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The results of studies with the use of bioassaying methods for evaluating the efficiency of wastewater treatment processes and their effect on the biological adequacy of the natural aquatic environment are given. It is stressed that a test for wastewater toxicity with the use of most informative bioassaying methods should be included in the regulatory requirements.  相似文献   
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Measurements of formaldehyde (HCHO) were made at the Cape Verde Atmospheric Observatory between November 2006 and June 2007 using the Long-Path Differential Optical Absorption Spectroscopy (LP-DOAS) technique. Observations show that typical HCHO mixing ratios ranged between 350 and 550 pptv (with typical 2-σ uncertainties of ~110 pptv), with several events of high HCHO, the maximum being 1,885?±?149 pptv. The observations indicate a lack of strong seasonal or diurnal variations, within the uncertainty of the measurements. A box model is employed to test whether the observations can be explained using known hydrocarbon photochemistry; the model replicates well the typical diurnal profile and monthly mean values. The model results indicate that on average 20% of HO2 production and 10% of OH destruction can be attributed to the mean HCHO levels, suggesting that even at these low average mixing ratios HCHO plays an important role in determining the HOx (HO2+OH) balance of the remote marine boundary layer.  相似文献   
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The influence of temperature on rock samples of the Bazhenov Formation is shown. The samples underwent pyrolysis at 300–480°C, as well as in closed autoclaves in the presence of water under formation pressure. The temperature impact at 400°C resulted in a decrease in the S2 pyrolytic peak by 90–95% and almost complete formation of the generation potential of the rocks. Microtomographic studies of samples combined with raster electron microscopy revealed a correlation between the variable reservoir properties of the rocks. At 350°C, the rocks are characterized by a system of fractures; as a result of impacts, the porosity and permeability can increase from several to several tens of times. Our results will allow more precise modeling of the influence of tertiary processes on the rocks of the Bazhenov Formation in order to increase the final oil recovery of the bed.  相似文献   
36.
Spectral observations of the Herbig Ae star MWC 480 are reported. Observations were made on the 2.6 m telescope at the Crimean Astrophysical Observatory and the 6 m telescope at the Special Astrophysical Observatory in the neighborhoods of the sodium resonance doublet, the He I 5876 line, the oxygen O I 7774 line, the H line, and some others. The H line has a P Cyg-type profile which is typical of anisotropic decelerated material outflows. The parameters of the line profile vary on a time scale on the order of days or longer. The blue wing of the line profile, in which noticeable changes are detectable over times of a few hours, is subject to the greatest variation. An unusual line shape is observed in the sodium lines. Their profiles resemble type P Cyg profiles with discrete absorption components can be seen in the blue wing. The number, shape, and radial velocities of the components change with time. The maximum radial velocity is -330 km/s and the minimum, about -50 km/s. The high velocity components are subject to the greatest variability. An analysis of the spectral variability yields the following conclusions: (1) the inner layers of the accretion disk of MWC 480 reach right to the star. The maximum rotation velocity of the circumstellar gas derived from the oxygen OI 7774 line shape is close to 400-500 km/s, which corresponds roughly to the radius of the last Keplerian orbit. (2) A highly nonuniform, high velocity component of the disk wind, which contains dense fragments (microjets), develops in this region. They appear to form as a result of the unstable structure of the magnetic field in the layers of the accretion disk closest to the star. (3) The maximum velocities of the microjets are only slightly higher than the escape velocity at the star's surface. Thus, the bulk of the momentum which they acquire is expended in overcoming the star's gravity and this causes a deceleration in the radial motion of the gas. This kind of structure for the radiating region is consistent with magneto-centrifugal models of the disk wind in which the intrinsic magnetic field of the accretion disk plays a dominant role in the acceleration of the gas.  相似文献   
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The paper discusses new data resulting from petrographic examination of the composition and structure of Cenozoic sediments penetrated by Well 10 to a depth of 2350 m in the Upper Telekai oil-and-gas field within the Anadyr Basin. An alluvial-deltaic sedimentation environment of tuffaceous-sedimentary and terrigenous producing Lower Miocene rocks was found and their secondary alterations examined, including formation of clay minerals, carbonates, and zeolite. The vitrinite reflectance indices allowed determination of the catagenic zoning of the Miocene succession, and a significant catagenic unconformity related to pre-Pliocene erosion was recorded at its top.  相似文献   
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The experimental results on synthetic oil production from rocks of the Domanik Formation under hydrothermal conditions are reported. The potential for oil-product extraction from the oil fractions of the rocks under a hydrothermal impact was up to 60 mg/g or 6.0 wt %. The injection of inorganic additives (sodium carbonate or silica gel) did not increase the oil-recovery factor. As well, the amount of the recoverable oil products directly depended on the mineral composition of the rocks. The relationship between the percentage of hydrocarbon yield and the mineral composition of the rocks was determined. Clay minerals and silica increased the yield of synthetic oil; carbonates, conversely, inhibit the process.  相似文献   
40.
Identification of contaminants, determination of their biological hazard and content in water are important practical tasks while assessing water quality in sources of drinking water supply of large cities. Presented herein is a review regarding pharmaceutical pollution of waters in various countries. Given are original data concerning contamination of water objects—sources of water supply of Moscow with components of pharmaceuticals and metabolites of therapeutic agents. Worked out is a retrieval and calculation technology of assessing hazards of substances. Proposed is the use of “structure-activity” calculation technologies for prediction of side effects of pharmaceuticals and pharmacological activity of other organic xenobiotics not used in medicine. Certain ways of decreasing pharmaceutical pollution are recommended.  相似文献   
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