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81.
Over the last several decades, the scientific community has replaced the ‘acts of god’ explanations for disasters with a view that disasters are actually ‘acts of nature,’ and more recently, ‘acts of human behavior and decision making.’ Despite the secular orientation of contemporary disaster research, religious beliefs still govern people’s interpretations of natural events across many continents and cultures. Using a case study of a rural Sherpa community in Nepal, this paper responds to the challenge of linking religion and disaster risk in the context of a climate change-induced glacial lake outburst flood hazard. Data collection employed ethnographic techniques including participant observation and 53 interviews with community members. Results indicate that the case study community’s religious belief system influences how they interpret and respond to the glacial lake hazard, although their beliefs co-exist with more scientific interpretations of risk. Rather than being immobilised by their belief system, we found that religious aspects like rituals and prayer can enhance social cohesion and contribute to capacities for coping with fear and uncertainty in this community. We assert that religion can yield valuable resources to glacial lake risk reduction strategies, which will benefit from incorporating social-cultural factors more profoundly.  相似文献   
82.
农药混配制剂环境风险评估现状与展望   总被引:1,自引:0,他引:1  
本文综述了欧洲和美国农药混配制剂的环境风险评估方法。详细介绍了欧洲食品安全局(EFSA)评估体系中的2种方法,即,基础的"整体测试法"和近年来提倡的"基于组分的方法"。"基于组分的方法"的特点是以浓度加和模型(CA模型)作为默认假设进行初级评估,以独立作用模型(IA模型)等作为高级评估手段的农药混配制剂环境风险评估方法。此外,本文还介绍了模型偏差率(MDR)、毒性相似度及毒力单元(TU)等概念以及混配制剂风险评估流程。本文的目的旨在为建立我国农药混配制剂的环境风险评估方法体系提供参考。  相似文献   
83.
Pesticides cause serious environmental and health problems both to humans and animals. The aim of this review is to discuss selected herbicides and fungicides regarding their mode of action and their influence on basic oxidative stress parameters and endocrine disruption properties tested in selected cell cultures in vitro. Because of numerous difficulties which animal studies are subject to, cell cultures are an excellent experimental model reflecting human exposure to different pesticides through all relevant routes. This experimental model can be used to monitor aggregate and cumulative pesticide exposures.  相似文献   
84.

In the present study, we isolated three novel bacterial species, namely, Staphylococcus sp., Bacillus circulans–I, and Bacillus circulans–II, from contaminated soil collected from the premises of a pesticide manufacturing industry. Batch experiments were conducted using both mixed and pure cultures to assess their potential for the degradation of aqueous endosulfan in aerobic and facultative anaerobic condition. The influence of supplementary carbon (dextrose) source on endosulfan degradation was also examined. After four weeks of incubation, mixed bacterial culture was able to degrade 71.82 ± 0.2% and 76.04 ± 0.2% of endosulfan in aerobic and facultative anaerobic conditions, respectively, with an initial endosulfan concentration of 50 mg l?1. Addition of dextrose to the system amplified the endosulfan degradation efficiency by 13.36 ± 0.6% in aerobic system and 12.33 ± 0.6% in facultative anaerobic system. Pure culture studies were carried out to quantify the degradation potential of these individual species. Among the three species, Staphylococcus sp. utilized more beta endosulfan compared to alpha endosulfan in facultative anaerobic system, whereas Bacillus circulans–I and Bacillus circulans–II utilized more alpha endosulfan compared to beta endosulfan in aerobic system. In any of these degradation studies no known intermediate metabolites of endosulfan were observed.  相似文献   
85.
The increasing concentrations impact (0.02, 0.2 and 2 mg L−1) of a Sterol Biosynthesis Inhibitor (SBI) fungicide, propiconazole, was evaluated on development and sterol metabolism of two non-target organisms: mycorrhizal or non-mycorrhizal transformed chicory roots and the arbuscular mycorrhizal fungus (AMF) Glomus irregulare using monoxenic cultures. In this work, we provide the first evidence of a direct impact of propiconazole on the AMF by disturbing its sterol metabolism. A significant decrease in end-products sterols contents (24-methylcholesterol and in 24-ethylcholesterol) was observed concomitantly to a 24-methylenedihydrolanosterol accumulation indicating the inhibition of a key enzyme in sterol biosynthesis pathway, the sterol 14α-demethylase like in phytopathogenic fungi. A decrease in end-product sterol contents in propiconazole-treated roots was also observed suggesting a slowing down of the sterol metabolism in plant. Taken together, our findings suggest that the inhibition of the both AM symbiotic partners development by propiconazole results from their sterol metabolism alterations.  相似文献   
86.
以堇青石蜂窝陶瓷(CC)为载体,采用浸渍法制备了堇青石负载Pd和过渡金属混合氧化物催化剂,记作Pd-M-Mn(M=Cu,Co,Fe,Ni)/CC。实验结果表明:Pd-Co-Mn/CC催化剂的催化活性最高;随着Pd负载量的增加,CO转化率提高;当Pd负载量为1.00%时,反应温度为150℃时CO转化率达到98%,200℃时CO转化率达到100%;在反应温度150℃条件下,Pd-Co-Mn/CC催化剂(Pd负载量1.00%)的CO转化率在前30h内小幅度下降,随后稳定在90%以上,反应100h后,催化剂表面颜色由黑色变为棕褐色。  相似文献   
87.
Abstract

The biotransformation of the nonylphenol isomer [ring-U-14C]-4-(3′,5′-dimethyl-3′-heptyl)-phenol (4-353-NP, consisting of two diastereomers) was studied in soybean and Agrostemma githago cell suspension cultures. With the A. githago cells, a batch two-liquid-phase system (medium/n-hexadecane 200:1, v/v) was used, in order to produce higher concentrations and amounts of 4-353-NP metabolites for their identification; 4-353-NP was applied via the n-hexadecane phase. Initial concentrations of [14C]-4-353-NP were 1 mg L?1 (soybean), and 5 and 10 mg L?1 (A. githago). After 2 (soybean) and 7 days (A. githago) of incubation, the applied 4-353-NP was transformed almost completely by both plant species to four types of products: glycosides of parent 4-353-NP, glycosides of primary 4-353-NP metabolites, nonextractable residues and unknown, possibly polymeric materials detected in the media. The latter two products emerged especially in soybean cultures. Portions of primary metabolites amounted to 19–22% (soybean) and 21–42% of applied 14C (A. githago). After liberation from their glycosides, the primary 4-353-NP metabolites formed by A. githago were isolated by HPLC and examined by GC-EIMS as trimethylsilyl derivatives. In the chromatograms, eight peaks were detected which due to their mass spectra, could be traced back to 4-353-NP. Seven of the compounds were side-chain monohydroxylated 4-353-NP metabolites, while the remaining was a (side-chain) carboxylic acid derivative. Unequivocal identification of the sites of hydroxylation/oxidation of all transformation products was not possible. The main primary metabolites produced by A. githago were supposed to be four diastereomers of 6′-hydroxy-4-353-NP (about 80% of all products identified). It was concluded that plants contribute to the environmental degradation of the xenoestrogen nonylphenol; the toxicological properties of side-chain hydroxylated nonylphenols remain to be examined.  相似文献   
88.
摘要以镁盐、铝盐、纯碱和烧碱为原料制备了一种多孔镁铝复合氧化物(P—Mg3.1AlO4.6),其比表面积、平均孔径和总孔容分别为206.3m2/g、8.961nm和0.4208cm3/g。研究了这种多孑L材料对水溶液中cr(VI)的吸附性能,在25~45qC时,静态吸附量为82.32~141.7mg/g;当初始浓度100mg/L、流速5mL/min、床层高度10cm和pH=6时,半穿透时间、半穿透吸附量和饱和吸附量分别为406rain、49.28ing/g和51.30Ing/g;拟合参数及误差分析表明,cr(Ⅵ)在P—M敬。AIO4.6上的静态吸附过程符合Freundlich等温方程式和伪二级动力学方程,Yoon·Nelson模型能很好地预测cr(Ⅵ)在P—Mg3.1A104.6上的动态穿透曲线。  相似文献   
89.
根据大港油田12井综合废水的污染特征,提出了"混凝-内电解-H2O2氧化"三步处理的方法。实验结果表明:三步法处理后可以使原水的CODcr从4930mg/L降低到128mg/L,去除率达到97%。处理后水质达到国家《污水综合排放标准》(GB8978-1996)二级标准要求。  相似文献   
90.
建设绿色企业文化是秦皇岛港实现绿色发展的前提,对港口的发展有深远的意义和重要作用.秦皇岛港应从强化领导意识、提高职工素质、完善绿色制度体系、构建绿色企业形象等方面入手建设港口绿色企业文化.  相似文献   
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