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21.
Doklady Earth Sciences - The data obtained for 2015–2017 on the content and composition of aliphatic hydrocarbons (HCs) in particulate matter at the river–sea geochemical barriers (the... 相似文献
22.
Oceanology - The results on the content, composition, and distribution of chloroform bitumoids (CBs) in the Holocene sediments of the Barents Sea are presented (Cruise 68 of the R/V Akademik... 相似文献
23.
Organic compounds in the snow-ice cover of eastern Antarctica 总被引：2，自引：0，他引：2
I. A. Nemirovskaya 《Geochemistry International》2006,44(8):825-834
This paper presents data on the concentration and composition of organic substances, lipids, and hydrocarbons, in the snow-ice
cover of fast ices and continental lakes of Antarctica. It was shown that organic compounds were accumulated in the layers
with the most intense autochthonous processes (mainly at the snow-ice and ice-water boundaries). These zones remain active
at a biogeochemical medium even at low temperatures. The maximum content of organic compounds (10–20 times that of the snow-ice
cover of other regions) and a sharp change in the proportions of their migration forms in the ice volume were detected in
the regions of penguin colonies (fast ice at Buromsky Island and a lake in Haswell Island). The content and composition of
hydrocarbons in Antarctic ices were compared with those of Arctic ices.
Original Russian Text ? I.A. Nemirovskaya, 2006, published in Geokhimiya, 2006, No. 8, pp. 891–901. 相似文献
24.
The White Sea is a natural analogue of arctic seas. The pollution of the sea by petroleum hydrocarbons is not high now. However,
the load on sea ecosystem can increase in the nearest future because of the anticipated industrial development in its watershed,
including an increase in oil, coal, and diamond production. The specific features of the nature of arctic marine systems (hydrological,
ice, hydrobiological, hydrochemical, and radiation regimes), and the poor knowledge of the conditions of dispersion, transformation,
and utilization of petroleum hydrocarbons in such seas make their ecological studies especially important. Petroleum hydrocarbon
concentrations in the waters of tributaries and water areas of the White Sea (for 1980–2006 and 1989–2006, respectively) were
evaluated using literary and authors’ data. Analysis of the collected materials shows that the majority of petroleum hydrocarbons
enter the sea’s water areas with river runoff. Petroleum hydrocarbon concentrations were evaluated in major tributaries of
the sea, including the rivers of Northern Dvina, Onega, Mezen, Niva, Kem, and Keret, delivering petroleum hydrocarbons into
the bays of Dvina, Onega, Mezen, and Kandalaksha, water area near the Solovetskie Islands, and Chupa Bay, respectively (Bay
— Gulf). Model calculations should yield within-year variations in petroleum hydrocarbon concentrations in different part
of the sea (under a correctly specified load) and the conditions of their biotransformation and horizontal transport through
the boundaries between areas within the sea. 相似文献
25.
Data are presented on the content of hydrocarbons (HC) relative to the concentrations of particulate matter, lipids, Corg, and chlorophyll a in the surface waters and snow-ice cover of the East Antarctic coastal areas. It was shown that the growth of the concentrations
of aliphatic HC (AHC) to 30 μg/l in the surface waters takes place in the frontal zones and under the young ice formation.
The AHC content in the snow increases with the growth of the aerosol content in the atmosphere. In the lower part of the ice
at the boundary with the seawater, despite the low temperatures, the autochthonous processes may provide high AHC concentrations
(up to 289 μg/l). Within the snow-ice cover on fast ice, synchronous content variations of all the compounds considered take
place. 相似文献
26.
Water Resources - The concentrations of heavy metals in gray silts were analyzed in the Volga cascade of Reservoirs (June 2016, R/V Akademik Topchiev, Borok Village–Astrakhan City). The mean... 相似文献
27.
Oceanology - The article presents the first data on the content of organic compounds (OCs): Corg, lipids, and hydrocarbons (aliphatic—AHCs) and polycyclic aromatic (PAHs)) in suspended... 相似文献
28.
In the Antarctic zone, integrated studies of particulate matter in surface waters and the snow-ice cover were carried out
by means of geochemical (the concentrations of particulate matter, Corg, hydrocarbons, lipids, and chlorophyll a) and optical techniques. Correlations between the treated compounds were found. A regression equation was created that enabled
us to evaluate immediately the amount of particulate matter using the parameter of light attenuation by seawater. New data
were obtained for the processes of accumulation of particulate matter and organic compounds under ice formation. 相似文献
29.
S. M. Zhmodik Yu. A. Kalinin N. A. Roslyakov A. G. Mironov Yu. L. Mikhlin D. K. Belyanin N. A. Nemirovskaya A. M. Spiridonov G. V. Nesterenko E. V. Airiyants T. N. Moroz T. A. Bul’bak 《Geology of Ore Deposits》2012,54(2):141-154
Formation of noble metal nanoparticles is related to various geological processes in the supergene zone. Dispersed mineral phases appear during weathering of rocks with active participation of microorganisms, formation of soil, in aqueous medium and atmosphere. Invisible gold and other noble metals are incorporated into oxides, hydroxides, and sulfides, as well as in dispersed organic and inorganic carbonic matter. Sulfide minerals that occur in bedrocks and ores unaltered by exogenic processes and in cementation zone are among the main concentrators of noble metal nanoparticles. The ability of gold particles to disaggregate is well-known and creates problems in technological and analytical practice. When Au and PGE nanoparticles and clusters occur, these problems are augmented because of their unusual reactions and physicochemical properties. The studied gold, magnetite, titanomagnetite and pyrite microspherules from cementation zone and clay minerals of laterites in Republic of Guinea widen the knowledge of their abundance and inferred formation conditions, in particular, in the contemporary supergene zone. Morphology and composition of micrometer-sized Au mineral spherules were studied with SEM and laser microprobe. The newly formed segregations of secondary gold on the surface of its residual grains were also an object of investigation. The character of such overgrowths is the most indicative for nanoparticles. The newly formed Au particles provide evidence for redistribution of ultradispersed gold during weathering. There are serious prerequisites to state that microorganisms substantially control unusual nano-sized microspherical morphology of gold particles in the supergene zone. This is supported by experiments indicating active absorption of gold by microorganisms and direct evidence for participation of Ralstonia metallidurans bacteria in the formation of peculiar corroded bacteriomorphic surface of gold grains. In addition, the areas enriched in carbon and nitrogen have been detected with SEM on the surface of gold spherules from Guinea. Such organic compounds as serine, alanine, and glycine are identified on their surface with Raman spectroscopy. The experiments have been carried out and new data have been obtained indicating the role of micromycetes in concentration and distribution of noble metals in ferromanganese nodules of the World Ocean. Au and Pt were detected in the system with radioisotopes. It has been established that two forms of gold distribution develop within pseudomorphs of fungi colonies: (1) as pseudomorphic concentrates and (2) dispersed form unrelated to the colony structure. Inhomogeneities in distribution of dispersed platinum are manifested in the form of linear anomalies with elevated concentrations at the margins of the colonies. 相似文献
30.