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591.
592.
Chen Guowei Xi Pengge Xu Deqian Yu Hanqing 《Frontiers of Environmental Science & Engineering in China》2007,1(1):63-66
In order to study the minimization of excess sludge production, the reduction in the excess sludge production in the presence
of an inhibitor and uncoupler was studied in this work. The experimental results show that such an addition could effectively
reduce the production of excess sludge. With the energy uncoupling model established in this work, energy uncoupling coefficient
(E
u) was used to evaluate the reduction in excess sludge production. The energy uncoupling coefficients in the presence of dinitrophenol
(dNP), Zn2+, and Cu2+ was 0.75, 0.46, and 0.18, respectively. The analysis demonstrated that energy spilling occurred in the presence of dNP, and
that dNP was an effective uncoupler for reducing the production of excess activated sludge without affecting the microbial
respiration activity. 相似文献
593.
特非那丁格氏工序的清洁生产 总被引:1,自引:0,他引:1
采用合理工艺,使生产过程废物最少化是清洁生产的主要内容之一,在分析特非那丁格氏工序污染物产生的基础上,通过改进工艺,将过去排放的有机溶媒回收套用,减少污染物排放的同时,增加了经济效益。 相似文献
594.
在市场经济条件下推行清洁生产 总被引:1,自引:0,他引:1
探讨了如何在市场经济下推行清洁生产。强调“环保靠政府”,环保主管部门要尽快着手建立“废物审计制度”,并就该项制度与8项环保制度相衔接进行了讨论。 相似文献
595.
596.
597.
598.
石油勘探开发过程中推行清洁生产初探 总被引:1,自引:0,他引:1
王丹昶 《石油化工环境保护》2003,26(4):8-10
就如何搞好石油勘探开发过程中的清洁生产进行了研究和探讨,总结了现行的清洁生产技术。对搞好石油勘探开发过程中的环保工作有一定的作用。 相似文献
599.
Legume-based pastures in Australasia are predominantly perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.). These pastures have disadvantages such as limitations in the production and persistence of white clover and ryegrass in drought prone regions. With the increasing interest in organic agriculture, more complex pasture mixtures are seen as an alternative to the standard ryegrass-white clover (RWC) pasture. Although anecdotal evidence exists to support the benefits of alternative pastures, there is insufficient scientific evidence to support or refute these claims. The present study was conducted to compare three different alternative multi-species (mixed herb leys) (MSP) pastures with the standard RWC pasture with and without irrigation, in terms of biomass and biological nitrogen fixation (BNF) over a period of 1 year under field conditions in Canterbury, New Zealand. Isotopic dilution technique involving field 15N-microplots were used to measure BNF. Irrigation doubled dry matter yields (DMY) of all pastures compared with those under dryland. There was no significant difference between DMY of all pastures under dryland. However, under irrigation, MSP pastures out-yield RWC pasture in total and legume DMY. Red clover MSP produced significantly lower DMY than the comprehensive or lucerne MSP treatment, probably due to the ability of lucerne in extracting water from deeper soil depth. Seasonal changes in plant composition varied according to the species sown, soil moisture status and temperature. Total and seasonal amounts of N2 fixed followed the same trend as the DMY and were related to the DMY of legumes. On average, about 26–34 kg N was fixed per tonne of legume DMY, showing a uniformity across all pastures. Overall, based on the present results of 1-year study, the MSP pastures tend to result in higher DMY, BNF and legume growth compared with that of the RWC pasture, provided irrigation is available. With increased BNF, these irrigated MSP pastures may provide high quality feed to grazing animals. 相似文献
600.
在回顾市场机制在ISO14000标准成功实施中的作用基础上,对我国清洁生产推动中市场机制的缺乏而影响清洁生产的实施效果进行了反思,提出了基于市场的清洁生产推动机制的设想。 相似文献