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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]

A new concept for determining the individual heat consumption in the heating systems of the apartment houses, which was realized in the intellectual system, developed by authors, for controlling the individual heat consumption, is proposed. Concept is based on the use of virtual measuring channels, determined by the technology of intellectual precise temperature sensors and flow meters for heat carrier in heating systems. Configuration of measuring channels is determined by software means, and can be operatively changed during exploitation. Methods and mathematical models for the calculation of individual heat consumption were determined, including calculation and distribution of total house heat consumption. Design principle of intellectual system for controlling the individual heat consumption was determined. Original design solutions, and hardware and software means for electronic components were developed. System carries out direct measurements of heat consumption, and performs data reception and transmission from electronic measuring and controlling components using radio channel at frequencies of 434 or 868 MHz, then it is performing calculations and displaying results. Results of calculations in real measuring units are displayed on the local retranslator and apartment monitor. Exclusive feature of this concept is associated with the possibility of measuring of total house heat consumption. Estimation of confidence limits of systematic measurement error of the individual heat consumption was carried out. It was shown that average weighted error for determination of heat consumption by one apartment during the heating season does not exceed 6.5%. [ABSTRACT FROM AUTHOR]

Intellectual precise temperature sensor with wireless interface (ITWS) for contact measurements with absolute error of ± 0.05°C in the temperature range from 5 to 95°C was developed. Platinum thin film resistance thermometer was used as the sensitive unit. High accuracy of measurements is supported by following. Investigations and modeling of temperature dependence of resistivity for sensitive unit allowed to develop mathematical model ensuring calculation of temperature with the error not exceeding 5? 10-3°C. Original patented design, and hardware and software solutions for ITWS were developed. Method and mathematical models for thermocompensation of electronic components of ITWS were elaborated, which allowed sufficient decrease of measurement error during measurements and exploitation. Methodology, and hardware and software measuring system for individual ITWS calibration in automatic regime were developed, which include correction of mathematical model for the calculation of temperature for each sensor. ITWS has several design and technological solutions, and is developed for the temperature measurements of heat transfer agent in the pipelines of heating and hot water supply systems, independently of pipeline diameter. Measured data are transferred by radio channel to the recording and display devices. ITWS are used in automated systems for energy carrier controlling and determination of individual heat consumption. ITWS consists of following modules: sensitive unit, analog-to-digital converter, microcontroller, radio transceiver (carrier frequency is 434 or 868 MHz, output power of transmitter is not more than 10 mW), antenna and power supply (3.6 V). [ABSTRACT FROM AUTHOR]