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991.
992.
S.X. Zeng X.H. MengR.C. Zeng C.M. TamVivian W.Y. Tam T. Jin 《Journal of Cleaner Production》2011,19(13):1426-1437
Small- and medium-sized enterprises (SMEs) form the core of societal and economic development. However, most people query on the implementation and performance of environmental management. In this paper, the manufacturing SMEs in Northern China with different pollution levels are studied to explore the main forces (e.g., government, society, market, and enterprise itself) driving SMEs for promoting environmental management. It focuses on the correlation between environmental management and economic performance for SMEs at different pollution levels. The results show that SMEs of different pollution levels have significant differences in the relationship of driving forces and performance. First, for SMEs with high-pollution levels, social and market driving forces and government incentives are revealed having a significant effect on their environmental performance. Driving forces from within the enterprise itself and the market provide a positive effect on the economic performance, while social forces have a negative effect. Second, for SMEs with light pollution, social and market driving forces, and government assistance play a supporting role on corporate environmental performance improvement. It is also found that the driving force of the enterprise itself does not have a significant effect on the environmental performance for SMEs with different pollution levels. In addition, the environmental performance and economic performance for SMEs with high or light-pollution levels are positively correlated. Further, it shows that the environmental performance is moderately correlated with financial indices, but not significantly with the non-financial indices. 相似文献
993.
994.
995.
Effects on mixed microflora to enhance biohydrogen production from corn stover hydrolysate was studied. 相似文献
996.
Bisphenol A (BPA) is a chemical with high production volume and wide applications in many industries. Although BPA is known
as an endocrine disruptor, its toxic mechanisms have not been fully characterized. Due to its structural similarity to thyroid hormones
thyroxine (T4) and triiodothyronine (T3), one possible mechanism of BPA toxicity is disruption of hormone transport by competitive
binding with the transport proteins. In this study, the binding interactions of BPA, T4, and T3 with three thyroid hormone transport
proteins, human serum albumin (HSA), transthyretin (TTR), and thyroxine-binding globulin (TBG) were investigated by fluorescence
measurement. Using two site-specific fluorescence probes dansylamide and dansyl-L-proline, the binding constants of BPA with HSA
at drug site I and site II were determined as 2.90 104 and 3.14 104 L/mol, respectively. By monitoring the intrinsic fluorescence
of tryptophan, a binding constant of 4.70 103 L/mol was obtained. Similarly, by employing 8-anilino-1-naphthalenesulfonic acid as
fluorescence probe, the binding a nity of BPA with TTR and TBG was measured to be 3.10 105 and 5.90 105 L/mol, respectively.
In general, BPA showed lower binding a nity with the proteins than T3 did, and even lower a nity than T4. Using these binding
constants, the amount of BPA which would bind to the transport proteins in human plasma was estimated. These results suggest that
the concentrations of BPA commonly found in human plasma are probably not high enough to interfere with T4 transport. 相似文献
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998.
变频脉冲电磁装置是物理水处理技术的最新一代产品,它不仅从根本上解决了防垢、除垢难题,而且在杀菌、灭藻、除锈和防腐蚀方面也具有较好的处理效果。 相似文献
999.
Lihui Zhang Guomin Cao Yulei Fei Hong Ding Mei Sheng Yongdi Liu 《Frontiers of Environmental Science & Engineering in China》2011,5(4):604-609
A composite membrane bioreactor (CMBR) integrating the immobilized cell technique and the membrane separation technology was
developed for groundwater denitrification. The CMBR had two well mixed compartments with one filled with the nitrate-containing
influent and the other with a dilute ethanol solution; the compartments were separated by the composite membrane consisting
of a microporous membrane facing the influent and an immobilized cell membrane facing the ethanol solution. Nitrate and ethanol
molecules diffused from the respective compartments into the immobilized cell membrane where nitrate was reduced to gaseous
nitrogen by the denitrifying bacteria present there with ethanol as the carbon source. The microporous membrane was attached
to one side of the immobilized cell membrane for retention of the disaggregated bacteria. Relative to the single dose of external
ethanol, the two-dose supplementation produced better treatment results as evidenced by the lower concentrations of NO3−-N and ethanol (as measured by total organic carbon) of the effluent. The batch treatment in CMBR removed most of the nitrate
in the influent and attained a stable denitrification rate of 0.1 g·m−2·h−1 for most of the 96-h cycles during the 30-cycle study. The effluent was essentially free of ethanol and nitrite nitrogen. 相似文献
1000.
本文全面总结了安庆台山洞的现状,客观指出安庆台山洞巳经不能满足现实需求,并依据地震监测规范要求,就如何改善和解决观测条件和观测系统等方面存在的问题,以实现山洞的再利用进行了深入研究和探讨,认为安庆台山洞可以通过观测环境的改造、观测系统的升级等措施实现山洞再利用,并能够重新发挥安庆台洞体观测在全省地震监测中的重要作用,同... 相似文献