阳极材料对医院污水电化学消毒处理效果的研究

分析了三维电极法处理医院污水的影响因素，探讨了阳极材料、电流密度．水力停留时间、空气流量、极水比等因素对消毒效果的影响，确定在不加化学药剂、不影响水质和低耗能条件下电化学消毒试验的最佳使用条件。结果表明，在用涂有贵金属（钌、铂、铱）氧化物的钛板作阳极，不锈钢板作阴极，电流密度为6mA／cm^2、水力停留时间为15min、空气流量为40L／h、极水比为1．0的试验条件下，消毒后污水中总大肠菌群数〈500CFU／L。电化学法消毒处理医院污水方法简单有效、运行费用低，无二次污染．处理后的污水达到国家一级排放标准（GB8978—1996）。     

北京市铁路站场大气颗粒物的特征与来源分析

利用扫描电镜-X射线能谱(SEM-EDX)技术对北京市铁路站场采集的颗粒物的形貌和化学组分进行分析,并利用富集因子法及元素相关性对颗粒物中的各元素来源进行判别。研究结果表明,铁路站场所采集的主要是2μm以下的球形或椭球形富含S、Br、Zn元素的颗粒,富集因子及元素相关性分析显示,该颗粒物主要来源于铁路机车燃油排放。因此,确定颗粒物的排放源并以此进行控制,对于改善北京铁路站场周围的大气环境具有重要意义。     

THE COMPARISON BETWEEN SOUTHERN ANDES AND ANTARCTIC PENINSULA A REVIEW, NEW PROGRESS AND PROSPECT

The comparative research of southern Andes and Antarctic Peninsula is a key to explain the break-up of Gondwanaland. "Cuspate" , "Arcuate", "Continuing". "Overlapping" and "Modified Gulf of California" model illustrated, to some extent, southern Andes-Antarctic Peninsula relations. However, those models did not discuss the dynamic mechanism and specific evolution process of the two Plates' divergence. "Wedge" model, on the bases of eight geological evidences including tectono-stratigraphic unit, strike-slip fault system, carthquake, igneous activity and so on, not only discussed southern Andes-Antarctic Peninsula relations and its evolution process, but also presented an argument that Scotia minor-plate, which once acted as one part of Pacific Plate wedged in between the two Plates and gave rise to the break-up of Gondwanaland-The argument represents the the latest achievement made in geological research there. On the whole, all models mentioned-above are, more or less, of one-sided view. Where the dynam     

黄磷尾气现场脱硫试验

黄磷尾气的主要成分是CO，其中含硫杂质主要以硫化氢的形式存在。测定了黄磷尾气中硫化氢、氧气的含量，分别采用吸收、吸附工艺及其组合工艺对黄磷尾气进行了现场脱硫试验，得出了最佳的黄磷尾气净化脱硫工艺，即吸收、活性炭变温吸附。出口气中H2s的质量浓度为1—5mg/m^3，净化效率达到99．7％。     

亭子口库区水质汞的污染特征及建库后水体中汞的预测

亭子口水利枢纽位于喜陵江平流苍溪县城以上，１５ｋｍ处。本文根据嘉陵江广元段水质监测资料，分析库区地面水体中汞的现状污染特征，并运用沉积物的负指数方程预测库区建坝后水体中汞的浓度。     

跨越劳动合同终止日期的医疗期满后劳动合同不能自动终止

赵某于2002年9月应聘到甲公司工作,双方未签订劳动合同.2003年1月1日双方签订了为期1年的劳动合同,约定月工资为1700元,劳动合同终止时间为2003年12月31日.     

重庆市建设工程从业人员现状调查与对比分析

对重庆市106家工程建设单位的从业人员的现状的调查情况进行了分析,发现其在年龄结构、学历结构、职称结构等方面存在的问题,并针对出现的问题提出了改进的建议.     

美国油气开发钻井废物排放管理法规浅析

钻井是石油天然气勘探开发过程中的重要环节,钻井过程中污染物的排放管理也受到各国普遍的重视。对钻井污染物的特点进行了分析,在此基础上概括地介绍了美国的相关环境管理法规体系。重点论述了与钻井排污有关的资源保护与补偿法、安全饮用水法、清洁水法等,总结了可供我国借鉴的若干法规、标准制定的理念和方法。     

Using ecological memory as an indicator to monitor the ecological restoration of four forest plantations in subtropical China

A large area of plantations has been established worldwide and especially in China. Evaluating the restoration status of these plantations is essential for their long-term management. Based on our previous work, we used an ecological memory (EM) approach to evaluate four 26-year-old plantations that represent four common kinds of plantations in subtropical China, i.e., mixed broad-leaved plantation (MBP), mixed coniferous plantation (MCP), eucalyptus plantation (EP), and mixed legume plantation (MLP). Comparing them with the regional climax community, i.e., monsoon evergreen broad-leaved forest (BF), all four plantations accumulated nearly the same pattern of EM during succession. EM was >50 % for soil minerals, light conditions, soil age, soil animals, and soil microbes. EM was about 25 % for soil pollen and 10 % for birds, soil seed bank, and plant species. The total EM value of the four plantations ranged from 50.96 to 52.54, which indicated that all four plantations were in the regional, natural trajectory of succession and between the early and medium successional stages. The results indicated that natural succession processes are unlikely to be accelerated by planting late-stage tree species without sufficient EM. The results also demonstrated that all four plantations were in positive successional trajectories, and the positive succession dynamics were greater in the MLP and MCP. We suggest that the entire natural succession trajectory be used to evaluate the restoration of a site and that the ultimate restoration target be divided into several milestones along the reference trajectory to monitor progress. Forest restoration may be accelerated by starting with a minimum dynamic unit supporting sufficient EM.     

Fluctuating asymmetry rather than oxidative stress in <Emphasis Type="Italic">Bufo raddei</Emphasis> can be an accurate indicator of environmental pollution induced by heavy metals

Oxidative stress (OS) and fluctuating asymmetry (FA) as risk markers for environmental stress are widely used to predict changes in the health and fitness of many animals exposed to pollutants. However, from the perspective of protecting declining amphibians, it remains to be verified which one would be a reliable indicator for amphibians exposed to long-term heavy metal pollution under natural conditions. In this study, the OS and FA of Bufo raddei exposed to natural heavy metal pollution were analyzed to determine which marker is more accurate for indicating heavy metal-induced stress. Three years of data were collected during the breeding season of B. raddei from Baiyin (BY), which has been mainly contaminated with Cu, Zn, Pb, and Cd compounds for a long period, and from Liujiaxia (LJX), which is a relatively unpolluted area. Unexpectedly, although significant accumulation of the four heavy metals was found in the kidney and liver of B. raddei from BY, the levels of superoxide dismutase, glutathione peroxidase, and malondialdehyde in these two organs were found to be irregular, with low repeatability in both BY and LJX. However, significant differences in the levels of FA were observed in B. raddei populations from these two areas over the past 3 years (P < 0.01). The degrees of FA in B. raddei populations from BY and LJX were assessed as degree 4 and 1, respectively. In short, this study suggested that FA was a more reliable and effective indicator than OS to monitor and predict long-term environmental stress on anuran amphibians.