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Experiments on the rotating in the air cones with vertex angle β = 120º and flat disc shown that on frequencies Ω ≥ 2.5 hertz exists a qualitative difference in movement for the particles with diameters d ≈ 1 mm and d ≈ 0.1 mm. The particles with d ≈ 0.1 mm move in the near-surface region, the particles with d ≈ 1 mm jump up to 3 cm. Comparison of the spherical and aspheric (ellipsoid with axles d, d and 4 /3 d) particles' kinematics moving shown the inevitability of the large particles jump occurrence. Large particles come to self-oscillation regime by reason of periodically appearance of the Magnus force. Small particles are localized in the velocity layer

We studied the effect of oxidation temperature and initial hydrogen concentration on the occurrence of cubic (δ) to tetragonal (e) phase transformation induced by thermal oxidation of titanium hydride powders in air. X-ray diffraction analysis indicates that δ → e transformation occurs during oxidation at 400 °C, but not at lower (300 °C) or higher (500 °C) oxidation temperatures. The relative amounts of hydrogen loss during oxidation were determined by temperature-programmed desorption mass spectrometry (TPD-MS). The findings suggest that oxygen stabilizes the tetragonal phase (e), and that the δ/e phase composition following oxidation depends on both oxygen and hydrogen concentrations. For high oxidation temperatures (500 °C), some degree of hydride decomposition leads to a decrease in H concentration and to destabilization of the tetragonal phase after cooling down to room temperature.

The effect of the structural transformations during non-vacuum electron-beam cladding of amorphous boron powder on the hydroabrasive wear resistance of the surface layers of a chromium-nickel austenitic steel is studied. It is shown that the cladding yields a coating with densely arranged borides. An x-ray method is used to show that the modified layer consists virtually fully of Fe2 B iron borides. This structure raises the hydroabrasive strength of steel 12Kh18N9T by a factor of 1.5 – 2.

A method for producing a series of metal glycolates and cellosolvates, which are promising materials for the sol-gel and pyrolytic technologies for fabrication of powders and thin-layer oxide coatings by dissolution of metals in glycols and cellosolves in the presence of gallium trihalide as catalysts, is discussed. The dependence between catalytic activity of halides and the anion used is revealed.

We have studied reactions of metallic magnesium with ethyl cellosolve and a mixture of ethyl cellosolve and tetraethyl orthosilicate and demonstrated the possibility of preparing a mixed magnesium–silicon cellosolvate that can be used as a precursor for the synthesis of forsterite and enstatite.

Possibility of deep purification of lower aluminum alcoholates used to synthesize aluminum oxide by the sol-gel method and pyrolytic technique is analyzed. The influence exerted by the purity of the starting reagents, moisture content, and catalyst on the nature of the process and the purity of the product being obtained was examined.

Thermodynamic aspects of the H-C-Cl-Si system are considered in the temperature range of 700–1500 K. It is shown that a mixture of compounds containing alkylchlorosilane monomers can form under these conditions.

The wear of steel plates under the impact of a hydroabrasive jet was studied experimentally by varying the distance between the sample surface and the nozzle, the angle of impingement of the jet on the plate, and the abrasive concentrations in water and in the ambient medium (jet in air, submerged jet). The results are compared with available data on the structure of the jet and jet flow around an obstacle. It is shown that the addition of abrasive particles to the liquid can be used to study the liquid jet flow around an obstacle because the form of surface wear allows one to determine the region of impact of the jet core, the deceleration region, and the near-wall flow region before flow separation.

The influence exerted by hydrolysis methods and introduction of a hydrolyzing agent into the systems formed by the alkoxide technology, which uses yttrium salts and alumium secondary butylate as the initial components, was determined. It was found that the hydrolysis stage affects the conditions of the subsequent thermal treatment, the phase formation in the system, and the granulometric composition of the prepared powders. The most favorable conditions for formation of yttrium aluminum garnet are achieved upon excess water hydrolysis in the presence of an aqueous solution of yttrium salt.

Purification of a number of silicon derivatives (chloride, lower alcoholates) formed in processing of high-purity silicon for electronic and electrical industries was considered. It was found that high-purity substances suitable for use in electronics and optics can be produced from industrial wastes.

We considered a deep cleaning of 1,1,1,3,3,3-hexamethyldisilazane used in microelectronics and organoelement synthesis from a series of homogeneous and heterogeneous admixtures by various physicochemical methods.

Method for evaluation of the efficiency of photoresist adhesion promoters is suggested. The method is based on a thermodynamic simulation of the reactivity of organosilicon compounds with respect to hydroxycontaining derivatives. The adequacy of the chosen technique was verified experimentally.

The features of the world market of rare and scattered metals (RSM) are considered, and trends in its development that have manifested themselves in recent years (2004–2007) are analyzed with an allowance for variations in the existing market conditions and the appearance of new factors, which need to be taken into account in an analysis of the world and Russian markets of RSM for the nearest future.

A number of aspects associated with the synthesis of high-purity compounds used in the gas-phase and sol-gel methods for preparing coatings and finely dispersed powders of oxides and oxide composites are considered.

We have developed a software system, which is able to predict the motion and destruction of space objects of arbitrary shape entering the Earth's atmosphere. It was named SCARAB (‘Spacecraft Atmospheric Re-entry and Aerothermal Break-up’). The software uses a modular approach, combining flight dynamics, aerodynamics, aerothermal and thermal analysis, as well as structural analysis. Each module uses engineering methods to keep the total computational expenditure for the complete simulation within acceptable limits. Thermal and structural analysis provide criteria for the destruction of a traced object. If there Me fragments left after a destruction event, each part can be traced separately until all parts of the original spacecraft are destroyed or have reached ground. The software has been applied to several test cases with and without destruction. Some results have been compared with in-flight measurements, other results were compared with other existing re-entry prediction tools. Additional applications to complicated satellites (ERS-1, ENVISAT) and other objects of general interest (ATV, small debris parts) are currently under way and exemplary results are presented in this paper.

Methods for producing optically transparent ceramic materials based on Y2O3 using carbonate and alkoxy precursors are considered. It is established that ceramic synthesized from yttrium isopropylate has better optical parameters than ceramics based on yttrium carbonate under equal heat treatment and firing regimes.

Niemann-Pick type C (NPC) disease is a rare autosomal recessive lysosomal storage disease, exhibiting an extremely heterogeneous clinical phenotype. It is a cellular lipid trafficking disorder characterized by the accumulation in the lysosomal/late endosomal system of a variety of lipids, especially unesterified cholesterol. So far two genes, NPC1 or NPC2, have been linked to the disorder. It is a panethnic disease for which two isolates have been described. We present a novel NPC1 mutation (p.A1132P; c.3394G>C) identified in homozygosity in two patients originating from the same small town of an Aegean Sea island and the results of the broad screening of their extended families. Overall 153 individuals have so far been investigated and a total of 64 carriers were identified. Moreover a common descent of the individuals tested was revealed and all carriers could be traced back to a common surname, apparently originating from a common ancestor couple six generations back. The mutation was found associated with an uncommon haplotype in the island that is also present in other populations. © 2013 John Wiley & Sons A/S.

The company Tagmet makes steel in 290-ton open-hearth furnaces by the pig-and-scrap process, tapping the metal into two ladles. The steel is then treated on a two-position “ladle-furnace” unit equipped with a pinch-roller system to introduce cored wire and aluminum wire rod. After the steel has been brought to the desired temperature and chemical composition on the unit and treated with calcium-bearing wire in the final stage, it is bottom-poured into circular tube ingots weighing 1.2‐2.0 tons. In connection with the recent exploitation of gas fields that contain hydrogen sulfide, the pipes used in the equipment for the wells and the gas lines are having to meet higher standards on their content of harmful impurities and nonmetallic inclusions ‐ which affect the physicochemical properties and corrosion resistance of the metal. It is known that micro-additions of different materials to steel can decrease its sulfur content by raising the level of deoxidation of the steel and the refining slag and providing for fuller use of the slag’s sulfide capacity [1]. It has been es tablished that the addition of calcium makes it possible to obtain steel with sulfur content of 0.005% or less [2, 3], and it helps more favorably distribute phosphide eutectics in the steel [4]. The addition of calcium to steel in the needed amount ‐ the amount of calcium being determined by the steel’s content of oxygen, sulfur, and aluminum [3] ‐ helps transform nonmetallic inclusions and convert hard aluminates into globular low-melting calcium aluminates. Proceeding on the basis of the above, Tagmet has developed and introduced a technology for micro-alloying corrosion-resistant tube steels 35G2, 20SA, and other steels used for well casing and drill pipe. The steels are micro-alloyed with a specified amount of calcium-bearing cored wire introduced by a pinch-roller system at a rate of 3‐3.5 m/sec. The wire and the steel are then mixed for 3‐5 min to average out the chemical composition of the latter and ensure that the nonmetallic inclusions rise to the surface of the melt. To study the effect of calcium on the transformation of nonmetallic inclusions in molten steel, we took samples of three heats of steel 20SA having nearly the same chemical composition in terms of their contents of the main elements, aluminum, and harmful impurities (sulfur and phosphorus). Standard procedures were employed on a ladle-furnace unit to obtain the samples with immersion-type samples before and after treatment of the steel (before it was cast). The normal practice was followed in finishing the steel with respect to temperature and chemical composition. Only the steel of two of the heats was treated with the calcium-bearing wire (Table 1). We used the samples to prepare metallographic sections for studying the composition of the nonmetallic inclusions. Thirty fields in all were examined. It was determined that, before the treatment, the nonmetallic inclusions in all three of the heats consisted of accumulations of aluminum spinel and sulfide eutectics present in the form of films along the grain boundaries. After its treatment, the steel of heat No. 1 contained almost no coarse accumulations of oxides (the oxides were probably assimilated by the slag), and the aluminate-type oxides that were precipitated were present in smaller clusters. The sulfides were precipitated in the form of eutectic colonies.

Characterization of coatings made with the help of Computer Controlled Detonation Spraying (CCDS) was performed. The applied coatings include hard alloys (WC/Co -75/25, WC/Co - 88/12, WC/Co/Cr - 86/10/4, and Cr2C3 / NiCr), aluminum oxide, nickel-chromium self-fluxing alloy, titanium, bronze, and stainless steel. Tribological investigations of coatings were provided using abrasion test (ASTM standard G65), erosion test (ASTM standard G76), and hydro-abrasive test. To make hydro-abrasive tests special device and method were elaborated based on the interaction of water jet saturated with corundum particles with a coating surface.

The high consumption of steam for process needs has led to location of oil refineries near heat and electric power plants (HEPP). However, the steam processed there is relatively expensive, which significantly affects the product cost and economic operating indexes of the enterprise. Moreover, process cycles and exhaust gases from different types of furnaces contain an enormous amount of physical heat. Preliminary calculations show that a significant part of the demand for steam can be covered by recovering this heat.

The component composition of nystatin produced by an improved strain of Streptomyces noursei was determined by HPLC on Milichrom chromatograph (USSR). It was shown that the antibiotic consisted of nystatins A1, A2, A3 and B and admixture substances. The data appeared to be in good agreement with the results of the complex TLC investigation, by using densitometry. The component composition of the samples was evidenced by SIEAP mass spectrometry. Physiochemical and biological characteristics of separate components are presented.

Reactions of levorin, a polyenic macrolide antibiotic, with aromatic aldehydes and hypophosphorous acid resulted in formation of its amino phenylphosphonium derivatives. Physicochemical and biological properties of the derivatives were studied. The levorin amino phenylphosphonium derivatives were shown to be low toxic and have antifungal and antiviral activities.

Although many zinc plants attempt to increase a fluidized bed roaster’s capacity by employing an oxygen-enriched air blast, work in the former Soviet Union shows the advantages of redesigning the roasting complex to optimize concentrate flow and process hydrodynamics. A redesigned furnace in operation for five years demonstrates, as compared to conventional Soviet furnaces, greater versatility, improved charge capacity, better heat recovery, ease of control, and operational stability.

An integral equation-method of moments technique is applied to the computer-aided design and analysis of the magnetic field controllers used for coma and spot distortion correction in color picture tube systems. An efficient strategy is developed for specifying very complex field controller geometries as combinations of rectangular, annular, and/or cylindrical subsections. Excellent correlation is obtained between calculated and measured magnetic fields for typical field controller configurations.

In the nature of non-staining antiozonants, a new class of compounds, 1,1,4-derivatives of thiosemicarbazide, are proposed. The mechanism of reaction of thiosemicarbazide derivatives with ozone is analogous to the mechanism of this reaction with thiourea derivatives. Within this, the rate constant of the initial reaction of the thiosemicarbazide derivatives with ozone is somewhat higher than that of the thiourea derivatives. 1,1,4-Trialkyl-substituted thiosemicarbazides appear to be the most effective antiozonants, not changing the color of light vulcanizates. Of the investigated compounds, 1,1,4-tributylthiosemicarbazide, being distinguished by a large protective effect against ozone, inhibiting activity in the process of heat aging of the vulcanizates, and lesser ability for leaching out of the vulcanizates by water than tributylthiourea, presents the greatest practical interest.