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Complex investigations of high-temperature thermoelectric material nanostructured Si0.8Ge0.2P0.022 ntype were carried out. Temperature dependencies of conductivity, thermoelectric coefficient and thermal conductivity were studied. Obtained data were used for the calculation of temperature dependence of ZT. Maximum value of ZT  1.04 is observed at 900 °C. Differential scanning calorimetry indicates on the high thermal stability of the nanostructured material. It was established that optimal temperature range for the application of the material in the multisectional legs of thermoelements is 600-900 °C. [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]

One of the main issues of the device technology on metal-dielectric (MD) substrates is poor adhesion of thin metallic films, which are used for interconnections in electrical circuits. Films are formed by vacuum deposition on a porous dielectric layer of substrates. The presence of pores sufficiently complicates the cleaning of the substrate surface, which significantly decreases the adhesion of the film deposited on it. Technology of metal films with high adhesion, fabricated by ion-plasma method is proposed in this work. Films were deposited on MD substrates produced by electrochemical oxidation of aluminum alloys. The main operations of the technology are the following. Removal of residual electrolyte after the oxidation is carried out by rinsing of substrates initially under running hot water, and then in deionized water, followed by drying in a flow of heated nitrogen. Annealing of substrates under the pressure of 10-3 Pa and temperature of 550-570 K for 20 min is carried on in the vacuum chamber before the deposition of metal films. Copper is used as the main material of the interconnection films. Adhesion sublayer is fabricated on the basis of chromium or vanadium, which have high enthalpy of the oxide formation. Measurements showed that the copper films with the thickness of 1.5 µm, deposited on the vanadium sublayer with the thickness of 0.12 µm, which is comparable with the roughness of oxide layer, have adhesion of 25 N/mm² at the temperature of 520 K. Investigation of adhesion was carried on by the method of direct tear off with the error of up to 10%. [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]

The heat capacity of the n-Bi2Te2.88Se0.12 and p-Bi0.52Sb1.48Te3 solid solutions has been measured from 360 to 600 K. The data, represented in the form C p = a + bT + cT −2, have been used to evaluate the thermodynamic functions of the solid solutions in the range 298.15 to 600 K. [ABSTRACT FROM AUTHOR]