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Environmental Science and Pollution Research - Massive discharge of wastes produced by the processing of leather so far confers the most important environmental challenge facing the tanneries...  相似文献   
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ABSTRACT: Nutrient fluxes in precipitation, throughfall, and stemflow were studied in an oak-hickory forest in southern Illinois for a three-year period beginning in 1973. Nutrient inputs in these water related pathways were approximately one-half those of litterfall; a major nutrient return mechanism. Considering these water carried nutrients (116 kg/ha/yr), 38% was contributed by precipitation, 35% by throughfall and approximately 27% by stemflow. Although the total nutrient input is only one-half that of litterfall, the net impact on short-term nutrient requirements is considerable because of their immediate availability. Nutrient inputs in litter represent a delayed return mechanism because of the relatively slow decomposition process.  相似文献   
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ABSTRACT: Several predictors for the maximum local scour around cylindrical objects are compared to available experimental data. The range of flow parameters for which these formulas are valid are presented. The best predictors among those compared in this study were identified. Based on the available data a formula for estimating local scour around cylindrical objects is also given.  相似文献   
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Mechanical pulping process is electrical energy intensive and results in low paper strength. Biomechanical pulping, defined as the fungal treatment of lignocellulosic materials prior to mechanical pulping, has shown at least 30% savings in electrical energy consumption, and significant improvements in paper strength properties compared to the control at a laboratory scale. In an effort to scale-up biomechanical pulping to an industrial level, 50 tons of spruce wood chips were inoculated with the best biopulping fungus in a continuous operation and stored in the form of an outdoor chip pile for 2 weeks. The pile was ventilated with conditioned air to maintain the optimum growth temperature and moisture throughout the pile. The control and fungus-treated chips were refined through a thermomechanical pulp mill (TMP) producing lightweight coated paper. The fungal pretreatment saved 33% electrical energy and improved paper strength properties significantly compared to the control. Since biofibers were stronger than the conventional TMP fibers, we were able to reduce the amount of bleached softwood kraft pulp by at least 5% in the final product. Fungal pretreatment reduced brightness, but brightness was restored to the level of bleached control with 60% more hydrogen peroxide. The economics of biomechanical pulping look attractive.  相似文献   
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Environmental Science and Pollution Research - Climate change is severely damaging the agricultural system of many food producing regions worldwide. Small/subsistent livestock herders are the most...  相似文献   
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Environmental Science and Pollution Research - Groundwater resources are highly stressed due to their overuse, especially in the arid region. This study is aimed at discovering potential...  相似文献   
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Environmental Science and Pollution Research - Diabetes is a global health concern that has affected almost 415 million people globally. Bromocriptine is a dopamine D2 agonist, which is a Food and...  相似文献   
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Environmental Science and Pollution Research - Macroinvertebrate community in the intertidal setup plays an important role in coastal ecosystem functions and biogeochemical cycle. However,...  相似文献   
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Laser cutting of alumina tiles is carried out, and the temperature and stress fields developed in the cutting section are predicted numerically using ABAQUS finite element code. The morphological changes along the cut edge surfaces are examined using the optical and scanning electron microscopes. The residual stress formed in the cutting section is obtained after incorporating the XRD technique. The residual stress predicted is compared with the experimental data. It is found that the residual stress predicted agrees well with the experimental results. The dross attachment at the kerf exit is observed, which is associated with the high melting temperature of the workpiece.  相似文献   
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