Features of Defect Formation in Nanostructured Silicon under Ion Irradiation

Semiconductors - Nanostructured silicon is irradiated by Si+ and He+ ions with energies of 200 and 150 keV, respectively. Destruction of the structure of irradiated samples and the accumulation of...     

Applying Plane Wave Imaging Technology in Ultrasonic Nondestructive Testing

Russian Journal of Nondestructive Testing - Along with such advantages as high resolution over the entire area of reflector image reconstruction and the ability to produce images taking into...     

Active Monitoring of Thermal Insulation Protection Status of Pipelines

Refractories and Industrial Ceramics - The article discusses the temperature regimes of transit pipelines for steam and hot water movement. A new device for thermal insulation of high-temperature...     

Interrelation of characteristics of blocked RMA stack algorithms

A method to analyze the duration of collision resolution for blocked RMA stack algorithms is proposed. Simple formulas are obtained that express the average length of a collision resolution interval for the modified (frugal) algorithm in a noisy and in a noiseless channel, as well as for the basic algorithm in a noisy channel, through the corresponding parameters for the basic algorithm in a noiseless channel. From estimates of the throughput of the basic algorithm in a noiseless channel, estimates for the throughput in the other three cases are directly constructed.     

Indirect electrochemical synthesis of active oxygen in dilute sulfate solutions

Anodic oxidation of dilute solutions of sodium sulfate was developed to generate oxidants into aqueous solutions with a diaphragm electrolyzer, which consisted of titanium anodes covered with mixed oxides of iridium, ruthenium and tin, a titanium cathode, and Teflon cation-exchange membrane. An electronic device was created for continuous self-purification of cathode surface from hardness salt deposits. The anodic products of electrolysis were molecular oxygen and sodium persulfate. It should be noted that sodium persulfate was the only active oxidant. The synthesized anolyte was tested for its oxidizing activity towards certain metabolites and toxicants. Disinfecting properties of anolyte were detected towards gram-positive and gram-negative bacteria. The comparison of redox potentials of commercial samples of persulfate and the synthesized anolyte showed that the redox potential value for the anolyte is much higher than for solutions with the same concentration of commercial persulfate.     

Explicit finite difference method in the dynamic analysis of composite structures

An approach for numerical analysis of composite thin-walled structural elements is presented. The analysis is based on the applied theory of composite shells and the grid-characteristic method of finite differences. The explicit and stable homogeneous method for numerical integration of dynamic equations of thin-walled composite structures is discussed. The splitting procedure is used to extract strongly oscillating components from the solution. Implementation of this procedure provides the stability of explicit finite differences schemes. The method considered makes it possible to carry out computations for a wide range of variation of structural parametres and could be used for the analysis of composite structures under dynamic loading.     

An assessment of a revised Olmo et al. model to predict solar global radiation on a tilted surface at Beer Sheva,Israel

A model to convert horizontal solar global radiation to that on a tilted surface is presented. It is based upon a relatively simple model proposed by [Olmo FJ, Vida J, Foyo I, Castro-Diez Y, Alados-Arboledas L. Prediction of global irradiance on inclined surfaces from horizontal global irradiance. Energy 24 (1999) 689–704]., which requires only measurements of horizontal solar radiation but was found to produce significant errors when tested with data from another site. The present model assumes the availability of databases for at least two of the three solar radiation types, viz., global, beam and diffuse. The horizontal global radiation is converted to that on a tilted surface by applying the Olmo model to the diffuse component, whereas the beam component is converted by using the geometrical relationship between the two surfaces. The original Olmo anisotropic radiation correction factor is now assumed to be a function of sky conditions. The solar radiation databases were converted to subsets corresponding to clear, partially cloudy and cloudy sky based upon clearness index values. The three anisotropic correction factors were determined by fitting to a 12-months database. The present model was then tested by applying it to a second database consisting of 24-months not involved in the model development. It was found to give better results than three highly regarded more complex models.     

Density functional modelling in multiphase compositional hydrodynamics

This work is essentially a review of a density functional approach in multiphase hydrodynamics developed by the authors during the last 15 years [Dinariev, J Appl Math Mech 1995;59(5):745–752; Dinariev, J Appl Math Mech 1998;62(3):397–405; Demyanov and Dinariev, Fluid Dynam 2004;39(6):933–944; Demianov et al., “Basics of the Density Functional Theory in Hydrodynamics,” Fizmatlit, Moscow; 2009 (in Russian); Dinariev and Evseev, Fluid Dynam 2010;45(1):85–95]. The basic assumption is a representation of the entropy or the Helmholtz energy of the mixture as a functional that is dependent upon chemical component densities. The hydrodynamic system of equations (local conservation laws for chemical components, momentum, and energy) is used to describe multiphase processes, and the constitutive relations (expressions for stresses, diffusion, and heat fluxes) are derived from entropy growth requirement. The authors present the results of numerical simulations describing static and dynamic multiphase systems.