Heavy metals in maternal and cord blood in Beijing and their efficiency of placental transfer

This study aimed to determine the effect of exposure to heavy metals in pregnant women in Beijing, China. We also evaluated the association of these heavy metals with birth weight and length of newborns. We measured the levels of 10 heavy metals,including lead(Pb), titanium(Ti), manganese(Mn), nickel(Ni), cadmium(Cd), chromium(Cr), antimony(Sb), stannum(Sn), vanadium(V), and arsenic(As), in 156 maternal and cord blood pairs. An inductively coupled plasma mass spectrometry method was used for measurement. Pb, As, Ti, Mn, and Sb showed high detection rates( 50%) in both maternal and cord blood. Fourteen(9%) mothers had blood Pb levels greater than the United States Center for Disease Control allowable threshold limit for children(50 μg/L).In prenatal exposure to these heavy metals, there was no significant association between any heavy metal and birth weight/length. Moreover, we estimated the placental transfer efficiency of each heavy metal, and the median placental transfer efficiency ranged from 49.6%(Ni) to 194%(Mn)(except for Cd and Sn). The level and detection rate of Cd in maternal blood were much higher than that in cord blood, which suggested that Cd had difficulty in passing the placental barrier. Prospective research should focus on the source and risk of heavy metals in non-occupationally exposed pregnant women in Beijing.     

水质监测项目及其测点优化的对应分析

应用对应分析的方法,研究了水质监测项目与测点的相关性;讨论了厦门地区水质监测项目与测点的优化。     

差分光谱仪与传统点式仪器测定环境空气质量对比研究

本文采用差分光谱仪、传统干分析仪测量环境空气质量，对比实验结果表明：二氧化硫、二氧化氮测量结果差别很小、相关性好，具有可比性；臭氧的测量结果差别较大，但相关性好，具有可比性。二氧化硫的测量结果具有一致性；而二氧化氮、臭氧的测量结果则存在一定系统偏差。     

重铬酸钾对方形网纹瑵的毒性研究

研究了在２５℃条件下重铬酸钾对方形网纹涤Ｃｅｒｉｏｄａｐｈｎｉａｑｕａｄｒａｎｇｕｌａ（Ｏ，Ｆ．Ｍｕｌｅｒ）存活、生殖和生长的影响。急性试验求得铬铬酸钾对该僵的２４ｈ和４８ｈＢｃ５０值分别为１．０１７９ｍｇ／Ｌ和０．４１２７ｍｇ／Ｌ；其可信限分别为０．４６９８一１．７１８０ｍｇ／Ｌ和０．１９８０一０．６９８８ｍｇ／Ｌ。慢性试验以存活、生殖和生长为毒性指标，未觉察反应浓度（ＮＯＥＣ）为０．０６２５ｍｇ／Ｌ，最低觉察反应浓度（ＬＯＥＯ）为０．１２５０ｍｇ／Ｌ，其应用系数在０．１５一０．３０之间。流水试验（ＮＯＥＣ）为０．０３１２５ｍｇ／Ｌ，（ＬＯＥＣ）为０．０６２５ｍｇ／Ｌ，其应用系数在０．０８一０．１５之间。结果还表明生长是最敏感的指标。     

辽宁沿岸海洋底栖钩虾类的种类组成与分布

钩虾类不仅是底栖生物群落的重要组成部分，也是近年来沉积物环境质量研究中主要选用的受试生物。本文根据１９７９￣１９９６年在辽宁涡岸采集的底栖钩虾类标本，首次报道了辽宁沿岸海洋底栖钩虾类的种类组成和生态分布。共报道２９种，分别隶属于１０科２２属于其中有１种为中国新记录。该研究结果将对我国海洋底栖钩虾类的区系研究和沉积物毒性受试生物的选择和采集提供一定帮助。     

城市环境噪声测量中布点数的优化研究

应用主成分分析,模糊聚类概念及动态规划方法对环境噪声测量的布点数进行优化研究。所建立的模型试用于厦门市环境噪声布点数的优化研究。     

美达棉纤维挂载生物膜法处理石化废水中油

本文介绍了利用美达棉纤维持载生物摸法处理石化废水中油的试验结果。当废水在柱内停留时间为６．３ｈ，废水中油的处理效果是令人满意的。在同一含停留时间下入流水的ＣＯＤｃｒ从４２０ｍｇ／Ｌ变到１８３２ｍｇ／Ｌ时，出流水的ＣＯＤｃｒ在１６８．５ｍｇ／Ｌ以下。     

湖南省衡阳市丘岗地开发研究报告

本文分析了衡阳市丘岗地的基本概况,提出了丘岗地开发的指导思想和原则,据此,对衡阳市丘岗地开发利用提出了总体规划报告及其保障措施。     

Assessing the carbon balance of circumpolar Arctic tundra using remote sensing and process modeling.

This paper reviews the current status of using remote sensing and process-based modeling approaches to assess the contemporary and future circumpolar carbon balance of Arctic tundra, including the exchange of both carbon dioxide and methane with the atmosphere. Analyses based on remote sensing approaches that use a 20-year data record of satellite data indicate that tundra is greening in the Arctic, suggesting an increase in photosynthetic activity and net primary production. Modeling studies generally simulate a small net carbon sink for the distribution of Arctic tundra, a result that is within the uncertainty range of field-based estimates of net carbon exchange. Applications of process-based approaches for scenarios of future climate change generally indicate net carbon sequestration in Arctic tundra as enhanced vegetation production exceeds simulated increases in decomposition. However, methane emissions are likely to increase dramatically, in response to rising soil temperatures, over the next century. Key uncertainties in the response of Arctic ecosystems to climate change include uncertainties in future fire regimes and uncertainties relating to changes in the soil environment. These include the response of soil decomposition and respiration to warming and deepening of the soil active layer, uncertainties in precipitation and potential soil drying, and distribution of wetlands. While there are numerous uncertainties in the projections of process-based models, they generally indicate that Arctic tundra will be a small sink for carbon over the next century and that methane emissions will increase considerably, which implies that exchange of greenhouse gases between the atmosphere and Arctic tundra ecosystems is likely to contribute to climate warming.     

新型絮凝剂凝集水中染料的研究

本文介绍了新近开发的ＪＡＺ型絮凝剂对水样中活性艳蓝ＫＮ－Ｒ，直接深棕Ｍ，酸性墨水蓝Ｇ，酸生媒介藏青ＡＧＬＯ，直接耐晒蓝Ｂ２ＲＬ，弱酸性黄ＨＧ等代表性染料的凝集效果及其影响因素。酸性墨水蓝的脱色随ｐＨ值增加而增加，其他染料的最佳脱色区从酸性到中性。在染料起始浓度为１００ｍｇ／Ｌ￣５００ｍｇ／Ｌ范围内，酸性媒介藏青的Ｋ值（色度降至８０时絮凝剂投药量对染料的比值）为２左右，其他染料的ｋ值在１．０以下。直