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Metal-carbon materials M/CNTs (M = Ce, u, Mo) were synthesized by incipient wetness impregnation and their physicochemical characteristics were studied using various methods (inductively coupled plasma optical emission spectrometry, thermal analysis coupled with mass spectrometry, low-temperature nitrogen adsorption, X-ray diffraction and structural analysis, scanning electron microscopy, and Raman spectroscopy). It was found that M/CNTs (M = Ce, u, Mo) are the mesoporous materials consisting of carbon nanotubes with deposited eO2, u2O/Cu or 3/MoO2 particles, respectively. The dispersion of supported species and their deposition uniformity improve in the series u < <. The type of metal was shown to affect thermal stability as well as the textural and structural properties of the samples. The thermal stability of materials increases in the series Ce < Cu Mo, which is caused by different redox properties of the metals and also by the composition of products of the metal precursor decomposition. It is promising to use the developed materials as the catalysts for deep purification of diesel fraction components from sulfur compounds. [ABSTRACT FROM AUTHOR]

The role of acid treatment of Taunit carbon nanotubes in the formation of oxygencontaining functional groups on its surface as well as morphological and textural properties was studied. Acid treatment was carried out in an HNO3 solution or its mixture with H2SO4 under mild conditions (85 °C/1 h) with subsequent washing with distilled water or without washing. Properties of the initial and oxidized samples were investigated using elemental carbon, hydrogen, nitrogen, oxygen (CHNO) analysis, BET (Brunauer-Emmett-Teller) determination of surface area, X-ray diffraction, Raman and Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy, and hydrogen temperature-programmed reduction. Treatment with HNO3 and HNO3/H2SO4 mixture was shown to be efficient for the formation of various oxygen-containing groups on the Taunit surface; therewith, the water washing step also contributed to functionalization of the surface. Depending on the oxidant, acid treatment increased graphite and oxygen content in the samples by a factor of 3-4.5. Treatment with HNO3 without water washing exerted a weak effect on the graphite structure ordering, the concentration of aliphatic groups was high as compared to other oxidation conditions. Treatment of Taunit with the HNO3/H2SO4 mixture, on the contrary, increased the number of defects in graphite layers and decreased the concentration of aliphatic structures. [ABSTRACT FROM AUTHOR]

To develop new catalysts based on carbon nanomaterials with supported metal oxide nanoparticles for oxidative transformations of sulfur compounds, a series of metal oxide nanoparticle-decorated carbon nanotubes (MOx/CNTs) were prepared by incipient wetness impregnation at a variation of the active metal type (M = Ce, Mo, Cu). The thermal decomposition of bulk and CNT supported metal precursors used in the preparation of MOx/CNTs was analyzed under inert atmosphere employing several thermoanalytical techniques (thermogravimetry, differential thermogravimetry and differential scanning calorimetry) coupled with mass spectrometry. The thermolysis parameters of the bulk and supported metal precursors were compared and the effect of CNT support on the decomposition pattern of compounds was elucidated. It was established that the decomposition of metal precursors supported on CNTs was started and completed at temperatures of 15-25 and 25-70 °C lower, respectively, compared with the bulk active metal precursor. The enhancement of CNT support stability against thermal degradation is observed in the following row of metal cations: Ce < Cu < < pristine and metal anions of precursor: nitrate < chloride < sulfate. The optimal mode of thermal treatment of catalyst and appropriate active metal precursors were selected for advanced synthesis of nanosized MOx/CNT catalyst. [ABSTRACT FROM AUTHOR]

The Sverdlovsky region takes the fourth place among the 89 subjects of the Russian Federation by the number of registered cases of HIV infection. Drug addiction has reached an excessive scale in this region: according to the data of express evaluation carried out by the Regional Narcological Hospital and the Regional AIDS Center, not less than 7-8% of persons aged 15-30 years constantly use injection drugs. The large-scale epidemic of injection drug addiction has led to the rapid spread of HIV among addicts. The first penetration of HIV into this population took place in 1996 and, starting from the year 2000, rapid, development of the epidemic began, taking the character of an avalanche. The peak of new cases of HIV infection fell on 2001 (9,230 cases were registered). The concentrated stage of the epidemic development is observed in the region at present, the prevalence of HIV infection among drug addicts being 13.8%. Children born from HIV-infected drug addicted mothers now represent a new risk group due to great difficulties in the prophylaxis of the vertical virus transmission.