WorldWideScience

Sample records for mes sr user

  1. Methodological development for 87Sr/86Sr measurement in olive oil and preliminary discussion of its use for geographical traceability of PDO Nîmes (France).

    Science.gov (United States)

    Medini, Salim; Janin, Myriam; Verdoux, Patrick; Techer, Isabelle

    2015-03-15

    The lack of a geographical identification protocol for olive oils can lead to fraud and health risks. As some works call for Sr isotopes for the geographical identification of agri-food products, this study focus on the feasibility of extracting Sr from olive oils for isotopic measurements by TIMS. In fact, existing protocols for purification of Sr are unsuitable for lipid matrix. The defined protocol is applied to samples of PDO Nîmes olive oil. The accuracy of the extraction procedure is tested against isotopic standards. The values obtained are in conformity with NIST certified values. This consistency demonstrates that no modification of (87)Sr/(86)Sr ratio is brought about by this protocol. Consequently, the method is preliminary used on PDO Nîmes and Moroccan oils to evaluate the feasibility of a discriminant Sr signature on the two geographical products. This study provides promising results for the geographical discrimination and identification of PDO olive oils. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Energy efficient MES. 39 vedors in comparison; Energieeffiziente MES. 39 Anbieter im Vergleich

    Energy Technology Data Exchange (ETDEWEB)

    Theuer, Hanna; Leo, Anne-Kathrin [Potsdam Univ. (Germany). Lehrstuhl fuer Wirtschaftsinformatik und Electronic Government

    2012-07-01

    Due to increased legal restrictions, higher energy costs as well as the growing energy consciousness of the population, in recent years the energy-efficient production has increased in importance. Manufacturing Execution Systems (MES) have a high potential in the recognition of potential savings and in the creation of solutions due to their direct application in production. The Center for Enterprise Research (Potsdam, Federal Republic of Germany) has queried many MES vendors about their functionality as well as the possibilities of the systems in the field of energy efficiency. Answers to 39 systems are received.

  3. Metagenome-Assembled Genome Sequences of Acetobacterium sp. Strain MES1 and Desulfovibrio sp. Strain MES5 from a Cathode-Associated Acetogenic Microbial Community.

    Science.gov (United States)

    Ross, Daniel E; Marshall, Christopher W; May, Harold D; Norman, R Sean

    2017-09-07

    Draft genome sequences of Acetobacterium sp. strain MES1 and Desulfovibrio sp. strain MES5 were obtained from the metagenome of a cathode-associated community enriched within a microbial electrosynthesis system (MES). The draft genome sequences provide insight into the functional potential of these microorganisms within an MES and a foundation for future comparative analyses. Copyright © 2017 Ross et al.

  4. Portuaires et autres poèmes

    OpenAIRE

    Sévry, Jean

    2015-01-01

    Pour Paul Bensimon, affectueusement P O R T U A I R E S Longs dédales lents cheminementsRéseaux patiemment tissésDans l’écheveau de tes doigtsIl fait bon se réfugier Algues de l’accueil cordialité du corailRécifs enchanteurs eaux limpidesCorps libres nudités muscles pleinsNappes glauques où se perdent mes palmesPoisson voilà que je tresse mes écaillesEt mes nageoires effleurent tes pétales Départs sans idée d’escalesAncres légères chaînes détachéesBonheur du port auberges mitonnéesEmbarquemen...

  5. A methodology for Manufacturing Execution Systems (MES) implementation

    Science.gov (United States)

    Govindaraju, Rajesri; Putra, Krisna

    2016-02-01

    Manufacturing execution system is information systems (IS) application that bridges the gap between IS at the top level, namely enterprise resource planning (ERP), and IS at the lower levels, namely the automation systems. MES provides a media for optimizing the manufacturing process as a whole in a real time basis. By the use of MES in combination with the implementation of ERP and other automation systems, a manufacturing company is expected to have high competitiveness. In implementing MES, functional integration -making all the components of the manufacturing system able to work well together, is the most difficult challenge. For this, there has been an industry standard that specifies the sub-systems of a manufacturing execution systems and defines the boundaries between ERP systems, MES, and other automation systems. The standard is known as ISA-95. Although the advantages from the use of MES have been stated in some studies, not much research being done on how to implement MES effectively. The purpose of this study is to develop a methodology describing how MES implementation project should be managed, utilising the support of ISA- 95 reference model in the system development process. A proposed methodology was developed based on a general IS development methodology. The developed methodology were then revisited based on the understanding about the specific charateristics of MES implementation project found in an Indonesian steel manufacturing company implementation case. The case study highlighted the importance of applying an effective requirement elicitation method during innitial system assessment process, managing system interfaces and labor division in the design process, and performing a pilot deployment before putting the whole system into operation.

  6. Elaboration, microstructure, propriétés électriques et magnétiques de matériaux textures dans les systèmes Nd-Ce-Cu-O et Bi-Sr-Ca-Cu-O

    Science.gov (United States)

    Dhalenne, G.; Trouilleux, L.; Jegoudez, J.; Revcolevschi, A.; Monod, P.; Kormann, R.; Ganne, J. P.; Motohira, N.; Kitazawa, K.

    1991-11-01

    Superconducting textured materials were grown from the melt by a floating zone technique in the Nd-Ce-Cu-O and Bi-Sr-Ca-Cu-O systems. The influence of growth conditions and starting compositions on the microstructures and phase composition of the samples were studied by optical microscopy under polarized light, electron microprobe analysis and X-ray diffraction. The superconducting properties of these samples were examined by both electrical resistivity and magnetic measurements. A very strong influence of the microstructure on the superconducting properties as well as a magnetic and electrical anisotropy were shown. In the case of the Bi-Sr-Ca-Cu-O system, critical current densities ranging from 1 600 to 3 000 A.cm^{-2} were measured at 77 K. Des matériaux supraconducteurs texturés ont été élaborés à partir de l'état liquide dans les systèmes Nd-Ce-Cu-O et Bi-Sr-Ca-Cu-O par une technique de fusion de zone. L'influence des conditions de croissance et des compositions initiales sur la microstructure des échantillons a été étudiée par microscopie optique en lumière polarisée, microsonde électronique et diffraction des rayons X. Les propriétés supraconductrices des échantillons ont été examinées par des mesures électriques et magnétiques. Il a été observé une forte influence de la microstructure sur les propriétés supraconductrices ainsi qu'une anisotropie électrique et magnétique. Dans le cas du système Bi-Sr-Ca-Cu-O, les densités de courant critique mesurées à 77 K sont comprises entre 1 600 et 3 000 A.cm^{-2}.

  7. Molecular Environmental Science: An Assessment of Research Accomplishments, Available Synchrotron Radiation Facilities, and Needs

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G

    2004-02-05

    their reactions with environmental materials. To achieve this goal, both fundamental and targeted studies of complex environmental systems at a molecular level are needed, and examples of both types of studies are presented herein. These examples illustrate the fact that MES SR studies have led to a revolution in our understanding of the fundamental physical and chemical aspects of natural systems. The MES SR user community has continued to experience strong growth at U.S. SR laboratories, with MES researchers comprising up to 15% of the total user base. Further growth and development of the MES community is being hindered by insufficient resources, including support personnel, materials preparation facilities, and available beam time at U.S. SR laboratories. ''EnviroSync'' recommends the following actions, in cooperation with U.S. SR laboratory directors, to meet the MES community's needs.

  8. Molecular Environmental Science: An Assessment of Research Accomplishments, Available Synchrotron Radiation Facilities, and Needs

    International Nuclear Information System (INIS)

    Brown, G

    2004-01-01

    environmental materials. To achieve this goal, both fundamental and targeted studies of complex environmental systems at a molecular level are needed, and examples of both types of studies are presented herein. These examples illustrate the fact that MES SR studies have led to a revolution in our understanding of the fundamental physical and chemical aspects of natural systems. The MES SR user community has continued to experience strong growth at U.S. SR laboratories, with MES researchers comprising up to 15% of the total user base. Further growth and development of the MES community is being hindered by insufficient resources, including support personnel, materials preparation facilities, and available beam time at U.S. SR laboratories. ''EnviroSync'' recommends the following actions, in cooperation with U.S. SR laboratory directors, to meet the MES community's needs

  9. Molecular environmental science : an assessment of research accomplishments, available synchrotron radiation facilities, and needs.

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G. E., Jr.; Sutton, S. R.; Bargar, J. R.; Shuh, D. K.; Fenter, P. A.; Kemner, K. M.

    2004-10-20

    their reactions with environmental materials. To achieve this goal, both fundamental and targeted studies of complex environmental systems at a molecular level are needed, and examples of both types of studies are presented herein. These examples illustrate the fact that MES SR studies have led to a revolution in our understanding of the fundamental physical and chemical aspects of natural systems. The MES SR user community has continued to experience strong growth at U.S. SR laboratories, with MES researchers comprising up to 15% of the total user base. Further growth and development of the MES community is being hindered by insufficient resources, including support personnel, materials preparation facilities, and available beam time at U.S. SR laboratories. EnviroSync* recommends the following actions, in cooperation with U.S. SR laboratory directors, to meet the MES community's needs.

  10. BENCHMARKING AND CONFIGURATION OF OPENSOURCE MANUFACTURING EXECUTION SYSTEM (MES APPLICATION

    Directory of Open Access Journals (Sweden)

    Ganesha Nur Laksmana

    2013-05-01

    Full Text Available Information now is an important element to every growing industry in the world. Inorder to keep up with other competitors, endless improvements in optimizing overall efficiency areneeded. There still exist barriers that separate departments in PT. XYZ and cause limitation to theinformation sharing in the system. Open-Source Manufacturing Execution System (MES presentsas an IT-based application that offers wide variety of customization to eliminate stovepipes bysharing information between departments. Benchmarking is used to choose the best Open-SourceMES Application; and Dynamic System Development Method (DSDM is adopted as this workguideline. As a result, recommendations of the chosen Open-Source MES Application arerepresented.Keywords: Manufacturing Execution System (MES; Open Source; Dynamic SystemDevelopment Method (DSDM; Benchmarking; Configuration

  11. Maxdose-SR and popdose-SR routine release atmospheric dose models used at SRS

    Energy Technology Data Exchange (ETDEWEB)

    Jannik, G. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Trimor, P. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-07-28

    MAXDOSE-SR and POPDOSE-SR are used to calculate dose to the offsite Reference Person and to the surrounding Savannah River Site (SRS) population respectively following routine releases of atmospheric radioactivity. These models are currently accessed through the Dose Model Version 2014 graphical user interface (GUI). MAXDOSE-SR and POPDOSE-SR are personal computer (PC) versions of MAXIGASP and POPGASP, which both resided on the SRS IBM Mainframe. These two codes follow U.S. Nuclear Regulatory Commission (USNRC) Regulatory Guides 1.109 and 1.111 (1977a, 1977b). The basis for MAXDOSE-SR and POPDOSE-SR are USNRC developed codes XOQDOQ (Sagendorf et. al 1982) and GASPAR (Eckerman et. al 1980). Both of these codes have previously been verified for use at SRS (Simpkins 1999 and 2000). The revisions incorporated into MAXDOSE-SR and POPDOSE-SR Version 2014 (hereafter referred to as MAXDOSE-SR and POPDOSE-SR unless otherwise noted) were made per Computer Program Modification Tracker (CPMT) number Q-CMT-A-00016 (Appendix D). Version 2014 was verified for use at SRS in Dixon (2014).

  12. Processes of Quantum Associative Memory (QuAM) Through New Maximally Entangled States (Singh-Rajput MES)

    Science.gov (United States)

    Singh, Manu Pratap; Rajput, B. S.

    2016-07-01

    Using Singh-Rajput MES as memory states in the evolutionary process of pattern storage and the non-evolutionary process of pattern recall (the two fundamental constituents of QuAM), the suitability and superiority of these MES over Bell's MES have been demonstrated in both these processes. It has been shown that, under the operations of all the possible memorization operators for a two-qubit system, the first two states of Singh-Rajput MES are useful for storing the pattern |11> and the last two of these MES are useful in storing the pattern |10> while Bell's MES are not much suitable as memory states in a valid memorization process. The recall operations have also been conducted by separately choosing Singh-Rajput MES and Bell's MES as memory states for possible various queries and it has been shown that in each case the choices of Singh-Rajput MES as valid memory states are much more suitable than those of Bell's MES.

  13. Identification of the Drosophila Mes4 gene as a novel target of the transcription factor DREF

    Energy Technology Data Exchange (ETDEWEB)

    Suyari, Osamu; Ida, Hiroyuki [Department of Applied Biology, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan); Insect Biomedical Research Center, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan); Yoshioka, Yasuhide; Kato, Yasuko; Hashimoto, Reina [Department of Applied Biology, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan); Insect Biomedical Research Center, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan); Venture Laboratory, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan); Yamaguchi, Masamitsu, E-mail: myamaguc@kit.ac.jp [Department of Applied Biology, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan); Insect Biomedical Research Center, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan)

    2009-05-01

    The Mes4 gene has been identified as one of the maternal Dorsal target genes in Drosophila. In the present study, we found a DNA replication-related element (DRE, 5'-TATCGATA) in the Mes4 promoter recognized by the DRE-binding factor (DREF). Luciferase transient expression assays in S2 cells using Mes4 promoter-luciferase fusion plasmids revealed that the DRE sequence is essential for Mes4 promoter activity. Requirement of DRE for Mes4 promoter activity was further confirmed by anti-{beta}-galactosidase antibody-staining of various tissues from transgenic flies carrying Mes4 promoter-lacZ fusion genes. Furthermore, wild type Mes4 promoter activity was decreased by 40% in DREF-depleted S2 cells. These results indicate that DREF positively regulates Mes4 gene expression. Band mobility shift analyses using Kc cell nuclear extracts further indicated that the DRE sequence in the Mes4 promoter is especially important for binding to DREF. Moreover, specific binding of DREF to the involved genomic region could be demonstrated by chromatin immunoprecipitation assays using anti-DREF antibodies. These results, taken together, indicate that the DRE/DREF system activates transcription of the Mes4 gene. In addition, knockdown of the Mes4 gene in wing imaginal discs using the GAL4-UAS system caused an atrophied wing phenotype, suggesting that Mes4 is required for wing morphogenesis.

  14. Identification of the Drosophila Mes4 gene as a novel target of the transcription factor DREF

    International Nuclear Information System (INIS)

    Suyari, Osamu; Ida, Hiroyuki; Yoshioka, Yasuhide; Kato, Yasuko; Hashimoto, Reina; Yamaguchi, Masamitsu

    2009-01-01

    The Mes4 gene has been identified as one of the maternal Dorsal target genes in Drosophila. In the present study, we found a DNA replication-related element (DRE, 5'-TATCGATA) in the Mes4 promoter recognized by the DRE-binding factor (DREF). Luciferase transient expression assays in S2 cells using Mes4 promoter-luciferase fusion plasmids revealed that the DRE sequence is essential for Mes4 promoter activity. Requirement of DRE for Mes4 promoter activity was further confirmed by anti-β-galactosidase antibody-staining of various tissues from transgenic flies carrying Mes4 promoter-lacZ fusion genes. Furthermore, wild type Mes4 promoter activity was decreased by 40% in DREF-depleted S2 cells. These results indicate that DREF positively regulates Mes4 gene expression. Band mobility shift analyses using Kc cell nuclear extracts further indicated that the DRE sequence in the Mes4 promoter is especially important for binding to DREF. Moreover, specific binding of DREF to the involved genomic region could be demonstrated by chromatin immunoprecipitation assays using anti-DREF antibodies. These results, taken together, indicate that the DRE/DREF system activates transcription of the Mes4 gene. In addition, knockdown of the Mes4 gene in wing imaginal discs using the GAL4-UAS system caused an atrophied wing phenotype, suggesting that Mes4 is required for wing morphogenesis.

  15. mes

    OpenAIRE

    Manniez, Yves

    2013-01-01

    Date de l'opération : 1994 (SU) Inventeur(s) : Manniez Yves (AFAN) Plan général des opérations extra muros de Nîmes (Fig. n°2 : Plan général des principales opérations rurales (1991-1998)). En préalable à la construction d’un bâtiment, une expertise archéologique a été réalisée dans la parcelle HB-462 jouxtant au sud la route de Beaucaire et à l’ouest un cours d’eau temporaire aujourd’hui couvert (rue Bergson) (Monteil, Martial. 1999. ) (Fig. n°1 : Plan de localisation des opérations des 74-...

  16. mes

    OpenAIRE

    Hervé, Marie-Laure

    2013-01-01

    Date de l'opération : 1995 (SD) Inventeur(s) : Hervé Marie-Laure (AFAN) Plan général des opérations extra muros de Nîmes (Fig. n°3 : Plan général des principales opérations rurales (1991-1998)). En préalable à l’établissement d’une construction venant remplacer une station-service, une expertise archéologique a été réalisée dans la parcelle CX-499, CX-500 qui aurait livré en 1931 les restes d’un monument funéraire (Espérandieu, Emile. 1932. ) [ (Fig. n°1 : Plan de localisation des opérations...

  17. Systèmes multi-échelles, Modélisation et simulation

    Science.gov (United States)

    Le Bris, Claude

    Systèmes multi-échelles est une introduction à la problématique des systèmes multi-échelles du point de vue du mathématicien appliqué. Il se compose d'une mosaique d'exemples dont le seul lien est d'appartenir à la très grande famille des problèmes issus de la physique au sens large qui présentent pour leur modélisation et leur simulation cette difficulté essentielle de comporter en leur sein des échelles de temps oud'espace très différentes.

  18. La dévotion aux âmes du purgatoire à Rio de Janeiro

    OpenAIRE

    Augras, Monique

    2009-01-01

    La dévotion aux âmes du purgatoire est particulièrement vive à Rio de Janeiro. A peu près tolérée par l’Église catholique, elle réunit, chaque lundi, un nombre assez considérable de personnes qui viennent prier, allumer un cierge et déposer diverses offrandes afin de se ménager l’appui des « âmes » pour résoudre les problèmes les plus pressants. A la différence des saints du paradis, dont les vertus les éloignent peut-être du commun des gens, la dévotion aux âmes semble s’appuyer sur une nett...

  19. Gouvernance des systèmes alimentaires urbains pour la prévention ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... contre ces systèmes alimentaires en évolution et l'augmentation connexe des maladies ... les systèmes d'information et d'enregistrement des faits d'état civil dans les pays en ... GrowInclusive : la plateforme tant attendue est en construction.

  20. Applications of Singh-Rajput Mes in Recall Operations of Quantum Associative Memory for a Two- Qubit System

    Science.gov (United States)

    Singh, Manu Pratap; Rajput, B. S.

    2016-03-01

    Recall operations of quantum associative memory (QuAM) have been conducted separately through evolutionary as well as non-evolutionary processes in terms of unitary and non- unitary operators respectively by separately choosing our recently derived maximally entangled states (Singh-Rajput MES) and Bell's MES as memory states for various queries and it has been shown that in each case the choices of Singh-Rajput MES as valid memory states are much more suitable than those of Bell's MES. it has been demonstrated that in both the types of recall processes the first and the fourth states of Singh-Rajput MES are most suitable choices as memory states for the queries `11' and `00' respectively while none of the Bell's MES is a suitable choice as valid memory state in these recall processes. It has been demonstrated that all the four states of Singh-Rajput MES are suitable choice as valid memory states for the queries `1?', `?1', `?0' and `0?' while none of the Bell's MES is suitable choice as the valid memory state for these queries also.

  1. Bistable minimum energy structures (BiMES) for binary robotics

    International Nuclear Information System (INIS)

    Follador, M; Conn, A T; Rossiter, J

    2015-01-01

    Bistable minimum energy structures (BiMES) are devices derived from the union of the concepts of dielectric elastomer minimum energy structures and bistable systems. This article presents this novel approach to active, elastic and bistable structures. BiMES are based on dielectric elastomer actuators (DEAs), which act as antagonists and provide the actuation for switching between the two equilibrium positions. A central elastic beam is the backbone of the structure and is buckled into the minimum energy configurations by the action of the two DEAs. The theory and the model of the device are presented, and also its fabrication process. BiMES are considered as fundamental units for more complex structures, which are presented and fabricated as proof of concept. Two different ways of combining the multiple units are proposed: a parallel configuration, to make a simple gripper, and a serial configuration, to generate a binary device. The possibility of using the bistable system as a continuous bender actuator, by modulating the actuation voltage of the two DEAs, was also investigated. (paper)

  2. MES Development Framework: Concepts, Ideas, Implementation

    DEFF Research Database (Denmark)

    Caponetti, Fabio; Papaleo, Massimiliano

    MES development remains primarily a labour-intensive effort, thus subject to human limitations. ISA-95 defines a modeling road map, however, engineering techniques have advanced only moderately. Inevitably, the development process introduces errors beginning in requirements formulation, continuing...... performance, reduced dimensions, easier maintenance and coding are the key results of the project....

  3. Initiatives canadiennes d'avant-garde en matière de systèmes de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Initiatives canadiennes d'avant-garde en matière de systèmes de santé équitables et d'amélioration de la santé des mères et des enfants ... renforcement des systèmes de santé : d'une part, le recrutement des travailleurs de la santé, le maintien de cet effectif et, d'autre part, le rôle des systèmes d'information sur la santé.

  4. Systèmes d'information sanitaire ou santé sexuelle et reproductive ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    23 mai 2017 ... Systèmes d'information sanitaire ou santé sexuelle et reproductive des adolescents en Afrique de l'Ouest. Appel. Propositions. Programme(s) ... Sujet(s). Systèmes de santé, ADOLESCENTS, SANTÉ REPRODUCTIVE, DROITS EN MATIERE DE PROCREATION. Durée. 36 à 48 mois. Financée par. CRDI ...

  5. OpenSR: An Open-Source Stimulus-Response Testing Framework

    Directory of Open Access Journals (Sweden)

    Carolyn C. Matheus

    2015-01-01

    Full Text Available Stimulus–response (S–R tests provide a unique way to acquire information about human perception by capturing automatic responses to stimuli and attentional processes. This paper presents OpenSR, a user-centered S–R testing framework providing a graphical user interface that can be used by researchers to customize, administer, and manage one type of S–R test, the implicit association test. OpenSR provides an extensible open-source Web-based framework that is platform independent and can be implemented on most computers using any operating system. In addition, it provides capabilities for automatically generating and assigning participant identifications, assigning participants to different condition groups, tracking responses, and facilitating collecting and exporting of data. The Web technologies and languages used in creating the OpenSR framework are discussed, namely, HTML5, CSS3, JavaScript, jQuery, Twitter Bootstrap, Python, and Django. OpenSR is available for free download.

  6. A Comparative Study of the Eco toxicity of Palm-Based Methyl Ester Sulphonates (MES) to Tilapia and Daphnia magna

    International Nuclear Information System (INIS)

    Razmah, G.; Afida, I.S.; Zulina, A.M.; Noorazah, Z.; Hazimah, A.H.

    2016-01-01

    Methyl ester sulphonates (MES) is a surfactant derived from plant resources, suitable as active ingredient in detergents. MES possesses good surface-active properties, good detergency and tolerant to water hardness. In this study, the eco toxicity of MES was evaluated through the 48 hr Daphnia magna immobilisation test and the 96 hr fish acute toxicity test with Tilapia. MES samples with different alkyl chain lengths (C14, C16 and C16:18) produced by the Malaysian Palm Oil Board (MPOB) and commercial MES (C16:18) were tested. Results from all tests indicated that Daphnia was more sensitive to toxic effects from MES than was Tilapia. There is also significant difference in eco toxicity responses for palm-based MES of various chain lengths regardless of the species tested. The eco toxicity increased as the hydrophobicity of the MES increased due to increase of alkyl chain length. However, less than 30 % of MES is used in detergent products and will not pose environmental effects on aquatic organisms. MES is therefore suitable for environmental compatible cleaning products in view of its eco toxicity that is on par to the widely used anionic surfactants, such as linear alkylbenzene sulphonate (LAS). The use of MES in cleaning products may help the industry to fulfil its social responsibility to a cleaner and better environment. (author)

  7. PRIA ja MES teevad koostööd maaelu edendamiseks / Heli Raamets

    Index Scriptorium Estoniae

    Raamets, Heli, 1975-

    2004-01-01

    Ilmunud ka: Nädaline : Maakonna Talu Leht, 16. okt. 2004, lk. 1. Põllumajanduse Registrite ja Informatsiooni Amet (PRIA) ning Maaelu Edendamise Sihtasutus (MES) sõlmisid kokkuleppe, mille alusel külaelu arendajatel, kellele PRIA määras või määrab investeeringutoetuse, on võimalik saada omaosaluse rahastamiseks MES-ist laenu või tagatist pangalaenu jaoks

  8. Communication Standards Suitable for MES Systems Designed for SMES

    Directory of Open Access Journals (Sweden)

    Ondřej WINKLER

    2009-06-01

    Full Text Available A MES (Manufacturing Execution System is a system that large companies use to measure or control critical production activities. Individual parts of this system can be used as a model for development of tools suitable for small and medium enterprises (SMEs. It can demonstrate how manufacturing systems works and which communication standards are usable. The communication standards enable data acquisition, data processing, storing and their conversion for any production report. Furthermore, interfaces for web clients allow displaying the raw or transformed data as a text or a graphic chart. The development of tools for an access to the data retrieved from MES software is described in this paper.

  9. Analyste de systèmes intermédiaire (h/f) | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'analyste de systèmes intermédiaire travaille sous la supervision du ... à la mise en œuvre et à la maintenance d'un large éventail de systèmes tout en assurant ... directement les consultants externes sous contrat afin de faciliter la transition ...

  10. The Use of BPMN for Modelling The MES Level in Information and Control Systems

    Directory of Open Access Journals (Sweden)

    Peter Michalik

    2013-07-01

    Full Text Available This paper describes how to use the process map to model the MES level of information and control systems. In the practical application, the BPMN standard was used for the design of the function of the management maintenance, which, according MES organization, is one of the 11 basic MES functions. The application was implemented on the flexible production line, located in the laboratory at the Department of Cybernetics and Artificial Intelligence. In this article, there is only one BPMN model of  a MES function from the set of modelled functions in our laboratory. These functions were also modelled by the UML Activity Diagram. Although the UML model is not included in this article, there is a comparison of these approaches based on selected criteria and our experiences with modelling in the laboratory at the university.

  11. Schéma directeur des Systèmes d'information 2012-2016

    OpenAIRE

    Institut National de Recherche Agronomique UAR 0776 Administration du siège

    2012-01-01

    Le schéma directeur des systèmes d’information de l’inra est le premier Schéma directeur dont l’institut se dote dans le champ des systèmes D’information. Il couvre la période 2012‐2016 du contrat d’objectifs Et s’inscrit dans les perspectives scientifiques dressées par le document D’orientation 2010‐2020

  12. Soutien au programme de recherche du GCRAI sur les systèmes d ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Plus de 700 millions de personnes dépendent de systèmes d'aquaculture pour gagner leur vie. Ces systèmes agricoles diversifiés combinent culture, élevage, aquaculture, pêche et collecte de ressources naturelles comme les fruits, les graines, le bois et la faune. Toutefois, de nombreuses contraintes empêchent les petits ...

  13. A Proposal for Production Data Collection on a Hybrid Production Line in Cooperation with MES

    Science.gov (United States)

    Znamenák, Jaroslav; Križanová, Gabriela; Iringová, Miriam; Važan, Pavel

    2016-12-01

    Due to the increasing competitive environment in the manufacturing sector, many industries have the need for a computer integrated engineering management system. The Manufacturing Execution System (MES) is a computer system designed for product manufacturing with high quality, low cost and minimum lead time. MES is a type of middleware providing the required information for the optimization of production from launching of a product order to its completion. There are many studies dealing with the advantages of the use of MES, but little research was conducted on how to implement MES effectively. A solution to this issue are KPIs. KPIs are important to many strategic philosophies or practices for improving the production process. This paper describes a proposal for analyzing manufacturing system parameters with the use of KPIs.

  14. A Proposal for Production Data Collection on a Hybrid Production Line in Cooperation with MES

    Directory of Open Access Journals (Sweden)

    Znamenák Jaroslav

    2016-12-01

    Full Text Available Due to the increasing competitive environment in the manufacturing sector, many industries have the need for a computer integrated engineering management system. The Manufacturing Execution System (MES is a computer system designed for product manufacturing with high quality, low cost and minimum lead time. MES is a type of middleware providing the required information for the optimization of production from launching of a product order to its completion. There are many studies dealing with the advantages of the use of MES, but little research was conducted on how to implement MES effectively. A solution to this issue are KPIs. KPIs are important to many strategic philosophies or practices for improving the production process. This paper describes a proposal for analyzing manufacturing system parameters with the use of KPIs.

  15. PyMES INNOVADORAS. Cambio de Estrategias e Instrumentos

    Directory of Open Access Journals (Sweden)

    Juan Gonzalo Castellanos

    2003-07-01

    Full Text Available ¿Cómo hacer que las PyMES aumenten el valor de sus productos y servicios? ¿Cómo incorporar valor-conocimiento a la totalidad de la organización? Se intenta en este escrito introducir algunos conceptos útiles para comprender mejor la compleja realidad de los pequeños y medianos negocios en el mercado de hoy. En este artículo se trabajan conceptos relativos a la innovación como actividad primordial e integradora en el quehacer de una empresa competitiva y se revisan los resultados de diversos estudios sobre innovación y PyMES en el mundo desarrollado y en desarrollo, incluyendo los resultados del análisis de los casos elaborados dentro del ejercicio que promueve la Escuela de Administración de Negocios EAN en la línea de investigación sobre pequeñas y medianas empresas.

  16. Zeolite/magnetite composites as catalysts on the Synthesis of Methyl Esters (MES) from cooking oil

    Science.gov (United States)

    Sriatun; Darmawan, Adi; Sriyanti; Cahyani, Wuri; Widyandari, Hendri

    2018-05-01

    The using of zeolite/magnetite composite as a catalyst for the synthesis of methyl esters (MES) of cooking oil has been performed. In this study the natural magnetite was extracted from the iron sand of Semarang marina beach and milled by high energy Milling (HEM) with ball: magnetite ratio: 1:1. The composites prepared from natural zeolite and natural magnetite with zeolite: magnetite ratio 1:1; 2:1; 3:1 and 4:1. Preparation of methyl ester was catalyzed by composite of zeolite/magnetite through transeserification reaction, it was studied on variation of catalyst concentration (w/v) 1%, 3%, 5% and 10% to feed volume. The reaction product are mixture of methyl Oleic (MES), methyl Palmitic (MES) and methyl Stearic (MES). Character product of this research include density, viscosity, acid number and iodine number has fulfilled to SNI standard 7182: 2015.

  17. Componentes empresariales en las MIPyMES colombianas

    Directory of Open Access Journals (Sweden)

    Rafael Ignacio Pérez Uribe

    2013-07-01

    Full Text Available Varios estudios en Colombia evidencian las oportunidades de mejoramiento de este tipo de empresas. En este artículo solo mencionaremos los más representativos. En ellos se muestra de manera clara y suficiente a qué tienen que enfrentarse las MIPyMES para lograr una sostenibilidad que les permita ser empresas de clase mundial.

  18. Adopción por primera vez de la NIIF para las PyMEs en PyMEs argentinas: análisis normativo y cuestiones de aplicación

    OpenAIRE

    Rondi, Gustavo R.; Casal, María del Carmen; Galante, Marcelo Javier; Gómez, Melisa

    2013-01-01

    En el desarrollo de este trabajo se abordan las situaciones y dificultades de orden práctico que pueden presentarse cuando una PyME argentina decide adoptar por primera vez la NIIF para las PyMEs. Para ello, se han analizado el tratamiento que la NIIF para las PyMEs y las normas contables argentinas contemplan para los cambios de políticas contables; las simplificaciones, exenciones especiales y requerimientos específicos que la NIIF establece en su adopción por primera vez; y las principales...

  19. Interkoneksi Stain, Bsm, Dan Mes Dalam Mengembangkan Ekonomi Islam: Studi Kasus Di Purwokerto

    OpenAIRE

    Dahlan, Ahmad

    2008-01-01

    STAIN, Bank Syariah Mandiri (BSM), and Masyarakat Ekonomi Syariah (MES, Syariah Economic Society) have important rolein the development of Islam economy in Purwokerto. This research result evidenced that these three institutions have an Islamic economydevelopment program according with vision and mission of their institution. STAIN as Islamic higher education is on curriculum design andlecture quality domain, BSM as banking financial institution on enhancing employee/manager quality, and MES ...

  20. INTERKONEKSI STAIN, BSM, DAN MES DALAM MENGEMBANGKAN EKONOMI ISLAM: STUDI KASUS DI PURWOKERTO

    OpenAIRE

    Dahlan, Ahmad

    2015-01-01

    STAIN, Bank Syariah Mandiri (BSM), and Masyarakat Ekonomi Syariah (MES, Syariah Economic Society) have important rolein the development of Islam economy in Purwokerto. This research result evidenced that these three institutions have an Islamic economydevelopment program according with vision and mission of their institution. STAIN as Islamic higher education is on curriculum design andlecture quality domain, BSM as banking financial institution on enhancing employee/manager quality, and MES ...

  1. Relativité problèmes résolus

    CERN Document Server

    Lumbroso, Hubert

    1979-01-01

    Ce recueil de problèmes de Relativité Restreinte s'adresse aux élèves des classes préparatoires aux grandes écoles d'ingénieurs (mathématiques spéciales) et aux étudiants du premier cycle universitaire scientifique (D.E.U.G.).

  2. ProMES: A method for "accepted control loops"

    NARCIS (Netherlands)

    Tuijl, van H.F.J.M.

    1997-01-01

    ProMES, a method for the measurement and feedback of performance data is related to the concepts of goal setting and feedback (Locke, 1991; Locke and Latham, 1990), and to the concept of self-control (Bandura, 1991). The result is a model for self-management: the "accepted control loop". Whether

  3. Systèmes de recommandation et Recherche d'Information

    OpenAIRE

    Candillier , Laurent; Chai , Etienne; Delpech , Estelle

    2012-01-01

    National audience; Cet article traite de l'application des technologies de recommandation aux systèmes de Recherche d'Information. Nous y détaillons un cas d'application à la recherche de lieux à travers la présentation de l'annuaire Nomao.

  4. Environmental Science Program at the Advanced Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, Susan; Shuh, David; Nico, Peter

    2005-06-01

    Synchrotron Radiation (SR)-based techniques have become an essential and fundamental research tool in Molecular Environmental Science (MES) research. MES is an emerging scientific field that has largely evolved from research interactions at the U.S. Department of Energy (U.S. DOE) SR laboratories in response to the pressing need for understanding fundamental molecular-level chemical and biological processes that involve the speciation, properties, and behavior of contaminants, within natural systems. The role of SR-based investigations in MES and their impact on environmental problems of importance to society has been recently documented in Molecular Environmental Science: An Assessment of Research Accomplishment, Available Synchrotron Radiation Facilities, and Needs (EnviroSync, 2003).

  5. El efecto fin de mes en los principales mercados accionarios latinoamericanos

    Directory of Open Access Journals (Sweden)

    Werner Kristjanpoller Rodríguez

    2015-01-01

    Full Text Available En los mercados accionarios es frecuente encontrar anomalías de calendario, las cuales han sido objeto de diversos estudios en estas últimas décadas, incluso demostrándose que algunas de ellas a través del tiempo han ido desapareciendo. En este contexto, este artículo analiza una de estas anomalías, el efecto fin de mes, tanto en rendimiento como en volatilidad en los mercados accionarios de seis países latinoamericanos; a saber, Brasil, México, Chile, Colombia, Perú y Argentina en el periodo 1993-2011. La importancia de este estudio radica en poder probar si el efecto de fin de mes ha ido desapareciendo o aún persiste, ya que algunos efectos calendario en mercados accionarios desarrollados se han ido disipando. Los hallazgos de esta investigación, que se realizó de acuerdo con los tres periodos diferentes definidos en la literatura para analizar el impacto fin de mes, muestran que la mayoría de los países bajo análisis obtienen rendimientos anormales positivos en los días asociados al cambio de mes y también muestran anomalías en la volatilidad. Esta investigación no solamente analiza los índices característicos de cada mercado, sino que también las acciones en particular de cada uno, dotándolo de una muestra mucho mayor y exigente al momento de concluir sobre la existencia del fenómeno. También se incluye un análisis de volumen de transacción para verificar ciertas hipótesis del fenómeno asociadas a mayor flujo de efectivo.

  6. The Novice User and CD-ROM Database Services. ERIC Digest.

    Science.gov (United States)

    Schamber, Linda

    This digest answers the following questions that beginning or novice users may have about CD-ROM (a compact disk with read-only memory) database services: (1) What is CD-ROM? (2) What databases are available? (3) Is CD-ROM difficult to use? (4) How much does CD-ROM cost? and (5) What is the future of CD-ROM? (15 references) (MES)

  7. Film Presentation: Big Bang, mes ancêtres et moi

    CERN Multimedia

    2010-01-01

    Big Bang, mes ancêtres et moi, by Franco-German TV producer ARTE (2009)   What do we know about the origins of the world today? This documentary presents a voyage into the mystery of these origins, accompanied by passionate scientists such as paleoanthropologist Pascal Picq, astrophysicist Hubert Reeves, physicist Etienne Klein and quantum gravity theorist Abhay Ashtekar. Organized around three key moments – the birth of the Universe, the appearance of life and the origins of mankind – this investigation takes us to various research areas around the world, including the large underground particle accelerator at CERN. The German version of this film, Big Bang im Labor, will be presented on 1st October. Big Bang, mes ancêtres et moi will be shown on Friday, 24 September from 13:00 to 14:00 in room 222-R-001 Language: French Big Bang im Labor will be shown on Friday, 1 October from 13:00 to 14:00 in the Main Auditorium Language : German   &nbs...

  8. BIBLIO: A Computer System Designed to Support the Near-Library User Model of Information Retrieval.

    Science.gov (United States)

    Belew, Richard K.; Holland, Maurita Peterson

    1988-01-01

    Description of the development of the Information Exchange Facility, a prototype microcomputer-based personal bibliographic facility, covers software selection, user selection, overview of the system, and evaluation. The plan for an integrated system, BIBLIO, and the future role of libraries are discussed. (eight references) (MES)

  9. Evaluación de un proyecto de éxito para PyMEs costarricenses

    OpenAIRE

    Quesada Pineda, Henry

    2013-01-01

    Los investigadores Henry Quesada y Marcela Meneses, de la Escuela de Ingeniería en Producción Industrial del Instituto Tecnológico de Costa Rica (TEC), realizaron una investigación durante el periodo 2007 a 2008 con la intención de identificar si existe un patrón en un modelo de negocios para pequeñas y medianas empresas (PyMEs) que les haya permitido ser competitivas a escala nacional o internacional. El aporte económico de las PyMEs en Costa Rica ha sido documentado en muchas investigacione...

  10. Archivage électronique : spécifications relatives à la conception et à l'exploitation de systèmes informatiques en vue d'assurer la conservation et l'intégrité des documents stockés dans ces systèmes

    CERN Document Server

    Association Française de Normalisation. Paris

    2007-01-01

    Archivage électronique : spécifications relatives à la conception et à l'exploitation de systèmes informatiques en vue d'assurer la conservation et l'intégrité des documents stockés dans ces systèmes

  11. PyMES COLOMBIANAS Y LA GESTIÓN DEL CONOCIMIENTO

    Directory of Open Access Journals (Sweden)

    Andrea Carolina Bustos Claro

    2003-07-01

    Full Text Available En los últimos años, la adaptación de modelos e-business se ha convertido en un elemento de vital importancia para las organizaciones, hasta el punto de creer que ésta es la mejor forma de crear una ventaja competitiva en el mercado global. Sin embargo, es necesario tener presente que la existencia de la tecnología por sí sola, no asegura el éxito. Se requiere además del cambio de algunos paradigmas organizacionales: lacultura, los niveles jerárquicos y el manejo que se le da a la información y a la comunicación. Gracias a los resultados obtenidos en el proyecto “Indicadores Pragmáticos de Gestión del Conocimiento aplicado a páginas Web de PyMES colombianas”, adelantado por el Centro de Investigaciones de la EAN, se ha logrado un acercamiento a la situación actual de las páginas Web de las PyMES y su desempeño en la red.

  12. The Moment of Learning: Quantitative Analysis of Exemplar Gameplay Supports CyGaMEs Approach to Embedded Assessment

    Science.gov (United States)

    Reese, Debbie Denise; Tabachnick, Barbara G.

    2010-01-01

    In this paper, the authors summarize a quantitative analysis demonstrating that the CyGaMEs toolset for embedded assessment of learning within instructional games measures growth in conceptual knowledge by quantifying player behavior. CyGaMEs stands for Cyberlearning through GaME-based, Metaphor Enhanced Learning Objects. Some scientists of…

  13. Droits des femmes et accès à l'eau et aux systèmes d ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Partout sur la planète, les citadines pauvres doivent composer chaque jour avec les problèmes liés à l'absence de systèmes d'assainissement sûrs, abordables, accessibles et appropriées. L'ONG Women in Cities International (WICI) tente de trouver des moyens de remédier à cette situation en Inde. Cette subvention lui ...

  14. Les grands problèmes mathématiques ils orientent l'avenir des maths

    CERN Document Server

    2012-01-01

    Les mathématiques ont leurs sept merveilles ! Il s’agit des sept problèmes du millénaire, mis à prix à un million de dollars chacun par l’Institut Clay de mathématiques en 2000. Mais l’intelligence des mathématiciens est aussi mise à l’épreuve par bien d’autres problèmes, tels ceux de Hilbert. Découvrez dans ce numéro comment ces énigmes orientent l’avenir de la discipline ouvrant la voie à de nouvelles connaissances fondamentales.

  15. VizieR Online Data Catalog: HerMES Large Mode Survey catalogue (Asboth+, 2016)

    Science.gov (United States)

    Asboth, V.; Conley, A.; Sayers, J.; Bethermin, M.; Chapman, S. C.; Clements, D. L.; Cooray, A.; Dannerbauer, H.; Farrah, D.; Glenn, J.; Golwala, S. R.; Halpern, M.; Ibar, E.; Ivison, R. J.; Maloney, P. R.; Marques-Chaves, R.; Martinez-Navajas, P. I.; Oliver, S. J.; Perez-Fournon, I.; Riechers, D. A.; Rowan-Robinson, M.; Scott, D.; Siegel, S. R.; Vieira, J. D.; Viero, M.; Wang, L.; Wardlow, J.; Wheeler, J.

    2018-01-01

    The HerMES Large Mode Survey (HeLMS) consists of a large area shallow observation of an equatorial field at wavelengths of 250, 350 and 500um, obtained using the SPIRE aboard the Herschel Space Observatory. HeLMS is an extension of HerMES (Oliver et al., 2012MNRAS.424.1614O, Cat. VIII/95 and VIII/103), a 'wedding cake' type survey containing small and deep maps and larger shallower observations of different fields. HeLMS covers about 302deg2 of the sky, making it the largest area observed in the HerMES. The HeLMS field spans 23h14m

  16. Gestionnaire, Systèmes financiers (h/f) | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Examiner et évaluer les répercussions des mises à niveau de l'infrastructure du CRDI .... Analyste des systèmes de gestion ... Le titulaire du poste établit le lien nécessaire entre les activités fonctionnelles financières et administratives et les ...

  17. μSR data analysis with XYfit

    International Nuclear Information System (INIS)

    Tucakov, Ivan; Brewer, Jess H.; Froese, Aaron; Lau, Angus

    2006-01-01

    The CERN MINUIT library has recently been ported to C++, facilitating the incorporation of that familiar package into a general purpose fitting application called XYfit with a graphical user interface built with Qt3. Custom theory functions can easily be added as 'plugins' to XYfit, which reads in DataTables in XML format generated by the μView spreadsheet utility (which see), thus allowing more flexible fitting of μSR spectra

  18. Systèmes de Gestion de Production et Systèmes de Contrôle de Gestion

    OpenAIRE

    Travaillé , Denis

    2009-01-01

    L'interrogation fondamentale des travaux de recherche porte sur la question de la séparabilité et de l'interaction entre système de gestion de production et système de contrôle de gestion. Le premier temps de la réflexion concerne la spécificité du contrôle de gestion en contexte de "Juste-à-Temps. Le second temps de la recherche est relatif aux systèmes d'information de production intégrés en relation avec le système de contrôle de gestion et au rôle des représentations comptables dans la qu...

  19. Systèmes d'information sur la santé

    International Development Research Centre (IDRC) Digital Library (Canada)

    personnel spécialisé — et bien souvent le leadership et la vision — pour ... Recourir aux données probantes pour réduire la mortalité maternelle au Nigeria. □ Incorporer les TIC aux systèmes de santé. □ Intégrer les collectivités à la surveillance du .... il y a lieu de mieux comprendre comment ces outils peuvent étayer la ...

  20. Pivotal Advance: Eosinophilia in the MES rat strain is caused by a loss-of-function mutation in the gene for cytochrome b(-245), alpha polypeptide (Cyba).

    Science.gov (United States)

    Mori, Masayuki; Li, Guixin; Hashimoto, Maiko; Nishio, Ayako; Tomozawa, Hiroshi; Suzuki, Nobuyoshi; Usami, Shin-ichi; Higuchi, Keiichi; Matsumoto, Kiyoshi

    2009-09-01

    MES is a rat strain that spontaneously develops severe blood eosinophilia as a hereditary trait. Herein, we report that eosinophilia in MES rats is caused by a loss-of-function mutation in the gene for cytochrome b(-245), alpha polypeptide (Cyba; also known as p22(phox)), which is an essential component of the superoxide-generating NADPH oxidase complex. The MES rat has a deletion of four nucleotides, including the 5' splice donor GpT of intron 4 of the Cyba gene. As a consequence of the deletion, a 51-nucleotide sequence of intron 4 is incorporated into the Cyba transcripts. Leukocytes from the MES strain lack both CYBA protein and NADPH oxidase activity. Nevertheless, unlike patients with chronic granulomatous disease, who suffer from infections with pathogens due to similar genetic defects in NADPH oxidase, MES rats retain normal innate immune defense against Staphylococcus aureus infection. This is due to large quantities of peritoneal eosinophils in MES rats, which phagocytose and kill the bacteria. MES rat has a balance defect due to impaired formation of otoconia in the utricles and saccules. Eosinophilia of the MES rat was normalized by introduction of a normal Cyba transgene. The mechanisms by which impairment of NADPH oxidase leads to eosinophilia in the MES rat are elusive. However, our study highlights the essential role of NADPH oxidase in homeostatic regulation of innate immunity beyond conventional microbicidial functions.

  1. Optimization of 90Sr/89Sr measurements

    Directory of Open Access Journals (Sweden)

    Legarda F.

    2012-04-01

    Full Text Available One of the key points in the double measurement method for the measurement of both, 89Sr and 90Sr, by using a proportional counter is the choice of the times at which the measurements should be done. In this paper, the formulae to calculate the 89Sr and 90Sr detection limits in conditions of radioactive equilibrium between 90Y and 90Sr are derived, and an analysis of them as a function of the time between the two measurements is done. The choice for the time of the second measurement is going to depend on the desired quality of the results to be obtained.

  2. Electronic properties and surface reactivity of SrO-terminated SrTiO3 and SrO-terminated iron-doped SrTiO3.

    Science.gov (United States)

    Staykov, Aleksandar; Tellez, Helena; Druce, John; Wu, Ji; Ishihara, Tatsumi; Kilner, John

    2018-01-01

    Surface reactivity and near-surface electronic properties of SrO-terminated SrTiO 3 and iron doped SrTiO 3 were studied with first principle methods. We have investigated the density of states (DOS) of bulk SrTiO 3 and compared it to DOS of iron-doped SrTiO 3 with different oxidation states of iron corresponding to varying oxygen vacancy content within the bulk material. The obtained bulk DOS was compared to near-surface DOS, i.e. surface states, for both SrO-terminated surface of SrTiO 3 and iron-doped SrTiO 3 . Electron density plots and electron density distribution through the entire slab models were investigated in order to understand the origin of surface electrons that can participate in oxygen reduction reaction. Furthermore, we have compared oxygen reduction reactions at elevated temperatures for SrO surfaces with and without oxygen vacancies. Our calculations demonstrate that the conduction band, which is formed mainly by the d-states of Ti, and Fe-induced states within the band gap of SrTiO 3 , are accessible only on TiO 2 terminated SrTiO 3 surface while the SrO-terminated surface introduces a tunneling barrier for the electrons populating the conductance band. First principle molecular dynamics demonstrated that at elevated temperatures the surface oxygen vacancies are essential for the oxygen reduction reaction.

  3. Actividades predominantes a nivel nacional, regional y local de las PyMEs industriales argentinas

    Directory of Open Access Journals (Sweden)

    Roark, Geraldina Yesica

    2013-06-01

    Full Text Available La creciente importancia e interés que han ido adquiriendo las Pequeñas y Medianas empresas (PyMEs en la actividad económica del país, ha originado la realización de diversos estudios, tanto de instituciones públicas como privadas, que a través de encuestas y registros han caracterizado diferentes temáticas para este tipo de empresas.En este contexto, el Departamento de Ingeniería Industrial de la Facultad de Ingeniería, perteneciente a la Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA, ubicado en la ciudad de Olavarría, se encuentra actualmente desarrollando un proyecto de investigación denominado "Cadena de valor e impacto de las actividades clave en la conducta competitiva de las PyMEs" con el objeto de evaluar sus cadenas de valor y generar propuestas de mejora que impacten positivamente en su competitividad y sustentabilidad en el sector al que pertenecen. Consecuentemente, la relevancia del presente estudio se focaliza en determinar las actividades predominantes de las PyMEs argentinas, a nivel nacional, regional y local, de forma tal de fundamentar la elección de la población objeto de estudio del citado proyecto.

  4. Problèmes linguistiques dans le système multilingues Linguistic Problems in Multilingual Systems

    Directory of Open Access Journals (Sweden)

    Moureau M.

    2006-11-01

    Full Text Available La communauté scientifique est internationale. L'industrie du pétrole est internationale. Des problèmes de communication, de langage, de langue y sont rencontrés chaque jour. C'est pourquoi, bien que tranchant assez vigoureusement sur les sujets habituels de la Revue de l'Institut Français du Pétrole, l'article de Magdeleine Moureau et Gerald Brace sur des problèmes de linguistique ne nous a pas paru trop étranger aux préoccupations de nos lecteurs pour leur être présenté. Cet article a pour but de traiter d'abord des impossibilités théoriques de la traduction, d'évoquer ensuite les modalités pratiques de sa réalisation quotidienne et de les appliquer à l'étude des problèmes inhérents à l'élaboration d'un langage documentaire multilinguisme. The aim of this paper is to discuss the theoretical impossibilities of translation, and then to describe the practical ways of actually translating, and to apply these ways to the task of studying problems inherent in elaborating a multilingual documentary language.

  5. Protection of MES23.5 dopaminergic cells by obestatin is mediated by proliferative rather than anti-apoptotic action.

    Science.gov (United States)

    Shen, Xiao-Li; Jia, Feng-Ju; Song, Ning; Xie, Jun-Xia; Jiang, Hong

    2014-02-01

    Obestatin is an endogenous peptide sharing a precursor with ghrelin. This study aims to investigate whether and how obestatin protects MES23.5 dopaminergic cells against 1-methyl-4-phenylpyridinium (MPP(+))-induced neurotoxicity. MES23.5 cells were pretreated with obestatin (10(-13)-10(-6) mol/L) for 20 min prior to incubation with 200 μmol/L MPP(+) for 12 or 24 h, or treated with obestatin alone (10(-13) to 10(-6) mol/L) for 0, 6, 12, and 24 h. The methyl thiazolyl tetrazolium (MTT) assay was used to measure cell viability. Flow cytometry was used to measure the caspase-3 activity and the mitochondrial transmembrane potential. Proliferating cell nuclear antigen (PCNA) protein levels were determined by Western blotting. Obestatin (10(-13) to 10(-7) mol/L) pretreatment blocked or even reversed the MPP(+)-induced reduction of viability in MES23.5 cells, but had no effect on MPP(+)-induced mitochondrial transmembrane potential collapse and caspase-3 activation. When applied alone, obestatin increased viability. Elevated PCNA levels occurred with 10(-7), 10(-9), 10(-11) and 10(-13) mol/L obestatin treatment for 12 h. The results suggest that the protective effects of obestatin against MPP(+) in MES23.5 cells are due to its proliferation-promoting rather than anti-apoptotic effects.

  6. CDMA à séquence directe appliqué aux systèmes de communications optiques

    OpenAIRE

    Lourdiane , Mounia

    2005-01-01

    Depuis quelques années, le besoin de systèmes de communications plus rapides et plus sures se fait sentir. Le partage entre utilisateurs de la très grande bande passante des fibres optiques nécessite des techniques d'accès adaptées. Afin de répondre à ces besoins, un certain nombre de techniques de multiplexage, dont le CDMA, ont été développées. Cette technique d'accès multiple est déjà largement utilisée dans les systèmes de communications radio-mobiles, que ce soit dans les normes américai...

  7. Consolidation des systèmes d'approvisionnement en Amérique ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les technologies de l'information et de la communication (TIC) jouent un rôle clé dans la modernisation des systèmes d'administration publique, en général, ... Reporte final : VII Conferencia Anual sobre Compras Gubernamentales de las Américas, 18 al 20 de Octubre de 2011, Santo Domingo, República Dominicana.

  8. Le renforcement des systèmes de santé | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    4 avr. 2013 ... Avec le soutien du CRDI, Walter Flores et une coalition dirigée par le Centro de Estudios para la Equidad y Gobernanza en los Sistemas de Salud ... Les briques et les clics sont importants; il est essentiel de disposer d'infrastructures convenables et de systèmes efficaces de gestion de l'information.

  9. Analyste de systèmes principal (h/f) | CRDI - Centre de recherches ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    L'analyste de systèmes principal travaille sous la supervision du ... une analyse fonctionnelle élémentaire des exigences en parlant de la portée et de la raison ... et l'infrastructure en matière de TI tout en se mettant à la place des techniciens, ...

  10. Guide du calcul en mécanique valider le comportement des systèmes techniques

    CERN Document Server

    Spenlé, Daniel

    2012-01-01

    Ce guide couvre l’essentiel des programmes de la Première STI2D aux sections de BTS pour les compétences liées à la mécanique. Pour prendre en compte les nouveautés pédagogiques, cette nouvelle édition évolue vers des systèmes « grand public » (robotique humanoïde, cycle trainer, power-ball…) ou des systèmes liés au développement durable(éolienne, scooter électrique…). Points forts - Un guide qui tient compte des orientations du nouveau programme de STI2D : - systèmes vibratoires ; - accéléromètres, effet gyroscopique ; - développement de l’énergétique. - Les disciplines Génie mécanique/Génie électrique sont décloisonnées: - introduction de dispositifs pluri-techniques ; - présentation d’interfaces liant la partie opérative à la partie commande ; - introduction de la conversion de l’énergie électrique en énergie mécanique et réciproquement, étude comportementale, point de fonctionnement, définition des grandeurs associées. - Le caractère expérimental, ...

  11. La co-conception en partenariat de systèmes agricoles innovants

    Directory of Open Access Journals (Sweden)

    Vall Eric

    2016-01-01

    Full Text Available La co-conception de systèmes agricoles innovants est une piste prometteuse pour répondre au défi de l’innovation, notamment pour les exploitations agricoles familiales africaines confrontées à de multiples changements. Mais il faut penser à la place et aux rôles tenus par de multiples acteurs (agriculteurs, conseillers, chercheurs pour produire les changements souhaités par toutes les parties, et donc réfléchir à la question du partenariat dans le processus. Cet article présente la démarche de conception en partenariat de systèmes agricoles innovants (CPSAI élaborée entre 2005 et 2015 dans l’ouest du Burkina Faso, notamment sur la gestion de la fumure organique des cultures. La CPSAI s’appuie sur un dispositif partenarial formalisé et sur une démarche progressive en trois phases itératives : (1 exploration et formalisation du partenariat, (2 conceptions et test des options de changement, (3 bilan et désengagement. Les résultats obtenus montrent que l’innovation est plus efficace et durable quand elle est le produit d’un travail partenarial.

  12. Un modelo asociativo con base tecnológica para la competitividad de PyMes: caso floricultor colombiano

    OpenAIRE

    Giraldo, Olga Lucia; Herrera, Andrea

    2004-01-01

    La globalización ha abierto los mercados haciendo que la tecnología desempeñe un papel clave en la búsqueda y logro de competitividad. Este estudio, basado en el enfoque de cluster, primero analiza la competitividad a la luz del diamante de Porter, de las PyMes colombianas centrándose en el sector floricultor; segundo estudia las áreas donde las tecnologías de información tendrían mayor impacto; y tercero propone soluciones asociativas, basadas en el modelo de ASP, para lograr que las PyMes t...

  13. Modèle conceptuel commun pour la supervision des systèmes de sûreté du CERN

    CERN Document Server

    Hammouti, L

    2000-01-01

    La supervision des systèmes de sûreté des accélérateurs et des zones expérimentales du CERN est gérée spécifiquement d'une machine à l'autre. Chaque programme a été conçu et réalisé au moyen de la technologie de l'époque et sans suivre un modèle conceptuel commun. La situation actuelle risque de poser des problèmes importants pour l'avenir. En effet la disparité des systèmes de supervision et la nécessité de les faire évoluer ou de les renouveler alourdissent sensiblement la charge de travail ainsi que le coût de la maintenance. D'autre part, il est difficile, voire impossible, de les faire communiquer entre eux, or cela constitue une des requêtes principales de l'opération pour une meilleure coordination de l'exploitation. Le but de ce document consiste à présenter les bases d'un modèle conceptuel unique, en cours d'élaboration dans le cadre du LHC, afin de répondre aux problèmes et aux requêtes posés. Ce modèle servira de référence pour le renouvellement et l'évolution ...

  14. Mot du Directeur régional Pleins feux surla recherche des systèmes ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Gloria Lihemo

    Afrique sub-saharienne. Nous y parlons du travail que fait le. CRDI pour appuyer la recherche des systèmes sanitaires qui prend en compte une approche holistique, interdisciplinaire pour une meilleure santé. Le CRDI reconnaît ...

  15. mes – 113 route de Beaucaire

    OpenAIRE

    Bel, Valérie

    2013-01-01

    Date de l'opération : 1998 (SD) Inventeur(s) : Bel Valérie (AFAN) Plan général des opérations extra muros de Nîmes  (Fig. n°3 : Plan général des principales opérations rurales (1991-1998)). En préalable à l’établissement d’un bâtiment, un diagnostic archéologique a porté sur une parcelle de 2 115 m2 qui jouxte au sud la route de Beaucaire, à environ 1,3 km à l’est de l’enceinte antique [ (Fig. n°1 : Plan de localisation des opérations des 74-76, 81, 103, 113, route de Beaucaire sur fond cadas...

  16. Armer les villes contre la faim : Systèmes alimentaires urbains ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le XXe siècle a été le témoin d'une croissance massive des populations urbaines. ... On y explore le rôle que les structures existantes de marketing et de distribution peuvent jouer pour améliorer l'accessibilité, les systèmes de distribution alimentaire en émergence et leur apport éventuel à l'élimination de la faim dans les ...

  17. AMBER and Ecolego Intercomparisons using Calculations from SR 97

    International Nuclear Information System (INIS)

    Maul, Philip; Robinson, Peter; Avila, Rodolfo; Broed, Robert; Pereira, Antonio

    2003-08-01

    The AMBER compartmental modelling software has been used by Quintessa in undertaking Performance Assessment (PA) calculations for SKI for the last four years. In particular, it was used in helping to identify key issues in the safety case for SFR 1. SSI and the Norwegian Radiation Protection Authority (NRPA) are supporting the development of Ecolego which is based on the Matlab/Simulink general purpose modelling software and provides a user-friendly Graphical User Interface which is particularly suitable for undertaking PA calculations. At SKI/SSI expert group meetings in September 2002, Quintessa presented some radionuclide transport calculations for a deep repository for spent fuel using AMBER. Comparisons were presented with calculations undertaken by SKB in their SR 97 study. It was agreed that it would be useful to undertake some intercomparison calculations using AMBER and Ecolego based on calculation cases considered in SR 97. The reasons for undertaking such intercomparisons include: 1. to give confidence in the use of AMBER and Ecolego for whole system PA calculations for a deep repository; and 2. to provide SKI and SSI with an understanding of some of the technical issues raised by seeking to repeat the SR 97 calculations with different models and software. This report documents the intercomparison calculations that have been undertaken. The main conclusions that have been drawn are: 1. Both modelling packages could successfully reproduce SKB's SR 97 calculations for the near field, geosphere and biosphere. 2. The results of the deterministic calculations for the near field and both deterministic and probabilistic calculations for the biosphere, where AMBER and Ecolego used compartment models, were typically in agreement to within one significant figure. The identical results for the calculated equilibrium inventories in Bay sediments illustrate that the calculations by AMBER and Ecolego are essentially the same when the compartment models are identical

  18. Optical bar code recognition of methyl salicylate (MES) for environmental monitoring using fluorescence resonance energy transfer (FRET) on thin films

    Science.gov (United States)

    Smith, Clint; Tatineni, Balaji; Anderson, John; Tepper, Gary

    2006-10-01

    Fluorescence resonance energy transfer (FRET) is a process in which energy is transferred nonradiatively from one fluorophore (the donor) in an excited electron state to another, the chromophore (the acceptor). FRET is distinctive in its ability to reveal the presence of specific recognition of select targets such as the nerve agent stimulant Methyl Salicylate (MES) upon spectroscopic excitation. We introduce a surface imprinted and non-imprinted thin film that underwent AC-Electrospray ionization for donor-acceptor pair(s) bound to InGaP quantum dots and mesoporous silicate nanoparticles. The donor-acceptor pair used in this investigation included MES (donor) and 6-(fluorescein-5-(and-6)- carboxamido) hexanoic acid, succinimidyl ester bound to InGaP quantum dots (acceptor). MES was then investigated as a donor to various acceptor fluorophore: InGaP: mesoporous silicate nanoparticle layers.

  19. Approches par points de vue pour l’ingénierie des Systèmes d’information

    Directory of Open Access Journals (Sweden)

    Brahim Lahna

    2009-07-01

    Full Text Available Les concepts de point de vue, de rôle, de perspective et de vue ont été largement étudiés et utilisés dans de nombreux travaux, dans divers domaines de l’informatique. On retrouve ces notions dans les Systèmes de Représentation de Connaissances par Objets, les Bases de Données Orientées Objets, les Méthodes de Conception, la Programmation Orientée Objets, etc. Chaque domaine lui donne sa propre définition et l’utilise dans son propre contexte. La notion de vue se développe indépendamment dans ces différentes disciplines. Bien que les propositions différent, elles sont confrontées aux mêmes problèmes : établir des relations entre vues et garantir la cohérence des vues entre elles ou vis-à-vis d'un modèle de référence. Nous présentons dans cet article des travaux relatifs aux notions de vues et points de vue dans différentes disciplines informatiques en insistant sur une proposition originale pour une nouvelle ingénierie des systèmes d’information orientée perspectives et composants multivues réutilisables.

  20. SYSTÈMES COMPTABLES DANS LE CONTEXTE DE LA MONDIALISATION

    Directory of Open Access Journals (Sweden)

    Loredana Oana Hutanu (Toma

    2013-09-01

    Full Text Available La comptabilité joue un rôle important dans les politiques économiques nationales et internationales et analysées dans le contexte de la mondialisation économique, l’harmonisation des normes comptables, a donné lieu au fil du temps, à une source continue de controverse. L'évolution de la comptabilité dans le contexte actuel est caractérisée par un phénomène d'harmonisation et de normalisation internationale. Cet article veut faire connaitre au public les deux principaux systèmes comptables existants et leur besoin d'harmonisation.

  1. MES lead bismuth forced circulation loop and test results

    International Nuclear Information System (INIS)

    Ono, Mikinori; Mine, Tatsuya; Kitano, Teruaki; Kamata, Kin-ya

    2003-01-01

    Liquid lead-bismuth is a promising material as future reactor coolant or intensive neutron source material for accelerator driven system (ADS). Mitsui Engineering and Shipbuilding Co., Ltd. (MES) completed lead-bismuth coolant (LBC) forced circulation loop in May 2001 and acquired engineering data on economizer, electro magnetic pump, electro magnetic flow meter and so on. For quality control of LBC, oxygen sensor and filtering element are developing using some hydrogen and moisture mixed gases. Structural materials corrosion test for accelerator driver system (ADS) will start soon. And thermal hydraulic test for ADS will start in tree years. (author)

  2. Architecture, des normes et des systèmes d'information libres, phase ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Architecture, des normes et des systèmes d'information libres, phase II (OASIS II) - Renforcement des capacités dans l'ensemble de l'Afrique. Sur presque tout le continent africain, la prestation des services de santé est limitée en raison des maigres ressources disponibles et de la charge de morbidité de plus en plus ...

  3. Metastable honeycomb SrTiO_3/SrIrO_3 heterostructures

    International Nuclear Information System (INIS)

    Anderson, T. J.; Ryu, S.; Podkaminer, J. P.; Ma, Y.; Eom, C. B.; Zhou, H.; Xie, L.; Irwin, J.; Rzchowski, M. S.; Pan, X. Q.

    2016-01-01

    Recent theory predictions of exotic band topologies in (111) honeycomb perovskite SrIrO_3 layers sandwiched between SrTiO_3 have garnered much attention in the condensed matter physics and materials communities. However, perovskite SrIrO_3 film growth in the (111) direction remains unreported, as efforts to synthesize pure SrIrO_3 on (111) perovskite substrates have yielded films with monoclinic symmetry rather than the perovskite structure required by theory predictions. In this study, we report the synthesis of ultra-thin metastable perovskite SrIrO_3 films capped with SrTiO_3 grown on (111) SrTiO_3 substrates by pulsed laser deposition. The atomic structure of the ultra-thin films was examined with scanning transmission electron microscopy (STEM), which suggests a perovskite layering distinct from the bulk SrIrO_3 monoclinic phase. In-plane 3-fold symmetry for the entire heterostructure was confirmed using synchrotron surface X-ray diffraction to measure symmetry equivalent crystal truncation rods. Our findings demonstrate the ability to stabilize (111) honeycomb perovskite SrIrO_3, which provides an experimental avenue to probe the phenomena predicted for this material system.

  4. Experiences with the determination of Sr-89 and Sr-90 using fast methods; Erfahrungen bei der Bestimmung von {sup 89}Sr und {sup 90}Sr mittels Schnellmethoden

    Energy Technology Data Exchange (ETDEWEB)

    Kowalik, C.; Fueger, J. [Thueringer Landesanstalt fuer Umwelt und Geologie, Jena (Germany). Landesmessstelle fuer Umweltradioaktivaet

    2014-01-20

    Quick methods of the measurement of {sup 89}Sr and {sup 90}Sr have a great importance in the supervision of the environmental radioactivity. It is necessary to receive in short time dependable analytical data to be able to carry out suitable assessments or to give recommendations. The aim of the investigations was to be guaranteed the demands for these methods (test preparation, measurement and evaluation). The use of the solid phase extraction by means of commercial Sr Resin trademark columns (4.4' (5')-Di-tert-butylcyclohexanol-18-kronen-6-aether) (Triskem) to the radiochemical separation of the Sr isotopes was suitable. The measurements occurred to the FHT 770 T12 - Multi Low Level Alpha/Beta Sample Counter (Thermo Scientific). The results contain the summary activities of all available Sr isotopes, as for example {sup 89}Sr and {sup 90}Sr. The calculations of the single activities occur about the mathematical algorithm of the linear development on the basis of the works of G. Kanisch. The first results show, this method is suitable for the analysis of {sup 89}Sr and {sup 90}Sr and is used therefore in future in Thuringia.

  5. PyMEs y crecimiento económico : Estado de situación de Argentina y su comparación con Brasil y Canadá

    OpenAIRE

    De Simone Martin, Mara

    2017-01-01

    Descripción del estado de situación en Argentina, Brasil y Canadá respecto de la contribución de las PyMES al PBI y Empleo. Organismos o políticas de Apoyo a las PyMES. Incubadoras de Negocios. Durante los últimos 15 años, Argentina muestra muy pocas PyMES y bajo PBI comparada con Brasil y Canadá aún cuando se contemplen paralelismos geopolíticos, similitudes en PBI per Cápita (Argentina-Brasil) o PEA (Argentina-Canadá), entre otras muchas otras variables. Argentina no cuenta con un...

  6. Mecanismos para la internacionalización de las PyMES

    OpenAIRE

    Zapata, Cristina I.

    2008-01-01

    Las empresas PyMEs son conscientes de la importancia que el proceso exportador tiene para el crecimiento y muchas veces hasta para su supervivencia. El comercio internacional representa un papel cada vez más relevante en el aporte a la actividad extractiva, industrial y de servicios de un país como Argentina. Las motivaciones y el desarrollo de estrategias de Marketing Internacional son la base para el logro del proceso exportación de las empresas PyME de Argentina. Facultad de Ciencias Ec...

  7. The homes of tomorrow: service composition and advanced user interfaces

    Directory of Open Access Journals (Sweden)

    Claudio Di Ciccio

    2011-12-01

    Full Text Available Home automation represents a growing market in the industrialized world. Today’s systems are mainly based on ad hoc and proprietary solutions, with little to no interoperability and smart integration. However, in a not so distant future, our homes will be equipped with many sensors, actuators and devices, which will collectively expose services, able to smartly interact and integrate, in order to offer complex services providing even richer functionalities. In this paper we present the approach and results of SM4ALL- Smart hoMes for All, a project investigating automatic service composition and advanced user interfaces applied to domotics.

  8. The Intelligent Monitoring System: Generic Database Interface (GDI). User Manual. Revision

    Science.gov (United States)

    1994-01-03

    Summary of Lo=catos Nan* Decufptin Directory Location User Manual FrameMaker ’ source organized inlo, a book UBSW~ftbendb~doclim/user-manual named gdibk A...functions. LNSRCf1bgenrdb/srC I. Framemaker is a docment publishing tool fium Fame Technology Cororation Baseline: 21.1 3-1 anoAW ftnua ?bewd uw on 3.2

  9. Le Machine Learning confronté aux contraintes opérationnelles des systèmes de détection

    OpenAIRE

    Beaugnon , Anaël; Husson , Antoine

    2017-01-01

    International audience; Les systèmes de détection d’intrusion, reposant traditionnellementsur des signatures, n’ont pas échappé à l’attrait récent des techniquesde Machine Learning. Si les résultats présentés dans les articles de rechercheacadémique sont souvent excellents, les experts en sécurité ontcependant encore de nombreuses réticences concernant l’utilisation duMachine Learning dans les systèmes de détection d’intrusion. Ils redoutentgénéralement une inadéquation de ces techniques aux ...

  10. A comparative study of the metastable equilibrium solubility behavior of high-crystallinity and low-crystallinity carbonated apatites using pH and solution strontium as independent variables.

    Science.gov (United States)

    Heslop, D D; Bi, Y; Baig, A A; Otsuka, M; Higuchi, W I

    2005-09-01

    Using solution strontium and pH as independent variables, the metastable equilibrium solubility (MES) behavior of two carbonated apatite (CAP) samples has been examined, a high-crystallinity CAP (properties expected to be similar to dental enamel) and a low-crystallinity CAP (properties expected to be similar to bone mineral). CAP samples were prepared by precipitation/digestion: (CAP A: high-crystallinity, 1.3 wt% CO3, synthesized at 85 degrees C; CAP B: low-crystallinity, 6.4 wt% CO3, synthesized at 50 degrees C). Baseline MES distributions were determined in a series of 0.1 M acetate buffers containing only calcium and phosphate (no strontium) over a broad range of solution conditions. To assess the influence of strontium, MES profiles were determined in a similar fashion with 20, 40, 60, and 80% of the solution calcium being replaced on an equal molar basis by solution strontium. To determine the correct function governing CAP dissolution, ion activity products (IAPs) were calculated from the compositions of buffer solutions based on the hydroxyapatite template (Ca(10-n)Sr(n)(PO4)6(OH)2 (n = 0-10)) and the calcium/hydroxide deficient hydroxyapatite template (Ca(9-n)Sr(n)(HPO4)(PO4)5OH (n = 0-9)). (a) for CAP A, at high solution strontium/calcium ratios, the MES profiles were essentially superimposable when the solution IAPs were calculated using the stoichiometry of Ca6Sr4(PO4)6(OH)2 and for CAP B by a stoichiometry of Ca7Sr2(HPO4)(PO4)5OH; (b) for CAP A, at low strontium/calcium ratios, the stoichiometry yielding MES data superpositioning was found to be that of hydroxyapatite and for CAP B, that of calcium/hydroxide deficient hydroxyapatite. When other stoichiometries were assumed, good superpositioning of the data was not possible.

  11. Operational Based Vision Assessment Automated Vision Test Collection User Guide

    Science.gov (United States)

    2017-05-15

    AFRL-SA-WP-SR-2017-0012 Operational Based Vision Assessment Automated Vision Test Collection User Guide Elizabeth Shoda, Alex...June 2015 – May 2017 4. TITLE AND SUBTITLE Operational Based Vision Assessment Automated Vision Test Collection User Guide 5a. CONTRACT NUMBER... automated vision tests , or AVT. Development of the AVT was required to support threshold-level vision testing capability needed to investigate the

  12. Rapid method for determining Sr-89 and Sr-90 using Cherenkov and proportional counting; Schnellmethode zur Bestimmung von SR-89 und SR-90 durch Cerenkov- und Proportionalzaehlermessungen

    Energy Technology Data Exchange (ETDEWEB)

    Lange, S.; Wende, C.; Schwokowski, R.; Alisch-Mark, M.; Abraham, A.; Heinrich, T. [Staatliche Betriebsgesellschaft fuer Umwelt und Landwirtschaft, Radebeul (Germany)

    2016-07-01

    A rapid method for determining Sr-89 and Sr-90 in water, milk and biological samples has been developed and tested. After sample preparation strontium is separated by extraction chromatography using Sr resin. Eluate is divided and transfered to LSC vial and filter paper by SrCO{sub 3} precipitation. A Hidex 300 SL TDCR liquid scintillation counter and Thermo Fisher low level proportional counter have been used. Chemical yield of Sr-85 tracer is determined by Gamma spectroscopy. Uncertainty budget, decision threshold and detection limit are calculated in accordance with GUM and ISO 11929.

  13. Methylphenidate disintegration from oral formulations for intravenous use by experienced substance users.

    Science.gov (United States)

    Bjarnadottir, G D; Johannsson, M; Magnusson, A; Rafnar, B O; Sigurdsson, E; Steingrimsson, S; Asgrimsson, V; Snorradottir, I; Bragadottir, H; Haraldsson, H M

    2017-09-01

    Methylphenidate (MPH) is a prescription stimulant used to treat attention-deficit hyperactivity disorder. MPH is currently the preferred substance among most intravenous (i.v.) substance users in Iceland. Four types of MPH preparations were available in Iceland at the time of study: Immediate-release (IR), sustained-release (SR), osmotic controlled-release oral delivery (OROS) tablet and osmotic-controlled release (OCR). MPH OROS has previously been rated the least desirable by i.v. users and we hypothesized that this was associated with difficulty of disintegrating MPH from OROS formulation. The aim of the study was to measure the amount of MPH and the viscosity of the disintegrated solutions that were made from the four MPH formulations by four i.v.-users and non-users. A convenience sample of four i.v. substance users and 12 non-users. Non-users imitated the methods applied by experienced i.v. substance users for disintegrated MPH formulations. Both groups managed to disintegrate over 50% of MPH from IR and SR formulations but only 20% from OROS (pusers and non-users. To our knowledge, this is the first investigation of viscosity and the amount of disintegrated MPH from prescription drugs for i.v. use. The results indicate that the ease of disintegration, amount of MPH and viscosity may explain the difference in popularity for i.v. use between different MPH formulations. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Environmental 90Sr measurements

    Science.gov (United States)

    Paul, M.; Berkovits, D.; Cecil, L.D.; Feldstein, H.; Hershkowitz, A.; Kashiv, Y.; Vogt, S.

    1997-01-01

    90Sr (T1/2 = 28.5 years) is a long-lived radionuclide produced in nuclear fission. Fast radiochemical detection of 90Sr in environmental samples is not feasible using current analytical methods. Accelerator Mass Spectrometry (AMS) measurements of 90Sr were made with the Rehovot 14UD Pelletron accelerator at a terminal voltage of 11 or 12 MV using our standard detection system. Injection of hydride ions (SrH3-) was chosen owing to high beam intensity and low Coulomb explosion effects. 90Sr ions were identified and discriminated from isobaric 90Zr by measuring time of flight, total energy and three independent energy-loss signals in an ionization chamber. A reference sample and a ground-water sample were successfully measured. The detection limit determined for a laboratory blank by the residual counts in the 90Sr region is 90Sr/Sr = 3 ?? 10-13, corresponding in practice to (2-4) ?? 10790Sr atoms or about 0.5-1 pCi/L in environmental water samples.

  15. Neodymium-doped Sr5(PO4)3F and Sr5(VO4)3F

    International Nuclear Information System (INIS)

    Corker, D.L.; Nicholls, J.; Loutts, G.B.

    1995-01-01

    Neodymium-doped Sr 5 (PO 4 ) 3 F [neodymium strontium fluoride phosphate, (Nd,Sr) 5 (PO 4 ) 3 F] and neodymium-doped Sr 5 (VO 4 ) 3 F [neodymium strontium fluoride vanadate, (Nd,Sr) 5 (VO 4 ) 3 F] crystallize in space group P6 3 /m and are isostructural with calcium fluorophosphate, Ca 5 (PO 4 ) 3 F. There are two different Sr sites in Sr 5 (XO 4 ) 3 F, denoted Sr(1) and Sr(2). Using single-crystal X-ray diffraction the two structures were refined to R factors of 2.3 and 2.2%, respectively, showing that Nd is present at both Sr sites in (Sr,Nd) 5 (VO 4 ) 3 F but only at the Sr(2) site in (Sr,Nd) 5 (PO 4 ) 3 F. (orig.)

  16. Is the Modern Marine 87Sr/86Sr Cycle Balanced?

    Science.gov (United States)

    Peucker-Ehrenbrink, B.

    2017-12-01

    The marine 87Sr/86Sr record is one of the best-reconstructed isotope records with thousands of high quality measurements spanning the past 800 million years. It records a global signal of tectonic, biotic and climatic processes on Earth. Yet despite decades of research we still do not know whether the current marine Sr budget is in steady state. Studies of the marine 88Sr/86Sr record indicate that sources and sinks do not balance. The magnitude and isotope composition of the terrestrial inputs are being debated, and the magnitude and temporal variability of unradiogenic contributions are not well constrained. Here I provide a revised assessment of all continental sources of Sr to the ocean, including river runoff, submarine groundwater discharge (Beck et al., 2013), dissolution of riverine suspended matter in seawater and dissolution of volcanic ash deposited on the ocean (Jones et al., 2012). I contrast continental sources of Sr with estimates of marine sources of Sr to seawater, specifically high- and low-temperature submarine hydrothermal fluids, as well as diffusive diagenetic fluxes. Best current data imply that unradiogenic submarine hydrothermal inputs to seawater are insufficient to balance the flux of radiogenic continental Sr. The revised assessment of riverine contributions is based on Sr data for almost 230 rivers, an increasing amount of time-series data for such rivers, as well as river discharge and sediment flux data for more than 2000 rivers. Regional sampling biases have been corrected with the aid of digital bedrock maps, specifically along the western margin of North America, East Africa and the large drainage region of Arabia, India and SE Asia. Significant uncertainty in the chemical and isotopic compositions of runoff from Greenland and East Africa remains. The main uncertainty in the budget, however, is related to the possibility that modern rivers do not represent the pre-anthropogenic (natural) state of continental runoff (e.g. Ganges

  17. Experimental autoabsorption curve 90Sr in SrCO3. Efficiency calculation to detection of 90Sr, 90Y and 90Sr + 90Y in a beta gas proportional counter

    International Nuclear Information System (INIS)

    Gasco, C.; Alvarez, A.

    1987-01-01

    Strontium-90 has been determined by radiochemical separation techniques in environmental samples. These techniques, of course, cannot separate the two strontium radionuclides from each other of from stable strontium. Consequently the end product of the chemical separation contains all strontium isotopes in SrCO 3 . The beta particules emitted by 90 Sr are absorbed by the SrCO 3 precipitate. This is the main source of error in the activity measurement. It has been prepared sources of 90 Sr in SrCO 3 in order to determinate the counting efficiency and autoabsorption curve. Also detection efficiencies have been calibrated using known activities of 90 Y and equilibrium mixture of 90 Sr+ 90 Y in the same geometry than our samples. The activity of 90 Sr by ingrowth of 90 Y has been calculated by our computer program. (author). 2 figs., 3 refs

  18. ZASTOSOWANIE FUNKCJONAŁU HU-WASHIZU W PLASTYCZNEJ ANALIZIE MES PŁYT GRUBYCH

    Directory of Open Access Journals (Sweden)

    Jakub LEWANDOWSKI

    2016-07-01

    Full Text Available W pracy sformułowano oryginalny, autorski funkcjonał dla zagadnień teorii plastyczności. Podstawą był funkcjonał Hu-Washizu z teorii sprężystości. Przyrostowa postać funkcjonału pozwala w prosty sposób budować algorytmy MES. Zastosowanie funkcjonału przedstawiono na przykładzie płyty grubej. Zastosowano model warstwowy aby uwzględnić częściowe uplastycznienie przekroju płyty. Algorytm MES dla płyty grubej zbudowano w oparciu o trójkątny trzy węzłowy element skończony z liniowymi funkcjami kształtu dla wszystkich przemieszczeń uogólnionych. Naprężenia i odkształcenia w tego typu elemencie przyjmuje się jako stałe. Przedstawiony algorytm nie wymaga żadnych dodatkowych równań teorii plastyczności i jest równoważny stowarzyszonemu prawu płynięcia plastycznego. Algorytm prowadzi do nieliniowego, przyrostowego układu równań algebraicznych, który rozwiązuje się metodą Newtona. Kilka prostych przykładów pozytywnie weryfikuje przyjęte założenia i stosowane algorytmy.

  19. Isotope ratio 87Sr/86Sr in limestones from Bambui group, Brazil (MG)

    International Nuclear Information System (INIS)

    Kawashita, K.; Mizusaki, A.M.P.; Kiang, C.H.

    1987-01-01

    The Sr composition of ancient seawater can be estimated from the analysis of carbonate rocks and, in some cases, used to estimate the age of the analyzed carbonate. The normalized 87Sr/86Sr ratios in calcium carbonate fractions from 14 core samples in the Bambui Group near Montalvania, MG, were found to range between .7077 and .7280. The higher values are attributable to Sr isotopic exchange between silicate and carbonate phases during diagenesis. The ratio of .7077 obtained in two pure calcium carbonate samples is here suggested as the best aproximation for the 87Sr/86Sr value for the Bambui sea. This ratio is compatible with an age of about 700 Ma., estimated from the published 87Sr/86Sr curve of Veizer and others, an age in accordance with Quadros recent (1987, in preparation) identification of marine acritarchs from the latest Precambrian (Vendian). (author) [pt

  20. Structural and compositional characterization of synthetic (Ca,Sr)-tremolite and (Ca,Sr)-diopside solid solutions

    Science.gov (United States)

    Gottschalk, M.; Najorka, J.; Andrut, M.

    Tremolite (CaxSr1-x)2Mg5[Si8O22/(OH)2] and diopside (CaxSr1-x)Mg[Si2O6] solid solutions have been synthesized hydrothermally in equilibrium with a 1 molar (Ca,Sr)Cl2 aqueous solution at 750°C and 200 MPa. The solid run products have been investigated by optical, electron scanning and high resolution transmission electron microscopy, electron microprobe, X-ray-powder diffraction and Fourier-transform infrared spectroscopy. The synthesized (Ca,Sr)-tremolites are up to 2000 µm long and 30 µm wide, the (Ca,Sr)-diopsides are up to 150 µm long and 20 µm wide. In most runs the tremolites and diopsides are well ordered and chain multiplicity faults are rare. Nearly pure Sr-tremolite (tr0.02Sr-tr0.98) and Sr-diopside (di0.01Sr-di0.99) have been synthesized. A continuous solid solution series, i.e. complete substitution of Sr2+ for Ca2+ on M4-sites exists for (Ca,Sr)-tremolite. Total substitution of Sr2+ for Ca2+ on M2-sites can be assumed for (Ca,Sr)-diopsides. For (Ca,Sr)-tremolites the lattice parameters a, b and β are linear functions of composition and increase with Sr-content whereas c is constant. For the diopside series all 4 lattice parameters are a linear function of composition; a, b, c increase and β decreases with rising Sr-content. The unit cell volume for tremolite increases 3.47% from 906.68 Å3 for tremolite to 938.21 Å3 for Sr-tremolite. For diopside the unit cell volume increases 4.87 % from 439.91 Å3 for diopside to 461.30 Å3 for Sr-diopside. The observed splitting of the OH stretching band in tremolite is caused by different configurations of the next nearest neighbors (multi mode behavior). Resolved single bands can be attributed to the following configurations on the M4-sites: SrSr, SrCa, CaCa and CaMg. The peak positions of these 4 absorption bands are a linear function of composition. They are shifted to lower wavenumbers with increasing Sr-content. No absorption band due to the SrMg configuration on the M4-site is observed. This indicates

  1. MAXDOSE-SR: A routine release atmospheric dose model used at SRS

    International Nuclear Information System (INIS)

    Simpkins, A.A.

    2000-01-01

    MAXDOSE-SR is a PC version of the dosimetry code MAXIGASP, which was used to calculate doses to the maximally exposed offsite individual for routine atmospheric releases of radioactive material at the Savannah River Site (SRS). Complete code description, verification of models, and user's manual have been included in this report. Minimal input is required to run the program, and site specific parameters are used when possible

  2. Diagnostic des systèmes de culture à base de mil [ Pennisetum ...

    African Journals Online (AJOL)

    Objectif : Le présent travail a pour objectif, de faire un état des lieux des systèmes de production à base de mil en Côte d'Ivoire septentrionale afin de proposer de nouvelles pistes d'amélioration. Méthodologie et résultats : L'approche méthodologique s'est reposée sur une enquête auprès des paysans sur le terrain dans ...

  3. CONSIDERACIONES PRÁCTICAS PARA LA GESTIÓN DEL CAPITAL DE TRABAJO EN LAS PyMES INNOVADORAS

    Directory of Open Access Journals (Sweden)

    Hugo Alfonso Vargas Arévalo

    2003-07-01

    Full Text Available Las PyMES se presentan en la actualidad como las principales empresas generadoras de empleo en Colombia. Son además un segmento empresarial de gran importancia por su contribución al PIB. Sin embargo, muchas de ellas adolecen de la gestión necesaria para convertirlas en unidades innovadoras, autosostenibles y en crecimiento. Hay, por ejemplo, una gran dificultad para obtener financiación, para vender, para generar estrategias de asociación, para gestionar recursos humanos. Este artículo se propone unificar algunos conceptos concernientes a la administración de capital de trabajo de las PyMES. Se hace énfasis en la rentabilidad y se aporta un conjunto de recursos estratégicos que puede contribuir a mejorar la gestión de este tipo de empresas en el contexto colombiano.

  4. La science de l’amour dans les poèmes et dans les contes soufis

    Directory of Open Access Journals (Sweden)

    Dr Natália Maria Lopes Nunes

    2011-09-01

    Full Text Available Cet article est le résultat introductoire du travail de recherche sur l’amour divin à partir de deux grands maîtres soufis, Ibn Arabi et Djalal ad Din Rumi, qui ont développé dans leurs poèmes et contes ce qu’on peut appeler la Science de l’Amour. Rumi, considéré comme l'un des maîtres de la "Science de l'Amour", l’a répandue à travers des poèmes mystiques et de la danse des derviches. Ibn Arabi, connu comme le "maître maximum" du Soufisme a saisi la sagesse sur l'amour dans le Traité d’Amour. Les deux amoureux de Dieu, ont exprimé leur sagesse sur l'Amour et la Beauté du Bien-Aimé, l’extase de l'âme dans l'union entre l'homme et Dieu.

  5. PyMes: las grandes organizaciones del mañana, ¿ISO la solucion del hoy?

    Directory of Open Access Journals (Sweden)

    Placeres, A.

    2006-07-01

    Full Text Available In this article, we demonstrate the relevance for the companies in terms of maintaining a high competitive ability with their peers, and taking into account the requirement of their clients, trying to procure better tools based upon their financial capabilities, with particular emphasis on PyMes (small and medium-sized companies. This arises from the fact that in order to grow for a company; it should take into account the commitment and variation in this regard, in their clients. In this article the growth options of PyMes based upon the search for standardization, certification and the implementation of their processes with the aid of standard norms such as ISO 9000 are highlighted. This process should be on the basis of the level of the commitment of all their employees, as in the absence of such commitments, such processes will be viewed as unnecessary costs which will not help the growth of the company.

  6. Verification dosimetry of intravascular 90Sr/90Y source trains

    International Nuclear Information System (INIS)

    Sharma, S.D.; Shanta, A.; Tripathi, U.B.; Bhatt, B.C.

    2001-01-01

    90 Sr/ 90 Y source trains (Novoste Beta-Cath System) are currently under clinical trials in India and abroad for intracoronary brachytherapy for prevention of restenosis. Each source train of the Beta-Cath system is supplied with a source certificate giving dose rate at the reference distance of 2 mm from the centerline of the source train. It is essential that the user should check dose rates of brachytherapy sources before its application on the patients. Dose rates and depth dose measurements for 90 Sr/ 90 Y source trains of active length 40 mm using radiochromic films in a tissue equivalent phantom have been carried out. The objectives of these measurements were (1) to verify the dose rates stated in the source certificate, and (2) to obtain relative depth dose data for treatment planning. This paper presents the results of these measurements

  7. Effect of Wood Aging on Wine Mineral Composition and 87Sr/86Sr Isotopic Ratio.

    Science.gov (United States)

    Kaya, Ayse D; Bruno de Sousa, Raúl; Curvelo-Garcia, António S; Ricardo-da-Silva, Jorge M; Catarino, Sofia

    2017-06-14

    The evolution of mineral composition and wine strontium isotopic ratio 87 Sr/ 86 Sr (Sr IR) during wood aging were investigated. A red wine was aged in stainless steel tanks with French oak staves (Quercus sessiliflora Salisb.), with three industrial scale replicates. Sampling was carried out after 30, 60, and 90 days of aging, and the wines were evaluated in terms of general analysis, phenolic composition, total polysaccharides, multielement composition, and Sr IR. Li, Be, Mg, Al, Sc, Ti, V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Sb, Cs, Ba, Pr, Nd, Sm, Eu, Dy, Ho, Er, Yb, Lu, Tl, and Pb elements and 87 Sr/ 86 Sr were determined by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and Na, K, Ca, and Fe by flame atomic absorption spectrometry (FAAS). Two-way ANOVA was applied to assess wood aging and time effect on Sr IR and mineral composition. Wood aging resulted in significantly higher concentrations of Mg, V, Co, Ni, and Sr. At the end of the aging period, wine exhibited statistically identical Sr IR compared to control. Study suggests that wood aging does not affect 87 Sr/ 86 Sr, not precluding the use of this parameter for wine traceability purposes.

  8. C__Users_HP Pro 2000_Desktop_DAKUO.xps

    African Journals Online (AJOL)

    HP Pro 2000

    Effet du «compost plus» sur le compostage des tiges de cotonnier. EFFET DE ... et Systèmes de Production. RESUME .... systèmes de cultures qui repose sur une gestion rationnelle de la ..... Le respect des recommandations par les paysans ...

  9. Incidencia de microorganismos mesófilos en la producción del agua de bebida envasada

    Directory of Open Access Journals (Sweden)

    Y. R. Corredor

    1994-09-01

    Full Text Available Con el fin de determinar una posible incidencia de microorganismos mesófilos en la producción del agua de bebida envasada, se analizaron los factores más importantes implicados en la producción. Para determinar la calidad del agua, se almacenó en diferentes tipos de envases (policarbonato, vidrio, polietileno de alta densidad (PAD, polietileno de baja densidad (PBD y polipropileno coextruído con polietileno (PCP, y posteriormente se realizaron recuentos totales para microorganismos mesófilos y número más probable paracoliformes totales y Pseudomona aeruginosa obteniéndose menores recuentos en el agua envasada  en vidrio. Posteriormente, se compararon los tratamientos de descontaminación del agua (cloraciónozonización utilizando dos tipos de envase (PBD y PCP, para determinar el material y tratamiento que conservan mejor las características organolépticas-fisicoquimicas y la menor incidencia de microorganismos mesófilos durante el tiempo de almacenamiento del producto. El envase más adecuado es el de PCP de calibre 2,5 con el tratamiento de cloro 0,6 pm; también se demostró que el crecimiento bacteria no fue un producto más del almacenamiento y el tipo de envase, ya que al realizar el muestre0 de los sistemas de producción, el agua fue siempre potable. Finalmente, se realizó un panel de saboreo, obteniéndose una preferencia del 80% de los encuestados, hacia el envase de PCP con el tratamiento de cloro.

  10. Geochronological synthesis of Bahia state and the crustal evolution, based in evolution diagram of Sr and initial rate of Sr87/Sr86

    International Nuclear Information System (INIS)

    Sato, K.

    1986-01-01

    The crustal evolution of the ancient terrains of the State of Bahia, Brazil, is attempted with the aid of Sr isotopic results as natural tracers. Some Nd and Pb isotopic data are also available, and support the main conclusions based on Sr evolution diagrams. The analysis of the Sr evolution diagrams shows that the Archean Terrains are mainly formed by accretion from mantle-derived material, but crustal reworking is indicated by the high initial 87 Sr/ 86 Sr value of the Jequie Complex. The Transamazonian mobile belt include both types of materials, but the 87 Sr/ 86 Sr value, generally lower than those of the Jequie Complex, markes improbable a direct derivation. During Middle and Late Proterozoic, the continental crust was already well consolidated, and reworking of crustal material predominated within the Espinhaco and Brasiliano folded systems [pt

  11. Results of field studies on 90SR and stable SR soil-to-plant transfer

    International Nuclear Information System (INIS)

    Gerzabek, M.H.; Artner, C.; Horak, O.; Mueck, K.

    1992-01-01

    In 1987 and 1988 at 35 sites plants ready to harvest and the corresponding soils (0 - 20 cm) were collected for 90 Sr and stable strontium analyses. Sample preparation and measurement led to a detection limit of 0.008 Bq 90 Sr kg -1 . The 90 Sr-contamination of Austrian soils ranged from 396 to 1998 Bq m -2 . Known from literature the contribution of the Chernobyl fallout amounted to app. 25 % of the total contamination. Stable strontium contents of the soils were between 6 and 62.5 mg kg -1 . Bariumtriethanolamine extracted 17.7 to 62.3 % of the total stable Sr in soil. 90 Sr-concentrations in cereal grains ranged from 0.03 to 0.67 Bq kg -1 (fresh wight) for maize and barley, respectively. The values for other foodstuff were between 0.15 (white cabbage) and 0.91 Bq kg -1 (spinach). Stable strontium contents were between 0.079 mg kg -1 (maize) and 72.5 mg kg -1 (celery shoot). The following mean 90 Sr soil-to-plant transfer factors for cereal grains were obtained: 0.010 (maize), 0.097 (rye), 0.049 (wheat), 0.095 (barley). Transfer factors for straw were up to 50 times higher (maize). The transfer of 90 Sr into vegetables and potatoes reached the same order of magnitude compared to the cereals. In all cases soil-to-plant transfer of stable Sr was clearly lower up to 60 % of the respective values for 90 Sr. Thus natural stable strontium is less plant available than 90 Sr. The influence of soil parameters on the 90 Sr transfer into plants was examinated by correlation analyses. Increasing exchangeable calcium contents of the soils resulted in a significant reduction of Sr soil-to-barley straw transfer. (authors)

  12. Internal bremsstrahlung from 89Sr and 90Sr

    International Nuclear Information System (INIS)

    Sayibaba, T.; Narasimha Murity, K.; Rao, C.R.; Satyaprakash; Gubbi, G.K.

    1987-01-01

    The internal bremsstrahlung (IB) spectra emitted in the beta-decays of 89 Sr and 90 Sr were measured with a HPGe detector and a multichannel analyser along with a standard geometrical set-up. Sufficient care has been taken to avoid spurious effects. After making all the necessary corrections, the experimental results were compared with the corresponding theoretical distributions due to Knipp and Uhlenbeck and Bloch (KUB), Lewis and Ford, Nilsson, and also due to Ford and Martin (detour theory). The total IB yields of intensity and energy from each of the isotopes in the investigated energy regions are also determined and compared with the corresponding theoretical values. The present results of IB from 89 Sr are satisfactorily accounted for by the KUB theory. In the case of 90 Sr the experimental results of IB coincide with the Coulomb-corrected theoretical distibution due to Nilsson in the energy range from 60 keV to 110 keV and Beyond 110 keV, they are found to be in excess over Nilsson's theory as well as the detour theory due to Ford and Martin up to the maximum photon energy studied, namely 350 keV

  13. Effect of Sr/Ti Ratio on the Photocatalytic Properties of SrTiO3

    International Nuclear Information System (INIS)

    Sulaeman, U; Yin, S; Sato, T

    2011-01-01

    Since strontium titanate is a wide gap semiconductor, it requires UV light to generate the photocatalytic activities. Modification of strontium titanate to show photocatalytic activity under visible light irradiation is the essential work to efficiently utilize the sun light energy for environmental application. It is expected that the synthesis of SrTiO 3 with variation of Sr/Ti atomic ratio could induce the defect crystals having unique photocatalytic properties. The SrTiO 3 with various Sr/Ti atomic ratios were synthesized by microwave-assisted solvothermal reaction of SrCl 2 .6H 2 O and Ti(OC 3 H 7 ) 4 in KOH aqueous solutions with different atomic ratios of Sr/Ti. The products were characterized by TG-DTA, XRD and DRS. The photocatalytic activity was determined by DeNO x ability using LED lamps with the wavelengths of 627 nm (red), 530 nm (green), 445 nm (blue) and 390 nm (UV). The nanoparticles of perovskite type SrTiO 3 with the particle size of 30-40 nm were successfully synthesized. The visible light responsive photocatalytic activity was generated by adding excess amount of Sr. The photocatalytic activity in visible light could be enhanced by an increase in the Sr/Ti atomic ratio up to 1.25, indicating that the visible light responsive photocatalytic activity is due to the generation of new band gap between the conduction band and valence band of SrTiO 3 by the formation of oxygen vacancy.

  14. Industry's demand for the BESSY synchrotron radiation (SR): approaches towards interlinking basic scientific research activities and industry

    International Nuclear Information System (INIS)

    Bierhals, R.; Schmoch, U.; Nick, D.; Pilorget, L.; Ritschel, C.; Walter, G.H.

    1994-08-01

    In Germany, industry's demand for synchrotron radiation (SR) is very limited, due to the current macroeconomic situation and the corporate strategy of potential SR users in industry. This is in contrast to the conditions in the USA (and Japan), where industrial enterprises more readily invest in and run their own long-term basic research projects for exploration of potential commercial applications according to their demands, with research goals pursued there and in Germany overlapping to a large extent. It cannot be expected that demand for SR from industry in Germany will ever come up to the level seen in the USA. In Germany, non-university research institutes are most likely to become an important group of potential users of SR. Substantially boosting the demand for SR from industry will need a change of macroeconomic framework conditions affecting the corporate strategy to the effect that industry will more strongly commit itself to and take up responsibility for application-oriented fundamental research and the corresponding technology transfer. This can be achieved by a policy providing both for institutional means and financial incentives. As to near-market, strategic technological developments, establishment of structures allowing direct cooperation of science and technology, for instance in the form of joint ventures, or underwriting agreements and corresponding supervisory boards, seem to be promising. As to basic-research-oriented promotion of research, a technology screening might lead to the selection of technology-relevant research goals, and corresponding financial support from a special fund. Such incentives for cooperative action by technology, science and the government will create novel types of research-industry interfaces in Germany between ''historical'' spheres of autonomy of research of industry and the scientific community. (orig.) [de

  15. Comment utiliser les TIC pour s'attaquer aux problèmes de santé ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    On appelle souvent cybersanté l'utilisation des technologies de l'information et de la communication (TIC) dans les systèmes de santé. L'importance accordée par le CRDI à la fois au renforcement des capacités et à l'influence exercée sur les politiques façonne depuis plus de dix ans les divers projets de recherche en ...

  16. Regional and interspecific variation in Sr, Ca, and Sr/Ca ratios in avian eggshells from the USA.

    Science.gov (United States)

    Mora, Miguel A; Brattin, Bryan; Baxter, Catherine; Rivers, James W

    2011-08-01

    To examine regional variation in strontium (Sr), which at high concentrations may reduce eggshell quality, increase egg breakage and reproductive failure, we analyzed Sr, and calcium (Ca) concentrations and Sr/Ca ratios in eggshells from 20 avian species from California, Texas, Idaho, Kansas, and Michigan. In addition, we included data previously reported from Arizona to expand the regional comparisons and to better establish patterns of Sr, and Sr/Ca ratios in bird species across the United States. We found Sr concentrations varied significantly among regions, among species, and among foraging guilds; this variability is strongly influenced by the Sr/Ca ratios in surface water from locations close to the region where the eggshells were collected. Sr concentrations and Sr/Ca ratios were significantly higher in bird eggshells from the Volta wildlife region in the San Joaquin Valley, California and in various locales from Arizona. Sr concentrations and Sr/Ca ratios in bird eggshells from other locations in the USA were lower than those detected in these two regions. Among foraging guilds, invertivores had the highest Sr concentrations and Sr/Ca ratios and carnivores had the lowest. In general, the Sr/Ca ratio increased strongly with increasing Sr concentrations (R(2) = 0.99, P eggshells suggesting that these values could be determined from Sr/Ca ratios in water. Eggshell thickness was poorly correlated with Sr (R(2) = 0.03) but had a significant and positive correlation with Ca and was more properly correlated by a quadratic equation (R(2) = 0.50, Thickness = 2.13 - 0.02Ca - 3.07 * 10(-5)Ca(2)). Our study provides further evidence that Sr accumulates significantly in the avian eggshell, in some regions at concentrations which could be of concern for potential negative effects on reproduction. We suggest that when assessing the effects of metals on avian reproduction in regions with high Sr deposits in rock and soil, Sr concentrations in the eggshell also should be

  17. IKNO, a user facility for coherent terahertz and UV synchrotron radiation

    International Nuclear Information System (INIS)

    Sannibale, Fernando; Marcelli, Augusto; Innocenzi, Plinio

    2008-01-01

    IKNO (Innovation and KNOwledge) is a proposal for a multi-user facility based on an electron storage ring optimized for the generation of coherent synchrotron radiation (CSR) in the terahertz frequency range, and of broadband incoherent synchrotron radiation (SR) ranging from the IR to the VUV. IKNO can be operated in an ultra-stable CSR mode with photon flux in the terahertz frequency region up to nine orders of magnitude higher than in existing 3rd generation light sources. Simultaneously to the CSR operation, broadband incoherent SR up to VUV frequencies is available at the beamline ports. The main characteristics of the IKNO storage and its performance in terms of CSR and incoherent SR are described in this paper. The proposed location for the infrastructure facility is in Sardinia, Italy

  18. Facile Synthesis of SrCO3-Sr(OH2/PPy Nanocomposite with Enhanced Photocatalytic Activity under Visible Light

    Directory of Open Access Journals (Sweden)

    Alfredo Márquez-Herrera

    2016-01-01

    Full Text Available Pyrrole monomer was chemically polymerized onto SrCO3-Sr(OH2 powders to obtain SrCO3-Sr(OH2/polypyrrole nanocomposite to be used as a candidate for photocatalytic degradation of methylene blue dye (MB. The material was characterized by Fourier transform infrared (FTIR spectroscopy, UV/Vis spectroscopy, and X-ray diffraction (XRD. It was observed from transmission electronic microscopy (TEM analysis that the reported synthesis route allows the production of SrCO3-Sr(OH2 nanoparticles with particle size below 100 nm which were embedded within a semiconducting polypyrrole matrix (PPy. The SrCO3-Sr(OH2 and SrCO3-Sr(OH2/PPy nanocomposites were tested in the photodegradation of MB dye under visible light irradiation. Also, the effects of MB dye initial concentration and the catalyst load on photodegradation efficiency were studied and discussed. Under the same conditions, the efficiency of photodegradation of MB employing the SrCO3-Sr(OH2/PPy nanocomposite increases as compared with that obtained employing the SrCO3-Sr(OH2 nanocomposite.

  19. Coral Sr-U Thermometry

    Science.gov (United States)

    DeCarlo, T. M.; Gaetani, G. A.; Cohen, A. L.; Foster, G. L.; Alpert, A.; Stewart, J.

    2016-12-01

    Coral skeletons archive the past two millennia of climate variability in the oceans with unrivaled temporal resolution. However, extracting accurate temperature information from coral skeletons is confounded by "vital effects", which often override the temperature dependence of geochemical proxies. Here, we present a new approach to coral paleothermometry based on results of abiogenic precipitation experiments interpreted within a framework provided by a quantitative model of the coral biomineralization process. We conducted laboratory experiments to test the temperature and carbonate chemistry controls on abiogenic partitioning of Sr/Ca and U/Ca between aragonite and seawater, and we modeled the sensitivity of skeletal composition to processes occurring at the site of calcification. The model predicts that temperature can be accurately reconstructed from coral skeleton by combining Sr/Ca and U/Ca ratios into a new proxy, Sr-U. We tested the model predictions with measured Sr/Ca and U/Ca ratios of fourteen Porites sp. corals collected from the tropical Pacific Ocean and the Red Sea, with a subset also analyzed using the boron isotope (δ11B) pH proxy. Observed relationships among Sr/Ca, U/Ca, and δ11B agree with model predictions, indicating that the model accounts for the key features of the coral biomineralization process. We calibrated Sr-U to instrumental temperature records and found that it captures 93% of mean annual variability (26-30 °C) and predicts temperature within 0.5 °C (1 σ). Conversely, Sr/Ca alone has an error of prediction of 1 °C and often diverges from observed temperature by 3 °C or more. Many of the problems afflicting Sr/Ca - including offsets among neighboring corals and decouplings from temperature during coral stress events - are reconciled by Sr-U. By accounting for the influence of the coral biomineralization process, the Sr-U thermometer may offer significantly improved reliability for reconstructing ocean temperatures from coral

  20. Solar Thermochemical Energy Storage Through Carbonation Cycles of SrCO3/SrO Supported on SrZrO3.

    Science.gov (United States)

    Rhodes, Nathan R; Barde, Amey; Randhir, Kelvin; Li, Like; Hahn, David W; Mei, Renwei; Klausner, James F; AuYeung, Nick

    2015-11-01

    Solar thermochemical energy storage has enormous potential for enabling cost-effective concentrated solar power (CSP). A thermochemical storage system based on a SrO/SrCO3 carbonation cycle offers the ability to store and release high temperature (≈1200 °C) heat. The energy density of SrCO3/SrO systems supported by zirconia-based sintering inhibitors was investigated for 15 cycles of exothermic carbonation at 1150 °C followed by decomposition at 1235 °C. A sample with 40 wt % of SrO supported by yttria-stabilized zirconia (YSZ) shows good energy storage stability at 1450 MJ m(-3) over fifteen cycles at the same cycling temperatures. After further testing over 45 cycles, a decrease in energy storage capacity to 1260 MJ m(-3) is observed during the final cycle. The decrease is due to slowing carbonation kinetics, and the original value of energy density may be obtained by lengthening the carbonation steps. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. CHARACTERIZATION OF THE PARTIALLY PURIFIED PLANTARCIN SR18 PRODUCED BY LACTOBACILLUS PLANTARUM SR18

    Directory of Open Access Journals (Sweden)

    Wagih El-Shouny

    2013-04-01

    Full Text Available The bacteriocin bound to the cells and that secreted into the culture filtrate of Lactobacillus plantarum SR18 were precipitated by 75% ammomium sulphate, dialysed and further purified by Gel filtration on Sephadex G-100. Bacteriocins were purified from proteins bound to the cell of L. plantarum SR18 (plantarcin SR18 a and culture filtrate proteins (plantarcin SR18 b, respectively. The SDS-PAGE of partially purified Plantarcin SR18a showed a molecular weight of 3.5 KDa. While, plantarcin SR18 b had a molecular weight of 10.3 KDa. The antibacterial activity of the tested plantarcin SR18 preparations suffered no measurable loss after 45 min at 80ºC. Whereas, At 100ºC, significant decrease in the activity of bacteriocin preparations (60- 80 % took place by the end of 45 min. At pH ranged from 5-8, the activity of the plantarcin SR18 preparations suffered no measurable loss. Dissociating agents significantly affected the bacteriocin activity. Thus, tween 80 and mercaptoethanol increased the activity of bacteriocin preparations to 1.2-1.4 fold. Sodium dodecyl sulphate (SDS increased the activity of the tested bacteriocin preparations by about 20%.The lowest residual activity (60% was recorded after treatment with Triton X100 for 45 min. Protease completely inhibited the activities of all forms of plantarcin SR18 after 45 min at 37ºC.

  2. La recherche-action participative appliquée aux systèmes de santé ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    4 déc. 2014 ... Une nouvelle publication, intitulée Participatory Action Research in Health Systems: a methods reader, a été lancée à l'occasion du troisième Symposium mondial sur la recherche sur les systèmes de santé, qui s'est tenu au Cap, en Afrique du Sud, du 30 septembre au 3 octobre 2014. Ce guide des ...

  3. Magnetism in the p-type Monolayer II-VI semiconductors SrS and SrSe

    Science.gov (United States)

    Lin, Heng-Fu; Lau, Woon-Ming; Zhao, Jijun

    2017-01-01

    Using density functional theory calculations, we study the electronic and magnetic properties of the p-type monolayer II-VI semiconductors SrX (X = S,Se). The pristine SrS and SrSe monolayers are large band gap semiconductor with a very flat band in the top valence band. Upon injecting hole uniformly, ferromagnetism emerges in those system in a large range of hole density. By varying hole density, the systems also show complicated phases transition among nonmagnetic semiconductor, half metal, magnetic semiconductor, and nonmagnetic metal. Furthermore, after introducing p-type dopants in SrS and SrSe via substitutionary inserting P (or As) dopants at the S (or Se) sites, local magnetic moments are formed around the substitutional sites. The local magnetic moments are stable with the ferromagnetic order with appreciable Curie temperature. The ferromagnetism originates from the instability of the electronic states in SrS and SrSe with the large density of states at the valence band edge, which demonstrates a useful strategy for realizing the ferromagnetism in the two dimensional semiconductors. PMID:28378761

  4. Protective Effects of an Ancient Chinese Kidney-Tonifying Formula against H2O2-Induced Oxidative Damage to MES23.5 Cells.

    Science.gov (United States)

    Xu, Yihui; Lin, Wei; Ye, Shuifen; Wang, Huajin; Wang, Tingting; Su, Youyan; Wu, Liangning; Wang, Yuanwang; Xu, Qian; Xu, Chuanshan; Cai, Jing

    2017-01-01

    Oxidative damage plays a critical role in the etiology of neurodegenerative disorders including Parkinson's disease (PD). In our study, an ancient Chinese kidney-tonifying formula, which consists of Cistanche , Epimedii, and Polygonatum cirrhifolium , was investigated to protect MES23.5 dopaminergic neurons against hydrogen peroxide- (H 2 O 2 -) induced oxidative damage. The damage effects of H 2 O 2 on MES23.5 cells and the protective effects of KTF against oxidative stress were evaluated using MTT assay, transmission electron microscopy (TEM), immunocytochemistry (ICC), enzyme-linked immunosorbent assay (ELISA), and immunoblotting. The results showed that cell viability was dramatically decreased after a 12 h exposure to 150  μ M H 2 O 2 . TEM observation found that the H 2 O 2 -treated MES23.5 cells presented cellular organelle damage. However, when cells were incubated with KTF (3.125, 6.25, and 12.5  μ g/ml) for 24 h after H 2 O 2 exposure, a significant protective effect against H 2 O 2 -induced damage was observed in MES23.5 cells. Using ICC, we found that KTF inhibited the reduction of the tyrosine hydroxylase (TH) induced by H 2 O 2 , upregulated the mRNA and protein expression of HO-1, CAT, and GPx-1, and downregulated the expression of caspase 3. These results indicated that KTF may provide neuron protection against H 2 O 2 -induced cell damage through ameliorating oxidative stress, and our findings provide a new potential strategy for the prevention and treatment of Parkinson's disease.

  5. Electronic parameters of Sr2M2O7 (M = V, Nb, Ta) and Sr-O chemical bonding

    DEFF Research Database (Denmark)

    Atuchin, Victor V.; Grivel, Jean-Claude; Zhang, Zhaoming

    2010-01-01

    XPS measurements were carried out on Sr2Nb2O7 and Sr2Ta2O7 powder samples, which were synthesized using standard solid state method. The binding energy differences between the O 1s and cation core level, Δ(O-Sr) = BE(O 1s) - BE(Sr 3d5/2), was used to characterize the valence electron transfer...... on the formation of the Sr-O bonds. The chemical bonding effects were considered on the basis of our XPS results for Sr2Nb2O7 and Sr2Ta2O7 and the previously published structural and XPS data for other Sr-oxide compounds. A new empirical relationship between Δ(O-Sr) and L(Sr-O) was obtained. Possible applications...

  6. Systematic variations of 87Sr/56Sr ratios, Sr compositions, selected major-oxide concentrations, and mineral abundances in piston cores from the Red Sea

    International Nuclear Information System (INIS)

    Boger, P.D.; Boger, J.L.; Faure, G.

    1980-01-01

    A mixing model is presented which relates the concentrations of Sr to the 87 Sr/ 86 Sr ratios and concentrations of other elements contained in a mixture of two components. The model is applied to the measured 87 Sr/ 86 Sr ratios, Sr, CaO, Fe 2 O 3 and SiO 2 concentrations of the detrital fractions of sediment from three piston cores representing different depositional environments in the Red Sea. The sediment is shown to be a mixture of two components derived from old sialic rocks and young volcanic rocks of the surrounding land masses. One of the cores contained a third component which is identified as authigenic Fe 2 O 3 . Removal of this contaminant is shown to return the system to its original detrital constituents. (Auth.)

  7. Addition to the analysis of the Sr VI and Sr VII spectra

    International Nuclear Information System (INIS)

    Wyart, J.F.

    1989-01-01

    Fifty-six lines of multicharged strontium are measured with an improved wavelength accuracy, or interpreted for the first time. They are 4p-4s, 4p-5s and 4p-4d transitions in Sr VII and 4p-5s transitions in Sr VI. The revision of the singlet-triplet connection in Sr VII is supported by theoretical survey of the ground configuration in Ge-like ions. (orig.)

  8. Évaluation des services rendus par les écosystèmes  en France

    Directory of Open Access Journals (Sweden)

    Philippe Blancher

    2011-12-01

    Full Text Available Cet article rend compte de la méthode d’évaluation des services écosystémiques appliquée au territoire français dans le cadre d’une approche exploratoire. S’inscrivant dans le sillage du ‘‘Millennium Ecosystem Assessment’’ (MA lancé par l’ONU, l’application de la démarche du MA à un territoire donné a conduit à l’élaboration de nouveaux outils d’analyse et de mesure des interactions entre nature et activités humaines à plusieurs échelles territoriales, à travers une projection cartographique des écosystèmes sur l’ensemble du territoire, un recensement des services rendus par les écosystèmes en France et une méthodologie pour leur quantification.This article introduces a method for the assessment of ecosystem services on the French territory. Following the U.N.-initiated Millennium Ecosystem Assessment framework, the implementation of an ecosystem assessment on a specific territory led to the conception of new tools for the analysis and the measurement of interactions between nature and human activities at different territorial scales, through the mapping of ecosystems, an identification of ecosystem services on the French territory and a methodology for their quantification.

  9. Strontium (Sr) separation from seawater using titanate adsorbents: Effects of seawater matrix ions on Sr sorption behavior

    Science.gov (United States)

    Ryu, Jungho; Hong, Hye-jin; Ryu, Taegong; Park, In-Su

    2017-04-01

    Strontium (Sr) which has many industrial applications such as ferrite magnet, ceramic, and fire works exists in seawater with the concentration of approximately 7 mg/L. In previous report estimating economic potential on recovery of various elements from seawater in terms of their commercial values and concentrations in seawater, Sr locates upper than approximate break-even line, which implies Sr recovery from seawater can be potentially profitable. Recently, Sr separation from seawater has received great attention in the environmental aspect after Fukushima Nuclear Power Plant (NPP) accident which released much amount of radioactive Sr and Cs. Accordingly, the efficient separation of radioactive elements released to seawater has become critical as an important technological need as well as their removal from radioactive wastes. So far, it has been introduced to separate Sr from aqueous media by various methods including solvent extraction, adsorption by solid materials, and ion exchange. Among them, the adsorption technique using solid adsorbents is of great interest for selectively separating Sr from seawater with respect to low concentration level of Sr. In this study, we synthesized titanate nanotube (TiNT) by simple hydrothermal reaction, characterized its physicochemical properties, and systematically evaluated Sr sorption behavior under various reaction conditions corresponding to seawater environment. The synthesized TiNT exhibited the fibril-type nanotube structure with high specific surface area of 260 m2/g. The adsorption of Sr on TiNT rapidly occurred following pseudo-second-order kinetic model, and was in good agreement with Langmuir isotherm model, indicating maximum adsorption capacity of 97 mg/g. Based on Sr uptake and Na release with stoichiometric balance, sorption mechanism of Sr on TiNT was found to be ion-exchange between Na in TiNT lattice and Sr in solution phase, which was also confirmed by XRD and Raman analysis. Among competitive ions, Ca

  10. Input of 87Sr/86Sr ratios and Sr geochemical signatures to update knowledge on thermal and mineral waters flow paths in fractured rocks (N-Portugal)

    International Nuclear Information System (INIS)

    Marques, J.M.; Carreira, P.M.; Goff, F.; Eggenkamp, H.G.M.; Antunes da Silva, M.

    2012-01-01

    Strontium isotopes and other geochemical signatures are used to determine the relationships between CO 2 -rich thermal (Chaves: 76 °C) and mineral (Vilarelho da Raia, Vidago and Pedras Salgadas: 17 °C) waters discharging along one of the major NNE–SSW trending faults in the northern part of mainland Portugal. The regional geology consists of Hercynian granites (syn-tectonic-310 Ma and post-tectonic-290 Ma) intruding Silurian metasediments (quartzites, phyllites and carbonaceous slates). Thermal and mineral waters have 87 Sr/ 86 Sr isotopic ratios between 0.716713 and 0.728035. 87 Sr/ 86 Sr vs. 1/Sr define three end-members (Vilarelho da Raia/Chaves, Vidago and Pedras Salgadas thermal and mineral waters) trending from rainfall composition towards that of the CO 2 -rich thermal and mineral waters, indicating different underground flow paths. Local granitic rocks have 87 Sr/ 86 Sr ratios of 0.735697–0.789683. There is no indication that equilibrium was reached between the CO 2 -rich thermal and mineral waters and the granitic rocks. The mean 87 Sr/ 86 Sr ratio of the thermal and mineral waters (0.722419) is similar to the Sr isotopic ratios of the plagioclases of the granitic rocks (0.71261–0.72087). The spatial distribution of Sr isotope and geochemical signatures of waters and the host rocks suggests that the thermal and mineral waters circulate in similar but not the same hydrogeological system. Results from this study could be used to evaluate the applicability of this isotope approach in other hydrogeologic investigations.

  11. A high 87Sr 86Sr mantle source for low alkali tholeiite, northern Great Basin

    Science.gov (United States)

    Mark, R.K.; Lee, Hu C.; Bowman, H.R.; Asaro, F.; McKee, E.H.; Coats, R.R.

    1975-01-01

    Olivine tholeiites, the youngest Tertiary units (about 8-11 m.y. old) at five widely spaced localities in northeastern Nevada, are geologically related to the basalts of the Snake River Plain, Idaho, to the north and are similar in major element and alkali chemistry to mid-ocean ridge basalts (MORB) and island arc tholeiites. The measured K (1250-3350 ppm), Rb (1??9-6??2 ppm) and Sr (140-240 ppm) concentrations overlap the range reported for MORB. Three of the five samples have low, unfractionated rare earth element (REE) patterns, the other two show moderate light-REE enrichment. Barium concentration is high and variable (100-780 ppm) and does not correlate with the other LIL elements. The rocks have 87Sr/86Sr = 0??7052-0??7076, considerably higher than MORB (~0??702-0??703). These samples are chemically distinct (i.e. less alkalic) from the olivine tholeiites from the adjacent Snake River Plain, but their Sr isotopic compositions are similar. They contain Sr that is distinctly more radiogenic than the basalts from the adjacent Great Basin. About 10 b.y. would be required for the mean measured Rb/Sr (~ 0??02) of these samples to generate, in a closed system, the radiogenic Sr they contain. The low alkali content of these basalts makes crustal contamination an unlikely mechanism. If the magma is uncontaminated, the time-averaged Rb/Sr of the source material must have been ~0??04. A significant decrease in Rb/Sr of the source material (a factor 2??) thus most probably occurred in the relatively recent (1??09 yr) past. Such a decrease of Rb/Sr in the mantle could accompany alkali depletion produced by an episode of partial melting and magma extraction. In contrast, low 87Sr 86Sr ratios indicate that the source material of the mid-ocean ridge basalts may have been depleted early in the Earth's history. ?? 1975.

  12. Agent des systèmes d'information financière (h/f) | CRDI - Centre de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Répondre directement aux demandes des utilisateurs formulées par courriel ou par téléphone ou par l'entremise du système de gestion des appels de dépannage. Communiquer au besoin avec les fournisseurs de logiciels et le personnel responsable des TI pour régler les problèmes rencontrés par les utilisateurs finaux ...

  13. Variables que influyen en el comportamiento de la lactancia materna exclusiva hasta el sexto mes

    Directory of Open Access Journals (Sweden)

    William Cáceres Fernández

    Full Text Available Introducción: la lactancia materna exclusiva hasta los 6 meses se considera la alimentación ideal para el recién nacido, pues se ha demostrado que garantiza el crecimiento y desarrollo, previene enfermedades frecuentes en la infancia y en la edad adulta, y brinda múltiples ventajas para los niños y las madres. Objetivo: determinar algunas variables que influyen en el comportamiento de la lactancia materna exclusiva hasta el 6to mes de vida del recién nacido. Métodos: se realizó un estudio descriptivo retrospectivo a través de la aplicación de una encuesta a 56 madres de niños mayores de 6 meses, pertenecientes a 4 consultorios del médico de la familia del policlínico «Héroes del Moncada», en el periodo comprendido desde enero hasta diciembre de 2012. Se tomaron los datos necesarios de la madre y el niño mediante la aplicación de una encuesta y se vaciaron en un formulario elaborado al efecto. Resultados: el grupo de edad de 20-35 años fue el que predominó en las madres que mantuvieron la lactancia materna exclusiva hasta el sexto mes, con un 73,2 %; fueron las madres con nivel universitario (21,4 % las que tenían más conocimiento sobre las ventajas de la lactancia materna. En el 42,3 % de los casos se interrumpió la lactancia materna exclusiva por la incorporación al trabajo; y se enfermaron más aquellos niños que interrumpieron la lactancia. Conclusiones: existen factores como la edad menor de 20 ó mayor de 35 años, el bajo nivel cultural y la necesidad de reincorporación al trabajo, que atentan contra mantener una lactancia materna exclusiva hasta el sexto mes de vida del recién nacido.

  14. 87Sr/86Sr isotope fingerprinting of Scottish and Icelandic migratory shorebirds

    International Nuclear Information System (INIS)

    Evans, Jane; Bullman, Rhys

    2009-01-01

    Biosphere Sr isotope composition data from Iceland and Scotland suggest that terrestrially feeding birds from these two countries will have significantly different 87 Sr/ 86 Sr isotope composition in their tissues. The aim of this study is to test if these differences can be measured within the bone and feather of migratory wading birds, who feed terrestrially as juveniles, thus providing a provenance tool for these birds. The study shows that birds can be distinguished on the basis of the Sr isotope composition of their bone. The field for Icelandic birds is defined by data from juvenile common redshank (Tringa totanus) and whimbrel (Numenius phaeopus) which give 0.7056 ± 0.0012, (2σ, n = 7). The majority of Scottish birds in this study are from coastal regions and have a signature close to that of seawater of 0.7095 ± 0.0006 (2σ, n = 9). The Sr ratios in the body tissue of these two populations of all Icelandic and Scottish adult and juvenile birds analysed are significantly different (p 87 Sr/ 86 Sr values as high as 0.7194 which reflect their non-marine diet. Icelandic redshank (Tringa totanus robusta) that have flown to Scotland and returned to Iceland show the effect of the Scottish contribution to their diet with elevated values of 0.7086 ± 0.0004, (2σ, n = 6). Redshank found in Scotland that cannot be classified on the basis biometric analysis are shown to be of Icelandic origin and analysis of the primary feathers from two birds demonstrates that isotope variation between feathers could be used to track changes in diet related to the timing of individual feather growth.

  15. Transport of Sr 2+ and SrEDTA 2- in partially-saturated and heterogeneous sediments

    Science.gov (United States)

    Pace, M. N.; Mayes, M. A.; Jardine, P. M.; McKay, L. D.; Yin, X. L.; Mehlhorn, T. L.; Liu, Q.; Gürleyük, H.

    2007-05-01

    Strontium-90 has migrated deep into the unsaturated subsurface beneath leaking storage tanks in the Waste Management Areas (WMA) at the U.S. Department of Energy's (DOE) Hanford Reservation. Faster than expected transport of contaminants in the vadose zone is typically attributed to either physical hydrologic processes such as development of preferential flow pathways, or to geochemical processes such as the formation of stable, anionic complexes with organic chelates, e.g., ethylenediaminetetraacetic acid (EDTA). The goal of this paper is to determine whether hydrological processes in the Hanford sediments can influence the geochemistry of the system and hence control transport of Sr 2+ and SrEDTA 2-. The study used batch isotherms, saturated packed column experiments, and an unsaturated transport experiment in an undisturbed core. Isotherms and repacked column experiments suggested that the SrEDTA 2- complex was unstable in the presence of Hanford sediments, resulting in dissociation and transport of Sr 2+ as a divalent cation. A decrease in sorption with increasing solid:solution ratio for Sr 2+ and SrEDTA 2- suggested mineral dissolution resulted in competition for sorption sites and the formation of stable aqueous complexes. This was confirmed by detection of MgEDTA 2-, MnEDTA 2-, PbEDTA 2-, and unidentified Sr and Ca complexes. Displacement of Sr 2+ through a partially-saturated undisturbed core resulted in less retardation and more irreversible sorption than was observed in the saturated repacked columns, and model results suggested a significant reservoir (49%) of immobile water was present during transport through the heterogeneous layered sediments. The undisturbed core was subsequently disassembled along distinct bedding planes and subjected to sequential extractions. Strontium was unequally distributed between carbonates (49%), ion exchange sites (37%), and the oxide (14%) fraction. An inverse relationship between mass wetness and Sr suggested that

  16. Reactivity of Cubane-Type [(OC)(3)MFe(3)S(4)(SR)(3)](3-) Clusters (M = Mo, W): Interconversion with Cuboidal [Fe(3)S(4)](0) Clusters and Electron Transfer.

    Science.gov (United States)

    Raebiger, James W.; Crawford, Charles A.; Zhou, Jian; Holm, R. H.

    1997-03-12

    The title clusters, several examples of which have been reported earlier, have been prepared by two different methods and subjected to structural and reactivity studies. The compounds (Et(4)N)(3)[(OC)(3)MFe(3)S(4)(Smes)(3)].MeCN (M = Mo/W) are isomorphous and crystallize in monoclinic space group P2(1)/n with a = 13.412(1)/13.297(1) Å, b = 19.0380(1)/18.9376(3) Å, c = 26.4210(1)/26.2949(1) Å, beta = 97.87(1)/97.549(1) degrees, and Z = 4. The clusters contain long M-S (2.62/2.59 Å) and M-Fe (3.22/3.19 Å) bonds, consistent with the reported structure of [(OC)(3)MoFe(3)S(4)(SEt)(3)](3-) (3). Reaction of [(OC)(3)MoFe(3)S(4)(LS(3))](3-) (7) with CO in the presence of NaPF(6) affords cuboidal [Fe(3)S(4)(LS(3))](3-) (9), also prepared in this laboratory by another route as a synthetic analogue of protein-bound [Fe(3)S(4)](0) clusters. The clusters [Fe(3)S(4)(SR)(3)](3-) (R = mes, Et), of limited stability, were generated by the same reaction. Treatment of 9 with [M(CO)(3)(MeCN)(3)] affords 7 and its M = W analogue. The clusters [(OC)(3)MFe(3)S(4)(SR)(3)](3-) form a four-member electron transfer series in which the 3- cluster can be once reduced (4-) and twice oxidized (2-, 1-) to afford clusters of the indicated charges. The correct assignment of redox couple to potential in the redox series of six clusters is presented, correcting an earlier misassignment of the redox series of 3. Carbonyl stretching frequencies are shown to be sensitive to cluster oxidation state, showing that the M sites and Fe(3)S(4) fragments are electronically coupled despite the long bond distances. (LS(3) = 1,3,5-tris((4,6-dimethyl-3-mercaptophenyl)thio)-2,4,6-tris(p-tolylthio)benzenate(3-); mes = mesityl.)

  17. A graphical user-interface control system at SRRC

    International Nuclear Information System (INIS)

    Chen, J.S.; Wang, C.J.; Chen, S.J.; Jan, G.J.

    1993-01-01

    A graphical user interface control system of 1.3 GeV synchrotron radiation light source was designed and implemented for the beam transport line (BTL) and storage ring (SR). A modern control technique has been used to implement and control the third generation synchrotron light source. Two level computer hardware configuration, that includes process and console computers as a top level and VME based intelligent local controller as a bottom level, was setup and tested. Both level computers are linked by high speed Ethernet data communication network. A database includes static and dynamic databases as well as access routines were developed. In order to commission and operate the machine friendly, the graphical man machine interface was designed and coded. The graphical user interface (GUI) software was installed on VAX workstations for the BTL and SR at the Synchrotron Radiation Research Center (SRRC). The over all performance has been evaluated at 10Hz update rate. The results showed that the graphical operator interface control system is versatile system and can be implemented into the control system of the accelerator. It will provide the tool to control and monitor the equipments of the radiation light source especially for machine commissioning and operation

  18. PEMANFAATAN METIL ESTER JARAK PAGAR MENJADI SURFAKTAN MES UNTUK APLIKASI SEBAGAI OIL WELL STIMULATION AGENT

    Directory of Open Access Journals (Sweden)

    Erliza Hambali

    2012-04-01

    Full Text Available Year by year, globally the production of petroleum decreases but its demand increases. The world will get the energy crisis including Indonesia if that condition happens continously. Because of that, Indonesia starts to develop IOR (improved oil recovery method for their oil fields. IOR method is an improvement of the secondary phase in which the oil recovery is expected to increase oil production. One method of IOR is chemical injection with surfactant for injection. Surfactant is dissolved with injection water and injected to reservoir. Generally, surfactant of petroleum sulphonates is used for oil recovery. Due to the weaknesses of petroleum suphonates such as not resistant in high salinity and high hardness water, therefore it triggers to get surfactant substitute like MES (methyl ester sulphonates that is synthesized by bio-oil from Jatropha curcas L. The study was aimed to know the performance of MES surfactant formula from jatropha oil for IOR in fluid sample of oil field and synthetic sandstone core. The best condition from this research was surfactant 0.2 PV with the soaking time of 12 hours. This formula gave the highest of incremental total oil recovery 61%. The number were resulted from 48% waterflooding and 13% surfactant injection.

  19. Solvation consequences of polymer PVP with biological buffers MES, MOPS, and MOPSO in aqueous solutions

    International Nuclear Information System (INIS)

    Gupta, Bhupender S.; Chen, Bo-Ren; Lee, Ming-Jer

    2015-01-01

    Highlights: • Densities and viscosities data for aqueous solutions with PVP and/or buffer. • The studied buffers include MES, MOPS, and MOPSO. • DFT was used to estimate the binding energies of the (PVP + buffer) complexes. • The viscosity data were correlated with the Jones–Dole equation. • The investigated buffers behave as Kosmotropies. - Abstract: Densities and viscosities were measured for the aqueous buffer (MES, MOPS, or MOPSO) solutions containing different concentrations of polyvinylpyrrolidone (PVP) (5, 10, 15, 20 and 30) mass% at temperatures from (298.15 to 318.15) K under atmospheric pressure. The DFT calculations were also performed and the binding energies of the possible (PVP + buffer) complexes were obtained. The experimental and computational results reveal the interactions of the PVP with the constituent compounds in the aqueous buffer solutions. Additionally we have explored the solvation behavior of the buffers by measuring the densities and the viscosities data of the aqueous buffer solutions from (0.0 to 1.0) mol · kg"−"1 at temperatures from (298.15 to 318.15) K. The viscosity results were correlated with the Jones–Dole equation. The correlated results confirmed that all the investigated buffers behave as Kosmotropes (structure makers).

  20. Thermodynamic assessment of the Pb-Sr system

    Directory of Open Access Journals (Sweden)

    Zhang H.

    2017-01-01

    Full Text Available The Pb-Sr system has been critically reviewed and modeled by means of the CALPHAD (CALculation of PHAse Diagrams approach. It contains seven stoichiometric compounds, i.e. SrPb3, Sr3Pb5, Sr2Pb3, SrPb, Sr5Pb4, Sr5Pb3 and Sr2Pb, in which the SrPb3 and Sr2Pb phases melt congruently, and the other five phases form via peritectic reactions. The enthalpies of formation for the intermetallic compounds at 0 K are provided by first-principles calculations. The liquid, fcc and bcc phases are modeled as substitutional solution phases. Both Redlich-Kister and exponential polynomials are used to describe the excess Gibbs energy of the liquid. Two sets of self-consistent thermodynamic parameters are obtained by considering reliable experimental data and the computed enthalpies of formation. Comprehensive comparisons between the calculated and measured phase diagram and thermodynamic data show that the experimental information is satisfactorily accounted for by the present thermodynamic description.

  1. System of Sr(NO2)2-Sr(OH)2-H2O at 25 deg C

    International Nuclear Information System (INIS)

    Popova, T.B.; Berdyukova, V.A.; Khutsistova, F.M.

    1990-01-01

    Sr(NO 2 ) 2 -Sr(OH) 2 -H 2 O system was investigated by the methods of solubility, density, viscosity, electric conductivity and refractometry. It was established that its compoments form the compound 4Sr(NO 2 ) 2 xSr(OH) 2 x8H 2 O. The compound was separated from solution; its density, decomposition temperature were determined; IR spectra and X-ray patterns of prepared and initial compounds were obtained

  2. C, Sr and Sr isotopic composition on probable vendian- tommotian carbonate sequences in Nw Argentina

    International Nuclear Information System (INIS)

    Sial, A. N.; Ferreira, V.P; Toselli, A.J.; Acenolaza, F.G; Pimentel, M.M; Parada, M.A; Alonso, R.N

    2001-01-01

    C-isotope stratigraphy is one of the most powerfool tools in Precambrian chronostratigraphy, especially when sediments lack recognizable animal fossils. The δ 13 C secular variation curves for marine carbonates in the Neoproterozoic-Cambrian interval show strong positive-negative excursions, several of them interpreted as the stratigraphic position of ancient ice ages (Hoffman et al. 1998). The Sr isotope composition of the seawater for this age interval is characterized by a continuous increase of 87 Sr/ 86 Sr that is interrupted, several times, by sharp rises, which represent important changes in the Earth history (Montanez et al. 2000). Only limited data on the behavior of C and Sr isotopes in carbonates are available in South America. We examine here carbonate sequences from the Argentine Precordillera, San Juan province, and from other carbonate sequences in NW Argentina that could be, potentially, proxies for the Precambrian-Cambrian transition. We have studied their δ 13 C and 87 Sr/ 86 Sr chemostratigraphy and compare it to global C and Sr isotope secular variation curves for this time span. This study aims to improve the relatively coarse stratigraphic resolution provided only by the study of the fossil record in some of the carbonate successions under consideration (au)

  3. Résister : les poèmes de guerre de Charles Camproux

    OpenAIRE

    Lassaque, Aurélia

    2014-01-01

    Charles Camproux, né à Marseille en 1908, fut publiquement reconnu comme poète suite à la parution des Poemas sens poesia. Ce premier recueil portant sur la captivité, composé « sot lo ceu d’Alemanha », fut publié peu après le retour de Camproux en France, par les soins d’Ismaël Girard à la SEO en 1942. Camproux composa au cours des deux années suivantes un ensemble de poèmes réunis tardivement sous le titre de Poëmas de Resistència. Contrairement à L’an quaranta e tres et au Bestiari, écrits...

  4. Measurement of resonance integral of the 90Sr(n,γ)91Sr reaction

    International Nuclear Information System (INIS)

    Nakamura, Shoji; Furutaka, Kazuyoshi; Wada, Hiroaki; Katoh, Toshio; Harada, Hideo; Fujii, Toshiyuki; Yamana, Hajimu

    2001-01-01

    To obtain fundamental data for research on nuclear transmutation method of radioactive wastes, the resonance integral (I 0 ) of the 90 Sr(n,γ) 91 Sr reaction was measured with an activation method. (author)

  5. FEP report for the safety assessment SR-Site

    Energy Technology Data Exchange (ETDEWEB)

    2010-12-15

    This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Site, and forms an important part of the reporting of the project. The main part of the work was conducted within the earlier safety assessment SR-Can, which was a preparatory stage for the SR-Site assessment. The overall objective of the FEP analysis and processing in both SR-Can and SR-Site included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The primary objective in SR-Site was to establish an SR-Site FEP catalogue within the framework of the SKB FEP database. This FEP catalogue was required to contain all FEPs that needed to be handled in SR-Site and is an update of the corresponding SR-Can FEP catalogue that was established for the SR-Can assessment. The starting point for the handling of FEPs in SR-Site was the SR-Can version of the SKB FEP database and associated SR-Can reports. The SR-Can version of the SKB FEP database includes the SR-Can FEP catalogue, as well as the sources for the identification of FEPs in SR-Can, namely the SR 97 processes and variables, Project FEPs in the NEA International FEP database version 1.2 and matrix interactions in the Interaction matrices developed for a deep repository of the KBS-3 type. Since the completion of the FEP work within SR-Can, an updated electronic version, version 2.1, of the NEA FEP database has become available. Compared with version 1.2 of the NEA FEP database, version 2.1 contains FEPs from two more projects. As part of SR-Site, all new Project FEPs in version 2.1 of the NEA FEP database have been mapped according to the methodology adopted in SR-Can resulting in an SR-Site version of the SKB FEP database. The SKB FEP

  6. FEP report for the safety assessment SR-Site

    International Nuclear Information System (INIS)

    2010-12-01

    This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Site, and forms an important part of the reporting of the project. The main part of the work was conducted within the earlier safety assessment SR-Can, which was a preparatory stage for the SR-Site assessment. The overall objective of the FEP analysis and processing in both SR-Can and SR-Site included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The primary objective in SR-Site was to establish an SR-Site FEP catalogue within the framework of the SKB FEP database. This FEP catalogue was required to contain all FEPs that needed to be handled in SR-Site and is an update of the corresponding SR-Can FEP catalogue that was established for the SR-Can assessment. The starting point for the handling of FEPs in SR-Site was the SR-Can version of the SKB FEP database and associated SR-Can reports. The SR-Can version of the SKB FEP database includes the SR-Can FEP catalogue, as well as the sources for the identification of FEPs in SR-Can, namely the SR 97 processes and variables, Project FEPs in the NEA International FEP database version 1.2 and matrix interactions in the Interaction matrices developed for a deep repository of the KBS-3 type. Since the completion of the FEP work within SR-Can, an updated electronic version, version 2.1, of the NEA FEP database has become available. Compared with version 1.2 of the NEA FEP database, version 2.1 contains FEPs from two more projects. As part of SR-Site, all new Project FEPs in version 2.1 of the NEA FEP database have been mapped according to the methodology adopted in SR-Can resulting in an SR-Site version of the SKB FEP database. The SKB FEP

  7. PENENTUAN LAMA SULFONASI PADA PROSES PRODUKSI SURFAKTAN MES UNTUK APLIKASI EOR

    Directory of Open Access Journals (Sweden)

    Mira Rivai

    2011-04-01

    Full Text Available For producing oil remains that remained at old oil wells (mature field, a method of advanced oil acquirement improvement known as an Enhanced Oil Recovery (EOR should be applied. Surfactant plays an important role in EOR process by reducing interfacial tension (IFT, altering wettability, reducing oil viscosity, and stabilizing dispersion to facilitate the process of oil jetting from reservoir to production well. To optimally cleanse oil that still remained a surfactant compatible with formation water and reservoir is needed. This study was conducted to get the best time of sulfonation process for producing MES surfactant with lower interfacial tension for EOR application. Results showed that the best times of sulfonation process with lower interfacial tension value were 3 and 4 hours

  8. ‘El Mesías’: tradición, religiosidad y magnetismo

    Directory of Open Access Journals (Sweden)

    Marco Antonio De La Ossa Martínez

    2018-01-01

    En defnitiva, en este artículo nos acercaremos a la vida y obra de Haendel, su vinculación con Bach y la génesis y características de El Mesías. Además, incluiremos un poema que Dubosq escribió sobre Haendel, una discografía y flmografía recomendada sobre la obra, el índice de la misma y los textos en inglés y español. Tampoco olvidaremos citar algunas curiosidades, como la relación que le unió dos siglos después con Jimi Hendrix o un nuevo éxito del alemán nacionalizado inglés en el siglo XXI: el himno de la Champions League

  9. Thermal infrared and microwave absorbing properties of SrTiO3/SrFe12O19/polyaniline nanocomposites

    International Nuclear Information System (INIS)

    Hosseini, Seyed Hossein; Zamani, Parisa; Mousavi, S.Y.

    2015-01-01

    Graphical abstract: We have developed a new perspective of applications and properties of conducting polymers. The combination of absorption ability prepared nanocomposites in the present of PANI display a great potential in organization of shielding structures into thermal IR and microwave. Further investigations using other conducting polymers to demonstrate their capability for advance thermal IR and microwave shielding devices is under way. The application of these samples may improve the IR thermographic detection, catalysis, sensors, magnetic data storage, electromagnetic resonance wave absorption, photonic crystals, and microelectronic devices and military aspects. - Highlights: • The SrTiO 3 /SrFe 12 O 19 /PANI exhibited electric and electromagnetic properties. • The SrTiO 3 /SrFe 12 O 19 /PANI has shielding structures into thermal IR and microwave. • Increasing weight ratios and thicknesses will increase thermal IR ability. • Increasing weight ratios and thicknesses will increase microwave absorption ability. - Abstract: Polyaniline (PANI) as a unique polymer that also has electromagnetic absorption used as the substrate. In this research, SrTiO 3 was synthesized as IR absorbent and core and then SrFe 12 O 19 as microwave absorbent was prepared on SrTiO 3 via co-precipitation method as the first shell. As the next step, PANI was coated on SrTiO 3 /SrFe 12 O 19 nanoparticles via in situ polymerization by multi core–shell structures (SrTiO 3 /SrFe 12 O 19 /PANI). Nanometer size and structures of samples were measured by TEM, XRD and FTIR. Morphology of nanocomposite was showed by SEM images. The magnetic and electric properties were also performed by VSM and four probe techniques. Thermal infrared (IR) absorption and microwave reflection loss of nanocomposites were investigated at 10–40 μm and 8–12 GHz, IR and microwave frequencies, respectively. The results showed that the SrTiO 3 /SrFe 12 O 19 /PANI nanocomposites have good compatible

  10. Changes in local surface structure and Sr depletion in Fe-implanted SrTiO{sub 3} (001)

    Energy Technology Data Exchange (ETDEWEB)

    Lobacheva, O., E-mail: olobache@gmail.com [Department of Physics and Astronomy, Western University, London, ON N6A 5B7 (Canada); Yiu, Y.M. [Department of Chemistry, Western University, London, ON N6A 5B7 (Canada); Chen, N. [Canadian Light Source, Saskatoon, SK S7N 0X4 (Canada); Sham, T.K.; Goncharova, L.V. [Department of Physics and Astronomy, Western University, London, ON N6A 5B7 (Canada); Department of Chemistry, Western University, London, ON N6A 5B7 (Canada)

    2017-01-30

    Highlights: • Fe ion implantation of SrTiO{sub 3} and post-implantation results in formation of Sr{sub 1-y}Ti{sub 1-x}Fe{sub x+y}O{sub 3-δ} phase. • In Sr{sub 1-y}Ti{sub 1-x}Fe{sub x+y}O{sub 3-δ} phase, Fe assumes Fe{sup 3+} oxidation state in the bulk and Fe{sup 2+} oxidation state in the near surface area. • FEFF9 calculations indicate that Fe ions can substitute both Ti and Sr sites. • Formation of Sr{sub 1-y}Ti{sub 1-x}Fe{sub x+y}O{sub 3-δ} phase is accompanied by Sr depletion in the near surface region. - Abstract: Local surface structure of single crystal strontium titanate SrTiO{sub 3} (001) samples implanted with Fe in the range of concentrations between 2 × 10{sup 14} to 2 × 10{sup 16} Fe/cm{sup 2} at 30 keV has been investigated. In order to facilitate Fe substitution (doping), implanted samples were annealed in oxygen at 350 °C. Sr depletion was observed from the near-surface layers impacted by the ion-implantation process, as revealed by Rutherford Backscattering Spectrometry (RBS), X-ray photoelectron spectroscopy (XPS), X-ray Absorption Near Edge Spectroscopy (XANES), and Atomic Force Microscopy (AFM). Hydrocarbon contaminations on the surface may contribute to the mechanisms of Sr depletion, which have important implications for Sr(Ti{sub 1-x}Fe{sub x})O{sub 3-δ} materials in gas sensing applications.

  11. New aragonite 87Sr/86Sr records of Mesozoic ammonoids and approach to the problem of N, O, C and Sr isotope cycles in the evolution of the Earth

    Science.gov (United States)

    Zakharov, Yuri D.; Dril, Sergei I.; Shigeta, Yasunari; Popov, Alexander M.; Baraboshkin, Eugenij Y.; Michailova, Irina A.; Safronov, Peter P.

    2018-02-01

    New Sr isotope data from well-preserved aragonite ammonoid shell material from the Mesozoic are compared with that from a living Nautilus shell. The prominent negative Sr isotope excursions known from the Middle Permian, Jurassic and Cretaceous probably have their origins in intensive plate tectonic activity, followed by enhanced hydrothermal activity at the mid-ocean ridges (mantle volcanism) which supplied low radiogenic Sr to seawater. The maximum positive (radiogenic) shift in the lower Mesozoic Sr isotope curve (Lower Triassic peak) was likely caused by a significant expansion of dry land surfaces (Dabie-Sulu Triassic orogeny) and their intensive silicate weathering in conditions of extreme warming and aridity in the very end of the Smithian, followed by warm and humid conditions in the late Spathian, which apparently resulted in a significant oceanic input of radiogenic Sr through riverine flux. The comparatively high 87Sr/86Sr ratio obtained from the living Nautilus shell is probably a function of both the Alpine orogeny, which was accompanied by significant continental weathering and input of radiogenic Sr to the oceans, and the weakening of mantle volcanism.

  12. Over-expression of SR-cyclophilin, an interaction partner of nuclear pinin, releases SR family splicing factors from nuclear speckles

    International Nuclear Information System (INIS)

    Lin, C.-L.; Leu, Steve; Lu, M.-C.; Ouyang Pin

    2004-01-01

    Pre-mRNA splicing takes place within a dynamic ribonucleoprotein particle called the spliceosome and occurs in an ordered pathway. Although it is known that spliceosome consists of five small nuclear RNAs and at least 50 proteins, little is known about how the interaction among the proteins changes during splicing. Here we identify that SR-cyp, a Moca family of nuclear cyclophilin, interacts and colocalizes with nuclear pinin (pnn), a SR-related protein involving in pre-mRNA splicing. Nuclear pnn interacts with SR-cyp via its C-terminal RS domain. Upon SR-cyp over-expression, however, the subnuclear distribution of nuclear pnn is altered, resulting in its redistribution from nuclear speckles to a diffuse nucleoplasmic form. The diffuse subnuclear distribution of nuclear pnn is not due to epitope masking, accelerated protein turnover or post-translational modification. Furthermore, we find that SR-cyp regulates the subnuclear distribution of other SR family proteins, including SC35 and SRm300, in a similar manner as it does on nuclear pnn. This result is significant because it suggests that SR-cyp plays a general role in modulating the distribution pattern of SR-like and SR proteins, similar to that of Clk (cdc2-like kinase)/STY on SR family splicing factors. SR-cyp might direct its effect via either alteration of protein folding/conformation or of protein-protein interaction and thus may add another control level of regulation of SR family proteins and modification of their functions

  13. Dealing with Communicative Problems in English as a Lingua Franca | Traiter les problèmes communicatifs en anglais considéré comme lingua franca

    Directory of Open Access Journals (Sweden)

    Agnieszka Nowicka

    2008-01-01

    Full Text Available De nos jours, l’anglais est l’une des langues les plus utilisées dans la communication internationale. Les locuteurs qui recourent à l’anglais en tant que lingua franca maîtrisent cette langue de façon inégale. Cependant, dans ce type d’échanges les locuteurs ne sont pas confrontés uniquement à des problèmes d’origine linguistique. Notre but, dans le présent article, est de réfléchir, tout d’abord, à la question de comment les différences socio-culturelles, au niveau des styles d’interaction, peuvent influencer la communication. Ensuite, on se focalisera sur les différentes façons dont les locuteurs réagissent aux problèmes de cette nature lorsqu’ils apparaissent dans l’interaction et, finalement, on démontrera comment ces problèmes sont négociés par les locuteurs. Nous recourrons à l’analyse conversationnelle afin d’analyser des extraits d’interactions en anglais qui serviront d’illustration.

  14. PyMEs : Guía de comunicación para exportación

    OpenAIRE

    Barandiain, Dolores; Feiteler, Daniela Elizabeth; Longarzo, María Florencia

    2007-01-01

    Esta guía de comunicación está dirigida al empresario PyME que pretende insertarse en la actividad exportadora o que aspira a mejorar dicho proceso. Este material tiene como objetivo aportar herramientas útiles, prácticas y claras vinculadas a la comunicación, entendiendo el concepto como un valor agregado en la gestión de las PyMEs que exportan. Cualquier acción que la empresa realice va a construir un sentido en el destinatario. A partir de aquí, se plantea la Guía de Comunicación para Expo...

  15. 89Sr and 90Sr in atmospheric precipitations in May 1986 in Bucharest-Magurele area

    International Nuclear Information System (INIS)

    Paunescu, N.; Vata, I.

    1987-08-01

    Sr-89 and Sr-90 were determined in the fallout of May 1986. The maximum values of 335 Bq/(m 2 * 6 hours) and 110 Bq/(m 2 * 6 hours) were observed at May 2 and 5. Throughout May 1986 a quantity of 860 Bq/m 2 of Sr-90 deposited from the fallout in the Bucharest -Magurele area was determined. (authors)

  16. 87Sr/86Sr ratios in hydrothermal waters and deposits from the east pacific rise at 210N

    International Nuclear Information System (INIS)

    Albarede, F.; Michard, A.; Minster, J.F.; Michard, G.

    1981-01-01

    87 Sr/ 86 Sr ratios of three hydrothermal waters collected on the East Pacific Rise at 21 0 N define a mixing line between seawater and a hydrothermal end-member at 0.7030 which is derived by seawater-basalt interaction at ca. 350 0 C and water/rock ratio of about 1.5. Sr concentrations are not affected in the process while Mg uptake from seawater is almost complete. Up to 2/3 of this hydrothermal component is involved in anhydrite precipitation while the Sr isotopic ratio in sulfides (chalcopyrite + sphalerite) cannot be distinguished from that of sulfate. It is estimated that ca. 1 x 10 10 moles of strontium are yearly cycled in the hydrothermal systems of mid-oceanic ridges, thereby affecting the 87 Sr/ 86 Sr budget of seawater. Mass balance between river runoff, limestone precipitation and ridge basalt alteration suggests that the 87 Sr/ 86 Sr ratios of the river runoff are in the range 0.7097-0.7113, and are largely dominated by limestone alteration. (orig.)

  17. Synthetic clay excels in 90Sr removal

    International Nuclear Information System (INIS)

    Komarneni, Sridhar; Kodama, Tatsuya; Paulus, William J.; Carlson, C.

    2000-01-01

    Tests with actual ground water from Hanford site, and fundamental studies of 2Na + →Sr 2+ exchange equilibria revealed that a synthetic clay is extremely selective for 90 Sr with a high capacity for uptake. Comparative studies with existing Sr selective ion exchangers clearly revealed that the present synthetic clay exhibited the best performance for 90 Sr removal from actual ground water collected from three different locations at Hanford. This novel Sr ion sieve is expected to be useful for the decontamination of the environment after accidental release and contamination with 90 Sr. (c) 2000 Materials Research Society

  18. The influence of Sr on the microstructure, degradation and stress corrosion cracking of the Mg alloys - ZK40xSr.

    Science.gov (United States)

    Chen, Lianxi; Bin, Yuanhong; Zou, Wenqi; Wang, Xiaojian; Li, Wei

    2017-02-01

    In the present work, new magnesium (Mg) alloys (Mg-4Zn-0.6Zr-xSr, x=0, 0.4, 0.8, 1.2, 1.6wt%; ZK40xSr) were prepared and studied as potential biodegradable materials. The influence of strontium (Sr) addition on the properties of the new Mg alloys was investigated, which included microstructure, corrosion degradation, and the stress corrosion cracking (SCC) susceptibility. The average grain size of the ZK40Sr was approximately 100µm, which was significantly smaller than that of ZK40 alloy without Sr (402.3±40.2µm). The size of grain boundaries precipitates in the ZK40xSr alloys gradually increased with the increase of Sr content. The grain boundaries finally showed a continuously distribution and net-like shape. The degradation test showed that the average degradation rate of the ZK40xSr alloys increased with the increase of Sr addition. In the case of Mg-4Zn-0.6Zr, the degradation rate was 2.2mgcm -2 day -1 , which was lower than that of Mg-4Zn-0.6Zr-1.6Sr (4.93mgcm -2 day -1 ). When the ZK40xSr alloys were immersed in m-SBF, the rod-like Sr-contained hydroxyapatite (HA) substance was detected, which was known to enhance cell growth around bone implants. The fracture surfaces of the as-cast Mg-4Zn-0.6Zr-1.6Sr were shown intergranular stress corrosion cracking (IGSCC) patterns. The increase of SCC susceptibility of the higher Sr ZK40xSr alloys was attributed to the increase of micro-galvanic corrosion between the α-Mg and the grain boundaries precipitates. The SCC susceptibility values were ≈0.13 and ≈0.41 for the Mg-4Zn-0.6Zr-0.4Sr and the Mg-4Zn-0.6Zr-1.6Sr, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Surface modeling and chemical solution deposition of SrO(SrTiO3)n Ruddlesden-Popper phases

    International Nuclear Information System (INIS)

    Zschornak, M.; Gemming, S.; Gutmann, E.; Weissbach, T.; Stoecker, H.; Leisegang, T.; Riedl, T.; Traenkner, M.; Gemming, T.; Meyer, D.C.

    2010-01-01

    Strontium titanate (STO) is a preferred substrate material for functional oxide growth, whose surface properties can be adjusted through the presence of Ruddlesden-Popper (RP) phases. Here, density functional theory (DFT) is used to model the (1 0 0) and (0 0 1) surfaces of SrO(SrTiO 3 ) n RP phases. Relaxed surface structures, electronic properties and stability relations have been determined. In contrast to pure STO, the near-surface SrO-OSr stacking fault can be employed to control surface roughness by adjusting SrO and TiO 2 surface rumpling, to stabilize SrO termination in an SrO-rich surrounding or to increase the band gap in the case of TiO 2 termination. RP thin films have been epitaxially grown on (0 0 1) STO substrates by chemical solution deposition. In agreement with DFT results, the fraction of particular RP phases n = 1-3 changes with varying heating rate and molar ratio Sr:Ti. This is discussed in terms of bulk formation energy.

  20. Construction of the seawater 87Sr/86Sr curve for the Cenozoic and Cretaceous: supporting data

    International Nuclear Information System (INIS)

    Koepnick, R.B.; Burke, W.H.; Denison, R.E.; Hetherington, E.A.; Nelson, H.F.; Otto, J.B.; Waite, L.E.

    1985-01-01

    We present the data used to construct the Cenozoic and Cretaceous portion of the Phanerozoic curve of seawater 87 Sr/ 86 Sr that had been given in summary form by W.H. Burke and coworkers. All Cenozoic samples (128) and 22 Cretaceous samples are foram-nannofossil oozes and limestones from DSDP cores distributed among 13 sites in the Atlantic, Pacific and Indian Oceans, and the Caribbean Sea. Non-DSDP Cretaceous samples (126) include limestone, anhydrite and phosphate samples from North America, Europe and Asia. Determination of the 87 Sr/ 86 Sr value of seawater at particular times in the past is based on comparison of ratios derived from coeval marine samples from widely separated geographic areas. The general configuration of the Cenozoic and Cretaceous curve appears to be strongly influenced by the history of plate interactions and sea-floor spreading. Specific rises and falls in the 87 Sr/ 86 Sr of seawater, however, may be caused by a variety of factors such as variation in lithologic composition of the crust exposed to weathering, configuration and topographic relief of continents, volcanic activity, rate of sea-floor spreading, extent of continental inundation by epeiric seas, and variations in both climate and paleo-oceanographic conditions. Many or all of these factors are probably related to global tectonic processes, yet their combined effect on the temporal variation of seawater 87 Sr/ 86 Sr can complicate a direct plate-tectonic interpretation for portions of the seawater curve. (Auth.)

  1. A STUDY OF ANTICONVULSANT EFFECT OF FLUNARIZINE AND NIFEDIPINE IN COMPARISON WITH SODIUM VALPROATE ON MES AND PTZ MODELS OF EPILEPSY IN ALBINO RATS

    Directory of Open Access Journals (Sweden)

    Umesh G.

    2015-03-01

    Full Text Available BACKGROUND : CA +2 ions are involved in initiation as well as spread of seizures. Hence current study was undertaken to evaluate the anticonvulsant effect of calcium channel blockers flunarizine, nifedipine and compare their efficacy with that of sodium valproate, the broad spectrum anticonvulsant in MES and PTZ induced seizures in albino rats. MATERIALS AND METHODS : Albino rats were treated with nife dipine 2.5mg/kg, 5mg/kg, flunarizine 7.5mg/kg,15mg/kg and sodium valproate 250mg/kg bodyweight intraperitoneally and the effects were observed in MES and PTZ models of epilepsy. The parameters observed in MES model was , duration of HLTE phase . Convulsive p hase, and post ictal depressive phase. In PTZ model duration of seizure latency, duration of convulsion , and duration post ictal depression were observed. RESULTS : our study demonstrated that both calcium channel blockers afford protection against convulsi ons induced in both models, and flunarizine affords higher degree of protection than nifedipine, with its efficacy almost approaching that of sodium valproate. CONCLUSION : Flunarizine has significant, while nifedipine has moderate degree of anticonvulsant activity as compared to sodium valproate

  2. Enthalpies of formation of Cd0.917Sr0.083, Cd0.857Sr0.143 and Cd0.667Sr0.333 intermetallic compounds

    International Nuclear Information System (INIS)

    Agarwal, Renu; Singh, Ziley

    2008-01-01

    Cadmium is expected to be the solvent for pyrochemical processing of the metallic nuclear fuel. Therefore, thermodynamic properties of cadmium with various fuel and clad elements are of interest. Enthalpies of formation of the intermetallic compounds of Cd-Sr system, Cd 0.917 Sr 0.083 , Cd 0.857 Sr 0.143 and Cd 0.667 Sr 0.333 were determined by precipitation using Calvet calorimeter. Enthalpies of formation of the compounds were found to be -3.05 ± 0.5 kJ mol -1 at 723 K, -14.2 ± 0.7 kJ mol -1 at 843 K and -28.4 ± 0.8 kJ mol -1 at 863 K, respectively. Enthalpies of formation of Cd 0.917 Sr 0.083 and Cd 0.857 Sr 0.143 were also determined by partial enthalpy of formation measurements and the values were found to be -3.9 ± 1.1 kJ mol -1 at 723 K and -13.42 ± 1.2 kJ mol -1 at 843 K, respectively. Miedema model was used to estimate the enthalpies of formation of these compounds and the estimated values were compared with the experimentally determined values

  3. Thermodynamic Modeling of Sr/TRU Removal

    International Nuclear Information System (INIS)

    Felmy, A.R.

    2000-01-01

    This report summarizes the development and application of a thermodynamic modeling capability designed to treat the Envelope C wastes containing organic complexants. A complete description of the model development is presented. In addition, the model was utilized to help gain insight into the chemical processes responsible for the observed levels of Sr, TRU, Fe, and Cr removal from the diluted feed from tank 241-AN-107 which had been treated with Sr and permanganate. Modeling results are presented for Sr, Nd(III)/Eu(III), Fe, Cr, Mn, and the major electrolyte components of the waste (i.e. NO 3 , NO 2 , F,...). On an overall basis the added Sr is predicted to precipitate as SrCO 3 (c) and the MnO 4 - reduced by the NO 2 - and precipitated as a Mn oxide. These effects result in only minor changes to the bulk electrolyte chemistry, specifically, decreases in NO 2 - and CO 3 2- , and increases in NO 3 - and OH - . All of these predictions are in agreement with the experimental observations. The modeling also indicates that the majority of the Sr, TRU's (or Nd(III)/Eu(III)) analogs, and Fe are tied up with the organic complexants. The Sr and permanganate additions are not predicted to effect these chelate complexes significantly owing to the precipitation of insoluble Mn oxides or SrCO 3 . These insoluble phases maintain low dissolved concentrations of Mn and Sr which do not affect any of the other components tied up with the complexants. It appears that the removal of the Fe and TRU'S during the treatment process is most likely as a result of adsorption or occlusion on/into the Mn oxides or SrCO 3 , not as direct displacement from the complexants into precipitates. Recommendations are made for further studies that are needed to help resolve these issues

  4. Using 87Sr/86Sr ratios to investigate changes in stream chemistry during snowmelt in the Provo River, Utah, USA

    Science.gov (United States)

    Hale, C. A.; Carling, G. T.; Fernandez, D. P.; Nelson, S.; Aanderud, Z.; Tingey, D. G.; Dastrup, D.

    2017-12-01

    Water chemistry in mountain streams is variable during spring snowmelt as shallow groundwater flow paths are activated in the watershed, introducing solutes derived from soil water. Sr isotopes and other tracers can be used to differentiate waters that have interacted with soils and dust (shallow groundwater) and bedrock (deep groundwater). To investigate processes controlling water chemistry during snowmelt, we analyzed 87Sr/86Sr ratios, Sr and other trace element concentrations in bulk snowpack, dust, soil, soil water, ephemeral channels, and river water during snowmelt runoff in the upper Provo River watershed in northern Utah, USA, over four years (2014-2017). Strontium concentrations in the river averaged 20 ppb during base flow and decreased to 10 ppb during snowmelt runoff. 87Sr/86Sr ratios were around 0.717 during base flow and decreased to 0.715 in 2014 and 0.713 in 2015 and 2016 during snowmelt, trending towards less radiogenic values of mineral dust inputs in the Uinta Mountain soils. Ephemeral channels, representing shallow flow paths with soil water inputs, had Sr concentrations between 7-20 ppb and 87Sr/86Sr ratios between 0.713-0.716. Snowpack Sr concentrations were generally soils that contain accumulated dust deposits with a less radiogenic 87Sr/86Sr ratio. These results suggest that flow paths and atmospheric dust are important to consider when investigating variable solute loads in mountain streams.

  5. Preparation and crystal structure of SrCu/sub 2/Sb/sub 2/ and SrZnBi/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Cordier, G; Eisenmann, B; Schaefer, H [Technische Hochschule Darmstadt (Germany, F.R.). Fachbereich Anorganische Chemie und Kernchemie

    1976-10-01

    SrCu/sub 2/Sb/sub 2/ and SrZnBi/sub 2/ have been prepared and analytically and structurally characterized. SrCu/sub 2/Sb/sub 2/ crystallizes tetragonal in the CaBe/sub 2/Ge/sub 2/ structure type. SrZnBi/sub 2/ has its own structure type. In both structures the transition metal atoms form with the semimetal atoms tetragonal pyramids, which are connected by common edges of the basis to twodimensional sheets. These sheets are separated in the case of SrCu/sub 2/Sb/sub 2/ by single sheets of strontium atoms, in the case of SrZnBi/sub 2/ by double sheets of strontium atoms in which fourfold nets of Bi atoms are located.

  6. Spectroscopic and electric dipole properties of Sr+Ar and SrAr systems including high excited states

    Science.gov (United States)

    Hamdi, Rafika; Abdessalem, Kawther; Dardouri, Riadh; Al-Ghamdi, Attieh A.; Oujia, Brahim; Gadéa, Florent Xavier

    2018-01-01

    The spectroscopic properties of the fundamental and several excited states of Sr+Ar and SrAr, Van der Waals systems are investigated by employing an ab initio method in a pseudo-potential approach. The potential energy curves and the spectroscopic parameters are displayed for the 1-10 2Σ+, 1-6 2Π and 1-3 2Δ electronic states of the Sr+Ar molecule and for the 1-6 1Σ+, 1-4 3Σ+, 1-3 1,3Π and 1-3 1,3Δ states of the neutral molecule SrAr. In addition, from these curves, the vibrational levels and their energy spacing are deduced for Σ+, Π and Δ symmetries. The spectra of the permanent and transition dipole moments are studied for the 1,3Σ+ states of SrAr, which are considered to be two-electron systems and 2Σ+ states of the single electron Sr+Ar ion. The spectroscopic parameters obtained for each molecular system are compared with previous theoretical and experimental works. A significant correlation revealed the accuracy of our results.

  7. Sr - an element shows the way - Applications of Sr isotopes for provenance, tracing and migration (Invited)

    Science.gov (United States)

    Prohaska, T.; Irrgeher, J.; Zitek, A.; Teschler Nicola, M.

    2010-12-01

    Strontium - named after the small Scottish town Strontian - as such is an element with little popularity. Firstly described by Martin Heinrich Klaproth in 1798, the metal is used in metallurgy to some extent whereas its compounds are interesting in glass industries, electronics and pyrotechnics. The element has chemical similarity to Ca and makes up 1/60 of the earth’s amount of the latter. Nonetheless, it is its isotopic composition which makes Sr so interesting for a large number of scientists. The natural composition of the four naturally occurring isotopes (84Sr, 86Sr 87Sr and 88Sr) varies in nature due to the radioactive decay of 87Rb to 87Sr. Thus, it was early recognized as geochronometer especially in Ca rich matrices. With increasing precision of applied methodology, the natural variation of the 87Sr/86Sr isotope ratio (analyzed at first mainly by thermal ionization mass spectrometry (TIMS)) became more and more popular in provenance studies. The natural variation of the ratio is mainly determined by the geological age and the original composition of the rock and can be used therefore as fingerprint of the local geology. The ratio is transferred with no significant fractionation via the water into plants and finally via the food chain into animal and human tissues (especially bones and teeth). As the element is chemically similar to Ca, it appears in most matrices. The use for provenance studies is supported by the fact that the long half life (4.8 x 1010 years) does not lead to an alteration during the time scales which are investigated (from recent samples to human or animal skeletal remains which date back up to 30.000 BC). The uniqueness of the system besides the natural variation is defined by the ubiquity in nature and the relatively high (and thus measurable) elemental concentration in most tissues. It was finally the advent of multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) which augmented the number of applications

  8. Epitaxial growth and thermodynamic stability of SrIrO3/SrTiO3 heterostructures

    Science.gov (United States)

    Groenendijk, D. J.; Manca, N.; Mattoni, G.; Kootstra, L.; Gariglio, S.; Huang, Y.; van Heumen, E.; Caviglia, A. D.

    2016-07-01

    Obtaining high-quality thin films of 5d transition metal oxides is essential to explore the exotic semimetallic and topological phases predicted to arise from the combination of strong electron correlations and spin-orbit coupling. Here, we show that the transport properties of SrIrO3 thin films, grown by pulsed laser deposition, can be optimized by considering the effect of laser-induced modification of the SrIrO3 target surface. We further demonstrate that bare SrIrO3 thin films are subject to degradation in air and are highly sensitive to lithographic processing. A crystalline SrTiO3 cap layer deposited in-situ is effective in preserving the film quality, allowing us to measure metallic transport behavior in films with thicknesses down to 4 unit cells. In addition, the SrTiO3 encapsulation enables the fabrication of devices such as Hall bars without altering the film properties, allowing precise (magneto)transport measurements on micro- and nanoscale devices.

  9. Non-Financial Performance Measurement for Shariah Banks : a Survey to Masyarakat Ekonomi Syariah (MES) Surakarta

    OpenAIRE

    Astuti, Septin Puji; Astika, Hari

    2011-01-01

    Measurement of non-financial performance in shariah banks is needed to enhance their market share and to maintain their long-term sustainability. The main aim of this research is to show the position of shariah banks in Surakarta in respect with their non-financial aspects (i.e. product, service, human resource and image) based on opinions given by members of Shariah Economic Society (MES) of Surakarta. Extent analysis for Fuzzy Analytic Hierarchy Process is employed to measure the non-financ...

  10. Comment les aires protégées structurent les écosystèmes des ...

    African Journals Online (AJOL)

    1 mars 2009 ... Cette étude menée a pour but de montrer l'influence des aires protégées sur la structuration des écosystèmes périphériques. Pour cela, une étude diachronique par images satellitaires Landsat de 1985 à 2013 a été faite et une collecte de données de terrain a été réalisée dans les villages autour du Parc ...

  11. 87Sr/86Sr ratios in permo-carboniferous sea water from the analyses of well-preserved brachiopod shells

    International Nuclear Information System (INIS)

    Popp, B.N.; Anderson, T.F.

    1986-01-01

    Sr isotopic analyses of well-preserved portions of Permo-Carboniferous brachiopods distributed globally confirm the general shape of the Sr isotope age curve established by previous workers for this time interval. There is little variation between the SR isotopic composition of unaltered portions of brachiopods and that of portions of the same shell interpreted to be diagenetically altered (based on cathodoluminescence, elemental, and stable isotopic data). However, the Sr isotopic composition in diagenetically altered micritic matrix adjacent to the shell is more radiogenic. The Sr isotopic composition in the unaltered portions of calcitic megafossils has potential as a stratigraphic tool. (author)

  12. Review of SR 97 performance assessment

    International Nuclear Information System (INIS)

    Glynn, P.D.

    2000-01-01

    This review has identified many technical problems in the SR 97 performance assessment. The general impression of this reviewer is that SKB has been disingenuous in its performance assessment effort. It has not cited important differences of opinion with its own views. Furthermore, there are many inconsistencies in the SR 97 report that all together leave the impression that there are many more uncertainties in the SR 97 performance assessment than SKB would perhaps care to admit. Additionally, despite SKB's statements to the contrary, many of the analyses conducted for the SR 97 performance assessment can be clearly shown not to have been based on 'conservative' assumptions. Finally, SKB has made little effort to consider possible coupling effects between their different scenarios in SR 97. This is a serious flaw in the SR 97 performance assessment. The comments in this review should not be taken to imply that the KBS-3 nuclear waste disposal method will not be able to meet the safety and radiation protection requirements which SKI and SSI have specified in recent years. Instead, my conclusion is simply that the SR 97 performance assessment of the KBS-3 method would have been more believable had it been based on a forthright and comprehensive discussion of facts, uncertainties and opinions, and on a more conservative choice of assumptions. As it stands, the SR 97 performance assessment is not very credible

  13. 87Sr/86Sr isotopes in grapes of different cultivars: A geochemical tool for geographic traceability of agriculture products.

    Science.gov (United States)

    Tescione, Ines; Marchionni, Sara; Casalini, Martina; Vignozzi, Nadia; Mattei, Massimo; Conticelli, Sandro

    2018-08-30

    87 Sr/ 86 Sr was determined on fresh red and white grapes, soils and rocks from three selected vineyards to verify the isotopic relationships between the fruit of the vine and geologic substrata of vineyards. 87 Sr/ 86 Sr were determined on sampled grapes of four different harvest years and different grape varieties, on bioavailable fraction of soils, on whole soils, and on bedrocks from the geo-pedological substratum of the vineyards. The vineyards chosen for the experimental works belong to an organic farming winery and thus cultivation procedures were strictly controlled. Grapes were sampled during the harvests of four different but consecutive years with 87 Sr/ 86 Sr that does not change reflecting the values of the soil bioavailable fraction. No variations among grapes from different vine cultivars were observed. A strict isotope relationship with soil bio-available fraction was observed. These findings demonstrate the reliability of 87 Sr/ 86 Sr, even at a very small scale, for food products geographic origin assessment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Development of 87Sr/86Sr maps as targeted strategy to support wine quality.

    Science.gov (United States)

    Durante, Caterina; Bertacchini, Lucia; Cocchi, Marina; Manzini, Daniela; Marchetti, Andrea; Rossi, Maria Cecilia; Sighinolfi, Simona; Tassi, Lorenzo

    2018-07-30

    This study summarizes the results obtained from a systematic and long-term project aimed at the development of tools to assess the provenance of food in the oenological sector. In particular, 87 Sr/ 86 Sr isotope ratios were measured on statistically representative set of soils, vine branches and wines sampled in the production district of Modena, worldwide known for the Lambrusco wines production. The obtained data were used to build strontium isotopic maps able to objectively support the Lambrusco PDO wines origin as well as other products of the Modena district. Finally, a strong relationship was found between the 87 Sr/ 86 Sr isotope ratios of soils and vine branches on a large scale, highlighting and confirming once more the idea that plants can also represent an optimal sampling device to support geographical traceability. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Silvio Pellico, Mes prisons : un “best-seller” de l'édification

    Directory of Open Access Journals (Sweden)

    Jean-Claude Vimont

    2012-06-01

    Full Text Available La France réserva un accueil enthousiaste à la traduction du récit de Silvio Pellico (1789-1854, Le mie prigioni. Les mémoires romantiques de ce « martyr de la liberté » italien, incarcéré pendant dix années sous les Plombs de Venise et dans la geôle autrichienne du Spielberg, furent réédités plus de cent cinquante fois en langue française de 1833 à 1914 . Nous cumulons pour atteindre ce chiffre, les traductions de Mes prisons, les traductions augmentées de chapitres inédits, les traductions...

  16. Review of SR 97

    International Nuclear Information System (INIS)

    Voss, C.I.

    2000-01-01

    The safety analysis conducted by SKB for SR 97 is impressive in terms of both scale and content. In addition to an eventual solution to Sweden's nuclear waste isolation question, much general scientific knowledge of real value in other applications will be created as a by-product of SKB's efforts. This review focuses on those geoscience aspects of SR 97 that have the most important effects on radionuclide release from each barrier. Indeed, SR 97 elucidates the most important geoscience parameters that control releases from the near field and the far field; these comprise mainly the transport resistance parameter, and the sorption coefficients for each nuclide, the matrix diffusion coefficient, and the Darcy flux. The Main Report is the most important document in SR 97 inasmuch as it is the only one that brings together all of the supporting work to answer the question of safety. Unfortunately pervading the good supporting work done is the impression that the Main Report is not balanced, that it emphasizes optimistic aspects and downplays the negative. SKB specifies 3 main requirements to guarantee proper repository function: a non-oxidizing subsurface environment, temperatures less than 100 C, and a mechanically stable low-permeability buffer surrounding the canisters. The first and third requirements are not thoroughly proven by SKB. One source of near-field doubt stems from the consequences of combinations of scenarios in which several negative events are linked, while the effect of each scenario is mainly evaluated only independently in SR 97. More pertinently, disastrous breakdown of complex systems may occur due to a chain of linked failures. For example, in the glacial scenario: high ground-water flow (possible ablation of buffer and high fluid transport), change in ground-water chemistry (even the possibility of oxidizing conditions), new flow paths, significant changes in mechanical stress and possible motion along faults (which may also generate new flow

  17. Preparation of Sr adsorptive fiber by impregnating with crown ether derivative for 90Sr measurement

    International Nuclear Information System (INIS)

    Horita, Takuma; Asai, Shiho; Hanzawa, Yukiko; Kitatsuji, Yoshihiro; Konda, Miki; Saito, Kyoichi; Fujiwara, Kunio; Sugo, Takanobu

    2017-01-01

    A Sr adsorption fiber was prepared for rapid analysis of 90 Sr content in the fiber using radiation-induced emulsion graft polymerization and subsequent chemical modification. A polyethylene fiber with a diameter of 13 μm was first immersed in a methanol solution of an epoxy-group-containing vinyl monomer, glycidyl methacrylate (GMA), and polyoxyethylene sorbitol ester (Tween20) as a surfactant for the graft-polymerization of GMA. Octadecylamine was then bound to a polymer chain extending from the fiber surface, providing hydrophobicity to the polymer chain. Dicyclohexano-18-crown-6 (DCH18C6) was finally impregnated onto the polymer chain via a hydrophobic interaction between the octadecyl moiety of the polymer chain and the cyclohexyl moiety of DCH18C6. The fiber surface structure, characterized by DCH18C6 molecules loosely entangled with polymer chains, allowed for the rapid adsorption of Sr ions at an adsorption rate of approximately 100-times higher than that of a commercially available Sr-selective resin (Sr Resin ® ). (author)

  18. Preparation of 90Sr-90Y generator

    International Nuclear Information System (INIS)

    Jin Xiaohai; Yu Haibin; Zhang Jinming; Zhang Peixin; Lin Qiongfang

    1990-01-01

    In recent years, 90 Y has been considered as one of the best radionuclides for tumor radioimmunotherapy when chelated to tumor-associated antibodies. This evaluation is based on the superior properties of this radionuclide (suitable half-life, pure β-ray emitter of intermediate energy, stable daughters, and suitable chemical properties) and because it is available as a radionuclide generator product by decay of its 28a parent 90 Sr. The experimental conditions of 90 Sr- 90 Y generator are described. The elution efficiency of 90 Sr- 90 Y generator reaches 98%. One of the most important problems is the 90 Sr contamination breakthrough from the generator. The level of 90 Sr contamination must be controlled to the clinical standard. The cation exchange resin 732 (100-150 mesh) was successfully used for the separation of 90 Y from 90 Sr. The method used by the authors provides a 90 Y-HAc solution which is very simple and safe for administration to the patients. 90 Y was separated from 90 Sr almost completely, the level of the 90 Sr contamination per 740 MBq 90 Y product was only 0.74 kBq. However the toxicity of 90 Sr is extremely high, the human life-time permissible dose is 74 kBq, then 740 MBq of 90 Y is allowed to be administrated to a patient for 50-100 times

  19. 90Sr- 90Y and 89Sr beta radioactivity measurement in milk samples using a proportional counter

    International Nuclear Information System (INIS)

    Mananes, A.; Perez Santos, C.; Martinez Churiaque, F.

    1987-01-01

    A thin window glas flow proportional counter is used to measure the 90 Sr- 90 Y and 89 Sr beta radioactivity in milk samples. A chemical procedure is used to separate strontium-yttrium from the other radionuclides present in milk. A calculation of the total efficiency of the system is performed which includes an empirical estimation of the backscattering factor. The calibration of the whole process allows the determination of the 90 Sr activity within 10% relative error in spite of uncertainties in the recovery yields of strontium and yttrium. No 89 Sr activity has been detected, and the mean value obtained for the 90 Sr activity in nine milk samples of Cantabria is 0.115 Bq/1 with a minimum detectable activity of 0.0105 Bq. (author) 18 refs

  20. Consideraciones sobre la normativa aplicable en la preparación de información contable de PyMEs

    OpenAIRE

    Rondi, Gustavo R.; Galante, Marcelo Javier

    2012-01-01

    El propósito de la investigación es analizar la situación actual y el impacto futuro de las normas para la preparación de información financiera en las PyMEs en Argentina, a efectos de realizar propuestas específicas y aportar herramientas que contribuyan en la implementación de las mismas.

  1. Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO3)n films by means of metalorganic aerosol deposition

    International Nuclear Information System (INIS)

    Jungbauer, M.; Hühn, S.; Moshnyaga, V.; Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.

    2014-01-01

    We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO 3 ) n (n = ∞, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO 3 (001) substrates by means of a sequential deposition of Sr-O/Ti-O 2 atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2–4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5–6 repetitions of the SrO(SrTiO 3 ) 4 block at the level of 2.4%. This identifies the SrTiO 3 substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy

  2. Activité antérieure – Améliorer la recherche sur les systèmes de ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    15 avr. 2016 ... M. Félix Boa Yapo, directeur général de la santé de la Côte d'Ivoire, a ouvert la séance de consultation, en compagnie de Stanislas Kambour, directeur des systèmes de recherche et de renseignements sur la santé de l'OOAS, et de Chantal de Varennes, ambassadrice du Canada auprès de la République ...

  3. Estudio de marcadores de transición epitelio-mesénquima en neoplasias renales

    OpenAIRE

    Cadenas González, Nuria

    2016-01-01

    HIPÓTESIS: La expresión de ciertas proteínas, ligadas a eventos de transición epitelio-mesénquima en el cáncer renal, podrían estar relacionada con la agresividad biológica y comportarse como marcadores pronósticos. MATERIAL Y MÉTODOS: La población de estudio son 156 pacientes con cáncer renal de las cinco variedades histológicas más frecuentes: carcinoma de células claras (con el subtipo sarcomatoide), carcinoma papilar, carcinoma cromófobo y oncocitoma. El periodo mínimo de seguimiento s...

  4. Peculiarities of Sr-90 migration in the environment

    International Nuclear Information System (INIS)

    Romanov, G.N.; Stukin, D.A.; Aleksakhin, R.M.

    1991-01-01

    The Eastern Urals radioactive track which formed as a result of the Kyshtym accident constituted a natural experimental base for studying the dynamics of Sr-90 behaviour and migration in the environment. Sr-90 behaviour in soil depends on the processes involved in its physical migration horizontally (water runoff, wind transport) and vertically (effective diffusion), on the intensity with which the physico-chemical forms of strontium change, and primarily on Sr-90 incorporation into the soil-absorptive complex. Over 30 years the effective diffusion processes led to downward displacement of Sr-90 in undisturbed soil to a depth of 30 to 50 cm. In 1988 84-94% of the Sr-90 was located in the 10 cm layer as against 90% in the 2 cm layer in the initial 1 or 2 years. The amount of Sr-90 in mobile forms in leached chernozem and grey forest soil hardly changed over time, amounting to between 76 and 90%. In the first 5-10 years Sr-90 surface water runoff was about 0.2% (and Sr-90 wind resuspension 0.1-1.0%) per year of the Sr-90 inventory per unit area. Due to Sr-90 loss from the top soil layer the water runoff and wind resuspension processes decreased exponentially, halving every 4 to 5 years. In most cases, Sr-90 transfer from soil to plants via the roots does not involve discrimination of Sr-90 with regard to calcium, and therefore the Sr-90 accumulation level in various species of natural and agricultural plants depends on their calcium requirements and the amount of exchangeable calcium in the soil. This made it possible to work out quantitative indices for forecasting Sr-90 accumulation in various species of plants for given types of soil. As Sr-90 moves through the trophic chains (including the agricultural one) we find - depending on whether two adjoining links discriminate against it or not as regards calcium - that some organisms reject it while others concentrate it. When restoring farming on the contaminated territory the fact that cattle discriminated against Sr

  5. Applicability of 87Sr/86Sr in examining return flow of irrigation water in highly agricultural watersheds in Japan

    Science.gov (United States)

    Yoshida, T.; Nakano, T.; Shin, K. C.; Tsuchihara, T.; Miyazu, S.; Kubota, T.

    2017-12-01

    Water flows in watersheds containing extensive areas of irrigated paddies are complex because of the substantial volumes involved and the repeated cycles of water diversion from, and return to, streams. For better management of low-flow conditions, numerous studies have attempted to quantify the return flow using the stable isotopes of water; however, the temporal variation in these isotopic compositions due to fractionation during evaporation from water surfaces hinders their application to watersheds with extensive irrigated paddies. In this study, we tested the applicability of the strontium isotopes (87Sr/86Sr, hereafter Sr ratio) for studying hydrological processes in a typical agricultural watershed located on the alluvial fan of the Kinu River, namely the Gogyo River, in central Japan. The Sr ratio of water changes only because of interactions with the porous media it flows through, or because of mixing with water that has different Sr ratios. We sampled water both at a single rice paddy, and on the watershed scale in the irrigated and non-irrigated periods. The soil water under the paddy decreased as sampling depth increased, and the soil water at a depth of 1.5 m showed a similar Sr ratio to the spring. The water sampled in the drainage channel with a concrete lined bottom showed a similar Sr ratio to the irrigation water, whereas that with a soil bottom was plotted between the plots of the irrigation water and shallow aquifer. These results suggest the Sr ratio decreases as it mixes with the soil water through percolation; whereas the Sr ratio will be less likely to change when water drains from paddies via surface pathways. The streamflow samples were plotted linearly on the Sr ratio and 1/Sr plot, indicating that the streamflow was composed of two end-members; the irrigation water and the shallow aquifer. The continuous decline in the Sr ratio along the stream suggests an exfiltration of water from the shallow aquifers. The stream water during the non

  6. Volumetric properties of MES, MOPS, MOPSO, and MOBS in water and in aqueous electrolyte solutions

    International Nuclear Information System (INIS)

    Taha, Mohamed; Lee, Ming-Jer

    2010-01-01

    4-Morpholineethanesulfonic acid (MES), 4-morpholinepropanesulfonic acid (MOPS), 3-morpholino-2-hydroxypropanesulfonic acid (MOPSO), and 4-(N-morpholino)butanesulfonic acid (MOBS), are useful for pH control as standard buffers in the physiological region of 5.5-6.7 for MES, 6.5-7.9 for MOPS, 6.2-7.6 for MOPSO, and 6.9-8.3 for MOBS, respectively. On the basis of density measurements at 298.15 K, the apparent molar volumes, V φ , of the above-mentioned buffers in water and in (0.05, 0.16, and 0.25) mol kg -1 aqueous solutions of NaCl, KCl, KBr, and CH 3 COOK have been calculated. The partial molar volumes at infinite dilution, V φ o , obtained from V φ , have been used to calculate the volume of transfer, Δ tr V φ o , from water to aqueous electrolyte solutions. It was found that both V φ o and Δ tr V φ o vary linearly with increasing the number of carbon atoms in the alkyl group side chain of the zwitterionic buffers. These linear correlations have been utilized to estimate the contributions of the zwitterionic end group (morpholinium ion, -SO 3 - ) and -CH 2 - group to V φ o and Δ tr V φ o . The values of V φ o and Δ tr V φ o for some functional group contributions of the zwittierionic buffers with salts have also been reported.

  7. L'interdépendance entre les sous-systèmes conjugal et parental: une analyse personne-processus-contexte

    Directory of Open Access Journals (Sweden)

    Bigras Marc

    2000-01-01

    Full Text Available Dans le présent article nous étudions les mécanismes de transmission des difficultés socioaffectives entre les systèmes conjugal et parental sous l'effet d'une part de stress contextuels comme la pauvreté des familles et, d'autre part, des caractéristiques personnelles des membres de ces familles comme le sexe et l'âge de l'enfant. Un échantillon de couples avec ou sans enfant permet dans une première étude d'estimer l'impact de la présence de l'enfant sur le couple alors que deux autres études posent la question complémentaire de l'impact du couple sur l'enfant. Les résultats de ces études contribuent à démontrer l'interdépendance entre le couple et l'enfant alors que chaque membre de la famille peut-être une source d'influence sur les autres. Nous argumentons qu'une réponse aversive à des problèmes extrafamiliaux favorise des stress intrafamiliaux mais que cela se révèle surtout selon les caractéristiques des membres de la famille.

  8. Preparation and characterization of Sr-Ti-hardystonite (Sr-Ti-HT nanocomposite for bone repair application

    Directory of Open Access Journals (Sweden)

    Hossein Mohammadi

    2015-07-01

    Full Text Available Objective(s: Hardystonite (HT is Zn-modified silicate bioceramics with promising results for bone tissue regeneration. However, HT possesses no obvious apatite formation. Thus, in this study we incorporated Sr and Ti into HT to prepare Sr-Ti-hardystonite (Sr-Ti-HT nanocomposite and evaluated its in vitro bioactivity with the purpose of developing a more bioactive bone substitute material. Materials and methods:The HT and Sr-Ti-HT were prepared by mechanical milling and subsequent heat treatment. Calcium oxide (CaO, zinc oxide (ZnO and silicon dioxide (SiO2 (all from Merck were mixed with molar ratio of 2:1:2. The mixture of powders mixture was then milled in a planetary ball mill for 20 h. In the milling run, the ball-to-powder weight ratio was 10:1 and the rotational speed was 200 rpm. After synthesis of HT, 3% nanotitanium dioxide (TiO2, Degussa and 3% strontium carbonate (SrCO3, Merck were added to HT and then the mixture was ball milled and calcined at 1150°C for 6 h. Simultaneous thermal analysis (STA, X-ray diffraction (XRD, Transmission electron microscopy (TEM and Fourier transform infra-red spectroscopy (FT-IR performed to characterize the powders. Results:XRD and FT-IR confirmed the crystal phase and silicate structure of HT and TEM images demonstrated the nanostructure of powders. Further, Sr-Ti-HT induced apatite formation and showed a higher human mesenchymal stem cell (hMSCs adhesion and proliferation compared to HT. Conclusion:Our study revealed that Sr-Ti-HT with a nanostructured crystal structure of 50 nm, can be prepared by mechanical activation to use as biomaterials for orthopedic applications.

  9. The influence of Sr content in calcium phosphate coatings

    International Nuclear Information System (INIS)

    Lindahl, Carl; Pujari-Palmer, Shiuli; Hoess, Andreas; Ott, Marjam; Engqvist, Håkan; Xia, Wei

    2015-01-01

    In this study calcium phosphate coatings with different amounts of strontium (Sr) were prepared using a biomineralization method. The incorporation of Sr changed the composition and morphology of coatings from plate-like to sphere-like morphology. Dissolution testing indicated that the solubility of the coatings increased with increased Sr concentration. Evaluation of extracts (with Sr concentrations ranging from 0 to 2.37 μg/mL) from the HA, 0.06Sr, 0.6Sr, and 1.2Sr coatings during in vitro cell cultures showed that Sr incorporation into coatings significantly enhanced the ALP activity in comparison to cells treated with control and HA eluted media. These findings show that calcium phosphate coatings could promote osteogenic differentiation even in a low amount of strontium. - Highlights: • Calcium phosphate coating doping with low Sr contents was prepared via a biomineralization process. • The solubility of the coatings increased with increased Sr concentration. • Present findings show the potential that Sr has on promoting osteogenic differentiation even in a low amount

  10. Metastable equilibrium solubility behavior of carbonated apatite in the presence of solution strontium.

    Science.gov (United States)

    Heslop, D D; Bi, Y; Baig, A A; Higuchi, W I

    2004-01-01

    The purpose of this study was to use the concept of metastable equilibrium solubility (MES) to describe the anomalous solubility behavior of carbonated apatite (CAP) in the presence of solution strontium. A CAP sample (4.8 wt% CO(3), synthesized at 70 degrees C) was prepared by precipitation. Baseline MES distributions were determined in a series of 0.1 M acetate buffers containing only calcium and phosphate (no strontium) over a broad range of solution conditions. In order to assess the influence of strontium, MES profiles were then determined in a similar fashion with 20, 30, 40, 50, 60, 70, and 80% of the solution calcium being replaced on an equal molar basis by solution strontium. From the compositions of the equilibrating buffer solutions, ion activity products (IAPs) of the form Ca(10-n)Sr(n)(PO(4))(6)(OH)(2) (n = 0-10) were calculated in an attempt to determine the correct function governing the dissolution of the CAP preparation. The results demonstrate the following important findings: (a) at high solution strontium/calcium ratios (i.e., when 60% or more of the solution calcium was replaced by strontium), the MES profiles in all the experiments were found to be essentially superimposable when the solution IAPs were calculated using the stoichiometry of Ca(6)Sr(4)(PO(4))(6)(OH)(2), and (b), at low solution strontium/calcium ratios (i.e., when 40% or less of the solution calcium was replaced by strontium), the stoichiometry yielding MES data superpositioning was found to be that of hydroxyapatite. When other stoichiometries were assumed, good superpositioning of the data was not possible.

  11. The inverse F-BAR domain protein srGAP2 acts through srGAP3 to modulate neuronal differentiation and neurite outgrowth of mouse neuroblastoma cells.

    Directory of Open Access Journals (Sweden)

    Yue Ma

    Full Text Available The inverse F-BAR (IF-BAR domain proteins srGAP1, srGAP2 and srGAP3 are implicated in neuronal development and may be linked to mental retardation, schizophrenia and seizure. A partially overlapping expression pattern and highly similar protein structures indicate a functional redundancy of srGAPs in neuronal development. Our previous study suggests that srGAP3 negatively regulates neuronal differentiation in a Rac1-dependent manner in mouse Neuro2a cells. Here we show that exogenously expressed srGAP1 and srGAP2 are sufficient to inhibit valporic acid (VPA-induced neurite initiation and growth in the mouse Neuro2a cells. While ectopic- or over-expression of RhoGAP-defective mutants, srGAP1(R542A and srGAP2(R527A exert a visible inhibitory effect on neuronal differentiation. Unexpectedly, knockdown of endogenous srGAP2 fails to facilitate the neuronal differentiation induced by VPA, but promotes neurite outgrowth of differentiated cells. All three IF-BAR domains from srGAP1-3 can induce filopodia formation in Neuro2a, but the isolated IF-BAR domain from srGAP2, not from srGAP1 and srGAP3, can promote VPA-induced neurite initiation and neuronal differentiation. We identify biochemical and functional interactions of the three srGAPs family members. We propose that srGAP3-Rac1 signaling may be required for the effect of srGAP1 and srGAP2 on attenuating neuronal differentiation. Furthermore, inhibition of Slit-Robo interaction can phenocopy a loss-of-function of srGAP3, indicating that srGAP3 may be dedicated to the Slit-Robo pathway. Our results demonstrate the interplay between srGAP1, srGAP2 and srGAP3 regulates neuronal differentiation and neurite outgrowth. These findings may provide us new insights into the possible roles of srGAPs in neuronal development and a potential mechanism for neurodevelopmental diseases.

  12. Mapping and characterization of wheat stem rust resistance genes SrTm5 and Sr60 from Triticum monococcum.

    Science.gov (United States)

    Chen, Shisheng; Guo, Yan; Briggs, Jordan; Dubach, Felix; Chao, Shiaoman; Zhang, Wenjun; Rouse, Matthew N; Dubcovsky, Jorge

    2018-03-01

    The new stem rust resistance gene Sr60 was fine-mapped to the distal region of chromosome arm 5A m S, and the TTKSK-effective gene SrTm5 could be a new allele of Sr22. The emergence and spread of new virulent races of the wheat stem rust pathogen (Puccinia graminis f. sp. tritici; Pgt), including the Ug99 race group, is a serious threat to global wheat production. In this study, we mapped and characterized two stem rust resistance genes from diploid wheat Triticum monococcum accession PI 306540. We mapped SrTm5, a previously postulated gene effective to Ug99, on chromosome arm 7A m L, completely linked to Sr22. SrTm5 displayed a different race specificity compared to Sr22 indicating that they are distinct. Sequencing of the Sr22 homolog in PI 306540 revealed a novel haplotype. Characterization of the segregating populations with Pgt race QFCSC revealed an additional resistance gene on chromosome arm 5A m S that was assigned the official name Sr60. This gene was also effective against races QTHJC and SCCSC but not against TTKSK (a Ug99 group race). Using two large mapping populations (4046 gametes), we mapped Sr60 within a 0.44 cM interval flanked by sequenced-based markers GH724575 and CJ942731. These two markers delimit a 54.6-kb region in Brachypodium distachyon chromosome 4 and a 430-kb region in the Chinese Spring reference genome. Both regions include a leucine-rich repeat protein kinase (LRRK123.1) that represents a potential candidate gene. Three CC-NBS-LRR genes were found in the colinear Brachypodium region but not in the wheat genome. We are currently developing a Bacterial Artificial Chromosome library of PI 306540 to determine which of these candidate genes are present in the T. monococcum genome and to complete the cloning of Sr60.

  13. Chernobyl 90Sr in bilberries from Poland

    International Nuclear Information System (INIS)

    Mietelski, J.W.; Vajda, N.

    1997-01-01

    As part of a detailed survey on the contamination of Polish forests 90 Sr activity concentrations were determined in bilberries. Elevated 90 Sr levels were found in several samples from north-eastern Poland. The calculated maximum 90 Sr surface contamination was 2 kBq*m -2 . The correlation between 90 Sr and 137 Cs concentrations in bilberries was good for two sets of samples originating from two geographical areas of Poland indicating the local differences in radionuclide depositions from Chernobyl fallout. (author)

  14. Modification of Sr on 4004 Aluminum Alloy

    Science.gov (United States)

    Guo, Erjun; Cao, Guojian; Feng, Yicheng; Wang, Liping; Wang, Guojun; Lv, Xinyu

    2013-05-01

    As a brazing foil, 4004 Al alloy has good welding performance. However, the high Si content decreases the plasticity of the alloy. To improve the plasticity of 4004 Al alloy and subsequently improve the productivity of 4004 Al foil or 434 composite foil, 4004 Al alloy was modified by Al-10%Sr master alloy. Modification effects of an additional amount of Sr, modification temperature, and holding time on 4004 aluminum alloy were studied by orthogonal design. The results showed that the greatest impact parameter of 4004 aluminum alloy modification was the additional amount of Sr, followed by holding time and modification temperature. The optimum modification parameters obtained by orthogonal design were as follows: Sr addition of 0.04%, holding time of 60 min, and modification temperature of 760°C. The effect of Sr addition on modification was analyzed in detail based on orthogonal results. With increasing of Sr addition, elongation of 4004 alloy increased at first, and decreased after reaching the maximum value.

  15. Losses of Sr/sup 90/, Sr/sup 89/, and I/sup 131/ from fallout-contaminated plants

    Energy Technology Data Exchange (ETDEWEB)

    Martin, W E

    1964-11-01

    During the early period following local fallout, and during periods of maximal worldwide fallout, the entry of radionuclides into terrestrial food-chains is due primarily to the external contamination of plants and secondarily to the uptake of radionuclides from contaminated soil. Studies were undertaken to estimate the rates of radionuclide loss from fallout-contaminated vegetation and hence from the diets of herbivores living in a fallout field. On the fifth, fifteenth, thirtieth, and sixtieth days after an underground nuclear explosion (Operation Sedan) at the Nevada Test Site, plant samples were collected from twenty representative locations in the fallout field and analyzed to determined the concentrations (pc/g dry wt) of /sup 90/Sr, /sup 89/Sr, and /sup 131/I at the times of collections. While the radioactive half lives of /sup 90/Sr, /sup 89/Sr, and /sup 131/I are approximately 27.7 years, 53 days, and 8.04 days respectively, their average effective half-lives on fallout-contaminated plants, during the period from 5 to 30 days after the detonation, were 27.8 days, 17.8 days, and 5.0 days respectively. Losses of /sup 90/Sr were attributed to radioactive decay and to the removal of fallout particles and foliage by wind and/or other mechanical disturbances. Losses of /sup 90/Sr and /sup 89/Sr were attributed to radioactive decay and to the removal of fallout particles and foliage by wind and/or other mechanical disturbances. Losses of /sup 131/I were attributed to radioactive decay, to mechanical disturbance, and to the vaporization of /sup 131/I from the fallout particles retained on foliage.

  16. Experimental evidence shows no fractionation of strontium isotopes ((87)Sr/(86)Sr) among soil, plants, and herbivores: implications for tracking wildlife and forensic science.

    Science.gov (United States)

    Flockhart, D T Tyler; Kyser, T Kurt; Chipley, Don; Miller, Nathan G; Norris, D Ryan

    2015-01-01

    Strontium isotopes ((87)Sr/(86)Sr) can be useful biological markers for a wide range of forensic science applications, including wildlife tracking. However, one of the main advantages of using (87)Sr/(86)Sr values, that there is no fractionation from geological bedrock sources through the food web, also happens to be a critical assumption that has never been tested experimentally. We test this assumption by measuring (87)Sr/(86)Sr values across three trophic levels in a controlled greenhouse experiment. Adult monarch butterflies were raised on obligate larval host milkweed plants that were, in turn, grown on seven different soil types collected across Canada. We found no significant differences between (87)Sr/(86)Sr values in leachable Sr from soil minerals, organic soil, milkweed leaves, and monarch butterfly wings. Our results suggest that strontium isoscapes developed from (87)Sr/(86)Sr values in bedrock or soil may serve as a reliable biological marker in forensic science for a range of taxa and across large geographic areas.

  17. Real-time {sup 90}Sr Counter

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, Naomi; Kawai, Hideyuki; Kodama, Satoshi; Kobayashi, Atsushi; Tabata, Makoto; Ito, Hiroshi [Graduate School of Science, Chiba University, Chiba, (Japan); Han, Soorim [Graduate School of Science, Chiba University, Chiba, (Japan); National Institute of Radiological Science, Chiba, (Japan)

    2015-07-01

    Radioisotopes have been emitted around Japan due to a nuclear accident at the Fukushima Daiichi nuclear power station in March 2011. A problem is the contaminated water including the atomic nucleus which relatively has a long half- life time and soluble such as {sup 90}Sr, {sup 137}Cs. Internal exposures by {sup 90}Sr are more dangerous than {sup 137}Cs's because Sr has effective half-life time of 18 years and property of accumulation in a born. We have developed real-time {sup 90}Sr counter which is sensitive beta-ray of maximum kinematic energy of 2.28 MeV from {sup 90}Sr and insensitive of beta-ray of maximum kinematic energy of 1.17 MeV and gamma-ray from {sup 90}Sr by Cherenkov detection. This counter composes of Cerenkov counter, trigger scintillation counter and veto counter. Silica aerogel for Cherenkov counter can obtain refractive index between 1.017 and 1.049 easily. And wavelength shifting fiber (WLSF) is used as a light guide for extending effective area and producing lower cost. A mechanism of the identification of {sup 90}Sr is explained in following. In case of {sup 90}Sr, when the trigger counter reacts on the beta-ray from {sup 90}Sr, aerogel emits the Cherenkov light and WLSF reacts and read the Cherenkov light. On the other hand, in case of {sup 137}Cs, the trigger counter reacts on the beta-ray, aerogel stops the beta- ray and Cherenkov light is not emitted. Therefore, aerogel has a function as a radiator and shielding material. the gamma-ray is not reacted on the lower density detector. Cosmic rays would be also reacted by the veto counter. A prototype counter whose the effective area is 30 cm x 10 cm was obtained (2.0±1.2){sup 3} of mis-identification as {sup 137}Cs/{sup 90}Sr. Detection limit in the surface contamination inspection depends on measurement time and effective area mainly. The sensitivity of wide range, 10{sup -2} - 10{sup 4} Bq/cm{sup 2}, is obtained by adjustment of detection level in circuit of this counter. A lower

  18. Report on nuclear energy in SR Slovenia; Porocilo o uporabi jedrske energije v SR Sloveniji

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1987-07-01

    Currently Yugoslavia has one 632 MWe nuclear power plant (NPP) of PWR design, located at Krsko in the Socialist Republic (SR) of Slovenia. Krsko NPP, which is a two-loop plant, started power operation in 1981. In general, reactor safety activities in the SR of Slovenia are mostly related to upgrading the safety of our Krsko NPP and to developing capabilities for use in future units. This report presents the nuclear safety related legislation and organization of the corresponding regulatory body, and the activities related to nuclear safety of the participating organizations in the SR of Slovenia in 1987.

  19. Precise determination of δ88Sr in rocks, minerals, and waters by double-spike TIMS: A powerful tool in the study of chemical, geologic, hydrologic and biologic processes

    Science.gov (United States)

    Neymark, Leonid A.; Premo, Wayne R.; Mel'nikov, Nikolay N.; Emsbo, Poul

    2014-01-01

    We present strontium isotopic (88Sr/86Sr and 87Sr/86Sr) results obtained by 87Sr–84Sr double spike thermal ionization mass-spectrometry (DS-TIMS) for several standards as well as natural water samples and mineral samples of abiogenic and biogenic origin. The detailed data reduction algorithm and a user-friendly Sr-specific stand-alone computer program used for the spike calibration and the data reduction are also presented. Accuracy and precision of our δ88Sr measurements, calculated as permil (‰) deviations from the NIST SRM-987 standard, were evaluated by analyzing the NASS-6 seawater standard, which yielded δ88Sr = 0.378 ± 0.009‰. The first DS-TIMS data for the NIST SRM-607 potassium feldspar standard and for several US Geological Survey carbonate, phosphate, and silicate standards (EN-1, MAPS-4, MAPS-5, G-3, BCR-2, and BHVO-2) are also reported. Data obtained during this work for Sr-bearing solids and natural waters show a range of δ88Sr values of about 2.4‰, the widest observed so far in terrestrial materials. This range is easily resolvable analytically because the demonstrated external error (±SD, standard deviation) for measured δ88Sr values is typically ≤0.02‰. It is shown that the “true” 87Sr/86Sr value obtained by the DS-TIMS or any other external normalization method combines radiogenic and mass-dependent mass-fractionation effects, which cannot be separated. Therefore, the “true” 87Sr/86Sr and the δ87Sr parameter derived from it are not useful isotope tracers. Data presented in this paper for a wide range of naturally occurring sample types demonstrate the potential of the δ88Sr isotope tracer in combination with the traditional radiogenic 87Sr/86Sr tracer for studying a variety of biological, hydrological, and geological processes.

  20. Systèmes de type radar appliqués aux domaines routiers et ferroviaires

    OpenAIRE

    DELOOF, P; GHYS, JP; RIVENQ, A; HAESE, N; SAINT-VENANT, M

    2001-01-01

    La détection d'obstacles par radar peut s'appliquer aussi bien au domaine des transports routiers qu'à ceux des transports en commun. Quelques uns de ces systèmes sont étudiés au LEOST dans le cadre du GRRT, Groupement Régional Nord Pas-de-Calais pour la Recherche dans les Transports. La plupart des capteurs micro-ondes furent réalisés par le DHS. Ils étaient fondés soit sur la modulation linéaire en fréquence (FMCW) soit sur la modulation par impulsions. Ces études ont mené à la réalisation ...

  1. Sr isotopic tracer study of the Samail ophiolite, Oman

    International Nuclear Information System (INIS)

    Lanphere, M.A.; Coleman, R.G.; Hopson, C.A.

    1981-01-01

    We have measured Rb and Sr concentrations and Sr isotopic compositions in 41 whole-rock samples and 12 mineral separates from units of the Samail ophiolite, including peridotite, gabbro, plagiogranite diabase dikes, and gabbro and websterite dikes within the metamorphic peridotite. Ten samples of cummulate gabbro from the Wadir Kadir section and nine samples from the Wadi Khafifah section have mean 87 Sr/ 86 Sr ratios and standard deviations of 0.70314 +- 0.00030 and 0.70306 +- 0.00034, respectively. The dispersion in Sr isotopic composition may reflect real heterogeneities in the magma source region. The average Sr isotopic composition of cumulate gabbro falls in the range of isotopic compositions of modern midocean ridge basalt. The 87 Sr/ 86 Sr ratios of noncumulate gabbro, plagiogranite, and diabase dikes range from 0.7034 to 0.7047, 0.7038 to 0.7046, and 0.7037 to 0.7061, respectively. These higher 87 Sr/ 86 Sr ratios are due to alteration of initial magmatic compositions by hydrothermal exchange with seawater. Mineral separates from dikes that cut harzburgite tectonite have Sr isotopic compositions which agree with that of cumulate gabbro. These data indicate that the cumulate gabbro and the different dikes were derived from partial melting of source regions that had similar long-term histories and chemical compositions

  2. Thermal infrared and microwave absorbing properties of SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/polyaniline nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, Seyed Hossein, E-mail: shhosseini@iiau.ac.ir [Department of Chemistry, Faculty of Science, Islamshahr Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Zamani, Parisa [Department of Applied Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Mousavi, S.Y. [Faculty of Passive Defense, Imam Hossein University, Tehran (Iran, Islamic Republic of)

    2015-09-25

    Graphical abstract: We have developed a new perspective of applications and properties of conducting polymers. The combination of absorption ability prepared nanocomposites in the present of PANI display a great potential in organization of shielding structures into thermal IR and microwave. Further investigations using other conducting polymers to demonstrate their capability for advance thermal IR and microwave shielding devices is under way. The application of these samples may improve the IR thermographic detection, catalysis, sensors, magnetic data storage, electromagnetic resonance wave absorption, photonic crystals, and microelectronic devices and military aspects. - Highlights: • The SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/PANI exhibited electric and electromagnetic properties. • The SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/PANI has shielding structures into thermal IR and microwave. • Increasing weight ratios and thicknesses will increase thermal IR ability. • Increasing weight ratios and thicknesses will increase microwave absorption ability. - Abstract: Polyaniline (PANI) as a unique polymer that also has electromagnetic absorption used as the substrate. In this research, SrTiO{sub 3} was synthesized as IR absorbent and core and then SrFe{sub 12}O{sub 19} as microwave absorbent was prepared on SrTiO{sub 3} via co-precipitation method as the first shell. As the next step, PANI was coated on SrTiO{sub 3}/SrFe{sub 12}O{sub 19} nanoparticles via in situ polymerization by multi core–shell structures (SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/PANI). Nanometer size and structures of samples were measured by TEM, XRD and FTIR. Morphology of nanocomposite was showed by SEM images. The magnetic and electric properties were also performed by VSM and four probe techniques. Thermal infrared (IR) absorption and microwave reflection loss of nanocomposites were investigated at 10–40 μm and 8–12 GHz, IR and microwave frequencies, respectively. The results showed that the Sr

  3. 82Sr--82Rb radioisotope generator

    International Nuclear Information System (INIS)

    Grant, P.M.; Erdal, B.R.; O'Brien, H.A.

    1976-01-01

    An improved 82 Sr- 82 Rb radioisotope generator system, based upon the complexing ion exchange resin Chelex-100, has been developed. Columns of this material can be easily and rapidly milked, and the Rb-Sr separation factor for a fresh generator was found to be greater than 10 7 . Approximately 80 percent of the 82 Rb present was delivered in a 15-ml volume of aqueous 0.2 M NH 4 Cl solution. After more than 6 liters of eluant had been put through the generator, the Rb-Sr separation factor was still observed to be greater than 10 5 , and no unusual strontium breakthrough behavior was seen in the system over nearly three 82 Sr half lives. 2 claims, no drawings

  4. Autoradiography of 90Sr in developing rats

    International Nuclear Information System (INIS)

    Olsen, I.; Jonsen, J.

    1979-01-01

    The distribution patterns of 90 Sr in five littermate, 8-day-old Wistar rats were studied by whole body autoradiography. Rats were killed 15 min, 1, 4, 24, and 72 h after a single intraperitoneal injection of the isotope. Immediately after administration, 90 Sr was distributed throughout most of the soft tissues of the body. The soft tissue deposits had practically disappeared after 4 h. In the hard tissues of the body 90 Sr accumulated up to 24-72 h. Fifteen minutes after injection the uptake of 90 Sr in the enamel of the teeth was highest in the occlusal and incisal regions. 90 Sr gradually accumulated throughout the enamel and after 72 h its distribution in this layer was fairly uniform. Immediately after injection a narrow zone of radioactivity appeared in the dentin near the pulp. This zone broadened with time towards the dentinoenamel junction and included the intire dentin layer 72 h after injection. Initially, the uptake of 90 Sr was higher in the dentin than in the enamel, particularly in the cervical areas of the crown. This difference became less apparent with time. There was good correlation between the uptake in the teeth and bones, supporting the use of teeth as indicators of the 90 Sr body burden. (author)

  5. Determination of 90Sr by liquid scintillation counting

    International Nuclear Information System (INIS)

    Cerchetti, Maria L.; Aghazarian, V.P.

    2006-01-01

    99m Tc, the result of the radioactive decay of 99 Mo, is one of the most applied radioisotopes in nuclear medicine and is used in nuclear medicine as a radiopharmaceutical product. It is important to ensure 99 Mo quality in order to fit the 99m Tc quality specifications. The main objective was to obtain a technique for 90 Sr determination in 99 Mo and environmental samples. The purification of 90 Sr is performed by extraction chromatography where crown-ether resin (Sr-Spec, Eichrom) was used. The measurement of the 90 Sr activity is performed by Liquid Scintillation Counting (LSC) using the double windows method. This method permits the 90 Sr determination without waiting until radiochemical equilibrium 90 Sr / 90 Y has been reached. The recovery factor was determined by gamma spectrometry with 85 Sr, and by gravimetry with stable strontium carrier solution. The minimum detectable activity was 0,05 Bq. The recovery factor was the major contribution in the total uncertainty. (author)

  6. Test for the determination of 90Sr in soil

    International Nuclear Information System (INIS)

    1980-01-01

    The standardized method is based on the chemical separation (extraction, precipitation, etc.) of 90 Sr from other fission products. After long-term storage for 90 Sr- 90 Y equilibrium the activity of the sample precipitated in the form of Y(COO) 2 is measured. The Sr yield coefficient is determined by 85 Sr tracer or by gravimetry. The test is applicable for the determination of 90 Sr contamination originating from fallout or from other sources in soil, when the concentration of 90 Sr is higher than 0.2-0.4 Bqg -1 (5-10 pCig -1 ). The error of the method is less than +-2% of the amount of the 90 Sr present. (Sz.J.)

  7. Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO{sub 3}){sub n} films by means of metalorganic aerosol deposition

    Energy Technology Data Exchange (ETDEWEB)

    Jungbauer, M.; Hühn, S.; Moshnyaga, V. [Erstes Physikalisches Institut, Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G. [EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

    2014-12-22

    We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO{sub 3}){sub n} (n = ∞, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO{sub 3}(001) substrates by means of a sequential deposition of Sr-O/Ti-O{sub 2} atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2–4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5–6 repetitions of the SrO(SrTiO{sub 3}){sub 4} block at the level of 2.4%. This identifies the SrTiO{sub 3} substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy.

  8. BUSY: Una plataforma para la gestión de reservas por hora en PyMes

    OpenAIRE

    González Cabrero, Juan Carlos

    2016-01-01

    El objetivo de este proyecto consiste en el desarrollo de una plataforma software enfocada a pequeñas y medianas empresas (PyMEs), para llevar a cabo la organización de servicios ofrecidos a los clientes. buSy es una herramienta cómoda y sencilla para la gestión de reservas y control de horarios con un ámbito de negocio generalista, ya que su enfoque global permite la utilización de esta aplicación a una amplia gama de categorías de empresa. Se trata de un proyecto web desar...

  9. Factores asociados con lactancia materna exclusiva hasta el sexto mes en madres adolescentes. medellin, 2010

    OpenAIRE

    Gómez Aristizábal, Liliana Yanet; Díaz Ruíz, Carlos Eduardo; Manrique Hernández, Ruben Dario

    2013-01-01

    Objetivo Determinar los factores asociados con la lactancia materna exclusiva hasta el sexto mes en madres adolescentes de los niveles I y II del SISBEN de la ciudad de Medellín.Métodos Se realizó un estudio de casos y controles con 323 madres adolescentes, 197 casos y 126 controles de la “Estrategia Buen Comienzo Había una Vez-BCHV” de Metrosalud y la Alcaldía de Medellín. Se aplicó estadística descriptiva para el análisis univariado. Se hizo un análisis de correspondencias. La comparación d...

  10. Thermodynamique statistique résumés de cours et problèmes résolus

    CERN Document Server

    Chahine, C

    1976-01-01

    Le présent ouvrage est conçu pour une initiation à la thermodynamique statistique en présentant un très grand nombre d'applications sous forme de problèmes résolus, et en donnant des résumés de cours constitués de l'essentiel des résultats théoriques nécessaires pour traiter les applications chaque fois qu'est abordé un nouveau domaine. Partant d'un niveau élémentaire et rédigé de façon très progressive, ce livre qui se suffit à lui-même, permet de saisir l'aspect physique des phénomènes, et de faire le lien entre les statistiques élémentaires et les statistiques de Gibbs. Le lecteur pourra, soit résoudre effectivement les problèmes sans avoir recours à la solution et tirer alors tout le bénéfice d'une recherche personnelle, soit lire l'ensemble de l'énoncé et de la solution qui sont très détaillés, et forment ainsi un exposé très clair. L'ouvrage, qui développe principalement l'aspect physique des phénomènes, intéresse les étudiants en physique dès la 1ère année ...

  11. Interplay between HIV Entry and Transportin-SR2 Dependency

    Directory of Open Access Journals (Sweden)

    Gijsbers Rik

    2011-01-01

    Full Text Available Abstract Background Transportin-SR2 (TRN-SR2, TNPO3, transportin 3 was previously identified as an interaction partner of human immunodeficiency virus type 1 (HIV-1 integrase and functions as a nuclear import factor of HIV-1. A possible role of capsid in transportin-SR2-mediated nuclear import was recently suggested by the findings that a chimeric HIV virus, carrying the murine leukemia virus (MLV capsid and matrix proteins, displayed a transportin-SR2 independent phenotype, and that the HIV-1 N74D capsid mutant proved insensitive to transportin-SR2 knockdown. Results Our present analysis of viral specificity reveals that TRN-SR2 is not used to the same extent by all lentiviruses. The DNA flap does not determine the TRN-SR2 requirement of HIV-1. We corroborate the TRN-SR2 independent phenotype of the chimeric HIV virus carrying the MLV capsid and matrix proteins. We reanalyzed the HIV-1 N74D capsid mutant in cells transiently or stably depleted of transportin-SR2 and confirm that the N74D capsid mutant is independent of TRN-SR2 when pseudotyped with the vesicular stomatitis virus glycoprotein (VSV-G. Remarkably, although somewhat less dependent on TRN-SR2 than wild type virus, the N74D capsid mutant carrying the wild type HIV-1 envelope required TRN-SR2 for efficient replication. By pseudotyping with envelopes that mediate pH-independent viral uptake including HIV-1, measles virus and amphotropic MLV envelopes, we demonstrate that HIV-1 N74D capsid mutant viruses retain partial dependency on TRN-SR2. However, this dependency on TRN-SR2 is lost when the HIV N74D capsid mutant is pseudotyped with envelopes mediating pH-dependent endocytosis, such as the VSV-G and Ebola virus envelopes. Conclusion Here we discover a link between the viral entry of HIV and its interaction with TRN-SR2. Our data confirm the importance of TRN-SR2 in HIV-1 replication and argue for careful interpretation of experiments performed with VSV-G pseudotyped viruses in

  12. 44/40Ca and 87Sr/86Sr isotopes as tracers of silicate weathering in small catchments of the Massif Central, France

    Science.gov (United States)

    Négrel, Philippe; Guerrot, Catherine; Millot, Romain; Petelet-Giraud, Emmanuelle; Bullen, Thomas

    2013-04-01

    We present calcium stable isotope and strontium radiogenic isotope data for soils and sediments developed on volcanic and igneous rocks forming small catchments in the Massif Central (France). Measurements of 44/40Ca isotope ratios (44/40Ca measured by the double spike method on TIMS and normalized to the value for seawater Ca in delta units) in rocks, sediments and soils from silicate catchments (e.g. granite and basalts) together with 87Sr/86Sr isotope ratios permit an examination of the relationships of these isotope systematics during weathering of silicate rocks. We have analysed the granite, weathered granite (arene) and saprolite, sediment and soil overlying the granite on one hand and the basanite, sediment and soil overlying the basanite on the other. The main bedrock in the volcanic zone (e.g. Allanche catchment) is 11 to 2.5 Ma basanite (nephelinitic to leucitic basalts) having SiO2 between 41-45 wt. %, Na2O + K2O bank have 87Sr/86Sr ratios greater than that of the arene with values increasing in the sediment from the surface down to soil. The 87Sr/86Sr vs. Rb/Sr variation observed in the volcanic area likewise confirms the weathering of low 87Sr/86Sr, low Rb/Sr phases in the bedrock, and there is a linear increase in 87Sr/86Sr and Rb/Sr ratios from those in the sediment up to the values observed in the soils. In the volcanic area, the basanite bedrock has 44/40Ca = -0.94 ± 0.05‰ (n = 7), while the soils and sediments have 44/40Ca of -0.75 to -1.13‰ and -0.79 to -1.01‰, respectively. These results suggest that Ca isotopes are not strongly fractionated during weathering of the basalt. The granite whole-rock has 44/40Ca of -1.29‰, while the soil and sediments have 44/40Ca of -1.93 to -2.07‰ and -1.98 to -2.81‰, respectively, with values decreasing as the Ca content decreases. The 44/40Ca ratios of arene, soil and sediment are similar to or less than that of K- feldspar, reflecting complete loss of the relatively heavy Ca from plagioclase and

  13. Molecular Environmental Science and Synchrotron Radiation Facilities An Update of the 1995 DOE-Airlie Report on Molecular Environmental Science

    Energy Technology Data Exchange (ETDEWEB)

    Bargar, John R

    1999-05-07

    This workshop was requested by Dr. Robert Marianelli, Director of the DOE-BES Chemical Sciences Division, to update the findings of the Workshop on Molecular Environmental Sciences (MES) held at Airlie, VA, in July 1995. The Airlie Workshop Report defined the new interdisciplinary field referred to as Molecular Environmental Science (MES), reviewed the synchrotron radiation methods used in MES research, assessed the adequacy of synchrotron radiation facilities for research in this field, and summarized the beam time requirements of MES users based on a national MES user survey. The objectives of MES research are to provide information on the chemical and physical forms (speciation), spatial distribution, and reactivity of contaminants in natural materials and man-made waste forms, and to develop a fundamental understanding of the complex molecular-scale environmental processes, both chemical and biological, that affect the stability, transformations, mobility, and toxicity of contaminant species. These objectives require parallel studies of ''real'' environmental samples, which are complicated multi-phase mixtures with chemical and physical heterogeneities, and of simplified model systems in which variables can be controlled and fundamental processes can be examined. Only by this combination of approaches can a basic understanding of environmental processes at the molecular-scale be achieved.

  14. Molecular Environmental Science and Synchrotron Radiation Facilities An Update of the 1995 DOE-Airlie Report on Molecular Environmental Science

    International Nuclear Information System (INIS)

    Bargar, John R

    1999-01-01

    This workshop was requested by Dr. Robert Marianelli, Director of the DOE-BES Chemical Sciences Division, to update the findings of the Workshop on Molecular Environmental Sciences (MES) held at Airlie, VA, in July 1995. The Airlie Workshop Report defined the new interdisciplinary field referred to as Molecular Environmental Science (MES), reviewed the synchrotron radiation methods used in MES research, assessed the adequacy of synchrotron radiation facilities for research in this field, and summarized the beam time requirements of MES users based on a national MES user survey. The objectives of MES research are to provide information on the chemical and physical forms (speciation), spatial distribution, and reactivity of contaminants in natural materials and man-made waste forms, and to develop a fundamental understanding of the complex molecular-scale environmental processes, both chemical and biological, that affect the stability, transformations, mobility, and toxicity of contaminant species. These objectives require parallel studies of ''real'' environmental samples, which are complicated multi-phase mixtures with chemical and physical heterogeneities, and of simplified model systems in which variables can be controlled and fundamental processes can be examined. Only by this combination of approaches can a basic understanding of environmental processes at the molecular-scale be achieved

  15. In situ Sr/Sr investigation of igneous apatites and carbonates using laser-ablation MC-ICP-MS

    DEFF Research Database (Denmark)

    Bizzarro, Martin; Simonetti, A.; Stevenson, R.K.

    2003-01-01

    In situ Sr isotopic compositions of coexisting apatite and carbonate for carbonatites from the Sarfartoq alkaline complex, Greenland, have been determined by laser-ablation multicollector inductively coupled plasma mass spectrometry. This study is the first to examine the extent of Sr isotopic ho...

  16. Hybrid HF-DFT comparative study of SrZrO{sub 3} and SrTiO{sub 3}(001) surface properties

    Energy Technology Data Exchange (ETDEWEB)

    Evarestov, R.A.; Bandura, A.V.; Alexandrov, V.E. [Department of Quantum Chemistry, St. Petersburg State University, 26 Universitetskii Prospekt, Stary Petergof, 198504 St. Petersburg (Russian Federation)

    2006-10-15

    Hybrid HF-DFT LCAO simulations of SrZrO{sub 3} and SrTiO{sub 3}(001) surface properties are performed in a single-slab model framework. The SrZrO{sub 3}(001) surface was studied by an ab initio method for the first time. Three slab models with different surface terminations including up to 8 atomic planes were used for calculation of the various surface characteristics (surface energies, atomic charges, density of electronic states). The dependence of the results on the chosen model and on the kind of d-element is analyzed. The dissimilarity in the surface oxygen atom contributions to the total density of states of two crystals is attributed to the more ionic nature of Zr-O bonds compared to Ti-O bonds. It is found that in the case of SrZrO{sub 3} the electronic density is biased towards the SrO-terminated surface and this surface should be more basic in nature than the SrO surface of SrTiO{sub 3} crystal. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  17. PSA de radio Mes de Concientización sobre las ETS PSA de radio (30 seg) (STD Awareness Month PSA (:30))

    Centers for Disease Control (CDC) Podcasts

    Abril es el Mes Nacional de Concientización sobre las Enfermedades de Transmisión Sexual (ETS). Las ETS pueden afectar a cualquier persona. Muchas ETS no tienen síntomas, por lo que es importante hacerse pruebas de detección.

  18. Determination of the electrostatic potential distribution in Pt/Fe:SrTiO₃/Nb:SrTiO₃ thin-film structures by electron holography.

    Science.gov (United States)

    Marchewka, Astrid; Cooper, David; Lenser, Christian; Menzel, Stephan; Du, Hongchu; Dittmann, Regina; Dunin-Borkowski, Rafal E; Waser, Rainer

    2014-11-10

    We determined the electrostatic potential distribution in pristine Pt/Fe:SrTiO3/Nb:SrTiO3 structures by electron holography experiments, revealing the existence of a depletion layer extending into the Nb-doped bottom electrode. Simulations of potential profiles in metal-insulator-metal structures were conducted assuming different types and distributions of dopants. It is found that the presence of acceptor-type dopant concentrations at the Fe:SrTiO3/Nb:SrTiO3 interface with a donor-doped insulating layer provides a good match to the measured profile. Such acceptor-type interface concentrations may be associated with Sr vacancies on the Nb:SrTiO3 side of the bottom interface.

  19. Using noble gases and 87Sr/86Sr to constrain heat sources and fluid evolution at the Los Azufres Geothermal Field, Mexico

    Science.gov (United States)

    Wen, T.; Pinti, D. L.; Castro, M. C.; Lopez Hernandez, A.; Hall, C. M.; Shouakar-Stash, O.; Sandoval-Medina, F.

    2017-12-01

    Geothermal wells and hot springs were sampled for noble gases' volume fraction and isotopic measurements and 87Sr/86Sr in the Los Azufres Geothermal Field (LAGF), Mexico, to understand the evolution of fluid circulation following three decades of exploitation and re-injection of used brines. The LAGF, divided into the Southern Production Zone (SPZ) and the Northern Production Zone (NPZ), is hosted in a Miocene to Pliocene andesitic volcanic complex covered by Quaternary rhyolitic-dacitic units. Air contamination corrected 3He/4He ratios (Rc) normalized to the atmospheric ratio (Ra=1.384 x 10-6), show a median value of 6.58 indicating a dominant mantle helium component. Contributions of crustal helium up to 53% and 18% are observed in NPZ and SPZ, respectively. Observations based on Rc/Ra and 87Sr/86Sr ratios points to the mixing of three magmatic sources supplying mantle helium to the LAGF: (1) a pure mantle He (Rc/Ra = 8) and Sr (87Sr/86Sr = 0.7035) source; (2) a pure mantle helium (Rc/Ra = 8) with some radiogenic Sr (87Sr/86Sr = 0.7049) source possibly resulting from Quaternary rhyolitic volcanism; and (3) a fossil mantle He component (Rc/Ra = 3.8) with some radiogenic Sr (87Sr/86Sr = 0.7038), corresponding possibly to the Miocene andesite reservoir. Intrusions within the last 50 kyrs from sources (1) and (2) are likely responsible for the addition of mantle volatiles and heat to the hydrothermal system of Los Azufres. He and Ar isotopes indicate that heat flow is transported by both convection and conduction. Atmospheric noble gas elemental ratios suggest that geothermal wells located closer to the western re-injection zone are beginning to be dominated by re-injection of used brines (injectate). The area affected by boiling in LAGF has further extended to the north and west since the last noble gas sampling campaign in 2009.

  20. Thermodynamic modeling of the Sr-Co-Fe-O system

    DEFF Research Database (Denmark)

    Zhang, Wei Wei; Povoden-Karadeniz, Erwin; Chen, Ming

    2016-01-01

    This paper reviews and assesses phase equilibria and thermodynamic properties of phases in the Sr-Co-Fe-O system, with a focus on oxides, especially the SrCo1 - xFexO3 - δ perovskite. In our work, the SrCo1 - xFexO3 - δ perovskite was modeled with a three-sublattice model, where the three...... sublattices correspond to the A, B and oxygen sites in an ABO3 perovskite, respectively. A number of other important ternary oxide phases in Sr-Co-O and Sr-Co-Fe-O were also considered. Available thermodynamic and phase diagram data were carefully assessed. A thermodynamic description of Sr-Co-O was derived...... using the CALPHAD approach and was further extrapolated to that of Sr-Co-Fe-O. The thermodynamic database of Sr-Co-Fe-O established in this work allows for calculating phase diagrams, thermodynamic properties, cation distribution and defect chemistry properties, and therefore enables material...

  1. Factors affecting 90Sr uptake from the ration

    International Nuclear Information System (INIS)

    Knizhnikov, V.A.; Marej, A.N.; Borisov, B.K.; Petukhova, Eh.V.

    1980-01-01

    The dependence of 90 Sr uptake in the human organism on nutrition peculiarities is shown. Strontium-90 polluting vegetable products due to particle sorption from the air is less available for the uptake than 90 Sr resorbed from the soil with vegetation. Therefore, this nuclide is uptaken more completely from milk which containes 90 Sr in a soluble form than from grain and bakery products which are polluted by 90 Sr largely by air

  2. Decoupling of unpolluted temperate forests from rock nutrient sources revealed by natural 87Sr/86Sr and 84Sr tracer addition

    Science.gov (United States)

    Kennedy, Martin J.; Hedin, Lars O.; Derry, Louis A.

    2002-01-01

    An experimental tracer addition of 84Sr to an unpolluted temperate forest site in southern Chile, as well as the natural variation of 87Sr/86Sr within plants and soils, indicates that mechanisms in shallow soil organic horizons are of key importance for retaining and recycling atmospheric cation inputs at scales of decades or less. The dominant tree species Nothofagus nitida feeds nearly exclusively (>90%) on cations of atmospheric origin, despite strong variations in tree size and location in the forest landscape. Our results illustrate that (i) unpolluted temperate forests can become nutritionally decoupled from deeper weathering processes, virtually functioning as atmospherically fed ecosystems, and (ii) base cation turnover times are considerably more rapid than previously recognized in the plant available pool of soil. These results challenge the prevalent paradigm that plants largely feed on rock-derived cations and have important implications for understanding sensitivity of forests to air pollution. PMID:12119394

  3. Size exclusion chromatography for semipreparative scale separation of Au38(SR)24 and Au40(SR)24 and larger clusters.

    Science.gov (United States)

    Knoppe, Stefan; Boudon, Julien; Dolamic, Igor; Dass, Amala; Bürgi, Thomas

    2011-07-01

    Size exclusion chromatography (SEC) on a semipreparative scale (10 mg and more) was used to size-select ultrasmall gold nanoclusters (<2 nm) from polydisperse mixtures. In particular, the ubiquitous byproducts of the etching process toward Au(38)(SR)(24) (SR, thiolate) clusters were separated and gained in high monodispersity (based on mass spectrometry). The isolated fractions were characterized by UV-vis spectroscopy, MALDI mass spectrometry, HPLC, and electron microscopy. Most notably, the separation of Au(38)(SR)(24) and Au(40)(SR)(24) clusters is demonstrated.

  4. Thermodynamic modeling of the Sr-Co-Fe-O system

    DEFF Research Database (Denmark)

    Zhang, Wei Wei; Povoden-Karadeniz, Erwin; Chen, Ming

    2016-01-01

    This paper reviews and assesses phase equilibria and thermodynamic properties of phases in the Sr-Co-Fe-O system, with a focus on oxides, especially the SrCo1 - xFexO3 - δ perovskite. In our work, the SrCo1 - xFexO3 - δ perovskite was modeled with a three-sublattice model, where the three...... sublattices correspond to the A, B and oxygen sites in an ABO3 perovskite, respectively. A number of other important ternary oxide phases in Sr-Co-O and Sr-Co-Fe-O were also considered. Available thermodynamic and phase diagram data were carefully assessed. A thermodynamic description of Sr-Co-O was derived...

  5. The 87Sr/86Sr aquatic isoscape of the Danube catchment from the source to the mouth as tool for studying fish migrations

    Science.gov (United States)

    Zitek, Andreas; Tchaikovsky, Anastassiya; Irrgeher, Johanna; Waidbacher, Herwig; Prohaska, Thomas

    2014-05-01

    Isoscapes - spatially distributed isotope patterns across landscapes - are increasingly used as important basis for ecological studies. The natural variation of the isotopic abundances in a studied area bears the potential to be used as natural tracer for studying e.g. migrations of animals or prey-predator relations. The 87Sr/86Sr ratio is one important tracer, since it is known to provide a direct relation of biological samples to geologically distinct regions, as Sr isotopes are incorporated into living tissues as a proxy for calcium and taken up from the environment without any significant fractionation. Although until now the focus has been mainly set on terrestrial systems, maps for aquatic systems are increasingly being established. Here we present the first 87Sr/86Sr aquatic isoscape of the Danube catchment, the second largest river catchment in Europe, from near its source starting at river km 2581 in Germany down to its mouth to river km 107 in Romania. The total length of the river Danube is 2780 km draining a catchment area 801 463 km2 (10 % of the European continent). The major purpose of this study was to assess the potential of the 87Sr/86Sr isotope ratio to be used as tool for studying fish migrations at different scales in the entire Danube catchment. Within the Joint Danube Research 3 (JDS 3), the biggest scientific multi-disciplinary river expedition of the World in 2013 aiming at the assessment of the ecological status and degree of human alterations along the river Danube, water samples were taken at 68 pre-defined sites along the course of the river Danube including the major tributaries as a basis to create the so called 'Isoscape of the Danube catchment'. The determination of 87Sr/86Sr isotope ratio in river water was performed by multicollector-sector field-inductively coupled plasma-mass spectrometry (MC-SF-ICP-MS). The JDS 3 data were combined with existing data from prior studies conducted within the Austrian part of the Danube catchment

  6. Rapid determination of 90Sr in seawater

    International Nuclear Information System (INIS)

    Pavlotskaya, F.I.; Moskin, A.I.

    1994-01-01

    A method for determining 90 Sr in seawater that is based on direct isolation and radiochemical purification of daughter 90 Y is proposed. The analysis time is 6-8 h. The chemical yield of the Y-carrier during the 90 Sr determination from 35 liters of seawater varies in the range 37-69%. The analysis uncertainty is 90 Sr from seawater and subsequent isolation of 90 Y

  7. La trajectoire des symptômes dépressifs de l'enfance à l'adolescence et les cibles d'intervention préventive

    Directory of Open Access Journals (Sweden)

    Diane Marcotte

    2014-03-01

    Full Text Available Cette étude longitudinale s'intéresse à la trajectoire développementale des symptômes de dépression sur une période de cinq ans entre l'enfance et l'adolescence ainsi qu'à ses facteurs associés. À partir de l'analyse de courbes de croissance latente (Latent Growth Model-LGM, les résultats indiquent que les symptômes de dépression augmentent entre l'âge de 11-12 ans et 15-16 ans chez les filles, mais non chez les garçons. Cependant, pour chacun des sexes, la variance de la pente de la trajectoire reflète l'hétérogénéité des sous-groupes, révélant que les trajectoires varient chez les individus. Parmi les facteurs mesurés au temps 1 de l'étude, ceux qui sont le plus étroitement associés à la variation longitudinale des symptômes dépressifs sont le soutien des amis pour les deux genres et l'âge pour les filles. Plusieurs facteurs sont également associés à la présence de dépression au temps initial. Les cibles d'intervention pour une prévention universelle de la dépression chez les jeunes sont ensuite discutées et un programme visant le développement de facteurs de protection chez les adolescents est présenté

  8. PRODUCTION OF PLANTARCIN BY LACTOBACILLUS PLANTARUM SR18

    Directory of Open Access Journals (Sweden)

    Wagih El-Shouny

    2012-06-01

    Full Text Available Out of 86 lactobacilli previously screened in our laboratory, Lactobacillus plantarum SR18 isolated from yoghurt revealed the largest detected inhibition zone against the selected indicator Streptococcus salivarius 5. The obtained electrophoretic patterns revealed that L. plantarum SR18 was free from plasmids. Exposure of 6 h growing L. plantarum culture to T-8M, 3B ultraviolet B lamp (8w, 220v & 312 nm for 2 h and subsequent growth for further 24 h resulted in an increase of cell-bound bacteriocin titer reached 2 fold at 12 h. Whereas bacteriocin secreted in the culture filtrate was not affected by UV irradiation. Plantarcin SR18 production was maximal (12800 AU/ml between 12 and 18 h by incubation of the culture at 37°C and pH 5-7 in candle jar (CO2. The bacteriocin bound to the cells and that secreted into the culture filtrate of L. plantarum SR18 were precipitated by 75% ammomium sulphate, dialysed and further purified by Gel filtration on Sephadex G-100. The specific activities (AU/mg protein were increased by a factor of about 5.3 and 2.35 for plantarcins purified from proteins bound to the cell of L. plantarum SR18 (plantarcin SR18 a and that secreted into the culture filtrate (plantarcin SR18 b, respectively. Gel filtration of plantarcin SR18a resulted in moderate antibacterial activity (3200 AU/ml and very high activity (25600 AU/ml of plantarcin SR18b.

  9. 90Sr and 89Sr in seawater off Japan as a consequence of the Fukushima Dai-ichi nuclear accident

    Directory of Open Access Journals (Sweden)

    N. Casacuberta

    2013-06-01

    Full Text Available The impact of the earthquake and tsunami on the east coast of Japan on 11 March 2011 caused a loss of power at the Fukushima Dai-ichi nuclear power plant (NPP that resulted in one of the most important releases of artificial radioactivity into the environment. Although several works were devoted to evaluating the atmospheric dispersion of radionuclides, the impact of the discharges to the ocean has been less investigated. Here we evaluate the distribution of Fukushima-derived 90Sr (n = 57 and 89Sr (n = 19 throughout waters 30–600 km offshore in June 2011. Concentrations of 90Sr and 89Sr in both surface waters and shallow profiles ranged from 0.8 ± 0.2 to 85 ± 3 Bq m−3 and from 19 ± 6 to 265 ± 74 Bq m−3, respectively. Because of its short half-life, all measured 89Sr was due to the accident, while the 90Sr concentrations can be compared to the background levels in the Pacific Ocean of about 1.2 Bq m−3. Fukushima-derived radiostrontium was mainly detected north of Kuroshio Current, as this was acting as a southern boundary for transport. The highest activities were associated with near-shore eddies, and larger inventories were found in the closest stations to Fukushima NPP. The data evidence a major influence of direct liquid discharges of radiostrontium compared to the atmospheric deposition. Existing 137Cs data reported from the same samples allowed us to establish a 90Sr / 137Cs ratio of 0.0256 ± 0.0006 in seawater off Fukushima, being significantly different than that of the global atmospheric fallout (i.e., 0.63 and may be used in future studies to track waters coming from the east coast of Japan. Liquid discharges of 90Sr to the ocean were estimated, resulting in an inventory of 53 ± 1 TBq of 90Sr in the inshore study area in June 2011 and total releases of 90Sr ranging from 90 to 900 TBq, depending upon the reported estimates of 137Cs releases that are considered.

  10. Crystal structures of KM(AsF6)3 (M2+ = Mg, Co, Mn, Zn), KCu(SbF6)3 and [Co(HF)2]Sr[Sr(HF)]2-[Sr(HF)2]2[AsF6]12

    International Nuclear Information System (INIS)

    Mazej, Zoran; Goreshnik, Evgeny

    2015-01-01

    The KM(AsF 6 ) 3 (M 2+ = Mg, Co, Mn, Zn) and KCu(SbF 6 ) 3 compounds crystallize isotypically to previously known KNi(AsF 6 ) 3 . The main features of the structure of these compounds are rings of MF 6 octahedra sharing apexes with AsF 6 octahedra connected into infinite tri-dimensional frameworks. In this arrangement cavities are formed where K + cations are placed. Single crystals of CoSr 5 (AsF 6 ) 12 .8HF were obtained as one of the products after the crystallization of 3KF/CoF 2 /SrF 2 mixture in the presence of AsF 5 in anhydrous HF. The CoSr 5 (AsF 6 ) 12 .8HF is monoclinic, C/2c (No.15), with a = 26.773(5) Aa, b = 10.087(2) Aa, c = 21.141(5) Aa, β = 93.296(13) circle , V = 5699.9(19) Aa 3 at 200 K, and Z = 4. There are three crystallographically non-equivalent Sr 2+ cations in the crystal structure of CoSr 5 (AsF 6 ) 12 .8HF. The Sr1 is coordinated by ten fluorine atoms from eight different [AsF 6 ]- anions, meanwhile Sr2 and Sr3 are bound to nine fluorine atoms provided by one HF and eight AsF 6 units or by two HF and six AsF 6 units, respectively. The Co 2+ is coordinated distorted-octahedrally by six fluorine atoms from two HF molecules and four different AsF 6 units. All those moieties in the crystal structure of [Co(HF) 2 ]Sr[Sr(HF)] 2 [Sr(HF) 2 ] 2 [AsF 6 ] 12 are connected into tridimensional framework. The CoSr 5 (AsF 6 ) 12 .8HF is a unique example of compound where HF molecules are directly bound via fluorine atoms to two different metal centres.

  11. Geographical distribution of 90Sr contamination in Poland

    International Nuclear Information System (INIS)

    Gaca, P.; Mietelski, J.W.; Skwarzec, B.

    2006-01-01

    The paper presents results on determination of 90 Sr in bilberry and cowberry leaves (Vaccinium myrtillus and Vaccinium vitis-idaea) and the use of these plants as bio-monitors of radiostrontium contamination in Poland. Radiostrontium was determined by mean of liquid scintillation spectrometry preceded by radiochemical separation using Sr-resin and 85 Sr tracer. The approximate map of 90 Sr contamination of Poland is presented. The activity ratio between 90 Sr and obtained earlier data for 137 Cs in the same samples is discussed. The enhancement of radiostrontium content observed in northeastern Poland seems to be the trace of hot-particles fallout from initial Chernobyl cloud, which passed over Polish territory toward Scandinavia. (orig.)

  12. Contrasting pressure effects in Sr2VFeAsO3 and Sr2ScFePO3

    International Nuclear Information System (INIS)

    Kotegawa, Hisashi; Kawazoe, Takayuki; Tou, Hideki; Murata, Keizo; Ogino, Hiraku; Kishio, Kohji; Shimoyama, Jun-ichi

    2009-01-01

    We report the resistivity measurements under pressure of two Fe-based superconductors with a thick perovskite oxide layer, Sr 2 VFeAsO 3 and Sr 2 ScFePO 3 . The superconducting transition temperature T c of Sr 2 VFeAsO 3 markedly increases with increasing pressure. Its onset value, which was T c onset =36.4 K at ambient pressure, increases to T c onset =46.0 K at ∼4 GPa, ensuring the potential of the '21113' system as a high-T c material. However, the superconductivity of Sr 2 ScFePO 3 is strongly suppressed under pressure. The T c onset of ∼16 K decreases to ∼5 K at ∼4 GPa, and the zero-resistance state is almost lost. We discuss the factor that induces this contrasting pressure effect. (author)

  13. Rb-Sr ages and initial 87Sr/86Sr ratios of late paleozoic granitic rocks from northern Chile

    International Nuclear Information System (INIS)

    Shibata, Ken; Ishihara, Shunso; Ulriksen, C.E.

    1984-01-01

    Rb-Sr whole-rock isochron ages were determined on three suites of so-called Paleozoic granitic rocks from northern coastal Chile. The granitic rocks from the Valparaiso and Ci Funcho areas are dated as 296.3 +- 5.4 Ma and 262.2 +- 4.6 Ma, respectively, which are in accord with geologically estimated age. The rocks from the Chanaral area is dated as 212.8 +- 8.6 Ma, which is correlated close to the Triassic-Jurassic boundary age. A K-Ar age of 196 +- 6 Ma was obtained on biotite in granite from Esmeralda between Ci Funcho and Chanaral. These age results demonstrate that no Precambrian plutonism occurred in the studied area, and that so-called Paleozoic granitic rocks in the Ci Funcho-Chanaral area are divided into Permian and early Mesozoic in age. Initial 87 Sr/ 86 Sr ratios of the ilmenite-series granitic rocks from the coastal region are 0.70641 (Valparaiso), 0.70635 (Ci Funcho) and 0.70455 (Chanaral). These relatively low ratios deny substantial crustal contribution to the granitoids. The initial ratios of magnetite-series granitoids from porphyry- and manto-type mineralized areas (Chiquicamata, El Salvador and Tocopilla) are as low as 0.70344 to 0.70464. (author)

  14. 87Sr/86Sr variations in basalts of Late Eocene-Early Miocene series in Eastern Sikhoteh-Alin

    International Nuclear Information System (INIS)

    Esin, S.V.; Ponomarchuk, V.A.; Shipitsyn, Yu.G.; Palesskij, Yu.G.

    1993-01-01

    Late Eocene high-alumina and Oligocene high-alumina and magnesian basalts of the Neogene calc-alkaline series from the Eastern Sikhoteh-Alin are shown to have the following 87 Sr/ 86 Sr ratios: 0.70390-0.70465; 0.70347-0.70401, and the 0.70330-0.70347. Analysis of variations of Sr ratios, REE, HFSE, and LILE suggests that they are the products of successive melting of a multicomponent source containing the peridotite material of OIB- and MORB-types altered by fluids to a different degree and the pelagic sediments

  15. Mes chers collègues, les moines, ou le partage de l’ignorance

    Directory of Open Access Journals (Sweden)

    Laurence Caillet

    2009-03-01

    Full Text Available Mes chers collègues, les moines, ou le partage de l’ignorance. Aucun statut ne m’a autant étonnée que celui de collègue qui me fut conféré par les moines du Grand monastère de l’Est, à Nara. Après avoir testé mes connaissances en matière de rituel, ces moines fort savants manifestèrent en effet, avec ostentation, leur ignorance. Pointant pour moi des détails liturgiques qu’ils tenaient pour incompréhensibles, ils prirent un plaisir évident à bavarder histoire et théologie, comme si je pouvais apporter quoi que ce soit. Cette mise en scène du caractère incompréhensible du rituel soulignait le caractère ineffable de cérémonies jadis accomplies au ciel par des entités supérieures. Je fournissais prétexte à décrire la vanité de l’érudition face à l’accomplissement des mystères et aussi l’importance de cette érudition pour renouer avec un sens originel irrémédiablement inconnaissable.My dear colleagues the monks, or the sharing of ignorance. No status has ever surprised me as much as that of “colleague” conferred on me by the monks of the Great Eastern Monastery of Nara. After testing my knowledge of ritual, these very learned monks made great show of their ignorance. Drawing my attention to liturgical details that they held to be incomprehensible, they took obvious pleasure in chatting about history and theology, as if I were capable of making the slightest contribution. This staging of the impenetrable nature of the ritual highlighted the ineffable character of the ceremonies performed in heaven long ago by superior beings. I provided a convenient pretext for describing the vanity of erudition in the face of the accomplishment of the mysteries, and also the importance of this erudition for renewing an original, irreparably unknowable meaning.

  16. Phase equilibria in the system As2-O5 - SrO

    International Nuclear Information System (INIS)

    Kasenov, B.K.; Ashlyaeva, I.V.

    1993-01-01

    T-x phase state diagram of As 2 O 5 -SrO system was investigated by the methods of physicochemical analysis. It was established that incongruently melting Sr(AsO 3 ) 2 (t mel 900 deg C), Sr 2 As 2 O 4 (t mel = 1140 deg C), Sr 4 As 2 O 9 (t mel = 1390 deg C) and congruently melting at 1635 deg C Sr 3 (AsO 4 ) 2 formed in the system. Eutectic points were revealed in the system: As 2 O 5 -Sr(AsO 3 ) 2 (15.0 mol % SrO, 700 deg C) and Sr 3 (AsO 4 ) 2 -Sr 4 As 2 O 9 (78 mol % SrO, 1370 deg C)

  17. Low Thermal Conductivity of RE-Doped SrO(SrTiO3)1 Ruddlesden Popper Phase Bulk Materials Prepared by Molten Salt Method

    Science.gov (United States)

    Putri, Yulia Eka; Said, Suhana Mohd; Refinel, Refinel; Ohtaki, Michitaka; Syukri, Syukri

    2018-04-01

    The SrO(SrTiO3)1 (Sr2TiO4) Ruddlesden Popper (RP) phase is a natural superlattice comprising of alternately stacking perovskite-type SrTiO3 layers and rock salt SrO layers along the crystallographic c direction. This paper discusses the properties of the Sr2TiO4 and (La, Sm)-doped Sr2TiO4 RP phase synthesized via molten salt method, within the context of thermoelectric applications. A good thermoelectric material requires high electrical conductivity, high Seebeck coefficient and low thermal conductivity. All three conditions have the potential to be fulfilled by the Sr2TiO4 RP phase, in particular, the superlattice structure allows a higher degree of phonon scattering hence resulting in lowered thermal conductivity. In this work, the Sr2TiO4 RP phase is doped with Sm and La respectively, which allows injection of charge carriers, modification of its electronic structure for improvement of the Seebeck coefficient, and most significantly, reduction of thermal conductivity. The particles with submicron size allows excessive phonon scattering along the boundaries, thus reduces the thermal conductivity by fourfold. In particular, the Sm-doped sample exhibited even lower lattice thermal conductivity, which is believed to be due to the mismatch in the ionic radius of Sr and Sm. This finding is useful as a strategy to reduce thermal conductivity of Sr2TiO4 RP phase materials as thermoelectric candidates, by employing dopants of differing ionic radius.

  18. Preparation of highly stable zeolite-alginate foam composite for strontium(90Sr) removal from seawater and evaluation of Sr adsorption performance.

    Science.gov (United States)

    Hong, Hye-Jin; Kim, Byoung-Gyu; Ryu, Jungho; Park, In-Su; Chung, Kang-Sup; Lee, Sang Moon; Lee, Jin-Bae; Jeong, Hyeon Su; Kim, Hyunchul; Ryu, Taegong

    2018-01-01

    Alginate bead is a promising strontium (Sr) adsorbent in seawater, but highly concentrated Na ions caused over-swelling and damaged the hydrogel bead. To improve the mechanical stability of alginate bead, flexible foam-type zeolite-alginate composite was synthesized and Sr adsorption performance was evaluated in seawater; 1-10% zeolite immobilized alginate foams were prepared by freeze-dry technique. Immobilization of zeolite into alginate foam converted macro-pores to meso-pores which lead to more compact structure. It resulted in less swollen composite in seawater medium and exhibited highly improved mechanical stability compared with alginate bead. Besides, Sr adsorption efficiency and selectivity were enhanced by immobilization of zeolite in alginate foam due to the increase of Sr binding sites (zeolite). In particular, Sr selectivity against Na was highly improved. The 10% zeolite-alginate foam exhibited a higher log K d of 3.3, while the pure alginate foam exhibited 2.7 in the presence of 0.1 M Na. Finally, in the real seawater, the 10% zeolite-alginate foam exhibited 1.5 times higher Sr adsorption efficiency than the pure alginate foam. This result reveals that zeolite-alginate foam composite is appropriate material for Sr removal in seawater due to its swelling resistance as well as improved Sr adsorption performance in complex media. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Geographical traceability based on 87Sr/86Sr indicator: a first approach for PDO Lambrusco wines from Modena.

    Science.gov (United States)

    Durante, Caterina; Baschieri, Carlo; Bertacchini, Lucia; Cocchi, Marina; Sighinolfi, Simona; Silvestri, Michele; Marchetti, Andrea

    2013-12-01

    The main goal of this study was to evaluate (87)Sr/(86)Sr ratio in different matrices, namely soils, branches, and grape juices, of an oenological food chain in order to develop a robust analytical strategy able to link the investigated food to its territory of origin. The (87)Sr/(86)Sr has been used as traceability marker and several aspects, affected its variability, i.e. geological features of the investigated area, the bio-available fraction of elements in the soils and the up-take of the plant, have been taken into account. Optimisation of an analytical procedure for the separation of Sr from its interferences and investigation of the analytical performances in terms of precision of used methodology have been carried out as well. This work highlighted a good match between the isotopic values monitored in the bio-available fraction of soils and their respective grape juices for almost all the investigated areas. The correlation with food satisfyingly improves when isotopic relative abundance values of branches vine are considered. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. FEP report for the safety assessment SR-Can

    International Nuclear Information System (INIS)

    Skagius, Kristina

    2006-11-01

    This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Can, and forms an important part of the reporting of the project. The SR-Can project is a preparatory stage for the SR-Site assessment, and the report from that project will be used in support of SKB's application to build a final repository. The overall objective of the FEP analysis and processing included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The overall objective also extended to the development of procedures for such a systematic FEP analysis as well as the application of those procedures in order to establish an SR-Can FEP catalogue within the framework of the SKB FEP database. The work started by implementing the content of the SR 97 Process Report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs identified through the audit process were sorted into three main categories i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. This resulted in additions to the SR 97 list of processes and to the lists of initial state FEPs and external factors to be addressed in further processing. The further processing of the initial state FEPs revealed that those FEPs that are not covered by the

  1. The effect of secondary apatite on the initial 87Sr/86Sr ratio determination in granitic rocks: a case study of the Tadamigawa pluton, northeastern Japan

    Science.gov (United States)

    Wakasugi, Y.; Ichino, K.; Tanioka, Y.; Wakaki, S.; Tsuboi, M.; Ishikawa, T.

    2017-12-01

    Apatite is a major accessory mineral in igneous rocks. Because Rb contents in apatite are very low, 87Sr/86Sr ratios of magmatic apatite are useful to estimate the initial 87Sr/86Sr ratio (SrI) of igneous rocks. Secondary post-magmatic event such as hydrothermal alteration may also crystallize secondary apatite, which may inhibit the estimation of SrI of igneous rocks. In this study, we examine the effects of secondary apatite on the initial 87Sr/86Sr ratio determination of granitic rocks by using acid leaching technique. Leached apatite samples were first separated from the whole rock powder as a heavy mineral fraction by heavy liquid technique, and the heavy mineral fraction was then leached by 3 M HNO3. The isotopic ratios of Sr and the concentrations of Rb and Sr were analyzed by TIMS and ICP-MS at Kochi Core Center, respectively. The Tadamigawa Older-stage granites, which locate in the Taishaku Mountains at the northeastern part of Japan, intrude into the Ashio Jurassic complex, and the ages of these rocks are late Cretaceous to Paleogene. The U-Pb ages of zircon and the K-Ar ages of biotite for these rocks are c. 100 Ma [1, 2]. Rb-Sr whole-rock isochron age of the pluton is 96.5 ± 1.3 Ma (SrI = 0.70534 ± 0.00003) and it is concordant with other radiometric ages. Rb-Sr mineral isochron ages range from 84.4 to 97.3 Ma and these ages are relatively younger than the Rb-Sr whole-rock isochron age. The difference among radiometric ages may reflect the difference of the closure temperature in each isotopic system. The Tadamigawa Older-stage granites have SrI for Rb-Sr mineral isochron range from 0.7053 to 0.7061 and are very similar to that (0.70534) for Rb-Sr whole-rock isochron. These may suggest that the Tadamigawa Older-stage granites are generated from same parental magma. However, 87Sr/86Sr ratios of the leached apatite samples were 0.70544-0.70856 and are relatively higher than SrI obtained from the Rb-Sr mineral isochrons (0.7053-0.7061). This result

  2. The User Interface: The Point of Competition.

    Science.gov (United States)

    Tufte, Edward

    1992-01-01

    Discusses the importance of skillful visual design of computer screens and provides guidelines for screen design in the areas of information resolution, interaction of design elements, color, and typography and icons. (MES)

  3. A method for determination of 90Sr in vegetation

    International Nuclear Information System (INIS)

    Nygren, U.

    1998-12-01

    This report describes a method for determination of 90 Sr in vegetation. The method consists of wet-ashing the samples and separating Sr from the sample matrix by oxalate precipitation and extraction chromatography. 90 Y ingrowth is awaited after which Y is separated from Sr and 90 Y measured in a proportional counter. The method has been applied on two reference materials and the 90 Sr results agree well with the recommended values. The method has also been used on 20 samples of blueberry twigs and the mean recovery of Sr was 74%

  4. Migration and distribution of 90Sr in soil

    International Nuclear Information System (INIS)

    Yang Juncheng; Zhu Yongyi; Chen Jingjian

    1993-01-01

    The migration and distribution of radionuclide 90 Sr were conducted by the analysis of 97 soil longitudinal sections under natural conditions and by pot experiments with fallout and 90 Sr solution, respectively. Spring wheat and rice were employed in the pot experiments. The result showed that the radionuclide 90 Sr was mainly accumulated in the topsoil 0-10 cm under both of the natural and laboratory conditions. The vertical distribution of 90 Sr in soil agreed with the power function, which obtained was Y = 75.78 X -0.527 ; r = -0.986; n = 97. The existing forms of 90 Sr from fallout in soil, only 0.02-0.03% was in a soluble form and 0.06-0.07% in non-replaceable form

  5. OpenNebula KVM SR-IOV driver

    CSIR Research Space (South Africa)

    Macleod, D

    2013-05-01

    Full Text Available With the recent release of an OFED which supports SR-IOV on Infiniband HCAs it is now possible to use verbs from inside a VM. This VMM driver supports these Infiniband HCAs, and any other SR-IOV network device, in OpenNebula....

  6. Abscisic Acid (ABA) Regulation of Arabidopsis SR Protein Gene Expression

    Science.gov (United States)

    Cruz, Tiago M. D.; Carvalho, Raquel F.; Richardson, Dale N.; Duque, Paula

    2014-01-01

    Serine/arginine-rich (SR) proteins are major modulators of alternative splicing, a key generator of proteomic diversity and flexible means of regulating gene expression likely to be crucial in plant environmental responses. Indeed, mounting evidence implicates splicing factors in signal transduction of the abscisic acid (ABA) phytohormone, which plays pivotal roles in the response to various abiotic stresses. Using real-time RT-qPCR, we analyzed total steady-state transcript levels of the 18 SR and two SR-like genes from Arabidopsis thaliana in seedlings treated with ABA and in genetic backgrounds with altered expression of the ABA-biosynthesis ABA2 and the ABA-signaling ABI1 and ABI4 genes. We also searched for ABA-responsive cis elements in the upstream regions of the 20 genes. We found that members of the plant-specific SC35-Like (SCL) Arabidopsis SR protein subfamily are distinctively responsive to exogenous ABA, while the expression of seven SR and SR-related genes is affected by alterations in key components of the ABA pathway. Finally, despite pervasiveness of established ABA-responsive promoter elements in Arabidopsis SR and SR-like genes, their expression is likely governed by additional, yet unidentified cis-acting elements. Overall, this study pinpoints SR34, SR34b, SCL30a, SCL28, SCL33, RS40, SR45 and SR45a as promising candidates for involvement in ABA-mediated stress responses. PMID:25268622

  7. SR-71 Pilot Stephen (Steve) D. Ishmael

    Science.gov (United States)

    1992-01-01

    NASA research pilot Stephen D. Ishmael is pictured here in front of an SR-71 Blackbird on the ramp at the Dryden Flight Research Center, Edwards, California. Ishmael was one of two NASA research pilots assigned to the SR-71 high speed research program in the early 1990s at NASA's Dryden Flight Research Facility (redesignated the Dryden Flight Research Center in 1994), Edwards, California. Ishmael became a NASA research pilot in 1977. Data from the SR-71 program will be used to aid designers of future supersonic aircraft and propulsion systems. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and

  8. (Ba+Sr)/Ti ratio dependence of the dielectric properties for (Ba0.5Sr0.5)TiO3 thin films prepared by ion beam sputtering

    Science.gov (United States)

    Yamamichi, Shintaro; Yabuta, Hisato; Sakuma, Toshiyuki; Miyasaka, Yoichi

    1994-03-01

    (Ba0.5Sr0.5)TiO3 thin films were prepared by ion beam sputtering from powder targets with (Ba+Sr)/Ti ratios ranging from 0.80 to 1.50. All of the perovskite (Ba,Sr)TiO3 films were single phase except for the film with a (Ba+Sr)/Ti ratio of 1.41. The dielectric constant values notably depended on the (Ba+Sr)/Ti ratio for films thicker than 70 nm. The highest dielectric constant of 580 was achieved for the 5% (Ba+Sr) rich film. This (Ba+Sr)/Ti ratio dependence was diminished by the thickness dependence for thinner films. The grain sizes for the 9% (Ba+Sr) rich film and for the 6% (Ba+Sr) poor film ranged from 70 to 100 nm and from 30 to 60 nm, respectively. This grain size difference could explain why slightly A-site rich (Ba,Sr)TiO3 films have a larger dielectric constant than A-site poor films.

  9. Sr and Nd isotope systematics in fish teeth

    International Nuclear Information System (INIS)

    Staudigel, H.; Zindler, A.

    1985-01-01

    High concentrations of Sr and Nd in fish teeth apatite (up to 2000 and 3800 ppm, respectively) make them relatively impervious to diagenetic overprints and allow high-precision analysis of 87 Sr/ 86 Sr and 143 Nd/ 144 Nd of very small amounts of material. 87 Sr/ 86 Sr ratios of 14 Cenozoic samples ( 87 Sr/ 86 Sr stratigraphic dating. A compilation of published 143 Nd/ 144 Nd data from recent Mn-nodules and marine Fe/Mn deposits shows that the North-Central Pacific Ocean and the major portion of the Atlantic Ocean display distinctly different, narrow ranges in isotopic compositions. Between these two areas, the 143 Nd/ 144 Nd of Mn-nodules vary systematically towards intermediate compositions in the Southern Oceans, reflecting the communication between the Atlantic and Pacific Oceans through the eastward moving Antarctic Circumpolar Current. The 143 Nd/ 144 Nd of the 2-55 Ma old fish teeth analyzed are typically close to the range of 143 Nd/ 144 Nd in Recent Mn-nodules and seawater for the respective ocean and, thus, indicate no significant change through this time period. The 143 Nd/ 144 Nd of fish teeth from the North Pacific Ocean are highest during periods of high aeolian sedimentation. (orig.)

  10. ESTRATEGIA INTEGRAL PARA PyMES INNOVADORAS

    Directory of Open Access Journals (Sweden)

    Jairo Sanchez Quintero

    2003-07-01

    Full Text Available La administración y la planeación prospectivas, La planeación estratégica y la logística englobanlas necesidades de direccionamiento estratégico de las empresas a nivel mundial. Estos tres elementos  actúan como un trípode. Es decir, si falta uno de ellos no podrá haber estabilidad. La prospectiva aporta el análisis y construcción de escenarios futuros además del análisis de actores. La planeación estratégica (unida a la prospectiva permite el análisis de las variables internas y externas para formular los propósitos (misión, visión, objetivos y metas, las estrategias, los planes de acción y los indicadores de desempeño y logro, tanto para la empresa en su totalidad como para cada área de la misma en particular. Finalmente, la logística permite agregar valor e integrar los procesos transversales de la empresa, ya que se ocupa del mejoramiento de actividades desde la compra de materias primas o insumos hasta la distribución y el servicio al cliente en actividades de postventa. En este artículo, se presentan los hallazgos centrales de la investigación exploratoria sobre planeación prospectiva, estratégica y logística. Dicho estudio se concentra en una muestra de 29 empresas del sector de alimentos de Bogotá (19 empresas de lácteos y 10 de conservas y aplican una metodología de estudio de caso e Investigación y acción a cuatro empresas. El análisis de esta muestra empresarial y la revisión Bibliográfica realizada sentaron las bases para el diseño de la guía y la herramienta de mejora continua en estrategia, que forma parte de la caja de herramientas, fruto del trabajo del grupo PyMES, EAN durante el último año.

  11. Tracing sediment sources in upstream agricultural catchments: contribution of elemental geochemistry, 87Sr/86Sr ratio and radionuclides measurements

    International Nuclear Information System (INIS)

    Le-Gall, Marion

    2016-01-01

    Soil erosion is recognized as one of the main processes of land degradation in agricultural environments. This study develops an original fingerprinting method to examine sediment source contributions in two contrasted agricultural catchments. Several properties were used to trace sediment lithological sources ( 87 Sr/ 86 Sr ratios, elemental concentrations), soil surface and subsurface sources ( 137 Cs) and to quantify their temporal dynamics ( 7 Be, 210 Pb xs ). In the Louroux catchment (24 km 2 , France), representative of drained areas of Northwestern Europe, results showed the dominant contribution of very fine particles (≤2 μm) transiting through the tile drainage system to suspended sediment. Sediment accumulated in the river channel was mainly exported during the two first floods investigated in 2013 whereas the next event was characterized by the transport of sediment eroded from the cultivated soil surface. Mixing models were used, and results indicated that surface sources contributed the majority of sediment deposited in the pond, at the outlet of the catchment. The two lithological sources, discriminated using 87 Sr/ 86 Sr ratios, contributed in similar proportions to downstream pond sediment. In contrast, significant variations were observed since the 1950's. These changes may be related to the progressive implementation of land consolidation schemes within the catchment. Results obtained in the Louroux catchment revealed the potential of 87 Sr/ 86 Sr ratios to trace sediment lithological sources. The methodology was then applied to the larger and steeper Guapore catchment (2000 km 2 , Brazil), exposed to a more erosive climate and characterized by contrasted laterite soils. 87 Sr/ 86 Sr ratios and elements that discriminated the five soil types found in the catchment were incorporated in mixing models. Results showed that the major part of sediment was supplied by soils located in lower catchment parts. This result suggests the higher

  12. Kinetics of distribution of 90Sr in Beijing-white layers

    International Nuclear Information System (INIS)

    Shang Zhaorong; Xu Shiming; Zhao Wenhu; Hou Lanxin

    1993-08-01

    The experiment feeding 90 Sr(NO 3 ) 2 in the range of 1.85 x 10 2 to 1.85 x 10 5 Bq/chicken was carried out with 45 Beijing-white layers to observe the regular pattern of absorption and distribution of 90 Sr in organs and tissues. The results are summarized as follows: the uptake rate of 90 Sr by layer through oral feeding is very low. Most part of 90 Sr drains away from body with daily excreta and egg. The accumulation of 90 Sr in the body is low and about 70% is in the bone. About 99% of 90 Sr in egg is concentrated in the eggshell. The order of absorptivity of 90 Sr in tissues is bone>feather>muscle>blood>viscera. The absorption coefficient of 90 Sr in organs and tissues in different stages with different feeding volumes has been calculated

  13. The accumulation and elimination of 89Sr in tea leaves

    International Nuclear Information System (INIS)

    Zhang Yongxi; Wang Shouxiang; Chen Chuanqun; Sun Zhiming; Hu Bingmin; Huang Dan

    1995-01-01

    The 89 Sr was added to the tea tree-soil system by different ways. The 89 Sr in the system through the over-ground part of tea tree, was much more than that through soil. The 89 Sr concentration in older leaves was higher than in shoot for a definite treatment. The accumulation elimination law of 89 Sr in leaves varied with the treatments. For the treatment through the over-ground part, the 89 Sr concentration in older leaves and shoot was monotonously decreased with time increasing. But for the treatment through soil the 89 Sr concentration in shoot was increased to reach a peak value, and then decreased slowly; while the 89 Sr concentration in older leaves increased quickly in a period, then increased slowly to attain a saturated value. In addition, the concentration factor of 89 Sr in older leaves and shoot were determined

  14. Interim FEP report for the safety assessment SR-Can

    Energy Technology Data Exchange (ETDEWEB)

    Skagius, Kristina (ed.) [Kemakta Konsult AB, Stockholm (Sweden)

    2004-08-01

    This report describes the work with identification and structuring of features, events and processes (FEPs) that has been carried out within the scope of the SR-Can safety assessment up to the time of the interim reporting of the project. The overall objective of the work is to develop a database of features, events and processes in a format that would facilitate both a systematic analysis of FEPs and documentation of the FEP analysis as well as facilitate revisions and updates to be made in connection with new safety assessments. This overall objective also includes the development of procedures for a systematic FEP analysis as well as to apply these procedures in order to arrive at an SR-Can version of the FEP database. The work started by implementing the content of the SR 97 Process report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs from the audit were sorted into three main categories in the SR-Can database i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. These groups of FEPs were further processed for making decisions on how to handle these FEPs in the assessment. Biosphere processes were not included in the SR 97 Process report and there is thus not the same basis for updating these descriptions as for the engineered barriers and the geosphere. All biosphere FEPs from the audit have therefore been compiled in a single category in the database, but remain to be further handled. FEPs were also categorised as irrelevant or as being related to methodology on a general

  15. Interim FEP report for the safety assessment SR-Can

    International Nuclear Information System (INIS)

    Skagius, Kristina

    2004-08-01

    This report describes the work with identification and structuring of features, events and processes (FEPs) that has been carried out within the scope of the SR-Can safety assessment up to the time of the interim reporting of the project. The overall objective of the work is to develop a database of features, events and processes in a format that would facilitate both a systematic analysis of FEPs and documentation of the FEP analysis as well as facilitate revisions and updates to be made in connection with new safety assessments. This overall objective also includes the development of procedures for a systematic FEP analysis as well as to apply these procedures in order to arrive at an SR-Can version of the FEP database. The work started by implementing the content of the SR 97 Process report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs from the audit were sorted into three main categories in the SR-Can database i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. These groups of FEPs were further processed for making decisions on how to handle these FEPs in the assessment. Biosphere processes were not included in the SR 97 Process report and there is thus not the same basis for updating these descriptions as for the engineered barriers and the geosphere. All biosphere FEPs from the audit have therefore been compiled in a single category in the database, but remain to be further handled. FEPs were also categorised as irrelevant or as being related to methodology on a general

  16. Igneous Consequence Modeling for the TSPA-SR

    International Nuclear Information System (INIS)

    McCord, John

    2001-01-01

    The purpose of this technical report is to develop credible, defendable, substantiated models for the consequences of igneous activity for the TSPA-SR Model. The effort will build on the TSPA-VA and improve the quality of scenarios and depth of the technical basis underlying disruptive events modeling. Computational models for both volcanic eruptive releases (this is an event that results in ash containing waste being ejected from Yucca Mountain) and igneous intrusion groundwater releases (this is an event that reaches the repository level, impacts the waste packages, and produces releases from waste packages damaged by igneous activity) will be included directly in the TSPA calculations as part of the TSPA-SR Model. This Analysis Model Report (AMR) is limited to development of the conceptual models for these two scenarios. The mathematical implementation of these conceptual models will be done within the TSPA-SR Model. Thus, this AMR will not include any model results or sensitivity analyses. Calculation of any doses resulting from igneous releases will also be done within the TSPA-SR model, as will the probabilistic weighting of these doses. Calculation and analysis of the TSPA-SR Model results for igneous disruption are, therefore, outside the scope of this activity. The reason for not running the mathematical models as part of this AMR is that the models are integrated within the TSPA-SR model and, thus, any model simulations and the corresponding results are out of the scope of this AMR. The scope of this work as defined in the development plan (CRWMS M and O 2000j) involves using data that has been extracted from existing sources to design and support the TSPA-SR models for the transport of radionuclides following igneous disruption of the repository. The development plan states ''applications of the code in this analysis will be limited to testing of the code and sensitivity analyses during analysis design.'' In contrast to the development plan, the ASHPLUME

  17. Separation of 90Sr from Purex high level waste and development of a 90Sr-90Y generator

    International Nuclear Information System (INIS)

    Ramanujam, A.; Dhami, P.S.; Chitnis, R.R.; Achuthan, P.V.; Kannan, R.; Gopalakrishnan, V.; Balu, K.

    2000-04-01

    90 Y (T 1/2 =64.2 h) finds several applications in nuclear medicine. It is formed from the decay of 90 Sr which has a long half-life of 28.8 years. 90 Sr can be used as a long-lasting source for the production of carrier-free 90 Y. 90 Sr itself is abundantly available in high level waste (HLW) of PUREX origin. The present studies deal with the separation of pure 90 Sr from HLW and the subsequent separation of 90 Y from 90 Sr. Actinides and some of the fission products like lanthanides, zirconium, molybdenum and cesium were first removed from the HLW using methods based on solvent extraction and ion-exchange studied earlier in our laboratory. The resulting waste solution was used as a feed for the present process. The separation of 90 Sr from HLW was based on radiochemical method which involved a repeated scavenging with ferric hydroxide followed by strontium carbonate precipitation. The separation of 90 Y from 90 Sr was achieved by membrane separation technique. A compact generator is developed for this separation using a commercially available polytetrafluoroethylene (PTFE) membrane, impregnated with indigenously synthesised 2-ethylhexyl 2-ethylhexyl phosphonic acid (KSM-17). Generator system overcomes the drawbacks associated with conventional solvent extraction and ion-exchange based generators. The product is in chloride form and is suitable for complexation studies. After gaining an operating experience of ∼3 years in generating carrier-free 90 Y at 2 mCi level for initial studies in radiotherapeutic applications, the process was scaled up for the production of about 12 mCi of 90 Y to be used for animal studies before its application to patients. Radiochemical and chemical purity of the product was critically assayed by radiometry, ICP-AES, etc. The process is amenable for further scaling up. (author)

  18. FEP report for the safety assessment SR-Can

    Energy Technology Data Exchange (ETDEWEB)

    Skagius, Kristina [Kemakta Konsult AB, Stockholm (Sweden)

    2006-11-15

    This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Can, and forms an important part of the reporting of the project. The SR-Can project is a preparatory stage for the SR-Site assessment, and the report from that project will be used in support of SKB's application to build a final repository. The overall objective of the FEP analysis and processing included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The overall objective also extended to the development of procedures for such a systematic FEP analysis as well as the application of those procedures in order to establish an SR-Can FEP catalogue within the framework of the SKB FEP database. The work started by implementing the content of the SR 97 Process Report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs identified through the audit process were sorted into three main categories i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. This resulted in additions to the SR 97 list of processes and to the lists of initial state FEPs and external factors to be addressed in further processing. The further processing of the initial state FEPs revealed that those FEPs that are not covered by the

  19. Comparative study of potentially J{sub eff} = 0 ground state iridium(V) in SrLaNiIrO{sub 6}, SrLaMgIrO{sub 6}, and SrLaZnIrO{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, Klaus K.; Agrestini, Stefano; Tjeng, Liu Hao [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Tanaka, Arata [Department of Quantum Matter, AdSM, Hiroshima University, Higashi-Hiroshima (Japan); Jansen, Martin [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Max Planck Institute for Solid State Research, Stuttgart (Germany)

    2017-12-13

    A series of polycrystalline double perovskites SrLaBIrO{sub 6} (B = Ni, Mg, Zn) containing Ir{sup 5+} (5d{sup 4}) was synthesized by solid state reactions, and structural, magnetic and electronic properties were investigated. The isotypic fully ordered double perovskites crystallize in space group P2{sub 1}/n and show semiconducting behavior with estimated bandgaps of approximately 0.2 eV for SrLaNiIrO{sub 6} and SrLaZnIrO{sub 6}, and 0.4 eV for SrLaMgIrO{sub 6}. SrLaNiIrO{sub 6} is an antiferromagnet with a Neel temperature of 74 K (μ{sub eff} = 3.3 μ{sub B}, θ{sub W} = -90 K), whereas SrLaMgIrO{sub 6} and SrLaZnIrO{sub 6} are weakly paramagnetic. All title compounds exhibit a temperature-independent contribution to the measured magnetic susceptibility, which supports the notion for a van-Vleck-type response originating from the Ir{sup 5+} (5d{sup 4}, J{sub eff} = 0) ions. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. System of Sr(NO sub 2 ) sub 2 -Sr(OH) sub 2 -H sub 2 O at 25 deg C. Sistema Sr(NO sub 2 ) sub 2 -H sub 2 O pri 25 grad C

    Energy Technology Data Exchange (ETDEWEB)

    Popova, T B; Berdyukova, V A; Khutsistova, F M [Kalmytskij Gosudarstvennyj Univ., Ehlista (USSR) Rostovskij-na-Donu Gosudarstvennyj Univ., Rostov-na-Donu (USSR)

    1990-02-01

    Sr(NO{sub 2}){sub 2}-Sr(OH){sub 2}-H{sub 2}O system was investigated by the methods of solubility, density, viscosity, electric conductivity and refractometry. It was established that its compoments form the compound 4Sr(NO{sub 2}){sub 2}xSr(OH){sub 2}x8H{sub 2}O. The compound was separated from solution; its density, decomposition temperature were determined; IR spectra and X-ray patterns of prepared and initial compounds were obtained.

  1. ELNES study of chemical solution deposited SrO(SrTiO3)n Ruddlesden-Popper films: Experiment and simulation

    International Nuclear Information System (INIS)

    Riedl, T.; Gemming, T.; Weissbach, T.; Seifert, G.; Gutmann, E.; Zschornak, M.; Meyer, D.C.; Gemming, S.

    2009-01-01

    This article analyzes electron energy-loss near-edge fine structures of the SrO(SrTiO 3 ) n=1 Ruddlesden-Popper system and of the parent compounds SrTiO 3 and SrO by comparison with first principles calculations. For that, the fine structures of chemical solution deposited Ruddlesden-Popper films have been experimentally recorded by means of transmission electron microscopy. Moreover, density of states computations using an all-electron density-functional code have been performed. It is shown that the appearance and shape of the experimental O-K and Ti-L 2,3 fine structure features result from the crystallography-dependent electronic structure of the investigated oxides, which display technologically interesting dielectric as well as lattice-structural properties.

  2. Development of 90Sr-90Y generators

    International Nuclear Information System (INIS)

    Barrio, Graciela

    2007-01-01

    Yttrium-90 is a radioisotope of great interest in the field of Nuclear Medicine. It is considered one of the most important and most used radionuclides for radioimmunotherapeutical applications, especially promising for the treatment of certain types of cancer. Another important application of 90 Y is radio synovectomy. This radionuclide has a half-life of 64 hours, emits long range beta particles (maximum energy of 2.3 MeV) and decays, without intermediate nuclides, to a stable daughter. 90 Y may be obtained carrier-free, generated by the decay of its parent 90 Sr (half-life=28 years). 90 Sr is a product from uranium fission, and due to its long half-life, can be indefinitely used, which is certainly advantageous. It is present in great amounts, and needs to be processed and purified in order to be used as raw material for the generators. Generators of 90 Sr- 90 Y may thus be used during various months, due to 90 Sr long half-life. Several methods for the separation of 90 Y from 90 Sr by solvent extraction and ion exchange have been reported in literature. Thanks to its simplicity, ion exchange techniques have been more commonly used for this generator system. The main objective of this work was to develop a methodology for the preparation of 90 Sr- 90 Y generators, using cationic exchange resins. In such method, 90 Sr is strongly adsorbed in the resin and 90 Y is eluted by a 0.003 M EDTA solution. According to the quality control carried out, results showed that elution yields are greater than 65%, thus confirming the efficiency of the separation method used.

  3. Possible two-stage 87Sr evolution in the Stockdale Rhyolite

    International Nuclear Information System (INIS)

    Compston, W.; McDougall, I.; Wyborn, D.

    1982-01-01

    The Rb-Sr total-rock data for the Stockdale Rhyolite, of significance for the Palaeozoic time scale, are more scattered about a single-stage isochron than expected from experimental error. Two-stage 87 Sr evolution for several of the samples is explored to explain this, as an alternative to variation in the initial 87 Sr/ 86 Sr which is customarily used in single-stage dating models. The deletion of certain samples having very high Rb/Sr removes most of the excess scatter and leads to an estimate of 430 +- 7 m.y. for the age of extrusion. There is a younger alignment of Rb-Sr data within each sampling site at 412 +- 7 m.y. We suggest that the Stockdale Rhyolite is at least 430 m.y. old, that its original range in Rb/Sr was smaller than now observed, and that it experienced a net loss in Sr during later hydrothermal alteration at ca. 412 m.y. (orig.)

  4. Determination of the electrostatic potential distribution in Pt/Fe:SrTiO3/Nb:SrTiO3 thin-film structures by electron holography

    Science.gov (United States)

    Marchewka, Astrid; Cooper, David; Lenser, Christian; Menzel, Stephan; Du, Hongchu; Dittmann, Regina; Dunin-Borkowski, Rafal E.; Waser, Rainer

    2014-11-01

    We determined the electrostatic potential distribution in pristine Pt/Fe:SrTiO3/Nb:SrTiO3 structures by electron holography experiments, revealing the existence of a depletion layer extending into the Nb-doped bottom electrode. Simulations of potential profiles in metal-insulator-metal structures were conducted assuming different types and distributions of dopants. It is found that the presence of acceptor-type dopant concentrations at the Fe:SrTiO3/Nb:SrTiO3 interface with a donor-doped insulating layer provides a good match to the measured profile. Such acceptor-type interface concentrations may be associated with Sr vacancies on the Nb:SrTiO3 side of the bottom interface.

  5. Assessing Covariation of Holocene Monsoon Intensity and Local Moisture Conditions in Eastern and Southwestern Amazon Basin Using Speleothem δ18O and 87Sr/86Sr Values

    Science.gov (United States)

    Ward, B. M.; Wong, C. I.; Novello, V. F.; Silva, L.; McGee, D.; Cheng, H.; Wang, X.; Edwards, R. L.; Cruz, F. W., Sr.; Santos, R. V.

    2017-12-01

    δ18O records from South America offer insight into past variability of the South American Monsoon System (SAMS). Potential, however, for understanding local moisture conditions is limited as precipitation δ18O is strongly influenced by regional climate dynamics. Here we create Holocene speleothem 87Sr/86Sr records at 200-yr resolution using TIMS methods in the Center for Isotope Geochemistry at Boston College to complement existing Holocene δ18O speleothem records and investigate local moisture conditions above caves located in the eastern Amazon Basin (PAR - 4°S, 55°W) and southwestern Brazil (JAR - 21°S, 56°W). Speleothem 87Sr/86Sr variability is interpreted to reflect differences in the extent of water-rock interaction due to differences in infiltration rates under wet and dry conditions. Drier conditions promote longer residence time, enhanced water-rock interaction, and greater evolution of dripwater 87Sr/86Sr values from an initial isotopic signature acquired from the soil to the signature of the cave host rock. PAR speleothem 87Sr/86Sr values range from 0.71024 to 0.71067 and are bracketed by soil (0.71710 to 0.70956) and bedrock (0.70852 to 0.70899) values. JAR speleothem 87Sr/86Sr values range from 0.71216 to 0.71539 and are greater than bedrock values (0.70825 to 0.71219), although some speleothem values exceed the single analysis conducted of the soil isotopic composition (0.71473). JAR speleothem 87Sr/86Sr values increase from the early to mid Holocene, consistent with increase in local moisture availability associated with intensification of the SAMS suggested by decreasing δ18O values in many records from the region. Speleothem 87Sr/86Sr values at JAR decrease from the mid to late Holocene, consistent with an increase in δ18O values at PAR that suggest a decline in monsoon intensity. 87Sr/86Sr variability at JAR, however, is positively correlated with the δ18O record. Preliminary 87Sr/86Sr results from PAR are only broadly consistent with

  6. Investigation of He–W interactions using DiMES on DIII-D

    International Nuclear Information System (INIS)

    Doerner, R P; Rudakov, D L; Chrobak, C P; Pace, D C; Briesemeister, A R; Corr, C; Kluth, P; Thompson, M; De Temmerman, G; Pitts, R A; Lasnier, C J; McLean, A G; Schmitz, O; Winters, V

    2016-01-01

    Tungsten button samples were exposed to He ELMing H-mode plasma in DIII-D using 2.3 MW of electron cyclotron heating power. Prior to the exposures, the W buttons were exposed to either He, or D, plasma in PISCES-A for 2000 s at surface temperatures of 225–850 °C to create a variety of surfaces (surface blisters, subsurface nano-bubbles, fuzz). Erosion was spectroscopically measured from each DiMES sample, with the exception of the fuzzy W samples which showed almost undetectable WI emission. Post-exposure grazing incidence small angle x-ray scattering surface analysis showed the formation of 1.5 nm diameter He bubbles in the surface of W buttons after only a single DIII-D (3 s, ∼150 ELMs) discharge, similar to the bubble layer resulting from the 2000 s. exposure in PISCES-A. No surface roughening, or damage, was detected on the samples after approximately 600 ELMs with energy density between 0.04–0.1 MJ m −2 . (paper)

  7. ACTH Regulation of Adrenal SR-B1

    Directory of Open Access Journals (Sweden)

    Wen-Jun eShen

    2016-05-01

    Full Text Available The adrenal gland is one of the prominent sites for steroid hormone synthesis. Lipoprotein-derived cholesterol esters delivered via scavenger receptor, class B type 1 (SR-B1 constitute the dominant source of cholesterol for steroidogenesis, particularly in rodents. ACTH stimulates steroidogenesis through downstream actions on multiple components involved in steroidogenesis. Both acute and chronic ACTH treatment can modulate SR-B1 function including its transcription, its post transcriptional stability, its phosphorylation and dimerization status, as well as its interaction with other protein partners; all of which result in changes in the ability of SR-B1 to mediate HDL-cholesterol ester uptake and the supply of cholesterol for conversion to steroids. Here we provide a review of the recent findings on the regulation of adrenal SR-B1 function by ACTH.

  8. Rapid determination of {sup 90}Sr in urine samples using AnaLig Sr-01

    Energy Technology Data Exchange (ETDEWEB)

    Bilohuscin, J.; Dulanska, S.; Gardonova, V. [Univerzita Komenskeho, Prirodovedecka fakulta, Katedra jadrovej chemie, 84215 Bratislava (Slovakia)

    2013-04-16

    This work describes the use of IBC's AnaLig Sr-01 molecular recognition technology product to effectively and selectively pre-concentrate, separate and recover strontium from urine samples. This method uses two-stage columns separation consisting of two different commercial products Eichrom's Pre-filter Material and AnaLig Sr-01 column from IBC Advanced Technologies. This method does not involve co-precipitation of strontium as phosphates and oxalates from urine samples. The new rapid method separates strontium-90 with high chemical recovery (authors)

  9. Development of an on-line flow injection Sr/matrix separation method for accurate, high-throughput determination of Sr isotope ratios by multiple collector-inductively coupled plasma-mass spectrometry.

    Science.gov (United States)

    Galler, Patrick; Limbeck, Andreas; Boulyga, Sergei F; Stingeder, Gerhard; Hirata, Takafumi; Prohaska, Thomas

    2007-07-01

    This work introduces a newly developed on-line flow injection (FI) Sr/Rb separation method as an alternative to the common, manual Sr/matrix batch separation procedure, since total analysis time is often limited by sample preparation despite the fast rate of data acquisition possible by inductively coupled plasma-mass spectrometers (ICPMS). Separation columns containing approximately 100 muL of Sr-specific resin were used for on-line FI Sr/matrix separation with subsequent determination of (87)Sr/(86)Sr isotope ratios by multiple collector ICPMS. The occurrence of memory effects exhibited by the Sr-specific resin, a major restriction to the repetitive use of this costly material, could successfully be overcome. The method was fully validated by means of certified reference materials. A set of two biological and six geological Sr- and Rb-bearing samples was successfully characterized for its (87)Sr/(86)Sr isotope ratios with precisions of 0.01-0.04% 2 RSD (n = 5-10). Based on our measurements we suggest (87)Sr/(86)Sr isotope ratios of 0.713 15 +/- 0.000 16 (2 SD) and 0.709 31 +/- 0.000 06 (2 SD) for the NIST SRM 1400 bone ash and the NIST SRM 1486 bone meal, respectively. Measured (87)Sr/(86)Sr isotope ratios for five basalt samples are in excellent agreement with published data with deviations from the published value ranging from 0 to 0.03%. A mica sample with a Rb/Sr ratio of approximately 1 was successfully characterized for its (87)Sr/(86)Sr isotope signature to be 0.718 24 +/- 0.000 29 (2 SD) by the proposed method. Synthetic samples with Rb/Sr ratios of up to 10/1 could successfully be measured without significant interferences on mass 87, which would otherwise bias the accuracy and uncertainty of the obtained data.

  10. Effect of Flowing Water on Sr Sorption Changes of Hydrous Sodium Titanate

    Directory of Open Access Journals (Sweden)

    Youko Takahatake

    2017-12-01

    Full Text Available Radioactive contaminated water has been generated at the Fukushima Daiichi Nuclear Power station (F1NPS. Hydrous sodium titanate (SrTreat® is able to remove radioactive Strontium (Sr from this water. Knowing the amount of radioactive nuclides in the used as-received SrTreat® is important for effective disposal and deposition of the F1NPS waste. This study investigated changes in the ability of SrTreat® to sorb Sr, and to understand the causes of changes in the sorbing. An investigation of the Sr sorption ability of SrTreat® is important for calculating the initial radioactive inventory of used SrTreat®. This study carries out Sr sorption studies with acid-base titrations and X-ray photoelectron spectroscopy (XPS to characterize the properties. After exposure to simulated treated water for 99 h, the surface structure of the SrTreat® was changed, and the percentage of sorbed Sr and the buffer capacity for protons decreased. When the amount of radioactive nuclides contained in the used SrTreat® is calculated from the sorption data of the as-received SrTreat®, the radioactive Sr content will be overestimated with a concomitant increase in the deposition and disposal costs of the used SrTreat®.

  11. Principales prácticas de recursos humanos de las PyMEs industriales exitosas.

    Directory of Open Access Journals (Sweden)

    Liliana Rocío López Suárez

    2013-04-01

    Full Text Available El éxito competitivo de la PyME depende en parte de la buena gestión de recursos humanos,por lo que no darle el valor que requiere constituye una de las principales causas de fracasode estas empresas. La responsabilidad de la gestión eficaz de los recursos humanos recae fundamentalmenteen los directivos. La presente investigación tiene como objetivo identificarlos estilos de dirección y las principales prácticas de recursos humanos que llevan a cabo lasPyMEs industriales exitosas de México y España. Para alcanzar los objetivos antes reseñados,se ha realizado un análisis documental, así como entrevistas en profundidad a expertosen el área de recursos humanos. En este trabajo se presentan los principales resultados conrespecto a las prácticas mencionadas.

  12. [Mes differ by positioning: empirical testing of decentralized dynamics of the self].

    Science.gov (United States)

    Mizokami, Shinichi

    2013-10-01

    The present study empirically tested the conceptualization of the decentralized dynamics of the self proposed by Hermans & Kempen (1993), which they developed theoretically and from clinical cases, not from large samples of empirical data. They posited that worldviews and images of the self could vary by positioning even in the same individual, and denied that the ego was an omniscient entity that knew and controlled all aspects of the self (centralized ego). Study 1 tested their conceptualization empirically with 47 university students in an experimental group and 17 as a control group. The results showed that the scores on the Rosenberg's self-esteem scale and images of the Mes in the experimental group significantly varied by positioning, but those in the control group did not. Similar results were found in Study 2 with a sample of 120 university students. These results empirically supported the conceptualization of the decentralized dynamics of the self.

  13. Sr-containing hydroxyapatite: morphologies of HA crystals and bioactivity on osteoblast cells

    Energy Technology Data Exchange (ETDEWEB)

    Aina, Valentina [Department of Chemistry, Università degli Studi di Torino, Via P. Giuria 7, 10125 Torino (Italy); Centre of Excellence NIS (Nanostructured Interfaces and Surface) Università degli Studi di Torino (Italy); INSTM (Italian National Consortium for Materials Science and Technology), UdR Università di Torino (Italy); Bergandi, Loredana, E-mail: loredana.bergandi@unito.it [Department of Oncology, Università degli Studi di Torino, Via Santena 5/bis, 10126 Torino (Italy); Lusvardi, Gigliola; Malavasi, Gianluca [Department of Chemical and Geological Sciences, Università di Modena and Reggio Emilia, Via Campi 183, 41125 Modena (Italy); Imrie, Flora E.; Gibson, Iain R. [School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD (United Kingdom); Cerrato, Giuseppina [Department of Chemistry, Università degli Studi di Torino, Via P. Giuria 7, 10125 Torino (Italy); Centre of Excellence NIS (Nanostructured Interfaces and Surface) Università degli Studi di Torino (Italy); INSTM (Italian National Consortium for Materials Science and Technology), UdR Università di Torino (Italy); Ghigo, Dario [Department of Oncology, Università degli Studi di Torino, Via Santena 5/bis, 10126 Torino (Italy)

    2013-04-01

    A series of Sr-substituted hydroxyapatites (HA), of general formula Ca{sub (10−x)}Sr{sub x}(PO{sub 4}){sub 6}(OH){sub 2}, where x = 2 and 4, were synthesized by solid state methods and characterized extensively. The reactivity of these materials in cell culture medium was evaluated, and the behavior towards MG-63 osteoblast cells (in terms of cytotoxicity and proliferation assays) was studied. Future in vivo studies will give further insights into the behavior of the materials. A paper by Lagergren et al. (1975), concerning Sr-substituted HA prepared by a solid state method, reports that the presence of Sr in the apatite composition strongly influences the apatite diffraction patterns. Zeglinsky et al. (2012) investigated Sr-substituted HA by ab initio methods and Rietveld analyses and reported changes in the HA unit cell volume and shape due to the Sr addition. To further clarify the role played by the addition of Sr on the physico-chemical properties of these materials we prepared Sr-substituted HA compositions by a solid state method, using different reagents, thermal treatments and a multi-technique approach. Our results indicated that the introduction of Sr at the levels considered here does influence the structure of HA. There is also evidence of a decrease in the crystallinity degree of the materials upon Sr addition. The introduction of increasing amounts of Sr into the HA composition causes a decrease in the specific surface area and an enrichment of Sr-apatite phase at the surface of the samples. Bioactivity tests show that the presence of Sr causes changes in particle size and/or morphology during soaking in MEM solution; on the contrary the morphology of pure HA does not change after 14 days of reaction. The presence of Sr, as Sr-substituted HA and SrCl{sub 2,} in cultures of human MG-63 osteoblasts did not produce any cytotoxic effect. In fact, Sr-substituted HA increased the proliferation of osteoblast cells and enhanced cell differentiation: Sr in

  14. Sr-containing hydroxyapatite: morphologies of HA crystals and bioactivity on osteoblast cells

    International Nuclear Information System (INIS)

    Aina, Valentina; Bergandi, Loredana; Lusvardi, Gigliola; Malavasi, Gianluca; Imrie, Flora E.; Gibson, Iain R.; Cerrato, Giuseppina; Ghigo, Dario

    2013-01-01

    A series of Sr-substituted hydroxyapatites (HA), of general formula Ca (10−x) Sr x (PO 4 ) 6 (OH) 2 , where x = 2 and 4, were synthesized by solid state methods and characterized extensively. The reactivity of these materials in cell culture medium was evaluated, and the behavior towards MG-63 osteoblast cells (in terms of cytotoxicity and proliferation assays) was studied. Future in vivo studies will give further insights into the behavior of the materials. A paper by Lagergren et al. (1975), concerning Sr-substituted HA prepared by a solid state method, reports that the presence of Sr in the apatite composition strongly influences the apatite diffraction patterns. Zeglinsky et al. (2012) investigated Sr-substituted HA by ab initio methods and Rietveld analyses and reported changes in the HA unit cell volume and shape due to the Sr addition. To further clarify the role played by the addition of Sr on the physico-chemical properties of these materials we prepared Sr-substituted HA compositions by a solid state method, using different reagents, thermal treatments and a multi-technique approach. Our results indicated that the introduction of Sr at the levels considered here does influence the structure of HA. There is also evidence of a decrease in the crystallinity degree of the materials upon Sr addition. The introduction of increasing amounts of Sr into the HA composition causes a decrease in the specific surface area and an enrichment of Sr-apatite phase at the surface of the samples. Bioactivity tests show that the presence of Sr causes changes in particle size and/or morphology during soaking in MEM solution; on the contrary the morphology of pure HA does not change after 14 days of reaction. The presence of Sr, as Sr-substituted HA and SrCl 2, in cultures of human MG-63 osteoblasts did not produce any cytotoxic effect. In fact, Sr-substituted HA increased the proliferation of osteoblast cells and enhanced cell differentiation: Sr in HA has a positive effect

  15. Rapid Simultaneous Determination of 89Sr and 90Sr in Milk: A Procedure Using Cerenkov and Scintillation Counting

    International Nuclear Information System (INIS)

    2013-01-01

    Since 2004, the IAEA programme related to the terrestrial environment has included activities aimed at developing and testing a set of procedures for the determination of radionuclides in environmental samples. Both 89Sr and 90Sr are fission products that can be, and have been, released to the environment during nuclear explosions and nuclear reactor accidents. Since strontium uptake from milk is an important pathway for incorporation of radioactive strontium into the human body, the rapid and accurate analysis of radioactive strontium isotopes in milk is of crucial importance in emergency situations in order to protect the public from radiation hazards. This report describes a new approach for the rapid determination of 89 Sr and 90Sr in milk using Cerenkov and scintillation counting methods that was tested and validated by the analysis of four spiked milk samples in terms of repeatability, reproducibility and trueness (relative bias) in accordance with ISO guidelines. The report also describes the calculation of the uncertainty budget. This research was proposed in 2007 at the Asia-Pacific regional meeting of the IAEA Analytical Laboratories for the Measurement of Environmental Radioactivity (ALMERA) network. Several ALMERA network laboratories participated in the validation procedure by performing reproducibility tests. The resulting recommended procedure is designed to be of general use to a wide range of laboratories, including those in the ALMERA network. It is expected that this rapid method for determining 89 Sr and 90 Sr in milk will be useful in emergency conditions and for routine environmental monitoring of elevated levels of radioactivity

  16. Effect of SrO content on Zeolite Structure

    Science.gov (United States)

    Widiarti, N.; Sari, U. S.; Mahatmanti, F. W.; Harjito; Kurniawan, C.; Prasetyoko, D.; Suprapto

    2018-04-01

    The aims of current studies is to investigate the effect of strontium oxide content (SrO) on synthesized zeolite. Zeolite was synthesized from Tetraethyl orthosilicate (TEOS) as precursors of SiO2 and aluminum isopropoxide (AIP) precursors. The mixture was aged for 3 days and hydrothermally treated for 6 days. The SrO content was added by impregnation method. The products were then characterized using X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR), and Surface Area Analyzer (SAA). The diffractogram confirmed the formation of Faujasite-like zeolite. However, after the addition of SrO, the crystallinity of zeolite was deformed. The diffractograms shows the amorphous phase of zeolite were decrease as the SrO content is increase. The structural changes was also observed from FTIR spectra which shows the shifting and peak formation. The surface area analysis showed that the increasing loading of SrO/Zeolites reduced the catalyst surface area.

  17. Sr-90 determination in aqueous and soils samples

    International Nuclear Information System (INIS)

    Gonzalez Sintas, Maria F.; Cerchietti, Maria L.; Arguelles, Maria G.

    2009-01-01

    The main objective of this paper is to evaluate the method for Sr-90 determination in aqueous sample and soils. Area and Personal Dosimetry laboratory (DPA) determines the presence of Sr-90 by Liquid Scintillation (LSC) by applying method of the double window and corresponding adjustments. Calibration is performed by standard solutions of 90 Sr/ 90 Y, where spectral 90 Sr and 90 Y zones are optimized. The initial treatment of the liquid samples includes the concentration for evaporation, while the solid ones dissolve for microwave and acidic digestion. The separation of the analyte involves a selective chromatographic extraction. An average efficiency for 90 Sr of 77 ± 1 % was obtained; the factor a/b was 0,85 ± 0,01 and recovery of 82 ± 8 %. The resultant MAD was 0,10 Bq/L in aqueous samples and 0,10 Bq/g in solid samples. (author)

  18. Resistance switching in epitaxial SrCoOx thin films

    Science.gov (United States)

    Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk; Kim, Yeon Soo; Park, Bae Ho; Jeong, Huiseong; Park, Ji-Yong; Cho, Myung Rae; Park, Yun Daniel; Choi, Woo Seok; Kim, Dong-Wook; Jin, Hyunwoo; Lee, Suyoun; Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong

    2014-08-01

    We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO3 (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO2.5) and conducting perovskite (SrCoO3-δ) depending on the oxygen content. The current-voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoOx thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO2.5.

  19. Resistance switching in epitaxial SrCoOx thin films

    International Nuclear Information System (INIS)

    Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk; Kim, Yeon Soo; Park, Bae Ho; Jeong, Huiseong; Park, Ji-Yong; Cho, Myung Rae; Park, Yun Daniel; Choi, Woo Seok; Kim, Dong-Wook; Jin, Hyunwoo; Lee, Suyoun; Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong

    2014-01-01

    We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO 3 (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO 2.5 ) and conducting perovskite (SrCoO 3−δ ) depending on the oxygen content. The current–voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoO x thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO 2.5

  20. Trace determination of 90Sr and 89Sr in environmental samples by collinear resonance ionization spectroscopy

    International Nuclear Information System (INIS)

    Lantzsch, J.; Bushaw, B. A.; Bystrow, V. A.; Herrmann, G.; Kluge, H.-J.; Niess, S.; Otten, E. W.; Passler, G.; Schwalbach, R.; Schwarz, M.; Stenner, J.; Trautmann, N.; Wendt, K.; Yushkevich, Y. V.; Zimmer, K.

    1995-01-01

    Collinear resonance ionization spectroscopy has been developed as a sensitive technique for fast trace detection of 90 Sr and 89 Sr in the environment. A detection limit for 90 Sr of 10 7 atoms in the presence of 10 17 atoms in the presence of 10 17 atoms of stable Strontium has been achieved, while the applicability of the method has been demonstrated on real world samples. After collection and chemical separation, strontium is surface ionized, accelerated to 33keV and mass separated. The ions are neutralized and the emerging fast atoms interact with an argon ion laser beam (γ=364 nm) in a quasi-collinear geometry. Optical excitation starts from the long-lived 5s4d 3 D2 state of strontium, which is populated in the charge exchange process, and the fast atoms are selectively excited into the high-lying 5s23f 3 F3 Rydberg state. The Rydberg-atoms are subsequently field-ionized and detected by a channeltron detector after energy selection. The described method was successfully used to determine the 90 Sr-content in air samples collected near Munich during the Chernobyl reactor accident in April 1986

  1. Unconventional superconductivity in Sr{sub 2}RuO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ying [Department of Physics and Materials Research Institute, Pennsylvania State University, University Park, PA 16802 (United States); Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093 (China); Mao, Zhi-Qiang [Department of Physics and Engineering Physics, Tulane University, New Orleans, LA 70118 (United States)

    2015-07-15

    Highlights: • Constraints on and experimental support to unconventional superconductivity in Sr{sub 2}RuO{sub 4}. • Phase-sensitive determination of the pairing symmetry in Sr{sub 2}RuO{sub 4}. • Response of superconductivity to mechanical perturbations. • Superconductivity in non-bulk Sr{sub 2}RuO{sub 4}. • Unresolved issues and outlook in Sr{sub 2}RuO{sub 4} research. - Abstract: Sr{sub 2}RuO{sub 4}, featuring a layered perovskite crystalline and quasi-two-dimensional electronic structure, was first synthesized in 1959. Unconventional, p-wave pairing was predicted for Sr{sub 2}RuO{sub 4} by Rice and Sigrist and Baskaran shortly after superconductivity in this material was discovered in 1994. Experimental evidence for unconventional superconductivity in Sr{sub 2}RuO{sub 4} has been accumulating in the past two decades and reviewed previously. In this article, we will first discuss constraints on the pairing symmetry of superconductivity in Sr{sub 2}RuO{sub 4} and summarize experimental evidence supporting the unconventional pairing symmetry in this material. We will then present several aspects of the experimental determination of the unconventional superconductivity in Sr{sub 2}RuO{sub 4} in some detail. In particular, we will discuss the phase-sensitive measurements that have played an important role in the determination of the pairing symmetry in Sr{sub 2}RuO{sub 4}. The responses of superconductivity to the mechanical perturbations and their implications on the mechanism of superconductivity will be discussed. A brief survey of various non-bulk Sr{sub 2}RuO{sub 4} will also be included to illustrate the many unusual features resulted from the unconventional nature of superconductivity in this material system. Finally, we will discuss some outstanding unresolved issues on Sr{sub 2}RuO{sub 4} and provide an outlook of the future work on Sr{sub 2}RuO{sub 4}.

  2. Topotactic phase transformation of the brownmillerite SrCoO2.5 to the perovskite SrCoO3- δ.

    Science.gov (United States)

    Jeen, H; Choi, W S; Freeland, J W; Ohta, H; Jung, C U; Lee, H N

    2013-07-19

    Pulsed laser epitaxy of brownmillerite SrCoO2.5 thin films and their phase transformation to the perovskite SrCoO3-δ are investigated. While the direct growth of the fully oxidized perovskite films is found to be an arduous task, filling some of oxygen vacancies into SrCoO2.5 by topotactic oxidation accompanies systematic evolution of electronic, magnetic, and thermoelectric properties, useful for many information and energy technologies. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. [Exogenous Sr2+ sedimentation on otolith of chum salmon embryos].

    Science.gov (United States)

    Wang, Chen; Liu, Wei; Zhan, Pei-rong; Wang, Ji-long; Li, Pei-lun

    2015-10-01

    To explore the exogenous Sr2+ sedimentation on otolith of chum salmon embryos, chum salmon embryos were exposed to culture water contained Sr2+ at Sr2+ concentration of 50, 100, 200 or 400 mg . L-1 for 48 h to imitate Sr2+ sedimentation. After a culturing period of 12 d and 100 d, the otoliths of the chum salmon were taken to detect exogenous Sr2+ sedimentation with electro-probe microanalyzer (EPMA). The results showed that obvious deep red strontium signatures were produced in the otolith of chum salmon at different concentrations of Sr2+. The mean and extreme values of peak strontium area were not stable for the same Sr2+ dose, but the lowest of all the peak values was 35.1 times as much as that of control. Overall, the strontium value increased with the increase of Sr2+concentration. The strontium peak had no signs of abating after a culture period of 100 d. The results also showed that strontium was gradually deposited in the otolith, and had obvious hysteresis to immersion. Strontium sedimentation could also return to a normal level after the peak. These characteristics accorded exactly with the requirement of discharge tag technology, which indicated that exogenous Sr2+ was suitable in the marking of salmon otolith.

  4. Energy transfer in Pr3+ and Mn2+ co-doped SrB6O10 and SrB4O7

    International Nuclear Information System (INIS)

    Chen Yonghu; Yan Wuzhao; Shi Chaoshu

    2007-01-01

    The luminescent properties of Pr 3+ and Mn 2+ -doped SrB 6 O 10 and SrB 4 O 7 powder samples were investigated from the point of view of energy transfer between Pr 3+ and Mn 2+ . The emission from the 1 S 0 level of Pr 3+ was found in the SrB 6 O 10 :Pr 3+ sample as well as in the SrB 4 O 7 :Pr 3+ sample, indicating the 1 S 0 level is below the lowest 4f5d energy level in these hosts. The spectral overlaps between the emission spectra of Pr 3+ -doped samples and the excitation spectra of Mn 2+ -doped sample were found in both kinds of strontium borates. These spectral overlaps are in favor of the energy transfer from Pr 3+ to Mn 2+ . However, in the emission spectra of the SrB 6 O 10 :Pr 3+ , Mn 2+ , no indication of energy transfer was observed, though the emission spectra of SrB 4 O 7 :Pr 3+ , Mn 2+ did show evidence of energy transfer from Pr 3+ to Mn 2+ . The possible reasons were discussed

  5. Rb-Sr isochrone dating of granitoids from Tribec Mts

    International Nuclear Information System (INIS)

    Bagdasaryan, G.P.; Gukasyan, R.Kh.; Cambel, B.; Broska, I.

    1990-01-01

    The results of Rb-Sr isochrone dating of granitoids from the Tribec-Zobor crystalline complex region are presented. Whole-rock Rb-Sr isochrone indicates an age of 352±5 m.y., the initial ratio being ( 87 Sr/ 86 Sr) 0 =0.70582±0.00008, which approaches the hitherto published initial ratios from the Tatric-Veporide part of the crystalline complex. This indicates a common source of granitoid rocks over the entire region studied. (author). 2 figs., 1 tab., 15 refs

  6. Determination of Cs-137, Sr-89 and Sr-90 and gamma spectroscopy of water samples from the Danube River

    International Nuclear Information System (INIS)

    Tschurlovits, M.

    1980-01-01

    Radioactivity concentration of Cs-137, Sr-90, Sr-89, Co-60 and K-40 from the Danube water in the period of 1977-1979. A few systematic changes in the radioactivity concentrations were observed and presented. (author)

  7. Development of {sup 90}Sr-{sup 90}Y generators; Desenvolvimento de geradores de {sup 90}Sr-{sup 90}Y

    Energy Technology Data Exchange (ETDEWEB)

    Barrio, Graciela, E-mail: gracielabarrio@gmail.co [Pontificia Univ. Catolica de Sao Paulo (PUC-SP), SP (Brazil). Dept. de Fisica; Osso Junior, Joao Alberto, E-mail: jaossoj@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2007-07-01

    Yttrium-90 is a radioisotope of great interest in the field of Nuclear Medicine. It is considered one of the most important and most used radionuclides for radioimmunotherapeutical applications, especially promising for the treatment of certain types of cancer. Another important application of {sup 90}Y is radio synovectomy. This radionuclide has a half-life of 64 hours, emits long range beta particles (maximum energy of 2.3 MeV) and decays, without intermediate nuclides, to a stable daughter. {sup 90}Y may be obtained carrier-free, generated by the decay of its parent {sup 90}Sr (half-life=28 years). {sup 90}Sr is a product from uranium fission, and due to its long half-life, can be indefinitely used, which is certainly advantageous. It is present in great amounts, and needs to be processed and purified in order to be used as raw material for the generators. Generators of {sup 90}Sr-{sup 90}Y may thus be used during various months, due to {sup 90}Sr long half-life. Several methods for the separation of {sup 90}Y from {sup 90}Sr by solvent extraction and ion exchange have been reported in literature. Thanks to its simplicity, ion exchange techniques have been more commonly used for this generator system. The main objective of this work was to develop a methodology for the preparation of {sup 90}Sr-{sup 90}Y generators, using cationic exchange resins. In such method, {sup 90}Sr is strongly adsorbed in the resin and {sup 90}Y is eluted by a 0.003 M EDTA solution. According to the quality control carried out, results showed that elution yields are greater than 65%, thus confirming the efficiency of the separation method used.

  8. Nature and Significance of the High-Sr Aleutian Lavas

    Science.gov (United States)

    Yogodzinski, G. M.; Arndt, S.; Turka, J. R.; Kelemen, P. B.; Vervoort, J. D.; Portnyagin, M.; Hoernle, K.

    2011-12-01

    Results of the Western Aleutian Volcano Expedition and German-Russian KALMAR cruises include the discovery of seafloor volcanism at the Ingenstrem Depression and at unnamed seamounts 300 km west of Buldir, the westernmost emergent volcano in the Aleutian arc. These discoveries indicate that the surface expression of active Aleutian volcanism goes below sea level just west of Buldir, but is otherwise continuous along the full length of the arc. Many lavas dredged from western Aleutian seamounts are basalts, geochemically similar to basalts from elsewhere in Aleutians and other arcs (La/Yb 4-8, Sr/Y700 ppm Sr), which are mostly plagioclase-hornblende andesites and dacites with low Y and middle-heavy rare-earth elements, fractionated trace element patterns (Sr/Y=50-200, La/Yb=9-25) and MORB-like isotopes (87Sr/86Sr 0.65) with 1250-1700 ppm Sr, 4-7 ppm Y, low abundances of all rare-earth elements (LaMexico. [1] Zimmer et al., 2010, J. Petrology, v. 51, p. 2411

  9. Analysis of uncertainties and detection limits for the double measurement method of {sup 90}Sr and {sup 89}Sr

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, M., E-mail: m.herranz@ehu.es [Department of Nuclear Engineering and Fluid Mechanics, University of the Basque Country (UPV/EHU), Alameda de Urquijo s/n 48013 Bilbao (Spain); Idoeta, R.; Legarda, F. [Department of Nuclear Engineering and Fluid Mechanics, University of the Basque Country (UPV/EHU), Alameda de Urquijo s/n 48013 Bilbao (Spain)

    2011-08-15

    The determination process of the {sup 90}Sr and {sup 89}Sr contents in a sample, although it involves their radiochemical isolation, results always in a complex measurement process due to the interferences among their respective beta emissions and also among those of the daughter of {sup 90}Sr, {sup 90}Y, a beta emitter as well. In this paper, the process consisting in a double measurement method after the Sr radiochemical isolation is analyzed, developing the formulae to obtain activity concentrations, uncertainties and detection limits. A study of the trend of uncertainties and detection limits as function of the time in which the first measurement since the isolation is done, the delay between the two measurements and the activity concentration of each strontium isotope in the sample is carried out as well. Results show that with a very precise determination of the times involved in the whole process (isolation, measurement and duration of measurements) this method permits a reliable assessment of both strontium radioisotopes. The quicker the first measurement since the isolation is done and the longer the delay between measurements is chosen, the lower are the detection limits and the uncertainties of the activities obtained. - Highlights: > The double measurement method for {sup 90}Sr and {sup 89}Sr determination is analysed. > Uncertainties and detection limits are determined and their dependences studied. > Proposals for the optimization of the method are given.

  10. Physiological studies in heterozygous calcium sensing receptor (CaSR gene-ablated mice confirm that the CaSR regulates calcitonin release in vivo

    Directory of Open Access Journals (Sweden)

    Kovacs Christopher S

    2004-04-01

    Full Text Available Abstract Background The calcium sensing receptor (CaSR regulates serum calcium by suppressing secretion of parathyroid hormone; it also regulates renal tubular calcium excretion. Inactivating mutations of CaSR raise serum calcium and reduce urine calcium excretion. Thyroid C-cells (which make calcitonin express CaSR and may, therefore, be regulated by it. Since calcium stimulates release of calcitonin, the higher blood calcium caused by inactivation of CaSR should increase serum calcitonin, unless CaSR mutations alter the responsiveness of calcitonin to calcium. To demonstrate regulatory effects of CaSR on calcitonin release, we studied calcitonin responsiveness to calcium in normal and CaSR heterozygous-ablated (Casr+/- mice. Casr+/- mice have hypercalcemia and hypocalciuria, and live normal life spans. Each mouse received either 500 μl of normal saline or one of two doses of elemental calcium (500 μmol/kg or 5 mmol/kg by intraperitoneal injection. Ionized calcium was measured at baseline and 10 minutes, and serum calcitonin was measured on the 10 minute sample. Results At baseline, Casr+/- mice had a higher blood calcium, and in response to the two doses of elemental calcium, had greater increments and peak levels of ionized calcium than their wild type littermates. Despite significantly higher ionized calcium levels, the calcitonin levels of Casr+/- mice were consistently lower than wild type at any ionized calcium level, indicating that the dose-response curve of calcitonin to increases in ionized calcium had been significantly blunted or shifted to the right in Casr+/- mice. Conclusions These results confirm that the CaSR is a physiological regulator of calcitonin; therefore, in response to increases in ionized calcium, the CaSR inhibits parathyroid hormone secretion and stimulates calcitonin secretion.

  11. Photoluminescence in Pb{sup 2+} activated SrB{sub 4}O{sub 7} and SrB{sub 2}O{sub 4} phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Gawande, A.B., E-mail: gawandeab@gmail.com [Department of Physics, SGB Amravati University, Amravati-444602, Maharashtra (India); Ingle, J.T. [J. D. Institute of Engineering and Technology, Yavatmal, Maharashtra (India); Sonekar, R.P., E-mail: sonekar_rp@yahoo.com [Department of Physics, G.S. College, Khamgaon District, Buldhana, Maharashtra (India); Omanwar, S.K. [Department of Physics, SGB Amravati University, Amravati-444602, Maharashtra (India)

    2014-05-01

    The powder samples of SrB{sub 4}O{sub 7}:Pb{sup 2+} and SrB{sub 2}O{sub 4}:Pb{sup 2+} were prepared by solution combustion synthesis method. The synthesis is based on the exothermic reaction between the fuel (Urea) and Oxidizer (Ammonium nitrate). The synthesized materials were characterized using TG–DTA, powder XRD, SEM and the photoluminescence properties were studied using a Hitachi F-7000 spectrophotometer at room temperature. Both the samples SrB{sub 4}O{sub 7}:Pb{sup 2+} and SrB{sub 2}O{sub 4}:Pb{sup 2+} show broad emission of Pb{sup 2+} respectively at 307 nm and 360 nm (corresponds to {sup 3}P{sub 1} to {sup 1}S{sub 0} transition). The optimum concentrations of Pb{sup 2+} in both the phosphors SrB{sub 4}O{sub 7}:Pb{sup 2+} and SrB{sub 2}O{sub 4}:Pb{sup 2+} were found to be 3 mol% (relative to Sr) and for this concentration the critical transfer distance R{sub 0} were calculated to be 10.21 Å and 12.22 Å respectively. The Stokes shifts were calculated to be respectively 4464 cm{sup −1} and 8454 cm{sup −1}. The emission bands of both the phosphors are in the UV region and the phosphors can be potential candidates for application in UV lamps. - Highlights: • SrB{sub 4}O{sub 7}:Pb{sup 2+} and SrB{sub 2}O{sub 4}:Pb{sup 2+} have been synthesized by Novel solution combustion synthesis technique. • The synthesized materials were characterized using TG–DTA, powder XRD and SEM. • Photoluminescence spectra of synthesized materials showed the characteristic transition in Pb{sup 2+}. • Stokes shift, optimum concentration and critical transfer distance R{sub 0} were determined.

  12. The combined use of 87Sr/86Sr and carbon and water isotopes to study the hydrochemical interaction between groundwater and lakewater in mantled karst

    Science.gov (United States)

    Katz, Brian G.; Bullen, Thomas D.

    1996-12-01

    The hydrochemical interaction between groundwater and lakewater influences the composition of water that percolates downward from the surficial aquifer system through the underlying intermediate confining unit and recharges the Upper Floridan aquifer along highlands in Florida. The 87Sr/86Sr ratio along with the stable isotopes, D, 18O, and 13C were used as tracers to study the interaction between groundwater, lakewater, and aquifer minerals near Lake Barco, a seepage lake in the mantled karst terrane of northern Florida. Upgradient from the lake, the 87Sr/86Sr ratio of groundwater decreases with depth (mean values of 0.71004, 0.70890, and 0.70852 for water from the surficial aquifer system, intermediate confining unit, and Upper Floridan aquifer, respectively), resulting from the interaction of dilute oxygenated recharge water with aquifer minerals that are less radiogenic with depth. The concentrations of Sr2+ generally increase with depth, and higher concentrations of Sr2+ in water from the Upper Floridan aquifer (20-35 μg/L), relative to water from the surficial aquifer system and the intermediate confining unit, result from the dissolution of Sr-bearing calcite and dolomite in the Eocene limestone. Dissolution of calcite [δ13C= -1.6permil(‰)] is also indicated by an enriched δ13CDIC(-8.8 to -11.4 ‰) in water from the Upper Floridan aquifer, relative to the overlying hydrogeologic units (δ13CDICaquifer material become less radiogenic and the Sr2+ concentrations generally increase with depth. However, Sr2+ concentrations are substantially less than in upgradient groundwaters at similar depths. The lower Sr2+ concentrations result from the influence of anoxic lakewater leakage on the mobility of Sr2+ from clays. Based on results from mass-balance modeling, it is probable that cation exchange plays the dominant role in controlling the 87Sr/86Sr ratio of groundwater, both upgradient and downgradient from Lake Barco. Even though groundwater from the three

  13. Some analytical aspects about determination of Sr89 and Sr90 in environmental samples

    International Nuclear Information System (INIS)

    Gasco, C.; Alvarez Garcia, A.

    1988-01-01

    Some problems about determination of Sr 89 and Sr 90 in environmental samples have been studied. The main difficulties are due to the wide range in the concentration of their components and the contents of chemical and radiochemical interferent elements. The behaviour of strontium on ion exchange resin has been described by some experiments in various media: aqueous media, calcium concentration and matrix variable. The differences of alkaline-earth nitrate and carbonate solubilities have been analyzed in nitric acid. The chemical recovery in environmental samples has been determined. (Author)

  14. Spark plasma sintering of bulk SrAl2O4-Sr3Al2O6 eutectic glass with wide-band optical window

    Science.gov (United States)

    Liu, Jiaxi; Lu, Nan; He, Gang; Li, Xiaoyu; Li, Jianqiang; Li, Jiangtao

    2018-06-01

    SrAl2O4-Sr3Al2O6 eutectic glass was prepared by using an aerodynamic levitator equipped with a CO2 laser device. A bulk transparent amorphous sample was obtained by the spark plasma sintering (SPS) of the prepared eutectic glass. XRD, a UV–vis-NIR spectrophotometer and FT-IR were employed to characterize the phase evolution and optical properties. The results show that the bulk SrAl2O4-Sr3Al2O6 samples fabricated by the containerless process and SPS between 852 °C–857 °C were fully amorphous. The amorphous sample has a wide transparent window between 270 nm and 6.2 μm. The average refractive index in the visible light region is 1.680 and the Abbe number is 27.4. The prepared bulk SrAl2O4-Sr3Al2O6 eutectic glass with the wide-band optical window may be a promising candidate for optical applications.

  15. High-pressure modifications of CaZn2, SrZn2, SrAl2, and BaAl2: Implications for Laves phase structural trends

    International Nuclear Information System (INIS)

    Kal, Subhadeep; Stoyanov, Emil; Belieres, Jean-Philippe; Groy, Thomas L.; Norrestam, Rolf; Haeussermann, Ulrich

    2008-01-01

    High-pressure forms of intermetallic compounds with the composition CaZn 2 , SrZn 2 , SrAl 2 , and BaAl 2 were synthesized from CeCu 2 -type precursors (CaZn 2 , SrZn 2 , SrAl 2 ) and Ba 21 Al 40 by multi-anvil techniques and investigated by X-ray powder diffraction (SrAl 2 and BaAl 2 ), X-ray single-crystal diffraction (CaZn 2 ), and electron microscopy (SrZn 2 ). Their structures correspond to that of Laves phases. Whereas the dialuminides crystallize in the cubic MgCu 2 (C15) structure, the dizincides adopt the hexagonal MgZn 2 (C14) structure. This trend is in agreement with the structural relationship displayed by sp bonded Laves phase systems at ambient conditions. - Graphical abstract: CeCu 2 -type polar intermetallics can be transformed to Laves phases upon simultaneous application of pressure and temperature. The observed structures are controlled by the valence electron concentration

  16. Sistemas de Información Gerencial en los procesos de negocio de las PyMEs de Jujuy

    OpenAIRE

    Castillo, César A.; Herrera Cognetta, Analía; Rico, Lía G.; Salva, Sergio; Sarmiento, Julián; Tejerina, Mario; Villarrubia, Laura R.

    2013-01-01

    El equipo de investigación ha planteado como fundamento para estudio e investigación, la siguiente hipótesis: “la implementación de Sistemas de Información Gerencial en las Pequeñas y Medianas Empresas de la provincia de Jujuy, aportará grandes ventajas para su eficiente administración y crecimiento”. A fin de refutar o confirmar ésta, se ha iniciado el correspondiente relevamiento en las PyMEs de la provincia, en lo concerniente a su situación actual, analizando además, sus necesidades de in...

  17. Experimental investigation and thermodynamic calculation of the Mg-Sr-Zr system

    International Nuclear Information System (INIS)

    Zhou, Hua; Chen, Chong; Du, Yong; Central South Univ., Hunan; Gong, Haoran

    2016-01-01

    Both experimental investigation and thermodynamic calculation were performed for the Mg-Sr-Zr system. Four decisive alloys were firstly selected and prepared using a powder metallurgy method to measure the isothermal section at 400 C via a combination of X-ray diffraction and electron probe microanalysis. No ternary compound has been observed for this ternary system. Four three-phase regions, (Mg) + (αZr) + Mg 17 Sr 2 , Mg 17 Sr 2 + (αZr) + Mg 38 Sr 9 , Mg 38 Sr 9 + (αZr) + Mg 23 Sr 6 , and Mg 23 Sr 6 + (αZr) + Mg 2 Sr, have been identified at 400 C. No appreciable ternary solubility has been detected in the binary Mg-Sr compounds. Phase transition temperatures of the Mg-Sr-Zr alloys were measured by means of differential scanning calorimetry. The thermodynamic calculations match well with the experimental data in the present work, indicating that no ternary thermodynamic parameters are needed for the thermodynamic description of this ternary system. In order to verify the reliability of the current thermodynamic calculations of the Mg-Sr-Zr system, eight as-cast alloys in the Mg-rich corner were also prepared. The calculated liquidus projection is consistent with the observed primary phase regions. The present thermodynamic calculations are reliable and can be used in the development of Mg alloys.

  18. Strontium adsorption and penetration in kaolinite at low Sr

    NARCIS (Netherlands)

    Ning, Zigong; Ishiguro, Munehide; Koopal, Luuk K.; Sato, Tsutomu; Kashiwagi, Junichi

    2017-01-01

    Behavior of radioactive strontium (Sr2+) in contaminated soils is an important issue in relation to nuclear power plant accidents. The Sr2+ adsorption on kaolinite and its migration in a kaolinite soil were investigated because toxic effects of radioactive Sr2+ have been found to be very severe for

  19. 87Sr/86Sr in gypsic soils of hyperarid settings as an altitude proxy: results for northern Chile (19-22°S) and paleoaltimetry applications

    Science.gov (United States)

    Cosentino, N. J.; Jordan, T. E.; Derry, L. A.

    2012-12-01

    Quantification of uplift of a continental surface relative to sea level is still challenging. We have developed a new altimeter based on the 87Sr/86Sr ratio of modern accumulations of salts (incipient soils) in hyperarid settings like those present in northern Chile's Atacama Desert, which lies in the forearc of the Nazca-South America plate system. The proposed altimeter is based on the first order topographic control on the extent of coastal fog. Advective events bring offshore-generated stratocumulus clouds to the continent, generating fog between 400 and 1100 m.a.s.l.. In the hyperarid desert, thin layers of calcium sulfate, among other salts, accumulate on the surface. The main sources of the calcium sulfates are i) Pacific-sourced fog that transports aerosols and dissolved salts inland, which are precipitated upon evaporation, ii) wind that transports salts derived from the weathering of Andean magmatic arc rocks, which may be recycled through salars, and to a lesser extent, iii) salts derived from volcanic emissions. While the latter two have an average 87Sr/86Sr isotopic ratio of 0.70749, the fog source has a value corresponding to seawater (0.70917). Due to the high atomic weight of Sr and to the low relative mass difference of isotopes 87Sr and 86Sr, environmental isotopic fractionation is minimal. This makes 87Sr/86Sr an excellent proxy for the primary source of the calcium sulfates and the calcium sulfates' Sr. Samples from four E-W transects of the forearc between 19.75° to 23.75° S demonstrate variations in 87Sr/86Sr for altitudes between 200 and 2700 m.a.s.l.. There is a correlation between the modern salts' 87Sr/86Sr and its altitude of formation for altitudes between ~400 and ~800 m.a.s.l., above which the 87Sr/86Sr falls abruptly until reaching values similar to or lower than the Andean average. The fact that this correlation is observed for the whole dataset (including all four transects) suggests that the relationship is regional rather than

  20. RADIOISOTOPE INVENTORY FOR TSPA-SR

    International Nuclear Information System (INIS)

    Leigh, C.; Rechard, R.

    2001-01-01

    The total system performance assessment for site recommendation (TSPA-SR), on Yucca Mountain, as a site (if suitable) for disposal of radioactive waste, consists of several models. The Waste Form Degradation Model (i.e, source term) of the TSPA-SR, in turn, consists of several components. The Inventory Component, discussed here, defines the inventory of 26 radioisotopes for three representative waste categories: (1) commercial spent nuclear fuel (CSNF), (2) US Department of Energy (DOE) spent nuclear fuel (DSNF), and (3) high-level waste (HLW). These three categories are contained and disposed of in two types of waste packages (WPs)--CSNF WPs and co-disposal WPs, with the latter containing both DSNF and HLW. Three topics are summarized in this paper: first, the transport of radioisotopes evaluated in the past; second, the development of the inventory for the two WP types; and third, the selection of the most important radioisotopes to track in TSPA-SR

  1. The spatial variation of initial 87Sr/86Sr ratios in the Toki granite, Central Japan. Implications for the intrusion and cooling processes of a granitic pluton

    International Nuclear Information System (INIS)

    Yuguchi, Takashi; Tsuruta, Tadahiko; Hama, Katsuhiro; Nishiyama, Tadao

    2013-01-01

    The spatial variation in initial 87 Sr/ 86 Sr ratios (SrI) in the Toki granite, Central Japan, shows heterogeneity ranging from 0.708942 to 0.710069, which provides information on the intrusion and cooling processes of plutons. The Toki granite has three mineralogy-based rock facies: muscovite-biotite granite (MBG), hornblende-biotite granite (HBG) and biotite granite (BG). Large SrI values were found to be distributed at the western margin (west MBG) and the lithologically central region (central BG), while small SrI values were found at the northeast margin (northeast MBG). Regions with high and low Sr concentrations were also found in the Toki granite. In the Sr-rich samples, SrI (0.708942-0.709789) increases with 100/Sr (0.7-1.5). This geochemical trend extends towards the country sedimentary rocks of the Mino Terrane, which can be interpreted to result from assimilation and fractional crystallization (AFC) between the original granitic magma and the Mino sedimentary rocks. The SrI values in the Sr-rich regions show a correlation with the Alumina Saturation Index (ASI). In particular, the west MBG, with large SrI values, is classified as a peraluminous granitoid with large ASI, suggesting that the western margin of the pluton was strongly affected by assimilation during the intrusion process. The Sr-poor samples are present both in the central BG, with large SrI values, and in the northeast MBG, with small SrI values. The Sr-poor samples have small ASI and large differentiation indices, indicating that the central BG and the northeast MBG were generated either by different AFC process with different amounts of contaminants or by the intrusion and fractionation of different source magma with different SrI values. Overall, the geochemical spatial variations found in the Toki granite can be explained by various degrees of assimilation and fractional crystallization in the magma chamber and/or multi-stage intrusions with different degrees of crystallization of

  2. Geochemical tracing of As pollution in the Orbiel Valley (southern France): 87Sr/86Sr as a tracer of the anthropogenic arsenic in surface and groundwater.

    Science.gov (United States)

    Khaska, Mahmoud; Le Gal La Salle, Corinnne; Lancelot, Joël; Verdoux, Patrick; Boutin, René

    2014-05-01

    The environmental impacts of arsenic mining activities and their effects on ecosystem and human health are observed in many stream waters and groundwater. The aim of this study is to identify the origin of As content in a mining environment using Sr isotopes. At the Salsigne gold mine, before the closure in 2004, high arsenic content has been observed in surface water and groundwater in the Orbiel valley. At the site, immobilization of As, in As rich leachate, is carried out by adding CaO. High contrast in 87Sr/86Sr between Arsenic rich minerals associated with Variscan metamorphic rocks (0.714888-0.718835), together with rich As waste water (0.713463-715477), and the CaO (0.707593) allows as to trace the origin of anthropogenic As. In 2012, Orbiel stream waters were sampled monthly upstream and downstream from the ancient ore processing site and once after an important rainy event (117mm). The upstream valley samples showed low and relatively constant As content with natural regional background of 3.6 and 5.6 μg/L. The rainy event induced only a slight increase in the As content up to 6.3 μg/L. High 87Sr/86Sr ratios suggested an influence of radiogenic Sr issued from the Variscan metamorphic basement. Downstream from the area, the As content was at least10 time as high. In the wet season, stream water As content clearly increased to 13.9-24 μg/L, reaching 120.5 μg/L during the rainy event. Associated 87Sr/86Sr ratio showed to be less radiogenic (0.712276-0.714002). The anti correlation observed between As and 87Sr/86Sr suggest that As issued from a natural origin is characterised by a high 87Sr/86Sr compared to As derived from the CaO treatement used on site and characterized by a low 87Sr/86Sr ratio. During the dry season, increase in As content was observed reaching 110 μg/L. These highlights the contribution of alluvial groundwater to base flow, probably associated with As reach leachate from the site. Contribution from the alluvial aquifer is confirmed by

  3. Observation of Isotope Ratios (δ2H, δ18O, 87Sr/86Sr) of Tap Water in Urban Environments

    Science.gov (United States)

    Mancuso, C. J.; Tipple, B. J.; Ehleringer, J. R.

    2014-12-01

    Urban environments are centers for rapidly growing populations. In order to meet the culinary water needs of these areas, municipal water departments use water from multiple locations and/or sources, often piped differentially to different locations within a municipality. This practice creates isotopically distinct locations within an urban area and therefore provides insight to urban water management practices. In our study we selected urban locations in the Salt Lake Valley, UT (SLV) and San Francisco Bay Area, CA (SFB) where we hypothesized geographically distinct water isotopic ratio differences existed. Within the SLV, municipal waters come from the same mountainous region, but are derived from different geologically distinct watersheds. In contrast, SFB waters are derived from regionally distinct water sources. We hypothesized that the isotope ratios of tap waters would differ based upon known municipal sources. To test this, tap water samples were collected throughout the urban regions in SLV and SFB and analyzed for δ2H, δ18O and 87Sr/86Sr isotope ratios. Seasonal collections were also made to assess if isotope ratios differed throughout the year. Within SLV and SFB, different regions were characterized by distinct paired δ18O and 87Sr/86Sr values. These different realms also agreed with known differences in municipal water supplies within the general geographic region. Waters from different cities within Marin County showed isotopic differences, consistent with water derived from different local reservoirs. Seasonal variation was observed in paired δ18O and 87Sr/86Sr values of tap water for some locations within SLV and SFB, indicating management decisions to shift from one water source to another depending on demand and available resources. Our study revealed that the δ18O and 87Sr/86Sr values of tap waters in an urban region can exhibit significant differences despite close spatial proximity if districts differ in their use of local versus

  4. Report on nuclear energy in SR Slovenia

    International Nuclear Information System (INIS)

    1987-01-01

    Currently Yugoslavia has one 632 MWe nuclear power plant (NPP) of PWR design, located at Krsko in the Socialist Republic (SR) of Slovenia. Krsko NPP, which is a two-loop plant, started power operation in 1981. In general, reactor safety activities in the SR of Slovenia are mostly related to upgrading the safety of our Krsko NPP and to developing capabilities for use in future units. This report presents the nuclear safety related legislation and organization of the corresponding regulatory body, and the activities related to nuclear safety of the participating organizations in the SR of Slovenia in 1987.

  5. Transesterification of soybean oil catalyzed by Sr-doped cinder

    International Nuclear Information System (INIS)

    Nasreen, Sadia; Liu, Hui; Khan, Romana; Zhu, Xiao-chan; Skala, Dejan

    2015-01-01

    Highlights: • Sr-doped cinder catalyst was prepared and used for biodiesel synthesis. • A 99% of triglycerides conversion was achieved under optimal reaction conditions. • SrAl 2 Si 2 O 8 and Sr 5 Al 8 O 1 are determined as dominant compounds which are responsible for high catalytic activity. • Catalyst exhibits high activity and can be easily recovered and regenerated. • The Sr-doped cinder catalyst is used in 14 repeated runs. - Abstract: The Strontium doped cinder was prepared using the wet impregnation method and analyzed as catalyst for biodiesel synthesis. Different procedure for cinder impregnation were investigated (temperature and duration of catalyst calcinations, the concentration of SrCl 2 solution) and optimal condition was established: impregnation 20 g of cinder 2–5 mm particles with 0.2 M SrCl 2 solution followed by calcinations at 1000 °C for 4 h. The Sr-cinder activity was tested at 90–200 °C using 1–5% mass of catalyst with different molar ratio of methanol to soybean oil (from 9 to 36). The maximum triglycerides (TG) conversion of 99.0% with the Fatty Acid Methyl Esters (FAME) yield of 97.1% was obtained by using 4% catalyst at 180 °C, for 1 h, and methanol/oil molar ratio 24:1. Influence of free fatty acid (FFA) and water in soybean oil on catalyst activity was analyzed, too. The catalyst could be used for 14 times with TG conversion and FAME yield above 90% and 80% respectively. The Sr-doped cinder catalysts before and after transesterification were characterized using BET surface area, basic strength, X-ray diffraction (XRD), scanning electron microscopy (SEM) and ICP-AAS. Results showed that the formation of SrAl 2 Si 2 O 8 and Sr 5 Al 8 O 17 complexes should be the main reason for the catalytic activity of prepared catalyst. Slow decrease of catalyst activity during its repeated use is result of Sr–Al-glycerolate formation in reaction between Sr–Al complexes and glycerol

  6. Study on sorption capacity and characterization of Sr2+ on synthetic zeolite

    International Nuclear Information System (INIS)

    Wang Jinming; Yi Facheng

    2010-01-01

    Sr 2+ adsorption capacity of synthetic zeolite(ZF) are studied with the intermittence method, and ZF adsorbed the Sr 2+ is characterized and analyzed by XRD, as a reference for the evaluation of the disposal effectiveness of low and medium radwastes. The results show that Sr 2+ adsorption capacity of ZF is good, and the equilibrium time for ZF to adsorb Sr 2+ is in range of 5-14 days. Sr 2+ concentration has the greatest effect on ZF adsorption capacity,and the medium,temperature and pH value of the solution also have effect on ZF adsorption capacity. With the augment of Sr 2+ concentration,the Sr 2+ equilibrium adsorption quantity of ZF increases,but the equilibrium adsorption rate and equilibrium adsorption ratio decreases. Sr 2+ adsorption capacity of ZF improves with the augment of pH value. Sr 2+ adsorption capacity of ZF is complicate and varies with the different ion, concentration and other components in the medium solution. Sr 2+ adsorption capacity of ZF increases with the augment of temperature. As a whole, when Sr 2+ concentration in the solution is 0.005mol/L, the pH value of the solution, and the temperature of medium and solution have less effect on the Sr 2+ adsorption capacity of ZF, and the unit cell parameter of ZF adsorbed Sr 2+ decreases. (authors)

  7. 87Sr/86Sr sourcing of ponderosa pine used in Anasazi great house construction at Chaco Canyon, New Mexico

    Science.gov (United States)

    Reynolds, Amanda C.; Betancourt, Julio L.; Quade, Jay; Patchett, P. Jonathan; Dean, Jeffery S.; Stein, John

    2005-01-01

    Previous analysis of 87Sr/86Sr ratios shows that 10th through 12th century Chaco Canyon was provisioned with plant materials that came from more than 75 km away. This includes (1) corn (Zea mays) grown on the eastern flanks of the Chuska Mountains and floodplain of the San Juan River to the west and north, and (2) spruce (Picea sp.) and fir (Abies sp.) beams from the crest of the Chuska and San Mateo Mountains to the west and south. Here, we extend 87Sr/86Sr analysis to ponderosa pine (Pinus ponderosa) prevalent in the architectural timber at three of the Chacoan great houses (Pueblo Bonito, Chetro Ketl, Pueblo del Arroyo). Like the architectural spruce and fir, much of the ponderosa matches the 87Sr/86Sr ratios of living trees in the Chuska Mountains. Many of the architectural ponderosa, however, have similar ratios to living trees in the La Plata and San Juan Mountains to the north and Lobo Mesa/Hosta Butte to the south. There are no systematic patterns in spruce/fir or ponderosa provenance by great house or time, suggesting the use of stockpiles from a few preferred sources. The multiple and distant sources for food and timber, now based on hundreds of isotopic values from modern and archeological samples, confirm conventional wisdom about the geographic scope of the larger Chacoan system. The complexity of this procurement warns against simple generalizations based on just one species, a single class of botanical artifact, or a few isotopic values.

  8. BiCaSrCuO superconductors

    International Nuclear Information System (INIS)

    Polvi, V.M.; Niemi, K.J.

    1989-01-01

    BiCaSrCuO and BiPbCaSrCuO powders have been synthesized. Different research methods (SEM,EDS,XRF,SRD,DTA) have been used to characterize the bulk specimen and wires. Resistance and current density measured as a function of temperature are reported. The ceramic products contained several phases. Lead containing specimen gave the best results and the synthesis was easily reproducible

  9. The dynamics of accumulation and disappearance of 89Sr in tea

    International Nuclear Information System (INIS)

    Chen Chuanqun; Wang Shouxiang; Zhang Yongxi; Sun Zhiming

    1994-06-01

    The 89 Sr was put into a tea tree-soil system by different ways. The results showed that for 89 Sr put into the system through the above-ground 1 part of tea tree, its concentration in tea was much higher than that through soil. The concentration of 89 Sr in older tea was higher than that in shoot for the same treatment. The accumulation and disappearance of 89 Sr in tea varied with the treatments. For the treatment through the above-ground part, the concentrations of 89 Sr in older tea and shoot were monotonously decreasing with time. For the treatment through soil the concentration of 89 Sr in shoot increased initially to a maximum value, then decreased slowly; while the concentration of 89 Sr in older tea increased quickly in a definite period, then increased slowly to gain a saturated value. In addition, the values of concentration factor of 89 Sr in the older tea and shoot were determined, too

  10. Possible two-stage /sup 87/Sr evolution in the Stockdale Rhyolite

    Energy Technology Data Exchange (ETDEWEB)

    Compston, W.; McDougall, I. (Australian National Univ., Canberra. Research School of Earth Sciences); Wyborn, D. (Department of Minerals and Energy, Canberra (Australia). Bureau of Mineral Resources)

    1982-12-01

    The Rb-Sr total-rock data for the Stockdale Rhyolite, of significance for the Palaeozoic time scale, are more scattered about a single-stage isochron than expected from experimental error. Two-stage /sup 87/Sr evolution for several of the samples is explored to explain this, as an alternative to variation in the initial /sup 87/Sr//sup 86/Sr which is customarily used in single-stage dating models. The deletion of certain samples having very high Rb/Sr removes most of the excess scatter and leads to an estimate of 430 +- 7 m.y. for the age of extrusion. There is a younger alignment of Rb-Sr data within each sampling site at 412 +- 7 m.y. We suggest that the Stockdale Rhyolite is at least 430 m.y. old, that its original range in Rb/Sr was smaller than now observed, and that it experienced a net loss in Sr during later hydrothermal alteration at ca. 412 m.y.

  11. Rb-Sr mantle isochrons from oceanic regions

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, C; Hart, S R; Hofmann, A; James, D E [Carnegie Institution of Washington, D.C. (USA). Dept. of Terrestrial Magnetism

    1976-09-01

    Existing data for /sup 87/Sr//sup 86/Sr and Rb/Sr ratios of basalts from oceanic islands and mid-ocean spreading ridges show significant positive correlations on a Rb-Sr isochron diagram (when data are averaged by island group). Furthermore, tholeiites and alkali basalts occupy distinct non-overlapping fields on this plot. The tholeiite correlation is interpreted as a mantle isochron, and the agreement of this age (1.6+-0.2 b.y.) with that reported for Pb-Pb isochrons from oceanic basalts lends strong support to the use of such isochrons for tracing mantle evolution. Oceanic basalts are apparently sampling a mantle in which chemical heterogeneities have persisted for at least 1.5-2.0 b.y. The data support a kinematic model for the mantle in which a relatively uniform and non-radiogenic asthenosphere is penetrated by, and mixed with, blobs or plumes derived from an isolated (1.5-2 b.y.) and chemically heterogeneous mesosphere.

  12. The initial 87Sr/86Sr ratios of the Kirwan Volcanics of Dronning Maud Land: Comparison with the Kirkpatrick Basalt, Transantarctic Mountains

    International Nuclear Information System (INIS)

    Faure, G.; Bowman, J.R.; Elliot, D.H.

    1979-01-01

    A series of lava flows from Mountain B (6 0 13.9'W, 74 0 06.9'S) of the Kirwan Escarpment in Dronning Maud Land, Antarctica, is composed of tholeiite basalts of Jurassic age. Their chemical compositions are similar to those of Jurassic basalts elsewhere in Dronning Maud Land but differ from those of the Kirkpatrick Basalt of the Transantarctic Mountains. The basalts on Mountain B contain 50.39% SiO 2 , 9.7 ppm Rb, 174.4 ppm Sr, have a Rb/Sr ratio of 0.057, and a K/Rb ratio of 417. Their average initial 87 Sr/ 86 Sr ratio is 0.7044 +- 0.0010 (1sigma) which suggests that the magma from which they formed could have been derived from the upper mantle without extensive contamination with 87 Sr and other elements. These results confirm earlier suggestions that the Jurassic basalts of Dronning Maud Land differ significantly from the Kirkpatrick Basalt and the Ferrar Dolerite of the Transantarctic Mountains. These differences in chemical and Sr-isotopic composition may be related to tectonic activity and magma formation during the break-up of Gondwanaland. (Auth.)

  13. Electronic structure of Ca, Sr, and Ba under pressure.

    Science.gov (United States)

    Animalu, A. O. E.; Heine, V.; Vasvari, B.

    1967-01-01

    Electronic band structure calculations phase of Ca, Sr and Ba over wide range of atomic volumes under pressure electronic band structure calculations for fcc phase of Ca, Sr and Ba over wide range of atomic volumes under pressure electronic band structure calculations for fcc phase of Ca, Sr and Ba over wide range of atomic volumes under pressure

  14. The ternary post-transition metal carbodiimide SrZn(NCN)2

    International Nuclear Information System (INIS)

    Corkett, Alex J.; Konze, Philipp M.; Dronskowski, Richard

    2017-01-01

    SrZn(NCN) 2 , the first example of a ternary post-transition metal carbodiimide, was prepared by a solid-state metathesis reaction. The crystal structure was solved from PXRD data and found to adopt the orthorhombic (Cmcm) BaZnSO structure, a high symmetry modification of that expressed by the oxide analogue SrZnO 2 . Locally, SrZn(NCN) 2 features ZnN 4 tetrahedra and SrN 6 trigonal prisms similar to those in quarternary LiSr 2 M(NCN) 4 (M = Al 3+ and Ga 3+ ) phases, however, the overall topologies are distinct with single chains in the former and double chains in the latter. Electronic structure calculations indicate an indirect bandgap of about 2.95 eV in SrZn(NCN) 2 , slightly lower than the experimentally observed bandgap of 3.4 eV in SrZnO 2 and consistent with a greater degree of covalency. The structural similarities between SrZn(NCN) 2 and oxychalcogenide analogues highlight the pseudochalcogenide character of NCN 2- and suggest that the title compound may serve as a template for accessing novel ternary carbodiimides featuring tetrahedrally coordinated transition metals. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. 878787Sr/868686Sr anomalies in Late Cretaceous-Early Tertiary ...

    Indian Academy of Sciences (India)

    paper documents the occurrences of two positive. 87. Sr/. 86 ... Analysis of trace elemental and stable isotopic profiles, sedimentation history ... et al (1980) and report of similar anomalies from ...... through the financial assistance of Alexander von. Humboldt ... and extinction events in earth history; Science 240. 996–1002.

  16. Principles of μSR technics

    International Nuclear Information System (INIS)

    Chappert, J.

    1983-05-01

    Principles of muon spin rotation spectroscopy (μSR) are presented. Muons plus are only take into account because physical and chemical results obtained presently are obtained by them. Muon plus has two main characteristics when implanted in a sample: just, it can be considered as a interstitial site probe; then the muon plus can diffuse. Accordingly the quantities measured by μSR are a combination of static and dynamic properties of the muon plus and of the sample. A fluid characteristics is the possibility of munomium formation (μ + e - bound state) [fr

  17. Ab initio investigations of the strontium gallium nitride ternaries Sr 3GaN3 and Sr6GaN5: Promising materials for optoelectronic

    KAUST Repository

    Goumri-Said, Souraya

    2013-05-31

    Sr3GaN3 and Sr6GaN5 could be promising potential materials for applications in the microelectronics, optoelectronics and coating materials areas of research. We studied in detail their structural, elastic, electronic, optical as well as the vibrational properties, by means of density functional theory framework. Both of these ternaries are semiconductors, where Sr3GaN3 exhibits a small indirect gap whereas Sr6GaN5 has a large direct gap. Indeed, their optical properties are reported for radiation up to 40 eV. Charge densities contours, Hirshfeld and Mulliken populations, are reported to investigate the role of each element in the bonding. From the mechanical properties calculation, it is found that Sr6GaN5 is harder than Sr3GaN3, and the latter is more anisotropic than the former. The phonon dispersion relation, density of phonon states and the vibrational stability are reported from the density functional perturbation theory calculations. © 2013 IOP Publishing Ltd.

  18. The impact of Mg contents on Sr partitioning in benthic foraminifers

    NARCIS (Netherlands)

    Mewes, Antje; Langer, Gerald; Reichart, Gert Jan; de Nooijer, L.J.; Nehrke, Gernot; Bijma, Jelle

    2015-01-01

    Foraminiferal calcite Mg/Ca (Mg/CaCC) is used in paleoceanographic studies to reconstruct temperature. Furthermore, the Mg/CaCC is influenced by different seawater Mg/Ca (Mg/CaSW). Foraminiferal calcite Sr/Ca (Sr/CaCC) can potentially be used to reconstruct Sr/Ca ratios of seawater (Sr/CaSW). As

  19. Physicochemical compatibility of SrCeO3 with potential SOFC cathodes

    International Nuclear Information System (INIS)

    Tolchard, J.; Grande, T.

    2007-01-01

    The chemical and physical compatibility of SrCeO 3 is investigated with respect to LaMO 3 (M=Mn, Fe, Co) and La 2-x Sr x NiO 4 (x=0, 0.8), via the reaction of fine-grained powder compacts and solid-state diffusion couples. Compositions were chosen so as to give predictive insight into possible candidate materials for all-oxide electrochemical devices. Results show the primary reaction in these systems to be the dissolution of SrO from SrCeO 3 into the LaMO 3 /La 2-x Sr x NiO 4 , and corresponding formation of La-doped CeO 2 . Reaction kinetics are observed to be relatively fast, with element profiles suggesting the diffusion of Sr 2+ in ceria to be surprisingly rapid. It is demonstrated that perovskite starting materials represent poor candidates for use with SrCeO 3 , reacting completely to form Ruddlesden-Popper/K 2 NiF 4 type oxides. Reaction with La 2 NiO 4 is less pronounced, and formation of secondary phases suppressed for the composition La 1.2 Sr 0.8 NiO 4 . It is thus concluded that Ruddlesden-Popper type oxides represent good candidate materials for use with a SrCeO 3 -based electrolytes when doped with appropriate levels of Sr. - Graphical abstract: Assessment of the SrCeO 3 proton conductor shows this material to have poor chemical compatibility with LaMO 3 perovskite systems, but predicts coexistence with Ruddlesden-Popper type oxides

  20. Electromagnétisme fondements et applications : avec 300 exercices et problèmes résolus

    CERN Document Server

    Pérez, José-Philippe; Fleckinger, Robert

    1997-01-01

    Cet ouvrage fait partie de ceux qui l'on acquiert dès le début de ses études et que l'on conserve comme ouvrage de référence. Il rassemble en un seul volume les notions fondamentales de l'électromagnétisme et des diverses applications en physique. Il est construit en 30 chapîtres très structurés et illustrés de nombreux exercices et problèmes résolus. Le public Etudiants des DEUG Sciences (SM, MIAS, ST et SV) Etudiants des classes préparatoires (MP, PC, PSI) Etudiants des licences de physique Candidats aux concours d'enseignement.

  1. Solidification of Bi2Sr2Ca1Cu2Oy and Bi2Sr1.75Ca0.25CuOy

    International Nuclear Information System (INIS)

    Holesinger, T.G.; Miller, D.J.; Viswanathan, H.K.; Chumbley, L.S.

    1993-01-01

    The solidification processes for the compositions Bi 2 Sr 2 CaCu 2 O y (2212) and Bi 2 Sr 1.75 Ca 0.25 CuO y (2201) were determined as a function of oxygen partial pressure. During solidification in argon, the superconducting phases were generally not observed to form for either composition. In both cases, the solidus is lowered to approximately 750 degree C. Solidification of Bi 2 Sr 1.75 Ca 0.25 CuO y in Ar resulted in a divorced eutectic structure of Bi 2 Sr 2-x Ca x O y (22x) and Cu 2 O while solidification of Bi 2 Sr 2 CaCu 2 O y in Ar resulted in a divorced eutectic structure of Bi 2 Sr 3-x Ca x O y (23x) and Cu 2 O. Solidification of Bi 2 Sr 1.75 Ca 0.25 CuO y in O 2 resulted in large grains of 2201 interspersed with small regions containing the eutectic structure of 22x and CuO/Cu 2 O. Solidification of Bi 2 Sr 2 CaCu 2 O y in partial pressures of 1%, 20%, and 100% oxygen resulted in multiphase samples consisting of 2212, 2201, some alkaline-earth cuprates, and both divorced eutectic structures found during solidification in Ar. For both compositions, these latter structures can be attributed to oxygen deficiencies present in the melt regardless of the overpressure of oxygen. These eutectic structures are unstable and convert into the superconducting phases during subsequent anneals in oxygen. The formation process of the 2212 phase during solidification from the melt was determined to proceed through an intermediate state involving the 2201 phase

  2. Sr isotope variations in the Carnian-Norian succession at Pizzo Mondello, Sicani Mountains, Sicily

    Science.gov (United States)

    Onoue, T.; Yamashita, K.; Rigo, M.; Abate, B.

    2017-12-01

    The Norian stage in the Late Triassic is exceptionally long (23 Myr) and was subdivided into three substages: the Lacian, Alaunian, and Sevatian. In order to infer the Norian environmental changes in the western Tethys Ocean, the stratigraphic variations of 87Sr/86Sr in the Upper Triassic limestone succession in Sicily were examined. The Pizzo Mondello section studied here mainly consists of a pelagic carbonate sequence of the Scillato Formation, and ranges in age from Tuvalian (late Carnian) to Rhaetian. The Scillato Formation represents a deep-water pelagic facies deposited along the Sicanian Basin in the western Tethys Ocean. We selected fine-grained limestone samples from both the microfacies of lime-mudstone and wackestone to approximate the primary 87Sr/86Sr signature of the limestone beds. The 87Sr/86Sr values are relatively constant in the Tuvalian and Lacian (early Norian). However, the remarkable rise in 87Sr/86Sr occurred across the Lacian-Alaunian (early-middle Norian) transition. Variations in 87Sr/86Sr values show an increasing trend in 87Sr/86Sr from 0.7077 at the base of Lacian to 0.7080 in the Sevatian (late Norian). In the Sevatian, the 87Sr/86Sr ratios display a sudden negative excursion toward lower values and show a relatively quick recovery to pre-excursion 87Sr/86Sr ratios. Korte et al. (2003) suggested that the rise in the 87Sr/86Sr values from the middle Carnian to the late Norian coincide with the Cimmerian orogeny. Our new 87Sr/86Sr data from the Pizzo Mondello section reveal a comparable trend, with a sharp increase in 87Sr/86Sr within the Alaunian, suggesting the rapid uplift and erosion in the Cimmerian Mountains at this time. The cause of the 87Sr/86Sr excursion in the Sevatian remains uncertain. However, the biostratigraphic record of conodonts suggests that a morphological evolution towards platform-less elements occurred with the beginning of the Sr-isotope excursion.

  3. Inventory and vertical migration of {sup 90}Sr fallout and {sup 137}Cs/{sup 90}Sr ratio in Spanish mainland soils

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, M. [Department Nuclear Engineering and Fluid Mechanics, University of the Basque, Country (UPV/EHU), Alda Urquijo s/n, E-48013 Bilbao (Spain); Romero, L.M. [CIEMAT, Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Av. Complutense 22, 28040 Madrid (Spain); Idoeta, R. [Department Nuclear Engineering and Fluid Mechanics, University of the Basque, Country (UPV/EHU), Alda Urquijo s/n, E-48013 Bilbao (Spain); Olondo, C., E-mail: kontxi.olondo@ehu.es [Department Nuclear Engineering and Fluid Mechanics, University of the Basque, Country (UPV/EHU), Alda Urquijo s/n, E-48013 Bilbao (Spain); Valino, F. [CIEMAT, Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Av. Complutense 22, 28040 Madrid (Spain); Legarda, F. [Department Nuclear Engineering and Fluid Mechanics, University of the Basque, Country (UPV/EHU), Alda Urquijo s/n, E-48013 Bilbao (Spain)

    2011-11-15

    In this paper the inventory of {sup 90}Sr in 34 points distributed along the Spanish peninsular territory is presented. Obtained values range between 173 Bq/m{sup 2} and 2047 Bq/m{sup 2}. From these data set and those {sup 137}Cs data obtained in a previous work the {sup 137}Cs/{sup 90}Sr activity ratio has been established, laying this value between 0.9 and 3.6. Also the migration depth of both radionuclides has been analysed obtaining for {sup 137}Cs an average value 57% lower than that obtained for {sup 90}Sr. Additionally, this paper presents the results obtained in 11 sampling points in which the activity vertical profile has been measured. These profiles have been analysed to state the behaviour of strontium in soils and after, by using a convective-diffusive model, the parameters of the model which governs the vertical migration of {sup 90}Sr in the soil, v (apparent convection velocity) and D (apparent diffusion coefficient) have been evaluated. Mean values obtained are 0.20 cm/year and 3.67 cm{sup 2}/year, respectively. - Highlights: > Measured {sup 90}Sr activity in Spanish mainland, being within a range of [173, 2047] Bq/m{sup 2}, with a mean value of 793 Bq/m{sup 2}. > Compared the migration capacity of {sup 137}Cs and {sup 90}Sr in the same soils. > {sup 90}Sr shows a unique behaviour tendency in soil. > The parameters which govern the applied model have been obtained for the analysed profiles. > Analysed those parameters' values also reflects this unique tendency.

  4. Comparing subjective well-being and health-related quality of life of Australian drug users in treatment in regional and rural Victoria.

    Science.gov (United States)

    Miller, Peter G; Hyder, Shannon; Zinkiewicz, Lucy; Droste, Nicolas; Harris, Jane B

    2014-11-01

    The aim of this study is to examine the self-reported subjective well-being and health-related quality of life (HRQOL) of alcohol and other drug users and to examine whether subjective well-being in this sample would be predicted by either HRQOL and/or severity of dependence. A cross-sectional survey was conducted of 201 Victorian substance users in individual targeted outpatient treatment for a variety of types of substance use. Participants were administered an interview, including the personal well-being index, the SF-8 health survey and the severity of dependence scale, in order to assess subjective well-being, the mental health component of HRQOL and severity of drug dependence respectively. Subjective well-being was predicted by mental health aspects of HRQOL (sr(2)  = 0.03) and by employment (sr(2)  = 0.05), rather than by severity of dependence [F(5, 146) = 5.60, P well-being than do the general population. Subjective well-being was predicted by mental aspects of HRQOL and not by severity of drug dependence or by physical aspects of HRQOL. Treatment which aims to improve substance users' well-being should include mental health interventions and pathways to employment. © 2014 Australasian Professional Society on Alcohol and other Drugs.

  5. Séries de problèmes dans une tradition d'enseignement des mathématiques en Hongrie au 20e siècle1

    Directory of Open Access Journals (Sweden)

    Gosztonyi Katalin

    2015-01-01

    Full Text Available Dans cet article, nous discutons l'intérêt d'étudier des « séries de problèmes » pour la caractérisation d'une tradition d'enseignement des mathématiques en Hongrie au 20e siècle. Dans la partie 1, nous résumons le contexte historique et les principes partagés dans cette tradition sur les mathématiques et leur enseignement. Dans la partie 2, nous étudions plus en détail un texte d'un membre de cette communauté, un extrait du Jeux avec l'infini de Rózsa Péter, qui nous servira de modèle pour les analyses ultérieures. Dans la partie 3, nous présentons différents documents liés à la réforme de l'enseignement des mathématiques dirigée par Tamás Varga dans les décennies 1960 et 1970, cette réforme étant considérée comme une étape significative dans l'histoire de cette « tradition hongroise ». Nous tenterons de montrer qu'une réflexion sur la mise en ordre des problèmes joue un rôle crucial dans la structuration de ces textes divers, écrits souvent dans une forme narrative et quasi-littéraire ; et que l'étude des « séries de problèmes » présentées dans ces textes peut apporter une contribution importante à la caractérisation de la tradition en question.

  6. Cs-137 and Sr-90 level in diary products

    International Nuclear Information System (INIS)

    Petukhov, V.L.; Dukhanov, Y.A.; Sevryuk, I.Z.; Patrashkov, S.A.; Korotkevich, O.S.; Gorb, T.S.; Petukhov, I.V.

    2003-01-01

    About 70% of radioactive substances fell on the territory of the Byelorussian Republic after the Chernobyl Atom Power Station Disaster. Cs-137 and Sr-90 accumulation dynamics was studied in milk of the cows from the highest polluted Braginsky area. 408 milk samples of Black and White cows were investigated. In 1995 average Cs-137 and Sr-90 levels were 61.00 and 3.73 Bk/dm 3 respectively. Cs-137 and Sr-90 levels exceeded Byelorussian Republic upper limits RDU - 96 in 10 and 50% of milk samples respectively. After 5 years (by 2000) Cs-137 and Sr-90 levels had become almost 3 and 2 times less (21.70 Bk/dm 3 and 1.72 Bk/dm 3 respectively). Cs-137 and Sr-90 levels exceeded RDU - 96 in 1.5 and 5.5% of milk samples respectively. In the same periods Cs-137 and Sr-90 levels were 7 and 2 times higher than the similar indexes in the relatively clean Novosibirsk area. Thus, radioactive element levels in milk of Black and White cows of the Byelorussian Republic decreased significantly for the past years. (authors)

  7. Nonstoichiometry and stability in water of undoped SrCeO3

    Directory of Open Access Journals (Sweden)

    Jurado, J. R.

    2003-10-01

    Full Text Available Strontium cerate is the parent phase of an important class of proton-conducting perovskites with various potential technological applications. Phase formation and structure of SrCeO3 with Sr:Ce nonstoichiometry have been investigated for the series, Sr1±xCeO3±δ (0.98 ≤ x ≤ 1.04. Analyses by EPMA (electron probe micro analysis and X-ray diffraction (XRD indicate that, for samples sintered at 1350°C, the main phase is Sr-rich for all x. The accommodation of excess SrO in the bulk phase and/or intergranular regions is discussed. The stability of nominally stoichiometric SrCeO3 was examined in an atmosphere of high water vapour partial pressure (pH2O for 2 hours, degrading to Sr(OH2.H2O and CeO2 for pH2O ≥ 3.6atm.La fase SrCeO3 da origen a una importante familia de perovskitas conductoras protónicas con potenciales aplicaciones tecnológicas. En este trabajo se estudia la formación de la fase y la estructura de SrCeO3 con la relación Sr:Ce no estequiométrica para la serie Sr1±xCeO3±δ (0.98 ≤ x ≤ 1.04. Los análisis por microsonda (EPMA y difracción de rayos X (DRX indican que en las muestras sinterizadas a 1350°C, la fase principal es rica en estroncio para todo valor de x. Se discute la posible ubicación del exceso de SrO tanto en la región intergranular como en el propio grano. También se examina la estabilidad de la composición con estequiometría nominal SrCeO3 en una atmosfera con una alta presión de vapor de agua (pH2O, observándose que la degradación a Sr(OH2.H2O y CeO2 ocurre a pH2O ≥ 3.6atm (expuesto durante 2 horas.

  8. Targeting SR-BI for cancer diagnostics, imaging and therapy

    Directory of Open Access Journals (Sweden)

    Maneesha Amrita Rajora

    2016-09-01

    Full Text Available Scavenger receptor class B type I (SR-BI plays an important role in trafficking cholesteryl esters between the core of high density lipoprotein and the liver. Interestingly, this integral membrane protein receptor is also implicated in the metabolism of cholesterol by cancer cells, whereby overexpression of SR-BI has been observed in a number of tumours and cancer cell lines, including breast and prostate cancers. Consequently, SR-BI has recently gained attention as a cancer biomarker and exciting target for the direct cytosolic delivery of therapeutic agents. This brief review highlights these key developments in SR-BI-targeted cancer therapies and imaging probes. Special attention is given to the exploration of high density lipoprotein nanomimetic platforms that take advantage of upregulated SR-BI expression to facilitate targeted drug-delivery and cancer diagnostics, and promising future directions in the development of these agents.

  9. Training effect of exchange bias in La0.67Sr0.33MnO3/SrTiO3 superlattice

    International Nuclear Information System (INIS)

    Zhu, S J; Zhao, B R; Xu, B; Zhu, B Y; Cao, L X; Qiu, X G

    2008-01-01

    The training effect of exchange bias has been observed in the superlattice consisting of ferromagnetic La 0.67 Sr 0.33 MnO 3 and non-magnetic SrTiO 3 layers. The exchange field shows an approximately power-law decrease with an increase in the number of hysteresis loop measurements. The vertical shift of the hysteresis loop reveals the existence of the net uncompensated spins at the interface between the La 0.67 Sr 0.33 MnO 3 and the SrTiO 3 layers. The irreversibility of magnetization measurements gives clear evidence that the interfacial spins will be frozen at low temperature. It is suggested that the frozen uncompensated spins at the interface are responsible for the shift of the hysteresis loop and the training effect of exchange bias might be a result of the relaxation process of those interfacial spins when the superlattice is consecutively field-cycled.

  10. MIPyMEs Industriales de Colombia y México: Factores que dificultan o facilitan su desarrollo 2000-2013

    OpenAIRE

    Luna Rincón, Jonny Eliecer; Vargas Pulino, William Ernesto

    2017-01-01

    La presente investigación aborda los diferentes puntos de vista teórico-prácticos de los factores productivos (trabajo, tierra, capital y tecnología) y de entorno (Política económica que a su vez se divide en Política Monetaria, Política de Rentas, Política Fiscal, Política Cambiaria y Política Exterior) que facilitan o dificultan el desarrollo económico de las MIPyMEs del sector industrial de Colombia y México en el periodo comprendido del año 2000 al 2013, tomando como referencia las teoría...

  11. Sr isotope zoning in plagioclase from andesites at Cabo De Gata, Spai

    DEFF Research Database (Denmark)

    Waight, Tod Earle; Tørnqvist, Jakob

    2018-01-01

    Plagioclase crystals in andesites from the Cabo De Gata region show generally radiogenic Sr isotope compositions and consistent core to rim increases in 87Sr/86Sr that are indicative of open system processes in the lithosphere and crustal contamination during crystallization. High-grade metamorphic...... rocks of the Alpujárride and Nevado-Filábride complexes represent the most likely crustal contaminants. The plagioclases are characterized by subtly zoned and resorbed calcic cores (An73-86). These cores also have radiogenic 87Sr/86Sr (0.7127-0.7129), although less radiogenic than plagioclase rims......, groundmass plagioclase and whole rock compositions (up to 87Sr/86Sr = 0.7135). These cores are interpreted to represent early crystallization of plagioclase from hydrous melts emplaced into the lower crust. The parental melts to these andesites must therefore have already inherited their radiogenic Sr...

  12. 87Sr/86Sr and 18O/16O ratios, interstitial water chemistry and diagenesis in deep-sea carbonate sediments of the Ontong Java Plateau

    International Nuclear Information System (INIS)

    Elderfield, H.; Oldfield, R.K.; Hawkesworth, C.J.

    1982-01-01

    Interstitial waters and sediments from DSDP sites 288 and 289 contain information on the chemistry and diagenesis of carbonate in deep-sea sediments and on the role of volcanic matter alteration processes. Sr/Ca ratios are species dependent in unaltered foraminifera from site 289 and atom ratios exceed those predicted by distribution coefficient data. During diagenesis Sr/Ca ratios of carbonates decrease and reach the theoretical distribution at a depth which is identical to the depth of Sr isotopic equilibration, where 87 Sr/ 86 Sr ratios of interstitial waters and carbonates converge. Mg/Ca ratios in the carbonates do not increase with depth as found in some other DSDP sites, possibly because of diagenetic re-equilibration with interstitial waters showing decreasing Mg 2+ /Ca 2+ ratios with depth due to Ca input and Mg removal by alteration of volcanic matter. Interstitial 18 O/ 16 O ratios increase with depth at site 289 to delta 18 O = 0.67 per thousand (SMOW), reflecting carbonate recrystallization at elevated temperatures, the first recorded evidence of this effect in interstitial waters. Interstitial Sr 2+ concentrations reach high levels, up to 1 mM, chiefly because of carbonate recrystallization. However, 87 Sr/ 86 Sr ratios decrease from 0.7092 to less than 0.7078, lower than for contemporaneous sea water, showing that there is a volcanic input of strontium at depth. (author)

  13. Automated Inventory and Monitoring of the ALICE HLT Cluster Resources with the SysMES Framework

    International Nuclear Information System (INIS)

    Ulrich, J; Lara, C; Böttger, S; Kebschull, U; Haaland, Ø; Röhrich, D

    2012-01-01

    The High-Level-Trigger (HLT) cluster of the ALICE experiment is a computer cluster with about 200 nodes and 20 infrastructure machines. In its current state, the cluster consists of nearly 10 different configurations of nodes in terms of installed hardware, software and network structure. In such a heterogeneous environment with a distributed application, information about the actual configuration of the nodes is needed to automatically distribute and adjust the application accordingly. An inventory database provides a unified interface to such information. To be useful, the data in the inventory has to be up to date, complete and consistent. Manual maintenance of such databases is error-prone and data tends to become outdated. The inventory module of the ALICE HLT cluster overcomes these drawbacks by automatically updating the actual state periodically and, in contrast to existing solutions, it allows the definition of a target state for each node. A target state can simply be a fully operational state, i.e. a state without malfunctions, or a dedicated configuration of the node. The target state is then compared to the actual state to detect deviations and malfunctions which could induce severe problems when running the application. The inventory module of the ALICE HLT cluster has been integrated into the monitoring and management framework SysMES in order to use existing functionality like transactionality and monitoring infrastructure. Additionally, SysMES allows to solve detected problems automatically via its rule-system. To describe the heterogeneous environment with all its specifics, like custom hardware, the inventory module uses an object-oriented model which is based on the Common Information Model. The inventory module provides an automatically updated actual state of the cluster, detects discrepancies between the actual and the target state and is able to solve detected problems automatically. This contribution presents the current implementation

  14. Novel approaches for 90Sr analyses in contaminated environmental samples

    International Nuclear Information System (INIS)

    Kavasi, N.; Sahoot, S.K.; Area, H.; Aono, T.

    2016-01-01

    Radioactive strontium isotopes are generated with high cumulative fission yield (5-6 %) during thermal neutron fission in a nuclear reactor. The physical half-life of 89 Sr (50.52 d) is short but that of 90 Sr (28.8 y) is long enough to generate radioecological repercussions. 90 Sr has a long-lasting biological half-life (∼18 y) in the human body, due to its chemical similarity to calcium the importance of 90 Sr analysis is emphasized in case of a nuclear disaster. The world-wide spread of 90 Sr, as a background, is derived from the global atmospheric fallout contributed by large-scale atmospheric nuclear weapons tests conducted from 1945. In case of local contamination, nuclear accidents are not the only source of 90 Sr isotope, misconducted underground nuclear weapon tests; improper handling of by-products of nuclear weapon production or normal operation of nuclear facilities (e.g. reprocessing plants) can be taken into account

  15. Effectiveness of Sr-binders tested using an in vitro model

    International Nuclear Information System (INIS)

    Hansen, Hanne S.; Eikelman, Margrethe; Hove, Knut

    2008-01-01

    Full text: The radioisotope 90 Sr is a fission product that in biological systems will behave like calcium and accumulate in bone. Because of the dose effect and the long biological half life of radiostrontium in humans the best countermeasure is to avoid absorption. Low levels of radiostrontium in food products are therefore necessary. To obtain food products, particularly milk, with low radiostrontium levels, the use of Sr-binders in animals may be required. We have tested a number of potential Sr-binders that may be used in animal production. Preliminary studies testing the Sr-binding effect of several compounds in goats demonstrated that only zeolite A(Na) and zeolite P would be of practical interest. Given at a rate of up to 30 g/d the Sr transfer to milk was reduced by 40%. However, because of the chemical properties of the zeolites, they may also bind other cations like Ca, Mg, Cu and Zn, all important minerals for animals. We have therefore tested the binding kinetics of Sr, Ca and Mg by the zeolites in rumen liquid from cows. We used 85 Sr to measure Sr binding and the stable elements of Ca and Mg naturally present in the rumen liquid to measure the binding of these minerals. In the rumen liquid mixture the pH was varied to simulate the pH variation in the digestive system of ruminants and the binding of the minerals to the zeolites were measured at each step. The time dependant 85 Sr binding showed that zeolite A(Na), at 0.5% in rumen liquid, pH 7.3, bound 98% of the 85 Sr already after 10 min. This proportion of Sr binding was persistent for the tested period of 24 h. The zeolite P at 0.5% in rumen liquid, pH 7.3, bound ca 85% and had a similar time dependant behavior. When pH was reduced to 2.5, similar to the pH in the abomasum, no Sr was bound to the zeolites. This was also the case at pH 3 and 4. At pH 5 ca 10% of the Sr was bound. Theses levels of pH simulated the conditions in the small intestine. To simulate the conditions in the large intestine

  16. Electronic parameters of Sr2Nb2O7 and chemical bonding

    DEFF Research Database (Denmark)

    Atuchin, V.V.; Grivel, Jean-Claude; Korotkov, A.S.

    2008-01-01

    /2)) and Delta(O-Sr) = BE(O 1s)-BE(Sr 3d(5/2)), were used to characterize the valence electron transfer on the formation of the Nb-O and Sr-O bonds. The chemical bonding effects were considered on the basis of our XPS results for Sr2Nb2O7 and earlier published structural and XPS data for other Sr- or Nb...

  17. Quenched Magnon excitations by oxygen sublattice reconstruction in (SrCuO 2) n /(SrTiO 3) 2 superlattices

    NARCIS (Netherlands)

    Dantz, M.; Pelliciari, J.; Samal, D.; Bisogni, V.; Huang, Y.; Olalde-Velasco, P.; Strocov, V. N.; Koster, G.; Schmitt, T.

    2016-01-01

    The recently discovered structural reconstruction in the cuprate superlattice (SrCuO 2) n /(SrTiO 3) 2 has been investigated across the critical value of n = 5 using resonant inelastic x-ray scattering (RIXS). We find that at the critical value of n, the cuprate layer remains largely in the

  18. Precessional control of Sr ratios in marginal basins during the Messinian Salinity Crisis?

    Science.gov (United States)

    Topper, R. P. M.; Lugli, S.; Manzi, V.; Roveri, M.; Meijer, P. Th.

    2014-05-01

    Based on 87Sr/86Sr data of the Primary Lower Gypsum (PLG) deposits in the Vena del Gesso basin—a marginal basin of the Mediterranean during the Messinian Salinity Crisis—a correlation between 87Sr/86Sr values and precessional forcing has recently been proposed but not yet confirmed. In this study, a box model is set up to represent the Miocene Mediterranean deep basin and a connected marginal basin. Measurements of 87Sr/86Sr in the Vena del Gesso and estimated salinity extrema are used to constrain model results. In an extensive analysis with this model, we assess whether coeval 87Sr/86Sr and salinity fluctuations could have been forced by precession-driven changes in the fresh water budget. A comprehensive set of the controlling parameters is examined to assess the conditions under which precession-driven 87Sr/86Sr variations occur and to determine the most likely setting for PLG formation. Model results show that precession-driven 87Sr/86Sr and salinity fluctuations in marginal basins are produced in settings within a large range of marginal basin sizes, riverine strontium characteristics, amplitudes of precessional fresh water budget variation, and average fresh water budgets of both the marginal and deep basin. PLG deposition most likely occurred when the Atlantic-Mediterranean connection was restricted, and the average fresh water budget in the Mediterranean was significantly less negative than at present day. Considering the large range of settings in which salinities and 87Sr/86Sr fluctuate on a precessional timescale, 87Sr/86Sr variations are expected to be a common feature in PLG deposits in marginal basins of the Mediterranean.

  19. Microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Chaoyong [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); Pan, Fusheng, E-mail: fspan@cqu.edu.cn [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Chongqing Academy of Science and Technology, Chongqing 401123 (China); Zhang, Lei; Pan, Hucheng; Song, Kai; Tang, Aitao [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China)

    2017-01-01

    In this study, as-extruded Mg-Sr alloys were studied for orthopedic application, and the microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys were investigated by optical microscopy, scanning electron microscopy with an energy dispersive X-ray spectroscopy, X-ray diffraction, tensile and compressive tests, immersion test, electrochemical test and cytotoxicity test. The results showed that as-extruded Mg-Sr alloys were composed of α-Mg and Mg{sub 17}Sr{sub 2} phases, and the content of Mg{sub 17}Sr{sub 2} phases increased with increasing Sr content. As-extruded Mg-Sr alloy with 0.5 wt.% Sr was equiaxed grains, while the one with a higher Sr content was long elongated grains and the grain size of the long elongated grains decreased with increasing Sr content. Tensile and compressive tests showed an increase of both tensile and compressive strength and a decrease of elongation with increasing Sr content. Immersion and electrochemical tests showed that as-extruded Mg-0.5Sr alloy exhibited the best anti-corrosion property, and the anti-corrosion property of as-extruded Mg-Sr alloys deteriorated with increasing Sr content, which was greatly associated with galvanic couple effect. The cytotoxicity test revealed that as-extruded Mg-0.5Sr alloy did not induce toxicity to cells. These results indicated that as-extruded Mg-0.5Sr alloy with suitable mechanical properties, corrosion resistance and good cytocompatibility was potential as a biodegradable implant for orthopedic application. - Highlights: • Biodegradable as-extruded Mg-Sr alloys were fabricated. • Microstructure of alloys changed with increasing Sr content. • Mechanical properties of alloys could be controlled by adjusting the Sr content. • Corrosion properties of alloys decreased with increasing Sr content. • As-extruded Mg-0.5Sr alloy was potential for orthopedic application.

  20. μ+SR Investigation of the Shastry-Sutherland Compound SrCu2(BO3)2

    Science.gov (United States)

    Sassa, Y.; Wang, S.; Sugiyama, J.; Amato, A.; Rønnow, H. M.; Rüegg, C.; Månsson, M.

    In this study we have investigated the low-dimensional correlated spin system SrCu2(BO3)2 using ambient-pressure muon spin rotation/relaxation (μ+SR). The zero-field data are similar to previously published data, but in addition, they give an even clearer sign of the two low-temperature transitions (T1 ≈ 3 and T2 ≈ 7 K), which is fully consistent with inelastic neutron scattering (INS) measurements. Longitudinal field (LF) data clearly show that the copper spins are highly dynamic and a saturation of the low-temperature relaxation rate indicate that these are indeed two-dimensional (2D) quantum spin fluctuations.

  1. Systèmes coopératifs hybride Satellite-Terrestre : analyse de performance et dimensionnement du système

    OpenAIRE

    Sreng, Sokchenda

    2012-01-01

    Les systèmes de communications par satellite sont utilisés dans le contexte de la radiodiffusion, de la navigation, du sauvetage et du secours aux sinistrés, car ils permettent de fournir des services sur une large zone de couverture. Cependant, cette zone de couverture est limitée par l'effet de masquage provoqué par des obstacles qui bloquent la liaison directe entre le satellite et un utilisateur terrestre. L'effet de masquage devient plus sévère en cas de satellites à faibles angles d'élé...

  2. Surface structural reconstruction of SrVO3 thin films on SrTiO3 (001)

    Science.gov (United States)

    Wang, Gaomin; Saghayezhian, Mohammad; Chen, Lina; Guo, Hangwen; Zhang, Jiandi

    Paramagnetic metallic oxide SrVO3>(SVO) is an itinerant system known to undergo thickness-induced metal-insulator-transition (MIT) in ultrathin film form, which makes it a prototype system for the study of the mechanism behind metal-insulator-transition like structure distortion, electron correlations and disorder-induced localization. We have grown SrVO3 thin film with atomically flat surface through the layer-by-layer deposition by laser Molecular Beam Epitaxy (laser-MBE) on SrTiO3 (001) surface. Low Energy Electron Diffraction (LEED) measurements reveal that there is a (√2X √2) R45°surface reconstruction independent of film thickness. By using LEED-I(V) structure refinement, we determine the surface structure. In combination with X-ray Photoelectron Spectroscopy (XPS) and Scanning Tunneling Microscopy (STM), we discuss the implication on the MIT in ultrathin films below 2-3 unit cell thickness. This work is supported by the National Science Foundation under the NSF EPSCoR Cooperative Agreement No. EPS-1003897 with additional support from the Louisiana Board of Regents.

  3. The coprecipitation of Sr2+ with calcite at 250C and 1 atm

    International Nuclear Information System (INIS)

    Pingitore, N.E. Jr.; Eastman, M.P.

    1986-01-01

    The incorporation of Sr 2+ into calcite at earth surface aqueous conditions is affected by the absolute concentration of Sr 2+ , the presence of Ba 2+ and NaCl in the solution and the rate of precipitation. At solution ratios (molar) of Sr 2+ to Ca 2+ in the low 10 -3 range, which yield calcites with several hundred ppm Sr 2+ , kappasub(calcite) sup(Sr) typically assumes a value between 0.10 and 0.20. Above these concentrations the value of kappasub(calcite) sup(Sr) drops to approximately 0.06. Furthermore, if minor amounts of Ba 2+ or large amounts of Na + (0.48 M) are added to a dilute Sr 2+ solution, a value around 0.06 for kappasub(calcite)sup(Sr) is found. This 'strontium concentration effect' and the associated 'competitive cation effect' suggest that small amounts of Sr 2+ may be incorporated into a limited number of nonlattice sites in calcite. Incorporation of Sr 2+ into these sites, presumably defects, noticeably affects kappasub(calcite)sup(Sr) only at low Sr 2+ concentrations and in the absence of competition from other large cations. An increase in kappasub(calcite)sup(Sr) with rate of precipitation, qualitatively similar to that found in other studies, was observed only when precipitation times were decreased from days to hours. For many geologic settings a partition coefficient for Sr 2+ into calcite of 0.06 appears appropriate, but there are situations - very low Sr 2+ concentrations, the presence of Mg 2+ , and fast precipitation rates - in which a larger value might better approximate natural partitioning. (author)

  4. Carboniferous climate teleconnections archived in coupled bioapatite δ18OPO4 and 87Sr/86Sr records from the epicontinental Donets Basin, Ukraine

    Science.gov (United States)

    Montanez, Isabel P.; Osleger, Dillon J.; Chen, J.-H.; Wortham, Barbara E.; Stamm, Robert G.; Nemyrovska, Tamara I.; Griffin, Julie M.; Poletaev, Vladislav I.; Wardlaw, Bruce R.

    2018-01-01

    Reconstructions of paleo-seawater chemistry are largely inferred from biogenic records of epicontinental seas. Recent studies provide considerable evidence for large-scale spatial and temporal variability in the environmental dynamics of these semi-restricted seas that leads to the decoupling of epicontinental isotopic records from those of the open ocean. We present conodont apatite δ18OPO4 and 87Sr/86Sr records spanning 24 Myr of the late Mississippian through Pennsylvanian derived from the U–Pb calibrated cyclothemic succession of the Donets Basin, eastern Ukraine. On a 2 to 6 Myr-scale, systematic fluctuations in bioapatite δ18OPO4 and 87Sr/86Sr broadly follow major shifts in the Donets onlap–offlap history and inferred regional climate, but are distinct from contemporaneous more open-water δ18OPO4 and global seawater Sr isotope trends. A −1 to −6‰ offset in Donets δ18OPO4 values from those of more open-water conodonts and greater temporal variability in δ18OPO4 and 87Sr/86Sr records are interpreted to primarily record climatically driven changes in local environmental processes in the Donets sea. Systematic isotopic shifts associated with Myr-scale sea-level fluctuations, however, indicate an extrabasinal driver. We propose a mechanistic link to glacioeustasy through a teleconnection between high-latitude ice changes and atmospheric pCO2 and regional monsoonal circulation in the Donets region. Inferred large-magnitude changes in Donets seawater salinity and temperature, not archived in the more open-water or global contemporaneous records, indicate a modification of the global climate signal in the epicontinental sea through amplification or dampening of the climate signal by local and regional environmental processes. This finding of global climate change filtered through local processes has implications for the use of conodont δ18OPO4 and 87Sr/86Sr values as proxies of paleo-seawater composition, mean temperature, and glacioeustasy.

  5. Carboniferous climate teleconnections archived in coupled bioapatite δ18OPO4 and 87Sr/86Sr records from the epicontinental Donets Basin, Ukraine

    Science.gov (United States)

    Montañez, Isabel P.; Osleger, Dillon J.; Chen, Jitao; Wortham, Barbara E.; Stamm, Robert G.; Nemyrovska, Tamara I.; Griffin, Julie M.; Poletaev, Vladislav I.; Wardlaw, Bruce R.

    2018-06-01

    Reconstructions of paleo-seawater chemistry are largely inferred from biogenic records of epicontinental seas. Recent studies provide considerable evidence for large-scale spatial and temporal variability in the environmental dynamics of these semi-restricted seas that leads to the decoupling of epicontinental isotopic records from those of the open ocean. We present conodont apatite δ18OPO4 and 87Sr/86Sr records spanning 24 Myr of the late Mississippian through Pennsylvanian derived from the U-Pb calibrated cyclothemic succession of the Donets Basin, eastern Ukraine. On a 2 to 6 Myr-scale, systematic fluctuations in bioapatite δ18OPO4 and 87Sr/86Sr broadly follow major shifts in the Donets onlap-offlap history and inferred regional climate, but are distinct from contemporaneous more open-water δ18OPO4 and global seawater Sr isotope trends. A -1 to -6‰ offset in Donets δ18OPO4 values from those of more open-water conodonts and greater temporal variability in δ18OPO4 and 87Sr/86Sr records are interpreted to primarily record climatically driven changes in local environmental processes in the Donets sea. Systematic isotopic shifts associated with Myr-scale sea-level fluctuations, however, indicate an extrabasinal driver. We propose a mechanistic link to glacioeustasy through a teleconnection between high-latitude ice changes and atmospheric pCO2 and regional monsoonal circulation in the Donets region. Inferred large-magnitude changes in Donets seawater salinity and temperature, not archived in the more open-water or global contemporaneous records, indicate a modification of the global climate signal in the epicontinental sea through amplification or dampening of the climate signal by local and regional environmental processes. This finding of global climate change filtered through local processes has implications for the use of conodont δ18OPO4 and 87Sr/86Sr values as proxies of paleo-seawater composition, mean temperature, and glacioeustasy.

  6. SYRMEP Tomo Project: a graphical user interface for customizing CT reconstruction workflows.

    Science.gov (United States)

    Brun, Francesco; Massimi, Lorenzo; Fratini, Michela; Dreossi, Diego; Billé, Fulvio; Accardo, Agostino; Pugliese, Roberto; Cedola, Alessia

    2017-01-01

    When considering the acquisition of experimental synchrotron radiation (SR) X-ray CT data, the reconstruction workflow cannot be limited to the essential computational steps of flat fielding and filtered back projection (FBP). More refined image processing is often required, usually to compensate artifacts and enhance the quality of the reconstructed images. In principle, it would be desirable to optimize the reconstruction workflow at the facility during the experiment (beamtime). However, several practical factors affect the image reconstruction part of the experiment and users are likely to conclude the beamtime with sub-optimal reconstructed images. Through an example of application, this article presents SYRMEP Tomo Project (STP), an open-source software tool conceived to let users design custom CT reconstruction workflows. STP has been designed for post-beamtime (off-line use) and for a new reconstruction of past archived data at user's home institution where simple computing resources are available. Releases of the software can be downloaded at the Elettra Scientific Computing group GitHub repository https://github.com/ElettraSciComp/STP-Gui.

  7. Interim process report for the safety assessment SR-Can

    International Nuclear Information System (INIS)

    Sellin, Patrick

    2004-08-01

    This report is a documentation of buffer processes identified as relevant to the long-term safety of a KBS-3 repository. The report is part of the interim reporting of the safety assessment SR-Can, see further the Interim main report. The final SR-Can reporting will support SKB's application to build an Encapsulation plant for spent nuclear fuel and is to be produced in 2006. The purpose of this report is to document the scientific knowledge of the processes to a level required for an adequate treatment in the safety assessment. The documentation is thus from a scientific point of not exhaustive since such a treatment is neither necessary for the purposes of the safety assessment nor possible within the scope of an assessment. The purpose is further to determine the handling of each process in the safety assessment and to demonstrate how uncertainties are taken care of, given the suggested handling. The process documentation in the SR 97 version of the Process report is a starting point for this SR-Can interim version. As further described in the Interim main report, the list of relevant processes has been reviewed and slightly extended by comparison to other databases. Furthermore, the backfill has been included as a system part of its own, rather than being described together with the buffer as in SR 97. Apart from giving an interim account of the documentation and handling of buffer processes in SR-Can, this report is meant to serve as a template for the forthcoming documentation of processes occurring in other parts of the repository system. A complete list of processes can be found in the Interim FEP report for the safety assessment SR-Can. All material presented in this document is preliminary in nature and will possibly be updated as the SR-Can project progresses

  8. Interim process report for the safety assessment SR-Can

    Energy Technology Data Exchange (ETDEWEB)

    Sellin, Patrick (ed.)

    2004-08-01

    This report is a documentation of buffer processes identified as relevant to the long-term safety of a KBS-3 repository. The report is part of the interim reporting of the safety assessment SR-Can, see further the Interim main report. The final SR-Can reporting will support SKB's application to build an Encapsulation plant for spent nuclear fuel and is to be produced in 2006. The purpose of this report is to document the scientific knowledge of the processes to a level required for an adequate treatment in the safety assessment. The documentation is thus from a scientific point of not exhaustive since such a treatment is neither necessary for the purposes of the safety assessment nor possible within the scope of an assessment. The purpose is further to determine the handling of each process in the safety assessment and to demonstrate how uncertainties are taken care of, given the suggested handling. The process documentation in the SR 97 version of the Process report is a starting point for this SR-Can interim version. As further described in the Interim main report, the list of relevant processes has been reviewed and slightly extended by comparison to other databases. Furthermore, the backfill has been included as a system part of its own, rather than being described together with the buffer as in SR 97. Apart from giving an interim account of the documentation and handling of buffer processes in SR-Can, this report is meant to serve as a template for the forthcoming documentation of processes occurring in other parts of the repository system. A complete list of processes can be found in the Interim FEP report for the safety assessment SR-Can. All material presented in this document is preliminary in nature and will possibly be updated as the SR-Can project progresses.

  9. Synthesis and structure of Sr{sub 2}Pd{sub 2}In and Sr{sub 2}Pt{sub 2}In

    Energy Technology Data Exchange (ETDEWEB)

    Muts, I. [Inst. fuer Anorganische und Analytische Chemie, Univ. Muenster (Germany); Inorganic Chemistry Dept., Ivan Franko National Univ. of Lviv (Ukraine); Nilges, T.; Rodewald, U.C.; Poettgen, R. [Inst. fuer Anorganische und Analytische Chemie, Univ. Muenster (Germany); Zaremba, V.I. [Inorganic Chemistry Dept., Ivan Franko National Univ. of Lviv (Ukraine)

    2007-12-15

    The new intermetallic compounds Sr{sub 2}Pd{sub 2}In and Sr{sub 2}Pt{sub 2}In were synthesized from the elements in sealed tantalum tubes in a water-cooled sample chamber of an induction furnace. Both indides crystallize with the HT-Pr{sub 2}Co{sub 2}Al-type structure: C2/c, a = 1048.7(2), b = 603.5(2), c = 830.6(1) pm. {beta} = 103.68(2) , wR2 = 0.0492, 743 F{sup 2} values for Sr{sub 2}Pd{sub 2}In; a = 1026.8(2), b = 599.0(1), c = 830.3(2) pm, {beta} = 103.17(1) , wR2 = 0.0666, 885 F{sup 2} values for Sr{sub 2}Pt{sub 2}In with 25 variables per refinement. The shortest interatomic distances occur for the Pd-In (Pt-In) and Pd-Pd (Pt-Pt) contacts. The strontium atoms are embedded in complex three-dimensional polyanionic networks of compositions [Pd{sub 2}In] and [Pt{sub 2}In]. (orig.)

  10. Uptake indexes of 90Sr in the countries with various nutrition types

    International Nuclear Information System (INIS)

    Knizhnikov, V.N.; Marej, A.N.; Borisov, B.K.; Petukhova, Eh.V.

    1980-01-01

    90 Sr uptake in the human organism in the USSR and a number of countries with a western type of nitrition is studied for the period from 1963 to 1971. The following indexes are presented: the observed ratio (OR), which is 90 Sr in a skeleton/ 90 Sr in a diet pCi/gCa/pCi/gCa. This index depends largely on the level of calcium content in the diet. The index of buildup multiplicity is used to characterize 90 Sr uptake irrespective of calcium content in the diet. These indexes are used to compare 90 Sr uptake in France, USA, USSR, FRG. Factors which affect 90 Sr uptake connected with nutrition peculiarities and 90 Sr form in the diet, are presented

  11. Role river flow for Sr 90 decontamination of polluted territories of Belarus

    International Nuclear Information System (INIS)

    Kudel'skij, A.V.; Smith, J.T.; Zhukova, O.M.; Rudaya, S.M.; Sasina, N.V.

    2002-01-01

    Sr 90 contamination of the water flow Dnepr, Pripyat', Sozh, Besed', Iput' rivers is considered. The dynamics of reducing the average year activities of Sr 90 and the variations of the levels of Sr 90 activities in river water during spring-autumn high water are shown. The results of investigation of Sr 90 activity of the sediments of Pripyat' and Braginka rivers are connected with the second effects of the contamination of the river flowing off Sr 90 during high water period. Sr 90 transfer in composition of the flowing off river during 1990-1995 (from Belarus to Ukraine) is being estimated. (authors)

  12. 90Sr in the skeleton of new-born children and infants

    International Nuclear Information System (INIS)

    Borisov, B.K.

    1980-01-01

    The correlation between 90 Sr content in the skeleton of new-born children and infants and 90 Sr content in the vertebrae spongy tissue of mother, is studied in different countries from 1965 to 1973. The highest indexes of 90 Sr concentration in the bone tissue of new-born children are found to be characteristic of Canada and Norway. The minimum 90 Sr content is observed in Japan. The dynamics of indexes which characterize 90 Sr content in the bone tissue of infants is presented. The peculiarities are conditioned by particular nutrition of an infant nursing and cow milk used as additional food

  13. Myoelectric control of prosthetic hands: state-of-the-art review

    Directory of Open Access Journals (Sweden)

    Geethanjali P

    2016-07-01

    Full Text Available Purushothaman Geethanjali School of Electrical Engineering Department of Control and Automation VIT University, Vellore, Tamil Nadu, India Abstract: Myoelectric signals (MES have been used in various applications, in particular, for identification of user intention to potentially control assistive devices for amputees, orthotic devices, and exoskeleton in order to augment capability of the user. MES are also used to estimate force and, hence, torque to actuate the assistive device. The application of MES is not limited to assistive devices, and they also find potential applications in teleoperation of robots, haptic devices, virtual reality, and so on. The myoelectric control-based prosthetic hand aids to restore activities of daily living of amputees in order to improve the self-esteem of the user. All myoelectric control-based prosthetic hands may not have similar operations and exhibit variation in sensing input, deciphering the signals, and actuating prosthetic hand. Researchers are focusing on improving the functionality of prosthetic hand in order to suit the user requirement with the different operating features. The myoelectric control differs in operation to accommodate various external factors. This article reviews the state of the art of myoelectric prosthetic hand, giving description of each control strategy. Keywords: EMG, assistive device, amputee, myoelectric control, electric powered, body ­powered, bioelectric signal control

  14. Regularity on absorption and accumulation of 90Sr in yellow-feather broiler (Hypeco)

    International Nuclear Information System (INIS)

    Xu Shiming; Hou Lanxin; Zhao Wenhu; Li Xia; Yang Zhongyuan

    1996-02-01

    The feeding experiment was carried for yellow-feather broiler (Hypeco) with 90 Sr[NO 3 ] 2 having of 1.85 x 10 2 ∼1.85 x 10 5 Bq/chicken to observe the regular pattern of absorption and accumulation of 90 Sr in its organs and tissues. The absorption rate of 90 Sr by oral feeding is very low. The most of 90 Sr is drained away by daily excreta from the body. The half-time of its feeding is within 24 hours. The more 90 Sr is fed, the more 90 Sr is absorbed, however, the uptake rate of 90 Sr is decreasing. The affinity of 90 Sr for bone is very strong and the partition ratio is about 90%∼99%. The absorption coefficient of 90 Sr in organs and tissues of broiler is presented. (2 refs., 9 tabs.)

  15. Potential of Sr isotopic analysis in ceramic provenance studies: Characterisation of Chinese stonewares

    Science.gov (United States)

    Li, Bao-Ping; Zhao, Jian-Xin; Greig, Alan; Collerson, Kenneth D.; Zhuo, Zhen-Xi; Feng, Yue-Xin

    2005-11-01

    We compare the trace element and Sr isotopic compositions of stoneware bodies made in Yaozhou and Jizhou to characterise these Chinese archaeological ceramics and examine the potential of Sr isotopes in provenance studies. Element concentrations determined by ICP-MS achieve distinct characterisation for Jizhou samples due to their restricted variation, yet had limited success with Yaozhou wares because of their large variability. In contrast, 87Sr/86Sr ratios in Yaozhou samples have a very small variation and are all significantly lower than those of Jizhou samples, which show a large variation and cannot be well characterised with Sr isotopes. Geochemical interpretation reveals that 87Sr/86Sr ratios will have greater potential to characterise ceramics made of low Rb/Sr materials such as kaolin clay, yet will show larger variations in ceramics made of high Rb/Sr materials such as porcelain stone.

  16. Potential of Sr isotopic analysis in ceramic provenance studies: Characterisation of Chinese stonewares

    International Nuclear Information System (INIS)

    Li Baoping; Zhao Jianxin; Greig, Alan; Collerson, Kenneth D.; Zhuo Zhenxi; Feng Yuexin

    2005-01-01

    We compare the trace element and Sr isotopic compositions of stoneware bodies made in Yaozhou and Jizhou to characterise these Chinese archaeological ceramics and examine the potential of Sr isotopes in provenance studies. Element concentrations determined by ICP-MS achieve distinct characterisation for Jizhou samples due to their restricted variation, yet had limited success with Yaozhou wares because of their large variability. In contrast, 87 Sr/ 86 Sr ratios in Yaozhou samples have a very small variation and are all significantly lower than those of Jizhou samples, which show a large variation and cannot be well characterised with Sr isotopes. Geochemical interpretation reveals that 87 Sr/ 86 Sr ratios will have greater potential to characterise ceramics made of low Rb/Sr materials such as kaolin clay, yet will show larger variations in ceramics made of high Rb/Sr materials such as porcelain stone

  17. Deposition of 90Sr in bone and the relevant dose

    International Nuclear Information System (INIS)

    Kawamura, Hisao

    1976-01-01

    The deposition of fallout 90 Sr in bone and radiation dose from the nuclide in Japan is reviewed with special reference to (i) the intraskeletal distribution of 90 Sr and reference bone, (ii) bone models for predicting 90 Sr level and (iii) possible problems in applying dose rate factors to Japanese, especially to infants and adolescents. An evidence is presented for the assumption that the ratio of the 90 Sr concentration in a particular bone to that in vertebra will reach the ratio observed for stable strontium under the virtually constant intake of 90 Sr. The importance of surveying 90 Sr levels in different bones is stressed. Observed Ratios (bone/diet) found for Japanese are noticeably lower than those reported for Europeans and Americans. The recently presented model for the retention of alkaline earth elements in man by ICRP will be useful if only adults are concerned. Dose rate factors for 90 Sr in bone should be given as a function of age for the purpose of better estimation of dose commitments. The cumulative absorbed doses to bone tissues calculated with the Palmley-Mays model and with the Spiers model show remarkably higher levels in school children and young adults than the mean level. (auth.)

  18. Effects of lifetime ingestion of 90Sr in beagle dogs

    International Nuclear Information System (INIS)

    Book, S.A.; Spangler, W.L.; Swartz, L.A.

    1982-01-01

    To investigate the effects of lifetime 90 Sr ingestion, fifteen beagle dogs were fed the equivalent of 1.3, 4.0, and 12.0 μCi 90 Sr. Exposures prior to weaning were made by maternal administration of one of the same 90 Sr levels, begining at 21 days of gestation. Median survival was 12.5 years for the 1.3 μCi/day group, 6.5 years for the 4 μCi/day group, and 5.2 years of the 12 μCi/day group, compared to unirradiated control values of 14.5 to 15 years. The normal life span of more than half of the 1.3 μCi/day group is remarkable, considering they ingested 5900 to 7500 μCi 90 Sr during their lifetimes. One of seven 1.3 μCi/day dogs died of mycloproliferative syndrome (MPS), while one of four 4 μCi/day and one of four 12 μCi/day dogs died from MPS. In addition, another 12 μCi/day dog died of osteosarcoma and two others in the same group showed skeletal changes related to 90 Sr exposure. Other deaths were as could be expected in normal canine populations. Lifetime skeletal doses, determined by periodic whole-body counting, were 1990-3750, 1880-9230, and 6360-14,680 rad for the 1.3, 4, and 12 μCi/day groups, respectively. Comparison of these values with those from the large 90 Sr toxicity study at Davis in which 90 Sr feeding ended at 18 months of age indicates similar average skeletal doses from the two types of feeding regimens. The similarity of the skeletal doses may relate to the inability of 90 Sr to be incorporated to any great extent into a mature skeleton that no longer has the high calcium turnover associated with early life. As a result, deaths from lifetime 90 Sr ingestion appeared no earlier than when 90 Sr ingestion ended in early adulthood

  19. Robust half-metallicity of hexagonal SrNiO_3

    International Nuclear Information System (INIS)

    Chen, Gao-Yuan; Ma, Chun-Lan; Chen, Da; Zhu, Yan

    2016-01-01

    In the rich panorama of the electronic and magnetic properties of 3d transition metal oxides SrMO_3 (M=Ti, V, Cr, Mn, Fe, Co, Ni, Cu), one member (SrNiO_3) is missing. In this paper we use GGA+U method based on density functional theory to examine its properties. It is found that SrNiO_3 is a ferromagnetic half-metal. The charge density map shows a high degree of ionic bonding between Sr and other atoms. Meanwhile, a covalent-bonding Ni–O–Ni–O–Ni chain is observed. The spin density contour of SrNiO_3 further indicates that the magnetic interaction between Ni atoms mediated by O is semicovalent exchange. The density of states are examined to explore the unusual indirect magnetic-exchange mechanism. Corresponding to the total energies results, a robust half-metallic character is observed, suggesting a promising giant magneto-optical Kerr property of the material. The partial density of states are further examined to explore the origin of ferromagnetic half-metallicity. The O atoms are observed to have larger contribution at fermi level than Ni atoms to the spin-polarized states, demonstrating that O atoms play a critical role in ferromagnetic half-metallicity of SrNiO_3. Hydrostatic pressure effect is examined to evaluate how robust the half-metallic ferromagnetism is. - Graphical abstract: (a) The total energy as a function of the lattice constant a for hexagonal SrNiO3 with various magnetic phases. (b) The total electronic density of states for hexagonal SrNiO_3 with FM configuration from GGA+U calculations. (c) Total electron-density distribution in the (110) plane. The colors gradually change from cyan (through pink) to yellow corresponding to charge density value from 0 to 4.0. (d) The magnetization density map in the (110) plane. The colors range from blue (through green) to red corresponding to magnetization density value from −0.15 to 0.45. Black and white contours stand for positive and negative values, respectively. - Highlights: • Hexagonal Sr

  20. The implicit effect of texturizing field on the elastic properties of magnetic elastomers revealed by SANS

    Energy Technology Data Exchange (ETDEWEB)

    Balasoiu, M., E-mail: balas@jinr.ru [Joint Institute of Nuclear Research, Dubna (Russian Federation); Horia Hulubei National Institute for Physics and Nuclear Engineering, Bucharest (Romania); Lebedev, V.T. [St.Petersburg Nuclear Physics Institute NRC KI, Gatchina (Russian Federation); Raikher, Yu.L. [Institute of Continuous Media Mechanics, Russian Academy of Sciences, Ural Branch, Perm (Russian Federation); Bica, I.; Bunoiu, M. [West University of Timisoara, Department of Physics (Romania)

    2017-06-01

    Small angle neutron scattering method (SANS) is used to characterize the structure properties of the polymer matrix of magnetic elastomers (MEs) of the same material content but with different magnetic textures. For that, series of silicone-rubber elastomers mixed with a ferrofluid and polymerized with/without external magnetic field were studied. In the species of pure rubber and the ME samples synthesized without field, SANS reveals a substantial number of large polymer coils (blobs) which are vertically prolate. The case of MEs polymerized under the magnetic field that is also vertically directed, is different. SANS data indicates that there the blobs are preferably elongated in the direction normal to the field. - Highlights: • SANS method is used to determine the structure of SR elastomers polymerized with ferrofluid in/no external magnetic field. • In the rubber and ME samples synthesized without field, SANS reveals a substantial number of vertically prolate blobs. • For MEs polymerized in vertical magnetic field, results that the blobs are elongated in the direction normal to the field. • Isotropic and texturized MEs differ by the filler structure and by intrinsic elastic properties of the matrix as well.

  1. Colour relations for Mira and Semiregular (SR) type stars

    International Nuclear Information System (INIS)

    Guney, Yavuz; Yesilyaprak, Cahit

    2016-01-01

    In this study, the period-colour relations, the colour-colour relations and the effective temperature were examined for Semiregular (SR) and Mira type variable stars. SR variables show an obvious period-colour relations, especially in infrared (IR). There are differences between SR and Mira type variable stars with respect to their colour relations. It has been thought that these differencies are caused by their mass loss rates and their effective temperatures. (paper)

  2. The dynamics of central Main Ethiopian Rift waters: Evidence from {delta}D, {delta}{sup 18}O and {sup 87}Sr/{sup 86}Sr ratios

    Energy Technology Data Exchange (ETDEWEB)

    Rango, Tewodros, E-mail: tewodros.godebo@duke.edu [Division of Earth and Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States)] [Addis Ababa University, Department of Earth Sciences, P.O. Box 1176, Addis Ababa (Ethiopia); Petrini, Riccardo; Stenni, Barbara [University of Trieste, Department of Geosciences, Via Weiss 1, I-34100 Trieste (Italy); Bianchini, Gianluca [Istituto di Geoscienze e Georisorse-CNR, Pisa (Italy)] [Department of Earth Sciences, University of Ferrara, Via Saragat 1, 44100 Ferrara (Italy); Slejko, Francesca [University of Trieste, Department of Geosciences, Via Weiss 1, I-34100 Trieste (Italy); Beccaluva, Luigi [Department of Earth Sciences, University of Ferrara, Via Saragat 1, 44100 Ferrara (Italy); Ayenew, Tenalem [Addis Ababa University, Department of Earth Sciences, P.O. Box 1176, Addis Ababa (Ethiopia)

    2010-12-15

    Research highlights: {yields} Chemical and isotope ({delta}D, {delta}{sup 18}O and {sup 87}Sr/{sup 86}Sr) techniques are applied to understand various hydrological processes in the Main Ethiopian Rift. {yields} Some of the studied groundwaters display a depleted {delta}D-{delta}{sup 18}O composition when compared to the present-day average precipitation, thus suggesting that the rift floor aquifers also contains paleo-meteoric waters recharge associated with deep flow system. {yields} The pristine waters coming from the highlands display isotopic compositions characterized by less radiogenic {sup 87}Sr/{sup 86}Sr (and more depleted {delta}D, {delta}{sup 18}O). This isotopic signature subsequently evolves towards higher {sup 87}Sr/{sup 86}Sr by an interaction with the more radiogenic rhyolites of the rift and their weathered and redeposited products. - Abstract: Water samples from cold and geothermal boreholes, hot springs, lakes and rivers were analyzed for {delta}D, {delta}{sup 18}O and {sup 87}Sr/{sup 86}Sr compositions in order to investigate lake water-groundwater mixing processes, water-rock interactions, and to evaluate groundwater flow paths in the central Main Ethiopian Rift (MER) of the Ziway-Shala basin. Different ranges of isotopic values were recorded for different water types: hot springs show {delta}{sup 18}O -3.36 to +3.69 and {delta}D -15.85 to +24.23, deep Aluto-Langano geothermal wells show {delta}{sup 18}O -4.65 to -1.24 and {delta}D -12.39 to -9.31, groundwater wells show {delta}{sup 18}O -3.99 to +5.14 and {delta}D -19.69 to +32.27, whereas the lakes show {delta}{sup 18}O and {delta}D in the range +3.98 to +7.92 and +26.19 to +45.71, respectively. The intersection of the Local Meteoric Water Line (LMWL: {delta}D = 7 {delta}{sup 18}O + 11.2, R{sup 2} = 0.94, n = 42) and the Local Evaporation Line (LEL: {delta}D = 5.63{delta}{sup 18}O + 8, n = 14, R{sup 2} = 0.82) was used to estimate the average isotopic composition of recharge water into the

  3. The role of Sr2+ on the structure and reactivity of SrO-CaO-ZnO-SiO2 ionomer glasses.

    Science.gov (United States)

    Boyd, Daniel; Towler, Mark R; Watts, Sally; Hill, Robert G; Wren, Anthony W; Clarkin, Owen M

    2008-02-01

    The suitability of Glass Polyalkenoate Cements (GPCs) for use in orthopaedics is retarded by the presence in the glass phase of aluminium, a neurotoxin. Unfortunately, the aluminium ion plays an integral role in the setting process of GPCs and its absence is likely to hinder cement formation. However, the authors have previously shown that aluminium free GPCs may be formulated based on calcium zinc silicate glasses and these novel materials exhibit significant potential as hard tissue biomaterials. To further improve their potential, and given that Strontium (Sr) based drugs have had success in the treatment of osteoporosis, the authors have substituted Calcium (Ca) with Sr in the glass phase of a series of aluminium free GPCs. However to date little data exists on the effect SrO has on the structure and reactivity of SrO-CaO-ZnO-SiO(2) glasses. The objective of this work was to characterise the effect of the Ca/Sr substitution on the structure of such glasses, and evaluate the subsequent reactivity of these glasses with an aqueous solution of Polyacrylic acid (PAA). To this end (29)Si MAS-NMR, differential scanning calorimetry (DSC), X-ray diffraction, and network connectivity calculations, were used to characterize the structure of four strontium calcium zinc silicate glasses. Following glass characterization, GPCs were produced from each glass using a 40 wt% solution of PAA (powder:liquid = 2:1.5). The working times and setting times of the GPCs were recorded as per International standard ISO9917. The results acquired as part of this research indicate that the substitution of Ca for Sr in the glasses examined did not appear to significantly affect the structure of the glasses investigated. However it was noted that increasing the amount of Ca substituted for Sr did result in a concomitant increase in setting times, a feature that may be attributable to the higher basicity of SrO over CaO.

  4. Potential of Sr isotopic analysis in ceramic provenance studies: Characterisation of Chinese stonewares

    Energy Technology Data Exchange (ETDEWEB)

    Li Baoping [Advanced Centre for Queensland University Isotope Research Excellence (ACQUIRE), University of Queensland, Brisbane, Qld 4072 (Australia)]. E-mail: b.li@uq.edu.au; Zhao Jianxin [Advanced Centre for Queensland University Isotope Research Excellence (ACQUIRE), University of Queensland, Brisbane, Qld 4072 (Australia); Greig, Alan [Advanced Centre for Queensland University Isotope Research Excellence (ACQUIRE), University of Queensland, Brisbane, Qld 4072 (Australia); Collerson, Kenneth D. [Advanced Centre for Queensland University Isotope Research Excellence (ACQUIRE), University of Queensland, Brisbane, Qld 4072 (Australia); Zhuo Zhenxi [Shaanxi Provincial Institute of Archaeology, Xi' an 710054 (China); Feng Yuexin [Advanced Centre for Queensland University Isotope Research Excellence (ACQUIRE), University of Queensland, Brisbane, Qld 4072 (Australia)

    2005-11-15

    We compare the trace element and Sr isotopic compositions of stoneware bodies made in Yaozhou and Jizhou to characterise these Chinese archaeological ceramics and examine the potential of Sr isotopes in provenance studies. Element concentrations determined by ICP-MS achieve distinct characterisation for Jizhou samples due to their restricted variation, yet had limited success with Yaozhou wares because of their large variability. In contrast, {sup 87}Sr/{sup 86}Sr ratios in Yaozhou samples have a very small variation and are all significantly lower than those of Jizhou samples, which show a large variation and cannot be well characterised with Sr isotopes. Geochemical interpretation reveals that {sup 87}Sr/{sup 86}Sr ratios will have greater potential to characterise ceramics made of low Rb/Sr materials such as kaolin clay, yet will show larger variations in ceramics made of high Rb/Sr materials such as porcelain stone.

  5. Optical properties of SrTiO3 films

    International Nuclear Information System (INIS)

    Agasiyev, A.A.; Magerramov, E.M.; Mammadov, M.Z.; Sarmasov, S.M.

    2010-01-01

    The spectrums of optical absorption of amorphous and single crystalline films SrTiO 3 at temperatures : 105 K, 300 K, 400 K are investigated. The temperature dependences of slope absorption edge, forbidden gap and characteristic constant of Urbah rule are obtained. The forbidden gap of single crystalline film SrTiO 3 and average shift shift of absorption edge degree are defined. It is established that edge of optical absorption of SrTiO 3 film is obeyed to Urbah rule and the absorption in the investigated region is caused by the transition of electron interacting with phonon

  6. Quasi-two-dimensional Fermi-liquid state in Sr2RhO4-δ

    International Nuclear Information System (INIS)

    Nagai, Ichiro; Shirakawa, Naoki; Umeyama, Norio; Ikeda, Shin-ichi

    2010-01-01

    Single crystals of layered perovskite Sr 2 RhO 4-δ (δ=0.0 and 0.1) are successfully grown by the floating-zone method. Stoichiometric single crystals (Sr 2 RhO 4.0 ) are obtained by O 2 -annealing the as-grown crystals (Sr 2 RhO 3.9 ). Sr 2 RhO 4.0 and Sr 2 RhO 3.9 show quasi-two-dimensional Fermi-liquid behavior at low temperatures, whereas there are large differences in the anisotropy of electrical resistivity ρ c (3 K)/ρ ab (3 K) and Wilson ratio R w between Sr 2 RhO 4.0 and Sr 2 RhO 3.9 : ρ c (3 K)/ρ ab (3 K)=2400 (19000) and R w =3.8 (6.4) for Sr 2 RhO 4.0 (Sr 2 RhO 3.9 ). The differences observed between the temperature dependence of the in-plane electrical resistivity (T 2 RhO 4.0 and Sr 2 RhO 3.9 are mainly derived from those between the density of states and band structure near the corresponding Fermi level. This indicates that the changes in these physical properties, which are accompanied by oxygen defects in the Sr 2 RhO 4-δ system, can be explained by the rigid band model. Moreover, these results suggest that t 2g band-filling can be controlled by adjusting the oxygen defect content δ in the Sr 2 RhO 4-δ system. Although many similarities are observed in this study between the physical properties of Sr 2 RhO 4.0 and Sr 2 RuO 4 . Sr 2 RhO 4.0 does not exhibit superconductivity down to 36 mK. (author)

  7. The ternary post-transition metal carbodiimide SrZn(NCN){sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Corkett, Alex J.; Konze, Philipp M. [Institute of Inorganic Chemistry, RWTH Aachen University, Aachen (Germany); Dronskowski, Richard [Institute of Inorganic Chemistry, RWTH Aachen University, Aachen (Germany); Juelich-Aachen Research Alliance (JARA-HPC), RWTH-Aachen University, Aachen (Germany)

    2017-11-17

    SrZn(NCN){sub 2}, the first example of a ternary post-transition metal carbodiimide, was prepared by a solid-state metathesis reaction. The crystal structure was solved from PXRD data and found to adopt the orthorhombic (Cmcm) BaZnSO structure, a high symmetry modification of that expressed by the oxide analogue SrZnO{sub 2}. Locally, SrZn(NCN){sub 2} features ZnN{sub 4} tetrahedra and SrN{sub 6} trigonal prisms similar to those in quarternary LiSr{sub 2}M(NCN){sub 4} (M = Al{sup 3+} and Ga{sup 3+}) phases, however, the overall topologies are distinct with single chains in the former and double chains in the latter. Electronic structure calculations indicate an indirect bandgap of about 2.95 eV in SrZn(NCN){sub 2}, slightly lower than the experimentally observed bandgap of 3.4 eV in SrZnO{sub 2} and consistent with a greater degree of covalency. The structural similarities between SrZn(NCN){sub 2} and oxychalcogenide analogues highlight the pseudochalcogenide character of NCN{sup 2-} and suggest that the title compound may serve as a template for accessing novel ternary carbodiimides featuring tetrahedrally coordinated transition metals. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Subsolidus Phase Relations of the CoOx-CuO-SrO System  

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude

    2017-01-01

    The subsolidus phase relations of the CoOx-CuO-SrO system were investigated in air. The samples were equilibrated at 900 °C. The pseudo-ternary section contains three stoichiometric binary oxide phases (Sr2CuO3, SrCuO2 and Sr14Cu24O41−δ) and a binary oxide solid solution: Sr6+xCo5O15+δ (0 ≤ x ≤ 0.......36). Two binary phases extend into the ternary system forming solid solutions, i.e., Sr14Cu24−xCoxO41−δ (0 ≤ x ≤ 5) and Sr6+xCo5−yCuyO15+δ (0 ≤ x ≤ 0.36, 0 ≤ y ≤ 1.0). The Sr6+xCo5O15+δ solid solution was found to undergo a phase separation into a mixture of Sr6Co5O15−δ and Sr14Co11O33 upon annealing...

  9. Preparation of Sr7Mn4O13F2 by the topotactic reduction and subsequent fluorination of Sr7Mn4O15.

    Science.gov (United States)

    Saratovsky, Ian; Lockett, Michelle A; Rees, Nicholas H; Hayward, Michael A

    2008-06-16

    The topotactic reduction and subsequent fluorination of Sr7Mn4O15 yields a phase of composition Sr7Mn4O13F2. Characterization of this phase utilizing powder neutron diffraction and 19F NMR shows that the fluoride ions are located on a single anion site, the same crystallographic site that is vacant in the reduced intermediate Sr7Mn4O13.

  10. ) m /SrVO3 ( m = 5, 6) Superlattices

    KAUST Repository

    Dai, Qingqing; Lü ders, Ulrike; Fré sard, Raymond; Eckern, Ulrich; Schwingenschlö gl, Udo

    2018-01-01

    The (LaV3+O3)m/SrV4+O3 (m = 5, 6) superlattices are investigated by first principles calculations. While bulk LaVO3 is a C‐type antiferromagnetic semiconductor and bulk SrVO3 is a paramagnetic metal, semiconducting A‐type antiferromagnetic states

  11. Microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys.

    Science.gov (United States)

    Zhao, Chaoyong; Pan, Fusheng; Zhang, Lei; Pan, Hucheng; Song, Kai; Tang, Aitao

    2017-01-01

    In this study, as-extruded Mg-Sr alloys were studied for orthopedic application, and the microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys were investigated by optical microscopy, scanning electron microscopy with an energy dispersive X-ray spectroscopy, X-ray diffraction, tensile and compressive tests, immersion test, electrochemical test and cytotoxicity test. The results showed that as-extruded Mg-Sr alloys were composed of α-Mg and Mg 17 Sr 2 phases, and the content of Mg 17 Sr 2 phases increased with increasing Sr content. As-extruded Mg-Sr alloy with 0.5wt.% Sr was equiaxed grains, while the one with a higher Sr content was long elongated grains and the grain size of the long elongated grains decreased with increasing Sr content. Tensile and compressive tests showed an increase of both tensile and compressive strength and a decrease of elongation with increasing Sr content. Immersion and electrochemical tests showed that as-extruded Mg-0.5Sr alloy exhibited the best anti-corrosion property, and the anti-corrosion property of as-extruded Mg-Sr alloys deteriorated with increasing Sr content, which was greatly associated with galvanic couple effect. The cytotoxicity test revealed that as-extruded Mg-0.5Sr alloy did not induce toxicity to cells. These results indicated that as-extruded Mg-0.5Sr alloy with suitable mechanical properties, corrosion resistance and good cytocompatibility was potential as a biodegradable implant for orthopedic application. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. mu SR in Organic and Free Radical Chemistry

    CERN Multimedia

    2002-01-01

    Experiment SC82 was begun as a simple attempt to substitute positive muons into polymer molecules, and thereby to use the @mSR technique to study the mechanical relaxation of the different molecular groups. \\\\ \\\\ The experiment has since developed in several directions and has produced a wealth of information on the properties of muonic molecules, and adequately demonstrated the potential of @mSR as applied to molecular physics and chemistry. Physics aspects are now covered by a new experiment code SC95.\\\\ \\\\ The present experiment includes studies where the position occupied by the muon in the molecule (or crystal lattice) is readily established and the @mSR signal is exploited to reveal the intrinsic properties of the material. In this respect the @mSR techniques may be regarded simply as an experimental tool to probe the molecular behaviour of a chemical system. \\\\ \\\\ Two main classes of application include the measurement of isotope effects, where differences between muonic and corresponding photonic radi...

  13. Study on absorption, accumulation and distribution of 90Sr in yellow-feather broiler

    International Nuclear Information System (INIS)

    Shang Zhaorong; Xu Shiming; Zhao Wenhu; Hou Lanxin

    1993-04-01

    The feeding experiment was carried out for yellow-feather broiler with 90 Sr(NO 3 ) 2 having activities of 1.85 x 10 0 ∼ 1.85 x 10 4 Bq/chicken to observe the regular pattern of absorption and distribution of 90 Sr in its organs and tissues. The results are as follows: The absorption rate of 90 Sr by oral feeding is very low. The most of 90 Sr is drained away by daily excreta from the body. The half-time of its feeding is within 24 hours. The accumulated dose varies with the time and different feeding methods. The more 90 Sr is fed, the more 90 Sr is absorbed, however, the uptake rate of 90 Sr is decreasing. The distribution of 90 Sr for bone is very strong and the partition ratio is about 90%. The absorption coefficient of 90 Sr in organs and tissues of broiler is presented

  14. PSA de radio Mes de Concientización sobre las ETS PSA de radio (30 seg) (STD Awareness Month PSA (:30))

    Centers for Disease Control (CDC) Podcasts

    2011-04-19

    Abril es el Mes Nacional de Concientización sobre las Enfermedades de Transmisión Sexual (ETS). Las ETS pueden afectar a cualquier persona. Muchas ETS no tienen síntomas, por lo que es importante hacerse pruebas de detección.  Created: 4/19/2011 by National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention.   Date Released: 4/20/2011.

  15. Radionuclide transport report for the safety assessment SR-Site

    Energy Technology Data Exchange (ETDEWEB)

    2010-12-15

    This document compiles radionuclide transport calculations of a KBS-3 repository for the safety assessment SR-Site. The SR-Site assessment supports the licence application for a final repository at Forsmark, Sweden

  16. Uncertainty and Detection Limit in Determination of 89,90Sr by Cherenkov Counting

    International Nuclear Information System (INIS)

    Grahek, Z.; Karanovic, G.; Nodilo, M.

    2013-01-01

    The methodology for the rapid determination of 89,90Sr in normal and emergency situations is given. Methodology is based on simultaneous separation of strontium and yttrium from samples and quantitative 89,90Sr determination by Cherenkov counting within three days. Methodology for quantitative determination by Cherenkov counting based on following changes of sample activity during the time is described and discussed. It has been shown that 89,90Sr can be determined with acceptable accuracy when 89Sr/90Sr ratio is over 10:1. Obtained results show that by using low level liquid scintillation counter it can be possible to determine 89Sr and 90Sr in broad range of concentration activities (1 - 1000 Bq (kgL) -1 ) with uncertainties below 10% within 2-3 days. Results also show that accuracy of determination of 89Sr (and 90Sr) depends on determination of difference between separation and counting time when activity ratio of 89Sr/90Sr is high. Analysis of combined uncertainty shows that it mainly depends on uncertainty of efficiency and recovery determination, uncertainty of activities determination for both isotopes and level of background radiation. Portion of each in combined uncertainty depend on level of activity of each isotope and its activity ratio.(author)

  17. High Sr/Y rocks are not all adakites!

    Science.gov (United States)

    Moyen, Jean-François

    2010-05-01

    The name of "adakite" is used to describe a far too large group of rocks, whose sole common feature is high Sr/Y and La/Yb ratios. Defining adakites only by this criterion is misleading, as the definition of this group of rocks does include many other criteria, including major elements. In itself, high (or commonly moderate!) Sr/Y ratios can be achieved via different processes: melting of a high Sr/Y (and La/Yb) source; deep melting, with abundant residual garnet; fractional crystallization or AFC; or interactions of felsic melts with the mantle, causing selective enrichment in LREE and Sr over HREE. A database of the compositions of "adakitic" rocks - including "high silica" and "low silica" adakites, "continental" adakites and Archaean adakites—was assembled. Geochemical modeling of the potential processes is used to interpret it, and reveals that (1) the genesis of high-silica adakites requires high pressure evolution (be it by melting or fractionation), in equilibrium with large amounts of garnet; (2) low-silica adakites are explained by garnet-present melting of an adakite-metasomatized mantle, i.e at depths greater than 2.5 GPa; (3) "Continental" adakites is a term encompassing a huge range of rocks, with a corresponding diversity of petrogenetic processes, and most of them are different from both low- and high- silica adakites; in fact in many cases it is a complete misnomer and the rocks studied are high-K calc-alkaline granitoids or even S-type granites; (4) Archaean adakites show a bimodal composition range, with some very high Sr/Y examples (similar to part of the TTG suite) reflecting deep melting (> 2.0 GPa) of a basaltic source with a relatively high Sr/Y, while lower Sr/Y rocks formed by shallower (1.0 GPa) melting of similar sources. Comparison with the Archaean TTG suite highlights the heterogeneity of the TTGs, whose composition spreads the whole combined range of HSA and Archaean adakites, pointing to a diversity of sources and processes

  18. Determination of Sr-90 in environmental samples using solid phase extraction disk

    International Nuclear Information System (INIS)

    Zal U'yun Wan Mahmood

    2002-01-01

    A method is described for determination of Sr-90 in environmental samples using solid phase extraction disk (Empore TM Strontium Rad Disk) and GM counter. To determine the optimum condition for capacity of Empore TM Strontium Rad Disk, its characterization studies such as the effects Sr content, acidity (molarity) of acids, presence of Ca 2+ and other major ions (Na + , Mg 2+ etc), influence of interference (Pb and Bi) and others were carried out. An optimized the using of Empore TM Strontium Rad Disk for determination of Sr-90 was validated by application to environmental samples. Quantitative recoveries above 95%for Sr (stable) were recorded in 6M HCl condition. Typical environmental samples may contain an assortment of anionic and cationic species, but in general, Empore TM Strontium Rad Disk has enough capacity to effectively separate Sr for wide variety of aqueous solutions. Sr recovery in a matrix-free or the content of matrix less than 300 mg/sample is typically greater than 99% is reported in this research work. In particular, sample, which may contain interference such as Pb and Bi would require an addition separation step before processing to ensure an accurate measurement of Sr. In this research work, radiotracer 85 Sr was used to monitor the behavior of Sr and calculation its recovery. For analytical methods that can count Y-90, the Sr-90 activity/concentration in environmental sample was calculated. The concentration of Sr-90 in ash sample (Quality Controled Sample) of 276 ± 18 Bq/kg ash was determined from Y-90 activity. The relative percent difference of 1.1% was achievable for Empore TM Sr-Rad Disk methods when compared to the conventional method (fumed-HNO 3 method) - 279 ± 11 Bq/kg ash. (Author)

  19. The dynamics of accumulation and disappearance of {sup 89}Sr in tea

    Energy Technology Data Exchange (ETDEWEB)

    Chuanqun, Chen; Shouxiang, Wang; Yongxi, Zhang; Zhiming, Sun [Zhejiang Agricultural Univ., Hangzhou (China). Inst. of Nuclear Agricultural Sciences

    1994-06-01

    The {sup 89}Sr was put into a tea tree-soil system by different ways. The results showed that for {sup 89}Sr put into the system through the above-ground 1 part of tea tree, its concentration in tea was much higher than that through soil. The concentration of {sup 89}Sr in older tea was higher than that in shoot for the same treatment. The accumulation and disappearance of {sup 89}Sr in tea varied with the treatments. For the treatment through the above-ground part, the concentrations of {sup 89}Sr in older tea and shoot were monotonously decreasing with time. For the treatment through soil the concentration of {sup 89}Sr in shoot increased initially to a maximum value, then decreased slowly; while the concentration of {sup 89}Sr in older tea increased quickly in a definite period, then increased slowly to gain a saturated value. In addition, the values of concentration factor of {sup 89}Sr in the older tea and shoot were determined, too.

  20. Determination methods of the 90Sr in a sample of contaminated water

    International Nuclear Information System (INIS)

    Ometakova, J.; Silvia Dulanska, S.

    2009-01-01

    The aim of this work was a comparison of selected products from the point of view of the amount of strontium yields, time needed and possibility of multiple use of sorbents. Three commercial products: 3M Empore Stroncium Rad Disk, AnaLig , Sr-Resin and two classical methods: liquid-liquid extraction with tributylphosphate and carbonate coprecipitation (to eliminate interferents) were used for separation of 90 Sr. The model sample was used in radiochemical analysis to check multiple use of 3M Em-pore Stroncium Rad Disk a AnaLig. A radiochemical strontium yield was traced by using radionuclide 85 Sr. The model sample was also used to optimize conditions of strontium separation. The results were used for 90 Sr determination from a sample of permeating groundwater from a supervised zone of a Nuclear Power Plant Jaslovske Bohunice. We have found out that 90 Sr separation with sorbents AnaLig Sr-01, 3M Empore Sr Rad Disk is as effective as with sorbent Sr-Resin in matrices of contaminated water. (authors)

  1. Effect of Flowing Water on Sr Sorption Changes of Hydrous Sodium Titanate

    OpenAIRE

    Youko Takahatake; Atsuhiro Shibata; Kazunori Nomura; Tsutomu Sato

    2017-01-01

    Radioactive contaminated water has been generated at the Fukushima Daiichi Nuclear Power station (F1NPS). Hydrous sodium titanate (SrTreat®) is able to remove radioactive Strontium (Sr) from this water. Knowing the amount of radioactive nuclides in the used as-received SrTreat® is important for effective disposal and deposition of the F1NPS waste. This study investigated changes in the ability of SrTreat® to sorb Sr, and to understand the causes of changes in the sorbing. An investigation of ...

  2. Toxicity of inhaled 90SrCl2 in beagle dogs. XI

    International Nuclear Information System (INIS)

    Muggenburg, B.A.; Rebar, A.H.; Benjamin, S.A.; Boecker, B.B.; Jones, R. K.; McClellan, R.O.; Pickrell, J.A.

    1977-01-01

    Studies on the metabolism, dosimetry, and effects of inhaled 90 SrCl 2 in the Beagle dog are continuing in an effort to provide a basis for assessing the consequences of inhaling 90 Sr such as might be released in certain nuclear accidents. Seventy-two dogs were exposed to aerosols containing 90 Sr resulting in initial body burdens ranging from 2.5 to 250 μCi 90 Sr/kg body weight. Forty-eight of these dogs are being maintained for lifetime observation. Twenty-five unexposed dogs serve as controls. The long-term retained burden (LTRB) in these dogs ranged from 1 to 120 μCi 90 Sr/kg. Twenty-four dogs with a mean LTRB of 38 μCi 90 Sr/kg have been assigned to a sacrifice study. Two of these dogs and one control dog were sacrificed at five days, one month and one year after inhalation of 90 Sr. To date, 51 90 Sr-exposed dogs have died or have been euthanized, six during the first 31 days after inhalation of 90 Sr with bone marrow aplasia and 45 between 585 and 4236 days after inhalation of 90 Sr. The latter group includes 12 dogs with bone-related hemangiosarcomas, 16 with osteosarcomas, three with fibrosarcomas, three with osteochondrosarcomas, one with osteochondrofibrosarcoma, two with leukemia, one with a baso-squamous carcinoma of the skull, one with a squamous cell carcinoma of the maxilla, one with a squamous cell carcinoma of the frontal sinus, one with a hemangiosarcoma of the heart, one with a myxosarcoma of the skull, one with transitional cell carcinoma, one with bronchioalveolar carcinoma, one with an epileptic seizure, one with pneumonia, one with cerebellar hemorrhage and three with a malabsorption syndrome

  3. Thermodynamic assessment of the Sn–Sr system supported by first-principles calculations

    International Nuclear Information System (INIS)

    Zhao, Jingrui; Du, Yong; Zhang, Lijun; Wang, Aijun; Zhou, Liangcai; Zhao, Dongdong; Liang, Jianlie

    2012-01-01

    Highlights: ► All the literature data of Sn–Sr system is critically reviewed. ► First-principles calculation of enthalpy of formation is carried out for each compound. ► Thermodynamic parameters for Sn–Sr system are obtained by CALPHAD method. ► A hybrid approach of CALPHAD and first-principles calculations is recommended. - Abstract: A hybrid approach of CALPHAD and first-principles calculations was employed to perform a thermodynamic modeling of the Sn–Sr system. The experimental phase diagram and thermodynamic data available in the literature were critically reviewed. The enthalpies of formation for the 6 stoichiometric compounds (i.e. Sr 2 Sn, Sr 5 Sn 3 , SrSn, Sr 3 Sn 5 , SrSn 3 and SrSn 4 ) at 0 K were computed by means of first-principles calculations. These data were used as the experimental values in the optimization module PARROT in the subsequent CALPHAD assessment to provide thermodynamic parameters with sound physical meaning. A set of self-consistent thermodynamic parameters was finally obtained by considering reliable literature data and the first-principles computed results. Comprehensive comparisons between the calculated and measured quantities indicate that all the reliable experimental information can be satisfactorily accounted for by the present thermodynamic description.

  4. An EPR investigation of the dynamic Jahn-Teller effect in SrCl2:y(2 plus) and SrCl2:Sc(2 plus)

    Science.gov (United States)

    Herrington, J. R.; Estle, T. L.; Boatner, L. A.

    1972-01-01

    EPR spectra have been observed for SrCl2:Y(2+) and SrCl2:Sc(2+) at liquid helium temperatures. At 1.2 K the spectra were dominated by anisotropic hyperfine patterns whose lineshapes and angular dependences were explained using second order solutions of the effective Hamiltonian for an isolated 2Eg state split by large random internal strains. Pronounced asymmetries in some of the strin produced lineshapes for Srcl2:Sc(2+) are shown to result from second order terms in the solution of the effective Hamiltonian. Coexisting with the anisotropic hyperfine patterns are weak nearly isotropic hyperfine patterns with typical lineshapes. Variations in the apparent intensity of lines in these weak hyperfine patterns as functions of the applied magnetic field direction and temperature imply that these lines result from averaging by vibronic relaxation of a portion of the anisotropic pattern. The effective Hamiltonian parameters for SrCl2:La(2+), SrCl2:y(2+), and SrCl2:SC(2+) are analyzed in terms of crystal field theory modified to include a dynamic Jahn-Teller effect.

  5. Binding of Sr from milk by solid phase extraction with cryptand C222 sorbed on silica gel, cation exchange, chelating or adsorbent resins for simplified 90Sr analysis

    International Nuclear Information System (INIS)

    Tait, David; Wiechen, Arnold; Haase, Gerhard

    1995-01-01

    Several commercially available resins have been found to bind the bicyclic polyether cryptand C222 from aqueous acetonitrile solutions. The presence of C222 on some of these resins strongly improved their affinity for Sr, so that relatively small amounts of such resins sorbed Sr from milk. The resins investigated were silica gel, polyacrylic acid crosslinked with divinylbenzene (DVB), polystyrene crosslinked with divinylbenzene (PS-DVB) and PS-DVB containing sulphonate, aminomethylphosphonate, iminodiacetate and mercapto groups. The resins for which binding of C222 resulted in the largest improvement in Sr sorption from milk were PS-DVB containing mercapto groups (Chelite S) and silica gel (Si 60). Thus, 2 ml wet volume of either Chelite S containing 133 μmol of C222, or silica gel Si-60 containing 143 μmol of C222 sorbed 90 and 48%, respectively, of the Sr from 100-ml milk samples. As the sorption of Sr from milk by these systems is relatively slow, contact times of 24-36 h are required to attain these results. The Chelite S-C222 system separates Sr effectively from Cs and Ca. Under the conditions described here some 6% of the natural 40 K in milk sorbs with Sr to the resin. Ba behaves similarly to Sr. 90 Sr/ 90 Y sorbed on the silica gel Si-60-C222 system can be measured directly and efficiently by liquid scintillation counting. If adequate specificity can be attained this system might provide a very simple method of determining 90 Sr in milk

  6. Mid - infrared transmission of polycrystalline (LaSr) (MnNi)O3

    International Nuclear Information System (INIS)

    Laksanawati, W. D.; Kurniawan, B.; Saptari, S. A.

    2016-01-01

    Polycrystalline (LaSr)(MnNi)O 3 was shintesized using sol gel methods with nitrat precursors La(NO 3 ) 3 , Sr(NO 3 ) 2 , Mn(NO 3 ) 2 .4H 2 O, and Ni(NO3)2.6H2O and the different heating process. Sample (LaSr)(MnNi)O 3 with chemical formulation La 0,67 Sr 0,33 Mn 1-x Ni x O 3 with × = 0,05 and 0,10. We report the crystallite structure of La 0,67 Sr 0,33 Mn 1-x Ni x O 3 with x= 0,00 and 0,10 are single phase with characterization by X-ray diffraction. Refinement has result that crystallite size of La 0,67 Sr 0,33 Mn 0,95 Ni 0,05 O 3 is 24,67 and La 0,67 Sr 0,33 Mn 0,9 Ni 0,1 O 3 is 21,84 with crystallite system rombohedral, it show us that increasing at Ni composition influence of decreased crystallite size. Sampel (LaSr)(MnNi)O3 has been characterization with Fourier Transform Infrared with range of wave number from 450 to 4000 cm -1 were chategories at mid infrared wave. The FTIR pattern show to us that the Mn-O-Mn bounded has absorp infrared at wave number 605 cm -1 and the dominant peak at wave number 3750 cm -1 caused the hidroxy compound in sampel La 0,67 Sr 0,33 Mn 0,95 Ni 0,05 O 3 . (paper)

  7. Effect of methotrexate conjugated PAMAM dendrimers on the viability of MES-SA uterine cancer cells

    Directory of Open Access Journals (Sweden)

    Samreen Khatri

    2014-01-01

    Full Text Available The aim of this work was to synthesize methotrexate (MTX-polyamidoamine (PAMAM dendritic nanoconjugates and to study their effect on cell viability in uterine sarcoma cells. The amide-bonded PAMAM dendrimer-MTX conjugates were prepared by conjugation between the amine-terminated G5 dendrimer and the carboxylic groups of the MTX using a dicyclohexylcarbodiimide coupling reaction. The formation of conjugates was evaluated by ultraviolet (UV and 1 H nuclear magnetic resonance ( 1 H NMR spectroscopy studies. The cell survival of MES-SA cells, a uterine sarcoma cell line, was evaluated in the presence of the dendrimer-MTX nanoconjugate, using appropriate controls. The UV and 1 H NMR study confirmed the formation of covalent bonds between the drug and the dendrimer. The cell viability study indicated that the nanoconjugates had significantly improved cell killing compared to the free MTX.

  8. Toxicity of inhaled 90SrCl2 in Beagle dogs. XIII

    International Nuclear Information System (INIS)

    Muggenburg, B.A.; Hahn, F.F.; Boecker, B.B.; Jones, R.K.; McClellan, R.O.; Pickrell, J.A.

    1979-01-01

    The metabolism, dosimetry and biological effects of inhaled 90 SrCl 2 in the Beagle dog are being studied to provide a basis for assessing the consequences of inhaling 90 Sr such as might be released in certain nuclear accidents. Seventy-two dogs were exposed to aerosols containing 90 Sr resulting in initial body burdens ranging from 2.5 to 250 μCi 90 Sr/kg body weight. To date, 60 90 Sr-exposed dogs have died or have been euthanized, six during the first 31 days after inhalation of 90 Sr with bone marrow aplasia and 54 between 585 and 5109 days after inhalation of 90 Sr. The latter group includes 32 dogs with bone-related neoplasms, two with upper respiratory tract carcinomas and five dogs with various diseases of the lower respiratory tract and heart. The other 15 dogs and diseases in organs that received little or no radiation dose, such as the gastrointestinal tract, urinary tract and the central nervous system. The skeletons of the dogs dying with bone-related neoplasms received initial radiation dose rates of 3.2 to 55 rads/day and cumulative doses to death of 2800 to 22 000 rads. Fourteen control dogs have died or been euthanized, two during the last year with mammary carcinoma and intestinal lymphosarcoma. Serial observations are continuing on the six surviving 90 Sr dogs and six controls

  9. The new versatile general purpose surface-muon instrument (GPS) based on silicon photomultipliers for μSR measurements on a continuous-wave beam.

    Science.gov (United States)

    Amato, A; Luetkens, H; Sedlak, K; Stoykov, A; Scheuermann, R; Elender, M; Raselli, A; Graf, D

    2017-09-01

    We report on the design and commissioning of a new spectrometer for muon-spin relaxation/rotation studies installed at the Swiss Muon Source (SμS) of the Paul Scherrer Institute (PSI, Switzerland). This new instrument is essentially a new design and replaces the old general-purpose surface-muon (GPS) instrument that has been for long the workhorse of the μSR user facility at PSI. By making use of muon and positron detectors made of plastic scintillators read out by silicon photomultipliers, a time resolution of the complete instrument of about 160 ps (standard deviation) could be achieved. In addition, the absence of light guides, which are needed in traditionally built μSR instrument to deliver the scintillation light to photomultiplier tubes located outside magnetic fields applied, allowed us to design a compact instrument with a detector set covering an increased solid angle compared with the old GPS.

  10. Determination of Sr90 activity in human bones

    International Nuclear Information System (INIS)

    Mendonca, Anamelia Habib

    1970-01-01

    Several studies have been published in the literature on the extent and levels of radioactive contamination of food chains caused by fallout from nuclear weapon tests. According to UNSCEAR, these studies cover a great number of:-areas of the developed world, though large, areas of Asia, Africa and South-America are left aside with only, unsatisfactory information about the levels, of radioactive contamination. In 1968, UNSCEAR recommended that a survey on the contamination of biological materials such as human - bone by fission products and particularly Sr 90 should be encouraged on those areas where only fragmentary information was available. UNSCEAR recommendations call upon the fact that many individuals on such areas of the world have been exposed to Sr 90 contamination from birth to their adult area. Therefore, that group have an Sr 90 skeletal burden very much different from people exposed only at adult age. Based on these considerations, UNSCEAR recommendations called for Sr 90 analysis on human bones from different age groups. In Brazil, studies on the of Sr 90 in human bone are practically non-existent, except for the year of 1959. Following UNSCEAR recommendations, we decided to perform such a survey on Sr 90 levels in human bones. Samples were collected from individuals that died in Rio de Janeiro from accidents. These samples were firstly classified according to social level in very poor and poor groups. Samples were then classified in three age groups ranging 0-18, 18-30 and 30-40 years of age. Results show that levels found in the Brazilian age groups are close to the ones observed in Chile (1969), Argentina and Australia (1966-1968) and slightly, higher than -those observed in Venezuela, Senegal and Jamaica (1969). If one compares the results obtained for the North and South hemispheres respectively, one sees that there was a more pronounced decrease in the levels of Sr 90 content of the of some regions of South America. Our results show no

  11. Systèmes turbiditiques calcaires du Tithonien et du Barrémo-Bédoulien subalpins (SE de la France) (1-3 septembre 2005)

    OpenAIRE

    Ferry , Serge; Atrops , François; Backert , Nicolas; Lozano-Garcia , F.; Savary , Bérangère

    2005-01-01

    International audience; Les systèmes turbiditiques calcaires sont encore peu étudiés par rapport à leurs homologues silico-clastiques, bien que la notion de “calcaires allodapiques” soit à peu près aussi ancienne que la notion de turbidite. Une typologie des appareils calcaires (faciès, géométries, rapports avec les plates-formes carbonatées nourricières) reste à faire.

  12. Comparison of the Sr isotopic signatures in brines of the Canadian and Fennoscandian shields

    International Nuclear Information System (INIS)

    Negrel, Philippe; Casanova, Joel

    2005-01-01

    A synthesis of Sr isotope data from shallow and deep groundwaters, and brines from the Fennoscandian and Canadian Shields is presented. A salinity gradient is evident in the water with concentrations varying from approximately 1-75 g L -1 below 1500 m depth in the Fennoscandian Shield and from 10 up to 300 g L -1 below 650 m depth in the Canadian Shield. Strontium isotope ratios were measured to assess the origin of the salinity and evaluate the degree of water-rock interaction in the systems. In both shields, the Sr concentrations are enriched relative to Cl, defining a positive trend parallel to the seawater dilution line and indicative of Sr addition through weathering processes. The depth distribution for Sr concentration increases strongly with increasing depth in both shields although the variation in Sr-isotope composition does not mirror that of Sr concentrations. Strontium-isotope compositions are presented for surface waters, and groundwaters in several sites in the Fennoscandian and Canadian Shields. Numerous mixing lines can be drawn reflecting water-rock interaction. A series of calculated lines links the surface end-members (surface water and shallow groundwater) and the deep brines; these mixing lines define a range of 87 Sr/ 86 Sr ratios for the deep brines in different selected sites. All sites show a specific 87 Sr/ 86 Sr signature and the occurrence of large 87 Sr/ 86 Sr variations is site specific in both shields. In Canadian Shield brines, the Sr isotope ratios clearly highlight large water rock interaction that increases the 87 Sr/ 86 Sr ratio from water that could have been of marine origin. In contrast to the Canadian Shield, groundwater does not occur in closed pockets in the Fennoscandian, and the well-constrained 87 Sr/ 86 Sr signatures in deep brines should correspond to a large, well-mixed and homogeneous water reservoir, whose Sr isotope signature results from water-rock interaction

  13. 87Sr/86Sr Concentrations in the Appalachian Basin: A Review

    Energy Technology Data Exchange (ETDEWEB)

    Mordensky, Stanley P. [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States); National Energy Technology Lab. (NETL), Albany, OR (United States); Lieuallen, A. Erin [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States); National Energy Technology Lab. (NETL), Albany, OR (United States); Verba, Circe [National Energy Technology Lab. (NETL), Albany, OR (United States); Hakala, Alexandra [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States)

    2016-06-16

    This document reviews 87Sr/86Sr isotope data across the Appalachian Basin from existing literature to show spatial and temporal variation. Isotope geochemistry presents a means of understanding the geochemical effects hydraulic fracturing may have on shallow ground substrates. Isotope fractionation is a naturally occurring phenomenon brought about by physical, chemical, and biological processes that partition isotopes between substances; therefore, stable isotope geochemistry allows geoscientists to understand several processes that shape the natural world. Strontium isotopes can be used as a tool to answer an array of geological and environmental inquiries. In some cases, strontium isotopes are sensitive to the introduction of a non-native fluid into a system. This ability allows strontium isotopes to serve as tracers in certain systems. Recently, it has been demonstrated that strontium isotopes can serve as a monitoring tool for groundwater and surface water systems that may be affected by hydraulic fracturing fluids (Chapman et al., 2013; Kolesar Kohl et al., 2014). These studies demonstrated that 87Sr/86Sr values have the potential to monitor subsurface fluid migration in regions where extraction of Marcellus Shale gas is occurring. This document reviews publicly available strontium isotope data from 39 sample locations in the Appalachian Basin (Hamel et al., 2010; Chapman et al., 2012; Osborn et al., 2012; Chapman et al., 2013; Capo et al., 2014; Kolesar Kohl et al., 2014). The data is divided into two sets: stratigraphic (Upper Devonian/Lower Mississippi, Middle Devonian, and Silurian) and groundwater. ArcMap™ (ESRI, Inc.) was used to complete inverse distance weighting (IDW) analyses for each dataset to create interpolated surfaces in an attempt to find regional trends or variations in strontium isotopic values across the Appalachian Basin. 87Sr/86Sr varies up to ~ 0.011 across the

  14. Solid phase extraction for determination of 90Sr in water sample

    International Nuclear Information System (INIS)

    Ometakova, J.

    2009-01-01

    We studied the use of an extraction chromatography for determination of 90 Sr in samples of contaminated water. The aim of the thesis was to compare selected products from the point of view of the strontium yields and time needed. Three commercial products: 3M Empore Strontium Rad Disk, AnaLig, Sr-Resin and two classical methods: liquid-liquid extraction with tributylphosphate and carbonate co-precipitation (to eliminate interferers) were used for separation of 90 Sr. The water sample was used in radiochemical analysis for determination volume activity of 90 Sr. A radiochemical strontium yield was traced by using radionuclide 85 Sr. Samples were counted over a two week period to monitor the ingrowth of 90 Y on TRI CARB LSC counter. Samples were measured using an HPGe detector to find out 85 Sr recoveries at 514 keV line and they were counted directly by Cherenkov counting after the growth of 90 Y using TriCarb LSC counter after a two- week period (author)

  15. SR-B1 Is a Silica Receptor that Mediates Canonical Inflammasome Activation

    Directory of Open Access Journals (Sweden)

    Misato Tsugita

    2017-01-01

    Full Text Available The inhalation of silica dust is associated with fibrosis and lung cancer, which are triggered by macrophage inflammatory responses; however, how macrophages recognize silica remains largely unknown. Here, we identify by functional expression cloning the class B scavenger receptor SR-B1 as a silica receptor. Through an extracellular α-helix, both mouse and human SR-B1 specifically recognized amorphous and crystalline silica, but not titanium dioxide nanoparticles, latex nanoparticles, or monosodium urate crystals, although all particles exhibited negative surface potentials. Genetic deletion of SR-B1 and masking of SR-B1 by monoclonal antibodies showed that SR-B1-mediated recognition of silica is associated with caspase-1-mediated inflammatory responses in mouse macrophages and human peripheral blood monocytes. Furthermore, SR-B1 was involved in silica-induced pulmonary inflammation in mice. These results indicate that SR-B1 is a silica receptor associated with canonical inflammasome activation.

  16. Development of techniques for rapid analysis of 90Sr breakthrough and 90Y activity from a 90Sr-90Y generator

    International Nuclear Information System (INIS)

    Chism, S.E.; Goodwin, D.A.; Meares, C.F.

    1986-01-01

    Recently there has been interest in labelling monoclonal antibodies with therapeutic amounts of a pure beta emitting isotope. 90 Y offers many desirable features and may be conveniently and economically obtained from a 90 Sr- 90 Y generator. A potential hazard with this system is breakthrough of the parent 90 Sr which has a half life of 28 years and is an extremely toxic bone seeking isotope. Therefore it is essential that the daughter be completely separated from its parent. We have devised two simple techniques which allow us to monitor rapidly the amount of 90 Sr breakthrough and quantitate the 90 Y activity over a 5 log range. (author)

  17. Coexistence of spin frozen state and persistent spin dynamics in NaSrCo{sub 2}F{sub 7} as probed by μSR and NMR

    Energy Technology Data Exchange (ETDEWEB)

    Dengre, Shanu; Sarkar, Rajib; Braeuninger, Sascha Albert; Brueckner, Felix; Materne, Philipp; Klauss, Hans-Henning [Institute for Solid State Physics, TU Dresden (Germany); Krizan, Jason W.; Cava, Robert J. [Department of Chemistry, Princeton University, Princeton, NJ (United States); Luetkens, Hubertus; Baines, Chris [Laboratory for Muon-Spin Spectroscopy, Paul Scherrer Institute, Villigen (Switzerland)

    2016-07-01

    {sup 23}Na -and {sup 19}F NMR, and μSR experiments are performed to explore the microscopic properties of NaSrCo{sub 2}F{sub 7}, which is a newly discovered magnetically frustrated pyrochlore with weak bond disorder and with a frustration index of f = 42. While {sup 23}Na and {sup 19}F NMR experiments clearly suggest the presence of quasi static field distribution below ∝3 K as reflected in the huge NMR line broadening and wipe out effect of NMR signal intensity, μSR experiments on the other hand remains passive to this spin frozen state. Both NMR and μSR results indicate the slowing down of the magnetic (spin) fluctuations upon cooling towards the NMR spin frozen state. μSR relaxation rate increases slightly below ∝ 3 K, and remains not only constant down to 20 mK, but also stands independent in longitudinal magnetic field upto 4000 G implying that the spin fluctuations are dynamic. These observations suggest the coexistence of partial spin frozen state and persistent spin dynamics in NaSrCo{sub 2}F{sub 7}.

  18. Vadose Zone Infiltration Rates from Sr isotope Measurements

    Science.gov (United States)

    Maher, K.; Maher, K.; DePaolo, D. J.; DePaolo, D. J.; Conrad, M.

    2001-12-01

    Predicting infiltration rates and recharge through the vadose zone in arid regions is difficult and hence developing methods for the measurement of infiltration rates is important. We have been investigating the use of Sr isotope measurements for determining infiltration at the 200 Area plateau on the Hanford reservation in central Washington. In this context, infiltration affects the transport of contaminants to the water table as well as recharge of the groundwater system. Using Sr isotopes for this purpose requires drill core and water samples from the vadose zone, although leaches of the cores can substitute for water samples. Complementary information, including some constraints on regional recharge, can also be obtained using water samples from groundwater monitoring wells. The VZ method is based on the fact that the Sr isotope ratio of soil water just below the surface is often set by dissolution of aeolian material including carbonate, and this ratio is different from the average value in the deeper underlying vadose zone rock matrix. As water infiltrates, the Sr isotopic composition of the water changes toward the rock values as a result of Sr released from the rocks by weathering reactions. The rate of change with depth of the Sr isotope ratio of the vadose zone water is a function ultimately of q/R; the ratio of the infiltration flux (q) to the bulk rock weathering rate (R). Where it is possible to evaluate R, q can be estimated. As data accumulate it may be possible to improve the calibration of the method. At Hanford the vadose zone rock material is mostly unconsolidated sand, silt, and gravel of broadly granitic composition, which constitute the Hanford and Ringold formations. Annual precipitation is about 160 mm/yr. Drilling and coring of a ca. 70m hole to the water table in 1999 as part of the Hanford groundwater monitoring program, in a relatively undisturbed area of the site, allowed us to generate a unique Sr isotope data set. The Sr isotope

  19. Calcium-sensing receptor (CaSR): pharmacological properties and signaling pathways.

    Science.gov (United States)

    Conigrave, Arthur D; Ward, Donald T

    2013-06-01

    In this article we consider the mechanisms by which the calcium-sensing receptor (CaSR) induces its cellular responses via the control (activation or inhibition) of signaling pathways. We consider key features of CaSR-mediated signaling including its control of the heterotrimeric G-proteins Gq/11, Gi/o and G12/13 and the downstream consequences recognizing that very few CaSR-mediated cell phenomena have been fully described. We also consider the manner in which the CaSR contributes to the formation of specific signaling scaffolds via peptide recognition sequences in its intracellular C-terminal along with the origins of its high level of cooperativity, particularly for Ca(2+)o, and its remarkable resistance to desensitization. We also consider the nature of the mechanisms by which the CaSR controls oscillatory and sustained Ca(2+)i mobilizing responses and inhibits or elevates cyclic adenosine monophosphate (cAMP) levels dependent on the cellular and signaling context. Finally, we consider the diversity of the receptor's ligands, ligand binding sites and broader compartment-dependent physiological roles leading to the identification of pronounced ligand-biased signaling for agonists including Sr(2+) and modulators including l-amino acids and the clinically effective calcimimetic cinacalcet. We note the implications of these findings for the development of new designer drugs that might target the CaSR in pathophysiological contexts beyond those established for the treatment of disorders of calcium metabolism. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Strain Induced Magnetism in SrRuO3 Epitaxial Thin Films

    Energy Technology Data Exchange (ETDEWEB)

    Grutter, A.; Wong, F.; Arenholz, E.; Liberati, M.; Suzuki, Y.

    2010-01-10

    Epitaxial SrRuO{sub 3} thin films were grown on SrTiO{sub 3}, (LaAlO{sub 3}){sub 0.3}(SrAlO{sub 3}){sub 0.7} and LaAlO{sub 3} substrates inducing different biaxial compressive strains. Coherently strained SrRuO{sub 3} films exhibit enhanced magnetization compared to previously reported bulk and thin film values of 1.1-1.6 {micro}{sub B} per formula unit. A comparison of (001) and (110) SrRuO{sub 3} films on each substrate indicates that films on (110) oriented have consistently higher saturated moments than corresponding (001) films. These observations indicate the importance of lattice distortions in controlling the magnetic ground state in this transitional metal oxide.

  1. Resistance switching in epitaxial SrCoO{sub x} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk, E-mail: cu-jung@hufs.ac.kr [Department of Physics, Hankuk University of Foreign Studies, Yongin 449-791 (Korea, Republic of); Kim, Yeon Soo; Park, Bae Ho [Division of Quantum Phases and Devices, Department of Physics, Konkuk University, Seoul 143-791 (Korea, Republic of); Jeong, Huiseong; Park, Ji-Yong [Department of Physics and Division of Energy System Research, Ajou University, Suwon 443-749 (Korea, Republic of); Cho, Myung Rae; Park, Yun Daniel [Department of Physics and Astronomy and Center for Subwavelength Optics, Seoul National University, Seoul 151-747 (Korea, Republic of); Choi, Woo Seok [Department of Physics, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kim, Dong-Wook [Department of Physics, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Jin, Hyunwoo; Lee, Suyoun [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong [Department of Material Science and Engineering, Seoul National University, Seoul 151-747 (Korea, Republic of)

    2014-08-11

    We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO{sub 3} (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO{sub 2.5}) and conducting perovskite (SrCoO{sub 3−δ}) depending on the oxygen content. The current–voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoO{sub x} thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO{sub 2.5}.

  2. The F-BAR domains from srGAP1, srGAP2 and srGAP3 regulate membrane deformation differently

    Science.gov (United States)

    Coutinho-Budd, Jaeda; Ghukasyan, Vladimir; Zylka, Mark J.; Polleux, Franck

    2012-01-01

    Summary Coordination of membrane deformation and cytoskeletal dynamics lies at the heart of many biological processes critical for cell polarity, motility and morphogenesis. We have recently shown that Slit-Robo GTPase-activating protein 2 (srGAP2) regulates neuronal morphogenesis through the ability of its F-BAR domain to regulate membrane deformation and induce filopodia formation. Here, we demonstrate that the F-BAR domains of two closely related family members, srGAP1 and srGAP3 [designated F-BAR(1) and F-BAR(3), respectively] display significantly different membrane deformation properties in non-neuronal COS7 cells and in cortical neurons. F-BAR(3) induces filopodia in both cell types, though less potently than F-BAR(2), whereas F-BAR(1) prevents filopodia formation in cortical neurons and reduces plasma membrane dynamics. These three F-BAR domains can heterodimerize, and they act synergistically towards filopodia induction in COS7 cells. As measured by fluorescence recovery after photobleaching, F-BAR(2) displays faster molecular dynamics than F-BAR(3) and F-BAR(1) at the plasma membrane, which correlates well with its increased potency to induce filopodia. We also show that the molecular dynamic properties of F-BAR(2) at the membrane are partially dependent on F-Actin. Interestingly, acute phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] depletion in cells does not interfere with plasma membrane localization of F-BAR(2), which is compatible with our result showing that F-BAR(2) binds to a broad range of negatively-charged phospholipids present at the plasma membrane, including phosphatidylserine (PtdSer). Overall, our results provide novel insights into the functional diversity of the membrane deformation properties of this subclass of F-BAR-domains required for cell morphogenesis. PMID:22467852

  3. Shape coexistence in neutron-rich Sr isotopes : Coulomb excitation of $^{96}$Sr

    CERN Multimedia

    Clement, E; Siem, S; Czosnyka, T

    2007-01-01

    The nuclei in the mass region A $\\cong$ 100 around Sr and Zr show a dramatic change of the nuclear ground-state shape from near spherical for N $\\leq$ 58 to strongly deformed for N $\\geq$ 60. Theoretical calculations predict the coexistence of slightly oblate and strongly prolate deformed configurations in the transitional region. However, excited rotational structures based on the highly deformed configuration, which becomes the ground state at N = 60, are not firmly established in the lighter isotopes, and the earlier interpretation of a very abrupt change of shape has been challenged by recent experimental results in favor of a rather gradual change. We propose to study the electromagnetic properties of the neutron-rich nucleus $_{38}^{96}$Sr$_{58}$ by low-energy Coulomb excitation using the REX-ISOLDE facility and the MINIBALL detector array. Both transitional and diagonal matrix elements will be extracted, resulting in a complete description of the transition strengths and quadrupole moments of the low-l...

  4. Two-dimensional thermoelectric Seebeck coefficient of SrTiO3-based superlattices

    International Nuclear Information System (INIS)

    Ohta, Hiromichi

    2008-01-01

    This review provides the origin of the unusually large thermoelectric Seebeck coefficient vertical stroke S vertical stroke of a two-dimensional electron gas confined within a unit cell layer thickness (∝0.4 nm) of a SrTi 0.8 Nb 0.2 O 3 layer of artificial superlattices of SrTiO 3 /SrTi 0.8 Nb 0.2 O 3 [H. Ohta et al., Nature Mater. 6, 129 (2007)]. The vertical stroke S vertical stroke 2D values of the[(SrTiO 3 ) 17 /(SrTi 0.8 Nb 0.2 O 3 ) y ] 20 superlattice increase proportional to y -0.5 , and reach 290 μV K -1 (y=1) at room temperature, which is ∝5 times larger than that of the SrTi 0.8 Nb 0.2 O 3 bulk (vertical stroke S vertical stroke 3D =61 μVK -1 ), proving that the density of states in the ground state for SrTiO 3 increases in inverse proportion to y. The critical barrier thickness for quantum electron confinement is also clarified to be 6.25 nm (16 unit cells of SrTiO 3 ). Significant structural changes are not observed in the superlattice after annealing at 900 K in a vacuum. The value of vertical stroke S vertical stroke 2D of the superlattice gradually increases with temperature and reaches 450 μVK -1 at 900 K, which is ∝3 times larger than that of bulk SrTi 0.8 Nb 0.2 O 3 . These observations provide clear evidence that the [(SrTiO 3 ) 17 /(SrTi 0.8 Nb 0.2 O 3 ) 1 ] 20 superlattice is stable and exhibits a giant vertical stroke S vertical stroke even at high temperature. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Rb-Sr dating of sphalerites from Mississippi Valley-type (MVT) ore deposits

    Energy Technology Data Exchange (ETDEWEB)

    Nakai, S.; Halliday, A.N.; Kesler, S.E.; Jones, H.D. (Univ. of Michigan, Ann Arbor (United States)); Kyle, J.R. (Univ. of Texas, Austin (United States)); Lane, T.E. (Memorial Univ. of Newfoundland, St. John' s (Canada))

    1993-01-01

    Mississippi Valley-type (MVT) ore deposits are epigenetic carbonate-hosted Pb-Zn deposits that contain galena, sphalerite, fluorite, barite, dolomite, calcite, and quartz. Although they are thought to form from basinal brines, their exact origins are still unclear, partly because of the scarcity of reliable geochronological data. Rb-Sr dating of sphalerites has recently been shown to be a promising technique for the direct dating of ore minerals in MVT deposits. This paper reports the results of a reconnaissance study of sphalerites, their fluid inclusions, and associated minerals from MVT deposits of North America. Sphalerites from Immel mine, Mascot-Jefferson City district, east Tennessee, define a Rb-Sr age of 347 [plus minus] 20 Ma consistent with a Rb-Sr age of 377 [plus minus] 29 Ma for sphalerites from Coy mine in the same district, but inconsistent with models that ascribe their genesis to the effects of the late Paleozoic Alleghenian orogeny. Rb-Sr isotopic analyses of K-feldspar from Immel mine preclude the possibility that the Rb-Sr data reflect feldspar inclusions. Sphalerites from the main ore zone of Daniel's Harbour mine, Newfoundland, do not form a linear isochron and open behavior of the Rb-Sr system is suspected. Sphalerites from the Pine Point district, Northwest Territories, Canada, define a Rb-Sr age of 361 [plus minus] 13 Ma, indicating that the mineralization took place shortly after the deposition of the middle Devonian host carbonate rocks. These results are not compatible with mineralization models based on regional fluid migration related to early Tertiary Cordilleran deformation. Sphalerites from northern Arkansas have very low Rb and Sr concentrations (less than 0.1 ppm). The Rb-Sr data do not form isochrons and the sphalerites have higher [sup 87]Sr/[sup 86]Sr ratios than expected, given their Rb/Sr ratios and reasonable constraints on their ages. 58 refs., 7 figs., 2 tabs.

  6. Studies on the phase diagram of LiBr-SrBr2 system

    International Nuclear Information System (INIS)

    Mahendran, K.H.; Sujatha, K.; Sridharan, R.; Gnanasekaran, T.

    2003-01-01

    Binary LiBr-SrBr 2 system was investigated using differential scanning calorimetry (DSC) and the equilibrium phases at different compositions were identified using X-ray diffraction (XRD). This system has a compound LiSr 2 Br 5 , and exhibits a eutectic reaction between this compound and LiBr at 434 deg. C and the eutectic has a composition of 35 mol% SrBr 2 . The compound LiSr 2 Br 5 undergoes peritectic decomposition at 484 deg. C. From the DSC and XRD results, phase diagram of the LiBr-SrBr 2 system is constructed

  7. Lanthanide-doped Sr2YF7 nanoparticles: controlled synthesis, optical spectroscopy and biodetection

    Science.gov (United States)

    Yang, Yuhan; Tu, Datao; Zheng, Wei; Liu, Yongsheng; Huang, Ping; Ma, En; Li, Renfu; Chen, Xueyuan

    2014-09-01

    Sr2YF7, as an important matrix for trivalent lanthanide (Ln3+) ions to fabricate upconversion (UC) or downshifting (DS) phosphors, has been rarely reported. Herein, monodisperse and size-controllable tetragonal-phase Ln3+-doped Sr2YF7 nanoparticles (NPs) were synthesized via a facile thermal decomposition method. Upon excitation at 980 nm, UC luminescence properties of Sr2YF7:Ln3+/Yb3+ (Ln = Tm, Er) NPs were systematically surveyed. Particularly, after coating an inert Sr2YF7 shell, the UC luminescence intensities of Sr2YF7:Tm3+/Yb3+ and Sr2YF7:Er3+/Yb3+ NPs were enhanced by ~22 and 4 times, respectively. Furthermore, intense multicolor DS luminescence was also achieved in Ce3+/Tb3+ or Eu3+ doped Sr2YF7 NPs, with absolute quantum yields of 55.1% (Tb3+) and 11.2% (Eu3+). The luminescence lifetimes of 5D4 (Tb3+) and 5D0 (Eu3+) were determined to be 3.7 and 8.1 ms, respectively. By utilizing the long-lived luminescence of Ln3+ in these Sr2YF7 NPs, we demonstrated their application as sensitive heterogeneous time-resolved photoluminescence bioprobes to detect the protein of avidin and the tumor marker of the carcinoembryonic antigen (CEA) with their limits of detection down to 40.6 and 94.9 pM, and thus reveal the great potential of these Sr2YF7:Ln3+ nanoprobes in cancer diagnosis.Sr2YF7, as an important matrix for trivalent lanthanide (Ln3+) ions to fabricate upconversion (UC) or downshifting (DS) phosphors, has been rarely reported. Herein, monodisperse and size-controllable tetragonal-phase Ln3+-doped Sr2YF7 nanoparticles (NPs) were synthesized via a facile thermal decomposition method. Upon excitation at 980 nm, UC luminescence properties of Sr2YF7:Ln3+/Yb3+ (Ln = Tm, Er) NPs were systematically surveyed. Particularly, after coating an inert Sr2YF7 shell, the UC luminescence intensities of Sr2YF7:Tm3+/Yb3+ and Sr2YF7:Er3+/Yb3+ NPs were enhanced by ~22 and 4 times, respectively. Furthermore, intense multicolor DS luminescence was also achieved in Ce3+/Tb3+ or Eu3

  8. The Ca(PO3)2-Sr(PO3)2 system

    International Nuclear Information System (INIS)

    Bukhalova, G.A.; Tokman, I.A.

    1977-01-01

    Phase diagram of the system Ca(PO 3 ) 2 -Sr(PO 3 ) 2 has been studied and plotted with the aid of differential thermal, visual polythermal, X-ray analysis, and infrared spectroscopy. Continuous solid solutions are formed in the system with a minimum at 968 deg C and 25 mol.% of Sr(PO 3 ) 2 . Solid solutions decompose with the formation of about 30 mol.% of Sr(PO 3 ) 2

  9. Determination of the fraction of 90Sr extracting from bones during cooking

    International Nuclear Information System (INIS)

    Kunert, J.; Ziesak, H.

    1976-01-01

    Fresh, commercial cattle bones containing 600 pCi 90 Sr per kilogram were cooked in waters of different degrees of hardness according to an usual beef-tea recipe. After cooking, 90 Sr was also detected in the leftover meat (about 40 pCi per kilogram) adhering to the bones. The beef-tea contained about 1 pCi 90 Sr per litre corresponding to 0.5 to 0.7% of the total amount of 90 Sr which were found in fresh bones. Assuming a weekly consumption of 1 litre beef-tea and 50 g leftover meat, the annual ingestion of 90 Sr would be 160 pCi corresponding to 0.1 to 0.2% of the maximum permissible annual intake, or to 5% of the total 90 Sr dietary intake in 1974, respectively. (author)

  10. Molecular beam epitaxy of three-dimensional Dirac material Sr3PbO

    Science.gov (United States)

    Samal, D.; Nakamura, H.; Takagi, H.

    2016-07-01

    A series of anti-perovskites including Sr3PbO are recently predicted to be a three-dimensional Dirac material with a small mass gap, which may be a topological crystalline insulator. Here, we report the epitaxial growth of Sr3PbO thin films on LaAlO3 using molecular beam epitaxy. X-ray diffraction indicates (001) growth of Sr3PbO, where [110] of Sr3PbO matches [100] of LaAlO3. Measurements of the Sr3PbO films with parylene/Al capping layers reveal a metallic conduction with p-type carrier density of ˜1020 cm-3. The successful growth of high quality Sr3PbO film is an important step for the exploration of its unique topological properties.

  11. Phase study in Sr-Th-P-O system: Structural and thermal investigations of quaternary compounds

    International Nuclear Information System (INIS)

    Keskar, Meera; Phatak, Rohan; Sali, S.K.; Krishnan, K.; Dahale, N.D.; Kulkarni, N.K.; Kannan, S.

    2011-01-01

    The sub-solidus phase relations in Sr-Th-P-O quaternary system were determined at 1223 K in air. To confirm the formation and stability of reported phases, ternary and quaternary compounds in Sr-Th-O, Sr-P-O, Th-P-O and Sr-Th-P-O systems were synthesized by solid state reactions of SrCO 3 , ThO 2 and NH 4 H 2 PO 4 in desired molar proportions at 1223 K. A pseudo-ternary phase diagram of SrO-ThO 2 -P 2 O 5 system was drawn on the basis of the phase analysis of various phase mixtures and phase fields were established by powder X-ray diffraction. In the phase diagram, three quaternary compounds SrTh(PO 4 ) 2 , SrTh 4 (PO 4 ) 6 and Sr 7 Th(PO 4 ) 6 were identified. When heated in air at 1673 K, these compounds decompose to ThO 2 . Structures of SrTh(PO 4 ) 2 , SrTh 4 (PO 4 ) 6 and Sr 7 Th(PO 4 ) 6 were derived from X-ray powder data using the Rietveld refinement method. Thermal expansion behaviors of SrTh(PO 4 ) 2 , SrTh 4 (PO 4 ) 6 and Sr 7 Th(PO 4 ) 6 were investigated using high-temperature X-ray diffraction in the temperature range of 298-1273 K.

  12. The accumulation study of 90Sr in fish from a fishpond of northern Taiwan

    International Nuclear Information System (INIS)

    Lee, Pi-Fen; Wang, Jeng-Jong; Huang, Ju-Chuan

    2013-01-01

    Three kinds of fish from a natural fishpond in the north of Taiwan were collected and analyzed in this study. The three species were non-predatory Ctenopharyn odon idellus, predatory Aristichthys nobilis and predatory Mylopharyngodon piceus. The activity concentrations of 90 Sr in bone and edible flesh of fish, as well as in water and soil of fishpond were measured by using the radiochemical analysis. Additionally, the concentration of stable calcium in fish bone, [Ca] bone , and that of stable strontium in fish bone, [Sr] bone , were measured by ICP-AES. From the results, the concentration factors of 90 Sr, CF( 90 Sr), in fish bone was no statistic difference between non-predatory and predatory fish. Besides, the accumulation of 90 Sr in the non-predatory fish remarkably decreased with increasing the fish weight. As for the predatory fish, they both showed no statistically significant correlations between the 90 Sr activity concentration and the fish weight. Regarding the activity concentrations of 90 Sr in fish bone, all the fish were observed positively correlated with the measured [Sr] bone . - Highlights: • There was no difference in CF( 90 Sr) between non-predatory and predatory fish. • The 90 Sr in non-predatory fish bone decreased with increasing fish weight. • There was no correlation between 90 Sr in predatory fish bone and the fish weight. • The 90 Sr in fish bone increased with the increase of [Sr] bone

  13. Strontium isotope fractionation during strontianite (SrCO3) dissolution, precipitation and at equilibrium

    Science.gov (United States)

    Mavromatis, Vasileios; Harrison, Anna L.; Eisenhauer, Anton; Dietzel, Martin

    2017-12-01

    In this study we examine the behavior of stable Sr isotopes between strontianite [SrCO3] and reactive fluid during mineral dissolution, precipitation, and at chemical equilibrium. Experiments were performed in batch reactors at 25 °C in 0.01 M NaCl solutions wherein the pH was adjusted by bubbling of a water saturated gas phase of pure CO2 or atmospheric air. The equilibrium Sr isotope fractionation between strontianite and fluid after dissolution of the solid under 1 atm CO2 atmosphere was estimated as Δ88/86SrSrCO3-fluid = δ88/86Sr SrCO3 - δ88/86Srfluid = -0.05 ± 0.01‰. On the other hand, during strontianite precipitation, an enrichment of the fluid phase in 88Sr, the heavy isotopomer, was observed. The evolution of the δ88/86Srfluid during strontianite precipitation can be modeled using a Rayleigh distillation approach and the estimated, kinetically driven, fractionation factor αSrCO3-fluid between solid and fluid is calculated to be 0.99985 ± 0.00003 corresponding to Δ88/86SrSrCO3-fluid = -0.15‰. The obtained results further support that under chemical equilibrium conditions between solid and fluid a continuous exchange of isotopes occurs until the system approaches isotopic equilibrium. This isotopic exchange is not limited to the outer surface layer of the strontianite crystal, but extends to ∼7-8 unit cells below the crystal surface. The behavior of Sr isotopes in this study is in excellent agreement with the concept of dynamic equilibrium and it suggests that the time needed for achievement of chemical equilibrium is generally shorter compared to that for isotopic equilibrium. Thus it is suggested that in natural Sr-bearing carbonates an isotopic change may still occur close to thermodynamic equilibrium, despite no observable change in aqueous elemental concentrations. As such, a secondary and ongoing change of Sr isotope signals in carbonate minerals caused by isotopic re-equilibration with fluids has to be considered in order to use Sr

  14. Ca and Sr isotope records support ocean acidification during end-Permian mass extinction

    Science.gov (United States)

    Wang, J.; Jacobson, A. D.; Zhang, H.; Ramezani, J.; Sageman, B. B.; Hurtgen, M.; Bowring, S. A.; Shen, S.

    2017-12-01

    The end-Permian mass extinction represents the most devastating loss of biodiversity during the Phanerozoic. A negative carbon isotope (δ13C) excursion that accompanies the event suggests a significant perturbation to the global carbon cycle, likely induced by CO2 emissions during eruption of the Siberian Traps large igneous province. The carbon cycle is linked with the Ca and Sr cycles through chemical weathering and carbonate precipitation. Therefore, analyses of Ca (δ44/40Ca), radiogenic Sr (87Sr/86Sr), and stable Sr (δ88/86Sr) isotope abundance variations in marine carbonate rocks spanning the Permian-Triassic Boundary (PTB) can reveal key information about biogeochemical changes that occurred during this time. We report δ44/40Ca, 87Sr/86Sr, and δ88/86Sr records analyzed by TIMS for the Meishan and Dajiang sections in China. δ44/40Ca values exhibit similar patterns in both sections. The values remain unchanged across the extinction event layer (EXT) and then decrease by 0.20‰ before increasing by 0.20‰ to 0.40‰ around the PTB. In the Meishan section, 87Sr/86Sr ratios increase after the EXT and return to pre-excursion levels by the PTB. Simultaneously, δ88/86Sr values decrease by 0.12‰ across the EXT and increase by 0.08‰ by the PTB. The patterns of our data support the hypothesis that elevated atmospheric CO2 levels enhanced chemical weathering inputs and might have caused transient ocean acidification, with an "alkalinity overshoot" and increased carbonate deposition occurring after the extinction. Additional measurements and model calculations are underway to help refine and improve these preliminary interpretations.

  15. Crystal growth and scintillation properties of Pr-doped SrI2 single crystals

    Science.gov (United States)

    Yokota, Yuui; Ito, Tomoki; Yoshino, Masao; Yamaji, Akihiro; Ohashi, Yuji; Kurosawa, Shunsuke; Kamada, Kei; Yoshikawa, Akira

    2018-04-01

    Pr-doped SrI2 (Pr:SrI2) single crystals with various Pr concentrations were grown by the halide-micro-pulling-down (H-μ-PD) method, and the scintillation properties were investigated. Pr1%:SrI2 single crystal with high transparency could be grown by the H-μ-PD method while Pr2, 3 and 5%:SrI2 single crystals included some cracks and opaque parts. In the photoluminescence spectrum of the Pr1%:SrI2 single crystal, an emission peak originated from the Pr3+ ion was observed around 435 nm while the radioluminescence spectra showed an emission peak around 535 nm for the undoped SrI2 and Pr:SrI2 single crystals. Light yields of Pr1, 2, 3 and 5%:SrI2 single crystals under γ-ray irradiation were 7700, 8700, 7200 and 6700 photons/MeV, respectively. Decay times of Pr1 and 2%:SrI2 single crystals under γ-ray irradiation were 55.9 and 35.0 ns of the fast decay component, and 435 and 408 ns of the slow decay component, respectively.

  16. Adenovirus DNA binding protein inhibits SrCap-activated CBP and CREB-mediated transcription

    International Nuclear Information System (INIS)

    Xu Xiequn; Tarakanova, Vera; Chrivia, John; Yaciuk, Peter

    2003-01-01

    The SNF2-related CBP activator protein (SrCap) is a potent activator of transcription mediated by CBP and CREB. We have previously demonstrated that the Adenovirus 2 DNA Binding Protein (DBP) binds to SrCap and inhibits the transcription mediated by the carboxyl-terminal region of SrCap (amino acids 1275-2971). We report here that DBP inhibits the ability of full-length SrCap (1-2971) to activate transcription mediated by Gal-CREB and Gal-CBP. In addition, DBP also inhibits the ability of SrCap to enhance Protein Kinase A (PKA) activated transcription of the enkaphalin promoter. DBP was found to dramatically inhibit transcription of a mammalian two-hybrid system that was dependent on the interaction of SrCap and CBP binding domains. We also found that DBP has no effect on transcription mediated by a transcriptional activator that is not related to SrCap, indicating that our reported transcriptional inhibition is specific for SrCap and not due to nonspecific effects of DBP's DNA binding activity on the CAT reporter plasmid. Taken together, these results suggest a model in which DBP inhibits cellular transcription mediated by the interaction between SrCap and CBP

  17. Experiment data report for semiscale Mod-2A primary feed and bleed experiment series (Tests S-SR-1 and S-SR-2)

    International Nuclear Information System (INIS)

    Fogdall, S.P.

    1982-10-01

    This report presents test data recorded for Tests S-SR-1 and S-SR-2 of the Semiscale Mod-2A Primary Feed and Bleed Tests. These tests are part of a series of Semiscale tests that investigate the thermal-hydraulic phenomena resulting from a hypothesized loss-of-coolant accident (LOCA) or abnormal operating transient. These tests provide experimental data for assessing the analytical capability of computer codes used in LOCA and operational transient analysis. The primary objectives of Tests S-SR-1 and -2 were to provide data on primary system recovery through the use of primary feed and bleed cooling, with no heat transfer to the secondaries. Data was obtained using high- and low-head pump curves for the safety injection (SI) pumps. This report presents the uninterpreted data from Tests S-SR-1 and -2 for analysis. The data, presented as graphs in engineering units, have been analyzed only to the extent necessary to ensure that they are reasonable and consistent

  18. Knockdown expression and hepatic deficiency reveal anatheroprotective role for SR-BI in liver and peripheral tissues

    Energy Technology Data Exchange (ETDEWEB)

    Huby, Thierry; Doucet, Chantal; Dachet, Christiane; Ouzilleau,Betty; Ueda, Yukihiko; Afzal, Veena; Rubin, Edward; Chapman, M. John; Lesnik, Philippe

    2006-07-18

    Scavenger receptor SR-BI has been implicated inHDL-dependent atheroprotective mechanisms. We report the generation of anSR-BI conditional knockout mouse model in which SR-BI gene targeting byloxP site insertion produced a hypomorphic allele (hypomSR-BI).Attenuated SR-BI expression in hypomSR-BI mice resulted in 2-foldelevation in plasma total cholesterol (TC) levels. Cre-mediated SR-BIgene inactivation of the hypomorphic SR-BI allele in hepatocytes(hypomSR-BI-KOliver) was associated with high plasma TC concentrations,increased plasma free cholesterol/TC (FC/TC) ratio, and alipoprotein-cholesterol profile typical of SR-BI-/- mice. Plasma TClevels were increased 2-fold in hypomSR-BI and control mice fed anatherogenic diet, whereas hypomSR-BI-KOliver and SR-BI-/- mice developedsevere hypercholesterolemia due to accumulation of FC-rich, VLDL-sizedparticles. Atherosclerosis in hypomSR-BI mice was enhanced (2.5-fold)compared with that in controls, but to a much lower degree than inhypomSR-BI-KOliver (32-fold) and SR-BI-/- (48-fold) mice. The lattermodels did not differ in either plasma lipid levels or in the capacity ofVLDL-sized lipoproteins to induce macrophage cholesterol loading.However, reduced atherosclerosis in hypomSR-BI-KOliver mice wasassociated with decreased lesional macrophage content as compared withthat in SR-BI-/- mice. These data imply that, in addition to its majoratheroprotective role in liver, SR-BI may exert an antiatherogenic rolein extrahepatic tissues.

  19. Correlated electronic properties of different SrIrO{sub 3}/SrTiO{sub 3} heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Kraberger, Gernot J.; Aichhorn, Markus [Institute of Theoretical and Computational Physics, NAWI Graz, Graz University of Technology, Petersgasse 16, 8010 Graz (Austria)

    2016-07-01

    Strontium iridates are materials that combine strong electronic correlations with pronounced spin-orbit coupling, giving rise to fascinating physical properties. Strategies to purposefully influence and design these materials are a crucial step to further advance this field. A highly promising candidate for achieving this goal is the formation of heterostructures with other materials. Motivated by this quest, we perform calculations within the DFT+DMFT framework to investigate how the geometry of heterostructures of perovskite SrIrO{sub 3} with SrTiO{sub 3} influences their correlated electronic structure. We explore the differences between (001)- and (111)-stacked heterostructures, where the latter are particularly interesting because they form buckled honeycomb lattices that have non-trivial topological properties. For the (001)-heterostructures the effect of varying the thickness of the SrIrO{sub 3} layers, and thus their effective dimensionality, are studied. As an important ingredient we have to consider the effect of lattice distortions - in the form of a rotation of the oxygen cages - on the electronic correlations. We argue how the interplay of all these factors together allows a targeted modification of the electronic properties of the material.

  20. Electrochemical characterization and redox behavior of Nb-doped SrTiO3

    DEFF Research Database (Denmark)

    Blennow Tullmar, Peter; Kammer Hansen, Kent; Wallenberg, L. Reine

    2009-01-01

    Sr-vacancy compensated Nb-doped SrTiO3 with the nominal composition Sr0.94Ti0.9Nb0.1O3 has been evaluated as a solid oxide fuel cell (SOFC) anode material in terms of redox stability and electrochemical properties. Sr0.94Ti0.9Nb0.1O3 has been synthesized with a recently developed modified glycine......-nitrate process. The phase purity and redox behavior have been analyzed with XRD and TGA. The electrochemical properties of Sr0.94Ti0.9Nb0.1O3 and a composite electrode of Sr0.94Ti0.9Nb0.1O3/YSZ have been investigated by electrochemical impedance spectroscopy (EIS) on cone shaped electrodes and on electrodes...... in a symmetrical cell configuration. The experiments indicated that the Nb-doped SrTiO3 electrodes were redox stable and showed a potential ability to be used as a part of a SOFC anode. The electrochemical activity appeared to be governed by the concentration of defect species (especially Ti3+ and V-0...

  1. Sr-Al-Si co-segregated regions in eutectic Si phase of Sr-modified Al-10Si alloy.

    Science.gov (United States)

    Timpel, M; Wanderka, N; Schlesiger, R; Yamamoto, T; Isheim, D; Schmitz, G; Matsumura, S; Banhart, J

    2013-09-01

    The addition of 200 ppm strontium to an Al-10 wt% Si casting alloy changes the morphology of the eutectic silicon phase from coarse plate-like to fine fibrous networks. In order to clarify this modification mechanism the location of Sr within the eutectic Si phase has been investigated by a combination of high-resolution methods. Whereas three-dimensional atom probe tomography allows us to visualise the distribution of Sr on the atomic scale and to analyse its local enrichment, transmission electron microscopy yields information about the crystallographic nature of segregated regions. Segregations with two kinds of morphologies were found at the intersections of Si twin lamellae: Sr-Al-Si co-segregations of rod-like morphology and Al-rich regions of spherical morphology. Both are responsible for the formation of a high density of multiple twins and promote the anisotropic growth of the eutectic Si phase in specific crystallographic directions during solidification. The experimental findings are related to the previously postulated mechanism of "impurity induced twinning". Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Accumulation of 90Sr to cattle and horse bones in Hokkaido

    International Nuclear Information System (INIS)

    Chikayama, Yukio; Yagi, Yukio; Shiono, Hiroki; Watanabe, Atsushi; Miyamoto, Toru

    1999-01-01

    Since herbivores like cattle and horse take plants contaminated by radioactive fallout, 90 Sr in their bones can be a excellent biological measure of environmental radioactive pollution. The authors continued and reported such investigations on 90 Sr accumulation from 1957 and this paper described the summary from 1987 to 1996. Samples of 225 cattle bones and 257 horse bones were treated at 900 deg C for 5-6 hr. 90 Y extracted by (2-ethylhexyl)phosphoric acid from the samples was measured in the low back-ground gas-flow counter and the concentrations (mBq/g·Ca) of the parent nuclide 90 Sr were estimated. Bone level of 90 Sr, after peaked at 1965-1966, had deceased thereafter and became the minimum at 1995 in the cattle and at 1996 in the horse. Horse bones contained the higher 90 Sr level than cattle's. There was a positive correlation between the age and 90 Sr concentration. In conclusion, the environmental radioactivity due to the fallout is low at present in Hokkaido. (K.H.)

  3. Imaging and tuning polarity at SrTiO3 domain walls

    Science.gov (United States)

    Frenkel, Yiftach; Haham, Noam; Shperber, Yishai; Bell, Christopher; Xie, Yanwu; Chen, Zhuoyu; Hikita, Yasuyuki; Hwang, Harold Y.; Salje, Ekhard K. H.; Kalisky, Beena

    2017-12-01

    Electrostatic fields tune the ground state of interfaces between complex oxide materials. Electronic properties, such as conductivity and superconductivity, can be tuned and then used to create and control circuit elements and gate-defined devices. Here we show that naturally occurring twin boundaries, with properties that are different from their surrounding bulk, can tune the LaAlO3/SrTiO3 interface 2DEG at the nanoscale. In particular, SrTiO3 domain boundaries have the unusual distinction of remaining highly mobile down to low temperatures, and were recently suggested to be polar. Here we apply localized pressure to an individual SrTiO3 twin boundary and detect a change in LaAlO3/SrTiO3 interface current distribution. Our data directly confirm the existence of polarity at the twin boundaries, and demonstrate that they can serve as effective tunable gates. As the location of SrTiO3 domain walls can be controlled using external field stimuli, our findings suggest a novel approach to manipulate SrTiO3-based devices on the nanoscale.

  4. Epitaxial growth and electronic structure of oxyhydride SrVO2H thin films

    Science.gov (United States)

    Katayama, Tsukasa; Chikamatsu, Akira; Yamada, Keisuke; Shigematsu, Kei; Onozuka, Tomoya; Minohara, Makoto; Kumigashira, Hiroshi; Ikenaga, Eiji; Hasegawa, Tetsuya

    2016-08-01

    Oxyhydride SrVO2H epitaxial thin films were fabricated on SrTiO3 substrates via topotactic hydridation of oxide SrVO3 films using CaH2. Structural and composition analyses suggested that the SrVO2H film possessed one-dimensionally ordered V-H--V bonds along the out-of-plane direction. The synthesis temperature could be lowered by reducing the film thickness, and the SrVO2H film was reversible to SrVO3 by oxidation through annealing in air. Photoemission and X-ray absorption spectroscopy measurements revealed the V3+ valence state in the SrVO2H film, indicating that the hydrogen existed as hydride. Furthermore, the electronic density of states was highly suppressed at the Fermi energy, consistent with the prediction that tetragonal distortion induces metal to insulation transition.

  5. Sr2CeO4: Electronic and structural properties

    International Nuclear Information System (INIS)

    Rocha, Leonardo A.; Schiavon, Marco A.; Nascimento, Clebio S.; Guimarães, Luciana; Góes, Márcio S.; Pires, Ana M.; Paiva-Santos, Carlos O.

    2014-01-01

    Highlights: • Sr 2 CeO 4 it was obtained from the heat treatment of Ce 3+ -doped strontium oxalate. • Rietveld analysis made it possible to obtain information about crystalline structure. • Experimental band gap value was compared with theoretical obtained by Sparkle/PM7. • The materials obtained shows intense photoluminescence and scintillator properties. - Abstract: This work presents on the preparation and photoluminescent properties of Sr 2 CeO 4 obtained from the heat treatment of Ce(III)-doped strontium oxalate (10, 25 and 33 mol%). The oxalate precursors were heat treated at 1100 °C for 12 h. The structure of this photoluminescent material was evaluated by the Rietveld method. The route used in this work to prepare the materials showed to be viable when compared to other synthesis reported in the literature. The Sr 2 CeO 4 material showed a broad and intense band emission with a maximum around 485 nm. The quantitative phase analysis showed that the Sr 2 CeO 4 photoluminescent phase is the majority one compared to the impurity phases of SrCeO 3 and SrCO 3 . From all results it was possible to verify a complete elimination of the CeO 2 phase for the sample obtained from the heat treatment of oxalate precursor containing 33 mol% of cerium(III). The material showed excellent properties for possible candidate as scintillator materials, and in the improvement of efficiency of solar cells when excited in the UV–vis region. The CIE chromaticity diagram it is also reported in this work

  6. Investigating the hydrological significance of stalagmite geochemistry (Mg, Sr) using Sr isotope and particulate element records across the Late Glacial-to-Holocene transition

    Science.gov (United States)

    Belli, R.; Borsato, A.; Frisia, S.; Drysdale, R.; Maas, R.; Greig, A.

    2017-02-01

    The trace element and Sr isotope records in two coeval stalagmites characterized by different growth rates and flow regimes at Savi cave (Grotta Savi, NE Italy) reveal different sources and incorporation mechanisms for Mg and Sr. Mg is sourced primarily from dissolved cave host rock while particulate Mg derived from soil plays a subordinate role. The presence of particulate-borne Mg is inferred from the co-variation of Mg and particle-associated elements (Th, Al and Mn) which are preferentially concentrated in open columnar calcite layers. Variation in Mg concentrations corrected for particle-influenced components, the Mgc parameter, is controlled by water-rock interaction, with higher and lower Mgc during dry and wet phases, respectively. This is thought to reflect incongruent dissolution of Mg-rich phases. Correction of Sr concentrations for contributions from airborne exogenic Sr, based on 87Sr/86Sr ratios, yields the bedrock-only contribution (Src). Src variation in stalagmite calcite is influenced by speleothem growth rate and by variation of the calcite-water Sr partitioning in wet and dry phases, and only to a minor extent by incongruent dissolution of Mg-rich phases. Concentration profiles for Mgc and Srcg (corrected for growth rate effects) show inverse correlations and are inferred to show hydrological significance which is captured in a hydrological index, HI. We suggest HI provides robust information on water-rock interaction related to hydrological changes and can be utilized in both wet and semi-arid environments, provided the corrections for soil Mg and exogenic Sr can be applied with confidence. Application of the HI index allows correction of Grotta Savi oxygen isotope data, to yield a δ18Oc time series that shows when changes in moisture sources and atmospheric reorganization, or changes in moisture amount, were significant. This is especially evident during the Younger Dryas (YD). The Savi record supports the concept of a two-phase YD, marked by

  7. Precessional control of Sr ratios in marginal basins during the Messinian Salinity Crisis?

    NARCIS (Netherlands)

    Topper, R.P.M.; Lugli, S.; Manzi, V.; Roveri, M.; Meijer, P.Th.

    Based on 87Sr/86Sr data of the Primary Lower Gypsum (PLG) deposits in the Vena del Gesso basin—a marginal basin of the Mediterranean during the Messinian Salinity Crisis—a correlation between 87Sr/86Sr values and precessional forcing has recently been proposed but not yet confirmed. In this study, a

  8. Passer de la connaissance à l'action pour résoudre des problèmes complexes : aperçu de l'examen de neuf cas internationaux

    Directory of Open Access Journals (Sweden)

    B. L. Riley

    2015-01-01

    Full Text Available Introduction: La résolution de problèmes complexes du type de la prévention des maladies chroniques présente des défis particuliers pour la création et le transfert de connaissances, soit le passage de la connaissance à l'action (PCA. Les approches axées sur le PCA respectant les principes de la pensée systémique sont jugées prometteuses,mais les stratégies pour les mettre en place ne sont pas bien comprises. Dans cet article, nous présentons les résultats d'une analyse de plusieurs approches systémiques axées sur le PCA dans le but de déterminer comment optimiser leur mise en œuvre et leur efficacité. Méthodologie: Un groupe consultatif de cinq personnes a choisi neuf initiatives représentant une diversité d'enjeux et de formes organisationnelles. Pour chaque cas, l'information a été recueillie à partir de documents et par l'entremise d'entrevues téléphoniques avec des personnes-ressources de chaque organisation. Aprés la vérification des descriptions de cas, une analyse inductive a été effectuée à la fois pour chaque cas et entre les cas. Résultats: Ces cas ont révélé cinq lignes directrices permettant de passer de la conception de systémes de PCA à leur mise en œuvre : établir et entretenir des relations, coproduire et organiser les connaissances, créer des boucles de rétroaction, les encadrer comme des interventions systémiques plutôt que comme des projets et envisager des variations dans le temps et selon les lieux. Conclusion: Les résultats de cette analyse contextuelle constituent un départ modeste pour transformer en résultats concrets les concepts systémiques de PCA. L'utilisation des stratégies mises au jour pourrait améliorer le PCA pour la résolution de problèmes complexes en matière de santé publique. Les stratégies elles-mêmes pourront bénéficier de l'évolution d'une science visant à comprendre l'adaptation et l'apprentissage constant des politiques et des interventions

  9. Strain dependence of interfacial antiferromagnetic coupling in La0.7Sr0.3MnO3/SrRuO3 superlattices

    Science.gov (United States)

    Das, Sujit; Herklotz, Andreas; Pippel, Eckhard; Guo, Er-Jia; Rata, Diana; Dörr, Kathrin

    2015-03-01

    We have investigated the magnetic response of La0.7Sr0.3MnO3/SrRuO3 superlattices to biaxial in-plane strain applied in-situ. Superlattices grown on piezoelectric substrates of 0.72PbMg1/3Nb2/3O3-0.28PbTiO3(001) (PMN-PT) show strong antiferromagnetic coupling of the two ferromagnetic components. The coupling field of μ0HAF = 1.8 T is found to change by μ0 ΔHAF / Δɛ ~ -520 mT %-1 under reversible biaxial strain (Δɛ) at 80 K in a [La0.7Sr0.3MnO3(22 Å)/SrRuO3(55 Å)]15 superlattice. This reveals a significant strain effect on interfacial coupling. The applied in-plane compression enhances the ferromagnetic order in the manganite layers which are under as-grown tensile strain. It is thus difficult to disentangle the contributions from strain-dependent antiferromagnetic Mn-O-Ru interface coupling and Mn-O-Mn ferromagnetic double exchange near the interface, since the enhanced magnetic order of Mn spins leads to a larger net coupling of SrRuO3 layers at the interface. We discuss our experimental findings taken into account both the strain-dependent orbital occupation in a single-ion picture and the enhanced Mn order at the interface. This work was supported by the DFG within the Collaborative Research Center SFB 762 ``Functionality of Oxide Interfaces.''

  10. On the μSR activity at LNP JINR phasotron

    International Nuclear Information System (INIS)

    Gurevich, I.I.; Duginov, V.N.; Firsov, V.G.

    1992-01-01

    The current state of μSR activity at LNR JINR phasotron is presented, including short description of experimental facilities. The possible trends of μSR investigation for future work are outlined. The list of main publications (1987-1992) is included. 35 refs.; 1 fig

  11. [Ag25(SR)18]¯: The ‘Golden’ Silver Nanoparticle

    KAUST Repository

    Joshi, Chakra Prasad

    2015-08-31

    Silver nanoparticles with an atomically precise molecular formula [Ag25(SR)18]¯ (‒SR: thiolate) are synthesized and their single-crystal structure is determined. This synthesized nanocluster is the only silver nanoparticle that has a virtually identical analogue in gold, i.e., [Au25(SR)18]¯, in terms of number of metal atoms, ligand count, super-atom electronic configuration, and atomic arrangement. Furthermore, both [Ag25(SR)18]¯ and its gold analogue share a number of features in their optical absorption spectra. This unprecedented molecular synthesis in silver to mimic gold offers the first model nanoparticle platform to investigate the centuries-old problem of understanding the fundamental differences between silver and gold in terms of nobility, catalytic activity, and optical property.

  12. [Ag25(SR)18]¯: The ‘Golden’ Silver Nanoparticle

    KAUST Repository

    Joshi, Chakra Prasad; Bootharaju, Megalamane Siddaramappa; Alhilaly, Mohammad J.; Bakr, Osman

    2015-01-01

    Silver nanoparticles with an atomically precise molecular formula [Ag25(SR)18]¯ (‒SR: thiolate) are synthesized and their single-crystal structure is determined. This synthesized nanocluster is the only silver nanoparticle that has a virtually identical analogue in gold, i.e., [Au25(SR)18]¯, in terms of number of metal atoms, ligand count, super-atom electronic configuration, and atomic arrangement. Furthermore, both [Ag25(SR)18]¯ and its gold analogue share a number of features in their optical absorption spectra. This unprecedented molecular synthesis in silver to mimic gold offers the first model nanoparticle platform to investigate the centuries-old problem of understanding the fundamental differences between silver and gold in terms of nobility, catalytic activity, and optical property.

  13. Cu-NMR study on disordered Sr14Cu24O41

    International Nuclear Information System (INIS)

    Ohsugi, S.; Matsumoto, S.; Kitaoka, Y.; Matsuda, M.; Uehara, M.; Akimitsu, J.; Nagata, T.

    2002-01-01

    The ladder-Cu NMR spectrum of a structural disordered single crystal Sr 14 Cu 24 O 41 (Sr14-B) under a magnetic field H∝11 T gradually splits into two spectra with Curie-like broadening as T decreases from T SP ∝150 K. Short-range (SR) staggered polarization (SP) on the ladder planes, originating from single-hole localization, occurs. The separation of the Sr14-B spectrum ΔH deviates from the Curie-like T dependence below 20 K. This assures that spontaneous moments appear below T N ∝20 K in H∝11 T. (orig.)

  14. Permian alkali granitoids of the transbaikal region (new Rb-Sr dates)

    Energy Technology Data Exchange (ETDEWEB)

    Sukhanov, M K; Ryakhovskij, V M; Abramov, A V

    1984-01-01

    Rubidium-strontium isotopic investigations of granitoids from Khorinsk and Middle Oninsk massifs were conducted. Isochrones for two chief-modifications of rocks - subalkaline syenites and alkaline granites-were constructed. The age of syenites is determined to be (293 + 20) x 10/sup 6/ at (/sup 87/Sr//sup 86/Sr)/sub 0/=0.7044 +- 0.0106 that of alkaline granites - (253 +- 3) x 10/sup 6/ at (/sup 87/Sr//sup 86/Sr)/sub 0/=0.7077 +- 0.0033. Analytical data for determination of rubidium-strontium age of rocks of the mentioned massits are presented as well.

  15. Phase diagrams for systems Cu2S-AIIS (AII=Mg, Ca, Sr, Ba)

    International Nuclear Information System (INIS)

    Andreev, O.V.; Sikerina, N.V.; Solov'eva, A.V.

    2005-01-01

    By the methods of physicochemical analysis phase diagrams of Cu 2 S-A II S (A II =Mg, Ca, Sr, Ba) systems are studied. The system Cu 2 S-SrS is of eutectic type with eutectic coordinates 1095 K and 21.5 mol.% of SrS. Solubility of SrS in Cu 2 S is 2 mol.% at 1095 K. Regularities of phase diagram changes of Cu 2 S-A II S (A II =Mg, Ca, Sr, Ba) system are determined. Thermodynamic analysis is done [ru

  16. Interim data report for the safety assessment SR-Can

    International Nuclear Information System (INIS)

    Vahlund, Fredrik; Andersson, Johan

    2004-08-01

    This document is the interim data report in the project SR-Can. The purpose of the data report is to present input data, with uncertainty estimates, for the SR-Can assessment calculations. Besides input data, the report also describes the standardised procedures used when deriving the input data and the corresponding uncertainty estimates. However, in the present interim version of the report (written in the initial stage of the project when site characterisation has yet not been completed) the standardised procedures have not been possible to apply for most of the data and, in order to present a compilation of the data used in the assessment, much of the input data is presented without following the standardised procedures. This will however be changed for the final version of the SR-Can data report, in order to show the methodology that will be used in the final version one example of how input data will be presented is included (migration data for buffer) . The recommended input data for the assessment calculations are, for the interim version, mainly based on SR 97 Beberg data, these are merely presented without any background or uncertainty discussion (this is presented in the SR 97 data report)

  17. Function modification of SR-PSOX by point mutations of basic amino acids

    Directory of Open Access Journals (Sweden)

    Chen Chunxia

    2011-04-01

    Full Text Available Abstract Background Atherosclerosis (AS is a common cardiovascular disease. Transformation of macrophages to form foam cells by internalizing modified low density-lipoprotein (LDL via scavenger receptor (SR is a key pathogenic process in the onset of AS. It has been demonstrated that SR-PSOX functions as either a scavenger receptor for uptake of atherogenic lipoproteins and bacteria or a membrane-anchored chemokine for adhesion of macrophages and T-cells to the endothelium. Therefore, SR-PSOX plays an important role in the development of AS. In this study the key basic amino acids in the chemokine domain of SR-PSOX have been identified for its functions. Results A cell model to study the functions of SR-PSOX was successfully established. Based on the cell model, a series of mutants of human SR-PSOX were constructed by replacing the single basic amino acid residue in the non-conservative region of the chemokine domain (arginine 62, arginine 78, histidine 80, arginine 82, histidine 85, lysine 105, lysine 119, histidine 123 with alanine (designated as R62A, R78A, H80A, R82A, H85A, K105A, K119A and H123A, respectively. Functional studies showed that the mutants with H80A, H85A, and K105A significantly increased the activities of oxLDL uptake and bacterial phagocytosis compared with the wild-type SR-PSOX. In addition, we have also found that mutagenesis of either of those amino acids strongly reduced the adhesive activity of SR-PSOX by using a highly non-overlapping set of basic amino acid residues. Conclusion Our study demonstrates that basic amino acid residues in the non-conservative region of the chemokine domain of SR-PSOX are critical for its functions. Mutation of H80, H85, and K105 is responsible for increasing SR-PSOX binding with oxLDL and bacteria. All the basic amino acids in this region are important in the cells adhesion via SR-PSOX. These findings suggest that mutagenesis of the basic amino acids in the chemokine domain of SR-PSOX may

  18. Effect of Sr doping on LaTiO3 thin films

    International Nuclear Information System (INIS)

    Vilquin, B.; Kanki, T.; Yanagida, T.; Tanaka, H.; Kawai, T.

    2005-01-01

    We report on the electric properties of La 1-x Sr x TiO 3 (0 ≤ x ≤ 0.5) thin films fabricated by pulsed laser deposition method. Crystallographic measurement of the thin films showed the epitaxial c-axis perovskite structure. The electric property of LaTiO 3 thin film, which is a typical Mott insulative material in bulk, showed insulative behaviour, while the Sr-doped films showed metallic conduction suffering electron-electron scattering. Below x = 0.1, the major carrier type was identified to be hole, and switched to electron with further increasing Sr-doping above x = 0.15. In fact, the switching from p-type to n-type for La 1-x Sr x TiO 3 thin films is first demonstrated in this study. The transition suggests that effective Coulomb gap vanishes due to over-additional Sr doping

  19. Quantum Logic with Composite Pulse Sequences on Sr^+

    Science.gov (United States)

    Shewmon, Ruth; Labaziewicz, Jaroslaw; Ge, Yufei; Wang, Shannon; Chuang, Isaac L.

    2008-03-01

    The optical 5S1/2->4D1/2 transition in Sr^+ is an attractive qubit because it can be addressed by diode lasers, which are relatively inexpensive and easy to operate. We characterize single-qubit rotations as well as a CNOT gate on a Sr^+ ion in a surface electrode Paul trap. To improve these operations, the frequency of the clock laser is stabilized to a high-finesse optical cavity. The resulting linewidth of the laser is approximately 300Hz. Composite pulse sequences, a technique adapted from NMR, have been shown to reduce the effects of systematic errors in a variety of quantum systems. We demonstrate several composite sequences that improve the fidelity of quantum logic operations on Sr^+.

  20. Rb-Sr isochronous age of Vepor pluton granitoids

    International Nuclear Information System (INIS)

    Bagdasaryan, G.P.; Gykasyan, R.Kh.; Cambel, B.

    1986-01-01

    The result are presented of geochronological investigations of the Vepor pluton granitoids by the Rb-Sr isochronous method. The results prove the Variscan age of granodiorite magmatism of the Sihla type (387±27 m.y.) and the Early Variscan age of leucocratic granitoids of the Vepor and the Ipel types (284±22 m.y.). Since the initial ratio of 87 Sr/ 86 Sr in granitoids of the Sihla type is 0.7054 and of the Vepor type 0.7060, it can be assumed that during the formation of the granitoids of veporides there was an increased supply of matter from the main source affecting genesis of granitoids. The results prove a polyphase character of the Variscan granitoids of Veporicum. (author)

  1. Phase equilibrium in Al-Li-Ca(Sr, Ba) systems at 423 K

    International Nuclear Information System (INIS)

    Ganieva, N.I.; Nazarov, Kh.M.; Ganiev, I.N.

    1999-01-01

    The isothermic cross section of the Al-Li-Ca(Sr, Ba) systems at 423 K is obtained. It is shown that the Al-Li-Sr ternary system as well as the Li-Sr binary system differ by nature of components in interaction from the Al-Li-Ca(Ba) systems. This is obvious by formation of the SrAl 2 Li 2 ternary intermetallide, which is not observed in the systems with participation of barium and calcium [ru

  2. Enthalpy increment measurements of Sr3Zr2O7(s) and Sr4Zr3O10(s)

    International Nuclear Information System (INIS)

    Banerjee, A.; Dash, S.; Prasad, R.; Venugopal, V.

    1998-01-01

    Enthalpy increment measurements on Sr 3 Zr 2 O 7 (s) and Sr 4 Zr 3 O 10 (s) were carried out using a Calvet micro-calorimeter. The enthalpy increment values were least squares analyzed with the constraints that H 0 (T)-H 0 (298.15 K) at 298.15 K equals to zero and C p 0 (298.15 K) equals to the estimated value. The dependence of enthalpy increment with temperature is given. (orig.)

  3. Fast and sensitive determination of Sr-90 and SR-89 activity in milk by ion-chromatography and liquid scintillation

    International Nuclear Information System (INIS)

    Figueiredo, V.; Herrmann, A.

    1992-01-01

    A method for fast and exact determination of both strontium isotopes in milk and other foodstuffs, combination high performance ion chromatographic separation with by liquid scintillation counting, which enables the desired results to be obtained with very satisfactory precision and reproducibility within 24 hours, has been developed. The lowest detectable activity lies by 3 Bq/liter for Sr-90 and 1 Bq/liter for Sr-89 which is satisfactory for assessing a situation in a time crisis. (author)

  4. Urinary 90Sr concentration in occupationally exposed and nonexposed persons in Austria

    International Nuclear Information System (INIS)

    Irlweck, K.; Streit, S.

    1979-01-01

    Personnel monitoring at Seibersdorf Research Centre includes analysis of 90 Sr in urine of employees who handle low-level radioactive wastes. Results for the two year period 1976-77 are reported. 90 Sr concentrations were mainly between 0.5 and 5.0pCi/l, except in the cases of two employees who incorporated 90 Sr as a result of an accident. Urine samples from 21 non-exposed persons not employed at Seibersdorf all gave results below 2pCi/l. These results agree with a 90 Sr concentration of 0.2-2.0pCi/l of urine estimated from global fallout data. If individual differences, e.g. in metabolism, diet etc. are taken into account, it is concluded that a 90 Sr incorporation above fallout level should be assumed with certainty only if the 90 Sr concentration exceeds 5pCi/l of urine. (author)

  5. Study on Sr-Nd isotopes of mesozoic-cenozoic granites in Qinghai-Tibetan plateau

    International Nuclear Information System (INIS)

    Qiu Ruizhao; Deng Jinfu; Zhou Su; Xiao Qinghui; Cai Zhiyong

    2003-01-01

    Mesozoic-Cenozoic magmatic activities were intensive in Qinghai-Tibetan plateau. Nd-Sr isotopic compositions of representative granitic plutons in western Qinghai-Tibetan plateau are reported in this paper. Combining with past isotopic data, which has reported in eastern Qinghai-Tibetan plateau, Sr-Nd isotopic compositions and material source and genesis of Mesozoic and Cenozoic granites in Qinghai-Tibetan plateau have been studied. The research result indicates there are three types of granite existing in Qinghai-Tibetan plateau, the granites of Late stage of Yanshan Period which distributing on north and south boundary of Gandes block (namely in north and south granitic belts of Dangdes) and cause of oceanic crust subduction, have ( 87 Sr/ 86 Sr)i of 0.7041-0.7064, ε (Nd) t of +2.5 - +5.7 and TDM age of 312-562 Ma, positive ε Nd, low ( 87 Sr/ 86 Sr)i ratio and young Nd model ages suggest relatively high contents of mantle-derived components in their sources, and this type granite might melt from subduction oceanic crust. The granites occurred intra-Gangdes block which were caused by collision of continent and post-collision, have ( 87 Sr/ 86 Sr)i of 0.706-0.719, ε (Nd) t of -5.3 - -8.3 and TDM age of 1323-1496 Ma, negative ε Nd, relative high ( 87 Sr/ 86 Sr)i ratio with an mid-Proterozoic Nd model ages, suggest granite has the mixing genesis of mantle-derived components and old crustal components in their sources. With relatively small variation range in ε (Nd) t and TDM age, it might imply granitic isotopic source in Gandes block to keep relative homogenization in long period. The granites in Himalayan block which there is not oceanic material to join in melting and to cause of intra-continental subduction, has most ( 87 Sr/ 86 Sr)i ratio more than 0.720, ε (Nd) t of -10.3 - -16.3 and TDM age of 1792-2206 Ma, high ( 87 Sr/ 86 Sr)i ratio, low negative ε (Nd)t with old Nd isotopic model ages and consistent with the Sr, Nd isotopic compositions of basement

  6. AutoAssemblyD: a graphical user interface system for several genome assemblers.

    Science.gov (United States)

    Veras, Adonney Allan de Oliveira; de Sá, Pablo Henrique Caracciolo Gomes; Azevedo, Vasco; Silva, Artur; Ramos, Rommel Thiago Jucá

    2013-01-01

    Next-generation sequencing technologies have increased the amount of biological data generated. Thus, bioinformatics has become important because new methods and algorithms are necessary to manipulate and process such data. However, certain challenges have emerged, such as genome assembly using short reads and high-throughput platforms. In this context, several algorithms have been developed, such as Velvet, Abyss, Euler-SR, Mira, Edna, Maq, SHRiMP, Newbler, ALLPATHS, Bowtie and BWA. However, most such assemblers do not have a graphical interface, which makes their use difficult for users without computing experience given the complexity of the assembler syntax. Thus, to make the operation of such assemblers accessible to users without a computing background, we developed AutoAssemblyD, which is a graphical tool for genome assembly submission and remote management by multiple assemblers through XML templates. AssemblyD is freely available at https://sourceforge.net/projects/autoassemblyd. It requires Sun jdk 6 or higher.

  7. Strain-Mediated Inverse Photoresistivity in SrRuO3/La0.7Sr0.3MnO3Superlattices

    KAUST Repository

    Liu, Heng-Jui

    2015-12-09

    © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. In the pursuit of novel functionalities by utilizing the lattice degree of freedom in complex oxide heterostructure, the control mechanism through direct strain manipulation across the interfaces is still under development, especially with various stimuli, such as electric field, magnetic field, light, etc. In this study, the superlattices consisting of colossal-magnetoresistive manganites La0.7Sr0.3MnO3 (LSMO) and photostrictive SrRuO3 (SRO) have been designed to investigate the light-dependent controllability of lattice order in the corresponding functionalities and rich interface physics. Two substrates, SrTiO3 (STO) and LaAlO3 (LAO), have been employed to provide the different strain environments to the superlattice system, in which the LSMO sublayers exhibit different orbital occupations. Subsequently, by introducing light, we can modulate the strain state and orbital preference of LSMO sublayers through light-induced expansion of SRO sublayers, leading to surprisingly opposite changes in photoresistivity. The observed photoresistivity decreases in the superlattice grown on STO substrate while increases in the superlattice grown on LAO substrate under light illumination. This work has presented a model system that demonstrates the manipulation of orbital-lattice coupling and the resultant functionalities in artificial oxide superlattices via light stimulus. A fascinating model system of optic-driven functionalities has been achieved by artificial superlattices consisting of manganite La0.7Sr0.3MnO3 (LSMO) and photostrictive SrRuO3 (SRO). With design of different initial strain and orbital states in superlattices, we can even control the photoresistivity of the superlattices in an opposite trend that cannot be achieved in pure single film.

  8. Politiques et dynamique des systèmes de production: comment concilier défi alimentaire, compétitivité et environnement ?

    OpenAIRE

    Chatellier, Vincent; Dupraz, Pierre

    2011-01-01

    Cette communication propose une réflexion portant sur l’influence des politiques publiques (commerciale, agricole et environnementale) sur la dynamique des systèmes de production en agriculture. Elle rappelle, dans un premier temps, que les politiques commerciales définies dans le cadre des accords de l’OMC contribuent à une libéralisation accentuée des marchés agricoles internationaux. En se focalisant sur les principales productions agricoles développées dans l’Union européenne (céréales, l...

  9. Pulsed laser deposition of epitaxial Sr(RuxSn1-x)O3 thin film electrodes and KNbO3/Sr(RuxSn1-x)O3 bilayers

    International Nuclear Information System (INIS)

    Christen, H.M.; Boatner, L.A.; English, L.Q.; Geea, L.A.; Marrero, P.J.; Norton, D.P.

    1995-01-01

    Sr(Ru x Sn 1-x ) 3 is proposed as a new conducting oxide for use in epitaxial multilayer structures. The Sr(Ru o 48 Sn 0.52 )0 3 composition exhibits an excellent lattice match with (100)-oriented KTaO 3 , and films of this composition grown by pulsed laser deposition on KTaO 3 , SrTiO 3 , and LaAlO 3 substrates have been analyzed by X-ray diffraction, Rutherford backscattering/ion channeling, and resistivity measurements. Epitaxial KNbO 3 /Sr(Ru 0.48 Sn 0.52 )O 3 bilayers have been successfully grown

  10. Etudes sur le mobilier Boulle, l'ébéniste de Louis XIV : quelques problèmes d'interfaces

    OpenAIRE

    Darque-Ceretti , Evelyne; Felder , Eric; Morini , Romain; Aucouturier , Marc; Paulin , Marc-André; Mathieu-Daudé , Agnès

    2010-01-01

    National audience; Dans le cadre d'un programme mis en place par le musée du Louvre, département des objets d'art, et le C2RMF, autour de l'étude et de la restauration des mobiliers attribués à l'atelier d'André-Charles Boulle ou à ses successeurs, il a été dégagé plusieurs problèmes concernant les marqueteries métalliques et les ornements en bronze doré. Cette communication traite en premier lieu de la compréhension de la mauvaise tenue au vieillissement des collages des pièces de marqueteri...

  11. Optimisation globale de problèmes Min-Max : Application à la synthèse de loi de commande robuste

    OpenAIRE

    Monnet , Dominique; Ninin , Jordan; Clement , Benoit

    2018-01-01

    International audience; Ces dernières années, la robotisation et l'automatisation des processus a eu une formidable croissance. Pour le grand public, le développement des drones aériens et des voitures auto-nomes a créé un véritable engouement pour les véhicules autonomes. L'utilisateur réclame de plus en plus que les systèmes d'aide à la décision, dans lesquels il devait intervenir, soient maintenant automatisés complètement, mais sans toutefois, dégrader la qualité du système ou sa sécurité...

  12. The temperature dependent strontium isotope fractionation (δ88/86Sr) during calcium carbonate precipitation

    International Nuclear Information System (INIS)

    Fietzke, J.; Eisenhauer, A.

    2006-01-01

    Full text: In order to study the influence of stable isotope fractionation during inorganic and biologically controlled CaCO 3 precipitation we have developed the analytical principles for the measurement of strontium (Sr) isotope fractionation. We have established a measurement protocol for the application on a MC-ICP-MS (AXIOM) using the common bracketing standard technique. The Sr-standard CRM NBS987 was used as reference material for all measurements and to calculate the Sr fractionation. Latter value is expressed by the δ-notation defined as: δ 88/86 Sr = [( 88 Sr/ 86 Sr)sample / ( 88 Sr/ 86 Sr)standard ] * 1000 -1. A first set of experiments focused on the temperature dependency of Sr-isotope fractionation. For this purpose inorganically precipitated aragonite and calcite was prepared under controlled conditions in a temperature range from 10 to 50 o C. In addition, cultured and naturally grown corals were analyzed for their δ 88/86 Sr values. Repeated measurements of IAPSO seawater standard showed a mean δ 88/86 Sr value of 0.383 ± 0.008 (2 SEM) being the isotopically heaviest material measured so far. The first results of the inorganically precipitated aragonite and the natural corals revealed a clear temperature dependency of the δ 88/86 Sr values. For inorganic aragonite the slope of this correlation is about 0.0055 permil/ o C. However, for naturally grown corals (Pavona clavus) a 6 fold steeper slope of 0.033 permil/ o C was determined. This strong temperature dependency implies the potential to use stable Sr isotopes as a new marine (paleo)temperature proxy. (author)

  13. Electronic structure of α-SrB4O7: experiment and theory

    International Nuclear Information System (INIS)

    Atuchin, V V; Kesler, V G; Zaitsev, A I; Molokeev, M S; Aleksandrovsky, A S; Kuzubov, A A; Ignatova, N Y

    2013-01-01

    The investigation of valence band structure and electronic parameters of constituent element core levels of α-SrB 4 O 7 has been carried out with x-ray photoemission spectroscopy. Optical-quality crystal α-SrB 4 O 7 has been grown by the Czochralski method. Detailed photoemission spectra of the element core levels have been recorded from the powder sample under excitation by nonmonochromatic Al Kα radiation (1486.6 eV). The band structure of α-SrB 4 O 7 has been calculated by ab initio methods and compared to XPS measurements. It has been found that the band structure of α-SrB 4 O 7 is weakly dependent on the Sr-related states. (paper)

  14. Magnetoelectric Response in Multiferroic SrFe12O19 Ceramics.

    Directory of Open Access Journals (Sweden)

    Guolong Tan

    Full Text Available We report here realization of ferroelectricity, ferromagnetism and magnetocapacitance effect in singleSrFe12O19ceramic at room temperature. The ceramics demonstrate a saturated polarization hysteresis loop, two nonlinear I-V peaks and large anomaly of dielectric constant near Curie temperature, which confirm the intrinsic ferroelectricity of SrFe12O19 ceramicswith subsequent heat-treatment in O2atmosphere. The remnant polarization of the SrFe12O19 ceramic is estimated to be 103μC/cm2. The ceramic also exhibits strong ferromagnetic characterization, the coercive field and remnant magnetic moment are 6192Oe and 35.8emu/g, respectively. Subsequent annealing SrFe12O19 ceramics in O2 plays a key role on revealing its intrinsic ferroelectricity and improving the ferromagnetism through transforming Fe2+ into Fe3+. By applying a magnetic field, the capacitance demonstrates remarkable change along with B field, the maximum rate of change in ε (Δε(B/ε(0 is 1174%, which reflects a giant magnetocapacitance effect in SrFe12O19. XPS and molecular magnetic moment measurements confirmed the transformation of Fe2+ into Fe3+ and removal of oxygen vacancies upon O2 heat treatment. These combined functional responses in SrFe12O19 ceramics opens substantial possibilities for applications in novel electric devices.

  15. The dehydration of SrTeO3(H2O)--a topotactic reaction for preparation of the new metastable strontium oxotellurate(IV) phase ε-SrTeO3.

    Science.gov (United States)

    Stöger, Berthold; Weil, Matthias; Baran, Enrique J; González-Baró, Ana C; Malo, Sylvie; Rueff, Jean Michel; Petit, Sebastien; Lepetit, Marie Bernadette; Raveau, Bernard; Barrier, Nicolas

    2011-05-28

    Microcrystalline single-phase strontium oxotellurate(IV) monohydrate, SrTeO(3)(H(2)O), was obtained by microwave-assisted hydrothermal synthesis under alkaline conditions at 180 °C for 30 min. A temperature of 220 °C and longer reaction times led to single crystal growth of this material. The crystal structure of SrTeO(3)(H(2)O) was determined from single crystal X-ray diffraction data: P2(1)/c, Z = 4, a = 7.7669(5), b = 7.1739(4), c = 8.3311(5) Å, β = 107.210(1)°, V = 443.42(5) Å(3), 1403 structure factors, 63 parameters, R[F(2)>2σ(F(2))] = 0.0208, wR(F(2) all) = 0.0516, S = 1.031. SrTeO(3)(H(2)O) is isotypic with the homologous BaTeO(3)(H(2)O) and is characterised by a layered assembly parallel to (100) of edge-sharing [SrO(6)(H(2)O)] polyhedra capped on each side of the layer by trigonal-prismatic [TeO(3)] units. The cohesion of the structure is accomplished by moderate O-H···O hydrogen bonding interactions between donor water molecules and acceptor O atoms of adjacent layers. In a topochemical reaction, SrTeO(3)(H(2)O) condensates above 150 °C to the metastable phase ε-SrTeO(3) and transforms upon further heating to δ-SrTeO(3). The crystal structure of ε-SrTeO(3), the fifth known polymorph of this composition, was determined from combined electron microscopy and laboratory X-ray powder diffraction studies: P2(1)/c, Z = 4, a = 6.7759(1), b = 7.2188(1), c = 8.6773(2) Å, β = 126.4980(7)°, V = 341.20(18) Å(3), R(Fobs) = 0.0166, R(Bobs) = 0.0318, Rwp = 0.0733, Goof = 1.38. The structure of ε-SrTeO(3) shows the same basic set-up as SrTeO(3)(H(2)O), but the layered arrangement of the hydrous phase transforms into a framework structure after elimination of water. The structural studies of SrTeO(3)(H(2)O) and ε-SrTeO(3) are complemented by thermal analysis and vibrational spectroscopic measurements.

  16. Determination of 90Sr in radioactive liquid waste-a comparative study using 'SrCO3 precipitation, extraction chromatography and Cerenkov radiation counting' techniques

    International Nuclear Information System (INIS)

    Mani, A.G.S.; Renganathan, K.; Rao, S.V.S.; Sinha, P.K.

    2007-01-01

    In the wastes generated at nuclear power plants, 90 Sr and 90 Y are responsible for approximately 7% and 38% of the total fission product activity after 1 year and 10 years respectively. Monitoring of the liquid waste produced in nuclear facilities for 90 Sr before and after releasing to the aquatic environment is essential, as it can cause a long term biological hazard due to its chemical similarity with Ca, high fission yield (5.9%) and long radioactive and biological half lives of 28 and 49.3 years respectively. As conventional carbonate precipitation method for 90 Sr- 90 Y estimation is laborious and time consuming, the other methods like extraction chromatography technique using strontium selective crown ether and Cerenkov radiation counting by liquid scintillation analyser (LSA) were also investigated. This paper describe procedures involved in the estimation of strontium in low-level radioactive liquid effluent by using above methods and deals with the comparison of results. Cerenkov radiation counting by LSA has an edge over the other methods in the determination of 90 Sr as it is a simple and rapid technique. Experiences gained in the estimation of 90 Sr in low-level radioactive liquid effluent using Cerenkov radiation counting technique is discussed in detail in this paper. (author)

  17. Environmental Assessment, SR 123 (Roger J. Clary Highway) from North of the Intersection of SR 123 and SR 85S to SR 85N, Okaloosa County, Eglin Air Force Base, Florida

    Science.gov (United States)

    2012-05-01

    mph) SRS 123 / SR 85 Traffic Volumes Receptor Max 1-Hr CO Conc (ppm) Max 8-Hr CO Conc (ppm) AADT VPH Alternative 2 (East Shift) and...8.4 5.0 AADT: Annual Average Daily Traffic. VPH : Vehicles per Hour Environmental Consequences Air Quality Impacts

  18. Crystal structures of KM(AsF{sub 6}){sub 3} (M{sup 2+} = Mg, Co, Mn, Zn), KCu(SbF{sub 6}){sub 3} and [Co(HF){sub 2}]Sr[Sr(HF)]{sub 2}-[Sr(HF){sub 2}]{sub 2}[AsF{sub 6}]{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Mazej, Zoran; Goreshnik, Evgeny [Jozef Stefan Institute, Ljubljana (Slovakia). Dept. of Inorganic Chemisrty and Technology

    2015-05-01

    The KM(AsF{sub 6}){sub 3} (M{sup 2+} = Mg, Co, Mn, Zn) and KCu(SbF{sub 6}){sub 3} compounds crystallize isotypically to previously known KNi(AsF{sub 6}){sub 3}. The main features of the structure of these compounds are rings of MF{sub 6} octahedra sharing apexes with AsF{sub 6} octahedra connected into infinite tri-dimensional frameworks. In this arrangement cavities are formed where K{sup +} cations are placed. Single crystals of CoSr{sub 5}(AsF{sub 6}){sub 12}.8HF were obtained as one of the products after the crystallization of 3KF/CoF{sub 2}/SrF{sub 2} mixture in the presence of AsF{sub 5} in anhydrous HF. The CoSr{sub 5}(AsF{sub 6}){sub 12}.8HF is monoclinic, C/2c (No.15), with a = 26.773(5) Aa, b = 10.087(2) Aa, c = 21.141(5) Aa, β = 93.296(13) {sup circle}, V = 5699.9(19) Aa{sup 3} at 200 K, and Z = 4. There are three crystallographically non-equivalent Sr{sup 2+} cations in the crystal structure of CoSr{sub 5}(AsF{sub 6}){sub 12}.8HF. The Sr1 is coordinated by ten fluorine atoms from eight different [AsF{sub 6}]- anions, meanwhile Sr2 and Sr3 are bound to nine fluorine atoms provided by one HF and eight AsF{sub 6} units or by two HF and six AsF{sub 6} units, respectively. The Co{sup 2+} is coordinated distorted-octahedrally by six fluorine atoms from two HF molecules and four different AsF{sub 6} units. All those moieties in the crystal structure of [Co(HF){sub 2}]Sr[Sr(HF)]{sub 2}[Sr(HF){sub 2}]{sub 2}[AsF{sub 6}]{sub 12} are connected into tridimensional framework. The CoSr{sub 5}(AsF{sub 6}){sub 12}.8HF is a unique example of compound where HF molecules are directly bound via fluorine atoms to two different metal centres.

  19. Ternary systems Sr-{Ni,Cu}-Si: Phase equilibria and crystal structure of ternary phases

    International Nuclear Information System (INIS)

    Nasir, Navida; Melnychenko-Koblyuk, Nataliya; Grytsiv, Andriy; Rogl, Peter; Giester, Gerald; Wosik, Jaroslaw; Nauer, Gerhard E.

    2010-01-01

    Phase relations were established in the Sr-poor part of the ternary systems Sr-Ni-Si (900 deg. C) and Sr-Cu-Si (800 deg. C) by light optical microscopy, electron probe microanalysis and X-ray diffraction on as cast and annealed alloys. Two new ternary compounds SrNiSi 3 (BaNiSn 3 -type) and SrNi 9-x Si 4+x (own-type) were found in the Sr-Ni-Si system along with previously reported Sr(Ni x Si 1-x ) 2 (AlB 2 -type). The crystal structure of SrNi 9-x Si 4+x (own-type, x=2.7, a=0.78998(3), c=1.1337(2) nm; space group P4/nbm) was determined from X-ray single crystal counter to be a low symmetry derivative of the cubic, parent NaZn 13 -type. At higher Si-content X-ray Rietveld refinements reveal the formation of a vacant site (□) corresponding to a formula SrNi 5.5 Si 6.5 □ 1.0 . Phase equilibria in the Sr-Cu-Si system are characterized by the compounds SrCu 2-x Si 2+x (ThCr 2 Si 2 -type), Sr(Cu x Si 1-x ) 2 (AlB 2 -type), SrCu 9-x Si 4+x (0≤x≤1.0; CeNi 8.5 Si 4.5 -type) and SrCu 13-x Si x (4≤x≤1.8; NaZn 13 -type). The latter two structure types appear within a continuous solid solution. Neither a type-I nor a type-IX clathrate compound was encountered in the Sr-{Cu,Ni}-Si systems. Structural details are furthermore given for about 14 new ternary compounds from related alloy systems with Ba. - Graphical abstract: The crystal structure of SrNi 9-x Si 4+x (own-type, x=2.7, a=0.78998(3), c=1.1337(2) nm; space group P4/nbm) was determined from X-ray single crystal counter to be a low symmetry derivative of the cubic, parent NaZn 13 -type and is related to CeNi 8.5 Si 4.5 -type.

  20. Determination of 90Sr in crude coconut oil by Cherenkov radiation measurement

    International Nuclear Information System (INIS)

    Santos, F.L.; Esguerra, L.V.; Castaneda, S.S.

    1991-01-01

    In December 1989, the Analytical Measurements Research group received crude coconut oil samples for radiometric determination of 90 Sr as required by the government of an importing country. The limit for 90 Sr in imported products was 67 BqKg -1 . The possibility of 90 Sr contamination of coconut oil is remote, considering that the molecular structures of its constituents do not include inorganic species. However, a method still had to be developed for certifying to the absence of 90 Sr in the samples. The technique selected was based on the direct measurement of 90 Sr/ 90 Y Cherenkov radiation in oil. For 10 ml of samples (approximately 9 g.) and a counting period of 1 hr. lower limits of detection ranging from 16 to 27 BqKg -1 were obtained. These detection limits, being well below the regulatory limit of 67 BqKg -1 for 90 Sr were adequate for purposes of the study. A total of ten crude coconut oil samples analyzed between December 1989 and June 1990 did not have detectable 90 Sr/ 90 Y activities. (auth.). 7 refs.; 1 fig

  1. Investigations of 90 SR activity concentrations in animal bones in Croatia

    Energy Technology Data Exchange (ETDEWEB)

    Maracic, M.; Franic, Z.; Marovic, G. [Institute for Medical Research and Occupational Health, Zagreb (Croatia)

    2006-07-01

    The paper describes investigations of 90 Sr activity concentrations in long bones of some domestic animals (cows, pigs and lambs) collected over the last ten years in the Republic of Croatia. These investigations are a part of an extended and still ongoing monitoring programme of radioactive contamination of human environment in Croatia. Bone is a critical organ for the accumulation of many radionuclides, including 90 Sr, a highly toxic radionuclide, similar to calcium in its chemicalaviour and metabolic processes. It has been found that the 90 Sr activity concentrations in bones differ between respective animal species, the highest activity concentrations being found in lamb bones. As the decrease of activity concentrations can be generally described by the exponential function, by fitting the measured data to the theoretical curve was estimated the ecological half-life of 90 Sr in bones of respective species. In addition was investigated the relation between 90 Sr activity concentrations in bones and fallout. The transient increases and decreases in 90 Sr activity concentrations in bones can be partially explained by a variety of environmental physical factors that naturally fluctuate. (authors)

  2. Investigations of 90 SR activity concentrations in animal bones in Croatia

    International Nuclear Information System (INIS)

    Maracic, M.; Franic, Z.; Marovic, G.

    2006-01-01

    The paper describes investigations of 90 Sr activity concentrations in long bones of some domestic animals (cows, pigs and lambs) collected over the last ten years in the Republic of Croatia. These investigations are a part of an extended and still ongoing monitoring programme of radioactive contamination of human environment in Croatia. Bone is a critical organ for the accumulation of many radionuclides, including 90 Sr, a highly toxic radionuclide, similar to calcium in its chemical behaviour and metabolic processes. It has been found that the 90 Sr activity concentrations in bones differ between respective animal species, the highest activity concentrations being found in lamb bones. As the decrease of activity concentrations can be generally described by the exponential function, by fitting the measured data to the theoretical curve was estimated the ecological half-life of 90 Sr in bones of respective species. In addition was investigated the relation between 90 Sr activity concentrations in bones and fallout. The transient increases and decreases in 90 Sr activity concentrations in bones can be partially explained by a variety of environmental physical factors that naturally fluctuate. (authors)

  3. Thermal expansion behaviour in the oxygen deficient perovskites Sr2BSbO5.5 (B=Ca, Sr, Ba). Competing effects of water and oxygen ordering

    International Nuclear Information System (INIS)

    Zhou Qingdi; Kennedy, Brendan J.; Avdeev, Maxim

    2011-01-01

    Neutron diffractions studies reveal the presence of oxygen disorder in the oxygen deficient perovskites Sr 2 BSbO 5.5 (B=Ca, Sr, Ba). Synchrotron X-ray studies demonstrate that these oxides have a double perovskite-type structure with the cell size increasing as the size of the B cation increases from 8.2114(2) A for B=Ca to 8.4408(1) A for B=Ba. It is postulated that a combination of local clustering of the anions and vacancies together with water-water and water-host hydrogen bonds plays a role in defining the volume of the encapsulated water clusters and that changes in the local structure upon heating result in anomalous thermal expansion observed in variable temperature diffraction measurements. - Graphical abstract: The oxides Sr 2 BSbO 5.5 (B=Ca, Sr, Ba) have unusual anion disorder. There is a lag in the contraction in the cell size of Sr 2 CaSbO 5.5 nH 2 O established from X-ray diffraction measurements following the loss of water suggesting changes on the local structure are important. Highlights: → The average structures of the defect perovskites Sr 2 MSbO 5.5 established. → Anion and cation disorder quantified by neutron and synchrotron X-ray diffraction. → Anomalous thermal expansion due to local clustering of anions and vacancies observed.

  4. High-Precision In Situ 87Sr/86Sr Analyses through Microsampling on Solid Samples: Applications to Earth and Life Sciences

    Directory of Open Access Journals (Sweden)

    Sara Di Salvo

    2018-01-01

    Full Text Available An analytical protocol for high-precision, in situ microscale isotopic investigations is presented here, which combines the use of a high-performing mechanical microsampling device and high-precision TIMS measurements on micro-Sr samples, allowing for excellent results both in accuracy and precision. The present paper is a detailed methodological description of the whole analytical procedure from sampling to elemental purification and Sr-isotope measurements. The method offers the potential to attain isotope data at the microscale on a wide range of solid materials with the use of minimally invasive sampling. In addition, we present three significant case studies for geological and life sciences, as examples of the various applications of microscale 87Sr/86Sr isotope ratios, concerning (i the pre-eruptive mechanisms triggering recent eruptions at Nisyros volcano (Greece, (ii the dynamics involved with the initial magma ascent during Eyjafjallajökull volcano’s (Iceland 2010 eruption, which are usually related to the precursory signals of the eruption, and (iii the environmental context of a MIS 3 cave bear, Ursus spelaeus. The studied cases show the robustness of the methods, which can be also be applied in other areas, such as cultural heritage, archaeology, petrology, and forensic sciences.

  5. Radiochemical separation and effective dose estimation due to ingestion of 90Sr

    International Nuclear Information System (INIS)

    Ilic, Z.; Vidic, A.; Deljkic, D.; Sirko, D.; Zovko, E.; Samek, D.

    2009-01-01

    Since 2007. Institute for Public Health of Federation of Bosnia and Herzegovina-Radiation Protection Centre, within the framework of monitoring of radioactivity of environment carried out measurement of specific activity of 90 Sr content in selected food and water samples. The paper described the methods of measurement and radiochemical separation. Presented results, as average values of specific activity of 90 Sr, were used for estimation of effective dose due to ingestion of 90 Sr for 2007. and 2008. Estimated effective dose for 2007. due to ingestion of 90 Sr for adults was 1,36 μSv and 2,03 μSv for children (10 year old), and for 2008. 0,67 μSv (adults) and 1,01 μSv (children 10 year old). Estimated effective doses for 2007. and 2008. are varied because of different average specific activity radionuclide 90 Sr in selected samples of food, their number, species and origin. (author) [sr

  6. Biological response of Sr-containing coating with various surface treatments on titanium substrate for medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Shih-Ping [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan (China); Lee, Tzer-Min, E-mail: tmlee@mail.ncku.edu.tw [Institute of Oral Medicine, National Cheng Kung University, Tainan, Taiwan (China); School of Dentistry, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Lui, Truan-Sheng [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan (China)

    2015-08-15

    Graphical abstract: - Highlights: • Sr-containing coating prepared by plasma spraying and micro-arc oxidation process, respectively. • MAO coating stimulated high ECM-like structures of cells on early stage. • Sr-containing specimens had high cell responses on late stage. • Sr-MAO coating is a desirable implant surface treatment for clinical applications. - Abstract: An implant requires a suitable surface to trigger osteointegration. The surface characteristics and chemical composition are important factors in this process. Plasma spraying and micro-arc oxidation can be used to fabricate rough and porous structures for medical applications. Strontium (Sr) has been shown to prevent osteoporosis in vitro and in vivo. However, few scientists have evaluated the biological response of Sr-containing coatings on different surface treatments. In this study, a sand-blasted (SB) surface (as the control), plasma-sprayed hydroxyapatite (HA) and Sr-substituted HA coatings (HAPS and SrHAPS, respectively), calcium phosphate and Sr-containing calcium phosphate micro-arc oxidation surface (CPM and SrCPM, respectively) were analyzed in terms of human osteoblastic cell (MG63) response. Sr was confirmed to be incorporated into the surface. SrHAPS and SrCPM specimens had higher cell responses than those of the HAPS and CPM groups, respectively. The cells cultured on SrCPM and SrHAPS specimens exhibited high proliferation and differentiation. However, CPM and SrCPM specimens stimulated more ECM-like structures than other specimens. The results show that Sr-containing coatings have good characteristics that enhance cell response. The SrCPM coating is a suitable implant surface treatment for clinical applications.

  7. Biological response of Sr-containing coating with various surface treatments on titanium substrate for medical applications

    International Nuclear Information System (INIS)

    Yang, Shih-Ping; Lee, Tzer-Min; Lui, Truan-Sheng

    2015-01-01

    Graphical abstract: - Highlights: • Sr-containing coating prepared by plasma spraying and micro-arc oxidation process, respectively. • MAO coating stimulated high ECM-like structures of cells on early stage. • Sr-containing specimens had high cell responses on late stage. • Sr-MAO coating is a desirable implant surface treatment for clinical applications. - Abstract: An implant requires a suitable surface to trigger osteointegration. The surface characteristics and chemical composition are important factors in this process. Plasma spraying and micro-arc oxidation can be used to fabricate rough and porous structures for medical applications. Strontium (Sr) has been shown to prevent osteoporosis in vitro and in vivo. However, few scientists have evaluated the biological response of Sr-containing coatings on different surface treatments. In this study, a sand-blasted (SB) surface (as the control), plasma-sprayed hydroxyapatite (HA) and Sr-substituted HA coatings (HAPS and SrHAPS, respectively), calcium phosphate and Sr-containing calcium phosphate micro-arc oxidation surface (CPM and SrCPM, respectively) were analyzed in terms of human osteoblastic cell (MG63) response. Sr was confirmed to be incorporated into the surface. SrHAPS and SrCPM specimens had higher cell responses than those of the HAPS and CPM groups, respectively. The cells cultured on SrCPM and SrHAPS specimens exhibited high proliferation and differentiation. However, CPM and SrCPM specimens stimulated more ECM-like structures than other specimens. The results show that Sr-containing coatings have good characteristics that enhance cell response. The SrCPM coating is a suitable implant surface treatment for clinical applications

  8. μSR spectroscopy on free radicals: a complement to ESR spectroscopy

    International Nuclear Information System (INIS)

    Cox, S.F.J.; Symons, M.C.R.

    1986-12-01

    The paper on ''μSR spectroscopy on free radicals'' was presented to the conference on ''Muon spin, rotation, relaxation and resonance'' Uppsala, 1986. The spectroscopic techniques for both ESR and μSR are described, along with the interpretation of the spectra, hyperfine coupling constants and radical structure. A comparison of ESR and μSR data is carried out with respect: to 1) isotope effects in organic radicals, 2) isotope effects in solids, -the isotropic muonium defect centres, and 3) the muonium defect centres in semiconductors. Radical categories examined using ESR and μSR are discussed, including new species, formation mechanisms, and ionic species. (U.K.)

  9. A novel UV-emitting phosphor: LiSr4(BO3)3: Pb2+

    International Nuclear Information System (INIS)

    Pekgözlü, İlhan

    2013-01-01

    Pure and Pb 2+ doped LiSr 4 (BO 3 ) 3 materials were prepared by a solution combustion synthesis method. The phase analysis of all synthesized materials were determined using the powder XRD. The synthesized materials were investigated using spectrofluorometer at room temperature. The excitation and emission bands of LiSr 4 (BO 3 ) 3 : Pb 2+ were observed at 284 and 328 nm, respectively. The dependence of the emission intensity on the Pb 2+ concentration for the LiSr 4 (BO 3 ) 3 were studied in detail. It was observed that the concentration quenching of Pb 2+ in LiSr 4 (BO 3 ) 3 is 0.005 mol. The Stokes shifts of LiSr 4 (BO 3 ) 3 : Pb 2+ phosphor was calculated to be 4723 cm –1 . -- Highlights: • A novel UV-emitting phosphor: LiSr 4 (BO 3 ) 3 : Pb 2+ ” synthesized for the first time. • The emission band of LiSr 4 (BO 3 ) 3 : Pb 2+ was observed at 328 nm upon excitation with 284 nm. • LiSr 4 (BO 3 ) 3 : Pb 2+ is a good phosphor for broadband UV application

  10. Transportin-SR is required for proper splicing of resistance genes and plant immunity.

    Directory of Open Access Journals (Sweden)

    Shaohua Xu

    2011-06-01

    Full Text Available Transportin-SR (TRN-SR is a member of the importin-β super-family that functions as the nuclear import receptor for serine-arginine rich (SR proteins, which play diverse roles in RNA metabolism. Here we report the identification and cloning of mos14 (modifier of snc1-1, 14, a mutation that suppresses the immune responses conditioned by the auto-activated Resistance (R protein snc1 (suppressor of npr1-1, constitutive 1. MOS14 encodes a nuclear protein with high similarity to previously characterized TRN-SR proteins in animals. Yeast two-hybrid assays showed that MOS14 interacts with AtRAN1 via its N-terminus and SR proteins via its C-terminus. In mos14-1, localization of several SR proteins to the nucleus was impaired, confirming that MOS14 functions as a TRN-SR. The mos14-1 mutation results in altered splicing patterns of SNC1 and another R gene RPS4 and compromised resistance mediated by snc1 and RPS4, suggesting that nuclear import of SR proteins by MOS14 is required for proper splicing of these two R genes and is important for their functions in plant immunity.

  11. Impact des changements climatiques sur les écosystèmes alpins : comment les mettre en évidence et les prévoir ?

    Directory of Open Access Journals (Sweden)

    Nigel G. Yoccoz

    2011-01-01

    Full Text Available Les écosystèmes alpins vont être grandement influencés par les changements climatiques à venir, mais d’autres facteurs, tels que l’utilisation des terres ou les espèces invasives, pourront aussi jouer un rôle important. Le climat peut influencer les écosystèmes à différents niveaux, et nous en décrivons certains, en mettant l’accent sur les méthodes utilisées et les données disponibles. Le climat peut d’abord modifier la phénologie des espèces, comme la date de floraison des plantes ou la date d’éclosion des insectes. Il peut ensuite affecter directement la démographie des espèces (survie, reproduction, dispersion et donc à terme leur répartition. Il peut enfin agir sur les interactions entre espèces – le couvert neigeux par exemple modifie le succès de certains prédateurs. Une caractéristique des écosystèmes alpins est la présence d’un manteau neigeux important et pourtant l’influence de la neige reste relativement mal connue, en particulier pour des raisons logistiques. Même si nous avons fait des progrès importants dans le développement de modèles prédictifs, surtout pour ce qui est de la répartition des plantes alpines, il reste à mettre en place des réseaux d’observations et d’expériences permettant de mieux tenir compte de la variabilité des écosystèmes alpins et des interactions avec le climat.Alpine ecosystems will be greatly impacted by climatic change, but other factors, such as land use and invasive species, are likely to play an important role too. Climate can influence ecosystems at several levels. We describe some of them, stressing methodological approaches and available data. Climate can modify species phenology, such as flowering date of plants and hatching date in insects. It can also change directly population demography (survival, reproduction, dispersal, and therefore species distribution. Finally it can effect interactions among species –snow cover for example

  12. 87Sr/86Sr isotope ratio analysis by laser ablation MC-ICP-MS in scales, spines, and fin rays as a nonlethal alternative to otoliths for reconstructing fish life history

    Science.gov (United States)

    Willmes, Malte; Glessner, Justin J. G.; Carleton, Scott A.; Gerrity, Paul C.; Hobbs, James A.

    2016-01-01

    Strontium isotope ratios (87Sr/86Sr) in otoliths are a well-established tool to determine origins and movement patterns of fish. However, otolith extraction requires sacrificing fish, and when working with protected or endangered species, the use of nonlethal samples such as scales, spines, and fin rays is preferred. Unlike otoliths that are predominantly aragonite, these tissues are composed of biological apatite. Laser ablation multicollector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) analysis of biological apatite can induce significant interference on mass 87, causing inaccurate 87Sr/86Sr measurements. To quantify this interference, we applied LA-MC-ICP-MS to three marine samples (white seabass (Atractoscion nobilis) otolith; green sturgeon (Acipenser medirostris) pectoral fin ray; salmon shark (Lamna ditropis) tooth), and freshwater walleye (Sander vitreus) otoliths, scales, and spines). Instrument conditions that maximize signal intensity resulted in elevated 87Sr/86Sr isotope ratios in the bioapatite samples, related to a polyatomic interference (40Ca31P16O, 40Ar31P16O). Retuning instrument conditions to reduce oxide levels removed this interference, resulting in accurate 87Sr/86Sr ratios across all tissue samples. This method provides a novel, nonlethal alternative to otolith analysis to reconstruct fish life histories.

  13. Conséquences écologiques des introductions dans les hydrosystèmes : essai de synthèse

    Directory of Open Access Journals (Sweden)

    HAURY J.

    1997-01-01

    Full Text Available Un essai de bilan des effets écologiques des introductions d'espèces est présenté à partir des exposés des orateurs de ce colloque et de la bibliographie. L'aspect inéluctable de la dispersion des espèces au cours du temps et l'efficacité toute relative des barrières intracontinentales qui s'y opposent sont soulignés. Les mécanismes en cause - vagilité et fécondité des espèces introduites, efficacité des barrières, structure des réseaux trophiques récepteurs, degré de saturation de leurs niches écologiques - sont étudiés en regard du fonctionnement des hydrosystèmes, montrant la complexité du problème. Des effets écologiques très variés sont décrits, dont beaucoup sont non intentionnels et inattendus ; un exemple bibliographique est développé, mettant en évidence la diversité des effets de la même introduction selon le milieu récepteur. Il en ressort la nécessité préliminaire absolue d'examiner à la fois la biologie des espèces à introduire et le fonctionnement de l'écosystème récepteur. Un principe de précaution est préconisé face à toute introduction volontaire, et une réglementation sévère et efficace face aux introductions involontaires. Le besoin d'une permanence d'agents de terrain pour établir une veille écologique est souligné. Face au manque de données objectives, des recherches scientifiques sur les effets écologiques des introductions passées ou possibles doivent être initiées ou poursuivies dans un cadre écosystémique, impliquant au minimum un suivi des écosystèmes risquant d'être colonisés.

  14. The Rb-Sr system

    International Nuclear Information System (INIS)

    Graham, I.J.

    1983-11-01

    This manual is intended to serve as a guide to the chemical procedures involved in Rb-Sr isotopic analysis as conducted at the Institute of Nuclear Sciences. Included are notes on the experimental developments made over the last 2.5 years, especially those involving rock dissolution and cation exchange chromatography

  15. The age of Male Karpaty Mts. granitoid rocks determined by Rb-Sr isochrone method

    International Nuclear Information System (INIS)

    Badgasaryan, G.P.; Gukasyan, R.Kh.; Veselsky, J.

    1982-01-01

    The results are presented of nuclear geochronological datings of Male Karpaty Mts. granitoids by Rb-Sr isochrone method. Using the method the age of Bratislava massif granitoids was established to be 347+-4 mil. y. at ( 87 Sr/ 86 Sr)=0.7076+-0.0013 and the age of Modra massif granitoids to be 324+-18 mil. y. at ( 87 Sr/ 86 Sr)=0.7075+-0.00032 (2σ). The relative agreement of age of both massifs as well as the agreement of the primary ratio ( 87 Sr/ 86 Sr) 0 not only testifies to their continuity in age but also in genesis. The same relations also confirm the genetic dependence of pegmatites and leucocratic granitoids on fundamental types of granitoids building up the Bratislava and Modra massifs. (author)

  16. Mécanique fondements et applications : avec 300 exercices et problèmes résolus

    CERN Document Server

    Pérez, José-Philippe

    1997-01-01

    Cet ouvrage fait partie de ceux que l'on acquiert dès le début de ses études et que l'on conserve comme ouvrage de référence. Ce cours rassemble en un seul volume les notions fondamentales de la mécanique. Il est construit en 32 chapitres volontairement assez courts mais très pédagogiques, illustrés d'environ 300 exercices et problèmes corrigés. La première partie concerne la mécanique du point matériel soumis à des forces. La seconde présente la mécanique des N points matériels en interaction. La troisième, plus technique, développe la mécanique générale des solides indéformables. Enfin la quatrième porte sur les bases de la mécanique des fluides.

  17. SR-BI: Linking Cholesterol and Lipoprotein Metabolism with Breast and Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Jorge L. Gutierrez-Pajares

    2016-10-01

    Full Text Available Studies have demonstrated the significant role of cholesterol and lipoprotein metabolism in the progression of cancer. The SCARB1 gene encodes the scavenger receptor class B type I (SR-BI, which is an 82-kDa glycoprotein with two transmembrane domains separated by a large extracellular loop. SR-BI plays an important role in the regulation of cholesterol exchange between cells and high-density lipoproteins. Accordingly, hepatic SR-BI has been shown to play an essential role in the regulation of the reverse cholesterol transport pathway, which promotes the removal and excretion of excess body cholesterol. In the context of atherosclerosis, SR-BI has been implicated in the regulation of intracellular signaling, lipid accumulation, foam cell formation, and cellular apoptosis. Furthermore, since lipid metabolism is a relevant target for cancer treatment, recent studies have focused on examining the role of SR-BI in this pathology. While signaling pathways have initially been explored in non-tumoral cells, studies with cancer cells have now demonstrated SR-BI’s function in tumor progression. In this review, we will discuss the role of SR-BI during tumor development and malignant progression. In addition, we will provide insights into the transcriptional and post-transcriptional regulation of the SCARB1 gene. Overall, studying the role of SR-BI in tumor development and progression should allow us to gain useful information for the development of new therapeutic strategies.

  18. Le transport aérien en Colombie. Historique et problèmes actuels

    Directory of Open Access Journals (Sweden)

    1993-01-01

    Full Text Available Le transport aérien colombien est à un tournant de son histoire. En effet, après une longue période de protectionnisme, l’État a décidé d’appliquer une politique libérale qui doit profondément modifier le ciel colombien. Cet article présente un historique de l’aviation nationale avant de s’attacher aux problèmes actuels. EL TRANSPORTE AÉREO EN COLOMBIA - HISTORIAL Y PROBLEMAS ACTUALES. El transporte aéreo se encuentra en un momento crucial de su historia. Después de un largo tiempo de proteccionismo, el Estado decidió autorizar una política liberal que debe modificar totalmente el cielo colombiano. Este artículo presenta una historia de la aviación nacional y analiza los problemas actuales. AERIAL TRANSPORT IN COLOMBIA - HISTORIC AND CURRENT PROBLEMS. Aerial transport in Colombia has entered a key period. After decades of protectionism, the State has initiated a liberal policy that will bring about a revolution in the Colombian skies. This article presents the history of national aviation and analyses its current problems.

  19. Study on the adsorption property of stable element Sr in loess

    International Nuclear Information System (INIS)

    Guo Qian; Wang Zhiming; Jiao Zhilan; Meng Liping; Guo Zhiming

    1999-01-01

    This paper described the adsorption property of Sr in the system of loess and groundwater. The absorption experiment method and the calculation formula for determining distribution coefficient of Sr in the system are presented in view of there being a considerable amount of background Sr in the system. It is ascertained that only a small amount of background Sr in loess takers part in absorption equilibrium. Apparent distribution coefficients Kd was determined at different equilibrium concentrations levels. When the solution-to-solid radio is 10:1, the Kd values is 53.7. Moreover, the determination of absorption isothermal curve shows that Sr absorption on loess is linear. The calculated value of distribution coefficients on the basis the curve and that of apparent distribution coefficient Kd are in good agreement. And also the effect of solution-to-solid ratio upon distribution coefficient was determined, indicating that Kd value significantly decreases with decrease of solution-to-solid ratio

  20. Avifauna del bosque mesófilo de montaña del noreste de Hidalgo, México Avifauna of the tropical montane cloud forest of northeastern Hidalgo, Mexico

    Directory of Open Access Journals (Sweden)

    Miguel Angel Martínez-Morales

    2007-06-01

    Full Text Available Este trabajo presenta los resultados de un inventario avifaunístico realizado de 1997 a 1999 en fragmentos de bosque mesófilo de montaña del noreste de Hidalgo, México. Se registraron 41 familias y 181 especies de aves mediante observaciones visuales y auditivas en 2 057 puntos de conteo, lo que representó el 98% de las especies esperadas en el área de estudio, para el período y método de muestreo utilizado. Se detectaron 16 especies restringidas al bosque mesófilo, 11 endémicas de México y 3 de distribución restringida. Adicionalmente, con base en la legislación mexicana vigente, 28 de las especies registradas están incluidas dentro de alguna categoría de riesgo de conservación. Esta comunidad de aves estuvo dominada por especies de aves pequeñas, raras (poco abundantes y residentes. Es probable que las más vulnerables de sufrir extinciones locales sean las especies raras y restringidas al bosque mesófilo, donde están incluidas las 3 especies de distribución restringida (Dendrortyx barbatus, Glaucidium sanchezi y Cyanolyca nana. La avifauna del bosque mesófilo de esta región incluye al 40% de la avifauna estatal, lo que destaca la relevancia de este tipo de vegetación y una urgente necesidad de establecer estrategias de manejo para su conservación.This study shows the results of bird census carried out from 1997 to 1999 in cloud forest fragments of northeastern Hidalgo, Mexico. Forty-one bird families and 181 species were recorded through visual and acoustic detections in 2 057 point counts. This represents 98% of the expected species richness for the sampling period and method used. Sixteen species restricted to the cloud forest were detected, 11 Mexican endemic species, and 3 restricted-range species were recorded. Additionally, 28 species are included within some category of conservation concern according to the present Mexican legislation. This bird community was dominated by small, rare (low in abundance, and

  1. PROPUESTA DE UN MODELO DE GESTION HUMANA Y CULTURA ORGANIZACIONAL PARA PyMES INNOVADORAS

    Directory of Open Access Journals (Sweden)

    RAFAEL IGNACIO PEREZ URIBE

    2003-07-01

    Full Text Available La gestión humana y cultura organizacional son conceptos inseparables en cualquier tipo de organización y han sido tratados extensamente en el ámbito académico general, pero no en el caso de las PyMES. Las condiciones sociales, económicas y culturales de este nuevo siglo hacen imprescindible que las empresas medianas y pequeñas sean altamente creativas, innovadoras, se adapten ágilmente a los cambios, sobrevivan y crezcan, y para lograrlo necesariamente deben contar con una fuerza laboral comprometida, capacitada y motivada, que trabaje en busca del logro de la misión de la organización, pero que a la vez sienta que están logrando satisfacer sus deseos, expectativas y necesidades más profundas. En este artículo se revisan algunos planteamientos que profundizan sobre gestión humana y cultura organizacional de manera integral y que sirven de guía básica temática para el diseño de un modelo de gestión humana.

  2. La gestion des ressources renouvelables: vers un gestion patrimoniale des écosystèmes

    Directory of Open Access Journals (Sweden)

    2004-01-01

    Full Text Available Cet article analyse et critique les approches de gestion biologique et économique des ressources naturelles traditionnellement appliquées. Sont présentées des alternatives à ces modèles, basées sur l’institutionnalisme et l’approche de gestion patrimoniale. Ce cadre théorique devrait favoriser la mise en œuvre d’une gestion viable des écosystèmes. Este artículo analiza y critica los modelos de gestión biológica y económica de recursos naturales tradicionalmente aplicados. Se presentan alternativas a estos modelos, basados en el institucionalismo y el manejo patrimonial, los que constituirían un marco teórico que viabilice la gestión de recursos naturales en los ecosistemas. This paper analyses and criticizes traditional approaches to biological and economic management of natural resources. Alternative approaches are presented based on institutionalism and heritage management these constitute a theoretical framework for the implementation of appropriate natural resource use in ecosystems.

  3. Cellular uptake and radiosensitization of SR-2508 loaded PLGA nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Jin Cheng [Fourth Military Medical University, Department of Radiation Medicine (China); Bai Ling [Xi' an Gaoxin Hospital, Department of Clinical Laboratories (China); Wu Hong [Fourth Military Medical University, Department of Pharmacy (China); Teng Zenghui [Fourth Military Medical University, Department of Pharmacology (China); Guo Guozhen, E-mail: guozhengg@tom.co [Fourth Military Medical University, Department of Radiation Medicine (China); Chen Jingyuan, E-mail: jy_chen@fmmu.edu.c [Fourth Military Medical University, Department of Occupational and Environmental Health (China)

    2008-08-15

    SR-2508 (etanidazole), a hypoxic radiosensitizer, has potential applications in radiotherapy. The poly(d,l-lactide-co-glycolide)(PLGA) nanoparticles containing SR-2508 were prepared by w/o/w emulsification-solvent evaporation method. The physicochemical characteristics of the nanoparticles (i.e. encapsulation efficiency, particle size distribution, morphology, in vitro release) were studied. The cellular uptake of the nanoparticles for the two human tumor cell lines: human breast carcinoma cells (MCF-7) and human carcinoma cervices cells (HeLa), was evaluated by fluorescence microscopy and transmission electronic microscopy. Cell viability was measured by the ability of single cell to form colonies in vitro. The prepared nanoparticles were spherical in shape with size between 90 nm and 190 nm. The encapsulation efficiency was 20.06%. The drug release pattern exhibited an initial burst followed by a plateau for over 24 h. The cellular uptake of nanoparticles was observed. Co-culture of MCF-7 and HeLa cells with SR-2508 loaded nanoparticles showed that released SR-2508 retained its bioactivity and effectively sensitized two hypoxic tumor cell lines to radiation. The radiosensitization of SR-2508 loaded nanoparticles was more significant than that of free drug.

  4. Cellular uptake and radiosensitization of SR-2508 loaded PLGA nanoparticles

    International Nuclear Information System (INIS)

    Jin Cheng; Bai Ling; Wu Hong; Teng Zenghui; Guo Guozhen; Chen Jingyuan

    2008-01-01

    SR-2508 (etanidazole), a hypoxic radiosensitizer, has potential applications in radiotherapy. The poly(d,l-lactide-co-glycolide)(PLGA) nanoparticles containing SR-2508 were prepared by w/o/w emulsification-solvent evaporation method. The physicochemical characteristics of the nanoparticles (i.e. encapsulation efficiency, particle size distribution, morphology, in vitro release) were studied. The cellular uptake of the nanoparticles for the two human tumor cell lines: human breast carcinoma cells (MCF-7) and human carcinoma cervices cells (HeLa), was evaluated by fluorescence microscopy and transmission electronic microscopy. Cell viability was measured by the ability of single cell to form colonies in vitro. The prepared nanoparticles were spherical in shape with size between 90 nm and 190 nm. The encapsulation efficiency was 20.06%. The drug release pattern exhibited an initial burst followed by a plateau for over 24 h. The cellular uptake of nanoparticles was observed. Co-culture of MCF-7 and HeLa cells with SR-2508 loaded nanoparticles showed that released SR-2508 retained its bioactivity and effectively sensitized two hypoxic tumor cell lines to radiation. The radiosensitization of SR-2508 loaded nanoparticles was more significant than that of free drug.

  5. Syntheses, crystal structures, NMR spectroscopy, and vibrational spectroscopy of Sr(PO{sub 3}F).H{sub 2}O and Sr(PO{sub 3}F)

    Energy Technology Data Exchange (ETDEWEB)

    Jantz, Stephan G.; Hoeppe, Henning A. [Lehrstuhl fuer Festkoerperchemie, Institut fuer Physik, Universitaet Augsburg (Germany); Wuellen, Leo van; Fischer, Andreas [Lehrstuhl fuer Chemische Physik und Materialwissenschaften, Institut fuer Physik, Universitaet Augsburg (Germany); Libowitzky, Eugen [Institute for Mineralogy and Crystallography, Faculty of Geosciences, Geography and Astronomy, University of Vienna (Austria); Baran, Enrique J. [Centro de Quimica Inorganica (CEQUINOR/CONICET, UNLP), Facultad de Ciencias Exactas, Universidad Nacional de La Plata (Argentina); Weil, Matthias [Institute for Chemical Technologies and Analytics, Division Structural Chemistry, Vienna University of Technology (Austria)

    2016-03-15

    Single crystals of Sr(PO{sub 3}F).H{sub 2}O {P2_1/c, Z = 4, a = 7.4844(2) Aa, b = 7.0793(2) Aa, c = 8.4265(2) Aa, β = 108.696(1) , V = 422.91(2) Aa"3, 2391 F_o"2, 70 parameters, R_1[F"2 > 2σ(F"2)] = 0.036; wR_2(F"2 all) = 0.049, S = 1.054} were grown from an aqueous solution by a metathesis reaction. The structure comprises [SrO{sub 8}] polyhedra and PO{sub 3}F tetrahedra that form a layered arrangement parallel to (100). The topotactic dehydration of this phase proceeds between 80 and 140 C to afford Sr(PO{sub 3}F). The monazite-type crystal structure of Sr(PO{sub 3}F) was elucidated from the X-ray powder data by simulated annealing [P2{sub 1}/c, Z = 4, a = 6.71689(9) Aa, b = 7.11774(11) Aa, c = 8.66997(13) Aa, β = 128.0063(7) , V = 326.605(8) Aa{sup 3}, R{sub p} = 0.010, R{sub wp} = 0.015, R{sub F} = 0.030]. During dehydration, the structure of Sr(PO{sub 3}F) .H{sub 2}O collapses along [100] from a layered arrangement into a framework structure, accompanied by a change of the coordination number of the Sr{sup 2+} ions from eight to nine. The magic-angle spinning (MAS) NMR and vibrational spectroscopy data of both phases are discussed. (Copyright copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Gibbs energy formation of Sr5Nb4O15

    International Nuclear Information System (INIS)

    Samui, Pradeep; Padhi, Anyuna; Agarwal, Renu; Kulkarni, S.G.

    2012-01-01

    Ternary oxides of strontium and niobium may form as fission product compounds in an operating nuclear reactor with oxide fuels under certain oxygen potential. Evaluations of thermodynamic stability of these ternary oxides are therefore important for assessment of fission product interactions. Furthermore, thermodynamic data of these oxides are also of relevance because of computation of phase diagram and phase stability of pseudo-ternary systems BaO-SrO-Nb 2 O 5 , SrO-Nb 2 O 5 -TaO 5 etc. in which some of the compounds are potential candidate materials for microwave ceramics with high dielectric constant, electro-optic, pyroelectric and piezoelectric devices. The system Sr-Nb-O contains many ternary oxides out of which we have investigated the thermodynamic parameters for the compound Sr 5 Nb 4 O 15 in the present study

  7. Long lasting yellow phosphorescence and photostimulated luminescence in Sr3SiO5 : Eu2+ and Sr3SiO5 : Eu2+, Dy3+ phosphors

    International Nuclear Information System (INIS)

    Sun Xiaoyuan; Zhang Jiahua; Zhang Xia; Luo Yongshi; Wang Xiaojun

    2008-01-01

    We report the observation of long lasting yellow phosphorescence and photostimulated luminescence (PSL) in Sr 3 SiO 5 : Eu 2+ and Sr 3 SiO 5 : Eu 2+ , Dy 3+ phosphors. The decay patterns of phosphorescence and thermoluminescence curves demonstrate that introduction of Dy 3+ into Sr 3 SiO 5 : Eu 2+ can generate a large number of shallow traps and deep traps. The generated deep traps prolong the phosphorescence up to 6 h after UV irradiation. The PSL is studied under 808 nm excitation. Slow rising and falling edges of the emission in Sr 3 SiO 5 : Eu 2+ , Dy 3+ are observed, showing a retrapping process by the generated shallow traps due to co-doping Dy 3+ .

  8. Sr isotope tracing of multiple water sources in a complex river system, Noteć River, central Poland

    Energy Technology Data Exchange (ETDEWEB)

    Zieliński, Mateusz, E-mail: mateusz.zielinski@amu.edu.pl [Institute of Geoecology and Geoinformation, Adam Mickiewicz University, Dzięgielowa 27, 61-680 Poznań (Poland); Dopieralska, Jolanta, E-mail: dopieralska@amu.edu.pl [Poznań Science and Technology Park, Adam Mickiewicz University Foundation, Rubież 46, 61-612 Poznań (Poland); Belka, Zdzislaw, E-mail: zbelka@amu.edu.pl [Isotope Laboratory, Adam Mickiewicz University, Dzięgielowa 27, 61-680 Poznań (Poland); Walczak, Aleksandra, E-mail: awalczak@amu.edu.pl [Isotope Laboratory, Adam Mickiewicz University, Dzięgielowa 27, 61-680 Poznań (Poland); Siepak, Marcin, E-mail: siep@amu.edu.pl [Institute of Geology, Adam Mickiewicz University, Maków Polnych 16, 61-606 Poznań (Poland); Jakubowicz, Michal, E-mail: mjakub@amu.edu.pl [Institute of Geoecology and Geoinformation, Adam Mickiewicz University, Dzięgielowa 27, 61-680 Poznań (Poland)

    2016-04-01

    Anthropogenic impact on surface waters and other elements in the environment was investigated in the Noteć River basin in central Poland. The approach was to trace changes in the Sr isotope composition ({sup 87}Sr/{sup 86}Sr) and concentration in space and time. Systematic sampling of the river water shows a very wide range of {sup 87}Sr/{sup 86}Sr ratios, from 0.7089 to 0.7127. This strong variation, however, is restricted to the upper course of the river, whereas the water in the lower course typically shows {sup 87}Sr/{sup 86}Sr values around 0.7104–0.7105. Variations in {sup 87}Sr/{sup 86}Sr are associated with a wide range of Sr concentrations, from 0.14 to 1.32 mg/L. We find that strong variations in {sup 87}Sr/{sup 86}Sr and Sr concentrations can be accounted for by mixing of two end-members: 1) atmospheric waters charged with Sr from the near-surface weathering and wash-out of Quaternary glaciogenic deposits, and 2) waters introduced into the river from an open pit lignite mine. The first reservoir is characterized by a low Sr content and high {sup 87}Sr/{sup 86}Sr ratios, whereas mine waters display opposite characteristics. Anthropogenic pollution is also induced by extensive use of fertilizers which constitute the third source of Sr in the environment. The study has an important implication for future archeological studies in the region. It shows that the present-day Sr isotope signatures of river water, flora and fauna cannot be used unambiguously to determine the “baseline” for bioavailable {sup 87}Sr/{sup 86}Sr in the past. - Highlights: • Sr isotopes fingerprint water sources and their interactions in a complex river system. • Mine waters and fertilizers are critical anthropogenic additions in the river water. • Limited usage of environmental isotopic data in archeological studies. • Sr budget of the river is dynamic and temporary.

  9. Rb-Sr geochronology of the rocks of the Himalayas, Eastern Nepal, (1)

    International Nuclear Information System (INIS)

    Kai, Kunio

    1981-01-01

    Rb-Sr isotopic measurements were carried out for whole rock and small sliced rock from the Himalayan gneiss which constitutes the metamorphosed basement of the Tethyan sediments. The results of the measurements on whole rock from the Barun migmatite, the Barun gneiss and the Irkhua gneiss indicate that complete Sr isotopic redistribution occurred about 520 m.y. ago. This age is interpreted as the time of the regional metamorphism. The analytical results of the small sliced slabs of the Himalayan gneiss indicate that Sr isotopic redistribution occurred among the sliced slabs 33.3 +- 13.2 m.y. ago. This age is interpreted as the time of the metamorphism in the sillimanite-amphibolite facies. The high initial 87 Sr/ 86 Sr ratio of 0.7372 +- 0.0031 from the Barun migmatite of the Himalayan gneiss suggests the Precambrian Origin of the source rocks. The analytical results on the sliced slab of the Barun migmatite indicate that the original age of the rocks is about 800 m.y. The rock is interpreted as the remobilized Precambrian crustal rock. The high initial 87 Sr/ 86 Sr ratio of the Barun gneiss and the Irkhua gneiss of the Himalayan gneiss (0.7234 +- 0.0013) indicates also the Precambrian origin of the source rocks. (author)

  10. Constraints on Ca/Sr as a Proxy for Calcium in Forest Ecosystems

    Science.gov (United States)

    Hoff, C. J.; Hobbie, E. A.; Hallett, R.; Colpaert, J.; Bryce, J. G.

    2004-05-01

    Calcium is a key plant nutrient and important base cation in ecosystems. Our current efforts to quantify Ca cycling in ecosystems rely on indirect proxies, e.g., Ca/Sr or Sr isotopic systems (1). An important assumption in these applications is that the elemental ratio of calcium to strontium faithfully represents calcium cycling and that little fractionation occurs through biogeochemical and physiological processes. However, several researchers have reported variations in Ca/Sr, e.g. among different tree tissues (2) and during weathering processes (3), raising doubts about the suitability of the proxy. To address the question of reliability, we measured Ca/Sr values in a culture study in which Scots pines were grown at low or high nutrient supply rates (3% per day or 5% per day). Because mycorrhizal fungi are intimately involved in plant nutrient supply, plants were also grown either uncolonized or colonized with one of two different species of mycorrhizal fungi (Suillus luteus and Thelephora terrestris). Our preliminary results indicate that Ca/Sr values differ between high and low nutrient treatments, root and foliage, and mycorrhizal treatments. In individual seedlings, roots have lower Ca/Sr than foliage by absolute factors of 2-5. The magnitude of the effect is apparently determined by a combination of environmental factors including both the nutrient and mycorrhizal treatments. These results indicate that Ca and Sr are partitioned differently between nutrient and mycorrhizal treatments and between plant fractions despite the common nutrient broth and substrate. Thus, Ca/Sr values alone are not reliable tracers of Ca within an ecosystem because of partitioning of Ca and Sr during nutrient transport within the plant-mycorrhizal system. We are presently refining analytical techniques and conducting leachate experiments to improve the quantification of this Ca/Sr fractionation. We are also exploring the use of isotopic tracers to study calcium biogeochemical

  11. Luminescence of the SrCl2:Pr crystals under high-energy excitation

    International Nuclear Information System (INIS)

    Antonyak, O.T.; Voloshinovskii, A.S.; Vistovskyy, V.V.; Stryganyuk, G.B.; Kregel, O.P.

    2014-01-01

    The present research was carried out in order to elucidate the mechanisms of energy transfer from the crystal lattice to Pr 3+ ions in SrCl 2 . The luminescence excitation and emission spectra as well as luminescence kinetics of the SrCl 2 :Pr single crystals containing 0.2 mol% Pr were investigated at 300 and 10 K using the vacuum ultraviolet (VUV) synchrotron radiation. The X-ray excited luminescence spectra of the SrCl 2 :Pr (C Pr =0.2 and 0.5 mol%) and SrCl 2 :Pr, K (C Pr =1.5 mol%; C K =1.5 mol%) crystals were studied at 294 and 80 K. Under optical excitation of the samples in the Pr 3+ absorption bands, there were observed five fast ultraviolet emissions assigned to the 4f 1 5d→4f 2 transitions, and two long-wave bands corresponding to the f–f transitions. Furthermore, the intrinsic emission bands of SrCl 2 were observed at 10 K. The X-ray excited luminescence spectrum of the SrCl 2 :Pr crystal containing 0.2 mol% Pr, besides intrinsic emission band near 400 nm, has got a long-wave band at about 490 nm of the Pr 3+ centers. There were not observed any emission bands of the Pr 3+ centers corresponding to the 4f 1 5d–4f 2 transitions in the X-ray excited luminescence spectrum of the SrCl 2 :Pr crystal. The possible mechanisms of energy transfer from the SrCl 2 matrix to the Pr 3+ centers are discussed. -- Highlights: • Spectral-luminescent properties of SrCl 2 :Pr have been investigated. • The identification of emission 4f–4f and 5d–4f bands of Pr 3+ ions was performed. • Adding of potassium prevents clustering of the Pr 3+ centers in the SrCl 2 :Pr, K crystals. • Under X-ray excitation at 80–300 K only Pr 3+ 4f–4f and intrinsic emission is observed

  12. Evidence for core-coupled states in 87Y from a 89Y(p, t)87Y and 88Sr(p, t)86Sr comparison

    International Nuclear Information System (INIS)

    Oelrich, I.C.; Krien, K.; DelVecchio, R.M.; Naumann, R.A.

    1976-01-01

    The 89 Y(p, t) 87 Y and 88 Sr(p, t) 86 Sr reactions were studied at 42 MeV proton energy, using a quadrupole-dipole-dipole-dipole spectograph. Comparison of excitation energies, (p, t) cross section strengths and angular distribution shapes indicates that basis features of the core-coupling model apply to these nuclei. However, mixing of single particle states with the core-coupled states is evident. The (p, t) cross-section strength summed over the 87 Y multiplet is found with few exceptions to be nearly a constant multiple of the (p, t) strength of the associated 86 Sr state

  13. Hydrologic controls on radiogenic Sr in meltwater from an alpine glacier system: Athabasca Glacier, Canada

    International Nuclear Information System (INIS)

    Arendt, C.A.; Stevenson, E.I.; Aciego, S.M.

    2016-01-01

    Filtered subglacial meltwater samples were collected daily during the onset of melt (May) and peak melt (July) over the 2011 melt season at the Athabasca Glacier (Alberta, Canada) and analyzed for strontium-87/strontium-86 ("8"7Sr/"8"6Sr) isotopic composition to infer the evolution of subglacial weathering processes. Both the underlying bedrock composition and subglacial water–rock interaction time are the primary influences on meltwater "8"7Sr/"8"6Sr. The Athabasca Glacier is situated atop Middle Cambrian carbonate bedrock that also contains silicate minerals. The length of time that subglacial meltwater interacts with the underlying bedrock and substrate is a predominant determining factor in solute concentration. Over the course of the melt season, increasing trends in Ca/K and Ca/Mg correspond to overall decreasing trends in "8"7Sr/"8"6Sr, which indicate a shift in weathering processes from the presence of silicate weathering to primarily carbonate weathering. Early in the melt season, rates of carbonate dissolution slow as meltwater approaches saturation with respect to calcite and dolomite, corresponding to an increase in silicate weathering that includes Sr-rich silicate minerals, and an increase in meltwater "8"7Sr/"8"6Sr. However, carbonate minerals are preferentially weathered in unsaturated waters. During the warmest part of a melt season the discharged meltwater is under saturated, causing an increase in carbonate weathering and a decrease in the radiogenic Sr signal. Likewise, larger fraction contributions of meltwater from glacial ice corresponds to lower "8"7Sr/"8"6Sr values, as the meltwater has lower water–rock interaction times in the subglacial system. These results indicate that although weathering of Sr-containing silicate minerals occurs in carbonate dominated glaciated terrains, the continual contribution of new meltwater permits the carbonate weathering signal to dominate. - Highlights: • Glacial meltwater "8"7Sr/"8"6Sr used to

  14. Temporal variations of Sr isotopic compositions for the rocks from Dogo, Oki islands Shimane Prefecture

    International Nuclear Information System (INIS)

    Fujimaki, Hirokazu; Xu Hong; Aoki, Ken-ichiro

    1991-01-01

    Fifty-three volcanic rocks from Dogo island, Oki, Shimane Prefecture, southwestern Japan were analyzed for Sr isotopic compositions with two basement rocks. The rock samples consist of calc-alkali rock suite, Nagaoda shoshonite-banakite suite, Oki trachyte-rhyolite suite, Dogo mugearite suite, Hei trachyte and Tsuzurao rhyolite series, and Daimanjiyama, Ohmine, Kuroshima, Shiroshimazaki, Saigo, and Misaki alkali basalt groups in the order of probable eruption sequence. The volcanic rocks of calc-alkali suite and shoshonite-banakite suite were produced before Japan Sea opening (ca. 15 Ma), and both have 87 Sr/ 86 Sr ratios higher than 0.7068. Long after Japan Sea opening Oki-trachyte-rhyolite suite was erupted (ca. 6.6 Ma); they have rather low 87 Sr/ 86 Sr ratios (0.7066-0.7081). Mugearites followed and have similar Sr isotopic composition, whereas 4.6 Ma old Daimanjiyama basalts have clearly low 87 Sr/ 86 Sr ratios (0.7050-0.7051). The rocks erupted 3-4 Ma seem to have the lowest 87 Sr/ 86 Sr ratios; they are Ohmine, Kuroshima, Shiroshimazaki alkali basalt suites (0.7044-0.7048). The 87 Sr/ 86 Sr ratios of the Saigo basalts erupted 0.84 Ma are higher than those erupted 3-4 Ma. The latest volcanic products in Dogo island, Misaki basalt suite has even higher 87 Sr/ 86 Sr ratios (0.7054-0.7057) than the Saigo basalt suite. Thus, temporal and systematic variation of Sr isotopic compositions of the volcanic rocks from Dogo can be recognized. The 87 Sr/ 86 Sr ratios of the rocks were once as high as 0.7066 or even higher than 0.708, but they started decreasing down to ca. 0.7044-0.7048 4-3 Ma ago. Since then the ratios rebounded to 0.7049-0.7055. The Hei trachyte and Tsuzurao rhyolite series are not included in this temporal and systematic change. The mantle diapir associated with Japan Sea spreading might have caused the decrease in the ratios, and either Pacific Ocean plate or Philippine Sea plate subduction may be responsible for this rebound. (author)

  15. The structure of 83Sr excited states

    International Nuclear Information System (INIS)

    Liptak, J.; Kristiak, J.; Kristiakova, K.

    1976-01-01

    The β-decay of 83 Y isomers (7.06 min and 2.85 min) have been studied by means of Ge(Li) detectors. The proposed level scheme of the 83 Sr nucleus is based on the coincidence measurement and the analysis of energy sums. The intensity balance requirement leads to αsub(T)(35.5keV)=3.2 which is consistent with M1 multipolarity of this transition. A probable structure of some of the excited states in the 83 Sr nucleus is discussed in the frame work of Alaga's model and Kuriyama's model

  16. Laser ablation inductively coupled plasma mass spectrometry. An alternative technique for monitoring 90Sr

    International Nuclear Information System (INIS)

    TsingHai Wang; Yan-Chen Lai; Yi-Kong Hsieh; Chu-Fang Wang

    2017-01-01

    Developing a rapid detection method for monitoring released 90 Sr remains a challenge to analytical chemists, particularly considering its low concentration and significant interferences in environmental samples. We proposed a concept as an alternative to detect 90 Sr on the surface of fish scales using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The high affinity of fish scales to Sr is capable of preconcentrating 90 Sr that minimizes isobaric interferences from 90 Zr + or 89 YH + , while tailing effect by abundant 88 Sr can be effectively reduced by adjusting the forward power of ICP-MS component. Adopting dried droplets of internal standards further allows a semiquantification of 90 Sr content on the surface of fish scales, which also arises an opportunity to monitoring the bioaccumulation of 90 Sr after Fukushima Daiichi nuclear disaster. (author)

  17. Domain structure and magnetic properties of epitaxial SrRuO sub 3 films grown on SrTiO sub 3 (100) substrates by ion beam sputtering

    CERN Document Server

    Oh, S H

    2000-01-01

    The domain structure of epitaxial SrRuO sub 3 thin films grown on SrTiO sub 3 (100) substrates by using ion beam sputtering has been investigated with transmission electron microscopy (TEM) and X-ray diffraction (XRD). The SrRuO sub 3 films grown in the present study revealed a unique cube-on-cube epitaxial relationship, i.e., (100) sub S sub R sub O ll (100) sub S sub T sub O , [010] sub S sub R sub O ll [101] sub S sub T sub O , prevailing with a cubic single-domain structure. The cubic SrRuO sub 3 thin films that were inherently with free from RuO sub 6 octahedron tilting exhibited higher resistivity with suppressed magnetic properties. The Curie temperature of the thin films was suppressed by 60 K from 160 K for the bulk specimen, and the saturation magnetic moment was reduced by a significant amount. The tetragonal distortion of the SrRuO sub 3 thin films due to coherent growth with the substrate seemed to result in a strong magnetic anisotropy.

  18. μSR-investigation of high-Tc superconductors at the LNP JINR phasotron

    International Nuclear Information System (INIS)

    Bezhitadze, D.T.; Borovinskaya, I.P.; Burianek, J.

    1989-01-01

    High-T c superconductors La 2-x Sr x CuO 4 (x=0+0.25), Ho(Er)Ba 2 Cu 3 O 7-y and Bi-Sr-Ca-Cu-O (the main phase 2212 with a small admixture of the 2223-phase) were investigated in the zero and 100+400 Oe transverse external magnetic fields in the temperature interval 4.2+300 K. The magnetic ordering for the La 2-x Sr x CuO 4 samples with x=0.00 and x=0.01 occurs below T N ∝250 K and T N ∝170 K respectively. A considerable increase in the distribution width of the magnetic field on the muon with an increase in the Sr-content indicates an enhancement of the Cu 2+ magnetic moment deviation from the magnetic ordering axis. The results of the analysis of the μSR spectra indicate the formation of the spin glass state in the La 1.93 Sr 0.07 CuO 4 sample. In contrast to the behaviour of the HoBa 2 Cu 3 O 7-y ceramic the magnetic ordering of the Er-atoms in the ErBa 2 Cu 3 O 7-y sample is not observed in the conparable temperature interval. Our data has also allowed the magnetic field penetration depth λ perpendicular (0) to be determined: 3200±70 A for La 1.9 Sr 0.1 CuO 4 , 2420±60 A for La 1.85 Sr 0.15 CuO 4 , 2000±50 A for Bi-Sr-Ca-Cu-O (phase 2212), 1600±50 A for ErBa 2 Cu 3 O 7-y . 20 refs.; 8 figs

  19. LCAO calculations of SrTiO3 nanotubes

    International Nuclear Information System (INIS)

    Evarestov, Robert; Bandura, Andrei

    2011-01-01

    The large-scale first-principles simulation of the structure and stability of SrTiO 3 nanotubes is performed for the first time using the periodic PBE0 LCAO method. The initial structures of the nanotubes have been obtained by the rolling up of the stoichiometric SrTiO 3 slabs consisting of two or four alternating (001) SrO and TiO 2 atomic planes. Nanotubes (NTs) with chiralities (n,0) and (n,n) have been studied. Two different NTs were constructed for each chirality: (I) with SrO outer shell, and (II) with TiO 2 outer shell. Positions of all atoms have been optimized to obtain the most stable NT structure . In the majority of considered cases the inner or outer TiO 2 shells of NT undergo a considerable reconstruction due to shrinkage or stretching of interatomic distances in the initial cubic perovskite structure. There were found two types of surface reconstruction: (1) breaking of Ti-O bonds with creating of Ti = O titanyl groups in outer surface; (2) inner surface folding due to Ti-O-Ti bending. Based on strain energy calculations the largest stability was found for (n,0) NTs with TiO 2 outer shell.

  20. Pseudogap and cuprate superconductivity: MaxEnt-μSR studies

    International Nuclear Information System (INIS)

    Boekema, C.; Schwartz, R.; Love, A.; Browne, M.C.

    2013-01-01

    Highlights: • A magnetic origin of cuprate superconductivity is plausible. • Cuprate loop currents are observed, close to predictions. • Pseudogap effects are seen above and below T c . -- Abstract: The basic physics of cuprate superconductivity is still much deliberated after 27 years of research. In contrast to phononic or polaronic roots, Varma’s theory promotes a magnetic origin. To probe cuprate magnetism, we examine zero field (ZF) muon-spin-rotation (μSR) data of RBa 2 Cu 3 O 7−δ (RBCO; R = Gd, Eu) especially near T c . Possible weak effects are analyzed using Maximum Entropy (MaxEnt, ME) to transform our μSR time series. Concerning predicted pseudogap loop currents, we have observed μSR signals in zero field for GdBCO above and now also below T c . These are near predicted fields of about 100 Oe. Using MaxEnt, we analyze transverse field (TF) μSR data of optimal doped EuBCO. Our focus is also on a temperature interval above T c to comprehend precursor effects. Our results point toward magnetic roots of cuprate superconductivity