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The problem of two-layer convective flow of viscous incompressible fluids in a horizontal channel with solid walls in the presence of evaporation is considered in the Oberbeck-Boussinesq approximation assuming that the interface is a thermocapillary surface which is not deformed and taking into account the Dufour effect in the upper layer which is a mixture of gas and liquid vapor. The effects of longitudinal temperature gradients at the boundaries of the channel and the thicknesses of the layer on the flow pattern and the evaporation rate are studied under specified gas flow conditions with no vapor flow on the upper boundary of the channel. It is shown that the long-wavelength asymptotic behavior for the decrement is determined from the flow characteristics, the long-wave perturbations occurring in the system decay monotonically, and the thermal instability mechanism is not potentially the most dangerous.

The qualitative and quantitative composition of 13 polycyclic aromatic hydrocarbons (PAHs) in samples of snow waters on the territory of Novokuznetsk city and the Novokuznetsk district experiencing the maximum load on the environment from the activity of the enterprise of ferrous metallurgy was determined. The distribution of PAHs between the solid and liquid phases of snow water was studied by the method of high performance liquid chromatography (HPLC). It was shown that from 81.2 to 99.5 % of the total content of PAH was present in the solid phase of snow water. The concentration of benzo(a)pyrene amounts the value from 0.092 to 0.748 μg/dm³. It was established by the laser granulometry method that 90 % of particles of solid atmospheric aerosol in the snowpack were represented by particles, the sizes of which do not exceed 51.0 μm. Samples of snow waters are mainly characterized by the bimodal distribution of nanoparticles by sizes, the bulk of particles (up to 93 %) have the size of 400-600 nm, 7-9 % falls on the proportion of nanoparticles with the sizes of 44-86 nm.

Palladium in the concentration of 0.04-0.5 mass % was deposited on carbon nanofibres with the stack structure. The state of finely dispersed palladium nanoparticles deposited on the carbon nanofibres was studied by physical methods. Decrease of the concentration of supported palladium on the carbon nanofibres below 0.2 mass % led to the stabilization of the metal in atomic state. It was found that palladium nanoparticles in the atomic state were responsible for the high selectivity of the catalyst in acetylene hydrogenation to ethylene. Doping of carbon nanofibres by nitrogen atoms substantially alters the properties of supported palladium nanoparticles. The activity of the catalysts decreases whereas their selectivity substantially increases

Diesel engines are responsible for emission of particulate matters in industrial cities. Soot particles or particulate matters in diesel exhausts contain solid carbon, adsorbed organic compounds from the unburned fuel and products of its partial oxidation, as well as inorganic compounds, e. g ., sulphate ions, water and incombustible mineral residue. Soot has a strong affect on ecology in general and on human population health. This minireview presents the information on the state of the art for soot removal from diesel exhausts, as well as the modern trends and recommendations. Soot particles can be removed from diesel exhausts using coagulation and precipitation methods, which do not have required efficiency. Application of soot filters with catalytic coating is known to be more effective. Pt-based catalytic washcoats ensure soot oxidation by oxygen at 550-650 °C. NO _x addition makes it possible to decrease the soot oxidation temperature to 300-400 °C over Pt catalysts and Cu-containing zeolites.

The DNA damage in peripheral blood lymphocytes in employees of Kuzbass coal enterprises and men, non-exposed to the coal dust, was studied. In total, 501 donors were included in our research (137 coal miners, the average length of service is 28 years and 104 thermal power plant workers, the average length of service is 25 years). The average concentration of coal dust in miners’ workplace reached to 190 mg/m³, the content in power plant workers varied from 11 to 23 mg/m³. As a control group, 260 non-exposed men of similar age living in the same area were studied. Their blood samples were obtained from the ulnar vein. Cell cultivation, slides preparation and chromosomal aberrations assessment were performed in a similar way for all groups. It was shown, that the frequency cells with chromosomal aberrations in coal miners and thermal power plant workers was significantly increased compared to the control. Increasing the frequency of chromosomal breaks (chromosome as well as chromatid type) and chromosome exchanges was registered. The results obtained are the evidence of the expressed genotoxic exposure in the workers occupationally associated with the coal dust.

Associations between the increase in the number of hospitalizations for primary myocardial infarction and increased levels of oxide and nitrogen dioxide in the winter period compared to the summer period were revealed. It was found that during the entire observation period the increase in the concentration of nitrogen oxide in 10 % of the MPC increases the number of hospital admissions for MI by 1.4 cases and excess concentration of nitrogen dioxide by 0.9 cases. In winter period the excess of the average concentration of nitrogen oxide by 10 % of the MPC was associated with an increase in the number of hospitalizations by 2.9 cases. Thus, there is a relationship between the frequency of hospitalizations of patients with primary myocardial infarction and environmental pollution (the increase of the concentrations of oxide and nitrogen dioxide, phenol in the air). This pattern is more striking manifestation in winter period.

In continuation of works on toxicology of nanocarbon materials, investigations of safety of colloidal gold nanoparticles in the 10 to 40 nm size range in two lines of mice (outbred and line C57BL/6j) were performed. It was shown that in 24 h and 30 days after a single parenteral injection of colloidal gold nanoparticles in mice, the toxic action on indicators of peripheral blood, behaviour of animals, as well as internal organs was not revealed.

A cross-sectional retrospective passive epidemiological study for pediatric population aged 0-17 was performed using stratified random sampling. Children with hemodynamically significant congenital heart disease (CHD) in the period from 2005 to 2012 were identified using the official statistical database of the Department of Public Health in the Kemerovo region. In addition, a prospective study of 188 children with hemodynamically significant CHD admitted to the Department of Pediatric Cardiology at the Kemerovo Cardiology Dispensary was conducted. The average incidence of hemodynamically significant CHD in the large cities with ¹³⁷Cs contaminated soil surface layers was significantly higher compared to that rate in the cities of the Kemerovo region, where the surface layers of intact soils are not contaminated with radioactive cesium ( T _gr (av.) = +13.24 %; 95 % CI [9.25, 17.23] vs. T _gr (av.) = +5.31 %; 95 % CI [1.54, 9.07]; p < 0.05). Positive associations have been found between the risk of CHD in the next generation and the HLA-DRB1*11 and HLA-DRB1*03 allele in the female, the HLA-DRB1*07 allele in the male and a combination of HLA-DRB1*11 in the female and HLA-DRB1*01 in the male.

X-ray powder diffraction is one of the most potential characterization tools and a nondestructive technique for characterizing carbon based materials and their composite properties. The method is used to measure phase identification, quantitative analysis and to determine structure imperfections of samples. The paper summarizes results of investigations of carbonaceous materials structure. X-ray diffraction is used as the technique for characterizing the structural order. As it turned out the carbonaceous materials obtained by the low-temperature graphitization of coal-tar pitch contain contemporaneously several phases of crystalline carbon and amorphous carbon with turbostratic structure. In the present report, to explain the heterogeneous structure of carbonaceous materials we compare data of X-ray diffraction analysis for the (00l) reflection from the main crystal face. It was found that the (002) and (004) reflections are the superpositions of components, which correspond to the structural phases of crystalline carbon and amorphous carbon with different interplanar spacing. The ratio between the integrated intensities of separated reflection components accounts for the ratio between these phases; along with interplanar spacing, this ratio characterizes carbonaceous materials and makes it possible to detect difference between them. The degree of ordering, the interlayer spacing ( d ₀₀₂), and the crystalline sizes ( L _a and L _c) are considered the key parameters for evaluating the stacking structure of carbonaceous materials.

The absorption and scattering efficiencies, albedo and anisotropy factor values were calculated for soot particles in water and pentaerythritol tetranitrate media for different radii in terms of Mie theory. The main features of the calculation results include (i) the domination of absorption over scattering and (ii) the change of attenuation dependence on the wavelength trend at particle’s radius about 150 nm. For smaller particles the attenuation efficiency decreases with wavelength increasing while for bigger ones the trend is just opposite. The soot particles in the experimental part of the work were characterized with dynamic light scattering. The obtained size-distribution is fit well with log-normal distribution having particles’ radius expected value 183 nm. The spectra of total transmittance, ballistic transmittance and diffuse reflectance were measured for studied soot suspension in water. It was shown that the total transmittance does not depend significantly on the wavelength while the diffuse transmittance decreases twice with the wavelength increasing. It is concluded that the calculation results qualitatively agree with the experimental data if the typical particle’s radius is twice smaller than one obtained with dynamic light scattering method. The possible applications of obtained optic properties of soot particles for special devices including optic detonator cups are discussed.