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One of the most important parameters of powerful hydro generators (HG) is the air gap between the rotor and the stator, and its deviation from the set norms is a defect that can lead to serious accidents. Therefore, the size and shape of the gap must be monitored both during inspections and during operation of the machine. The aim of this paper was to develop a secondary measuring transducer providing accuracy and resolution for a capacitive gap sensor formed by coplanar parallel electrodes. It is shown that the reliability and safety of operation of powerful HG inextricably depend on the timely detection of their defects, especially during operation. One of the most important parameters of the HG is the air gap between the rotor and the stator, and its deviation from the set norms is a defect that can lead to serious accidents. Therefore, the size and shape of the gap must be monitored both: during inspections and during operation of the machine. The paper discusses the features of measuring the air gap in a powerful HG, as well as existing modern methods and means of measurement. It is shown that for measuring the gap in capsule HG, one of the most suitable means is a meter, which includes a capacitive sensor mounted on a central bore of the stator core. Commercially available gap meters with capacitive sensors are not suitable for use on HGs. Commercially available meters with capacitive sensors, by their certain characteristics, are not always suitable for use on HGs. A secondary measuring transducer with improved characteristics is proposed for a capacitive gap sensor formed by coplanar parallel electrodes. The converter is developed on the basis of a balanced compensation bridge measuring circuit. The control action in the device is formed by the phase of the unbalancing signal. The structural diagram of the converter is presented and the algorithm of its operation is described. The process of forming a measuring output signal proportional to the sensor working capacitance in the circuit is considered. The use of a capacitive sensor with coplanar parallel electrodes and the proposed secondary measuring transducer will ensure high accuracy and resolution when measuring the air gap.

This paper introduces the specific application of adjustable reactor, expounds its development history and research trend, and classifies the existing adjustable reactors according to their regulation modes. For various types of adjustable reactors, the working principle is introduced in detail, the structure diagram is given, and some application examples are introduced. Some special types of adjustable reactor are also introduced, such as virtual air gap adjustable reactor, magnetic circuit transfer type adjustable reactor, etc. Then, the performances of various adjustable reactors are compared and analyzed, and their advantages and disadvantages are summarized, and their application prospects are preliminarily evaluated.

The paper describes the possibility of application of the vortex effect in a mobile thermostatic unit. The structural diagram of the unit and the results of tests are presented. It is shown that the technological efficiency of the Ranque–Hilsch vortex tube used in the unit can be increased by forced cooling of the tube housing or solely its hot flow outlet.

A method for determining the location of damage to the insulation of power lines cables or communication line cables is proposed. The wires of a damaged cable communication line or power electric cable of various classes of AC and DC voltage as elements of a multipolar electric circuit of the “star” type are considered. A structural diagram of the developed device is presented, and a theoretical evidence of the developed method for measuring the distance to the place of damage to the insulation of communication cable or power transmission cables is given. Equations for calculating the distance to the place of cable insulation damage are obtained. The results of an experimental verification of the developed method and device for measuring the distance to the place of damage to the cable insulation are presented.

Improving open-circuit voltage is critical to improving the performance of diamond nuclear battery. ZnO films have been successfully used as the electron transport layer of diamond Schottky nuclear battery in this work. The open-circuit voltage of device with ZnO layer is increased from 1.03 to 1.43 V and the conversion efficiency is increased by 100% to 1.42% compared with device without ZnO layer. By comparing the device structure diagram and potential distribution before and after adding the ZnO layer, we try to find out the cause of the increase in open-circuit voltage. This research provides a new way to improve the open-circuit voltage and conversion efficiency of nuclear batteries.

We analyze the structure diagram for binary clusters of Lennard-Jones particles by means of a global optimization approach for a large range of cluster sizes, compositions and interaction energies and present a publicly accessible database of 180,000 minimal energy structures (http://softmattertheory.lu/clusters.html). We identify a variety of structures such as core-shell clusters, Janus clusters and clusters in which the minority species is located at the vertices of icosahedra. Such clusters can be synthesized from nanoparticles in agglomeration experiments and used as building blocks in colloidal molecules or crystals. We discuss the factors that determine the formation of clusters with specific structures., Comment: 6 pages, 6 figures

A novel method and equipment for measuring concentration of polyhexamethylene guanidine in multicomponent medical disinfectants on the basis of UV spectrometry is described. Basic characteristics and the structural diagram of the automated spectrophotometer are described, and the software is described. The results of the trials of the system in comparison with the results of the conventional photometric method based on the reaction with eosin are given.

The effects of Mn substitutions on the crystal structure, magnetic properties, and magnetocaloric effect (MCE) of antiperovskite Sn 1− x CMn 3+ x (0≤ x ≤0.40) have been investigated detailedly. Both the Curie temperature ( T C ) and the magnetizations at 40 kOe decrease with increasing x firstly for x ≤0.10, and then increase with increasing x further. The type of magnetic transition changes from first-order to second-order around x =0.10 with increasing x . Chemical composition-dependent MCE is also studied around T C . With increasing x , the maximal magnetic entropy changes decrease and the magnetic phase transitions broaden. Accordingly, the relative cooling power (RCP) increases with increasing x , reaching the largest values of ∼0.56 J/cm 3 (∼75 J/kg) and ∼1.66 J/cm 3 (∼221 J/kg) with the magnetic changes of 20 kOe and 48 kOe, respectively. Considering the large RCP, inexpensive, and innoxious raw materials, these serial samples Sn 1− x CMn 3+ x are suggested to be potential room-temperature magnetic refrigerant materials.

The problems arising during nondestructive quality tests of articles of nonmagnetic alloys and during sorting in the electrical conductivity are considered. The function and performance characteristics of a ВЭ-26НП eddy-current structruroscope are described. The structural diagram of this device and the algorithm of its operation are described. The capabilities of the ВЭ-26НП eddy-current structruroscope for performing nondestructive quality tests of thermal treatment of articles made of nonmagnetic materials are analyzed.

It is proposed to supplement a phase diagram by a structural diagram, which represents the mass portions of phases, conglomerates or their elements upon the system concentration at fixed temperature. Methods of structural diagrams and concentration maps construction are considered. Concentration map is a projection of structural diagram. It marks a concentration triangle by the lines of constant mass portions of a phase or its elements.

Experiments were carried out to synthesize boride phases in the Al-B and Al-B-C systems. In the Al-B-C system, as well as the AlB2 and α-AlB12 phases the borides C4AlB24 and C2AlB48 were formed and these are isomorphous to the phases AlB10 and β-AlB12 respectively. In the Al-B system no phases with the structures AlB10 and β-AlB12 were detected. A modified structural diagram of the Al-B system is proposed.

The structural diagram of the TlSeDySe system has been constructed by the methods of differential thermal analysis and the results of microhardness measurements. At room temperature the solubility of DySe is TlSe is established to be 4 mol%. As a consequence of the investigations, TlDySe 2 compound (paramagnetic) is disclosed at peritectic reaction.

Phase methods of conversion provide a means of increasing the measurement rate for nonelectrical quantities.

1. A structural diagram was constructed for 25% Cr steel that allows one to determine the minimum concentrations of nickel and nitrogen guaranteeing a stable austenitic structure. 2. Alloying the steels with nitrogen is accompanied by a linear increase of the strength characteristics in short-term and long-term tests at room and elevated temperatures. The nitrogen-containing steels have the best combination of properties when microalloyed with boron. 3. Increasing the nickel concentration in nitrogen-containing steels to the upper limit required to obtain a \gg solid solution has no effect on the mechanical or heat-resisting characteristics.

The attenuation of plastic concrete creep is analyzed on the basis of the structural diagram, and a formula relating total strain and compressive stress is derived. This formula is in good agreement with the experimental data, as demonstrated by fitting the experimental creep curves.

The problems which confront anyone who wishes to study the factors that control the formation and structure of phases or compounds—what combinations of what elements will form stable phases under what conditions and with what crystal structures—can best be expressed by quoting from the proceedings of a conference on phase stability in metals and alloys held in 1966.(1) The remarks, somewhat rearranged in order, are by W. M. Lomer.*

A system is considered for automating research on the behavior of materials under different forms of unilateral heating; a structural diagram is given.