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281.
Soil acidification is one of the rising land degradation issues facing world agriculture. The risk of acidification is currently being assessed as part of agriculture productivity and sustainable theme. This study was conducted to produce a new vermicomposting cast as a recycling resource derived from municipal sewage sludge and waste oyster shell. The earthworm, Eisenia Andrei, was fed under different conditions. The most suitable mixture was 77:23 w/w% of sewage sludge and waste oyster shell. Powdered oyster shell (POS) sludge blend provided a stable pH, due to its buffering capacity during vermiculture because of the Ca2+ and OH? release effect. The vermicast products fulfilled the cast standards of Korea Ministry of Environment for all the parameters such as moisture content, pH, salinity, organic carbon, TKN, Phosphate, and heavy metals. Slowly released organic matter when added to soil improves the capacity of the soil to hold nutrients for plants, improve soil aeration for roots, and improves soil drainage. This product will be an addition to already-commercialized sludge vermicast as a higher value product. 相似文献
282.
Climate change has recently become a major focus for industry and government agencies. Some recent works have been reported on the use of pinch analysis techniques for carbon-constrained energy planning problems. This paper discusses a new application of graphical technique based on pinch analysis for company-level visualization and analysis of carbon footprint improvement. The technique is based on the decomposition of total carbon footprint into material- and energy-based components, or alternatively, into internal and external components. The decomposition facilitates the evaluation and screening of process improvement alternatives. Two industrial case studies on the production of phytochemical extracts and bulk chemicals are used to illustrate the new extension. 相似文献
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Y. Henmi 《Marine Biology》1989,101(1):53-60
Two behaviorally distinct forms — courtship signal — (Form L and V) of Macrophthalmus japonicus (De Haan) are known. Monthly samples of each form were collected from two areas in Japan: Form L from Amakusa, western Kyushu, between April 1985 and February 1986; Form V from Fukuoka, northern Kyushu, between November 1982 and December 1983. Life-history traits were compared between two populations and discussed. Individuals from the Amakusa population grew more slowly and matured at a smaller size than those from the Fukuoka population. Maturation period and longevity did not differ significantly. In the first year of reproduction, females in the Fukuoka population produced more, and larger broods than those in the Amakusa population and crab mortality was higher in every age group. Egg size did not differ significantly. The major environmental factors — air-temperature, nitrogen content of the surface mud and period of aerial exposure were similar in both areas, and it is suggested that the differences in life-history exhibited by these crabs are genotypic, and perhaps related to their different form. 相似文献