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151.
微生物燃料电池利用甘薯燃料乙醇废水产电的研究 总被引:3,自引:2,他引:1
利用空气阴极微生物燃料电池(MFC)处理甘薯燃料乙醇废水,以COD为5000mg/L的废水做底物,获得的最大电功率密度为334.1mW/m2,库仑效率(CE)为10.1%,COD去除率为92.2%.实验进一步考察了磷酸缓冲液(PBS)浓度和废水浓度对MFC产电性能的影响.PBS含量从50mmol/L增加到200mmol/L,MFC输出的最大电功率密度提高了33.4%,CE增加26.0%,但PBS对废水的COD去除率影响不大.含50mmol/LPBS的废水COD从625mg/L增加到10000mg/L,COD去除率和MFC输出的最大电功率密度在废水浓度为5000mg/L处均获得最大值,但CE值有降低的趋势,从28.9%变化至10.3%.这些结果表明,MFC可以在处理甘薯燃料乙醇废水的同时获得电能;增大PBS浓度能提高MFC的产电性能;MFC输出的最大电功率密度随废水COD增加而增大,但废水浓度过高会引起酸化使MFC产电性能下降. 相似文献
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153.
微生物燃料电池构造研究进展 总被引:2,自引:0,他引:2
微生物燃料电池(Microbial fuel cell,MFC)的研究在近几年获得了快速发展.产电微生物在厌氧条件下氧化底物释放电子和质子,电子通过导线传递给阴极,从而在外电路中形成电流,而质子通过质子交换膜进入阴极与电子和氧气结合生成水.微生物燃料电池的研究与应用开发涉及到从微生物、电化学到材料学和环境工程等科学领域的交叉,特别是废水处理能与微生物产电相结合的研究成果,使污水、污泥、垃圾等环境污染物的治理有可能成为生物质能源的生产过程,展示了微生物燃料电池的广泛应用前景.本文着重综述微生物燃料电池在构造上的进展,并介绍了其在水处理中的应用前景.图8参56 相似文献
154.
ABSTRACTThis paper provides a theoretical model to explain the causality between China’s energy transition and capital deepening found by the empirical study. We prove that in the equilibrium, China’s energy transition is endogenously determined by capital deepening due to the homogeneity of electricity and the monopolistic competition features of China’s electricity market. Price effect, which is the effect of change in relative factor price, will affect energy transition only if the policy intervenes electricity price in terms of the primary sources from which it is generated. We propose that investment can promote energy transition by stimulating capital deepening which is biased to clean energy development. In this regard, our paper provides a new way of thinking for other developing countries to design an effective energy transition policy. 相似文献
155.
我国《能源发展战略行动计划(2014—2020年)》指出,加快构建清洁、高效、安全、可持续的现代能源体系,重点实施"绿色低碳"等四种能源发展战略,因此"以电代煤"将成为我国未来能源战略中的一项重要选择。本文运用技术经济分析法和排放系数法,计算了八大主要用能部门以电代煤的经济成本和环境价值。计算结果表明:各部门用电设备的初始投资和电力消费等经济成本是燃煤设备的初始投资及燃煤消费等经济成本的1.8~2.8倍,但是,以用电设备替代燃煤设备的环境价值非常可观。在考虑了环境外部性成本后,居民生活行业,商业,非金属矿物制品业,石油加工、炼焦和核燃料加工业,化学原料和化学制品制造业,以及非高耗能工业六个部门进行"以电代煤"在目前的情况下具有经济可行性,而有色金属冶炼和压延工业,以及黑色金属冶炼和压延工业"以电代煤"暂时不具有经济可行性。最后,提出了相关政策建议。 相似文献
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159.
Zeinab Tavasoli Parviz Abdolmaleki Seyed Javad Mowla Faezeh Ghanati Amir Sabet Sarvestani 《The Environmentalist》2009,29(2):220-224
This research was carried out to evaluate the influence of static magnetic field on the rate of apoptosis in bone marrow stem
cells (BMSCs) of rats. Extracted cells were suspended in αMEM as a culture media for 48 h. After that, cells were exposed
to 15 mT static magnetic field (SMF) for 5 h, incessantly with or without FeCl2. The rate of apoptosis was then assessed via flow cytometery. The results showed that either treatment with FeCl2 or exposure to SMF enhanced the rate of apoptotic cells. Moreover, cells that were treated simultaneously with FeCl2 and SMF have higher rate of apoptosis. An increase in apoptosis by 26.5% was induced by SMF alone and an increase in apoptosis
by 28.2% was induced by a combination of FeCl2 and SMF, compared to their corresponding controls. The results recommended that the effects of SMF on apoptosis may be related
to increment of the number of free radicals in the cells. 相似文献
160.
Experimentally induced acute inflammation in rats is a good model system which includes the complexity and dynamics of the
processes; moreover there are many defined markers for following and estimating changes in an observed system. In this paper,
we discuss an in vivo model of acute inflammation induced by carrageenan. Carrageenan-induced paw edema is a model of non-infectious
acute inflammatory reaction to assess the contribution of mediators involved in vascular changes associated with acute inflammation
and potential treatments. A complex approach into the investigation of possible effects of static magnetic fields (SMF) action
on experimentally induced acute inflammation in rats (by measurements of the levels of specific stress markers) is very important
in understanding the possible inflammatory mitigation effects, pain relief, and oxidative stress state of an organism. This
approach could help for better understanding of the possible mechanisms of interaction of dynamic processes such as inflammation
healing and pain relief with external SMF (25 mT at 10, 20 and 30 min exposure time). Results indicate that SMF with B = 25 mT
for 30 min diminished the inflammatory process and decreased the levels of inflammatory markers (fibrinogen) and stress markers
(ACTH, Cor) into the blood plasma in rats as when compared with sham exposed animals. The exact mechanism by which SMF contributes
to the acceleration of inflammatory healing and decrease of inflammation markers in blood plasma in rats still remains unclear.
We assume that two possible mechanisms exist. One is the direct interaction of SMF with free active oxygen forms (free radicals)
affected by their membrane processes and related with the physiological functions. Another possible mechanism might be related
to dynamic regulation of inflammation healing process. 相似文献