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71.
Pavel Diko Renáta Pagáčová Katarína Zmorayová Veronika Kuchárová Liudmila Vojtková Vitaliy Antal Viktor Kavečanský 《Journal of the American Ceramic Society》2021,104(2):740-752
Barium cerate (BaCeO3) is one of the possible additions to bulk YBa2Cu3O7 single-grain superconductors to suppress the growth of Y2BaCuO5 (Y211) particles. This paper investigates the synthesis of barium cerate powder and its use in YBa2Cu3O7 bulk superconductors. Crystalline barium cerate was synthesized by solid-state reaction, by co-precipitation of oxalates and by sol-gel method. Final calcination was held in air or in vacuum. It is shown that the most efficient in refining Y211 is nanocrystalline barium cerate prepared by sol-gel method calcined in vacuum. The effective refinement of Y211 particles occurred over the entire interval of nanocrystalline BaCeO3 addition from 0.38 to 1.90 wt%. The optimal concentration of nanosize barium cerate was determined, microstructure and superconducting properties were characterized. The effect of Y211 content on trapped field in YBCO bulks with addition of nanocrystalline barium cerate is shown. 相似文献
72.
Semiconductors - Graphitic carbon nitride was synthesized via thermolysis of urea and then ultrasonic exfoliated from colloidal solution to obtain phase pure ultrafine powder of g-C3N4. It was... 相似文献
73.
74.
T. P. Zakharova 《Strength of Materials》1974,6(4):415-421
Conclusions The distribution of the logarithm of the number of, cycles to destruction (logN) at a constant amplitude of the variable stress -1, in accordance with the proposed hypothesis about independence of the two fatigue damage mechanisms being realized in the metal, can be represented by a mixture of two normal distributions with the weighting coefficients P1 and P2. Processing of results of fatigue tests, by means of separating the two constituents, from an empirical distribution, is expedient in three cases: 1) for moderlate probabilities 0.05
-1 into the region of large life values in the case of probabilities of failure P0.05; 3) for extrapolation of experimental data with respect to log N into the region of small and very small probabilities P0.01.Translated from Problemy Prochnosti, No. 4, pp. 17–23, April, 1974. 相似文献
75.
N. N. Zakharova I. D. Zenkov A. N. Sokira L. A. Volkov M. P. Zverev 《Fibre Chemistry》1989,20(3):164-166
Conclusions Special features of spinning a fibre by the wet method from a copolymer based on acrylonitrile and sodium methallylsulfonate which are connected with dissociation and solvation of the sulfonate groups have been examined.It has been found that, to obtain a fibre with satisfactory physico-mechanical properties which assure processing into textile articles from a sulfonate-containing copolymer, it is necessary to carry out the spinning either into nonaqueous baths or into aqueous baths which contain lyophilic salts.Translated from Khimicheskie Volokna, No. 3, pp. 10–12, May–June, 1988. 相似文献
76.
M. A. Elistratova I. B. Zakharova N. M. Romanov V. Yu. Panevin O. E. Kvyatkovskii 《Semiconductors》2016,50(9):1191-1197
The results of studies of thin composite films of zinc and copper tetraphenylporphyrins with different fractions of fullerene C60 are reported. The photoluminescence spectra are recorded, and the composition and surface morphology are analyzed by means of scanning electron microscopy. The results show a difference in the structure of films with two types of metals (Zn, Cu) entering into the complex of the porphyrin macrocycle. An additional long-wavelength photoluminescence band at 1.4 eV is detected for the first time, which is evidence of the formation of ZnTPP–C60 molecular complexes from a gas-dynamic vapor flow upon condensation. In CuTPP thin films, the processes of self-assembly into nanowires 20 nm in diameter and up to 50 µm in length and the formation of nanoheterojunctions upon the addition of fullerene C60 are observed. Quantum-chemical calculations in the context of density-functional theory are carried out to interpret the experimental data. 相似文献
77.
Igor Bychkov Galina Baydakova Alexandra Filatova Ochir Migiaev Andrey Marakhonov Nataliya Pechatnikova Ekaterina Pomerantseva Fedor Konovalov Maria Ampleeva Vladimir Kaimonov Mikhail Skoblov Ekaterina Zakharova 《International journal of molecular sciences》2021,22(19)
Pompe disease (OMIM#232300) is an autosomal recessive lysosomal storage disorder caused by mutations in the GAA gene. According to public mutation databases, more than 679 pathogenic variants have been described in GAA, none of which are associated with mobile genetic elements. In this article, we report a novel molecular genetic cause of Pompe disease, which could be hardly detected using routine molecular genetic analysis. Whole genome sequencing followed by comprehensive functional analysis allowed us to discover and characterize a complex mobile genetic element insertion deep in the intron 15 of the GAA gene in a patient with infantile onset Pompe disease. 相似文献
78.
Nikolay A. Tsvetkov Liudmila L. Larina Oleg Shevaleevskiy Essam A. Al‐Ammar Byung Tae Ahn 《Progress in Photovoltaics: Research and Applications》2012,20(7):904-911
A barrier layer of undoped TiO2 was deposited on the Nb‐doped TiO2 electrode to suppress the recombination at the Nb‐doped TiO2/dye–electrolyte interface for highly efficient dye‐sensitized solar cells (DSCs). The Nb content in TiO2 was varied in a range of 0.7–3.5 mol% to modify the TiO2 energy‐band structure. Nb‐doped TiO2/dye interfaces were characterized by a combination of ultraviolet photoemission spectroscopy and optical absorption spectroscopy measurements, allowing the determination of the conduction band minimum (CBM) of the TiO2 electrode and the lowest unoccupied molecular orbital of the N719 dye. The lowering of TiO2 CBM by Nb doping induced the increase in short‐circuit current of DSCs. However, open‐circuit voltage and fill factor are decreased, and this result was ascribed to the enhanced recombination at the Nb‐doped TiO2/dye–electrolyte interface. The effect of doping on charge transport in DSCs was analyzed using electrochemical impedance spectroscopy. We have shown that by introducing of TiO2 barrier layer, the Nb doping content, which results in DSC highest efficiency, can be increased because of the suppression of the dopant‐induced recombination. The energy conversion efficiency of the solar cells increased from 7.8% to 9.0% when undoped TiO2 electrode is replaced with electrode doped with 2.7 mol% of Nb because of the improvement of the electron injection and collection efficiencies. The correlation between the electronic structure of the TiO2 electrode, charge transfer characteristics, and photovoltaic parameters of DSCs is discussed. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
79.
80.
G. T. Vigant A. B. Énglin N. N. Zakharova I. V. Klimyuk 《Chemistry and Technology of Fuels and Oils》1991,27(5):244-248
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 5, 11–13, May, 1991. 相似文献