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Sample records for razrabotka sterzhnej suz

  1. The Development of Materials for Application to Control Rod Systems in Graphite moderated Reactors; Mise au Point de Materiaux pour les Dispositifs de Controle a Barres, Utilbes dans les Reacteurs Ralentis au Graphite; Razrabotka materialov , primenyaemykh v sistemakh upravlyayushchikh sterzhnej v reaktorakh s grafitovym zamedlitelem; Perfeccionamiento de Materiales Aplicables a las Barras de Control en los Reactores Moderados por Grafito

    Energy Technology Data Exchange (ETDEWEB)

    Wade, G. E.; Kempf, F. J. [Hanford Atomic Products Operation, General Electric Company, Richland, WA (United States)

    1964-06-15

    utilizando cualquiera de los materiales mencionados. Los canales de las barras requieren a menudo un revestimiento para proteger el moderador de grafito que los circunda contra los impactos y el efecto de desgaste debidos a la insercion de las barras y para asegurar que el canal conserve la alineacion correcta. Tales revestimientos deben consistir en materiales capaces de soportar la abrasion y el impacto, dotados de gran resistencia mecanica, de reducida seccion eficaz y aptos para trabajar sin refrigeracion. Se ha ensayado con ese fin el grafito pirolitico puro y en forma de mezclas, el oxido de aluminio y el carburo de silicio. Los datos obtenidos acerca de los danos fisicos y de irradiacion indican que algunos de estos materiales se prestan para el revestimiento de los canales de las barras en los reactores. (author) [Russian] Materialy, primenjaemye v sistemah upravljajushhih i avarijnyh sterzhnej reaktorov s grafitovym zamedlitelem i teplonositelem v trubkah, mogut byt' podrazdeleny na dve kategorii: materialy dlja izgotovlenija upravljajushhih sterzhnej i materialy dlja izgotovlenija rubashek rabochih kanalov sterzhnej. Materialy dlja izgotovlenija upravljajushhih sterzhnej, naprimer bor ili gadolinij, mogut sostavljat' edinoe celoe s obolochkoj sterzhnja, kak pri ispol'zovanii boristoj nerzhavejushhej stali, primenjaemoj dlja izgotovlenija avarijnyh sterzhnej. Drugoj metod sostoit v zakljuchenii spechennogo bloka, soderzhashhego bor, naprimer B{sub 4}C -grafit ili B{sub 4}C -aljuminij, v metallicheskuju obolochku. Sterzhni poslednego tipa podhodjat dlja celej regulirovanija vvidu povyshennogo procenta soderzhanija bora. Ispytanija i opyt izgotovlenija pokazyvajut, chto pri ispol'zovanii jetih materialov mozhno skonstruirovat' razlichnye tipy udovletvoritel'nyh sterzhnej;. V kanalah sterzhnej v reaktore chasto trebujutsja rubashki dlja zashhity okruzhajushhego grafitovogo zamedlitelja ot vozdejstvija nagruzok pri vvedenii sterzhnja i iznosa i dlja podderzhanija

  2. Analysis list: Su(z)12 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Su(z)12 Embryo,Larvae + dm3 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/S...u(z)12.1.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/target/Su(z)12.5.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/dm3/target/Su(z)12.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Su(z)12.Embryo....tsv,http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Su(z)12.Larvae.tsv http://dbarchive.bioscience...dbc.jp/kyushu-u/dm3/colo/Embryo.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/colo/Larvae.gml ...

  3. The polycomb group protein Suz12 is required for embryonic stem cell differentiation

    DEFF Research Database (Denmark)

    Pasini, Diego; Bracken, Adrian P; Hansen, Jacob Bo Højberg

    2007-01-01

    results in early lethality of mouse embryos. Here, we demonstrate that Suz12(-/-) mouse embryonic stem (ES) cells can be established and expanded in tissue culture. The Suz12(-/-) ES cells are characterized by global loss of H3K27 trimethylation (H3K27me3) and higher expression levels of differentiation......-specific genes. Moreover, Suz12(-/-) ES cells are impaired in proper differentiation, resulting in a lack of repression of ES cell markers as well as activation of differentiation-specific genes. Finally, we demonstrate that the PcGs are actively recruited to several genes during ES cell differentiation, which...... despite an increase in H3K27me3 levels is not always sufficient to prevent transcriptional activation. In summary, we demonstrate that Suz12 is required for the establishment of specific expression programs required for ES cell differentiation. Furthermore, we provide evidence that PcGs have different...

  4. Suz12 is essential for mouse development and for EZH2 histone methyltransferase activity

    DEFF Research Database (Denmark)

    Pasini, Diego; Bracken, Adrian P; Jensen, Michael R

    2004-01-01

    SUZ12 is a recently identified Polycomb group (PcG) protein, which together with EZH2 and EED forms different Polycomb repressive complexes (PRC2/3). These complexes contain histone H3 lysine (K) 27/9 and histone H1 K26 methyltransferase activity specified by the EZH2 SET domain. Here we show...

  5. Adhesive pad differentiation in Drosophila melanogaster depends on the Polycomb group gene Su(z)2.

    Science.gov (United States)

    Hüsken, Mirko; Hufnagel, Kim; Mende, Katharina; Appel, Esther; Meyer, Heiko; Peisker, Henrik; Tögel, Markus; Wang, Shuoshuo; Wolff, Jonas; Gorb, Stanislav N; Paululat, Achim

    2015-04-15

    The ability of many insects to walk on vertical smooth surfaces such as glass or even on the ceiling has fascinated biologists for a long time, and has led to the discovery of highly specialized adhesive organs located at the distal end of the animals' legs. So far, research has primarily focused on structural and ultrastructural investigations leading to a deeper understanding of adhesive organ functionality and to the development of new bioinspired materials. Genetic approaches, e.g. the analysis of mutants, to achieve a better understanding of adhesive organ differentiation have not been used so far. Here, we describe the first Drosophila melanogaster mutant that develops malformed adhesive organs, resulting in a complete loss of climbing ability on vertical smooth surfaces. Interestingly, these mutants fail to make close contact between the setal tips and the smooth surface, a crucial condition for wet adhesion mediated by capillary forces. Instead, these flies walk solely on their claws. Moreover, we were able to show that the mutation is caused by a P-element insertion into the Su(z)2 gene locus. Remobilization of the P-element restores climbing ability. Furthermore, we provide evidence that the P-element insertion results in an artificial Su(z)2 transcript, which most likely causes a gain-of-function mutation. We presume that this transcript causes deregulation of yet unknown target genes involved in pulvilli differentiation. Our results nicely demonstrate that the genetically treatable model organism Drosophila is highly suitable for future investigations on adhesive organ differentiation. © 2015. Published by The Company of Biologists Ltd.

  6. Non-Destructive Testing of Plutonium-Enriched Fuel Rods; Controles non Destructifs de Barreaux Combustibles Enrichis au Plutonium; Nedestruktivnyj-kontrol' toplivnykh sterzhnej''obogashchennykh plutoniem; Ensayo no Destructivo de Elementos Combustibles Enriquecidos en Plutonio

    Energy Technology Data Exchange (ETDEWEB)

    Libotte, P.; Inniger, H.; Leblanc, J. M. [Centre D' Etude de l' Energie Nucleaire, Societe Belge pour l' Industrie Nucleaire, S.A. (Belgonucleaire), Mol (Belgium)

    1965-09-15

    la sensibilidad y la precision deseadas. La tecnica radiografica utilizada permite poner de manifiesto defectos del orden de 60 a 60 pm en las soldaduras extremas de los elementos combustibles. De las tres fracciones de polvo denso con las que se compactan por vibracion los combustibles, silo la fraccion fina esta enriquecida en plutonio. Por consiguiente, es fundamental determinar con exactitud la reparticion de este ultimo, como tambien la distribucion de densidades. La medicion de la radiacion gamma emitida por el plutonio permite conocer con precision superior a {+-}2% la distribucion de este en sentido longitudinal cuando la distribucion radial es perfecta; esta ultima se evalua principalmente por exposicion sobre una emulsion fotografica. La distribucion axial de la densidad del material combustible se determina con precision superior a {+-} 1 Degree-Sign Jo midiendo la fraccion no absorbida de los rayos gamma emitidos por una fuente externa, por ejemplo {sup 137}Cs, o bien {sup 192}Ir. Aplicando la tecnica de reflexion de ondas ultrasonicas, es posible detectar fisuras del orden de 10 {mu}m. Se estudian en la memoria las ventajas de cada una de las tecnicas no destructivas, referidas a la precision deseada y a su posible aplicacion al control automatico de los elementos combustibles plutonfferos, elaborados en escala industrial. (author) [Russian] Bel'gijskoe obshhestvo jadernoj promyshlennosti i Issledovatel'skij jadernyj centr provodjat po kontraktu v sotrudnichestve s Komissiej Evratoma issledovanija v oblasti primenenija plutonija v jenergeticheskih reaktorah s vodoj pod davleniem, V ramkah pred- prinjatyh issledovanij razrabotany razlichnye metody kontrolja bez razrushenija obrazca dlja opredelenija kachestva izgotovlennyh toplivnyh sterzhnej. Razrabotannye i opisannye v doklade opyty bjoz razrushenija obrazca ispol'zujutsja, glavnym obrazom, dlja togo, chtoby kontrolirovat' razmery i kachestvo obolochek toplivnyh sterzhnej, kachestvo svarki

  7. Quantitative mass spectrometry of histones H3.2 and H3.3 in Suz12-deficient mouse embryonic stem cells reveals distinct, dynamic post-translational modifications at Lys-27 and Lys-36

    DEFF Research Database (Denmark)

    Jung, Hye Ryung; Pasini, Diego; Helin, Kristian

    2010-01-01

    distinct coexisting modifications. In certain cases, high mass accuracy LTQ-Orbitrap MS/MS allowed precise localization of near isobaric coexisting PTMs such as trimethylation and acetylation within individual peptides. ETD MS/MS facilitated sequencing and annotation of phosphorylated histone peptides....... The combined use of ETD and CID MS/MS increased the total number of identified modified peptides. Comparative quantitative analysis of histones from wild type and Suz12-deficient ESCs using stable isotope labeling with amino acids in cell culture and LC-MS/MS revealed a dramatic reduction of H3K27me2 and H3K27......me3 and an increase of H3K27ac, thereby uncovering an antagonistic methyl/acetyl switch at H3K27. The reduction in H3K27 methylation and increase in H3K27 acetylation was accompanied by H3K36 acetylation and methylation. Estimation of the global isoform percentage of unmodified and modified histone...

  8. Design, Fabrication and Performance of Boron-Carbide Control Elements; Conception, Fabrication et Comportement de Lames de Commande en Carbure de Bore; Raschety, izgotovlenie i kharakteristiki reguliruyushchikh sterzhnej. Iz karbida Bora; Proyecto, Elaboracion y Rendimiento de Elementos de Control de Carburo de Boro

    Energy Technology Data Exchange (ETDEWEB)

    Brammer, H. A.; Jacobson, J. [General Electric Company, San Jose, CA (United States)

    1964-06-15

    acero al boro y motivos por los que se abandonaron en favor del carburo de boro. 2. Desarrollo progresivo del elemento de carburo de boro, comenzando con los primeros experimentos y las mediciones iniciales llevadas a cabo en el Vallecitos Atomic Laboratory en el marco del programa de desarrollo de materiales para barras de control de la AEC, hasta llegar a una descripcion de la configuracion definitiva de la barra de control. 3. Elaboracion de los elementos y procedimientos de control de calidad. 4. Resultados de los ensayos para determinar las caracteristicas mecanicas y la reactividad. 5. Experiencia adquirida Con los elementos y datos sobre los resultados de la inspeccion mecanica y de los ensayos de la reactividad al cabo de 2 aflos de utilizacion en los reactores. (author) [Russian] Regulirujushhee ustrojstvo s ispol'zovaniem krestoobraznoj kasety, Sostojashhej iz trubok iz nerzhavejushhej stali, zapolnennyh karbidom bora (B{sub 4}C), stali primenjat' v re aktorah s kipjashhej vodoj v aprele 1961 goda. S jetogo vremeni kasety stali standartnym jetalonom upravljajushhih sterzhnej v reaktorah s kipjashhej vodoj kompanii {sup D}zhene- ral Jelektrik{sup .} Oni zamenili kasety iz nerzhavejushhej stali s 2%-nym soderzhaniem bo r a . Jeti krestoobraznye kasety sostojat iz nabora nebol'shih vertikal'nyh trub iz nerzhavejushhej stali, zapolnennyh plotnym poroshkom karbida bora. Poroshok karbida bora pomeshhen v prodol'nom napravlenii v nezavisimyh otdalenijah putem gorjachej pakovki nad sharikopodshipnikami, razmeshhennymi, razmeshhennymi vnutri trub. R azr abotka i ispol'zovanie regulirujushhih sterzhnej iz karbida bora obsuzhdaetsja po sledujushhim pjati fazam: 1. Kratkoe opisanie opyta s pomoshh'ju stal'nyh kaset, soderzhashhih bor, i prichiny perehoda k regulirujushhim sterzhnjam iz karbida bora. 2 . Ustrojstvo kaset iz karbida bora, nachinaja s jeksperimentov po ra zrab otke i vkljuchaja samye pervye meroprijatija, provedennye v KAJe po ''Materialam dlja

  9. Use of the Neutron Die-Away Technique to Test Control Rod Effectiveness Theories; Emploi de la Methode d'Absorption des Neutrons pour Verifier les Theories sur l'Efficacite des Barres de Commande; Ispol'zovanie metoda spada potoka nejtronov dlya proverki teorij ehffektivnosti reguliruyushchikh sterzhnej; Aplicacion de la Tecnica de Extincion Neutronica a la Verificacion de las Teorias sobre la Eficacia de las Barras de Control

    Energy Technology Data Exchange (ETDEWEB)

    Perez, R. B. [University of Florida, Gainesville, FL (United States); De Saussure, G.; Silver, E. G. [University of Florida, Gainesville, FL (United States); Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1964-04-15

    actualmente determinaciones con barras de dimensiones intermedias, a fin de averiguar el limite de aplicacion de la teoria de la difusion. (author) [Russian] Raschety jeffektivnosti regulirujushhih sterzhnej uslozhnjajutsja ih zavisimost'ju kak ot raspredelenija jenergij nejtronov, tak m ot geometrii sborki. Pri sravnenii teoreticheskih dannyh s rezul'tatami jeksperimentov, provedennyh na reaktorah ili kriticheskih sistemah, voznikajut trudnosti, svjazannye s vnutrennej slozhnost'ju takih sistem. Metod spada potoka nejtronov pozvoljaet poluchit' model' vseh teplovyh nejtronov, v kotoroj raspredelenie jenergii nejtronov mozhet byt' otdeleno ot prostranstvennyh jeffektov. Pojetomu geometricheskij faktor jeffektivnosti regulirujushhego sterzhnja mozhet byt' izuchen bez ucheta detalej nejtronnogo spektra, a rezul'taty mogut byt' sravneny s rezul'tatami chistoj prostoj jeksperimental'noj ustanovki. Metod osnovan na tom fakte, chto v jeksperimente s zamiraniem nejtronov, kak on zdes' opisan, laplasian sborki svjazan s postojannoj raspada osnovnogo vida po formuljo: B{sup 2} = ({lambda} - {lambda}{sub a})/D {lambda}{sub a} gde Ha-obratnyj poluperiod nejtronov v zamedlitele (sek-1 ); D- postojannaja diffuzii (sm2 'sek-1 ). V zamedljajushhih sborkah, ispol'zuemyh dlja jetih jeksperimentov, imelis' prjamougol'nye berillievye prizmy razlichnyh razmerov, sostavlennye iz nebol'shih (7,3 h 7,3 h 5,24 sm) blokov. Ispol'zovalis' tri vida kadmievyh regulirujushhih sterzhnej: tonkie diametrom 0,476sm, krestoobraznye i polye ''tolstye'' sterzhni secheniem 7,3 X 7,3sm. Byli provereny sledujushhie teoreticheskie shemy: 1) Nordhejma -Skalettara; 2) Hurvitca-Roe; 3) Cifrovoj hod diffuzii. Jeffekt krestoobraznogo poglotitelja byl raschitan s pomoshh'ju metoda konformnogo preobrazovanija Hurvitca-Roe. Dlja laplasiana bylo polucheno znachenie 0,0188sm{sup -2}, chto sravnimo s jeksperimental'nymi rezul'tatami, sostavivshimi 0,0187 {+-} 0,0006 cm{sup -2}. Znachenija, poluchennye dlja tolstyh sterzhnej s

  10. Construction and Operation of a Commercial Gamma-Ray Package-Sterilizing Plant; Construction et fonctionnement d'une installation industrielle pour la sterilisation d'articles sous emballage par les rayons gamma; Razrabotka i ehkspluatatsiya sbornoj ustanovki gamma-izlucheniya promyshlennogo tipa dlya sterilizatsii meditsinskikh materialov; Construccion y funcionamiento de una instalacion industrial para la esterilizacion gamma de articulos medicos empaquetados

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, C. G. [Johnson' s Ethical Plastics Ltd., Slough (United Kingdom)

    1963-11-15

    Upravlenii po atomnoj ehnergii Soedinennogo Korolevstva), nastoyashchaya ustanovka byla sproektirovana spetsial'no dlya sterilizatsii plastmassovykh shpritsev i drugikh meditsinskikh materialov analogichnoj plotnosti. Ustanovka nachala funktsionirovat' s noyabrya 1962 goda. Dano opisanie osnovnykh kharakteristik i osobennostej e konstruktsii, priborov, obespechivayushchikh zashchitu obsluzhivayushchego personala, i metoda zagruzki sterzhnej. Opisan opyt ehkspluatatsii, vklyuchaya dozimetriyu, vklyuchenie ustanovki v edinyj tekhnologicheskij tsikl; privedeny rezul'taty bakteriologicheskikh issledovanij. Kratko obsuzhdeny ehkonomicheskie pokazateli pri sterilizatsii gamma-izlucheniem; dana otsenka vozmozhnosti primeneniya ustanovok podobnogo tipa v budushchem. (author)

  11. Design and Experimental Evaluation of an Electromagnetic Acceleration System for Fast Safety Rods; Etude Theorique et Experimentale d'un Mecanisme Electromagnetique d'acceleration pour des Barres de Securite; Proektirovanie i ehksperimental'naya otsenka ehlektromagnitnoj sistemy uskoreniya dlya avarijnykh sterzhnej bystrogo dejstviya; Proyecto y Estudio Experimental de un Sistema Electromagnetico de Aceleracion para Barras Rapidas de Seguridad

    Energy Technology Data Exchange (ETDEWEB)

    Dosch, P.; Kraus, H. -J.; Uhrig, H. [Kernreaktor Bau- und Betriebs-Gesellschaft m.b.H., Karlsruhe, Federal Republic of Germany (Germany)

    1964-06-15

    rapida de seguridad para un conjunto rapido de potencia nula (SNEAK). Se esta ensayando un prototipo de dicha barra. Los resultados obtenidos hasta ahora han sido muy satisfactorios. (author) [Russian] Sistema avarijnoj zashhity reaktora dolzhna dej stv ov at' s minimal'noj za d erzh k oj , esli ona prednaznachena dlja kontrolja ochen' bystryh otklonenij reaktivnosti. V jelektronnyh chastjah sistemy avarijnoj zashhity mozhno ochen' legko dobit'sja bystrogo srabatyvanija, t o gd a kak sokrashhenie vremeni m ehanicheskogo vysvobozhdenija avarijnogo sterzhnja javljaetsja trudnoj za d a ch ej. Bole etshhatel'nye issledovanija pokazyvajut, chto pomimo nebol'shogo vremeni vysvobozhdenija, preimushhestvo daet vysokaja pervonachal'naja skorost' sterzhnja. Pri odinakovom kolichestve vremeni, zatrach i v a emom na v v edenie st erzh n ja , sterzhni s ravnomernoj skorost'ju n emn ogo p revoshodjat sterzhni s ravnomernym u skoreiem . - Na osnovanii jetih soobrazhenij mozhno schi t a t' , chto impul'snoe u sk oren ie ja vlja etsja pravil'nym metodom vvedenija avarijnyh sterzhnej dlja ustranenija bystryh otklonenij r e aktivnosti, tak kak jeto daet nebol'shuju zaderzhku i obespechivaet vysokuju pervonachal'nuju skorost'. Ustanovleno, chto v avarijnyh sterzhnjah mozhno primenit' jelektromagnitnyj impul'snyj g en er ator. On imeet sledujushhie preimushhestva: a) nebol'shoe kolichestvo komponentov prostoj i prochnoj konstrukcii, kotorye mogut byt' legko vkljucheny v avarijnyj sterzhen', a takzhe mogut byt' skonstruirovany dlja u slovij, sushhestvujushhih okolo aktivnoj zony (vysokie urovni temperatury i izluchenija); b) jen ergi ja , privodjashhaja v dvizhenie sterzhni, akkumuliruetsja v jelek trok on den satore i p o jet om u takzhe mozhet byt' ispol'zovana v sluchae prekrashhenija jenergopitanija; v) konstrukciju legko mozhno prisposobit' k tomu, chtoby ona mogla svobodno i be sp r e pjatstvenno padat' v sluchae prekrashhenija impul'sov. V doklade opisyvajutsja rezul

  12. Reactor Physics Development for Advanced Gas-Cooled Reactors; Recherches en Physique des Reacteurs, pour des Reacteurs Perfectionnes Refroidis par un Gaz; Razrabotka metodov v oblasti reaktornoj fiziki dlya usovershenstvovannogo reaktora s gazovym okhlazhdeniem; Progresos de la Fisica de los Reactores de Tipo Avanzado Refrigerados por Gas

    Energy Technology Data Exchange (ETDEWEB)

    Moore, J. [United Kingdom Atomic Energy Authority (United Kingdom)

    1964-04-15

    reshetki dlja reaktora AGR i proverki teoreticheskih metodov, razrabotannyh dlja geterogennyh aktivnyh zon reaktorov, ispol'zovalis' kriticheskaja ustanovka APEX i reaktor nulevoj moshhnosti HERO s obychnymi raspolozhenijami reshetok , i kombinacijami izmenjajushhih rabotu reaktora jelementov, naprimer regulirujushhih sterzhnej. Teoreticheskie metody, razrabotannye i primenjavshiesja do nastojashhego vremeni, izvestny kak ''getrekontrol'' i FTD2. Jeksperimenty imeli cel'ju podrobno proverit' osobennosti jetih metodov, i dlja opredelenija soglasovannogo mezhdu soboj rjada konstant reshetki, sootvetstvujushhih rezul'tatam jeksperimentov, byli proanalizirovany rezul'taty izmerenij, vypolnennyh na rjade ''reaktornyh'' aktivnyh zon razlichnogo razmera v ustanovkah APEX i HERO. Jeti chisto jempiricheskie konstanty byli zatem ispol'zovany v metodah getrekontrol' i FTD2 dlja uspeshnogo planirovanija vvoda v jekspluataciju i vybora vida nagruzki dlja Uindskejlskogo AGR. Daetsja ssylka na jeksperimental'nye metody, kotorye byli provereny ilj special'no razrabotany dlja reshenija vstretivshihsja problem. Osobyj interes predstavljajut metody, ispol'zovavshiesja dlja izmerenija jeffektov reaktivnosti v reaktorah APEX, HERO i AGR i dlja opredelenija dannyh tonkoj struktury i raspredelenija jenergij v slozhnyh toplivnyh sborkah. Osushhestvljaemye v nastojashhee vremja teoreticheskie raboty skoncentrirovany, glavnym obrazom, na razrabotke al'ternativnogo metoda v otnoshenii ''getrekontrolja'' i FTD2 dlja rascheta aktivnyh zon reaktora posle znachitel'nogo vygoranija topliva. Na jetom zhe budut skoncentrirovany raboty i v budushhem. Zadachej programmy jeksperimentov na ustanovke HERO javljaetsja ispytanie jetih metodov na slozhnyh aktivnyh zonah, vkljuchaja aktivnye zony s toplivom, proizvodjashhim plutonij. Dopolnitel'nye dannye o vlijanii plutonija bydut polucheny blagodarja jekspluatacii reaktora AGR i fizicheskim izmerenijam obluchennogo topliva. (author)

  13. Razrabotka novyh transgranichnyh vodnyh marshrutov v Jugo-Vostochnoj Baltike: metodika i praktika

    Directory of Open Access Journals (Sweden)

    Kropinova E.

    2014-08-01

    Full Text Available This article offers an integrative approach to the development of trans-border water routes. Route development is analysed in the context of system approach as integration of geographical, climatic, meaning-related, infrastructural, and marketing components. The authors analyse the Russian and European approaches to route development. The article focuses on the institutional environment and tourist and recreational resources necessary for water route development. Special attention is paid to the activity aspect of tourist resources. At the same time, the development of all routes included an analysis of physical geographical, technological, infrastructural, economic, political, and social aspects. The case of water routes developed in the framework of the Crossroads 2.0 international project is used to describe the practical implementation of the theoretical assumptions. The work also tests the methodology of point rating for objects that can be potentially included in the route. The creation of trans-border water routes is presented as an innovative technology of identifying a territory’s potential and its further development. The authors stress the trans-border nature of water routes is their essential characteristic based on the natural properties of water routes.

  14. Automated setup for characterization of intact histone tails in Suz12-/- stem cells

    DEFF Research Database (Denmark)

    Sidoli, Simone; Schwämmle, Veit; Hansen, Thomas Aarup

    Epigenetics is defined as the study of heritable changes that occur without modifying the DNA sequence. Histone proteins are crucial components of epigenetic mechanisms and regulation, since they are fundamental for chromatin structure. Mass spectrometry-based proteomics is already an integrated...... developed a high-resolving and automated LC-MS/MS setup to characterize intact histone tails (middle-down strategy)...

  15. Determination of the Effectiveness of Control Rods in the VVER Reactor Fuel Assemblies; Determination de l'Efficacite des Barres de Reglage dans les Ensembles Combustibles du reacteur VVER; Opredelenie ehffektivnosti reguliruyushchikh sterzhnej v sborkakh reaktora VVEHR; Determinacion de la Eficacia de las Barras de Control en los Conjuntos de Elementos Combustibles del Reactor VVER

    Energy Technology Data Exchange (ETDEWEB)

    Semenov, V. N.; Lunin, G. L.; Komissarov, L. V.; Kamyshan, A. N.; Halizev, V. I.; Andrianov, G. Ja.; Voznesenskij, V. A.; Kuz' micheva, V. A.; Lebedev, V. I. [Ordena Lenina Institut Atomnoj Energii Im. I.V. Kurchatova, Moskva, SSSR (Russian Federation)

    1964-06-15

    The paper describes experiments done in homogeneous mock-ups of the fuel assemblies from the VVER Reactor (at one level of enrichment) to determine the effectiveness of absorbing systems comprising shim fuel assemblies or water cavities and of absorbing rods clad in jackets made of differing materials. The paper also gives data on some experiments that have been done in mock-ups of assemblies with differing levels of enrichment. These experiments make it possible to verify the methods used in calculation and to evaluate the prospects of using them for heterogeneous reactors. (author) [French] Le memoire decrit les experiences qui ont ete faites pour determiner l 'efficacite des absorbants contenus dans les barres de compensation, l'effet cavitaire et l 'efficacite des absorbants gaines de materiaux divers, au moyen d'assemblages homogenes de cartouches de combustible du reacteur VVER (reacteur de puissance ralenti et refroidi a l 'eau ayant le meme taux d'enrichissement. On y trouve en outre des donnees sur certaines experiences executees a l 'aide d'assemblages de cartouches de combustible taux d'enrichissement differents. Ces travaux permettent de verifier la methode de calcul et d'evaluer ses possibilites d'application aux reacteurs non homogenes. (author) [Spanish] Se describen en la memoria experimentos para determinar la eficacia de los materiales absorbentes contenidos en las barras de compensacion, el efecto de cavitacion y la eficacia de los materiales absorbentes revestidos de diversos materiales, realizados con ayuda de los conjuntos homogeneos de elementos combustibles del reactor VVER (reactor de potencia moderado y refrigerado por agua) con un solo grado de enriquecimiento. Ademas, se exponen datos sobre los experimentos efectuados con ayuda de conjuntos de grados de enriquecimientos; variados. Tales experimentos permiten verificar el metodo de calculo teorico, utilizad o y evaluar la posibilidad de aplicarlo a los reactores no homogeneos. (author) [Russian] V doklade opisyvajutsja jeksperimenty po opredeleniju jeffektivnosti poglotitelej kompensirujushhih kasset vodjanyh polostej i poglotitelej kompensirujushhih k a s set vodjanyh polostej i poglotitelej s chehlami iz razlichnyh materialov na odnorodnyh sborkah, sostojashhih iz kasset s razlichnym obogashheniem. Krome t o go , privodjatsja dannye po nekotorym jeksperimentam na sborkah iz kasset s razlichnym obogashheniem. Jeti jeksperimenty pozvoljajut proverit' metodiku ra sch eta i ocenit' vozmozhnosti ee primenenija dlja neodnorodnyh reaktorov . (author)

  16. Development of Non-Metallic Fuel Elements for a High-Temperature Gas-Cooled Reactor; Mise au point d'elements combustibles non metalliques pour un reacteur a haute temperature, refroidi par un gaz; Razrabotka nemetallicheskikh teplovydelyashchikh ehlementov dlya vysokotemperaturnogo reaktora s gazovym okhlazhdeniem; Elementos combustibles no metalicos para un reactor de temperatura elevada refrigerado por gas

    Energy Technology Data Exchange (ETDEWEB)

    Liebmann, B.; Schafer, L.; Spener, G. [NUKEM, Nuklear-Chemie und -Metallurgie G.m.b.H., Wolfgang bei Hanau, Federal Republic of Germany (Germany)

    1963-11-15

    In connection with fuel element development work for the high-temperature gas-coolcd reactor of the Brown-Boveri/Krupp Reaktorbau G.m.b.H., two different fuel element concepts were considered and developed. In both cases the fuel element consists of a graphite ball of 6 cm in diam. which contains the fuel insert, a cylindrical pellet of about 20 mm in diam. and 16 mm in height. The two concepts differ in the type of the.fuel insert as well as in the preparation of the graphite ball. In the first concept the fuel insert consists of a mixture of UC{sub 2} and graphite which is prepared by blending U{sub 3}O{sub 8} and graphite, pressing them into pellets and reacting the two components in a vacuum furnace at 1800{sup o}C. The atomic ratio of U : C is 1:45. Since this type of fuel pellet does not retain the fission products completely the surrounding graphite sphere had to be made impervious to fission products by impregnation in order to obtain a fission-product retaining element. Permeabilities of the order of 10{sup -6}cm{sup 2}/s could be achieved. In the second concept the fuel insert consists of a solid solution of UC in ZrC and is coated with a layer of ZrC. The molar ratio of UC to ZrC is 1 : 20. The fuel pellet preparation was accomplished by the following procedure: UO{sub 2}, ZrO{sub 2}, and graphite were mixed and pressed into pellets. The pellets were reacted to the carbides. Ball milling of the carbides was followed by hot pressing at temperatures o f 2000{sup o}C. Densities of more than 95% of the theoretical density could be achieved. A full description of the preparation and of some physical properties of the fuel pellets is given in the paper. A sufficient fission gas retention behaviour of this type of fuel insert which allows it to be put into unimpregnated graphite balls is expected. Other advantages of this kind of fuel are discussed. (author) [French] Dans le cadre des etudes de combustibles destines au reacteur a haute temperature, refroidi par un gaz, de la societe Brown-Boveri/Krupp Reaktorbau GmbH, on a retenu et mis au point deux types differents d'elements combustibles. Dans les deux cas, l'element combustible est constitue par une sphere en graphite de 6 cm de diametre enrobant un noyau de matiere combustible ayant la forme d'une pastille cylindrique d'environ 20 mm de diametre et de 16 mm de hauteur. Les deux types different par le noyau aussi bien que par la preparation de la sphere en graphite. Dans le premier type, le noyau est un melange d'UO{sub 2} et de graphite. La preparation consiste a melanger U{sub 3}O{sub 8} et du graphite, a les comprimer en pastilles et a faire reagir les deux composants du melange dans un four sous vide a 1800{sup o}C. Le rapport atomique U : C est 1:45. Etant donne que ce type de pastille ne retient pas completement les produits de fission, il a fallu impregner la sphere en graphite, de maniere a la rendre etanche aux produits de fission. On a pu realiser des permeabilites de l'ordre de 10{sup -6}cm{sup 2}/s . Dans le deuxieme type, le noyau est une solution solide de UC dans ZrC; il est revetu d'une couche de ZrC. Le rapport molaire UC : ZrC est 1 : 20. La preparation de la pastille de combustible s'effectue de la maniere suivantes UO{sub 2}, ZrO{sub 2} et le graphite sont melanges et comprimes en pastilles. On fait reagir le melange pour obtenir les carbures. Le broyage des carbures est suivi d'un pressage a chaud a des temperatures de l'ordre de 2000{sup o}C. On est parvenu a des densites egales a 95% de la densite theorique. Les auteurs decrivent en detail la preparation des pastilles de combustible et mentionnent un certain nombre de leurs proprietes physiques. On pense qu'en raison de leur capacite de retention des gaz de fission, des noyaux de ce type pourront etre enrobes dans des spheres en graphite non impregne. L'etude fait encore etat d'autres avantages de ce genre de combustible. [Spanish] En relacion con el perfeccionamiento de los elementos combustibles destinados al reactor de alta temperatura refrigerado por gas de la Brown-Boveri/Krupp Reaktorbau GmbH, se investigaron y desarrollaron dos conceptos de elemento combustible. El elemento consiste en ambos casos en una esfera de grafito de 6 cm de diametro que encierra una pastilla cilindrica de combustible de unos 20 mm de diametro y 16 mm de altura. La diferencia entre ambos conceptos estriba en el tipo de combustible y en la forma de preparar las esferas de grafito. En el primero, el combustible se prepara mezclando U{sub 3}O{sub 8} y grafito, prensando esta mezcla en pastillas y haciendo que ambos componentes reaccionen en un horno al vacio a 1800{sup o}C. La razon atomica U : C es 1:45. Como este tipo de pastilla combustible no retiene cuantitativamente los productos de fision, fue necesario impregnar la esfera de grafito para hacerla impermeable y mejorar su poder de retencion. De este modo, se lograron permeabilidades del orden de 10{sup -6}cm{sup 2}/s . Con arreglo al segundo concepto, el combustible consiste en una solucion solida de UC en ZrC recubierta de una capa de ZrC. La razon molar UC : ZrC asciende a 1 : 20. La pastilla combustible se preparo del modo siguiente: se mezclaron UO{sub 2}, ZrO{sub 2} y grafito y se prensaron en pastillas que se hicieron reaccionar para obtener los carburos, que a su vez se trituraron en un molino de bolas, para volver a prensarse a 2000{sup o}C. De este modo, se alcanzaron densidades superiores al 95% del valor teorico. La memoria describe en detalle la preparacion y algunas de las propiedades fisicas de las pastillas combustibles. Se espera que este tipo de combustible retenga suficientemente los gases de fision y permita el empleo de esferas de grafito no impregnadas. La memoria examina tambien otras ventajas de esos combustibles. [Russian] V svyazi s rabotami po sovershenstvovaniyu seplovydelyayushchikh ehlementov dlya vysokotemperaturnogo reaktora s gazovym okhlazhdeniem ''Obshchestvom stroitel'stva reaktorov Braun- Boveri/Krupp'' byli rassmotreny i razrabotany dva razlichnykh vida teplovydelyayushchikh ehlementov. Oba varianta ispol'zuyut grafitovyj sharik diametrom b sm, soderzhashchij tsilindricheskuyu tabletku topliva diametrom okolo 20 mm i vysotoj 16 mm. Oba vida teplovydelyayushchikh ehlementov razlichayutsya po tipu toplivnoj tabletki, a takzhe po metodu izgotovleniya grafitnogo sharika. Tabletka pervogo vida sostoit iz smesi UO{sub 2} i grafita, poluchennoj smeshivaniem U{sub 3}O{sub 8} s grafitom, pressovaniem tabletok i posleduyushchim vzaimodejstviem komponentov v vakuumnoj pechi pri 1800{sup o}C. Atomnoe otnoshenie U : C ravnyaetsya 1:45. Vvidu togo, chto takoj tip toplivnoj tabletki ne uderzhivaet polnost'yu produktov delenii, prishlos' obespechit' nepronitsaemost' grafitnogo sharika putem propitki, chtoby poluchit' teplovydelyayushchij ehlement, uderzhivayushchij produkty deleniya. Udalos' dostich' koehffitsientov fil'tratsii poryadka 10{sup -6} cm{sup 2}/sek. Toplivnaya tabletka vtorogo vida sostoit iz tverdogo rastvora UC v ZrC i pokryta sloem ieh ZrC. Molyarnoe otnoshenie UC:ZrC ravnyaetsya 1:20. Izgotovlenie toplivnykh tabletok provodilos' sleduyushchim sposobom: iz smesi UO{sub 2},ZrO{sub 2} i grafita otpressovyvalis' tabletki, v kotorykh komponenty vzaimodejstvovali do obrazovaniya karbidov. Izmolotye v sharovoj mel'nitse karbidy podvergalis' goryachej pressovke pri temperaturakh okolo 2000{sup o}C. Pri ehtom dostigalis' plotnosti bolee chem 95% teoreticheskoj. V rabote dano podrobnoe opisanie metoda izgotovleniya, a takzhe ukazany nekotorye fizicheskie svojstva toplivnykh tabletok. Ehtot tip toplivnykh tabletok udovletvoritel'no uderzhivaet gazoobraznye produkty deleniya, tak chto okazalos' vozmozhnym vklyuchit' ikh v nepropitannye grafitnye shariki. Obsuzhdayutsya i prochie preimushchestva reaktornykh topliv podobnogo roda. (author)

  17. Development of Geiger-Mueller counters for operation at high temperatures; Mise au point de compteurs Geiger-Mueller fonctionnant a haute temperature; Razrabotka schetchikov Gejgera-Myullera, rabotayushchikh pri povyshennoj temperature; Contadores Geiger-Mueller que funcionan a temperaturas elevadas

    Energy Technology Data Exchange (ETDEWEB)

    Draghicescu, M [Institut de Physique Atomique, Bucarest (Romania)

    1962-04-15

    Counters of this type are necessary for radioactive logging at great depths; they have to operate normally at temperatures up to 180{sup o}C. In order to preserve their characteristics under such conditions, the work function of the cathode has been improved by a special treatment. Tests have been made on counters with graphite, copper and wolfram cathodes in a glass envelope. The method is simple, and can easily be employed in industry. (author) [French] De tels compteurs sont necessaires pour le sondage radioactif aux grandes profondeurs; ils doivent fonctionner dans des conditions normales jusqu'a la temperature de 180{sup o}C. Afin qu'ils puissent conserver leurs caracteristiques jusqu'a cette temperature, on a agi sur le travail de sortie de la cathode par un traitement adequat. On a fait l'essai sur des compteurs avec cathode de graphite, de cuivre ou de tungstene, dans un ballon de verre. La methode proposee est simple et peut etre appliquee facilement dans l'industrie. (author) [Spanish] Se requiere este tipo de contador para la determinacion de la radiactividad a grandes profundidades; debe ser capaz de funcionar normalmente a temperaturas hasta de 180{sup o}C. A fin de que sus caracteristicas se conserven inalteradas hasta tales temperaturas, se ha modificado la funcion de trabajo del catodo mediante un tratamiento adecuando. Se han ensayado contadores con catodo de grafito, de cobre o de wolframio en un balon de vidrio. El metodo propuesto es simple y puede aplicarse facilmente en la industria. (author) [Russian] Podobnye schetchiki neobkhodimy dlya radioaktivnogo karottazha na bol'shikh glubinakh; oni dolzhny funktsionirovat' v normal'nykh usloviyakh pri temperature do 180{sup o}C. Nakonets, dlya togo, chtoby oni mogli sokhranyat' svoi osobennosti pri ehtoj temperature, bylo obrashcheno vnimanie na rabotu katodnogo vykhoda pri pomoshchi sootvetstvuyushchej obrabotki. Byl proveden opyt na schetchikakh s grafitovym, mednym ili vol'framovym katodom v steklyannom sosude. Predlagaemyj metod prost i mozhet byt' legko ispol'zovan v promyshlennosti. (author)

  18. Developing reports on safety analysis and probabilistic analysis of safety for operating power units at nuclear power stations with WWER reactors in Russia; Razrabotka otchetov po analizu bezopasnosti i VAB dlya ehkspluatiruyushchikhsya ehnergoblokov AEhS s WWEhR v Rossii

    Energy Technology Data Exchange (ETDEWEB)

    Malyshev, A B; Morozov, V B [ATOMENERGOPROEKT Institute, Moscow (Russian Federation)

    1999-06-01

    Report presents the current state-of art in developing safety reports and probabilistic safety analyses for WWER NPPs operated in Russia. Development of these reports and implementation of PSA is done according to the requirements outlined in the basic document `General Statement on Ensuring safety (OPB). At present submitting safety reports to the regulatory authority GAN RF is mandatory for licensing NPPs. Current state of safety reports for the operating WWER type NPPs meets generally the effective Russian standard engineering documents which are approaching the international standards. A mechanism ensuring correspondence of the safety documentation to the current state of operating units is determined. Modernization of the operating units is underway, it is aimed to eliminate existing deviations from requirements of the modern standards in the field of NPP safety

  19. Development of UO{sub 2}-Stainless Steel Fuel Plates Containing 30-50 Vol. % Oxide; Fabrication de plaques de combustible en acier inoxydable-UO{sub 2} contenant 30 a 40% d'oxyde (en volume); Razrabotka toplivnykh ehlementov iz nerzhaveyushchej stali i UO{sub 2}, soderzhashchikh 30 - 50 OB.% okisi; Elaboracion de placas de combustible de acero inoxidable UO{sub 2} conteniendo 30 a 40% de oxido (en volumen)

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, H. [Atomic Energy Research Establishment, Harwell (United Kingdom)

    1963-11-15

    This paper describes developments associated with the fabrication of UO{sub 2}-stainless steel plate type fuel elements containing up to 50 vol.% UO{sub 2}. The preparation of high-density spherical UO{sub 2} sintered particles in the 100- to 500-{mu}m size range and the compacting and sintering of cermet plate cores with the particles uniformly distributed in the stainless steel matrix are described together with procedures for hot roll-bonding the fuel plates. Rolling at temperatures up to 1300{sup o}C using total deformations in the 40% to 90% range were studied to establish optimum conditions for the production of high-density cores and to achieve good bonding between the plate components with minimum fragmentation and stringering of the UO{sub 2} particles. The manufacture of large fuel plates utilizing multi-core plates which are bonded together during hot rolling is also described. Data are presented on the mechanical properties of 30, 40 and 50 vol.% UO{sub 2}-stainless steel cermets, prepared as described above, and tested in the as ''rolled'' and annealed condition at various temperatures up to 700{sup o}C, using specimens taken laterally and longitudinally to the direction of rolling. The influence of size and uniformity of distribution of the UO{sub 2} spheres on consistency of mechanical properties are discussed. The strength of bonding between core and cladding for similar cermets in the same temperature range was also assessed. Results are also included of thermal cycling tests between 50 and 800{sup o}C, which was done to study the effects on bond stability and cermet structure after 100, 500 and 1000 cycles. (author) [French] L'auteur expose le processus de fabrication d'elements de combustible UO{sub 2}-Inox en plaques contenant jusqu'a 50% en volume d'UO{sub 2}; il decrit la preparation de particules spheriques de UO{sub 2} frittees de densite elevee (taille dans la gamme de 100 a 500), le pressage et le frittage des plaques de cermet dans lesquelles les particules de UO{sub 2} sont reparties uniformement dans la matrice en acier inoxydable, ainsi que le procede de revetement des plaques de combustible par rechargement a chaud. On a etudie des operations de laminage comprenant des deformations allant de 40% a 90%, a des temperatures allant jusqu'a 1300{sup o}C pour determiner les conditions optimums de production des noyaux de densite elevee et pour realiser une bonne cohesion entre les elements constitutifs des plaques, la fissuration des particules de UO{sub 2} etant reduite au minimum. L'auteui decrit la fabrication de grandes plaques de combustible composees de plaques a plusieurs noyaux, liees ensemble par laminage a chaud. L'auteur donne des indications sur les proprietes mecaniques de cermets UO{sub 2}-Inox contenant 30, 40 et 50% de UO{sub 2}(en volume), fabriques comme on l'a indique plus haut et essayes bruts de laminage et recuits a diverses temperatures allant jusqu'a 700{sup o}C. Il a utilise a cet effet des echantillons preleves les uns perpendiculairement, les autres parallelement au sens du laminage. Il examine en outre l'influence de la taille des particules de UO{sub 2} et de l'uniformite de leur repartition sur les proprietes mecaniques. Il a determine egalement les forces de liaison entre le noyau et la gaine pour des cermets similaires dans la meme gamme de temperatures. Le memoire contient encore les resultats d'essais de cyclage thermique entre 50 et 800{sup o}C entrepris pour determiner les effets de ce cyclage sur la structure du cermet et la stabilite de la liaison, apres 100, 500 et 1000 cycles. (author) [Spanish] La memoria expone los recientes progresos en lo relativo a la elaboracion de elementos combustibles del tipo de UO{sub 2} y acero inoxidable en placas, que contienen hasta 50% de UO{sub 2} en volumen. Describe la preparacion de particulas esfericas de UO{sub 2} sinterizado, de elevada densidad, de granulome tria comprendida entre 100 y 500, y la compactacion y sinterizacion de nucleos de cermets constituidos por placas con las particulas uniformemente distribuidas en la matriz de acero inoxidable, asi como procedimientos para unir las placas de combustible por laminacion en caliente. Se ha estudiado la laminacion a temperaturas de hasta 1300{sup o}C, utilizando deformaciones totales del orden del 40 al 90%, para determinar las condiciones optimas de produccion de nucleos de elevada densidad y obtener una union satisfactocia entre los componentes de las placas, con fragmentacion y estiraje minimos de las particulas de UO{sub 2} . Tambien se describe la fabricacion de grandes placas de combustible utilizando materiales polinucleares que se unen por laminacion en caliente. Se facilitan datos sobre las propiedades mecanicas de cermets de UO{sub 2} y acero inoxidable de 30, 40 y 50% en volumen, elaborados como se ha indicado y ensayados tal como quedan despues de laminarlos, y despues de someterlos a recocido a diversas temperaturas que alcanzaron hasta 700{sup o}C, utilizando probetas tomadas transversal y longitudinalmente con respecto a la direccion de laminado. Se examina la influencia del tamaflo y uniformidad de la distribucion de las esferas de UO{sub 2} en la estabilidad de las propiedades mecanicas. Tambien se evalua la solidez de la union entre el nucleo y el revestimiento de cermets del mismo tipo, en identico intervalo de temperaturas. Asimismo, se incluyen los resultados de los ensayos de ciclado termico efectuados entre 50 y 800{sup o}C con objeto de estudiar los efectos en la estructura del cermet y en la estabilidad de la union, despues de 100, 500 y 1000 ciclos. (author) [Russian] Daetsya opisanie protsessov izgotovleniya toplivnykh ehlementov plastinchatogo tipa iz UO{sub 2} i nerzhaveyushchej stali, soderzhashchikh do 50 ob% UO{sub 2}. Opisyvaetsya izgotovlenie ochen' plotnykh spekshikhsya sharoobraznykh chastits iz UO{sub 2} v intervale razmerov ot 100 do 500, a takzhe pressovanie i spekanie kermetnykh plastinchatykh serdechnikov s ravnomerno raspredelennymi v matritse iz nerzhaveyushchej stali chastitsami; odnovremenno opisyvayutsya metody goryachej prokatki toplivnykh plastik. Dlya opredeleniya optimal'nykh uslovij izgotovleniya ochen' plotnykh toplivnykh serdechnikov i dlya dostizheniya khoroshej svyazi mekhdu otdel'nymi plastinami i minimal'nogo drobleniya i vytyagivaniya v niti chastits UO{sub 2} byl izuchen prokat pri temperaturakh vplot' do 1300{sup o}C s ispol'zovaniem obshchej deformatsii v predelakh ot 40 do 90%. Opisyvaetsya takzhe izgotovlenie bol'shikh toplivnykh plit, iskhodya ieh neskol'kikh plastin, svyazannykh mezhdu soboyu goryachim prokatom.

  20. Polycomb repressive complex 2 (PRC2 restricts hematopoietic stem cell activity.

    Directory of Open Access Journals (Sweden)

    Ian J Majewski

    2008-04-01

    Full Text Available Polycomb group proteins are transcriptional repressors that play a central role in the establishment and maintenance of gene expression patterns during development. Using mice with an N-ethyl-N-nitrosourea (ENU-induced mutation in Suppressor of Zeste 12 (Suz12, a core component of Polycomb Repressive Complex 2 (PRC2, we show here that loss of Suz12 function enhances hematopoietic stem cell (HSC activity. In addition to these effects on a wild-type genetic background, mutations in Suz12 are sufficient to ameliorate the stem cell defect and thrombocytopenia present in mice that lack the thrombopoietin receptor (c-Mpl. To investigate the molecular targets of the PRC2 complex in the HSC compartment, we examined changes in global patterns of gene expression in cells deficient in Suz12. We identified a distinct set of genes that are regulated by Suz12 in hematopoietic cells, including eight genes that appear to be highly responsive to PRC2 function within this compartment. These data suggest that PRC2 is required to maintain a specific gene expression pattern in hematopoiesis that is indispensable to normal stem cell function.

  1. NOx reduction over metal-ion exchanged novel zeolite under lean conditions. Activity and hydrothermal stability

    International Nuclear Information System (INIS)

    Subbiah, Ayyappan; Gujar, Amit; Price, Geoffrey L.; Cho, Byong K.; Blint, Richard J.; Yie, Jae E.

    2003-01-01

    Zeolite SUZ-4 was synthesized and tested for its hydrothermal stability using a standard aging procedure coupled with NMR spectroscopy, and was identified as a promising support for lean-NO x catalysts for high temperature applications. Various metals such as Cu, Ag, Fe, Co were ion exchanged onto the SUZ-4 zeolite, and their catalytic activity for NO/NO x conversion was measured in the presence of excess oxygen using ethylene as the reducing agent. Among the metal-ions exchanged, copper proved to be the best metal cation for lean-NO x catalysis with the optimum level of exchange at 29-42%. The optimized, fresh Cu/SUZ-4 catalyst achieved 70-80% of NO/NO x conversion activity over a wide range of temperature from 350 to 600C with the maximum conversion temperature at 450C. The presence of H 2 O and SO 2 reduced the NO/NO x conversion by about 30% of the fresh Cu/SUZ-4 catalyst due possibly to the blocking of active sites for NO/NO x adsorption. Substitution of gasoline vapor for ethylene as the reductant improved the NO x reduction activity of the fresh Cu/SUZ-4 catalyst at high temperatures above 350C. Aging the Cu/SUZ-4 catalyst resulted in a slight shift of activity profile toward higher temperatures, yielding an increase of NO conversion by 16% and a decrease of NO x conversion by 15% at 525C. The effect of H 2 O and SO 2 on the aged catalyst was to reduce the NO activity by 20% and NO x activity by 30% at 500C. The effect of space velocity change was not significant except in the low temperature range where the reaction light-off occurs. Adsorption/desorption measurements indicate that aging Cu/SUZ-4 results in partial migration/agglomeration of Cu particles in the pores thereby reducing the NO/NO x activity. Overall, the NO x conversion efficiency of Cu/SUZ-4, for both fresh and aged, is much better than the benchmark Cu/ZSM-5 in the presence of H 2 O and/or SO 2

  2. A non-canonical function of Ezh2 preserves immune homeostasis

    NARCIS (Netherlands)

    Vasanthakumar, Ajithkumar; Xu, Dakang; Lun, Aaron Tl; Kueh, Andrew J.; van Gisbergen, Klaas Pjm; Iannarella, Nadia; Li, Xiaofang; Yu, Liang; Wang, Die; Williams, Bryan Rg; Lee, Stanley Cw; Majewski, Ian J.; Godfrey, Dale I.; Smyth, Gordon K.; Alexander, Warren S.; Herold, Marco J.; Kallies, Axel; Nutt, Stephen L.; Allan, Rhys S.

    2017-01-01

    Enhancer of zeste 2 (Ezh2) mainly methylates lysine 27 of histoneH3 (H3K27me3) as part of the polycomb repressive complex 2 (PRC2) together with Suz12 and Eed. However, Ezh2 can also modify non-histone substrates, although it is unclear whether this mechanism has a role during development. Here, we

  3. The Non-Destructive Testing of Fuel Elements and Their Components for the United Kingdom Power-Reactor Development Programme; Controle Non Destructif des Elements Combustibles et de Leurs Parties Constitutives dans le Cadre du Programme de Developpement des Reacteurs de Puissance au Royaume-Uni; Nedestruktivnoe ispytanie teplovydelyayushchikh ehlementov i ikh komponentov dlya osushchestvleniya programmy soedinennogo korolevstva po razrabotke ehnergeticheskikh reaktorov; Ensayo No Destructivo de Elementos Combustibles y sus Componentes, en el Marco del Programa de Reactores de Potencia del Reino Unido

    Energy Technology Data Exchange (ETDEWEB)

    Mann, C. A.; Campsie, I. C. [U.K.A.E.A., Reactor Fuel Element Laboratories, Springfields, Salwick, Preston, Lancs. (United Kingdom)

    1965-10-15

    el desplazamiento transversal de tubos ha permitido, mediante una combinacion de tecnicas, instalar un dispositivo de ensayo que puede ser manejado por personal semiespeciali- zado. Las necesidades del Laboratorio en cuanto a datos de precision sobre las dimensiones de los tubos pueden satisfacerse con un sistema automatico que registra los datos y permite prescindir del metodo laborioso y algo inexacto de anotacion manual de los resultados. En el caso de la localizacion de fallas en las varillas de combustible, el metodo expuesto en el parrafo a) puede utilizarse en general para examinar los tubos de revestimiento despues de haber efectuado la carga del combustible y de haber cerrado los extremos del tubo; ademas, la integridad del cierre se comprueba radiograficamente. Para verificar adecuadamente el estado de una soldadura circular, se toman varias radiografias. Utilizando una tecnica panoramica puede tambien registrarse con exactitud la disposicion del combustible. Se estudia ademas la posibilidad de utilizar la radiografia cromatica. La deteccion de escapes en las varillas de combustible suele realizarse utilizando un espectrometro de masas despues de haber procedido al rellenado con helio. Si este no es posible, puede aplicarse un procedimiento de contrapresion. Para localizar los escapes se utilizan los metodos ordinarios de sondeo o 'rastreo'. Un procedimiento sencillo y poco oneroso aplicable cuando se trata de lfquidos, es el de burbujeo. Se estudia la posibilidad de utilizar el kripton-85. como gas indicador. (author) [Russian] Opisyvajutsja metody ispytanij, kotorye razrabotany v laboratorijah reaktornyh teplovydeljajushhih jelementov v porjadke osushhestvlenija programmy reaktornoj gruppy po razrabotke teplovydeljajushhih jelementov v vide tonkih sterzhnej dlja rjada reaktornyh sistem. Obolochka jetih sterzhnej predstavljaet soboj trubku diametrom 5-15 mm i izgotavlivaetsja iz nerzhavejushhej stali i splavov cirkonija. a. Defektoskopija v trubkah Ul

  4. Middle-down hybrid chromatography/tandem mass spectrometry workflow for characterization of combinatorial post-translational modifications in histones.

    Science.gov (United States)

    Sidoli, Simone; Schwämmle, Veit; Ruminowicz, Chrystian; Hansen, Thomas A; Wu, Xudong; Helin, Kristian; Jensen, Ole N

    2014-10-01

    We present an integrated middle-down proteomics platform for sensitive mapping and quantification of coexisting PTMs in large polypeptides (5-7 kDa). We combined an RP trap column with subsequent weak cation exchange-hydrophilic interaction LC interfaced directly to high mass accuracy ESI MS/MS using electron transfer dissociation. This enabled automated and efficient separation and sequencing of hypermodified histone N-terminal tails for unambiguous localization of combinatorial PTMs. We present Histone Coder and IsoScale software to extract, filter, and analyze MS/MS data, including quantification of cofragmenting isobaric polypeptide species. We characterized histone tails derived from murine embryonic stem cells knockout in suppressor of zeste12 (Suz12(-/-) ) and quantified 256 combinatorial histone marks in histones H3, H4, and H2A. Furthermore, a total of 713 different combinatorial histone marks were identified in purified histone H3. We measured a seven-fold reduction of H3K27me2/me3 (where me2 and me3 are dimethylation and trimethylation, respectively) in Suz12(-) (/) (-) cells and detected significant changes of the relative abundance of 16 other single PTMs of histone H3 and other combinatorial marks. We conclude that the inactivation of Suz12 is associated with changes in the abundance of not only H3K27 methylation but also multiple other PTMs in histone H3 tails. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Non-coding RNA ANRIL and the number of plexiform neurofibromas in patients with NF1 microdeletions

    Directory of Open Access Journals (Sweden)

    Mußotter Tanja

    2012-10-01

    Full Text Available Abstract Background Neurofibromatosis type-1 (NF1 is caused by mutations of the NF1 gene at 17q11.2. In 95% of non-founder NF1 patients, NF1 mutations are identifiable by means of a comprehensive mutation analysis. 5-10% of these patients harbour microdeletions encompassing the NF1 gene and its flanking regions. NF1 is characterised by tumours of the peripheral nerve sheaths, the pathognomonic neurofibromas. Considerable inter- and intra-familial variation in expressivity of the disease has been observed which is influenced by genetic modifiers unrelated to the constitutional NF1 mutation. The number of plexiform neurofibromas (PNF in NF1 patients is a highly heritable genetic trait. Recently, SNP rs2151280 located within the non-coding RNA gene ANRIL at 9p21.3, was identified as being strongly associated with PNF number in a family-based association study. The T-allele of rs2151280, which correlates with reduced ANRIL expression, appears to be associated with higher PNF number. ANRIL directly binds to the SUZ12 protein, an essential component of polycomb repressive complex 2, and is required for SUZ12 occupancy of the CDKN2A/CDKN2B tumour suppressor genes as well as for their epigenetic silencing. Methods Here, we explored a potential association of PNF number and PNF volume with SNP rs2151280 in 29 patients with constitutional NF1 microdeletions using the exact Cochran-Armitage test for trends and the exact Mann–Whitney–Wilcoxon test. Both the PNF number and total tumour volume in these 29 NF1 patients were assessed by whole-body MRI. The NF1 microdeletions observed in these 29 patients encompassed the NF1 gene as well as its flanking regions, including the SUZ12 gene. Results In the 29 microdeletion patients investigated, neither the PNF number nor PNF volume was found to be associated with the T-allele of rs2151280. Conclusion Our findings imply that, at least in patients with NF1 microdeletions, PNF susceptibility is not associated with

  6. Chemotherapeutic Targeting of Fibulin-5 to Suppress Breast Cancer Invasion and Metastasis Stimulated by Transforming Growth Factor-Beta

    Science.gov (United States)

    2012-10-22

    al [224] observed the loss of p16INH4a expression to depress that of the polycomb genes, EZH2 and SUZ12, which collectively enhance DNA...selection of metastasis within the life history of a tumor. Cancer Res. 2007;67(24):11471–5. 13. Talmadge JE, Fidler IJ. AACR centennial series: the biology...members of the TGF-β family in vascular morpho- on the functions of natural killer cells: Depressed cy- tolytic activity and blunting of interferon

  7. Altered epigenetic regulation of homeobox genes in human oral squamous cell carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Marcinkiewicz, Katarzyna M.; Gudas, Lorraine J., E-mail: ljgudas@med.cornell.edu

    2014-01-01

    To gain insight into oral squamous cell carcinogenesis, we performed deep sequencing (RNAseq) of non-tumorigenic human OKF6-TERT1R and tumorigenic SCC-9 cells. Numerous homeobox genes are differentially expressed between OKF6-TERT1R and SCC-9 cells. Data from Oncomine, a cancer microarray database, also show that homeobox (HOX) genes are dysregulated in oral SCC patients. The activity of Polycomb repressive complexes (PRC), which causes epigenetic modifications, and retinoic acid (RA) signaling can control HOX gene transcription. HOXB7, HOXC10, HOXC13, and HOXD8 transcripts are higher in SCC-9 than in OKF6-TERT1R cells; using ChIP (chromatin immunoprecipitation) we detected PRC2 protein SUZ12 and the epigenetic H3K27me3 mark on histone H3 at these genes in OKF6-TERT1R, but not in SCC-9 cells. In contrast, IRX1, IRX4, SIX2 and TSHZ3 transcripts are lower in SCC-9 than in OKF6-TERT1R cells. We detected SUZ12 and the H3K27me3 mark at these genes in SCC-9, but not in OKF6-TERT1R cells. SUZ12 depletion increased HOXB7, HOXC10, HOXC13, and HOXD8 transcript levels and decreased the proliferation of OKF6-TERT1R cells. Transcriptional responses to RA are attenuated in SCC-9 versus OKF6-TERT1R cells. SUZ12 and H3K27me3 levels were not altered by RA at these HOX genes in SCC-9 and OKF6-TERT1R cells. We conclude that altered activity of PRC2 is associated with dysregulation of homeobox gene expression in human SCC cells, and that this dysregulation potentially plays a role in the neoplastic transformation of oral keratinocytes. - Highlights: • RNAseq elucidates differences between non-tumorigenic and tumorigenic oral keratinocytes. • Changes in HOX mRNA in SCC-9 vs. OKF6-TERT1R cells are a result of altered epigenetic regulation. • RNAseq shows that retinoic acid (RA) influences gene expression in both OKF6-TERT1R and SCC-9 cells.

  8. Altered epigenetic regulation of homeobox genes in human oral squamous cell carcinoma cells

    International Nuclear Information System (INIS)

    Marcinkiewicz, Katarzyna M.; Gudas, Lorraine J.

    2014-01-01

    To gain insight into oral squamous cell carcinogenesis, we performed deep sequencing (RNAseq) of non-tumorigenic human OKF6-TERT1R and tumorigenic SCC-9 cells. Numerous homeobox genes are differentially expressed between OKF6-TERT1R and SCC-9 cells. Data from Oncomine, a cancer microarray database, also show that homeobox (HOX) genes are dysregulated in oral SCC patients. The activity of Polycomb repressive complexes (PRC), which causes epigenetic modifications, and retinoic acid (RA) signaling can control HOX gene transcription. HOXB7, HOXC10, HOXC13, and HOXD8 transcripts are higher in SCC-9 than in OKF6-TERT1R cells; using ChIP (chromatin immunoprecipitation) we detected PRC2 protein SUZ12 and the epigenetic H3K27me3 mark on histone H3 at these genes in OKF6-TERT1R, but not in SCC-9 cells. In contrast, IRX1, IRX4, SIX2 and TSHZ3 transcripts are lower in SCC-9 than in OKF6-TERT1R cells. We detected SUZ12 and the H3K27me3 mark at these genes in SCC-9, but not in OKF6-TERT1R cells. SUZ12 depletion increased HOXB7, HOXC10, HOXC13, and HOXD8 transcript levels and decreased the proliferation of OKF6-TERT1R cells. Transcriptional responses to RA are attenuated in SCC-9 versus OKF6-TERT1R cells. SUZ12 and H3K27me3 levels were not altered by RA at these HOX genes in SCC-9 and OKF6-TERT1R cells. We conclude that altered activity of PRC2 is associated with dysregulation of homeobox gene expression in human SCC cells, and that this dysregulation potentially plays a role in the neoplastic transformation of oral keratinocytes. - Highlights: • RNAseq elucidates differences between non-tumorigenic and tumorigenic oral keratinocytes. • Changes in HOX mRNA in SCC-9 vs. OKF6-TERT1R cells are a result of altered epigenetic regulation. • RNAseq shows that retinoic acid (RA) influences gene expression in both OKF6-TERT1R and SCC-9 cells

  9. A non-canonical function of Ezh2 preserves immune homeostasis.

    Science.gov (United States)

    Vasanthakumar, Ajithkumar; Xu, Dakang; Lun, Aaron Tl; Kueh, Andrew J; van Gisbergen, Klaas Pjm; Iannarella, Nadia; Li, Xiaofang; Yu, Liang; Wang, Die; Williams, Bryan Rg; Lee, Stanley Cw; Majewski, Ian J; Godfrey, Dale I; Smyth, Gordon K; Alexander, Warren S; Herold, Marco J; Kallies, Axel; Nutt, Stephen L; Allan, Rhys S

    2017-04-01

    Enhancer of zeste 2 (Ezh2) mainly methylates lysine 27 of histone-H3 (H3K27me3) as part of the polycomb repressive complex 2 (PRC2) together with Suz12 and Eed. However, Ezh2 can also modify non-histone substrates, although it is unclear whether this mechanism has a role during development. Here, we present evidence for a chromatin-independent role of Ezh2 during T-cell development and immune homeostasis. T-cell-specific depletion of Ezh2 induces a pronounced expansion of natural killer T (NKT) cells, although Ezh2-deficient T cells maintain normal levels of H3K27me3. In contrast, removal of Suz12 or Eed destabilizes canonical PRC2 function and ablates NKT cell development completely. We further show that Ezh2 directly methylates the NKT cell lineage defining transcription factor PLZF, leading to its ubiquitination and subsequent degradation. Sustained PLZF expression in Ezh2-deficient mice is associated with the expansion of a subset of NKT cells that cause immune perturbation. Taken together, we have identified a chromatin-independent function of Ezh2 that impacts on the development of the immune system. © 2017 The Authors.

  10. Mediator complex cooperatively regulates transcription of retinoic acid target genes with Polycomb Repressive Complex 2 during neuronal differentiation.

    Science.gov (United States)

    Fukasawa, Rikiya; Iida, Satoshi; Tsutsui, Taiki; Hirose, Yutaka; Ohkuma, Yoshiaki

    2015-11-01

    The Mediator complex (Mediator) plays key roles in transcription and functions as the nexus for integration of various transcriptional signals. Previously, we screened for Mediator cyclin-dependent kinase (CDK)-interacting factors and identified three proteins related to chromatin regulation. One of them, SUZ12 is required for both stability and activity of Polycomb Repressive Complex 2 (PRC2). PRC2 primarily suppresses gene expression through histone H3 lysine 27 trimethylation, resulting in stem cell maintenance and differentiation; perturbation of this process leads to oncogenesis. Recent work showed that Mediator contributes to the embryonic stem cell state through DNA loop formation, which is strongly associated with chromatin architecture; however, it remains unclear how Mediator regulates gene expression in cooperation with chromatin regulators (i.e. writers, readers and remodelers). We found that Mediator CDKs interact directly with the PRC2 subunit EZH2, as well as SUZ12. Known PRC2 target genes were deregulated by Mediator CDK knockdown during neuronal differentiation, and both Mediator and PRC2 complexes co-occupied the promoters of developmental genes regulated by retinoic acid. Our results provide a mechanistic link between Mediator and PRC2 during neuronal differentiation. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  11. Characterization of an antagonistic switch between histone H3 lysine 27 methylation and acetylation in the transcriptional regulation of Polycomb group target genes

    DEFF Research Database (Denmark)

    Pasini, Diego; Malatesta, Martina; Jung, Hye Ryung

    2010-01-01

    Polycomb group (PcG) proteins are transcriptional repressors, which regulate proliferation and cell fate decisions during development, and their deregulated expression is a frequent event in human tumours. The Polycomb repressive complex 2 (PRC2) catalyzes trimethylation (me3) of histone H3 lysine...... are poorly understood. To gain insight into these mechanisms, we have determined the global changes in histone modifications in embryonic stem (ES) cells lacking the PcG protein Suz12 that is essential for PRC2 activity. We show that loss of PRC2 activity results in a global increase in H3K27 acetylation....... The methylation to acetylation switch correlates with the transcriptional activation of PcG target genes, both during ES cell differentiation and in MLL-AF9-transduced hematopoietic stem cells. Moreover, we provide evidence that the acetylation of H3K27 is catalyzed by the acetyltransferases p300 and CBP. Based...

  12. Visualization of multivalent histone modification in a single cell reveals highly concerted epigenetic changes on differentiation of embryonic stem cells

    DEFF Research Database (Denmark)

    Hattori, Naoko; Niwa, Tohru; Kimura, Kana

    2013-01-01

    . Bivalent modification was clearly visualized by iChmo in wild-type embryonic stem cells (ESCs) known to have it, whereas rarely in Suz12 knockout ESCs and mouse embryonic fibroblasts known to have little of it. iChmo was applied to analysis of epigenetic and phenotypic changes of heterogeneous cell......Combinations of histone modifications have significant biological roles, such as maintenance of pluripotency and cancer development, but cannot be analyzed at the single cell level. Here, we visualized a combination of histone modifications by applying the in situ proximity ligation assay, which...... population, namely, ESCs at an early stage of differentiation, and this revealed that the bivalent modification disappeared in a highly concerted manner, whereas phenotypic differentiation proceeded with large variations among cells. Also, using this method, we were able to visualize a combination...

  13. CTCF Binding Sites in the Herpes Simplex Virus 1 Genome Display Site-Specific CTCF Occupation, Protein Recruitment, and Insulator Function.

    Science.gov (United States)

    Washington, Shannan D; Musarrat, Farhana; Ertel, Monica K; Backes, Gregory L; Neumann, Donna M

    2018-04-15

    There are seven conserved CTCF binding domains in the herpes simplex virus 1 (HSV-1) genome. These binding sites individually flank the latency-associated transcript (LAT) and the immediate early (IE) gene regions, suggesting that CTCF insulators differentially control transcriptional domains in HSV-1 latency. In this work, we show that two CTCF binding motifs in HSV-1 display enhancer blocking in a cell-type-specific manner. We found that CTCF binding to the latent HSV-1 genome was LAT dependent and that the quantity of bound CTCF was site specific. Following reactivation, CTCF eviction was dynamic, suggesting that each CTCF site was independently regulated. We explored whether CTCF sites recruit the polycomb-repressive complex 2 (PRC2) to establish repressive domains through a CTCF-Suz12 interaction and found that Suz12 colocalized to the CTCF insulators flanking the ICP0 and ICP4 regions and, conversely, was removed at early times postreactivation. Collectively, these data support the idea that CTCF sites in HSV-1 are independently regulated and may contribute to lytic-latent HSV-1 control in a site-specific manner. IMPORTANCE The role of chromatin insulators in DNA viruses is an area of interest. It has been shown in several beta- and gammaherpesviruses that insulators likely control the lytic transcriptional profile through protein recruitment and through the formation of three-dimensional (3D) chromatin loops. The ability of insulators to regulate alphaherpesviruses has been understudied to date. The alphaherpesvirus HSV-1 has seven conserved insulator binding motifs that flank regions of the genome known to contribute to the establishment of latency. Our work presented here contributes to the understanding of how insulators control transcription of HSV-1. Copyright © 2018 American Society for Microbiology.

  14. Gene expression profiling of low-grade endometrial stromal sarcoma indicates fusion protein-mediated activation of the Wnt signaling pathway.

    Science.gov (United States)

    Przybyl, Joanna; Kidzinski, Lukasz; Hastie, Trevor; Debiec-Rychter, Maria; Nusse, Roel; van de Rijn, Matt

    2018-05-01

    Low-grade endometrial stromal sarcomas (LGESS) harbor chromosomal translocations that affect proteins associated with chromatin remodeling Polycomb Repressive Complex 2 (PRC2), including SUZ12, PHF1 and EPC1. Roughly half of LGESS also demonstrate nuclear accumulation of β-catenin, which is a hallmark of Wnt signaling activation. However, the targets affected by the fusion proteins and the role of Wnt signaling in the pathogenesis of these tumors remain largely unknown. Here we report the results of a meta-analysis of three independent gene expression profiling studies on LGESS and immunohistochemical evaluation of nuclear expression of β-catenin and Lef1 in 112 uterine sarcoma specimens obtained from 20 LGESS and 89 LMS patients. Our results demonstrate that 143 out of 310 genes overexpressed in LGESS are known to be directly regulated by SUZ12. In addition, our gene expression meta-analysis shows activation of multiple genes implicated in Wnt signaling. We further emphasize the role of the Wnt signaling pathway by demonstrating concordant nuclear expression of β-catenin and Lef1 in 7/16 LGESS. Based on our findings, we suggest that LGESS-specific fusion proteins disrupt the repressive function of the PRC2 complex similar to the mechanism seen in synovial sarcoma, where the SS18-SSX fusion proteins disrupt the mSWI/SNF (BAF) chromatin remodeling complex. We propose that these fusion proteins in LGESS contribute to overexpression of Wnt ligands with subsequent activation of Wnt signaling pathway and formation of an active β-catenin/Lef1 transcriptional complex. These observations could lead to novel therapeutic approaches that focus on the Wnt pathway in LGESS. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Transcriptional response of polycomb group genes to status epilepticus in mice is modified by prior exposure to epileptic preconditioning

    Directory of Open Access Journals (Sweden)

    James eReynolds

    2015-03-01

    Full Text Available Exposure of the brain to brief, non-harmful seizures can activate protective mechanisms that temporarily generate a damage-refractory state. This process, termed epileptic tolerance, is associated with large-scale down-regulation of gene expression. Polycomb group proteins are master controllers of gene silencing during development that are re-activated by injury to the brain. Here we explored the transcriptional response of genes associated with polycomb repressor complex (PRC 1 (Ring1A and Ring1B and Bmi1 and PRC2 (Ezh1, Ezh2 and Suz12, as well as additional transcriptional regulators Sirt1, Yy1 and Yy2, in a mouse model of status epilepticus. Findings were contrasted to changes after status epilepticus in mice previously given brief seizures to evoke tolerance. Real-time quantitative PCR showed status epilepticus prompted an early (1 h increase in expression of several genes in PRC1 and PRC2 in the hippocampus, followed by down-regulation of many of the same genes at later times points (4 , 8 and 24 h. Spatio-temporal differences were found among PRC2 genes in epileptic tolerance, including increased expression of Ezh2, Suz12 and Yy2 relative to the normal injury response to status epilepticus. In contrast, PRC1 complex genes including Ring 1B and Bmi1 displayed differential down-regulation in epileptic tolerance. The present study characterizes polycomb group gene expression following status epilepticus and shows prior seizure exposure produces select changes to PRC1 and PRC2 composition that may influence differential gene expression in epileptic tolerance.

  16. Neutron Tests at the Start-Up of EDF1; Les essais neutroniques au demarrage du reacteur EDF1; Nejtronnye izmereniya pri puske reaktora EDF1; Ensayos neutronicos efectuados durante la puesta en marcha del reactor EDF1

    Energy Technology Data Exchange (ETDEWEB)

    Teste du Bailler, A. [Centre d' Etudes Nucleaires de Saclay (France); Janin, R. [Electricite de France, Paris (France)

    1963-10-15

    ehksperimental'nykh metodov, razrabotannykh na reaktorakh v Markule, byla provedena vo vremya puska reaktora EDF.1. Izmereniya kasalis' glavnym obrazom ehffektivnosti upravlyayushchikh sterzhnej pri razlichnykh p ogruzh eniyakh. Opredelyaetsya skhema pod''ema s terzhnej, kotoraya pozvolyaet poluchat' polnuyu moshchnost' prk soblyudenii opredelennykh ogranichenij v temperature obolochek i gaza. Parallel'no byli provedeny izmereniya potoka pri razlichnykh polozheniyakh kompensiruyushchikh sterzhnej i pri razlichnykh zagruzkakh poglotitelej v opredelennykh kanalakh, v zavisimosti ot predvaritel'nykh raschetov v dvukhraehmernom izmerenii. Ehti izmereniya byli polucheny putem aktivatsii tochechnykh detektorov s primeneniem obychnogo metoda otravleniya vozdukha. Pri nekotorykh urovnyakh temperatury (do 140{sup o}C) byli provedeny izmereniya koehffitsientov reaktivnosti i ehffektivnosti reguliruyushchikh sterzhnej. V to zhe vremya putem aktivatsii sootvetstvuyushchikh detektorov (uran, plutonij, lyutetsij, marganets, indij, zoloto) byli provedeny izmereniya koehffitsientov spektra. Dlya izmereniya ehffektivnosti nekotorykh kompensiruyushchikh sterzhnej byl ispol'zovan ostsillyatsionnyj metod. Nakonets, s tselyakh izucheniya zashchity i povrezhdeniya grafita byli provedeny izmereniya potoka bystrykh nejtronov. (author)

  17. Control Rods in high-Flux Swimming-Pool Reactors; Les Barres de Controle dans les Piles Piscines a Haut Flux; Reguliruyushchie sterzhni dlya reaktorov bassejnovogo tipa s vysokoj plotnost'yu nejtronnogo potoka; Las Barras de Control en los Reactores Tipo Piscina de Flujo Elevado

    Energy Technology Data Exchange (ETDEWEB)

    Ageroni, P.; Blum, P.; Denielou, G.; Denis, P.; Meunier, C. [Centre d' Etudes Nucleaires de Grenoble (France)

    1964-06-15

    etudes en cours sur les barres de controle des piles piscine a coeur ouvert fonctionnant dans la bande de 10 a 30 MW. (author) [Spanish] La memoria examina los problemas planteados por las barras de control en los reactores de investigacion de tipo piscina abierta, de alta potencia especifica y elevado flujo, basandose en calculos y experimentos efectuados durante la construccion del reactor SILOE. Expone asimismo la experiencia adquirida con las barras de control mientras el reactor funcionaba a 13 MW. Examina sucesivamente: a) Los balances de reactividad y los valores de esta para los diversos tipos de barras de control que se han ensayado (cadmio, B4C, tierras raras, y combinaciones de estas sustancias); b) los picos de flujo que la presencia de barras de control crea en el cuerpo del reactor, su influencia sobre la potencia especifica, los flujos rapidos que se pueden obtener y los medios para incrementarlos; c) los problemas tecnologicos planteados por la construccion de las barras; d) los problemas de refrigeracion, vibracion, deformacion y tiempo necesario para introducirlos en el reactor. Para terminar, describe someramente loe estudios que se estan realizando con las barras de control de reactores de tipo piscina de cuerpo abierto cuando funcionan en el intervalo de potencias comprendido entre 10 y 30 MW. (author) [Russian] 1. V svete raschetov i jeksperimentov, provedennyh pri postrojke reaktora STLOE , rassmatrivajutsja problemy, voznikajushhie v svjazi s regulirujushhimi sterzhnjami dlja issledovatel'skih reaktorov otkrytogo bassejnovogo tipa s bol'shoj udel'noj moshhnost'ju i s vysokoj plotnost'ju nejtronnogo potoka. Privodjatsja takzhe rezul'taty ispytanija jetogo reaktora pri .moshhnosti 13 mgvt v svjazi s razlichnymi regulirujushhimi sterzhnjami. 2. Posledov atel'no rassmatrivajutsja sledujushhie problemy: a) balans reaktivnosti i reaktivnaja sposobnost' podvergnutyh ispytanijam regulirujushhih sterzhnej razlichnyh tipov (kadmij, B{sub 4}C , redkie zemli

  18. Difficulties and Successes in the Mass Rearing of Insects in the Laboratory, and the Possibility of Autocidal Control of some Harmful Species; Trudnosti i uspekhi massovogo razvedeniya nasekomykh v laboratorii i vozmozhnosti samoistrebleniya nekotorykh vrednykh vidov

    Energy Technology Data Exchange (ETDEWEB)

    Shumakov, E. M. [Rastenij, Vsesojuznyj Nauchno-Issledovatel' skij Institut Zashhity Leningrad, SSSR (Russian Federation)

    1968-06-15

    developing ways of overcoming the diapause in laboratory populations in order to ensure continuous rearing. This can be done either by reactivating the insects by temperature changes or by instituting a period of illumination which prevents die diapause from starting. A further possible method is that of selecting and crossing diapausing and non-diapausing strains of a given species. A number of species of Orthoptera having a fairly wide natural habitat have been used to show the possibility of autocidal control by adding to a natural population which normally has a diapause specimens of a non-diapausing population from other parts of the habitat. This possibility has been demonstrated for the cricket Teleogryllus corn modus Walk, in Australia and for sub-species of Locusta migratoria L. in the Old World. The development of this form of autocidal control of insects merits close attention. The work reported is devoted mainly to developing methods of autocidal control and techniques for mass laborarory breeding of such harmful species as Carpocapsa pomonella L., Eurygaster integriceps Put, and Locusta migratoria L. (author) [Russian] Prakticheskaja razrabotka metoda nypuska sterilizovannyh samcov, kak i voobshhe metodov samoistreblenija vrednyh nasekomyh, limitiruetsja trudnostjami massovogo razvedenija ih n iskusstvennyh uslovijah. Odnako, analiz uspeshnyh sluchaev reshenija jetoj problemy dlja rjada pidov Liplera, Lepidoptera i Orthoptera pozvoljaet nametit' vozmozhnye puti sozdanija tehniki massovogo razvedenija neobhodimyh ob{sup o}ktop. Naibolee trudnyj vopros obespechenija nasekomyh sootvetstvujushhim kormom v ljuboe vremja goda uspeshno razreshaetsja blagodarja progressu, dostignutomu v sozdanii sinteticheskih i polusinteticheskih pishhevyh sred dlja nasekomyh. Takie sredy razrabotany uzhe kak dlja polusaprofitiyh, tak i dlja rastitel'nojadnyh i hishhnyh vidov. Podbor receptov dlja takih sred opredeljaetsja pravil'nym vyborom neobhodimyh komponentov, v pervuju ochered

  19. Detection of obesity QTLs on mouse chromosomes 1 and 7 by selective DNA pooling

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, B.A.; Phillips, S.J. [Jackson Lab., Bar Harbor, ME (United States)

    1996-06-15

    The inheritance of obesity has been analyzed in an intercross between the lean 129/Sv mouse strain and the obesity-prone EL/Suz mouse strain. The weights of three major fat pads were determined on 4-month-old mice, and the sum of these weights, divided by body weight, was used as an adiposity index. The strategy of selective DNA pooling was used as a primary screen to identify putative quantitative trait loci (QTLs) affecting adiposity index. DNA pools representing the leanest 15% and fattest 15% of the F2 progeny were compared for differential allelic enrichment using widely dispersed microsatellite variants. To evaluate putative QTLs, individual genotyping and interval mapping were employed to estimate QTL effects and assess statistical significance. One QTL affecting adiposity index, which accounted for 12.3% of phenotypic variance in gender-merged data, was mapped to the central region of Chromosome (Chr) 7. The QTL allele inherited from EL conferred increased adiposity. A second QTL that accounts for 6.3% of phenotypic variance was identified on Chr 1 near D1Mitt211. At both QTLs, the data are consistent with dominant inheritance of the allele contributing to obesity. The possible relationships between these QTLs and previously described obesity QYLs, major obesity mutations, and candidate genes are discussed. 42 refs., 3 figs., 3 tabs.

  20. Myeloid malignancies: mutations, models and management

    International Nuclear Information System (INIS)

    Murati, Anne; Brecqueville, Mandy; Devillier, Raynier; Mozziconacci, Marie-Joelle; Gelsi-Boyer, Véronique; Birnbaum, Daniel

    2012-01-01

    Myeloid malignant diseases comprise chronic (including myelodysplastic syndromes, myeloproliferative neoplasms and chronic myelomonocytic leukemia) and acute (acute myeloid leukemia) stages. They are clonal diseases arising in hematopoietic stem or progenitor cells. Mutations responsible for these diseases occur in several genes whose encoded proteins belong principally to five classes: signaling pathways proteins (e.g. CBL, FLT3, JAK2, RAS), transcription factors (e.g. CEBPA, ETV6, RUNX1), epigenetic regulators (e.g. ASXL1, DNMT3A, EZH2, IDH1, IDH2, SUZ12, TET2, UTX), tumor suppressors (e.g. TP53), and components of the spliceosome (e.g. SF3B1, SRSF2). Large-scale sequencing efforts will soon lead to the establishment of a comprehensive repertoire of these mutations, allowing for a better definition and classification of myeloid malignancies, the identification of new prognostic markers and therapeutic targets, and the development of novel therapies. Given the importance of epigenetic deregulation in myeloid diseases, the use of drugs targeting epigenetic regulators appears as a most promising therapeutic approach

  1. A cytosolic Ezh1 isoform modulates a PRC2–Ezh1 epigenetic adaptive response in postmitotic cells

    KAUST Repository

    Bodega, Beatrice; Marasca, Federica; Ranzani, Valeria; Cherubini, Alessandro; Valle, Francesco Della; Neguembor, Maria Victoria; Wassef, Michel; Zippo, Alessio; Lanzuolo, Chiara; Pagani, Massimiliano; Orlando, Valerio

    2017-01-01

    The evolution of chromatin-based epigenetic cell memory may be driven not only by the necessity for cells to stably maintain transcription programs, but also by the need to recognize signals and allow plastic responses to environmental stimuli. The mechanistic role of the epigenome in adult postmitotic tissues, however, remains largely unknown. In vertebrates, two variants of the Polycomb repressive complex (PRC2-Ezh2 and PRC2-Ezh1) control gene silencing via methylation of histone H3 on Lys27 (H3K27me). Here we describe a reversible mechanism that involves a novel isoform of Ezh1 (Ezh1β). Ezh1β lacks the catalytic SET domain and acts in the cytoplasm of skeletal muscle cells to control nuclear PRC2-Ezh1 activity in response to atrophic oxidative stress, by regulating Eed assembly with Suz12 and Ezh1α (the canonical isoform) at their target genes. We report a novel PRC2-Ezh1 function that utilizes Ezh1β as an adaptive stress sensor in the cytoplasm, thus allowing postmitotic cells to maintain tissue integrity in response to environmental changes.

  2. Productive performance and industrial quality of wheat genotypes grown in two environments

    Directory of Open Access Journals (Sweden)

    Omar Possatto Junior

    Full Text Available ABSTRACT Wheat flour can be allocated for manufacturing various products, but each purpose requires specificities defined by the industrial quality. The objective of this study was to evaluate the performance of experimental lines and commercial cultivars of wheat, in South and Southeast of Brazil and to identify genotypes with favorable characteristics of industrial quality. Twenty lines in the stage of cultivation and use and three commercial cultivars were evaluated for grain yield components (hectoliter weight and thousand-grain weight and features related to the industrial quality of the flour (protein, flour stability, sedimentation with sodium dodecyl sulfate and color. The genotypes CRX/CD104//ALC, LAJ96010/JSP//ALC and CRX/ALC//ALC showed favorable characteristics for biscuit production, while the genotypes ORL97061/ORL00241//CD104, SUZ6/WEAVER//TUI/3/SUP/4/CD104, ORL99396/ORL97061//SUP, CRX/CD104//ALC, ORL98231/IOR00131//ÔNIX, ORL94346/ALC//AVT/3/ÔNIX, CEP0033/ÔNIX/3/ÔNIX*2//TC14/2*SPEAR, Campo Real/VAN//ÔNIX, ORL97061/CD 104 and PMP/ORL98231//CRX have aptitude for baking. The evaluations were efficient for the classification and selection of genotypes in the wheat breeding program.

  3. Regulation of T cell differentiation and function by EZH2

    Directory of Open Access Journals (Sweden)

    THEODOROS KARANTANOS

    2016-05-01

    Full Text Available The enhancer of zeste homologue 2 (EZH2, one of the polycomb group (PcG proteins, is the catalytic subunit of Polycomb-repressive complex 2 (PRC2 and induces the trimethylation of the histone H3 lysine 27 (H3K27me3 promoting epigenetic gene silencing. EZH2 contains a SET domain promoting the methyltransferase activity while the three other protein components of PRC2, namely EED, SUZ12 and RpAp46/48 induce compaction of the chromatin permitting EZH2 enzymatic activity. Numerous studies highlight the role of this evolutionary conserved protein as a master regulator of differentiation in humans involved in the repression of the homeotic (Hox gene and the inactivation of X-chromosome. Through its effects in the epigenetic regulation of critical genes, EZH2 has been strongly linked to cell cycle progression, stem cell pluripotency and cancer biology. Most recently, EZH2 has been associated with hematopoietic stem cell proliferation and differentiation, thymopoiesis and lymphopoiesis. Several studies have evaluated the role of EZH2 in the regulation of T cell differentiation and plasticity as well as its implications in the development of autoimmune diseases and graft versus host disease (GvHD. In this review we will briefly summarize the current knowledge regarding the role of EZH2 in the regulation of T cell differentiation, effector function and homing in the tumor microenvironment and we will discuss possible therapeutic targeting of EZH2 in order to alter T cell immune functions.

  4. Regulation of T Cell Differentiation and Function by EZH2

    Science.gov (United States)

    Karantanos, Theodoros; Christofides, Anthos; Bardhan, Kankana; Li, Lequn; Boussiotis, Vassiliki A.

    2016-01-01

    The enhancer of zeste homolog 2 (EZH2), one of the polycomb-group proteins, is the catalytic subunit of Polycomb-repressive complex 2 (PRC2) and induces the trimethylation of the histone H3 lysine 27 (H3K27me3) promoting epigenetic gene silencing. EZH2 contains a SET domain promoting the methyltransferase activity, while the three other protein components of PRC2, namely EED, SUZ12, and RpAp46/48, induce compaction of the chromatin permitting EZH2 enzymatic activity. Numerous studies highlight the role of this evolutionary conserved protein as a master regulator of differentiation in humans involved in the repression of the homeotic gene and the inactivation of X-chromosome. Through its effects in the epigenetic regulation of critical genes, EZH2 has been strongly linked to cell cycle progression, stem cell pluripotency, and cancer biology, being currently at the cutting edge of research. Most recently, EZH2 has been associated with hematopoietic stem cell proliferation and differentiation, thymopoiesis and lymphopoiesis. Several studies have evaluated the role of EZH2 in the regulation of T cell differentiation and plasticity as well as its implications in the development of autoimmune diseases and graft-versus-host disease (GVHD). The aim of this review is to summarize the current knowledge regarding the role of EZH2 in the regulation of the differentiation and function of T cells focusing on possible applications in various immune-mediated conditions, including autoimmune disorders and GVHD. PMID:27199994

  5. PARTICLE, a Triplex-Forming Long ncRNA, Regulates Locus-Specific Methylation in Response to Low-Dose Irradiation

    Directory of Open Access Journals (Sweden)

    Valerie Bríd O’Leary

    2015-04-01

    Full Text Available Exposure to low-dose irradiation causes transiently elevated expression of the long ncRNA PARTICLE (gene PARTICLE, promoter of MAT2A-antisense radiation-induced circulating lncRNA. PARTICLE affords both a cytosolic scaffold for the tumor suppressor methionine adenosyltransferase (MAT2A and a nuclear genetic platform for transcriptional repression. In situ hybridization discloses that PARTICLE and MAT2A associate together following irradiation. Bromouridine tracing and presence in exosomes indicate intercellular transport, and this is supported by ex vivo data from radiotherapy-treated patients. Surface plasmon resonance indicates that PARTICLE forms a DNA-lncRNA triplex upstream of a MAT2A promoter CpG island. We show that PARTICLE represses MAT2A via methylation and demonstrate that the radiation-induced PARTICLE interacts with the transcription-repressive complex proteins G9a and SUZ12 (subunit of PRC2. The interplay of PARTICLE with MAT2A implicates this lncRNA in intercellular communication and as a recruitment platform for gene-silencing machineries through triplex formation in response to irradiation.

  6. A Novel Role of Silibinin as a Putative Epigenetic Modulator in Human Prostate Carcinoma

    Directory of Open Access Journals (Sweden)

    Ioannis Anestopoulos

    2016-12-01

    Full Text Available Silibinin, extracted from milk thistle (Silybum marianum L., has exhibited considerable preclinical activity against prostate carcinoma. Its antitumor and chemopreventive activities have been associated with diverse effects on cell cycle, apoptosis, and receptor-dependent mitogenic signaling pathways. Here we hypothesized that silibinin’s pleiotropic effects may reflect its interference with epigenetic mechanisms in human prostate cancer cells. More specifically, we have demonstrated that silibinin reduces gene expression levels of the Polycomb Repressive Complex 2 (PRC2 members Enhancer of Zeste Homolog 2 (EZH2, Suppressor of Zeste Homolog 12 (SUZ12, and Embryonic Ectoderm Development (EED in DU145 and PC3 human prostate cancer cells, as evidenced by Real Time Polymerase Chain Reaction (RT-PCR. Furthermore immunoblot and immunofluorescence analysis revealed that silibinin-mediated reduction of EZH2 levels was accompanied by an increase in trimethylation of histone H3 on lysine (Κ-27 residue (H3K27me3 levels and that such response was, in part, dependent on decreased expression levels of phosphorylated Akt (ser473 (pAkt and phosphorylated EZH2 (ser21 (pEZH2. Additionally silibinin exerted other epigenetic effects involving an increase in total DNA methyltransferase (DNMT activity while it decreased histone deacetylases 1-2 (HDACs1-2 expression levels. We conclude that silibinin induces epigenetic alterations in human prostate cancer cells, suggesting that subsequent disruptions of central processes in chromatin conformation may account for some of its diverse anticancer effects.

  7. Multifaceted role of EZH2 in breast and prostate tumorigenesis: epigenetics and beyond.

    Science.gov (United States)

    Deb, Gauri; Thakur, Vijay S; Gupta, Sanjay

    2013-05-01

    Overexpression of EZH2 and other PRC2 subunits, such as SUZ12, is associated with tumor progression and poor prognosis in several human malignancies. Nevertheless, the underlying mechanisms driving aberrant EZH2 expression are poorly understood. This review provides molecular insights into the essential role of EZH2 in breast and prostate tumorigenesis. We addressed the current understanding on the oncogenic role of EZH2, with an emphasis on: (1) the less known PRC2-independent role of EZH2 in gene activation, in addition to its canonical role in transcriptional silencing as a histone methyltransferase catalyzing the trimethylation of histone H3 at lysine 27; (2) causes and consequences of its deregulation in tumor cells and; (3) collaboration of EZH2 with other epigenetic and hormone receptor-mediated oncogenic signaling pathways. We also summarize how EZH2 has emerged as a promising therapeutic target in hormone-refractory cancers and the prospects for integrating EZH2 blockade with available pharmacological inhibitors.

  8. A cytosolic Ezh1 isoform modulates a PRC2–Ezh1 epigenetic adaptive response in postmitotic cells

    KAUST Repository

    Bodega, Beatrice

    2017-03-27

    The evolution of chromatin-based epigenetic cell memory may be driven not only by the necessity for cells to stably maintain transcription programs, but also by the need to recognize signals and allow plastic responses to environmental stimuli. The mechanistic role of the epigenome in adult postmitotic tissues, however, remains largely unknown. In vertebrates, two variants of the Polycomb repressive complex (PRC2-Ezh2 and PRC2-Ezh1) control gene silencing via methylation of histone H3 on Lys27 (H3K27me). Here we describe a reversible mechanism that involves a novel isoform of Ezh1 (Ezh1β). Ezh1β lacks the catalytic SET domain and acts in the cytoplasm of skeletal muscle cells to control nuclear PRC2-Ezh1 activity in response to atrophic oxidative stress, by regulating Eed assembly with Suz12 and Ezh1α (the canonical isoform) at their target genes. We report a novel PRC2-Ezh1 function that utilizes Ezh1β as an adaptive stress sensor in the cytoplasm, thus allowing postmitotic cells to maintain tissue integrity in response to environmental changes.

  9. Measurements of Void Effects in the Zero-Power Critical Facility NORA; Mesures de l'Effet Cavitaire dans l'Ensemble Critique NORA de Puissance Zero; Izmerenie vliyaniya pustot v kriticheskoj ustanovke nulevoj moshchnosti NORA; DeterminaciOn de los Efectos de CavitaciOn en el Conjunto Critico NORA de Potencia Nula

    Energy Technology Data Exchange (ETDEWEB)

    Bryhn-Ingebrigtsen, K.; Eriksen, V. O.; Schatvet, J.; Ukkestad, A.; Wood, J. I.; Ofjord, K. [Kjeller Research Establishment (Norway)

    1964-02-15

    gruppami sterzhnej provedeny staticheski. Daetsya opisanie ehksperimental'nykh metodov vmeste s primerami ikh primeneniya dlya izmereniya vliyaniya pustoty edinichnogo sterzhnya, vzaimodejstviya sterzhnej s pustotami i vliyaniya polnost'yu pustotnoj aktivnoj zony. (author)

  10. Operating Experience with Indian Point Nuclear Electric Generating Station; Experience d'exploitation de la centrale nucleaire d'Indian point; Opyt ehkspluatatsii Indian-pojntskoj yadernoj ehlektrostantsii; Experiencia adquirida con la explotacion de la central nucleoelectrica de Indian point

    Energy Technology Data Exchange (ETDEWEB)

    Beattie, W. C.; Freyberg, R. H. [Consolidated Edison Company of New York, Inc., New York, NY (United States)

    1963-10-15

    'yu 275 tys. kvt. Toplivom v reaktore sluzhit smes' polnost'yu obogashchennoj okisi U{sup 235} i okisi Th{sup 232}. Stantsiya raspolozhena na reke Gudzon, primerno v 24 milyakh severnee N'yu-Jorka. V svyazi s takoj blizost'yu ot N'yu-Jorka v proekte stantsii byli predusmotreny dopolnitel'nye predokhranitel'nye ustrojstva dlya predotvrashcheniya otkloneniya reaktivnosti i radiatsionnykh ehffektov takogo otkloneniya. Stroitel'stvo zakoncheno v mae 1962 goda. Zagruzka topliva osushchestvlena v iyune, a 2 avgusta 1962 goda reaktor vpervye dostig kritichnosti. V techenie avgusta privodilis' ispytaniya ka maloj moshchnosti do 5 mgvt pri temperature okrukhaitsej sredy i povyshennoj temperature. 16 sentyabrya 1962 goda turbogenerator byl vpervye fazirovan s sistemoj Konsolidejtid Ehdison. Ispytanie reaktora na moshchnostyakh do 50% provodilos' do noyabrya i preryvalos' chastymi avtomaticheskimiostanovkami, bol'shaya chast' kotorykh byla vyzvana nepoladkami v neyadernoj chasti stantsii. Nepoladki v sisteme upravleniya privodov reguliruyushchikh sterzhnej byli samymi ser'eznymi pomekhami so storony yadernoj chasti stantsii dlya raboty s avtomaticheskim vvedeniem reguliruyushchikh sterzhnej i prichinoj zaderzhek s puskom reaktora posle avtomaticheskikh ostanovok. 14 noyabrya 1962 goda stantsiya byla ostanovlena dlya planovoj zameny truboprovodov v neyadernoj chasti stantsii i modifikatsij i dopolneniya sistemy provodov reguliruyushchikh sterzhnej. Poslednee vklyuchalo ustanovku sistemy ochistki sukhogo azota dlya kozhukhov privodov reguliruyushchikh sterzhnej, prednaznachennykh dlya svedeniya k minimumu ehffektov vody, prosachivayushchejsya cherez uplotneniya v kozhukhi reguliruyushchikh sterzhnej. Okazalos', chto ehto yavlyaetsya osnovnoj prichinoj nepravil'nykh pokazanij sistemy upravleniya reaktorom. Blok byl vnov' pushchen 1 yanvarya 1963 goda. Ispytanie reaktora na moshchnostyakh do 100% v usloviyakh stabil'noj nagruzki bylo zakoncheno 27 yanvarya 1963 goda. Rezul

  11. Ultimate Disposal of High-Level Radioactive Wastes - Fixation in Phosphate Glass with Emphasis on the Continuous Mode of Plant Operation; Elimination Definitive de Dechets de Haute Activite - Fixation dans du Verre au Phosphate en Vue d'une Exploitation de l'Installation en Continu; ОКОНЧАТЕЛЬНОЕ УДАЛЕНИЕ ВЫСОКОАКТИВНЫХ ОТХОДОВ - ФИКСАЦИЯ В ФОСФАТНОМ СТЕКЛЕ НА НЕПРЕРЫВНО РАБОТАПЦЕЙ УСТАНОВКЕ; Evacuacion Definitiva de Desechos de Elevada Radiactividad. Fijacion en Vidrio al Fosfato Atendiendo Particularmente a la Continuidad de la Marcha de la Instalacion

    Energy Technology Data Exchange (ETDEWEB)

    Hatch, L. P.; Weth, G. C.; Tuthill, E. J. [Brookhaven National Laboratory, Upton, Long Island, NY (United States)

    1963-02-15

    en la explotacion de una instalacion experimental de una capacidad de elaboracion de 0,5 pies{sup 3} (14 dm{sup 9}) de vidrio por dia, con alimentacion continua de desechos inactivos simulados. (author) [Russian] Pri izuchenii metodov okonchatel'nogo udalenija vysokoaktivnyh othodov v Brukhejvenskoj nacional'noj laboratorii osoboe vnimanie udeljaetsja poluchenie fosfatnyh stekol kak sposobu vkljuchenie produktov delenija v ustojchivuju sredu. Glavnyj interes predstavljaet razrabotka processa, pri kotorom vodnye othody prevrashhalis' by v okonchatel'nyj steklovidnyj produkt v polnost'ju zhidkoj sisteme. Metod poluchenija fosfatnogo stekla predstavljaet celyj rjad vazhnyh v jetom otnoshenii preimushhestv i, v chastnosti, daet vozmozhnost' razrabotat' nepreryvnyj process* v kotorom zhidkaja sreda mozhet legko napravljat'sja iz odnoj stadii processa v druguju. V doklade privodjatsja rezul'taty provodimyh v laboratornom masshtabe issledovanij po nepre ryvnomu polucheniju fosfatnyh stekol s ispol'zovaniem raznogo roda vodnyh othodov. Jeti issledovanija prodolzhalis' v techenie oklo 20 mesjacev, ih cel'ju bylo opredelenie vazhnejshih rabochih parametrov, prichem osoboe vnimanie udeljalos' korrozionnoj stojkosti i fizicheskoj sohrannosti tiglja. rabotajushhego pri vysokoj temperature. Pomimo jetogo, v doklade obsuzhdaetsja razrabotka tehnologicheskoj shemy, a takzhe konstrukcija i rezul'taty raboty promyshlennoj ustanovki s proizvoditel'nost'ju v 0,5 kubicheskih futov stekla v sutki pri nepreryvnoj podache neradioaktivnogo rastvora, imitirujushhego othody. (author)

  12. SVA retrotransposon insertion-associated deletion represents a novel mutational mechanism underlying large genomic copy number changes with non-recurrent breakpoints

    Science.gov (United States)

    2014-01-01

    Background Genomic disorders are caused by copy number changes that may exhibit recurrent breakpoints processed by nonallelic homologous recombination. However, region-specific disease-associated copy number changes have also been observed which exhibit non-recurrent breakpoints. The mechanisms underlying these non-recurrent copy number changes have not yet been fully elucidated. Results We analyze large NF1 deletions with non-recurrent breakpoints as a model to investigate the full spectrum of causative mechanisms, and observe that they are mediated by various DNA double strand break repair mechanisms, as well as aberrant replication. Further, two of the 17 NF1 deletions with non-recurrent breakpoints, identified in unrelated patients, occur in association with the concomitant insertion of SINE/variable number of tandem repeats/Alu (SVA) retrotransposons at the deletion breakpoints. The respective breakpoints are refractory to analysis by standard breakpoint-spanning PCRs and are only identified by means of optimized PCR protocols designed to amplify across GC-rich sequences. The SVA elements are integrated within SUZ12P intron 8 in both patients, and were mediated by target-primed reverse transcription of SVA mRNA intermediates derived from retrotranspositionally active source elements. Both SVA insertions occurred during early postzygotic development and are uniquely associated with large deletions of 1 Mb and 867 kb, respectively, at the insertion sites. Conclusions Since active SVA elements are abundant in the human genome and the retrotranspositional activity of many SVA source elements is high, SVA insertion-associated large genomic deletions encompassing many hundreds of kilobases could constitute a novel and as yet under-appreciated mechanism underlying large-scale copy number changes in the human genome. PMID:24958239

  13. Long non-coding RNA profile in mantle cell lymphoma identifies a functional lncRNA ROR1-AS1 associated with EZH2/PRC2 complex

    Science.gov (United States)

    Hu, Guangzhen; Gupta, Shiv K.; Troska, Tammy P.; Nair, Asha; Gupta, Mamta

    2017-01-01

    Mantle cell lymphoma (MCL) is an aggressive B-cell lymphoma characterized by rapid disease progression. The needs for new therapeutic strategies for MCL patients call for further understanding on the molecular mechanisms of pathogenesis of MCL. Recently, long noncoding RNAs (lncRNAs) have been recognized as key regulators of gene expression and disease development, however, the role of lncRNAs in non-Hodgkin lymphoma and specifically in MCL is still unknown. Next generation RNA-sequencing was carried out on MCL patient samples along with normal controls and data was analyzed. As a result, several novel lncRNAs were found significantly overexpressed in the MCL samples with lncRNA ROR1-AS1 the most significant one. We cloned the ROR1-AS1 lncRNA in expression vector and ectopically transfected in MCL cell lines. Results showed that overexpression of ROR1-AS1 lncRNA promoted growth of MCL cells while decreased sensitivity to the treatment with drugs ibrutinib and dexamethasone. ROR-AS1 overexpression also decreased the mRNA expression of P16 (P = 0.21), and SOX11 (p = 0.017), without much effect on P53, ATM and P14 mRNA. RNA-immunoprecipitation assays demonstrated high affinity binding of lncRNA ROR1-AS1 with EZH2 and SUZ12 proteins of the polycomb repressive complex-2 (PRC2). Suppressing EZH2 activity with pharmacological inhibitor GSK343 abolished binding of ROR1-AS1 with EZH2. Taken together, this study identified a functional lncRNA ROR-AS1 involved with regulation of gene transcription via associating with PRC2 complex, and may serve as a novel biomarker in MCL patients. PMID:29113297

  14. Lineage specific expression of Polycomb Group Proteins in human embryonic stem cells in vitro.

    Science.gov (United States)

    Pethe, Prasad; Pursani, Varsha; Bhartiya, Deepa

    2015-05-01

    Human embryonic (hES) stem cells are an excellent model to study lineage specification and differentiation into various cell types. Differentiation necessitates repression of specific genes not required for a particular lineage. Polycomb Group (PcG) proteins are key histone modifiers, whose primary function is gene repression. PcG proteins form complexes called Polycomb Repressive Complexes (PRCs), which catalyze histone modifications such as H2AK119ub1, H3K27me3, and H3K9me3. PcG proteins play a crucial role during differentiation of stem cells. The expression of PcG transcripts during differentiation of hES cells into endoderm, mesoderm, and ectoderm lineage is yet to be shown. In-house derived hES cell line KIND1 was differentiated into endoderm, mesoderm, and ectoderm lineages; followed by characterization using RT-PCR for HNF4A, CDX2, MEF2C, TBX5, SOX1, and MAP2. qRT-PCR and western blotting was performed to compare expression of PcG transcripts and proteins across all the three lineages. We observed that cells differentiated into endoderm showed upregulation of RING1B, BMI1, EZH2, and EED transcripts. Mesoderm differentiation was characterized by significant downregulation of all PcG transcripts during later stages. BMI1 and RING1B were upregulated while EZH2, SUZ12, and EED remained low during ectoderm differentiation. Western blotting also showed distinct expression of BMI1 and EZH2 during differentiation into three germ layers. Our study shows that hES cells differentiating into endoderm, mesoderm, and ectoderm lineages show distinct PcG expression profile at transcript and protein level. © 2015 International Federation for Cell Biology.

  15. Characterization of histone H3K27 modifications in the β-globin locus

    International Nuclear Information System (INIS)

    Kim, Yea Woon; Kim, AeRi

    2011-01-01

    Research highlights: → The β-globin locus control region is hyperacetylated and monomethylated at histone H3K27. → Highly transcribed globin genes are marked by H3K27ac, but H3K27me2 is remarkable at silent globin genes in erythroid K562 cells. → Association of PRC2 subunits is comparable with H3K27me3 pattern. → Modifications of histone H3K27 are established in an enhancer-dependent manner. -- Abstract: Histone H3K27 is acetylated or methylated in the environment of nuclear chromatin. Here, to characterize the modification pattern of H3K27 in locus control region (LCR) and to understand the correlation of various H3K27 modifications with transcriptional activity of genes, we analyzed the human β-globin locus using the ChIP assay. The LCR of the human β-globin locus was enriched by H3K27ac and H3K27me1 in erythroid K562 cells. The highly transcribed globin genes were hyperacetylated at H3K27, but the repressed globin genes were highly dimethylated at this lysine in these cells. However, in non-erythroid 293FT cells, the β-globin locus was marked by a high level of H3K27me3. EZH2 and SUZ12, subunits of polycomb repressive complex 2, were comparably detected with the H3K27me3 pattern in K562 and 293FT cells. In addition, H3K27ac, H3K27me1 and H3K27me3 were established in an enhancer-dependent manner in a model minichromosomal locus containing an enhancer and its target gene. Taken together, these results show that H3K27 modifications have distinctive correlations with the chromatin state or transcription level of genes and are influenced by an enhancer.

  16. Chinese herbal medicine use in Taiwan during pregnancy and the postpartum period: a population-based cohort study.

    Science.gov (United States)

    Chuang, Chao-Hua; Chang, Pei-Jen; Hsieh, Wu-Shiun; Tsai, Yih-Jian; Lin, Shio-Jean; Chen, Pau-Chung

    2009-06-01

    Using Chinese herbal medicines during pregnancy and postpartum is common in the Chinese community. The purpose of this current study is to explore the use of Chinese herbal medicines by women during pregnancy and postpartum in Taiwan. It is an on-going prospective longitudinal study design. We used multistage stratified systematic sampling to recruit 24,200 pairs, postpartum women and newborns, from the Taiwan national birth register in 2005. Subjects underwent a home interview 6 months after their deliveries between June 2005 and July 2006. A structured questionnaire was successfully administered to 87.8% of the sampled population. At least one Chinese herbal medicine was used by 33.6% and 87.7% of the interviewed subjects during pregnancy and the postpartum period, respectively. An-Tai-Yin, Pearl powder, and Huanglian were the most commonly used during pregnancy, while Shen-Hua-Tang and Suz-Wu-Tang were the most commonly used by postpartum women. Pregnant women aged 20-34, with high education, threatened abortion, chronic disease, and primipara appeared to use more Chinese herbal medicines than others in the sample. Postpartum women with high education, primipara, normal spontaneous delivery, and breastfeeding were found to use more Chinese herbal medicines; but women with pregnancy-related illness used less. Chinese herbal medicines are frequently used by women during pregnancy and the postpartum period in Taiwan and those with high education and primipara used more such herbs. Due to limited safety information on these herbs, we would advise caution regarding their use either during pregnancy or postpartum breastfeeding period. Moreover, it is important for nurses/midwifes enquiring about such habits, and providing the adequate education to women during prenatal and postpartum care to prevent potential side effects.

  17. Analysis of genomic aberrations and gene expression profiling identifies novel lesions and pathways in myeloproliferative neoplasms

    International Nuclear Information System (INIS)

    Rice, K L; Lin, X; Wolniak, K; Ebert, B L; Berkofsky-Fessler, W; Buzzai, M; Sun, Y; Xi, C; Elkin, P; Levine, R; Golub, T; Gilliland, D G; Crispino, J D; Licht, J D; Zhang, W

    2011-01-01

    Polycythemia vera (PV), essential thrombocythemia and primary myelofibrosis, are myeloproliferative neoplasms (MPNs) with distinct clinical features and are associated with the JAK2V617F mutation. To identify genomic anomalies involved in the pathogenesis of these disorders, we profiled 87 MPN patients using Affymetrix 250K single-nucleotide polymorphism (SNP) arrays. Aberrations affecting chr9 were the most frequently observed and included 9pLOH (n=16), trisomy 9 (n=6) and amplifications of 9p13.3–23.3 (n=1), 9q33.1–34.13 (n=1) and 9q34.13 (n=6). Patients with trisomy 9 were associated with elevated JAK2V617F mutant allele burden, suggesting that gain of chr9 represents an alternative mechanism for increasing JAK2V617F dosage. Gene expression profiling of patients with and without chr9 abnormalities (+9, 9pLOH), identified genes potentially involved in disease pathogenesis including JAK2, STAT5B and MAPK14. We also observed recurrent gains of 1p36.31–36.33 (n=6), 17q21.2–q21.31 (n=5) and 17q25.1–25.3 (n=5) and deletions affecting 18p11.31–11.32 (n=8). Combined SNP and gene expression analysis identified aberrations affecting components of a non-canonical PRC2 complex (EZH1, SUZ12 and JARID2) and genes comprising a ‘HSC signature' (MLLT3, SMARCA2 and PBX1). We show that NFIB, which is amplified in 7/87 MPN patients and upregulated in PV CD34+ cells, protects cells from apoptosis induced by cytokine withdrawal

  18. Senescence-Associated Molecular and Epigenetic Alterations in Mesenchymal Stem Cell Cultures from Amniotic Fluid of Normal and Fetus-Affected Pregnancy

    Directory of Open Access Journals (Sweden)

    Jūratė Savickienė

    2016-01-01

    Full Text Available Human amniotic-fluid-derived mesenchymal stem cells (AF-MSCs are interesting for their multilineage differentiation potential and wide range of therapeutic applications due to the ease of culture expansion. However, MSCs undergo replicative senescence. So far, the molecular mechanisms that underlie fetal diseases and cell senescence are still poorly understood. Here, we analyzed senescence-associated morphologic, molecular, and epigenetic characteristics during propagation of MSCs derived from AF of normal and fetus-affected pregnancy. AF-MSCs cultures from both cell sources displayed quite similar morphology and expression of specific cell surface (CD44, CD90, and CD105 and stemness (Oct4, Nanog, Sox2, and Rex1 markers but had interindividual variability in proliferation capability and time to reach senescence. Within passages 4 and 8, senescent cultures exhibited typical morphological features, senescence-associated β-galactosidase activity, increased levels of p16, and decreased levels of miR-17 and miR-21 but showed differential expression of p21, p53, and ATM dependently on the onset of cell senescence. These differences correlated with changes in the level of chromatin modifiers (DNMT1 and HDAC1 and polycomb group proteins (EZH2, SUZ12, and BMI1 paralleling with changes in the expression of repressive histone marks (H3K9me3 and H3K27me3 and stemness markers (Oct4, Nanog, Sox2, and Rex1. Therefore epigenetic factors are important for AF-MSCs senescence process that may be related with individuality of donor or a fetus malignancy status.

  19. 3-Deazaneplanocin A suppresses aggressive phenotype-related gene expression in an oral squamous cell carcinoma cell line

    International Nuclear Information System (INIS)

    Hatta, Mitsutoki; Naganuma, Kaori; Kato, Kenichi; Yamazaki, Jun

    2015-01-01

    In tumor tissues, alterations of gene expression caused by aberrant epigenetic modifications confer phenotypic diversity on malignant cells. Although 3-deazaneplanocin A (DZNep) has been shown to reactivate tumor suppressor genes in several cancer cells, it remains unclear whether DZNep attenuates the malignant phenotypes of oral squamous cell carcinoma (OSCC) cells. In this study, we investigated the effect of DZNep on the expression of genes related to aggressive phenotypes, such as epithelial–mesenchymal transition, in OSCC cells. We found that DZNep reduced the cellular levels of polycomb group proteins (EZH2, SUZ12, BMI1, and RING1A) and the associated trimethylation of Lys27 on histone H3 and monoubiquitination of Lys119 on histone H2A in the poorly differentiated OSCC cell line SAS. Immunocytochemical staining demonstrated that DZNep induced the reorganization of filamentous actin and the membrane localization of E-cadherin associated with cell–cell adhesions. We also found an inhibitory effect of DZNep on cell proliferation using a WST assay. Finally, quantitative RT-PCR analysis demonstrated that genes involved in the aggressive phenotypes (TWIST2, EGFR, ACTA2, TGFB1, WNT5B, and APLIN) were down-regulated, whereas epithelial phenotype genes (CDH1, CLDN4, IVL, and TGM1) were up-regulated in SAS cells treated with DZNep. Collectively, our findings suggest that DZNep reverses the aggressive characteristics of OSCC cells through the dynamic regulation of epithelial plasticity via the reprogramming of gene expression patterns. - Highlights: • DZNep reduced PcG proteins and associated histone modifications in OSCC cells. • DZNep enhanced cell–cell adhesion indicative of epithelial phenotype in OSCC cells. • DZNep suppressed the aggressive phenotype-related gene expression in OSCC cells. • DZNep activated the gene expression of epithelial markers in OSCC cells.

  20. 3-Deazaneplanocin A suppresses aggressive phenotype-related gene expression in an oral squamous cell carcinoma cell line

    Energy Technology Data Exchange (ETDEWEB)

    Hatta, Mitsutoki, E-mail: hatta@college.fdcnet.ac.jp [Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka (Japan); Naganuma, Kaori [Department of Oral and Maxillofacial Surgery, Fukuoka Dental College, Fukuoka (Japan); Kato, Kenichi; Yamazaki, Jun [Department of Physiological Science and Molecular Biology, Fukuoka Dental College, Fukuoka (Japan)

    2015-12-04

    In tumor tissues, alterations of gene expression caused by aberrant epigenetic modifications confer phenotypic diversity on malignant cells. Although 3-deazaneplanocin A (DZNep) has been shown to reactivate tumor suppressor genes in several cancer cells, it remains unclear whether DZNep attenuates the malignant phenotypes of oral squamous cell carcinoma (OSCC) cells. In this study, we investigated the effect of DZNep on the expression of genes related to aggressive phenotypes, such as epithelial–mesenchymal transition, in OSCC cells. We found that DZNep reduced the cellular levels of polycomb group proteins (EZH2, SUZ12, BMI1, and RING1A) and the associated trimethylation of Lys27 on histone H3 and monoubiquitination of Lys119 on histone H2A in the poorly differentiated OSCC cell line SAS. Immunocytochemical staining demonstrated that DZNep induced the reorganization of filamentous actin and the membrane localization of E-cadherin associated with cell–cell adhesions. We also found an inhibitory effect of DZNep on cell proliferation using a WST assay. Finally, quantitative RT-PCR analysis demonstrated that genes involved in the aggressive phenotypes (TWIST2, EGFR, ACTA2, TGFB1, WNT5B, and APLIN) were down-regulated, whereas epithelial phenotype genes (CDH1, CLDN4, IVL, and TGM1) were up-regulated in SAS cells treated with DZNep. Collectively, our findings suggest that DZNep reverses the aggressive characteristics of OSCC cells through the dynamic regulation of epithelial plasticity via the reprogramming of gene expression patterns. - Highlights: • DZNep reduced PcG proteins and associated histone modifications in OSCC cells. • DZNep enhanced cell–cell adhesion indicative of epithelial phenotype in OSCC cells. • DZNep suppressed the aggressive phenotype-related gene expression in OSCC cells. • DZNep activated the gene expression of epithelial markers in OSCC cells.

  1. The malignant pleural effusion as a model to investigate intratumoral heterogeneity in lung cancer.

    Directory of Open Access Journals (Sweden)

    Saroj K Basak

    Full Text Available Malignant Pleural Effusions (MPE may be useful as a model to study hierarchical progression of cancer and/or intratumoral heterogeneity. To strengthen the rationale for developing the MPE-model for these purposes, we set out to find evidence for the presence of cancer stem cells (CSC in MPE and demonstrate an ability to sustain intratumoral heterogeneity in MPE-primary cultures. Our studies show that candidate lung CSC-expression signatures (PTEN, OCT4, hTERT, Bmi1, EZH2 and SUZ12 are evident in cell pellets isolated from MPE, and MPE-cytopathology also labels candidate-CSC (CD44, cMET, MDR-1, ALDH subpopulations. Moreover, in primary cultures that use MPE as the source of both tumor cells and the tumor microenvironment (TME, candidate CSC are maintained over time. This allows us to live-sort candidate CSC-fractions from the MPE-tumor mix on the basis of surface markers (CD44, c-MET, uPAR, MDR-1 or differences in xenobiotic metabolism (ALDH. Thus, MPE-primary cultures provide an avenue to extract candidate CSC populations from individual (isogenic MPE-tumors. This will allow us to test whether these cells can be discriminated in functional bioassays. Tumor heterogeneity in MPE-primary cultures is evidenced by variable immunolabeling, differences in colony-morphology, and differences in proliferation rates of cell subpopulations. Collectively, these data justify the ongoing development of the MPE-model for the investigation of intratumoral heterogeneity, tumor-TME interactions, and phenotypic validation of candidate lung CSC, in addition to providing direction for the pre-clinical development of rational therapeutics.

  2. Construction, Cost and Use of an Enriched Uranium, Light-Water Subcritical Assembly; Assemblage Sous-Critique a Uranium Enrichi et Eau Legere; Realisation, Cout et Application; Realizatsiya i stoimost' podkriticheskoj sborki na obogashchennom urane i legkoj vode; Construccion, Coste y Aplicacion de un Conjunto Subcritico de Uranio Enriquecido

    Energy Technology Data Exchange (ETDEWEB)

    Vittoz, B.; Berthet, P.; Gavin, P.; Mandrin, C.; Robert, P.; Thurnheer, J. [Ecole Polytechnique de l' Universite de Lausanne (Switzerland)

    1964-02-15

    ecuaciones de dispersion en teoria de dos grupos. Basta conocer las caracteristicas de un solo plano de barras para prever el flujo neutronico debido a los n planos. Estas caracteristicas se determinan experimentalmente teniendo en cuenta la variacion vertical del flujo neutronico. El estudio se prosigue por evaluacion de la influencia de la distancia entre las banas pertenecientes a un mismo plano. (author) [Russian] Prednaznachennaja dlja jeksperimental'nogo izuchenija reshetok umnozhitelja podkriticheskaja sborka ispol'zuetsja takzhe dlja celej obuchenija. Ustanovka obladaet bol'shimi vozmozhnostjami ispol'zovanija. Izlagajutsja prichiny, po kotorym laboratorija jadernoj tehniki Politehnicheskoj shkoly Lozannskogo universiteta reshila realizovat', naskol'ko jeto vozmozhno, podkriticheskuju sborku svoimi sobstvennymi sredstvami i izbrat' reshetku slaboobogashennyj uran-legkaja voda. Daetsja opisanie principa i realizacii ustrojstv, kotorye pozvoljajut udobno i bystro izmenjat' parametry reshetki i nejtronnogo pitanija: 1. Uranovye sterzhni podveshivajutsja vertikal'no, i kazhdaja tochka podveski imeet dva gradusa svobodnogo hoda bez ogranichenija samogo processa. Jetot princip pozvoljaet, naprimer, var'irovat' posledovatel'no shag reshetki. 2. Nejtronnoe pitanie obespechivaetsja pjat'ju istochnikami, kotorye pomeshajutsja v grafitovom cokole. Rasstojanie jetih istochnikov mozhet takzhe regulirovat'sja posledovatel'nym obrazom. Rassmatrivajutsja problemy bezopasnosti, kotorye sozdaet ustanovka, tem. chto reaktivnost' mozhet sil'no izmenjat'sja ot odnoj konfiguracii k drugoj. Nakonec, privodjatsja rashody po stroitel'stvu i jekspluatacii jetoj podkriticheskoj sborki. S pomoshh'ju podkriticheskoj sborki izuchalas' neperiodicheskaja reshetka, kogda byla predprinjata popytka poluchit' odnorodnyj potok. S jetoj cel'ju ispol'zovana geterogennaja teorija Fajnberga i Horninga. Vnachale rassmatrivaetsja reshetka sterzhnej, raspolozhennyh odinakovym obrazom v n-parallel'nyh planah na

  3. Critical experiments and nuclear calculations - LAMPRE-I; Experiences critiques et calculs nucleaires concernant le LAMPRE-I; Kriticheskie opyty i yadernye raschety - LAMPRE-I; Experimentos criticos u calculos nucleares relativos al LAMPRE-I

    Energy Technology Data Exchange (ETDEWEB)

    Battat, M E [Los Alamos Scientific Laboratory, University of California, Los Alamos, NM (United States)

    1962-03-15

    1 megavatt, aktivnaya zona kotorogo soderzhit rasplavlennyj splav plutoniya i zheleza (90 atomnykh protsentov plutoniya, 10 atomnykh protsentov zheleza pri tochke plavleniya v 410{sup o} TS). Regulirovka reaktivnosti obespechena putem ispol'zovaniya otrazhatelya iz nerzhaveyushchej stali i chetyrekh nikelievykh reguliruyushchikh sterzhnej, raspolozhennykh vne aktivnoj zony. Byli provedeny opyty pri temperaturakh aktivnoj zony v 80, 160 i 480 deg. TS s tem, chtoby opredelit' kriticheskuyu massu i tsennost' otrazhatelya pri kazhdoj iz ehtikh temperatur. Byli izmereny temperaturnyj koehffitsient reaktivnosti, a takzhe tsennost' reguliruyushchikh sterzhnej po izmereniyam perioda. Byli sdelany raschety s ispol'zovaniem metoda S{sub n} dlya resheniya problemy perenosa nejtronov, chtoby opredelit' osnovnye yadernye parametry sistemy. Sravnenie mezhdu raschetnymi i izmerennymi velichinami parametrov takikh kak temperaturnyj koehffitsient, tsennost' reguliruyushchikh ehlementov i kriticheskaya massa predstavlyayut takzhe interes v otsenke nadezhnosti proektnykh raschetov. (author)

  4. Diagnosis by Liver Scintigraphy; Gepatoskennograficheskaya semiotika

    Energy Technology Data Exchange (ETDEWEB)

    Zubovskij, G. [Nauchno-Issledovatel Skij Rentgeno-Radiologicheskij Institut M3 RSfSR, Moskva, SSSR (Russian Federation)

    1969-05-15

    zavisimosti ot konstitucionnyh osobennostej individuuma. Razrabotka osnov gepatoskennograficheskoj semiotiki daet vozmozhnost' uluchshenija diagnosticheskoj jeffektivnosti skennirovanija pri razlichnyh zabolevanijah pecheni. (author)

  5. A Tox21 Approach to Altered Epigenetic Landscapes: Assessing Epigenetic Toxicity Pathways Leading to Altered Gene Expression and Oncogenic Transformation In Vitro

    Directory of Open Access Journals (Sweden)

    Craig L. Parfett

    2017-06-01

    Full Text Available An emerging vision for toxicity testing in the 21st century foresees in vitro assays assuming the leading role in testing for chemical hazards, including testing for carcinogenicity. Toxicity will be determined by monitoring key steps in functionally validated molecular pathways, using tests designed to reveal chemically-induced perturbations that lead to adverse phenotypic endpoints in cultured human cells. Risk assessments would subsequently be derived from the causal in vitro endpoints and concentration vs. effect data extrapolated to human in vivo concentrations. Much direct experimental evidence now shows that disruption of epigenetic processes by chemicals is a carcinogenic mode of action that leads to altered gene functions playing causal roles in cancer initiation and progression. In assessing chemical safety, it would therefore be advantageous to consider an emerging class of carcinogens, the epigenotoxicants, with the ability to change chromatin and/or DNA marks by direct or indirect effects on the activities of enzymes (writers, erasers/editors, remodelers and readers that convey the epigenetic information. Evidence is reviewed supporting a strategy for in vitro hazard identification of carcinogens that induce toxicity through disturbance of functional epigenetic pathways in human somatic cells, leading to inactivated tumour suppressor genes and carcinogenesis. In the context of human cell transformation models, these in vitro pathway measurements ensure high biological relevance to the apical endpoint of cancer. Four causal mechanisms participating in pathways to persistent epigenetic gene silencing were considered: covalent histone modification, nucleosome remodeling, non-coding RNA interaction and DNA methylation. Within these four interacting mechanisms, 25 epigenetic toxicity pathway components (SET1, MLL1, KDM5, G9A, SUV39H1, SETDB1, EZH2, JMJD3, CBX7, CBX8, BMI, SUZ12, HP1, MPP8, DNMT1, DNMT3A, DNMT3B, TET1, MeCP2, SETDB2, BAZ2

  6. Gaziantep Ekonomisinin Ortadoğu Açısından Önemi

    Directory of Open Access Journals (Sweden)

    Recep Ulusoy

    2016-06-01

    Full Text Available Gaziantep tarih boyunca birçok medeniyete ev sahipliği yapmış, Türkiye’nin en önemli sanayi ve ticaret merkezlerinden biridir. Sahip olduğu ticaret potansiyeli ve girişimcilik ruhuyla dünya piyasalarına entegre olmuştur. Türkiye’nin güney sınır komşularıyla yakın ticari ve ekonomik ilişkiler geliştire­rek bölgede sanayi ve ticaret merkezi olmayı başarmıştır. Komşu ülkelerle sınır ticaretini geliştirerek, kendine ve Türkiye ekonomisine önemli katkılar sağlamıştır. Bölgenin en gelişmiş ili olan Gaziantep, Türkiye’nin Ortadoğu’ya açılan en önemli ticaret kapısıdır. Ortadoğu ülkeleriyle geliştirdiği ikili iliş­kiler ekonomik kalkınmayı daha da hızlandırmıştır. Ayrıca Ortadoğu ülkeleri ile Batı ve Asya bloğu arasında mal transferlerinde aracı konumdadır. Ortadoğu bölgesinin sürekli hareketli olması ve bölgede eksik olmayan savaş, ekonomik düzeni bozmakta ve yaşanan olumsuzluklar ihracat ve ithalatı olum­suz etkilemektedir. Gaziantep ekonomisi giderek gelişmekte ve Ortadoğu ihracatına kısmi azalmalarla birlikte katkısı devam etmektedir. Bu makalede kent ile ilgili literatür taranmış, tablo ve grafikler yardımıyla avantaj ve deza­vantajlar analiz edilmiş ve Gaziantep ekonomisinin hem Türkiye hem de Ortadoğu açısından önemi vurgulanmış ve bazı öneriler sunulmuştur.

  7. The First Two Years of Operating Experience of the Kahl Nuclear Power Station; Experience acquise pendant les deux premieres annees de fonctionnement de la centrale nucleaire de Kahl; Opyt pervykh dvukh let ehkspluatatsii atomnoj ehlektrostantsii v Kale; Experiencia adquirida en los primeros cuatro anos de funcionamiento de la central nucleoelectrica de Kahl

    Energy Technology Data Exchange (ETDEWEB)

    Bruchner, H. J. [Aeg-Kernenergieanlagen, Frankfurt-am-Main (Germany); Weckesser, A. [Versuchs-Atomkraftwerk Kahl Gmbh, Kahl (Germany)

    1963-10-15

    , une boucle experimentale destinee a l'etude de la surchauffe nucleaire. (author) [Spanish] La central de Kahl constituye la primera central nucleoelectrica europea de propiedad privada, y funciona en carga desde junio de 1961. Esta equipada con un reactor de agua hi que trabaja en ciclo indirecto por circulacion natural. Su capacidad electrica neta asciende a 15 MW y hasta febrero de 1963 habia producido 140 millones de kWh. La memoria revisara la experiencia adquirida durante su funcionamiento, ante todo con el extenso programa de ensayos sobre el comportamiento transitorio y la exploracion gamma. Presentara datos acerca del resultado que han dado en funcionamiento ciertas partes de la central, tales como el dispositivo de accionamiento de las barras de control, el sistema de purificacion de los gases de escape y la turbina. Una vez terminado el programa de ensayos, la planta se exploto en carga basica durante algun tiempo a fin de reunir datos sobre el rendimiento del combustible en la ptactica. Una vez completada esta fase, se instalara en el reactor de Kahl un circuito experimental de sobrecalentamiento nuclear. (author) [Russian] Atomnaya ehlektrostantsiya v Kale, pervaya v Evrope chastnaya atomnaya ehlektrostantsiya, ehkspluatiruetsya pod nagruzkoj s iyunya 1961 goda. Na ehlektrostantsii ustanovlen reaktor s kipyashchej vodoj, kosvennym tsiklom i estestvennoj tsirkulyatsiej. Chistaya ehlektricheskaya moshchnost' reaktora sostavlyaet 15 mgvt. Do fevralya 1963 goda kolichestvo poluchennoj ehnergii sostavilo 140 mln. kvt.ch. Rassmotren opyt ehkspluatatsii, v chastnosti rasshirennaya programma ispytanij: naprimer,povedenie reaktora pri perekhodnom protsesse i kontrol' gamma-izlucheniya. Budut predstavleny rezul'taty izucheniya ehkspluatatsionnoj kharakteristiki nekotorykh komponentov ustanovki, naprimer sistemy privoda reguliruptsikh sterzhnej, sistemy udaleniya gaza i turbiny. Posle osushchestvleniya ehtoj programmy ispytanij ustanovka v techenie nekotorogo vremeni

  8. Pulsed Source Measurements on a Uranium-Water Subcritical Assembly; Mesures Faites sur un Assemblage Sous- Critique Uranium-Eau Ordinaire a l'Aide d'une Source Pulsee; Izmereniya s pomoshch'yu istochnikov impul'snykh nejtronov na urano-vodnoi podkriticheskoi sborke; Mediciones con Fuentes Pulsantes en un Conjunto Subcritico Uranio-Agua

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, I. H.; Walker, J. [Department of Physics, University of Birmingham, Birmingham (United Kingdom)

    1964-02-15

    reticulado rectificadas con precision; en todos los casos el uranio adopta la forma de barras de 109,8 cm de largo por 3,0 cm de diametro. El combustible se monta horizontalmente, alcanzando el peso de las cargas hasta unas 6 t. Se eliminan, o eligen a voluntad, los armonicos espaciales ubicando convenientemente un pequeno detector de centelleo. Los autores presentan resultados experimentales que indican la relacion de dependencia existente entre la constante de desintegracion y el laplaciano y los comparan con los valores hallados teoricamente. (author) [Russian] Sborka na prirodnom urane i legkoj vode bez otrazhatelja ispol'zuetsja sovmestno s istochnikom impul'snyh nejtronov dlja izmerenija vremeni raspada pri razlichnyh znachenijah laplasiana. Chetyre razlichnyh shaga reshetki na otrezke 3,94 - 5,8 sm byli polucheny putem ispol'zovanija razlichnyh par horosho obrabotannyh plastinok reshetki, v kazhdom sluchae uran byl v vide sterzhnej dlinoj 109,8 i diametrom 3,0 sm. Sterzhni ustanavlivalis' gorizontal'no, ves zagruzok sostavljal priblizitel'no 6 t. Prostranstvennye kolebanija ustranjalis' ili vydeljalis' putem sootvetstvujushhego ustanovlenija nebol'shogo scintilljacionnogo detektora. Budut predstavleny i sravneny s teoreticheskimi dannymi rezul'taty opytov, pokazyvajushhie zavisimost' postojannoj raspada ot laplasiana. (author)

  9. Use of Neutron Irradiations in the Brookhaven Mutations Programme; Irradiation Neutronique dans le Cadre du Programme de Mutations Radioinduites de Brookhaven; Primenenie nejtronnogo izlucheniya v brukkhejvenskoj programme po ispol'zovaniyu mutatsij; La Irradiacion Neutronica en el Marco del Programa de Mutaciones Radioinducidas de Brookhaven

    Energy Technology Data Exchange (ETDEWEB)

    Miksche, J. P.; Shapiro, S. [Biology Department, Brookhaven National Laboratory, Upton, NY (United States)

    1964-03-15

    colaboracion con expertos de Australia, Belgica, Costa Rica, Chile, Dinamarca, Ecuador, Formosa, Grecia, Guatemala, India, Irlanda, Italia, japon, Kenia, Mexico, Paises Bajos, Pakistan, Peru, Filipinas, Rumania, Sudafrica, Tailandia, Venezuela, Alemania Occidental y Yugoeslavia. Los autores presentaran una resefla de los proyectos precitados, deteniendose ante todo en el uso de los neutrones para inducir mutaciones. EBR, por ejemplo, la capacidad de restablecimiento y la manifestacion del efecto oxigeno, principalmente para dosis correspondientes a valores reducidos de la TLE. Si bien esta interpretacion debe considerarse provisional, la distribucion de la dosis en funcion de la TLE proporciona una base para la realizacion de nuevos experimentos sobre la relacion existente entre la EBR y la TLE. (author) [Russian] Programma sotrudnichestva po ispol'zovaniju radiomutacij byla razrabotana v Brukhejvenskoj nacional'noj laboratorii primerno desjat' let nazad, chtoby predostavit' vozmozhnost' rastenievodam i agronomam primenjat' metody obluchenija po programme uluchshenija sortov rastenija. V kachestve ustanovki dlja obluchenija po programme ispol'zovalis' teplovaja kolonna v Brukhejvenskom grafitovom jeksperimental'nom reaktore, rentgenovskij apparat (pikovoe naprjazhenie 250 kv) biologicheskogo otdela jadernoj tehniki, gamma-istochnik moshhnost'ju 12 kjuri v teplicah i istochnik Co{sup 60}, raspolozhennyj v pole ploshhad'ju 13 akrov. V jetoj programme sotrudnichestva na dolju Brukhejvenskoj laboratorii prihoditsja razrabotka oborudovanija metodov i teoreticheskih polozhenij, v to vremja kak rastitel'nyj material i semena predostavljajutsja jekspertami po sel'skomu hozjajstvu, o t vetstvennymi za vyrashhivanie obluchennogo materiala i otbor mutacij. Bo le e 150 uchenyh iz 45 shtatov i Pujerto-Riko uchastvujut v vypolnenii programmy. Nachato takzhe vypolnenie proektov s Avstraliej, Bel'giej, Chili, Ko sta'Rika, Daniej, Jekvadorom, Tajvanem, Greciej, G vatem a loj, Indiej

  10. Comparison of Knolls Atomic Power Laboratory Clean Critical and Subcritical Experiments with Calculations; Etude Comparative des Calculs et des Experiences Critiques Non Empoisonnees et Souscritiques, Faits au Knolls Atomic Power Laboratory; Sravnenie chistykh kriticheskikh i podkriticheskikh opytov v nolle s raschetnymi dannymi; Comparacion de los Resultados Experimentales del Knolls Atomic Power Lamra Tory con los Valores Calculados Teoricamente en Conjuntos Criticos Limpios y Subcriticos

    Energy Technology Data Exchange (ETDEWEB)

    Bach, D. R.; Bistline, J. A.; Bunch, S. I.; Cerbone, R. J.; Feiner, F.; Skolnik, W.; Slovacek, R. E.; Weinstein, S. [Knolls Atomic Tower Laboratory, Schenectady, NY (United States)

    1964-02-15

    - dajushhimi harakteristikami. Mehanicheskie kachestva kriticheskoj sborki takovy, chto kriti- cheskie konfiguracii predstavljajut soboj prostye prjamougol'nye parallelepipedy bez ka- nalov dlja avarijnyh i regulirujushhih sterzhnej. Issledovalsja kriticheskij razmer v sistemah v uslovijah utechki bystyh nejtronov (bez otrazhatelja i {sup s} otrazhatelem) i sravnenija so standartnymi dvuh- i trehrazmernymi gruppo- vymi schetno-reshajushhimi programmami. V celom raschetnye postojannye kritichnosti, vychislen- nye na osnovanii samyh poslednih jadernyh dannyh, priblizitel'no na 3% vyshe. Opisyvaemye opyty s plastinkami ohvatyvali shkalu temperatur, nachinaja ot komnatnoj do 293 Degree-Sign S pri davlenii 84,4 kg/sm{sup 2}. V celjah ustranenija oslozhnenija, svjazannogo s dejstviem regulirujushhih sterzhnej, opredelenie temperatury, pri kotoroj aktivnaja zona dostigala kri- tichnosti, provodilos' pri pochti polnom izvlechenii regulirujushhih sterzhnej. Pri nalichii tekushhej informacii otnositel'no poprechnyh sechenij raschetnaja kritichnost' postojanno vyshe priblizitel'no na 2% na vsem diapazone jeksperimentov. Raschety postojannyh raspada, provedennye metodom ustranenija otravlenija po zakonu l /v s ispol'zovaniem standartnoj gruppovoj diffuzii s uchetom uslovij zavisimosti grupp ot .granicy ukazyvajut na sovpadenie v predelah neskol'kih procentov s izmerennymi postojan- nymi raspada v diapazone ot 100 do 45 000 sek{sup -1}. Sravnenie dannyh izmerenij spektra selektora medlennyh nejtronov s raschetnymi spektrami s pomoshh'ju nedavno poluchennyh funkcij vlijanija svjazannogo vodoroda kak dlja vody, tak i dlja polijetilena svidetel'stvujut o horoshem soglasii, za iskljucheniem vodnyh sistem s vysokimi poglotitel'nymi svojstvami. V poslednem sluchae izmerennye spektry, po- vidimomu, dazhe mjagche, chem raschetnye spektry svobodnyh atomov. (author)

  11. Experimental studies of some of the physical features of beryllium-moderated intermediate reactors; Etude experimentale de quelques particularites physiques des reacteurs a neutrons intermediaires, ralentis au beryllium; Ehksperimental'ny e issledovaniya nekotorykh fizicheskikh osobennostej promezhutochnykh reaktorov s berillievym zamedlitelem; Estudios experimentales de algunas caracteristicas fisicas de los reactores intermedios moderados con berilio

    Energy Technology Data Exchange (ETDEWEB)

    Lejpunskij, A I; Kuznetsov, V A; Artyukhov, G Ya; Mogil' ner, A I; Prokhorov, Yu A; Steklovski, V M; Chernov, L A [Akademiya Nauk, Moskva, Union of Soviet Socialist Republics (Russian Federation)

    1962-03-15

    la evaluacion de la eficacia de los cilindros compensadores giratorios distribuidos en el limite entre el cuerpo y el reflector. (author) [Russian] Doklad posvyashchen obzoru nekotorykh ehksperimen-tal'nykh rezul'tatov, poluchennykh na stende PF-4, prednaznachennom dlya detal'nogo issledovaniya fizicheskikh osobennostej reaktorov, rabotayushchikh na nejtronakh promezhutochnykh ehnergij. Aktivnye zony i otrazhateli razlichnykh kriticheskikh sborok predstavlyali soboj plotnuyu upakovku stal'nykh ili alyuminievykh trub, v kotorykh pomeshchalis' diski iz razlichnykh materialov. Kombinatsiya diskov urana (90%-nogo obogashcheniya) i zamedlyayushchikh materialov v razlichnoj proportsii, a takzhe vvedenie v otrazhatel' zamedlyayushchikh sloev razlichnoj tolshchiny, pozvolilo menyat' spektr nejtronov, proizvodyashchikh delenie, v ochen' shirokikh predelakh. V doklade privedeno opisanie stenda i ego otdel'nykh uzlov. Analiziruetsya sravnitel'naya ehffektivnost' vnutrennego i vneshnego zamedleniya dlya reaktorov s ochen'malym otnosheniem yader zamedlitelya i urana v aktivnoj zone. Ehksperimenty pokazyvayut, chto dazhe v sluchae tolstykh zamedlyayushchikh otrazhatelej maloe razbavlenie urana zamedlitelem (otnoshenie yader berilliya i urana-235 {partial_derivative}Be/{partial_derivative}U{sup 235}{approx_equal}1) privodit k vozrastaniyu kriticheskoj massy. Znachitel'noe mesto v doklade udeleno analizu geterogennykh ehffektov v promezhutochnykh reaktorakh. Pokazano, chto dlya reaktora s {partial_derivative}Be/{partial_derivative}U{sup 235}= 30+40, vysokoobogashchenny j uran v razlichnykh tolshchinakh ot 0,023 g/sm{sup 2} do 32 g/sm{sup 2} okazyvaet odinakovoe vliyanie na reaktiv-nost' sistemy. Analiziruyutsya prichiny, privodyashchie k kompensatsii ehffekta ehkranirovki nejtronnogo potoka tolstymi sloyami urana. V doklade privoditsya interesnyj fakt vozrastaniya ehffektivnosti urana vblizi po- gloshchayushchikh sterzhnej, ehksperimental'n o obnaruzhennyj v sbor kes {partial

  12. The Subcritical Assembly for High-Temperature Use; Assemblage Sous-Critique Pour Emploi a Haute Temperature; K voprosu o podkriticheskoj sborke dlya ispol'zovaniya pri vysokikh temperaturakh; Conjunto Subcritico para Temperatura Elevada

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, Y.; Sekiya, T.; Suita, T. [Osaka University (Japan); Hishida, H.; Hamada, H.; Nagashima, K. [Sumitomo Atomic Energy Industries Group (Japan)

    1964-04-15

    semejantes a los de un pequeflo reactor nuclear. Se estudia la manera de determinar experimentalmente el laplaciano del sistema y se procura encontrar la mejor ubicacion posible para la fuente neutronica pulsante y para los detectores. Ademas, se esta perfeccionando un metodo exclusivo de medicion de la densidad del flujo neutronico a temperatura elevada. Por ultimo, el autor se propone investigar la influencia de esta temperatura elevada sobre los parametros del reactor. (author) [Russian] Podkriticheskie sborki predstavljajut soboj ustanovki s grafitovym zamedlitelem i toplivom v vide prirodnogo urana. Osobennost' konstrukcii takoj ustanovki zakljuchaetsja v nalichii vysokotemperaturnoj oblasti, kotoraja mozhet byt' sozdana v centre sborok aktivnoj zony v nizkotemperaturnoj oblasti i daet vozmozhnost' poluchenija informacii kak dlja vysokotemperaturnogo reaktora s gazovym ohlazhdeniem, tak i dlja neposredstvennogo prevrashhenija jenergii vysokotemperaturnoj gazovoj sredy v jelektrichestvo. Dalee, podkriticheskie sborki predpolagaetsja ispol'zovat' dlja podgotovki studentov starshih kursov. Dannaja sborka byla smontirovana v ob{sup e}me 2 x 2 x 3 m iz grafitovyh blokov v vide kvadratnyh sterzhnej dlinoj 10 sm. Vysokotemperaturnaja oblast' ob{sup e}mom 1 m3 obrazuetsja s pomoshh'ju dzhouleva tepla, v nej mozhet podderzhivat'sja temperatura do 2000 Degree-Sign S. Dlja nizkotemperaturnoj oblasti primenjaetsja toplivo v vide tabletok UO{sub 2}, dlja vysokotemperaturnoj chasti izgotovljajutsja tabletki iz UC{sub 2}. Toplivo pomeshhaetsja vnutri grafitovoj obolochki kvadratnyh sterzhnej. Istochniki Am -Be moshhnost'ju 5 kjuri ustanavlivajutsja pod podstavkoj, raspolozhennoj v nizhnej chasti sborok. S drugoj storony, impul'snye nejtrony inzhektirujutsja v proizvol'noj tochke vnutri sborki. Mishen' v konce rasshiritel'noj trubki uskoritelja bombardiruetsja puchkom dejtronov. Vyhodnaja shina sistemy dzhouleva podogreva ohlazhdaetsja vodoj, a dlja ohlazhdenija vsej poverhnosti stenok

  13. Design and construction of a fast critical facility; Etude et construction d'un ensemble critique a neutrons rapides; Proektirovanie i sooruzhenie kriticheskoj sborki na bystrykh nejtronakh; Proyecto u construccion de un conjunto critico de neutrones rapidos

    Energy Technology Data Exchange (ETDEWEB)

    Kato, W Y; Dates, L R [Argonne National Laboratory, Argonne, IL (United States)

    1962-03-15

    estudiar las propiedades fisicas de los grandes reactores, altamente diluidos, de com- bustible metalico o ceramico, desprovistos de moderador o parcialmente moderados, con cuerpos de hasta 1500 l de volumen. Los autores describen detalladamente el ZPR-VI y analizan los criterios seguidos en el diseno de sus diversos componentes desde el punto de vista de la fisica de reactores. Asimismo, formulan algunas observaciones acerca de los procedimientos de explotacion y manejo del reactor, los peligros que se pueden presentar durante su funcionamiento, las tecnicas experimentales que conviene emplear y los costos de construccion. (author) [Russian] V programme razrabotki ehnergeticheskikh reaktorov na bystrykh nejtronakh kriticheskaya sborka yavlyaetsya ves'ma poleznym sredstvom dlya kontrolirovani ya vychislitel'nykh metodov, proverki sbornikov sechenij nejtronov i polucheniya vsekh parametrov reaktornoj fiziki, neobkhodimykh dlya proektirovaniya yadernoj ehnergeticheskoj sistemy. 'Poskol'ku ona yavlyaetsya prezhde vsego fizicheskoj sistemoj, proektirovanie kriticheskoj sborki stavit samo po sebe ryad trudnykh problem, ne vstrechayushchikhsya pri proektirovanii ehnergeticheskogo reaktora. Krome obychnykh voprosov, svyazannykh s mestoraspolozheniem , obolochkoj reaktora, raschetom aktivnoj zony i kontrol'no-izmeritel'nym i priborami, voznikayut takie problemy, kak dostizhenie vysokoj stepeni gibkosti, sovmestimoj s bezopasnost'yu, opredelenie razmerov i tipa ustanovki, udovletvoryayushchi kh trebovaniyam ehksperimental'noj fiziki, opredelenie chisla i razmeshcheniya reguliruyushchikh i avarijnykh sterzhnej, svodyashchikh k minimumu posledstviya vozmushchenij, i spetsifikatsiya vosproizvodimost i reguliruyushchikh sterzhnej i drugikh podvizhnykh komponentov s tem, chtoby obespechit' toch- nost', neobkhodimuyu pri izmereniyakh reaktivnosti. EHto lish' nekotorye iz problem, kotorye obsuzhdayutsya v nastoyashchem doklade, osnovannom na poslednem ehksperimente v Argonnskoj natsional

  14. Description of Radiation Sources Installed at the French Atomic Energy Commissariat; Description de sources de rayonnement installees au commissariat a l'energie atomique; Opisanie istochnikov oblucheniya, nakhodyashchikhsya v frantsuzskom komissariate po atomnoj ehnergii; Descripcion de las fuentes de radiaciones instaladas en el commissariat a l'energie

    Energy Technology Data Exchange (ETDEWEB)

    Leveque, P

    1960-07-15

    organicas, ya que el flujo epitermico y rapido provoca la activacion de la mayor parte de los productos sometidos a la irradiacion. A continuacion, el autor describe las instalaciones del Centro de Aplicaciones Atomicas de Lyon creado en las proximidades de dicha ciudad por un grupo de industriales. Este Centro, que segun esta previsto comenzara a funcionar en 1960, tendra un caracter semi-industrial (para comenzar, una fuente de cobalto-60 de 3 000 curies y mas adelante, otra de 40 000 curies) y permitira realizar operaciones de irradiacion de una manera continua. (author) [Russian] Prezhde vsego avtor daet opisanie chetyrekh ustanovok, nakhodyashchikhsya v yadernom issledovatel'skom tsentre v Sakleh. - Laboratornyj istochnik v 600 kyuri kobal'ta-60; ispol'zuemyj pribor yavlyaetsya prostym i bezopasnym, no ne daet vozmozhnosti izmenyat' potok gamma-luchej. - Pribor, sostoyashchij iz semi istochnikov kobal'ta-60 (samyj moshchnyj v 1000 kyuri), ustanovlennykh v betonnoj kamere; pnevmaticheski j pribor pozvolyaet ustanovit' odin ili neskol'ko neobkhodimykh istochnikov v rabochem polozhenii. - Kamera vmeshchaet 100 sterzhnej yadernogo goryuchego ot novogo reaktora EL3; chast' ehtoj kamery prisposoblena dlya okhlazhdeniya, chto pozvolit proizvodit' opyty nad konservatsiej pishchevykh produktov dejstviem oblucheniya. - Vertikal'nye kanaly reaktora EL 2, tak nazyvaemye ''okna khimika''; kogda ehti kanaly obernuty kadmievoj fol'goj, dostigaemyj potok gamma-luchej perekhodit so 100000 na 200000 rentgeno/chasov, no oni mogut sluzhit' tol'ko dlya oblucheniya organicheskikh materialov, tak kak imeetsya aktivatsiya bol'shej chasti obluchaemykh produktov pri pomoshchi bystrogo ehpitermicheskogo potoka. Zatem avtor daet opisanie pribora, ustanovlennogo v Lionskom tsentre po ispol'zovaniyu atomov, postroennogo okolo Liona gruppoj promyshlennikov. EHtot pribor, pusk v ehkspluatatsiyu kotorogo predusmotren na nachalo 1960 goda, budet nosit' polupromyshlennyj kharakter (istochnik kobal'ta-60

  15. Technical and Administrative Considerations in the Management of Radioactive Wastes; Considerations Techniques et Administratives Relatives au Traitement des Dechets Radioactifs; 0422 0415 0425 041d 0418 0427 0415 0421 041a 0414 ; Aspectos Tecnicos y Administrativos de la Manipulacion de Desechos Radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Wolman, Abel [Johns Hopkins University, Baltimore, MD (United States); Division of Reactor Development, U.S. Atomic Energy Commission, Washington, DC (United States); Lieberman, Joseph A. [Environmental and Sanitary Engineering Branch, Division of Reactor Development, U.S. Atomic Energy Commission, Washington, DC (United States)

    1960-07-01

    entre la localizacion de la planta y la situacion de la zona de evacuacion. Ademas, se exponen otras consideraciones relacionadas con la manipulacion de desechos radiactivos, tales como la eleccion de emplazamientos y los problemas de transporte. (author) [Russian] Cel' nastojashhego doklada sostoit v rassmotrenii tehnicheskih i administrativnyh aspektov obrashhenija s radioaktivnymi othodami v svete imejushhegosja u nas opyta i znanij i uchete jetogo obsuzhdenija dlja vozmozhnyh budushhih trebovanij v oblasti sootvetstvujushhego tehnicheskogo, juridicheskogo i administrativnogo kontrolja nad radioaktivnymi othodami v rezul'tate ispol'zovanija jenergii. Pervonachal'no razlichnye vidy. radioaktivnyh othodov razbivajutsja na obshhie kategorii dlja togo, chtoby podcherknut', chto mnogochislennye stojashhie pered nami problemy obrashhenija s othodami ne poddajutsja edinichnomu v svoem rode resheniju. Kratko summiruetsja rol' specificheskoj okruzhajushhej sredy v praktike obrashhenija s othodami i opredeljajutsja osnovnye podhody (''rastvorenie i dispersija'' i ''koncentracija i soderzhanie'') k osushhestvleniju kontrolja nad othodami. Provoditsja razlichie mezhdu osnovnymi standartami po zashhite ot radiacii i operativnym ili proizvodstvennym kriterijami, kotorye dolzhny byt' ustanovleny v svjazi s operacijami po kontrolju nad othodami dlja obespechenija udovletvorenija osnovnyh standartov. Rassmatrivaetsja razrabotka standartov i kriterija i ih primenenie dlja rasprostranenija pravil po ohrane zdorov'ja i tehniki bezopasnosti i juridicheskoj i administrativnoj procedury. V jetoj svjazi predlagaetsja maksimal'noe ispol'zovanie sushhestvujushhego zakonodatel'stva i administrativnoj procedury v sushhestvujushhih uchrezhdenijah na razlichnyh urovnjah upravlenija, vygodnyh kak s administrativnoj tochki zrenija, tak i s tochki zrenija obshhestvennyh otnoshenij. Hotja obshhie rashody na obrashhenie s radioaktivnymi otho'dami i ih udalenie javljajutsja sushhestvennymi, rashody na

  16. Technical Developments in the USAEC Process Radiation Development Program; Etudes technologiques dans le cadre du programme de mise au point d'applications industrielles des rayonnements de la CEA-EU; Issledovaniya v oblasti promyshlennogo primeneniya izluchenij, vkhodyashchie v programmu komissii po atomnoj ehnergii USAEC; Progresos tecnicos en el programa de la USAEC para el fomento de la irradiacion industrial

    Energy Technology Data Exchange (ETDEWEB)

    Machurek, J. E.; Stein, M. H. [Division of Isotopes Development, USAEC, Washington, DC (United States)

    1963-11-15

    ispol'zovanie ioniziruyushchikh izluchenij v promyshlennosti. Provedeno chetyrnadtsat' takikh issledovanij, rezul'taty nekotorykh iz nikh izlozheny v obshchikh chertakh v dannoj rabote, ostal'nye izlagayutsya bolee podrobno - v drugikh stat'yakh trudov. Temy issledovanij vklyuchayut: 1. Prigotovlenie kombinatsij derevo-plastik, ispol'zuya gamma-izluchenie dlya indutsirovaniya polimerizatsii. 2. Ispol'zovanie beta-izlucheniya produktov deleniya dlya gidrogenizatsii uglya, i ego produktov s tsel'yu polucheniya zhidkogo uglevodorodnogo topliva. 3. Poluchenie poluprovodnikovykh priborov s formirovaniem zadannogo prostranstvennogo raspredeleniya primesej v zavisimosti ot legirovaniya putem nejtronnykh prevrashchenij. 4. Vyzvannaya izlucheniem polimerizatsiya ehtilena i sopolimerov. 5. Osnovnye issledovaniya mekhanizmov i kinetiki reaktsij, vyzvannykh izlucheniem. 6. Radiatsionno-khimicheskie protsessy pri ftorirovanii razlichnykh aromaticheskikh soedinenij. 7. Ispol'zovanie polifunktsional'nykh monomerov dlya intensifikatsii radiatsionnogo sshivaniya poliehtilena, polipropilena, poliizobutilena i atsetattsellyulozy. 8. Vliyanie nabukhaniya, deformatsii i temperatury na fizicheskie i khimicheskie svojstva polimerov, poluchennykh s pomoshch'yu radiatsii. 9. Vliyanie strukturnykh faktorov na radiatsionnye izmeneniya v polimerakh, privodyashchie k graftsopolimerizatsii. 10. Ispol'zovanie yadernykh izluchenij dlya modifikatstsii tekstil'nykh materialov. 11. Reaktsii, vyzvannye izlucheniem kriptona-85. 12. Podgotovka ''Spravochnika po radiatsii''. 13. Ispol'zovanie metalloorganicheskoj svyazi dlya gamma-dozimetrii pri bol'shikh moshchnostyakh dozy. 14. Razrabotka dozimetra s solnechnym ehlementom. (author)

  17. Review of the {sup 60}Co Source. Development Program at Brookhaven National Laboratory; Le Programme de Mise au Point des Sources au {sup 60}Co au Laboratoire National de Brookhaven; Obzor programmy po razrabotke istochnikov {sup 60}Co v brukkhejvenskoj natsional'noj laboratorii; El Programa de Preparacion de Fuentes de {sup 60}Co del Laboratorio Nacional de Brookhaven

    Energy Technology Data Exchange (ETDEWEB)

    Kuhl, O. A. [Brookhaven National Laboratory, Upton, NY (United States)

    1966-11-15

    jenergii SShA Brukhejvenskaja nacional'naja laboratorija(BNL) pristupila k razrabotke istochnikov izluchenij. Jeti istochniki byli v osnovnom bol'shie trubki i ploskie plastinki. Pervonachal'no oni prednaznachalis' dlja issledovanij v BNL. Pozdnee drugie uchrezhdenija poluchili razreshenie ispol'zovat' obluchateli, prednaznachennye dlja jetih istochnikov. Po mere povyshenija interesa kombinirovannye ustanovki, vkljuchajushhie istochnik i obluchatel', predostavljalis' drugim issledovateljam. Byli razrabotany kontejnery dlja transportirovki istochnikov i skonstruirovany nebol'shie ''gorjachie'' kamery i napolnennye vodoj bassejny dlja ispol'zovanija jetih istochnikov. Obsuzhdajutsja metody dozimetrii, opredelenie radioaktivnosti v kjuri i konstrukcija obluchatelja dlja jetih istochnikov. V bol'shinstve sluchaev vo vremja provedenija issledovanij jekonomicheskie aspekty ne imeli znachenija; odnako v svjazi s tendenciej k krupnomasshtabnoj radiacionnoj obrabotke v obla Inverted-Question-Mark tjax pishhevyh produktov, himikatov i medicinskih materialov neobhodimo budet tshhatel'no izuchit' tehnicheskie i jekonomicheskie aspekty konstrukcii istochnika. Razrabotka standartnyh istochnikov Brukhejvenskoj nacional'noj laboratorii ''Mark I'' i ''Mark I{sup ,} kotorye' uzhe ispol'zujutsja v rjade ustanovok, prizvana udovletvorit' jetim vazhnym trebovanijam. Istochniki ''Mark Ij i 'Mark II' vzaimozamenjaemy. Konstrukcija istochnika 'Mark II' uluchshena za schet metallurgicheskogo soedinenija vnutrennej obolochki s kobal'tovym serdechnikom. V nastojashhee vremja vpervye mozhno povtorno aktivirovat' jeti istochniki posle nekotorogo ispol'zovanija. Otdel'nye polosy dovodjatsja do trebuemyh razmerov s tem, chtoby ih mozhno bylo legko prikrepit' k plastinkam razlichnogo razmera i formy. Opisyvajutsja teoreticheskoe obosnovanie konstrukcii, metody izgotovlenija i procedury ispytanija, a takzhe analiz istochnika i opredelenie radioaktivnosti v kjuri. ''Proizvodjatsja ''sravnenija s drugimi

  18. Fission-Product Separation as a Final Solution to the Problem of Storing Highly Radioactive Waste; La Separation des Produits de Fission Comme Solution Definitive du Stockage des Dechets Fortement Radioactifs; 0412 042b 0414 ; La Separacion de los Productos de Fision Como Solucion Definitiva del Problema del Almacenamiento de los Desechos de Elevada Radiactividad

    Energy Technology Data Exchange (ETDEWEB)

    Raggenbass, A.; Lefevre, J. [Centre d' Etudes Nucleaires, Saclay (France)

    1963-02-15

    incorporacion de los desechos a masas vitreas. (author) [Russian] V 1955 godu na Zhenevskoj konferencii Gljukauf sformuliroval gipotezu o tom, chto okonchatel'noe reshenie problemy udalenija aktivnyh rastvorov, soderzhashhih produkty delenija, mohet byt' najdeno putem vydelenija cejeija-137 i stroncija-90 s kojefficientom ochistki porjadka menee 10{sup 4}, chto pozvolilo by posle vyderzhki 10-20 let svobodno udaljat' jeti othody posle sootvetstvujushhej pererabotki. Doklad presleduet cel' snova vernut'sja k jetomu voprosu v 1963 godu. Uspehi, dostignutye v metodah vydelenija cezija i stroncija, pozvoljaet poluchit' kojefficient ochistki porjadka 10{sup 4} v uslovijah promyshlennoj jekspluatacii ustanovki. Dlja cejeija-137 javljaetsja perspektivnym osazhdenie fosforvo.i'framatnoj kislotoj, obmen s ammonijnymi soljami geteropolikisloty, fiksacija fosfatom cirkonija, a dlja stroncija-90 - oksalatnoe osazhdenie, jekstrakcija di-2- jetilgeksilfosfornoj kislotoj, obmen s razlichnymi soljami, vkljuchaja sul'fat stroncija i dr. Jeti uspehi v oblasti himii vmeste s uspehami v oblasti promyshlennoj pererabotki jefljuentov sdelali vozmozhnym s tehnicheskoj tochki zrenija podtverdit' gipotezu Gljukaufa. Narjadu s jetim, razrabotka metodov ispol'zovanija bol'shih kolichestv produktov delenija, osobenno v sootvetstvii s programmami SNAP, chastichno opravdyvaet kapitalovlozhenija za schet prodazhi proizvodimoj produkcii. Ochevidno, chto ispol'zovanie ogneupornyh istochnikov, ustojchivyh k agressivnym vozdejstvijam vneshnej sredy, predstavljaet soboj primer, kotoryj naibolee otvechaet trebovanijam hranenija othodov, ves'ma opasnyh v techenie prodolzhitel'nogo perioda. My schitaem takzhe, chto s tehnicheskoj i psihologicheskoj tochek zrenija koncentrirovannye istochniki, pokrytye zashhitnoj obolochkoj, naibolee nadezhny kak sredstva hranenija radioaktivnyh othodov. Sravnenie jetogo metoda s metodom vvedenija radioaktivnosti v stekla zasluzhivaet bolee polnogo i glubokogo rassmotrenija. (author)

  19. The Permanent Disposal of Highly Radioactive Wastes by Incorporation into Glass; Elimination Permanente de Dechets Hautement Radioactifs par Incorporation dans le Verre; 041e 041a 041e 041d 0427 0414 ; La Evacuacion Permanente de Desechos de Elevada Radiactividad Incorporandolos en Vidrio

    Energy Technology Data Exchange (ETDEWEB)

    Watson, L. C.; Aikin, A. M.; Bancroft, A. I. [Atomic Energy of Canada Ltd. (Canada)

    1960-07-01

    tratamiento quimico. Se ha, ensayado el sistema produciendo un vidrio que contiene hasta 50 curies de productos de fision de cinco a seis anos de edad por kilogramo. El procedimiento es intermitente y trabaja en partidas de cuatro kilogramos. Se ha demostrado que los productos de fision pueden ser incorporados al vidrio en forma eficaz y segura. El estudio de los muchos problemas que encierra el almacenaje permanente o la evacuacion del vidrio de alto nivel radiactivo ha llevado a la conclusion de que deberia ser enterrado en el suelo o almacenado en depositos subterraneos artificiales. En estas condiciones es siempre posible, caso de que sea necesario, proceder a un nuevo control de los desechos. Si la evacuacion se efectua enterrando los desechos, los productos de fision se liberan sobre todo mediante lixiviacion por las aguas subterraneas. Asi pues, es importante saber la velocidad con que los productos de fision se difundiran mediante este procedimiento. Se ha reunido buen numero de datos sobre la lixiviacion por agua en el laboratorio, y se ha encontrado que la velocidad de difusion depende de la composicion del vidrio. En todas las composiciones que se ensayaron las mediciones demostraron que la velocidad de lixiviacion de los productos de fision contenidos en el vidrio disminuye con el tiempo. Despues de varios meses de inmersion en agua la velocidad de difusion para vidrios de diversas composiciones era de 10{sup -4} por ciento aproximadamente por ano para una semiesfera de vidrio de dos kilogramos de peso. Los datos obtenidos han sido empleados para calcular la velocidad con que se difunden los productos de fision incorporados a vidrio en las grandes cantidades en que se acumularan como resultado del funcionamiento de los reactores generadores de energia. (author) [Russian] V Chok River prodolzhaetsja razrabotka processa zakljuchenija v steklo vysokoradioaktivnyh othodov, poluchaemyh v rezul'tate operacij po himicheskoj pererabotke, dlja okonchatel'nogo ih udalenija

  20. Issuing of Regulations on the Clearance of Irradiated Food Products on the Basis of Foreign Petitions; Promulgation d'un Reglement Regissant l'Autorisation de Commercialiser des Denrees Alimentaires Irradiees, sur la Base de Demandes Fondees sur des Donnees Elaborees a l'Etranger; Protsedura polucheniya razreshenij na prodazhu obluchennykh pishchevykh produktov na baze inostrannykh khodatajstv; Autorizacion del Consumo de Productos Alimenticios Irradiados, Sobre la Base de Investigaciones Realizadas en el Extranjero

    Energy Technology Data Exchange (ETDEWEB)

    Foa, E.; Eisenberg, E.; Kahan, R. S.; Lapidot, M. [Soreq Nuclear Research Centre, Yavne (Israel)

    1966-11-15

    processom obluchenija i raspredelenija obluchennyh produktov, primenenie sootvetstvujushhih zakonov jli razrabotka novyh v sluchae ih otsutstvija. Bol'shaja chast' zakonodatel'stv, sushhestvujushhih v nastojashhee vremja, trebuet absoljutno podtverzhdenija prigodnosti upotreblenija teh ili inyh pishhevyh produktov v pishhu, prezhde chem budet polucheno razreshenie na ih obluchenija i sbyt. Odnako takoe dokazatel'stvo prigodnosti pishhevyh produktov ne po sredstvam malym i razvivajushhimsja stranam, t.e. tem stranam, kotorye mogli by poluchit' naibol'shuju vygodu ot vnedrenija metodov obluchenija v promyshlennyh masshtabah, tak kak jeto uvelichivalo by kolichestvo mestnyh pishhevyh produktov dlja vnutrennego potreblenija i jeksporta. V kachestve jeksperimenta v Ministerstvo zdravoohranenija Izrailja bylo napravleno 24 fevralja 1966 goda hodatajstvo o razreshenii vypustit' na rynok belyj kartofel', obluchennyj s cel'ju predotvrashhenija prorastanija. Hodatajstvo bylo sostavleno ne na osnovanii issledovatel'skih rabot v Izraile, a na osnovanii dannyh, opublikovannyh za granicej. V nem soderzhalas' pros'ba prinjat' v kachestve dokazatel'stv opyty, odobrennye drugimi pravitel'stvami. Vskore budet predstavleno analogichnoe hodatajstvo otnositel'no sbyta obluchennogo luka. V sluchae uspeha, jeta procedura mozhet byt' ispol'zovana i drugimi stranami, chto oblegchilo by podpisanie mezhdunarodnyh torgovyh soglashenij. Jeto sposobstvovalo by bystrejshemu vnedreniju metodov obluchenija dlja sohranenija pishhevyh produktov v teh stranah, gde jeto mozhet prinesti jekonomicheskuju vygodu. (author)

  1. MASURCA, a Fast-Neutron Critical Mock-Up: Operation and Uses; MASURCA. Maquette Critique a Neutrons Rapides. Description Fonctionnelle et Obiectifs; ''MAZURKA'' - kriticheskaya model' na bystrykh nejtronakh. funktsional'noe opisanie i tseli; Descripcion Funcional y Objetivos de la Maqueta Critica de Neutrones Rapidos 'MASURCA '

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, A. P.; Storrer, F.; Vendryes, G. [Association CEA-EURATOM, Cadarache (France); Tavernier, G.; Van Dievoet, J. [Societe Belgo-Nucleaire, Bruxelles (Belgium)

    1964-02-15

    . (author) [Russian] V nastojashhee vremja v Centre jadernyh issledovanij Kadarash v ramkah Associacii Evratom -KAJe konstruiruetsja kriticheskij maket na bystryh nejtro- nah pod nazvaniem {sup M}azurka{sup .} Jeta ustanovka obladaet bol'shimi vozmozhnostjami dlja pro- vedenija jeksperimentov i prednaznachena glavnym obrazom dlja provedenija issledovanij na krupnyh plutonievyh kriticheskih sborkah bez zamedlitelej s otnositel'no podvizhnym nej- tronnym spektrom. Izlagajutsja celi issledovanij, dlja osushhestvlenija kotoryh podobnaja ustanovka dolzhna otvechat' opredelennym uslovijam. Prezhde vsego ona dolzhna imet' bol'shuju gibkost' v ispol'zovanii i obespechivat' pochti absoljutnuju bezopasnost' v rabote. Problema bezopasnosti byla reshena putem: 1 .Issledovanija prisushhej ustanovke bezopasnosti; jelementy, imitirujushhie toplivo, pozvolili poluchit': a) kojefficient otricatel'noj reaktivnosti v rezul'tate kumu- ljativnogo prodol'nogo rasshirenija jetih jelementov; b) otricatel'nyj kojefficient Dopplera. 2 .Ispol'zovanija puchka avarijnyh upravljajushhih sterzhnej i kompensirujushhih sterzhnej; jeti sterzhni mogut razmeshhat'sja na reshetke s kvadratom 30 sm. 3.Primenenija germeticheskoj kamery s argonom na sluchaj pozhara. 4 . Strogogo administrativnogo kontrolja. Vybor metallicheskogo splava uran -plutonij -zhelezo v kachestve osnovnogo jelementa imitirovanija topliva zastavljaet predusmatrivat' ohlazhdenie krupnyh kriticheskih sborok v ustanovke. Natrij v kachestve zhidkogo ohladitelja dlja modeliruemyh reaktorov predstavlen natrie- vymi palochkami v obolochke iz nerzhavejushhej stali. Jeta ustanovka predstavljaet soboj vertikal'no-monoblokovyj tip. Takoj vybor ob{sup -} jasnjaetsja stremleniem poluchit' maksimal'nyj ob{sup e}m aktivnyh zon, kotoryj bylo predusmot- reno modelirovat' (porjadka 5000 l). Imitirujushhie jelementy imejut formu prjamoj prizmy s kvadratnym osnovaniem (krome toplivnyh jelementov s krugovoj osnovoj) s vneshnej storonoj (ili diametrom) 12,7 mm

  2. Fabrication and Testing of Prototype APM-Clad UO{sub 2} Fuel Elements; Fabrication et essai de prototypes de cartouches de combustible en bioxyde d'uranium gaine d'aluminium (APM); Izgotovlenie i ispytanie prototipa toplivnykh ehlementov na osnove UO{sub 2} s obolochkoj iz alyuminiya metodom poroshkovoj metallurgii; Elaboracion y ensayo de elementos combustibles prototipo de UO{sub 2} con revestimiento de aluminio sinterizado

    Energy Technology Data Exchange (ETDEWEB)

    Ballif, III, J. L.; Friske, W. H.; Gordon, R. B. [Atomics International, Canoga Park, California (United States)

    1963-11-15

    los elementos combustibles se extrajeron del reactor a raiz de problemas suscitados por el instrumental utilizado para los ensayos. Los tres elementos restantes continuaban en el reactor. Todos los resultados de los experimentos realizados hasta la fecha parecen indicar que el sistema de combustible PMA-UO{sub 2} permitira alcanzar los objetivos fijados para el programa relativo al reactor POPR. (author) [Russian] V podderzhku Programmy prototipov organicheskikh ehnergoreaktorov (POPR) moshchnost'yu 50 mgvt (ehl.) byla provedena obshirnaya rabota po razrabotke poroshkovoj metallurgiej alyuminievykh materialov (APM) v kachestve obolochek dlya topliva iz UO{sub 2} . Kak chast' ehtoj raboty byli issledovany ehvteticheskoe soedinenie, svarke v styk oplavleniem i kholodnaya svarka. Kolduehlla pod davleniem kak metody dlya soedineniya stykov pri sborke toplivnykh ehlementov. Vibratsionnoe uplotnenie izuchalos' kak sredstvo zapolneniya trubok APM dvuokis'yu urana. Opyty vne reaktora provodilis' dlya.ogo, chtoby poluchit' informatsiyu o svomestimosti APM - UO{sub 2} . Ehta rabota pokazala, chto pri sushchestvuyushchikh usloviyakh ehvteticheskoe soedinenie yavlyaetsya naibolee podkhodyashchim sposobom dlya soedineniya stykov; vibratsionnoe uplotnenie davalo plotnost' topliva v predelakh ot 80 do 88% teoreticheskoj plotnosti, i ne nablyudalos' vzaimodejstvie APM -UO{sub 2} v diapazone ehkspluatatsionnykh temperatur POPR (temperatura poverkhnosti razdela toplivo - obolochka maksimum 850{sup o}F). V rezul'tate ehtoj raboty bylo izgotovleno 5 prototipov UO{sub 2}-APM toplivnykh ehlementov s tsel'yu ispytaniya na opytnom reaktore s organicheskim zamedlitelem. Kazhdyj ehlement sostoyal iz 24 ili 25 toplivnykh sterzhnej v obolochke iz APM i sgruppirovannykh v sistemu 5 x 5 v stal'noj korobke, pokrytoj nikelem, ili toplivnoj korobke ieh APM. Dlya togo, chtoby uvelichit' poverkhnost' ehlementa i tem samym znachitel'no uluchshit' teploperedachu, izgotovlennaya ehkstruziej obolochka ieh

  3. The Technique and Dosimetry of Pituitary Implantation Using Sources of Y{sup 90}; Technique et Dosimetrie de l'Implantation de Sources d'Yttrium-90 dans l'Hypophyse; ДОЗИМЕТРИЯ ИМПЛАНТИРОВАННЫХ В ГИПОФИЗ ИГЛ ИТТРИЯ-90; Dosimetria de la Implantacion de Fuentes de {sup 90}Y en la Hipofisis

    Energy Technology Data Exchange (ETDEWEB)

    Duggan, Mary H.; Jones, E.; Mallard, J. R. [Department of Physics, Hammersmith Hospital, London (United Kingdom); Joplin, G. F. [Department of Medicine, Postgraduate Medical School, London (United Kingdom)

    1963-03-15

    de implantacion consiste en elegir un tamano y una actividad de la fuente adaptados a las dimensiones de la glandula en cuestion. De esta manera, se procura que el procedimiento sea uniforme en todas las implantaciones. La forma de la glandula y el acceso a ella son tales que la mejor manera de lograr su destruccion completa es implantar dos fuentes, consistentes en varillas de Y{sub 2}O{sub 3} sintetizado (de 1 mm de diametro y de longitud adaptada a las dimensiones de la glandula). La actividad de la varilla se elige tambien convenientemente; en los casos caracteristicos esta comprendida entre 2 y 3 me. Los autores han encontrado experimentalmente la relacion entre la dosis de irradiacion por una parte y la geometria y la actividad por otra. Como absorbedor equivalente al tejido, utilizaron cera Mix D; como detector, una pelicula y como patron, una fuente calibrada de {sup 90}Sr ( que se desintegra formando {sup 90}Y). La memoria examina la validez de este procedimiento. Este trabajo permitio comprobar que la necrosis y la ablacion de la hipofisis requieren dosis que oscitan entre 100 000 y 200 000 rad. (author) [Russian] Udalenija gipofiza putem implantacii ittrievoj igly nahodit vse vozrastajushhee primenenie pri lechenii raka grudnoj i predstatel'noj zhelez,tak zhe kak pri lechenii diabeticheskoj retinopatii, bolezni Kushinga, akromegalii i, vozmozhno, jekzoftal'ma pri bazedovoj bolezni. IttriJ-90 javljaetsja naibolee podhodjashhim izotopom, kogda trebuetsja polnoe udalenie zhelezy, tak kejs on ispuskaet tol'ko beta-chasticy, maksimal'nyj radius dejstvija kotoryh (7 mm) soizmerim o razmerami zhelez. Implantacija v zhelezu sterzhnej standartnoj aktivnosti, nezavisimo ot ih velichiny, nedopustima iz-za standartnogo urovnja dozy, vvodimoj v zhelezy, togda kak cel'ju metoda implantacii javljaetsja vozmozhnost' vybora velichiny i aktivnosti istochnika sootvetstvenno razmeram rassmatrivaemoj zhelezy. Takim obrazom kachestvo metodiki mozhet sovershenstvovat'sja ot

  4. Non-Destructive Testing Methods Applied to Multi-Finned SAP Tubing for Nuclear-Fuel Elements; Essais Non Destructifs de Gaines a Ailettes, en Poudre d'Aluminium Frittee, pour Elements Combustibles; Nedestruktivnye metody ispytaniya rebristykh trub iz spechennogo alyuminikiog'o poroshka dlya yadernykh toplivnykh ehlementov; Metodos de Ensayo No Destructivo Aplicados a Tubos de SAP con Aletas Multiples Destinados a Elementos Combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Lund, S. A. [Danish Central Welding Institution, Copenhagen (Denmark); Knudsen, P. [Danish Atomic Energy Commission, Research Establishment, Risoe (Denmark)

    1965-09-15

    corrientes de Foucault. (author) [Russian] Komissija po atomnoj jenergii Danii predprinjala izuchenie jenergeticheskogo reaktora s organicheskim teplonositelem i tjazhelovodnym zamedlitelem. Toplivnym jelementom dlja reaktora javljaetsja puchok iz 19 sterzhnej; toplivnyj sterzhen' soderzhit spechennye tabletki iz dvuokisi urana v dvuhmetrovoj trube iz spechennogo aljuminievogo poroshka. Truby dolzhny byt' ochen' horoshego kachestva, chtoby obespechit' optimal'nye uslovija perenosa tepla i sohranenija celostnosti toplivnyh jelementov vo vremja jekspluatacii reaktora. Dva primera otnositel'no konstrukcii trub svidetel'stvujut ob ochen' nebol'shih razmernyh dopuskah. Dlja obespechenija sootvetstvujushhego kachestva trub razrabotan strogij kontrol' v znachitel'noj stepeni osnovannyj na nedestruktivnyh metodah. Privoditsja opisanie jetih metodov, razrabotannyh dlja izmerenija tolshhiny stenok i diametrov i dlja obnaruzhenija defektov. Slozhnoe poperechnoe sechenie 24-rebernoj truby ne pozvoljaet primenjat' ul'trazvukovye metody ili metody vihrevyh tokov dlja izmerenija tolshhiny stenok. Pojetomu razrabotan special'nyj kontrol'no-izmeritel'nyj pribor, registrirujushhij beta-izluchenie, osnovannyj na principe oslablenija beta-izluchenija, poluchaemogo ot istochnika stroncija-90, pomeshhennogo vnutri truby. Metod ul'trazvukovogo rezonansa pri pogruzhenii primenjaetsja dlja postojannoj registracii tolshhiny stenok bolee prostyh konstrukcij 12-rebernyh trub. Vnutrennij i vneshnij (mezhdu granjami reber) diametry postojanno registrirujutsja bystrodejstvujushhimi sistemami vozduhomerov. Defekty obnaruzhivajut s pomoshh'ju ul'trazvuka metodom impul's-jeho i metodom vihrevyh tokov. Metodom ul'trazvuka mozhno legko obnaruzhivat' poperechnye no ne prodol'nye treshhiny. Pojetomu, krome proverki ul'trazvukom, primenjaetsja ispytanie vihrevymi tokami. (author)

  5. Control Methods Used in the Department of Metallurgy for Structure and Fuel Elements; Methodes de Controle Utilisees au Departement de Metallurgie pour les Elements de Structure et les Elements Combustibles; Metody kontrolya struktury toplivnykh ehlementov v departamente metallurgii; Metodos de Control Utilizados en el Departamento de Metalurgia para los Elementos Estructurales y Combustibles

    Energy Technology Data Exchange (ETDEWEB)

    Destribats, Marie-Therese; Allain, C.; Prot, A.; Thome, P. [Centre d' Etudes Nucleaires de Saclay (France)

    1965-09-15

    metodos se han desarrollado con miras a su utilizacion industrial. Algunos de ellos se aplican ya corrientemente durante la fabricacion; otros se utilizaran proximamente y el resto es susceptible de aplicacion a mas largo plazo. (author) [Russian] Nachatoe v KAJe izuchenie razlichnyh tipov reaktorov privelo k ispol'zovaniju i razrabotke mnogih metodov nedestruktivnogo kontrolja razlichnyh materialov, v chastnosti radiografii, gammagrafii, ul'trazvukovyh voln i metoda tokov Fuko. Nizhe govoritsja o kontrole v processe stroitel'stva reaktorov sistemy EDF (grafit- gaz), EL4 (tjazhelaja voda) i izgotovlenija sovmestno prokatannyh jelementov. Vydeleny nekotorye harakternee momenty jetih razlichnyh metodov, chast' kotoryh horosho izvestna. Sistema EDF: izmerenie tolshhiny stenok trub iz urana ili iz uranovogo splava ul'trazvukom; vyjavlenie polostej v jetih trubkah s pomosh'ju gammagrafii; kontrol' za termicheskoj obrabotkoj ul'trazvukom jetih trub; izuchenie defektov (vkraplenija, treshhiny) ul'trazvukom v slitkah i zagotovkah obolochek iz MgZr; kontrol' za germetichnost'ju toplivnyh jelementov s pomoshh'ju gelija. Sistema EL 4: izmerenie tolshiny stenok silovyh trub i napravljajushhih trub iz cirkal- loja s pomoshh'ju ul'trazvuka i tokov Fuko; proverka s pomoshh'ju ul'trazvuka trub iz cirkal- loja, rasschitannyh na davlenie, i trubchatogo pokrytija iz nerzhavejushhej stali; vakuumnaja radiografija obolochek iz Be; kontrol' germetichnosti sterzhnej s pomoshh'ju gelija. Sovmestno prokatannye jelementy: izmerenie tolshhiny pokrytija pul'sirujushhimi tokami Fuko; vyjavlenie polozhenija serdechnika po otnosheniju k trubam i plastinkam s pomoshh'ju radiografii, scheta gamma-chastic i pul'sirujushhih tokov Fuko; kontrol' za gomogennost'ju topliva metodom scheta gamma-chastic; obnaruzhenie treshhin v slitkah iz ZrU s pomoshh'ju ul'trazvuka i gammagrafii; vyjavlenie otsloennyh uchastkov plastinok s pomoshh'ju ul'trazvuka, pul'sirujushhih tokov Fuko, a takzhe izmerenie udel

  6. Plasma Stability in Magnetic Mirror Machine with Stabilizing Rods; Stabilite du Plasma dans une Machine a Miroirs Magnetiques avec Barreaux de Stabilisation; Ustojchivost' plazmy v probkotrone so stabiliziruyushchimi sterzhnyami; Estabilidad del Plasma en una Trampa de Espejos con Barras Estabilizadoras

    Energy Technology Data Exchange (ETDEWEB)

    Trubnikov, B. A. [Institut Atomnoj Ehnergii Im. I.V. Kurchatova, Moskva, SSSR (Russian Federation)

    1966-04-15

    indica en la memoria, se puede conseguir la estabilizacion incluso en el caso limite de barras muy cortas, en el cual se las puede considerar como un sistema de 2n dipplos magneticos puntiformes, situados en, el plano central de la trampa de espejos, en una circunferencia de radio a y dirigidos en sentido radial desde el eje (o hacia el eje - las direcciones alternan). Estos sistemas, que hemos considerado a propuesta de Artsimovich, pueden ofrecer muy buenas perspectivas, ya que su estructura simplifica el acceso al plasma y permite instalar un equipo complementario para el diagnostico o el calentamiento del plasma. (author) [Russian] V nastojashhej rabote izvestnyj kriterij Greek-Small-Letter-Delta {integral} Script-Small-L / B < 0 obobshhaetsja na proizvol'nyj sluchaj aksial'no- nesimmetrichnyh polej. Dlja jetogo ego sleduet predstavit' v vide {integral}( Greek-Small-Letter-Delta B/B{sup 2}) (P{sub 0} + P{sub Up-Tack }) d Script-Small-L > 0. Zdes Greek-Small-Letter-Delta B = s x {Delta}B prirashhenie modulja polja na sosednej (vneshnej) silovoj linii, prichem s Up-Tack B. Ukazannyj kriterij primenjaetsja dlja issledovanija ustojchivosti plazmy v probkotrone so stabilizirujushhimi sterzhnjami. Pole vblizi osi opisyvaetsja skaljarnym potencialom: {psi} = {integral} B{sub 0} (z) dz - B{sub 0}{sup 1} (z) r 2/4 + g (z) r{sup n} cos n{phi} prichem dlja polja na samoj osi prinimaetsja parabolicheskaja approksimacija B{sub 0}(z) = B{sub 0}{sup 0} (1 + z{sup 2} /1{sup 2}). Esli 2p sterzhnej s tokom J v kazhdom raspolozheny na okruzhnosti'radiusa a, to ispol'zuja malost' velichiny r{sub 0}/1 << 1 mozhno privesti kriterij ustojchivosti k takomu vidu, chto v nem ostaetsja lish' parametr {alpha} = 4nJ Script-Small-L r{sub 0}{sup n-2}/ca{sup n} B{sup 0}{sub 0} i velichina x = z{sub max}/ Script-Small-L , where z{sub max} -maksimal'naja tochka otrazhenija chastic (z = 0 sootvetstvuet central'noj ploskosti probkotrona). Byli rassmotreny dva raspredelenija chastic: maksvellovskoe s

  7. Plasma Containment and Stability in a Megajoule Theta-Pinch Experiment; Confinement et Stabilite du Plasma dans un Dispositif a Striction Azimutale de un Megajoule; Uderzhanie i ustojchivost' plazmy pri provedenii ehksperimenta s' megadzhoulevym teta-pinchem; Confinamiento y Estabilidad del Plasma en un Experimento de Estriccion Azimutal de 1 MJ

    Energy Technology Data Exchange (ETDEWEB)

    Bodin, H. A.B.; Green, T. S.; Newton, A. A.; Niblett, G. B.F.; Reynolds, J. A. [United Kingdom Atomic Energy Authority, Culham Laboratory, Abingdon, Berks. (United Kingdom)

    1966-04-15

    sravnenija izmerennyh znachenij temperatur' jelektronov, diamagnetizma plazmy, radial'nogo raspredelenija plotnosti i vyhoda nejtronov so znachenijami, predskazannymi chislennymi gidromagnitnymi raschetami s ispol'zovaniem koda Gajna-Robertsa. V nastojashhee vremja s pomoshh'ju samyh raznoobraznyh metodov provoditsja izmerenie skorosti aksial'noj poteri plazmy v prisutstvii zahvachennyh parallel'nogo i obratnogo magnitnyh polej. Jeti metody vkljuchajut metody opticheskoj interferometrii dlja opredelenija obshhego chisla zahvachennyh chastic, analiz sploshnogo ispuskanija v vidimom spektre s cel'ju opredelenija plotnosti linij kak funkcii polozhenija v otnoshenii osi i ispol'zovanie miniatjurnyh p'ezojelektricheskih zondov dlja izmerenija razmera apertury pri poterjah. Rezul'taty pokazyvajut, chto plazma podverzhena diffuzii magnitnogo polja na rannih stadijah i ohlazhdeniju jelektronov libo radiaciej primesej, libo teplovoj provodimost'ju vdol' linij polja. Posledujushhee umen'shenie velichiny {beta} plazmy do znachenija okolo 0,5 pri pikovom pole uvelichivaet magnitnye apertury na koncah katushki i takim obrazom vedet k osevym poterjam plazmy. Sledovatel'no, glavnymi problemami na budushhee ostajutsja razrabotka sistemy predvaritel'nogo nagreva dlja pridanija plazme bolee vysokoj temperatury pri {beta} okolo edinicy i umen'shenie skorosti poteri jenergii jelektronov. (author)

  8. Present and Future Programmes in the Treatment and Ultimate Disposal of High-Level Radioactive Wastes in the United States of America; Programmes Actuels et Futurs de Traitement et d'Elimination Definitive des Dechets Radioactifs de Haute Activite aux Etats-Unis; 0422 0415 041a 0423 0429 0410 042f 0418 0411 0423 0414 ; Programas Estadounidenses Actuales y Futuros para el Tratamiento y Evacuacion Definitiva de Desechos de Elevada Radiactividad

    Energy Technology Data Exchange (ETDEWEB)

    Belter, W. G. [United States Atomic Energy Commission, Washington, DC (United States)

    1963-02-15

    sostojanie'', v tom chisle ispol'zovanie metoda dvizhushhegosja sloja, podogrevaemyh tigelej, forsunochnyh kolonn s teploizlucheniem, vrashhajushhihsja pechej i gubchatoj keramiki. Issleduetsja takzhe vozmozhnost' dobavlenija k othodam, stekloobra- zuzhhcih materialov dlja poluchenija bolee ustojchivogo konechnogo produkta. Otmechajutsja nekotorye preimushhestva i nedostatki kazhdogo iz jetih processov. Rezjumiruetsja sostojanie razrabotka jetih processov v nastojashhee vremja i privodjatsja nkmetki budushhej programmy. Privodjatsja rezul'taty obsledovanija specifichnyh geologicheskih obrazovanij, kak, naprimer, soljanyh zalezhej, glubokih vodoemov i vodonepronicaemyh kristallicheskih porod na predmet ispol'zovanija ih dlja okonchatel'nogo hranenija ili udalenija kal'cinirovannyh tverdyh veshhestv ili nekotoryh vidov zhidkih othodov. Obsuzhdajutsja plany predpolagaemyh polevyh jeksperimentov s real'noj aktivnost'ju v solenyh zalezhah. Kratko opisyvaetsja programma razvedochnogo burenija na zavode Savanna River dlja opredelenija vozmozhnostej hranenija staryh othodov pervogo cikla v korennyh porodah, zalegajushhih neposredstvenno v rajone zavoda. Soobshhajutsja predvaritel'nye rezul'taty. Dajutsja kratkie ukazanija otnositel'no dolgosrochnyh tehnologicheskih issledovanij, provodimyh v nastojashhee vremja v Okridzhe, dlja ocenki stepeni bezopasnosti i jekonomichnosti razlichnyh metodov obrabotki, hranenija i okonchatel'nogo udalenija zhidkih i tverdyh vysokoaktivnyh othodov. Obsuzhdaetsja rol' jetoj programmy tehnicheskoj ocenki v svjazi s dal'nejshim planirovaniem programmy obrabotki radioaktivnyh othodov. (author)

  9. Non-Destructive Methods for Determining Burn-Up in Nuclear Fuel; Methodes Non Destructives d'Evaluation du Taux de Combustion dans le Combustible Nucleaire; Metody opredeleniya vygoraniya v yadernom toplive bez razrusheniya obraztsa; Metodos No Destructivos para Determinai el Grado de Combustion de los Elementos Combustibles Nucleares

    Energy Technology Data Exchange (ETDEWEB)

    McGonnagle, W. J. [Illinois Institute of Technology, Chicago, IL (United States)

    1966-02-15

    jadernyh reaktorah bez razrushenija obrazca javljajutsja poleznymi i zhelatel'nymi. Ideal'nym byl by metod, ne trebujushhij special'nyh dannyh o nejtronnom spektre, istorii radiacii ili vremeni ohlazhdenija. Obluchennye toplivnye jelementy sami po sebe javljajutsja nositeljami informacii o stepeni vygoranija topliva. Jeta informacija soderzhitsja v forme radioaktivnyh i stabil'nyh izotopov, obrazujushhihsja v processe delenija. K sozhaleniju,kak pri metodah analiza topliva bez razrushenija obrazca, tak i s razrusheniem obrazca nejtronnyj spektr, istorija radiacii i period ohlazhdenija vlijajut na jetu informaciju. Tochno tak zhe nedostatok tochnyh jadernyh dannyh, takih, kak znachenija jadernyh poperechnyh sechenij, vlijaet na ljubye vychislenija, kotorye mozhno bylo by proizvesti. Drugoj trudnost'ju pri analizah bez razrushenija obrazca javljaetsja nalichie polej vysokoj radiacii, kotoraja vnosit dopolnitel'nyj ''shum'' v fon pri izmerenijah. Razrabotka poleznyh i real'nyh standartov javljaetsja trudnym delom. Metody analiza stepeni vygoranija bez razrushenija obrazca osobenno polezny togda, kogda trebuetsja bystro i jekonomichno, dazhe pri sushhestvujushhem polozhenii s ih nedostatkom, poluchit' zhelatel'nuju tochnost' priblizitel'noj velichiny vygoranija. Ispol'zovalos' neskol'ko metodov dlja opredelenija stepeni vygoranija bez razrushenija obrazca; vedetsja ih ocenka ili oni predlagajutsja. Ispol'zovalis' razlichnye tipy spektrometrov, v tom chisle spektrometry s izognutym kristallom, magnitnyj komptonovskij spektrometr, komptonovskij spektrometr na sovpadenija i scintilljacionnyj spektrometr dlja analiza gamma-izluchenija radioaktivnogo materiala, obrazujushhegosja vo vremja processa delenija. Drugie metody analiza bez razrushenija obrazca vkljuchajut aktivaciju fol'gi, propuskanie nejtronov, aktivacionnyj analiz, izmerenie zahvata gamma-luchej i izmerenie mgnovennyh i zapazdyvajushhih nejtronov. Rassmatrivajutsja osnovnye principy kazhdogo iz vyshenazvannyh metodov i

  10. Survey of Pulsed Neutron Source Methods for Multiplying Media; Methodes des Neutrons Pulses Pour l'Etude des Milieux Multiplicateurs; Obzor metodov s ispol'zovaniem istochnikov impul'snykh nejtronov dlya razmnozhayushchej sredy; Estudio Panoramico de los Metodos de Empleo de Fuentes de Neutrons Pulsados en Medios Multiplicadores

    Energy Technology Data Exchange (ETDEWEB)

    Garelis, E. [General Electric Company, Vallecitos Atomic Laboratory, Pleasanton, CA (United States)

    1965-10-15

    tratamiento del modo fundamental teniendo en cuenta la base teorica de las tecnicas de empleo de fuentes de neutrones pulsados que se han perfeccionado para el modelo (kO/E). Se exponen las repercusiones de la teoria de la fuente de neutrones pulsados en lo que se refiere a la obtencion de valores exactos de la constante de decrecimiento y de datos adecuados para el analisis de los sistemas pulsados. Tambien se examina la labor experimental realizada y se ponen de manifiesto tanto las ventajas como las limitaciones de la tecnica (k{beta}/ Script-Small-L ). El autor estudia tambien los metodos seudoaleatorios de respuesta a los impulsos, que utilizan una correlacion entre los datos de entrada y los de salida para determinar la funcion de Green de un conjunto multiplicador, y pone de manifiesto que la informacion obtenida con el metodo seudoaleatorio es identica a la conseguida por el metodo de la pulsacion reiterada. Por consiguiente, los metodos desarrollados para la tecnica de la pulsacion reiterada se pueden aplicar a la tecnica seudoaleatoria. (author) [Russian] V poslednie gody sushhestvovali dva napravlenija v oblasti jeffektivnyh sposobov poluchenija izmerenii ostatochnoj reaktivnosti s ispol'zovaniem ge- neratorov impul'snyhnejtronov: 1) obychnye izmerenija s istochnikom impul'snyh nejtronov pri nepreryvnom pul'sirujushhem istochnike i 2) metody, osnovannye na psevdosluchajnom otvete impul'sa s ispol'zovaniem sootnoshenija mezhdu vhodom i vyhodom. V oboih sluchajah po- luchaemaja informacija identichna, t.e. oba napravlenija ideal'no sluzhat opredeleniju otvetnoj funkcii. Razrabotka metodov s istochnikom impul'snyh nejtronov na teplovyh sistemah v celjah izmerenija reaktivnosti proslezhivaetsja ot pervonachal'nyh popytok Sjoestrand do nedavnego metoda (k{beta}/ Script-Small-L ). Pri obychnom metode s istochnikom impul'snyh nejtronov funkcija podkriti- cheskoj sborki Grina, otvet reaktora na del'ta-funkciju istochnika nejtronov, predstavljaet soboj poisk svojstv

  11. Radiation Polymerization in the Solid Phase; Polymerisation radiochimique en phase solide; Radiatsionnaya polimerizatsiya v tverdoj faze; Radiopolimerizacion en fase solida

    Energy Technology Data Exchange (ETDEWEB)

    Barkalov, I. M.; Gol' danskij, V. I.; Enikolopov, N. S.; Terekhova, S. F.; Trofimova, G. M.

    1963-11-15

    energfa de activacion, a diferencia de la postpolimerizacion lenta, que exige la misma energia de activacion que el proceso en fase liquida. (author) [Russian] Radiatsionnoj polimerizatsii tverdykh i zamorozhennykh monomerov za poslednee vremya udelyaetsya bol'shoe vnimanie. EHtot vopros predstavlyaet bol'shoj interes kak s prakticheskoj tochki zreniya, tak i s tochki zreniya novykh teorij khimicheskoj kinetikich radiatsionnoj khimii. Kak izvestno, strogaya prostranstvennaya uporyadochennost' monomernykh edinits v polimere obuslavlivaet rezkoe uluchshenie fiziko-mekhanicheskikh svojstv bez izmeneniya khimicheskogo sostava. Dlya sinteza stereoregulyarnykh polimerov ispol'zuetsya printsip matritsy, t.e. monomernaya edinitsa strogo orientiruetsya v prostranstve putem obrazovaniya kompleksa s katalizatorom ili kakim-libo drugim veshchestvom. Naprimer, pri radiatsionnoj polimerizatsii ryada monomerov, orientirovannykh v klatratnykh kompleksakh mocheviny i tiomocheviny, polucheny kristallicheskie stereopegulyarnye polimery. Odnako naibolee prostym variantom yavlyaetsya orientatsiya monomera v sobstvennoj kristallicheskoj reshetke. Khotya mnogie teoreticheskie voprosy v ehtoj oblasti ostayutsya neyasnymi, prakticheskoe ispol'zovanie ehtogo sposoba ves'ma zamanchivo. Tak, pri radiatsionnoj polimerizatsii kristallicheskogo trioksana uzhe poluchen vysokokristallicheskij polioksimetilen. Trebuetsya, odnako, dal'nejshaya teoreticheskaya razrabotka ehtogo metoda. Neobkhodimo dlya kazhdogo otdel'nogo monomera vyyasnit' vklad razlichnykh vidov reaktsij, proiskhodyashchikh pri obluchenii i posleduptsem plavlenii tverdykh monomerov (spetsificheskaya radiatsionnaya reaktsiya, postpolimerizatsiya i polimerizatsiya v tochkakh fazovykh perekhodov) v obshchuyu kartinu protsessa. Vypolnennoe v poslednee vremya v Institute khimicheskoj fiziki podrobnoe issledovanie kinetiki radiatsionnoj tverdofaznoj polimerizatsii ryada monomerov s primeneniem kalorimetricheskogo metoda i s nablyudeniem signala

  12. The Hanford Emergency Dosimetry System; Le Systeme de Dosimetrie pour les Cas d'Urgence a Hanford; 0421 0418 0421 0422 0414 ; El Sistema Dosimetrico de Hanford para Casos de Urgencia

    Energy Technology Data Exchange (ETDEWEB)

    Larson, H. V.; Keene, A. R. [Radiation Protection Operation, Hanford Laboratories, General Electric Company, Hanford Atomic Products Operation, Richland, WA (United States)

    1965-06-15

    dosimetros contienen laminas de los mismos elementos que el dosimetro de pelicula y constituyen un medio mas para calcular la dosis individual. (author) [Russian] Proekt v Hjenforde predstavljaet soboj bol'shoj atomnyj promyshlennyj kompleks, v kotoryj vhodjat jadernye reaktory, zavody po proizvodstvu teplovydeljajushhih jelementov, ustanovki dlja himicheskogo razdelenija i issledovatel'skie laboratorii. V dopolnenie k programme nabljudenija i kontrolirovanija radiacionnogo obluchenija personala razrabotana sistema avarijnogo dozimetricheskogo kontrolja s cel'ju obespechenija bystroj ocenki bol'shih doz, provedenija otbora sluzhashhih i kontrolja nad nimi, preduprezhdenija personala i sozdanija centrov avarijnogo kontrolja personala, ocenki vneshnih doz obluchenija, ocenki soderzhanija radioaktivnyh materialov v organizme, obnaruzhenija i regulirovanija zagrjaznenija okruzhajushhej sredy i bystrogo sostavlenija dannyh ob obluchenii v kachestve rukovodstva dlja personala skoroj pomoshhi i vrachej. Osnovnoj upor delaetsja na hjenfordskij plenochnyj dozimetr, kotoryj imeet pri sebe vse lica v predelah kontroliruemyh zon. Dozimetr obespechivaet pravil'noe vyjavlenie lichnosti vladel'ca, a ocenka plenki mozhet byt' provedena v techenie 90 minut. Razdel'no, i vmeste s tem odnovremenno, mozhno provesti obrabotku ostal'nyh sostavnyh chastej dozimetra s cel'ju opredelenija spektra nejtronov i velichiny dozy v pjati gruppah jenergii, a takzhe dat' bystruju ocenku nejtronnoj dozy pri odnokratnom stolknovenii, ot neskol'kih do tysjach rad. Gamma-luchi obnaruzhivajutsja v diapazone ot 20 millirentgen do 1500 rentgen (pri obrabotke komponentov plenki) i ot 10 do 10 000 rentgen (pri obrabotke jekranirovannyh tantalom ftoristyh sterzhnej). V avarijnuju sistemu vkljuchajutsja programmy, obespechivajushhie ponimanie sotrudnikami sistemy, podgotovku v oblasti dozimetrii i sotrudnichestvo s rukovodstvom v dele bystrogo vyjavlenija, kontrolirovanija i izolirovanija porazhennyh izlucheniem

  13. Performance Characteristics of the Experimental Boiling Water Reactor from 0 to 100 MW(t); Performances de l'EBWR de 0 a 100 MW; Rabochaya kharakteristika ehksperimental'nogo kipyashchego reaktora EBWR pri moshchnosti 0 - 100 mgvt.; Rendimiento del reactor experimental de agua hirviente (EBWR) entre 0 y 100 MW

    Energy Technology Data Exchange (ETDEWEB)

    Iskenderian, A.; Lipinski, W. C.; Petrick, M.; Wimunc, E. A. [Argonne National Laboratory, Argonne, IL (United States)

    1963-10-15

    entonces de comportarse como reactor de agua hirviente de ciclo directo; en cierto modo, funciona como reactor de ciclo doble y circulacion natural. (author) [Russian] 25 maya 1962 goda Argonnskaya natsional'naya laboratoriya poluchila razreshenie KAEH SSHA na ehkspluatatsiyu reaktora EBWR na moshchnosti 100 mgvt. Administrativnoe razreshenie na ehkspluatatsiyu reaktora bylo predostavleno sistemoj garantij. Mezhdunarodnogo agentstva po atomnoj ehnergii 11 iyulya 1961 goda. 15 noyabrya 1962 goda byl dostignut uroven' moshchnosti v 100 mgvt. 6 dekabrya 1962 goda ehksperimental'naya programma byla zakonchena. Odnoj iz osnovnykh tselej ee byla tshchatel'naya proverka reaktora dlya polucheniya dannykh i informatsii rabochej kharakteristiki ehtogo tipa reaktora. Ehta programma byla pervoj programmoj takogo roda i pervoj vypolnennoj programmoj. Dlya polucheniya nuzhnykh dannykh neobkhodimo bylo razrabotat' mnogie novye pribory. TSel' byla dostignuta, polucheno mnogo novykh dannykh o rabochej kharakteristike kipyashchego reaktora s estestvennoj tsirkulyatsiej. Tak,naprimer, poluchena informatsiya otnositel'no skorosti potoka tsirkulyatsii v zamknutom tsikle, predelov separatsii zhidkogo para (vydelenie para v osadok v spusknoj trube i unos zhidkosti ehflu- entom para), nedogreva, lokalizatsii dejstvitel'noj poverkhnosti razdela v reaktore i ee svyazi s urovnem vodnoj kolonki, skorosti razrusheniya para v spusknoj trube, pustotnykh koehffitsientov, reaktivnoj sposobnosti H{sub 3}BO{sub 3}, temperaturnykh koehffitsientov, ispol'zovaniya sterzhnej iz bora dlya tselej kontrolya, ispol'zovaniya svezhikh toplivnykh ehlementov, peredatochnykh funktsij,analiza shuma, nekotorykh izmerenij potoka, stabil'nosti i t.d. Krome togo, byli polucheny dannye o povedenii i tselostnosti nekotorykh reaktornykh komponentov i sistem, takikh, kak bornokislaya kontrol'naya reaktsiya, urovni radiatsii, raspredelenie produktov korrozii, vykhod iz stroya oborudovaniya, toplivo i reguliruyushchie sterzhni i t

  14. Quality Selection of Zircaloy-2 Canning Tubes by Ultrasonic Testing on Small Defects; Controle de la Qualite des Gaines en Zircaloy-2: Detection de Petits Defauts par les Ultrasons; Achestvennyjotb ortrub chatykh obolochek iz tsirkalloya-2 putem vyyavleniya nebol'shikh defektov s pomoshch'yu ul'trazvuka; Control de Calidad de los Revestimientos de Zircaloy-2 por Localizacion Ultrasonica de Pequenos Defectos

    Energy Technology Data Exchange (ETDEWEB)

    Van Der Linde, A. [Reactor Centrum Nederland, Petten (Netherlands); Deraad, J. A. [Roentgen Technische Dienst N.V., Rotterdam (Netherlands)

    1965-09-15

    , de los 93 tubos ensayados, 21 presentaban defectos transversales de 10 a 50 {mu}m de profundidad. Por consiguiente, puede afirmarse que el procedimiento indicado permite clasificar los tubos con arreglo a su calidad. (author) [Russian] Trubchatye obolochki iz cirkalloja-2 s vnutrennim diametrom 10,20 mm, tolshhinoj stenok 0,90 mm i dlinoj 1500 mm, prednaznachennye dlja proverki v kachestve pokrytija toplivnyh sterzhnej pri temperature 330 Degree-Sign S v reaktornoj petle s vodoj pod davleniem ispytyvalis' s pomoshh'ju ul'trazvuka s cel'ju obnaruzhenija defektov. Ispytyvaemye trubchatye obolochki byli postavleny izgotoviteljami v SShA, soedinennom Korolevstve i v Skandinavii. Nashe trebovanie, chtoby vse postavlennye trubki byli svobodny ot treshhin i drugih defektov razmerom svyshe 500 - 1000 mikron po dline i svyshe 25 - 50 mikron po glubine, ne bylo prinjato polnost'ju izgotoviteljami. Oni mogli garantirovat' tol'ko otsutstvie treshhin velichinoj svyshe 1000 mikron po dline i svyshe 50 mikron po glubine. V svjazi s tem, chto iz 93 ispytannyh trub tol'ko u dvuh byli obnaruzheny treshhiny velichinoj svyshe 50 mikron po glubine, reshili provodit' bolee stroguju proverku, v rezul'tate kotoroj mozhno bylo by obnaruzhivat' defekty velichinoj porjadka 10 - 50 mikron po glubine. Dlja obnaruzhenija i registracii takih nebol'shih defektov primenjalos' poluavtomaticheskoe ul'trazvukovoe impul'snoe oborudovanie, dejstvujushhee kak v prodol'nom, tak i v poperechnom napravlenijah, v kombinacii s sistemami propuskanija i mnogokanal'nym registratorom. Sistema razvertki byla otregulirovana takim obrazom, chto vnutrennie i naruzhnye defekty odnogo i togo zhe porjadka i razmera ukazyvalis' s odinakovymi amplitudami. Kalibrovanie oborudovanija proizvodili na iskusstvennyh defektah. Defekty, obrazovavshiesja v prodol'nom napravlenii, obnaruzhivalis' s pomoshh'ju razdel'noj sistemy datchik-priemnik s primeneniem fokusirovannogo puchka. Defekty, obrazovavshiesja v poperechnom napravlenii

  15. Power Reactor Design at Zero Power; Etudes de Reacteurs de Puissance, au Moyen de Machines de Puissance Zero; Konstruktsiya ehnergeticheskogo reaktora nulevoj moshchnosti; Diseno de Reactores Generadores con Ayuda de Reactores de Potencia Nula

    Energy Technology Data Exchange (ETDEWEB)

    Redman, W. C.; Plumlee, K. E.; Baird, Q. L. [Argonne National Laboratory, Argonne, IL (United States)

    1964-02-15

    obsuzhdenii programm ob{sup j}asnjajutsja obstojatel'stva, vlijajushhie na vybor jeksponen- cial'nyh i chisto kriticheskih sborok, maketov ustanovok nulevoj moshhnosti i jeksperimen- tov na samom reaktore dlja poluchenija neobhodimyh dannyh, a takzhe ta rol', kotoruju igrajut vspomogatel'nye analiticheskie raboty. Na konkretnyh primerah pokazyvaetsja, kakie mo- gut byt' polucheny dannye do nachala raboty reaktora na moshhnosti. Jeti dannye vkljuchajut ostatochnuju reaktivnost' vykljuchennogo reaktora, zapas reaktivnosti dlja jekspluatacionnyh nuzhd, temperaturnye kojefficienty, jeffektivnost' regulirujushhih i avarijnyh sterzhnej, kinetiku reaktora, harakteristiki proizvodstva jenergii, trebovanija v otnoshenii puskovogo istochnika i chuvstvitel'nosti priborov, trebovanija v otnoshenii zashhity i balans nejtro- nov . V obzore nedavnih jeksperimentov v reaktorah nulevoj moshhnosti vyjavljaetsja bol'shaja rol', kotoruju igrajut v poslednee vremja jeksponencial'nye i kriticheskie sistemy v vypol- nenii Argonskoj laboratoriej zadach po razrabotke konstrukcij reaktorov. Ih rol' v budu- shhem vidna iz kratkogo izlozhenija osushhestvljaemyh i zaplanirovannyh programm dlja sem'i dejstvujushhih reaktorov nulevoj moshhnosti Argonskoj laboratorii i ozhidaemogo popolnenija. (author)

  16. Shippingport Atomic Power Station Operating Experience, Developments and Future Plans; La centrale nucleaire de Shippingport, experience de son fonctionnement et plans pour l'avenir; Shippingportskaya atomnaya ehlektrostantsij, opyt ehkspluatatsii, usovershenstvovaniya i plany na budushchee; Central nucleoelectrica de Shippingport; experiencia adquirida con su explotacton y programa de desarrollo

    Energy Technology Data Exchange (ETDEWEB)

    Feinroth, H. [Division of Reactor Development, United States Atomic Energy Commission, Washington, DC (United States); Oldham, G. M. [Shippingport Atomic Power Station, Duquesne Light Company, Pittsburgh, PA (United States); Stiefel, J. T. [Bettis Atomic Power.Labora Tory, Westinghouse Electric Corporation, Pittsburgh, PA (United States)

    1963-10-15

    'mennykh administrativnykh instruktsij, rukovodstv po ehnergeticheskoj ustanovke i t.d., chto yavilos' ochen' vazhnym faktorom v uspeshnom osushchestvlenii programmy ispytanij SHippingportskoj ehlektrostantsii. Rezul'taty ispytanij khorosho sovpadayut s raschetnymi dannymi. Rassmatrivayutsya rabota aktivnoj zony reaktora, stabil'nost' ustanovki, chuvstvitel'nost' k izmeneniyam nagruzki, rabota toplivnykh ehlementov i reguliruyushchikh sterzhnej, povyshenie takikh dlitel'nykh ehffektov, kak korroziya i intensivnost' izlucheniya, rabota komponentov i t.d. Rassmatrivaetsya osnovnaya tsel' tekushchej i budushchej programm Shippingportskogo proekta v otnoshenii usovershenstvovaniya osnovnoj tekhnologii reaktorov s vodyanym okhlazhdeniem. Ehta programma vklyuchaet prodolzhenie ehkspluatatsii Shippingportskoj ustanovki, razrabotku, konstruirovanie, izgotovlenie i opytnuyu ehkspluatatsiyu vtoroj aktivnoj zony (aktivnaya zona 2), imeyushchej dlitel'nyj srok sluzhby i vysokuyu plotnost' ehnergovydeleniya. Imeya proektnuyu ehlektricheskuyu moshchnost' brutto 150 mgvt i prodolzhitel'nost' sluzhby pervoj zapal'noj sborki 10 tys. chasov raboty na polnoj moshchnosti, aktivnaya zona 2 budet v pyat' s polovinoj raz moshchnee aktivnoj zony 1 i obladat' v dva raza bol'shej plotnost'yu ehnergovydeleniya, chem poslednyaya. Daetsya opisanie konstruktsii aktivnoj zony 2 i svyazannykh s nej osnovnykh usovershenstvovanij v fizike reaktora, metallurgii, teploperedache, podache teplonositelya i izgotovlenii toplivnykh ehlementov. Izlozheny plany v otnoshenii dezaktivatsii reaktornoj ustanovki i osushchestvleniya ee modifikatsii v svyazi s ustanovkoj bolee moshchnoj aktivnoj zony 2. (author)

  17. Void Reactivity Effects in the Second Charge of the Halden Boiling Water Reactor; Effets Cavitaires dans la Deuxieme Charge du Reacteur a Eau Lourde Bouillante de Halden (HBWR); Ehffekty pustotnoj reaktivnosti vo vtoroj zag HBWR; Effectos de Cavitacion en la Segunda Carga del Reactor de Agua Pesada Hirviente de Halden (HBWR)

    Energy Technology Data Exchange (ETDEWEB)

    Lunde, J. E. [OECD Halden Reactor Project (Norway)

    1964-02-15

    temperaturas elevadas. La concordancia es menos satisfactoria para valores intermedios del volumen relativo de los vacios. El efecto de reactividad se calcula macroscopicamente mediante una teoria de las perturbaciones. (author) [Russian] Jeffekt reaktivnosti pustot, vyzvannyh kipeniem v kanalah dlja teplonositelja vo vtoroj zagruzke Haldejskogo kipjashhego tjazhelovodnogo reaktora (HBWR) byl izmeren kak v jeksperimentah nulevoj moshhnosti s imitaciej pustot, tak i v uslovijah fakticheskoj moshhnosti. Jeksperimenty s imitirovannymi pustotami sostojali v izmerenii jeffekta reaktivnosti pustotnyh kolonn, vvodimyh v tonkostennye trubki na razlichnuju glubinu. Trubki byli ustanovleny v raznyh polozhenijah mezhdu prodol'nymi rebrami v odinochnoj sborke, sostojashhej iz semi sterzhnej, prakticheski identichnoj normal'nym toplivnym jelementam vtoroj zagruzki. Jetot jeksperiment pozvolil izuchit' zavisimost' reaktivnosti ot pustogo ob{sup e}ma, a takzhe zavisimost' reaktivnosti ot polozhenija puzyr'kov para v kanale dlja teplonositelja. Jeksperiment byl vypolnen na norvezhskoj ustanovke nulevoj moshhnosti NORA s aktivnoj zonoj iz 36 jelementov vtoroj zagruzki i s geometriej reshetki, analogichnoj geometrii reshetki reaktora HBWR. Temperaturnaja zavisimost' pustotnogo jeffekta byla izuchena na jeksperimental'noj ustanovke nulevoj moshhnosti, imevshej aktivnuju zonu Iz 100 toplivnyh jelementov reaktora HBWR. V odinochnom toplivnom jelemente uroven' vody v kanale dlja teplonositelja snizhalsja do razlichnyh glubin i vlijanie na reaktivnost' jetogo otklonenija ot normal'nyh uslovij izmerjalos' pri razlichnyh temperaturah a intervale temperatur 50 -220eS. Vlijanie pustotnoj reaktivnosti na moshhnost' bylo izmereno na reaktore HBWR kak funkcija jadernoj jenergii pri razlichnyh temperaturah zamedlitelja v diapazone 150 -230e S pri moshhnostjah do 16mgvt (pri samoj vysokoj temperature). Kojefficient pustotnoj reaktivnosti na moshhnosti javljaetsja vazhnym pokazatelem pri opredelenij

  18. Plant Measurement, Sampling and Analysis for Accountancy Purposes with Particular Reference to Separation Plants at Windscale; Mesures, Echantillonnages et Analyses en Usine a des Fins Comptables, Notamment dans les Installations de Separation de Windscale; Izmereniya, vzyatie obraztsov i analizy v tselyakh ucheta na opyte ustanovki razdeleniya radioizotopov v uindskejle; Medicion, Muestreo y Analisis para Fines Contables, Especialmente en las Plantas de Separacion de Windscale

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, A. S.; Elliott, F.; Powell, R.; Swinburn, K. A. [United Kingdom Atomic Energy Authority, Windscale and Calder Works, Cumberland (United Kingdom)

    1966-02-15

    ). La precision requerida del metodo de analisis quimico depende del numero de determinaciones que se efectuen en cada periodo contable. Asi, para un metodo minucioso pero impreciso es necesario proceder a un gran numero de analisis. Puede resultar mas economico efectuar menos determinaciones con un metodo mas preciso. En la memoria se exponen detalladamente los metodos para la determinacion del plutonio: a) radioquimicos, b) colorimetricos, con toronol, c) separacion del plutonio, formacion del complejo con exceso de EDTA y retrovaloracion del reactivo, d) volumetria, e) dilucion isotopica seguida de espectrometria de masas, y f) espectrometria diferencial. Tambien se resenan los metodos de determinacion del uranio: a) gravimetria en forma de U{sub 3}O{sub 8}, b) extraccion con eter seguida de gravimetria o calorimetria, c) volumetria, d) dilucion isotopica seguida de espectrometria de masas y e) determinacion del enriquecimiento por espectrometria de masas o por espectrografia del desplazamiento de las lineas de un espectro de emision. En todos los procedimientos contables se emplean patrones para controlar los analisis y descubrir las inexactidudes que deben corregirse. En la memoria se dan precisiones sobre todos los metodos y se indica cuales de ellos se emplean en la nueva planta de separacion. (author) [Russian] Vse cifry dlja podscheta kolichestva special'nyh materialov vkljuchajut odin ili bolee iz treh osnovnyh parametrov, a imenno: izmerenija na ustanovke, vzjatie obrazcov i vzjatie analizov. Chto kasaetsja izmerenij, provodimyh na ustanovke, to luchshe vsego ispol'zovat' vzveshivanie tam, gde jeto vozmozhno, naprimer, kolichestvo plutonija pri zagruzke v novuju ustanovku razdelenija izotopov opredeljaetsja na osnove vesa zagruzhennyh uranovyh sterzhnej. Podrobno obsuzhdajutsja metody izmerenija velichin, naprimer a) pnevmaticheskogo merkatora i b) indikatornogo metoda s ispol'zovaniem radioaktivnogo cezija. Privodjatsja proverennye vykladki kazhdogo metoda

  19. Study of Fluidized-Bed Control Rods; Etude de Barres de Controle Fluidisees; Izuchenie reguliruyushchej sistemy, ispol'zuyushchej suspenziyu pogloshchayushchikh chastits; Estudio Sobre Barras de Control de Lecho Fluidificado

    Energy Technology Data Exchange (ETDEWEB)

    Blair, D. J. [General Nuclear Engineering Corporation, Dunedin, FL (United States); Driscoll, M. J.; Dalton, G. R.; Parkinson, T. F. [Department of Nuclear Engineering, University of Florida, Gainesville, FL (United States)

    1964-06-15

    sistemu trub podobno sistemam upravlenija, razrabatyvaemym dlja reaktorov s suspenziej topliva. Nekotorye iz vozmozhnyh preimushhestv koncepcii SPCh: 1) ustranjaetsja bol'shinstvo vvodov v verhnjuju chast' korpusa i uproshhaetsja process peregruzki topliva; 2) pri vozniknovenij avarii v rezul'tate poteri potoka proishodit avtomaticheskaja bystraja ostanovka reaktora; 3) osevoe raspredelenie moshhnosti mozhet izmenjat'sja v rezul'tate primenenija special'nyh kanalov ili chastic peremennoj velichiny; 4) rezkoe vozrastanie potoka v vodjanom zazore mozhet byt' umen'sheno dlja chastichno izvlechennogo upravljajushhego sterzhnja; 5) mozhno umen'shit' temperaturnyj ''zapas'' reaktivnosti,esli sistema imeet otricatel'nyj temperaturnyj kojefficient; 6) rashody po izgotovleniju znachitel'no nizhe, chem dlja jelektromehanicheskih sistem. Provedena ocenka koncepcii SMCh, v tom chisle bylo osushhestvleno stroitel'stvo pro- totipnyh modelej i proverka gidravlicheskih i jadernyh harakteristik. Izuchalis' dva tipa: propuskajushhie ''sterzhni'' (tolshhina 2 srednih svbbodnyh probega) i otrazhajushhie ''sterzhni'' (tolshhina 4 srednih svobodnyh probega). Dlja oboih tipov mozhno poluchit' priemlimye gidravlicheskie i jadernye harakteristiki. Obosnovana vozmozhnost' upravlenija reaktorami nizkoj moshhnosti s pomoshh'ju propuskajushhih ili otrazhajushhih upravljajushhih ' sterzhnej''. Dalee bylo pokazano, chto SPCh obladajut horoshimi regulirujushhimi svojstvami, kotorye mozhno rasschitat' standartnymi metodami. V sluchae bol'shoj moshhnosti i vysokoj temperatury neobhodima dopolnitel'naja informacija otnositel'no harakteristik materiala chastic. Bol'shoe preimushhestvo SPCh zakljuchaetsja v vozmozhnosti formirovanija osevogo potoka libo putem ispol'zovanija chastic razlichnoj velichiny i pogloshhenija, libo zhe putem.sootvetstvujushhego formirovanija oblasti poperechnogo sechenija SPCh. (author)

  20. Measurements of the Asymptotic Spectrum of a Multiplying Medium; Mesures du Spectre Asymptotique d'Un Milieu Multiplicateur; Izmereniya asimptoticheskogo spektra umnozhayushchej sredy; Mediciones del Espectro Asintotico en un Medio Multiplicador

    Energy Technology Data Exchange (ETDEWEB)

    Slovacek, R. E.; Cerbone, R. J.; Gaerttner, E. R.; Fullwood, R. R.; Bach, D. R. [Rensselaer Polytechnic Institute, Troy, NY (United States)

    1965-08-15

    'presenta una distribucion espacial persistente que se presta mas al analisis, los autores estiman que la tecnica de medicion del espectro asintotico aplicada a sistemas multiplicadores ha de resultar en extremo util en el estudio del problema del espectro espacial en un amplio intervalo energetico. (author) [Russian] Asimptoticheskij (po vremeni) spektr umnozhajushhej sredy predstavljaet interes ne tol'ko dlja provedenija jeksperimentov po analizu pul'sirujushhih nejtronov, no i takzhe dlja izuchenija svojstv nejtronnoj diffuzii sredy. Dlja izmerenija asimptoticheskogo nejtronnogo spektra v razmnozhajushhej sisteme razrabotan istochnik pul'sirujushhih nejtronov-mehanicheskij preryvatel'. Osushhestvleno izmerenie poverhnosti i centra (skaljara) spektra kazhdoj iz chetyreh razmnozhajushhih sistem, daetsja sravnenie s raschetami spektra. Vo vseh razmnozhajushhih sistemah v kachestve zamedlitelja ispol'zovalsja obogashhennyj uran-235 i vodorod. Dve sistemy byli izgotovleny iz toplivnyh sterzhnej, pokrytyh cirkoniem v vode; dve drugih sistemy byli izgotovleny iz smesi poroshkov UO{sub 2} i ZrO{sub 2}, dispergirovannyh v parafine. Razmery i proporcii vodoroda po otnosheniju k uranu-235 brali razlichnye s tem, chtoby raznoobrazit' absorbciju, utechku i rassejanie. Skaljarnyj spektr vyschityvali na osnovanii teorii staticheskoj diffuzii. Sovpadenija mezhdu izmerennym i skaljarnym spektrom okazyvalis' udovletvoritel'nymi, kogda dlja vychislenija spektra ispol'zovalas' izmerennaja velichina asimptoticheskoj postojannoj raspada. Najdeno, chto vyschitannyj asimptoticheskij spektr javljaetsja chrezvychajno chuvstvitel'nym k postojannoj raspada; 7%-noe izmenenie v postojannoj raspada dlja odnoj iz sistem dalo v rezul'tate 47%-noe izmenenie v teplovom sostojanii k zamedleniju otnoshenija potokov. Poverhnostnyj spektr dlja dvuh iz sistem poluchen pri ispol'zovanii dvojnogo vychislenija R1. Vychislenie poverhnostnogo spektra sovpalo s dannymi v teplovoj oblasti do 0,2 ev. Odnako pri

  1. Radioisotopes and Radiation in Animal and Plant Insect Pest Control; Emploi des radioisotopes et des rayonnements dans la lutte contre les insectes nuisibles aux plantes et aux animaux; Ispol'zovanie radioizotopov i radiashchi v bor'be s nasekomymi-vreditelyami rastenij i zhivotnykh; Utilizacion de los radioisotopos y de las radiaciones en la lucha contra los insectos nocivos para las plantas y los animales

    Energy Technology Data Exchange (ETDEWEB)

    Andreev, S. V.; Martens, B. K.; Samojlova, V. A.; Molchanova, Z. I. [Vsesoyuznyj Institut Zashchity Rastenij, Leningrad, SSSR (Russian Federation)

    1963-09-15

    plagas de insectos. La accion esterilizadora y letal de las radiaciones ionizantes puede ser muy eficaz en la lucha contra las plagas de insectos. Utilizando rayos gamma se han establecido las dosis esterilizadoras para toda una serie de insectos nocivos para los productos agricolas almacenados (Calandra granaria L., Acanthoscelides Obtectus Say, Pectinophora Malvella Hb., Leptinotarsa decemlineota Say, Chloridea obsoleta F.) y los cultivos. Los datos obtenidos con esas investigaciones serviran de base para elaborar y perfeccionar los metodos de lucha contra los insectos daninos para la agricultura. (author) [Russian] Problema bor'by s vreditelyami sel'skokhozyajstvennykh kul'tur imeet krupnoe narodnokhozyajstvennoe znachenie. Pri razreshenii ehtoj problemy osoboe znachenie priobretaet ispol'zovanie poslednikh dostizhenij nauki. V tselyakh ratsionalizatsii i povysheniya ehffektivnosti sushchestvuyushchikh metodov bor'by s vrednymi nasekomymi byli ispol'zovany radioaktivnye izotopy i izlucheniya. Ispol'zovanie radioaktivnykh izotopov i izluchenij yavlyaetsya moguchim sredstvom ratsionalizatsii i'povysheniya ehffektivnosti sushchestvuyushchikh metodov bor'by s vrednymi nasekomymi. Razrabotka ehtikh metodov vyzyvaet neobkhodimost' detal'nogo izucheniya voprosov bioehkologii, toksikologii i t.d. V oblasti bioehkologii ves'ma perspektivnym yavlyaetsya metod radiomarkirovki nasekomykh. Primenenie radioizotopov dlya markirovki nasekomykh vreditelej zernovykh kul'tur (Eurygaster integriceps Put, Hadena sordida Skh.) i ikh parazitov (Meniscus agriatus Crow, Psendogonia cinerascens Rond.) pozvolilo ustanovit' razmery migratsij ikh, opredelit' mesta rezervatsij, chislennost' populyatsij i izuchit' voprosy pitaniya ukazannykh parazitov vrednykh nasekomykh. Ehtim khe metodom byla ustanovlena dinamika rasprostraneniya karantinnogo ob{sup e}kta kartofel'nogo khuka (Leptinotarsa decemlineota Say), chto pozvolilo poluchit' neobkhodimye dannye dlya provedeniya istrebitel'nykh meropriyatij

  2. Determination of the Uranium Content of Aluminium Alloys; Determination de la Teneur en Uranium dans les Alliages a Base d'Aluminium; Opredelenie soderzhaniya urana v splavakh na osnove alyuminiya; Determinacion del Contenido de Uranio en las Aleaciones a Base de Aluminio

    Energy Technology Data Exchange (ETDEWEB)

    Gerard, J.; Van Hove, L. [S.A. Metallurgie et Mecanique Nucleaires Dessel (Belgium)

    1965-09-15

    trebuet sobljudenija mer predostorozhnosti, a ih razrabotka javljaetsja medlennym i dorogostojashhim processom. No dlja dannoj produkcii, kak tol'ko budet sdelan vybor, edinstvennym prakticheskim zatrudneniem okazhetsja nabljudenie za jelektronnoj ustojchivost'ju ustanovki. Drugie vysheukazannye metody, a imenno himicheskie i izotopnye analizy i densito- metricheskie izmerenija, obychno ne primenjajutsja. Izmerenie potemnenija radiograficheskogo snimka ne javljaetsja nedostatochno tochnym i ne pozvoljaet opredeljat' soderzhanie urana s zhelaemoj tochnost'ju. Tem ne menee, densitometricheskie issledovanija radiograficheskih snimkov javljajutsja ochen' poleznymi, a chasto i neobhodimymi dlja ocenki gomogennosti splava ili ego srednego soderzhanija, sravnimogo s dvumja krajnimi jetalonami, imejushhimisja na tom zhe snimke. Himicheskie i izotopnye analizy mogut byt' ochen' tochnymi, no oni javljajutsja razrushitel'nymi. Opredelennye jekspluatacionnye predostorozhnosti dolzhny byt' prinjaty, chtoby, s odnoj storony, ustranit' oshibki, obuslovlennye nalichiem himicheskih primesej v splave, a s drugoj-uchest' nalichie razlichnyh izotopov urana, v otnoshenii kotoryh neobhodimo znat' sootnoshenie dlja tochnogo rascheta soderzhanija urana-235. V zakljuchenie govoritsja, chto izmerenie soderzhanija urana neobhodimo provodit' v neskol'ko jetapov s ispol'zovaniem vseh otnositel'no prostyh metodov. Ukazyvaetsja na znachenie i predely kazhdogo jetapa. Vybor jetalonov osnovan na izuchenii radiograficheskih snimkov. Izmerenie tochnogo soderzhanija urana-235 provoditsja na osnove himicheskih i izotopnyh analizov. Kontrol' v promyshlennom masshtabe osushhestvljaetsja putem izmerenija plotnosti splava ili po urovnju gamma-izluchenija urana-235. Tochnost' oboih metodov sravnima (otnositel'no {+-}0,5%). S jekonomicheskoj tochki zrenija rekomenduetsja provodit' opredelenie soderzhanija putem scheta gamma-chastic v sluchae neobhodimosti provedenija bol'shoj serii issledovanij na predmetah

  3. The Cobalt-60 Research Facility at Seibersdorf; L'Installation de Recherche sur l'Iradiation au {sup 60}Co de Seibersdorf; Obluchayushchaya ustanovka s istochnikom Kobal'ta-60 reaktornogo tsentra v Zajbersdorfe; La Instalacion Experimental de {sup 60}Co de Seibersdorf

    Energy Technology Data Exchange (ETDEWEB)

    Weidinger, N.; Kaindl, K. [Institute Of Biology And Agriculture, Reactor Centre, Seibersdorf (Austria)

    1966-11-15

    ' sterzhnej s vneshnej dlinoj v 250 mm mogut vvodit'sja poodinochke s pomoshh'ju kabelja tipa Telefleks. Oni mogut byt' ostanovleny v ljubom zhelaemom polozhenii, izmerjaemom po otnosheniju k vhodu v kameru. Dlja'nabljudenija za opytami ustanovlen monokuljarnyj periskop. Pomeshhenie kontroliruetsja pri temperature ot -18sS do +35 Degree-Sign S s tochnost'ju {+-}1 Degree-Sign S. Cherez betonnyj jekran prohodjat neskol'ko trubok diametrom do 300 mm, kotorye sluzhat dlja propuskanija trosov i jeksperimental'nyh trubok. Vremja obluchenija mozhet ustanavlivat'sja s pomoshh'ju otdel'nogo tajmera, pozvoljajushhego ubirat' istochniki v nerabochee polozhenie posle obluchenija, ili zhe naoborot vydvigat' ih dlja obluchenija posle prohozhdenija opredelennogo promezhutka vremeni, v zavisimosti ot trebovanij. Vsja ustanovka avtomaticheski kontroliruetsja sistemoj blokirovki. Sistema radiacionnyh detektorov i mehanicheskih zaporov obespechivaet maksimal'nuju bezopasnost' ustanovki v sluchae avarii. Vse zazhnye bloki pitajutsja batareej s bufernym ustrojstvom s tem chtoby, dazhe v sluchae proboja, obespechit' nepreryvnuju rabotu. V sluchae vyhoda iz stroja vazhnyh komponentov ustanovki ili nepredvidennyh avarij srabatyvaet sistema signalizacii. V sluchae chrezvychajnoj opasnosti jeta sistema nemedlenno ubiraet istochniki v nerabochee polozhenie, a v sluchae nebol'shoj opasnosti - podnimaet ih naverh, posle chego operator reshaet, prodolzhat' obluchenie ili net. (author)

  4. The Performance of Major Plant Items at Calder Hall; Fonctionnement des elements principaux de la centrale de Calder Hall; Kharakteristika osnovnykh uzlov ustanovki v Kolder-Kholle; Rendimiento de los principales elementos de la central de Calder Hall

    Energy Technology Data Exchange (ETDEWEB)

    Desbruslais, E. L. [United Kingdom Atomic Energy Authority, Seascale, Cumberland (United Kingdom)

    1963-10-15

    . Opravdannoj yavlyaetsya ustanovka sdvoennogo vspomogatel'nogo oborudovaniya vmeste s ob{sup e}dineniem parovoj i vodnoj sistem. Oborudovanie B.C.D.G. okazalos' v vysshej stepeni udovletvoritel'nym. Vvidu togo, chto chuvstvitel'nost' gruppy kanalov vyshe chem neobkhodimo, v nastoyashchee vremya planirugtsya izmeneniya s tsel' ukorocheniya tsiklov za schet nekotoroj chuvstvitel'nosti. Obsuzhdayutsya meropriyatiya po pereoborudovaniyu sistemy podachi ehnergii dlya priborov reaktora i konturov bezopasnosti. Rekomenduyutsya klassifikatsiya stepeni opasnosti i vazhnosti i ustrojstvo po pervomu vyklyucheniyu reaktora. Vyyasnyaetsya neobkhodimost' imet' sistemu s dvumya zashchitnymi liniyami i ustanavlivat' tri ili bolee takikh linij. Statistika- pokazala polnuyu nadezhnost' oborudovaniya registratsii dannykh. Opravdyvaetsya neobkhodimost' bol'shoj standartizatsii oborudovaniya po peregruzke topliva. Ispol'zovanie spetsial'nykh ballonov i spetsial'nogo oborudovaniya po razgruzke trebuet mnogo vremeni, i ot ehtogo sleduet otkazat'sya. Opisyvayutsya izmeneniya/ vnesennye v mekhanizmy po zagruzke/razgruzke i vo vspomogatel'nuyu ustanovku. Podcherkivaetsya neobkhodimost' tshchatel'noj obrabotki topliva vo vremya zagruzki. Primenenie televizionnykh kamer v toplivnykh kanalakh i spetsial'nykh zakhvatov pozvolilo sokratit' vremya razgruzki. Nebol'shie neispravnosti otmecheny lish' pri ehkspluatatsii slozhnykh mekhanizmov upravlyayushchikh sterzhnej i sootvetstvuyushchego oborudovaniya po kontrolyu. Naskol'ko ehto vozmozhno, osnovnye sistemy upravleniya ustanovki dolzhny byt' tsentralizovany, i osnovnye tsentry upravleniya i uzly upravleniya ustanovki dolzhny byt' zashchishcheny ot sluchajnogo povrezhdeniya pri obluchenii vneshnimi istochnikami. Priznayutsya neobkhodimymi avtomaticheskie puskovoe i parallel'noe ustrojstva dlya avarijnoj dizel'noj ustanovki, odnako ustanovka mogla by byt' tsentralizovana s pol'zoj dlya dela. (author)

  5. The Control of Fast Reactors: Current Methods and Future Prospects; Controle des Reacteurs a Neutrons Rapides. Methodes Actuelles et Perspectives d'Avenir; Upravlenie reaktorami na bystrykh nejtronakh. sushchestvuyushchie metody i dal'nejshie perspektivy; Control de Reactores Rapidos: Metodos Actuales y Perspectivas

    Energy Technology Data Exchange (ETDEWEB)

    Loewenstein, W. B. [Argonne National Laboratory, IL (United States)

    1964-06-15

    efectividad de los mecanismos de control han evolucionado desde evaluaciones poco precisas hasta calculos muy fidedignos confirmados experimentalmente en conjuntos criticos. El autor describe los resultados experimentales y las tecnicas analiticas, que suelen ser seguras. Los experimentos criticos que precedieron la construccion de los actuales modelos de reactores de neutrones rapidos comprendieron muchas investigaciones sobre la efectividad de sus mecanismos de control y experimentos marginales para sistemas perfeccionados en los que el cuerpo tiene un volumen mayor. El autor cita algunos estudios analiticos provisionales de los que se puede deducir que no habra necesidad de efectuar en lo sucesivo investigaciones experimentales detalladas en maquetas. (author) [Russian] Obsuzhdajutsja prakticheskie aspekty obespechenija sootvetstvujushhej reaktivnosti dlja upravlenija reaktorami na bystryh nejtronah, kotorye sushhestvenno otlichajutsja ot analogichnyh aspektov pri osushhestvlenii kontrolja sistem teplovyh nejtronov. Jeti razlichija vyzvany glavnym obrazom blagodarja nebol'shim sechenijam na bystryh nejtronah. V sistemah na bystryh nejtronah otsutstvujut sil'nye poglotiteli nejtronov. V rezul'tate jetogo takie sil'nye poglotiteli nejtronov v teplovyh reaktorah, kak produkty raspada (naprimer He i Zt)trebujut znachitel'no men'she reaktivnosti na ih kompensaciju, chem poterja reaktivnosti, vyzvannaja deleniem i zahvatom rasshhepljajushhihsja materialov. Poskol'ku atomnye sechenija bystrogo spektra dovol'no maly po sravneniju s sechenijami dlja teplovyh nejtronov atomnaja plotnost' materiala igraet vazhnuju rol' pri vybore materialov dlja regulirujushhih sterzhnej. Opisyvajutsja sushhestvujushhie tipy kontrol'nyh mehanizmov reaktorov na bystryh nejtronah. Jeti sposoby napravleny na vozmozhnost' ispol'zovanija, tam, gde jeto priemlemo,, kontrolja za utechkoj nejtronov. Kogda takoj kontrol' prakticheski neosushhestvim, to pri menjaetsja kontrol' s pomoshh'ju peredvizhenija