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101.
胡冉  曹波 《重庆环境科学》1998,20(4):47-49,59
选用Ames试验、小鼠骨髓细胞微核实验和小鼠显性致死突变试验对新型食品添加剂“赛力奇”的致突变性进行了检验。结果表明:三项试验的结果均生。根据国家《食品安全性毒理学评价程序(试行)》的规定,认为“赛力奇”无致突变性。  相似文献   
102.
生命周期评价的应用,内涵与挑战   总被引:2,自引:0,他引:2  
王毅  魏江 《环境导报》1998,(5):27-29
从环境问题与可持续发展出发,指出生命周期评价是在产品层次上实现可持续发展的一种理论评价工具,并探讨了生命周期评价的内涵,论述产品生命周是进行生命周期评价的客观依据,详细探讨应用生命周期评价存在的问题,指出进一步研究生命周期评价的方向。  相似文献   
103.
海洋环境责任保险   总被引:4,自引:0,他引:4  
随着海洋环境问题日益尖锐,可能影响海洋环境的作业者,一旦造成海洋环境污染必将面对巨额的责任赔偿与罚款,作业者为降低自己的风险损失,政府为增强其治理及控制污染的能力,作业者不得不购买海洋环境责任保险,本文着重分析了海洋环境责任保险的发展历史,依法强制实行环境责任保险的必要性及海洋环境责任保险的责任范围。  相似文献   
104.
Antibiotics have been identified as obesogens contributing to the prevalence of obesity. Moreover, their environmental toxicity shows sex dependence, which might also explain the sex-dependent obesity observed. Yet, the direct evidence for such a connection and the underlying mechanisms remain to be explored. In this study, the effects of tetracycline, which is a representative antibiotic found in both environmental and food samples, on Drosophila melanogaster were studied with consideration of both sex and circadian rhythms (represented by the eclosion rhythm). Results showed that in morning-eclosed adults, tetracycline significantly stimulated the body weight of females (AM females) at 0.1, 1.0, 10.0 and 100.0 µg/L, while tetracycline only stimulated the body weight of males (AM males) at 1.0 µg/L. In the afternoon-eclosed adults, tetracycline significantly stimulated the body weight of females (PM females) at 0.1, 1.0 and 100.0 µg/L, while it showed more significant stimulation in males (PM males) at all concentrations. Notably, the stimulation levels were the greatest in PM males among all the adults. The results showed the clear sex dependence of the obesogenic effects, which was diminished by dysrhythmia. Further biochemical assays and clustering analysis suggested that the sex- and rhythm-dependent obesogenic effects resulted from the bias toward lipogenesis against lipolysis. Moreover, they were closely related to the preference for the energy storage forms of lactate and glucose and also to the presence of excessive insulin, with the involvement of glucolipid metabolism. Such relationships indicated potential bridges between the obesogenic effects of pollutants and other diseases, e.g., cancer and diabetes.  相似文献   
105.
城市污水厂污泥由于产生量大且成分复杂,如何对它进行稳定化、无害化处理已越来越受到人们的关注。本研究基于好氧发酵仓式堆肥系统,研究了城市污泥处理过程中温度、含水率、pH、有机质、水溶性有机碳、总氮和发芽指数等指标参数的变化规律。研究结果表明:当物抖初始含水率控制在65%左右时,在强制通风量112.5m^3/12hr,搅拌频率30min/24hr的工艺条件下,堆肥过程可以实现顺利升温并在55℃以上维持3天,满足杀灭致病茵要求的条件;14天反应用期结束时,物抖含水率、水溶性有机碳和有机质含量显著降低,堆肥产品腐熟,卫生学指标达到了美国EPA污泥产品A类标准;得列的污泥产品成为性质优良的土壤质量调节荆。  相似文献   
106.
本法用Ag/S离子选择电极测定废水中的硫化物,测定浓度范围0.1~1000.0mg/l,方法精密度为4.3%,回收率为P2.5%,检出限为0.1mg/l。大多数离子不干扰测定,该法简便快速,适用于例行监测。  相似文献   
107.
Ambient particulate matter (PM) can cause adverse health effects via their ability to produce Reactive Oxygen Species (ROS). Water-Soluble Organic Compounds (WSOCs), a complex mixture of organic compounds which usually coexist with Transition Metals (TMs) in PM, have been found to contribute to ROS formation. However, the interaction between WSOCs and TMs and its effect on ROS generation are still unknown. In this study, we examined the ROS concentrations of V, Zn, Suwannee River Fulvic Acid (SRFA), Suwannee River Humic Acid (SRHA) and the mixtures of V/Zn and SRFA/SRHA by using a cell-free 2′,7′-Dichlorodihydrofluorescein (DCFH) assay. The results showed that V or Zn synergistically promoted ROS generated by SRFA, but had an antagonistic effect on ROS generated by SRHA. Fluorescence quenching experiments indicated that V and Zn were more prone to form stable complexes with aromatic humic acid-like component (C1) and fulvic acid-like component (C3) in SRFA and SRHA. Results suggested that the underlying mechanism involving the fulvic acid-like component in SRFA more tending to complex with TMs to facilitate ROS generation through π electron transfer. Our work showed that the complexing ability and complexing stability of atmospheric PM organics with metals could significantly affect ROS generation. It is recommended that the research deploying multiple analytical methods to quantify the impact of PM components on public health and environment is needed in the future.  相似文献   
108.
Boundaries between different forest types in Changbai Mountain Eatern China are results from complex interactions between forest ecosystems,topogrphy,and geomorphology.Detecting and quantifying the transitional zones are highly important since high environmental beterogeneity and biodiversity are ofter found within these zpmes.In this study,we used GIS and multivariate statistics techniques(PCA and MSWA) to analyze data from Landsat TM satellite imageries and quantitatively determined the positions and widths of the landscape boundary betweeen mountain birch and evergreen coniferous forests in the northern slope of Changbai Mountain.The results showed that the widths of the landscape boundary ranges from 30-50 m while using the MWW A or/and PC method.Such detected widths are consistent with field transect data that suggest a 50m tranistional zone width.The results further suggest that TM data can be used in combination with GIS and statistical techniques in determining forest landscape boundaries.MSWA is more reliable than PCA,while PCA can also be used to determine the landscape boundary when transects are properly located.  相似文献   
109.
本文首先分析了高等职业教育电子技术课程的传统教学方式和弊端,随后探讨了电子技术教学的改革途径:包括高职教材内容的修订和更新,通过多媒体技术与EDA技术改善电子技术的课堂教学;精选验证性实验及强化EDA技术在实验和设计环节中的比例等多方面措施。  相似文献   
110.
HE Yong  |liang    LIN Yu  |huan    {*  }  LI Wen  |cheng   《环境科学学报(英文版)》2000,(Z1)
1 IntroductionThegoldindustryinChinagrowsupquicklywiththegrowthrateofabout 10 %since 90’s.In 1995,theproductionofgoldwasover10 0tons/a,andin 1996reached 12 0tons/a .Itisrankedsixthintheworld(Chang ,1995) .Theirmainproceduresofgoldextractionare :(1)cyanizationintotalore carbo…  相似文献   
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