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201.
生产性四级转盘生物膜活性的测定与分析 总被引:2,自引:0,他引:2
本文以处理生物制品废水的生产性四级转盘的生物膜为材料,在监测转盘对废水污染指标(BOD_5、COD_(cr)、挥发酚)降解性能的同时,测定了各级转盘生物膜的挥发性固体(VS)、活性微生物数目(AMN)以及TTC-脱氢酶活性(TTC-DHA)等活性参数,并分析讨论了VS、AMN、TTC-DHA与转盘级数的关系以及TTC-DHA与VS的相关性等问题。结果表明,TTC-DHA可能将会成为测定转盘生物膜活性的有效参数。 相似文献
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Increasing micro plastic concentration in the marine environment is a severe threat to the marine ecosystem and indirectly to human society depending on the marine environment. Also, the surface and subsurface water quality parameters are the indicators of the usability of the water sources for human activities. The primary source of micro plastic is the water river systems from land to sea. This study establishes a correlation between water quality parameters and micro plastic concentration to find the most suitable quality parameter for finding the micro plastic concentration in urban coastal estuaries of Chennai coast, Tamil Nadu, India. Twenty samples from Adyar and Cooum estuaries were collected, with ten each on August 2019 and August 2020. They are tested for temperature pH, EC, Turbidity, TDS, DO, BOD, COD, Salinity and micro plastic concentrations. Correlation tests such as Pearson's and Spearman's are performed based on the initial Normality and Homogeneity test. The results show that all the parameters are significantly not correlated with the Micro plastic Concentration, and Micro plastic Concentration is considered an independent factor. 相似文献
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Loretta Rowley Kevin A. Johnson 《Environmental Communication: A Journal of Nature and Culture》2018,12(6):825-839
The documentary film Blackfish has made a splash at the box office, impacting millions of viewers and prompting calls to legislatively prohibit orcas from being held in captive environments. This essay analyzes Blackfish in terms of its anthropomorphic communication techniques that attribute human qualities to orcas. We introduce the term “anthropomorphic anthropocentrism” to argue that the anthropomorphic construction of orcas in Blackfish may well be a story that is more about what it means to be human than a story about what it means to be orca. Furthermore, we explain the importance of anthropomorphic anthropocentrism as an analytical tool that navigates environmental and ecological frameworks. We conclude that anthropomorphic anthropocentrism’s analysis of anthropomorphic rhetoric and the human epistemological assumptions it reflects, when taken together, offer significant insights into the ways environmental communication creates and/or disrupts human–nature relationships. 相似文献
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Baoyuan Guo Jiao Meng Xinyu Wang Chengnan Yin Weiyu Hao Baiwen Ma Zhang Tao 《Frontiers of Environmental Science & Engineering》2020,14(1):2
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为了探究动载作用下GFRP(玻璃纤维)-砂浆管的动态拉伸破坏特性,采用分离式SHPB试验装置对2种空心率的水泥砂浆管和GFRP-砂浆管进行动态拉伸试验。结果表明:空心率越小、冲击气压和壁厚越大,试件峰值抗拉强度越大;GFRP-砂浆管的峰值抗拉强度随GFRP管壁厚的增大而不断增大,在空心率为0.292时,峰值抗拉强度随GFRP管壁厚增大呈对数函数递增,而在空心率0.187时,峰值抗拉强度随GFRP管壁厚增大呈指数函数递增;无GFRP管时水泥砂浆管呈对称四块破碎,GFRP-砂浆管在0.5~0.7 MPa冲击气压下仅有细小裂纹产生,在0.8 MPa冲击气压下,与入射杆接触部分产生“楔形”破坏,但总体保持为管状、破坏程度仍低于水泥砂浆管,表明GFRP管对水泥砂浆管具有较好的保护作用,可有效提高其动态抗拉强度。 相似文献
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Akio Kamimura Eisuke Konno Shigehiro Yamamoto Takeru Watanabe Kazuo Yamada Fumiaki Tomonaga 《Journal of Material Cycles and Waste Management》2009,11(2):133-137
The synthesis of recycled plastics from recovered monomeric materials obtained from the depolymerization reaction of fiber-reinforced
plastics (FRP) was examined. The depolymerization reaction of FRP in the presence of N,N-dimethylaminopyridine (DMAP) smoothly yielded the corresponding monomers, which mainly consisted of dimethyl phthalates.
The polymerization reaction with this monomer failed to form the corresponding unsaturated polyesters due to contamination
by N-methyl-4-pyridone, a decomposition product of DMAP. An efficient purification of the recovered monomer was achieved by washing
with water, and the purified monomer successfully yielded the corresponding polymers. A hardness test revealed that the polymers
were as hard as the polyester made from virgin materials. The present modification provides a practical method for the preparation
of recycled plastics from depolymerized plastics. 相似文献