Physicochemical substance properties as indicators for unreliable exposure in microplate-based bioassays

In the last years many efforts were made to transform standardized algal test protocols into low-cost microplate assays. While advantages were pointed out frequently, limitations are not systematically addressed, thus hindering a widespread utilisation. In this study a group of organic substances with a wide distribution of volatility (log K_AW from −6.53 to −2.13) and lipophilicity (log K_OW from 1.26 to 4.92) was investigated with respect to the influence of these physicochemical properties on their algal toxicity in different assays. Therefore the EC₅₀ values were determined with a microplate assay based on ISO 8692 protocol and the results were compared with those of an established algal growth inhibition test conducted in air tight glass vessels. Using the ratio of the EC₅₀ values, a clear connection between biological response and volatility as well as lipophilicity of test substances could be detected. Chemicals with a log K_OW higher than 3 or a Henry coefficient log K_AW higher than −4 were identified as less effective in the microplate assay than in the comparative assay. The loss in nominal concentration due to physicochemical properties could be shown to contribute to this using HPLC analysis. Consequently, when using microplate assay’s one should be aware that lipophilic and volatile chemicals might be underestimated in their toxicity, which could be indicated from evaluating related physicochemical properties modelled from structural information prior to an experimental investigation.     

半干法烟气脱硫除尘多级功能处理装置技术与应用

文中介绍了一种炉窑烟气调质、烟气除尘、烟气脱硫在一个单体结构中的一体化装置和在烟气除尘脱硫技术上的应用,并对该脱硫除尘装置与传统的半干法烟气脱硫除尘装置进行了比较。     

城市污水石灰法深度处理工艺中有毒物质的变化规律

分别采用7-乙氧基异酚恶唑酮．脱乙基酶（EROD）活性测定法，重组人激素受体基因的酵母测试和Q67发光菌试验方法，对北京市某生活污水处理厂的进水、二沉出水以及经过石灰法深度处理后的出水中的类二恶英物质、类雌激素物质和急性毒性物质进行了分析。进水中的三类生物毒性效应物质中的急性毒性物质，可通过活性污泥法基本去除，而对类雌激素物质和类二恶英物质的去除率分别为76％和52％。经过石灰沉淀法的深度处理后，可使上述两类物质的总去除率达到95％和68％。出水中的雌激素当量水平与欧洲国家污水处理厂出水水平相当，而类二恶英物质的总浓度低于美国EPA饮用水中二恶英的最大允许浓度。展示了生物毒性测试方法在排水生态风险和工艺评价方面的应用潜力。     

带式运输机防尘装置的研究设计与应用

简要介绍带式运输机防尘装置的研究设计和工程应用情况。实际应用结果表明 ,该装置能长期有效地控制带式运输机尘源 ,便于工人操作和维护检修 ,并可使排风量平均降低 5 0 %以上 ,大大节省了一次投资、运行费和维护管理费 ,是一项值得推广的实用技术     

简单实用安全驱动电路的设计

本文通过对CCD驱动信号的分析，设计出一种简单实用的安全CCD驱动电路，它既不需要设计同步电呼，又可方便地与计算机相连，具有安全，简单，廉价，体积小等特点。     

Comparison of ecotoxicological and physico-chemical data by use of multivariate analyses and graphical displays

Bioassays allow the appreciation of the toxicity of complex effluents, which is difficult to characterize by the sole measurement of some physico-chemical parameters. We have developed a macroinvertebrate multi-test (M.M.T.) with species characteristic of different trophic levels in order to appreciate the ecotoxicological impact of various effluents (especially landfill leachates) and chemicals on aquatic environments. Our aim was: (i) to compare the sensitivity of the macroinvertebrates among themselves and with regard to those of three standard bioassays; (ii) to characterize the effluents according to their toxicity on one hand and according to their physico-chemical composition on the other hand; (iii) to search for possible correlations between the physico-chemical composition of an effluent and its toxicity. In order to achieve these objectives we used first a combination of graphical displays of the raw data, and secondly multivariate analyses: clustering techniques and scaling (ordination) techniques (Principal Components Analysis).     

粉纹夜蛾颗粒体病毒全长增效基因在大肠杆菌中的表达

利用PCR技术扩增了粉纹夜蛾(Trichoplusia ni)颗粒体病毒增效基因全长片段,扩增产物用EcoRⅠ/HindⅢ双酶消化,经0.7%低熔点琼脂糖凝胶电泳纯化后插入pRSET-B中,得重组表达质粒pRSET/enhancin;但重组子生长异常,在IPTG诱导下未能明显表达目标蛋白.用PstⅠ/HindⅢ双酶消化pRSET/enhancin,电泳回收2.7kb片段后插入pQE-30中,得重组表达载体pQE/enhancin;在IPTG诱导下于35℃成功表达出分子量(Mr)约为108×103的融合蛋白并命名为P108.初步纯化的P108显示了极显著的增效活性,对棉铃虫核型多角体病毒感染棉铃虫3龄幼虫的7d致死率提高34.03%,LT50缩短1.4d;对苏云金杆菌杀棉铃虫3龄幼虫的72h致死率提高65.96%.图4表2参14     

炮采工作面降尘技术的研究

炮采工作面在生产期间粉尘浓度较大 ,严重危害着生产安全和作业人员的身体健康。详细地介绍了一种炮采工作面喷雾降尘装置的设计应用和降尘效果     

Assessment of source water contamination by estrogenic disrupting compounds in China

Detection of estrogenic disrupting compounds (EDCs) in drinking waters around China has led to rising concerns about health risks associated with these compounds. There is, however, a paucity of studies on the occurrence and identification of the main compounds responsible for this pollution in the source waters. To fill this void, we screened estrogenic activities of 23 source water samples from six main river systems in China, using a recombinant two-hybrid yeast assay. All sample extracts induced significant estrogenic activity, with E2 equivalents (EEQ) of raw water ranging from 0.08 to 2.40 ng/L. Additionally, 16 samples were selected for chemical analysis by gas chromatography-mass spectrometry. The EDCs of most concern, including estrone (E1), 17βup-estradiol (E2), 17αup-ethinylestradiol (EE2), estriol (E3), diethylstilbestrol (DES), estradiol valerate (EV), 4-t-octylphenol (4-t-OP), 4-nonylphenols (4-NP) and bisphenol A (BPA), were determined at concentrations of up to 2.98, 1.07, 2.67, 4.37, 2.52, 1.96, 89.52, 280.19 and 710.65 ng/L, respectively. Causality analysis, involving comparison of EEQ values from yeast assay and chemical analysis identified E2, EE2 and 4-NP as the main responsible compounds, accounting for the whole estrogenic activities (39.74% to 96.68%). The proposed approach using both chemical analysis and yeast assay could be used for the identification and evaluation of EDCs in source waters of China.     

一种海水透明度测量新方法的研究与实现

随着海洋光学探测技术的不断发展,传统的海水透明度测量方法已无法满足当前对海洋环境参数全方位、多角度、动态实时测量的要求.文章依据海水透明度的光度学定义,提出了一种测量海水透明度的新方法,并基于常用的光学器件及测量仪器,设计了一套海水透明度的实时测量装置,介绍了测量装置的安装调节方法.理论分析和实验均表明,该测量装置可以有效实时测量海水透明度.