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81.
The health of cultivated blue mussels from an offshore and a nearshore sites was compared by assessing lysosomal membrane stability (LMS) and accumulations of lipofuscin and neutral lipids in the digestive glands. In addition, the condition index, parasite infestation rates, growth performance and energy status of the mussels were assessed during 10?months of sampling. Abiotic and biotic site characteristics were investigated by water analysis for each sampling cycle. Further, data of contaminant loads of the softbody and pollutant concentration of the water column, suspended particles and sediments from both sites were analysed. Results show that positive offshore effects due to dilution of contamination were not evident for all parameters analysed. Condition indices were high, and parasites were not present in offshore mussels. In contrast, the integrative health parameter LMS and growth performance were slightly, but not significantly, better in the nearshore cultivated mussels. These findings correspond with the higher contaminant concentrations in the softbodies of mussels and the water column from the offshore testing site. Both sites showed low LMS values and high accumulations of lipofuscin and neutral lipids, indicating that environmental conditions in the German Bight are generating stress for blue mussels even in the offshore areas. Exposure to fluvial transport points to a comparable probability for high contamination loads similar to nearshore areas. We therefore recommend adding a minimum salinity threshold to the definition of offshore aquaculture to exclude areas under fluvial influence.  相似文献   
82.
The lowland and coastal regions are the areas where cotton is cultivated in Yemen. The land used for this purpose exceeds 120 acres and expandable in the upcoming seasons. We have selected the earlier two varieties of cotton fibers cultivated in two different areas Abyan and Zabid. Wide Angle X-ray Scattering (WAXS) data from these fibers have been recorded and analysed to obtain the micro-structural parameters with the application of Line Profile Analysis (LPA). Linked Atom Least Squares (LALS) program has been used to obtain molecular structure and packing in these fibers. For the first time micro-structural parameters of these cotton fibers cultivated in Yemen are computed and reported. This study will be of help to understand the structure-property relation in these cotton fibers.  相似文献   
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Eurasian Soil Science - We studied the state of the soil cover in sanitary protection zones of two large oil refineries in Samara region (at distances up to 1000 m from the refineries) using a...  相似文献   
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The effect of humic acids (HAs) on physiological processes (photosynthesis, respiration, and abundance) of green microalga Chlorella vulgaris has been studied, and the relationships between the physiological activity of HAs and their structural parameters have been investigated. It has been found that the optimum range of HA concentrations for the growth of C. vulgaris is 0.01–0.03%. In this range, the highest positive effect on total photosynthesis increment is due to hydrophilic HA preparations from fallow soddypodzolic soil (Albic Retisol) and virgin gray soil (Luvic Greyzemic Phaeozem). The minimum stimulation of respiration is noted for all HA preparations in the region of the maximum photosynthesis stimulation. At concentrations above 0.003%, all HA preparations have a negative effect: the rate of photosynthesis in C. vulgaris cells decreases, and their respiration is strongly enhanced. The abundance of C. vulgaris under the effect of all of the studied preparations under illumination increases more rapidly than in the dark. A high positive coefficient of correlation is found between the hydrophilicity of HAs calculated from 13C NMR data and the photosynthesis rate in C. vulgaris.  相似文献   
89.
It is known that brass is the construction material widely used when manufacturing agricultural equipment. An effective volatile inhibitor is offered to protect it from corrosion in the atmosphere of the livestock premises with 100% and close to it relative humidity of the air containing the stimulators of this process—CO2, NH3, H2S—in the concentrations that multiply exceed the background ones. A range of methods—weight corrosion tests and electrochemical measurements (potentiodynamic polarization, polarization resistance, fixed in the automatic mode)—define the conditions under which the inhibitors of the IFKHAN series multiply slow down the corrosion of brass. The general corrosion rate of L62 brass is decreased ten times in the presence of all studied inhibitors of this series in the atmosphere containing up to 20 mg/m3 of H2S and 100% relative humidity. It is most reasonable to use the IFKHAN-112 inhibitor with the ammonia content up to 30 mg/m3 in the maximum humid atmosphere.  相似文献   
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