour) as compared with those with secondary hypertension (10.3±0.3 mg-equiv. per liter cells an hour) and the controls (10.5±0.3 mg-equiv. per liter cells an hour), which supports the finding of impaired membrane morphology in hypertensive disease

  20. Environmental background level of cosmic ray produced 22Na

    International Nuclear Information System (INIS)

    Tokuyama, H.; Oonishi, M.; Matsuura, H.

    1993-01-01

    The annual deposition rate of cosmogenic 22 Na has been studied at Fukui City, Japan, to obtain the current background level. The deposition rate was found to range from 0.16 to 0.22 Bq m -2 y -1 with a mean value of 0.20 Bq m -2 y -1 for the years 1986-1990. The author's results agree fairly well with those observed for the years 1975-1977 in Tokyo. The 22 Na concentration in rain water was also estimated. The mean value for this period was found to be 0.09 mBq litre -1 , which is about one-third of that detected during the latter half of the 1950's. The high levels of environmental 22 Na in the 1950's are attributed to the many nuclear weapon tests conducted at that time. At present, however, the 22 Na from these weapons tests has practically decayed and the concentration in rain water has decreased to the natural background level. (Author)

  1. Informal Progress Report Contract Number: DE-FG03-02NA00074/A000

    International Nuclear Information System (INIS)

    Brune, Carl R.; Grimes, Steven M.

    2003-01-01

    OAK B127 We report on work performed under contract DE-FG03-03NA00074 since January 1,2003. The research is in the area of low energy nuclear reactions and nuclear structure. The progress on research on level densities and improvement to R-Matrix calculations are presented. The preparations to begin high resolution experiments on p-shell nuclei are reviewed

  2. Production of no carrier added residue free /sup 22/Na

    Energy Technology Data Exchange (ETDEWEB)

    Britto, J L.Q. de; Bastos, M A.V.; Silva, R.F. da; Silva, A.G. da

    1988-05-02

    A method for the production of no carrier added and residue free /sup 22/Na, was developed via the /sup 24/Mg(d,..cap alpha..)/sup 22/Na nuclear reaction applying 14 MeV deuterons and a high current MG-Cu target. The yield for the reaction was measured and the chemical separation was performed using a Dowex 50WX8 resin in H/sup +/ form. The overall yield was higher than 98%. Residue could not be detected. All experiments were carried out at IEN's CV-28 cyclotron. (author) 13 refs.; 2 figs.

  3. Preparation of EVA/silica nano composites characterized with solid state nuclear magnetic resonance; Obtencao de nanocomposito de EVA/SILICA e caracterizacao por ressonancia magnetica nuclear no estado solido

    Energy Technology Data Exchange (ETDEWEB)

    Passos, Adriano A; Tavares, Maria I.B.; Neto, Roberto C.P.; Moreira, Leonardo A; Ferreira, Antonio G., E-mail: mibt@ima.ufrj.br [Centro de Tecnologia, Instituto de Macromoleculas Professora Eloisa Mano, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ (Brazil)

    2011-07-01

    Nano composites of poly(ethylene-co-vinyl acetate)/silica (SiO{sub 2}) with dimensions of ca. 40 nm were prepared via solution intercalation employing chloroform as a solvent. They were mainly characterized with nuclear magnetic resonance spectroscopy (NMR) employing carbon-13 (polymeric matrix), silicon-29 (nanoparticles) and through the determination of the proton spin-lattice relaxation time in the rotating frame (T{sub 1{rho}H}) (polymer matrix). From the NMR results it was inferred that up to 5% of silica in mass a well dispersed nano composite was obtained, owing to a strong interaction between silica and the EVA matrix. (author)

  4. Parametri za procena na kvalitetot na polietilenska i na polipropilenska ambalaza i na gumeni zatvoraci nameneti za farmacevtski preparati

    Directory of Open Access Journals (Sweden)

    Liljana Ugrinova

    2002-03-01

    Full Text Available Napraven e pregled na parametrite za procena na kvalitetot na polietilenska i na polipropilenska ambalaza i na gumeni zatvoraci nameneti za farmacevtski preparati. Za procena na kvalitetot na ispituvaniot materijal bea izvrseni fizicki, hemiski i bioloski ispituvanja spored postapkite dadeni vo Ph. Eur., DIN i spored DIN ISO standardite. Baranjata za kvalitet na ovoj vid ambalaza propisani spored Ph. Eur., DIN i DIN ISO standardite se razlikuvaat vo odnos na predvidenite parametri za fizicki, za hemiski i za bioloski ispituvanja. Isto taka, propisani se i razlicni granici na dozvoleno otstapuvanje na oddelni parametri.

  5. Characterisation, repackaging and incineration of NaK and Na used for heat transfer experiences on LMFBR at the JRC-Ispra site

    Energy Technology Data Exchange (ETDEWEB)

    Mazzuccato, M.; D' Alberti, F.; D' Amati, F. [European Commission, Joint Research Centre, Nuclear Decommissioning Unit, Via Fermi 210207 Ispra VA (Italy)

    2010-07-01

    The Joint Research Centre (JRC) is a service of the European Commission and its mission is to provide scientific and technical support to the EU policies. At the Italian JRC Ispra site is currently ongoing a nuclear decommissioning program aimed at dismantling and disposing facilities and materials no longer used for nuclear research purposes, e.g. alkali metals, whose radioactive content has to be checked prior the disposal as radioactive or conventional waste. This paper describes the project phases consisting in characterising, repackaging and disposing of {approx}607 kg of alkali metals, composed by {approx}397 kg of NaK liquid alloy and {approx}210 kg of Na metal. The material was used in the past for scientific experiences on heat transfer for liquid metal fast breeder reactors. The alkali metals are very reactive in presence of water leading to the formation of hydrogen; moreover the NaK had been stored for several years in a bunker inside drums unable to guarantee the needed confinement, with the consequent formation of oxygenated compounds in the outer layer of the alloy crust, as Na{sub 2}O{sub 2}, NaO{sub 2}, K{sub 2}O{sub 2} and KO{sub 2}, unstable if moved in presence of the liquid substrate. To perform the characterization and repackaging operations in a safe manner, avoiding any possible reaction between the liquid alloy and the solid surface of oxides, the alloy has been solidified reducing bunker temperature down to the alloy melting point (-15 deg. C). The sampling has been carried out by means of glove bag sealed on the top of each drum and filled in with inert gas to reduce the presence of humidity. Having characterization campaign proved that the alkali metals could not be classified as radioactive material, the NaK and Na containers were shipped to UK in a refrigerated truck. In order to allow a safe thermal destruction in a conventional incineration plant, additional repackaging has been performed in a UK plant to reduce the amount of alkali

  6. [Nuclear matrix organization of the chromocenters in cultured murine fibroblasts].

    Science.gov (United States)

    Sheval', E V; Poliakov, V Iu

    2010-01-01

    In the current work, the structural organization of nuclear matrix of pericentromeric heterochromatin blocks (chromocenters) inside cultured murine fibroblasts was investigated. After 2 M NaCl extraction without DNase I treatment, chromocenters were extremely swelled, and it was impossible to detect them using conventional electron microscopy. Using immunogolding with anti-topoisomerase IIalpha antibody, we demonstrated that residual chromocenters were subdivided into numerous discrete aggregates. After 2 M NaCl extraction with DNase I treatment, the residual chromocenters appeared as a dense meshwork of thin fibers, and using this feature, the residual chromocenters were easily distinguished from the rest of nuclear matrix. After extraction with dextran sulfate and heparin, the chromocenters were decondensed, and chromatin complexes having rosette organization (central core from which numerous DNA fibers radiated) were seen. Probably, the appearance of these rosettes was a consequence of incomplete chromatin extraction. Thus, the nuclear matrix of pericentromeric chromosome regions in cultured murine fibroblasts differs morphologically from the rest of nuclear matrix.

  7. Laser-induced nuclear orientation and gamma anisotropy in sodium

    International Nuclear Information System (INIS)

    Pappas, P.G.

    1980-12-01

    The use of laser optical pumping to induce nuclear orientation in several isotopes and one isomer of atomic sodium vapor is described. Essentially complete nuclear polarization, P > 90%, has been achieved in stable 23 Na when pumping with modest laser intensities (I approx. = 10 mW/cm 2 ). The volume of the sample cell was approximately 10 cc, and was filled with a sodium density of about 10'' atoms/cc. Complete coverage of the Doppler distribution was accomplished with the use of trace amounts (less than or equal to 1 torr) of argon buffer gas to induce velocity changing collisions. A theoretical model which accurately predicts the amount of polarization is developed. The orientation of nuclei which are unstable to gamma decay can manifest itself in anisotropic gamma ray emission. This anisotropy can be used to measure isotope and isomer shifts, from which nuclear properties can be derived. Gamma anisotropy was observed in two systems, 22 Na and /sup 24m/Na. From the observed anisotropy in /sup 24m/Na, a negative sign for the g factor is determined. Values are derived for the magnetic moment, μ = 2.56 +- 0.64 nm, and the isomer shift, deltaν/sub 24m/ = 288 +- 191 MHz (D1 line). A model is described which relates various laser and fubber gas parameters to the observed gamma anisotropy lineshape. This model facilitates the extraction of physical parameters from knowledge of the laser frequency at which the anisotropy is a maximum

  8. Magnetic resonance imaging of cerebellar Schistosomiasis mansoni; Ressonancia magnetica na esquistossomose mansoni cerebelar

    Energy Technology Data Exchange (ETDEWEB)

    Braga, Bruno Perocco; Costa Junior, Leodante Batista da [Hospital da Baleia, Belo Horizonte, MG (BRazil). Servico de Neurocirurgia; Lambertucci, Jose Roberto [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Faculdade de Medicina. Servico de Doencas Infecciosas e Parasitarias

    2003-10-01

    A 15-year-old boy was admitted to hospital with a history of headache, dizziness, vomiting and double vision that started two weeks before. His parents denied any previous disease. During clinical examination he presented diplopia on lateral gaze to the left and horizontal nystagmus. No major neurological dysfunction was detected. He was well built, mentally responsive and perceptive. Laboratory findings revealed a leukocyte count of 10,000/mL, a normal red blood cell count and no eosinophilia. The magnetic resonance images (MRI) of the brain showed a left cerebellar lesion with mass effect compressing the surrounding tissues. Contrast-enhanced images showed a mass like structure and punctate nodules (Figures A and B: axial and coronal contrast-enhanced T1-weighted MR images showed the nodular - yellow arrows - enhancement pattern of a left cerebellar intraxial lesion). The lesion extended to the vermis and brachium pons and compressed the medulla. There was no hydrocephalus. He was taken to the operating room with the presumptive diagnosis of a neuroglial tumor, and submitted to a lateral suboccipital craniectomy. A brown, brittle tumoral mass without a clearly defined margin with the cerebellar tissue was removed. Microscopic examination revealed schistosomal granulomas in the productive phase in the cerebellum (Figure C). After surgery, treatment with praziquantel (50 mg/kg/dia, single dose) and prednisone (1 mg/kg/day) was offered and the patient improved quickly. Thirty days later he was seen again at the outpatient clinic: he was asymptomatic and with no neurological impairment. This is the eighth case of cerebellar involvement in schistosomiasis mansoni and the second report of a tumoral form of cerebellar schistosomiasis documented by magnetic resonance images. (author)

  9. International law and arms control: Soviet Union and Russia’s stance on nuclear test ban treaties

    Directory of Open Access Journals (Sweden)

    Renata Hessmann Dalaqua

    2013-12-01

    Full Text Available The long-lasting struggle against nuclear tests can be examined through different perspectives. In this paper, the focus will be on the part played by the USSR and Russia in the international efforts aimed at establishing legal instruments to outlaw nuclear explosions in space, underground, under water and in the atmosphere.  A luta contra os testes nucleares pode ser examinada sob diferentes perspectivas. Aqui, o foco recairá sobre o papel desempenhado pela União Soviética e Rússia na criação de instrumentos legais para proibir explosões nucleares no espaço, no subsolo, debaixo da água e na atmosfera.

  10. Contamination monitoring of Na 131 I levels in therapy unit of Research Institute for Nuclear Medicine, Tehran University of Medical Sciences by indirect method (Wipe test)

    International Nuclear Information System (INIS)

    Beiki, D.; Shahhosseini, S.; Eftekhari, M.; Takavar, A.; Fard-Esfahani, A.

    2003-01-01

    Contamination with radiopharmaceuticals in nuclear medicine centres in addition to being a health concern requires time consuming decontamination efforts. According to Nuclear Regulatory Commission Contamination should be monitored in nuclear medicine centers where radiopharmaceuticals are prepared and administrated at the end of each working session; otherwise, contamination spread to other areas not only equipment but also personnel and other people will be expected. The wipe test for the presence of radioactivity is accomplished by wiping the surface over an area approximately 100 cm 2 with an absorbent paper, then counting it in an appropriate radiation detector. In this study, contamination monitoring of patient's rooms (4 rooms), entrance corridor, patient's corridor, waiting room, control room (nursing station), radiopharmaceutical storage room in therapy unit of Research Institute for Nuclear Medicine, Shariati hospital was performed by indirect method. Based on the results, some areas including storage room were contaminated. There was also a direct relationship between dose administrated and levels of contamination in patient's rooms. Regarding high uptake of iodine by thyroid gland and damaging effects of Na 131 I, weekly wipe tests are required to determine the level of contamination. Patient's rooms after discharging the patients and before re hospitalization specially should be checked. If these tests reveal contamination over standard levels, appropriate decontamination procedures should be carried out immediately

  11. Occurrence of /sup 22/Na in some species of Canadian biota

    Energy Technology Data Exchange (ETDEWEB)

    Guthrie, J E

    1965-09-01

    Cosmic-ray spallation of argon and fallout from testing of high-yield nuclear weapons have increased the amount of /sup 22/Na present in the environment. Consequently, it has been possible to measure /sup 22/Na in Alaskan natives, caribou, elk, and some foods. Samples of flora and fauna were routinely collected in the vicinity of Pinawa, Manitoba, as a part of the Whiteshell Nuclear Research Establishment's radiation survey program. Gamma spectrometric analysis methods revealed the presence of /sup 22/Na in samples taken during 1964, in addition to other long-lived fission products such as /sup 144/Ce, /sup 125/Sb, /sup 106/Ru, /sup 137/Cs, and /sup 54/Mn. Sodium-22 was measured in samples of muscle tissue taken from the red squirrel (Tamiasciurus sp.) and hare (Lepus americanus), but was not detected in the flesh of the short-tailed weasel (Mustela erminea). Sodium-22 was detected neither in the sweet (white) clover which grew profusely in the area where the mammals were trapped nor in composite samples of Winnipeg River water in any of the species of fish taken from the river during this period: rock bass (Amblopletes rupestris), sucker (Castostomus sp.), pike (Esox lucius), pickerel (Stizostedion vitreum), and sauger (Stizostedion canadense). However, /sup 22/Na has been reported in bass caught in the Columbia River, Washington. Potassium-40 and /sup 137/Cs means in the samples examined indicate an apparent increase in the amounts of /sup 137/Cs. The amount of /sup 22/Na measured in rabbits is much less than the maximum permissible body burden for the nuclide (10 ..mu..C).

  12. Studies in Low-Energy Nuclear Science

    Energy Technology Data Exchange (ETDEWEB)

    Carl R. Brune; Steven M. Grimes

    2010-01-13

    This report presents a summary of research projects in the area of low energy nuclear reactions and structure, carried out between March 1, 2006 and October 31, 2009 which were supported by U.S. DOE grant number DE-FG52-06NA26187.

  13. Real-time control of electronic motion: Application to NaI

    DEFF Research Database (Denmark)

    Grønager, Michael; Henriksen, Niels Engholm

    1998-01-01

    + + I- depends on the electron distribution (i.e., where the electron "sits") prior to the time where the bond is broken by a subpicosecond half-cycle unipolar electromagnetic pulse. Thus we control, in real time, which nucleus one of the valence electrons will follow after the bond is broken. (C) 1998......We study theoretically the electronic and nuclear dynamics in NaI. After a femtosecond pulse has prepared a wave packet in the first excited state, we consider the adiabatic and the nonadiabatic electronic dynamics and demonstrate explicitly that a nonstationary electron is created in Na...

  14. Stimulated nuclear spin echos and spectral diffusion in glasses

    International Nuclear Information System (INIS)

    Borges, N.M.; Engelsberg, M.

    1984-01-01

    Experimental results of stimulated nuclear spin echos decay in glasses are presented. The measurements were performed in B 2 O 3 glasses, at the 23Na and 11 B resonance lines. The data analysis allows the study of Spectral diffusion at an inhomogeneous nuclear magnetic (NMR) resonance line, broadened for a desordered system of nuclear spins. A model is proposed to explain the time constants, and the particular form of the decay. (A.C.A.S.) [pt

  15. Assessment of maximal erythrocyte Na sup + , K sup + -ATPase activity in patients with various arterial hypertensions by using sup 23 Na NMR. Otsenka maksimal'noj aktivnosti Na sup + , K sup + -ATFazy v ehritrotsitakh u bol'nykh s razlichnymi formami arterial'noj gipertenzii metodom sup 23 Na-YaMR

    Energy Technology Data Exchange (ETDEWEB)

    Revazov, A V; Knubovets, T L; Sibel' dina, L A; Sumarokov, A V [Pervyj Moskovskij Meditsinskij Inst., Moscow (USSR) AN SSSR, Moscow (USSR). Inst. Khimicheskoj Fiziki

    1990-03-01

    The paper provides measurements of maximal erythrocyte Na{sup +}, K{sup +}-ATPase activity in 20 patients with hypertensive disease, 20 patients with secondary hypertension and 20 healthy donors. The investigation was made by high-resolution nuclear magnetic resonance using sodium nuclei. A significant decrease was found in Na{sup +}, K{sup +}-ATPase activity in the patients with hypertensive disease (9.0{plus minus}0.3 mg-equiv. per liter cells an hour) as compared with those with secondary hypertension (10.3{plus minus}0.3 mg-equiv. per liter cells an hour) and the controls (10.5{plus minus}0.3 mg-equiv. per liter cells an hour), which supports the finding of impaired membrane morphology in hypertensive disease.

  16. Načrtovan porod na domu

    OpenAIRE

    Todorović, Tamara; Takač, Iztok

    2017-01-01

    Izhodišča: Porod na domu je sicer star toliko kot človeštvo, pa vendar v veliki večini srednje in visoko razvitih držav prevladuje mnenje, da so zaradi nepredvidljivosti zapletov porodnišnice najbolj varno okolje za rojevanje. Kljub temu obstaja peščica držav, v katerih je porod na domu integriran v sistem zdravstvenega varstva (npr. Nizozemska, Velika Britanija, Kanada). Pri porodih na domu ločimo nenačrtovane in načrtovane porode na domu, slednje pa lahko nadalje razdelimo še na porode s sp...

  17. Compact device for the extraction of sup(99m)TcO4Na

    International Nuclear Information System (INIS)

    Pliego, O.H.; Mitta, A.E.A.

    1982-01-01

    A non automatic device for the extraction of sup(99m)TcO 4 Na by liquid-liquid extraction method is described. It has been developed at the Laboratory of Labelled Molecules of the CNEA and was installed at the Nuclear Medicine Centre of the Hospital de Clinicas Jose de San Martin. The solutions of sup(99m)TcO 4 Na are used for the labelling of radiopharmaceuticals and also for making radiodiagnosis. (author) [es

  18. Thermogravimetric and nuclear magnetic resonance study of hydrated Na-β''-alumina

    International Nuclear Information System (INIS)

    Donoso, P.; Panepucci, H.; Gobato, Y.G.; Oliveira, L.N.; Souza, D.P.F. de

    1990-01-01

    This paper reports thermogravimetric and proton spin-lattice relaxation times measurement of hydrated Na-β''-alumina, which yield information about the identification of the sites where the loosely bound water molecules are located in the polycrystalline sample. It examines also the influence of impurities on the motion of the protons. (autor) [pt

  19. Development and validation of the ASTEC-Na thermal-hydraulic models

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, L. E.; Perez, S.; Bandini, G.; Jacq, F.; Parisi, C.; Berna, C.

    2014-07-01

    Last years the interest in sodium-cooled fast reactors (SFR) has been fostered worldwide by the search for higher nuclear energy sustainability. This has been reflected in the various international initiatives like GEN-IV International Forum, INPRO or ESNII platforms. At the same time, innovative nuclear reactor designs, particularly SFR, are aiming at even higher safety standards than current LWRs. A proof of it is the consideration of severe accidents since the earliest stages of reactor design. commonalities of LWR and SFR severe accident scenarios suggest that some of the knowledge achieved in the LWR arena might be applicable to some extent to SFRs. This is the spirit underneath of the EU-JASMIN project, which generic goal is developing the ASTEC-Na code from the LWR ASTEC platform. This will entail to t extend and adapt some existing models as well as to implement new ones in all the areas covered, from neutronics and pin thermo-mechanics and pin thermo-mechanics to the in-containment source term behavior by these, going through the indispensable Na thermal-hydraulics. (Author)

  20. A CVD Diamond Detector for (n,a) Cross-Section Measurements

    CERN Document Server

    Weiss, Christina; Griesmayer, Erich; Guerrero, Carlos

    A novel detector based on the chemical vapor deposition (CVD) diamond technology has been developed in the framework of this PhD, for the experimental determination of (n,a) cross-sections at the neutron time-of-flight facility n_TOF at CERN. The 59Ni(n,a)56Fe cross-section, which is relevant for astrophysical questions as well as for risk-assessment studies in nuclear technology, has been measured in order to validate the applicability of the detector for such experiments. The thesis is divided in four parts. In the introductory part the motivation for measuring (n,a) cross-sections, the experimental challenges for such measurements and the reasons for choosing the CVD diamond technology for the detector are given. This is followed by the presentation of the n_TOF facility, an introduction to neutron-induced nuclear reactions and a brief summary of the interaction of particles with matter. The CVD diamond technology and the relevant matters related to electronics are given as well in this first part of the t...

  1. Significance and outcome of nuclear anaplasia and mitotic index in prostatic adenocarcinomas.

    Science.gov (United States)

    Kır, Gozde; Sarbay, Billur Cosan; Gumus, Eyup

    2016-10-01

    The Gleason grading system measures architectural differentiation and disregards nuclear atypia and the cell proliferation index. Several studies have reported that nuclear grade and mitotic index (MI) are prognostically useful. This study included 232 radical prostatectomy specimens. Nuclear anaplasia (NA) was determined on the basis of nucleomegali (at least 20µm); vesicular chromatin; eosinophilic macronucleoli, nuclear lobulation, and irregular thickened nuclear membranei. The proportion of area of NA was recorded in each tumor in 10% increments. The MI was defined as the number of mitotic figures in 10 consecutive high-power fields (HPF). In univariate analysis, significant differences included associations between biochemical prostate-specific antigen recurrence (BCR) and Gleason score, extraprostatic extension, positive surgical margin, the presence of high-pathologic stage, NA≥10% of tumor area, MI≥3/10 HPF, and preoperative prostate-specific antigen. In a stepwise Cox regression model, a positive surgical margin, the presence of a NA≥10% of tumor area, and a MI of≥3/10 HPF were independent predictors of BCR after radical prostatectomy. NA≥10% of tumor area appeared to have a stronger association with outcome than MI≥3/10 HPF, as still associated with BCR when Gleason score was in the model. The results of our study showed that, in addition to the conventional Gleason grading system, NA, and MI are useful prognostic parameters while evaluating long-term prognosis in prostatic adenocarcinoma. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Use of microcontroller in gamma-ray spectrometer construction using NaI(Tl) sensor, with emphasis in multichannel analyzer, to applications in nuclear and environmental geophysics; Uso de microcontrolador na construcao de espectrometro gama com sensor de NaI(Tl), com enfase em analisador multicanal, para aplicacao em geofisica nuclear e ambiental

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Nilton

    2005-07-01

    In this work of nuclear geophysical instrumentation the main purpose was the development of a gamma-ray spectrometer prototype with multi channel analyzer, since the spectroscopic amplifier until your firmware. The heart of the digital part was an ATMEL 8 bits microcontroller (AT89S8252). All circuits were made and assembled in the Laboratory of Applied Geophysical Instrumentation (LIGA) of IAG-USP. A microcontroller software was completely developed in C ANSI language using the Small Device C Compiler version 2.4.8, that is a free software distributed under General Public License (GPL). At first, microcontroller was used to change all digital circuit of one classic SCINTREX GAD-6 differential gamma-ray spectrometer. Measurement times with order of 2 days became possible, and it could work in non climate ambient. Then, after this stage, had been started the development of a multichannel analyzer (MCA) working in pulse height analyzer mode with 4096 channels capacity, to use in many kinds of nuclear detection. Besides it, was developed an automatic gain system for photopeak stabilization, by the use of one radioactive source ({sup 133}Ba). This automatic gain system is very important in the case of NaI(Tl) scintillometric detectors, due PMT sensitivity with temperature and aging of some laboratory electronic circuits. Two power supplies with high stability, using pulse width modulation (PWM) techniques were developed, in order to all system became free of electrical line break off. One PWM power polarizes a photo multiplier tube (PMT) with high voltage and another supplies remaining developed circuits. Calibration in energy using standards sources {sup 137}Cs and {sup 60}Co showed that gamma detector developed has a good linearity and low thermal drift, even working in absent of air-conditioned. Concentrations measurements of K, U and Th were made in samples of soils, vegetables, etc. (author)'

  3. Design, Fabrication and Integration of a NaK-Cooled Circuit

    International Nuclear Information System (INIS)

    Garber, Anne; Godfroy, Thomas

    2006-01-01

    The Early Flight Fission Test Facilities (EFF-TF) team has been tasked by the NASA Marshall Space Flight Center Nuclear Systems Office to design, fabricate, and test an actively pumped alkali metal flow circuit. The system, which was originally designed for use with a eutectic mixture of sodium potassium (NaK), was redesigned for use with lithium. Due to a shift in focus, it is once again being prepared for use with NaK. Changes made to the actively pumped, high temperature circuit include the replacement of the expansion reservoir, addition of remotely operated valves, and modification of the support table. Basic circuit components include: reactor segment, NaK to gas heat exchanger, electromagnetic (EM) liquid metal pump, load/drain reservoir, expansion reservoir, instrumentation, and a spill reservoir. A 37-pin partial-array core (pin and flow path dimensions are the same as those in a full design) was selected for fabrication and test. This paper summarizes the integration and preparations for the fill of the pumped NaK circuit. (authors)

  4. Section for nuclear physics annual report

    International Nuclear Information System (INIS)

    1989-04-01

    The experimental activities in nuclear physics have in 1988 mainly been centered around the cyclotron laboratory with the SCANDITRONIX MC-35 cyclotron. The CACTUS multidetector system has been realised and will soon be operating. With 8 particle telescopes, 28 NaI detectors and 2 Ge detectors this experimental arrangement represents a major improvement compared to earlier set-ups in the laboratory. Theoretical studies of many-body problems, nuclear structure and reactions have continued. The study of problems related to the foundations of quantum mechanics has also been persued

  5. Nuclear Overhauser effect studies of the conformation of Co(NH3)4ATP bound to kidney Na,K-ATPase

    International Nuclear Information System (INIS)

    Stewart, J.M.; Jorgensen, P.L.; Grisham, C.M.

    1989-01-01

    Transferred nuclear Overhauser effect measurements (in the two-dimensional mode) have been used to determine the three-dimensional conformation of an ATP analogue, Co(NH3)4ATP, at the active site of sheep kidney Na,K-ATPase. Previous studies have shown that Co(NH3)4ATP is a competitive inhibitor with respect to MnATP for the Na,K-ATPase. Nine unique proton-proton distances on ATPase-bound Co(NH3)4ATP were determined from the initial build-up rates of the cross-peaks of the 2D-TRNOE data sets. These distances, taken together with previous 31P and 1H relaxation measurements with paramagnetic probes, are consistent with a single nucleotide conformation at the active site. The bound (Co(NH3)4ATP) adopts an anti conformation, with a glycosidic torsion angle of 35 degrees, and the conformation of the ribose ring is slightly N-type (C2'-exo, C3'-endo). The delta and gamma torsional angles in this conformation are 100 degrees and 178 degrees, respectively. The nucleotide adopts a bent configuration, in which the triphosphate chain lies nearly parallel to the adenine moiety. Mn2+ bound to a single, high-affinity site on the ATPase lies above and in the plane of the adenine ring. The distances from enzyme-bound Mn2+ to N6 and N7 are too large for first coordination sphere complexes, but are appropriate for second-sphere complexes involving, for example, intervening hydrogen-bonded water molecules. The NMR data also indicate that the structure of the bound ATP analogue is independent of the conformational state of the enzyme

  6. Nuclear Overhauser effect studies of the conformation of Co(NH3)4ATP bound to kidney Na,K-ATPase

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, J.M.; Jorgensen, P.L.; Grisham, C.M. (Univ. of Virginia, Charlottesville (USA))

    1989-05-30

    Transferred nuclear Overhauser effect measurements (in the two-dimensional mode) have been used to determine the three-dimensional conformation of an ATP analogue, Co(NH3)4ATP, at the active site of sheep kidney Na,K-ATPase. Previous studies have shown that Co(NH3)4ATP is a competitive inhibitor with respect to MnATP for the Na,K-ATPase. Nine unique proton-proton distances on ATPase-bound Co(NH3)4ATP were determined from the initial build-up rates of the cross-peaks of the 2D-TRNOE data sets. These distances, taken together with previous 31P and 1H relaxation measurements with paramagnetic probes, are consistent with a single nucleotide conformation at the active site. The bound (Co(NH3)4ATP) adopts an anti conformation, with a glycosidic torsion angle of 35{degrees}, and the conformation of the ribose ring is slightly N-type (C2'-exo, C3'-endo). The delta and gamma torsional angles in this conformation are 100 degrees and 178 degrees, respectively. The nucleotide adopts a bent configuration, in which the triphosphate chain lies nearly parallel to the adenine moiety. Mn2+ bound to a single, high-affinity site on the ATPase lies above and in the plane of the adenine ring. The distances from enzyme-bound Mn2+ to N6 and N7 are too large for first coordination sphere complexes, but are appropriate for second-sphere complexes involving, for example, intervening hydrogen-bonded water molecules. The NMR data also indicate that the structure of the bound ATP analogue is independent of the conformational state of the enzyme.

  7. Nuclear techniques in agriculture

    International Nuclear Information System (INIS)

    Bhagwat, S.G.

    2012-01-01

    Crops provide us food grains and many other products. Demand for food and other agricultural products is increasing. There is also need for improvement of quality of the agricultural produce. There are several technologies in use for achieving the goal of increasing the quantity and quality of agricultural produce. Nuclear techniques provide us with an option which has certain advantages. The characteristics of crop plants are determined by the genetic make up of the plant. Traditionally the genetic make up was modified using conventional breeding techniques such as cross breeding to improve crops for yield, disease resistance, stress tolerance, resistance to insect pests or to improve quality. New varieties of crops are produced which replace the earlier ones and thus the demands are met. The process of development of new varieties is long and time consuming. Nuclear technique called mutation breeding provides an efficient way of breeding new varieties or improving the older ones. This technique merely enhances the process of occurrence of mutations. In nature mutations occur at a rate of approximately one in a million, while when mutations are induced using radiations such as gamma rays the efficiency of inducing mutations is enhanced. Useful mutations are selected, the mutants are evaluated and developed as a new variety. In the Nuclear Agriculture and Biotechnology Division (NA and BTD) this technique has been used to develop mutants of many crop plants. The mutants can be used to develop a variety directly or by using it in further breeding programme. Using these approaches the NA and BTD has developed 40 new varieties of crops such as groundnut, mungbean, urid, pigeon pea, mustard, soybean, sunflower, cowpea, jute. These varieties are developed in collaboration with other agricultural institutions and are popular among the farming community. The method of mutation breeding can be applied to many other crops for improvement. There is increasing interest among

  8. Prediction of Intrinsic Cesium Desorption from Na-Smectite in Mixed Cation Solutions.

    Science.gov (United States)

    Fukushi, Keisuke; Fukiage, Tomo

    2015-09-01

    Quantitative understanding of the stability of sorbed radionuclides in smectite is necessary to assess the performance of engineering barriers used for nuclear waste disposal. Our previous study demonstrated that the spatial organization of the smectite platelets triggered by the divalent cations led to the apparent fixation of intrinsic Cs in smectite, because some Cs is retained inside the formed tactoids. Natural water is usually a mixture of Na(+) and divalent cations (Ca(2+) and Mg(2+)). This study therefore investigated the desorption behavior of intrinsic Cs in Na-smecite in mixed Na(+)-divalent cation solutions under widely various cation concentrations using batch experiments, grain size measurements, and cation exchange modeling (CEM). Results show that increased Na(+) concentrations facilitate Cs desorption because Na(+) serves as the dispersion agent. A linear relation was obtained between the logarithm of the Na(+) fraction and the accessible Cs fraction in smectite. That relation enables the prediction of accessible Cs fraction as a function of solution cationic compositions. The corrected CEM considering the effects of the spatial organization suggests that the stability of intrinsic Cs in the smectite is governed by the Na(+) concentration, and suggests that it is almost independent of the concentrations of divalent cations in natural water.

  9. Enhanced nuclear magnetic resonance in a non-magnetic cubic doublet

    International Nuclear Information System (INIS)

    Veenendaal, E.J.

    1982-01-01

    In this thesis two lanthanide compounds are studied which show enhanced nuclear magnetism at low temperatures: Rb 2 NaHoF 6 and CsNaHoF 6 . Chapter II gives a description of the 4 He-circulating refrigerator, which was built to provide the low temperatures required for the polarization of the enhanced nuclear moments. This type of dilution refrigerator was chosen because of its simple design and large cooling power. Chapter III is devoted to a comparison of the different types of dilution refrigerators. A theoretical discussion is given of their performance, starting from the differential equations, which govern the temperature distribution in the refrigerator. In chapter IV the actual performance of the refrigerator, described in chapter II is discussed. In chapter V a description of the NMR-apparatus, developed for very-low-temperature NMR experiments is given. In chapter VI experimental results on the compound Rb 2 NaHoF 6 are presented. The CEF-ground state of this compound is probably the non-magnetic doublet GAMMA 3 , but at a temperature of 170 K a structural phase transition lowers the crystal symmetry from cubic to tetragonal and the doublet is split into two singlets. In chapter VII specific heat, (enhanced) nuclear magnetic resonance and magnetization measurements on the compound Cs 2 NaHoF 6 are presented which also has a GAMMA 3 -doublet ground state. In zero magnetic field the degeneracy of the doublet is removed at a temperature of 393 mK, where a phase transition is induced by quadrupolar interactions. (Auth.)

  10. Effect of TGFβ on Na{sup +}/K{sup +} ATPase activity in megakaryocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hosseinzadeh, Zohreh; Schmid, Evi; Shumilina, Ekaterina [Department of Physiology, University of Tübingen (Germany); Laufer, Stefan [Pharmaceutical Chemistry, University of Tübingen (Germany); Borst, Oliver; Gawaz, Meinrad [Cardiology and Cardiovascular Medicine, University of Tübingen (Germany); Lang, Florian, E-mail: florian.lang@uni-tuebingen.de [Department of Physiology, University of Tübingen (Germany)

    2014-09-26

    Highlights: • TGFß1 markedly up-regulates Na{sup +}/K{sup +} ATPase in megakaryocytes. • The effect is abrogated by p38-MAP kinase inhibitor skepinone. • The effect is abrogated by SGK inhibitor EMD638683. • The effect is abrogated by NF-κB inhibitor wogonin. - Abstract: The Na{sup +}/K{sup +} ATPase generates the Na{sup +} and K{sup +} concentration gradients across the plasma membrane and is thus essential for cellular electrolyte homeostasis, cell membrane potential and cell volume maintenance. A powerful regulator of Na{sup +}/K{sup +} ATPase is the serum- and glucocorticoid-inducible kinase 1 (SGK1). The most powerful known regulator of SGK1 expression is TGFß1, which is pivotal in the regulation of megakaryocyte maturation and platelet formation. Signaling involved in the upregulation of SGK1 by TGFß1 includes p38 mitogen activated protein (MAP) kinase. SGK1 in turn phosphorylates the IκB kinase (IKKα/β), which phosphorylates the inhibitor protein IκBα thus triggering nuclear translocation of nuclear factor kappa B (NF-κB). The present study explored whether TGFβ influences Na{sup +}/K{sup +} ATPase activity in megakaryocytes, and if so, whether the effect of TGß1 requires p38 MAP kinase, SGK1 and/or NF-κB. To this end, murine megakaryocytes were treated with TGFß1 and Na{sup +}/K{sup +} ATPase activity determined from K{sup +} induced current utilizing whole cell patch clamp. The pump current (I{sub pump}) was determined in the absence and presence of Na{sup +}/K{sup +} ATPase inhibitor ouabain (100 μM). TGFß1 (60 ng/ml) was added in the absence or presence of p38 MAP kinase inhibitor skepinone-L (1 μM), SGK1 inhibitor EMD638683 (50 μM) or NF-κB inhibitor wogonin (50 nM). As a result, the I{sub pump} was significantly increased by pretreatment of the megakaryocytes with TGFß1, an effect reaching statistical significance within 16 and 24 h and virtually abrogated in the presence of skepinone-L, EMD638683 or wogonin. In conclusion

  11. Fast molten salt reactor-transmuter for closing nuclear fuel cycle on minor actinides

    International Nuclear Information System (INIS)

    Dudnikov, A. A.; Alekseev, P. N.; Subbotin, S. A.

    2007-01-01

    Creation fast critical molten salt reactor for burning-out minor actinides and separate long-living fission products in the closed nuclear fuel cycle is the most perspective and actual direction. The reactor on melts salts - molten salt homogeneous reactor with the circulating fuel, working as burner and transmuter long-living radioactive nuclides in closed nuclear fuel cycle, can serve as an effective ecological cordon from contamination of the nature long-living radiotoxic nuclides. High-flux fast critical molten-salt nuclear reactors in structure of the closed nuclear fuel cycle of the future nuclear power can effectively burning-out / transmute dangerous long-living radioactive nuclides, make radioisotopes, partially utilize plutonium and produce thermal and electric energy. Such reactor allows solving the problems constraining development of large-scale nuclear power, including fueling, minimization of radioactive waste and non-proliferation. Burning minor actinides in molten salt reactor is capable to facilitate work solid fuel power reactors in system NP with the closed nuclear fuel cycle and to reduce transient losses at processing and fabrications fuel pins. At substantiation MSR-transmuter/burner as solvents fuel nuclides for molten-salt reactors various salts were examined, for example: LiF - BeF2; NaF - LiF - BeF2; NaF-LiF ; NaF-ZrF4 ; LiF-NaF -KF; NaCl. RRC 'Kurchatov institute' together with other employees have developed the basic design reactor installations with molten salt reactor - burner long-living nuclides for fluoride fuel composition with the limited solubility minor actinides (MAF3 10 mol %) allows to develop in some times more effective molten salt reactor with fast neutron spectrum - burner/ transmuter of the long-living radioactive waste. In high-flux fast reactors on melts salts within a year it is possible to burn ∼300 kg minor actinides per 1 GW thermal power of reactor. The technical and economic estimation given power

  12. The U.S./IAEA Workshop on Software Sustainability for Safeguards Instrumentation: Report to the NNSA DOE Office of International Nuclear Safeguards (NA-241)

    Energy Technology Data Exchange (ETDEWEB)

    Pepper, Susan E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pickett, Chris A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Queirolo, Al [Brookhaven National Lab. (BNL), Upton, NY (United States); Bachner, Katherine M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Worrall, Louise G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-04-07

    The U.S Department of Energy (DOE) National Nuclear Security Administration (NNSA) Next Generation Safeguards Initiative (NGSI) and the International Atomic Energy Agency (IAEA) convened a workshop on Software Sustainability for Safeguards Instrumentation in Vienna, Austria, May 6-8, 2014. Safeguards instrumentation software must be sustained in a changing environment to ensure existing instruments can continue to perform as designed, with improved security. The approaches to the development and maintenance of instrument software used in the past may not be the best model for the future and, therefore, the organizers’ goal was to investigate these past approaches and to determine an optimal path forward. The purpose of this report is to provide input for the DOE NNSA Office of International Nuclear Safeguards (NA-241) and other stakeholders that can be utilized when making decisions related to the development and maintenance of software used in the implementation of international nuclear safeguards. For example, this guidance can be used when determining whether to fund the development, upgrade, or replacement of a particular software product. The report identifies the challenges related to sustaining software, and makes recommendations for addressing these challenges, supported by summaries and detailed notes from the workshop discussions. In addition the authors provide a set of recommendations for institutionalizing software sustainability practices in the safeguards community. The term “software sustainability” was defined for this workshop as ensuring that safeguards instrument software and algorithm functionality can be maintained efficiently throughout the instrument lifecycle, without interruption and providing the ability to continue to improve that software as needs arise.

  13. The U.S./IAEA Workshop on Software Sustainability for Safeguards Instrumentation: Report to the NNSA DOE Office of International Nuclear Safeguards (NA-241)

    International Nuclear Information System (INIS)

    Pepper, Susan E.; Pickett, Chris A.; Queirolo, Al; Bachner, Katherine M.; Worrall, Louise G.

    2015-01-01

    The U.S Department of Energy (DOE) National Nuclear Security Administration (NNSA) Next Generation Safeguards Initiative (NGSI) and the International Atomic Energy Agency (IAEA) convened a workshop on Software Sustainability for Safeguards Instrumentation in Vienna, Austria, May 6-8, 2014. Safeguards instrumentation software must be sustained in a changing environment to ensure existing instruments can continue to perform as designed, with improved security. The approaches to the development and maintenance of instrument software used in the past may not be the best model for the future and, therefore, the organizers' goal was to investigate these past approaches and to determine an optimal path forward. The purpose of this report is to provide input for the DOE NNSA Office of International Nuclear Safeguards (NA-241) and other stakeholders that can be utilized when making decisions related to the development and maintenance of software used in the implementation of international nuclear safeguards. For example, this guidance can be used when determining whether to fund the development, upgrade, or replacement of a particular software product. The report identifies the challenges related to sustaining software, and makes recommendations for addressing these challenges, supported by summaries and detailed notes from the workshop discussions. In addition the authors provide a set of recommendations for institutionalizing software sustainability practices in the safeguards community. The term ''software sustainability'' was defined for this workshop as ensuring that safeguards instrument software and algorithm functionality can be maintained efficiently throughout the instrument lifecycle, without interruption and providing the ability to continue to improve that software as needs arise.

  14. Real-time high-resolution X-ray imaging and nuclear magnetic resonance study of the hydration of pure and Na-doped C3A in the presence of sulfates

    KAUST Repository

    Kirchheim, A. P.

    2011-02-21

    This study details the differences in real-time hydration between pure tricalcium aluminate (cubic C3A or 3CaO·Al2O 3) and Na-doped tricalcium aluminate (orthorhombic C3A or Na2Ca8Al6O18), in aqueous solutions containing sulfate ions. Pure phases were synthesized in the laboratory to develop an independent benchmark for the reactions, meaning that their reactions during hydration in a simulated early age cement pore solution (saturated with respect to gypsum and lime) were able to be isolated. Because the rate of this reaction is extremely rapid, most microscopy methods are not adequate to study the early phases of the reactions in the early stages. Here, a high-resolution full-field soft X-ray imaging technique operating in the X-ray water window, combined with solution analysis by 27Al nuclear magnetic resonance (NMR) spectroscopy, was used to capture information regarding the mechanism of C3A hydration during the early stages. There are differences in the hydration mechanism between the two types of C3A, which are also dependent on the concentration of sulfate ions in the solution. The reactions with cubic C3A (pure) seem to be more influenced by higher concentrations of sulfate ions, forming smaller ettringite needles at a slower pace than the orthorhombic C3A (Na-doped) sample. The rate of release of aluminate species into the solution phase is also accelerated by Na doping. © 2011 American Chemical Society.

  15. Manchester nuclear physics report

    International Nuclear Information System (INIS)

    1989-01-01

    This report describes the experimental research of the Manchester University Nuclear Physics Group for the period August 1987 - December 1988. The experiments have been performed at the Daresbury Nuclear Structure Facility, mostly using the gamma-ray arrays and the Recoil Separator. However, experiments using the Daresbury Isotope Separator, the Oxford Folded Tandem and the new charged particle detector array are also reported. Studies of gamma decaying states in 21 Ne and 23 Na are reported. The spectroscopy of medium mass nuclei includes the investigation of the Gamow-Tellar decay of 98 Cd. Fourteen studies of the spectroscopy of nuclei with A ≥ 100 are reported. Fission studies and instrumentation and computer developments are also included. (U.K.)

  16. Securing a better future for all: Nuclear techniques for global development and environmental protection. NA factsheet on nuclear physics: Facilitating the peaceful and practical uses of nuclear science

    International Nuclear Information System (INIS)

    2012-01-01

    When properly applied, nuclear science - the study of atomic nuclei and other subatomic particles - can contribute in many ways to the health, development and security of communities around the world. In this context, the IAEA plays an important role in helping interested Member States develop the capabilities and infrastructure necessary to manage their own programmes devoted to nuclear and radiological applications. The IAEA's nuclear science programme helps Member States to establish sound frameworks for the efficient, safe and secure use of new nuclear technologies, including accelerator facilities, research reactors and future nuclear fusion facilities. By applying nuclear technologies in a wide variety of areas such as energy production, health care, food and agriculture, industry and the environment, Member States can benefit immensely from the ensuing socioeconomic developments, as well as providing better living conditions for their citizens.

  17. Corrosion of simulated nuclear waste glass

    International Nuclear Information System (INIS)

    Music, S.; Ristic, M.; Gotic, M.; Foric, J.

    1988-01-01

    In this study the preparation and characterization of borosilicate glasses of different chemical composition were investigated. Borosilicate glasses were doped with simulated nuclear waste oxides. The chemical corrosion in water of these glasses was followed by measuring the leach rates as a function of time. It was found that a simulated nuclear waste glass with the chemical composition (weight %), 15.61% Na 2 O, 10.39% B 2 O 3 , 45.31% SiO 2 , 13.42% ZnO, 6.61% TiO 2 and 8.66% waste oxides, is characterized by low melting temperature and with good corrosion resistance in water. Influence of passive layers on the leaching behaviour of nuclear waste glasses is discussed. (author) 20 refs.; 7 figs.; 4 tabs

  18. Results on leptonic probes from NA50

    CERN Document Server

    Alessandro, B; Arnaldi, R; Atayan, M; Baglin, C; Baldit, A; Bedjidian, Marc; Beolè, S; Boldea, V; Bordalo, P; Borenstein, S R; Borges, G; Bussière, A; Capelli, L; Castanier, C; Castor, J I; Chaurand, B; Cheynis, B; Chiavassa, E; Cicalò, C; Claudino, T; Comets, M P; Constantinescu, S; Cortese, P; Cruz, J; De Falco, A; De Marco, N; Dellacasa, G; Devaux, A; Dita, S; Drapier, O; Espagnon, B; Fargeix, J; Force, P; Gallio, M; Gavrilov, Yu K; Gerschel, C; Giubellino, P; Golubeva, M B; Gonin, M; Grigorian, A A; Grigorian, S; Grossiord, J Y; Guber, F F; Guichard, A; Gulkanian, H R; Hakobyan, R S; Haroutunian, R; Idzik, M; Jouan, D; Karavitcheva, T L; Kluberg, L; Kurepin, A B; Le Bornec, Y; Lourenço, C; Macciotta, P; MacCormick, M; Marzari-Chiesa, A; Masera, M; Masoni, A; Monteno, M; Musso, A; Petiau, P; Piccotti, A; Pizzi, J R; Prado da Silva, W L; Prino, F; Puddu, G; Quintans, C; Ramello, L; Ramos, S; Rato-Mendes, P; Riccati, L; Romana, A; Santos, H; Saturnini, P; Scalas, E; Scomparin, E; Serci, S; Shahoyan, R; Sigaudo, F; Sitta, M; Sonderegger, P; Tarrago, X; Topilskaya, N S; Usai, G L; Vercellin, Ermanno; Villatte, L; Willis, N; Wu, T

    2003-01-01

    The NA50 Collaboration has performed a new measurement of the J/ psi yield in Pb-Pb collisions at 158 GeV/nucleon in improved experimental conditions. Our preliminary analysis of the year 2000 data sample, while confirming the onset of anomalous suppression and the non saturation of the J/ psi /Drell-Yan cross-section ratio, shows that peripheral Pb-Pb interactions follow the normal nuclear absorption pattern, which has in turn been established more precisely thanks to high statistics p-A data. (11 refs).

  19. Functionalized NaA nanozeolites labeled with 224,225Ra for targeted alpha therapy.

    Science.gov (United States)

    Piotrowska, Agata; Leszczuk, Edyta; Bruchertseifer, Frank; Morgenstern, Alfred; Bilewicz, Aleksander

    2013-01-01

    The 223 Ra, 224 Ra, and 225 Ra radioisotopes exhibit very attractive nuclear properties for application in radionuclide therapy. Unfortunately the lack of appropriate bifunctional ligand for radium is the reason why these radionuclides have not found application in receptor-targeted therapy. In the present work, the potential usefulness of the NaA nanozeolite as a carrier for radium radionuclides has been studied. 224 Ra and 225 Ra, α-particle emitting radionuclides, have been absorbed in the nanometer-sized NaA zeolite (30-70 nm) through simple ion exchange. 224,225 Ra-nanozeolites exhibited very high stability in solutions containing physiological salt, EDTA, amino acids, and human serum. To make NaA nanozeolite particles dispersed in water their surface was modified with a silane coupling agent containing poly(ethylene glycol) molecules. This functionalization approach let us covalently attach a biomolecule to the NaA nanozeolite surface.

  20. Evidence that Na+-pumping occurs through the D-channel in Vitreoscilla cytochrome bo

    International Nuclear Information System (INIS)

    Kim, Seong K.; Stark, Benjamin C.; Webster, Dale A.

    2005-01-01

    The operon (cyo) encoding the Na + -pumping respiratory terminal oxidase (cytochrome bo) of the bacterium Vitreoscilla was transformed into Escherichia coli GV100, a deletion mutant of cytochrome bo. This was done for the wild type operon and five mutants in three conserved Cyo subunit I amino acids known to be crucial for H + transport in the E. coli enzyme, one near the nuclear center, one in the K-channel, and one in the D-channel. CO-binding, NADH and ubiquinol oxidase, and Na + -pumping activities were all substantially inhibited by each mutation. The wild type Vitreoscilla cytochrome bo can pump Na + against a concentration gradient, resulting in a transmembrane concentration differential of 2-3 orders of magnitude. It is proposed that Vitreoscilla cytochrome bo pumps four Na + through the D-channel to the exterior and transports four H + through the K-channel for the reduction of each O 2

  1. Exclusive nuclear location of estrogen receptors in Squalus testis.

    Science.gov (United States)

    Callard, G V; Mak, P

    1985-01-01

    An estrogen (E)-binding molecule having both occupied and unoccupied sites is restricted to nuclear subfractions in the testis of the spiny dogfish (Squalus acanthias). We investigated the hypothesis that a species characterized by high body-fluid osmolarity (1010 mosM) has an estrogen receptor (ER) that binds to chromatin with high affinity and consequently resists redistribution during tissue processing. Although the steroid binding and sedimentation properties of the Squalus nuclear ER conformed to those of classical ER, its elution maximum from DNA-cellulose was unusually high (0.55 M NaCl). A tendency to adhere tightly to cell nuclei was reflected in the high salt concentration (0.43 M KCl) required to extract 50% of the receptors from the nuclear compartment during homogenization and in the stability of the nuclear ER population in the presence of high concentrations of a nonionic solute (urea) or increased buffer volume. Mixing and redistribution experiments showed that nuclear ER could be quantitatively and qualitatively measured in cytosolic extracts, ruling out the possibility that soluble receptors were being masked. Although Squalus oviduct ER was similar to that of testis, ER in the testis and liver of a related elasmobranch (Potamotrygon) that maintains osmotic equilibrium at 300 mosM more closely resembled mammalian ER in its elution maximum from DNA-cellulose (0.22 M NaCl) and cytosolic/nuclear ratios in low-salt buffers. We conclude that Squalus testis has a single ER pool located exclusively in the nuclear compartment. These observations support a revised concept of steroid action and further indicate that the chromatin affinity of the hormone-ER complex is an important factor in determining subfractional distribution during tissue processing. PMID:3856265

  2. Nuclear and Radiochemistry Fundamentals and Applications

    CERN Document Server

    Lieser, Karl Heinrich

    2001-01-01

    This handbook gives a complete and concise description of the up-to-date knowledge of nuclear and radiochemsitry and applications in the various fields of science. I is based on teaching courses and on research for over 40 years. The book is addressed to any researcher whishing sound knowledge about the properties of matter, be it a chemist, a physicist, a medical doctor, a mineralogist or a biologist. They will all find it a valuable source of information about the principles and applications of nuclear and radiochemistry. Research in radiochemistry includes: Study of radioactice matter in na

  3. Longitudinal polarization of positrons in 22Na decay

    International Nuclear Information System (INIS)

    Skalsey, M.; Girard, T.A.; Rich, A.

    1985-01-01

    Detailed descriptions are given of previously reported measurements of the longitudinal polarization (P/sub L/) of positrons in the allowed and unique second forbidden weak decays of 22 Na. The measurements were performed relative to the allowed decay of 68 Ga by application of time-resolved spectroscopy of the n = 1 hyperfine states of positronium formed in powder media. Assuming the theoretical value P/sub L/( 68 Ga) = β(0.999 +- 0.001), the results are P/sub L/( 22 Na, 3 + →2 + ) = β(+1.003 +- 0.011) and P/sub L/( 22 Na, 3 + →0 + ) = β(+1.00 +- 0.05). The allowed decay result (combined with other 22 Na experimental data on the decay rate, the capture ratio, the spectral shape, the βγ directional correlation, and the weak magnetic form factor) yields a determination of the full weak form factor structure of the transition through second order in recoil. The experimental value for the capture ratio is currently considered to be anomalously low compared to theoretical estimates. Our polarization result is not, however, sufficiently accurate to definitively favor one or the other value. The forbidden decay result, together with model-dependent nuclear structure calculations, restricts the contribution of previously neglected higher-order corrections to the allowed decay to be less than 10 -8

  4. Precision mass measurements of very short-lived, neutron-rich Na isotopes using a radiofrequency spectrometer

    CERN Document Server

    Lunney, M D; Doubre, H; Henry, S; Monsanglant, C; De Saint-Simon, M; Thibault, C; Toader, C F; Borcea, C; Bollen, G

    2001-01-01

    Mass measurements of high precision have been performed on sodium isotopes out to $^{30}$Na using a new technique of radiofrequency excitation of ion trajectories in a homogeneous magnetic field. This method, especially suited to very short-lived nuclides, has allowed us to significantly reduce the uncertainty in mass of the most exotic Na isotopes: a relative error of 5x10$^{-7}$ was achieved for $^{28}$Na having a half-life of only 30.5 ms and 9x10$^{-7}$ for the weakly produced $^{30}$Na. Verifying and minimizing binding energy uncertainties in this region of the nuclear chart is important for clarification of a long standing problem concerning the strength of the $N$=20 magic shell closure. These results are the fruit of the commissioning of the new experimental program Mistral.

  5. Paraquat adsorption on NaX and Al-MCM-41.

    Science.gov (United States)

    Rongchapo, Wina; Deekamwong, Krittanun; Loiha, Sirinuch; Prayoonpokarach, Sanchai; Wittayakun, Jatuporn

    2015-01-01

    The aim of this work is to determine paraquat adsorption capacity of zeolite NaX and Al-MCM-41. All adsorbents were synthesized by hydrothermal method using rice husk silica. For Al-MCM-41, aluminum (Al) was added to the synthesis gel of MCM-41 with Al content of 10, 15, 20 and 25 wt%. The faujasite framework type of NaX and mesoporous characteristic of Al-MCM-41 were confirmed by X-ray diffraction. Surface area of all adsorbents determined by N2 adsorption-desorption analysis was higher than 650 m2/g. Al content and geometry were determined by X-ray fluorescence and 27Al nuclear magnetic resonance, respectively. Morphology of Al-MCM-41 were studied by transmission electron microscopy; macropores and defects were observed. The paraquat adsorption experiments were conducted using a concentration range of 80-720 mg/L for NaX and 80-560 mg/L for Al-MCM-41. The paraquat adsorption isotherms from all adsorbents fit well with the Langmuir model. The adsorption capacity of NaX was 120 mg/g-adsorbent. Regarding Al-MCM-41, the 10% Al-MCM-41 exhibited the lowest capacity of 52 mg/g-adsorbent while the other samples had adsorption capacity of 66 mg/g-adsorbent.

  6. Communication of nuclear data progress: No.4(1990)

    International Nuclear Information System (INIS)

    1990-12-01

    Communication of Nuclear Data Progress (CNDP) in English is set up by Chinese Nuclear Committee and Chinese Nuclear Data Center (CNDC). This is the fourth issue. It includes measurements of neutron smaee angle scattering cross sections for Fe, Ni and Cr; n-D scattering phase-shift and 17 O R-matrix analyses; calculations of neutron elastic and inclastic scattering from 7 Li; evaluations of 2 H(n,2n), 23 Na, 59 Co(n, γ), 235,238 U, 239 Pu(n,f) and (n, γ) cross sections; and a fitting code of corrected SLBW with multlievel effect (CBNFIT); R-matrix analysis code (RAC) etc

  7. Regulation of Na(+)/K(+)-ATPase by nuclear respiratory factor 1: implication in the tight coupling of neuronal activity, energy generation, and energy consumption.

    Science.gov (United States)

    Johar, Kaid; Priya, Anusha; Wong-Riley, Margaret T T

    2012-11-23

    NRF-1 regulates mediators of neuronal activity and energy generation. NRF-1 transcriptionally regulates Na(+)/K(+)-ATPase subunits α1 and β1. NRF-1 functionally regulates mediators of energy consumption in neurons. NRF-1 mediates the tight coupling of neuronal activity, energy generation, and energy consumption at the molecular level. Energy generation and energy consumption are tightly coupled to neuronal activity at the cellular level. Na(+)/K(+)-ATPase, a major energy-consuming enzyme, is well expressed in neurons rich in cytochrome c oxidase, an important enzyme of the energy-generating machinery, and glutamatergic receptors that are mediators of neuronal activity. The present study sought to test our hypothesis that the coupling extends to the molecular level, whereby Na(+)/K(+)-ATPase subunits are regulated by the same transcription factor, nuclear respiratory factor 1 (NRF-1), found recently by our laboratory to regulate all cytochrome c oxidase subunit genes and some NMDA and AMPA receptor subunit genes. By means of multiple approaches, including in silico analysis, electrophoretic mobility shift and supershift assays, in vivo chromatin immunoprecipitation, promoter mutational analysis, and real-time quantitative PCR, NRF-1 was found to functionally bind to the promoters of Atp1a1 and Atp1b1 genes but not of the Atp1a3 gene in neurons. The transcripts of Atp1a1 and Atp1b1 subunit genes were up-regulated by KCl and down-regulated by tetrodotoxin. Atp1b1 is positively regulated by NRF-1, and silencing of NRF-1 with small interference RNA blocked the up-regulation of Atp1b1 induced by KCl, whereas overexpression of NRF-1 rescued these transcripts from being suppressed by tetrodotoxin. On the other hand, Atp1a1 is negatively regulated by NRF-1. The binding sites of NRF-1 on Atp1a1 and Atp1b1 are conserved among mice, rats, and humans. Thus, NRF-1 regulates key Na(+)/K(+)-ATPase subunits and plays an important role in mediating the tight coupling between

  8. Eriyik Tuz Reaktörlerinde Yakıt Malzemesi Olarak Kullanılan Na Çekirdeğinin Üretim Tesir Kesiti Hesaplamaları

    Directory of Open Access Journals (Sweden)

    S. Sedat DOĞAN

    2014-12-01

    Full Text Available Özet: Bu çalışmada, eriyik tuz reaktörlerinde yakıt malzemesi olarak kullanılan Na çekirdeğinin üretim tesir kesitleri hesaplanmıştır. Hesaplamalar; 24Mg(p,α21Na, 23Na(n,γ24Na, 24Mg(n,p24Na, 20Ne(d,n21Na ve 23Na(n,2n22Na reaksiyonları için 70 MeV parçacık gelme enerjisine kadar denge ve denge–öncesi nükleer reaksiyon modelleri kullanılarak gerçekleştirilmiştir. Denge–öncesi hesaplamalar için; Full Exciton Model, Hibrit Model, Geometri Bağımlı Hibrit Model ve Cascade Exciton Model, denge hesaplamaları için ise; Weisskopf–Ewing Model kullanılmıştır. Elde edilen sonuçlar, Deneysel Nükleer Reaksiyon Data (EXFOR Kütüphanesi'nden alınan deneysel değerlerle karşılaştırılmıştır. Ayrıca; 21,22,24Na üretimi için optimum enerji aralıkları belirlenmiştir. Anahtar kelimeler: Eriyik tuz reaktörleri, reaksiyon tesir kesiti, EXFOR, denge ve denge–öncesi reaksiyonlar, nükleer reaksiyonlar modelleri Production Cross Section Calculations of Na Nucleus Used as Fuel Material in Molten Salt Reactors Abstract: In this study, the production cross sections of Na nucleus used as fuel material in molten salt reactors have been calculated. The calculations for 24Mg(p,α21Na, 23Na(n,γ24Na, 24Mg(n,p24Na, 20Ne(d,n21Na and 23Na(n,2n22Na reactions have been carried out up to 70 MeV incident particle energies by using the equilibrium and pre–equilibrium nuclear reaction models. Full Exciton Model, Hybrid Model, Geometry Dependent Hybrid Model and Cascade Exciton Model for the pre–equilibrium reactions and Weisskopf–Ewing Model for the equilibrium reactions have been used. The calculated results have been compared with experimental data taken from the Experimental Nuclear Reaction Data (EXFOR library. Also, the optimum energy ranges for 21,22,24Na production have been determined. Key words: Molten salt reactor, reaction cross section, EXFOR, equilibrium and pre–equilibrium reactions, nuclear

  9. Crosslinked Spondia purpurea gum: NaCl and p H effects on the gel absorption capability

    International Nuclear Information System (INIS)

    Silva Junior, Joao Batista A.; Feitosa, Judith P.A.; Paula, Regina C.M.; Paula, Haroldo C.B.

    1999-01-01

    Exudate gum from Spondia purpurea tree was cross linked with epichlorohydrin and its swelling behaviour as a function of Na Cl concentration and pH was investigated. Preliminary structural study was carried out by C-13 nuclear magnetic resonance spectroscopy. The gum was found to absorb 35 time its own weight in water. Swelling increased with pH, being maximal in the pH range 8-10. The equilibrium water content was found to decrease with increasing Na Cl concentration. (author)

  10. Estimation of covariances of {sup 16}O, {sup 23}Na, Fe, {sup 235}U, {sup 238}U and {sup 239}Pu neutron nuclear data in JENDL-3.2

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Keiichi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Nakajima, Yutaka; Kawano, Toshihiko; Oh, Soo-Youl; Matsunobu, Hiroyuki; Murata, Toru

    1997-10-01

    Covariances of nuclear data have been estimated for 6 nuclides contained in JENDL-3.2. The nuclides considered are {sup 16}O, {sup 23}Na, Fe, {sup 235}U, {sup 238}U, and {sup 239}Pu, which are regarded as important for the nuclear design study of fast reactors. The physical quantities for which covariances are deduced are cross sections, resolved and unresolved resonance parameters, and the first order Legendre-polynomial coefficient for the angular distribution of elastically scattered neutrons. As for {sup 235}U, covariances were obtained also for the average number of neutrons emitted in fission. The covariances were estimated by using the same methodology that had been used in the JENDL-3.2 evaluation in order to keep a consistency between mean values and their covariances. The least-squares fitting code GMA was used in estimating covariances for reactions of which JENDL-3.2 cross sections had been evaluated by taking account of measurements. In nuclear model calculations, the covariances were calculated by the KALMAN system. The covariance data obtained were compiled in the ENDF-6 format, and will be put into the JENDL-3.2 Covariance File which is one of JENDL special purpose files. (author). 193 refs.

  11. Na+-stimulated ATPase of alkaliphilic halotolerant cyanobacterium Aphanothece halophytica translocates Na+ into proteoliposomes via Na+ uniport mechanism

    Directory of Open Access Journals (Sweden)

    Soontharapirakkul Kanteera

    2010-08-01

    Full Text Available Abstract Background When cells are exposed to high salinity conditions, they develop a mechanism to extrude excess Na+ from cells to maintain the cytoplasmic Na+ concentration. Until now, the ATPase involved in Na+ transport in cyanobacteria has not been characterized. Here, the characterization of ATPase and its role in Na+ transport of alkaliphilic halotolerant Aphanothece halophytica were investigated to understand the survival mechanism of A. halophytica under high salinity conditions. Results The purified enzyme catalyzed the hydrolysis of ATP in the presence of Na+ but not K+, Li+ and Ca2+. The apparent Km values for Na+ and ATP were 2.0 and 1.2 mM, respectively. The enzyme is likely the F1F0-ATPase based on the usual subunit pattern and the protection against N,N'-dicyclohexylcarbodiimide inhibition of ATPase activity by Na+ in a pH-dependent manner. Proteoliposomes reconstituted with the purified enzyme could take up Na+ upon the addition of ATP. The apparent Km values for this uptake were 3.3 and 0.5 mM for Na+ and ATP, respectively. The mechanism of Na+ transport mediated by Na+-stimulated ATPase in A. halophytica was revealed. Using acridine orange as a probe, alkalization of the lumen of proteoliposomes reconstituted with Na+-stimulated ATPase was observed upon the addition of ATP with Na+ but not with K+, Li+ and Ca2+. The Na+- and ATP-dependent alkalization of the proteoliposome lumen was stimulated by carbonyl cyanide m - chlorophenylhydrazone (CCCP but was inhibited by a permeant anion nitrate. The proteoliposomes showed both ATPase activity and ATP-dependent Na+ uptake activity. The uptake of Na+ was enhanced by CCCP and nitrate. On the other hand, both CCCP and nitrate were shown to dissipate the preformed electric potential generated by Na+-stimulated ATPase of the proteoliposomes. Conclusion The data demonstrate that Na+-stimulated ATPase from A. halophytica, a likely member of F-type ATPase, functions as an electrogenic Na

  12. Spectroscopy of Na-18: Bridging the two-proton radioactivity of Mg-19

    Czech Academy of Sciences Publication Activity Database

    Assie, M.; de Oliveira Santos, F.; Achouri, L.; Angelique, J. C.; Borcea, C.; Borcea, R.; Caceres, L.; Chudoba, V.; Pang, D. Y.; Ducoin, D.; Fallot, M.; Kamalou, O.; Kiener, J.; Lam, Y.; Lefevre, A.; Lotay, G.; Mrázek, Jaromír; Perrot, L.; Sánchez, A.; Rotaru, F.

    2012-01-01

    Roč. 712, č. 3 (2012), s. 198-202 ISSN 0370-2693 Grant - others:European Commission(XE) RII3-CT-2004-506065 Institutional support: RVO:61389005 Keywords : two-proton radioactivity * resonant elastic scattering * (19)mg * Na-18 * Ne-17 Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 4.569, year: 2012

  13. Polarization dependence of Na* + Na* associative ionization revisited

    NARCIS (Netherlands)

    Meijer, H.A.J.; Meulen, H.P. v.d.; Morgenstern, R.; Hertel, I.V.; Meyer, E.; Witte, R.

    1986-01-01

    The dependence of the associative ionization process Na 3 2P3/2 + Na 3 2P3/2 → Na2+ + e- on the polarization of the laser light used for Na excitation was independently investigated in Utrecht and Berlin. The purpose of this paper is to clarify discrepancies between two other earlier experimental

  14. Recent advances in nuclear cardiology

    International Nuclear Information System (INIS)

    Lee, Won Woo

    2016-01-01

    Nuclear cardiology is one of the major fields of nuclear medicine practice. Myocardial perfusion studies using single-photon emission computed tomography (SPECT) have played a crucial role in the management of coronary artery diseases. Positron emission tomography (PET) has also been considered an important tool for the assessment of myocardial viability and perfusion. However, the recent development of computed tomography (CT)/magnetic resonance imaging (MRI) technologies and growing concerns about the radiation exposure of patients remain serious challenges for nuclear cardiology. In response to these challenges, remarkable achievements and improvements are currently in progress in the field of myocardial perfusion imaging regarding the applicable software and hardware. Additionally, myocardial perfusion positron emission tomography (PET) is receiving increasing attention owing to its unique capability of absolute myocardial blood flow estimation. An F-18-labeled perfusion agent for PET is under clinical trial with promising interim results. The applications of F-18 fluorodeoxyglucose (FDG) and F-18 sodium fluoride (NaF) to cardiovascular diseases have revealed details on the basic pathophysiology of ischemic heart diseases. PET/MRI seems to be particularly promising for nuclear cardiology in the future. Restrictive diseases, such as cardiac sarcoidosis and amyloidosis, are effectively evaluated using a variety of nuclear imaging tools. Considering these advances, the current challenges of nuclear cardiology will become opportunities if more collaborative efforts are devoted to this exciting field of nuclear medicine

  15. High-precision half-life determination for 21Na using a 4 π gas-proportional counter

    Science.gov (United States)

    Finlay, P.; Laffoley, A. T.; Ball, G. C.; Bender, P. C.; Dunlop, M. R.; Dunlop, R.; Hackman, G.; Leslie, J. R.; MacLean, A. D.; Miller, D.; Moukaddam, M.; Olaizola, B.; Severijns, N.; Smith, J. K.; Southall, D.; Svensson, C. E.

    2017-08-01

    A high-precision half-life measurement for the superallowed β+ transition between the isospin T =1 /2 mirror nuclei 21Na and 21Ne has been performed at the TRIUMF-ISAC radioactive ion beam facility yielding T1 /2=22.4506 (33 ) s, a result that is a factor of 4 more precise than the previous world-average half-life for 21Na and represents the single most precisely determined half-life for a transition between mirror nuclei to date. The contribution to the uncertainty in the 21Na F tmirror value due to the half-life is now reduced to the level of the nuclear-structure-dependent theoretical corrections, leaving the branching ratio as the dominant experimental uncertainty.

  16. The INS nuclear microprobe and its application

    International Nuclear Information System (INIS)

    Coote, G.E.

    1986-01-01

    The nuclear microprobe directs a well-focused beam of high-energy protons or deuterons at a solid specimen inside a vacuum chamber. Atomic and nuclear reactions are induced in those elements in a layer about 20 micro m thick, leading to the emission of characteristic x-rays, gamma rays, and charged particles as well as Rutherford scattering of the incident beam. These radiations impinge on several detectors near the specimen (NaI, Ge(Li), Si(Li) and Si surface barrier). Using proton-excited x-rays all elements above Na may be detected with sensitivities 10 or 100 times that of the electron probe, while elements which can be estimated from their gamma rays include C, N, O, F, Na and Al. In most of our projects the distribution of a trace or minor element (e.g. F, N) is compared to that of a major element (e.g. Ca or Fe). Recent areas of application include archaeometry (diffusion profiles of F in bones and teeth; depth profiles of sodium in obsidian), geology (F concentrations in mineral grains; studies of the Cretaceous-Tertiary boundary), metallurgy (C, O, N in steel and in welds; S, O, C in corrosion layers), fisheries management (Zn, Sr in otoliths; F in dogfish fin spines and vertebrae), biology (Fe, Sr, N in egg shells; trace elements in human hair), and dental research

  17. CIRFT Data Update and Data Analyses for Spent Nuclear Fuel Vibration Reliability Study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2018-01-01

    The objective of this research is to collect experimental data on spent nuclear fuel (SNF) from pressurized water reactors (PWRs), including the H. B. Robinson Nuclear Power Station (HBR), Catawba Nuclear Station, North Anna Nuclear Power Station (NA), and the Limerick Nuclear Power Station (LMK) boiling water reactor (BWR). Data will be collected under simulated transportation environments using the cyclic integrated reversible-bending fatigue tester (CIRFT), an enabling hot-cell testing technology developed at Oak Ridge National Laboratory (ORNL). These data will be used to support ongoing SNF modeling activities and to address regulatory issues associated with SNF transport.

  18. Nuclear Structure Research at TRIUMF

    Science.gov (United States)

    Garrett, P. E.; Andreyev, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Becker, J. A.; Boston, A. J.; Chakrawarthy, R. S.; Cline, D.; Cooper, R. J.; Churchman, R.; Cross, D.; Dashdorj, D.; Demand, G. A.; Dimmock, M. R.; Drake, T. E.; Finlay, P.; Gagon-Miosan, F.; Gallant, A. T.; Green, K. L.; Grint, A. N.; Grinyer, G. F.; Hackman, G.; Harkness, L. J.; Hayes, A. B.; Kanungo, R.; Kulp, W. D.; Leach, K. G.; Lee, G.; Leslie, J. R.; Martin, J.-P.; Mattoon, C.; Mills, W. J.; Morton, A. C.; Mythili, S.; Nelson, L.; Newman, O.; Nolan, P. J.; Padilla-Rodal, E.; Pearson, C. J.; Phillips, A. A.; Porter-Peden, M.; Ressler, J. J.; Roy, R.; Ruiz, C.; Savajols, H.; Sarazin, F.; Schumaker, M. A.; Scraggs, D. P.; Scraggs, H. C.; Strange, M. D.; Svensson, C. E.; Waddington, J. C.; Wan, J. M.; Whitbeck, A.; Williams, S. J.; Wong, J.; Wood, J. L.; Wu, C. Y.; Zganjar, E. F.

    2007-04-01

    The radioactive beam laboratory at TRIUMF is currently the highest power ISOL facility in the world. Taking advantage of the high-intensity beams, major programs in nuclear astrophysics, nuclear structure, and weak interaction studies have begun. The low-energy area, ISAC-I, is capable of delivering beams up to mass 30 at approx 1.7 MeV/u or 60 keV up to the mass of the primary target, whereas ISAC-II will ultimately provide beams up to mass 150 and approx 6.5 MeV/u. Major gamma -ray spectrometers for nuclear structure research consist of the 8pi spectrometer at ISAC-I, and the TIGRESS spectrometer now being constructed for ISAC-II. Results from recent experiments investigating the beta -decay of nuclei near N=90 and Coulomb excitation of 20,21Na are presented that highlight the capabilities of the spectrometers.

  19. Characterization of polymer-type ionic conductors using nuclear magnetic resonance and thermal analysis. Humidity sensor; Caracterizacao de condutores ionicos de tipo polimerico por ressonancia magnetica nuclear (RMN) e analises termicas. Sensor de umidade

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcante, Maria Goretti

    1992-04-01

    We report a study using Nuclear Magnetic Resonance (NMR), Thermogravimetry Analysis, Differential Scanning Calorimetry and Infrared Spectroscopy in polymeric complexes formed poly(ethylene oxide), (PEO), and lithium salts. These complexes have have shown a large potential for technological applications in batteries, sensors, etc. We developed and characterized humidity sensors and discussed how the humidity affects the conformation of the complexes, the mobility of ionic species, and the polymeric chains. The results indicate that the hydration affects the conformation of polymeric complexes by plasticizing the water, which induces a volumetric expansion in the PEO chain. The processes was completely reversible for the level of hydration studied. NMR was used to distinguish the movement of polymeric chains from the movement of the ionic species. From the analysis of the second moment of resonance lines from the study of the nuclear relaxation we were able to estimate the average distance between the ionic species and the proton in the complexes chains. The behaviour of spin -lattice relaxation of hydrogen and fluorine in the P(EO) - Li B F, as a function of temperature and frequency reflects the nature of the disorder and the complexity of the ionic conduction process in these materials. (author). 91 refs., 69 figs., 2 tabs.

  20. Radiological respiratory protection in Angra-1 Nuclear Power Plant; Protecao respiratoria radiologica na Usina Nuclear de Angra

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Marcos A. do [Furnas Centrais Eletricas S.A., Angra dos Reis, RJ (Brazil). Central Nuclear de Angra I. Div. de Protecao Radiologica e Ambiental

    1996-07-01

    The present paper has the purpose to describe the actual situation of the Radiological respiratory Protection in Angra I Nuclear Power Plant, the difficulties found and the goals to achieve, in order of the radiological protection excellence. (author)

  1. ON01210.Na (Ex-RAD® mitigates radiation damage through activation of the AKT pathway.

    Directory of Open Access Journals (Sweden)

    Anthony D Kang

    Full Text Available Development of radio-protective agents that are non-toxic is critical in light of ever increasing threats associated with proliferation of nuclear materials, terrorism and occupational risks associated with medical and space exploration. In this communication, we describe the discovery, characterization and mechanism of action of ON01210.Na, which effectively protects mouse and human bone marrow cells from radiation-induced damage both in vitro and in vivo. Our results show that treatment of normal fibroblasts with ON01210.Na before and after exposure to ionizing radiation provides dose dependent protection against radiation-induced damage. Treatment of mice with ON01210.Na prior to radiation exposure was found to result in a more rapid recovery of their hematopoietic system. The mechanistic studies described here show that ON01210.Na manifests its protective effects through the up-regulation of PI3-Kinase/AKT pathways in cells exposed to radiation. These results suggest that ON 01210.Na is a safe and effective radioprotectant and could be a novel agent for use in radiobiological disasters.

  2. Pseudo-ternary phase diagram in the Na2O-Na2O2-NaOH system

    International Nuclear Information System (INIS)

    Saito, Jun-ichi; Tendo, Masayuki; Aoto, Kazumi

    1997-10-01

    Generally, the phase diagrams are always used to understand the present state of compounds at certain temperature. In order to understand the corrosion behavior of structural material for FBR by main sodium compounds (Na 2 O, Na 2 O 2 and NaOH), it is very important to comprehend the phase diagrams of their compounds. However, only Na 2 O-NaOH pseudo-binary phase diagram had been investigated previously in this system. There is no study of other pseudo-binary or ternary phase diagrams in the Na 2 O-Na 2 O 2 -NaOH system. In this study, in order to clarify the present states of their compounds at certain temperatures, the pseudo-binary and ternary phase diagrams in the Na 2 O-Na 2 O 2 -NaOH system were prepared. A series of thermal analyses with binary and ternary component system has been carried out using the differential scanning calorimetry (DSC). The liquidus temperature and ternary eutectic temperatures were confirmed by these measurements. The beneficial indications for constructing phase diagrams were obtained from these experiments. On the basis of these results, the interaction parameters between compounds which were utilized for the Thermo-Calc calculation were optimized. Thermo-Calc is one of thermodynamic calculation software. Consequently the accurate pseudo-binary and ternary phase diagrams were indicated using the optimized parameters. (author)

  3. ReNuAL: Renovation of the Nuclear Applications Laboratories

    International Nuclear Information System (INIS)

    Harman, Ruzanna

    2014-01-01

    The IAEA Department of Nuclear Sciences and Applications (NA) operates eight laboratories in Seibersdorf, near Vienna. Each of these laboratories performs unique functions that include supporting research and training for improving animal production and health, ensuring the effective and safe use of radiotherapy equipment, reinforcing food safety and developing hardier and higher-yielding food crops. They also contribute to protecting the global environment, enhancing countries’ capabilities in using nuclear instrumentation and analytical techniques, eliminating insect pests and managing soil and water sustainably. These are essential contributions to the IAEA’s mission of supporting the peaceful use of nuclear technologies to help meet global development challenges

  4. LOCALIZATION OF Na+, K+-ATPASE AND OTHER ENZYMES IN TELEOST PSEUDOBRANCH

    Science.gov (United States)

    Dendy, Leslie A.; Deter, Russell L.; Philpott, Charles W.

    1973-01-01

    In an effort to determine the subcellular localization of sodium- and potassium-activated adenosine triphosphatase (Na+, K+-ATPase) in the pseudobranch of the pinfish Lagodon rhomboides, this tissue was fractionated by differential centrifugation and the activities of several marker enzymes in the fractions were measured. Cytochrome c oxidase was found primarily in the mitochondrial-light mitochondrial (M+L) fraction. Phosphoglucomutase appeared almost exclusively in the soluble (S) fraction. Monoamine oxidase was concentrated in the nuclear (N) fraction, with a significant amount also in the microsomal (P) fraction but little in M+L or S. Na+, K+-ATPase and ouabain insensitive Mg2+-ATPase were distributed in N, M+L, and P, the former having its highest specific activity in P and the latter in M+L. Rate sedimentation analysis of the M+L fraction indicated that cytochrome c oxidase and Mg2+-ATPase were associated with a rapidly sedimenting particle population (presumably mitochondria), while Na+, K+-ATPase was found primarily in a slowly sedimenting component. At least 75% of the Na+, K+-ATPase in M+L appeared to be associated with structures containing no Mg2+-ATPase. Kinetic properties of the two ATPases were studied in the P fraction and were typical of these enzymes in other tissues. Na+, K+-ATPase activity was highly dependent on the ratio of Na+ and K+ concentrations but independent of absolute concentrations over at least a fourfold range. PMID:4349221

  5. Átomos na integração: a aproximação Brasil-Argentina no campo nuclear e a construção do Mercosul

    Directory of Open Access Journals (Sweden)

    Everton Vieira Vargas

    1997-06-01

    Full Text Available Este trabalho tenciona ser uma reflexão sobre a importância da aproximação entre o Brasil e a Argentina no campo nuclear, na segunda metade da década de 80 e no início dos anos 90, como fundamento para a construção de um relacionamento novo que suplantou uma rivalidade histórica entre ambos. O processo de aproximação encetado com um propósito aparentemente econômico, tinha uma dimensão estratégica. As repercussões desse esforço iam além dos interesses bilaterais imediatos e se refletiram na busca de uma nova inserção internacional dos dois países, num momento de transformações profundas nos planos interno e internacional. Através do programa de integração Brasil-Argentina (que mais tarde também envolveu o Uruguai e do MERCOSUL buscou-se estabelecer uma arquitetura político-jurídica, que criou uma realidade que extrapola o campo econômico e projeta-se no terreno político.This paper aims to be a reflection on the importance of the Brazil and Argentina closer relations in the nuclear field, in the late eighties and early nineties, as the basis for building a new relationship that replaced a historical rivalry. The aproximation process has begun with apparently economic purposes, but also had a strategic dimension. The repercussions of this effort went beyond immediate bilateral interests, reflected in the search for a new international insertion by both countries, at a time of deep transformations, both internally and internationally. The Brazil-Argentina integration program (that later also involved Uruguay and MERCOSUL led to the establishment of a political-legal structure that created a reality that goes beyond economics to the political domain.

  6. Extracellular Na+ levels regulate formation and activity of the NaX/alpha1-Na+/K+-ATPase complex in neuronal cells.

    Directory of Open Access Journals (Sweden)

    Emmanuelle eBerret

    2014-12-01

    Full Text Available MnPO neurons play a critical role in hydromineral homeostasis regulation by acting as sensors of extracellular sodium concentration ([Na+]out. The mechanism underlying Na+-sensing involves Na+-flow through the NaX channel, directly regulated by the Na+/K+-ATPase α1-isoform which controls Na+-influx by modulating channel permeability. Together, these two partners form a complex involved in the regulation of intracellular sodium ([Na+]in. Here we aim to determine whether environmental changes in Na+ could actively modulate the NaX/Na+/K+-ATPase complex activity.We investigated the complex activity using patch-clamp recordings from rat MnPO neurons and Neuro2a cells. When the rats were fed with a high-salt-diet, or the [Na+] in the culture medium was increased, the activity of the complex was up-regulated. In contrast, drop in environmental [Na+] decreased the activity of the complex. Interestingly under hypernatremic condition, the colocalization rate and protein level of both partners were up-regulated. Under hyponatremic condition, only NaX protein expression was increased and the level of NaX/Na+/K+-ATPase remained unaltered. This unbalance between NaX and Na+/K+-ATPase pump proportion would induce a bigger portion of Na+/K+-ATPase-control-free NaX channel. Thus we suggest that hypernatremic environment increases NaX/Na+/K+-ATPase α1-isoform activity by increasing the number of both partners and their colocalization rate, whereas hyponatremic environment down-regulates complex activity via a decrease in the relative number of NaX channels controlled by the pump.

  7. Development and study of airborne spectrometer system being compatible with nuclear emergency monitoring

    International Nuclear Information System (INIS)

    Jiangqi, Fang; Huaiwu, Wang; Mingkao, Hu; Renkang, Gu

    2002-01-01

    The exploitation and use of nuclear energy are of great importance to developing of national economy and maintaining state security. But it also has a possibility of serious accident. Based on the principles of airborne gamma ray spectrometry in the uranium exploration, nuclear emergency monitoring has been developed. This method has high sensitivity to the radioactive nuclides in the air and on the ground, and with the advantage of fast measuring in large area. Hence, in the middle of 1980s, some developed countries began to survey the scope and degree of nuclear accident contamination and environmental radiation level monitoring in the surrounding nuclear facilities, it can also be used to search for the lost radioactive sources. According to the actual situation and compatible guideline, National Nuclear Emergency Office consigned this project to our Center. After development and study on the Airborne gamma ray spectrometer system associated NaI(Tl) used for the uranium exploration, a compatible spectrometer system associated NaI(Tl) was established in a short period by us, which can fulfill airborne nuclear emergency survey basically. In normal situation, it was proved that the start-up time is less than two hours including transport to the airport. The system has high sensitivity to radioactive plume of 41 Ar and can respond rapidly to artificial sources, such as 192 Ir, 60 Co, 137 Cs and 131 I etc

  8. Família e o processo de diferenciação na perspectiva de Murray Bowen: um estudo de caso

    Directory of Open Access Journals (Sweden)

    Elizabeth Medeiros de Almeida Martins

    2008-06-01

    Full Text Available Este estudo teve como objetivo investigar a aplicabilidade do conceito de diferenciação do self elaborado por Murray Bowen na terapia da família. Focalizou a história de uma família mostrando como as histórias de vida do casal, a partir das primeiras triangulações, tanto na família nuclear quanto na extensa, foram transmitidas entre gerações até gerar uma história renovada do casal e de sua própria família.

  9. A Study of the Distribution of Sodium Cations in the Zeolites NaX, NaY and ZnNaY Using Carbon Monoxide Adsorption and 23Na NMR Techniques

    Science.gov (United States)

    Seidel, A.; Boddenberg, B.

    1995-03-01

    The zeolites NaX, NaY, Zn(55)NaY, and Zn(74)NaY were investigated by means of carbon monoxide adsorption and with static and magic angle spinning (MAS) 23Na NMR spectroscopy. The Na+ distribution between the sodalite (ß)- and supercages of the fully hydrated zeolites NaX and NaY were found to agree with XRD results. In the hydrated zinc-exchanged zeolites the Na+ ions almost exclusively populate the ß-cages. The adsorption isotherms of CO in the dehydrated zeolites were analyzed quantitatively to yield the concentrations of Na+ residing in the supercages. The measured static and MAS 23Na NMR spectra were analyzed by comparing their widths and shapes with simulated central transition patterns and yield, inter alia, the concentrations of Na+ associated with the spectrum components. Arguments are put forward that 23Na NMR of dehydrated zeolites is well suited to distinguish Na+ cations in highly symmetric environments and mobile Na+ species from others located on general positions, but further resolution is hardly feasible.

  10. HCO3(-)-coupled Na+ influx is a major determinant of Na+ turnover and Na+/K+ pump activity in rat hepatocytes

    International Nuclear Information System (INIS)

    Fitz, J.G.; Lidofsky, S.D.; Weisiger, R.A.; Xie, M.H.; Cochran, M.; Grotmol, T.; Scharschmidt, B.F.

    1991-01-01

    Recent studies in hepatocytes indicate that Na(+)-coupled HCO3- transport contributes importantly to regulation of intracellular pH and membrane HCO3- transport. However, the direction of net coupled Na+ and HCO3- movement and the effect of HCO3- on Na+ turnover and Na+/K+ pump activity are not known. In these studies, the effect of HCO3- on Na+ influx and turnover were measured in primary rat hepatocyte cultures with 22Na+, and [Na+]i was measured in single hepatocytes using the Na(+)-sensitive fluorochrome SBFI. Na+/K+ pump activity was measured in intact perfused rat liver and hepatocyte monolayers as Na(+)-dependent or ouabain-suppressible 86Rb uptake, and was measured in single hepatocytes as the effect of transient pump inhibition by removal of extracellular K+ on membrane potential difference (PD) and [Na+]i. In hepatocyte monolayers, HCO3- increased 22Na+ entry and turnover rates by 50-65%, without measurably altering 22Na+ pool size or cell volume, and HCO3- also increased Na+/K+ pump activity by 70%. In single cells, exposure to HCO3- produced an abrupt and sustained rise in [Na+]i from approximately 8 to 12 mM. Na+/K+ pump activity assessed in single cells by PD excursions during transient K+ removal increased congruent to 2.5-fold in the presence of HCO3-, and the rise in [Na+]i produced by inhibition of the Na+/K+ pump was similarly increased congruent to 2.5-fold in the presence of HCO3-. In intact perfused rat liver, HCO3- increased both Na+/K+ pump activity and O2 consumption. These findings indicate that, in hepatocytes, net coupled Na+ and HCO3- movement is inward and represents a major determinant of Na+ influx and Na+/K+ pump activity. About half of hepatic Na+/K+ pump activity appears dedicated to recycling Na+ entering in conjunction with HCO3- to maintain [Na+]i within the physiologic range

  11. Electronic structure of fractionally nuclear charged atoms

    International Nuclear Information System (INIS)

    Pavao, Antonio C.; Bastos, Cristiano C.; Ferreira, Joacy V.

    2008-01-01

    Different properties of quark chemistry are studied by performing accurate ab initio Hartree- Fock calculations on fractionally nuclear charged atoms. Ground and first excited states of sodium atoms with quarks attached to the nucleus are obtained using CI calculations. It is suggested that the sodium 2 P -> 2 S electronic transition can be used as a guide in searching for unconfined quarks. Also, the variation of the binding electronic energy with nuclear charge in the isoelectronic series of fractionally nuclear charged atoms A ±2/3 and A ±1/3 (A = H, Li, Na, P and Ca) is analyzed. The present calculations suggest that unconfined colored particles have large appetite for heavy nuclei and that quark-antiquark pairs could be stabilized in presence of the atomic matter. (author)

  12. The effect of Na vapor on the Na content of chondrules

    Science.gov (United States)

    Lewis, R. Dean; Lofgren, Gary E.; Franzen, Hugo F.; Windom, Kenneth E.

    1993-01-01

    Chondrules contain higher concentrations of volatiles (Na) than expected for melt droplets in the solar nebula. Recent studies have proposed that chondrules may have formed under non-canonical nebular conditions such as in particle/gas-rich clumps. Such chondrule formation areas may have contained significant Na vapor. To test the hypothesis of whether a Na-rich vapor would minimize Na volatilization reaction rates in a chondrule analog and maintain the Na value of the melt, experiments were designed where a Na-rich vapor could be maintained around the sample. A starting material with a melting point lower that typical chondrules was required to keep the logistics of working with Na volatilization from NaCl within the realm of feasibility. The Knippa basalt, a MgO-rich alkali olivine basalt with a melting temperature of 1325 +/- 5 C and a Na2O content of 3.05 wt%, was used as the chondrule analog. Experiments were conducted in a 1 atm, gas-mixing furnace with the fO2 controlled by a CO/CO2 gas mixture and fixed at the I-W buffer curve. To determine the extent of Na loss from the sample, initial experiments were conducted at high temperatures (1300 C - 1350 C) for duration of up to 72 h without a Na-rich vapor present. Almost all (up to 98%) Na was volatilized in runs of 72 h. Subsequent trials were conducted at 1330 C for 16 h in the presence of a Na-rich vapor, supplied by a NaCl-filled crucible placed in the bottom of the furnace. Succeeding Knudsen cell weight-loss mass-spectrometry analysis of NaCl determined the P(sub Na) for these experimental conditions to be in the 10(exp -6) atm range. This value is considered high for nebula conditions but is still plausible for non-canonical environments. In these trials the Na2O content of the glass was maintained or in some cases increased; Na2O values ranged from 2.62% wt to 4.37% wt. The Na content of chondrules may be controlled by the Na vapor pressure in the chondrule formation region. Most heating events capable

  13. The NA60 experiment results and perspectives

    CERN Document Server

    Heuser, J M; Banicz, K; Borer, K; Buytaert, J; Castor, J I; Chaurand, B; Chenn, W; Cheynis, B; Cicalò, C; Colla, A; Cortese, R; David, A; De Falco, A; De Marco, N; Devaux, A; Drees, A; Ducroux, L; Enyo, H; Ferretti, A; Floris, M; Force, P; Grigorian, A A; Grossiord, J Y; Guettet, N; Guichard, A; Gulkanian, H R; Keil, M; Kluberg, L; Li, Z; Lourenço, C; Lozano-Bahilo, J; Manso, F; Masoni, A; Neves, A; Ohnishi, H; Oppedisano, C; Parracho, P; Puddu, G; Radermacher, E; Rosinsky, P; Scomparin, E; Seixas, J; Serci, S; Shahoyan, R; Sonderegger, P; Tieulent, R; Usai, G L; Vardanian, H; Veenhof, R; Wöhri, H K

    2003-01-01

    The NA60 experiment takes place at the SPS at CERN, to study the production of open charm and prompt dimuons in collisions induced by proton and heavy ion beams on nuclear targets. For this task, several novel detector systems were added to the dimuon spectrometer and zero-degree calorimeter, which were previously used in the NA50 experiment. The main upgrade is a new silicon pixel vertex spectrometer. It tracks the charged particles that are produced through the collisions in the target and allows us to match their trajectories and momenta with those of the muons that are measured behind the hadron absorber in the muon spectrometer. Besides improving considerably the dimuon mass resolution, the vertex telescope measures the offset of each muon track with respect to the interaction point. This allows us to select events where charm mesons were produced. We present in this article first results from dimuon data that were acquired in Summer 2002 with a 400 GeV proton beam. A silicon microstrip telescope was use...

  14. Na/K pump inactivation, subsarcolemmal Na measurements, and cytoplasmic ion turnover kinetics contradict restricted Na spaces in murine cardiac myocytes.

    Science.gov (United States)

    Lu, Fang-Min; Hilgemann, Donald W

    2017-07-03

    Decades ago, it was proposed that Na transport in cardiac myocytes is modulated by large changes in cytoplasmic Na concentration within restricted subsarcolemmal spaces. Here, we probe this hypothesis for Na/K pumps by generating constitutive transsarcolemmal Na flux with the Na channel opener veratridine in whole-cell patch-clamp recordings. Using 25 mM Na in the patch pipette, pump currents decay strongly during continuous activation by extracellular K (τ, ∼2 s). In contradiction to depletion hypotheses, the decay becomes stronger when pump currents are decreased by hyperpolarization. Na channel currents are nearly unchanged by pump activity in these conditions, and conversely, continuous Na currents up to 0.5 nA in magnitude have negligible effects on pump currents. These outcomes are even more pronounced using 50 mM Li as a cytoplasmic Na congener. Thus, the Na/K pump current decay reflects mostly an inactivation mechanism that immobilizes Na/K pump charge movements, not cytoplasmic Na depletion. When channel currents are increased beyond 1 nA, models with unrestricted subsarcolemmal diffusion accurately predict current decay (τ ∼15 s) and reversal potential shifts observed for Na, Li, and K currents through Na channels opened by veratridine, as well as for Na, K, Cs, Li, and Cl currents recorded in nystatin-permeabilized myocytes. Ion concentrations in the pipette tip (i.e., access conductance) track without appreciable delay the current changes caused by sarcolemmal ion flux. Importantly, cytoplasmic mixing volumes, calculated from current decay kinetics, increase and decrease as expected with osmolarity changes (τ >30 s). Na/K pump current run-down over 20 min reflects a failure of pumps to recover from inactivation. Simulations reveal that pump inactivation coupled with Na-activated recovery enhances the rapidity and effectivity of Na homeostasis in cardiac myocytes. In conclusion, an autoregulatory mechanism enhances cardiac Na/K pump activity when

  15. Analysis of oil content in sunflower seeds with nuclear magnetic ressonance and `SOXHLET` methods; Determinacao do teor de oleo em sementes de girassol pelos metodos de ressonancia magnetica nuclear e soxhlet

    Energy Technology Data Exchange (ETDEWEB)

    Ungaro, Maria Regina Goncalves [Instituto Agronomico de Campinas, SP (Brazil). Secao de Oleaginosas; Toledo, Nilva Maria Prestes de [Instituto Agronomico de Campinas, SP (Brazil). Secao Tecnica Experimental e Calculo; Teixeira, Joao Paulo Feijao [Instituto Agronomico de Campinas, SP (Brazil). Secao de Fitoquimica; Suassuna Filho, Jose [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Dept.de Fisica

    1993-12-31

    Individual and group of seeds of some sunflower populations were utilized in order to evaluate the feasibility of oil content evaluations by the Nuclear Magnetic Resonance method (NMR). Correlation analysis with the extractive method (Soxhlet) was performed. The results showed that: the oil in the seeds behaved like a liquid in the NMR analysis; there was a high and positive correlation (r = 0,93) between NMR and Soxhlet; there was no correlation between seed weight and oil content; the observed variability in oil content among seeds of a plant were higher than between plants of a population; these values indicate the importance of making individual analysis of oil content by the NMR method for the sunflower breeding for oil content. (author) 7 refs., 2 figs., 4 tabs.

  16. Explosive hazards analysis of the eutectic solution NaK and KO2

    International Nuclear Information System (INIS)

    Commander, J.C.

    1975-06-01

    Planning, preparation, conductance, and evaluation of field tests are reported to determine the explosive hazards associated with the combining of the sodium-potassium eutectic alloy (NaK) with the superoxide of potassium (KO 2 ) under various conditions of state, contamination, and detonation initiation. The planning and preparation was conducted by Aerojet Nuclear Company (ANC) at the Idaho National Engineering Laboratory, and the explosive hazards testing was done by Cook Associates, Inc., at IRECO Chemicals Pelican Point Research and Development facility in Utah. The test results showed that binary combinations of pure NaK and KO 2 could not be made to detonate, although the mixtures will spontaneously ignite and burn. However, tertiary combinations of NaK, KO 2 plus a water or hydrocarbon contaminant produced explosive hazards under a variety of conditions. The work was performed as part of the Decontamination and Decommissioning (D and D) of the first Experimental Breeder Reactor (EBR-I) and was funded by 189c I-215. (U.S.)

  17. Nuclear Data Parameter Adjustment BNL-INL

    International Nuclear Information System (INIS)

    Palmiotti, G.; Hoblit, S.; Herman, M.; Nobre, G.P.A.; Palumbo, A.; Hiruta, H.; Salvatores, M.

    2013-01-01

    This presentation reports on the consistent adjustment of nuclear data parameters performed within a BNL-INL collaboration. The main advantage compared to the classical adjustment of multigroup constants is to provide final nuclear data constrained by the nuclear reaction theory and consistent with both differential and integral measurements. The feasibility of a single-isotope assimilation was tested on a few priority materials ( 23 Na, 56 Fe, 105 Pd, 235,238 U, 239 Pu) using a selection of clean integral experiments. The multi-isotope assimilation is under study for the Big-3 ( 235,238 U, 239 Pu). This work shows that a consistent assimilation is feasible, but there are pitfalls to avoid (e.g. non-linearity, cross section fluctuations) and prerequisites (e.g. realistic covariances, good prior, realistic weighting of differential and integral experiments). Finally, only all experimental information combined with the state of the art modelling may provide a 'right' answer

  18. Influenza polymerase encoding mRNAs utilize atypical mRNA nuclear export.

    Science.gov (United States)

    Larsen, Sean; Bui, Steven; Perez, Veronica; Mohammad, Adeba; Medina-Ramirez, Hilario; Newcomb, Laura L

    2014-08-28

    Influenza is a segmented negative strand RNA virus. Each RNA segment is encapsulated by influenza nucleoprotein and bound by the viral RNA dependent RNA polymerase (RdRP) to form viral ribonucleoproteins responsible for RNA synthesis in the nucleus of the host cell. Influenza transcription results in spliced mRNAs (M2 and NS2), intron-containing mRNAs (M1 and NS1), and intron-less mRNAs (HA, NA, NP, PB1, PB2, and PA), all of which undergo nuclear export into the cytoplasm for translation. Most cellular mRNA nuclear export is Nxf1-mediated, while select mRNAs utilize Crm1. Here we inhibited Nxf1 and Crm1 nuclear export prior to infection with influenza A/Udorn/307/1972(H3N2) virus and analyzed influenza intron-less mRNAs using cellular fractionation and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). We examined direct interaction between Nxf1 and influenza intron-less mRNAs using immuno purification of Nxf1 and RT-PCR of associated RNA. Inhibition of Nxf1 resulted in less influenza intron-less mRNA export into the cytoplasm for HA and NA influenza mRNAs in both human embryonic kidney cell line (293 T) and human lung adenocarcinoma epithelial cell line (A549). However, in 293 T cells no change was observed for mRNAs encoding the components of the viral ribonucleoproteins; NP, PA, PB1, and PB2, while in A549 cells, only PA, PB1, and PB2 mRNAs, encoding the RdRP, remained unaffected; NP mRNA was reduced in the cytoplasm. In A549 cells NP, NA, HA, mRNAs were found associated with Nxf1 but PA, PB1, and PB2 mRNAs were not. Crm1 inhibition also resulted in no significant difference in PA, PB1, and PB2 mRNA nuclear export. These results further confirm Nxf1-mediated nuclear export is functional during the influenza life cycle and hijacked for select influenza mRNA nuclear export. We reveal a cell type difference for Nxf1-mediated nuclear export of influenza NP mRNA, a reminder that cell type can influence molecular mechanisms. Importantly, we

  19. Spastin-Interacting Protein NA14/SSNA1 Functions in Cytokinesis and Axon Development

    Science.gov (United States)

    Chang, Jaerak; Blackstone, Craig

    2014-01-01

    Hereditary spastic paraplegias (HSPs) are a genetically diverse group of inherited neurological disorders (SPG1-72) with the cardinal feature of prominent lower-extremity spasticity due to a length-dependent axonopathy of corticospinal motor neurons. The most frequent form of autosomal dominant HSP results from mutations of the SPG4 gene product spastin. This is an ATPase associated with diverse cellular activities (AAA) protein that binds to and severs microtubules. While spastin participates in crucial cellular processes such as cytokinesis, endosomal tubulation, and axon development, its role in HSP pathogenesis remains unclear. Spastin interacts in cells with the NA14 protein, a major target for auto-antibodies in Sjögren's syndrome (nuclear autoantigen 1; SSNA1). Our analysis of endogenous spastin and NA14 proteins in HeLa cells and rat cortical neurons in primary culture revealed a clear distribution of both proteins to centrosomes, with NA14 localizing specifically to centrioles. Stable NA14 knockdown in cell lines dramatically affected cell division, in particular cytokinesis. Furthermore, overexpression of NA14 in neurons significantly increased axon outgrowth and branching, while also enhancing neuronal differentiation. We postulate that NA14 may act as an adaptor protein regulating spastin localization to centrosomes, temporally and spatially regulating the microtubule-severing activity of spastin that is particularly critical during the cell cycle and neuronal development. PMID:25390646

  20. Spastin-interacting protein NA14/SSNA1 functions in cytokinesis and axon development.

    Directory of Open Access Journals (Sweden)

    Uma Goyal

    Full Text Available Hereditary spastic paraplegias (HSPs are a genetically diverse group of inherited neurological disorders (SPG1-72 with the cardinal feature of prominent lower-extremity spasticity due to a length-dependent axonopathy of corticospinal motor neurons. The most frequent form of autosomal dominant HSP results from mutations of the SPG4 gene product spastin. This is an ATPase associated with diverse cellular activities (AAA protein that binds to and severs microtubules. While spastin participates in crucial cellular processes such as cytokinesis, endosomal tubulation, and axon development, its role in HSP pathogenesis remains unclear. Spastin interacts in cells with the NA14 protein, a major target for auto-antibodies in Sjögren's syndrome (nuclear autoantigen 1; SSNA1. Our analysis of endogenous spastin and NA14 proteins in HeLa cells and rat cortical neurons in primary culture revealed a clear distribution of both proteins to centrosomes, with NA14 localizing specifically to centrioles. Stable NA14 knockdown in cell lines dramatically affected cell division, in particular cytokinesis. Furthermore, overexpression of NA14 in neurons significantly increased axon outgrowth and branching, while also enhancing neuronal differentiation. We postulate that NA14 may act as an adaptor protein regulating spastin localization to centrosomes, temporally and spatially regulating the microtubule-severing activity of spastin that is particularly critical during the cell cycle and neuronal development.

  1. Composition - structure - properties relationships of peraluminous glasses for nuclear waste containment

    International Nuclear Information System (INIS)

    Piovesan, Victor

    2016-01-01

    Part of the Research and Development program concerning high level nuclear waste conditioning aims to assess new glass formulations able to incorporate a high waste content with enhanced properties in terms of homogeneity, thermal stability, long term behavior and process ability. This study focuses on peraluminous glasses, defined by an excess of aluminum ions Al"3"+ in comparison with modifier elements such as Na"+, Li"+ or Ca"2"+. A Design of Experiment approach has been employed to determine relationships between composition of simplified peraluminous glasses (SiO_2 - B_2O_3 - Al_2O_3 - Na_2O - Li_2O - CaO - La_2O_3) and their physical properties such as viscosity, glass transition temperature and glass homogeneity. Moreover, some structural investigation (NMR) was performed in order to better understand the structural role of Na"+, Li"+ and Ca"2"+ and the structural organization of peraluminous glasses. Then, physical and chemical properties of fully simulated peraluminous glasses were characterized to evaluate transposition between simplified and fully simulated glasses and also to put forward the potential of peraluminous glasses for nuclear waste containment. (author) [fr

  2. Ergonomics in the licensing and evaluation of nuclear reactors control room; A ergonomia no licenciamento e na avaliacao de salas de controle de reatores nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Isaac Jose Antonio Luquetti dos [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil); Vidal, Mario Cesar Rodriguez [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia de Producao

    2002-07-01

    A nuclear control room is a complex system that controls a thermodynamic process used to produce electrical energy. The operators interact with the control room through interfaces that have significant implications to nuclear plant safety and influence the operator activity. The TMI (Three Mile Island) accident demonstrated that only the anthropometric aspects were not enough for an adequate nuclear control room design. The studies showed that the accident was aggravated because the designers had not considered adequately human factor aspects. After TMI accident, the designers introduce in the nuclear control room development only human factors standards and human factors guidelines. The ergonomics approaches was not considered. Our objective is introduce in nuclear control room design and nuclear control room evaluation, a methodology that. includes human factors standards, human factors guidelines and ergonomic approaches, the operator activity analysis. (author)

  3. Na+/Ca2+ exchange and Na+/K+-ATPase in the heart

    Science.gov (United States)

    Shattock, Michael J; Ottolia, Michela; Bers, Donald M; Blaustein, Mordecai P; Boguslavskyi, Andrii; Bossuyt, Julie; Bridge, John H B; Chen-Izu, Ye; Clancy, Colleen E; Edwards, Andrew; Goldhaber, Joshua; Kaplan, Jack; Lingrel, Jerry B; Pavlovic, Davor; Philipson, Kenneth; Sipido, Karin R; Xie, Zi-Jian

    2015-01-01

    This paper is the third in a series of reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation–contraction coupling and arrhythmias: Na+ channel and Na+ transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on cardiac Na+/Ca2+ exchange (NCX) and Na+/K+-ATPase (NKA). While the relevance of Ca2+ homeostasis in cardiac function has been extensively investigated, the role of Na+ regulation in shaping heart function is often overlooked. Small changes in the cytoplasmic Na+ content have multiple effects on the heart by influencing intracellular Ca2+ and pH levels thereby modulating heart contractility. Therefore it is essential for heart cells to maintain Na+ homeostasis. Among the proteins that accomplish this task are the Na+/Ca2+ exchanger (NCX) and the Na+/K+ pump (NKA). By transporting three Na+ ions into the cytoplasm in exchange for one Ca2+ moved out, NCX is one of the main Na+ influx mechanisms in cardiomyocytes. Acting in the opposite direction, NKA moves Na+ ions from the cytoplasm to the extracellular space against their gradient by utilizing the energy released from ATP hydrolysis. A fine balance between these two processes controls the net amount of intracellular Na+ and aberrations in either of these two systems can have a large impact on cardiac contractility. Due to the relevant role of these two proteins in Na+ homeostasis, the emphasis of this review is on recent developments regarding the cardiac Na+/Ca2+ exchanger (NCX1) and Na+/K+ pump and the controversies that still persist in the field. PMID:25772291

  4. Communication of nuclear data progress: No.6 Supplement (1992)

    International Nuclear Information System (INIS)

    1992-10-01

    This is a supplement to No.6 of Communication of Nuclear Data Progress (CNDP), in which the second and final part of the papers of CENDL-2 (Chinese Evaluated Nuclear Data Library, Version 2.0) is published. It includes the evaluation reports of 17 elements and isotopes with incident neutron energy from 10 -5 eV to 20 MeV, they are 16 O, 23 Na, 31 P, Ca, Zn, Mn, 59 Co, Cd, In, Hf, 232 Th, 235 U, 239 Pu, 240 Pu, 241 Am, 249 Bk, 249 Cf

  5. Nuclear magnetic resonance studies in solid polymeric electrolyte. Estudos por ressonancia magnetica nuclear em eletrolitos polimericos solidos

    Energy Technology Data Exchange (ETDEWEB)

    Donoso, J P; Mattoso, L H.C.; Cavalcante, M G [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Fisica e Quimica; Gorecki, W; Berthier, C; Armand, M [Universite J. Fourier, Grenoble (France)

    1990-01-01

    Solid complexes formed between Poly (ethylene oxide) and various alkali metal salts, are generally referred to as polymer electrolytes conductivity and NMR properties were investigated in POE - Li Cl sub(7)O sub(4) and POE - Li BF sub(4) complexes. Our sup(1)H, Li and sup(19)F relaxation study suggest that cation motion is controlled by segmental motions of the polymer chain while the anion have additional mobility associated with BG sub(4) rotation. (author).

  6. WEB based user's applications for NA61/SHINE experiment at CERN

    CERN Document Server

    Piwek, Mateusz

    1. Introduction The Master Thesis titled „Web based users applications for NA61/SHINE experiment at CERN” presents the World Wide Web technologies that has been used during development of the software suite for NA61/SHINE experiment. Presented software was implemented and is use by a group of approximately sixty users 1 . The NA61/SHINE is one of many projects that takes place in the European Organization for Nuclear Research – CERN located near Geneva. 1.1. About CERN CERN (French: Organisation européenne pour la recherche nucléaire 2 ) was established on 29 th of September 1954. Poland is a member state since 1991, however a for a long time before joining CERN Poland as the only country of Communist Block had an observatory status. Nowadays Polish scientists are taking a part in a main CERN's experiments such as ALICE, ATLAS or CMS. CERN's essential scientific facilities are the particle physics accelerators and detectors. The beam provided by the accelerator or collider by interacting w...

  7. Magnetic resonance imaging in schizophrenia: a morphometric study; Ressonancia magnetica na esquizofrenia: um estudo morfometrico

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Claudio Campi de [Sao Paulo Univ., SP (Brazil). Instituto do Coracao (InCor). Secao de Ressonancia Magnetica]. E-mail: campi@uol.com.br

    2001-06-01

    Thirty-three patients with chronic schizophrenia and 21 normal subjects were submitted to magnetic resonance imaging studies using a 1.5 T scanner. Axial and coronal T 2-weighted images were obtained. The volumes of the brain, intracranial, supratentorial, infratentorial and the total, ventricular and subarachnoid cerebrospinal fluid volumes were measured using semi-automated morphometric methods. The volumes of the amygdala-hippocampus complex, para hippocampal gyrus cortex, putamen, globus pallidus, temporal lobe, gray and white matter of temporal lobe were also measured. These volumes were normalized using the intracranial volume as reference. The most relevant findings observed were reduced brain volume and increased total, ventricular and subarachnoid cerebrospinal fluid volumes in patients with schizophrenia when compared to the controls. Patients with schizophrenia had also smaller amygdala-hippocampus complexes, temporal lobes and temporal lobe white matter than the controls, as well as increased putamen volumes. (author)

  8. Altered Na+ transport after an intracellular alpha-subunit deletion reveals strict external sequential release of Na+ from the Na/K pump.

    Science.gov (United States)

    Yaragatupalli, Siddhartha; Olivera, J Fernando; Gatto, Craig; Artigas, Pablo

    2009-09-08

    The Na/K pump actively exports 3 Na(+) in exchange for 2 K(+) across the plasmalemma of animal cells. As in other P-type ATPases, pump function is more effective when the relative affinity for transported ions is altered as the ion binding sites alternate between opposite sides of the membrane. Deletion of the five C-terminal residues from the alpha-subunit diminishes internal Na(+) (Na(i)(+)) affinity approximately 25-fold [Morth et al. (2007) Nature 450:1043-1049]. Because external Na(+) (Na(o)(+)) binding is voltage-dependent, we studied the reactions involving this process by using two-electrode and inside-out patch voltage clamp in normal and truncated (DeltaKESYY) Xenopus-alpha1 pumps expressed in oocytes. We observed that DeltaKESYY (i) decreased both Na(o)(+) and Na(i)(+) apparent affinities in the absence of K(o)(+), and (ii) did not affect apparent Na(o)(+) affinity at high K(o)(+). These results support a model of strict sequential external release of Na(+) ions, where the Na(+)-exclusive site releases Na(+) before the sites shared with K(+) and the DeltaKESYY deletion only reduces Na(o)(+) affinity at the shared sites. Moreover, at nonsaturating K(o)(+), DeltaKESYY induced an inward flow of Na(+) through Na/K pumps at negative potentials. Guanidinium(+) can also permeate truncated pumps, whereas N-methyl-D-glucamine cannot. Because guanidinium(o)(+) can also traverse normal Na/K pumps in the absence of both Na(o)(+) and K(o)(+) and can also inhibit Na/K pump currents in a Na(+)-like voltage-dependent manner, we conclude that the normal pathway transited by the first externally released Na(+) is large enough to accommodate guanidinium(+).

  9. Ca/Na selectivity coefficients from the Poisson-Boltzmann theory

    International Nuclear Information System (INIS)

    Hedstroem, Magnus; Karnland, Ola

    2010-01-01

    Document available in extended abstract form only. A possible scenario in the post-glacial evolution of the bentonite buffer used in a KBS-3 repository for spent nuclear fuel is that parts of the buffer may erode due to sol formation caused by the extensive swelling of, in particular, Na-montmorillonite in water of low ionic strength. Presence of calcium in the interlayer has been shown to promote gel formation even in electrolytes with ionic strengths in the vicinity of those in glacial melt waters. In order to estimate the amount of calcium in the clay at the onset of glaciation one needs information of the selectivity coefficient for Ca/Na exchange. Hitherto, most experimental data for evaluating the Gaines-Thomas selectivity coefficient, K GT have been obtained in batch experiments, i.e. at high water-to-solid ratios. The conditions in highly compacted bentonite are, however, radically different in many respects, e.g. the interlayer space is on the nanometre scale and the concentration of counterions is in molar range. Therefore we would like to theoretically investigate the transferability of the selectivity coefficients, determined in batch experiments, to compacted conditions. We solve the Poisson-Boltzmann (PB) equation for two parallel charged surfaces in equilibrium with an external NaCl/CaCl 2 mixed solution. Integration of the ion concentration profiles obtained from the PB equation gives the occupancy of Na + and Ca 2+ in the clay. That information together with the composition of the external electrolyte is all that is needed for the calculation of K GT . With a surface layer-charge density of one charge per 145 A 2 , which is close to the value for Wyoming montmorillonite, we find a variation of the selectivity coefficient from about 4 M in batch to 8 M for compacted montmorillonite with dry density 1700 kg/m 3 . The significance as well as the physics behind these results will be presented in detail. The predictions, based on the PB theory, will

  10. Write up of the codes for microscopic models of NN and NA scattering

    International Nuclear Information System (INIS)

    Amos, K.

    1998-01-01

    This report documents the essential details of the NN and NA computer programs that culminate in the prediction of elastic and inelastic nucleon scattering observables form optical potentials generated by full folding and effective NN interaction within the nuclear medium. That same (energy and density dependent) effective interaction is used as the transition operator in the distorted wave approximation (DWA) for inelastic (and charge exchange) nucleon scattering from nuclei. The report consists of four sections: 1) general remarks and program locations, 2) the t- and g-matrix codes and how to use them, 3) the effective interaction codes and how to use them, and 4) the NA codes, DWBA97 and DWBB97 and how to use them. (author)

  11. Section for nuclear physics and energy physics - Annual report 1989

    International Nuclear Information System (INIS)

    1990-04-01

    The experimental activities in nuclear physics have in 1989 mainly been centered around the cyclotron laboratory with the Scanditronic MC-35 cyclotron. The installation of the CACTUS multidetector system has been completed. With 8 particle telescopes, 28 NaI detectors and 2 Ge detectors, this experimental arrangement represents a major improvement compared to earlier set-ups in the laboratory. Theoretical studies of manybody problems, and nuclear structure and reactions have continued. The study of problems related to the foundations of quantum mechanics has also been persued

  12. Research in nuclear reactor theory and experimental reactors; Istrazivanja u teoriji nuklearnih reaktora i ekspeimentalni reaktori

    Energy Technology Data Exchange (ETDEWEB)

    Pop-Jordanov, J [Elektrotehnicki fakultet, Beograd (Yugoslavia)

    1978-05-15

    The paper is devoted to the possibilities of using experimental reactors for scientific research in nuclear power with a stress on problems in nuclear reactor theory. The stationary and nonstationary neutron fields, burnup prediction and analyses as well as fuel element development and the corresponding role of test-reactors were dealt with. It was shown that the investigations in nuclear reactor theory in Yugoslavia were developing continuously and in a useful interaction with experiments on research reactors. The needs for continuing the work on fundamental problems in neutron transport theory and on improving the calculation methods for thermal power reactors, together with the improvement of performances of existing research systems, were pointed out. A new quality in scientific work could be obtained dealing with the problems connected to a possible introduction of test-reactors, and fast systems later on. It was also pleaded for the corresponding orientations in fundamental sciences. (author) Rad je posvecen mogucnostima koriscenja eksperimentalnih reaktora za naucna istrazivanja u nuklearnoj energetici, sa akcentom na probleme teorije nuklearnih reaktora. Obradjena su stacionarna i nestacionarna neutronska polja, predikcija i analize sagorevanja, kao i razvoj gorivnih elemenata te uloga test-reaktora u osvajanju njihove tehnologije. Pokazano je da su se istrazivanja u teoriji nuklearnih reaktora u nas odvijala kontinualno i u korisnoj interakciji sa eksperimentima na istrazivackim reaktorima. Istaknuta je potreba nastavljanja rada na fundamentalnim problemima transportne teorije neutrona i na usavrsavanju metoda proracuna termalnih enerrgetskih reaktora, uz poboljsanje performansi postojecih istrazivackih sistema. Novi kvalitet u naucnom radu bi predstavljala orijentacija na probleme vezane sa eventualnim uvodjenjem test-reaktora, a zatim i brzih sistema. Pledirano je i za odgovarajuca usmeravanja u fundamentalnim naukama. (author)

  13. Stress corrosion evaluation on stainless steel 304 pipes in Laguna Verde Nuclear Power Plant

    International Nuclear Information System (INIS)

    Arganis J, C.R.

    1996-01-01

    Inside the frame of the project IAEA/MEX-41044 'Stress corrosion as a starting event of accidents in nuclear plants', and of the institutional project IA-252 under the same name, it was required from the Laguna Verde Nuclear Plant, material equivalent to the one employed in the piping of the primary recycling system. Laguna Verde Nuclear Plant granted two tracks of tubes, that could be used to substitute the ones that are in operation, as is the tube SA-358TP304 CL-QC with transversal welding, designated as ER-316-LQA. According to the report entitles 'Revision of the operational experience related to corrosion in the nuclear plants' it was found that the stress corrosion is the principal mechanism of corrosion present in the nuclear plants. Previous records indicate that sensitized stainless steels are resistant to stress corrosion in testings of constant loading in sea water (3.5% of chlorides approximately) to 80 Centigrade and to 80% of the limit of conveyance and that a solution of 22% of NaCl to 90 Centigrade, produces cracking due to stress corrosion in highly sensitized steels, in tests of speed of slow extension (SSRT), to a speed of 1x10 -6 s -1 . Daniels reports that there is a direct relation between the speed limit of detection of the SSRT test and the concentration of chlorides, for stainless steels tested to 100 Centigrade. The minimum detection speed of susceptibility to stress corrosion for solution to 20% of NaCl, is of 1x10 -7 s -1 . Taking into account these considerations, the employment of a solution with 22% of NaCl to 90 Centigrade to a speed of 1x10 -6 s -1 seems a good choice for the evaluation of stainless steel. (Author)

  14. Active transport of Na+ by reconstituted Na,K-ATPase

    International Nuclear Information System (INIS)

    Boldyrev, A.A.; Svinukhova, I.A.

    1987-01-01

    The ability of ATP, CTP, ITP, GTP, and UTP to support ouabain-sensitive accumulation of Na + by proteoliposomes with a reconstituted Na/K-pump was investigated. At a low [Na + ]/[K + ] ratio in the medium (20 mM/50 mM), a correlation is observed between the proton-accepting capacity of the nucleotide and its effectiveness as a substrate of active transport. To test the hypothesis of the importance of the presence of a negative charge in the 1-position of the purine (3-pyrimidine) base of the nucleotide for mutual transitions between the Na- and K-conformations of Na,K-ATPase they used two analogs of ATP: N 1 -hydroxy-ATP, possessing proton acceptor capacity, and N 1 -methoxy-ATP, in the molecule of which the negative charge is quenched by a methyl group. The first substrate supports active accumulation of Na + in proteoliposomes at the same rate as ATP, whereas the second substrate is relatively ineffective

  15. Measurement of exchangeable sodium: 22Na or 24Na

    International Nuclear Information System (INIS)

    Smith, T.; Edmonds, C.J.

    1987-01-01

    A case is made for the use of 22 Na in low activities in preference to 24 Na for routine diagnostic estimation of exchangeable sodium, and is based chiefly on considerations of availability, cost and radiation dosimetry. A method in which only 37 kBq (1 μCi) 22 Na is administered orally is shown to be sufficiently accurate and to possess distinct advantages in terms of cost and convenience with a committed radiation dose no greater than that for a measurement using 24 Na. (author)

  16. Ouabain-induced internalization and lysosomal degradation of the Na+/K+-ATPase.

    Science.gov (United States)

    Cherniavsky-Lev, Marina; Golani, Ofra; Karlish, Steven J D; Garty, Haim

    2014-01-10

    Internalization of the Na(+)/K(+)-ATPase (the Na(+) pump) has been studied in the human lung carcinoma cell line H1299 that expresses YFP-tagged α1 from its normal genomic localization. Both real-time imaging and surface biotinylation have demonstrated internalization of α1 induced by ≥100 nm ouabain which occurs in a time scale of hours. Unlike previous studies in other systems, the ouabain-induced internalization was insensitive to Src or PI3K inhibitors. Accumulation of α1 in the cells could be augmented by inhibition of lysosomal degradation but not by proteosomal inhibitors. In agreement, the internalized α1 could be colocalized with the lysosomal marker LAMP1 but not with Golgi or nuclear markers. In principle, internalization could be triggered by a conformational change of the ouabain-bound Na(+)/K(+)-ATPase molecule or more generally by the disruption of cation homeostasis (Na(+), K(+), Ca(2+)) due to the partial inhibition of active Na(+) and K(+) transport. Overexpression of ouabain-insensitive rat α1 failed to inhibit internalization of human α1 expressed in the same cells. In addition, incubating cells in a K(+)-free medium did not induce internalization of the pump or affect the response to ouabain. Thus, internalization is not the result of changes in the cellular cation balance but is likely to be triggered by a conformational change of the protein itself. In physiological conditions, internalization may serve to eliminate pumps that have been blocked by endogenous ouabain or other cardiac glycosides. This mechanism may be required due to the very slow dissociation of the ouabain·Na(+)/K(+)-ATPase complex.

  17. Impact of nuclear data on sodium-cooled fast reactor calculations

    International Nuclear Information System (INIS)

    Aures, A.; Bostelmann, F.; Zwermann, W.; Velkov, K.

    2016-01-01

    Neutron transport and depletion calculations are performed in combination with various nuclear data libraries in order to assess the impact of nuclear data on safety-relevant parameters of sodium-cooled fast reactors. These calculations are supplemented by systematic uncertainty analyses with respect to nuclear data. Analysed quantities are the multiplication factor and nuclide densities as a function of burn-up and the Doppler and Na-void reactivity coefficients at begin of cycle. While ENDF/B-VII.0 / -VII.1 yield rather consistent results, larger discrepancies are observed between the JEFF libraries. While the newest evaluation, JEFF-3.2, agrees with the ENDF/B-VII libraries, the JEFF-3.1.2 library yields significant larger multiplication factors. (authors)

  18. Suppression of Na interstitials in Na-F codoped ZnO

    Science.gov (United States)

    Huo, Wenxing; Mei, Zengxia; Tang, Aihua; Liang, Huili; Du, Xiaolong

    2018-04-01

    Controlling the formation of interstitial Na (Nai) self-compensating defects has been a long-term physics problem for effective Na doping in ZnO. Herein, we present an experimental approach to the suppression of Nai defects in ZnO via Na and F codoping under an oxygen-rich condition during the molecular beam epitaxy growth process. It is found that the incorporation of such large numbers of Na and F dopants (˜1020 cm-3) does not cause an obvious influence on the lattice parameters. Hall-effect measurements demonstrate that F doping efficiently raises the Fermi level (EF) of ZnO films, which is expected to make the formation energy of Nai and NaZn increase and decrease, respectively. Most of the Na atoms occupy the substitutional Zn sites, and the formation of Nai is suppressed consequently. Secondary ion mass spectrometry measurements reveal that F and Na atoms are tightly bonded together due to their strong Coulomb interaction. The enhanced deep level emission (DLE) in ZnO:Na-F is ascribed to the considerable amount of isolated Zn vacancy (VZn) defects induced by the elevated EF and the formation of neutral (" separators="| FO + - Na Zn - ) 0 complexes. On the other hand, formation of (" separators="| FO + - VZn 2 - ) - complexes in ZnO:F exhausts most of the isolated Zn vacancies, leading to the disappearance of the DLE band.

  19. A Comparison between HPGe and NaI(Tl) detectors performance for gamma-spectrometry of low level measurement

    International Nuclear Information System (INIS)

    Poursiamy, N. H.; Tajikahmadi, H.; Mirshojaei, S. F.

    2005-01-01

    According to progressive usage of nuclear technology, it's important to prevent the contamination of the environment by man-made radioisotopes and exposures of human being. Radioisotopes can enter the human body by inhalation and ingestion which are the most important ways to internal exposures. Measurement of radiation level in foodstuff is one of the most important parameters in environmental safety which is performed according to constitution and standard tests in most countries such as Iran. Gamma spectrometry is carried out by NaI(Tl) and HPGe detector systems for foodstuffs. In this research operation of HPGe and NaI(Tl) detectors in gamma spectrometry with a standard radioactive source are investigated and compared. Also the result of NaI superiority in foodstuff radiation measurement given

  20. Sodium Iodide-131 (Na131I) AS Gelatin Capsules At TNRC-In Libya

    International Nuclear Information System (INIS)

    Sherief, M. F.; Abudeeb, F. N.; Abudaia, J. A.; Elghanoudy, Y. A.

    2004-01-01

    In this contribution, the production of a capsulated Na 131 I radiopharmaceutical, for treatment of variety of hyperthyroidism diseases, at Tajoura Nuclear Research Center in Tripoli-Libya is described. The process requires the application of a very small volume of iodine-131 (not more than 25μ l in some cases) with radioactivities reaching some 37 GBq per capsule. The application of such volume is necessary to prevent damage to gelatin material. Loading a volume of 100 μ l of radioactive Na 131 I solution containing 37 GBq. radioactivity within a capsule filled with anhydrous sodium hydrogen phosphate as an adsorption material for Na 131 I solution brings such solution into a direct interaction with the gelatin material. This is assumed to have an inadequate effect in therapy. To overcome this problem, the work team has introduced some substantial alterations on the irradiation procedure and the process of the pre-irradiation treatment of the target. As a consequence, that has successfully culminated in production of Na 131 I capsules with proper perspective (e.g. radioactive yield of 74 GBq from 37 GBq previously and radioactive concentration of 37 GBq/ml). (Authors)

  1. OGLAŠEVANJE NA DRUŽBENIH OMREŽJIH NA PRIMERU FACEBOOKA

    OpenAIRE

    Novak, Martina

    2012-01-01

    V diplomskem delu obravnavamo družbene medije kot novo priložnost za promocijo in oglaševanje podjetij. Spoznali smo družbena omrežja na splošno in nekaj teh, ki jih uporabljamo tudi v Sloveniji na kratko predstavili. Podrobneje smo se osredotočili na družbeno omrežje Facebook, predvsem na samo spletno stran, njen izgled in storitve, ki jih ponuja uporabnikom. V nalogi je podrobneje opisan Facebook kot orodje za uporabo oglaševanja. Spoznali smo brezplačne in plačljive načine promocije in ogl...

  2. Na+,K+-ATPase Na+ affinity in rat skeletal muscle fiber types

    DEFF Research Database (Denmark)

    Kristensen, Michael; Juel, Carsten

    2010-01-01

    Previous studies in expression systems have found different ion activation of the Na(+)/K(+)-ATPase isozymes, which suggest that different muscles have different ion affinities. The rate of ATP hydrolysis was used to quantify Na(+),K(+)-ATPase activity, and the Na(+) affinity of Na(+),K(+)-ATPase...

  3. Bose-Einstein correlations and the equation of state of nuclear matter in relativistic heavy-ion collisions

    International Nuclear Information System (INIS)

    Schlei, B.R.

    1998-01-01

    Experimental spectra of the CERN/SPS experiments NA44 and NA49 are fitted while using four different equations of state of nuclear matter within a relativistic hydrodynamic framework. For the freeze-out temperatures, T f = 139 MeV and T f = 116 MeV, respectively, the corresponding freeze-out hypersurfaces and Bose-Einstein correlation functions for identical pion pairs are discussed. It is concluded, that the Bose-Einstein interferometry measures the relation between the temperature and the energy density in the equation of state of nuclear matter at the late hadronic stage of the fireball expansion. It is necessary, to use the detailed detector acceptances in the calculations for the Bose-Einstein correlations

  4. Crystal structure of Na+, K(+)-ATPase in the Na(+)-bound state.

    Science.gov (United States)

    Nyblom, Maria; Poulsen, Hanne; Gourdon, Pontus; Reinhard, Linda; Andersson, Magnus; Lindahl, Erik; Fedosova, Natalya; Nissen, Poul

    2013-10-04

    The Na(+), K(+)-adenosine triphosphatase (ATPase) maintains the electrochemical gradients of Na(+) and K(+) across the plasma membrane--a prerequisite for electrical excitability and secondary transport. Hitherto, structural information has been limited to K(+)-bound or ouabain-blocked forms. We present the crystal structure of a Na(+)-bound Na(+), K(+)-ATPase as determined at 4.3 Å resolution. Compared with the K(+)-bound form, large conformational changes are observed in the α subunit whereas the β and γ subunit structures are maintained. The locations of the three Na(+) sites are indicated with the unique site III at the recently suggested IIIb, as further supported by electrophysiological studies on leak currents. Extracellular release of the third Na(+) from IIIb through IIIa, followed by exchange of Na(+) for K(+) at sites I and II, is suggested.

  5. Evaluation of 1cm dose equivalent rate using a NaI(Tl) scintilation spectrometer

    International Nuclear Information System (INIS)

    Matsuda, Hideharu

    1990-01-01

    A method for evaluating 1 cm dose equivalent rates from a pulse height distribution obtained by a 76.2mmφ spherical NaI(Tl) scintillation spectrometer was described. Weak leakage radiation from nuclear facilities were also measured and dose equivalent conversion factor and effective energy of leakage radiation were evaluated from 1 cm dose equivalent rate and exposure rate. (author)

  6. A construção da coordenação política e da cooperação estratégica entre o Brasil e Argentina na área nuclear (1980-1997)

    OpenAIRE

    Silva, Ana Paula da [UNESP

    2011-01-01

    O trabalho analisa o processo histórico do surgimento, desenvolvimento e consolidação da coordenação política e da cooperação estratégica entre Brasil e Argentina na área nuclear. Levando em conta a rivalidade existente entre os dois países, faz-se um exame das políticas interna e externa exercida por ambos, considerando ainda aspectos importantes da política regional e global, e de que maneira foram implantados os mecanismos para a superação da desconfiança mútua e estabelecimento da coopera...

  7. Meltability in system of K2TaF7-NaF-NaCl-KCl

    International Nuclear Information System (INIS)

    Kartsev, V.E.; Kovalev, F.V.; Korshunov, B.G.

    1975-01-01

    Thermographic and visual-polythermal techniques were used to study the meltability in K 2 TaF 7 -NaF-NaCl-KCl system. The tetrahedron-forming sections NaF-NaCl-K 2 TaF 7 xKCl and NaF-K 2 TaF 7 xKCl-2K 2 TaF 7 xNaCl divide the concentration tetrahedron into three particular tetrahedra: NaF-K 2 TaF 7 xKCl-2K 2 TaF 7 xNaCl-K 2 TaF 7 , NaF-NaCl-K 2 TaF 7 xKCl-2K 2 TaF 7 xaCl, and NaF-NaCl-KCl-K 2 TaF 7 xKCl. Non-variant equilibrium points in all of the particular four-component systems have been determined

  8. Qualitative characterization of free polyamines in ethyleneamines epoxide hardeners by nuclear magnetic resonance spectroscopy; Caracterizacion cualitativa de poliaminas libres en endurecedores de resinas epoxidicas del tipo etilenaminas por espectroscopia de resonancia magnetica nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Garcia, Filiberto [Universidade Federal de Itajuba (UNIFEI), MG (Brazil); Miguez, Eduardo; Tavares, Maria Ines B. [Universidade Federal do Rio de Janeiro (UFRJ/IMA), RJ (Brazil). Inst. de Macromoleculas Professora Eloisa Mano

    2008-01-15

    The qualitative characterization of two commercial ethyneamines epoxide hardeners marketed by ACROS (U.S.A.) was carried out by using carbon-13 nuclear magnetic resonance spectroscopy. The products were triethylenetetramine (TETA) and tetraethylenepentamine (TEPA). TETA had four components, the most important one being triethylenetetramine, an ethyleneamine of lineal structure, in a concentration of 60 mol%. Another component had ramified structure, while the other two exhibited recurrent structures of the piperazina type. TEPA had five components with similar structures. The major component was tetraethylenepentamine in an approximate concentration of 55 mol%. These results agree with the composition of similar products marketed by Dow Chemical Company, namely DEH 24 and DEH 26, respectively. (author)

  9. Nuclear methods in medicine

    International Nuclear Information System (INIS)

    Wolfe, D.M.

    1997-01-01

    Physicists have created remarkably sophisticated instruments for the performance of experiments. With variable phase lags many of these have become useful in technology. In the medical field NMD techniques have become commonplace under the rubric of Magnetic Resonance Imaging. Particle physics has developed sophisticated detectors for both charged and neutral particles. Many of these also have been adapted to medical uses. In both radiology and nuclear medicine, pixel detectors based on designs originating at large-scale colliders, are becoming highly useful in replacing film and NaI as the primary means of X-ray and (-ray detection. Coupled with high-speed work stations, these new techniques allow exciting new imagining modalities. Many of these are based on the handling of digital images originally developed for astronomy. Thus, once again, fundamental science is making large contributions to the development of technology. In this talk, various examples of developments in digital mammography and digital detectors for nuclear medicine will be given. The possibilities for telemedicine will be discussed. (author)

  10. Development of Al2O3 carrier-Ru composite catalyst for hydrogen generation from alkaline NaBH4 hydrolysis

    International Nuclear Information System (INIS)

    Huang, Yao-Hui; Su, Chia-Chi; Wang, Shu-Ling; Lu, Ming-Chun

    2012-01-01

    A recyclable and reusable Ru/Al 2 O 3 catalyst is prepared for hydrogen generation from the hydrolysis process of alkaline sodium borohydride (NaBH 4 ) solution. The hydrogen generation rate by the hydrolysis and methanolysis of alkaline NaBH 4 was explored as a function of NaOH concentration. Meantime, the byproducts derived from the spent alkaline NaBH 4 solution were characterized by X-ray diffraction (XRD), scanning electro microscope/energy dispersive spectrometer (SEM/EDS) and NMR (Nuclear Magnetic Resonance). The effect of NaOH concentration on the hydrogen generation from the hydrolysis of NaBH 4 significantly depends on the type of catalysts. With increasing NaOH concentration, the hydrogen generation rates decrease when using ruthenium (Ru) composite as a catalyst. The hydrogen generation rate of the methanolysis of NaBH 4 is significantly inhibited in the presence of NaOH as compared with the hydrolysis of NaBH 4 . The durability test of the Ru/Al 2 O 3 catalyst shows that the hydrogen generation rate decreases with recycling and reuse. The XRD and NMR analysis results show that the borate hydrate (NaBO 2 H 2 O) was derived from the hydrolysis of 20 wt% and 30 wt% NaBH 4 . -- Highlights: ► A recyclable Ru/Al 2 O 3 catalyst was synthesized for hydrogen generation. ► Ru/Al 2 O 3 significantly promotes the hydrogen generation rate from alkaline NaBH 4 solution. ► The prepared Ru/Al 2 O 3 catalyst can easily collect from the spent alkaline NaBH 4 solution.

  11. Active transport of Na/sup +/ by reconstituted Na,K-ATPase

    Energy Technology Data Exchange (ETDEWEB)

    Boldyrev, A.A.; Svinukhova, I.A.

    1987-02-20

    The ability of ATP, CTP, ITP, GTP, and UTP to support ouabain-sensitive accumulation of Na/sup +/ by proteoliposomes with a reconstituted Na/K-pump was investigated. At a low (Na/sup +/)/(K/sup +/) ratio in the medium (20 mM/50 mM), a correlation is observed between the proton-accepting capacity of the nucleotide and its effectiveness as a substrate of active transport. To test the hypothesis of the importance of the presence of a negative charge in the 1-position of the purine (3-pyrimidine) base of the nucleotide for mutual transitions between the Na- and K-conformations of Na,K-ATPase they used two analogs of ATP: N/sub 1/-hydroxy-ATP, possessing proton acceptor capacity, and N/sub 1/-methoxy-ATP, in the molecule of which the negative charge is quenched by a methyl group. The first substrate supports active accumulation of Na/sup +/ in proteoliposomes at the same rate as ATP, whereas the second substrate is relatively ineffective.

  12. Relationship between intracellular Na+ concentration and reduced Na+ affinity in Na+,K+-ATPase mutants causing neurological disease

    DEFF Research Database (Denmark)

    Toustrup-Jensen, Mads Schak; Einholm, Anja P.; Schack, Vivien

    The neurological disorders familial hemiplegic migraine type 2 (FHM2), alternating hemiplegia of childhood (AHC), and rapid-onset dystonia parkinsonism (RDP) are caused by mutations of Na+,K+-ATPase α2 and α3 isoforms, expressed in glial and neuronal cells, respectively. Although these disorders......, addressing the question to what extent they cause a change of the intracellular Na+ and K+ concentrations ([Na+]i and [K+]i) in COS cells. C-terminal extension mutants generally showed dramatically reduced Na+ affinity without disturbance of K+ binding, as did other RDP mutants. No phosphorylation from ATP...

  13. O espaço da energia nuclear no Brasil

    Directory of Open Access Journals (Sweden)

    Joaquim Francisco de Carvalho

    2012-01-01

    Full Text Available Este artigo repassa a história e descreve a experiência acumulada em energia nuclear no Brasil, mostrando que as aplicações biomédicas, industriais e agrícolas desenvolveram-se bem no país, a partir dos anos 1950. Em seguida, o artigo demonstra que o país pode cobrir seu consumo de energia elétrica apenas com fontes renováveis de energia, sem recorrer a usinas nucleares de potência. Por fim, são analisados os argumentos comuns na imprensa, a favor e contrários às centrais nucleares, e são discutidos alguns aspectos comerciais e políticos do problema. São também examinadas as estratégias de vendas da indústria nuclear no Brasil.This article reviews the history and describes the experience on nuclear energy in Brazil, showing that nuclear technology applied to biomedical sciences, industry and agriculture has been largely developed in this country, from the year 1950 on. Then the paper shows that Brazil can cover its electricity consumption with only renewable energy sources, without nuclear power plants. Finally the arguments usually employed in the press, pro and against nuclear power plants are analyzed and some commercial and political aspects of the problem are commented. The sales strategy of the nuclear industry in Brazil is also commented.

  14. MOŽNOSTI VSTOPA NA TUJE TRGE NA PRIMERU PODJETJA AWOODTURE

    OpenAIRE

    Orličnik, Urša

    2014-01-01

    Danes pojavljanje podjetja samo na domačem trgu ni več dovolj. Spremembe okolja, naraščanje konkurence ter hiter tehnološki napredek, silijo podjetja k nenehnemu prilagajanju in iskanju novih priložnosti tako na domačem kot tudi na tujem trgu. Internacionalizacija podjetja tako postaja vedno bolj pomemembna za preživetje podjetja. Internacionalizacija se v najširšem smislu nanaša na vse oblike mednarodnega ekonomskega sodelovanja. Je dinamičen proces, kateremu nujno sledi sprememba stanja...

  15. International conference on isotopic and nuclear analytical techniques for health and environment. Unedited papers

    International Nuclear Information System (INIS)

    2004-01-01

    The IAEA has been supporting nuclear and isotopic analytical techniques as part of its mandate to foster the peaceful uses of nuclear energy for many years. Nuclear analytical laboratories have been installed and upgraded through technical co-operation assistance in many laboratories of Member States. These techniques, including INAA, CRF, PIXE, stable isotopes and radioisotopes, α, β, γ spectrometry, Moessbauer spectrometry, etc., have been applied to a wide range of subjects with varying success. Nuclear analytical techniques, featuring some intrinsic quality control aspects, such as multi-nuclide analysis, frequently serve as 'reference methods' to crosscheck critical results. As nuclear properties of elements are targeted, matrix problems seem to be negligible. In light of its continued commitment and support, the IAEA organized the International Conference on Isotopic and Nuclear Analytical Techniques for Health and Environment. Out of 220 from 61 countries who applied for participation, 155 official participants and five observers from 47 countries were in attendance, with 67 from 32 developing countries and 21 from international organizations, including the World Health Organization. Eleven plenary sessions were held. Also conducted was a panel discussion on Human Capacity Development Needs in the Areas of Analytical Quality Control Services (AQCS), Radiochemistry and Nutrition. The scientific sessions were divided into several topics, which reflect some of the important activities of the IAEA's Department of Nuclear Sciences and Applications (NA): - Isotopic and nuclear techniques (general); - Metrology and quality assurance in nuclear measurements; - Nuclear analytical techniques for environmental monitoring; - Radioecology; - Environmental monitoring; - Radiological safety of food and water; - Methodological aspects of stable isotope techniques in health and environment; - Applications of isotopic techniques in health and environment; - New

  16. The role of nuclear energy in brazilian energy matrix: socioeconomic and environmental aspects; O papel da energia nuclear na matriz energetica brasileira: aspectos socioeconomicos e ambientais

    Energy Technology Data Exchange (ETDEWEB)

    Schirmer, Priscila

    2016-09-01

    With the large increase of energy demand in the world, either for the continued expansion of industrialization, or by the raise of consumption, are increasing the need for energy sources diversification and the search for cleaner alternatives of energy production. Nuclear power has been considered as an option to curb the emission of greenhouse gases and reduce the dependence of fossil fuels. However, nuclear energy is an issue that still causes a lot of doubt and questions, turning the development of this work very important for a better understanding of the lay public as well as to contribute and encourage future research through an assessment of their environmental and socio-economic aspects, discussing the risks, benefits, and an assessment of the expansion of nuclear energy use, including an overview of nuclear energy in Brazil. Concluding that nuclear energy can contribute to the expansion of the Brazilian energy matrix, as the only heat source able to ensure constant supply of energy without emitting greenhouse gases. Considering that Brazil dominates the technology of the nuclear fuel cycle, and has a large reserves of uranium. A larger share of nuclear energy in the Brazilian energy matrix can generate greater diversification of the same, valuing the environmental and economic sustainability of the country and reducing the system's vulnerability. However, nuclear generation should not be considered as the only solution to the energy problems of the country, but make a part of it by the combination with other renewable sources, increasing the diversity and energy security of the country. (author)

  17. Na/K pump inactivation, subsarcolemmal Na measurements, and cytoplasmic ion turnover kinetics contradict restricted Na spaces in murine cardiac myocytes

    OpenAIRE

    Lu, Fang-Min; Hilgemann, Donald W.

    2017-01-01

    The Na/K pump exports cytoplasmic Na ions while importing K ions, and its activity is thought to be affected by restricted intracellular Na diffusion in cardiac myocytes. Lu and Hilgemann find instead that the pump can enter an inactivated state and that inactivation can be relieved by cytoplasmic Na.

  18. Kaon production in intermediate-energy nuclear collisions

    International Nuclear Information System (INIS)

    Russkikh, V.N.; Ivanov, Yu.B.

    1992-01-01

    Production of positive kaons in nuclear collisions at intermediate energies (∝ 1-2 GeV/nucleon) is studied within the 3-dimensional fluid dynamics combined with the hadrochemical kinetics for strangeness production. Sensitivity of the kaon probe to a form of the nuclear equation of state is analyzed. The model reproduces total and differential cross sections of Ne+NaF→K + +X and Ne+Pb→K + +X reactions at E lab =2.1 GeV/nucleon, provided a soft equation of state is used. The pion-production data are also well described employing the same equation of state. Predictions are made for the current experiment on kaon production at the SIS accelerator. The obtained results are compared with the predictions of other models. (orig.)

  19. Cost-effectiveness of positive contrast and nuclear arthrography in patients who underwent total hip arthroplasty

    International Nuclear Information System (INIS)

    Swan, J.S.; Braunstein, E.M.; Capello, W.; Wellman, H.

    1989-01-01

    The authors have compared the cost effectiveness of contrast arthrography (CA) and nuclear arthrography (NA), in which In-111 chloride is injected with the contrast material, of total hip arthroplasties. Their series included 48 cases of surgically proved loose femoral components. The cost per true-positive result was obtained by taking the total cost of the examinations in surgically proved cases and dividing by the number of true-position cases. The cost of CA was $297 and the cost of NA was $335. For CA, the cost per true positive was $1,018, and for the NA the cost per true positive was $946. In spite of higher initial cost, NA is more cost effective than CA on a cost per true-positive case basis. NA is cost effective in evaluating hip arthroplasties in which there is suspicion of a loose femoral component

  20. Raman and X-ray absorption spectroscopic studies of hydrothermally altered alkali-borosilicate nuclear waste glass

    Energy Technology Data Exchange (ETDEWEB)

    McKeown, David A., E-mail: davidm@vsl.cua.ed [Vitreous State Laboratory, Catholic University of America, 620 Michigan Ave., N.E., Washington, DC 20064 (United States); Buechele, Andrew C.; Viragh, Carol; Pegg, Ian L. [Vitreous State Laboratory, Catholic University of America, 620 Michigan Ave., N.E., Washington, DC 20064 (United States)

    2010-04-01

    Raman spectroscopy and X-ray absorption spectroscopy (XAS) are used to characterize structural changes that took place in hydrothermally altered (Na,K)-alumina-borosilicate glasses with different Na/K ratios, formulated as part of a durability study to investigate the behavior of glasses for nuclear waste storage. The hydrothermal experiments, or vapor hydration tests (VHT), were performed on each glass for 3 and 20 days at 200 deg. C to accelerate and approximate long-term alteration processes that may occur in a nuclear waste repository. Results found for both glasses and their VHT altered counterparts show little, if any, structural influence from the different starting Na/K ratios. X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, and Raman spectroscopy indicate that the altered samples are mostly amorphous with small amounts of analcime-like and leucite-like crystals within 200 mum of the sample surface and contain up to 9.7 wt.% water or OH. The Raman data are nearly identical for the amorphous portions of all altered VHT samples investigated, and indicate that two glass structural changes took place during alteration: one, partial depolymerization of the alumina-borosilicate network, and two, introduction of water or OH. Al and Si XAS data indicate tetrahedral AlO{sub 4} and SiO{sub 4} environments in the original glasses as well as in the altered samples. Small energy shifts of the Si K-edge also show that the altered VHT samples have less polymerized networks than the original glass. Na XAS data indicate expanded Na environments in the VHT samples with longer Na-O distances and more nearest-neighbor oxygen atoms, compared with the original glasses, which may be due to hydrous species introduced into the expanding Na-sites.

  1. A compact HV supply for field/PC based nuclear instrumentation

    International Nuclear Information System (INIS)

    Manna, A.; Nikhare, D.M.; Madhavi, V.; Bayala, A.K.; Mukhopadhyay, P.K.; Kataria, S.K.

    2001-01-01

    In the recent years, most of the nuclear instruments that were earlier based on NIM Bin standards, are becoming available as PC Add-on cards. This trend is due to the decreasing prices of desktop personal computers and the necessity for automation in radioactivity measurements. This paper describes the design and development of a HV supply module and its PC Add-on card version for field portable/ PC based nuclear instrumentation. The HV supply though being very compact in size meets all the stringent specifications required for detector biasing applications and it has been tested for use with NaI, BF 3 . (author)

  2. Reinterpretando a cooperação nuclear entre Brasil e Argentina : as diversas nuances e perspectivas deste relacionamento no contexto mundial

    OpenAIRE

    Ricardo Medeiros de Castro

    2006-01-01

    A presente pesquisa analisa a validade de interpretações liberais relacionadas ao fenômeno cooperativo bilateral entre Brasil e Argentina no âmbito nuclear. A partir de uma contextualização abrangente, demonstra-se a forma como se arquitetou, na década de 80, a multilateralização das políticas externas nucleares dos referidos países, bem como apontam-se os ajustes destas políticas ocorridas na década de 90. Também, discute-se, neste trabalho, como aconteceu a adesão do Brasil e da Argentina e...

  3. Studies in Low-Energy Nuclear Science

    International Nuclear Information System (INIS)

    Brune, Carl R.; Grimes, Steven M.

    2006-01-01

    This report presents a summary of research projects in the area of low energy nuclear reactions and structure, carried out between 1 January 2003 and 31 December 2005 and supported by U.S. DOE grant number DE-FG03-03NA00074. Cross sections measured with high resolution have been subjected to an Ericson theory analysis to infer information about the nuclear level density. Other measurements were made of the spectral shape of particles produced in evaporation processes; these also yield level density information. A major project was the development of a new Hauser-Feshbach code for analyzing such spectra. Other measurements produced information on the spectra of gamma rays emitted in reactions on heavy nuclei and gave a means of refining our understanding of gamma-ray strength functions. Finally,reactions on light nuclei were studied and subjected to an R-matrix analysis. Cross sections fora network of nuclear reactions proceedingthrough a given compound nucleus shouldgreatly constrain the family of allowed parameters. Modifications to the formalism andcomputer code are also discussed.

  4. Selection of multislice in nuclear magnetic resonance tomography. Selecao de multiplos planos em tomografia por ressonancia magnetica nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Frare, Junior, P L

    1990-01-01

    The study and the implementation of three techniques for the selection of multislice, aiming the optimization of the NMR tomography is presented. The first technique uses the simultaneous excitation of multiple slices, being each plane encoded with a pre determined phase for a latter decodification of the information by the linear combination of n experiments. The second one makes use of the multislice simultaneous excitation, like the first one, but the slices are acquired in the presence of an oblique reading gradient, which provides us the multi slices signal without any further computer processing. The third technique uses frequency multiplexed excitation, that is, different slices are successively excited during the repetition time of an acquisition, making possible multislice acquisition at the same time of a single slice. The construction and the use of a phantom for the equipment characterization are discussed too. Many technical aspects necessary for an improvement of the tomography performance, like reception circuits and resonators, are discussed. A brief introduction to the gradient modulated adiabatic excitation (GMAX) technique and the first results ever obtained with it, using surface coils, is presented. (author).

  5. Characterization of an AtCCX5 gene from Arabidopsis thaliana that involves in high-affinity K+ uptake and Na+ transport in yeast

    International Nuclear Information System (INIS)

    Zhang, Xinxin; Zhang, Min; Takano, Tetsuo; Liu, Shenkui

    2011-01-01

    Highlights: → The AtCCX5 protein coding a putative cation calcium exchanger was characterized. → AtCCX5 expressed in yeast was localized in the plasma membrane and nuclear periphery. → AtCCX5 protein did not show the same transport properties as the CAXs. → AtCCX5 protein involves in mediating high-affinity K + uptake in yeast. → AtCCX5 protein also involves in Na + transport in yeast. -- Abstract: The gene for a putative cation calcium exchanger (CCX) from Arabidopsis thaliana, AtCCX5, was cloned and its function was analyzed in yeast. Green fluorescent protein-tagged AtCCX5 expressed in yeast was localized in the plasma membrane and nuclear periphery. The yeast transformants expressing AtCCX5 were created and their growth in the presence of various cations (K + , Na + , Ca 2+ , Mg 2+ , Fe 2+ , Cu 2+ , Co 2+ , Cd 2+ , Mn 2+ , Ba 2+ , Ni 2+ , Zn 2+ , and Li + ) were analyzed. AtCCX5 expression was found to affect the response to K + and Na + in yeast. The AtCCX5 transformant also showed a little better growth to Zn 2+ . The yeast mutant 9.3 expressing AtCCX5 restored growth of the mutant on medium with low K + (0.5 mM), and also suppressed its Na + sensitivity. Ion uptake experiments showed that AtCCX5 mediated relatively high-affinity K + uptake and was also involved in Na + transport in yeast. Taken together, these findings suggest that the AtCCX5 is a novel transport protein involves in mediating high-affinity K + uptake and Na + transport in yeast.

  6. Solubility and hydrolysis of Np(V) in dilute to concentrated alkaline NaCl solutions. Formation of Na-Np(V)-OH solid phases at 22 C

    Energy Technology Data Exchange (ETDEWEB)

    Petrov, Vladimir G. [Lomonosov Moscow State Univ. (Russian Federation). Dept. of Chemistry; Fellhauer, David; Gaona, Xavier; Dardenne, Kathy; Rothe, Joerg; Altmaier, Marcus [Karlsruhe Institute of Technology (Germany). Inst. for Nuclear Waste Disposal; Kalmykov, Stepan N. [Lomonosov Moscow State Univ. (Russian Federation). Dept. of Chemistry; NRC Kurchatov Institute, Moscow (Russian Federation)

    2017-03-01

    . Furthermore, the XRD pattern collected for one of the pink solid phases match the data recently reported for NaNpO{sub 2}(OH){sub 2}(cr). UV-vis/NIR spectra collected in 0.1-5.0 M NaCl solutions show the predominance of NpO{sub 2}{sup +} (≥80%) at pH{sub m} ≤ 10.3. This observation is consistent with the Np(V) hydrolysis scheme currently selected in the NEA-TDB. This work provides sound evidences on the formation of ternary Na-Np(V)-OH solid phases in Na-rich hyperalkaline solutions and ambient temperature conditions. Given the unexpectedly high complexity of the system, further experimental efforts dedicated to assess the thermodynamic properties of these solid phases are needed, especially in view of their likely relevance as solubility controlling Np(V) solid phases in Na-rich systems such as saline and cement-based environments in the context of the safety assessment for nuclear waste disposal.

  7. Investigation on the chirality of positrons from 22Na decay and their asymmetrical interactions with D-, L- and DL-alanines

    International Nuclear Information System (INIS)

    Conte, E.; Pieralice, M.

    1987-01-01

    An investigation on the chirality of the positrons from 22 Na and on their asymmetrical interactions with D-, L-, and DL-alanines was carried out. By using nuclear gamma-spectroscopy, the asymmetrical interaction was proved to be induced with a distinguishably asymmetrical effect

  8. Vpliv toplotnih mostov na porabo energije za ogrevanje na primeru osnovne šole

    OpenAIRE

    Megušar, Primož

    2015-01-01

    Na primeru Osnovne šole Dobrova sem preveril, kakšen vpliv imajo dejanski toplotni mostovi na porabo energije za ogrevanje. Iz načrtov stavbe sem evidentiral vse toplotne mostove, kateri vplivajo na porabo energije. Tem toplotnim mostovom sem nato v standardu SIST EN ISO 14683 poiskal ustrezne približke. Nato sem s programom TOST izvedel tri simulacije. V prvem primeru toplotnih mostov nisem upošteval. V drugem primeru sem toplotne mostove upošteval na poenostavljen način, v zadnjem primeru p...

  9. Na and K dependence of the Na/K pump in cystic fibrosis fibroblasts.

    OpenAIRE

    Reznik, V M; Schneider, J A; Mendoza, S A

    1981-01-01

    The Na and K dependence of the Na/K pump was measured in skin fibroblasts from patients with cystic fibrosis and age/sex-matched controls. Under basal conditions, there was no difference between control and cystic fibrosis cells in protein per cell, intracellular Na and K content, or Na/K pump activity (measured as ouabain-sensitive 86Rb uptake). There was no difference in the Na dependence of the Na/K pump between cystic fibrosis cells and control cells. In cells from patients with cystic fi...

  10. Vliv mikroflóry na senzorické vlastnosti vína

    OpenAIRE

    Petrášová, Ludmila

    2014-01-01

    Tato bakalářská práce se zabývá vlivem mikroflóry na senzorické vlastnosti vína. Teoretická část informuje o botanickém popisu hroznů vína Veltlínské zelené, dále o jeho složení, o technologii zpracování bílého vína a o vlivu kvasinek na aromatický profil vína. V další části popisuje metodu stanovení aromaticky aktivních látek pomocí plynové chromatografie v kombinaci s mikroextrakcí tuhou fází (SPME-GC). Cílem experimentální části bylo proměřit vzorky 4 různých moštů odrůdy Veltlínské zelené...

  11. Feasibility Study for the Measurement of Nuclear Fragmentation Cross Sections with NA61/SHINE at the CERN SPS

    CERN Document Server

    Aduszkiewicz, A

    2017-01-01

    A detailed knowledge of the fragmentation cross sections of intermediate mass nuclei is of paramount importance to understand the propagation of cosmic rays in our Galaxy and to evaluate the background for dark matter searches with space-based cosmic-ray experiments such as AMS. Therefore, we suggest a one-week test run in 2018 with secondary ions to establish the capabilities of NA61/SHINE to measure fragmentation cross sections at isotope level. No major modifications to the experimental setup of NA61/SHINE are needed to perform this feasibility study. The experience gained during the test run will be used to formulate a comprehensive measurement campaign for cosmic-ray related fragmentation cross sections for the possible extension of the NA61/SHINE physics program beyond 2020. The test data on carbon-proton and oxygen-proton interactions at 13A GeV/c that we intend to collect during the proposed test run have already the potential to reduce the current cross section uncertainties.

  12. Combined 18F-NaF and 18F-FDG PET/CT in the Evaluation of Sarcoma Patients.

    Science.gov (United States)

    Jackson, Tatianie; Mosci, Camila; von Eyben, Rie; Mittra, Erik; Ganjoo, Kristen; Biswal, Sandip; Gambhir, Sanjiv Sam; Iagaru, Andrei

    2015-09-01

    The combined administration of F-NaF and F-FDG in a single PET/CT scan has the potential to improve patient convenience and cancer detection. Here we report the use of this approach for patients with sarcomas. This is a retrospective review of 21 patients (12 men, 9 women; age, 19-66 years) with biopsy-proven sarcomas who had separate F-NaF PET/CT, F-FDG PET/CT, and combined F-NaF/F-FDG PET/CT scans for evaluation of malignancy. Two board-certified nuclear medicine physicians and 1 board-certified musculoskeletal radiologist were randomly assigned to review the scans. Results were analyzed for sensitivity and specificity, using linear regression and receiver operating characteristics. A total of 13 patients had metastatic disease on F-NaF PET/CT, F-FDG PET/CT, and combined F-NaF/F-FDG PET/CT. Skeletal disease was more extensive on the F-NaF PET/CT scan than on the F-FDG PET/CT in 3 patients, whereas in 1 patient, F-FDG PET/CT showed skeletal disease and the F-NaF PET/CT was negative. Extraskeletal lesions were detected on both F-FDG and combined F-NaF/F-FDG PET/CT in 20 patients, with 1 discordant finding in the lung. The combined F-NaF/F-FDG PET/CT scan allows for accurate evaluation of sarcoma patients. Further evaluation of this proposed imaging modality is warranted to identify the most suitable clinical scenarios, including initial treatment strategy and evaluation of response to therapy.

  13. Ginkgo biloba extract alters the binding of the sodium [123I] iodide (Na123I) on blood constituents

    International Nuclear Information System (INIS)

    Aleixo, Luiz Cláudio Martins; Moreno, Silvana Ramos Farias; Freitas, Rosimeire de Souza; Thomaz, Hélio; Santos-Filho, Sebastião David

    2012-01-01

    We evaluated the in vitro effect of an aqueous extract of Ginkgo biloba (EGb) on the distribution in blood cells (BC) and plasma (P) and on the binding of Na 123 I to the blood constituents using precipitation with trichloroacetic acid. The radioactivity percentages insoluble (SF) and insoluble fraction (IF) of blood constituents were determined. The EGb interfered (p 123 I in the P (from 69.64 to 86.13) and BC (from 30.36 to 13.87) and altered the fixation of the Na 123 I in IF-P and in IF-BC. - Highlights: ► Interaction between the Ginkgo biloba and blood constituents radiolabeled. ► Modification of the binding of sodium iodide (Na 123 I) to the blood constituents. ► This alteration should have influence in a diagnosis of nuclear medicine.

  14. Utility of Social Modeling in Assessment of a State's Propensity for Nuclear Proliferation

    International Nuclear Information System (INIS)

    Coles, Garill A.; Brothers, Alan J.; Whitney, Paul D.; Dalton, Angela C.; Olson, Jarrod; White, Amanda M.; Cooley, Scott K.; Youchak, Paul M.; Stafford, Samuel V.

    2011-01-01

    This report is the third and final report out of a set of three reports documenting research for the U.S. Department of Energy (DOE) National Security Administration (NASA) Office of Nonproliferation Research and Development NA-22 Simulations, Algorithms, and Modeling program that investigates how social modeling can be used to improve proliferation assessment for informing nuclear security, policy, safeguards, design of nuclear systems and research decisions. Social modeling has not to have been used to any significant extent in a proliferation studies. This report focuses on the utility of social modeling as applied to the assessment of a State's propensity to develop a nuclear weapons program.

  15. Energia nuclear na mídia: Jornalismo científico em portais de notícias nacionais

    Directory of Open Access Journals (Sweden)

    Ricardo Henrique Almeida Dias

    2017-07-01

    Full Text Available This study seeks to examine how the nuclear energy is conveyed by the news media. We used the newsworthiness criteria in journalistic discourse to analyse some science journalism texts on nuclear energy in Brazilian news websites. We selected some news and classified using news values such as conflict, proximity, novelty and relevance. We concluded that nuclear energy is conveyed by the media in a way that the advantages and disadvantages were discussed, and news values were useful to point how all these arguments worked.

  16. NCT program at Nuclear Medicine, Inc

    International Nuclear Information System (INIS)

    Noonan, D.J.

    1986-01-01

    The Neutron Capture Therapy program at Nuclear Medicine, Inc. (NMI) is focused on obtaining Food and Drug Administration (FDA) approval of the treatment for malignant brain tumors. To minimize both the time and expense of the approval process, research efforts have been strictly focused and Orphan Drug sponsorship of the boron compound, Na 2 B 12 H 11 SH, has been obtained. The significance of Orphan Drug sponsorship and NMI's initial meeting with the FDA to discuss preclinical and clinical protocols are discussed. 9 references, 2 figures

  17. Simulation of the peak efficiency for a stacked NaI(Tl) spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, H; Murohka, H; Anami, K; Nohtomi, A; Uozumi, Y; Sakae, T; Matoba, M [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering; Koori, N; Maki, T

    1996-07-01

    A stacked NaI(Tl) spectrometer has been developed to measure proton spectra in wide energy range. In the measurement of charged particles with intermediate energy, the detecting efficiency of the spectrometer decreases considerably due to nuclear reactions or out-scattering in the detector material. A Monte Carlo simulation code has been developed to estimate the peak efficiency (peak-to-total ratio) of the spectrometer. The calculated efficiency for intermediate energy is in good agreement with the experimental one. (author)

  18. 18F-NaF PET/CT: EANM procedure guidelines for bone imaging

    International Nuclear Information System (INIS)

    Beheshti, M.; Langsteger, W.; Mottaghy, F.M.; Payche, F.; Behrendt, F.F.F.; Wyngaert, T.V. den; Fogelman, I.; Strobel, K.; Celli, M.; Fanti, S.; Giammarile, F.; Krause, B.

    2015-01-01

    The aim of this guideline is to provide minimum standards for the performance and interpretation of 18 F-NaF PET/CT scans. Standard acquisition and interpretation of nuclear imaging modalities will help to provide consistent data acquisition and numeric values between different platforms and institutes and to promote the use of PET/CT modality as an established diagnostic modality in routine clinical practice. This will also improve the value of scientific work and its contribution to evidence-based medicine. (orig.)

  19. Investigating the influence of Na+ and Sr2+ on the structure and solubility of SiO2-TiO2-CaO-Na2O/SrO bioactive glass.

    Science.gov (United States)

    Li, Y; Placek, L M; Coughlan, A; Laffir, F R; Pradhan, D; Mellott, N P; Wren, A W

    2015-02-01

    This study was conducted to determine the influence that network modifiers, sodium (Na+) and strontium (Sr2+), have on the solubility of a SiO2-TiO2-CaO-Na2O/SrO bioactive glass. Glass characterization determined each composition had a similar structure, i.e. bridging to non-bridging oxygen ratio determined by X-ray photoelectron spectroscopy. Magic angle spinning nuclear magnetic resonance (MAS-NMR) confirmed structural similarities as each glass presented spectral shifts between -84 and -85 ppm. Differential thermal analysis and hardness testing revealed higher glass transition temperatures (Tg 591-760 °C) and hardness values (2.4-6.1 GPa) for the Sr2+ containing glasses. Additionally the Sr2+ (~250 mg/L) containing glasses displayed much lower ion release rates than the Na+ (~1,200 mg/L) containing glass analogues. With the reduction in ion release there was an associated reduction in solution pH. Cytotoxicity and cell adhesion studies were conducted using MC3T3 Osteoblasts. Each glass did not significantly reduce cell numbers and osteoblasts were found to adhere to each glass surface.

  20. Characterization of functional polymers by NMR; Caracterizacao de polimeros funcionalizados por ressonancia magnetica nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Neto, Oscar H.S. A.S.; San Gil, Rosane A.S.; Nakayama, T; Costa Neto, Claudio [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica

    1994-12-31

    Several synthetic polymers are used in the chemical analysis of complexes mixtures aiming to extract certain specific functional groups for further identification. This work describes the utilization of NMR in the characterization of one of the above mentioned compounds which will be used as reagent for the synthesis of another compound of the same type, which will be further used in the chemical analysis of alcohols and phenols. The methodology is described. The results are described and discussed 4 refs., 2 figs.

  1. Characterization of natural bentonite by NMR; Caracterizacao de bentonitas naturais por ressonancia magnetica nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Leite, Sidnei Q.M.; Dieguez, Lidia C [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia; Menezes, Sonia M.C. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas; San Gil, Rosane A.S. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica

    1994-12-31

    Solid state NMR as well as several other instrumental chemical analysis techniques were used in order to characterize two natural occurring bentonite. The methodology is described. The NMR spectra, together with the other used techniques suggest that the observed differences are due to iron inclusions in tetrahedral and octahedral sites 5 refs., 3 figs., 5 tabs.

  2. Site-specific induction of nuclear anomalies (apoptotic bodies and micronuclei) by carcinogens in mice

    International Nuclear Information System (INIS)

    Ronen, A.; Heddle, J.A.

    1984-01-01

    The usefulness of nuclear anomalies (NA) as a short-term test for indication of carcinogens in the mouse colon has been suggested previously by experiments in which colon-specific carcinogens induced NA in the colon, whereas non-colon carcinogens were, in general, impotent in that organ. We have extended this work to other sites in the digestive tract of female C57BL/6 mice treated with gamma-rays, 1,2-dimethylhydrazine dihydrochloride, or N-methylnitrosourea. Each agent induced NA at all of the sites examined. The frequency of NA at different times after treatment depended upon both the agent used and the site examined. 1,2-Dimethylhydrazine dihydrochloride (which is known to induce tumors predominantly in the colon) induces NA with the highest efficiency (relative to gamma-rays) in the descending colon. N-Methylnitrosourea (which induces tumors mainly in the forestomach) induces NA with the highest efficiency in the forestomach. These results further support the usefulness of the assay in that the frequency of NA produced at the various sites by 1,2-dimethylhydrazine dihydrochloride and N-methylnitrosourea correlates with that found in the carcinogenicity studies

  3. Nuclear magnetic resonance system with continuous flow of polarized water to obtain the traceability to static magnetic fields; Sistema de ressonancia magnetica nuclear com fluxo continuo de agua polarizada para obtencao da rastreabilidade para campos magneticos estaticos

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Ramon Valls; Nazarre, Diego Joriro, E-mail: ramon@ipt.br [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil)

    2013-07-01

    We have developed a system to obtain the traceability of field or magnetic induction intensity in the range of 2 μT up to 2 T, even in the presence of magnetic field gradients or noisy environments. The system is based on a nuclear magnetic resonance magnetometer, built in streaming water. The calibration procedure of a coil for magnetic field generation is described, as well as the results obtained and the estimated uncertainty (author)

  4. Chemical and mineralogical aspects of water-bentonite interaction in nuclear fuel disposal conditions

    International Nuclear Information System (INIS)

    Melamed, A.; Pitkaenen, P.

    1996-01-01

    In the field of nuclear fuel disposal, bentonite has been selected as the principal sealing and buffer material for placement around waste canisters, forming both a mechanical and chemical barrier between the radioactive waste and the surrounding ground water. Ion exchange and mineral alteration processes were investigated in a laboratory study of the long-term interaction between compacted Na-bentonite (Volclay MX-80) and ground water solutions, conducted under simulated nuclear fuel disposal conditions. The possible alteration of montmorillonite into illite has been a major object of the mineralogical study. However, no analytical evidence was found, that would indicate the formation of this non-expandable clay type. Apparently, the change of montmorillonite from Na- to Ca-rich was found to be the major alteration process in bentonite. In the water, a concentration decrease in Ca, Mg, and K, and an increase in Na, HCO 3 and SO 4 were recorded. The amount of calcium ions available in the water was considered insufficient to account for the recorded formation of Ca-montmorillonite. It is therefore assumed that the accessory Ca-bearing minerals in bentonite provide the fundamental source of these cations, which exchange with sodium during the alteration process. (38 refs.)

  5. Experimental study of the 22Ne(p,γ)23Na reaction and its implications for novae scenarios

    International Nuclear Information System (INIS)

    Menzel, Marie-Luise

    2013-01-01

    The 22 Ne(p,γ) 23 Na reaction belongs to the catalytic neon-sodium cycle and has an important role in the explosive hydrogen burning. The neon-sodium cycle takes place at temperatures of T = 0.1 - 0.5 GK and is assumed to occur in different astrophysical systems: e.g. in novae, in super novae of type Ia and during the shell-burning of red giant branch stars. The implications of 22 Ne(p,γ) 23 Na and the neon-sodium cycle in a nova scenario have been studied by using the nuclear network code libnucnet at GSI in Darmstadt. A nova is an outburst of matter in a binary system consisting of a white dwarf and a red giant star. It is therefore a representative phenomenon for explosive hydrogen burning. For the calculation of the nucleosynthesis during the nova outburst, the code libnucnet requires the initial mass composition of the novae partners, the temperature and density profiles of the nova explosion and the thermonuclear reaction rates of the participating reactions. In the following, the code determined the flow and the final atomic abundance in the neon-sodium cycle during the entire nova process. Additionally, the influence of the temperature profile of the novae outburst as well as the thermonuclear reaction rate of the 22 Ne(p,γ) 23 Na reaction on the final atomic abundance in the outburst has been studied. A characteristic measure for the reactions in astrophysical environments is the thermonuclear reaction rate. The reaction rate of 22 Ne(p,γ) 23 Na has still strong uncertainties in the temperature range of T = 0.03 - 0.3 GK. These uncertainties are based on insufficient upper limits of the resonance strengths as well as the possible existence of tentative states that are populated in the energy range of E lab p = 30 - 300 keV. The research presented in this thesis is dedicated to the experimental study of the 22 Ne(p,γ) 23 Na reaction for an improved determination of the thermonuclear reaction rate. Furthermore, the implications of 22 Ne(p,γ) 23 Na and

  6. Study of the Na-C-O and Na-H-O ternary systems in the sodium rich corner

    International Nuclear Information System (INIS)

    Maupre, J.-P.

    1978-02-01

    The purpose of this study is to provide a contribution to the understanding of the sodium - carbon - oxygen and sodium - hydrogen - oxygen ternary systems in the sodium rich corner. In order to do this the Na-NaH-Na 2 O-NaOH phase diagram was completed and the Na-Na 2 O-Na 2 CO 3 -C phase diagram was outlined. This work is made up of two parts. The first is devoted to a critical literature survey essential to establish correct phase diagrams. The second is an experimental study followed by a discussion collating our finding to the literary data. The basic experimental technique used is differential thermal analysis (DTA) but it has been completed by quenching, X-ray and chemical analysis methods. The proposed phase diagrams imply that Na-NaH-Na 2 O-NaOH and Na-Na 2 O-Na 2 CO 3 -C systems are reciprocal ternary systems. Temperatures of stable pairs reversal are respectively 410 and 690 0 C. The stable pairs are Na-NaOH and Na-Na 2 CO 3 at elevated temperature, Na 2 O-NaH and Na 2 O-C at low temperature [fr

  7. Response of saliva Na/K ratio to changing Na supply of lactating cows under tropical conditions.

    Science.gov (United States)

    Thiangtum, Wandee; Schonewille, J Thomas; Verstegen, Martin Wa; Arsawakulsudhi, Supot; Rukkwamsuk, Theera; Hendriks, Wouter H

    2017-06-01

    Factorial determination of the sodium (Na) requirement of heat-stressed lactating cows is hindered by accurate estimates of the Na losses through sweat. Direct studies, therefore, may be needed requiring information on the time course of healthy animals to become Na depleted and the subsequent rate of repletion. The rate of Na depletion and subsequent rate of Na repletion with two levels of dietary Na to lactating dairy cows housed under tropical conditions were investigated using the salivary Na/K. The 12 lactating cows (salivary Na/K ratio 14.6) rapidly developed clinical signs of Na deficiency, including pica, polyuria and polydipsia, reduced body weight and reduced milk yield when fed a low-Na ration (0.33 g kg -1 dry matter (DM)) for 3 weeks. Deficiency symptoms were associated with a rapid decrease in salivary Na/K ratio to cows with NaCl to a ration concentration of 1.1 or 1.6 g Na kg -1 DM for 5 weeks did not restore salivary Na/K ratio to values of >6. A daily Na intake of heat-stressed lactating cows to a ration intake of 1.6 g Na kg -1 DM was insufficient to restore Na deficiency. One week was sufficient to deplete heat-stressed lactating cows of Na, allowing for rapid dose-response studies utilizing the salivary Na/K ratio as a parameter for Na status of cows under tropical conditions. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  8. Nuclear astrophysics at ISAC with DRAGON: Initial studies

    International Nuclear Information System (INIS)

    Olin, Art; Bishop, Shawn; D'Auria, John M.; Lamey, Michael; Liu, Wenjie; Wrede, Chris; Buchmann, Lothar; Chen, Alan; Hunter, Don; Laird, Alison M.; Ottewell, Dave; Rogers, Joel; Chatterjee, Mohan L.; Engel, Sabine; Strieder, Frank; Gigliotti, Dario; Hussein, Ahmed; Greife, Uwe; Jewett, Cybele; Hutcheon, Dave

    2002-01-01

    The new DRAGON recoil separator facility, designed and built to measure directly the rates of radiative proton and alpha capture reactions important for nuclear astrophysics, is now in operation at the TRIUMF-ISAC radioactive beams facility in Vancouver, Canada. Experiments have been conducted for the first time on the 21Na(p,γ)22Mg reaction. The evolution of nova explosions, and particularly their 22Na abundance, depends sensitively on this reaction rate. The radioactive 21Na beam with an intensity of up to 5 x 108 /s was directed onto a windowless hydrogen gas target (3.8 x 1018 H atoms/cm2). Prompt reaction gamma rays were detected using a BGO array and separated reaction products detected using a silicon strip detector at the end of the 20.8 m recoil mass separator. Yield measurements recording simultaneously singles and coincident signals were performed by scanning in energy over the known resonance reported previously in 22Mg at Ecm = 212 keV, and in addition, over a strong resonance observed at Ecm ≅822 keV. Known resonances in the 21Ne(p,γ)22Na, 20Ne(p,γ)21Na, and 24Mg(p,γ)25Al reactions have been used to calibrate the DRAGON. Studies are in progress to further define the performance of the DRAGON facility. Status of the data analysis and results from system performance studies will be presented along with a brief description of the new ISAC and DRAGON facilities

  9. Prototype tests for the liquid Krypton, Calorimeter of the CP-violation Experiment NA48

    CERN Document Server

    Viehauser, Georg

    This work 1s the result of a one year stay as a technical student in the NA48 group at the European Center for Nuclear Research CERN from May 1992 to May 1993. The NA48 experiment is a fixed target experiment at the CERN Super Proton Synchrotron (SPS) to study direct CP violation in neutral kaon decays. The aim of the experiment is the measurement of the ratio of the CP violation parameters £ '/£. Chapter 1 will explain the origin of these parameters and our current knowledge of their size. Chapter 2 will give a description of the NA48 experiment. A crucial part of the experiment will be a photon calorimeter filled with liquid krypton. It has to meet very ambitious demands concerning the high rate capability and the energy, space and time resolutions. In chapter 3 the principles of electromagnetic calorimetry and ionization chambers are reviewed. In 1992 two test beam exposures of a prototype of the liquid krypton calorimeter were performed. A description of these tests will be given in chapter 4. During th...

  10. Dobutamine cine magnetic resonance imaging after myocardial infarction; Cine Risonanza Magnetica con dobutamina dopo infarto del miocardio

    Energy Technology Data Exchange (ETDEWEB)

    Giovagnoni, A.; Ligabue, G.; Romagnoli, R. [Modena Univ., Modena (Italy). Scienze Radiologiche, Dipt. di Medicina Interna; Reggio Emilia Univ., Reggio Emilia (Italy). Cattedra di Cardiologia; Rossi, R.; Muia, N.; Modena, M.G. [Modena Univ., Modena (Italy). Dipt. di Scienze Mediche, Oncologiche e Radiologiche; Reggio Emilia Univ. (Italy). Dipt. di Scienze Mediche, Oncologiche e Radiologiche

    1999-12-01

    . [Italian] La cine Risonanza Magnetica (cine RM) con stimolo farmacologico {beta}-adrenergico (stress dobutamina) rappresenta una nuova indagine diagnostica nella valuazione pretrattamento di rivascolarizzazione del paziente con infarto del miocardio. Scopo dello studio e' quello di verificare la validita' diagnostica della cine RM con stimolo farmacologico in confronto con l'ecocardiografia con stimolo farmacologico nella valutazione della vitalita' del miocardio e di proporre un nuovo metodo d'analisi delle immagini di cine RM mediante la sottrazione elettronica d'immagine al fine di ridurre gli elementi soggettivi nella valutazione quantitativa dell'ispessimento parietale. Ventisei pazienti (21 maschi, 5 femmine) con pregresso infarto del miocardio in attesa di intervento di rivascolarizzazione sono stati sottoposti a ecocardiografia con stimolo farmacologico mediante dobutamina e a esame cine RM con dobutamina al fine di verificare la ripresa contrattile dei segmenti giudicati acinetici o ipocinetici all'esame ecocardiografico di base. E' stata infusa dobutamina a dosi crescenti (5, 10, 15{gamma}/kg/min). Per ogni paziente sono stati considerati 16 segmenti del ventricolo sinistro. Nel totale di 416 segmenti miocardici considerati l'analisi qualitativa del movimento parietale con ecocardiografia con dobutamina ha dimostrato 307 segmenti normocinetici, 64 cicatriziali e 45 vitali mentre con la cine Rm sono stati osservati rispettivamente 302 segmenti come normocinetici, 83 cicatriziali e 31 vitali. Tre mesi dopo l'intervento di rivascolarizzazione 15 pazienti sono stati rivalutati per verificare la ripresa contrattile dei segmenti giudicati vitali. L'esame ecocardiografico ha mostrato sensibilita' del 79% e specificita' del 97% mentre per l'analisi qualitativa mediante cine RM la sensibilita' e' stata del 96% e la specificita' dell'86%. Nei pazienti con infarto anterosettale l

  11. Passivity of alloy C-22 in NaCl solutions

    International Nuclear Information System (INIS)

    Rodriguez, Martin A.; Carranza, Ricardo M.

    2004-01-01

    Alloy C-22 has been proposed as the corrosion resistant barrier of high-level waste nuclear containers. This alloy must be resistant to corrosion in multi-ionic solutions for a period of time as long as 10,000 years. The aim of the present work was to study the corrosion behavior of alloy C-22 in NaCl solutions. General and crevice corrosion were studied by means of electrochemical techniques. Open circuit potential was measured over the time, electrochemical impedance spectroscopy (EIS) measurements were carried out at open circuit and passivity potentials, as well as cyclic potentiodynamic polarization curves. Corrosion rates obtained by EIS measurements were acceptable for a waste nuclear container ( P ) values increased with open circuit potential and polarization time at constant potential. This was attributed to an increase in oxide film thickness and its aging respectively. The passive oxide form on alloy C-22 at the studied conditions presented a n-type semiconductor behavior in the passive potential range. Repassivation potential values (E R1 ) were determined for alloy C-22 at the studied conditions using PCA probes. (author) [es

  12. Project and construction of a measurement system and nuclear radiations analysis

    International Nuclear Information System (INIS)

    Castro, R. B. de.

    1983-01-01

    A counting system was designed and built, aiming to: detect and measure nuclear radiations using a Geiger-Mueller counter; and to measure the amplitudes of pulses from either a proportional or a NaI detector. The results obtained of the Cs-137 and Co-60 energy spectra were compared with results obtained from other researches. (Author) [pt

  13. Utility of Social Modeling in Assessment of a State’s Propensity for Nuclear Proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Coles, Garill A.; Brothers, Alan J.; Whitney, Paul D.; Dalton, Angela C.; Olson, Jarrod; White, Amanda M.; Cooley, Scott K.; Youchak, Paul M.; Stafford, Samuel V.

    2011-06-01

    This report is the third and final report out of a set of three reports documenting research for the U.S. Department of Energy (DOE) National Security Administration (NASA) Office of Nonproliferation Research and Development NA-22 Simulations, Algorithms, and Modeling program that investigates how social modeling can be used to improve proliferation assessment for informing nuclear security, policy, safeguards, design of nuclear systems and research decisions. Social modeling has not to have been used to any significant extent in a proliferation studies. This report focuses on the utility of social modeling as applied to the assessment of a State's propensity to develop a nuclear weapons program.

  14. Glutathionylation-Dependence of Na+-K+-Pump Currents Can Mimic Reduced Subsarcolemmal Na+ Diffusion

    Science.gov (United States)

    Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald J.; Rasmussen, Helge H.

    2016-01-01

    The existence of a subsarcolemmal space with restricted diffusion for Na+ in cardiac myocytes has been inferred from a transient peak electrogenic Na+-K+ pump current beyond steady state on reexposure of myocytes to K+ after a period of exposure to K+-free extracellular solution. The transient peak current is attributed to enhanced electrogenic pumping of Na+ that accumulated in the diffusion-restricted space during pump inhibition in K+-free extracellular solution. However, there are no known physical barriers that account for such restricted Na+ diffusion, and we examined if changes of activity of the Na+-K+ pump itself cause the transient peak current. Reexposure to K+ reproduced a transient current beyond steady state in voltage-clamped ventricular myocytes as reported by others. Persistence of it when the Na+ concentration in patch pipette solutions perfusing the intracellular compartment was high and elimination of it with K+-free pipette solution could not be reconciled with restricted subsarcolemmal Na+ diffusion. The pattern of the transient current early after pump activation was dependent on transmembrane Na+- and K+ concentration gradients suggesting the currents were related to the conformational poise imposed on the pump. We examined if the currents might be accounted for by changes in glutathionylation of the β1 Na+-K+ pump subunit, a reversible oxidative modification that inhibits the pump. Susceptibility of the β1 subunit to glutathionylation depends on the conformational poise of the Na+-K+ pump, and glutathionylation with the pump stabilized in conformations equivalent to those expected to be imposed on voltage-clamped myocytes supported this hypothesis. So did elimination of the transient K+-induced peak Na+-K+ pump current when we included glutaredoxin 1 in patch pipette solutions to reverse glutathionylation. We conclude that transient K+-induced peak Na+-K+ pump current reflects the effect of conformation-dependent β1 pump subunit

  15. Glutathionylation-Dependence of Na(+)-K(+)-Pump Currents Can Mimic Reduced Subsarcolemmal Na(+) Diffusion.

    Science.gov (United States)

    Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald J; Rasmussen, Helge H

    2016-03-08

    The existence of a subsarcolemmal space with restricted diffusion for Na(+) in cardiac myocytes has been inferred from a transient peak electrogenic Na(+)-K(+) pump current beyond steady state on reexposure of myocytes to K(+) after a period of exposure to K(+)-free extracellular solution. The transient peak current is attributed to enhanced electrogenic pumping of Na(+) that accumulated in the diffusion-restricted space during pump inhibition in K(+)-free extracellular solution. However, there are no known physical barriers that account for such restricted Na(+) diffusion, and we examined if changes of activity of the Na(+)-K(+) pump itself cause the transient peak current. Reexposure to K(+) reproduced a transient current beyond steady state in voltage-clamped ventricular myocytes as reported by others. Persistence of it when the Na(+) concentration in patch pipette solutions perfusing the intracellular compartment was high and elimination of it with K(+)-free pipette solution could not be reconciled with restricted subsarcolemmal Na(+) diffusion. The pattern of the transient current early after pump activation was dependent on transmembrane Na(+)- and K(+) concentration gradients suggesting the currents were related to the conformational poise imposed on the pump. We examined if the currents might be accounted for by changes in glutathionylation of the β1 Na(+)-K(+) pump subunit, a reversible oxidative modification that inhibits the pump. Susceptibility of the β1 subunit to glutathionylation depends on the conformational poise of the Na(+)-K(+) pump, and glutathionylation with the pump stabilized in conformations equivalent to those expected to be imposed on voltage-clamped myocytes supported this hypothesis. So did elimination of the transient K(+)-induced peak Na(+)-K(+) pump current when we included glutaredoxin 1 in patch pipette solutions to reverse glutathionylation. We conclude that transient K(+)-induced peak Na(+)-K(+) pump current reflects the effect

  16. NMR studies of the fifth transmembrane segment of Na+,K+-ATPase reveals a non-helical ion-binding region

    DEFF Research Database (Denmark)

    Underhaug, Jarl; Jakobsen, Louise Odgaard; Esmann, Mikael

    2006-01-01

    The structure of a synthetic peptide corresponding to the fifth membrane-spanning segment (M5) in Na(+),K(+)-ATPase in sodium dodecyl sulfate (SDS) micelles was determined using liquid-state nuclear magnetic resonance (NMR) spectroscopy. The spectra reveal that this peptide is substantially less...... transmembrane element of the Ca(2+)-ATPase. Furthermore, this region spans the residues implicated in Na(+) and K(+) transport, where they are likely to offer the flexibility needed to coordinate Na(+) as well as K(+) during active transport....... alpha-helical than the corresponding M5 peptide of Ca(2+)-ATPase. A well-defined alpha-helix is shown in the C-terminal half of the peptide. Apart from a short helical stretch at the N-terminus, the N-terminal half contains a non-helical region with two proline residues and sequence similarity to a non-structured...

  17. Spectral Analysis Method of Plastic Scintillator-based Radiation Detector against Nuclear/Radiological Terrorism

    International Nuclear Information System (INIS)

    Kwak, Sung-Woo; Yoo, Ho-Sik; Jang, Sung Soon; Kim, Jung-Soo; Yoon, Wan-Ki

    2008-01-01

    In these days, the threats relating to nuclear or radioactive materials have become a matter of internationally increased grave concern. A plastic scintillation detector in radiation portal monitoring (RPM) application has been used to detect radioactive sources in steel scrap entering reprocessing facilities, and to detect illicit transport of radioactive material across border ports-of-entry. The detection systems for RPM application usually are large and can not easily be moved to a different location. For some situations, an inconspicuous and mobile system for the radioactive or nuclear material during road transport is needed. The mobile radiation detection system has employed a NaI- based radiation detector to detect and identify the material hidden in vehicle. There are some operational constraints - short measuring time, weak activity due to heavy shield of illegal source, long distance - of inspection system in such nuclear security applications. Due to these constraints, large area sensor is required to maximize its sensitivity. Large NaI material, however, is extremely expensive. In designing a radiation detector for prevention of illicit trafficking of nuclear or radioactive materials, the trade-off should be carefully optimized between performance and cost in order to achieve cost-effective inspection system. For the cost-effective mobile radiation detection system, this paper describes new spectral analysis method to use the crude spectroscopic information available from a plastic detector to discriminate other man-made radiation source from NORM

  18. Nuclear energy between science and public

    Energy Technology Data Exchange (ETDEWEB)

    Bobnar, B [Inst. Jozef Stefan, Ljubljana (Slovenia)

    1992-07-01

    The objective of the presented research was to establish the presence and the structure of nuclear energy as a theme in Slovenian mass media and at the same time to answer the question what chances an active Slovenian reader had in the year 1991 to either strengthen or change his opinion on nuclear power. Measurement and analysis of chosen relevant variables in 252 contributions in six Slovenian mass media publications in the year 1991 showed that the most frequent nuclear theme was decommissioning and closing down of a nuclear power plant. Other themes followed in the order of the frequency of appearance: nuclear energy as an economic issue, waste disposal, NPP Krsko operation, influence on health, information about events, seismic questions. The scientific theme - nuclear energy, was intensely represented in chosen Slovenian mass media publications in 1991. Common to all nuclear themes is that they were being presented from the political point of view. (author) [Slovenian] Prispevek s strani komunikoloskih raziskav osvetljuje nekatere dileme ob vstopanju stroke v svet mnozicnih medijev. Cilj raziskave je bil: ugotoviti prisotnost in strukturo jedrske energije kot teme v javnih pisnih medijih v letu 1991 ter oceniti, ali je imel povprecni bralec vsaj enega dnevnega casopisa moznost, da okrepi ali spremeni svoje mnenje o jedrski energiji. Merjenje in analiza relevantnih izbranih spremenljivk v 252 prispevkih v sestih slovenskih pisnih medijih sta pokazala, da je bila najpogostejsa jedrska tema zapiranje in razgradnja jedrskih elektrarn, sledili so ekonomski vidiki jedrske energije, vprasanja, povezana s skladiscenjem in odlagaliscem radioaktivnih odpadkov, delovanje NE Krsko, vpliv jedrske energije na zdravje, informacije o nezgodah, seizmoloska vprasanja. Strokovna tema - jedrska energija, je bila intenzivno predstavljena v slovenskih pisnih medijih v letu 1991, vendar prevladujoce s politicnega zornega kota. (author)

  19. Crystal structure of a Na+-bound Na+,K+-ATPase preceding the E1P state.

    Science.gov (United States)

    Kanai, Ryuta; Ogawa, Haruo; Vilsen, Bente; Cornelius, Flemming; Toyoshima, Chikashi

    2013-10-10

    Na(+),K(+)-ATPase pumps three Na(+) ions out of cells in exchange for two K(+) taken up from the extracellular medium per ATP molecule hydrolysed, thereby establishing Na(+) and K(+) gradients across the membrane in all animal cells. These ion gradients are used in many fundamental processes, notably excitation of nerve cells. Here we describe 2.8 Å-resolution crystal structures of this ATPase from pig kidney with bound Na(+), ADP and aluminium fluoride, a stable phosphate analogue, with and without oligomycin that promotes Na(+) occlusion. These crystal structures represent a transition state preceding the phosphorylated intermediate (E1P) in which three Na(+) ions are occluded. Details of the Na(+)-binding sites show how this ATPase functions as a Na(+)-specific pump, rejecting K(+) and Ca(2+), even though its affinity for Na(+) is low (millimolar dissociation constant). A mechanism for sequential, cooperative Na(+) binding can now be formulated in atomic detail.

  20. Na+-H+ exchange and Na+-dependent transport systems in streptozotocin diabetic rat kidneys

    International Nuclear Information System (INIS)

    El-Seifi, S.; Freiberg, J.M.; Kinsella, F.J.; Cheng, L.; Sacktor, B.

    1987-01-01

    The streptozotocin-induced diabetic rat was used to test the hypothesis that Na + -H + exchange activity in the proximal tubule luminal membrane would be increased in association with renal hypertrophy, altered glomerular hemodynamics, enhanced filtered load and tubular reabsorption of 22 Na + , and stimulated 22 Na= pump activity in the basolateral membrane, previously reported characteristics of this experimental animal model. Amiloride-sensitive H + gradient-dependent Na + uptake and Na + gradient-dependent H + flux were increased in brush-border membrane vesicles from the streptozotocin-treated animals. Na + gradient-dependent uptakes of phosphate, D-glucose, L-proline, and myoinositol were decreased in the drug-induced diabetic animals. These membrane transport alterations were not found when the streptozotocin-diabetic animals were treated with insulin

  1. The falsification of Chiral Nuclear Forces

    Science.gov (United States)

    Ruiz Arriola, E.; Amaro, J. E.; Navarro Perez, R.

    2017-03-01

    Predictive power in theoretical nuclear physics has been a major concern in the study of nuclear structure and reactions. The Effective Field Theory (EFT) based on chiral expansions provides a model independent hierarchy for many body forces at long distances but their predictive power may be undermined by the regularization scheme dependence induced by the counterterms and encoding the short distances dynamics which seem to dominate the uncertainties. We analyze several examples including zero energy NN scattering or perturbative counterterm-free peripheral scattering where one would expect these methods to work best and unveil relevant systematic discrepancies when a fair comparison to the Granada-2013 NN-database and partial wave analysis (PWA) is undertaken. Work supported by Spanish Ministerio de Economia y Competitividad and European FEDER funds (grant FIS2014-59386-P), the Agencia de Innovacion y Desarrollo de Andalucia (grant No. FQM225), the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract No. DE-AC52-07NA27344, U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Award No. DE-SC0008511 (NUCLEI SciDAC Collaboration)

  2. Studies in Low-Energy Nuclear Science

    International Nuclear Information System (INIS)

    Brune, Carl R.; Grimes, Steven M.

    2010-01-01

    This report presents a summary of research projects in the area of low energy nuclear reactions and structure, carried out between March 1, 2006 and October 31, 2009 which were supported by U.S. DOE grant number DE-FG52-06NA26187. We describe here research into low-energy nuclear reactions and structure. The statistical properties of nuclei have been studied by measuring level densities and also calculating them theoretically. Our approach of measuring level densities via evaporation spectra is able to reach a very wide range of nuclei by using heavy ion beams (we expect to develop experiments using radioactive beams in the near future). Another focus of the program has been on γ-ray strength functions. These clearly impact nuclear reactions, but they are much less understood than corresponding transmission coefficients for nucleons. We have begun investigations of a new approach, using γ-γ coincidences following radiative capture. Finally, we have undertaken several measurements of cross sections involving light nuclei which are important in various applications. The 9 Be(α,n) and B(d,n) reactions have been measured at Ohio University, while neutron-induced reactions have been measured at Los Alamos (LANSCE).

  3. The two C-terminal tyrosines stabilize occluded Na/K pump conformations containing Na or K ions.

    Science.gov (United States)

    Vedovato, Natascia; Gadsby, David C

    2010-07-01

    Interactions of the three transported Na ions with the Na/K pump remain incompletely understood. Na/K pump crystal structures show that the extended C terminus of the Na,K-adenosine triphosphatase (ATPase) alpha subunit directly contacts transmembrane helices. Deletion of the last five residues (KETYY in almost all Na/K pumps) markedly lowered the apparent affinity for Na activation of pump phosphorylation from ATP, a reflection of cytoplasmic Na affinity for forming the occluded E1P(Na3) conformation. ATPase assays further suggested that C-terminal truncations also interfere with low affinity Na interactions, which are attributable to extracellular effects. Because extracellular Na ions traverse part of the membrane's electric field to reach their binding sites in the Na/K pump, their movements generate currents that can be monitored with high resolution. We report here electrical measurements to examine how Na/K pump interactions with extracellular Na ions are influenced by C-terminal truncations. We deleted the last two (YY) or five (KESYY) residues in Xenopus laevis alpha1 Na/K pumps made ouabain resistant by either of two kinds of point mutations and measured their currents as 10-mM ouabain-sensitive currents in Xenopus oocytes after silencing endogenous Xenopus Na/K pumps with 1 microM ouabain. We found the low affinity inhibitory influence of extracellular Na on outward Na/K pump current at negative voltages to be impaired in all of the C-terminally truncated pumps. Correspondingly, voltage jump-induced transient charge movements that reflect pump interactions with extracellular Na ions were strongly shifted to more negative potentials; this signals a several-fold reduction of the apparent affinity for extracellular Na in the truncated pumps. Parallel lowering of Na affinity on both sides of the membrane argues that the C-terminal contacts provide important stabilization of the occluded E1P(Na3) conformation, regardless of the route of Na ion entry into the

  4. The immobilisation of nuclear waste materials containing different alkali elements into single-phase NZP based ceramics

    International Nuclear Information System (INIS)

    Pet'kov, V.I.; Orlova, A.I.; Trubach, I.G.; Demarin, T.; Kurazhkovskaya, V.S.

    2002-01-01

    The NZP matrix, which is based on NaZr 2 (PO 4 ) 3 , is a viable candidate for nuclear waste immobilisation. We examined the possibilities of incorporating of alkali elements into the NZP host structure, investigated the conditions of the crystalline solution formation, and determined the regions of the NZP structure compositional stability for a series of complex orthophosphates of titanium or zirconium and alkali elements A m-x A' x M 2-(m-1)/4 (PO 4 ) 3 with m = 1, 3, or 5 and 0 ≤ x ≤ m, where A and A' are mutually different alkali elements and M is Ti or Zr. The phosphates containing Li-Na, Li-K, Li-Rb, Li-Cs, Na-K, Na-Rb, Na-Cs, K-Rb, K-Cs and Rb-Cs pairs were prepared and studied by X-ray powder analysis, IR spectroscopy, simultaneous DTA-TG measurements and electron microprobe analyses. In the systems studied, wide ranges of crystalline phosphate solutions with tailored alkali metal substitutions were formed owing to the large number of sites available for substitution and high degree of flexibility in the NZP structure. It was found that introduction of the less expensive and lighter Ti in the host phase in place of the commonly used Zr permits cheaper ceramics, having in some cases larger alkali element contents, to be obtained. The phases containing alkali metals can be formed, for instance, during phosphate solidification of molten alkali chlorides with radioactive nuclides from the pyroelectrochemical technologies of nuclear fuel recycling

  5. {sup 18}F-NaF PET/CT: EANM procedure guidelines for bone imaging

    Energy Technology Data Exchange (ETDEWEB)

    Beheshti, M.; Langsteger, W. [St Vincent' s Hospital, PET - CT Center LINZ, Department of Nuclear Medicine and Endocrinology, Linz (Austria); Mottaghy, F.M. [University Hospital Aachen, RWTH Aachen University, Department of Nuclear Medicine, Aachen (Germany); Maastricht University Medical Center, Department of Nuclear Medicine, Maastricht (Netherlands); Payche, F. [Louis Mourier Hospital, Department of Nuclear Medicine, Colombes (France); Behrendt, F.F.F. [University Hospital Aachen, RWTH Aachen University, Department of Nuclear Medicine, Aachen (Germany); Wyngaert, T.V. den [Antwerp University Hospital, Department of Nuclear Medicine, Edegem (Belgium); Fogelman, I. [King' s College, Department of Nuclear Medicine, London (United Kingdom); Strobel, K. [Lucerne Cantonal Hospital, Department of Radiology and Nuclear Medicine, Lucerne (Switzerland); Celli, M.; Fanti, S. [Policlinico S. Orsola-Malpighi, Department of Nuclear Medicine, PET Unit, Bologna (Italy); Giammarile, F. [Centre Hospitalier Universitaire de Lyon, Department of Nuclear Medicine, Lyon (France); Krause, B. [University Hospital Rostock, Department of Nuclear Medicine, Rostock (Germany)

    2015-10-15

    The aim of this guideline is to provide minimum standards for the performance and interpretation of {sup 18}F-NaF PET/CT scans. Standard acquisition and interpretation of nuclear imaging modalities will help to provide consistent data acquisition and numeric values between different platforms and institutes and to promote the use of PET/CT modality as an established diagnostic modality in routine clinical practice. This will also improve the value of scientific work and its contribution to evidence-based medicine. (orig.)

  6. Improvement of Sodium Neutronic Nuclear Data for the Computation of Generation IV Reactors

    International Nuclear Information System (INIS)

    Archier, P.

    2011-01-01

    The safety criteria to be met for Generation IV sodium fast reactors (SFR) require reduced and mastered uncertainties on neutronic quantities of interest. Part of these uncertainties come from nuclear data and, in the particular case of SFR, from sodium nuclear data, which show significant differences between available international libraries (JEFF-3.1.1, ENDF/B-VII.0, JENDL-4.0). The objective of this work is to improve the knowledge on sodium nuclear data for a better calculation of SFR neutronic parameters and reliable associated uncertainties. After an overview of existing 23 Na data, the impact of the differences is quantified, particularly on sodium void reactivity effects, with both deterministic and stochastic neutronic codes. Results show that it is necessary to completely re-evaluate sodium nuclear data. Several developments have been made in the evaluation code Conrad, to integrate new nuclear reactions models and their associated parameters and to perform adjustments with integral measurements. Following these developments, the analysis of differential data and the experimental uncertainties propagation have been performed with Conrad. The resolved resonances range has been extended up to 2 MeV and the continuum range begins directly beyond this energy. A new 23 Na evaluation and the associated multigroup covariances matrices were generated for future uncertainties calculations. The last part of this work focuses on the sodium void integral data feedback, using methods of integral data assimilation to reduce the uncertainties on sodium cross sections. This work ends with uncertainty calculations for industrial-like SFR, which show an improved prediction of their neutronic parameters with the new evaluation. (author) [fr

  7. Anion-coupled Na efflux mediated by the human red blood cell Na/K pump

    International Nuclear Information System (INIS)

    Dissing, S.; Hoffman, J.F.

    1990-01-01

    The red cell Na/K pump is known to continue to extrude Na when both Na and K are removed from the external medium. Because this ouabain-sensitive flux occurs in the absence of an exchangeable cation, it is referred to as uncoupled Na efflux. This flux is also known to be inhibited by 5 mM Nao but to a lesser extent than that inhibitable by ouabain. Uncoupled Na efflux via the Na/K pump therefore can be divided into a Nao-sensitive and Nao-insensitive component. We used DIDS-treated, SO4-equilibrated human red blood cells suspended in HEPES-buffered (pHo 7.4) MgSO4 or (Tris)2SO4, in which we measured 22Na efflux, 35SO4 efflux, and changes in the membrane potential with the fluorescent dye, diS-C3 (5). A principal finding is that uncoupled Na efflux occurs electroneurally, in contrast to the pump's normal electrogenic operation when exchanging Nai for Ko. This electroneutral uncoupled efflux of Na was found to be balanced by an efflux of cellular anions. (We were unable to detect any ouabain-sensitive uptake of protons, measured in an unbuffered medium at pH 7.4 with a Radiometer pH-STAT.) The Nao-sensitive efflux of Nai was found to be 1.95 +/- 0.10 times the Nao-sensitive efflux of (SO4)i, indicating that the stoichiometry of this cotransport is two Na+ per SO4=, accounting for 60-80% of the electroneutral Na efflux. The remainder portion, that is, the ouabain-sensitive Nao-insensitive component, has been identified as PO4-coupled Na transport and is the subject of a separate paper. That uncoupled Na efflux occurs as a cotransport with anions is supported by the result, obtained with resealed ghosts, that when internal and external SO4 was substituted by the impermeant anion, tartrate i,o, the efflux of Na was inhibited 60-80%. This inhibition could be relieved by the inclusion, before DIDS treatment, of 5 mM Cli,o

  8. Nuclear densimeter of soil simulated in MCNP-4C code

    International Nuclear Information System (INIS)

    Braga, Mario R.M.S.S.; Penna, Rodrigo; Vasconcelos, Danilo C.; Pereira, Claubia; Guerra, Bruno T.; Silva, Clemente J.G.C.

    2009-01-01

    The Monte Carlo code (MCNPX) was used to simulate a nuclear densimeter for measuring soil density. An Americium source (E = 60 keV) and a NaI (Tl) detector were placed on soil surface. Results from MCNP shown that scattered photon fluxes may be used to determining soil density. Linear regressions between scattered photons fluxes and soil density were calculated and shown correlation coefficients near unity. (author)

  9. Quistes de los maxilares

    Directory of Open Access Journals (Sweden)

    Ivan Alberto Manotas Arevalo

    2013-12-01

    Full Text Available Los Grandes Quistes de los Maxilares han estado vinculados siempre a la humanidad, desde tiempos remotos, pues han sido halladas en restos de especimenes fosiles, han llamado la atencion de los clínicos, en torno a su etiologia, en la que se ha introducido la participacion de la genetica, (demostrada en el desarrollo de los queratoquistes maxilares, la fisiopatologia, caracteristicas histologicas (inmunohistoquimica, posibilidades diagnosticas por la imagen, (como la tomografia computarizada y la resonancia nuclear magnetica y otras pruebas. Además llaman la atención al estudio, por sus alternativas de manejo especialmente las formas radicales, y el analisis de asociaciones a otras patolo-gias benignas y malignas, y de la recurrencia muy alto de algunas de estas lesiones. Mucho se ha desarrollado para elucidar su naturaleza real, estadificar adecuadamente la lesion descartando asocia-ciones patologicas sindromicas, indicar un tratamiento apropiado, y realizar seguimientos a largo plazo. Este articulo pretende recaudar una information general que de parametros para abordar el estudio de los quistes maxilares a partir de la presentacion de un caso clinico.

  10. Need for capacity building and knowledge management in nuclear applications, an IAEA perspective

    International Nuclear Information System (INIS)

    Rossbach, M.

    2004-01-01

    In view of an aging workforce and an increasing lack of students interested in nuclear technology and sciences many reports have pinpointed to the crucial situation in loosing valuable expertise and urged for the initiation of capable programmes to revitalize training opportunities and public interests in nuclear subjects. Several international and national initiatives emerged to support education and training in nuclear engineering and radiochemistry but it appears that money alone is not sufficient to reverse the trend. Nuclear knowledge management concepts and strategies have been discussed at various levels but a clear picture how to attract more interest in nuclear activities in the young generation did not emerge so far. It seems that only concerted action including social, political, scientific and technical components can positively change public perception of nuclear applications and, hence, result in an increased interest of students to take up this subject and embark in a professional life as a nuclear scientist or engineer. The Department of Nuclear Sciences and Applications (NA) of the IAEA is trying to support - through many different mechanisms - training and education in the nuclear sector and enhance the dissemination of nuclear knowledge from advanced to less advanced countries. Some of the more recent activities of the Department will be described in this communication. (author)

  11. Na5NbO5 and Na5TaO5 phases

    International Nuclear Information System (INIS)

    Darriet, J.; Maazaz, A.; Bouloux, J.C.; Delmas, C.

    1982-01-01

    New ternary oxides of formulas Na 5 NbO 5 and Na 5 TaO 5 have been prepared. They crystallize in the monoclinic system (space group C2/c). The crystal structure of Na 5 NbO 5 has been determined. It derives from a NaCl-type structure by ordering of the cations and of the oxygen vacancies in the anionic sublattice, the corresponding formula being Nasub(5/6)Nbsub(1/6)Osub(5/6)vacant sub(1/6). Sodium and niobium have a distorted square-pyramidal surrounding. (author)

  12. An application of the IAEA GCS-R-3 Standard in Nuclear Quality Management System

    Energy Technology Data Exchange (ETDEWEB)

    Kim, D. I.; Juhn, P. E. [TUEV SUED Korea, Seoul (Korea, Republic of); Kwon, M. J. [TUEV SUED KOCEN, Seoul (Korea, Republic of)

    2012-03-15

    IAEA GCS-R-3 Standard (2006) is intended to help nuclear community establishing a nuclear quality management system that integrates such 6 elements as safety, health, environment, security, quality and economics. In the present paper, the management principles of GCS-R-3 Standard are compared with those of ISO 9001 and ASME N/A-1 Codes and Standards. The paper also summarizes the worldwide survey on application of GS-R-3, which was conducted by the TUEV SUED Korea in 2011. The result concludes that the top priority should be given to safety upon which the management system must be based, in proper coordination with other 5 elements to enhance nuclear safety, in particular after Fukushima Dais-Ici nuclear power accidents on 11{sup th} March 2011 in Japan.

  13. Handbook on nuclear data for borehole logging and mineral analysis

    International Nuclear Information System (INIS)

    1993-01-01

    In nuclear geophysics, an extension of the nuclear data available for reactor and shielding calculations, is required. In general, the problems and the methods of attack are the same, but in nuclear geophysics the environment is earth materials, with virtually all the natural elements in the Periodic Table involved, although not at the same time. In addition, the geometrical configurations encountered in nuclear geophysics are very different from those associated with reactor and shielding design, and they can impose a different demand on the required accuracy of the nuclear data and on the dependence on the calculational approach. Borehole logging is a very good example, since an experimental investigation aimed at varying only one parameter (e.g. moisture content) whilst keeping all the others constant in a geologically complex system that effectively exhibits 'infinite geometry' for neutrons and γ rays is virtually impossible. An increasingly important are of nuclear geophysics is the on-line analysis of natural materials such as coal (e.g. C, H, O, Al, Si, Ca, Fe, Cl, S, N,) the raw materials of the cement industry (S, Na, K, Al, Si, Ca, Fe, Mn, Ti, P, Mg, F, O), and mined ores of Fe, Al, Mn, Cu, Ni, Ag and Au, amongst others. Refs, figs and tabs

  14. Synthesis of Na-A and/or Na-X zeolite/porous carbon composites from carbonized rice husk

    International Nuclear Information System (INIS)

    Katsuki, Hiroaki; Komarneni, Sridhar

    2009-01-01

    Na-A and/or Na-X zeolite/porous carbon composites were prepared under hydrothermal conditions by NaOH dissolution of silica first from carbonized rice husk followed by addition of NaAlO 2 and in situ crystallization of zeolites i.e., using a two-step process. When a one-step process was used, both Na-A and Na-X zeolites crystallized on the surface of carbon. Na-A or Na-X zeolite crystals were prepared on the porous carbonized rice husk at 90 deg. C for 2-6 h by changing the SiO 2 /Al 2 O 3 , H 2 O/Na 2 O and Na 2 O/SiO 2 molar ratios of precursors in the two-step process. The surface area and NH 4 + -cation exchange capacity (CEC) of Na-A zeolite/porous carbon were found to be 171 m 2 /g and 506 meq/100 g, respectively, while those of Na-X zeolite/porous carbon composites were 676 m 2 /g and 317 meq/100 g, respectively. Na-A and Na-X zeolites are well-known microporous and hydrophilic materials while carbonized rice husk was found to be mesoporous (pores of ∼3.9 nm) and hydrophobic. These hybrid microporous-mesoporous and hydrophilic-hydrophobic composites are expected to be useful for decontamination of metal cations as well as organic contaminants simultaneously. - Graphical Abstract: Novel Na-X zeolite/porous carbon composite.

  15. Equilibrium chemical transformations in NaPO3 + NaCl melts

    International Nuclear Information System (INIS)

    Kovarskaya, E.N.; Rodionov, Yu.I.

    1988-01-01

    Because of the problems of the burial of solidified radioactive wastes into different geological rock formations, in particular into massives of rock-salt, the state of molten polyphosphate-chloride mixtures (taking into account the chemical character of the interaction of their components) for a prolonged period of time. The equilibrium products of the reaction in the NaPO 3 -NaCl system were studied in melts in air in the composition range of 30-70 mole % NaCl. It was shown that with increase in the NaCl content in the mixtures, the polyphosphate gradually depolymerizes to sodium tri-, di-, and monophosphates, and the composition of the equilibrium melts is dependent only on the ratio between the components in the initial molten mixtures. The time until the equilibrium is attained is shorter, the higher is the experimental temperature

  16. Interaction between Na+/K+-pump and Na+/Ca2+-exchanger modulates intercellular communication.

    Science.gov (United States)

    Matchkov, Vladimir V; Gustafsson, Helena; Rahman, Awahan; Briggs Boedtkjer, Donna M; Gorintin, Sarah; Hansen, Anne Kirstine; Bouzinova, Elena V; Praetorius, Helle A; Aalkjaer, Christian; Nilsson, Holger

    2007-04-13

    Ouabain, a specific inhibitor of the Na(+)/K(+)-pump, has previously been shown to interfere with intercellular communication. Here we test the hypothesis that the communication between vascular smooth muscle cells is regulated through an interaction between the Na(+)/K(+)-pump and the Na(+)/Ca(2+)-exchanger leading to an increase in the intracellular calcium concentration ([Ca(2+)](i)) in discrete areas near the plasma membrane. [Ca(2+)](i) in smooth muscle cells was imaged in cultured rat aortic smooth muscle cell pairs (A7r5) and in rat mesenteric small artery segments simultaneously with force. In A7r5 coupling between cells was estimated by measuring membrane capacitance. Smooth muscle cells were uncoupled when the Na(+)/K(+)-pump was inhibited either by a low concentration of ouabain, which also caused a localized increase of [Ca(2+)](i) near the membrane, or by ATP depletion. Reduction of Na(+)/K(+)-pump activity by removal of extracellular potassium ([K(+)](o)) also uncoupled cells, but only after inhibition of K(ATP) channels. Inhibition of the Na(+)/Ca(2+)-exchange activity by SEA0400 or by a reduction of the equilibrium potential (making it more negative) also uncoupled the cells. Depletion of intracellular Na(+) and clamping of [Ca(2+)](i) at low concentrations prevented the uncoupling. The experiments suggest that the Na(+)/K(+)-pump may affect gap junction conductivity via localized changes in [Ca(2+)](i) through modulation of Na(+)/Ca(2+)-exchanger activity.

  17. Intracellular Na(+) and metabolic modulation of Na/K pump and excitability in the rat suprachiasmatic nucleus neurons.

    Science.gov (United States)

    Wang, Yi-Chi; Yang, Jyh-Jeen; Huang, Rong-Chi

    2012-10-01

    Na/K pump activity and metabolic rate are both higher during the day in the suprachiasmatic nucleus (SCN) that houses the circadian clock. Here we investigated the role of intracellular Na(+) and energy metabolism in regulating Na/K pump activity and neuronal excitability. Removal of extracellular K(+) to block the Na/K pump excited SCN neurons to fire at higher rates and return to normal K(+) to reactivate the pump produced rebound hyperpolarization to inhibit firing. In the presence of tetrodotoxin to block the action potentials, both zero K(+)-induced depolarization and rebound hyperpolarization were blocked by the cardiac glycoside strophanthidin. Ratiometric Na(+) imaging with a Na(+)-sensitive fluorescent dye indicated saturating accumulation of intracellular Na(+) in response to pump blockade with zero K(+). The Na(+) ionophore monensin also induced Na(+) loading and hyperpolarized the membrane potential, with the hyperpolarizing effect of monensin abolished in zero Na(+) or by pump blockade. Conversely, Na(+) depletion with Na(+)-free pipette solution depolarized membrane potential but retained residual Na/K pump activity. Cyanide inhibition of oxidative phosphorylation blocked the Na/K pump to depolarize resting potential and increase spontaneous firing in most cells, and to raise intracellular Na(+) levels in all cells. Nonetheless, the Na/K pump was incompletely blocked by cyanide but completely blocked by iodoacetate to inhibit glycolysis, indicating the involvement of both oxidative phosphorylation and glycolysis in fueling the Na/K pump. Together, the results indicate the importance of intracellular Na(+) and energy metabolism in regulating Na/K pump activity as well as neuronal excitability in the SCN neurons.

  18. Synthesis of zeolites Na-A and Na-X from tablet compressed and calcinated coal fly ash

    Science.gov (United States)

    Hu, Tao; Gao, Wenyan; Liu, Xin; Zhang, Yifu; Meng, Changgong

    2017-10-01

    Zeolites Na-A and Na-X are important synthetic zeolites widely used for separation and adsorption in industry. It is of great significance to develop energy-efficient routines that can synthesize zeolites Na-A and Na-X from low-cost raw materials. Coal fly ash (CFA) is the major residue from the combustion of coal and biomass containing more than 85% SiO2 and Al2O3, which can readily replace the conventionally used sodium silicate and aluminate for zeolite synthesis. We used Na2CO3 to replace the expensive NaOH used for the calcination of CFA and showed that tablet compression can enhance the contact with Na2CO3 for the activation of CFA through calcination for the synthesis of zeolites Na-A and Na-X under mild conditions. We optimized the control variables for zeolite synthesis and showed that phase-pure zeolite Na-A can be synthesized with CFA at reactant molar ratio, hydrothermal reaction temperature and reaction time of 1.3Na2O: 0.6Al2O3: 1SiO2: 38H2O at 80°C for 6 h, respectively, while phase-pure zeolite Na-X can be synthesized at 2.2Na2O: 0.2Al2O3: 1SiO2: 88H2O at 100°C for 8 h, respectively. The composition, morphology, specific surface area, vibration spectrum and thermogravimetry of synthesized Na-A and Na-X were further characterized.

  19. Break-up of Ca-montmorillonite particles by Na-montmorillonite

    International Nuclear Information System (INIS)

    Hedstroem, Magnus; Birgersson, Martin

    2012-01-01

    Document available in extended abstract form only. In the Swedish KBS-3 concept for a geological deep storage of spent nuclear fuel, bentonite of high montmorillonite content is proposed to serve as a buffer surrounding copper canisters containing the spent fuel. Montmorillonite has an exceptional affinity for water which results in the build-up of a swelling pressure when bentonite is placed in a confined volume. However, there is a concern that during and after a glaciation, meltwater of low ionic strength may cause the bentonite to swell extensively into fractures and turn into a sol that could be transported away by the seeping water. It is thus warranted to understand the behaviour of montmorillonite at aqueous condition of low ionic strength. Turbidity measurements were used to a large extent in previous work to follow the free swelling or settling process of montmorillonite in various aqueous solutions and thereby give information regarding sol formation. From theory we know that turbidity of a suspension is proportional to the particle concentration. However turbidity is also proportional to V p 2 where V p is the volume of the scattering particle. Thus the fact that turbidity of a Ca-montmorillonite suspension is higher than the turbidity of a Na- montmorillonite suspension of the same clay concentration indicates that Na-montmorillonite separate into smaller particles than Ca-montmorillonite. In this work we make use this size dependence to quantify the difference between Wyoming, Milos and Kutch montmorillonite in particular with respect to how mixed Ca/Na montmorillonite systems behave. Some Ca/Mg, Mg/Na and Na/K systems are also included for comparison. Figure 1 shows the final (stabilized) turbidity response of mixed Wy-Ca/Na montmorillonite as a function of the fraction of Ca 2+ in the clay. Starting material are suspensions of homo-ionic Wy-Ca and Wy-Na montmorillonite at a concentration of 1 g/l. The turbidity of the suspensions of the homo

  20. Estimation of radioactive effluents concentrations in the vicinity of nuclear power plant; Predviduvanje na koncentraciite na radioaktivni aerozagaduvaci vo okolinata na nuklearni energetski postrojni

    Energy Technology Data Exchange (ETDEWEB)

    Arsov, Lj [Elektrostopanstvo, Skopje (Yugoslavia)

    1977-07-01

    This paper deals with the problem of mathematical prediction of radioactive effluent concentrations around nuclear power plants. This mathematical model which describes the behaviour of the effluent in the atmosphere here in after is expanded and adapted for radioactive effluent treatment. In this way the mathematical model includes the description of the following effects: the rise of plume caused by its vertical momentum and its heat content, wind velocity profile and vertical growth of the coefficient of diffusion, fallout under gravity, ground deposition, precipitation scavenging, and radioactive decay. The advanced computer program DIFFUS has been applied to evaluate the ground concentration of the nuclides of I, which constitute the greatest risk for population.(author)

  1. Research achievements in Bangladesh agriculture using nuclear techniques

    International Nuclear Information System (INIS)

    Sattar, M.A.

    1997-01-01

    Application of isotope and radiation techniques in Bangladesh agriculture has been initiated in 1961 with the establishment of Atomic Energy Agricultural Research Centre, Dhaka under the then Pakistan Atomic Energy Commission. The activity of the centre was strengthened and upgraded to the level of an institute as a constituent organization of Bangladesh Atomic Energy Commission in 1972. It was further reorganized, made an autonomous research organization under the Ministry of Agriculture in 1982 and renamed as Bangladesh Institute of Nuclear Agriculture. The other organizations involved in nuclear agricultural research are Institute of Food and Radiation Biology and Bangladesh Agricultural University. A number of technologies have been developed using nuclear techniques that imparted on agricultural development. Sixteen new crops were developed using physical (200-700 Gy gamma rays) and chemical mutagen (NaN 3 ). Soil fertility and plant nutrition technologies were developed using both stable and radio isotopes. The improved feeding strategies and utilization of locally available low quality feed material (rice straw) were determined using 51 Cr-EDTA and 125 I in order to have better livestock growth and reproduction ability. Several constraints related to nuclear research were identified. Increased government commitment and international cooperation are of the utmost importance for effective utilization of the benefits of nuclear technology and to face the increasing demand for food for the ever increasing population in years to come

  2. Effluent monitoring for nuclear safeguards

    International Nuclear Information System (INIS)

    Stanchi, L.

    1977-01-01

    A microprocessor-based instrument operates a continuous surveillance on effluents from a nuclear facility. It receives and evaluates pulses from two NaI detectors and a set of single-channel analyzers. It has self-diagnosing capability so that it takes actions not only when it recognizes excessive radioactivity but also when it ascertains some abnormal behavior. Power failure procedure and automatic restart are provided. Operative constants such as alarm thresholds, times, and number of successive measurements are permanently stored in a read/write battery operated C-MOS memory. The program allows automatic succession of phases in a peculiar way and has a feature for loading an auxiliary program into RAMs

  3. Effluent monitoring for nuclear safeguards

    International Nuclear Information System (INIS)

    Stanchi, L.

    1976-01-01

    A microprocessor-based instrument operates a continuous surveillance on effluents from a nuclear facility. It receives and evaluates pulses from two NaI detectors and a set of single-channel analyzers. It has self-diagnosing capability so that it takes actions not only when it recognizes excessive radioactivity but also when it ascertains some abnormal behavior. Power failure procedure and automatic restart are provided. Operative constants such as alarm thresholds, times, and number of successive measurements are permanently stored in a read/write battery operated C-MOS memory. The program allows automatic succession of phases in a peculiar way and has a feature for loading an auxiliary program into RAMs

  4. Comparison of nuclear reactor types of the next generation; Komparativni prikaz novih tipova reaktorskih komercijalnih postrojenja slijedece generacije

    Energy Technology Data Exchange (ETDEWEB)

    Pavlovic, Z; Kastelan, M [NPP Krsko (Slovenia)

    1992-07-01

    The paper presents a comparison for a selected relevant set of parameters for different commercial nuclear reactor types at the next generation. This parameters overview could serve as the base for the semi-quantitative decision bases for the selection of the future nuclear strategy. The number of advanced reactor designs of the LWR, HWR, GCR and LMR type are presented. Even currently many of them are still on the drawing boards, the concepts and designs should be assessed in the sense of sensible approach for planning the possible future nuclear strategy. (author) Clanek predstavlja usporedbu odabranih bitnih parametara karakteristicnih za razlicite tipove energetskih nuklearnih postrojenja slijedece generacije. Prikazani pregled parametara omogucava osnov za polu kvantitativnu osnovu za odlucivanje u svrhu donosenja odluke oko odrednica buduce strategije uporabe nuklearne energije. Brojni koncepti naprednih nuklearnih reaktora tipa LWR, HWR, GCR i LMR su prezentirani. S obzirom na cinjenicu da se mnogi of prezentiranih nalaze jos uvijek na crtacim daskama projektanata, koncepti i projekti koji su iz njih proizasli zahtijevaju analizu u smislu kvalitativnog pristupa planiranja moguce buduce nuklearne startegije. (author)

  5. The rapid-onset dystonia parkinsonism mutation D923N of the Na+, K+-ATPase alpha3 isoform disrupts Na+ interaction at the third Na+ site.

    Science.gov (United States)

    Einholm, Anja Pernille; Toustrup-Jensen, Mads S; Holm, Rikke; Andersen, Jens Peter; Vilsen, Bente

    2010-08-20

    Rapid-onset dystonia parkinsonism (RDP), a rare neurological disorder, is caused by mutation of the neuron-specific alpha3-isoform of Na(+), K(+)-ATPase. Here, we present the functional consequences of RDP mutation D923N. Relative to the wild type, the mutant exhibits a remarkable approximately 200-fold reduction of Na(+) affinity for activation of phosphorylation from ATP, reflecting a defective interaction of the E(1) form with intracellular Na(+). This is the largest effect on Na(+) affinity reported so far for any Na(+), K(+)-ATPase mutant. D923N also affects the interaction with extracellular Na(+) normally driving the E(1)P to E(2)P conformational transition backward. However, no impairment of K(+) binding was observed for D923N, leading to the conclusion that Asp(923) is specifically associated with the third Na(+) site that is selective toward Na(+). The crystal structure of the Na(+), K(+)-ATPase in E(2) form shows that Asp(923) is located in the cytoplasmic half of transmembrane helix M8 inside a putative transport channel, which is lined by residues from the transmembrane helices M5, M7, M8, and M10 and capped by the C terminus, recently found involved in recognition of the third Na(+) ion. Structural modeling of the E(1) form of Na(+), K(+)-ATPase based on the Ca(2+)-ATPase crystal structure is consistent with the hypothesis that Asp(923) contributes to a site binding the third Na(+) ion. These results in conjunction with our previous findings with other RDP mutants suggest that a selective defect in the handling of Na(+) may be a general feature of the RDP disorder.

  6. Recikliranje plastenk na kreativen način

    OpenAIRE

    Pavlin, Suzana

    2017-01-01

    Plastenke, poleg ostalih plastičnih izdelkov, v zadnjih letih predstavljajo pravo katastrofo za okolje. Domnevamo, da se le redko kdo vpraša, kaj se zgodi z njo po tem, ko je iz nje zaužil še zadnjo kapljico vode. Plastenka je lahko kot večina ostalih komunalnih odpadkov ponovno uporabljena, reciklirana, sežgana ali odložena na deponijo. V primeru nespoštovanja Zakona o varstvu okolja pa pristane v naravi, pogosto v morju, kjer prav počasi razpada in negativno vpliva na celoten ekosistem. V d...

  7. Plant Defensins NaD1 and NaD2 Induce Different Stress Response Pathways in Fungi

    Directory of Open Access Journals (Sweden)

    Peter M. Dracatos

    2016-09-01

    Full Text Available Nicotiana alata defensins 1 and 2 (NaD1 and NaD2 are plant defensins from the ornamental tobacco that have antifungal activity against a variety of fungal pathogens. Some plant defensins interact with fungal cell wall O-glycosylated proteins. Therefore, we investigated if this was the case for NaD1 and NaD2, by assessing the sensitivity of the three Aspergillus nidulans (An O-mannosyltransferase (pmt knockout (KO mutants (An∆pmtA, An∆pmtB, and An∆pmtC. An∆pmtA was resistant to both defensins, while An∆pmtC was resistant to NaD2 only, suggesting NaD1 and NaD2 are unlikely to have a general interaction with O-linked side chains. Further evidence of this difference in the antifungal mechanism was provided by the dissimilarity of the NaD1 and NaD2 sensitivities of the Fusarium oxysporum f. sp. lycopersici (Fol signalling knockout mutants from the cell wall integrity (CWI and high osmolarity glycerol (HOG mitogen-activated protein kinase (MAPK pathways. HOG pathway mutants were sensitive to both NaD1 and NaD2, while CWI pathway mutants only displayed sensitivity to NaD2.

  8. Experimental study of the {sup 22}Ne(p,{gamma}){sup 23}Na reaction and its implications for novae scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Menzel, Marie-Luise

    2013-08-01

    The {sup 22}Ne(p,{gamma}){sup 23}Na reaction belongs to the catalytic neon-sodium cycle and has an important role in the explosive hydrogen burning. The neon-sodium cycle takes place at temperatures of T = 0.1 - 0.5 GK and is assumed to occur in different astrophysical systems: e.g. in novae, in super novae of type Ia and during the shell-burning of red giant branch stars. The implications of {sup 22}Ne(p,{gamma}){sup 23}Na and the neon-sodium cycle in a nova scenario have been studied by using the nuclear network code libnucnet at GSI in Darmstadt. A nova is an outburst of matter in a binary system consisting of a white dwarf and a red giant star. It is therefore a representative phenomenon for explosive hydrogen burning. For the calculation of the nucleosynthesis during the nova outburst, the code libnucnet requires the initial mass composition of the novae partners, the temperature and density profiles of the nova explosion and the thermonuclear reaction rates of the participating reactions. In the following, the code determined the flow and the final atomic abundance in the neon-sodium cycle during the entire nova process. Additionally, the influence of the temperature profile of the novae outburst as well as the thermonuclear reaction rate of the {sup 22}Ne(p,{gamma}){sup 23}Na reaction on the final atomic abundance in the outburst has been studied. A characteristic measure for the reactions in astrophysical environments is the thermonuclear reaction rate. The reaction rate of {sup 22}Ne(p,{gamma}){sup 23}Na has still strong uncertainties in the temperature range of T = 0.03 - 0.3 GK. These uncertainties are based on insufficient upper limits of the resonance strengths as well as the possible existence of tentative states that are populated in the energy range of E{sup lab}{sub p} = 30 - 300 keV. The research presented in this thesis is dedicated to the experimental study of the {sup 22}Ne(p,{gamma}){sup 23}Na reaction for an improved determination of the

  9. Glutamate Water Gates in the Ion Binding Pocket of Na(+) Bound Na(+), K(+)-ATPase

    DEFF Research Database (Denmark)

    Han, Minwoo; Kopec, Wojciech; Solov'yov, Ilia A

    2017-01-01

    III is always protonated. Glutamic acid residues in the three binding sites act as water gates, and their deprotonation triggers water entry to the binding sites. From DFT calculations of Na(+) binding energies, we conclude that three protons in the binding site are needed to effectively bind Na......The dynamically changing protonation states of the six acidic amino acid residues in the ion binding pocket of the Na(+), K(+) -ATPase (NKA) during the ion transport cycle are proposed to drive ion binding, release and possibly determine Na(+) or K(+) selectivity. We use molecular dynamics (MD......(+) from water and four are needed to release them in the next step. Protonation of Asp926 in site III will induce Na(+) release, and Glu327, Glu954 and Glu779 are all likely to be protonated in the Na(+) bound occluded conformation. Our data provides key insights into the role of protons in the Na...

  10. Adaptability of Brayton cycle conversion systems to fast, epithermal and thermal spectrum space nuclear reactors

    International Nuclear Information System (INIS)

    Tilliette, Z.P.

    1988-01-01

    The two French Government Agencies C.N.E.S. (Centre National d'Etudes Spatiales) and C.E.A. (Commissariat a l'Energie Atomique) are carrying out joint preliminary studies on space nuclear power systems for future ARIANE 5 launch vehicle applications. The Brayton cycle is the reference conversion system, whether the heat source is a liquid metal-cooled (NaK, Na or Li) reactor or a gas-cooled direct cycle concept. The search for an adequate utilization of this energy conversion means has prompted additional evaluations featuring the definition of satisfactory cycle conditions for these various kinds of reactor concepts. In addition to firstly studied fast and epithermal spectrum ones, thermal spectrum reactors can offer an opportunity of bringing out some distinctive features of the Brayton cycle, in particular for the temperature conditioning of the efficient metal hydrides (ZrH, Li/sub 7/H) moderators. One of the purposes of the paper is to confirm the potential of long lifetime ZrH moderated reactors associated with a gas cycle and to assess the thermodynamical consequences for both Nak(Na)-cooled or gas-cooled nuclear heat sources. This investigation is complemented by the definition of appropriate reactor arrangements which could be presented on a further occasion

  11. Nuclear energy in the former Soviet Union. From secrecy to export product; Kernenergie in de voormalige Sovjet-Unie. Van geheimhouding tot exportproduct

    Energy Technology Data Exchange (ETDEWEB)

    Tellegen, E. [Departement Innovatie- en Milieuwetenschappen, Universiteit Utrecht, Utrecht (Netherlands)

    2006-07-01

    In this special issue of the magazine attention is paid to several aspects of nuclear energy. In this article the role of nuclear energy in the former Soviet Union is discussed with special attention to the Chernobyl accident on April 26, 1986. [Dutch] In vergelijking met landen als de Verenigde Staten en Engeland verliep de ontwikkeling van nucleaire energie in de Sovjet-Unie in een traag tempo. Het totalitaire karakter van de Sovjet-maatschappij werkte bovendien een lichtzinnige toepassing in de hand. Na de ramp in Tsjenobyl stagneerde de ontwikkeling, niet zozeer door de ramp als wel door de economische terugval na het uiteenvallen van de Unie. Deze terugval was echter van tijdelijke aard.

  12. Influência das gonadotrofinas na regulação da maturação nuclear de oócitos eqüinos Influence of gonadotropins on nuclear maturation of equine oocytes

    Directory of Open Access Journals (Sweden)

    Juan Manuel Larre Borges

    1998-06-01

    Full Text Available A maturação in vitro, fecundação e as técnicas de cultivo de embriões na espécie eqüina são extremamente importantes e necessárias para se examinar as causas de repetição de cio, redução de concepção em éguas velhas e também para a preservação da espécie eqüina. Para avaliar o efeito das gonadotrofinas na regulação da maturação nuclear de oócitos eqüinos, folículos com diâmetro entre 5 a 20mm foram aspirados de 551 ovários provenientes de matadouro obtendo-se 408 oócitos aptos para cultivo. Após a aspiração, os oócitos foram avaliados no próprio líquido folicular quanto a sua integridade e distribuídos nos diferentes tratamentos. No Tratamento I (T1 - grupo controle - os oócitos (n=92 foram cultivados em TCM-199 modificado (mod., com 25mM de HEPES, 2,2mg/ml de bicarbonato de sódio, 1 mi g/ml 17-beta estradiol, 250mi M de piruvato de sódio e 0,4% de albumina sérica bovina. No tratamento 2 (T2, os oócitos (n= 108 foram cultivados no mesmo meio TC M-199 mod. acrescido de lug/ml de hormônio luteinizante suíno (LHs. No Tratamento 3 (T3, os oócitos (n=102 também foram cultivados em TCM-199 mod. porém com 0,5mi g/ml de hormônio folículo estimulante suíno (FSHs e no Tratamento 4 (T4 os oócitos (n= 106 foram cultivados com 1mi g/ml de LHs e 0,5mi g/ml, de FSHs. Os oócitos dos quatros tratamentos foram cultivados em estufa a 39°C com 5% de CO2 , e 95% de umidade relativa no ar, durante 24 h. Após este período, as células do Cumulus oophorus foram removidas e os oócitos fixados em solução de ácido acético glacial-metanol (1:3 em placas de Petri 10 x 35mm por 24h sendo posteriormente corados com aceto-orceína. O percentual de oócitos em telófase I / metáfase II foi de 55,6% (59/106 para o T4 (FSHs/LHs e de 53,9% (55/102 para o T3 (FSHs, os quais não diferiram significativamente. No entanto, estes percentuais foram significativamente superiores (pIn vitro maturation, in vitro fertilization

  13. Securing a better future for all: Nuclear techniques for global development and environmental protection. NA factsheet on nuclear and atomic data: Providing values for science

    International Nuclear Information System (INIS)

    2012-01-01

    The IAEA supports nuclear research activities in Member States by providing essential nuclear data and serving as the central agency for the collection and dissemination of data from laboratories worldwide. The EXFOR database contains a compilation of experimental reaction data from all around the world, and this effort - led by the IAEA - has been very well received, as it provides invaluable data for nuclear calculations and evaluations to researchers in Member States. ENSDF is a collection of evaluated data on the structure and decay properties of radioactive nuclides collected worldwide through a network coordinated by the IAEA. The IAEA has also developed tools to allow users to visualize data, since visual presentation of data in the form of a plot makes them easier to understand and appreciate. Two important applications are available from the Nuclear Data Services web site: LiveChart interactively presents nuclide properties, and ZVView plots reaction cross-sections, both from evaluated files and from EXFOR, as 2-D or 3-D plots. Concerted efforts by the IAEA include coordination of activities in Member States, such as EXFOR and ENSDF, coordinated research project (CRP) implementation, and also staff efforts, which have resulted in data libraries of immense value. IBANDL and RIPL-3 are examples of two databases resulting from CRPs. IBANDL is a database of experimental and evaluated nuclear cross-sections relevant to ion beam analysis. RIPL-3 is a library of reference input parameters which are essential ingredients of theoretical modelling codes. By providing a complete set of verified parameters, it is ensured that evaluations carried out around the world are compatible and can be produced easily and efficiently.

  14. The structure of phosphate glass biomaterials from neutron diffraction and 31P nuclear magnetic resonance data

    International Nuclear Information System (INIS)

    Pickup, D M; Ahmed, I; Guerry, P; Knowles, J C; Smith, M E; Newport, R J

    2007-01-01

    Neutron diffraction and 31 P nuclear magnetic resonance spectroscopy were used to probe the structure of phosphate glass biomaterials of general composition (CaO) 0.5-x (Na 2 O) x (P 2 O 5 ) 0.5 (x = 0, 0.1 and 0.5). The results suggest that all three glasses have structures based on chains of Q 2 phosphate groups. Clear structural differences are observed between the glasses containing Na 2 O and CaO. The P-O bonds to bridging and non-bridging oxygens are less well resolved in the neutron data from the samples containing CaO, suggesting a change in the nature of the bonding as the field strength of the cation increases Na + → Ca 2+ . In the (CaO) 0.5 (P 2 O 5 ) 0.5 glass most of the Ca 2+ ions are present in isolated CaO x polyhedra whereas in the (Na 2 O) 0.5 (P 2 O 5 ) 0.5 glass the NaO x polyhedra share edges leading to a Na-Na correlation. The results of the structural study are related to the properties of the (CaO) 0.4 (Na 2 O) 0.1 (P 2 O 5 ) 0.5 biomaterial

  15. Evaluation of microcomputer assisted system for nuclear emulsion measurement, 2

    International Nuclear Information System (INIS)

    Sato, Yoshihiro; Tezuka, Ikuo; Izawa, Kazuo.

    1983-01-01

    In the reaction of hardrons of several hundreds GeV/c, charm particles with from 10 -12 to 10 -13 second lifetime and beauty particles of shorter lifetime are generated. For directly observing these particles, the experiment using a system which combines nuclear emulsion and an electronic counter is carried out. The authors have engaged in the development of a nuclear emulsion analyzing system since several years ago, and recently developed a program for that system, and made measurement using the program, as one of the works to participate in the NA-19 hybrid experiment of this type, which is a high energy experiment implemented with the CERN accelerator using 350 GeV/c π - beam. In this report, first the outline of NA-19 experiment, next the corresponding of counter coordinates to nuclear emulsions, and the search for candidate events, in which two or more muons exist, that passed iron and tungsten dampers, are described. Further, the measuring programs XPRED 5 and CRS 34 and the relationship between these programs and measuring procedure and the evaluation for them are described at the end. The present program allows the measurement of generated secondary particles without any trouble up to the distance of 5 mm downstream from the collision point. It was also found that the program was applicable to the measurement of the decay phenomena and kink of the particles expected in the measurement of short-life particles. The system capability of estimating the position of target particles within 10 μm greatly contributes to this. (Wakatsuki, Y.)

  16. Dose evaluation on the basis of {sup 24}Na activity in the human body for the criticality accident at JCO Tokai nuclear fuel processing plant

    Energy Technology Data Exchange (ETDEWEB)

    Momose, T.; Tsujimura, N.; Tasaki, T.; Kanai, K.; Hayashi, N.; Shinohara, K. [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

    2000-07-01

    Sodium-24({sup 24}Na) generated in human body due to neutron activation was measured by whole body counter (WBC) in JNC Tokai works. Total 148 persons (JCO employees and contractor, public member, fire fighters, etc.) were measured and {sup 24}Na was detected in the 62 persons. Neutron energy spectrum around the facility was calculated using ANISN and MCNP code and estimated mean capture probability {xi} of neutron for human body at this accident was around 0.25-0.28 at any distance from the center of the precipitation tank. Effective dose equivalent for the 62 persons were estimated based on the calculated conversion factors from {sup 24}Na specific activity to neutron dose. Maximum {sup 24}Na activity was 7.7 kBq (83 Bq({sup 24}Na)/g({sup 23}Na)) in total body and the evaluated effective dose equivalent was 47 mSv. (author)

  17. Fieldable Nuclear Material Identification System

    International Nuclear Information System (INIS)

    Radle, James E.; Archer, Daniel E.; Carter, Robert J.; Mullens, James Allen; Mihalczo, John T.; Britton, Charles L. Jr.; Lind, Randall F.; Wright, Michael C.

    2010-01-01

    The Fieldable Nuclear Material Identification System (FNMIS), funded by the NA-241 Office of Dismantlement and Transparency, provides information to determine the material attributes and identity of heavily shielded nuclear objects. This information will provide future treaty participants with verifiable information required by the treaty regime. The neutron interrogation technology uses a combination of information from induced fission neutron radiation and transmitted neutron imaging information to provide high confidence that the shielded item is consistent with the host's declaration. The combination of material identification information and the shape and configuration of the item are very difficult to spoof. When used at various points in the warhead dismantlement sequence, the information complimented by tags and seals can be used to track subassembly and piece part information as the disassembly occurs. The neutron transmission imaging has been developed during the last seven years and the signature analysis over the last several decades. The FNMIS is the culmination of the effort to put the technology in a usable configuration for potential treaty verification purposes.

  18. NA62 and NA48/2 results on search for Heavy Neutral Leptons

    Directory of Open Access Journals (Sweden)

    Lamanna Gianluca

    2018-01-01

    Full Text Available In this paper we present new results on upper limits for the search of Heavy Neutral Leptons (HNL with data collected by NA48/2 (2003-2004, NA62-RK (2007 and NA62 (2015 CERN experiments. The data collected with different trigger configuration allow to search for both long and short living heavy neutrinos in the mass range below the kaon mass. In addition the status of the search for K+ → π+vv with the NA62 detector will be briefly presented.

  19. Na, Mg, Ni and Cs distribution and speciation after long-term alteration of a simulated nuclear waste glass: A micro-XAS/XRF/XRD and wet chemical study

    Science.gov (United States)

    Curti, Enzo; Dähn, Rainer; Farges, François; Vespa, Marika

    2009-04-01

    Microscopic distribution and speciation of Na, Mg, Ni and Cs in a simulated (inactive) nuclear waste glass were studied using micro X-ray fluorescence (μ-XRF) and micro X-ray absorption spectroscopy (μ-XAS), after aqueous leaching during 12 years at 90 °C. Na and Mg are major constituents of the glass that can be used to determine the progress of the glass corrosion process and the nature of secondary alteration phases. Ni and Cs represent dose determining long-lived radionuclides ( 59Ni, 135Cs) in vitrified nuclear waste. The Na-Mg μ-XRF maps revealed that the core regions of the glass fragments are apparently unaltered and compositionally homogeneous, whereas rims and interstitial spaces are enriched with Mg-rich smectite formed during the leaching process. The micro X-ray absorption near edge structure (μ-XANES) spectra collected at the Mg K-edge in the altered zones show three sharp resonances typical for crystalline Mg-silicates. These resonances are distinctive of Mg occupying undistorted octahedral positions. In contrast, the μ-XANES spectra collected in the core zones of the glass fragments lack this resonance pattern and are identical to the spectra measured on the pristine (unleached) MW glass. Micro extended X-ray absorption fine structure (μ-EXAFS) and μ-XANES analyses at the Ni K-edge revealed three distinct Ni(II) species: (a) Ni uniformly distributed in the glass matrix, (b) micro-inclusions with high Ni concentrations and (c) Ni associated to the Mg-clay. The comparison with reference spectra of unleached MW and other Ni-bearing silicate glasses indicated that species (a) represents the original coordinative environment of Ni in the glass. The μ-EXAFS analyses revealed that species (b) is structural Ni in trevorite (NiFe 2O 4), which probably formed through unmixing processes during the cooling of the glass melt. The μ-EXAFS of species (c) could be successfully modeled assuming specific adsorption or incorporation of Ni into the lattice of

  20. Transmural gradients in Na/K pump activity and [Na+]I in canine ventricle.

    Science.gov (United States)

    Gao, J; Wang, W; Cohen, I S; Mathias, R T

    2005-09-01

    There are well-documented differences in ion channel activity and action potential shape between epicardial (EPI), midmyocardial (MID), and endocardial (ENDO) ventricular myocytes. The purpose of this study was to determine if differences exist in Na/K pump activity. The whole cell patch-clamp was used to measure Na/K pump current (I(P)) and inward background Na(+)-current (I(inb)) in cells isolated from canine left ventricle. All currents were normalized to membrane capacitance. I(P) was measured as the current blocked by a saturating concentration of dihydro-ouabain. [Na(+)](i) was measured using SBFI-AM. I(P)(ENDO) (0.34 +/- 0.04 pA/pF, n = 17) was smaller than I(P)(EPI) (0.68 +/- 0.09 pA/pF, n = 38); the ratio was 0.50 with I(P)(MID) being intermediate (0.53 +/- 0.13 pA/pF, n = 19). The dependence of I(P) on [Na(+)](i) or voltage was essentially identical in EPI and ENDO (half-maximal activation at 9-10 mM [Na(+)](i) or approximately -90 mV). Increasing [K(+)](o) from 5.4 to 15 mM caused both I(P)(ENDO) and I(P)(EPI) to increase, but the ratio remained approximately 0.5. I(inb) in EPI and ENDO were nearly identical ( approximately 0.6 pA/pF). Physiological [Na(+)](i) was lower in EPI (7 +/- 2 mM, n = 31) than ENDO (12 +/- 3 mM, n = 29), with MID being intermediate (9 +/- 3 mM, n = 22). When cells were paced at 2 Hz, [Na(+)](i) increased but the differences persisted (ENDO 14 +/- 3 mM, n = 10; EPI 9 +/- 2 mM, n = 10; and MID intermediate, 11 +/- 2 mM, n = 9). Based on these results, the larger I(P) in EPI appears to reflect a higher maximum turnover rate, which implies either a larger number of active pumps or a higher turnover rate per pump protein. The transmural gradient in [Na(+)](i) means physiological I(P) is approximately uniform across the ventricular wall, whereas transporters that utilize the transmembrane electrochemical gradient for Na(+), such as Na/Ca exchange, have a larger driving force in EPI than ENDO.

  1. Stainless steel phase detector for the 15 UD Pelletron at Nuclear Science Centre

    International Nuclear Information System (INIS)

    Ghosh, S.; Ahuja, R.; Rao, S.; Sarkar, A.; Avasthi, D.K.; Kanjilal, D.; Roy, A.; Bhowmik, R.K.

    1995-01-01

    A spiral resonant cavity has been installed at Nuclear Science Centre to monitor the phase of the accelerated pulsed beam from the 15 UD Pelletron. The cavity, made of stainless steel, is optimised for particles with β 0 similar 0.08. The unloaded Q-factor of the cavity is similar 2000 at a resonant frequency of 48 MHz. The measured sensitivity of the cavity pickup for 161.5 MeV 58 Ni pulsed beam is 5.9 μV (peak to peak) per nA of average beam current. The cavity signal can be used for average beam current down to 1 nA. ((orig.))

  2. Reactions of metal oxides with molten NaPO3 + NaCl mixtures

    International Nuclear Information System (INIS)

    Kovarskaya, E.N.; Mityakhina, V.S.; Rodionov, Yu.I.; Silin, M.Yu.

    1988-01-01

    We consider the dissolution mechanism for iron (III), europium(III), and tin(IV) oxides in molten NaPO 3 + NaCl that are responsible for the peak solubilities. We chose Fe 2 O 3 as the basic material since this occurs in large amounts around damaged metal structures in rock salt mines in a proposed zone for storing vitrified radioactive wastes. Solubility measurement and paper chromatography show that Fe 2 O 3 dissolves in molten NaPO 3 + NaCl in air by reaction with the solvent to give double iron and sodium diphosphates and monophosphates in accordance with the initial solution-in-the-melt composition, the degree of equilibration, and the temperature. The elevated solubilities for initial NaCl contents close to 30 mole % are due to sodium triphosphates and tricyclophosphates present in these melts. Moessbauer spectroscopy confirms that double iron, europium and tin diphosphates and monophosphates containing sodium occur in these chloride-polyphosphate melts

  3. A review of the developments of radioxenon detectors for nuclear explosion monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Sivels, Ciara B.; McIntyre, Justin I.; Bowyer, Theodore W.; Kalinowski, Martin B.; Pozzi, Sara A.

    2017-09-27

    Developments in radioxenon monitoring since the implementation of the International Monitoring System are reviewed with emphasis on the most current technologies to improve detector sensitivity and resolution. The nuclear detectors reviewed include combinations of plastic and NaI(Tl) detectors, high purity germanium detectors, silicon detectors, and phoswich detectors. The minimum detectable activity and calibration methods for the various detectors are also discussed.

  4. Na(+),K (+)-ATPase as a docking station: protein-protein complexes of the Na(+),K (+)-ATPase.

    Science.gov (United States)

    Reinhard, Linda; Tidow, Henning; Clausen, Michael J; Nissen, Poul

    2013-01-01

    The Na(+),K(+)-ATPase, or sodium pump, is well known for its role in ion transport across the plasma membrane of animal cells. It carries out the transport of Na(+) ions out of the cell and of K(+) ions into the cell and thus maintains electrolyte and fluid balance. In addition to the fundamental ion-pumping function of the Na(+),K(+)-ATPase, recent work has suggested additional roles for Na(+),K(+)-ATPase in signal transduction and biomembrane structure. Several signaling pathways have been found to involve Na(+),K(+)-ATPase, which serves as a docking station for a fast-growing number of protein interaction partners. In this review, we focus on Na(+),K(+)-ATPase as a signal transducer, but also briefly discuss other Na(+),K(+)-ATPase protein-protein interactions, providing a comprehensive overview of the diverse signaling functions ascribed to this well-known enzyme.

  5. Characterization of Na+-linked and Na+-independent Cl-/HCO3- exchange systems in Chinese hamster lung fibroblasts

    International Nuclear Information System (INIS)

    Cassel, D.; Scharf, O.; Rotman, M.; Cragoe, E.J. Jr.; Katz, M.

    1988-01-01

    The PS120 variant of Chinese hamster lung fibroblasts which lacks Na + /H + exchange activity was used to investigate bicarbonate transport systems and their role in intracellular pH (pH/sub i/) regulation. When pH/sub i/ was decreased by acid load, bicarbonate caused pH/sub i/ increase and stimulated 36 Cl - efflux from the cells, both in a Na + -dependent manner. These results together with previous findings that bicarbonate stimulates 22 Na + uptake in PS120 cells demonstrate the presence of a Na + -linked Cl - /HCO 3 - exchange system. In cells with normal initial pH/sub i/, bicarbonate caused Na + -independent pH/sub i/ increase in Cl - -free solutions and stimulated Na + -independent 36 Cl - efflux, indicating that a Na + -independent Cl - /HCO 3 - exchanger is also present in the cell. Na + -linked and Na + -independent Cl - /HCO 3- exchange is apparently mediated by two distinct systems, since a [(tetrahydrofluorene-7-yl)oxy]acetic acid derivative selectively inhibits the Na + -independent exchanger. An additional distinctive features is a 10-fold lower affinity for chloride of the Na + -linked exchanger. The Na + -linked and Na + -independent Cl - /HCO 3 - exchange systems are likely to protect the cell from acid and alkaline load, respectively

  6. Na+ Influx Induced by New Antimalarials Causes Rapid Alterations in the Cholesterol Content and Morphology of Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Sudipta Das

    2016-05-01

    Full Text Available Among the several new antimalarials discovered over the past decade are at least three clinical candidate drugs, each with a distinct chemical structure, that disrupt Na+ homeostasis resulting in a rapid increase in intracellular Na+ concentration ([Na+]i within the erythrocytic stages of Plasmodium falciparum. At present, events triggered by Na+ influx that result in parasite demise are not well-understood. Here we report effects of two such drugs, a pyrazoleamide and a spiroindolone, on intraerythrocytic P. falciparum. Within minutes following the exposure to these drugs, the trophozoite stage parasite, which normally contains little cholesterol, was made permeant by cholesterol-dependent detergents, suggesting it acquired a substantial amount of the lipid. Consistently, the merozoite surface protein 1 and 2 (MSP1 and MSP2, glycosylphosphotidylinositol (GPI-anchored proteins normally uniformly distributed in the parasite plasma membrane, coalesced into clusters. These alterations were not observed following drug treatment of P. falciparum parasites adapted to grow in a low [Na+] growth medium. Both cholesterol acquisition and MSP1 coalescence were reversible upon the removal of the drugs, implicating an active process of cholesterol exclusion from trophozoites that we hypothesize is inhibited by high [Na+]i. Electron microscopy of drug-treated trophozoites revealed substantial morphological changes normally seen at the later schizont stage including the appearance of partial inner membrane complexes, dense organelles that resemble "rhoptries" and apparent nuclear division. Together these results suggest that [Na+]i disruptor drugs by altering levels of cholesterol in the parasite, dysregulate trophozoite to schizont development and cause parasite demise.

  7. PfGBP: una proteína de unión al telómero de Plasmodium falciparum

    Directory of Open Access Journals (Sweden)

    Eliana Calvo

    2015-01-01

    Full Text Available Los telómeros son estructuras complejas de ADN y proteína localizadas en el extremo de los cromosomas eucariotes. Su principal función es proteger el extremo cromosomal de ser reconocido y procesado como ADNs fracturado, evitando así eventos de recombinación y fusión que conducen a inestabilidad cromosomal. El ADN telomérico consta de secuencias cortas, repetidas una tras otra, ricas en guanina; la cadena rica en guanina se extiende formando una región de cadena sencilla denominada extremo 3´ protuberante. Las proteínas por su parte, se pueden clasificar en: dsBPs, o proteínas de unión a la cadena doble, GBPs aquellas que reconocen específicamente el extremo protuberante y, proteínas que las interconectan mediante interacciones proteína-proteína. El gen PF3D7_1006800 de Plasmodium falciparum codifica para una proteína putativa similar a una GBP de Criptosporidium parvum, con el fin de establecer si esta proteína de P. falciparum presenta la capacidad de unión al ADN telomérico del parásito, se produjo una proteína recombinante a partir de la región codificante del gen, se purificó y se utilizó en ensayos de unión a ADN, y en la generación de anticuerpos policlonales específicos contra PfGBP. Nuestros resultados indican que la proteína de P. falciparum es una proteína nuclear con capacidad de unión al ADN telomérico in vitro, por lo que podría ser parte del complejo proteico encargado de proteger y/o mantener el telómero in vivo.

  8. Use of a low energy proton accelerator for calibrating a large NaI(Tl) array in a high energy physics experiment

    International Nuclear Information System (INIS)

    Kirkbride, G.I.; O'Reilly, J.G.; Tompkins, J.C.

    1978-01-01

    The use of a 500 keV Van de Graaff proton accelerator to produce γ-rays in the range 4 - 18 MeV via nuclear reactions for the purpose of calibrating a large NaI(Tl) crystal array is reported. Data analysis indicates an energy calibration to approx. 1% over this range

  9. Na/K Pump and Beyond: Na/K-ATPase as a Modulator of Apoptosis and Autophagy

    Directory of Open Access Journals (Sweden)

    Cassiano Felippe Gonçalves-de-Albuquerque

    2017-04-01

    Full Text Available Lung cancer is a leading cause of global cancer deaths. Na/K-ATPase has been studied as a target for cancer treatment. Cardiotonic steroids (CS trigger intracellular signalling upon binding to Na/K-ATPase. Normal lung and tumour cells frequently express different pump isoforms. Thus, Na/K-ATPase is a powerful target for lung cancer treatment. Drugs targeting Na/K-ATPase may induce apoptosis and autophagy in transformed cells. We argue that Na/K-ATPase has a role as a potential target in chemotherapy in lung cancer treatment. We discuss the effects of Na/K-ATPase ligands and molecular pathways inducing deleterious effects on lung cancer cells, especially those leading to apoptosis and autophagy.

  10. Na/K Pump and Beyond: Na/K-ATPase as a Modulator of Apoptosis and Autophagy.

    Science.gov (United States)

    Felippe Gonçalves-de-Albuquerque, Cassiano; Ribeiro Silva, Adriana; Ignácio da Silva, Camila; Caire Castro-Faria-Neto, Hugo; Burth, Patrícia

    2017-04-21

    Lung cancer is a leading cause of global cancer deaths. Na/K-ATPase has been studied as a target for cancer treatment. Cardiotonic steroids (CS) trigger intracellular signalling upon binding to Na/K-ATPase. Normal lung and tumour cells frequently express different pump isoforms. Thus, Na/K-ATPase is a powerful target for lung cancer treatment. Drugs targeting Na/K-ATPase may induce apoptosis and autophagy in transformed cells. We argue that Na/K-ATPase has a role as a potential target in chemotherapy in lung cancer treatment. We discuss the effects of Na/K-ATPase ligands and molecular pathways inducing deleterious effects on lung cancer cells, especially those leading to apoptosis and autophagy.

  11. Subnitride chemistry: A first-principles study of the NaBa3N, Na5Ba3N, and Na16Ba6N phases

    International Nuclear Information System (INIS)

    Oliva, Josep M.

    2005-01-01

    An ab initio study on the electronic structure of the subnitrides NaBa 3 N, Na 5 Ba 3 N, and Na 16 Ba 6 N is performed for the first time. The NaBa 3 N and Na 5 Ba 3 N phases consist of infinite 1 ∞ [NBa 6/2 ] strands composed of face-sharing NBa 6 octahedra surrounded by a 'sea' of sodium atoms. The Na 16 Ba 6 N phase consist of discrete [NBa 6 ] octahedra arranged in a body-cubic fashion, surrounded by a 'sea' of sodium atoms. Our calculations suggest that the title subnitrides are metals. Analysis of the electronic structure shows partial interaction of N(2s) with Ba(5p) electrons in the lower energy region for NaBa 3 N and Na 5 Ba 3 N. However, no dispersion is observed for the N(2s) and Ba(5p) bands in the cubic phase Na 16 Ba 6 N. The metallic band below the Fermi level shows a strong mixing of N(2p), Ba(6s), Ba(5d), Ba(6p), Na(3s) and Na(3p) orbitals. The metallic character in these nitrides stems from delocalized electrons corresponding to hybridized 5d l 6s m 6p n barium orbitals which interact with hybridized 3s n 3p m sodium orbitals. Analysis of the electron density and electronic structure in these nitrides shows two different regions: a metallic matrix corresponding to the sodium atoms and the regions around them and heteropolar bonding between nitrogen and barium within the infinite 1 ∞ [NBa 6/2 ] strands of the NaBa 3 N and Na 5 Ba 3 N phases, and within the isolated [NBa 6 ] octahedra of the Na 16 Ba 6 N phase. The nitrogen atoms inside the strands and octahedra are negatively charged, the anionic character of nitrogens being larger in the isolated octahedra of the cubic phase Na 16 Ba 6 N, due to the lack of electron delocalization along one direction as opposed to the other phases. The sodium and barium atoms appear to be slightly negatively and positively charged, the latter to a larger extent. From the computed Ba-N overlap populations as well as the analysis of the contour maps of differences between total density and superposition of

  12. Calculations to support design of a nuclear material tracking system

    International Nuclear Information System (INIS)

    Carter, L.L.; Eggers, R.F.; Williams, T.L.

    1991-01-01

    The Westinghouse Hanford Company is developing a nuclear material tracking system called NTRAK for the US Department of Energy at the Savannah River site. The NTRAK system is designed to determine the position and approximate magnitude of packages of special nuclear material (SNM) moving through a nuclear plant. The NTRAK accomplishes this by using special assemblies of detectors called modules to measure the gamma radiation emitted by the SNM. After measurement, raw data are processed to determine the direction to and position of the gamma-ray source. In order for the NTRAK method of SNM tracking to work, the gamma-ray signal at the detector modules must be at least four standard deviations above background. This paper addresses the use of the Monte Carlo computer code for neutron and photon transport (MCNP) to (a) predict the radiation emitted by plutonium oxide sources and (b) predict the counting rate of NaI detectors measuring those sources

  13. Recurrent back pain after diskectomy: MRI findings MR of the postoperative lumbar spine; Recurrencia del dolor lumbar en la columna operada: Hallazgos en Resonancia Magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Aparicio, Rocio; Eguren, Leonor Z; Schinder, Humberto; Stur, Mariela [CIMA, Sanatorio Mapaci, Rosario, Santa Fe (Argentina)

    2008-07-01

    Purpose: To show the morphological changes in postoperative lumbar spine. Material and methods: We reviewed 128 Magnetic Resonance Imaging (MRI) studies of lumbar spine. All patients complained of low back pain and had a previous lumbar surgery (1 month to 8 years). All the examinations include axial and sagittal Gadopentate-dimeglumine enhanced T1 weighted imaging. Results: Only 7,8% have the normal appearance of the postoperative lumbar spine. Epidural scar was found in 69% of examinations; of this group, 72% showed radicular involvement, and 28% had no radicular involvement. Recurrent disc herniation was found in 14,8% of exams, using gadopentate-dimeglumine to assist the differentiation from epidural fibrosis; infections like spondylodiscitis and abscess in 12,5%. Other findings included arachnoiditis, pseudomeningoceles and seromas. Conclusions: MRI is a useful method to study the postoperative lumbar spine, specially when enhanced with gadopentate-dimeglumine. Enhanced images can differentiate two of the major complication like epidural fibrosis, and recurrent disc herniation. Spondylodiscitis are important and frequent too. Although the findings of complications in our series in the postoperative lumbar spine represent 92,18 %, these not always explain the symptomatology. Therefore, the interrelation is important with the surgeon to determine which abnormalities are clinically significant. (authors) [Spanish] Objetivo: Mostrar los hallazgos evidenciados en Resonancia Magnetica (RM) en pacientes operados de columna lumbar. Material y metodos: Se evaluaron retrospectivamente 128 estudios de RM de columna lumbar. Todos los pacientes consultaron por dolor lumbar y tenian antecedentes quirurgicos de un tiempo de evolucion que variaba entre 1 mes y 8 anos. En todos los casos el protocolo de estudio incluyo secuencias axiales y sagitales T1 con gadolinio, ademas del protocolo habitual. Resultados: Solo el 7,8 % de los estudios mostro los hallazgos postoperatorios

  14. WPŁYW WIEKU NA WYTRZYMAŁOŚĆ NA ŚCISKANIE BETONU MODYFIKOWANEGO DODATKIEM METAKAOLINITU

    Directory of Open Access Journals (Sweden)

    Janusz KONKOL

    Full Text Available W artykule przedstawiono wyniki badań wytrzymałości na ściskanie betonów modyfikowanych dodatkiem metakaolinitu po 2, 3, 7, 14, 28 i 56 dniach dojrzewania. Dodatek metakaolinitu użyto jako częściowy substytut cementu, dokonując wymiany 10% masy cementu na metakaolinit. Udział ten uznawany jest za optymalny z uwagi na inne niż wytrzymałość na ściskanie właściwości betonu, w tym trwałość betonu modyfikowanego metakaolinitem. Badania przeprowadzono także dla betonu tła, betonu bez dodatku metakaolinitu. Betony wykonano przy założeniu stałego stosunku woda/spoiwo, względnie woda/cement wynoszącego 0,45 oraz przy użyciu cementu portlandzkiego CEM I 32,5R, piasku kwarcowego frakcji do 2 mm oraz grysu bazaltowego frakcji do 16 mm. W celu uzyskania pożądanej konsystencji mieszanki betonowej zastosowano upłynniacz na bazie estrów polikarboksylowych. Uzyskane rezultaty badań potwierdziły wysoką aktywność pucolanową metakaolinitu już we wczesnym okresie dojrzewania betonu. W okresie między 3 a 7 dniem dojrzewania stwierdzono wolniejszy przyrost wytrzymałości na ściskanie w betonie niemodyfikowanym metakaolinitem, podczas gdy w betonie, w którym 10% masy cementu zastąpiono metakaolinitem uwidocznił się znaczący przyrost wytrzymałości na ściskanie. Po 2 dniach dojrzewania wytrzymałość na ściskanie betonu tła była nieznacznie wyższa od wytrzymałości na ściskanie betonu modyfikowanego. Korzystny wpływ dodatku metakaolinitu wynikający z jego wysokiej aktywności pucolanowej, jak również z uszczelniającego charakteru tego dodatku obserwowano jest zwłaszcza w okresie między 3 a 14 dniem dojrzewania. W tym okresie obserwowano znaczny przyrost wytrzymałości na ściskanie betonu modyfikowanego w porównaniu z wytrzymałością na ściskanie betonu tła. Po 7 i 14 dniach dojrzewania stwierdzono odpowiednio prawie 25% i 21% wzrost wytrzymałości na ściskanie na skutek użycia metakaolinitu.

  15. Teratological studies of DTPA-CaNa3, DTPA-ZnNa3 and quinamic acid in mice

    International Nuclear Information System (INIS)

    Luo Meichu; Ruan Tianming; Tong Shungao

    1989-01-01

    DTPA-CaNa 3 , DTPA-ZnNa 3 and quinamic acid are effective chelating agents for removing actinide elements from the body. In this experiment, different doses of DTPA-CaNa 3 , DTPA-ZnNa 3 and quinamic acid were given to mice on gestation days 6-10. Eight groups of mice received 0.8 and 2.0 mM/kg of DTPA-CaNa 3 , 3.8, 7.6, and 11.4 mM/kg of DTPA-ZnNa 3 and 0.42, 2.1, and 4.2 mM/kg of quinamic acid. Hypetonic saline and isotonic saline were given to two control groups. DTPA-CaNa 3 and quinamidic acid were found to be much more toxic to fetus of mice than DTPA-ZnNa 3 . When the doses of DTPA-CaMa 3 and quinamidic acid were 20 times higher than the human dose, the number of resorbed fetus was increased and the number and weight of live fetus were reduced. The result of injection with 7.6 mM/kg (200 times of human dose)DTPA-ZnNa 3 and that of injection with isotonic saline are the same. Therefore, we suggest that the DTPA-CaNa 3 and quinamidic acid should not be given to pregnant woman, if chelation therapy is needed, while the much safer DTPA-ZnNa 3 could be used

  16. Interaction between a plasma membrane-localized ankyrin-repeat protein ITN1 and a nuclear protein RTV1

    Energy Technology Data Exchange (ETDEWEB)

    Sakamoto, Hikaru [Department of Bioproduction, Faculty of Bioindustry, Tokyo University of Agriculture, 196 Yasaka, Abashiri-shi, Hokkaido 093-2422 (Japan); Sakata, Keiko; Kusumi, Kensuke [Department of Biology, Faculty of Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Kojima, Mikiko; Sakakibara, Hitoshi [RIKEN Plant Science Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045 (Japan); Iba, Koh, E-mail: koibascb@kyushu-u.org [Department of Biology, Faculty of Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)

    2012-06-29

    Highlights: Black-Right-Pointing-Pointer ITN1, a plasma membrane ankyrin protein, interacts with a nuclear DNA-binding protein RTV1. Black-Right-Pointing-Pointer The nuclear transport of RTV1 is partially inhibited by interaction with ITN1. Black-Right-Pointing-Pointer RTV1 can promote the nuclear localization of ITN1. Black-Right-Pointing-Pointer Both overexpression of RTV1 and the lack of ITN1 increase salicylic acids sensitivity in plants. -- Abstract: The increased tolerance to NaCl 1 (ITN1) protein is a plasma membrane (PM)-localized protein involved in responses to NaCl stress in Arabidopsis. The predicted structure of ITN1 is composed of multiple transmembrane regions and an ankyrin-repeat domain that is known to mediate protein-protein interactions. To elucidate the molecular functions of ITN1, we searched for interacting partners using a yeast two-hybrid assay, and a nuclear-localized DNA-binding protein, RTV1, was identified as a candidate. Bimolecular fluorescence complementation analysis revealed that RTV1 interacted with ITN1 at the PM and nuclei in vivo. RTV1 tagged with red fluorescent protein localized to nuclei and ITN1 tagged with green fluorescent protein localized to PM; however, both proteins localized to both nuclei and the PM when co-expressed. These findings suggest that RTV1 and ITN1 regulate the subcellular localization of each other.

  17. Defense Nuclear Material Stewardship Integrated Inventory Information Management System (IIIMS).

    Energy Technology Data Exchange (ETDEWEB)

    Aas, Christopher A.; Lenhart, James E.; Bray, Olin H.; Witcher, Christina Jenkin

    2004-11-01

    Sandia National Laboratories was tasked with developing the Defense Nuclear Material Stewardship Integrated Inventory Information Management System (IIIMS) with the sponsorship of NA-125.3 and the concurrence of DOE/NNSA field and area offices. The purpose of IIIMS was to modernize nuclear materials management information systems at the enterprise level. Projects over the course of several years attempted to spearhead this modernization. The scope of IIIMS was broken into broad enterprise-oriented materials management and materials forecasting. The IIIMS prototype was developed to allow multiple participating user groups to explore nuclear material requirements and needs in detail. The purpose of material forecasting was to determine nuclear material availability over a 10 to 15 year period in light of the dynamic nature of nuclear materials management. Formal DOE Directives (requirements) were needed to direct IIIMS efforts but were never issued and the project has been halted. When restarted, duplicating or re-engineering the activities from 1999 to 2003 is unnecessary, and in fact future initiatives can build on previous work. IIIMS requirements should be structured to provide high confidence that discrepancies are detected, and classified information is not divulged. Enterprise-wide materials management systems maintained by the military can be used as overall models to base IIIMS implementation concepts upon.

  18. Advanced Safeguards Technology Road-map for the Global Nuclear Energy Partnership

    International Nuclear Information System (INIS)

    Miller, M.C.; Tobin, S.; Smith, L.E.; Ehinger, M.; Dougan, A.; Cipiti, B.; Bakel, A.; Bean, R.

    2008-01-01

    Strengthening the nonproliferation regime, including advanced safeguards, is a cornerstone of the Global Nuclear Energy Partnership (GNEP). To meet these challenges, the Safeguards Campaign was formed, whose mission is to provide research and technology development for the foundation of next generation safeguards systems for implementation in U.S. GNEP facilities. The Safeguards Campaign works closely with the Nuclear Nonproliferation and International Security department (NA-24) of NNSA (National Nuclear Safety Administration) to ensure that technology developed for domestic safeguards applications are optimum with respect to international safeguards use. A major milestone of the program this year has been the development of the advanced safeguards technology road-map. This paper will broadly describe the road-map, which provides a path to next generation safeguards systems including advanced instrumentation; process monitoring; data integration, protection, and analysis; and system level evaluation and knowledge extraction for real time applications. (authors)

  19. Na-ion dynamics in Quasi-1D compound NaV2O4

    International Nuclear Information System (INIS)

    Månsson, M; Umegaki, I; Nozaki, H; Higuchi, Y; Sugiyama, J; Kawasaki, I; Watanabe, I; Sakurai, H

    2014-01-01

    We have used the pulsed muon source at ISIS to study high-temperature Na-ion dynamics in the quasi-one-dimensional (Q1D) metallic antiferromagnet NaV 2 O 4 . By performing systematic zero-field and longitudinal-field measurements as a function of temperature we clearly distinguish that the hopping rate increases exponentially above T diff ≈ 250 K. The data is well fitted to an Arrhenius type equation typical for a diffusion process, showing that the Na-ions starts to be mobile above T diff . Such results make this compound very interesting for the tuning of Q1D magnetism using atomic-scale ion-texturing through the periodic potential from ordered Na-vacancies. Further, it also opens the door to possible use of NaV 2 O 4 and related compounds in energy related applications

  20. Os trigonum tarsi syndrome. Magnetic Resonance features; Sindrome dell'os trigonum tarsi. Ruolo della Risonanza Magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Iovane, A.; Finazzo, M.; Carcione, A.; De Maria, M; Lagalla, R. [Palermo Policlinico Univ. P. Giaccone, Palermo (Italy). Ist. di Radiologia; Midiri, M. [Bari Policlinico Univ., Bari (Italy). Ist. di Radiologia

    2000-02-01

    aspect of the tibia, or hypo mobility to pseudoarthrosis. Forced plantar flexion acquisitions are particularly useful in this condition because can demonstrate the mechanism of injury. [Italian] L'os trigonum tarsi e' un osso accessorio del piede localizzato in sede posterolaterale rispetto al tubercolo esterno dell'astragalo e di solito non da' alcuna sintomatologia. In particolari condizioni, che comportano sollecitazioni o microtraumi ripetuti nel tempo a livello del retropiede puo' essere responsabile di talalgia posteriore realizzando la cosidetta sindrome dell'os trigonum tarsi. Il dolore e' localizzato nella sede preachillea. La diagnosi tuttavia risulta particolarmente complessa i quanto numerose altre forme patologiche si manifestano con la medesima sintomatologia clinica. Con la radiologia tradizionale e' possibile dimostrare la presenza dell'os trigonum e le sue eventuali alterazioni morfo-strutturali. La RM (Risonanza Magnetica) di contro consente non solo di identificare le alterazioni strutturali dell'osso ma anche di riconoscere le lesioni associate dei tessuti molli. Sono stati studiati con RM nove pazienti affetti da sindrome dell'os trigonum tarsi. I pazienti sono stati esaminati nella posizione supina con il piede in posizione indifferente e successivamente bloccato nella flessione plantare. Lo studio e' stato condotto con magnete superconduttivo da 0,5 T impiegando una bobina dedicata per le estremita'. Sono state utilizzate sequenze spin-echo T1, gradient-echo T2* e fast inversion recovery secondo piani di scansione assiali e saggitali. In tutti i pazienti esaminati sono state valutate: sede e morfologia dell'os trigonum; caratteristiche dell'intensita' del segnale delle strutture ossee, cartilaginee e dei tessuti adiacenti; presenza di eventuali lesioni tendinee associate. Non sono state osservate anomalie di sede ne' di forma dell'os trigonum. L

  1. Degeneração oxychromatica ("inclusões intranucleares" na febre amarella

    Directory of Open Access Journals (Sweden)

    C. Magarinos Torres

    1931-05-01

    Full Text Available 1- No interior do nucleo de cellulas hepaticas de Macacus rhesus e M. cynomolgus (figs. 13-34 inoculado com o virus da febre amarella e de cellulas hepaticas de doentes de febre amarella (figs. 61-65 e 68-69 ocorre o processo regressivo referido na literatura sob o nome de «degeneração oxychromatica». Tal processo apresenta grande intensidade nos macacos, sendo, porém, assaz escasso no material humano colhido em autopsias. Esta alteração está intimamente associada ao effeito nocivo causado pelo proprio virus da febre amarella, sendo, neste sentido, a unica alteração verdadeiramente especifica na febre amarella. Não foram encontradas alterações do cytoplasma nem granulos intracellulares que tivessem relação com o virus da febre amarella. Assim sendo, a febre amarella pertencerá ao grupo de doenças de virus filtraveis produzindo alterações cellulares caracteristicas ou corpusculos especificos, exclusivamente limitados ao nucleo. Deve ser incluida, portanto no grupo karyo-oikon da classificação de Lipschütz, juntamente com herpes, varicella, virus III do coelho, «submaxillary disease», etc. Como acontece em geral, nas doenças de virus filtraveis, formando inclusões intracellulares, observa-se na febre amarella que a inclusão celular especifica predomina ou existe exclusivamente em determinada especie cellular. Até agora, no nosso material só conseguimos evidenciar a degeneração oxychromatica da febre amarella na cellula hepatica. Quando existe, porém, a sua abundancia é notavel, não raro attingido a quasi totalidade das cellulas hepaticas nos cortes histologicos examinados. Esse facto não poude ser observado nos casos humanos que examinamos,provavelmente em virtude de condições proprias do virus no homem e da phase da molestia na qual foi retirado o material para estudo. Nas cellulas da camada cortical das suprarenaes de M. rhesus infectados encontramos aspectos nucleares suggestivos de degenera

  2. Securing a better future for all: Nuclear techniques for global development and environmental protection. NA factsheet on nuclear sciences and applications: Applying 21st century nuclear science to 21st century problems

    International Nuclear Information System (INIS)

    2012-01-01

    By enhancing the integration across various thematic areas, the IAEA plays a role in helping to address today's emerging challenges. In radiation medicine, for example, nuclear technology is used for the diagnosis and treatment of major non-communicable diseases such as cancer and cardiovascular disorders. The Human Health Campus at http://humanhealth.iaea.org provides on-line resources and learning for health professionals working in radiation medicine. Responding to the world cancer crisis, the IAEA developed a unique initiative, the Programme of Action for Cancer Therapy which works closely with the World Health Organization (WHO) through the WHO-IAEA Joint Programme on Cancer Control. The programme aims at providing assistance to Member States to adopt comprehensive national cancer control programmes that encompass early detection, prevention, cancer diagnosis and treatment and palliative care. In a joint division with the Food and Agriculture Organization of the United Nations, the IAEA assists Member States in applying nuclear techniques to alleviate challenges in food safety, food security and sustainable agricultural development. The IAEA has made significant contributions to helping developing countries adopt sterile insect techniques to suppress and eradicate insect pests that pose a threat to human and to animal health. Using scientific methods based on the tracing of isotopes, the IAEA is improving the management of the world's freshwater resources, a key aspect of sustainable development in the face of climate change. The IAEA also helps Member States monitor known sites of radioactive contamination, as manifested by their ongoing efforts in Japan after the incident at Fukushima. Radioisotope products and radiation technology are essential components for applications across all fields, be it medicine, industry, or agriculture. The demand for the most used radioisotopes has been steadily increasing, such as, for example, fission produced 99Mo and 99m

  3. Design of single-walled NaK capsules for fast breeder fuel pins irradiation (IVO-FR2-Vg7 program)

    International Nuclear Information System (INIS)

    Lopez Jimenez, J.; Hafner, H.E.

    1979-01-01

    In Frame of the Joint Irradiation Program IVO-FR2 between the Nuclear Research Centre of Karlsruhe (RFA) and the Junta de Energia Nuclear (Spain) is carried out in the FR2 reactor (Karlsruhe) the irradiation of 12 mixed-oxide fuel rods of 172 mm length. These test rods are first irradiated under various conditions in four modified FR2 capsule (Typ 7). Two versions of single-walled NaK (78% K) are used for this purpose. This report contains the design and description of these two capsule versions as well as the considerations required to oftain the operations licence, supplemented by the relevant figures. (author)

  4. O Passeio Público do Rio de Janeiro na Literatura, na Pintura e na Fotografia do Século XIX

    Directory of Open Access Journals (Sweden)

    Solange de Aragão

    2012-06-01

    Full Text Available Este artigo tem como objetivo geral e mais amplo chamar a atenção dos pesquisadores para a importância da literatura, da pintura e da fotografia como fontes documentais para a construção da História do Paisagismo no Brasil por meio de um estudo de caso muito particular: o Passeio Público do Rio de Janeiro no século XIX. São objetivos específicos apresentar e analisar o modo como esse espaço livre público aparece na literatura, na pintura e na fotografia desse período, considerando suas transformações paisagísticas.

  5. Use of microcontroller in gamma-ray spectrometer construction using NaI(Tl) sensor, with emphasis in multichannel analyzer, to applications in nuclear and environmental geophysics

    International Nuclear Information System (INIS)

    Silva, Nilton

    2005-01-01

    In this work of nuclear geophysical instrumentation the main purpose was the development of a gamma-ray spectrometer prototype with multi channel analyzer, since the spectroscopic amplifier until your firmware. The heart of the digital part was an ATMEL 8 bits microcontroller (AT89S8252). All circuits were made and assembled in the Laboratory of Applied Geophysical Instrumentation (LIGA) of IAG-USP. A microcontroller software was completely developed in C ANSI language using the Small Device C Compiler version 2.4.8, that is a free software distributed under General Public License (GPL). At first, microcontroller was used to change all digital circuit of one classic SCINTREX GAD-6 differential gamma-ray spectrometer. Measurement times with order of 2 days became possible, and it could work in non climate ambient. Then, after this stage, had been started the development of a multichannel analyzer (MCA) working in pulse height analyzer mode with 4096 channels capacity, to use in many kinds of nuclear detection. Besides it, was developed an automatic gain system for photopeak stabilization, by the use of one radioactive source ( 133 Ba). This automatic gain system is very important in the case of NaI(Tl) scintillometric detectors, due PMT sensitivity with temperature and aging of some laboratory electronic circuits. Two power supplies with high stability, using pulse width modulation (PWM) techniques were developed, in order to all system became free of electrical line break off. One PWM power polarizes a photo multiplier tube (PMT) with high voltage and another supplies remaining developed circuits. Calibration in energy using standards sources 137 Cs and 60 Co showed that gamma detector developed has a good linearity and low thermal drift, even working in absent of air-conditioned. Concentrations measurements of K, U and Th were made in samples of soils, vegetables, etc. (author)'

  6. Solubility of NaNd(CO3)2.6H2O(c) in concentrated Na2CO3 and NaHCO3 solutions

    International Nuclear Information System (INIS)

    Rao, L.; Rai, D.; Felmy, A.R.; Fulton, R.W.; Novak, C.F.

    1996-01-01

    NaNd(CO 3 ) 2 x 6 H 2 O(c) was identified to be the final equilibrium solid phase in suspensions containing concentrated sodium carbonate (0.1 to 2.0 M) and sodium bicarbonate (0.1 to 1.0 M), with either NaNd(CO 3 ) 2 x 6 H 2 O(c) or Nd 2 (CO 3 ) 3 x xH 2 O(s) as initial solids. A thermodynamic model, based on Pitzer's specific into-interaction approach, was developed to interpret the solubility of NaNd(CO 3 ) 2 x 6 H 2 O(c) as functions of sodium carbonate and sodium bicarbonate concentrations. In this model, the solubility data of NaNd(CO 3 ) 2 x 6 H 2 O(c) were explained by assuming the formation of NdCO 3 + , Nd(CO 3 ) 2 - and Nd(CO 3 ) 3 3- species and invoking the specific ion interactions between Na + and Nd(CO 3 ) 3 3- . Ion interaction parameters for Na + -Nd(CO 3 ) 3 3- were developed to fit the solubility data. Based on the model calculations, Nd(CO 3 ) 3 3- was the predominant aqueous neodymium species in 0.1 to 2 M sodium carbonate and 0.1 to 1 M sodium bicarbonate solutions. The logarithm of the NaNd(CO 3 ) 2 x 6 H 2 O solubility product (NaNd(CO 3 ) 2 x 6 H 2 O(c)=Na + +Nd 3+ +2 CO 3 2- +6 H 2 O) was calculated to be -21.39. This model also provided satisfactory interpretation of the solubility data of the analogous Am(III) system in less concentrated carbonate and bicarbonate solutions. (orig.)

  7. Research Programs in the Field of Nuclear Power Engineering and Technologies in the Republic of Kazakhstan

    International Nuclear Information System (INIS)

    Cherepnin, Yu. S.; Takibaev, Zh. S.

    2000-01-01

    In 1991 the Semipalatinsk Test Site (STS) was closed under the decree of President of the Republic of Kazakhstan, N.A. Nazarbayev. Later, the National Nuclear Center of the Republic of Kazakhstan (NNC RK) was established under President's decree 779 dated May 15 1992. A range of NNC RK activity was specified in the decree: ' To create National Nuclear Center of the Republic of Kazakhstan on the basis of the former Semipalatinsk Test Site and appropriate scientific organizations and facilities situated in the Republic of Kazakhstan with a view to conduct work on radiation safety and ecology, investigation of problems related to utilization and radioactive waste disposal, development work in the field of nuclear technology and nuclear power engineering'. Tasks outlined in this decree, later on, became the work program of NNC RK

  8. Applicability of iron phosphate glass medium for loading NaCl originated from seawater used for cooling the stricken power reactors

    International Nuclear Information System (INIS)

    Amamoto, Ippei; Kobayashi, Hidekazu; Yokozawa, Takuma; Yamashita, Teruo; Nagai, Takayuki; Kitamura, Naoto; Takebe, Hiromichi; Mitamura, Naoki; Tsuzuki, Tatsuya

    2013-01-01

    As the part of investigation for immobilization of the sludge as one of the radioactive wastes arising from the treatment of contaminated water at Fukushima Dai-ichi nuclear power plant, applicability of vitrification method has been evaluated as a candidate technique. The aim of this study is to evaluate the influence of NaCl as one of the main constituents of sludge, on glass formation and glass properties. Two kinds of iron phosphate glass (IPG) media in the xFe 2 O 3 -(100-x)P 2 O 5 , with x=30 and 35 (mol%) were chosen and the glass formation, structure and properties including density, coefficient of thermal expansion, glass transition temperature, onset crystallization temperature and chemical durability of NaCl-loaded IPG were studied. The results are summarized as follows. Sodium chloride, NaCl could be loaded into IPG medium as Na 2 O and Cl contents and their loading ratio could be up to 19 and 15 mol%, respectively. Majority of Cl content of raw material NaCl was thought to be volatilized during glass melting. Loading NaCl into IPG induces to de-polymerize glass network of phosphate chains, leads to decrease both glass transition and onset crystallization temperatures, and to increase coefficient of thermal expansion. NaCl-loaded IPG indicated good chemical durability in case of using 35Fe 2 O 3 - 65P 2 O 5 medium. (authors)

  9. Nuclear magnetic resonance and the question of 5F electron localization in the actinides

    International Nuclear Information System (INIS)

    Fradin, F.Y.

    1976-01-01

    Nuclear magnetic resonance results are presented for a number of NaCl-type compounds and cubic Laves-phase type compounds of uranium, neptunium, and plutonium. Special emphasis is placed on the Knight shift and spin-lattice relaxation time measurements and their interpretation in terms of localized or itinerant pictures of the 5Line integral electrons

  10. Research achievements in Bangladesh agriculture using nuclear techniques

    Energy Technology Data Exchange (ETDEWEB)

    Sattar, M.A. [Bangladesh Institute of Nuclear Agriculture, Mymensingh, (Bangladesh)

    1997-10-01

    Application of isotope and radiation techniques in Bangladesh agriculture has been initiated in 1961 with the establishment of Atomic Energy Agricultural Research Centre, Dhaka under the then Pakistan Atomic Energy Commission. The activity of the centre was strengthened and upgraded to the level of an institute as a constituent organization of Bangladesh Atomic Energy Commission in 1972. It was further reorganized, made an autonomous research organization under the Ministry of Agriculture in 1982 and renamed as Bangladesh Institute of Nuclear Agriculture. The other organizations involved in nuclear agricultural research are Institute of Food and Radiation Biology and Bangladesh Agricultural University. A number of technologies have been developed using nuclear techniques that imparted on agricultural development. Sixteen new crops were developed using physical (200-700 Gy gamma rays) and chemical mutagen (NaN{sub 3}). Soil fertility and plant nutrition technologies were developed using both stable and radio isotopes. The improved feeding strategies and utilization of locally available low quality feed material (rice straw) were determined using {sup 51}Cr-EDTA and {sup 125}I in order to have better livestock growth and reproduction ability. Several constraints related to nuclear research were identified. Increased government commitment and international cooperation are of the utmost importance for effective utilization of the benefits of nuclear technology and to face the increasing demand for food for the ever increasing population in years to come 32 refs., 1 tab.

  11. Structural radioactive waste from 'retubing/refurbishment' of Embalse nuclear power plant. Regulatory perspective

    International Nuclear Information System (INIS)

    Alvarez, Daniela E.; Lee Gonzales, Horacio M.; Medici, Marcela A.; Piumetti, Elsa H.

    2009-01-01

    Unlike the building of a new nuclear reactor, the 'retubing / refurbishment' of nuclear reactors that have been in operation for many years, involves the replacement of components in a radioactive environment. This requires a carefully planned radiation protection program to ensure protection of workers, the public and the environment as well as a radioactive waste management program for those radioactive waste generated during the process, which go beyond those generated during the normal operation and maintenance of the plant. Nucleoelectrica Argentina Sociedad Anonima (NA-SA) is scheduled to conduct the Life Extension Process of Embalse Nuclear Power Plant (CNE) which essentially consist of 'retubing / refurbishment' of the installation. The Nuclear Regulatory Authority (ARN) will then have an important activity related to the above process. In particular, this paper will describe some points of interest related to the generation and management of radioactive waste during the 'retubing / refurbishment' of the CNE, from the regulatory point of view. (author)

  12. Nuclear fuel elements

    International Nuclear Information System (INIS)

    Kawada, Toshiyuki; Hirayama, Satoshi; Yoneya, Katsutoshi.

    1980-01-01

    Purpose: To enable load-depending operation as well as moderation for the restriction of operation conditions in the present nuclear reactors, by specifying the essential ingredients and the total weight of the additives to UO 2 fuel substances. Constitution: Two or more additives selected from Al 2 O 3 , B 2 O, CaO, MgO, SiO 2 , Na 2 O and P 2 O 5 are added by the total weight of 2 - 5% to fuel substances consisting of UO 2 or a mixture of UO 2 and PuO 2 . When the mixture is sintered, the strength of the fuel elements is decreased and the fuel-cladding interactions due to the difference in the heat expansion coefficients between the ceramic fuel elements and the metal claddings are decreased to a substantially harmless degree. (Horiuchi, T.)

  13. Observables in muon capture on 23Na and the effective weak couplings ga and gp

    International Nuclear Information System (INIS)

    Johnson, B.L.; Gorringe, T.P.; Armstrong, D.S.; Bauer, J.; Hasinoff, M.D.; Kovash, M.A.; Measday, D.F.; Moftah, B.A.; Porter, R.; Wright, D.H.

    1996-01-01

    We report measurements of capture rates and hyperfine dependences in muon capture on 23 Na to various states in Ne and F isotopes. We also report comparisons of the capture rates and hyperfine dependences for six 23 Na → 23 Ne transitions with the 1s-0d shell model with the empirical effective interaction of Brown and Wildenthal and the realistic effective interaction of Kuo and Brown. Fits to the data with the Brown and Wildenthal interaction yield an effective coupling g a = -1.01 ± 0.07 and an effective coupling ratio g p /g a = 6.5 ± 2.4. The value of g a is consistent with values of g a extracted from β + /β - decay and (p,n)/(n,p) charge exchange data, and the value of g p /g a is consistent with the predictions of PCAC and pion-pole dominance. We evaluate the nuclear model dependence of these values of g a and g p /g a and examine the role of the Gamow-Teller and other matrix elements in the 23 Na → 23 Ne transitions. copyright 1996 The American Physical Society

  14. Design of nuclear desalination concentrate plant by using zero discharge desalination concept for Bangka Island

    International Nuclear Information System (INIS)

    Erlan Dewita, Siti Alimah

    2015-01-01

    Nuclear desalination is a process to separate salt of seawater by using nuclear energy. Desalination concentrate is a problem in nuclear desalination. Desalination concentrate is sometimes discharged directly into the seawater, therefore it can affects the water quality of beach and rise negative effects on the biota in the vicinity of the output. ZDD (Zero Discharge Desalination) concept can be applied to minimized environment impact. This study is conducted by using PWR type NPP as nuclear heat source and using ZDD concept to process desalination waste. ZDD is a concept for processing of desalination concentrate into salt and chemical products which have economic values. Objectives of this study is to design nuclear desalination concentrate processing plant in Bangka Island. The methodology is literature assessment and calculation with excel programme. The results of this study shows that the main the products are NaCl (pharmaceutical salt) and cakes BaSO4, Mg(OH)2BaCO3 as by products. (author)

  15. Mechanism of μ-conotoxin PIIIA binding to the voltage-gated Na+ channel NaV1.4.

    Directory of Open Access Journals (Sweden)

    Rong Chen

    Full Text Available Several subtypes of voltage-gated Na+ (NaV channels are important targets for pain management. μ-Conotoxins isolated from venoms of cone snails are potent and specific blockers of different NaV channel isoforms. The inhibitory effect of μ-conotoxins on NaV channels has been examined extensively, but the mechanism of toxin specificity has not been understood in detail. Here the known structure of μ-conotoxin PIIIA and a model of the skeletal muscle channel NaV1.4 are used to elucidate elements that contribute to the structural basis of μ-conotoxin binding and specificity. The model of NaV1.4 is constructed based on the crystal structure of the bacterial NaV channel, NaVAb. Six different binding modes, in which the side chain of each of the basic residues carried by the toxin protrudes into the selectivity filter of NaV1.4, are examined in atomic detail using molecular dynamics simulations with explicit solvent. The dissociation constants (Kd computed for two selected binding modes in which Lys9 or Arg14 from the toxin protrudes into the filter of the channel are within 2 fold; both values in close proximity to those determined from dose response data for the block of NaV currents. To explore the mechanism of PIIIA specificity, a double mutant of NaV1.4 mimicking NaV channels resistant to μ-conotoxins and tetrodotoxin is constructed and the binding of PIIIA to this mutant channel examined. The double mutation causes the affinity of PIIIA to reduce by two orders of magnitude.

  16. Muscle K+, Na+, and Cl- disturbances and Na+-K+ pump inactivation: implications for fatigue

    DEFF Research Database (Denmark)

    McKenna, Michael J; Bangsbo, Jens; Renaud, Jean-Marc

    2008-01-01

    (+)-ATPase activity during exercise stabilizes Na(+) and K(+) concentration gradients and membrane excitability and thus protects against fatigue. However, during intense contraction some Na(+)-K(+) pumps are inactivated and together with further ionic disturbances, likely precipitate muscle fatigue.......Membrane excitability is a critical regulatory step in skeletal muscle contraction and is modulated by local ionic concentrations, conductances, ion transporter activities, temperature, and humoral factors. Intense fatiguing contractions induce cellular K(+) efflux and Na(+) and Cl(-) influx......, causing pronounced perturbations in extracellular (interstitial) and intracellular K(+) and Na(+) concentrations. Muscle interstitial K(+) concentration may increase 1- to 2-fold to 11-13 mM and intracellular K(+) concentration fall by 1.3- to 1.7-fold; interstitial Na(+) concentration may decline by 10 m...

  17. Nuclear law - Nuclear safety

    International Nuclear Information System (INIS)

    Pontier, Jean-Marie; Roux, Emmanuel; Leger, Marc; Deguergue, Maryse; Vallar, Christian; Pissaloux, Jean-Luc; Bernie-Boissard, Catherine; Thireau, Veronique; Takahashi, Nobuyuki; Spencer, Mary; Zhang, Li; Park, Kyun Sung; Artus, J.C.

    2012-01-01

    This book contains the contributions presented during a one-day seminar. The authors propose a framework for a legal approach to nuclear safety, a discussion of the 2009/71/EURATOM directive which establishes a European framework for nuclear safety in nuclear installations, a comment on nuclear safety and environmental governance, a discussion of the relationship between citizenship and nuclear, some thoughts about the Nuclear Safety Authority, an overview of the situation regarding the safety in nuclear waste burying, a comment on the Nome law with respect to electricity price and nuclear safety, a comment on the legal consequences of the Fukushima accident on nuclear safety in the Japanese law, a presentation of the USA nuclear regulation, an overview of nuclear safety in China, and a discussion of nuclear safety in the medical sector

  18. Il nucleo terrestre: il cuore magnetico della Terra

    OpenAIRE

    De Santis, A.

    2006-01-01

    Il campo magnetico terrestre è una proprietà intrinseca del nostro pianeta e di altri oggetti del sistema solare. Il Sole stesso possiede un forte campo magnetico che si inverte quasi ciclicamente ogni 10-11 anni; tale comportamento è visibile attraverso la medesima ciclicità delle macchie solari che denotano sulla superficie l’intensa attività magnetica della nostra stella. Il campo magnetico terrestre è importantissimo per la vita sulla Terra. Esso protegge il pianeta dalle p...

  19. Control optimo de par para maquinas SynRM aplicadas a vehiculo electrico

    OpenAIRE

    Trancho, Elena; Ibarra, E.; Arias, A.; Kortabarria, I.

    2017-01-01

    Las maquinas de reluctancia sincrona asistidas por imanes estan atrayendo un considerable interes como alternativa a las maquinas sıncronas de imanes permanentes para su uso en sistemas de propulsion de vehıculos electricos. El control optimo de estas maquinas (incluyendo operacion en debilitamiento de campo) puede resultar complejo, ya que estas son, por lo general, muy sensibles al fenomeno de la saturacion magnetica. En este articulo se trata su control, desde los reguladores hasta el prec...

  20. Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps

    Science.gov (United States)

    Vedovato, Natascia

    2014-01-01

    A single Na+/K+-ATPase pumps three Na+ outwards and two K+ inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na+ than K+ generates outward current across the cell membrane. Less well understood is the ability of Na+/K+ pumps to generate an inward current of protons. Originally noted in pumps deprived of external K+ and Na+ ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K+ and Na+ concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na+ release from phosphorylated Na+/K+ pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na+/K+ pumps that enables proton import is not required for completion of the 3 Na+/2 K+ transport cycle. However, the back-step occurs readily during Na+/K+ transport when external K+ ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na+-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na+ and K+ ions that passes through binding site II. The inferred occurrence of Na+/K+ exchange and H+ import during the same conformational cycle of a single molecule identifies the Na+/K+ pump as a hybrid transporter. Whether Na+/K+ pump–mediated proton inflow may have any physiological or pathophysiological significance remains to be clarified. PMID

  1. Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps.

    Science.gov (United States)

    Vedovato, Natascia; Gadsby, David C

    2014-04-01

    A single Na(+)/K(+)-ATPase pumps three Na(+) outwards and two K(+) inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na(+) than K(+) generates outward current across the cell membrane. Less well understood is the ability of Na(+)/K(+) pumps to generate an inward current of protons. Originally noted in pumps deprived of external K(+) and Na(+) ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K(+) and Na(+) concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na(+) release from phosphorylated Na(+)/K(+) pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na(+)/K(+) pumps that enables proton import is not required for completion of the 3 Na(+)/2 K(+) transport cycle. However, the back-step occurs readily during Na(+)/K(+) transport when external K(+) ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na(+)-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na(+) and K(+) ions that passes through binding site II. The inferred occurrence of Na(+)/K(+) exchange and H(+) import during the same conformational cycle of a single molecule identifies the Na(+)/K(+) pump as a hybrid transporter. Whether Na(+)/K(+) pump-mediated proton inflow may have any physiological or

  2. Environmental radiation monitoring around the nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Woo; Choi, Geun Sik and others

    2001-02-01

    Environmental Radiation Monitoring was carried out with measurement of environment. Radiation and environmental radioactivity analysis around KAERI nuclear facilities and Seoul Research Reactor. The results of environmental radiation monitoring around KAERI nuclear facilities and Seoul Research Reactor are the follows : The average level of environmental radiation dose measured by NaI scintillation counter and accumulated radiation dose by TLD was almost same level compared with the past years. Gross {alpha}, {beta} radioactivity in environmental samples showed a environmental level. {gamma}-radionuclides in water samples were not detected. But only radionuclide K-40, which is natural radionuclide, was detected in the all samples and Cs-137 was detected in the surface soil and discharge sediment. The average level of environmental radiation dose around Seoul Research Reactor was almost same level compared with the past years, and Be-7 and Cs-137 were detected in some surface soil and discharge sediment by {gamma}-spectrometry.

  3. Environmental radiation monitoring around the nuclear facilities

    International Nuclear Information System (INIS)

    Lee, Chang Woo; Choi, Young Ho

    2000-02-01

    Environmental radiation monitoring was carried out with measurement of environment radiation and environmental radioactivity analysis around KAERI nuclear facilities and Seoul Research Reactor. The results of environmental radiation monitoring around KAERI nuclear facilities and Seoul Research Reactor are the follows: The average level of environmental radiation dose measured by NaI scintillation counter and accumulated radiation dose by TLD was almost some level compared with the past years. Gross α, β radioactivity in environmental samples showed a environmental level. γ-radionuclides in water sample were not detected. But only radionuclide K-40, which is natural radionuclide, was detected in the all samples and Cs-137 was detected in the surface soil and discharge sediment. The average level of environmental radiation dose around Seoul Research Reactor was almost same level compared with the past years, and Be-7 and Cs-137 were detected in some surface soil and discharge sediment by γ-spectrometry. (author)

  4. Environmental radiation monitoring around the nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Woo; Choi, Young Ho

    2000-02-01

    Environmental radiation monitoring was carried out with measurement of environment radiation and environmental radioactivity analysis around KAERI nuclear facilities and Seoul Research Reactor. The results of environmental radiation monitoring around KAERI nuclear facilities and Seoul Research Reactor are the follows: The average level of environmental radiation dose measured by NaI scintillation counter and accumulated radiation dose by TLD was almost some level compared with the past years. Gross {alpha}, {beta} radioactivity in environmental samples showed a environmental level. {gamma}-radionuclides in water sample were not detected. But only radionuclide K-40, which is natural radionuclide, was detected in the all samples and Cs-137 was detected in the surface soil and discharge sediment. The average level of environmental radiation dose around Seoul Research Reactor was almost same level compared with the past years, and Be-7 and Cs-137 were detected in some surface soil and discharge sediment by {gamma}-spectrometry. (author)

  5. Environmental radiation monitoring around the nuclear facilities

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Woo; Choi, Young Ho; Lee, M.H. [and others

    1999-02-01

    Environmental radiation monitoring was carried out with measurement of environment radiation and environmental radioactivity analysis around KAERI nuclear facilities and Seoul research reactor. The results of environmental radiation monitoring around KAERI nuclear facilities and Seoul research reactor are the follows : The average level of environmental radiation dose measured by NaI scintillation counter and accumulated radiation dose by TLD was almost same level compared with the past years. Gross {alpha}, {beta} radioactivity in environmental samples showed a environmental level. {gamma}-radionuclides in water samples were not detected. But only radionuclide K-40, which is natural radionuclide, was detected in the all samples and Cs-137 was detected in the surface soil and discharge sediment. The average level of environmental radiation dose around Seoul research reactor was almost same level compared with the past years, and Be-7 and Cs-137 were detected in some surface soil and discharge sediment by {gamma}-spectrometry. (author). 3 refs., 50 tabs., 12 figs.

  6. Environmental radiation monitoring around the nuclear facilities

    International Nuclear Information System (INIS)

    Lee, Chang Woo; Choi, Geun Sik and others

    2001-02-01

    Environmental Radiation Monitoring was carried out with measurement of environment. Radiation and environmental radioactivity analysis around KAERI nuclear facilities and Seoul Research Reactor. The results of environmental radiation monitoring around KAERI nuclear facilities and Seoul Research Reactor are the follows : The average level of environmental radiation dose measured by NaI scintillation counter and accumulated radiation dose by TLD was almost same level compared with the past years. Gross α, β radioactivity in environmental samples showed a environmental level. γ-radionuclides in water samples were not detected. But only radionuclide K-40, which is natural radionuclide, was detected in the all samples and Cs-137 was detected in the surface soil and discharge sediment. The average level of environmental radiation dose around Seoul Research Reactor was almost same level compared with the past years, and Be-7 and Cs-137 were detected in some surface soil and discharge sediment by γ-spectrometry

  7. Growth mechanism of NaClO 3 and NaBrO 3 crystals from aqueous ...

    Indian Academy of Sciences (India)

    A study of growth rates of NaClO3 and NaBrO3 has been carried out using a small growth cell by in situ observation. Normal growth rates of {100} faces of NaClO3 and {111} faces of NaBrO3 along ⟨ 110 ⟩ direction are measured under relatively high supersaturation ranging from 3–8%. In the initial stages of growth, {100}, ...

  8. Location of leakages in the fresh water primary network distribution in the Nuclear Center

    International Nuclear Information System (INIS)

    Rodriguez, A.G.; Perez, G.V.; Rodriguez, A.F.

    1992-01-01

    In the hydraulic net of Nuclear Centre in Salazar, Mexico was necessary the application of radioactive traces after very much efforts for locating the situation of leaks of water and not obtain satisfactory results for other methods. It was injected a small quantity of 24 Na 2 CO 3 in aqueous solution in the tank discharge which stores the fresh water. After the running water movement was followed for gamma radiation detection omitted by the 24 Na in grave digged each 100 meters along the pipes. In this work is presented the methodology used to locate two water leaks and the corresponding safety radiological considerations. (Author)

  9. Porous glass with high silica content for nuclear waste storage : preparation, characterization and leaching

    International Nuclear Information System (INIS)

    Aegerter, M.A.; Santos, D.I. dos; Ventura, P.C.S.

    1984-01-01

    Aqueous solutions simulating radioactive nuclear wastes (like Savanah River Laboratory) were incorporated in porous glass matrix with high silica content prepared by decomposition of borosilicate glass like Na 2 O - B 2 O 3 - SiO 2 . After sintering, the samples were submitted, during 28 days, to standard leaching tests MCC1, MCC5 (Soxhlet) and stagnating. The total weight loss, ph, as well as the integral and differential leaching rates and the accumulated concentrations in the leach of Si, Na, B, Ca, Mn, Al, Fe and Ni. The results are compared with the results from reference borosilicate glass, made by fusion, ceramic, synroc, concrets, etc... (E.G.) [pt

  10. Rescue of Na+ affinity in aspartate 928 mutants of Na+,K+-ATPase by secondary mutation of glutamate 314.

    Science.gov (United States)

    Holm, Rikke; Einholm, Anja P; Andersen, Jens P; Vilsen, Bente

    2015-04-10

    The Na(+),K(+)-ATPase binds Na(+) at three transport sites denoted I, II, and III, of which site III is Na(+)-specific and suggested to be the first occupied in the cooperative binding process activating phosphorylation from ATP. Here we demonstrate that the asparagine substitution of the aspartate associated with site III found in patients with rapid-onset dystonia parkinsonism or alternating hemiplegia of childhood causes a dramatic reduction of Na(+) affinity in the α1-, α2-, and α3-isoforms of Na(+),K(+)-ATPase, whereas other substitutions of this aspartate are much less disruptive. This is likely due to interference by the amide function of the asparagine side chain with Na(+)-coordinating residues in site III. Remarkably, the Na(+) affinity of site III aspartate to asparagine and alanine mutants is rescued by second-site mutation of a glutamate in the extracellular part of the fourth transmembrane helix, distant to site III. This gain-of-function mutation works without recovery of the lost cooperativity and selectivity of Na(+) binding and does not affect the E1-E2 conformational equilibrium or the maximum phosphorylation rate. Hence, the rescue of Na(+) affinity is likely intrinsic to the Na(+) binding pocket, and the underlying mechanism could be a tightening of Na(+) binding at Na(+) site II, possibly via movement of transmembrane helix four. The second-site mutation also improves Na(+),K(+) pump function in intact cells. Rescue of Na(+) affinity and Na(+) and K(+) transport by second-site mutation is unique in the history of Na(+),K(+)-ATPase and points to new possibilities for treatment of neurological patients carrying Na(+),K(+)-ATPase mutations. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Experimental cross-sections of deuteron-induced reaction on Y-89 up to 20 MeV; comparison of Ti-nat(d,x)V-48 and Al-27(d,x)Na-24 monitor reactions

    Czech Academy of Sciences Publication Activity Database

    Lebeda, Ondřej; Štursa, Jan; Ráliš, Jan

    2015-01-01

    Roč. 360, OCT (2015), s. 118-128 ISSN 0168-583X R&D Projects: GA MŠk LM2011019 Institutional support: RVO:61389005 Keywords : deuteron-induced nuclear reactions * excitation functions * Na, Mg, Sc, V, Sr, Y and Zr radioisotopes * deuteron beam monitors * U-120M cyclotron Subject RIV: BG - Nuclear , Atomic and Molecular Physics, Colliders Impact factor: 1.389, year: 2015

  12. The system NaVO3-Na2WO4-Na2W2O7

    International Nuclear Information System (INIS)

    Kazanbekov, V.R.; Gasanaliev, A.M.; Kazanbekov, R.G.

    1994-01-01

    Phase diagrams of sodium metavanadate-sodium ditungstate, sodium metavanadate-sodium tungstate systems and surface of primary crystallization of sodium metavabadate-sodium tungstate-sodium ditungstate system were studied. The system sodium metavanadate-sodium ditungstate is eutectic one. Compound NaVO 3 x2Na 2 WO 4 is formed in solid state in sodium metavanadate-sodium tungstate system. Liquidus surface of sodium metavanadate-sodium tungstate-sodium ditungstate is presented by three crystallization fields of initial components. Composition and melting point of ternary eutectics are determined

  13. Summer sudden Na number density enhancements measured with the ALOMAR Weber Na Lidar

    Directory of Open Access Journals (Sweden)

    D. Heinrich

    2008-05-01

    Full Text Available We present summer Na-densities and atmospheric temperatures measured 80 to 110 km above the Arctic Lidar Observatory for Middle Atmosphere Research (ALOMAR. The Weber Na Lidar is part of ALOMAR, located at 69° N in Norway, 150 km north of the Arctic Circle. The sun does not set here during the summer months, and measurements require a narrowband Faraday Anomalous Dispersion Optical Filter (FADOF.

    We discuss an observed sudden enhancement in the Na number density around 22:00 UT on 1 to 2 June 2006. We compare this observation with previous summer measurements and find a frequent appearance of Na number density enhancements near local midnight. We describe the time of appearance, the altitude distribution, the duration and the strength of these enhancements and compare them to winter observations. We investigate possible formation mechanisms and, as others before, we find a strong link between these Na number density enhancements and sporadic E layers.

  14. Summer sudden Na number density enhancements measured with the ALOMAR Weber Na Lidar

    Directory of Open Access Journals (Sweden)

    D. Heinrich

    2008-05-01

    Full Text Available We present summer Na-densities and atmospheric temperatures measured 80 to 110 km above the Arctic Lidar Observatory for Middle Atmosphere Research (ALOMAR. The Weber Na Lidar is part of ALOMAR, located at 69° N in Norway, 150 km north of the Arctic Circle. The sun does not set here during the summer months, and measurements require a narrowband Faraday Anomalous Dispersion Optical Filter (FADOF. We discuss an observed sudden enhancement in the Na number density around 22:00 UT on 1 to 2 June 2006. We compare this observation with previous summer measurements and find a frequent appearance of Na number density enhancements near local midnight. We describe the time of appearance, the altitude distribution, the duration and the strength of these enhancements and compare them to winter observations. We investigate possible formation mechanisms and, as others before, we find a strong link between these Na number density enhancements and sporadic E layers.

  15. Matrizes elétricas na economia mundial: um estudo sobre os posicionamentos na Alemanha, Estados Unidos e China

    Directory of Open Access Journals (Sweden)

    Fabricio Quadros Borges

    2013-11-01

    Full Text Available O objetivo deste trabalho é o de analisar o posicionamento estratégico dos governos na Alemanha, Estados Unidos e China em relação as suas matrizes elétricas. Diante da necessidade de segurança energética, das questões ambientais e de aspectos competitivos estes governos desenvolveram tentativas de transformar estrategicamente o uso de fontes de energia para a geração de eletricidade. Neste sentido, a investigação pretende questionar quais as diretrizes adotadas por estes governos ao reposicionarem suas matrizes elétricas. A metodologia realizou uma coleta de dados a partir de literatura especializada e de documentos que identificaram medidas governamentais pertinentes à construção de novas matrizes elétrica nestes países, de maneira a observar suas diretrizes no processo de formulação destas. O estudo constatou que os três governos procuraram fundamentar suas estratégias na combinação entre recursos disponíveis e fontes sustentáveis para a geração de eletricidade. A Alemanha, através da ampliação da participação da energia eólica, o estado americado da Califórnia, a partir do aumento da proporção utilizada da energia solar, e a China, através da ampliação da participação das fontes: hídrica, nuclear e gás natural, comporam a análise.

  16. Caracterização mecânica e estudo do perfil térmico na soldagem por fricção rotativa de materiais dissimilares

    OpenAIRE

    Eder Paduan Alves

    2016-01-01

    Na busca de processos alternativos utilizados para união de materiais dissimilares, destaca-se o processo de soldagem por fricção rotativa (Rotary Friction Welding), utilizado em tecnologia de ponta na indústria aeroespacial, aeronáutica, nuclear, bélica e automotiva. O processo de soldagem por fricção rotativa (SFR) acontece no estado sólido sem ocorrência de fusão entre as partes, e apresenta como principais mecanismos a difusão e mistura mecânica. Este trabalho tem como objetivo a caracter...

  17. A comparative study of functional properties of normal and wooden breast broiler chicken meat with NaCl addition.

    Science.gov (United States)

    Xing, Tong; Zhao, Xue; Han, Minyi; Cai, Linlin; Deng, Shaolin; Zhou, Guanghong; Xu, Xinglian

    2017-09-01

    The selection of broilers for augmented growth rate and breast has brought about wooden-breast (WB) muscle abnormalities, which caused substantial economic losses. The objective of this study was to compare water holding capacity, water mobility and distribution, salt-soluble protein (SSP) content, and protein profiles of normal and WB chicken meat with different additions of NaCl. Thirty WB and 30 normal chicken breasts were selected from a deboning line of a major Chinese processing plant at 2 to 3 h post mortem. Two different meat batters were formulated to 150 mg/g meat protein and different NaCl contents (0%, 1%, 2%, 3%, and 4%). Results indicated that as NaCl contents increased, the cooking loss of meat batters decreased (P meat showed different protein profiles, with myosin heavy chain exhibiting a higher intensity at ≥3% salt level. Low-field nuclear magnetic resonance (LF-NMR)revealed an increased T22 and higher P22 in raw WB meat compared to normal meat (P meat batters, WB meat batters had reduced T21 and lower immobilized water proportions at low NaCl contents (meat gels. Meat gels prepared from WB had a lower proportion of water within the myofibrillar protein matrix and a greater proportion of exuded bulk water at NaCl contents meat, meat batters and gels, water distribution and mobility of WB exhibited significant differences compared to normal meat. The addition of NaCl affected water mobility and distributions in meat batters, with a level of 3% NaCl eliminating the differences between processed normal and WB meat products. © 2017 Poultry Science Association Inc.

  18. Muziki wa Hip Hop na Haki Za Kijamii: Dhima, Changamoto na ...

    African Journals Online (AJOL)

    Ni dhahiri kuwa haki za kijamii zinaweza kuwasilishwa kwa jamii pana kupitia sanaa ya hip hop. Makala haya basi, yanabainisha dhima na mchango wa muziki wa hip hop katika masuala ya haki za kijamii, yanafafanua changamoto za muziki huu katika kuwasilisha haki za kijamii na kutoa mapendekezo kwa makundi ...

  19. Sequential growth of sandwiched NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb core–shell–shell nanoparticles for photodynamic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Huang-Yong; Ding, Bin-Bin; Ma, Yin-Chu [Department of Medical Materials and Rehabilitation Engineering, School of Medical Engineering, Hefei University of Technology, Hefei 230009 (China); Sun, Shi-Qi [State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu 730046 (China); Tao, Wei [Department of Medical Materials and Rehabilitation Engineering, School of Medical Engineering, Hefei University of Technology, Hefei 230009 (China); Guo, Yan-Chuan [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Guo, Hui-Chen, E-mail: ghch-2004@hotmail.com [State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu 730046 (China); Yang, Xian-Zhu, E-mail: yangxz@hftu.edu.cn [Department of Medical Materials and Rehabilitation Engineering, School of Medical Engineering, Hefei University of Technology, Hefei 230009 (China); Qian, Hai-Sheng, E-mail: shqian@hfut.edu.cn [Department of Medical Materials and Rehabilitation Engineering, School of Medical Engineering, Hefei University of Technology, Hefei 230009 (China)

    2015-12-01

    Graphical abstract: The monodisperse elliptical NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb core–shell–shell nanoparticles have been synthesized successfully by a facile sequential growth process, which can be used as transducer for photodynamic therapy of cancer cells. - Highlights: • The NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb nanoparticles have been fabricated successfully. • The as-prepared nanoparticles show strong fluorescence excited at 980 or 808 nm. • The nanoparticles were transferred into the aqueous phase via a facile process. • Photosensitizers were loaded into the composites for photodynamic therapy. - Abstract: Upconversion (UC) nanostructures have attracted much interest for their extensive biological applications. In this work, we describe a sequential synthetic route to prepare sandwiched NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb core–shell upconversion nanoparticles. The as-prepared products were investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM, JEM 2100F), respectively. The as-prepared core–shell nanoparticles of NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb are composed of elliptical nanoparticles with a length of 80 nm and width of 42 nm, which show efficient upconversion fluorescence excited at 808 nm indicating the formation of core–shell–shell sandwiched nanostructures. In addition, the as-prepared sandwiched NaYF{sub 4}:Yb/Er@NaYF{sub 4}:Yb@NaNdF{sub 4}:Yb core–shell upconversion nanoparticles also show strong upconversion fluorescence excited at 980 nm. Amphiphilic mPEG{sub 2k}-b-PEBEP{sub 6K} copolymers (denoted as PPE) were chosen to transfer these hydrophobic UCNPs into the aqueous phase for biological application. In vitro photodynamic therapy of cancer cells show that the viability of cells incubated with the nanoparticles loaded with MC 540 was significantly lower as compared to the nanoparticles without photosensitizers exposed to NIR laser.

  20. Intracellular Na+ regulation of Na+ pump sites in cultured vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Allen, J.C.; Navran, S.S.; Seidel, C.L.; Dennison, D.K.; Amann, J.M.; Jemelka, S.K.

    1989-01-01

    Enzymatically dispersed cells from canine saphenous vein and femoral artery were grown in fetal calf serum and studied at day 0 (freshly dispersed) through confluence in primary culture. Intracellular Na levels (Nai), but not intracellular K (Ki), were increased after 24 h in culture and then decreased to a steady state by 4 days. Na+ pump site number [( 3 H] ouabain binding) increased through day 3 and remained elevated. Nai was still elevated at 2 days when the Na+ pump site number began to increase. Total pump turnover (maximum ouabain-inhibited 86 Rb uptake) reflected the increase in Na+ pump site number. These key events precede the observed increases in both protein production and cellular proliferation. If the same cells are maintained in defined medium, without fetal calf serum, Nai, Ki, and the number of [ 3 H]ouabain binding sites do not change with time. These data are consistent with the suggestion that the initial mitogenic response of vascular smooth muscle cells to fetal calf serum involves an increased Na+ influx, and a Nai accumulation, caused by low Na+ pump density. The synthesis of new pump sites effects a decrease in the accumulated Nai, which may be related to cell proliferation

  1. Nuclear Astrophysics Data from Radioactive Beam Facilities. Final report

    International Nuclear Information System (INIS)

    Chen, Alan A.

    2008-01-01

    The scientific aims of this project have been the evaluation and dissemination of key nuclear reactions in nuclear astrophysics, with a focus on ones to be studied at new radioactive beam facilities worldwide. These aims were maintained during the entire funding period from 2003 - 2006. In the following, a summary of the reactions evaluated during this period is provided. Year 1 (2003-04): 21 Na(p,γ) 22 Mg and 18 Ne(α,p) 21 Na - The importance of the 21 Na(p,γ) 22 Mg and the 18 Ne(α,p) 21 Na reactions in models of exploding stars has been well documented: the first is connected to the production of the radioisotope 22 Na in nova nucleosynthesis, while the second is a key bridge between the Hot-CNO cycles and the rp-process in X-ray bursts. By the end of Summer 2004, our group had updated these reaction rates to include all published data up to September 2004, and cast the reaction rates into standard analytical and tabular formats with the assistance of Oak Ridge National Laboratory's computational infrastructure for reaction rates. Since September 2004, ongoing experiments on these two reactions have been completed, with our group's participation in both: 21 Na(p,γ) 22 Mg at the TRIUMF-ISAC laboratory (DRAGON collaboration), and 18Ne(α,p) 21 Na at Argonne National Laboratory (collaboration with Ernst Rehm, Argonne). The data from the former was subsequently published and included in our evaluation. Publication from the latter still awaits independent confirmation of the experimental results. Year 2 (2004-05): The 25Al(p,γ) 26 Si and 13 N(p,γ)14O reactions - For Year 2, we worked on evaluations of the 25 Al(p,γ) 26 Si and 13 N(p,γ) 14 O reactions, in accordance with our proposed deliverables and following similar standard procedures to those used in Year 1. The 25 Al(p,γ) 26 Si reaction is a key uncertainty in the understanding the origin of galactic 26 Al, a target radioisotope for gamma ray astronomy; the 13 N(p,γ) 14 O reaction in turn is the trigger

  2. Viabilidade económica da implementação de um reactor nuclear para a produção de energia eléctrica em Portugal

    OpenAIRE

    Pedro, Miguel António de Morais

    2012-01-01

    O presente trabalho tem como objectivo avaliar economicamente e determinar a viabilidade da implementação de um reactor nuclear para produção de energia eléctrica. Faz-se uma abordagem a aspectos da energia nuclear no mundo e em particular a energia nuclear na união europeia, faz-se uma análise sobre a estrutura do sector nuclear em Espanha e o futuro da energia no mundo. É realizada uma análise sobre a energia nuclear em Portugal, são abordados aspectos como o planeamento energético, a local...

  3. On the Stability of NaO2 in Na-O2 Batteries.

    Science.gov (United States)

    Liu, Chenjuan; Carboni, Marco; Brant, William R; Pan, Ruijun; Hedman, Jonas; Zhu, Jiefang; Gustafsson, Torbjörn; Younesi, Reza

    2018-04-25

    Na-O 2 batteries are regarded as promising candidates for energy storage. They have higher energy efficiency, rate capability, and chemical reversibility than Li-O 2 batteries; in addition, sodium is cheaper and more abundant compared to lithium. However, inconsistent observations and instability of discharge products have inhibited the understanding of the working mechanism of this technology. In this work, we have investigated a number of factors that influence the stability of the discharge products. By means of in operando powder X-ray diffraction study, the influence of oxygen, sodium anode, salt, solvent, and carbon cathode were investigated. The Na metal anode and an ether-based solvent are the main factors that lead to the instability and decomposition of NaO 2 in the cell environment. This fundamental insight brings new information on the working mechanism of Na-O 2 batteries.

  4. Angiotensin II-induced hypertension increases plasma membrane Na pump activity by enhancing Na entry in rat thick ascending limbs.

    Science.gov (United States)

    Gonzalez-Vicente, Agustin; Garvin, Jeffrey L

    2013-11-01

    Thick ascending limbs (TAL) reabsorb 30% of the filtered NaCl load. Na enters the cells via apical Na-K-2Cl cotransporters and Na/H exchangers and exits via basolateral Na pumps. Chronic angiotensin II (ANG II) infusion increases net TAL Na transport and Na apical entry; however, little is known about its effects on the basolateral Na pump. We hypothesized that in rat TALs Na pump activity is enhanced by ANG II-infusion, a model of ANG II-induced hypertension. Rats were infused with 200 ng·kg(-1)·min(-1) ANG II or vehicle for 7 days, and TAL suspensions were obtained. We studied plasma membrane Na pump activity by measuring changes in 1) intracellular Na (Nai) induced by ouabain; and 2) ouabain-sensitive oxygen consumption (QO2). We found that the ouabain-sensitive rise in Nai in TALs from ANG II-infused rats was 12.8 ± 0.4 arbitrary fluorescent units (AFU)·mg(-1)·min(-1) compared with only 9.9 ± 1.1 AFU·mg(-1)·min(-1) in controls (P Na pump expression, the number of Na pumps in the plasma membrane, or the affinity for Na. When furosemide (1.1 mg·kg(-1)·day(-1)) was coinfused with ANG II, no increase in plasma membrane Na pump activity was observed. We concluded that in ANG II-induced hypertension Na pump activity is increased in the plasma membrane of TALs and that this increase is caused by the chronically enhanced Na entry occurring in this model.

  5. Comparison of PVT and NaI(Tl) scintillators for vehicle portal monitor applications

    International Nuclear Information System (INIS)

    Siciliano, E.R.; Ely, J.H.; Kouzes, R.T.; Milbrath, B.D.; Schweppe, J.E.; Stromswold, D.C.

    2005-01-01

    The demand for radiation portal monitor (RPM) systems has increased, and their capabilities are being further scrutinized as they are being applied to the task of detecting nuclear weapons, special nuclear material, and radiation dispersal device materials that could appear at borders. The requirements and constraints on RPM systems deployed at high-volume border crossings are significantly different from those at weapons facilities or steel recycling plants, where RPMs have been historically employed. In this new homeland security application, RPM systems must rapidly detect localized sources of radiation with a very high detection probability and low false-alarm rate, while screening all of the traffic without impeding the flow of commerce. In light of this new Department of Homeland Security application, the capabilities of two popular gamma-ray-detector materials as applied to these needs are re-examined. Both experimental data and computer simulations, together with practical deployment experience, are used to assess currently available polyvinyltoluene and NaI(Tl) gamma-ray detectors for border applications

  6. Estudio comparativo de la frecuencia de micronúcleos y anormalidades nucleares en eritrocitos de tres especies ícticas Comparative studies of the frequency of micronuclei and nuclear abnormalities in erythrocytes of three species fishes

    Directory of Open Access Journals (Sweden)

    Favio E Pollo

    2012-12-01

    Full Text Available Los ecosistemas acuáticos cercanos a las zonas urbanas sufren un deterioro constante ocasionado por diversos factores físico-químicos relacionados con la actividad antrópica, representando un riesgo para los organismos que los habitan, en especial los peces. Estos efectos pueden ser biomonitoreados mediante técnicas de amplia utilización, como el Test de Micronúcleos (Mn y el de Anormalidades nucleares (AN, entre otros. El objetivo de este trabajo fue verifcar y comparar la frecuencia de micronúcleos y anormalidades nucleares en tres especies ícticas colectadas en un lago urbano, Cyprinus carpio, Astyanax eigenmanniorum y Cheirodon interruptus. Luego de la captura y anestesia de los peces, se extrajo de cada individuo una muestra de sangre y se registró el peso y la longitud total. Las muestras fueron fjadas y luego teñidas con Giemsa al 10%, posteriormente se las analizó con microscopio (1000X y se les tomaron fotografías con cámara digital. Se calculó, además, el índice de condición corporal (K para cada uno de los ejemplares capturados. Se aplicó un análisis de correlación de rangos de Spearman (rs entre frecuencia de Mn y AN vs K para cada especie. La prueba de Kruskal-Wallis se aplicó para evaluar diferencias de Mn y AN entre las especies. Los resultados no mostraron una correlación estadísticamente signifcativa (P> 0,05 entre las frecuencias de Mn y AN vs K. Las frecuencias de Mn entre las diferentes especies no arrojaron diferencias signifcativas (P> 0,05, mientras que las AN sí (PAquatic ecosystems near urban areas suffer a steady deterioration caused by physical and chemical factors related to human activity, representing a danger to organisms that inhabit them, especially the fsh. These effects may be biomonitored by widely used techniques, such as the Micronucleus Test (Mn and Nuclear Abnormalities (NA, among others. The aim of this study was to verify and compare the frequency of micronuclei and nuclear

  7. Silicene for Na-ion battery applications

    KAUST Repository

    Zhu, Jiajie

    2016-08-19

    Na-ion batteries are promising candidates to replace Li-ion batteries in large scale applications because of the advantages in natural abundance and cost of Na. Silicene has potential as the anode in Li-ion batteries but so far has not received attention with respect to Na-ion batteries. In this context, freestanding silicene, a graphene-silicene-graphene heterostructure, and a graphene-silicene superlattice are investigated for possible application in Na-ion batteries, using first-principles calculations. The calculated Na capacities of 954mAh/g for freestanding silicene and 730mAh/g for the graphenesilicene superlattice (10% biaxial tensile strain) are highly competitive and potentials of >0.3 V against the Na/Na potential exceed the corresponding value of graphite. In addition, the diffusion barriers are predicted to be <0.3 eV.

  8. Hydrolysis of Rice Straw Pretreated by Na2SO3 Over Fe-resin/NaCl

    Directory of Open Access Journals (Sweden)

    YANG Hui

    2017-05-01

    Full Text Available To increase the conversion of rice straw(RS and the yield of products, we employed three methods, which were ultrasonic wave, steam explosion and Na2SO3 pretreatment to pretreat RS(the treated RS noted as CS-RS, ZQ-RS and Na2SO3-RS, respectively and found that Na2SO3 treatment was the best pretreatment method based on XRD, SEM, elemental analysis and content of cellulose, hemicellulose and lignin. The conversion of Na2SO3-RS and the yield of total reducing sugar(TRS and levulinic acid(LA were 97.3%, 29.6% and 13.5%, respectively by 10% Fe-resin in 3.3% NaCl solution under 200 ℃.

  9. PRODUÇÃO E COMPARTILHAMENTO DO CONHECIMENTO NUCLEAR: UM ESTUDO DE CASO NO IEN/CNEN

    Directory of Open Access Journals (Sweden)

    Marcia Pires da Luz Bettencourt

    2012-04-01

    Full Text Available O estudo procurou identificar ações que possam contribuir para a produção e compartilhamento de conhecimentos e informações na Divisão de Radiofármacos do Instituto de Engenharia Nuclear da Comissão Nacional de Energia Nuclear (IEN/CNEN. A motivação para a pesquisa foi o risco, identificado em relatórios da área nuclear, de perda de conhecimento nessa área nos últimos anos. A gestão do conhecimento foi escolhida como ferramenta para o estudo do problema apontado, por possuir metodologias que visam estimular o processo de produção e compartilhamento de conhecimentos e informações, em empresas privadas e também em instituições públicas, como é o caso do IEN/CNEN. A gestão do conhecimento é uma disciplina relativamente nova, que mesmo não tendo nascido na Ciência da Informação, nela vem buscando sustentação teórica e legitimidade. A pesquisa identifica fatores que influenciam no compartilhamento de informação e conhecimento, tais como: redes sociais, comunidades de prática, ambientes facilitadores de colaboração, cultura organizacional, aprendizagem para formação de competências, e narrativas (storytelling. A revisão da literatura e analise dos dados obtidos, diversas práticas foram identificadas, e foram feitas algumas sugestões. Conclui-se que o estímulo institucional à colaboração e à troca de conhecimentos pode influenciar em resultados positivos em relação a um incremento na produção de novos conhecimentos.

  10. Scanning electron microscope investigations of nuclear pore filters in polyester foils

    International Nuclear Information System (INIS)

    Hopfe, J.

    1980-01-01

    In order to understand and characterize the action of nuclear pore filters it is necessary to know their surface, as well as their bulk, structure. In the present work, investigations of the surface structure (pore size, pore density, pore distribution) and of the pore geometry, especially in the bulk of the filters, are carried out by scanning electron microscopic (SEM) studies. The preparation technique needed is liquid-nitrogen freeze-fracturing followed by a conductive-coating step. Nuclear pore filters studied in this paper were produced by a track etching technique. Laboratory specimens were obtained by bombarding 10 μm thick polyester foils with Xe-ions and a subsequent etching with 20% NaOH. The SEM results are shown and discussed. (author)

  11. Na+/H+ and Na+/NH4+ exchange activities of zebrafish NHE3b expressed in Xenopus oocytes

    Science.gov (United States)

    Ito, Yusuke; Kato, Akira; Hirata, Taku; Hirose, Shigehisa

    2014-01-01

    Zebrafish Na+/H+ exchanger 3b (zNHE3b) is highly expressed in the apical membrane of ionocytes where Na+ is absorbed from ion-poor fresh water against a concentration gradient. Much in vivo data indicated that zNHE3b is involved in Na+ absorption but not leakage. However, zNHE3b-mediated Na+ absorption has not been thermodynamically explained, and zNHE3b activity has not been measured. To address this issue, we overexpressed zNHE3b in Xenopus oocytes and characterized its activity by electrophysiology. Exposure of zNHE3b oocytes to Na+-free media resulted in significant decrease in intracellular pH (pHi) and intracellular Na+ activity (aNai). aNai increased significantly when the cytoplasm was acidified by media containing CO2-HCO3− or butyrate. Activity of zNHE3b was inhibited by amiloride or 5-ethylisopropyl amiloride (EIPA). Although the activity was accompanied by a large hyperpolarization of ∼50 mV, voltage-clamp experiments showed that Na+/H+ exchange activity of zNHE3b is electroneutral. Exposure of zNHE3b oocytes to medium containing NH3/NH4+ resulted in significant decreases in pHi and aNai and significant increase in intracellular NH4+ activity, indicating that zNHE3b mediates the Na+/NH4+ exchange. In low-Na+ (0.5 mM) media, zNHE3b oocytes maintained aNai of 1.3 mM, and Na+-influx was observed when pHi was decreased by media containing CO2-HCO3− or butyrate. These results provide thermodynamic evidence that zNHE3b mediates Na+ absorption from ion-poor fresh water by its Na+/H+ and Na+/NH4+ exchange activities. PMID:24401990

  12. Development of geopolymers as candidate materials for low/intermediate level highly alkaline nuclear waste

    International Nuclear Information System (INIS)

    Perera, D.S.; Vance, E.R.; Kiyama, S.; Aly, Z.; Yee, P.

    2006-01-01

    Full text: Geopolymers have been studied for many years as a possible improvement on cement in respect of compressive strength, resistance to fire, heat and acidity, and as a medium for the encapsulation of hazardous or low/ intermediate level radioactive waste. They are made by adding aluminosilicates to concentrated alkali solutions and the application of heat at 0 Cfor subsequent polymerisation. In this work we studied them as suitable candidate materials to incorporate NaOH/NaA10 2 containing waste with low levels of Cs, Sr and Nd. Geopolymers were produced by incorporating the highly alkaline solution as part of the composition with added metakaolinite, fumed silica and extra NaOH, such that the overall geopolymer composition was of molar ratios Si/Al = 2 and Na/Al = 1. The simulated waste contained Na2SO 4 , therefore Ba(OH) 2 was also added to precipitate the SO 4 x 2 as BaSO 4 . Three geoplymers of the same composition containing simulated wastes were leach tested in triplicate after heating at 400 0 Cfor 1 h (to remove -98% of free and interstitial water) under the PCT-B test protocol at 90 0 Cfor 7 days and their results are listed in Table 1. The Cs, Sr and Nd normalised leach rates were low. The Na leach rate was ∼ 4 g/L thus passing the PCT-B test protocol value of 13.5 g/L for EA glass. The X-ray diffraction and scanning electron microscopy showed that BaS04 did precipitate, however all the S did not appear to have precipitated. The ANSI/ANS-16.1-2003 test was carried out on the above geopolymer composition for 5 days. The ANSI Leachability Index D (diffusivity of 10''cm sec'') for the elements released are listed in Table 2. A Portland cement was also tested for comparison and the Leachability index values are 11, 8 and 10 for Al, Na and Ca respectively. Both passed the test protocol insofar as they were > 6. Geopolymers thus passing the tests for high level nuclear waste glass (PCT-B) and for low level nuclear waste (ANSI) show promising potential

  13. Overview of CNES-CEA joint programme on space nuclear Brayton systems

    International Nuclear Information System (INIS)

    Carre, F.; Proust, E.; Chaudourne, S.; Keirle, P.; Tilliette, Z.; Vrillon, B.

    1990-01-01

    In 1982, a cooperative programme on space nuclear power systems was initiated between the French Centre National d'Etudes Spatiales (CNES) and the Commissariat a l'Energie Atomique (CEA), to assess the feasibility, lead time, cost, competitiveness and development prospects for space nuclear power systems (SPS) in the 20 to 200 kWe range. The present three-year study phase is primarily oriented toward the assessment of various reactor candidate technologies and system design options for nuclear SPS in the 20 kWe class, which corresponds to the expected power needs of the first European space missions, anticipated to begin in 2005. This paper presents an overview of the present programme phase, with emphasis on design studies of three reference design concepts for 20 kWe turboelectric nuclear power systems selected so as to cover a wide range of reactor temperatures and corresponding technologies. The systems differ mainly in their nuclear reactors which are: the Liquid Metal Fast Breeder derivative or UO 2 /Na/Stainless steel -650 0 C; the High Temperature Gas-cooled derivative or UO 2 /direct cycle/super alloys - 850 0 C; and the UN/Li/MoRe alloy - 1120 0 C. All three systems use a Brayton cycle with recuperation for power conversion. (author)

  14. Preparation of the Nuclear Matrix for Parallel Microscopy and Biochemical Analyses.

    Science.gov (United States)

    Wilson, Rosemary H C; Hesketh, Emma L; Coverley, Dawn

    2016-01-04

    Immobilized proteins within the nucleus are usually identified by treating cells with detergent. The detergent-resistant fraction is often assumed to be chromatin and is described as such in many studies. However, this fraction consists of both chromatin-bound and nuclear-matrix-bound proteins. To investigate nuclear-matrix-bound proteins alone, further separation of these fractions is required; the DNA must be removed so that the remaining proteins can be compared with those from untreated cells. This protocol uses a nonionic detergent (Triton X-100) to remove membranes and soluble proteins from cells under physiologically relevant salt concentrations, followed by extraction with 0.5 m NaCl, digestion with DNase I, and removal of fragmented DNA. It uses a specialized buffer (cytoskeletal buffer) to stabilize the cytoskeleton and nuclear matrix in relatively gentle conditions. Nuclear matrix proteins can then be assessed by either immunofluorescence (IF) and immunoblotting (IB). IB has the advantage of resolving different forms of a protein of interest, and the soluble fractions can be analyzed. The major advantage of IF analysis is that individual cells (rather than homogenized populations) can be monitored, and the spatial arrangement of proteins bound to residual nuclear structures can be revealed. © 2016 Cold Spring Harbor Laboratory Press.

  15. The relation between aging, aortic NaF avidity and coronary artery NaF avidity: A NaF PET CT study

    DEFF Research Database (Denmark)

    Blomberg, Björn; Thomassen, Anders; Hildebrandt, Malene

    2013-01-01

    volunteers without traditional cardiovascular risk factors were prospectively assessed by Sodium 18-Fluoride (Na-18F) PET CT imaging. Global aortic uptake of Na-18F was determined by calculating the average aortic blood pool subtracted maximum standardized uptake value (cSUV) [maximum SUVaorta - mean...

  16. Rescue of Na+ and H+ binding in Na+,K+-ATPase M8 aspartate mutants by secondary mutation

    DEFF Research Database (Denmark)

    Holm, Rikke; Einholm, Anja P.; Andersen, Jens Peter

    A mutation replacing the aspartate in transmembrane segment M8 in the a3-isoform of Na,K-ATPase with asparagine has been found in patients with rapid-onset dystonia parkinsonism or alternating hemiplegia of childhood. This aspartate may be a critical Na+ coordinating residue, but the crystal......-isoforms of Na,K-ATPase, and much smaller effects were seen for other mutations to the M8 aspartate, which were less disruptive of Na+ binding than mutations to other residues related to Na+ site III. The D928 (rat a1 numbering) mutations strongly diminished the cooperativity of Na+ binding. Moreover the p......H optimum of Na,K-ATPase activity was left-shifted, again with D928N being most disruptive. The reduced affinity for activating Na+ and for inhibitory protons, caused by D928N and D928A mutations, could be rescued by introduction of an additional mutation of a glutamate located far away from D928....

  17. Salinity tolerance in barley (hordeum vulgare l.): effects of varying NaCl, K/sup +/ Na/sup +/ and NaHCO/sub 3/ levels on cultivars differing in tolerance

    International Nuclear Information System (INIS)

    Mahmood, K.

    2011-01-01

    Although barley (Hordeum vulgare L.) is regarded as salt tolerant among crop plants, its growth and plant development is severely affected by ionic and osmotic stresses in salt-affected soils. To elucidate the tolerance mechanism, growth and ion uptake of three barley cultivars, differing in salt tolerance, were examined under different levels of NaCl, K/sup +/ Na/sup +/ and NaHCO/sub 3/ in the root medium. The cultivars differed greatly in their responses to varying root medium conditions. Plant growth was more adversely affected by NaHCO/sub 3/ than NaCl. In general, biomass yields were comparable under control and 100 mM NaCl. However, growth of all three cultivars was significantly inhibited by NaHCO/sub 3/ even at low concentration (10 mM). Improved K/sup +/ supply in saline medium increased K/sup +/ uptake and growth of less tolerant cultivars. K/sup +/ uptake was more adversely affected by NaHCO/sub 3/ than NaCl salinity. Selective K/sup +/ uptake and lower Cl/sup -/ in shoots seemed to be associated with the growth responses. K application would help better growth of these cultivars on K-deficient saline-sodic soils and under irrigation with poor quality water having high Residual Sodium Carbonate (RSC) and/or Sodium Adsorption Ratio (SAR). (author)

  18. Dose evaluation on the basis of 24Na activity in the human body for the criticality accident at JCO Tokai nuclear fuel processing plant

    International Nuclear Information System (INIS)

    Momose, T.; Tsujimura, N.; Tasaki, T.; Kanai, K.; Hayashi, N.; Shinohara, K.

    2001-01-01

    24 Na in the human body, activated by neutrons emitted at the JCO criticality accident, was observed for 62 subjects, where 148 subjects were measured by the whole body counter of JNC Tokai Works. The 148 subjects, including JCO employees and the contractors, residents neighboring the site and emergency service officers, were measured by the whole-body counter. The neutron-energy spectrum around the facility was calculated using neutron transport codes (ANISN and MCNP), and the relation between an amount of activated sodium in human body and neutron dose was evaluated from the calculated neutron energy spectrum and theoretical neutron capture probability by the human body. The maximum 24 Na activity in the body was 7.7 kBq (83 Bq( 24 Na)/g( 23 Na)) and the relevant effective dose equivalent was 47 mSv. (author)

  19. Glutathionylation-Dependence of Na+-K+-Pump Currents Can Mimic Reduced Subsarcolemmal Na+ Diffusion

    OpenAIRE

    Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald?J.; Rasmussen, Helge?H.

    2016-01-01

    The existence of a subsarcolemmal space with restricted diffusion for Na+ in cardiac myocytes has been inferred from a transient peak electrogenic Na+-K+ pump current beyond steady state on reexposure of myocytes to K+ after a period of exposure to K+-free extracellular solution. The transient peak current is attributed to enhanced electrogenic pumping of Na+ that accumulated in the diffusion-restricted space during pump inhibition in K+-free extracellular solution. However, there are no know...

  20. Homogeneity of peraluminous SiO2-B2O3-Al2O3-Na2O-CaO-Nd2O3 glasses: Effect of neodymium content

    International Nuclear Information System (INIS)

    Gasnier, E.; Bardez-Giboire, I.; Massoni, N.; Montouillout, V.; Pellerin, N.; Allix, M.; Ory, S.; Cabie, M.; Poissonnet, S.; Massiot, D.

    2014-01-01

    Considering the interest of developing new glass matrices able to immobilize higher concentration of high level nuclear wastes than currently used nuclear borosilicate compositions, glasses containing high rare earth contents are of particular interest. This study focuses on a peraluminous alumino borosilicate system SiO 2 -B 2 O 3 -Al 2 O 3 -Na 2 O-CaO-Nd 2 O 3 defined by a per-alkaline/peraluminous ratio RP = ([Na 2 O] + [CaO])/ ([Na 2 O] + [CaO] + [Al 2 O 3 ]) ≤ 0.5. Samples with various contents of Nd 2 O 3 from 0 to 10 mol% were studied using DSC, XRD, SEM, TEM, STEM and EMPA methods. The glasses present a high thermal stability even after a slow cooling treatment from the melt. Only a slight mullite crystallization is detected for low Nd 2 O 3 content (≤2.3 mol%) and crystallization of a neodymium borosilicate crystalline phase combined to a phase separation occurred at high Nd 2 O 3 content (≥8 mol%). The solubility of neodymium in the presence of aluminum is demonstrated, with higher neodymium incorporation amounts than in per-alkaline glasses. (authors)

  1. Myocardial Na,K-ATPase: Clinical aspects

    OpenAIRE

    Kjeldsen, Keld

    2003-01-01

    The specific binding of digitalis glycosides to Na,K-ATPase is used as a tool for Na,K-ATPase quantification with high accuracy and precision. In myocardial biopsies from patients with heart failure, total Na,K-ATPase concentration is decreased by around 40%; a correlation exists between a decrease in heart function and a decrease in Na,K-ATPase concentration. During digitalization, around 30% of remaining pumps are occupied by digoxin. Myocardial Na,K-ATPase is also influenced by other drugs...

  2. Down-Regulation of the Na+-Coupled Phosphate Transporter NaPi-IIa by AMP-Activated Protein Kinase

    Directory of Open Access Journals (Sweden)

    Miribane Dërmaku-Sopjani

    2013-11-01

    Full Text Available Background/Aims: The Na+-coupled phosphate transporter NaPi-IIa is the main carrier accomplishing renal tubular phosphate reabsorption. It is driven by the electrochemical Na+ gradient across the apical cell membrane, which is maintained by Na+ extrusion across the basolateral cell membrane through the Na+/K+ ATPase. The operation of NaPi-IIa thus requires energy in order to avoid cellular Na+ accumulation and K+ loss with eventual decrease of cell membrane potential, Cl- entry and cell swelling. Upon energy depletion, early inhibition of Na+-coupled transport processes may delay cell swelling and thus foster cell survival. Energy depletion is sensed by the AMP-activated protein kinase (AMPK, a serine/threonine kinase stimulating several cellular mechanisms increasing energy production and limiting energy utilization. The present study explored whether AMPK influences the activity of NAPi-IIa. Methods: cRNA encoding NAPi-IIa was injected into Xenopus oocytes with or without additional expression of wild-type AMPK (AMPKα1-HA+AMPKβ1-Flag+AMPKγ1-HA, of inactive AMPKαK45R (AMPKα1K45R+AMPKβ1-Flag+AMPKγ1-HA or of constitutively active AMPKγR70Q (AMPKα1-HA+AMPKβ1-Flag+AMPKγ1R70Q. NaPi-IIa activity was estimated from phosphate-induced current in dual electrode voltage clamp experiments. Results: In NaPi-IIa-expressing, but not in water-injected Xenopus oocytes, the addition of phosphate (1 mM to the extracellular bath solution generated a current (Ip, which was significantly decreased by coexpression of wild-type AMPK and of AMPKγR70Q but not of AMPKαK45R. The phosphate-induced current in NaPi-IIa- and AMPK-expressing Xenopus ooocytes was significantly increased by AMPK inhibitor Compound C (20 µM. Kinetic analysis revealed that AMPK significantly decreased the maximal transport rate. Conclusion: The AMP-activated protein kinase AMPK is a powerful regulator of NaPi-IIa and thus of renal tubular phosphate transport.

  3. Construction of a remote probe for a spectrometer using NaI(TI) detector and X-ray fluorescence by energy dispersion

    International Nuclear Information System (INIS)

    Brandão Junior, Francisco Antônio

    2014-01-01

    This research project aims the utilization of NaI(Tl) cylindrical detectors with different sensitive volumes in the Nuclear Instrumentation Laboratory (LIN) of the Department of Nuclear Engineering at UFMG (DEN-UFMG) for construction of spectrometers using the X-ray fluorescence (XRF) technique. Conical coupling devices between the crystal detectors and the photomultiplier valve (VMF) were designed and constructed using easily handled material, joined by an optical fiber cable (FO) for driving the luminescence from the detector crystal to the VFM, allowing greater flexibility and accessibility to the device using the aforementioned technique. The cable connections were adapted to the cones that have a system with adjustable convergent lens to maximize level of luminescence (input and output). The photon beam is conducted by FO from the crystal detector to the VFM. This remote probe may bring new solutions for use not only in EDXRF technique but also in other future applications using the NaI(Tl) detector. The SR was designed and built based on the FO properties to conduct the light by total reflection with minimal loss; the first SR qualitative tests were performed and the results demonstrate that the system works properly. (author)

  4. A P2-Type Layered Superionic Conductor Ga-Doped Na2 Zn2 TeO6 for All-Solid-State Sodium-Ion Batteries.

    Science.gov (United States)

    Li, Yuyu; Deng, Zhi; Peng, Jian; Chen, Enyi; Yu, Yao; Li, Xiang; Luo, Jiahuan; Huang, Yangyang; Zhu, Jinlong; Fang, Chun; Li, Qing; Han, Jiantao; Huang, Yunhui

    2018-01-24

    Here, a P2-type layered Na 2 Zn 2 TeO 6 (NZTO) is reported with a high Na + ion conductivity ≈0.6×10 -3  S cm -1 at room temperature (RT), which is comparable to the currently best Na 1+n Zr 2 Si n P 3-n O 12 NASICON structure. As small amounts of Ga 3+ substitutes for Zn 2+ , more Na + vacancies are introduced in the interlayer gaps, which greatly reduces strong Na + -Na + coulomb interactions. Ga-substituted NZTO exhibits a superionic conductivity of ≈1.1×10 -3  S cm -1 at RT, and excellent phase and electrochemical stability. All solid-state batteries have been successfully assembled with a capacity of ≈70 mAh g -1 over 10 cycles with a rate of 0.2 C at 80 °C. 23 Na nuclear magnetic resonance (NMR) studies on powder samples show intra-grain (bulk) diffusion coefficients D NMR on the order of 12.35×10 -12  m 2  s -1 at 65 °C that corresponds to a conductivity σ NMR of 8.16×10 -3  S cm -1 , assuming the Nernst-Einstein equation, which thus suggests a new perspective of fast Na + ion conductor for advanced sodium ion batteries. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Activity of NaOH buffered by silicate solids in molten sodium acetate-water at 3170C

    International Nuclear Information System (INIS)

    Weres, O.; Tsao, L.

    1988-01-01

    Silica and sodium acetate are present in the steam generator tube sheet crevices of many nuclear power plants. Trace solutes in the condensate are tremendously concentrated in the crevices by boiling. Sparingly soluble sodium silicates and other solids precipitate from the crevice liquid leaving an extremely concentrated molten mixture of water, sodium acetate and other salts. The precipitates buffer the activity of sodium hydroxide in the superheated liquid that remains. The activity of NaOH corresponding to the buffers quartz/sodium disilicate and sodium disilicate/sodium metasilicate at 317 0 C has been determined experimentally. The sodium hydroxide content of a sodium acetate-water melt buffered by these reactions was determined by chemical analysis, and the corresponding activity of NaOH at temperature was calculated using the recently published Pitzer-Simonson Model of molten salt-water mixtures. The molten mixture of sodium acetate and water plays the role solvent in these experiments and calculations. The free energies of formation of solid sodium silicates at 317 0 C were also determined. The activity of NaOH corresponding to other silicate and phosphate buffers was calculated using published thermodynamic data and estimated from phase diagrams

  6. Direct characterization of cotton fabrics treated with di-epoxide by nuclear magnetic resonance.

    Science.gov (United States)

    Xiao, Min; Chéry, Joronia; Keresztes, Ivan; Zax, David B; Frey, Margaret W

    2017-10-15

    A non-acid-based, di-functional epoxide, neopentyl glycol diglycidyl ether (NPGDGE), was used to modify cotton fabrics. Direct characterization of the modified cotton was conducted by Nuclear Magnetic Resonance (NMR) without grinding the fabric into a fine powder. NaOH and MgBr 2 were compared in catalyzing the reaction between the epoxide groups of NPGDGE and the hydroxyl groups of cellulose. Possible reaction routes were discussed. Scanning electron microscopy (SEM) images showed that while the MgBr 2 -catalyzed reaction resulted in self-polymerization of NPGDGE, the NaOH-catalyzed reaction did not. Fourier transform infrared spectroscopy (FTIR) showed that at high NaOH concentration cellulose restructures from allomorph I to II. NMR studies verified the incorporation of NPGDGE into cotton fabrics with a clear NMR signal, and confirmed that at higher NaOH concentration the efficiency of grafting of NPGDGE was increased. This demonstrates that use of solid state NMR directly on woven fabric samples can simultaneously characterize chemical modification and crystalline polymorph of cotton. No loss of tensile strength was observed for cotton fabrics modified with NPGDGE. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Securing a better future for all: Nuclear techniques for global development and environmental protection. NA factsheet on nuclear sciences and applications collaborating centres: Establishing a culture of cooperation

    International Nuclear Information System (INIS)

    2012-01-01

    As a large international organization with a variety of programmes, initiatives and laboratories, one of the mandates of the IAEA is to promote the peaceful use of nuclear techniques worldwide while also collaborating with other institutions in its Member States in order to implement part of its approved activities. In this regard, the IAEA designates selected institutions as official IAEA collaborating centres (IAEA-CCs). Recognizing the need to preserve and transfer nuclear knowledge, the IAEA-CCs are dedicated to furthering the research, development and training in peaceful applications of nuclear science and technology. By working alongside various nuclear related institutions from around the world, the IAEA contributes to reaching important targets laid out by the United Nations Millennium Development Goals. The IAEA-CCs are, in general, scientific institutions such as laboratories, universities, research facilities, etc., that receive public recognition by the IAEA and have been designated to collaborate with the IAEA in a variety of fields, such as food safety, environmental protection, water resources and human health. In line with the objectives of the IAEA, IAEA-CCs are expected to further the research, development and training in the peaceful applications of nuclear science and technology. Through these research and academic institutions, Member States can assist the IAEA with their own original research, development and training in nuclear technologies. As a cooperative mechanism, the IAEA-CC is also efficient, as it encourages centres to share resources, knowledge and expertise. One of the goals of the IAEA-CC is also to help developing Member States expand their capabilities in these areas and thus improve the quality of life of their citizens. So far, the IAEA-CC has led to socioeconomic benefits in many parts of the world, from Asia to Latin America.

  8. Thermodynamic study of NaFe complex oxides. High temperature properties of Na sub 5 FeO sub 4 and Na sub 3 FeO sub 3

    CERN Document Server

    Furukawa, T

    2002-01-01

    In order to contribute the investigation into corrosion mechanism of the structural materials by leakage sodium, thermodynamic study of Na-Fe complex oxides formed by the reactions was carried out. Na sub 5 FeO sub 4 and Na sub 3 FeO sub 3 were used as the sample. Its high temperature properties (i.e. melting, solidification and transformation) were observed by Differential Scanning Calorimetry, DSC. Moreover, the original test named 'melting point confirmation test' was performed for the observation of traces of melting and solidification after the tests. Following contents have been obtained by this study. (1) Na sub 5 FeO sub 4 was stably as the solid without phase transformation and melting until 800degC. However, the compound was showing a tendency to change into Na sub 4 FeO sub 3 with temperature increasing under the low oxygen potential. (2) The stability of Na sub 3 FeO sub 3 is the same as that of Na sub 5 FeO sub 4 until 700degC. Over the temperature, the compound was changed differential compound ...

  9. Metallic Na formation in NaCl crystals with irradiation of electron or vacuum ultraviolet photon

    Energy Technology Data Exchange (ETDEWEB)

    Owaki, Shigehiro [Osaka Prefecture Univ., Sakai, Osaka (Japan). Coll. of Integrated Arts and Sciences; Koyama, Shigeko; Takahashi, Masao; Kamada, Masao; Suzuki, Ryouichi

    1997-03-01

    Metallic Na was formed in NaCl single crystals with irradiation of a variety of radiation sources and analyzed the physical states with several methods. In the case of irradiation of 21 MeV electron pulses to the crystal blocks, the optical absorption and lifetime measurement of positron annihilation indicated appearance of Na clusters inside. Radiation effects of electron beam of 30 keV to the crystals in vacuum showed the appearance of not only metallic Na but atomic one during irradiation with Auger electron spectroscopy. Intense photon fluxes in vacuum ultraviolet region of synchrotron radiation were used as another source and an analyzing method of ultraviolet photoelectron spectroscopy. The results showed the metallic Na layered so thick that bulk plasmon can exist. (author)

  10. WE-H-207A-04: Impact of Lesion Location On the Repeatability of 18F-NaF PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Lin, C; Perk, T; Harmon, S; Perlman, S; Liu, G; Jeraj, R [University of Wisconsin, Madison, WI (United States)

    2016-06-15

    Purpose: Quantifying the repeatability of imaging biomarkers is critical for assessing therapeutic response. While {sup 18}F-NaF PET/CT has shown to be a repeatable imaging method, research has not shown which factors may influence its repeatability. The purpose of this study was to evaluate whether the location of the lesion impacts the repeatability of quantitative {sup 18}F-NaF PET-derived SUV metrics. Methods: Metastatic castrate-resistant prostate cancer patients with multiple bone lesions received whole-body test-retest NaF PET/CT scans. Malignant bone lesions of PET-defined volume greater than 1.5 cm{sup 3} were identified by a nuclear medicine physician and automatically delineated using a SUV>15 threshold. The maximum (SUVmax), average (SUVmean), and total (SUVtotal) SUV were extracted from each lesion. Atlas-based segmentation was used to divide each patient skeleton into 25 skeletal regions. Test-retest repeatability of each SUV metric was assessed with coefficient of variation (CV). Results: A total of 265 malignant bone lesions from 18 patients were identified by nuclear medicine physician. The largest proportion of bone lesions were localized to the spine (41%), with 41% of those lesions localized to the thoracic spine. One-way ANOVA showed that measurement differences differed significantly for all three metrics across locations (p<0.01 for each metrics). Overall, CV was smallest for SUVmean at 5.3%, followed by SUVmax at 11.5% and SUVtotal at 20.4%. Lesions in the pubis were consistently the most repeatable (CV(SUVmax)= 5.6%, CV(SUVmean)= 0.6%, CV(SUVtotal)= 2.9%). According to SUVmean, repeatability was poorest in the cervical spine (CV = 6.2%), whereas according to SUVmax and SUVtotal, repeatability was poorest in the ribs (CV(SUVmax)= 15.0%, CV(SUVtotal)= 29.8%). Conclusion: Location of the lesion affects the repeatability of {sup 18}F-NaF PET/CT, with the ribs and cervical spine having the lowest repeatability and the pubis having the highest

  11. Effect of paclitaxel (Taxol) on the biodistribution of sodium pertechnetate (Na99mTcO4) in female Wistar rats

    Energy Technology Data Exchange (ETDEWEB)

    Holanda, Cecilia Maria de Carvalho Xavier; Oliveira, Elias Herculano de; Rocha, Louisianny Guerra da [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Microbiologia e Parasitologia. Lab. de Ensaios Antiparasitarios e de Radiobiologia Experimental]. E-mail: cechol@ufrnet.br; Barbosa, Vanessa Santos de Arruda [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Centro de Ciencias da Saude; Spyrides, Maria Helena Constantino [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Estatistica; Aragao, Cicero Flavio Soares [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Dept. de Farmacia; Medeiros, Aldo da Cunha [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Hospital Universitario Onofre Lopes

    2008-12-15

    The evidence that natural or synthetic drugs can affect the biodistribution of radiopharmaceuticals (radiobiocomplexes) in setting of nuclear medicine clinic is already known. We studied the effect of Paclitaxel, an anti-neoplastic agent for the treatment of solid tumors, on the biodistribution of Na{sup 99}'mTcO{sub 4} in female rats. Paclitaxel (1 mg/mL/week) was administered into animals in single dose during 3 weeks, with interval of 1 week among them. The control group received NaCl 0.9% solutions by the same via. One hour after the last dose, it was injected Na{sup 99m}TcO{sub 4} in the animals. The percentage of activity per gram (%ATI/g) and biochemical and hematological determinations were performed. A significant increase were found in alanine aminotransferase, aspartate aminotransferase, glucose and in the %ATI/g of some organs (ovaries, uterus, vagina, breasts, large intestine and liver). These results can be associated, probably, to the capacity of paclitaxel to alter the biodistribution of Na{sup 99m}TcO{sub 4} and the metabolism of glucose and hepatic enzymes. (author)

  12. Impacts of the turbogenerator reactive operation in the nuclear fuel burnup; Impactos da operacao reativa do turbogerador na queima do combustivel nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Helio Ricardo V. de; Martinez, Aquilino S. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Nuclear

    2002-07-01

    The parameterization of the losses in a turbogenerator in function of an operation with the electrical system reactive allowed to model in a simple and exact way the equations that define and they quantify the additional of nuclear potency that it should be generated by a reactor, in order to maintain the commitment with the national system operator, that is, the electric active power contracted. starting from this additional of nuclear power it was modeled the additional burn up of the fuel elements, as well as the numbers of effective days to full power wasted. it was promoted a safety analysis and some limitations due to the reactive operation of the electrical system. inside of this context it was made a financial evaluation in which we ask some questions to companies and government organs in order to define what losses are acceptable and also the reason why we don't use other technician resources such as: increase of the electrical mesh, electrical power injection in strategic points, capacitor banks and increase of the number the electrical plants. (author)

  13. Supporting the President's Arms Control and Nonproliferation Agenda: Transparency and Verification for Nuclear Arms Reductions

    International Nuclear Information System (INIS)

    Doyle, James E.; Meek, Elizabeth

    2009-01-01

    The President's arms control and nonproliferation agenda is still evolving and the details of initiatives supporting it remain undefined. This means that DOE, NNSA, NA-20, NA-24 and the national laboratories can help define the agenda, and the policies and the initiatives to support it. This will require effective internal and interagency coordination. The arms control and nonproliferation agenda is broad and includes the path-breaking goal of creating conditions for the elimination of nuclear weapons. Responsibility for various elements of the agenda will be widely scattered across the interagency. Therefore an interagency mapping exercise should be performed to identify the key points of engagement within NNSA and other agencies for creating effective policy coordination mechanisms. These can include informal networks, working groups, coordinating committees, interagency task forces, etc. It will be important for NA-20 and NA-24 to get a seat at the table and a functional role in many of these coordinating bodies. The arms control and nonproliferation agenda comprises both mature and developing policy initiatives. The more mature elements such as CTBT ratification and a follow-on strategic nuclear arms treaty with Russia have defined milestones. However, recent press reports indicate that even the START follow-on strategic arms pact that is planned to be complete by the end of 2009 may take significantly longer and be more expansive in scope. The Russians called for proposals to count non-deployed as well as deployed warheads. Other elements of the agenda such as FMCT, future bilateral nuclear arms reductions following a START follow-on treaty, nuclear posture changes, preparations for an international nuclear security summit, strengthened international safeguards and multilateral verification are in much earlier stages of development. For this reason any survey of arms control capabilities within the USG should be structured to address potential needs across the

  14. O projeto do submarino nuclear brasileiro The Brazilian nuclear submarine project

    Directory of Open Access Journals (Sweden)

    João Roberto Martins Filho

    2011-12-01

    Full Text Available O artigo procura reconstruir a trajetória do programa do submarino nuclear brasileiro desde suas origens, no governo Geisel, aos dias atuais. Lançando mão do conceito de oportunismo tecnológico, procura analisar a atitude dos diferentes governos federais sobre o projeto, mostrando que os governos neoliberais de Fernando Collor, Itamar Franco e Fernando Henrique Cardoso cortaram radicalmente verbas para o programa, sem, no entanto, suspendê-lo por completo. Surpreendentemente, parece haver uma continuidade entre os governos militares e o governo Lula, quanto ao apoio decidido à ideia do submarino nuclear. Quanto às relações de força na Marinha, o texto conclui que não há divergências significativas sobre a relevância do programa, o que não exclui choques de personalidades navais, em virtude do caráter autárquico assumido pelo projeto e da dificuldade de continuá-lo apenas com verbas da própria força. O artigo utilizou entrevistas recentes com atores-chaves do processo.The article aims to reconstruct the history of the Brazilian nuclear-powered submarine program, from its origins to the present. Using the concept of technological opportunism, it seeks to understand the position of the different federal administrations vis-à-vis the project, concluding that the Collor, Franco and Cardoso administrations did not support the program. However, they did not terminate the project. Surprisingly, there is a continuity between the military governments and the Lula administration, in the decisive support each gave to the program. With repect to the Navy, the analysis concludes that there were no significant disagreements, with the exception of personal conflicts originating in the autarchic features that the program had assumed and in the problem of scarcity of resources. The article is based on interviews with key actors.

  15. Synthesis of Ag or Pt Nanoparticles by Hydrolysis of Either Ag2Na or PtNa

    Directory of Open Access Journals (Sweden)

    Huabin Wang

    2008-01-01

    Full Text Available Ag and Pt nanoparticles have successfully been synthesized by hydrolysis of either Ag2Na or PtNa at room temperature. The oxidation of sodium in the Pt-Na pellets was much faster than that in the Ag-Na pellets since Pt is a catalyst for H2O formation reaction from hydrogen and oxygen at room temperature. The hydrolysis byproduct, NaOH, has a high solubility and easily is removed. This method offers a simple method of preparing transition metal nanoparticles. The Ag and Pt nanoparticles prepared by this method were crystalline in nature, and spherical in shape with a mean size of around 10 nm.

  16. Dynamic polarizabilities and Van der Waals coefficients for alkali atoms Li, Na and alkali dimer molecules Li2, Na2 and NaLi

    Science.gov (United States)

    Mérawa, M.; Dargelos, A.

    1998-07-01

    The present paper gives an account of investigations of the polarizability of the alkali atoms Li, Na, diatomics homonuclear and heteronuclear Li2, Na2 and NaLi at SCF (Self Consistent Field) level of approximation and at correlated level, using a time Time-Dependent Gauge Invariant method (TDGI). Our static polarizability values agree with the best experimental and theoretical determinations. The Van der Waals C6 coefficients for the atom-atom, atom-dimer and dimer-dimer interactions have been evaluated. Les polarisabilités des atomes alcalins Li, Na, et des molécules diatomiques homonucléaires et hétéronucléaire Li2, Na2 et NaLi, ont été calculées au niveau SCF (Self Consistent Field) et au niveau corrélé à partir d'une méthode invariante de jauge dépendante du temps(TDGI). Nos valeurs des polarisabilités statiques sont en accord avec les meilleurs déterminations expérimentales et théoriques. Les coefficients C6 de Van de Waals pour les interactions atome-atome, atome-dimère et dimère-dimère ont également été évalués.

  17. Structure-function relationships of Na+, K+, ATP, or Mg2+ binding and energy transduction in Na,K-ATPase

    DEFF Research Database (Denmark)

    Jorgensen, Peter L.; Pedersen, Per Amstrup

    2000-01-01

    Na,K-ATPase; Mutagenesis; Na+ binding; K+ binding; Tl+ binding; Mg2+ binding; ATP binding; Cation binding site; Energy transduction......Na,K-ATPase; Mutagenesis; Na+ binding; K+ binding; Tl+ binding; Mg2+ binding; ATP binding; Cation binding site; Energy transduction...

  18. At NA2

    CERN Multimedia

    1977-01-01

    One of the NA2 calorimeter sections is moved in. The NA2 calorimeter was divided in two halves, to the left and the right of the beam, each half consisting of sheets of passive high Z material interleaved with blades of plastic scintillators. The photo shows on the right, the upstream 'electron' module with eleven lead plates for a total radiation length of 20.

  19. Leaching studies of heavy concrete material for nuclear fuel waste immobilization containers

    International Nuclear Information System (INIS)

    Onofrei, M.; Raine, D.; Brown, L.; Hooton, R.D.

    1989-08-01

    The leaching behaviour of a high-density concrete was studied as part of a program to evaluate its potential use as a container material for nuclear fuel waste under conditions of deep geologic disposal. Samples of concrete material were leached in deionized distilled water, Standard Canadian Shield Saline Solution (SCSSS), SCSSS plus 20% Na-bentonite, and SCSSS plus granite and 20% Na-bentonite under static conditions at 100 degrees celsius for periods up to 365 days. The results of these leaching experiments suggest that the stability of concrete depends on the possible internal structural changes due to hydration reactions of unhydrated components, leading to the formation of C-S-H gel plus portlandite (Ca(OH) 2 ). The factors controlling the concrete leaching process were the composition of the leachant and the concentration of elements in solution capable of forming precipitates on the concrete surface, e.g., silicon, Mg 2+ and Ca 2+ . The main effect observed during leaching was an increase in groundwater pH (from 7 to 9). However, the addition of Na-bentonite suppressed the normal tendency of the pH of the groundwater in contact with concrete to rise rapidly. It was shown that the solution concentration of elements released from the concrete, particularly potassium, increased in the presence of Na-bentonite

  20. Na+-K+ pump in chronic renal failure

    International Nuclear Information System (INIS)

    Deepak, K.; Kahn, T.

    1987-01-01

    This review summarizes the evidence for the defect in Na + -K + pump in chronic renal failure, considers the role of various factors in causing this defect, and discusses the clinical implications thereof. Intracellular Na is elevated in erythrocytes, leukocytes, and muscle cells from some patients with chronic renal failure (CRF). Recent evidence suggest that this elevation of cell Na may be, in large part, a consequence of decreased number of Na + -K + pump units per cell. Maintenance dialysis over a period of weeks ameliorates the defect in intracellular Na + , and this improvement is contemporaneous with an increase in the number of Na + -K + pump sites per cell. In erythrocytes with normal cell Na + , acute hemodialysis increases the rate of 22 Na + and 42 K + transport. Many factors such as the presence of retained toxic metabolite or circulating inhibitor in the uremic plasma, or biochemical changes produced by acute hemodialysis, may explain this finding. In cells with high cell Na + , the pump-mediated 42 K + transport is normalized at the expense of a raised cell Na + . The decreased muscle membrane potential in uremic subjects has been attributed to a decreased activity of Na + -K + pump. The authors discuss the role of hormonal abnormalities and circulating inhibitors, which may cause an acute inhibition of the pump and of other factors such as K + depletion, which may cause more chronic alterations. The implications of alteration of Na + and K + pump transport and raised cell Na + on other non-pump-mediated transport pathways are discussed. Raised cell Na + may be a marker for the adequacy of maintenance dialysis in patients with end-stage renal failure

  1. Pozitivni in negativni vplivi risank na otroke

    OpenAIRE

    Povše, Nika

    2017-01-01

    V tej diplomski nalogi smo raziskovali pozitivne in negativne vplive risank na otroke. Začeli smo z zgodovino televizije, tako svetovno zgodovino kot zgodovino televizije na Slovenskem. Na isti način smo pregledali tudi zgodovino risank. Raziskovali smo otrokov razvoj, predvsem tiste vidike, ki so izpostavljeni vplivom risank, kot so morala, jezik, domišljija in učenje. Sledilo je raziskovanje negativnih in pozitivnih vplivov, ki jih imajo risanke na otroke, kar je tudi naš glavni problem te ...

  2. Vpliv konfucija na sodobno izobraževanje na Kitajskem

    Directory of Open Access Journals (Sweden)

    Katja Skitek

    2009-12-01

    Full Text Available Izobraževanje na Kitajskem je bilo vedno trdno povezano s Konfucijem in konfucianizmom, kar pa ni čudno, saj je bil Konfucij prvi, ki je poudarjal moč z nanja in izobraževanja. LR Kitajska je v zadnjih petdesetih letih počasi in postopoma začela uveljavljati določene spremembe v vzgojno-izobraževalni sistem. Kakšne so te spremembe in koliko nanje še vedno vpliva konfucianizem, bo osrednja tema pričujočega članka. Konfucianizem danes na Kitajskem ni preveč popularen, izobraženci pa so se razporedili v dve skupini: eni trdijo, da je njegov vpliv še vedno velik, drugi pa zatrjujejo, da nima več nobenega vpliva na sodobno življenje. Katera stran ima prav? Konfucij je v prvi vrsti poudarjal pomembnost moralnih vrednot vsakega človeka in prav moralne vrednote, za katere se je zavzemal, so še danes trdno zasidrane v kitajski kulturi. Ali je torej sploh mogoče popolnoma izriniti Konfucija iz sodobnega izobraževanja?

  3. Low-spin states of 23Na

    International Nuclear Information System (INIS)

    Bakkum, E.L.

    1987-01-01

    A study of 23 Na via the 22 Ne(p,γ) 23 Na and 23 Na(γ,γ) 23 Na reactions is presented. Only a limited number of resonances has been studied, selected on the basis of strong excitation of the lowest levels of which the spin was unknown. As a result the spins are now known of all levels of 23 Na with excitation energies up to 7 MeV, except for a few high-spin states which are too weakly excited in the decay of the known 22 Ne(p,γ) resonances. The mean lifetimes of the 23 Na levels at 4.43 and 7.89 MeV were found to be 350±70 and 220±17 attoseconds (1 attosecond = 10 -18 seconds) respectively. 97 refs.; 22 figs.; 12 tabs

  4. Waste processing system for nuclear power plant

    International Nuclear Information System (INIS)

    Higashinakagawa, Emiko; Tezuka, Fuminobu; Maesawa, Yukishige; Irie, Hiromitsu; Daibu, Etsuji.

    1996-01-01

    The present invention concerns a waste processing system of a nuclear power plant, which can reduce the volume of a large amount of plastics without burying them. Among burnable wastes and plastic wastes to be discarded in the power plant located on the sea side, the plastic wastes are heated and converted into oils, and the burnable wastes are burnt using the oils as a fuel. The system is based on the finding that the presence of Na 2 O, K 2 O contained in the wastes catalytically improves the efficiency of thermal decomposition in a heating atmosphere, in the method of heating plastics and converting them into oils. (T.M.)

  5. Nuclear dynamics in the metastable phase of the solid acid caesium hydrogen sulfate.

    Science.gov (United States)

    Krzystyniak, Maciej; Drużbicki, Kacper; Fernandez-Alonso, Felix

    2015-12-14

    High-resolution spectroscopic measurements using thermal and epithermal neutrons and first-principles calculations within the framework of density-functional theory are used to investigate the nuclear dynamics of light and heavy species in the metastable phase of caesium hydrogen sulfate. Within the generalised-gradient approximation, extensive calculations show that both 'standard' and 'hard' formulations of the Perdew-Burke-Ernzerhof functional supplemented by Tkatchenko-Scheffler dispersion corrections provide an excellent description of the known structure, underlying vibrational density of states, and nuclear momentum distributions measured at 10 and 300 K. Encouraged by the agreement between experiment and computational predictions, we provide a quantitative appraisal of the quantum contributions to nuclear motions in this solid acid. From this analysis, we find that only the heavier caesium atoms reach the classical limit at room temperature. Contrary to naïve expectation, sulfur exhibits a more pronounced quantum character relative to classical predictions than the lighter oxygen atom. We interpret this hitherto unexplored nuclear quantum effect as arising from the tighter binding environment of this species in this technologically relevant material.

  6. Response of saliva Na/K ratio to changing Na supply of lactating cows under tropical conditions

    NARCIS (Netherlands)

    Thiangtum, Wandee; Schonewille, J Thomas; Verstegen, Martin Wa; Arsawakulsudhi, Supot; Rukkwamsuk, Theera; Hendriks, Wouter H

    BACKGROUND: Factorial determination of the sodium (Na) requirement of heat-stressed lactating cows is hindered by accurate estimates of the Na losses through sweat. Direct studies, therefore, may be needed requiring information on the time course of healthy animals to become Na depleted and the

  7. Response of saliva Na/K ratio to changing Na supply of lactating cows under tropical conditions

    NARCIS (Netherlands)

    Thiangtum, Wandee; Schonewille, Thomas J.; Verstegen, Martin W.A.; Arsawakulsudhi, Supot; Rukkwamsuk, Theera; Hendriks, Wouter H.

    2017-01-01

    BACKGROUND: Factorial determination of the sodium (Na) requirement of heat-stressed lactating cows is hindered by accurate estimates of the Na losses through sweat. Direct studies, therefore, may be needed requiring information on the time course of healthy animals to become Na depleted and the

  8. Clues to NaCN formation

    Science.gov (United States)

    Quintana-Lacaci, G.; Cernicharo, J.; Velilla Prieto, L.; Agúndez, M.; Castro-Carrizo, A.; Fonfría, J. P.; Massalkhi, S.; Pardo, J. R.

    2017-11-01

    Context. ALMA is providing us essential information on where certain molecules form. Observing where these molecules emission arises from, the physical conditions of the gas, and how this relates with the presence of other species allows us to understand the formation of many species, and to significantly improve our knowledge of the chemistry that occurs in the space. Aims: We studied the molecular distribution of NaCN around IRC +10216, a molecule detected previously, but whose origin is not clear. High angular resolution maps allow us to model the abundance distribution of this molecule and check suggested formation paths. Methods: We modeled the emission of NaCN assuming local thermal equilibrium (LTE) conditions. These profiles were fitted to azimuthal averaged intensity profiles to obtain an abundance distribution of NaCN. Results: We found that the presence of NaCN seems compatible with the presence of CN, probably as a result of the photodissociation of HCN, in the inner layers of the ejecta of IRC +10216. However, similar as for CH3CN, current photochemical models fail to reproduce this CN reservoir. We also found that the abundance peak of NaCN appears at a radius of 3 × 1015 cm, approximately where the abundance of NaCl, suggested to be the parent species, starts to decay. However, the abundance ratio shows that the NaCl abundance is lower than that obtained for NaCN. We expect that the LTE assumption might result in NaCN abundances higher than the real ones. Updated photochemical models, collisional rates, and reaction rates are essential to determine the possible paths of the NaCN formation. Based on observations carried out with ALMA and the IRAM 30 m Telescope. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. IRAM is supported by INSU/CNRS (France

  9. Evaluation of genotoxicity in automobile mechanics occupationally exposed to polycyclic aromatic hydrocarbons using micronuclei and other nuclear abnormalities.

    Science.gov (United States)

    Khan, Mohammed Rafiq; Sudha, Sellappa

    2012-01-01

    Occupational and environmental exposures mostly represent mixtures of genotoxic agents, whereas the specificity of biomarker measurements varies widely. Exploration of correlations among biomarkers contributes to the further progress of molecular cancer epidemiology and to the selection of the optimal biomarkers for the investigation of human exposure to carcinogens. The aim of this study was to assess the potential cytogenetic damage associated with occupational exposure to Polycyclic Aromatic Hydrocarbons (PAHs) among automobile mechanics by using Micronuclei (MN) and other Nuclear Abnormalities (NA) as a biomarker. The study population composed of 110 occupationally exposed automobile mechanics and 100 unexposed controls. All the study participants were males. Both the exposed and control individuals were selected from automobile garages located in the urban area of Coimbatore City, South India. Exfoliated buccal cells were collected from 110 automobile mechanics and 100 age and sex matched controls. Further, cells were examined for MN frequency and Nuclear Abnormalities (NA) other than micronuclei, such as binucleates, broken eggs and karyolysis. Results showed a statistically significant difference between occupationally exposed automobile mechanics and control groups. MN and NA frequencies in automobile mechanics were significantly higher than those in control groups (p < 0.05) and also significantly related to smoking habit (p < 0.05). In addition, a higher degree of NA was observed among the exposed subjects with smoking, drinking, tobacco chewing, which is an indicative of cytogenetic damage in these individuals. MN and other NA reflect genetic changes, events associated with carcinogenesis. Therefore, the results of this study indicate that automobile mechanics exposed to PAHs are under risk of significant cytogenetic damage. Therefore, it is important to provide and offer better awareness of occupational hazards among these workers to promote

  10. Charmonia suppression in p-A collisions at 450 GeV/c new results from NA50

    CERN Document Server

    Abreu, M C; Alessandro, B; Alexa, C; Arnaldi, R; Ataian, M R; Baglin, C; Baldit, A; Bedjidian, Marc; Beolè, S; Boldea, V; Bordab, P; Borenstein, S R; Borges, G; Bussière, A; Capelli, L; Castor, J I; Castanier, C; Chaurand, B; Cheynis, B; Chiavassa, E; Cicalò, C; Claudino, T; Comets, M P; Constans, N; Constantinescu, S; Cortese, P; Cruz, J; De Marco, N; De Falco, A; Dellacasa, G; Devaux, A; Dita, S; Drapier, O; Espagnon, B; Fargeix, J; Force, P; Callio, M; Gavrilov, Yu K; Gerschel, C; Giubellino, P; Golubeva, M B; Gonin, M; Grigorian, A A; Grigorian, S; Grossiord, J Y; Guber, F F; Guichard, A; Gulkanian, H R; Hakobyan, R S; Haroutunian, R; Idzik, M; Jouan, D; Karavitcheva, T L; Kluberg, L; Kurepin, A B; Le Bornec, Y; Lourenço, C; Macciotta, P; MacCormick, M; Marzari-Chiesa, A; Masera, M; Masoni, A; Monteno, M; Musso, A; Petiau, P; Piccotti, A; Pizzi, J R; Prado da Silva, W L; Prino, F; Puddu, G; Quintans, C; Ramos, S; Ramello, L; Rato-Mendes, P; Riccati, L; Romana, A; Santos, H; Saturnini, P; Scalas, E; Scomparin, E; Serci, S; Shahoyan, R; Sigaudo, F; Silvar, S; Sitta, M; Sonderegger, P; Tarrago, X; Topilskaya, N S; Usai, G L; Vercellin, Ermanno; Villatte, L; Willis, N

    2002-01-01

    Drell-Yan, J/$\\psi$ and $\\psi^{\\prime}$ production in proton-induced collisions on Be, Al, Cu, Ag and W targets has been studied by the NA50 collaboration at the CERN SPS. Results on absolute cross sections and cross section ratios are presented. We show that J/$\\psi$ suppression in proton-nucleus and in sulphur-uranium collisions can be understood in terms of nuclear absorption and there is no indication of an additional suppression mechanism in S-U collisions compared to p-A. (11 refs).

  11. Charmonia suppression in p-A collisions at 450 GeV/c new results from NA50

    CERN Document Server

    Abreu, M C; Alexa, C; Arnaldi, R; Ataian, M R; Baglin, C; Baldit, A; Bedjidian, Marc; Beolè, S; Boldea, V; Bordab, P; Borenstein, S R; Borges, G; Bussière, A; Capelli, L; Castor, J I; Castanier, C; Chaurand, B; Cheynis, B; Chiavassa, E; Cicalò, C; Claudino, T; Comets, M P; Constans, N; Constantinescu, S; Cortese, P; Cruz, J; De Marco, N; De Falco, A; Dellacasa, G; Devaux, A; Dita, S; Drapier, O; Espagnon, B; Fargeix, J; Force, P; Callio, M; Gavrilov, Yu K; Gerschel, C; Giubellino, P; Golubeva, M B; Gonin, M; Grigorian, A A; Grigorian, S; Grossiord, J Y; Guber, F F; Guichard, A; Gulkanian, H R; Hakobyan, R S; Haroutunian, R; Idzik, M; Jouan, D; Karavitcheva, T L; Kluberg, L; Kurepin, A B; Le Bornec, Y; Lourenço, C; Macciotta, P; MacCormick, M; Marzari-Chiesa, A; Masera, M; Masoni, A; Monteno, M; Musso, A; Petiau, P; Piccotti, A; Pizzi, J R; Prado da Silva, W L; Prino, F; Puddu, G; Quintans, C; Ramos, S; Ramello, L; Rato-Mendes, P; Riccati, L; Romana, A; Santos, H; Saturnini, P; Scalas, E; Scomparin, E; Serci, S; Shahoyan, R; Sigaudo, F; Silvar, S; Sitta, M; Sonderegger, P; Tarrago, X; Topilskaya, N S; Usai, G L; Vercellin, Ermanno; Villatte, L; Willis, N

    2002-01-01

    Drell-Yan, J/ psi and psi ' production in proton-induced collisions on Be, Al, Cu, Ag and W targets has been studied by the NA50 collaboration at the CERN SPS. Results on absolute cross sections and cross section ratios are presented. We show that J/ psi suppression in proton-nucleus and in sulphur-uranium collisions can be understood in terms of nuclear absorption and there is no indication of an additional suppression mechanism in S-U collisions compared to p-A. (11 refs).

  12. A 125Te and 23Na NMR investigation of the structure and crystallisation of sodium tellurite glasses.

    Science.gov (United States)

    Holland, D; Bailey, J; Ward, G; Turner, B; Tierney, P; Dupree, R

    2005-01-01

    125Te static nuclear magnetic resonance (NMR) and 23Na and 125Te magic angle spinning (MAS) NMR have been used, in conjunction with X-ray diffraction, to examine the structure and crystallisation behaviour of glasses of composition xNa2O.(1-x)TeO2 (0.075 x 0.4). The MAS NMR 23Na spectra from the glasses are broad and featureless but shift by approximately +5 ppm with increased x, i.e. as the system becomes more ionic. The static 125Te NMR spectra show an increase in axial symmetry with increasing x, indicating a shift from predominantly [TeO4] to [TeO3] structural units. The 23Na and 125Te spectra from the crystallised samples have been fitted to obtain information on the sites in the metastable crystal phases, which are the first to form on heating and which are therefore more closely related to the glass structure than thermodynamically stable crystal phases. New sodium tellurite phases are reported, including a sodium stabilised, face centred cubic phase related to delta-TeO2; a metastable form of Na2Te4O9 containing 3 sodium and 4 tellurium sites; and a metastable form of Na2Te2O5 containing 2 sodium sites. There is evidence of oxidation of TeIV to TeVI occurring in glasses with high values of x and, at x=0.40 and 0.50 (outside the glass forming range), some sodium metatellurate (Na2TeO4) is formed at the same time as sodium metatellurite (Na2TeO3). The 125Te shift is very sensitive to environment within the sodium tellurite system, covering more than 320 ppm, with anisotropies varying from 640 to 1540 ppm. The lack of features in the 125Te spectra of the glass phases, combined with the large shift range and high but variable anisotropy, means than it is not possible to obtain a unique fit to any presumed species present. Furthermore, the chemical shift anisotropy parameters for three of the four Te sites in the Na2Te4O9 phase are found to lie outside the range used for previous simulations of glass spectra.

  13. Immobilisation of high level nuclear reactor wastes in SYNROC

    Energy Technology Data Exchange (ETDEWEB)

    Ringwood, A E; Kesson, S E; Ware, N G; Hibberson, W; Major, A [Australian National Univ., Canberra. Inst. of Advanced Studies

    1979-03-15

    It is stated that the elements occurring in high-level nuclear reactor wastes can be safely immobilised by incorporating them within the crystal lattices of the constituent minerals of a synthetic rock (SYNROC). The preferred form of SYNROC can accept up to 20% of high level waste calcine to form dilute solid solutions. The constituent minerals, or close structural analogues, have survived in a wide range of geochemical environments for periods of 20 to 2,000 Myr whilst immobilising the same elements present in nuclear wastes. SYNROC is unaffected by leaching for 24 hours in pure water or 10 wt % NaCl solution at high temperatures and pressure whereas borosilicate glasses completely decompose in a few hours in much less severe hydrothermal conditions. The combination of these leaching results with the geological evidence of long-term stability indicates that SYNROC would be vastly superior to glass in its capacity to safely immobilise nuclear wastes, when buried in a suitable geological repository. A dense, compact, mechanically strong form of SYNROC suitable for geological disposal can be produced by a process as economical as that which incorporates radioactive waste in borosilicate glasses.

  14. The effect of Na+ and K+ on the thermal denaturation of Na+ and + K+-dependent ATPase.

    Science.gov (United States)

    Fischer, T H

    1983-01-01

    To increase our understanding of the physical nature of the Na+ and K+ forms of the Na+ + K+-dependent ATPase, thermal-denaturation studies were conducted in different types of ionic media. Thermal-denaturation measurements were performed by measuring the regeneration of ATPase activity after slow pulse exposure to elevated temperatures. Two types of experiments were performed. First, the dependence of the thermal-denaturation rate on Na+ and K+ concentrations was examined. It was found that both cations stabilized the pump protein. Also, K+ was a more effective stabilizer of the native state than was Na+. Secondly, a set of thermodynamic parameters was obtained by measuring the temperature-dependence of the thermal-denaturation rate under three ionic conditions: 60 mM-K+, 150 mM-Na+ and no Na+ or K+. It was found that ion-mediated stabilization of the pump protein was accompanied by substantial increases in activation enthalpy and entropy, the net effect being a less-pronounced increase in activation free energy. PMID:6309139

  15. Fabrication of NaYF4:Yb,Er Nanoprobes for Cell Imaging Directly by Using the Method of Hydrion Rivalry Aided by Ultrasonic.

    Science.gov (United States)

    Li, Zhihua; Miao, Haixia; Fu, Ying; Liu, Yuxiang; Zhang, Ran; Tang, Bo

    2016-12-01

    A novel method of fabricating water-soluble bio-probes with ultra-small size such as NaYF 4 :Yb,Er (18 nm), NaGdF 4 :Yb,Er (8 nm), CaF 2 :Yb,Er (10 nm), PbS (7 nm), and ZnS (12 nm) has been developed to provide for the solubility switch of nanoparticles from oil-soluble to water-soluble in terms of hydrion rivalry aided by ultrasonic. Using NaYF 4 :Yb,Er (18 nm) as an example, we evaluate the properties of as-prepared water-soluble nanoparticles (NPs) by using thermogravimetric analyses (TGA), Fourier transform infrared spectroscopy (FTIR), zeta potential (ζ) testing, and 1H nuclear magnetic resonance ( 1 HNMR). The measured ζ value shows that the newly prepared hydrophilic NaYF 4 :Yb,Er NPs are the positively charged particles. Acting as reactive electrophilic moiety, the freshly prepared hydrophilic NaYF 4 :Yb,Er NPs have carried out the coupling with amino acids and fluorescence labeling and imaging of HeLa cells directly. Experiments indicate that the method of hydrion rivalry aided by ultrasonic provides a simple and novel opportunity to transform hydrophobic NPs into hydrophilic NPs with good reactivity, which can be imaging some specific biological targets directly.

  16. Financiranje projekata na pomorskom dobru

    Directory of Open Access Journals (Sweden)

    Zoran Tasić

    2018-02-01

    Full Text Available Koncesije otvaraju vrlo osjetljiva politička, ekonomska i pravna pitanja u mnogim državama svijeta. Samo definiranje pojma koncesije često je komplicirana i ne sasvim jasna zadaća. OECD je prihvatila definiciju koncesije kao: ’’davanje prava privatnom trgovačkom društvu da može gospodarski upravljati određenom infrastrukturnim uslugama i za to zarađivati naknadu. Koncesionar dobija u posjed određene objekte (ali vlasništvo na tim objektima ostaje u rukama države te ih koristi u svrhu obavljanja određene djelatnosti ili usluge sukladno odredbama ugovora’’. Hrvatsko pravo definira koncesije načelno kao pravo stečeno temeljem ugovora o koncesiji, a sukladno uvjetima sadržanim u odluci o davanju koncesije (koju je donijelo odgovarajuće upravno tijelo, a u odnosu na pomorsko dobro, specifično, kao pravo državne vlasti da može dio pomorskog dobra, koje je inače dobro izvan pravnog prometa (res extra commercium, isključiti iz opće uporabe bilo dijelom ili u cijelosti, i dati ga fizičkoj ili pravnoj osobi na gospodarsko korištenje sukladno određenim prostornim planovima. Građevine i drugi objekti izgrađeni na pomorskom dobru čine njegov sastavni dio. Zakonom je jasno određeno da nikakva stvarna prava nisu dopuštena na pomorskom dobru, uključivo i na objektima izgrađenima na njemu. Projekti na pomorskom dobru često uključuju velike infrastrukturne projekte, razvoje luka i marina, koji iziskuju značajna financijska sredstva. Banke koje financiraju takve projekte zahtijevaju organiziran i transparentan zakonski okvir koncesija, slobodu ugovaranja, pravnu zaštitu svih strana uključenih u projekt (uključivo i mogućnost međunarodne arbitraže. (...

  17. Modelling the local atomic structure of molybdenum in nuclear waste glasses with ab initio molecular dynamics simulations.

    Science.gov (United States)

    Konstantinou, Konstantinos; Sushko, Peter V; Duffy, Dorothy M

    2016-09-21

    The nature of chemical bonding of molybdenum in high level nuclear waste glasses has been elucidated by ab initio molecular dynamics simulations. Two compositions, (SiO 2 ) 57.5 -(B 2 O 3 ) 10 -(Na 2 O) 15 -(CaO) 15 -(MoO 3 ) 2.5 and (SiO 2 ) 57.3 -(B 2 O 3 ) 20 -(Na 2 O) 6.8 -(Li 2 O) 13.4 -(MoO 3 ) 2.5 , were considered in order to investigate the effect of ionic and covalent components on the glass structure and the formation of the crystallisation precursors (Na 2 MoO 4 and CaMoO 4 ). The coordination environments of Mo cations and the corresponding bond lengths calculated from our model are in excellent agreement with experimental observations. The analysis of the first coordination shell reveals two different types of molybdenum host matrix bonds in the lithium sodium borosilicate glass. Based on the structural data and the bond valence model, we demonstrate that the Mo cation can be found in a redox state and the molybdate tetrahedron can be connected with the borosilicate network in a way that inhibits the formation of crystalline molybdates. These results significantly extend our understanding of bonding in Mo-containing nuclear waste glasses and demonstrate that tailoring the glass composition to specific heavy metal constituents can facilitate incorporation of heavy metals at high concentrations.

  18. Controlled phase stability of highly Na-active triclinic structure in nanoscale high-voltage Na2-2xCo1+xP2O7 cathode for Na-ion batteries

    Science.gov (United States)

    Song, Hee Jo; Kim, Jae-Chan; Dar, Mushtaq Ahmad; Kim, Dong-Wan

    2018-02-01

    With the increasing demand for high energy density in energy-storage systems, a high-voltage cathode is essential in rechargeable Li-ion and Na-ion batteries. The operating voltage of a triclinic-polymorph Na2CoP2O7, also known as the rose form, is above 4.0 V (vs. Na/Na+), which is relatively high compared to that of other cathode materials. Thus, it can be employed as a potential high-voltage cathode material in Na-ion batteries. However, it is difficult to synthesize a pure rose phase because of its low phase stability, thus limiting its use in high-voltage applications. Herein, compositional-engineered, rose-phase Na2-2xCo1+xP2O7/C (x = 0, 0.1 and 0.2) nanopowder are prepared using a wet-chemical method. The Na2-2xCo1+xP2O7/C cathode shows high electrochemical reactivity with Na ions at 4.0 V, delivering high capacity and high energy density.

  19. A plunger device for in-beam measurements of nuclear lifetimes

    International Nuclear Information System (INIS)

    Battistuzzi, G.; Dainese, B.; Signorini, C.; Stefanini, A.M.

    1977-01-01

    An experimental apparatus was built to measure life-times of excited nuclear states with the recoil-distance method (RDM). A millesimal micrometer and an electromagnetic gauge-head are used to measure the target-stopper distance, and their parallelism is tested by optical and capacitance methods. Measurements were performed in the nuclei 22 Na and 153 Dy, populated by the reactions 19 F(α, n) and 144 Nd( 12 C, 3n), respectively. A minimum target-stopper distance of approximately 3 μm has been reached. (Auth.)

  20. Optimization of NaOH Molarity, LUSI Mud/Alkaline Activator, and Na2SiO3/NaOH Ratio to Produce Lightweight Aggregate-Based Geopolymer

    Directory of Open Access Journals (Sweden)

    Rafiza Abdul Razak

    2015-05-01

    Full Text Available This paper presents the mechanical function and characterization of an artificial lightweight geopolymer aggregate (ALGA using LUSI (Sidoarjo mud and alkaline activator as source materials. LUSI stands for LU-Lumpur and SI-Sidoarjo, meaning mud from Sidoarjo which erupted near the Banjarpanji-1 exploration well in Sidoarjo, East Java, Indonesia on 27 May 2006. The effect of NaOH molarity, LUSI mud/Alkaline activator (LM/AA ratio, and Na2SiO3/NaOH ratio to the ALGA are investigated at a sintering temperature of 950 °C. The results show that the optimum NaOH molarity found in this study is 12 M due to the highest strength (lowest AIV value of 15.79% with lower water absorption and specific gravity. The optimum LUSI mud/Alkaline activator (LM/AA ratio of 1.7 and the Na2SiO3/NaOH ratio of 0.4 gives the highest strength with AIV value of 15.42% with specific gravity of 1.10 g/cm3 and water absorption of 4.7%. The major synthesized crystalline phases were identified as sodalite, quartz and albite. Scanning Electron Microscope (SEM image showed more complete geopolymer matrix which contributes to highest strength of ALGA produced.

  1. Optimization of NaOH Molarity, LUSI Mud/Alkaline Activator, and Na2SiO3/NaOH Ratio to Produce Lightweight Aggregate-Based Geopolymer

    Science.gov (United States)

    Abdul Razak, Rafiza; Abdullah, Mohd Mustafa Al Bakri; Hussin, Kamarudin; Ismail, Khairul Nizar; Hardjito, Djwantoro; Yahya, Zarina

    2015-01-01

    This paper presents the mechanical function and characterization of an artificial lightweight geopolymer aggregate (ALGA) using LUSI (Sidoarjo mud) and alkaline activator as source materials. LUSI stands for LU-Lumpur and SI-Sidoarjo, meaning mud from Sidoarjo which erupted near the Banjarpanji-1 exploration well in Sidoarjo, East Java, Indonesia on 27 May 2006. The effect of NaOH molarity, LUSI mud/Alkaline activator (LM/AA) ratio, and Na2SiO3/NaOH ratio to the ALGA are investigated at a sintering temperature of 950 °C. The results show that the optimum NaOH molarity found in this study is 12 M due to the highest strength (lowest AIV value) of 15.79% with lower water absorption and specific gravity. The optimum LUSI mud/Alkaline activator (LM/AA) ratio of 1.7 and the Na2SiO3/NaOH ratio of 0.4 gives the highest strength with AIV value of 15.42% with specific gravity of 1.10 g/cm3 and water absorption of 4.7%. The major synthesized crystalline phases were identified as sodalite, quartz and albite. Scanning Electron Microscope (SEM) image showed more complete geopolymer matrix which contributes to highest strength of ALGA produced. PMID:26006238

  2. UTJECAJ POZITIVNE DISKRIMINACIJE NA UKLJUČIVANJE ŽENA NA TRŽIŠTE RADA U REPUBLICI HRVATSKOJ

    OpenAIRE

    Dovranić, Dora; Katavić, Ivica

    2016-01-01

    U početku 21. stoljeća često se koristi pojam pozitivne (afirmativne) diskriminacije. Pozitivna diskriminacija mjera je koju poduzima vlada, neka organizacija ili korporacija s ciljem da se smanje nejednakosti u društvu nastale upravo diskriminacijom, na način da se pružaju određene povlastice onima koji su pretrpjeli neku vrstu diskriminacije. Nastala je u Sjedinjenim Američkim Državama na inicijativu predsjednika Kennedyja, Johnsona i Nixona. Diskriminacija, nažalost, ima mnogo oblika, a ne...

  3. Dose evaluation on the basis of {sup 24}Na activity in the human body for the criticality accident at JCO Tokai nuclear fuel processing plant

    Energy Technology Data Exchange (ETDEWEB)

    Momose, T.; Tsujimura, N.; Tasaki, T.; Kanai, K.; Hayashi, N.; Shinohara, K. [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

    2001-11-01

    {sup 24}Na in the human body, activated by neutrons emitted at the JCO criticality accident, was observed for 62 subjects, where 148 subjects were measured by the whole body counter of JNC Tokai Works. The 148 subjects, including JCO employees and the contractors, residents neighboring the site and emergency service officers, were measured by the whole-body counter. The neutron-energy spectrum around the facility was calculated using neutron transport codes (ANISN and MCNP), and the relation between an amount of activated sodium in human body and neutron dose was evaluated from the calculated neutron energy spectrum and theoretical neutron capture probability by the human body. The maximum {sup 24}Na activity in the body was 7.7 kBq (83 Bq({sup 24}Na)/g({sup 23}Na)) and the relevant effective dose equivalent was 47 mSv. (author)

  4. A comparative neutronic analysis of KALIMER breeder core using Na or Pb-Bi coolant

    International Nuclear Information System (INIS)

    Yoo, J. W.; Kim, S. J.; Kim, Y. I.

    2000-01-01

    A comparative neutronic study has been conducted on KALIMER breeder core according to the replacement of sodium coolant by Pb-Bi coolant. Since the atomic weight of Pb and Bi is about 9 times heavier than that of Na, the energy loss by neutron colliding with Pb-Bi nucleus will be very small. Therefore, the reactor with Pb-Bi coolant will have a harder neutron spectrum than that with Na coolant. Consequently, the breeding ratio and burnup reactivity swing is expected to be enhanced. In addition, when Pb-Bi coolant is voided, a negative coolant void coefficient can be obtained by the net effects of smaller spectrum hardening and large neutron leakage. As a result, the breeding ratio was increased from 1.18 to 1.23 and burnup reactivity swing was reduced from 631 pcm to 150 pcm. When the coolant in the whole region of active core is voided, the coolant void coefficient was found to be -539 and -264 pcm at BOEC and EOEC, respectively. In the local voided case, the smaller coolant void coefficient was obtained than that of Na coolant. Accordingly, the use of Pb-Bi coolant in KALIMER gives an advantage of higher breeding ratio, smaller burnup reactivity swing and negative coolant void coefficient without any significant degradation of nuclear performance

  5. Reaction of metal oxides with molten mixtures NaPO3+NaCl

    International Nuclear Information System (INIS)

    Kovarskaya, E.N.; Mityakhina, V.S.; Rodionov, Yu.I.; Silin, M.Yu.

    1988-01-01

    By methods of solubility determination and paper chromatography it is shown, that Fe 2 O 3 solution in NaPO 3 +NaCl melts in the air relizes due to its chemical interaction with solvent resulting in formation of iron and sodium binary di- and monophosphates depending on melt-solvent initial composition, its attainment of equilibrium state and experiment temperature. It is established, that oxides increased solubility in melts with NaCl initial content ∼30 mol.% is specified by sodium tri- and tricyclophosphates presence in the melts. On this basis of NGR-spectroscopy data the presence of iron, europium, tin and sodium binary di- and monophosphates in some chloride-polyphosphate melts is confirmed

  6. Crystal structure of polyphosphates NaCd(PO3)3 and NaMn(PO3)3

    International Nuclear Information System (INIS)

    Murashova, E.V.; Chudinova, N.N.

    1997-01-01

    Crystal structure of NaCd(PO 3 ) 3 (1) and NaMn(PO 3 ) 3 (2) isostructural polyphosphates was determined for twin samples. Rhombic lattice parameters of (1): a = 14.678, b = 14.669, c = 14.705 A, sp. gr. P2 1 2 1 2 1 , Z = 16. The structure of compounds is of frame type. Polyphosphate chain with repetition period of 24 PO 4 tetrahedrons contacts with NaO 6 and M 2 O 6 octahedrons by means of common oxygen vertices. Similarities and differences in structure of mentioned polyphosphates and earlier analyzed NaMg(PO 3 ) 3 polyphosphate are noted [ru

  7. Effect of growth in lithium on ouabain binding, Na-K-ATPase and Na and K transport in hela cells.

    Science.gov (United States)

    Boardman, L J; Hume, S P; Lamb, J F; Polson, J

    1975-01-01

    1. HeLa cells were grown for 24 hr in growth medium in which part of the Na was replaced with Li. Ion contents, cell volumes and numbers, Na-K-ATPase and specific ouabain binding were measured. In some experiments the Na efflux and net Na transport was also measured. 2. Growth in Li caused a rise in the specific ouabain binding and membrane Na-K-ATPase of these cells. The Li concentrations in the cells necessary to produce this effect ranged up to 50 mM. 3. It is suggested that Li, like Na, acts on the genetic material of the cells to cause the production of more Na pumps within the membrane. PMID:124350

  8. Effects of EDTA-Na (Na ethylenediaminetetraacetate) upon the metabolism of radiostrontium and radioyttrium in mice

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, T; Wakisaka, G; Kono, T; Hiroaki, A; Yamamasu, T; Sugawa, I

    1954-01-01

    The toxicity of EDTA-Na, inert Sr (NO/sub 3/)/sub 2/ and Ba (NO/sub 3/)/sub 2/ has been examined. Simultaneous injection of EDTA-Na showed no significant effect upon the distribution of radio-Sr in the bones of mice. The distribution of radio-Y in the bones of mice tended to decrease following the simultaneous subcutaneous injection of /sup 91/Y and EDTA-Na.

  9. Hadron distributions - recent results from the CERN experiment NA44

    International Nuclear Information System (INIS)

    Xu, N.

    1996-01-01

    Proton distributions at midrapidity have been measured for 158A circ GeV/c Pb + Pb collisions in the focusing spectrometer experiment NA44 at CERN. A high degree of nuclear stopping is found in the truly heavy ion collisions. Systematic results of single particle transverse momentum distributions of pions, kaons, and protons, of 200A-GeV/c S+S and 158A circ GeV/c Pb+Pb central collisions will be addressed within the context of thermalization. By comparing these data with thermal and transport models, freeze-out parameters such as the temperature parameter T fo and mean collective flow velocity (Β) are extracted. Preliminary results of the particle ratios of K - /K + and p/p are discussed in the context of cascade models of RQMD and VENUS

  10. Novel aspects of Na+,K+-ATPase

    OpenAIRE

    Aizman, Oleg

    2002-01-01

    Na,K-ATPase, an integral membrane protein expressed in each eukaryotic cell, serves as the major determinant of intracellular ion composition. In the current study we investigated novel aspects of Na,K-ATPase function and regulation. It is well established that Na,K-ATPase activity is regulated by reversible phosphorylation. New findings in this study are: 1) the level of intracellular Ca 2. concentration determines the functional effects of PKA and PKC-mediated Na,K-ATP...

  11. High-Performance Na-O2 Batteries Enabled by Oriented NaO2 Nanowires as Discharge Products.

    Science.gov (United States)

    Khajehbashi, S Mohammad B; Xu, Lin; Zhang, Guobin; Tan, Shuangshuang; Zhao, Yan; Wang, Lai-Sen; Li, Jiantao; Luo, Wen; Peng, Dong-Liang; Mai, Liqiang

    2018-06-13

    Na-O 2 batteries are emerging rechargeable batteries due to their high theoretical energy density and abundant resources, but they suffer from sluggish kinetics due to the formation of large-size discharge products with cubic or irregular particle shapes. Here, we report the unique growth of discharge products of NaO 2 nanowires inside Na-O 2 batteries that significantly boosts the performance of Na-O 2 batteries. For this purpose, a high-spin Co 3 O 4 electrocatalyst was synthesized via the high-temperature oxidation of pure cobalt nanoparticles in an external magnetic field. The discharge products of NaO 2 nanowires are 10-20 nm in diameter and ∼10 μm in length, characteristics that provide facile pathways for electron and ion transfer. With these nanowires, Na-O 2 batteries have surpassed 400 cycles with a fixed capacity of 1000 mA h g -1 , an ultra-low over-potential of ∼60 mV during charging, and near-zero over-potential during discharging. This strategy not only provides a unique way to control the morphology of discharge products to achieve high-performance Na-O 2 batteries but also opens up the opportunity to explore growing nanowires in novel conditions.

  12. Prediction of production of {sup 22}Na in a gas-cell target irradiated by protons using Monte Carlo tracking

    Energy Technology Data Exchange (ETDEWEB)

    Eslami, M., E-mail: mohammad.eslami25@yahoo.com [Department of Physics, Faculty of Science, University of Zanjan, Zengan (Zanjan) (Iran, Islamic Republic of); Kakavand, T. [Department of Physics, Faculty of Science, University of Zanjan, Zengan (Zanjan) (Iran, Islamic Republic of); Department of Physics, Faculty of Science, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Mirzaii, M.; Rajabifar, S. [Agricultural, Medical and Industrial Research School, Nuclear Science and Technology Research Institute, AEOI, Karaj (Iran, Islamic Republic of)

    2015-01-01

    Highlights: • Angular distribution of the proton beam in a gaseous environment. • Particle energy distribution profile and proton flux within gas-cell target with MCNPX. • Detection of the residual nuclei during the nuclear reactions. • Estimation of production yield for {sup 22,nat}Ne(p,x){sup 22}Na reactions. - Abstract: The {sup 22}Ne(p,n){sup 22}Na is an optimal reaction for the cyclotron production of {sup 22}Na. This work tends to monitor the proton induced production of {sup 22}Na in a gas-cell target, containing natural and enriched neon gas, using Monte Carlo method. The excitation functions of reactions are calculated by both TALYS-1.6 and ALICE/ASH codes and then the optimum energy range of projectile for the high yield production is selected. A free gaseous environment of neon at a particular pressure and temperature is prearranged and the proton beam is transported within it using Monte Carlo codes MCNPX and SRIM. The beam monitoring performed by each of these codes indicates that the gas-cell has to be designed as conical frustum to reach desired interactions. The MCNPX is also employed to calculate the energy distribution of proton in the designed target and estimation of the residual nuclei during irradiation. The production yield of {sup 22}Na in {sup 22}Ne(p,n){sup 22}Na and {sup nat}Ne(p,x){sup 22}Na reactions are estimated and it shows a good agreement with the experimental results. The results demonstrate that Monte Carlo makes available a beneficial manner to design and optimize the gas targets as well as calibration of detectors, which can be used for the radionuclide production purposes.

  13. Carcinoma apócrino na glândula parótida e na região submandibular Apocrine carcinoma in the parotid gland and in the submandibular region

    Directory of Open Access Journals (Sweden)

    Jairo S. Francisco

    2005-04-01

    Full Text Available Os objetivos deste trabalho consistem na apresentação de um caso de carcinoma apócrino e na discussão de aspectos relacionados ao seu diagnóstico, tratamento e prognóstico. Os carcinomas com diferenciação apócrina que não correspondem aos casos de doença extramamária de Paget, de carcinoma ductal de mama, de adenocarcinoma das glândulas de Moll e de carcinoma ceruminal são tumores muito raros. Relatamos o caso de uma paciente do sexo feminino, negra, com 51 anos, na qual duas lesões de carcinoma apócrino acometeram a parótida esquerda (processo inicial e recidiva e uma lesão envolveu a pele da região submandibular do mesmo lado. O exame histopatológico destas lesões mostrou a presença de neoplasia epitelial glandular infiltrativa com pleomorfismo celular e nuclear moderados; apresentando células poligonais ou arredondadas, com núcleos grandes e citoplasma eosinofílico e granular. Destacou-se a presença de secreção por decapitação apical na maior parte das células tumorais voltadas para a luz das estruturas císticas neoplásicas. Adicionalmente, foi encontrada a presença de focos de comedo-necrose e de material corado pelo PAS com e sem diastase. Apesar de não podermos definir com certeza qual a sede do tumor primário, com base nos aspectos histopatológicos compatíveis com o carcinoma apócrino cutâneo, consideramos que tenha sido, provavelmente, a lesão retirada da pele da região submandibular. A paciente foi submetida a tratamentos cirúrgicos e não apresentou alterações após um ano de acompanhamento, depois da retirada do tumor recidivante na parótida.The objectives of this paper are to report a case of apocrine carcinoma and the discussion of aspects related to its diagnosis, treatment, and prognosis. Carcinomas with apocrine differentiation not related to extramammary Paget's disease, ductal breast carcinoma, Moll's glands adenocarcinoma and ceruminous glands carcinoma are very uncommon tumors. We

  14. Safeguards Guidance Document for Designers of Commercial Nuclear Facilities: International Nuclear Safeguards Requirements and Practices For Uranium Enrichment Plants

    Energy Technology Data Exchange (ETDEWEB)

    Robert Bean; Casey Durst

    2009-10-01

    This report is the second in a series of guidelines on international safeguards requirements and practices, prepared expressly for the designers of nuclear facilities. The first document in this series is the description of generic international nuclear safeguards requirements pertaining to all types of facilities. These requirements should be understood and considered at the earliest stages of facility design as part of a new process called “Safeguards-by-Design.” This will help eliminate the costly retrofit of facilities that has occurred in the past to accommodate nuclear safeguards verification activities. The following summarizes the requirements for international nuclear safeguards implementation at enrichment plants, prepared under the Safeguards by Design project, and funded by the U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA), Office of NA-243. The purpose of this is to provide designers of nuclear facilities around the world with a simplified set of design requirements and the most common practices for meeting them. The foundation for these requirements is the international safeguards agreement between the country and the International Atomic Energy Agency (IAEA), pursuant to the Treaty on the Non-proliferation of Nuclear Weapons (NPT). Relevant safeguards requirements are also cited from the Safeguards Criteria for inspecting enrichment plants, found in the IAEA Safeguards Manual, Part SMC-8. IAEA definitions and terms are based on the IAEA Safeguards Glossary, published in 2002. The most current specification for safeguards measurement accuracy is found in the IAEA document STR-327, “International Target Values 2000 for Measurement Uncertainties in Safeguarding Nuclear Materials,” published in 2001. For this guide to be easier for the designer to use, the requirements have been restated in plainer language per expert interpretation using the source documents noted. The safeguards agreement is fundamentally a

  15. Insight to the Thermal Decomposition and Hydrogen Desorption Behaviors of NaNH2-NaBH4 Hydrogen Storage Composite.

    Science.gov (United States)

    Pei, Ziwei; Bai, Ying; Wang, Yue; Wu, Feng; Wu, Chuan

    2017-09-20

    The lightweight compound material NaNH 2 -NaBH 4 is regarded as a promising hydrogen storage composite due to the high hydrogen density. Mechanical ball milling was employed to synthesize the composite NaNH 2 -NaBH 4 (2/1 molar ratio), and the samples were investigated utilizing thermogravimetric-differential thermal analysis-mass spectroscopy (TG-DTA-MS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) analyses. The full-spectrum test (range of the ratio of mass to charge: 0-200) shows that the released gaseous species contain H 2 , NH 3 , B 2 H 6 , and N 2 in the heating process from room temperature to 400 °C, and possibly the impurity gas B 6 H 12 also exists. The TG/DTA analyses show that the composite NaNH 2 -NaBH 4 (2/1 molar ratio) is conductive to generate hydrogen so that the dehydrogenation process can be finished before 400 °C. Moreover, the thermal decomposition process from 200 to 400 °C involves two-step dehydrogenation reactions: (1) Na 3 (NH 2 ) 2 BH 4 hydride decomposes into Na 3 BN 2 and H 2 (200-350 °C); (2) remaining Na 3 (NH 2 ) 2 BH 4 reacts with NaBH 4 and Na 3 BN 2 , generating Na, BN, NH 3 , N 2 , and H 2 (350-400 °C). The better mechanism understanding of the thermal decomposition pathway lays a foundation for tailoring the hydrogen storage performance of the composite complex hydrides system.

  16. Distinct pH dependencies of Na+/K+ selectivity at the two faces of Na,K-ATPase.

    Science.gov (United States)

    Cornelius, Flemming; Tsunekawa, Naoki; Toyoshima, Chikashi

    2018-02-09

    The sodium pump (Na,K-ATPase) in animal cells is vital for actively maintaining ATP hydrolysis-powered Na + and K + electrochemical gradients across the cell membrane. These ion gradients drive co- and countertransport and are critical for establishing the membrane potential. It has been an enigma how Na,K-ATPase discriminates between Na + and K + , despite the pumped ion on each side being at a lower concentration than the other ion. Recent crystal structures of analogs of the intermediate conformations E2·Pi·2K + and Na + -bound E1∼P·ADP suggest that the dimensions of the respective binding sites in Na,K-ATPase are crucial in determining its selectivity. Here, we found that the selectivity at each membrane face is pH-dependent and that this dependence is unique for each face. Most notable was a strong increase in the specific affinity for K + at the extracellular face ( i.e. E2 conformation) as the pH is lowered from 7.5 to 5. We also observed a smaller increase in affinity for K + on the cytoplasmic side (E1 conformation), which reduced the selectivity for Na + Theoretical analysis of the p K a values of ion-coordinating acidic amino acid residues suggested that the face-specific pH dependences and Na + /K + selectivities may arise from the protonation or ionization of key residues. The increase in K + selectivity at low pH on the cytoplasmic face, for instance, appeared to be associated with Asp 808 protonation. We conclude that changes in the ionization state of coordinating residues in Na,K-ATPase could contribute to altering face-specific ion selectivity. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. OGLAŠEVANJE NA FACEBOOKU

    OpenAIRE

    Renko, Katica

    2013-01-01

    V magistrskem delu smo se seznanili z oglaševanjem na Facebooku. S pregledom gradiva, ki nam je ponujeno, smo preverili pogoje, načine, oblike … oglaševanja, ki pa smo jih s pregledom situacije v praksi preverili in dopolnili. Ob zaključku dela lahko rečemo, da je oglaševanje preko FB enostavnejše, cenejše, dostopnejše, omogoča nam ažurnost in samo komunikacijo z naslovniki, ki so potencialni kupci naših ponudb. Množični mediji nam omogočajo mnogotero obliko oglaševanja. Izbrana oblika ponuja...

  18. Computer simulation of radiation damage in NaCl using a kinetic rate reaction model

    International Nuclear Information System (INIS)

    Soppe, W.J.

    1993-01-01

    Sodium chloride and other alkali halides are known to be very susceptible to radiation damage in the halogen sublattice when exposed to ionizing radiation. The formation of radiation damage in NaCl has generated interest because of the relevance of this damage to the disposal of radioactive waste in rock salt formations. In order to estimate the long-term behaviour of a rock salt repository, an accurate theory describing the major processes of radiation damage in NaCl is required. The model presented in this paper is an extended version of the Jain-Lidiard model; its extensions comprise the effect of impurities and the colloid nucleation stage on the formation of radiation damage. The new model has been tested against various experimental data obtained from the literature and accounts for several well known aspects of radiation damage in alkali halides which were not covered by the original Jain-Lidiard model. The new model thus may be expected to provide more reliable predictions for the build-up of radiation damage in a rock salt nuclear waste repository. (Author)

  19. Effect of the addition of Na2O on the thermal properties and chemical durability of glasses of iron and uranium phosphates

    International Nuclear Information System (INIS)

    Arboleda Zuluaga, P.A; Rodriguez, D.S; Gonzalez Oliver, C; Rincon Lopez, J.M; Soldera, F

    2012-01-01

    A series of glass compositions including (54,6-73,5P 2 O 5 .14-22Fe 2 O 3.x Na 2 O.2,8-4,25 UO 2 ) %mol. x=0-28,4 were studied in function of sodium oxide content for the thermal properties and chemical durability. By means differential dilatometer measurements was possible establish the variation of Tg, and α Tsoft and analysis of the kinetics of sintering by means of High Temperature Microscopy (MAT) and dilatometric data of pressed pellets. The presence of modifier oxides in the structure of iron phosphate glasses causes slightly onset sintering anticipation in almost 25 o C The chemical durability was estimated performing the named Product Consistency Test (PCT-B) focused on determining the resistance of glasses for nuclear wastes. These glasses exhibit good chemical durability but it is significant impaired by the addition of x≥6wt%Na 2 O. It is aimed to achieve more stable compositions and get glass matrixes able to contain more uranium oxides allowing evaluating the potential application of these iron phosphate glasses for special, industrial and nuclear waste immobilization

  20. Laser-induced ionization of Na vapor

    International Nuclear Information System (INIS)

    Wu, R.C.Y.; Judge, D.L.; Roussel, F.; Carre, B.; Breger, P.; Spiess, G.

    1982-01-01

    The production of Na 2 + ions by off-resonant laser excitation in the 5800-6200A region mainly results from two-photon absorption by the Na 2 molecule to highly excited gerade states followed by (a) direct ionization by absorbing a third photon or (b) coupling to the molecular Na 2 D 1 PIμ Rydberg state which is subsequently ionized by absorbing a third photon. This mechanism, i.e., a two-photon resonance three photon ionization process, explains a recent experimental observation of Roussel et al. It is suggested that the very same mechanism is also responsible for a similar observation reported by Polak-Dingels et al in their work using two crossed Na beams. In the latter two studies the laser-induced associative ionization processes were reported to be responsible for producing the Na 2 + ion. From the ratio of molecular to atomic concentration in the crossed beam experiment of Polak-Dingels et al we estimate that the cross section for producing Na 2 + through laser-induced associative ionization is at least four orders of magnitude smaller than ionization through the two-photon resonance three photon ionization process in Na 2 molecules

  1. Effects of Na and K ions on the crystallization of low-silica X zeolite and its catalytic performance for alkylation of toluene with methanol

    Energy Technology Data Exchange (ETDEWEB)

    Hui, Haitao; Gao, Junhua; Wang, Gencun; Liu, Ping; Zhang, Kan, E-mail: gaojunhua@sxicc.ac.cn, E-mail: zhangkan@sxicc.ac.cn [State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan (China)

    2014-01-15

    The crystallization of low-silica X zeolite (LSX) was studied in Na-K gel systems with different extents of replacement of Na by K while fixed content of other components. X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, scanning electron microscopy, infrared spectra, and nuclear magnetic resonance were used to characterize liquid and solid phase. In the synthesis of LSX, the molar ratio of K/(Na + K) affects the crystallization and the composition of final products. A higher mole fraction of K corresponded to a lower crystallization rate, higher concentration of Si in the liquid phase, and lower Si/Al ratio of the obtained LSX. The average size of LSX products steadily increased with the progressive replacement of Na by K in the initial gels, and crystal morphology of the LSX products gradually changed from round to octahedral. For alkylation of toluene with methanol over obtained LSX, the selectivity of ring alkylation product xylene decreased while the side chain alkylation products styrene and ethylbenzene increased with the increased x values except x = 0, which was due to its low crystallinity. (author)

  2. Effects of Na and K ions on the crystallization of low-silica X zeolite and its catalytic performance for alkylation of toluene with methanol

    International Nuclear Information System (INIS)

    Hui, Haitao; Gao, Junhua; Wang, Gencun; Liu, Ping; Zhang, Kan

    2014-01-01

    The crystallization of low-silica X zeolite (LSX) was studied in Na-K gel systems with different extents of replacement of Na by K while fixed content of other components. X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, scanning electron microscopy, infrared spectra, and nuclear magnetic resonance were used to characterize liquid and solid phase. In the synthesis of LSX, the molar ratio of K/(Na + K) affects the crystallization and the composition of final products. A higher mole fraction of K corresponded to a lower crystallization rate, higher concentration of Si in the liquid phase, and lower Si/Al ratio of the obtained LSX. The average size of LSX products steadily increased with the progressive replacement of Na by K in the initial gels, and crystal morphology of the LSX products gradually changed from round to octahedral. For alkylation of toluene with methanol over obtained LSX, the selectivity of ring alkylation product xylene decreased while the side chain alkylation products styrene and ethylbenzene increased with the increased x values except x = 0, which was due to its low crystallinity. (author)

  3. Characterization and antibacterial activity of silver exchanged regenerated NaY zeolite from surfactant-modified NaY zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Salim, Mashitah Mad; Malek, Nik Ahmad Nizam Nik, E-mail: niknizam@fbb.utm.my

    2016-02-01

    The antibacterial activity of regenerated NaY zeolite (thermal treatment from cetyltrimethyl ammonium bromide (CTAB)-modified NaY zeolite and pretreatment with Na ions) loaded with silver ions were examined using the broth dilution minimum inhibitory concentration (MIC) method against Escherichia coli (E. coli ATCC 11229) and Staphylococcus aureus (S. aureus ATCC 6538). X-ray diffraction (XRD), attenuated total reflectance–Fourier transform infrared (ATR–FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and chemical elemental analyses were used to characterize the regenerated NaY and AgY zeolites. The XRD patterns indicated that the calcination and addition of silver ions on regenerated NaY zeolite did not affect the structure of the regenerated NaY zeolite as the characteristic peaks of the NaY zeolite were retained, and no new peaks were observed. The regenerated AgY zeolite showed good antibacterial activity against both bacteria strains in distilled water, and the antibacterial activity of the samples increased with increasing Ag loaded on the regenerated AgY zeolite; the regenerated AgY zeolite was more effective against E. coli than S. aureus. However, the antibacterial activity of the regenerated AgY was not effective in saline solution for both bacteria. The study showed that CTAB-modified NaY zeolite materials could be regenerated to NaY zeolite using thermal treatment (550 °C, 5 h) and this material has excellent performance as an antibacterial agent after silver ions loading. - Highlights: • Thermal treatment was used to regenerate surfactant modified zeolite. • The regenerated NaY zeolite formed was added with different silver loadings. • Regenerated AgY zeolite was tested for antibacterial activity on E. coli and S. aureus. • The antibacterial activity increased with increased of the amount of silver loadings. • The zeolite structure did not change with thermal and modification

  4. Characterization and antibacterial activity of silver exchanged regenerated NaY zeolite from surfactant-modified NaY zeolite

    International Nuclear Information System (INIS)

    Salim, Mashitah Mad; Malek, Nik Ahmad Nizam Nik

    2016-01-01

    The antibacterial activity of regenerated NaY zeolite (thermal treatment from cetyltrimethyl ammonium bromide (CTAB)-modified NaY zeolite and pretreatment with Na ions) loaded with silver ions were examined using the broth dilution minimum inhibitory concentration (MIC) method against Escherichia coli (E. coli ATCC 11229) and Staphylococcus aureus (S. aureus ATCC 6538). X-ray diffraction (XRD), attenuated total reflectance–Fourier transform infrared (ATR–FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and chemical elemental analyses were used to characterize the regenerated NaY and AgY zeolites. The XRD patterns indicated that the calcination and addition of silver ions on regenerated NaY zeolite did not affect the structure of the regenerated NaY zeolite as the characteristic peaks of the NaY zeolite were retained, and no new peaks were observed. The regenerated AgY zeolite showed good antibacterial activity against both bacteria strains in distilled water, and the antibacterial activity of the samples increased with increasing Ag loaded on the regenerated AgY zeolite; the regenerated AgY zeolite was more effective against E. coli than S. aureus. However, the antibacterial activity of the regenerated AgY was not effective in saline solution for both bacteria. The study showed that CTAB-modified NaY zeolite materials could be regenerated to NaY zeolite using thermal treatment (550 °C, 5 h) and this material has excellent performance as an antibacterial agent after silver ions loading. - Highlights: • Thermal treatment was used to regenerate surfactant modified zeolite. • The regenerated NaY zeolite formed was added with different silver loadings. • Regenerated AgY zeolite was tested for antibacterial activity on E. coli and S. aureus. • The antibacterial activity increased with increased of the amount of silver loadings. • The zeolite structure did not change with thermal and modification

  5. Sodium zirconium phosphate (NZP) as a host structure for nuclear waste immobilization: A review

    International Nuclear Information System (INIS)

    Scheetz, B.E.; Agrawal, D.K.; Breval, E.; Roy, R.

    1994-01-01

    Sodium zirconium phosphate [NZP] structural family, of which NaZr 2 P 3 O 12 is the parent composition, has been reviewed as a host ceramic waste form for nuclear waste immobilization. NZP compounds are characterized for their ionic conductivity, low thermal expansion and structural flexibility to accommodate a large number of multivalent ions. This latter property of the [NZP] structure allows the incorporation of almost all 42 nuclides present in a typical commercial nuclear waste. The leach studies of simulated waste forms based on NZP have shown reasonable resistance for the release of its constituents. The calculation of dissolution rates of NZP structure has demonstrated that it would take 20,000 times longer to dissolved NZP than quartz

  6. Carbon dioxide sequestration using NaHSO4 and NaOH: A dissolution and carbonation optimisation study.

    Science.gov (United States)

    Sanna, Aimaro; Steel, Luc; Maroto-Valer, M Mercedes

    2017-03-15

    The use of NaHSO 4 to leach out Mg fromlizardite-rich serpentinite (in form of MgSO 4 ) and the carbonation of CO 2 (captured in form of Na 2 CO 3 using NaOH) to form MgCO 3 and Na 2 SO 4 was investigated. Unlike ammonium sulphate, sodium sulphate can be separated via precipitation during the recycling step avoiding energy intensive evaporation process required in NH 4 -based processes. To determine the effectiveness of the NaHSO 4 /NaOH process when applied to lizardite, the optimisation of the dissolution and carbonation steps were performed using a UK lizardite-rich serpentine. Temperature, solid/liquid ratio, particle size, concentration and molar ratio were evaluated. An optimal dissolution efficiency of 69.6% was achieved over 3 h at 100 °C using 1.4 M sodium bisulphate and 50 g/l serpentine with particle size 75-150 μm. An optimal carbonation efficiency of 95.4% was achieved over 30 min at 90 °C and 1:1 magnesium:sodium carbonate molar ratio using non-synthesised solution. The CO 2 sequestration capacity was 223.6 g carbon dioxide/kg serpentine (66.4% in terms of Mg bonded to hydromagnesite), which is comparable with those obtained using ammonium based processes. Therefore, lizardite-rich serpentinites represent a valuable resource for the NaHSO 4 /NaOH based pH swing mineralisation process. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Production of /sup 77/Br for nuclear medicine using the CV-28 cyclotron of Instituto de Engenharia Nuclear (RJ, Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Bastos, M A.V.; Silva, A.G. da [Instituto de Engenharia Nuclear, Rio de Janeiro (Brazil); Newton, W A [Manchester Univ. (UK)

    1984-06-01

    The reaction /sup 75/As (..cap alpha..,2n)/sup 77/Br with 28 MeV alpha particles is used to obtain /sup 77/Br with the CV-28 cyclotron of Instituto de Engenharia Nuclear (Rio de Janeiro, Brazil). A production method has been developed, using 200 mg of arsenium metal, electroplated on platinum. These targets can withstand 25 ..mu..A beams for several hours, yielding 0.29 mCi/..mu..A h. The /sup 77/Br which is separated by coprecipitation with AgCl, is recovered as NaBr with yields better than 98%. Measures have been taken to obtain a product which is pure, sterile and carrier-free.

  8. Nuclear energy and the nuclear industry

    International Nuclear Information System (INIS)

    1979-01-01

    These notes have been prepared by the Department of Energy to provide information and to answer questions often raised about nuclear energy and the nuclear industry and in the hope that they will contribute to the public debate about the future of nuclear energy in the UK. The subject is dealt with under the headings; contribution of nuclear power, energy forecasts, nuclear fuels and reactor types, cost, thermal reactor strategy, planning margin, safety, nuclear licensing, unlike an atomic bomb, radiation, waste disposal, transport of nuclear materials, emergency arrangements at nuclear sites, siting of nuclear stations, security of nuclear installations, world nuclear programmes, international regulation and non-proliferation, IAEA safeguards arrangements in the UK, INFCE, and uranium supplies. (U.K.)

  9. Characterization and antibacterial activity of silver exchanged regenerated NaY zeolite from surfactant-modified NaY zeolite.

    Science.gov (United States)

    Salim, Mashitah Mad; Malek, Nik Ahmad Nizam Nik

    2016-02-01

    The antibacterial activity of regenerated NaY zeolite (thermal treatment from cetyltrimethyl ammonium bromide (CTAB)-modified NaY zeolite and pretreatment with Na ions) loaded with silver ions were examined using the broth dilution minimum inhibitory concentration (MIC) method against Escherichia coli (E. coli ATCC 11229) and Staphylococcus aureus (S. aureus ATCC 6538). X-ray diffraction (XRD), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and chemical elemental analyses were used to characterize the regenerated NaY and AgY zeolites. The XRD patterns indicated that the calcination and addition of silver ions on regenerated NaY zeolite did not affect the structure of the regenerated NaY zeolite as the characteristic peaks of the NaY zeolite were retained, and no new peaks were observed. The regenerated AgY zeolite showed good antibacterial activity against both bacteria strains in distilled water, and the antibacterial activity of the samples increased with increasing Ag loaded on the regenerated AgY zeolite; the regenerated AgY zeolite was more effective against E. coli than S. aureus. However, the antibacterial activity of the regenerated AgY was not effective in saline solution for both bacteria. The study showed that CTAB-modified NaY zeolite materials could be regenerated to NaY zeolite using thermal treatment (550°C, 5h) and this material has excellent performance as an antibacterial agent after silver ions loading. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Composition and thermochemistry of the equilibrium vapour of the systems NaI-FeI2 and NaI-PbI2

    International Nuclear Information System (INIS)

    Hilpert, K.; Gerads, H.; Koberts, D.; Miller, M.

    1987-01-01

    The vaporization of NaI/FeI 2 and NaI/PbI 2 samples of equimolar composition was investigated was investigated in the temperature ranges between 574 to 683 K and 562 to 669 K, respectively, by using the mass spectrometric Knudsen effusion method. The gaseous species I, I 2 , NaI, (NaI) 2 , FeI 2 , (FeI 2 ) 2 , FeI 3 , NaFeI 3 , and Na 2 FeI 4 (NaI-FeI 2 system) as well as NaI, (NaI) 2 , PbI 2 , (PbI 2 ) 2 , and NaPbI 3 (NaI-PbI 2 system) are present in the equilibrium vapours. The equilibrium partial pressures of these species were determined with the exception of I, I 2 , and FeI 3 . Enthalpies and entropies of dissociation resulted for the reactions NaFeI 3 (g) ↔ NaI(g)+FeI 2 (g) (1), Na 2 FeI 4 (g) ↔ 2NaI(g)+FeI 2 (g) and (2) NaPbI 3 (g) ↔ NaI(g)+PbI 2 (g) (3) as Δ d H 298 0 (Eq. (1)) = 184±5 kJ mol -1 , Δ d S 298 0 (Eq. (1)) = 143±8 J mol -1 K -1 ; Δ d H 298 0 (Eq. (2)) = 333±9 kJ mol -1 , Δ d S 298 0 (Eq. (2)) = 274±14 J mol -1 K -1 ; and Δ d H 298 0 (Eq. (3)) = 168±5 kJ mol -1 , Δ d S 298 0 (Eq. (3)) = 151±9 J mol -1 K -1 . Equilibrium constants for these reactions are additionally given. The pressures of NaFeI 3 (g) and NaPbI 3 (g) as all as their enthalpies of dissociation are discussed with respect to their significance of semi empirical rules. (orig.)

  11. Adsorption and Formation of Small Na Clusters on Pristine and Double-Vacancy Graphene for Anodes of Na-Ion Batteries.

    Science.gov (United States)

    Liang, Zhicong; Fan, Xiaofeng; Zheng, Weitao; Singh, David J

    2017-05-24

    Layered carbon is a likely anode material for Na-ion batteries (NIBs). Graphitic carbon has a low capacity of approximately 35 (mA h)/g due to the formation of NaC 64 . Using first-principles methods including van der Waals interactions, we analyze the adsorption of Na ions and clusters on graphene in the context of anodes. The interaction between Na ions and graphene is found to be weak. Small Na clusters are not stable on the surface of pristine graphene in the electrochemical environment of NIBs. However, we find that Na ions and clusters can be stored effectively on defected graphene that has double vacancies. In addition, the adsorption energy of small Na clusters near a double vacancy is found to decrease with increasing cluster size. With high concentrations of vacancies the capacity of Na on defective graphene is found to be as much as 10-30 times higher than that of graphitic carbon.

  12. Thermodynamic modeling of neptunium(V) solubility in concentrated Na-CO3-HCO3-Cl-ClO4-H-OH-H2O systems

    International Nuclear Information System (INIS)

    Novak, C.F.; Roberts, K.E.

    1994-01-01

    Safety assessments of nuclear waste repositories often require estimation of actinide solubilities as a function of groundwater composition. Although considerable amount of research has been done on the solubility and speciation of actinides, relatively little has been done to unify these data into a model applicable to concentrate brines. Numerous authors report data on the aqueous chemical properties of Np(V) in NaClO 4 , Na 2 CO 3 , and NaCl media, but a consistent thermodynamic model for predicting these properties is not available. To meet this need, a model was developed to describe the solubility of Np(V) in Na-Cl-ClO 4 -CO 3 aqueous systems, based on the Pitzer activity coefficient formalism for concentrated electrolytes. Hydrolysis and/or carbonate complexation are the dominant aqueous reactions with neptunyl in these systems. Literature data for neptunyl extraction and solubility, and solubility data that the authors developed, are used to parameterize an integrated model for Np(V) solubility in the Np(V)-Na-CO 3 -HCO 3 -Cl-ClO 4 -H-OH-H 2 O system. The resulting model is tested against additional solubility data, and compared with Np(V) solubility experiments in complex synthetic brines

  13. Nepheline Crystallization in Nuclear Waste Glasses: Progress toward acceptance of high-alumina formulations

    International Nuclear Information System (INIS)

    McCloy, John S.; Schweiger, Michael J.; Rodriguez, Carmen P.; Vienna, John D.

    2011-01-01

    We have critically compiled and analyzed historical data for investigating the quantity of nepheline (NaAlSiO4) precipitation as a function of composition in simulated nuclear waste glasses. To understand composition we used two primary methods: (1) investigating the Al2O3-SiO2-Na2O ternary with filtering for different B2O3 levels and (2) creating a quadrant system consisting of compositions reduced to two metric numbers. These metrics are (1) the nepheline discriminator (ND) which depends only on the SiO2 content by weight normalized to the total weight of the Al2O3-SiO2-Na2O sub-mixture and (2) the optical basicity (OB) which contains contributions from all constituents in the glass. Nepheline precipitation is expected to be suppressed at high SiO2 levels (ND >0.62) or at low basicities (OB 5 wt% B2O3. The OB concept can help further refine regions of nepheline-free glass formation.

  14. Na/Ca Intermixing around Silicate and Phosphate Groups in Bioactive Phosphosilicate Glasses Revealed by Heteronuclear Solid-State NMR and Molecular Dynamics Simulations.

    Science.gov (United States)

    Mathew, Renny; Stevensson, Baltzar; Edén, Mattias

    2015-04-30

    We characterize the intermixing of network-modifying Na(+)/Ca(2+) ions around the silicate (QSi(n)) and phosphate (QP(n)) tetrahedra in a series of 16 Na2O–CaO–SiO2–P2O5 glasses, whose P content and silicate network connectivity were varied independently. The set includes both bioactive and bioinactive compositions and also encompasses two soda-lime-silicate members devoid of P, as well as two CaO–SiO2 glasses and one Na2O–SiO2–P2O5 glass. The various Si/P↔Na/Ca contacts were probed by molecular dynamics (MD) simulations together with heteronuclear magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) experimentation utilizing (23)Na{(31)P} and (23)Na{(29)Si} REDOR, as well as (31)P{ (23)Na} and (29)Si{(23)Na} REAPDOR. We introduce an approach for quantifying the extent of Na(+)/Ca(2+) ordering around a given QP(n) or QSi(n) group, encoded by the preference factor 0⩽ PM ⩽ 1 conveying the relative weights of a random cation intermixing (PM = 0) and complete preference/ordering (PM = 1) for one of the species M, which represents either Na(+) or Ca(2+). The MD-derived preference factors reveal phosphate and silicate species surrounded by Na(+)/Ca(2+) ions intermixed nearly randomly (PM ≲ 0.15), except for the QSi(4) and QSi(1) groups, which manifest more significant cation ordering with preference for Na+ and Ca2+, respectively. The overall weak preferences are essentially independent of the Si and P contents of the glass, whereas PM primarily correlates with the total amount of network modifiers: as the latter is increased, the Na/Ca distribution around the {QP(0), QSi(1), QSi(2)} groups with preference for Ca2(+ )tend to randomize (i.e., PCa decreases), while the PNa-values grow slightly for the {QP(1), QSi(3), QSi(4)} species already preferring coordination of Na. The set of experimental preference factors {PCa} for the orthophosphate (QP(0)) groups extracted from (31)P{(23)Na} REAPDOR NMR-derived M2(P–Na) dipolar second moments agrees

  15. Molecular dynamics simulations of the three-layer hydrate of Na-montmorillonite

    International Nuclear Information System (INIS)

    Holmboe, Michael; Bourg, Ian C.

    2012-01-01

    Document available in extended abstract form only. In many nuclear waste repositories concepts, compacted and smectite-rich bentonite clay is considered as an engineered transport barrier surrounding the canisters holding the nuclear waste. One of the requirements in the safety assessment of these repositories is to predict the transport rate of radionuclides as well as the overall hydraulic conductivity through the bentonite barrier. Kozaki and co-workers have obtained important information from diffusion experiments in bentonite on the mechanisms that control solute transport by studying the temperature-dependence of apparent diffusivity for solutes such as Na + , Cs + and Sr 2+ . Their results showed that the apparent diffusivity follows an Arrhenius relation (ln D a ∝ -E A /RT) with distinct activation energies of diffusion (E A ) for certain montmorillonite compactions, ionic strengths, and types of interlayer cation (Na + vs. Ca 2+ ). Their results suggest that solutes follow different diffusion pathways in compacted montmorillonite at different experimental conditions. In order to identify these transport pathways in compacted montmorillonite one needs independent knowledge of the relative abundance of the different types of interlayer nano-pores, i.e. the different coexisting hydration states (1W-3W), and of the molecular-scale EA for solute diffusion on the external basal surfaces of montmorillonite particles and in the interlayer nano-pores. The latter property can be obtained using molecular dynamics (MD) simulations, an important tool in the characterization of clays and clay minerals that yields detailed atomistic insights into the structural, dynamical and thermodynamic properties of many different geochemically relevant systems. In particular, MD simulations yield insight into the behavior of individual atoms, where most experimental methods only would probe the average behavior of large numbers of atoms or molecules. Thus, by simulating systems of

  16. Novel regulation of cardiac Na pump via phospholemman.

    Science.gov (United States)

    Pavlovic, Davor; Fuller, William; Shattock, Michael J

    2013-08-01

    As the only quantitatively significant Na efflux pathway from cardiac cells, the Na/K ATPase (Na pump) is the primary regulator of intracellular Na. The transmembrane Na gradient it establishes is essential for normal electrical excitability, numerous coupled-transport processes and, as the driving force for Na/Ca exchange, thus setting cardiac Ca load and contractility. As Na influx varies with electrical excitation, heart rate and pathology, the dynamic regulation of Na efflux is essential. It is now widely recognized that phospholemman, a 72 amino acid accessory protein which forms part of the Na pump complex, is the key nexus linking cellular signaling to pump regulation. Phospholemman is the target of a variety of post-translational modifications (including phosphorylation, palmitoylation and glutathionation) and these can dynamically alter the activity of the Na pump. This review summarizes our current understanding of the multiple regulatory mechanisms that converge on phospholemman and govern NA pump activity in the heart. The corrected Fig. 4 is reproduced below. The publisher would like to apologize for any inconvenience caused. [corrected]. Copyright © 2013. Published by Elsevier Ltd.

  17. Multiple sclerosis test or the 4 humors: cerebrospinal fluid serum, tears and saliva; Esclerosis multiple test de los 4 humores: liquido cefalorraquideo, suero, lagrimas y saliva

    Energy Technology Data Exchange (ETDEWEB)

    Oehninger Gatti, C; Buzo Del Puerto, R; Chouza Antelo, C; Scotti Bianchi, C; Cibils, D; Alcantara Pelaez, J; Gomez, A; Heuguerot Oliveira, C

    1994-12-15

    4 were studied biological fluids easily accessible to the immune exploration (cerebrospinal fluid, serum, tears and saliva) in 25 patients with Multiple Sclerosis (MS) during a push clinical disease. The level of interleukin-2 receptor soluble (RsIL-2) was significantly increased by at least 3 of these 4 fluids, compared with normal controls. The sensitivity and specificity of its determination for the diagnosis of the condition was higher than other immunochemical parameters, oligoclonal distribution (OD) of immunoglobulin (Ig) light chain imbalance-and-evoked electrophysiological studies. This method is used to establish a more accurate diagnosis of Multiple Sclerosis as well as to monitor its biological activity with nuclear magnetic resonance (NMR) (Author) [Spanish] Se estudiaron 4 fluidos biologicos de facil acceso a la exploracion inmune (liquido cefalorraquideo, suero, lagrimas y saliva) en 25 pacientes con Esclerosis Multiple (EM) obtenidos durante un empuje clinico de la enfermedad. El nivel del receptor de Interleukina-2 soluble (RsIL-2) se encontro significativamente aumentado en por lo menos 3 de estos 4 fluidos, en comparacion con el de los controles normales. La sensibilidad y especificidad de su determinacion para el diagnostico de la afeccion, fue mayor que la de otros parametros inmunoquimicos - distribucion oligoclonal (DO) de inmunoglobulinas (Ig), disbalance de cadenas livianas - y estudios electrofisiologicos -potenciales evocados-. Este metodo es utilizado para establecer un diagnostico mas certero de la Esclerosis Multiple asi como tambien para monitorizar su actividad biologica junto con la resonancia magnetica nuclear (RMN)(Author)

  18. Theoretical investigation of the relative stability of Na{sup +}He{sub n} (n = 2–24) clusters: Many-body versus delocalization effects

    Energy Technology Data Exchange (ETDEWEB)

    Issaoui, Noureddine, E-mail: issaoui-noureddine@yahoo.fr; Abdessalem, Kawther; Ghalla, Houcine [Faculty of Sciences, Quantum Physics Laboratory, University of Monastir, Monastir 5079 (Tunisia); Yaghmour, Saud Jamil [Faculty of Science, King Abdul-Aziz University, Jeddah (Saudi Arabia); Calvo, Florent [University of Grenoble Alpes, LIPHY, F-38000 Grenoble, France and CNRS, LIPHY, F-38000 Grenoble (France); Oujia, Brahim [Faculty of Sciences, Quantum Physics Laboratory, University of Monastir, Monastir 5079 (Tunisia); Faculty of Science, King Abdul-Aziz University, Jeddah (Saudi Arabia)

    2014-11-07

    The solvation of the Na{sup +} ion in helium clusters has been studied theoretically using optimization methods. A many-body empirical potential was developed to account for Na{sup +}–He and polarization interactions, and the most stable structures of Na{sup +}He{sub n} clusters were determined using the basin-hopping method. Vibrational delocalization was accounted for using zero-point energy corrections at the harmonic or anharmonic levels, the latter being evaluated from quantum Monte Carlo simulations for spinless particles. From the static perspective, many-body effects are found to play a minor role, and the structures obtained reflect homogeneous covering up to n = 10, followed by polyicosahedral packing above this size, the cluster obtained at n = 12 appearing particularly stable. The cationic impurity binds the closest helium atoms sufficiently to negate vibrational delocalization at small sizes. However, this snowball effect is obliterated earlier than shell completion, the nuclear wavefunctions of {sup 4}He{sub n}Na{sup +} with n = 5–7, and n > 10 already exhibiting multiple inherent structures. The decrease in the snowball size due to many-body effects is consistent with recent mass spectrometry measurements.

  19. Financing arrangements for nuclear power projects - past and present experience and future expectations

    International Nuclear Information System (INIS)

    Ispas, G.

    2004-01-01

    The intent of the author of the present paper is to demonstrate, in a practical manner, the role of the past experience and the new approaches of the nuclear projects financing, especially as nuclear generation financing in developing countries involves complex issues that need to be fully understood and dealt with by all the parties involved, namely: high investment costs, generally long construction periods, a high degree of uncertainty with respect to costs and schedule and to public acceptance, particularly because of safety, waste disposal and non-proliferation issues. Moreover, as many associations whose activities consist of ensuring and facilitating at different levels the exchange of knowledge between generations, i.e.: European Nuclear Society (ENS) Young Generation, North American Young Generation in Nuclear (NA-YGN), the goal of the paper is also to outline the importance of the education in nuclear field, i.e. training a young team of specialists to be ready to take over the movement and responsibility in continuing the further development of nuclear program in Romania, mainly with view to the Financing Arrangements for Nuclear Power Projects. The first part of the paper is referring to general financing procedures, while the second part is focusing on a case study related to the: past experience the financing scheme of Cernavoda NPP Unit 1, present or actual experience ongoing financing issues for Cernavoda NPP Unit 2 and potential future shared contribution to the financing of the next Cernavoda NPP units.(author)

  20. All new for NA62

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    This week sees the start of the first run of the new NA62 experiment. This will be a unique opportunity for the collaboration to test its new beam, new detectors and new data acquisition system before the physics run in 2014. Speaking to the Bulletin, the NA62 technical coordinator Ferdinand Hahn shares the many challenges that the various teams faced to be on time for beam. Ready, steady, start!   A Large Angle Veto detector (white) in place in the NA62 decay volume (blue). With components from almost all the detectors in place downstream of the decay point of the mother particles – the kaons – and of the KTAG detector that tags the kaons before they decay, NA62 is ready for its first technical run. This unique run will test all the equipment as well as the trigger and the data acquisition systems. “This year, we will have about five weeks of beam from the SPS before the long shutdown of all the CERN machines,” says Ferdinand Hahn, NA62 Technical Co-...

  1. Effect of chloride substitution on the order–disorder transition in NaBH4 and Na11BD4

    International Nuclear Information System (INIS)

    Olsen, Jørn Eirik; Karen, Pavel; Sørby, Magnus H.; Hauback, Bjørn C.

    2014-01-01

    Graphical abstract: Interactions that order the BD 4 - tetrahedra below the order–disorder transition became increasingly frustrated by the solute in the Na( 11 BD 4 ) 1−x Cl x solid solutions, and the order disappears at x = 0.158. Highlights: • The order–disorder transition temperature for Na(BH 4 ) 1−x Cl x and Na( 11 BD 4 ) 1−x Cl x is highly dependent on the Cl-content, x. • The transition is characterized by DSC for Na( 11 BD 4 ) 1−x Cl x for x = 0, 0.10 and 0.15. • No transition is observed for x ⩾ 0.20 on cooling to 8 K. • The crystal structures are reported for Na 11 BD 4 at room temperature and 8 K and Na( 11 BD 4 ) 1−x Cl x (x = 0.10, 0.15, 0.20 and 0.25) at 8 K from powder neutron diffraction. -- Abstract: Phase transition associated with anion disordering over two orientations in Na 11 BD 4 (NaBH 4 ) and its solid solutions with NaCl, Na( 11 BD 4 ) 1−x Cl x , is investigated with powder diffraction (neutron and synchrotron radiation), differential scanning calorimetry and Raman spectroscopy. Upon heating, the transition temperature extrapolated to zero rate of heating is 192.2 K for Na 11 BD 4 , ΔS = 4.41 J/mol K, hysteresis 1.7 K and the volume increase 0.43%. Thermal parameters of the transition in Na( 11 BD 4 ) 1−x Cl x follow a colligative-property model of an ideal solution, with x = 0.158(1) as the critical concentration at which the ordering interactions and the transition itself are eliminated. On approaching this limit, the tetragonal distortion of the ordered structure decreases somewhat towards the cubic average, and this is associated with a partial disorder of the tetrahedral anions seen by diffraction methods. In fact, a 3% disorder is already present in the pure solvent of the solid solution (Na 11 BD 4 ) at 8 K

  2. Liquid-Liquid Phase Separation in Model Nuclear Waste Glasses: A Solid-State Double-Resonance NMR Study

    Energy Technology Data Exchange (ETDEWEB)

    Martineau, Ch.; Michaelis, V.K.; Kroeker, S. [Univ Manitoba, Dept Chem, Winnipeg, MB R3T 2N2 (Canada); Schuller, S. [CEA Valrho Marcoule, LDMC, SECM, DTCD, DEN, F-30207 Bagnols Sur Ceze (France)

    2010-07-01

    Double-resonance nuclear magnetic resonance (NMR) techniques are used in addition to single-resonance NMR experiments to probe the degree of mixing between network-forming cations Si and B, along with the modifier cations Cs{sup +} and Na{sup +} in two molybdenum-bearing model nuclear waste glasses. The double-resonance experiments involving {sup 29}Si in natural abundance are made possible by the implementation of a CPMG pulse-train during the acquisition period of the usual REDOR experiments. For the glass with lower Mo content, the NMR results show a high degree of Si-B mixing, as well as an homogeneous distribution of the cations within the borosilicate network, characteristic of a non-phase-separated glass. For the higher-Mo glass, a decrease of B-Si(Q{sup 4}) mixing is observed, indicating phase separation. {sup 23}Na and {sup 133}Cs NMR results show that although the Cs{sup +} cations, which do not seem to be influenced by the molybdenum content, are spread within the borate network, there is a clustering of the Na{sup +} cations, very likely around the molybdate units. The segregation of a Mo-rich region with Na{sup +} cations appears to shift the bulk borosilicate glass composition toward the metastable liquid liquid immiscibility region and induce additional phase separation. Although no crystallization is observed in the present case, this liquid liquid phase separation is likely to be the first stage of crystallization that can occur at higher Mo loadings or be driven by heat treatment. From this study emerges a consistent picture of the nature and extent of such phase separation phenomena in Mo-bearing glasses, and demonstrates the potential of double-resonance NMR methods for the investigation of phase separation in amorphous materials. (authors)

  3. Reduced resting potentials in dystrophic (mdx) muscle fibers are secondary to NF-κB-dependent negative modulation of ouabain sensitive Na+-K+ pump activity.

    Science.gov (United States)

    Miles, M T; Cottey, E; Cottey, A; Stefanski, C; Carlson, C G

    2011-04-15

    To examine potential mechanisms for the reduced resting membrane potentials (RPs) of mature dystrophic (mdx) muscle fibers, the Na(+)-K(+) pump inhibitor ouabain was added to freshly isolated nondystrophic and mdx fibers. Ouabain produced a 71% smaller depolarization in mdx fibers than in nondystrophic fibers, increased the [Na(+)](i) in nondystrophic fibers by 40%, but had no significant effect on the [Na(+)](i) of mdx fibers, which was approximately double that observed in untreated nondystrophic fibers. Western blots indicated no difference in total and phosphorylated Na(+)-K(+) ATPase catalytic α1 subunit between nondystrophic and mdx muscle. Examination of the effects of the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) indicated that direct application of the drug slowly hyperpolarized mdx fibers (7 mV in 90 min) but had no effect on nondystrophic fibers. Pretreatment with ouabain abolished this hyperpolarization, and pretreatment with PDTC restored ouabain-induced depolarization and reduced [Na(+)](i). Administration of an NF-κB inhibitor that utilizes a different mechanism for reducing nuclear NF-κB activation, ursodeoxycholic acid (UDCA), also hyperpolarized mdx fibers. These results suggest that in situ Na(+)-K(+) pump activity is depressed in mature dystrophic fibers by NF-κB dependent modulators, and that this reduced pump activity contributes to the weakness characteristic of dystrophic muscle. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Neutron diffraction studies of the Na-ion battery electrode materials NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Yahia, H. Ben [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 5825 Doha (Qatar); Essehli, R., E-mail: ressehli@qf.org.qa [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 5825 Doha (Qatar); Avdeev, M. [Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights NSW 2234 (Australia); Park, J-B.; Sun, Y-K. [Department of Energy Engineering Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791 (Korea, Republic of); Al-Maadeed, M.A. [Center for Advanced Materials (CAM), Qatar University, 2713 Doha (Qatar); Belharouak, I., E-mail: ibelharouak@qf.org.qa [Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, P.O. Box 5825 Doha (Qatar)

    2016-06-15

    The new compounds NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} were synthesized by sol-gel method and their crystal structures were determined by using neutron powder diffraction data. These compounds were characterized by galvanometric cycling and cyclic voltammetry. NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} crystallize with a stuffed α-CrPO{sub 4}-type structure. The structure consists of a 3D-framework made of octahedra and tetrahedra that are sharing corners and/or edges generating channels along [100] and [010], in which the sodium atoms are located. Of significance, in the structures of NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} a statistical disorder Ni{sup 2+}/Cr{sup 3+} was observed on both the 8g and 4a atomic positions, whereas in NaCoCr{sub 2}(PO{sub 4}){sub 3} the statistical disorder Co{sup 2+}/Cr{sup 3+} was only observed on the 8g atomic position. When tested as negative electrode materials, NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} delivered specific capacities of 352, 385, and 368 mA h g{sup −1}, respectively, which attests to the electrochemical activity of sodium in these compounds. - Highlights: • NaCoCr{sub 2}(PO{sub 4}){sub 3}, NaNiCr{sub 2}(PO{sub 4}){sub 3}, and Na{sub 2}Ni{sub 2}Cr(PO{sub 4}){sub 3} were synthesized by sol-gel method. • The crystal structures were determined by using neutron powder diffraction data. • The three compounds crystallize with a stuffed α-CrPO{sub 4}-type structure. • The three compounds were tested as anodes in sodium-ion batteries. • Relatively high specific capacities were obtained for these compounds.

  5. Evaluation of NaX and NaY packed beds for chromium uptake from multicomponent solution

    Directory of Open Access Journals (Sweden)

    Maria Angélica Simões Dornellas de Barros

    2014-04-01

    Full Text Available In this paper the removal of chromium from Cr/Ca/Mg/K and Cr/Ca/Mg/K/Na solutions was investigated in NaX and NaY packed beds. The breakthrough curves presented some overshooting phenomena where chromium ions displaced the previous exchanged cations. Length of unused bed, overall mass transfer coefficient, operational ratio and dimensionless variance were obtained. According to such mass transfer parameters it was concluded that the chromium uptake is influenced by the competition and interaction of the entering ions. Such influences were verified through some differences in the dynamic selectivity obtained for each system. NaY seemed to have a higher affinity towards Cr3+ and its sites were more efficiently used in the ion exchange process.

  6. Water transport by the renal Na(+)-dicarboxylate cotransporter

    DEFF Research Database (Denmark)

    Meinild, A K; Loo, D D; Pajor, A M

    2000-01-01

    . This solute-coupled influx of water took place in the absence of, and even against, osmotic gradients. There was a strict stoichiometric relationship between Na(+), substrate, and water transport of 3 Na(+), 1 dicarboxylate, and 176 water molecules/transport cycle. These results indicate that the renal Na......This study investigated the ability of the renal Na(+)-dicarboxylate cotransporter, NaDC-1, to transport water. Rabbit NaDC-1 was expressed in Xenopus laevis oocytes, cotransporter activity was measured as the inward current generated by substrate (citrate or succinate), and water transport...... was monitored by the changes in oocyte volume. In the absence of substrates, oocytes expressing NaDC-1 showed an increase in osmotic water permeability, which was directly correlated with the expression level of NaDC-1. When NaDC-1 was transporting substrates, there was a concomitant increase in oocyte volume...

  7. Pioneering instrumentation aspects of NA60

    International Nuclear Information System (INIS)

    David, Andre

    2004-01-01

    NA60 is taking data with proton and heavy-ion beams at the CERN SPS. Although building up on previous experiments, the dimuon physics programme of NA60 places very demanding requirements on its new detectors, in terms of radiation tolerance, granularity and read-out electronics speed. We start by comparing dimuon detection strategies in NA60 with those of previous experiments. We then describe the new detectors used in NA60, placing particular emphasis on their technological pioneering aspects as well as on their contributions to the overall physics performance of the experiment

  8. Occlusion of 22Na+ and 86Rb+ in membrane-bound and soluble protomeric alpha beta-units of Na,K-ATPase

    International Nuclear Information System (INIS)

    Vilsen, B.; Andersen, J.P.; Petersen, J.; Jorgensen, P.L.

    1987-01-01

    In this work, we examined occlusion of 22 Na+ and 86 Rb+ in membranous and detergent-solubilized Na,K-ATPase from outer renal medulla. Optimum conditions for occlusion of 22 Na+ were provided by formation of the phosphorylated complex from the beta,gamma-bidentate complex of chromium (III) with ATP (CrATP). Release of occluded cations occurred at equally slow rates in soluble and membrane-bound Na,K-ATPase. Values of 22 Na+ occlusion as high as 11 nmol/mg of protein were measured, corresponding to 1.8-2.7 mol of Na+/mol of phosphorylated Na,K-ATPase as determined by 32 P incorporation from [gamma- 32 P]CrATP. Maximum capacity for phosphorylation from [gamma- 32 P]CrATP was 6 nmol/mg of protein and equal to capacities for binding of [48V]vanadate and [ 3 H]ouabain. The stoichiometry for occlusion of Rb+ was close to 2 Rb+ ions/phosphorylation site. In an analytical ultracentrifuge, the soluble Na+- or Rb+-occluded complexes showed sedimentation velocities (S20,w = 6.8-7.4) consistent with monomeric alpha beta-units. The data show that soluble monomeric alpha beta-units of Na,K-ATPase can occlude Rb+ or Na+ with the same stoichiometry as the membrane-bound enzyme. The structural basis for occlusion of cations in Na,K-ATPase is suggested to be the formation of a cavity inside a monomeric alpha beta-unit constituting the minimum protein unit required for active Na,K-transport

  9. Transcriptional regulators of Na, K-ATPase subunits

    Directory of Open Access Journals (Sweden)

    Zhiqin eLi

    2015-10-01

    Full Text Available The Na,K-ATPase classically serves as an ion pump creating an electrochemical gradient across the plasma membrane that is essential for transepithelial transport, nutrient uptake and membrane potential. In addition, Na,K-ATPase also functions as a receptor, a signal transducer and a cell adhesion molecule. With such diverse roles, it is understandable that the Na,K-ATPase subunits, the catalytic alpha-subunit, the beta-subunit and the FXYD proteins, are controlled extensively during development and to accommodate physiological needs. The spatial and temporal expression of Na,K-ATPase is partially regulated at the transcriptional level. Numerous transcription factors, hormones, growth factors, lipids and extracellular stimuli modulate the transcription of the Na,K-ATPase subunits. Moreover, epigenetic mechanisms also contribute to the regulation of Na,K-ATPase expression. With the ever growing knowledge about diseases associated with the malfunction of Na,K-ATPase, this review aims at summarizing the best-characterized transcription regulators that modulate Na,K-ATPase subunit levels. As abnormal expression of Na,K-ATPase subunits have been observed in many carcinoma, we will also discuss transcription factors that are associated with epithelial-to-mesenchymal transition, a crucial step in the progression of many tumors to malignant disease.

  10. Creation of the NaSCoRD Database

    Energy Technology Data Exchange (ETDEWEB)

    Denman, Matthew R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jankovsky, Zachary Kyle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stuart, William [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    This report was written as part of a United States Department of Energy (DOE), Office of Nuclear Energy, Advanced Reactor Technologies program funded project to re-create the capabilities of the legacy Centralized Reliability Database Organization (CREDO) database. The CREDO database provided a record of component design and performance documentation across various systems that used sodium as a working fluid. Regaining this capability will allow the DOE complex and the domestic sodium reactor industry to better understand how previous systems were designed and built for use in improving the design and operations of future loops. The contents of this report include: overview of the current state of domestic sodium reliability databases; summary of the ongoing effort to improve, understand, and process the CREDO information; summary of the initial efforts to develop a unified sodium reliability database called the Sodium System Component Reliability Database (NaSCoRD); and explain both how potential users can access the domestic sodium reliability databases and the type of information that can be accessed from these databases.

  11. Nematic fluctuations in iron arsenides NaFeAs and LiFeAs probed by 75As NMR

    Science.gov (United States)

    Toyoda, Masayuki; Kobayashi, Yoshiaki; Itoh, Masayuki

    2018-03-01

    75As NMR measurements have been made on single crystals to study the nematic state in the iron arsenides NaFeAs, which undergoes a structural transition from a high-temperature (high-T ) tetragonal phase to a low-T orthorhombic phase at Ts=57 K and an antiferromagnetic transition at TN=42 K, and LiFeAs having a superconducting transition at Tc=18 K. We observe the in-plane anisotropy of the electric field gradient η even in the tetragonal phase of NaFeAs and LiFeAs, showing the local breaking of tetragonal C4 symmetry. Then, η is found to obey the Curie-Weiss (CW) law as well as in Ba (Fe1-xCox) 2As2 . The good agreement between η and the nematic susceptibility obtained by electronic Raman spectroscopy indicates that η is governed by the nematic susceptibility. From comparing η in NaFeAs and LiFeAs with η in Ba (Fe1-xCox) 2As2 , we discuss the carrier-doping dependence of the nematic susceptibility. The spin contribution to nematic susceptibility is also discussed from comparing the CW terms in η with the nuclear spin-lattice relaxation rate divided by temperature 1 /T1T . Finally, we discuss the nematic transition in the paramagnetic orthorhombic phase of NaFeAs from the in-plane anisotropy of 1 /T1T .

  12. SPOLNO NADLEGOVANJE NA DELOVNEM MESTU

    OpenAIRE

    Rubič, Gašper

    2016-01-01

    V diplomskem delu smo v uvodu predstavili problem spolnega nadlegovanja na delovnem mestu in predstavili podjetje TEKSTIL d.d. V nadaljevanju smo z anketo raziskali, ali problem spolnega nadlegovanja na delovnem mestu v obravnavanem podjetju obstaja in če, kako se nanj odziva okolje. V teoretičnem delu smo nadaljevali in predstavili definicijo spolnega nadlegovanja, ki je kakršna koli oblika nezaželenega verbalnega in neverbalnega ali fizičnega ravnanja spolne narave z učinkom ali nameno...

  13. Invisible nuclear; converting nuclear

    International Nuclear Information System (INIS)

    Park, Jongmoon

    1993-03-01

    This book consists of 14 chapters which are CNN era and big science, from East and West to North and South, illusory nuclear strategy, UN and nuclear arms reduction, management of armaments, advent of petroleum period, the track of nuclear power generation, view of energy, internationalization of environment, the war over water in the Middle East, influence of radiation and an isotope technology transfer and transfer armament into civilian industry, the end of nuclear period and the nuclear Nonproliferation, national scientific and technological power and political organ and executive organ.

  14. Photodesorption of Na atoms from rough Na surfaces

    DEFF Research Database (Denmark)

    Balzer, Frank; Gerlach, R.; Manson, J.R.

    1997-01-01

    We investigate the desorption of Na atoms from large Na clusters deposited on dielectric surfaces. High-resolution translational energy distributions of the desorbing atoms are determined by three independent methods, two-photon laser-induced fluorescence, as well as single-photon and resonance......-enhanced two-photon ionization techniques. Upon variation of surface temperature and for different substrates (mica vs lithium fluoride) clear non-Maxwellian time-of-flight distributions are observed with a cos θ angular dependence and most probable kinetic energies below that expected of atoms desorbing from...... atoms are scattered by surface vibrations. Recent experiments providing time constants for the decay of the optical excitations in the clusters support this model. The excellent agreement between experiment and theory indicates the importance of both absorption of the laser photons via direct excitation...

  15. Evaluation of {sup 23}Na(n,2n){sup 22}Na reaction cross-sections

    Energy Technology Data Exchange (ETDEWEB)

    Manokhin, V N [Institute of Physics and Power Engineering, Obninsk (Russian Federation)

    1997-06-01

    Using available experimental data and (n,2n) excitation function systematics {sup 23}Na(n,2n){sup 22}Na reaction cross-sections were evaluated for energies ranging from the reaction threshold to 20 MeV. (author). 21 refs, 1 fig., 2 tabs.

  16. Formation of hydroxyl groups and exchange with deuterium on NaHX and NaHY zeolites

    International Nuclear Information System (INIS)

    Kubelkova, L.; Novakova, J.

    1976-01-01

    Deammoniation and dehydroxylation of Na(NH 4 )X and Na(NH 4 )Y zeolites were compared. With the X type, both processes overlapped and proceeded more easily than with the Y type. Both H forms contained structural OH groups and hydroxyls denoted as SiOH, to which the 3740 cm -1 band in the IR spectrum was assigned. In addition, the NaHX zeolite contained OH groups characterized by the 3700 and 3600 cm -1 bands. Certain differences in the behaviour of NaHX and NaHY zeolites during deammoniation and dehydroxylation might be attributed to the presence of ''non-localizable'' H atoms. The active sites for the D 2 -OH exchange were probably formed during dehydroxylation. Hydrogen in SiOH groups was replaced by deuterium in both zeolite types more slowly than H atoms in other OH groups, which influenced the kinetic variations in the gaseous phase. The presence of water in the gaseous phase affected the kinetics and could distort the determination of the number of H atoms bound in the zeolites. (author)

  17. OGLAŠEVANJE NA SOCIALNEM OMREŽJU FACEBOOK, NA PRIMERU SPLETICNA.SI

    OpenAIRE

    Reisman, Nina

    2011-01-01

    Internet je od svojega razvoja dolgo časa obstajal kot prostor za enostransko komunikacijo. Isto se je dogajalo na televiziji, radiu in časopisih, kjer je javnost sprejemala informacije, ki jih je nekdo pripravil. Tradicionalni mediji so hitro doumeli, da takšna vrsta komunikacije ni naravna in ne predstavlja najboljšega ohranjanja gledalcev in poslušalcev. Začela se je uporabljati dvosmerna komunikacija. Trenutno v svetu najbolje poznan primer dvosmerne komunikacije je socialno omrežje F...

  18. FTIR spectra of the solid solutions (Na0.88K0.12)VO3, (Na0.5K0.5)VO3, and Na(V0.66P0.34)O3

    Science.gov (United States)

    de Waal, D.; Heyns, A. M.

    1992-03-01

    It is known that three different solid solutions, (Na0.88K0.12)VO3, (Na0.5K0.5)VO3 and Na(V0.66P0.34)O3, form in the (Na,K)(V,P)O3 system. These compounds all have monoclinic crystal structures similar to the pure alkali metal metavanadates containing small cations, e.g. Li+ and Na+ (Space group C2/c). Metavanadates with large cations like K+, Rb+, C+s and NH+4 form orthorhombic crystals, space group Pbcm. All those are structurally related to the silicate pyroxenes. Na(V0.66P0.34)O3 and (Na0.88K0.12)VO3 have the same modified diopside structure as (alpha) - NaVO3 while (Na0.5K0.5)VO3 adopts the true diopside structure. The infrared spectra of the three solid solutions are reported here in comparison with those of (alpha) -NaVO3 and KVO3. The results are also correlated with those obtained in two independent high pressure Raman studies of NH4VO3 and RbVO3 as the introduction of a larger cation like K+ should increase the pressure in the structure.

  19. Medetomidīna un detomidīna hidrogēnhlorīdu struktūra noteikšana

    OpenAIRE

    Smuļko, Irina

    2012-01-01

    Medetomidīna un detomidīna hidrogēnhlorīdu struktūras noteikšana. Smuļko I., zinātniskais vadītājs Dr. ķīm., asoc. prof. Actiņš A. Maģistra darbs, 52 lappuses, 37 attēli, 6 tabulas, 29 literatūras avoti. Latviešu valodā. Maģistra darbā pētītas farmaceitiski aktīvās vielas – medetomidīna un detomidīna hidrogēnhlorīdi. Veikti mēģinājumi detomidīna bezūdens formas un monohidrāta struktūras noteikšanai, kā arī medetomidīna bezūdens formu A un B struktūras noteikšanai. Struktūras noteikšanai iz...

  20. NAKUPOVANJE NA SPLETU

    OpenAIRE

    Visenjak, Monika

    2013-01-01

    Nakupovanje na spletu je prihodnost poslovanja. Za podjetja pomeni manjše stroške, lažje prilagajanje tržnim pogojem. Hitreje lahko razvijajo odnose in analizirajo uporabnike, saj jim je dan dostop o nakupnih podatkih uporabnika. Za potrošnike je nakupovanje na spletu možnost hitrega, preprostega in učinkovitega nakupovanja od doma ali pisarne. Pomembno je, da se seznanijo z vsemi informacijami in pogoji spletnih trgovin, saj se lahko le tako izognejo nezadovoljstvu ob nakupu v spletni trgovi...

  1. Institute for Nuclear Research and Nuclear Energy and Nuclear Science

    International Nuclear Information System (INIS)

    Stamenov, J.

    2004-01-01

    The Institute for Nuclear Research and Nuclear Energy (INRNE) of the Bulgarian Academy of Sciences is the leading Bulgarian Institute for scientific investigations and applications of nuclear science. The main Institute's activities in the field of elementary particles and nuclear physics, high energy physics and nuclear energy, radiochemistry, radioecology, radioactive wastes treatment, monitoring of the environment, nuclear instruments development ect. are briefly described. Several examples for: environmental radiation monitoring; monitoring of the radioactivity and heavy metals in aerosols, 99m Tc clinical use, Boron Neutron Capture Therapy application of IRT-2000 Research Reactor, neutron fluence for reactor vessel embrittlement, NPP safety analysis, nuclear fuel modelling are also presented

  2. The Na+ transporter, TaHKT1;5-D, limits shoot Na+ accumulation in bread wheat

    KAUST Repository

    Byrt, Caitlin Siobhan

    2014-10-01

    Bread wheat (Triticum aestivum L.) has a major salt tolerance locus, Kna1, responsible for the maintenance of a high cytosolic K+/Na+ ratio in the leaves of salt stressed plants. The Kna1 locus encompasses a large DNA fragment, the distal 14% of chromosome 4DL. Limited recombination has been observed at this locus making it difficult to map genetically and identify the causal gene. Here, we decipher the function of TaHKT1;5-D, a candidate gene underlying the Kna1 locus. Transport studies using the heterologous expression systems Saccharomyces cerevisiae and Xenopus laevis oocytes indicated that TaHKT1;5-D is a Na+-selective transporter. Transient expression in Arabidopsis thaliana mesophyll protoplasts and in situ polymerase chain reaction indicated that TaHKT1;5-D is localised on the plasma membrane in the wheat root stele. RNA interference-induced silencing decreased the expression of TaHKT1;5-D in transgenic bread wheat lines which led to an increase in the Na+ concentration in the leaves. This indicates that TaHKT1;5-D retrieves Na+ from the xylem vessels in the root and has an important role in restricting the transport of Na+ from the root to the leaves in bread wheat. Thus, TaHKT1;5-D confers the essential salinity tolerance mechanism in bread wheat associated with the Kna1 locus via shoot Na+ exclusion and is critical in maintaining a high K+/Na+ ratio in the leaves. These findings show there is potential to increase the salinity tolerance of bread wheat by manipulation of HKT1;5 genes.

  3. The Na+ transporter, TaHKT1;5-D, limits shoot Na+ accumulation in bread wheat

    KAUST Repository

    Byrt, Caitlin Siobhan; Xu, Bo; Krishnan, Mahima; Lightfoot, Damien; Athman, Asmini; Jacobs, Andrew Keith; Watson-Haigh, Nathan S.; Plett, Darren; Munns, Rana; Tester, Mark A.; Gilliham, Matthew

    2014-01-01

    Bread wheat (Triticum aestivum L.) has a major salt tolerance locus, Kna1, responsible for the maintenance of a high cytosolic K+/Na+ ratio in the leaves of salt stressed plants. The Kna1 locus encompasses a large DNA fragment, the distal 14% of chromosome 4DL. Limited recombination has been observed at this locus making it difficult to map genetically and identify the causal gene. Here, we decipher the function of TaHKT1;5-D, a candidate gene underlying the Kna1 locus. Transport studies using the heterologous expression systems Saccharomyces cerevisiae and Xenopus laevis oocytes indicated that TaHKT1;5-D is a Na+-selective transporter. Transient expression in Arabidopsis thaliana mesophyll protoplasts and in situ polymerase chain reaction indicated that TaHKT1;5-D is localised on the plasma membrane in the wheat root stele. RNA interference-induced silencing decreased the expression of TaHKT1;5-D in transgenic bread wheat lines which led to an increase in the Na+ concentration in the leaves. This indicates that TaHKT1;5-D retrieves Na+ from the xylem vessels in the root and has an important role in restricting the transport of Na+ from the root to the leaves in bread wheat. Thus, TaHKT1;5-D confers the essential salinity tolerance mechanism in bread wheat associated with the Kna1 locus via shoot Na+ exclusion and is critical in maintaining a high K+/Na+ ratio in the leaves. These findings show there is potential to increase the salinity tolerance of bread wheat by manipulation of HKT1;5 genes.

  4. Nuclear power and nuclear weapons

    International Nuclear Information System (INIS)

    Vaughen, V.C.A.

    1983-01-01

    The proliferation of nuclear weapons and the expanded use of nuclear energy for the production of electricity and other peaceful uses are compared. The difference in technologies associated with nuclear weapons and nuclear power plants are described

  5. Osmotic and ionic effects of NaCl and Na2SO4 salinity on Phragmites australis

    DEFF Research Database (Denmark)

    Pagter, Majken; Bragato, Claudia; Malagoli, Mario

    2009-01-01

    Osmotic and ion-specific effects of NaCl and Na2SO4 on Phragmites australis (Cav.) Trin ex. Steud. were investigated in a laboratory experiment by examining effects of iso-osmotic solutions of NaCl and Na2SO4 on growth, osmolality of cell sap, proline content, elemental composition and gas exchange....... Plants were supplied with a control standard nutrient solution (Ψ = -0.09 MPa) or solutions of NaCl or Na2SO4 at water potentials of -0.50, -1.09 or -1.74 MPa. Salt treatments increased root concentrations of Na and S or Cl, whereas P. australis had efficient mechanisms for exclusion of Na and S...... and partly Cl ions from the leaves. Incomplete exclusion of Cl from the leaves may affect aboveground biomass production, which was significantly more reduced by NaCl than Na2SO4. Stomatal conductance was negatively influenced by decreasing water potentials caused by NaCl or Na2SO4, implying that a non...

  6. Polarization and collision velocity dependence of associative ionization in cold Na (3p)-Na(3p) collisions

    NARCIS (Netherlands)

    Meijer, H.A.J.

    1990-01-01

    We studied the polarization dependence of the associative ionization (AI) process Na(3p) + Na(3p) → Na2+ at collision velocities between 100 and 700 m/s (5 and 200 K), using linearly and circularly polarized light for the excitation. We found that the polarization dependence varies strongly in the

  7. Evidence for dawsonite in Hanford high-level nuclear waste tanks.

    Science.gov (United States)

    Reynolds, Jacob G; Cooke, Gary A; Herting, Daniel L; Warrant, R Wade

    2012-03-30

    Gibbsite [Al(OH)(3)] and boehmite (AlOOH) have long been assumed to be the most prevalent aluminum-bearing minerals in Hanford high-level nuclear waste sludge. The present study shows that dawsonite [NaAl(OH)(2)CO(3)] is also a common aluminum-bearing phase in tanks containing high total inorganic carbon (TIC) concentrations and (relatively) low dissolved free hydroxide concentrations. Tank samples were probed for dawsonite by X-ray Diffraction (XRD), Scanning Electron Microscopy with Energy Dispersive Spectrometry (SEM-EDS) and Polarized Light Optical Microscopy. Dawsonite was conclusively identified in four of six tanks studied. In a fifth tank (AN-102), the dawsonite identification was less conclusive because it was only observed as a Na-Al bearing phase with SEM-EDS. Four of the five tank samples with dawsonite also had solid phase Na(2)CO(3) · H(2)O. The one tank without observable dawsonite (Tank C-103) had the lowest TIC content of any of the six tanks. The amount of TIC in Tank C-103 was insufficient to convert most of the aluminum to dawsonite (Al:TIC mol ratio of 20:1). The rest of the tank samples had much lower Al:TIC ratios (between 2:1 and 0.5:1) than Tank C-103. One tank (AZ-102) initially had dawsonite, but dawsonite was not observed in samples taken 15 months after NaOH was added to the tank surface. When NaOH was added to a laboratory sample of waste from Tank AZ-102, the ratio of aluminum to TIC in solution was consistent with the dissolution of dawsonite. The presence of dawsonite in these tanks is of significance because of the large amount of OH(-) consumed by dawsonite dissolution, an effect confirmed with AZ-102 samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Erythrocyte Na+/K+ ATPase activity measured with sup 23 Na NMR

    Energy Technology Data Exchange (ETDEWEB)

    Ouwerkerk, R.; van Echteld, C.J.; Staal, G.E.; Rijksen, G. (University Hospital, Utrecht (Netherland))

    1989-11-01

    A {sup 23}Na NMR assay for measurement of erythrocyte Na+/K+ ATPase activity is presented. Using the nonpermeant shift reagent dysprosium tripolyphosphate the signals of intra- and extracellular sodium are separated, enabling measurement of sodium fluxes nondestructively, without the need to physically separate the cells from their environment. By increasing membrane permeability with nystatin we have shown that the assay allows the detection of differences in membrane permeability. With low doses of nystatin the ouabain-sensitive sodium flux increased more than twofold. With high doses of nystatin the Na+/K+ pump could not prevent an almost total equilibration of intra- and extracellular sodium. All sodium that entered the cells remained NMR visible, proving that sodium influx can be measured quantitatively. {sup 31}P NMR spectra taken before and after the assay revealed a slight acidification of the cells and no significant change in ATP concentration. No evidence of Dy3+ entering the cell was observed.

  9. Nuclear safety. Seguranca nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Aveline, A [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Inst. de Fisica

    1981-01-01

    What is nuclear safety Is there any technical way to reduce risks Is it possible to put them at reasonable levels Are there competitiveness and economic reliability to employ the nuclear energy by means of safety technics Looking for answers to these questions the author describes the sources of potential risks to nuclear reactors and tries to apply the answers to the Brazilian Nuclear Programme. (author).

  10. Molecular dynamics investigation of Na+ in Na2Ni2TeO6

    International Nuclear Information System (INIS)

    Sau, Kartik; Kumar, P. Padma

    2014-01-01

    An inter-atomic potential for Na 2 Ni 2 TeO 6 in the Parrinello- Rahman-Vashishta (PRV) model is parameterized empirically. The potential reproduces variety of structural and transport properties of that material in good agreement with recent experimental results. The study provides fresh insights on the migration channels and mechanism of Na + in the system

  11. Efeito do plasma de oxigênio na dentina previamente exposta ao NaOCl

    Directory of Open Access Journals (Sweden)

    Maíra do PRADO

    Full Text Available Resumo Introdução O tratamento de plasma é uma tecnologia eficaz que pode manter as propriedades internas dos materiais inalteradas após o tratamento, modificando apenas a superfície. Objetivo Avaliar o efeito do plasma de oxigênio na dentina previamente exposta ao NaOCl 6%. Material e método Foram utilizados 60 incisivos bovinos. A coroa foi removida, a raiz foi dividida e as faces planificadas, totalizando 120 segmentos referentes ao terço cervical. As amostras foram divididas em dois grupos: controle (imersa em NaOCl 6%, lavada com água destilada, seca, imersa em EDTA 17%, lavada e seca e plasma de oxigênio (após tratamento descrito no grupo controle, plasma de oxigênio foi aplicado por 30 s. As amostras foram avaliadas qualitativamente em relação à topografia por microscopia eletrônica de varredura, utilizando-se microfotografias com ampliação de 1.000×. O goniômetro Ramé-hart foi utilizado para a mensuração do ângulo de contato entre as superfícies e as seguintes soluções foram utilizadas: água, etilenoglicol e di-iodometano. Em seguida, a energia de superfície, representada pelas componentes polar e dispersiva, foi calculada. Avaliou-se também o escoamento dos cimentos Pulp Canal Sealer EWT (PCS e Real Sal SE (RS na superfície dentinária. Os dados foram analisados estatisticamente utilizando os testes Kruskal-Wallis e Mann-Whitney U (p<0,05. Resultado O tratamento com plasma levou à formação de uma camada semelhante à smear layer na superfície dentinária. Este tratamento levou a um aumento da energia de superfície e da componente polar, favorecendo a hidrofilicidade da superfície. Entretanto, desfavoreceu o escoamento do cimento PCS e não influenciou no escoamento do cimento RS. Conclusão O plasma de oxigênio ocasionou mudanças topográficas na superfície dentinária, favorecendo a hidrofilicidade desta. Contudo, não favoreceu o escoamento dos cimentos endodônticos na dentina.

  12. Phase formation in the systems ZrO2-H2SO4-Na2SO4 (NaCl)-H2O

    International Nuclear Information System (INIS)

    Sozinova, Yu.P.; Motov, D.L.; Rys'kina, M.P.

    1988-01-01

    Formation of solid phases in the systems ZrO 2 - H 2 SO 4 - Na 2 SO 4 (NaCl) - H 2 O at 25 and 75 deg C is studied. Three basic Na 2 Zr(OH) 2 (SO 4 ) 2 x (0.2 - 0.4)H 2 O, NaZrOH(SO 4 ) 2 x H 2 O, NaZrO 0.5 (OH) 2 SO 4 x 2H 2 O and three normal sodium sulfatozirconates Na 2 Zr(SO 4 ) 3 x 3H 2 O, Na 4 Zr(SO 4 ) 4 x 3H 2 O, Na 6 Zr(SO 4 ) 5 x 4H 2 O have been isolated, their solubility and crystal optical properties are determined

  13. Spectroscopic calculation of the excited electronic states with spin orbit effect of the molecule NaCs

    International Nuclear Information System (INIS)

    Bleik, S.; Korek, M.; Allouche, A.R.

    2004-01-01

    Full text.The existence of new experimental data on the alkali dimers has stimulated theoretical approaches, necessary to provide predictions accurate enough to be useful for interpretation and evenly for guidance of experiments. With the aim of improving the accuracy of predictions we will perform a theoretical study of the electronic structure of the molecule NaCs using a method mainly in the way by which core-valence effects are taken into account. To investigate the electronic structure of NaCs we will use the package CIPSI (Configuration Interaction by Perturbation of a multiconfiguration wave function Selected Interactively) of the Laboratoire de Physique Quantique (Toulouse, France). The atoms Na and Cs will be treated through non-empirical effective one electron core potentials of Durand and Barthelat type. Molecular orbitals for NaCs will be derived from Self Consistent field Calculations (SCF) and full valence Configuration Interaction (IC) calculations. A core-core interaction more elaborated than the usual approximation 1/R will be taken into account as the sum of an exponential repulsive term plus a long range dispersion term approximated by the well known London formula. Potential energy calculations will be performed for different molecular states, for numerous values of the inter-nuclear distance R in a wide range. Spectroscopic constants have been derived for the bound states with regular shape. A ro vibrational study have been performed for the ground states with a calculation of the rotational and centrifugal distortion constants. A calculation for the transition dipole moment and matrix elements have been done for the bound states

  14. Modification of NaK (Na and K) dissolution device at the L.E.C.I

    International Nuclear Information System (INIS)

    Mansard, Bernard; Ducas, Serge; Riviere, Michel

    1969-12-01

    As three NaK dissolution devices had been operated since 1965 and as irradiation assemblies with a greater capacity (2 to 3 times) are now to be used, the modification of these dissolution devices is addressed. This requires a better control of the dissolution reaction (the NaK + alcohol reaction is highly exothermic and results in an effervescence which requires a greater volume). The objectives are therefore to delay the dissolution, to trigger it, to stop it, to control it at will, and to release heat. The new device is then described with its vessel, its cap, its ball valve, and its two tight sleeves. The operation principle is described, as well as the NaK draining process, and the NaK dissolution. Safety, time saving and raw matter saving issues are finally outlined

  15. OGLAŠEVANJE NA FACEBOOKU V SLOVENIJI

    OpenAIRE

    Dobnik, Monja

    2013-01-01

    Danes so zahvaljujoč napredni mobilni tehnologiji družbena omrežja z nami na vsakem koraku. Facebook (FB) se po priljubljenosti uvršča v sam vrh družbenih omrežij in glede na to, da ga uporablja že več kot milijarda zemljanov, ponuja tudi odlične trg za oglaševanje. To so ugotovili tudi slovenski podjetniki. V diplomski nalogi je predstavljeno, kako na FB oglašujejo nekatera slovenska podjetja, s pomočjo spletnega vprašalnika pa je ugotovljeno tudi, kaj o oglasih na FB menijo njegovi uporabni...

  16. Myocardial Na,K-ATPase: Clinical aspects

    Science.gov (United States)

    Kjeldsen, Keld

    2003-01-01

    The specific binding of digitalis glycosides to Na,K-ATPase is used as a tool for Na,K-ATPase quantification with high accuracy and precision. In myocardial biopsies from patients with heart failure, total Na,K-ATPase concentration is decreased by around 40%; a correlation exists between a decrease in heart function and a decrease in Na,K-ATPase concentration. During digitalization, around 30% of remaining pumps are occupied by digoxin. Myocardial Na,K-ATPase is also influenced by other drugs used for the treatment of heart failure. Thus, potassium loss during diuretic therapy has been found to reduce myocardial Na,K-ATPase, whereas angiotensin-converting enzyme inhibitors may stimulate Na,K pump activity. Furthermore, hyperaldosteronism induced by heart failure has been found to decrease Na,K-ATPase activity. Accordingly, treatment with the aldosterone antagonist, spironolactone, may also influence Na,K-ATPase activity. The importance of Na,K pump modulation with heart disease, inhibition in digitalization and other effects of medication should be considered in the context of sodium, potassium and calcium regulation. It is recommended that digoxin be administered to heart failure patients who, after institution of mortality-reducing therapy, still have heart failure symptoms, and that the therapy be continued if symptoms are revealed or reduced. Digitalis glycosides are the only safe inotropic drugs for oral use that improve hemodynamics in heart failure. An important aspect of myocardial Na,K pump affection in heart disease is its influence on extracellular potassium (Ke) homeostasis. Two important aspects should be considered: potassium handling among myocytes, and effects of potassium entering the extracellular space of the heart via the bloodstream. It should be noted that both of these aspects of Ke homeostasis are affected by regulatory aspects, eg, regulation of the Na,K pump by physiological and pathophysiological conditions, as well as by medical

  17. Advancement of technology towards developing Na-ion batteries

    Science.gov (United States)

    Jamesh, Mohammed Ibrahim; Prakash, A. S.

    2018-02-01

    The Na-ion-batteries are considered much attention for the next-generation power-sources due to the high abundance of Na resources that lower the cost and become the alternative for the state of the art Li-ion batteries in future. In this review, the recently reported potential cathode and anode candidates for Na-ion-batteries are identified in-light-of-their high-performance for the development of Na-ion-full-cells. Further, the recent-progress on the Na-ion full-cells including the strategies used to improve the high cycling-performance (stable even up-to 50000 cycles), operating voltage (even ≥ 3.7 V), capacity (>350 mAhg-1 even at 1000 mAg-1 (based-on-mass-of-the-anode)), and energy density (even up-to 400 Whkg-1) are reviewed. In addition, Na-ion-batteries with the electrodes containing reduced graphene oxide, and the recent developments on symmetric Na-ion-batteries are discussed. Further, this paper identifies the promising Na-ion-batteries including the strategies used to assemble full-cell using hard-carbon-anodes, Na3V2(PO4)3 cathodes, and other-electrode-materials. Then, comparison between aqueous and non-aqueous Na-ion-batteries in terms of voltage and energy density has been given. Later, various types of electrolytes used for Na-ion-batteries including aqueous, non-aqueous, ionic-liquids and solid-state electrolytes are discussed. Finally, commercial and technological-developments on Na-ion-batteries are provided. The scientific and engineering knowledge gained on Na-ion-batteries afford conceivable development for practical application in near future.

  18. Negative electrodes for Na-ion batteries.

    Science.gov (United States)

    Dahbi, Mouad; Yabuuchi, Naoaki; Kubota, Kei; Tokiwa, Kazuyasu; Komaba, Shinichi

    2014-08-07

    Research interest in Na-ion batteries has increased rapidly because of the environmental friendliness of sodium compared to lithium. Throughout this Perspective paper, we report and review recent scientific advances in the field of negative electrode materials used for Na-ion batteries. This paper sheds light on negative electrode materials for Na-ion batteries: carbonaceous materials, oxides/phosphates (as sodium insertion materials), sodium alloy/compounds and so on. These electrode materials have different reaction mechanisms for electrochemical sodiation/desodiation processes. Moreover, not only sodiation-active materials but also binders, current collectors, electrolytes and electrode/electrolyte interphase and its stabilization are essential for long cycle life Na-ion batteries. This paper also addresses the prospect of Na-ion batteries as low-cost and long-life batteries with relatively high-energy density as their potential competitive edge over the commercialized Li-ion batteries.

  19. The use of genetic algorithms with niching methods in nuclear reactor related problems; A utilizacao dos metodos de nichos dos algoritmos geneticos na otimizacao de problemas de reatores nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Sacco, Wagner Figueiredo

    2000-03-01

    Genetic Algorithms (GAs) are biologically motivated adaptive systems which have been used, with good results, in function optimization. However, traditional GAs rapidly push an artificial population toward convergence. That is, all individuals in the population soon become nearly identical. Niching Methods allow genetic algorithms to maintain a population of diverse individuals. GAs that incorporate these methods are capable of locating multiple, optimal solutions within a single population. The purpose of this study is to test existing niching techniques and two methods introduced herein, bearing in mind their eventual application in nuclear reactor related problems, specially the nuclear reactor core reload one, which has multiple solutions. Tests are performed using widely known test functions and their results show that the new methods are quite promising, specially in real world problems like the nuclear reactor core reload. (author)

  20. Corpo e sexualidade na gravidez

    Directory of Open Access Journals (Sweden)

    Natalúcia Matos Araújo

    2012-06-01

    Full Text Available Estudo etnográfico que teve como objetivo compreender como as gestantes vivenciam os processos fisiológicos do seu corpo durante a gestação e a sua repercussão na sexualidade. A pesquisa envolveu sete mulheres residentes em bairro popular de São Paulo. Na coleta de dados, utilizou-se observação participante e entrevista com questões norteadoras. Os dados foram apresentados na forma de narrativa e posteriormente organizados nas categorias: Percebendo as transformações corporais; Convivendo com as mudanças no corpo; Sentimentos e sensações na vida sexual durante a gestação e imaginando o corpo e a sexualidade após a gestação. As mulheres referiram-se às transformações do corpo como desconfortos e expressaram a preocupação de que fossem definitivas. Expressaram o desejo de que, após o parto, o corpo volte a ser como era e que volte a sentir desejo sexual. O reconhecimento destes fatos constitui-se numa ferramenta primordial na adequação das práticas profissionais.