Organochlorine pesticides in the surface water and sediments from the Peacock River Drainage Basin in Xinjiang, China: a study of an arid zone in Central Asia

Fourteen surface water and nine surface sediment samples were collected from the Peacock River and analyzed for organochlorine pesticides (OCPs) by gas chromatograph?Celectron capture detector (GC-ECD). All the analyzed organochlorine pesticides, except o,p ^??-DDT, were detected in sediments from the Peacock River; but in the water samples, only ??-HCH, HCB, p,p ^??-DDD, and p,p ^??-DDT were detected at some sites. The ranges for total OCPs in the water and sediments were from N.D. to 195 ng l^???1 and from 1.36 to 24.60 ng g^???1, respectively. The only existing HCH isomer in the water, ??-HCH, suggested that the contamination by HCHs could be attributed to erosion of the weathered agricultural soils containing HCHs compounds. Composition analyses showed that no technical HCH, technical DDT, technical chlordanes, endosulfans, and HCB had been recently used in this region. However, there was new input of ??-HCH (lindane) into the Peacock River. The most probable source was water flowing from Bosten Lake and/or agricultural tailing water that was returned directly into the Peacock River. DDT compounds in the sediments may be derived mainly from DDT-treated aged and weathered agricultural soils, the degradation condition was aerobic and the main product was DDE. HCB in the sediment might be due to the input from Bosten Lake and the lake may act as an atmospheric deposition zone. There was no significant correlation between the concentrations of OCPs (including ??HCH, ??DDT, chlordanes, endosulfans, HCB and total OCPs) and the content of fine particles (<63 ??m). The concentrations of OCPs were affected by salinity.     

Distribution and chemical partitioning of heavy metals in marine near-shore sediment cores: a case study from the Xugou, Lianyungang, China

The concentrations and chemical partitioning of heavy metals (Co, Cr, Ni, Zn, Cu, and Pb) in the marine near-shore sediment cores were investigated. Typically, the mean concentrations from Core B sediment samples were 98.6, 21.1, 47.0, 46.4, 107.6, and 31.9 mg kg^???1 for Cr, Co, Ni, Cu, Zn, and Pb, respectively. The heavy metal concentrations were normalized to commonly used reference elements Al, Li, Sc, and total organic carbon. Based on Pearson coefficients, Li was found to be a good normalizer for Co (r?= 0.974), Cr (r?= 0.967), Ni (r?= 0.898), and Zn (r?= 0.929) in 80 sediment samples from three sampling sites. However, the correlation coefficients between Li and Cu, and Li and Pb were relatively low. Multivariate statistic approaches (Principal Component Analysis and Cluster Analysis) were adopted for data treatment, allowing the identification of two main factors controlling the heavy metal variability in the sediments. Heavy metals in the enrichment sections were evaluated by a sequential extraction method for possible chemical forms in sediments. The results showed that the residual, Fe/Mn oxides and Organic/sulfide fractions were dominant geochemical phases in the enriched sections, indicating low bioavailability of heavy metals in sediments.     

Fire and Explosion Index calculation method incorporating classified safety measure credits

Based on an analysis of two methods for the modification of the F&EI for the DOW Guide, it is found that the effects of safety measures are not classified. Moreover, the efficiency of the measures is magnified to various degrees, as the positive impact of the loss reduction measures are applied to the rate reduction of the intrinsic hazard in the evaluated unit. For this reason, a modification method using classified safety measures is proposed, in which safety measures are classified into process protection measures and loss reduction measures. The calculation of the modified F&EI involves the credit factors of process protection measures, whereas the determination of the maximum probable property damage incorporates the loss reduction measures. This method could provide more reasonable reference data for hazard units because of its more objective and reasonable evaluation results.     

复杂系统安全涌现及其控制策略研究

复杂系统事故成因的复杂性促使人们从系统科学和复杂性科学的角度来分析和处理复杂系统的安全问题.通过探讨复杂系统可靠性和安全性的关系,论证安全是复杂系统的整体涌现这一论题.通过分析系统安全涌现的内涵,提出用于度量复杂系统风险状态的风险熵理论,给出了复杂系统安全事故立体致因网络的构建方法,并提出了通过控制复杂致因网络上风险熵的动力学传播过程来控制复杂系统安全涌现的研究思路.研究结论对复杂系统安全问题的研究有推动作用.     

数据资源规划在宏观环境督察业务领域应用研究

信息流的畅通和数据资源的有效利用是信息化可持续发展的基础。本文介绍了基于顶层设计的数据资源规划方法,提出数据资源规划的工作步骤。结合宏观环境督察业务现状和业务发展需要,归纳、分析、聚类、抽象出宏观环境督察业务职能域和全域数据元素集,形成了宏观环境督察数据资源的整体规划,为建立宏观督察业务的业务模型和数据模型提供了基础。     

人工湿地技术处理油田含油污水的应用

与传统污水处理工艺相比,人工湿地技术具有高效低耗、运行维护简便、对复杂含油污水净化效果良好等特点。文章综述了人工湿地技术处理油田含油污水的净化机理、净化效果、工艺流程及其工艺优势,为含油污水处理技术的研究提供借鉴和参考,对深入认识人工湿地净化机制亦具有一定意义。     

淮海经济区旅游规模差异及其位序规模体系研究

运用经济地理学中测度区域经济差异的指标,对淮海经济区近10年的入境旅游规模差异进行分析.研究发现,淮海经济区入境旅游规模的绝对差异和相对差异基本上呈逐年上升趋势,区域旅游规模发展差异较大,早期首位分布不明显,但后期表现明显.为进一步探讨淮海经济区入境旅游规模差异的原因,该研究运用城市地理学中的位序—规模法则,通过回归分析对淮海经济区入境旅游规模体系进行研究.结果表明,淮海经济区入境旅游规模符合位序—规模分布,入境旅游规模开始逐渐呈首位型发展,入境旅游规模分散均衡程度低,部分城市存在高度垄断现象.此外,在最后指出了本研究的局限性、不足之处和今后的主要研究方向.     

湖北省森林资源发展问题刍议

湖北省具有发展森林资源的良好条件，但目前的森林覆盖率不高，林种结构不合理，森林生产力相当低。应在保护和经营好现有森林资源的基础上，以扩大森林面积和提高森林质量为中心，统筹规划，合理布局，增加投入，加速发展，科学经营，永续利用，不断提高其经济、社会、生态效益，造福于人民。     

液桥凝聚用于办公废纸脱墨的研究

研究了混合办公废纸脱墨的选择性凝聚技术,在废纸浆中添加分散在水中并不与水相溶的长链烷作凝聚剂,这些凝聚剂选择性地将印刷墨粉通过液桥连结在一起,且形成大颗粒的球形聚团,再分选脱除.研究表明只需要加入占纸重量4%的廉价长链烷,即可获得95%以上的脱墨率.因此在混合办公废纸脱墨时加入凝聚剂进行液桥凝聚,可降低脱墨浆中的尘埃度并增加产品的白度.     

乌鲁木齐市烟尘控制区验收监测结果分析

通过对验收监测结果的分析，找出了乌鲁木齐市烟尘控制区的烟尘排放特点并提出了相应的建议。