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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   
202.
邵林广  陈斌  黄霞  钱易 《环境科学》1994,15(6):51-53
用内填YDT弹性立体填料的水解(酸化)-缺氧-好氧固定床生物膜系统焦化废水。结果:当进水COD和NH3-N浓度分别为1065mg/L和253mg/L,系统水力停留时间(HRT)为33.5h,混合液回流比为3.6时,出水COD约为180mg/L,NH3-N为5mg/L,COD和NH3-N的去除率分别达83%和98%。  相似文献   
203.
聚酯(PET)废塑料分离回收方法研究   总被引:3,自引:0,他引:3  
日常用的饮料瓶是聚酯和高密度聚乙烯为原是制成的,因而聚酯废塑料瓶是数量较多和回收价值高的一种塑料,本研究首先对聚酯废料瓶进行破碎,然后采用气流分选,清洗净化和水浮选组合工艺进行PET和HDPE及塑纸的分离回收。PET和HDPE的回收率分别为97%和95%,同时通过清洗净化可使回收的PET纯度达96%以上,该PET是一种用途广的优良塑料原料。  相似文献   
204.
二氧化钛薄膜光催化性能的影响因素及提高途径   总被引:16,自引:0,他引:16  
TiO2薄膜光催化技术有广阔的应用前景,在国内外得到了广泛的研究。介绍了TiO2薄膜光催化降解的研究现状,指出了影响薄膜光催化性能的若干因素和提高薄膜光催化效率的相应手段。另外,对金属复合、半导体复合对TiO2薄膜光催化性能的影响和可见光催化的研究现状进行了评述。  相似文献   
205.
光活性二氧化钛膜的制备与应用   总被引:1,自引:0,他引:1  
自80年代末以来,光活性膜由于诱人的应用前景而成为环境领域的研究热点。本文主要介绍溶胶—凝胶法等制备二氧化钛膜的方法及其原理,并根据基于二氧化钛膜的光催化技术的特点简单地讨论了光活性二氧化钛膜的可能应用领域。  相似文献   
206.
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   
207.
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   
208.
• Pesticide residuals on mulching film of Shandong, Tianjin and Hebei. • Detected 29 pesticides in soil and 30 in mulching film. • Pesticides on plastic films: 86.4‒22213.2 ng/g and in soil: 9.3‒535.3 ng/g. • Pesticides on plastic films 20 times higher than in soil. Plastic debris as new pollutants attracts much attention in the recent years. The plastic mulching films is one of the most important plastic debirs source in the environment. The aim of this work was to investigate the current status of pesticide residues on the plastic mulching films. Based on the QuEChERS method, multi-residue methods for detection of pesticide residues with gas chromatography tandem mass spectrum (GC-MS) and high performance liquid chromatography tandem mass spectrum (HPLC-MS) were developed for the analysis of the pesticides residues in plastic film and soil samples from Tianjin, Hebei and Shandong. The total concentrations of pesticide residues were in the range of 86.4‒22213.2 ng/g in plastic film debris, which was about 20 times higher than that in soil (9.3‒535.3 ng/g). Residual level of pesticides varied greatly in different samples. The historical usage and recent application of pesticides were the main sources for pesticide residues on plastic films and soil. In short, plastic mulching films could act as a sink for pesticides in farmland and the ubiquitous pesticide residues on plastic films should draw more attention.  相似文献   
209.
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   
210.
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   
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