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The transient currents and stationary current-voltage characteristics of Ta-Ta2Q5-MnO2 systems with negative tantalum polarity are considered. It is shown that in this case space-charge limited currents flow through the system with an exponential distribution of the trap energy when there are deep donor centers. In the intensefield region the Poole-Frenkel effect begins to have an important effect on the injection currents. An appropriate theory is developed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 94–97, May, 1981. 相似文献
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Electrical breakdown under dc stress is examined for anodic oxide films on tantalum and zirconium of 100–5000 Å thickness. It is found that the strength is greater for the thinner films, which points to an ionization breakdown mechanism. It is considered that allowance must be made for electron traps and formation of a negative space charge in discussing the breakdown of amorphous oxide films. 相似文献
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The current-field temperature relationships of the Ta-Ta2O5-MnO2 system are studied when the tantalum has positive polarity. It is demonstrated that the conductivity of such systems is determined by the Poole-Frenkel effect (PFE) for partially compensated donors. We compare our results with previous results [9]. A theory of the PFE is developed for a model which includes traps with an exponential energy distribution; acceptors, and deep discrete donors.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 3–6, October, 1981. 相似文献
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Eremeev A. V. Krutius O. N. Mishnev A. F. Bleidelis Ya. Ya. Liepin'sh É. É. Odynets A. G. Berzinya D. A. Kimenis A. A. 《Chemistry of Heterocyclic Compounds》1984,20(10):1108-1113
It has been found that the reaction of - and -amino alcohols with methyl 1,2-dibromopropionate results in the formation of esters of 1-(hydroxyalkyl)aziridine-2-carboxylic acids or 1-aza-4-oxabicyclo[4.1.0]pentan-5-ones, depending on the nature of the original reactants. An x-ray structural analysis of this new bicyclic system has been carried out. The hepatoprotector activity of the new compounds has been studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1349–1354, October, 1984. 相似文献
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Ievgen V. Odynets Dr. Artem A. Babaryk Vyacheslav N. Baumer Nikolay S. Slobodyanik Oleg V. Shiskin 《无机化学与普通化学杂志》2011,637(11):1511-1515
Potassium‐containing zirconium(IV)/titanium(IV) tantalum(V) oxides, K3TiTa7O21 ( 1 ) and K3ZrTa7O21 ( 2 ), of K3Nb8O21‐type of compounds are afforded from potassium‐molybdate flux. Both compounds crystallize in the hexagonal space group P63/mcm (no. 193) with a = 908.69(2), c = 1202.83(7) pm and c/a = 1.324 (Z = 2) for 1 and a = 913.30(3), c = 1219.21(6) pm and c/a = 1.335 (Z = 2) for 2 , respectively. The Structural motif of [MTa7O21]3– (M = Ti4+ or Zr4+) consists of edge‐shared (M,Ta)6O24‐units that are similar to corner‐sharing Ta6O27 units of synthetic soro‐silicate K3Ta3Si2O13 and double borate K3Ta3B2O12. The solid state bandgap measurements revealed that calculated values (3.26 eV for K3TiTa7O21 and 3.14 eV for K3ZrTa7O21) are dependent on aperture of Ta–O–Ta bond angle as it was previously shown for perovskite‐type tantalate photocatalysts. 相似文献
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