Home – Home – Jornals – Chemistry for Sustainable Development 2016 number 4

The results of aircraft and near-ground investigations of the spatiotemporal variability of aerosol and black carbon (BC) concentrations in the troposphere for the last two decades are reviewed. Since 1999, the airborne sensing of vertical profiles of BC and aerosol concentrations in troposphere up to a height of 7 km in the regions of West Siberia and Russian Subarctic had been carried out onboard flying laboratories. Since 1997, the Aerosol Station in Tomsk conducts monitoring measurements of the aerosol and BC concentrations in the surface layer. The data of airborne sensing were used for analysis of common and distinctive features of the spatial variability of vertical profiles of aerosol and BC concentrations, ВС fraction, single scattering albedo (SSA) in the visible. The integral BC concentration and aerosol optical thickness in the column of the atmosphere were obtained for the first time. The classifications of typical optical and microphysical states of the subarctic troposphere have been performed for: 1) high transparency of air in the polar latitudes; 2) strong impact of Siberian forest fires in warm season; 3) conditions of regional average background atmosphere in the middle latitudes. As the latitude increases in the range of 55-75.2°N, the near-ground aerosol and BC concentrations decrease threefold, on average. In the subpolar latitudes, a tendency to decrease of the concentrations in the direction from the west (Kara Sea) to the east (Eastern Subarctic) is observed. The generalized empirical model of the tropospheric aerosol in middle latitudes of West Siberia for cloudless atmosphere had been developed for the first time and allows calculating the seasonal average vertical profiles of SSA needed for estimation of the direct climate impact of aerosol. The main features of diurnal, seasonal, and inter-annual dynamics of BC and aerosol concentrations, and BC fraction have been studied for the near-ground measurements and parameterization of these dependences are performed.

The distribution of atmospheric black carbon (BC) in the marine boundary layer of the North Atlantic and Baltic, North, Norwegian, Barents, White, Kara and Laptev Seas was studied in research cruises with the RV “Akademik Mstislav Keldysh” during July 23 to October 24, 2015. Air was filtered through Hahnemuhle Fineart Quarz-Microfibre filters. The mass of BC on the filter was determined by the measurement of the attenuation of a beam of light transmitted through the filter. Source areas were estimated by backwards trajectories of air masses calculated using NOAA’s HYSPLIT model (http://www.arl.noaa.gov/ready.html) and FLEXPART model (http://www.flexpart.eu). During some parts of the cruises, air masses arrived from background areas of high latitudes, and the measured BC concentrations were low. Over other parts of the cruises, air masses arrived from industrially developed areas with strong BC sources, and this led to substantially enhanced measured BC concentrations. Model-supported analyses are currently performed to use the measurement data for constraining the emission strength in these areas.

In this work, features of an arrangement and localization of the main sources of soot emissions on the territory of Krasnoyarsk city are considered. It is shown that under the conditions of the complex orography, the circumstances to forming high urban air pollution levels by dust, soot and black carbon are created. Thus, the stationary sources of Krasnoyarsk city throw out in air 129.8 thousand t of the polluting substances a year. Emissions from the largest enterprises amount to 91.9 % of total amount (47.2 % - RUSAL Krasnoyarsk OAO and 44.7 % - Heat Electropower Stations Nos. 1, 2, 3). The proportion of soot in the total amount of emissions amounts to 3 %. But despite this, features of the emission sources arrangement on the territory of the city can form a considerable human health risk level.

The article presents a review of an online service ECCAD on the base of Internet database MACCity, on the base of which the pre-treatment was made and emission dynamics of black carbon was analyzed for the period of 1960-2015 for the region of Kola Peninsula by six types of sources (energetics, industry, industry, surface transport, marine transport, household use of resources and waste treatment). The data on the total black carbon emissions in the region over this period were given. The leading position in emissions of black carbon of the household use of the resources use and insignificance of the contribution of the region as a whole in Russia was noted.

The work presents concentrations of elemental carbon (ЕС) in atmospheric aerosol samples, collected on fibreglass aerosol filters in the Novosibirsk region, in the northwest of the Siberian region, and in the White Sea Region from 1999 to 2015 and measured by the method of reaction gas chromatography. The year-to-year progress, seasonal and daily variations of EC concentration at observation sites, as well as the influence of distant wood fires on the content of EC in the sites with different degrees of anthropogenic stress. The HYSPLIT model is used to estimate the sources of the formation of EC-containing aerosols.

In the work, the isotopic composition of pyrogenic carbon samples of various origins was studied. The dependence of this composition on the isotopic composition of the source carbon source was determined using isotope ratio a mass spectrometer DELTA V Advantage (Thermo Fisher Scientific/USA-Germany) in the combination with an elemental analyzer Flash-2000. The studies showed that pyrogenic carbon produced after burning kerosene and its derivatives (δ¹³С = -30 ‰) had the lightest isotope composition. The isotope composition of wood δ¹³С = -27 ‰, and coal has a heavier isotope composition (δ¹³C = -24 ‰). The carbon isotope composition of dust particles sampled from the snowpack in different locations in Tomsk showed deviations from the δ¹³С = -28.8 ‰ to δ¹³С = -21.9 ‰.

The definition of the concept “ carbon black” in accordance with modern world ideas was given. The structure of carbon black, the morphology of its aggregates and elemental composition were described in detail. The place of carbon black among other black emissions in the atmosphere was characterized according to international standards; the fundamental differences between carbon black and soot were shown. The sources of carbon black emission into the atmosphere and soil were given. Industrial methods of carbon black production - thermal, furnace and channel - were reported. Basic diagrams of setups for the recovery of carbon black from aerosol streams in the production process providing a maximum possible efficiency of effluent gas and wastewater purification were described. Schemes and principles of operation of the main elements of carbon black recovery systems - cyclones and filters - were presented. The detrimental effects exerted by carbon black on the environment as a whole and on the human body in particular were demonstrated and the maximum permissible concentrations of carbon black were listed. The behaviour of carbon black in the atmosphere and oil contaminated soils was described. Methods of carbon black conversion in the atmosphere and schemes of its oxidation were outlined. A series of model experiments was performed to reveal the effect of carbon black on oil contaminated soils. The beneficial effect of carbon black on the removal of oil contaminants from soils was established. It was shown that carbon black is able to catalyze the destruction of various organic compounds, particularly oil hydrocarbons, thus improving soil fertility. Aerobic deterioration of carbon black in soils with time was discussed.

The results of conjugated studies of contaminations of snowpack and atmosphere air by polyaromatic hydrocarbons (PAH) and soot in a number of major cities of the south of West Siberia are presented. Snow samples selected at the stationary observation stations were analyzed by the method of gas chromatography mass spectrometry (GC-MS) on the content of PAH. The results obtained were compared with the data of the Federal Service for Hydrometeorology and Environmental Monitoring of Russia (Roshydromet) on soot and benzo(a)pyrene in air. Linear correlations between concentrations of considered impurities in conjugated environments were established. The data of ground monitoring snowpack contamination by PAH were compared with the results of winter space image processing by tones of the grey colour.

The results of field studies, chemical-analytical and numerical investigations of snowpack contamination in the winter season of 2014/2015 in the vicinity of Sovetskoye highway of Novosibirsk after its reconstruction of 2009-2014 years. It was shown that substantial reductions of PAH emissions and the change of the space structure of the field of their fallouts, in comparison with the monitoring data of 2008 were shown. Linear correlations between the precipitation content and that of organic and inorganic components of the samples were established. In the kinematic approximation, the few-parametric model of the field reconstruction of precipitations of the polydisperse impurity from the linear source and the method of its numerical realization in the explicit form was proposed. The approbation of the proposed model on the experimental data obtained was carried out.

The decomposition of methane hydrates in coal seams can be one of the causes of the origination of sudden emissions of coal and gas (coal outburst). The formation possibility of methane hydrate in the inner space of natural coal of several types was experimentally studied in the work. Experimental P-T diagrams for a closed system containing wet coal and free methane, demonstrate the peak methane emission into the gas phase when intersecting the curve of the equilibrium of gas hydrates. Less than half of water, sorbed by coal is involved in the formation of gas hydrates. It was shown for the first time that with the degree decrease of metamorphism of coal, the amount of water that is absorbed by natural coal is increased, however herewith; a proportion of water involved in the formation of methane hydrate is decreased.

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.