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In this paper, the authors present the deformation equation in the form of a system of nonlinear non-stationary differential equations. They are presented in partial products describing the deformations occurring in the river. This paper presents a mathematical model and an algorithm for calculating channel deformations in the inflowless section of channel processes. The system of non-stationary differential equations has been provided in the work. The presentation concerns the construction of hydroelectric power plants on the Amu-Darya river.

The protective black-saksaul pasture strips in the southern Central Asian deserts apparently increase the relative humidity, change the air and soil temperature regimes, reduce the wind speed, and prevent the melting of snow and the drying out of soils. Therefore, there are more favorable hydrothermal conditions for the growth and development of native wormwood ephemeral plant within the strip and the adjacent pastures lands. The plant species composition in the black-saksaul strip becomes more diverse; the ephemeral grass density is higher than that on the open pastures. The productive function of the black-saksaul strips includes two components: the production of black saksaul–fodder mass and the production of natural wormwood ephemeral pastures in the zone of the effects of positive environmental modification by the black-saksalul strips. Rational use of the black-saksaul pasture strips should involve pasture grazing twice a year: in spring, the sheep should graze on ephemera; the second grazing season on black saksaul (assimilated shoots and seeds) is in the autumn–winter period.

The results of experimental studies of emulsification processes in rotor-disk mixers having various designs of the working units that allow control of size-wise disperse particle distribution are reported. It is shown that the size of disperse particles decreases with increase of the area of perforations in the working units of rotor-disk mixers and with installation of additional components (teeth). Thereupon, the power consumption increases because, with the experimental parameters (rotation frequency, flow rate, ratio of mixer components, etc.) remaining identical, the average size of disperse particles decreases and, consequently, the interface area increases.

At coming up with of civil engineering constructions within the watercourse hydraulic calculation of the riverbeds is made. Hydraulic calculation establishes bottom main parameters: width, depth of a stream and radius of curvature of the river beds, and so on. In article results of studying of changes of morphological parameters of the riverbed are yielded: width of a bed, average depths of a stream and radius of a dynamic axis of a stream on river beds in conditions of regulated a water flow on water basins. On the footing of the statement of results from examination of hydraulic parameters of a stream with use of a method of dimension connections of width, average depths of a stream and radius of a dynamic axis of a stream from the factor forming a river bed are received.

The paper describes the synthesis of germanium nanotubes in an argon microarc. The article presents the results of two experiments. The evaporation of germanium atoms was carried out from the surface of single-crystal germanium, which served as the anode of the microarc discharge. The synthesis of nanotubes was observed on the surface of a molybdenum cathode in the first experiment and on the surface of a graphite rod in the second experiment. The diameters of the obtained germanium nanotubes reach 800-900nm.

In this paper, the synthesis of semiconductor spherical nanostructures is carried out by the plasma-chemical method. The sizes of the obtained nanospheres range from 100 nm to 1 mm. These structures are open on one side, have thin walls with a thickness of several nanometers, which end with “tentacles” with a diameter of several nanometers. Since the synthesis involved three elements of the fourth group of the periodic table (germanium, silicon, carbon), it has not yet been possible to determine the crystal structure of the obtained samples. All three elements are present on the surface of the sample in atomic percentages Ge-2.5%, Si-8%, C-55%. In addition to these elements, oxygen is also present in the spectrum.

This paper presents the results of the synthesis of nanodiamonds and carbon nanotubes in silicon-argon plasma. At a pressure of 500 Torr in the plasma reactor, carbon atoms evaporated from the surface of the graphite anode of the electric arc. The peculiarity of the graphite anode was that small pieces of silicon were embedded on the surface of the anode. As a result of the experiment, nanodiamonds and carbon nanotubes were formed on the surface of the graphite cathode. The linear dimensions of nanodiamonds range from 10 to 50 nm. The diameters of carbon nanotubes range from 4 nm to 20 nm, and their length is from 100 to 2 microns.

There is given a method of aerodynamic resistance coefficient determination of small-sized devices sprinklers of recycled water-cooling (mini cooling towers) in this article. Mini cooling towers are widely used at systems of recycled water supply in enterprises, because it are mobile, services a specific technological units or apparatuses, have a less energy intensity, more effective and safety unlike of oversized. There was compared two types of mini cooling towers in this labor: small-sized cooling tower with twisted air flow and with counter current flow. Also was developed and made the experimental unit for carry out of aerodynamic tests. The experiments on determination of aerodynamic resistance coefficient carried out depending on air flow rate in the interval from 0.5 to 3 m/s and irrigation density from 0 to 12 m3/(m2h). It shown that the sprinkler OB-65 (for mini cooling towers with twisted air flow, with diameter mesh casings 65mm) have more high aerodynamic resistance coefficient than the sprinkler OGGT-65 (for mini cooling towers with counter current flow with diameter mesh casings 65 mm) at the equal parameters of the experiment. Obtained coefficients of aerodynamic resistance of sprinklers in the mini cooling towers with the twisted air flow and with counter current flow approximated by the method of least squares and are presented as linear dependences in logarithmic coordinates of aerodynamic resistance and Reynolds number. It known that the coefficient of aerodynamic resistance is determine by common relation A/ReK.

The classification of membranes and membrane methods of water treatment on various grounds, the analysis of membrane separation methods and their application for wastewater treatment chemicals and oil refineries, containing biologically recalcitrant pollutants (oil, phenol and derivatives). It was shown that wastewater treatment chemical and petrochemical enterprises are most preferred hybrid technology based on the use of catalytic membrane reactors ultrafiltration ceramic or metal-ceramic membranes in the presence of ozone. Advances in membrane technology related to the development of membranes and membrane-purpose vehicles of new generation allow us to solve the actual problem – the creation of local systems, mobile and stationary applications that combine traditional and baromembrane liquid separation processes.

A highly efficient construction of the sprinkler of cooling towers manufactured from polymer materials is presented. Mathematical relationships and a technique of calculating the basic technological characteristics of the sprinklers of cooling towers are obtained.

Data, that were received during measurement of gap between vessel’s shell and restorative ring of vessel’s connecting pipe is represented. Misfit between real connecting pipe’s geometrical characteristics and objectives of quality standards, for instance GOST R 52630. Simulation of deflected mode is done to validate the currency of increasing connecting pipe’s workmanship. The influence of gap’s dimension between vessel’s shell and restorative ring on deflected mode was analyzed. The simulation was done with using of finite-element method in program ANSYS. Next data and results of simulation are shown and analyzed in the article: curve of stresses along the vesel’s generating line as a function of distance to vessel’s connecting pipe, curve of maximum stresses in vessel’s connecting pipe as a function of gap’s dimension between vessel’s shell and restorative ring and stresses field on vessel’s connecting pipe surface. Analysis of curves showed irregularity of stresses field on vessel’s connecting pipe surface and that the maximum level of stresses is on the inner surface of connecting pipe in the area of vessel and pipe joint. This fact is not influenced by the presence of restorative ring. Imperfection of vessel’s shell connecting pipe design procedure is shown. The main reason of design procedure’s imperfection by author’s opinion is non-considering of gap between vessel’s shell and restorative ring of vessel’s connecting pipe.

The article deals with the features of composition in architectural design for most of cases. On the basis of well known parameters of form there is conducted a comparison with different kinds of visual Arts. There is established that at present time ordinary averaged architecture has definite natural restrictions in form and placement. A value and colour are the elements which have more possibilities for the real architectural practice. They are relatively cheap in comparison to form and placement.

The boundary-domain integral method with the analytical integrals over the individual boundaries and internal cells for the solving the boundary value problems of fluid flow problems is developed. The axisymmetric potential flow of an incompressible fluid around a sphere, the fluid flow in a porous medium with spatially inhomogeneous permeability and the problem of convective-diffusive transport of a gas suspension in a periodic cell are calculated The comparison of the numerical results with analytical solutions show the efficiency and good accuracy of the developed boundary-domain integral method.

An experimental installation designed for engineering tests of sprinkling and water trapping devices is described. Aerodynamic tests were performed to determine the aerodynamic resistance coefficient of sprinklers and water traps and its dependence on the recirculating water and air flow rate. Hydroaerothermal tests were performed to determine the relative circulating water temperature based on a host of physical parameters. The experimental installation developed permitted measurements of the key process parameters with fair accuracy.

We prove one strengthening of the Darmois--Skitovich--Ramachandran theorem on characterization of normal distribution by independence property of linear statistics.

We consider the problems of designing integrated mathematical models for stratum fluids filtration and gas-liquid mixture flows (i.e., oil, natural gas, and water) in oil- and gas-gathering pipelines. The modeling process lies in finding a generalized solution to an initial boundary problem for a system of equations describing real physical processes in oil and gas strata, shafts, and ground-based gathering pipelines. We suggest and study methods to solve the systems of nonlinear algebraic equations defined by the space-time approximation of the initial boundary problems belonging to the class considered.

A review of the career of Anatolii Vladimirovich Skorokhod, who passed away on January 4, 2011. He was an outstanding scientist, the author of fundamental works in the theory of probability and statistics, and academician of the National Ukrainian Academy of Sciences.

Inequalities for the moments of the maximum of the sums of elements of a random stationary sequence are suggested. The consequences of the results obtained include the Polya-Vinogradov inequality for sums of the Dirichlet characters.

Let $(X,Y)$ be a random vector whose first component takes on values in a measurable space $({\mathfrak{X}},{\mathfrak{A}},\mu )$ with measure $\mu$, and let Y be a real-valued random variable. Let $$ f(x)={\bf E}\{Y\mid X=x\} $$ be the regression function of Y on X. We consider the problem of estimating $f(x)$ by observations of n independent copies of $(X,Y)$ given $f\in{\bf F}$, where ${\bf F}$ is an a priori known set with specified metric characteristics such as $\varepsilon$-entropy or Kolmogorov widths.

A problem of estimating a functional parameter t(x) and functionals Φ(t) based on observation of a solution ue(t, x) of the stochastic partial differential equation du_{\varepsilon}(t) = \sum_{\vert k \vert \leq 2p}ak Dxkuedt + t(x)g(ue, t, x) + edw(t) is considered. The asymptotic problem setting, as the noise intensity e → 0, is investigated.

Direct oxidation into sulfur in a pseudo-fluidized bed of spherical catalyst is a selective method of treating hydrogen sulfide-containing gases (HSCG) [1]. In contrast to the Claus method, it can be used for treating gases with a wide range of hydrogen sulfide contents [2]. “Acid” (as in Claus units) and hydrocarbon-containing (casing-heated petroleum, natural, refinery) gases can be treated with this method [3].

We solve the problem of extrapolation of an analytic function of a certain class in the case where its values are observed in a white noise whose intensity is not high.

As in Part I (see [I.~A.~Ibragimov and R.~Z.~Khas'minskii, {\em Theory Probab. Appl.}, 43 (1999), pp.~370--387]), we consider the problem of estimation of functional parameters $a_k(t,x),\,\theta(t,x)$ by observing a solution $u_\varepsilon(t,x)$ of a stochastic partial differential equation $$ du_\varepsilon(t)=\sum_{|k|\le 2p}a_kD_x^ku_\varepsilon+\theta\,dt+\varepsilon\,dw(t), $$ where $w(t)$~is a Wiener process. We investigate problems of the existence of consistent estimates for $\theta$ and their rate of convergence to $\theta$ dependent on properties of the functional class $\Theta$, which a priori contains~$\theta$.

The classical Cramer-Rao inequality is proved for a wider class of loss functions. Bibliography: 4 titles.

(2007). Measuring stresses in welded joints by the remagnetisation loss method. Welding International: Vol. 21, No. 2, pp. 139-141.

February 27, 2007, was the 75th birthday of the eminent mathematician, Professor Vladimir Mikhailovich Zolotarev. In 1949, Vladimir entered the faculty of mechanics and mathematics of Moscow State University. As his specialization field he chose probability theory and began his studies under the supervision of Eugene Borisovich Dynkin. After graduating from the university he was recommended to graduate studies, where his advisor was Andrei Nikolaevich Kolmogorov. Other distinguished mathematicians also have had a potent effect on Zolotarev's mathematical talent. Later, he mentions more than once not only his teachers E. B. Dynkin and A. N. Kolmogorov, but also B. V. Gnedenko and Yu. V. Linnik. In his graduate studies, Vladimir begins to study the properties of stable distributions. He continues to be interested in this theme even today. At first he was dealing with the stable distributions in the scheme of summation of independent identically distributed random variables. Later, he extended the concept of...

UDC 66.015.23+66.71 It is established on the basis of analysis performed by the Autonomous Union TsKBN and comparison of contact gasdrying equipment that the construction of the direct-flow/centrifugal element makes it possible to increase the velocity factor of the gas in a section of the apparatus to 6 as a result of utilization of the energy of involuted gas flow [1]. It is also established that the efficiency of the element can be improved by dispersing the liquid directly in the element, i.e., on contact between the liquid and gas in a direct-flow contact-separation element with recirculation of the liquid in the element. The liquid separated in the element falls onto a plate deck, from where it proceeds again into the element for contact with the gas; excess liquid overflows onto the underlying plate. The Autonomous Union TsKBN has developed a direct-flow contact-separation element [2], in the central section of which an ejector pump is installed to disperse the liquid and reduce gas entrainment in the drops of liquid. The liquid is fed into the ejector pump from beneath, while a preliminarily involuted gas flow strips the liquid, dispersing a certain size of droplet. Liquid for the contact with the gas flow is therefore fed directly into a region of reduced pressure; this provides for an increase in liquid feed to the element as gas consumption increases. Mass exchange in the contact zone (surface area of interphase contact) depends heavily on the point of entry of the liquid phase to the contact zone, which is located at the center of the involuted gas flow in the indicated design. In centrifugal mass-exchange elements with both a central, and peripheral liquid feed, the gas breaks the liquid up into