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991.
In this work, Er3+:YAlO3/ZnO–TiO2 and ZnO–TiO2 composites were prepared by the ultrasonic dispersion and liquid boiling method. In succession, they were then characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Acid red B as a model dye compound was degraded under solar light irradiation to evaluate the photocatalytic activities of the Er3+:YAlO3/ZnO–TiO2 and ZnO–TiO2 composites. We found that the photocatalytic activity of ZnO–TiO2 composite can be enhanced by adding an appropriate amount of Er3+:YAlO3. We reviewed influencing factors, such as Er3+:YAlO3 content, heat-treated temperature and heat-treated time on the photocatalytic activity of the Er3+:YAlO3/ZnO–TiO2 composites. In addition, the effects of solar light irradiation time, dye initial concentration, Er3+:YAlO3/ZnO–TiO2 amount and solution acidity on the photocatalytic degradation of acid red B dye in aqueous solution were investigated in detail. Simultaneously, the degradation and comparison of other dyes such as methyl orange (MO), rhodamine B (RM-B), azo fuchsine (AF), congo red (CG-R) and methyl blue (MB) were also reviewed. In addition, we attempted to explore both the principle of possible excitation of Er3+:YAlO3/ZnO–TiO2 under solar light irradiation and the mechanism of photocatalytic degradation.  相似文献   
992.
Membrane damage related to morphological change in Vero cells is a sensitive index of the composite biotoxicity of trace lipophilic chemicals. However, judging whether the morphological change in Vero cells happens and its ratio are difficult because it is not a quantitative characteristic. To find biomarkers of cell morphological change for quantitatively representing the ratio of morphological changed cell, the mechanism of cell membrane damage driven by typical lipophilic chemicals, such as trichlorophenol (TCP) and perfluorooctanesulphonate (PFOS), was explored. The ratio of morphologically changed cells generally increased with increased TCP or PFOS concentrations, and the level of four major components of phospholipids varied with concentrations of TCP or PFOS, but only the ratio of phosphatidylcholine (PC)/phosphatidylethanolamine (PE) decreased regularly as TCP or PFOS concentrations increased. Analysis of membrane proteins showed that the level of vimentin in normal cell membranes is high, while it decreases or vanishes after TCP exposure. These variations in phospholipid and membrane protein components may result in membrane leakage and variation in rigid structure, which leads to changes in cell morphology. Therefore, the ratio of PC/PE and amount of vimentin may be potential biomarkers for representing the ratio of morphological changed Vero cell introduced by trace lipophilic compounds, thus their composite bio-toxicity.  相似文献   
993.
从学校、企业、政策等方面分析了现有“产学合作”运行机制存在的问题,从知识机制、动力机制、调控机制、利益机制、风险机制及环境机制五个角度分析了校企“产学合作”机制发展的现状。以中国环境管理干部学院环境信息管理专业为例,提出了构建合理的“产学合作”评价体系的完整流程,流程中涵盖了评价的重要指标,从不同角度反映了合作的效果。  相似文献   
994.
Environmental Science and Pollution Research - Sleep problems are common in modern society and may be related to environmental chemicals. The objective of this study is to investigate the...  相似文献   
995.
Xu  Zhixiang  Jia  Yue  Huang  Bin  Zhao  Dimeng  Long  Xin  Hu  Siyuan  Li  Caiqing  Dao  Guohua  Chen  Bo  Pan  Xuejun 《Environmental Chemistry Letters》2023,21(4):2285-2309
Environmental Chemistry Letters - With the extensive production and use of antibiotics for medicinal and veterinary purposes, antibiotics and genes that code for antibiotic resistance are now...  相似文献   
996.
Environmental Science and Pollution Research - Given the relatively harsh natural environment in semi-arid valley areas, the attraction and radiation functions of semi-arid valley cities have...  相似文献   
997.
Tebuconazole is a chiral triazole fungicide used as raceme in a variety of agricultural applications. Earlier studies showed that tebuconazole is toxic to many non-target aquatic organisms but relative data for tebuconazole enantiomers are lacking. Thus, goal of this study was to evaluate and compare the toxicity of rac- and S-tebuconazole with Daphnia magna at both acute and chronic levels according to Organization for Economic Cooperation and Development (OECD) guidelines 202 and 211 respectively, to provide some guidelines for optimizing chiral pesticides application and management. The exposure concentrations were 0.1, 0.5, 1, 2, 4, 8, 10 mg L?1 for both rac- and S-tebuconazole and their 48-h EC50 values to D. magna were 3.53 (3.32–3.78) and 2.74 (2.33–3.10) mg L?1 respectively, indicating that these both are medium toxic to D. magna with no significant toxicity difference at acute level. In chronic test, <24-h old D. magna were exposed to 0.01, 0.05, 0.10, 0.20, and 0.40 mg L?1 of rac- and S-tebuconazole with one blank and one solvent control for 21 days according to OECD guideline 211. Four developmental (molting rate, days to the 1st and 3rd brood, and body length) and five reproductive (size of the 1st and 3rd brood, number of broods, and number of neonates) parameters for each D. magna were determined. Results showed that both rac- and S-tebuconazole significantly reduced the reproduction and impacted the development of D. magna at concentrations of 0.05 mg L?1 or higher. Furthermore, S-tebuconazole was more toxic than raceme, and the difference between effects on the same parameters induced by rac- and S-tebuconazole was statistically significant. These results demonstrated that the chronic toxicity of S-tebuconazole might be underestimated in general use, and further studies should focus more on the biological behaviors of enantiomers and not just the raceme of tebuconazole and other chiral pesticides in the environment.  相似文献   
998.
高酚焦化废水萃取脱酚预处理   总被引:1,自引:0,他引:1  
为了降低高酚焦化废水中挥发酚的浓度,实验研究了磷酸三丁酯煤油溶液在不同条件下对高酚焦化废水进行萃取脱酚预处理的效果。结果表明,萃取时间为8min,磷酸三丁酯煤油浓度为30%,温度低于40%,pH低于8.0,萃取比(油/水)R=1:2时,经过萃取后分水挥发酚浓度由4165mg降低到127.62mg/L,去除率高达96.94%,为后续生化处理奠定了基础。而萃取剂经过氢氧化钠溶液反萃取再生后,萃取剂的回收利用率可达94.25%以上。  相似文献   
999.
Abstract

The objective of social development is to construct a harmonious society. In China, the key to a harmonious society is the happiness of more than 900 million farmers living in the rural areas. This study aimed to measure rural residents’ subjective well-being (SWB) through the day reconstruction method, as well as to analyze SWB’s influencing factors through a variety of statistical methods. The results showed that the average U index was 12.79%, indicating that respondents were unhappy 12.79% of the time. Twenty-seven percent of the population had a U index greater than 0, with the average value being 47%, indicating that these people were unhappy 47% of the time. The study also found that SWB varied according to the characteristics of the respondents. Logistic regression analysis showed that social and demographic factors, including age, education, county, household size, generation number, per capita income, migration status and social networking, which significantly affected rural residents’ SWB. The size of the impact varied with the different factors.  相似文献   
1000.
稠油热采作业是海上平台一项高风险作业,南堡油田是多元热流体吞吐稠油热采作业的实验基地,通过几年的现场实践和持续改进,形成了热采等高风险作业系统的安全管理方法.在人员管理方面实行个体差异化管理,人员编制上采取定编定岗制度,根据工作态度实行刚性和弹性管理.以体系为基础,细化安全工具,推出区域承包责任制、五分钟示范教育、安全协管员、作业许可证双签、四定原则和过程风险控制等一系列有效措施.通过制约因素分析、细化工作界面、关键参数跟踪、阶段性纠偏总结会等提高质量管理.该套风险控制方法确保了八井次热采以及其他多项高风险作业的安全顺利进行,并被固化下来组成了油田的安全文化.  相似文献   
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