[en] A new approach to the problem of production of HTSC compounds and phases is proposed. Two new HTSC phases with Tc=30-45 K are obtained. Problems of development of new HTSC compounds and possible ways for solving the problems are considered

No abstract available

[en] According to the earlier publications, coexistence of superconductive and ferroelectrical properties in oxides, and availability of relationship between them are considered. The analysis of the data on Cu-containing perovskites has shown that HTSCs combine superconductive and ferroelectric properties, that can provide for unique aplications of these materials in future. 18 refs

[en] Single crystals of BaPbO₃ (I)--BaBiO₃ (II) solid solutions were grown from the melt. Comprehensive investigations were made of their structure, dielectric properties, and conductivity. The composition dependences of the dielectric phase transitions were determined for solid solutions throughout the system and the corresponding dependences were obtained for superconducting transitions in solid solutions with 0--35 mol.% II. A composition correlation was observed between the dielectric and superconducting phase transitions

[en] Superconducting ceramics of YBa₂(Cu_x⁺Cu_1-x²⁺)₃O_7-delta composition with usage of one-valent copper in the form Cu₂O and two-valent copper in the form CuO is synthesized. It is established that the increased temperature of transition beginning Tb=100.5 K at delta T=4.5 K have the ceramic samples obtained from charge with x=0.25-0.30. When using Cu₂O as initial component is reduced the total time of heat treatment without aggravating ceramics quality. The conclusion permits to recommend Cu₂O using in synthesis of copper-containing ceramics HTSC of the YBa₂Cu₃O_7-delta type

No abstract available

[en] Mass spectrometric study of the composition of neutral and charged products formed during laser evaporation of HTSC ceramics and kinetics of their formation is carried out. It is shown that the main way of mass transfer, when YBa₂Cu₃O_7-δ ceramics is exposed to 1.06 and 0.266 μm laser radiation resulting in its evaporation, is formation of neutral products such as atoms and oxides of metals (except for CuO) along with formation of some amount of positive ions. Oxygen releases slowly and more intensively, which can affect the deposited substance stoichiometry. 3 refs

[en] Short note

No abstract available

[en] Ceramic specimens of solid solutions of the SrTiO₃-BaTiO₃, SrTiO₃-CaTiO₃ systems are synthesized. X-ray phase analysis and measurements of their dielectric properties in 4.2-200 K range are carried out. Exceptea expressed maximum permittivity wkly expressed anomalies are found at temperature epsilon(T) dependence, their concentra tional dependence is studied. It is established that Curie point of strontium titanate is in the range of 100-112. 5 K and that pure SrTiO₃, besides the high-temperature phase transition, has a series of low-temperature phase transitions, the position of which, probably, obeys the dependence Tsub(ptt)=Tsub(0)N (N-an integer, T₀=12.5 K)