Vertical Transfer of Momentum by Internal Waves in the Western Part of the Mediterranean Sea

Purpose. The work is aimed at studying both the momentum vertical transfer by internal waves with the regard for the Earth rotation and the shear current in the western part of the Mediterranean Sea, and the influence of turbulent viscosity and diffusion upon the indicated wave fluxes and the Stokes drift. Methods and Results. To solve the initial system of the hydrodynamics nonlinear equations, a weakly nonlinear approach was used. In the first order of smallness in the wave amplitude, the boundary problem for the vertical velocity amplitude was solved; in the second order in the wave amplitude, the nonlinear effects, namely the Stokes drift and the vertical wave momentum fluxes, were investigated. The indicated boundary problem was solved in two ways: by the perturbation method applied earlier and by the numerical one by the implicit Adams scheme of the third order of accuracy. The perturbation method assumes expansion of the solution and the wave frequency in a series by a small parameter proportional to the horizontal turbulent viscosity. The results obtained by the perturbation and numerical methods were compared. Coincidence of the results of calculating the dispersion curves by both methods is shown. However, for the wave damping decrement, the perturbation method yields the overestimated values, at that for the second mode the values are higher than those for the first one. The vertical wave momentum fluxes are nonzero, and theperturbation method yields the overestimated values for the flux uw. The vertical wave momentum flux vw is practically independent of turbulent viscosity and diffusion, and both methods give the identical results for it. The velocity component of the Stokes drift along the wave propagation direction is also insensitive to turbulent viscosity and diffusion, whereas the transverse component equals zero in the absence of turbulent viscosity and diffusion. Conclusions. The perturbation method provides the overestimated values of the wave damping decrements, the wave momentum flux uw and the transverse component of the Stokes drift velocity. The horizontal turbulent viscosity and diffusion exert practically no effect upon the wave momentum flux vw and the longitudinal component of the Stokes drift velocity

Hardening of leading edges of turbine blades by electrospark alloying

With a purpose of creating anti-erosion protection on turbine rotor blades the experiments in electrospark alloying using electrodes made of different materials: Т15К6 hard alloy and 15Х11МФШ steel were conducted. Reduction of the roughness of a surface layer having a uniform thickness was achieved upon its hardening with a steel electrode. The electrospark alloying process was perfected. Tests of mechanical properties of blade samples hardened with steel revealed overmatch of GOST requirements for strength and ductility. Increasing of surface layer microhardness was also achieved. For anti-erosion protection of leading edges of the turbine rotor blades it is recommended to replace the applied electrode made of Т15 К6 alloy with the one made of 15Х11МФШ steel.Для формування протиерозійного захисту робочих лопаток турбіни проведені експерименти з електроіскрового легування електродами з різних матеріалів: твердого сплаву Т15К6 і сталі 15Х11МФШ. Досягнуто зменшення шорсткості поверхневого шару, отриманого легуванням сталевим электродом, при однаковій товщині поверхневого шару. Відпрацьовано режим електроіскрового легування. Випробування механічних властивостей зразків лопаток, зміцнених сталлю, показали перевищення вимог ДСТУ з характеристик міцності та пластичності. Досягнуто також підвищення мікротвердості поверхневого шару. Рекомендована заміна електрода із сплаву Т15К6, що використовується, на електрод із сталі 15Х11МФШ, для захисту від ерозії вхідних кромок робочих лопаток турбін.Для формирования противно эрозионной защиты рабочих лопаток турбины проведены эксперименты по электроискровому легированию электродами из различных материалов: твердого сплава Т15К6 и стали 15Х11МФШ. Достигнуто уменьшение шероховатости поверхностного слоя при одинаковой его толщине после упрочнения стальным электродом. Отработан режим электроискрового легирования. Испытания механических свойств образцов лопаток, упрочненных сталью, показали превышение требований ГОСТ по прочности и пластичности. Достигнуто также повышение микротвердости поверхностного слоя. Рекомендована замена применяемого электрода из сплава Т15 К6 на электрод из стали 15Х11МФШ для защиты от эрозии входных кромок рабочих лопаток турбин

Prediction of the number of HBSAg carriers in pregnant women

Отримана можливість прогнозування кількості носіїв HBSAg серед вагітних на наступний рік. Для того, щоб похибка була невеликою, підібрана математична залежність між часом у роках і числом вагітних-носіїв HBSAg у м. Чернівці на основі даних щорічного обстеження вагітних за період з 1990 до 1996 року. Згідно з прогнозуванням, у 1997 році можлива кількість вагітних-носіїв HBSAg була у Чернівцях 223, а фактично їх було виявлено при обстеженні 213, тобто відносна похибка прогнозу складає 4,7%. Прогнозування числа носіїв HBSAg серед вагітних дає можливість розраховувати кількість необхідної вакцини для щеплення новонароджених жінками-носіями HBSAg, а також вчасно розробити протиепідемічні заходи.There were 40306 pregnant women who were examined in Chernivtsi, Ukraine over a period from 1990 to 1996. A mathematical model based on our data during 7 years is presented in this article and was the best one to show the approximate level of HBSAg carriers among pregnant women in the next year. A mathematical model is needed for the purpose of determining the amount of vaccine for prophylaxis of newborns and for identifying the future epidemic situation in this part of Ukraine

Ultrasonic color Doppler imaging to assess the efficacy of orbital decompression in Graves’ ophthalmopathy

A.A.&nbsp;Kalandari, A.G.&nbsp;Nosova, N.Yu. Kutrovskaya, O.V.&nbsp;Levchenko Moscow State University of Medicine and Dentistry named after A.I.&nbsp;Evdokimov, Moscow, Russian Federation Orbital soft tissue ultrasound is particularly important for specialists providing care for Graves’ ophthalmopathy (GO). In addition to echo signs of non-inflammatory edema and/or proliferation of retrobulabar fat, extraocular muscle thickness, their density, and contractility, changes in orbital blood flow should be considered as well. Multiple previous studies demonstrate reduced blood flow in the superior ophthalmic vein. However, recent studies poorly address this issue, therefore, these publications are vital to investigate the problem. Ultrasonic color Doppler imaging evaluates hemodynamic changes in the orbital blood flow in GO. Changes in linear blood flow velocity in the superior ophthalmic vein are an additional diagnostic criterion for the severity of autoimmune disorder in these patients. Abnormalities of venous blood flow promote non-inflammatory edema of retrobulbar fat, proptosis, and orbital compression. However, linear blood flow velocity in the oph thalmic artery, central retinal artery, and posterior ciliary arteries as well as arterial resistive index should be also considered to predict disease course and to sel ect treatment strategy. Evaluation of hemodynamic changes and their severity can specify the terms and surgical strategy for GO. Being safe and non-invasive tool, ultrasonic colour Doppler imaging can be applied postoperatively. Improved superior ophthalmic vein blood flow fr om orbital soft tissues and reduced resistive index of ophthalmic artery are potential criteria for GO surgery efficacy. Keywords: Graves’ ophthalmopathy, hemodynamic changes in orbital vessels, superior ophthalmic vein, ophthalmic artery, color-flow duplex scanning, orbital decompression. For citation: Kalandari A.A., Nosova A.G., Kutrovskaya N.Yu., Levchenko O.V. Ultrasonic color Doppler imaging to assess the efficacy of orbital decompression in Graves’ ophthalmopathy. Russian Journal of Clinical Ophthalmology. 2019;19(3):150–153. <br

Influence of hydrothermal conditions on the phase transformations of amorphous alumina

Amorphous Al2O3 transforms into the pseudoboehmite and boehmite phases of AlO(OH) under hydrothermal conditions. Specific surface area, pore volume and the amount of acidic sites decrease upon complete conversion of amorphous Al2O3 into boehmite

Conceptual approaches to overcoming turbulence in the innovative development of Russian industrial enterprises

The article attempts to give scientific justification to rational construction of the National strategy of overcoming turbulence in the innovative development of Russian industrial enterprises that is expected to help identify new competitive advantages and improve those connected with the growth of scientific and technological potential, of both the state and business. It is argued that in the current socio-economic conditions, the most promising direction is the development of cutting-edge technologies. The role of knowledge, innovation market, and other points of high-tech growth are determined. The necessity of the development of innovative territorial clusters based on the interaction between representatives of science, business and the government is substantiated. The choice of priority directions of innovation development is made keeping in mind international institutional, scientific, technical and technological forecasts and trends and is aimed at successful identification of the determinants of high-tech growth and formation of competitive advantages of the Russian economy that will allow to overcome the turbulence in the innovative development of the Russian economy. © Serials Publications Pvt. Ltd

Pb, Cd, Se, As in blood and urine of children from high and low polluted districts of Saint-Petersburg. The elements concentrations and health of children

At present time rapt attention is attended on child health. One of the main factors of child health is environmental condition and possibility of toxic elements consuniption by children from air, water, and food. The ain of our investigation is to detennine Pb, Cd, Se, As in blood and urine of children from high and low level polluted districts of St.-Petersburg. And then to estimate urine and blood toxic elements concentration correlation. ln order to examine large child groups it is necessary to use effective, express analycal methods. Wc chose Zeeman Modulation Polarization Atomic Absorption Spectrometry with High-Frequency Modulation as such a method. New technique Zeeman Modulation Polarization Atomic Absorption Spectrometry with High-Frequency Modulation allow io determine many etements directly (without additional compounds and reagents or with there minimum use) in blood, plasma and urine. Highcst spectrometry selectivity allows working with high background level. The matrix effects are reduced in great deal the aid of L'vov platform, sample pyrolysis and palladium modifier using. We present the results of our investigation – the concentration of toxic éléments in blood and urine of children from high–Polluted district is above permitted level

Conceptual approaches to overcoming turbulence in the innovative development of Russian industrial enterprises

The article attempts to give scientific justification to rational construction of the National strategy of overcoming turbulence in the innovative development of Russian industrial enterprises that is expected to help identify new competitive advantages and improve those connected with the growth of scientific and technological potential, of both the state and business. It is argued that in the current socio-economic conditions, the most promising direction is the development of cutting-edge technologies. The role of knowledge, innovation market, and other points of high-tech growth are determined. The necessity of the development of innovative territorial clusters based on the interaction between representatives of science, business and the government is substantiated. The choice of priority directions of innovation development is made keeping in mind international institutional, scientific, technical and technological forecasts and trends and is aimed at successful identification of the determinants of high-tech growth and formation of competitive advantages of the Russian economy that will allow to overcome the turbulence in the innovative development of the Russian economy. © Serials Publications Pvt. Ltd