Production of a new generation of diesel fuels by hydrotreating a mixture of petroleum and plant feedstock

Hydrotreating of mixed crude oil based on petroleum distillate of diesel fuel with a different content of unrefined cottonseed oil was investigated. The major possibility of utilizing plant feedstock in production of diesel fuels of improved quality and simultaneously increasing their supply due to this was demonstrated.     

Dimensional method for investigating convective heat exchange processes in solar collectors

The basic criterial formulas are presented for calculating heat exchange in the heat removing channels of solar water collectors (SWC) with known coefficients in the equations.     

Liquid-Phase Oxidation of Oil Hydrocarbons in the Presence of Nanostructured Mn-Containing Catalyst

The liquid-phase oxidation of a naphthene-paraffin concentrate obtained from a mixture of Azerbaijan oils is studied in the presence of a nanostructured Mn-containing catalyst with a carbon basis. It is found that the catalyst system represents a dispersion medium containing catalyst particles with a hydrodynamic diameter of 0.5–1.3 µm. It is shown that the catalyst can be used for the production of carboxylic acids with yields as high as 42.9%.     

Inhibitive and bactericidal effects of natural naphthenates on steel corrosion in sea water

The inhibitive effects and interfacial tensions of solutions of natural naphthenates in the passivation of the steel surface in sea water were studied by electrochemical and stalagmometric methods. According to the data obtained, Ca²⁺, Ni²⁺, and Co²⁺ naphthenates suppress the anodic and cathodic polarization of steel. The biocidal effects of the naphthenates in sea and stratal waters were determined. It was found that treatment of sea water with calcium naphthenate protects steel equipment from both electrochemical and microbial corrosion. Original Russian Text ? A.M. Samedov, L.I. Alieva, V.M. Abbasov, 2008, published in Fizikokhimiya Poverkhnosti i Zashchita Materialov, 2008, Vol. 44, No. 4, pp. 427–431.     

Theory of high-gradient magnetic filter performance

A unique general model for high-gradient magnetic filters is presented. The functional dependence of the filter performance on the system's physical and geometrical parameters is derived. The derived theoretical expression makes it possible to explain both of the two different, apparently opposite, experimental results reported in the literature. The new quality factor does not include the suspension viscosity, but instead depends on the suspension density, which leads to the application of the formula for a larger class of filtration media including liquids, gases, and vapors     

Petroleum acids and corrosion

The current state of research in petroleum acid corrosion of metals is surveyed. It is shown that the corrosion of refinery equipment caused by petroleum naphthenic acids is a multifactor process. The general characteristics of the acid content in crude oils and the acid number give quite a rough evaluation of the corrosive power of oils, and the determining factors useful for evaluation are the type, structure, and functionality of petroleum acids. Effective ways of preventing petroleum acid corrosion of metals are comprised of the demineralization and careful alkali treatment of crude oil, the use of organic corrosion inhibitors, and improvement in the metal quality by alloying with anticorrosive additives. Methods for simulation of the metal corrosion processes caused by petroleum acids are becoming of substantial importance.     

Optimal location of internet data centers taking into account the risks

In this paper, a model for location of Internet data centers taking into account the risks due to natural, political, economic, and other factors is proposed. The risks are presented using fuzzy linguistic variables. At the end of the article, a numerical example is given.     

Structure and principal electrophysical properties of Ge<Subscript>1 − <Emphasis Type="Italic">x</Emphasis></Subscript>-Si<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> thin films

In the process of thermal treatment of deposited Ge_0.85Si_0.15 films, a number of peculiarities were found related to the character of their conductivity. The films of Ge_0.85Si_0.15 solid solutions are rather resistant to thermal quenching. It was shown experimentally that irradiation with electrons under an accelerating voltage enhances the crystallization in the films and lowers their electric conductivity.     

Hydrodynamics and heat exchange in water suntraps

Heat exchange in water suntraps (WS) is discussed. It is shown that the heat exchange and the hydrodynamic characteristics of the flow in the initial sections of the heat removal channels of the WS can be calculated with the help of the laminar boundary layer model, using the assumptions adopted in boundary layer theory.