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Sample records for cobaltite-gallates ndco1-xgaxo3 kristallicheskaya

  1. Electrical conductivity and thermo-EMF of cobaltite gallates LaCo_1_-_xGa_xO_3

    International Nuclear Information System (INIS)

    Lubinskij, N.N.; Shevchenko, S.V.; Bashkirov, L.A.; Petrov, G.S.; Slonskaya, S.V.

    2015-01-01

    It has been found that in LaCo_1_-_xGa_xO_3 system increase of the substitution degree x from 0 to 0,95 leads to the gradual electrical conductivity (σ) decrease. Within 300-1050 K temperature range for samples LaCo_1_-_xGa_xO_3 with x≤0,5 there are three linear parts on the curve lnσ - T"-"1, where electrical conductivity activation energies have been calculated for the low, intermediate and high temperature ranges. Electrical conductivity activation energy (E_A) for samples at different temperatures has been also estimated using derivatives d(lnσ)/d(T"-"1). The E_A temperature dependence for LaCo_1_-_xGa_xO_3 at 0≤x≤0,5 passes through a maximum that indicates the temperature for beginning of semiconductor-metal phase transition (T_E__A___m___a___x). It has been shown that the thermo-EMF coefficient (S) for LaCo_1_-_xGa_xO_3 (0,1≤x≤0,3) at room temperature is negative, increasing with temperature rising, going through zero at 435-530 K, reaching the maximum at 500-650 K and then dropping down. It has been established that the temperatures corresponding to the maximum S and E_A values are identical. (authors)

  2. Investigation of cascade regions of damage in alpha iron by a computer simulation method (crystal model). Issledovaniye kaskadnykh oblastey povrezhdeniya v. cap alpha. -zheleze metodom mashinnogo modelirovaniya (kristallicheskaya model)

    Energy Technology Data Exchange (ETDEWEB)

    Kevorkyan, Yu R

    1974-01-01

    A SPIKE program is used to study regions of structural damage that arise as a result of cascades of atomic collisions in single-crystal alpha iron. The model of the cascade process realized in the program uses a pair collision approximation and accounts for the influence of the crystal structure of the material. The following characteristics of regions of damage are found as a function of the energy of the primary knock-on atom: volume of the region, displacement effectiveness, size distribution of complexes of vacancies and injections. The results are compared with data in the literature. An appendix gives the text of the SPIKE program in FORTRAN.

  3. On the Conversion of UF{sub 6} to UO{sub 2}; Conversion de UF{sub 6} en UO{sub 2}; O prevrashchenii UF{sub 6} v UO{sub 2}; Transformacion del UF{sub 6} en UO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Kolar, D.; Slivnik, J.; Volavsek, B. [Jozef Stefan Nuclear Institute, Ljubljana, Yugoslavia (Slovenia)

    1963-11-15

    reduccion del hexafluoruro de uranio con amoniaco en fase gaseosa a 40 deg. C. Mediante una pirohidrolisis con vapor de agua e hidrogeno entre 500 y 600 deg. C, transformaron en dioxido de uranio el producto de grano muy fino retenido en precipitadores electricos. Por analisis termodiferencial y termogravimetrico observaron el desarrollo de la reaccion. Determinaron el fluor y el oxigeno contenidos en el dioxido de uranio y examinaron su estructura cristalina por analisis roentgenografico. Evaluaron diversas caracteristicas fisicoquimicas tales como el area superficial especifica, las dimensiones de las particulas y la densidad del polvo vibrado. A partir del polvo, prepararon pastillas prensadas y sinterizadas a 1350 deg. C. Obtuvieron densidades, variables segun las diversas condiciones de preparacion, que alcanzaron hasta el 94% del valor teorico. (author) [Russian] Vosstanovleniem geksaftorida urana ammiakom v gazovoj faze pri 40 deg. C byl poluchen kompleksnyj ammonij ftorid urana. Ehtot melkij poroshok uderzhivalsya v ehlektroosaditelyakh i perevodilsya v dvuokis' urana metodom pirogidrolieha vodyanymi parami i vodorodom pri temperature ot 500 do 600 deg. C. Khod reaktsii kontrolirovalsya metodom termicheskogo i termogravimetricheskogo analizov. V dvuokisi urana analiticheski opredelyalos' soderzhanie ftora i kisloroda, a kristallicheskaya struktura proveryalas' metodom rentgenovskogo analiza. Opredeleny nekotorye fiziko- khimicheskie' kharakteristiki , kak udel'naya poverkhnost', razmer chastits i konechnaya plotnost' poroshka. Iz poroshka pressovalis' tabletki, kotorye spekalis' pri 1350 deg. C. V zavisimosti ot razlichnykh uslovij izgotovleniya byli dostignuty plotnosti do 94% teoreticheskoj. (author)