QSARs for the toxicity of polychlorinated dibenzofurans through DFT-calculated descriptors of polarizabilities, hyperpolarizabilities and hyper-order electric moments

DFT-B3LYP method with 6-31G(**) basis set was employed to fully optimize the electronic structures of 135 polychlorinated dibenzofurans and parent compound, namely dibenzofuran. It was demonstrated that polarizability anisotropy and mean polarizability could change sensitively and systematically with chlorine number and substitution pattern. And new quantitative structure-activity relationships (QSARs) focused on the binding affinities of aryl hydrocarbon receptor (AhR), aryl hydrocarbon hydroxylase (AHH) and 7-ethoxyresorufin O-deethylase (EROD) induction potencies of PCDFs were developed. It was concluded that polarizability anisotropy in conjunction with hyperpolarizabilties and hyper-order electric moments, e.g. octupole moments could well interpret the variation of toxicity of different congeners and dispersion interaction should be the leading form among various interactions. Although the terms of hyperpolarizabilities and hyper-order electric moments were not the same significant ones as polarizability anisotropy, the long-range interactions characterized by them should not be ignored in explaining the toxicity.     

Ambient air monitoring of PCDD/Fs and co-PCBs in Gyeonggi-do, Korea

We started the monitoring for PCDD/Fs in ambient air and soil in August 2001, and co-PCBs in January 2002. Decreasing of PCDD/Fs and co-PCBs levels in ambient air were observed. The higher PCDD/Fs levels were found in winter and lower in autumn. We found that the industrial incinerators influenced the PCDD/Fs levels in ambient air. In the 2,3,7,8-substituted PCDD/Fs concentration profiles, the three major congeners occupied 67% of the total mass. In case of co-PCBs, PCB#118, #105 and #77 were observed as the main congeners. Five cluster groups discriminated by ratio of four components, O(8)CDD, 1,2,3,4,6,7,8-H(7)CDD, 1,2,3,4,6,7,8-H(7)CDF and O(8)CDF, were obtained from HCA (hierarchical cluster analysis).     

光污染的危害与防护措施

光污染已经成为继水污染、大气污染、噪声污染、固体废物污染之后的第五大污染．是21世纪直接影响人类健康的又一环境杀手!     

再生白土无污染生产技术的研究

用低浓度的废酸水对废白土进行活化,并采用洗涤水循环漂洗的方法,对再生白土无污染生产技术进行研究,以期循环利用废白土,保护环境,节约资源。结果表明：废酸水浓度为15％,固液比1：3,酸化时间3h时,再生白土脱色率为98．0％。     

影响马尾松毛虫虫灾发生类型因素的重要性分析

运用列联表分析方法探讨了小班的林地起源、优势树种、地理、生长等因素对小班的马尾松毛虫虫灾发生类型的影响。分析结果表明：小班的海拔高度和坡度是决定小班的马尾松虫灾发生类型的关键因素。小班的优势种结构、平均树高及郁闭度对小班的马尾松毛虫虫灾发生类型也有较大的影响。图12表1参2     

接种Glomus versiforme对红三叶草利用有机磷的影响

以红三叶草为材料,利用三室隔网培养方法,研究接种菌根真菌Glmous versiforme对土壤有机磷及外加有机磷化合物植酸钠（Na-Phytate)、核糖核酸（RNA）和卵磷脂（Lecithin)的利用效率,植株生长7wk后收获测定植标干物重、含磷量和根系菌根侵染率,结果表明：接种菌根真菌能明显增加植株干物重、含磷量和吸磷总量,与各有机磷处理相比,无机磷（KH2PO4）处理生长效应最好,施用有机磷化合物各处理与CK相比均明显促进了植株生长,但不同有机磷处理之间没有显著差异,在植株吸磷量上,各接种处理均为相应CK处理的2倍以上,其中磷酸二氢钾处理吸磷量最高,菌根对照植物的根外菌丝虽然被限制在有限的空间内,但其吸磷量也达到不施磷的CK－M处理的2倍多,这说明由于菌根的形成植物能利用土壤因有的有机磷来满足自身生长的需要,表3参10     

循环流化床锅炉烟气脱硫除尘技术改造

对承德市热电厂CG35／3．82－MX型循环流化术锅炉的脱硫除尘系统进行了改造,解决了原水膜除尘器效率低,烟法排放严重超标的问题,取得了良好的环境效益,社会效益和经济效益。     

Contamination of marine fauna by chlordecone in Guadeloupe: evidence of a seaward decreasing gradient

Chlordecone is an organochlorine pesticide, used in the Lesser Antilles from 1972 to 1993 to fight against a banana weevil. That molecule is very persistent in the natural environment and ends up in the sea with runoff waters. The objective of the present study is to evaluate the level of contamination in several trophic groups of marine animals according to their distance from the source of pollution. Samples of suspended matter, macroalgae, herbivorous fishes, detrivorous crustaceans, zooplanktivorous fishes, first- and second-order of carnivorous fishes, and piscivorous fishes have been collected in two sites, located downstream the contaminated sites (Goyave and Petit-Bourg), in three marine habitats (coastal mangroves, seagrass beds located 1.5 km from the shoreline, and coral reefs at 3 km offshore). Animals collected in mangroves were the most contaminated (mean concentrations 193 μg kg^?1 in Goyave and 213 μg kg^?1 in Petit-Bourg). Samples from seagrass beds presented intermediate concentrations of chlordecone (85 μg kg^?1 in Goyave and 107 μg kg^?1 in Petit-Bourg). Finally, samples from coral reefs were the less contaminated (71 μg kg^?1 in Goyave and 74 μg kg^?1 in Petit-Bourg). Reef samples, collected 3 km offshore, were two to three times less contaminated than those collected in mangroves.     

Development and implementation of eco-genomic tools for aquatic ecosystem biomonitoring: the SYNAQUA French-Swiss program

The effectiveness of environmental protection measures is based on the early identification and diagnosis of anthropogenic pressures. Similarly, restoration actions require precise monitoring of changes in the ecological quality of ecosystems, in order to highlight their effectiveness. Monitoring the ecological quality relies on bioindicators, which are organisms revealing the pressures exerted on the environment through the composition of their communities. Their implementation, based on the morphological identification of species, is expensive because it requires time and experts in taxonomy. Recent genomic tools should provide access to reliable and high-throughput environmental monitoring by directly inferring the composition of bioindicators’ communities from their DNA (metabarcoding). The French-Swiss program SYNAQUA (INTERREG France-Switzerland 2017–2019) proposes to use and validate the tools of environmental genomic for biomonitoring and aims ultimately at their implementation in the regulatory bio-surveillance. SYNAQUA will test the metabarcoding approach focusing on two bioindicators, diatoms, and aquatic oligochaetes, which are used in freshwater biomonitoring in France and Switzerland. To go towards the renewal of current biomonitoring practices, SYNAQUA will (1) bring together different actors: scientists, environmental managers, consulting firms, and biotechnological companies, (2) apply this approach on a large scale to demonstrate its relevance, (3) propose robust and reliable tools, and (4) raise public awareness and train the various actors likely to use these new tools. Biomonitoring approaches based on such environmental genomic tools should address the European need for reliable, higher-throughput monitoring to improve the protection of aquatic environments under multiple pressures, guide their restoration, and follow their evolution.     

四氨基酞菁钯/γ-Al_2O_3可见光催化降解罗丹明B

采用浸渍法制备了四氨基酞菁钯(PdTAPc)/γ-Al_2O_3负载型光催化剂,采用UV-Vis,FTIR,XRD,SEM技术对其进行了表征,并将其用于罗丹明B的可见光催化降解,考察了光催化剂加入量、溶液pH、H_2O_2加入量、反应温度对罗丹明B降解效果的影响,并对光催化剂的稳定性进行了测试。表征结果显示,PdTAPc以圆片状负载于γ-Al_2O_3上,二者的结构均未发生明显变化。实验结果表明:在光催化剂加入量1.6 g/L、溶液pH 7.0、H_2O_2加入量12 mmol/L、反应温度20℃的优化条件下反应120 min,罗丹明B(质量浓度0.05 g/L)的降解率高达95%;光催化剂具有较高的稳定性,使用4次后罗丹明B的降解率仍高于85%。