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The reactions of cobalt(II) nitrate or perchlorate with acetamide (AA) or carbamide (Ur) in an aqueous medium results in formation of coordination compounds [Co(Ur)4](NO3)2 (I), [Co(Ur)6](NO3)2 (II), [Co(AA)4(H2O)2](NO3)2 (III), [Co(AA)4(H2O)2](NO3)2∙2AA (IV), [Co(Ur)6](ClO4)2, (V), [Co(AA)4(H2O)2](ClO4)2 (VI), and [Co(AA)6](ClO4)2 (VII). The compositions of the isolated complexes are determined by physicochemical methods, and the crystal and molecular structures of compounds II, V, VI, and VII are solved. Specific features of the thermal behavior of all synthesized compounds in a wide temperature range are studied in detail. These compounds are shown to be used as precursors in the preparation of nanosized Co3O4 using self-propagating high-temperature synthesis. The catalytic activity of thus synthesized Co3O4 in the model epoxidation of allyl alcohol is studied. [ABSTRACT FROM AUTHOR]

Coordination compounds [Zn(H2O)4(Ur)2](NO3)2, [M(H2O)2(Ur)2(NO3)3] (M = Ce, Nd), and [Dy(H2O)(Ur)2(NO3)3] have been synthesized by the reaction of nitrates of zinc or rare earth elements with urea (Ur) in an aqueous solution. Their composition has been determined and structural features have been established using elemental analysis, IR spectroscopy, and X-ray diffraction analysis. For the zinc complex, a polymorphic transition has been found at 181 K. [ABSTRACT FROM AUTHOR]

In the rare-earth element nitrate (REE)–dimethylformamide (DMF)–water systems, which can be used to obtain nanosized REE oxides by solution combustion synthesis (SCS), the formation of coordination compounds [M(H2O)3(DMF)(NO3)3]·H2O (M = La–Pr) and [M(DMF)3(NO3)3] (M = Sm–Lu, Y) has been found. Using physicochemical methods of analysis (IR spectroscopy, X-ray powder diffraction, single-crystal X-ray diffraction, elemental analysis, thermogravimetric analysis, and differential scanning calorimetry), their composition has been determined and structural features have been established; thermolysis processes have been studied in a wide temperature range. It is shown that the final products of the decomposition of complex compounds are oxides of rare earth elements. [ABSTRACT FROM AUTHOR]

Reaction of scandium nitrate with carbamide (Ur) in aqueous solution has been studied and two previously unknown coordination compounds [Sc(H2O)(Ur)2(NO3)(μ-OH)2(NO3)(Ur)2(H2O)Sc](NO3)2 and [Sc(H2O)(Ur)4(NO3)2]NO3 have been revealed. Procedures have been developed for the synthesis of these compounds. The compounds have been studied by physicochemical methods (IR spectroscopy, X-ray powder difffraction, X-ray single-crystal diffraction, elemental analysis, thermogravimetric analysis, and differential scanning calorimetry), their composition and structure have been established. Thermolysis in wide temperature range and phase composition of thermal degradation products have been studied. It has been shown that the isolated complexes can be used for the synthesis of nanosized (20–50 nm) scandium oxide suitable as a component of modern functional materials. [ABSTRACT FROM AUTHOR]

The method of mechanical treatment of thermoelectric materials Bi2Te2.8Se0.2 (0.14 wt % of CdCl2), Bi0.5Sb1.5Te3 (2 wt % of Te and 0.14 wt % of TeI4), PbTe (0.2 wt % of PbI2 and 0.3 wt % of Ni), and GeTe (7.4 wt % of Bi) with low microhardness (25–70 kg/mm2) is proposed. The average surface roughness about 20 nm was obtained. The methods and regimes of surface cleaning before the deposition of thin films were determined. The thin-film Ni contacts were formed by ion-plasma deposition on the samples of thermoelectric materials with different surface roughness. The adhesion strength of contacts was measured by the method of uniform normal tear. The study results allow us to determine the required level of mechanical treatment of surface, which depends on the thickness of the formed thin films. It was shown that value of the adhesion strength of Ni contacts formed to the thermoelectric materials is more than 11.5 MPa. This corresponds to criterion of mechanical strength of contacts in the thermoelements. As study result of the electrical resistance, it was found that the contact resistance of Ni films formed on thermoelectric materials is less than 10–9 Ω m2. [ABSTRACT FROM AUTHOR]

Electronic thermostating components are developed for automatic control of heat-transfer agent fl ow in heating systems in accordance with a specified program and for regulating the temperature in heated places. Original equipment and programming solutions are proposed for electronic thermostating components and the algorithm for their operation is optimized. [ABSTRACT FROM AUTHOR]

An intelligent system and its electron components are developed that implement an innovative method for measuring individual heat consumption. For the intelligent system and its electron components, original design-technological, circuit, hardware, and software solutions are proposed. The methods and mathematical models for evaluating individual heat consumption are developed and validated. [ABSTRACT FROM AUTHOR]

A method, measurement system, and hardware and software facilities are developed for studying the reliability of data reception and signal level in radio channels. This method can be used to test the wireless communication channels employed in smart devices for data measurement and transmission during manufacture. Studies are made of the wireless communication channels of batches of commercially produced smart devices. The dependence of the loss probability for a packet of data on the radio signal level is determined. [ABSTRACT FROM AUTHOR]

An automated system for investigating and calibrating temperature measuring instruments with a wireless interface is proposed and constructed. The system is designed for the remote monitoring of temperature and the storage and transmission of data over a radio channel. A procedure for calculating the data of the measuring instruments and a hardware-software system for performing this automatically are developed. [ABSTRACT FROM AUTHOR]

Methods and original hardware - software facilities for metering the individual consumption of heat energy, based on an intelligent system for monitoring power supplies, are proposed. [ABSTRACT FROM AUTHOR]