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The calculation of the fluid flow in the interscapular channel of a centrifugal impeller with a finite number of blades, the construction of the energy characteristics of the impeller and its optimization by the number of vanes are considered. The calculation consists of two parts: firstly, the determination of the theoretical pump head taking into account the effect of a finite number of vanes based on the analysis of the force interaction, and, secondly, the determination of hydraulic losses in the impeller by integrating the friction stresses over the limiting surfaces. The results from both parts are used to optimize the number of vanes in the pump impeller.

Unregulated accumulation of phosphogypsum leads to dangerous geochemical flows with an avalanche effect. As a new option for the application of phosphogypsum, its dispersed placement in the small aggregate chernozem system at a depth of its modern anthropogenic illumination was described. A milling method for treating a soil layer of 30–60 cm was developed. Phosphogypsum and soil interact and agrophysical soil properties can be improved. The anthropogenic eluvial-illuvial structure of the soil profile can be eliminated. The morphological, agrophysical properties and soil moisture conditions, thermodynamic processes with Pb2 +, Cd2 + ions, the morphological parameters of the root system and the yield of sunflower after application of phosphogypsum during its utilization by dispersing in the soil layer of 30–60 cm were studied. Improved soil properties and conditions for development of the rhizosphere, passivation of heavy metals as a result of the carbonate-calcium equilibrium in the soil solution were described. The ecosphere and the agricultural production effect of phosphogypsum utilization in chernozem were substantiated.

The basic provisions of the mathematical model of a condenser-evaporator in relation to air separation units are considered. All influencing quantities are shown, the main component blocks are highlighted, and the sequence of their solution is given. The model is based on a joint solution of the equations of hydrodynamics and heat transfer for tubular apparatuses using iterative calculations to clarify the initial values of the determining parameters both within individual blocks and between blocks. Application of the model is possible for both design and verification calculations with minimal changes. The development of the considered model is associated with the adaptation of its algorithm to machine calculation. One of the main directions is the inclusion of a database of parameters of working substances in the field of vapor-liquid states with the ability to automatically search and transfer the required thermophysical parameters on the evaporation and condensation lines in the model.

The thermal calculation, which is part of the mathematical model of a condenser-evaporator of cryogenic air separation plants, is considered. The calculation is based on solving the criteria equations of heat exchange for cases of condensation outside of the pipe and evaporation inside the pipe. The thermal calculation is preceded by a hydraulic calculation, the results of which are used as input quantities. The solution is carried out by a multistep (iterative) method. The heat flow density on the evaporation side is used as a criterion for convergence of iterations. The calculation scheme, divided into successive steps, is shown. The calculation results are used to determine the geometric configuration and the main characteristics of the condenser-evaporator.

The long-term (30 year) dynamics of a solonetz soil complex composed of solonetzic light chestnut soils and chestnut solonetzes under standard conditions and with the application of agromeliorative measures are considered. When the standard zonal agricultural practice is used, the soils of the solonetzic complex have unfavorable agrophysical, chemical, and physicochemical properties and low productivity. After 30 years of the standard three-level tillage of the soils to a depth of 40–45 cm, the productivity of the biogeocenosis decreased. Thirty years after a single rotary-milling subsoil treatment of the 20- to 45-cm soil layer using a milling tool FS-1.3, there were no morphological features pointing to the restoration of the solonetzic process. The humus content in the 0-to 20-cm and 20-to 40-cm soil layers was 2.3 and 1.7%, respectively; the content of adsorbed Na+ in the 20-to 30-cm layer was 11.6% of the total exchange capacity, or 38% lower than its content in the reference soil. The additional yield reached 30–70% and more of that obtained with the standard agricultural technology used during the whole period under investigation. The method of systems biogeotechnology (systems bio-geo engineering) is proposed as a method for the preventive control of soil evolution and the maintenance of the stability and high productivity of the soil cover.

The hydraulic calculation, which is part of a mathematical model of a condenser-evaporator of a cryogenic air separation plant, based on the multi-step (iterative) method of equation of the hydrodynamic balance of a circuit with natural circulation.

Standard and ecologically corrected agricultural practices for a grain corn monoculture on ordinary, calcareous, moderately deep, moderately eroded chernozem with the use of the latest tilling implements are studied. The effect of primary tillage and herbicides Banvel and Milagro on the composition of the agrophytocenose and bioenergy efficiency of agricultural practice is established.

Changes in the properties of solonetzic soil associations (chestnut solonetzic soils and chestnut solonetzes) in the dry steppe after their reclamation have been studied for 30 years. The reclamation included the deep three-tier plowing and the approach of rotary tillage. A single rotary tillage operation resulted in the formation of fine aggregates of equal sizes in the plow layer; any morphological features of the restoration of solonetzic pedogenesis are absent. The atmospheric moisture easily penetrates into the soil, and soluble salts are leached off to a great depth. In 30 years since the soil amelioration with the use of a PMS-70 rotary tiller, the humus content has increased up to 3.3% in the upper 20-cm-thick layer and up to 2.4% in the layer of 20–40 cm. The content of adsorbed Na+ in the 20- to 30-cm-thick layer has decreased to 10.6% of the cation exchange capacity (in comparison with 19.8% in the nonreclaimed soil). The spatial heterogeneity of the soil cover has decreased in comparison with that prior to the reclamation. During the entire observation period, crop yields gained from the fields reclaimed with the use of the rotary tiller have been by 25–60% higher in comparison with those on the fields with traditional treatments.

An effective technology of growing crops with tilling solonetz by a PMS-70 rototiller was developed. On the basis of a long-term field experiment, a 30-year period of influence of cyclic soil ameliorative farming practices of chestnut-solonetz complex soils of the Rostov oblast is substantiated.

Experimental data on degradation of photovoltaic and photoenergetic characteristics of silicon solar cells exposed by high-energy electrons and protons as well as low-energy protons have been obtained. The previously proposed theoretical model that can describe degradation of the solar cell characteristics under the influence of irradiation, including that creating spatially inhomogeneous defect distribution over the structure thickness, has been experimentally confirmed. It was ascertained that in the cases of 1 MeV energy electron and 20 MeV energy proton irradiations, when there is a relatively homogeneous defect distribution over the silicon solar cell thickness, its shortcircuit current degrades faster than the open-circuit voltage. On the contrary, in the case of low-energy 0.1 MeV proton irradiation, when the distribution of defects is spatially inhomogeneous, the open-circuit voltage degrades faster than the short-circuit current.

The growth of the sick rate of limb peripheral vessels associated with a severe outcome (trophic ulcers, amputation) exerts an appreciable effect on the lowering of quality of life in patients. This manifests by the prolonged loss of work fitness, change of the habitual occupation and disability establishment. Objective analytical information on this problem will be of help in the delineation of the tendencies in this direction and potential approaches to the prevention of social losses. The present work is based on an analysis of 2115 statements of medicosocial expert evaluation (MSEE) of invalids suffering from diseases of limb vessels, performed over recent 8 years in the Altai region. The decisions made by the MSEE were based on the results of the clinical examination of patients using the current diagnostic modalities (ultrasonography, duplex scanning, angiography, etc). It has been established that among persons who had undergone MSEE, over the half (64.1%) were under 60 years, i.e. in the age of work fitness. It is noteworthy that the overwhelming number of invalids were men (83%) and workers (84.2%). As for special vascular pathologies, the majority of patients presented with obliterative arterial diseases (OAD) of the lower limbs, accounting for 76.3% whereas patients with venous pathology ranked second in number (15.9%). The highest severity of invalidism (groups I and II) was also recorded in OAD (77.5%), especially in atherosclerosis obliterans (AO) which accounted for 84%. Of note, these diseases were marked by no tendency toward reduction of their incidence. The time of temporary disability (from 3 to 9 months) was also most frequently recorded in OAD of the limbs. In OAD, the temporary or persistent loss of work fitness were caused by critical ischemia and amputations whereas in venous pathology, namely in varicosity and post-thrombophlebotic syndrome, the cause was progressing CVI complicated by trophic ulcers. On the whole, the lack of changes in the lowering of the number of invalids due to the given pathology evidences the unsatisfactory results of these patients' rehabilitation and the high socioeconomic tension determined by considerable treatment expenses and the high number of the disabled. Approaches to the escape from such a situation should be looked for in the early mass screening diagnosis of vascular lesions, early drug and surgical treatment and in the refinement of the system of rehabilitation prophylactic medical examination.

Modern definition, classifications, diagnosis and treatment of irritable bowel syndrome (IBS) are presented together with results of treatment of 30 patients with irritable bowel syndrome with the new selective calcium-channel blocker dicetel.

The chief factors of aggression are discussed together with mechanisms of protection of gastric and duodenal mucosa. Results of treatment of 30 patients with gastritis (Helicobacter pylori negative) with a cytoprotective drug smecta are presented.