Differential calorimeter for studying composites

The novel design of the DK-600/K differential thermal-flux calorimeter, with a cell volume of 6.5 cm³, is intended for the study of materials in the temperature range 300–900 K. The sensitivity of the calorimeter is 22 μV/mW at 300 K and 8 μV/mW at 900 K; the reaction threshold is 80 μW in the temperature scanning mode and 7 μW in the isothermal mode. Comparison of some characteristics of the DK-600/K with analogs from a number of foreign firms shows that it is competitive. Translated from Izmeritel'naya Tekhnika, No. 3, pp. 41–43, March, 1994.     

Integrated information resource system of the Russian Academy of Sciences and a technology for developing digital libraries

Problems of developing digital libraries are considered. An analysis of this class of distributed information systems is given. The main effort is focused on the formalization of properties of the stored objects and operations, which makes it possible to construct a formal model of digital libraries. This model can serve as a basis for designing development tools. Systems based on this approach are called integrated information resource systems (IIRS). In particular, the information retrieval system of the Russian Academy of Sciences (IIRS RAS) is based on these principles. The paper is organized as follows. First, the aim of the paper is outlined. Then, the definition of a digital library is given (as it is understood by the authors), basic concepts are discussed, and IIRS is considered as a digital library. The notion of the resource is introduced as the basic object to be processed. Metadata and their role in the system of digital libraries are considered, as well as the role of relationships and data organization. Then, the architecture and functional capabilities of IIRS are considered, and, in particular, a metamodel of the system, data search, and the implementation of data distribution. The current implementation of IIRS RAS is briefly outlined.     

Experience gained with development of the instrumentation and control system for the PGU-410 power unit at the Krasnodar cogeneration station on the basis of the tornado-n distributed control system

The development of the instrumentation and control system for the PGU-410 power unit at the Krasnodar cogeneration station is discussed. Problems encountered in designing the process control system of a complex facility are considered, in particular, the need to integrate local control systems. Special attention is paid to the importance of setting up a united control area at such facilities.     

Experimental investigations and mathematical simulation of the operation of ionizing-radiation diamond detectors

A mathematical model of an ionizing-radiation monitor based on diamond detectors has been developed. Experimental investigations of the monitor were carried out, and, using their results, the model was verified and optimized. It was demonstrated that the developed model makes it possible to calculate data of sensor measurements with an accuracy of 10% or better. These results will be used to reconstruct cosmicradiation spectra according to the output data of the monitor.     

Modern computerized automation systems for thermal power engineering and prospects for their future development

The possibility of using the Ethernet network as a network for the lower (controller) level of a computerized automation system is considered. A new term “distributed (multicore) control environment” is introduced. The architecture of an Ethernet-based distributed control environment is described and an example of its implementation in the Tornado-N computerized automation system is given.     

Thermogravimetry in the analysis of results of a calorimetric experiment

A method based on a refined measurement equation is proposed for enhancing the accuracy of measurements of the specific heat of solids. The equation uses calorimetric and gravimetric output signals along with analytical representation of the output and baseline signals. Translated from Izmeritel'naya Tekhnika, No. 9, pp. 26–28, September, 1998.     

Radiation experiments with hydrogen-containing materials on the URAM-2 cryogenic irradiation facility at the IBR-2 reactor

The URAM-2 irradiation system facility at the IBR-2 reactor is described. The results of experiments performed with this facility to study the behavior of water ice, solid methane, aromatic hydrocarbons, and other materials exposed to fast neutrons and rays are presented. The rate of energy accumulation in these materials under irradiation and the amount of accumulated hydrogen and the temperature at which the hydrogen leaves the material matrices are determined. Recommendations are made for the working temperature of these materials for use in cold neutron moderators.Translated from Atomnaya Énergiya, Vol. 97, No. 3, pp. 183–189, September, 2004.     

Laser-induced breakdown method for code detection (identification) in explosion products of coded explosives

The results of a study on the development of a method for coding explosives are presented. As coding additives (CAs), it is proposed to use aluminum alloy powders with dosed amounts of rare-earth coding elements (CEs). This choice is dictated by the fact that aluminum alloys are commonly used as efficient additives in explosive compositions, while rare-earth elements are used as additives in technological operations, but are absent in the composition of standard explosives. In this case, the key to information on a given explosive and its manufacturer is the ratio of CE concentrations determined when analyzing explosives, e.g., when investigating an act of terrorism. Examples of explosion product decoding using a LIES laser-spark express analyzer.     

Reasons for the formation and growth of edge cracks on hot-rolled plates of steel 10KhSNDA

A thorough study of the technology used to obtain hot-rolled plates of steel 10KhSNDA at Ural Steel determined the mechanism responsible for the formation and growth of edge cracks in the plates. The implementation of suitable technical measures has reduced the incidence of plate rejection for this defect to almost zero.     

Self-modulated generation observed in a delayed feedback relativistic microwave gyrotron

Self-modulated generation regimes were studied in a delayed feedback relativistic gyrotron operating on the H ₀₁ mode with a central frequency of 9.2 GHz. At a fixed electron beam energy of 230 keV, an increase in the electron beam current from 10 to 45 A led to the transition from a stationary to periodic self-modulated generation regime. The modulation period was about 16 ns, while the relative amplitude of the modulation increased in proportion to the beam current, reaching up to 90%. The microwave pulse duration exceeded 6 μs at an average power of up to 1 MW. The experimental data obtained agree well with the results of simulation using the PIC code KARAT.