Home – Home – Jornals – Atmospheric and Oceanic Optics 2020 number 6

The chemical composition (ions, elements, polycyclic aromatic hydrocarbons) of atmospheric aerosol in the North Atlantic, in the European and Russian parts of the Arctic Ocean and in the seas of the northern latitudes and the Far East was analyzed. The studies were carried out on board the research vessels along their cruise routes (RV “Akademik Treshnikov", RV “Akademik Mstislav Keldysh", RV “Professor Multanovsky"). The air was sampled using the methodology accepted by the international networks operating under the Acid Deposition Monitoring Network in East Asia (EANET) and European Monitoring and Evaluation Programme (EMEP). The analysis of the chemical composition of the aerosol along the routes of the research cruises showed the following below. The total ion content and the concentrations of individual ions in the aerosol of the North Atlantic and in the European part of the Arctic Ocean correspond to the data that was obtained within the measurement work fulfilled in the Laptev and Kara Seas in 2018 and 2019. The increased values of the sum of PAHs in Russia's central regions in the Arctic correspond quite well to the increased concentrations of ions and trace elements in the content of the aerosol. Trace elements are noted to have different concentrations in the content of the aerosols of the North Atlantic and Russia's central regions of the Arctic. This fact can point at different sources of these components.

As a result of microbiological research, information on the number and diversity of psychrotolerant yeast isolated from high-altitude and ground-based samples of atmospheric aerosol in the south of Western Siberia were obtained. In certain phenotypic and genomic characteristics, the yeast isolates were referred to the genera Saccharomyces , Candida , Sporidiobolus , Aureobasidium , Sporobolomyces , Cryptococcus , Rhodotorula , and other. Both saprophytic and pathogenic microorganisms were detected. The strain of yeasts of the genus Aureobasidium actively producing exopolysaccharides and melanin and being perspective for biotechnological developments were revealed.

Field measurements of the concentrations of oxygenated organics in urban air and in forest were carried out. The results were used to test the model of atmospheric transformation of biogenic compounds. The simulation showed that condensable compounds of several classes are formed: hydroperoxides, peroxides, alkylperoxynitrates and nitrites, peracids. Their aerosol-generating potential was evaluated on the basis of the calculated steady-state concentrations of the direct precursors of aerosol phase. It was discovered that the main precursors of the nuclei of solid phase are hydroperoxides and peracids. The reason of their efficiency is their photolysis with the formation of oxygenated free radicals, which initiate gas-to-particle conversion through polymerization of unsaturated compounds via the free radical mechanism.

The regional correction of the EMEP inventory data (European Monitoring and Evaluation Program) is one of the ways to improve the accuracy of model calculations of pollutant concentrations based on chemical transport models (CTM). Methods for correcting original EMEP emissions are proposed and described. On the example of CTM CHIMERE calculations for the Moscow region, the effectiveness of the application of the emission correction procedure is shown, which is confirmed by a decrease in the errors of model calculations of the PM₁₀ concentration. The completed regional developments for the correction of emissions can be used for other regions of Russia.

The article presents the assessment result of the pyrogenic factor contribution to atmospheric pollution in the background territories of the Tomsk region based on the analysis of heavy metal (Zn, Pb, Cu, and Cd) atmospheric deposition within the Bakchar bog (the north-eastern part of the Great Vasyugan mire). The analysis of atmospheric depositions of Cu, Pb, Zn, and Cd was carried out using the method of passive dust deposition by the content of particles per 1 m² during 2018-2019. Data analysis showed an excess of Zn in atmospheric depositions that persists for three years after a fire in a drained mire during both summer and winter observation periods with a maximum value of 3.63 mg/m² per month in 2018. The impact of the fire on Cd and Pb content was maintained for two years after the fire. The Cu content in atmospheric depositions is not affected by the pyrogenic factor. The analysis of seasonal dynamics showed that the content of Zn, Cd, and Pb in the composition of atmospheric depositions was influenced by wild fires that cause the transfer of pollutants both on the local and regional scales.

The comparative analysis of chemical composition of water- and acid-soluble fractions of aerosols, collected in autumn, winter, and spring by passive sampling is performed. Statistical data manipulation is carried out, coefficient of aerosols’ accumulation and absolute amount of aerosol enrichment are calculated. Seasonal changes in the chemical composition of aerosol fractions are revealed, furthermore, tracer elements of heat-power industry.

Technique for generation of cefazolin aerosol particles with the size from 80 to 1400 nm is described. Experiments with aerosol drug administration on laboratory animals (mice) showed the efficiency of this cefazolin delivery technique to be close to the efficiency of intravenous injection.

The earlier proposed hypothesis (Zuev et al., 2014) about the possibility of nanodispersed black carbon particles formation in eruptive column of volcanic eruption with VEI ³ 4 is discussed. The probable characteristics of volcanogenic soot particles and their distinctive features from stratospheric black carbon particles of other origin are analyzed. A brief review of suitable instrumental methods for detecting particles is carried out, and observational facts that indicate the possible detection of particles of volcanic soot earlier are presented. The idea of a complex experiment for observational confirmation of the hypothesis is proposed.

A method for determining the ion of height of rise of smoke plumes from pipes of industrial enterprises from using satellite information is suggested. It is tested on the example of the thermal power station in Novosibirsk. The results are compared with the results of calculations according to conventional methods. Possibilities of application of this approach to different meteorological conditions and characteristics of underlying surface are discussed.

Stationary motion of a large non-volatile spherical aerosol particle, inside which heat sources operate, under the effect of the gradients of temperature and binary gas mixture component concentrations in the external field is described in the Stokes approximation. The average surface temperature of the particle is assumed to significantly differ from the temperature of the surrounding binary gas mixture. The gas dynamics equations are solved with power temperature dependences of the coefficients of viscosity, thermal conductivity, diffusion, and density of the gaseous medium. Diffusive and thermal sliding motions are taken into account in the boundary conditions. Numerical estimates have shown that the photo-thermal and diffusiophoretic force and velocity significantly depend on the average temperature of the particle surface.

Adsorption and photocatalytic properties of precipitated indic oxide aerosol particles are studied under ambient air conditions. The composition analysis of the adsorbed layer of aerosol particles is carried out. The quantum yields and its spectral dependences of oxygen photoadsorption and carbon monoxide photocatalytic oxidation are determined. Photocatalytic activity of carbon monoxide oxidation is detected during the absorption of light quanta from the region of indirect electron transitions (quantum energy < 2.9 eV).

Sedimentation of the pollen particulates of goat willow, bay willow, asian black birch, hoary plantain, white goosefoot, and sieversian wormwood is studied. It is shown that the dispersion of the pollen of these six species provides a considerable number of clusters of two or more grains, composing from 32.4 to 53.3% of the resulting particles. These clusters contain from 59.4 to 79.2% of the pollen dispersed. The sedimentation rate of the clusters, including from 1 to 6 pollen grains, is estimated. The dependence of the agglomerate sedimentation rate on the number of the pollen grains included is derived. The impossibility of formation of similar clusters on impactor substrates when spraying pollen is shown.

Analysis of vegetation dynamics of the Myldzhinsky oil-producing territory in the Tomsk region using time series of satellite data is performed. All estimates are based on annual time series of Moderate Resolution Imaging Spectroradiometer (MODIS) imagery for growing season from 2015 to 2019. By means of geoinformation system ArcGis, circular zones around the Myldzhinskoye field with radii of 10, 20, 30, and 40 km were built. Average values of the Enhanced Vegetation Index (EVI) were calculated for each of the constructed zones. Analysis of the results showed specific seasonal cyclicity of EVI, in the “inner" zone (10 km diameter) of Myldzhinsky field, which manifests itself in the reduction of the growing season plant communities.

The results of an experimental study of dynamics of the formation of liquid-drop aerosol cloud during the destruction of a spherical liquid core with an initial volume of 2-80 ml during its gravitational sedimentation are presented. The system of similitude criteria which determines the dynamics of the destruction of a liquid macro-volume with the formation of a polydisperse liquid-drop aerosol cloud was derived by the Rayleigh method. It is shown that the prevailing mechanism of the decay of the liquid macro-volume is the development of Rayleigh-Taylor instability when the critical value of the Bond number is reached. A criterion equation is derived for determining the distance passed by a liquid macro-volume to its complete destruction from the Bond number characterizing the influence of surface tension forces. The maximum droplet size in the aerosol cloud was estimated depending on the critical value of the Weber number.