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31.
A new method for an experimental study of burning processes in condensed substances is suggested, based on the statement and solution of inverse problems. An inverse problem of reconstructing the erosive burning rate of solid propellants from experimental data is formulated. The choice of an approach to solving the problem by the joint application of well-known methods for inverse problem solution and specific features of experimental studies of burning processes, in particular, erosive burning, has been justified. The problem solution is illustrated by a numerical example. The testing involves a comparative analysis of two optimization methods: although both methods are characterized by an identical accuracy, the steepest descent method has a higher rate of convergence for this class of problems than the conjugate gradient method.  相似文献   
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Conclusions -- The effect of the component air streams on yarn uniformity with respect to linear density has been established. This has afforded opportunity to find an optimum regime for yarn cooling in spinning from polymer melts. Analysis of the pulsations in air streams has made it possible to determine the basic sources for their origin and ways to reduce them.-- A manufacturing control of the yarn cooling regime using anemometers has been proposed.-- A way of intensifying the yarn cooling regime using an air jet on the yarn section after its initial hardening has been described.-- It is recommended to use the method of investigating the process of yarn spinning by analysis of the component air streams in preparing fibres from polymer melts on any type of spinning equipment.Translated from Khimicheskie Volokna, No. 4, pp. 26–30, July–August, 1990.  相似文献   
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The interaction of thirteen antiarrhythmic active phenothiazine 10-acylaminopropionil derivatives with artificial phospholipid membranes was studied. Blinding constant (K) of this interaction was determined by means of a fluorescent probe. There was found a valid correlation between K and antiarrhythmic activity (A) for 10 substances; the greater the K--the greater the A. Three substances characterized by the greatest K had, however, a low A. It can be assumed that the interaction of antiarrhythmic drugs with phospholipids of target membranes in vivo is an important element of the molecular mechanism of action. At the same time a very high affinity to lipids can possibly cause a delocalization of the drug in the organism and a decrease of its antiarrhythmic activity.  相似文献   
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At the final stage of long-term space flights first aid should be rendered in a specific way in cases of critical situations. Resuscitation and anesthesiology measures should be applied, if necessary, after study of flight-induced changes in the vital organs and systems. The paper describes the most important factors that should determine the tactics of resuscitation-anesthesiology support of the immediate postflight stage, if theoretically feasible acute life-endangering states develop. It also presents substantiated correction of routine clinical protocols of resuscitation aid.  相似文献   
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The macrophage adherence inhibition was studied in the peritoneal macrophages of guinea pigs with induced posttraumatic aspermatogenesis at various periods after the testis injury. Reliable peritoneal macrophages adherence inhibition was observed in the presence of the testis-specific antigen. The adherence inhibition reflected the autoimmune character of the testis affection.  相似文献   
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Hygienic processing of the underwear in a device combining mechanical treatment, forced pumping of the washing solution and wringing by compressed air can be used under special conditions. The basic parameters of the engineering process have been determined, viz.: the number of washing baths, temperature of the water, time of processing, etc.  相似文献   
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