A study of the mechanism of certain heterogeneous catalytic processes using C{sup 14}-labelled compounds; Utilisation de composes marques au carbone-14 pour l'etude du mecanisme de certains processus catalytiques heterogenes; Issledovanie mekhanizma nekotorykh geterogenno-kataliticheskikh protsessov s primeneniem soedinenij, mechennykh uglerodom-14; Estudio del mecanismo de algunos procesos de catalisis heterogenea con ayuda de compuestos marcados con carbono-14

Energy Technology Data Exchange (ETDEWEB)

Isagulyants, G V; Balandin, A A

1962-03-15

An investigation is made of the method of calculating individual phase velocities for parallel, consecutive and parallel-consecutive reactions from kinetic data obtained by the use of labelled atoms. The method is used for calculating individual phase velocities in the decomposition reaction of isopropyl alcohol into vanadium trioxides, dehydrogenations of butane-butylene mixtures and dehydrations of ethyl alcohol. Compounds containing C{sup 14} were used in this study. (author) [French] Le memoire expose une methode par laquelle on calcule les vitesses a differents stades dans les reactions paralleles, consecutives et paralleles-consecutives en se servant de donnees cinetiques obtenues par l'utilisation d'atomes indicateurs. Cette methode est utilisee pour le calcul des vitesses a differents stades de la decomposition de l'alcool isopropylique par le trioxyde de vanadium, de la deshydrogenation des melanges butane-butylene et de la deshydratation de l'alcool ethylique. Pour ces travaux, on a utilise des composes contenant du carbone-14. (author) [Spanish] Se describe un metodo de calculo de las velocidades correspondientes a las distintas etapas de una serie de reacciones paralelas, consecutivas y paralelo-consecutivas, partiendo de datos cineticos obtenidos mediante atomos marcados. El metodo se aplica a la determinacion de las velocidades de las reacciones de descomposicion del alcohol isopropilico por el trioxido de vanadio, de deshidrogenacion de mezclas de butano y buteno y de deshidratacion del alcohol etilico. El trabajo se llevo a cabo con ayuda de compuestos marcados con carbono-14. (author) [Russian] Rassmotren metod rascheta skorostej otdel'nykh stadij dlya parallel'nykh, konsekutivnykh i parallel'no-konsekutivnykh reaktsij, iskhodya iz kineticheskikh dannykh, poluchennykh s primeneniem mechenykh atomov. Metod primenen k raschetu skorostej otdel'nykh stadij v reaktsii razlozheniya izopropilovogo spirta na trekhokisi vanadiya, degidrogenizatsii butan

Low temperature grown ZnO@TiO{sub 2} core shell nanorod arrays for dye sensitized solar cell application

Energy Technology Data Exchange (ETDEWEB)

Goh, Gregory Kia Liang [Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology, and Research), 3 Research Link, 117602 Singapore (Singapore); Le, Hong Quang, E-mail: lehq@imre.a-star.edu.sg [Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology, and Research), 3 Research Link, 117602 Singapore (Singapore); Huang, Tang Jiao; Hui, Benjamin Tan Tiong [Department of Materials Science and Engineering (DMSE), Faculty of Engineering National University of Singapore (NUS) BLK E3A, #04-10, 7 Engineering Drive 1, Singapore 117574 (Singapore)

2014-06-01

High aspect ratio ZnO nanorod arrays were synthesized on fluorine-doped tin oxide glasses via a low temperature solution method. By adjusting the growth condition and adding polyethylenimine, ZnO nanorod arrays with tunable length were successfully achieved. The ZnO@TiO{sub 2} core shells structures were realized by a fast growth method of immersion into a (NH{sub 4}){sub 2}·TiF{sub 6} solution. Transmission electron microscopy, X-ray Diffraction and energy dispersive X-ray measurements all confirmed the existence of a titania shell uniformly covering the ZnO nanorod's surface. Results of solar cell testing showed that addition of a TiO{sub 2} shell to the ZnO nanorod significantly increased short circuit current (from 4.2 to 5.2 mA/cm{sup 2}), open circuit voltage (from 0.6 V to 0.8 V) and fill factor (from 42.8% to 73.02%). The overall cell efficiency jumped from 1.1% for bare ZnO nanorod to 3.03% for a ZnO@TiO{sub 2} core shell structured solar cell with a 18–22 nm shell thickness, a nearly threefold increase. - Graphical abstract: The synthesis process of coating TiO{sub 2} shell onto ZnO nanorod core is shown schematically. A thin, uniform, and conformal shell had been grown on the surface of the ZnO core after immersing in the (NH{sub 4}){sub 2}·TiF{sub 6} solution for 5–15 min. - Highlights: • ZnO@TiO{sub 2} core shell nanorod has been grown on FTO substrate using low temperature solution method. • TEM, XRD, EDX results confirmed the existing of titana shell, uniformly covered rod's surface. • TiO{sub 2} shell suppressed recombination, demonstrated significant enhancement in cell's efficiency. • Core shell DSSC's efficiency achieved as high as 3.03%, 3 times higher than that of ZnO nanorods.

Changes of vitamin C content in celery and parsley herb after processing

Directory of Open Access Journals (Sweden)

Magdaléna Valšíková

2016-12-01

Full Text Available Humans and other primates have lost the ability to synthesize vitamin C and therefore the only source is diet. Vitamin C or ascorbic acid has labile nature, it is removed or destroyed in specific degree immediately after harvest, but storage and post - harvest processing also contribute to its degradation. The aim of work was to determine the vitamin C content in the herb of selected celery and parsley varieties in dependence on chosen postharvest processing and to compare it with fresh herb. There were chosen five bulb forms varieties of celery (Apium graveolens - Makara, Ilonaa, Hegy Köi, Talar and Diamant. In case of parsley (Petroselinum crispum there were evaluated one variety of curly parsley, one variety of herb parsley - Petra, and five varieties of root parsley - Lenka, Eagle, Ginate D´Italia, Titana and Arat. Every variety was harvested in three terms, followed by vitamin C content estimation in fresh herb, after drying and after freezing. The content of vitamin C was estimated by HPLC method by the help of liquid chromatograph with UV detector. There was found the significant difference in content of vitamin C in parsley as well as in celery when comparing the fresh herb with herbs after post - harvest processes - drying (by air circulation in laboratory hall and freezing. After processing of herbs in both observed species the vitamin C content decreased, in case of freezing it was about 65% (celery and 61% (parsley, after drying about 86% (celery and 82% (parsley in comparison with fresh herb. The effect of processing played more important role in influencing of vitamin C content than variety in case of both selected species. For using of celery and parsley not only as culinary herb, but as a notable source of ascorbic acid it is the most important fresh herb intake.  Normal 0 21 false false false EN-GB X-NONE X-NONE

Determination of P, Cu, Cr, Va and Ti in samples of welded joint No.4 of Kozloduy-1 reactor pressure vessel; Opredelenie soderzhanya fosfora, medi, nikelya, khroma, vanadya i titana v struzhkakh 4 shva 1 bloka AEhS `Kozloduy`

Energy Technology Data Exchange (ETDEWEB)

Taskaev, E [Kombinat Atomna Energetika, Kozloduj (Bulgaria); Penev, I; Taskaeva, M [Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. za Yadrena Izsledvaniya i Yadrena Energetika; Aleksieva, L [Sofia Univ. (Bulgaria); Tsokov, P [Kombinat Atomna Energetika, Kozloduj (Bulgaria)

1996-12-31

An analysis of reactor steel composition has been carried out in 1989 in order to determine metal embrittlement. The samples consist of shavings taken at 3-4 mm depth from the 4-th welded joint of Unit 1 of the Kozloduy NPP. The shavings have been gradually dissolved in a mixture of acids and the solution evaporated. Quantitative analysis has been carried out by spectrophotometry and by ICP emission spectroscopy. The following element concentrations have been found: P - from 0.0462 to 0.052% by weight; Ni - 0.25 - 0.26% (passport data 0.29%); Cr - 1.47 - 1.54 (passport 1.58%); V - 0.1% (passport 0.15%); Cu - 0.11-0.13% (passport 0.12); Ti - 0.002. The data have been used to calculate metal embrittlement. 4 refs., 8 tabs.

Diffusion, recrystallization and phase transformations; Diffusion, recristallisation et changements de phase; Diffuziya, rekristallizatsiya i fazovye prevrashcheniya; Difusion, recristalizacion y cambios de fase

Energy Technology Data Exchange (ETDEWEB)

Bokshtejn, S Z; Gubareva, M A; Kishkin, S T; Moroz, L M

1962-01-15

rekristallizatsii, a takzhe posle polimorfnogo {alpha} {r_reversible} {gamma} prevrascheniya, atomy granits iskhodnykh zeren ne smeshchayutsya na znachitel'nye rasstoyaniya. Analogichno, atomy primesi (radioaktivnyj uglerod), raspolozhennye na granitsakh iskhodnogo zerna, ne perekhodyat na granitsy novykh zeren rekristallizovannogo metalla. V otlichie ot ehtogo plasticheskaya deformatsiya soprovozhdaetsya znachitel'nym peremeshcheniem atomov, raspolozhennykh na granitse zerna. Poluchennye dannye pokazyvayut, chto peremeshchenie granits zeren pri rekristallizatsii i pri posleduyushchem roste zeren svyazano s nekotorym spetsificheskim mekhanizmom, otlichnym ot obychnogo diffuzionnogo. Pokazano, chto strukturnye izmeneniya, protekayushchie v splavakh pri vysokikh temperaturakh, mogut izmenyat' skorost' protsessov samodiffuzii i geterodiffuzii. V rezul'tate issledovaniya diffuzionnykh protsessov v titane i ego splavakh v zavisimosti ot polimorfnogo sostoyaniya ustanovleno, chto skorost' protsessa v razlichnykh kristallicheskikh modifikatsiyakh titana sil'no otlichaetsya. EHtim snimaetsya sushchestvovavshee protivorechie mezhdu vysokoj temperaturoj plavleniya titana i otnositel'no nizkoj ehnergiej aktivatsii protsessa diffuzii v titane. (author)

The Use of Ionizing Radiation in the Vulcanization of Silicon Rubber; Utilisation des radiations ionisantes pour la vulcanisation du caoutchouc au silicone; Ispol'zovanie ioniziruyushchikh izluchenij dlya vulkanizatsii silikonovogo kauchuka; Empleo de las radiaciones ionizantes en la vulcanizacion del caucho de siliconas

Energy Technology Data Exchange (ETDEWEB)

Kuzminsky, A S; Nikitina, T S; Oksentevich, L A [Rubber Research Institute, Moscow, Union of Soviet Socialist Republics (Russian Federation)

1960-07-15

temperaturas (150{sup o}, 200{sup o} y 250{sup o}). La irradiacion permite disminuir la temperatura de vulcanizacion y prescindir de un almacenamiento prolongado a temperatura regulada, que de otro modo es necesario despues de la vulcanizacion. El negro de humo puede utilizarse como material de carga para el caucho vulcanizado con arreglo al nuevo metodo. Los autores llegan a la conclusion de que el empleo de las radiaciones ionizantes se traduce en una simplificacion de la tecnologia de la vulcanizacion del caucho de siliconas y en un mejoramiento de las propiedades de los productos obtenidos. (author) [Russian] Osnovnaya tsel' raboty - podrobnoe izuchenie svojstv materialov, poluchaemykh v rezul'tate oblucheniya smesej polidimetil-siloksanovogo kauchuka s razlichnymi napolnitelyami (spetsial'naya kremnekislota, dvuokis' titana, kanal'naya, pechnaya i lampovaya sazha). Obluchenie provodilos' na moshchnoj rentgenovskoj ustanovke i na istochnike {gamma}-izlucheniya So{sup 60} aktivnost'yu 20 000 g-ehkv. radiya. Otsenena otnositel'naya skorost' obrazovaniya prostranstvennoj setki vulkanizatov (po velichine ravnovesnogo modulya i maksimal'noj stepeni nabukhaniya v benzole). Rassmotreno izmenenie soprotivleniya razryvu i otnositel'nogo udlineniya v protsesse oblucheniya. Vybrany optimal'nye rezhimy vulkanizatsii i opredeleny osnovnye fiziko-mekhanicheskie pokazateli vulkanizatov. Issledovano izmenenie svojstv radiatsionnykh vulkanizatov v protsesse teplovogo stareniya pri razlichnykh temperaturakh (150, 200 i 250{sup o}). Radiatsionnaya vulkanizatsiya isklyuchaet neobkhodimost ' provedeniya protsessa pri vysokikh temperaturakh i dlitel'noe termostatirovanie posle vulkanizatsii . Novyj sposob vulkanizatsii pozvolyaet primenyat' v kachestve napolnitelej uglerodnye sazhi. Ispol'zovanie ioniziruyushchikh izluchenij pozvolyaet uprostit' tekhnologiyu vulkanizatsii silikonovogo kauchuka i uluchshit' svojstva vulkanizatov. (author)

On the Behaviour of Radioisotopes Incorporated in Glass Blocks; Le Comportement des Radioisotopes Vitrifies; O Povedenii Radioaktivnyh Izotopov, Lokalizovannyh v Steklovidnyh Blokah; Comportamiento de los Radioisotopos Vitrificados

Energy Technology Data Exchange (ETDEWEB)

Zimakov, P. V.; Kulichenko, V. V.; Duhovich, F. S.; Salamatmn, B. A.

1963-02-15

steklovidnyh blokov, kak pravilo, vozrastaet posle ih progreva svyshe 400 Degree-Sign C. Otsjuda nezhelatel'no dopuskat' obrazovanija slishkom vysokih temperatur v mogil'nikah. Vysokaja plotnost' radiacii vysokoradioaktivnyh blokov takzhe-sil'no vlijaet na izmenenie struktury blokov, a sledovatel'no i prochnosti lokalizacii v nih oskolochnyh izotopov. Izmenenija takzhe idut v pervuju ochered' s poverhnosti pri kontakte s vneshnej sredoj (vozduh, voda). Vyshela- chivaemost' izotopov iz obluchaemyh blokov, kak pravilo, uvelichivaetsja. Jeksperimental'no ustanovlen povyshennyj vyhod radioaktivnyh izotopov s poverhnosti v gazovuju fazu dlja radioaktivnyh blokov. - Uchityvaja sovokupnost faktorov, dejstvujushhih na steklovidnye bloki v techenie dlitel'nogo vremeni, nuzhno putem special'nogo podbora ih himicheskogo sostava (fljusa) i''uslovij prigotovlenija,' obespechit' nadezhnuju lokalizaciju radioaktivnyh izotopov v zahoronennyh blokah; Osobyj interes v jetom otnoshenii predstavljaet primenenie dlja fljusovanija soedinenij titana. (author)

Use of Short-Lived Radioisotopes to Determine Impurities in Aluminium, Iron and Zirconium of Very High Purity; Dosages d'Elements par leurs Radioisotopes de Periodes Courtes Dans l'Analyse de Valuminium, du Fer et du Zirconium de Tres Hautes Puretes; ДОЗИРОВКА ЭЛЕМЕНТОВ С ПОМОЩЬЮ КОРОТКОЖИВУЩИХ РАДИОИЗОТОПОВ ПРИ АНАЛИЗЕ АЛХМИНИЯ, ЖЕЛЕЗА И ЦИРКОНИЯ ОЧЕНЬ ВЫСОКОЙ ЧИСТОТЫ; Determinacion Cuantitativa de Radioisotopos de Periodo Corto en los Analisis de Aluminio, Hierro y Circonio de Alta Pureza

Energy Technology Data Exchange (ETDEWEB)

Albert, Ph.; Deyris, M.; Deschamps, N.; Fournet, L. [Centre d' Etudes de Chimie Metallurgique, Vitry (France)

1963-03-15

sechenie zahvata i tol'ko {beta}-ijeluchenie). Odnako znanie koncentracii jetih jelementov v nashih metallah neobhodimo, tak kak v opredelennyh sluchajah oni predstavljajut soboj osnovnye primesi v metalle promyshlennogo naznachenija, kotoryj napravlen dlja ochishhenija. V inyh sluchajah mozhno stolknut'sja s bolee vysokim soderzhaniem primesej otdel'nyh iz jetih jelementov v ochishhennom metalle, nezheli v ishodnom. My otmetim, naprimer, znachenie dozirovki vanadija v aljuminii. Soderzhanie metalla v oblasti 'rasplavlennoj zony' byvaet poroj bolee vysokim, chem v metalle promyshlennogo naznachenija, i mozhet dostigat' do 30% obshej koncentracii dozirovannyh primesej. My opishem metody, issledovannye dlja provedenija kolichestvennyh analizov v razlichnyh sluchajah, s kotorymi my stolknulis'. Nashe izlozhenie kosnetsja v osnovnom opisanija analiza kremnija, hlora, broma i joda, provedennogo po obychnomu metodu radiohimicheskogo vydelenija posle obluchenija nejtronami. Kremnij byl podvergnut distilljacii v Si F{sub e}H{sub 2}. Hlor, brom i jod byli dozirovany na odnu probu dlja analiza. Pri obrabotke smesi galoidnyh solej azotnoj kislotoj jod i brom zameshhajutsja, i oba jelementa propuskajutsja s pomoshh'ju sil'noj vozdushnoj strui cherez neskol'ko poglotitelej: brom fiksiruetsja v rastvore sul'fita natrija, a jod poglashhaetsja v rastvore natrija. Hlor, kotoryj ne vytesnjaetsja iz azotnokislogo rastvora, vypadaet v sostave hloristogo serebra. Takim putem nami byla provedena dozimetrija hlora v jelektrolitnom zheleze i joda - v cirkonii 'Van Arkel'. S drugoj storony, my opishem takzhe metody, kotorye my izuchili dlja provedenija kolichestvennyh analizov na prisutstvie aljuminija, vanadija, magnija i titana v aljuminii, zheleze i cirkonii. jetih analizah sledy izyskivaemogo jelementa vydelilis' do obluchenija 'na neizotopnom nositele'; v nekotoryh sluchajah bystroe radiohimicheskoe ochishhenie proizvodilos' posle obluchenija. Predstavljaetsja vozmozhnym dozirovat' vanadij