稀土作业者外周血淋巴细胞姊妹染色单体互换的观察

本文报告了 5 0例稀土作业工人外周血淋巴细胞姊妹染色单体互换 (SCE)的观察结果 ,其 SCE频率为 5 .49± 1.2 1(SCE/ cell,X SE) ,与 2 0例对照组相比 ,差异显莉 (P<0 .0 1)。随工令的延长 ,SCE频率为增高的趋势 ,但各工令组之间 ,经统计学处理 ,差异不显著 (P<0 .0 5 )。男工 SCE率高于女工 ,这可能与男工吸烟人数多于女工有前。我们认为 :SCE可作为稀土作业人员早期危害观察指标     

膜生物反应器运行中的膜污染问题

这了各国研究者针对膜生物反应器中的膜污染问题所作的工作，认为膜本身的性质以及废水组成和工艺条件都是造成膜污染的主要原因，利用反冲洗和清洗手段，可以有效地改善膜的性能，以提高膜的寿命，膜生物反应器技术的改进是避免膜污染的新思路。     

特征分析方法优化大气监测布点及MATLAB语言实现

提出了运用特征分析方法优化大气监测布点,并介绍了该方法的MATLAB语言实现过程。应用于大气监测优化布点的实例结果表明,该方法用于监测优化布点是可靠的。     

溶剂萃取--蒸汽蒸馏法处理含油污泥

为了实现含油污泥的资源化和无害化，对含油污泥进行了室温下的三氯甲烷溶剂萃取，然后在温度３２０～４８０℃、压力０．２ＭＰａ下进行水蒸汽蒸馏０～９０ｍｉｎ的掊油实验，结果表明含油污泥中加入３倍的萃取溶剂进行萃取，再按１ｇ油泥加０．５ｍＬ的水在４００℃下蒸馏，４５ｍｉｎ效果较好，脱油率达８０％～９５％。     

Chemical composition of precipitation and its sources in Hangzhou, China

To understand the origin and chemical characteristics of precipitation in Hangzhou, rainwater samples were collected from June 2006 to May 2008. All samples were analyzed for pH, electrical conductivity, and major ions (NH??, Ca2?, Mg2?, Na?, K?, SO?2?, NO??, F?, and Cl?). Acidification of precipitation in Hangzhou was serious with volume-weighted mean pH value of 4.5, while frequency of acid rain was 95%. The calculated SO?2?/NO?? ratio in Hangzhou precipitation was 2.87, which indicated that the precipitation of Hangzhou belonged to sulfate-based acid rain. The results of acid neutralization analysis showed that not all the acidity in the precipitation of Hangzhou was neutralized by alkaline constituents. The results of sea salt contribution analysis showed that nearly all SO?2?, Ca2?, and Mg2? and 33.7% of K? were of non-sea origins, while all Na? and Cl? and 66.3% of K? originated from sea sources. The principal component analysis which was used to analyze the sources of various ions indicated that chemical compositions of precipitation in Hangzhou mainly came from terrestrial sources, factory emissions, fuel wood burning, and marine sources.     

Assessment of elemental distribution and trace element contamination in surficial wetland sediments, Southern Tibetan Plateau

In order to analyze and evaluate different trace metals on surface water of the Changjiang River, concentrations of dissolved trace metals (Cu, Ni, Fe, Co, Sc, Al, Zn, Pb, Cd, Se, As, Cr, and Hg), major elements(Ca and Mg), and nutrient(NO $_{3}^{-})$ were measured. Samples were taken at 76 positions along Changjiang River in flood and dry seasons during 2007?C2008. Spatial distributions identified two main large zones mainly influenced by mineral erosion (sites 1?C22) and anthropogenic action (sites 23?C76), respectively. Principal component analysis (PCA) and hierarchical cluster analysis were used to identify the variance distinguishing the origin of water. Four significant components were extracted by PCA, explaining 74.91% of total variable. Cu, Ni, Fe, Co, Sc, Al, Ca, and Mg were mainly associated with the weathering and erosion of various rocks and minerals, while an anthropogenic source was identified for Cd and As. Although erosion was one source of Pb and Zn, they were also input by atmospheric deposition and industrial pollutions. NO $_{3}^{-}$ and Se were mainly associated with agriculture activities. However, Hg and Cr showed different sources. CA confirmed and completed the results obtained by PCA, classifying the data into two large groups representing different areas. Group 1 referred to the upper reaches which represented samples mainly corresponding to natural background areas. Group 2 referred to the middle and lower reaches including samples under anthropogenic influence. Meanwhile, group 2 was subdivided into three new groups, representing agricultural, industrial, and various artificial pollution sources, respectively.     

内分泌扰乱化学品对动物的影响和作用机制

介绍了内分泌扰乱化学品(EDCs)的作用机制及其对野生动物影响的研究进展。内分泌化学品可能与性激素受体、甲状腺素受体和其他受体(如芳烃受体)结合,也可能通过影响动物体内激素的代谢而对动物的生长发育起调控作用。各实验室的重复实验不支持环境雌激素之间存在协同作用的结论。已报道过的人体和野生动物生殖缺陷中具有充分证据的暴露-效应关系的实例为数不多。尽管野生鱼类变性是英国河流中的一个普遍现象,但进一步的实验证明污水处理场出水中的天然和合成雌激素足以引起鱼类的变性反应,而不是先前怀疑的非离子表面活性剂降解产物。目前尚不能对EDCs对人体和野生动物的健康风险作出正确评价,并有待于进一步研究。      

成矿作用中金银的共生与分离及Au/Ag比值的校正

在内生作用中金与银既有共生的一面 ,又有分离的一面。其共生与分离受地球演化历史制约 ,受控于元素化学性质和地球化学亲和性 ,与岩浆起源、演化有关 ,受控于不同的基底建造和构造单元。成矿作用中金与银的共生与分离可用Au/Ag比值大小来衡量 ,本文提出了根据Au、Ag的地壳克拉克值和工业品位对传统的Au/Ag比值进行校正的方法 ,校正后的Au/Ag比值可有助于矿床研究、找矿预测和资源评价等工作     

遥感调查方法在河北省省级自然保护区生态环境变化评估方面的应用研究

河北省省级自然保护区以自然生态系统类型为主,人类活动较为频繁,将遥感评估方法应用于河北省省级自然保护区生态环境变化评估具有重要意义。本文通过分析高分辨率遥感卫星影像的特点,结合河北省省级自然保护区的实际情况,优先选取分辨率为2m的民用卫星,提出了遥感调查方法在自然保护区人类活动和开发建设活动中自动监测、生态系统格局变化、生态系统质量变化以及人类活动干扰程度四方面的评估应用。     

油料作物对土壤老化残留DDT的吸收积累

油料作物对亲脂性DDT的吸收富集能力是否会更强是一个值得研究的问题。采用DDT老化残留土壤,温室盆栽油料作物花生(Arachishypogaea),大豆(Glycinemax)和芝麻(Sesamumindicum)。果实成熟后将植株分成根、茎、果壳和果仁四部分,GC-ECD测定各部位中的DDT浓度。研究了油料作物对土壤老化残留DDT的吸收积累情况,结果表明,∑DDT在三种作物不同部位中的浓度顺序都是:根>茎>果壳>果仁。含油量高的花生果仁和芝麻果仁中∑DDT浓度都明显高于大豆果仁的∑DDT浓度,这种差异有可能是由果仁含油量的差异造成的。单株植物吸收积累∑DDT的总量顺序为:花生>芝麻>大豆。花生、大豆和芝麻三种作物的根和茎的生物富集系数都比较高,特别是花生的,说明这三种油料作物根部从土壤中吸收积累老化残留DDT的能力以及从根部向茎部运输DDT的能力都是相当强的。