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131.
采用反相微悬浮乳液聚合技术制备了β-环糊精(β-CD)微球,用丁二酸酐对β-CD微球进行化学改性,制备了pH敏感性β-CD(pH-β-CD)微球.通过傅里叶红外光谱仪和扫描电子显微镜对微球的结构、粒径和形貌进行了表征.探讨了亚甲基蓝模拟染料废水pH、吸附时间和微球加入量对亚甲基蓝吸附性能的影响.实验结果表明,在亚甲基蓝模拟染料废水pH为10.0、吸附时间为90 min的条件下,当pH-β-CD微球加入量为50 mg时,pH-β-CD微球吸附量为16.1 mg/g;当pH-β-CD微球加入量为250 mg时,pH-β-CD微球对亚甲基蓝的脱色率达96.2%. 相似文献
132.
选择性催化还原烟气脱硝技术在玉环电厂4×1000MW机组上的应用 总被引:2,自引:1,他引:1
以华能玉环电厂4×1000MW机组增设烟气选择性催化还原法(SCR)脱硝装置的技术改造为例,简要介绍了玉环电厂原机组增加SCR脱硝系统的工艺构成和流程特点、设计参数、总体布置,并对该工程中相关设备的改造进行了描述,为我国大型燃煤机组的脱硝改造工程提供参考。 相似文献
133.
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135.
V. L. Finkenstadt C.-K. Liu P. H. Cooke L. S. Liu J. L. Willett 《Journal of Polymers and the Environment》2008,16(1):19-26
Sorbitol and glycerol were used to plasticize sugar beet pulp-poly(lactic acid) green composites. The plasticizer was incorporated
into sugar beet pulp (SBP) at 0%, 10%, 20%, 30% and 40% w/w at low temperature and shear and then compounded with poly(lactic
acid) (PLA) using twin-screw extrusion and injection molding. The SBP:PLA ratio was maintained at 30:70. As expected, tensile
strength decreased by 25% and the elongation increased. Acoustic emission (AE) showed correlated debonding and fracture mechanisms
for up to 20% w/w plasticizer and uncorrelated debonding and fracture for 30–40% sorbitol and 30% glycerol content in SBP–PLA
composites. All samples had a well dispersed SBP phase with some aggregation in the PLA matrix. However, at 40% glycerol plasticized
SBP–PLA composites exhibited unique AE behavior and confocal microscopy revealed the plasticized SBP and PLA formed a co-continuous
two phase system.
相似文献
V. L. FinkenstadtEmail: |
136.
Suzhen Qi Xue Liu Lizhen Zhu Xiaofeng Chen 《Journal of environmental science and health. Part. B》2018,53(3):171-175
Tebuconazole is a chiral trizole fungicide and widely used in many crops for controlling disease. Tebuconazole is potential toxic to some aquatic organisms but relative information of its isomers is scarce. To detect the endocrine disrupting effects and difference of rac-, R-, and S-tebuconazole, the chitinase activity in Daphnia magna and chitobiase activity in each test medium were used as biomonitors after a 14-day exposure. Results showed that chitinase activity was significantly reduced by rac-, R-, and S-tebuconazole. The chitobiase activity in the test medium was reduced by rac- and R-tebuconazole before day 10, and only one peak was observed at day 10 or day 12 compared with two obvious peaks in the control group (days 6 and 12). S-tebuconazole delayed and reduced the reproduction of D. magna, but did not delay the first chitobiase activity peak, whereas the second peak could not be characterized as the exposure concentration and time increased. Compared with chitinase activity, chitobiase activity can still be used as a rudimentary model for identifying molt-interfering xenobiotics, and further studies should focus on the analysis of correlations between these parameters. 相似文献
137.
Long-lasting expansion of haze pollution in China has already presented a stern challenge to regional joint prevention and control. There is an urgent need to enlarge and reconstruct the coverage of joint prevention and control of air pollution in key area. Air quality models can identify and quantify the regional contribution of haze pollution and its key components with the help of numerical simulation, but it is difficult to be applied to larger spatial scale due to the complexity of model parameters. The time series analysis can recognize the existence of spatial interaction of haze pollution between cities, but it has not yet been used to further identify the spatial sources of haze pollution in large scale. Using econometric framework of time series analysis, this paper developed a new approach to perform spatial source apportionment. We applied this approach to calculate the contribution from spatial sources of haze pollution in China, using the monitoring data of particulate matter (PM2.5) across 161 Chinese cities. This approach overcame the limitation of numerical simulation that the model complexity increases at excess with the expansion of sample range, and could effectively deal with severe large-scale haze episodes. 相似文献
138.
He Genhe Wang Xiaodong Liu Xu Xiao Xiaoyu Huang Shoucheng Wu Jichun 《Russian Journal of Ecology》2018,49(6):524-533
Russian Journal of Ecology - The present study characterized the nutrients availability of three rare earth tailings deserted in different time stages in Southern Jiangxi of China, and revealed the... 相似文献
139.
T酸一次洗水初步处理的研究 总被引:4,自引:0,他引:4
采用重氮化-偶合-混凝沉淀和重氮化-混凝沉淀两种方法对T酸一次洗水的初步处理进步了研究。T酸一次洗水经两种方法处理后,COD去除率分别为61.3%、50.5%,色度去除率分别为74.6%、71%。 相似文献
140.
Mianzhi Wang Yongxue Sun Peng Liu Jing Sun Qin Zhou Wenguang Xiong Zhenling Zeng 《Environmental science and pollution research international》2017,24(26):20949-20958
This study aimed to determine the occurrence, abundance, and fate of nine important antimicrobial resistance genes (ARGs) (sul1, sul2, tetB, tetM, ermB, ermF, fexA, cfr, and Intl1) in the simulated soil and pond microcosms following poultry and swine manure application. Absolute quantitative PCR method was used to determine the gene copies. The results were modeled as a logarithmic regression (N?=?mlnt?+?b) to explore the fate of target genes. Genes sul1, Intl1, sul2, and tetM had the highest abundance following the application of the two manure types. The logarithmic regression model fitted the results well (R 2 values up to 0.99). The reduction rate of all genes (except for the genes fexA and cfr) in manure-pond microcosms was faster than those in manure-soil microcosms. Importantly, sul1, intl1, sul2, and tetM had the lowest reduction rates in all the samples and the low reduction rates of tetM was the first time to be reported. These results indicated that ARG management should focus on using technologies for the ARG elimination before the manure applications rather than waiting for subsequent attenuation in soil or water, particularly the ARGs (such as sul1, intl1, sul2, and tetM investigated in this study) that had high abundance and low reduction rate in the soil and water after application of manure. 相似文献