Stochastic laser-beam transfer through a binary Markovian mixture

We present an approximate analysis of a stochastic laser-beam transfer through a scattering two-component Markovian mixture. We also compare this transfer with a transfer of the beam through an equivalent uniform medium. The problem is considered by use of the so-called small-angle approximation. Within the framework of our approach we obtain some sets of differential equations, defining a total transferred energy and an effective beam size. Our results show that transfer of laser radiation through binary Markovian media differs considerably from transfer through uniform media.     

Granulated sorbents from wood waste

An integrated study of various wood-utilization wastes as raw materials for the production of carbon adsorbents was performed. A technology was developed, and granulated sorbents from various wood wastes were prepared and characterized. The regularities of pore-structure formation and the physicochemical properties of sorbents were found depending on the used raw material, binding agents, granulation conditions, and the process parameters of the thermal treatment of granules.     

Magnetic anisotropy induced by stress annealing,its thermal stability,and structure of the Fe<Subscript>5</Subscript>Co<Subscript>72</Subscript>Si<Subscript>15</Subscript>B<Subscript>8</Subscript> alloy

The efficiency of the magnetic-anisotropy induction in the Fe₅Co₇₂Si₁₅B₈ amorphous alloy during its thermomechanical treatment and the thermal stability of the anisotropy are shown to depend on the structural state of the alloy. Structural inhomogeneities (microinhomogeneities and preprecipitates) formed in the structure of the amorphous alloy upon annealing at 350–430°C increase both the efficiency of the magnetic-anisotropy induction in the course of subsequent heat treatment at 290°C combined with tensile deformation and the thermal stability of the anisotropy.     

Determination of chromium (VI) using cathodic voltammetry technique in gold microelectrodes

Electrochemical reduction of chromium (VI) is studied on a gold microelectrode assembly (Au-MEA) using the cathodic voltammetry (VA) technique. The optimum conditions for obtaining the analytical signal of Cr (VI) are chosen. The range of the analyzed concentrations of Cr (VI) are 0.005?C0.2 mg/L, and the detection limit is 5 × 10^?5 mg/L. Dissolved oxygen, manifold excesses of alkali and alkaline-earth ions, 200-fold excesses of Cr (III), and 10-fold excesses of Fe (III) and Cu (II) do not interfere with determination of 0.005 mg/L Cr (VI). In the presence of anionic surfactants (DDCNa), the signal of Cr (VI) decreases, but the linear dependence on the concentration remains. A rapid technique for determination of Cr (VI) in purified technical water without sample preparation is suggested. The advantage of Au-MEA consists in the simplicity of synthesis, running time, high sensitivity.     

Phase Composition of the Products of Fe Oxidation in Fe + C + NaCl + H2O + O2 Exothermic Mixtures

Using thermodynamic analysis of the Fe–C–NaCl–H₂O–O₂ system and experimental studies (x-ray diffraction and Mössbauer spectroscopy) of exothermic mixtures containing Fe metal, activated carbon, water, and NaCl, we identified the state of Fe and determined the phase composition of the reaction products at different stages of oxidation with atmospheric oxygen. The calculation and experimental results are in reasonable agreement. Under the conditions of restricted access for air, the main oxidation product is magnetite, Fe₃O₄. Free access for air leads to the formation of hydrous ferric oxide, Fe₂O₃ · nH₂O. The most stable phase under the conditions of interest is goethite, Fe₂O₃ · H₂O (-FeOOH). Storage of incompletely oxidized samples away from air for 7–14 days leads to partial reduction of iron(III) oxide phases to Fe₃O₄ and -Fe.     

Multi-Purpose Use of Caustobioliths of Carbonic Series Based on Innovative Coal Chemistry Technologies in the Far East of Russia

The current technologies available in the world market for the chemical processing of caustobioliths of carbonic series are overviewed. The prospects for the expansion of the coal supply base in the Far East of Russia are discussed, and the main lines of advancement in the coal preparation industry are specified. It is possible to arrange coal chemistry clusters in the Amur Region (thermal conversion of coal, production of Montana wax and oxidized humite), in the Khabarovsk Territory (in-situ gasification) and in the Primorye (motor fuel and liquid fuel production).     

Evaluation and modification of the initial composition of gabbro-basalt rocks for mineral-fiber fabrication and stone casting

Literature data and calculation results demonstrate that it is appropriate to use the acidity coefficient for the initial evaluation of the properties of gabbro-basalt raw materials for fiber production and stone casting. We examine the capabilities of hydrochloric acid leaching for modifying the composition of raw materials and those of physicochemical calculations for determining the mineralogical compositions of raw materials and modification products.