Method of frequency control of an induction motor with a vector structure of flux linkages

An algorithm for controlling the torque or the rotation velocity of the rotor of an induction (asynchronous) motor with vector control of flux linkages is proposed. Stability of the control loops of the torque and rotor rotation velocity is analyzed, and results of simulating the operation of the proposed algorithms are described.     

Development and Implementation of the Casting of Rods Made of Refractory Cast Alloys

The problems of the production of a so-called casting rod blank made of a refractory casting alloy in the vacuum induction furnaces of AO Metallurgical Plant Electrostal are considered. A unique technology of casting and subsequent treatment of as-cast rod blanks made of refractory alloys is developed, tested, and optimized. As a result of the developed and performed measures for the production of metal products in the Consarc furnace, the ingot-to-product yield increases by 15% as compared to metal casting in an ISV-1.0 furnace. As a result, we have widened the range of cast alloy grades and are going to cast metals for the manufacture of blanks of other sizes and ranges of alloy an steel grades.     

A simple method of studying oxidation resistance of heparin-precipitated blood beta lipoproteins

Decrease of beta-lipoprotein resistance to copper-dependent oxidation is an important diagnostic criterion of risk of atherosclerosis. We developed a simple method for assessing resistance of heparin-precipitated beta-lipoproteins to oxidation induced by 50 microM copper ions. A strong positive correlation between the oxidation of precipitated and ultracentrifuged beta-lipoproteins in the presence of 50 and 10 microM copper ions, respectively, was revealed. In coronary patients oxidation resistance of precipitated beta-lipoproteins was decreased in comparison with that in healthy donors. The method is simple, informative, and easily available for clinical biochemical laboratories.     

Thermal conductivities of hex-1-ene,hept-1-ene,oct-1-ene,and dec-1-ene at 302–374 K

Measurements are reported on the temperature dependence of the thermal conductivity for olefins in the vapor state.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 55, No. 2, pp. 250–255, August, 1988.     

The diagnostic and treatment characteristics of diphtheria in troop units and military medical institutions

Medical records of 876 servicemen of a young age who have suffered various forms of clinical diphtheria were analysed. (Lethal cases were marked in 52 cases--5.9%). A true clinical symptom complex for the diagnosis of diphtheria at pre-hospital period is as following: fever, intoxication and febrinous tonsillitis. The main cause of unfavourable outcome of the disease depends on the affection of cardiovascular, central and peripheral nerve systems by diphtheritic exotoxin. The most frequent limitations during medical care were the following: error diagnosis of angina (41%), late hospitalization and late specific treatment, insufficient doses of antidiphtheric serum, inopportune diagnosis of severe aggravations (infectious toxic shock, pneumonia).     

Morphofunctional characteristics of alveolar macrophages under the effect of a toxic factor

The work was conducted on Wistar rats who had received orally the xenobiotic hexachlorocyclohexane (HClCH) in different doses. The sizes of the alveolar macrophages and type II pneumocytes as well as the parameters of macrophage phagocytosis were studies. Administration of HClCH in subtoxic doses not exceeding the pesticide residues in the food in the first two months stimulated synthesis of the surfactant and its phagocytosis by the alveolar macrophages; further administration of the primer led to exhaustion of the cell function. A toxic HClCH dose induced synchronous stimulation of the functional interaction of the alveolar macrophages and type II pneumocytes by the end of the second month. Synthesis of the surfactant and its phagocytosis were stabilized in the period of the after-effect of the drug.     

Stress echocardiography in localization of coronary atherosclerosis and assessment of it severity

193 patients with coronary heart disease were examined to study potentialities of noninvasive diagnosis of coronary artery lesions, their location and severity using transesophageal echocardiography in combination with transesophageal stimulation. This method of stress-test proved highly sensitive (89%) and specific (84%) in noninvasive diagnosis of both location of coronary atherosclerosis and its severity (stenosis, subtotal stenosis, occlusion) and extension.     

Secretory immunoglobulin A in the blood sera of healthy and ill persons

Sera of healthy and sick persons were tested for the presence of secretory IgA (SIgA) and free secretory component (SC) SIgA was present in the blood of healthy persons in low concentrations (1.07 mg/100 mg), and free SC was absent. Infectious and somatic diseases, in which damage of the epithelial covering of the gastrointestinal and respriatory tracts was possible, were accompanied by increased blood SIgA content. There was also noted a distinct relationship between the blood SIgA concentration and the severity of infectious diseases and pneumonia supervention. In these cases the SIgA level proved to rise.