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161.
The influence of anthropogenic loading on the distribution of soft bottom benthic organisms of a tropical estuary (Cochin backwaters) was examined. The industrial activities were found to be high in the northern and central part of the estuary, where dissolved inorganic nitrogen (DIN > 210 ??M) and phosphorus (DIP > 6.5 ??M) have caused high abundance of chlorophyll a (up to 73 mg m???3) and accumulation of organic carbon in sediments (up to 5%). Principal component analysis distinguished three zones in the estuary. The central zone (Z1) was characterized by organic enrichment, low species diversity, and increased number of pollution tolerant species. Long-term deterioration of the estuary is indicated by an increase in the nutrients and chlorophyll a levels by sixfold during the last few decades. Flow restrictions in the lower estuary have lead to a fourfold increase in sediment organic carbon over the period of three decades. The reduced benthic diversity followed by an invasion of opportunistic polychaetes (Capitella capitata), are indicative of a stress in the estuary.  相似文献   
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The development of cladding through microwave radiation is recently explored and very few, initial studies were reported elsewhere. In order to explore more viability of process, (EWAC (Ni based) + 20% Cr23C6 powder) composite cladding has been developed on substrate austenitic stainless steel (SS-316). The experiments were conducted in domestic microwave oven and the clad of thickness, approximate 500 m has been developed by the exposure of microwave radiation at frequency 2.45 GHz for duration of 360 s. Typical clads cross sections of composite clads showed good metallurgical bonding with the substrate by partial dilution. The back scattered electron image of clad cross section showed the reinforced chromium carbide (Cr23C6) particles are uniformly distributed and well embedded in the Ni based matrix. The developed clad is free from visible solidification cracking and has significantly less porosity which is of the order of 0.90%. The XRD pattern of the developed clad showed the presence of FeNi3, NiSi and Cr23C6 phases. The average Vicker's microhardness of developed clad was observed as 425 ± 140 Hv.  相似文献   
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Environmental Science and Pollution Research - Recent advancements and growing attention about free radicals (ROS) and redox signaling enable the scientific fraternity to consider their involvement...  相似文献   
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Environmental Science and Pollution Research - Mining and extraction of stones and minerals play a significant role in many countries economic growth in the world. The production of dolomite...  相似文献   
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Environmental Science and Pollution Research - Diabetes is one of the most comprehensive metabolic disorders and is spread across the globe. The data from IDF Diabetes Atlas and National Diabetes...  相似文献   
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Environmental Science and Pollution Research - Inevitably increase in plastic demand has resulted in an overgrowing production on a global scale. The utilization of plastics has been applied to a...  相似文献   
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The Science of Nature - Leaf-cutting ants are highly successful herbivores in the Neotropics. They forage large amounts of fresh plant material to nourish a symbiotic fungus that sustains the...  相似文献   
170.
Male albino rats were administered Cd and HCH daily for six weeks to study the effect of Cd on storage and metabolism of HCH. The results indicated a marked inhibition of the metabolism of HCH in the group dosed with HCH + Cd. The metabolic rate of HCH in the group dosed with HCH + Cd was also significantly lower than that in the group dosed with HCH alone. The hepatic content of Cd and Zn was significantly increased whereas a marked depletion of Cu and Fe was observed in the groups exposed to Cd and HCH + Cd. A high level of free Cd and Zn or a low level of Fe and Cu in liver seemed to play an important role in the metabolic inhibition observed in this study.  相似文献   
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