岩溶区地下水位下降致塌的数值模拟研究

文章运用三维数值模拟的方法对复杂的岩溶塌陷机理及过程进行了系统性研究,探讨了Flac3D三维数值模拟应用于岩溶塌陷的模拟技术及方法,为岩溶塌陷的客观评价及预测开辟了有效途径。在研究中成功地应用数值模拟的方法时地下水面以上的土洞塌陷机制进行了模拟,并对岩溶区的典型地质概化模型的致塌机理进行验证。     

固相反射散射分光光度法测定化妆品中的铅

在酸性条件下 ,铅 ( )与玫瑰红酸钠形成紫红色络合物沉淀 ,该沉淀能被均匀地抽滤到一定表面积的滤纸上。本文采用固相反射散射分光光度法直接测定滤纸上负载的络合物的反射吸收值 AR,铅的含量在 0～ 8μg/ m L的范围内 AR与浓度有良好的线性关系。方法简便、快速 ,检出限为 0 .0 5μg/ m L。相对标准偏差为3.0 %。方法用于化妆品中铅的测定 ,结果令人满意     

光纤传输在地震台信号传输中的应用

深圳地震台处于强雷电干扰地区，雷电干扰的破坏给深圳地震台的各类设备带来严重的损害，造成较大的经济损失，后来在信号传输线路上改用了光纤传输，起到了明显的效果。作者将深圳台在应用光纤传输地震信号的实践工作进行简要总结，供一线台站的同行参考。     

隧道围岩应变非线性回归分析

本文以小岩头隧道为依托,根据监控工作的实测资料,按照新奥法基本原理中岩体开挖的时间效应,应用数学的方法对量测所得的净空收敛数据进行回归分析,指出在隧道开挖过程中围岩变形的时间效应,为修改设计与指导施工提供理论依据。     

废水中染料的TiO_2光催化氧化降解机理研究现状

系统论述了废水中TiO2光催化氧化降解染料的机理、动力学机制、染料的反应活性、研究中间降解产物的方法和结果等的研究现状,指出了目前研究中最大难点是分析手段的不足,对此提出了自己的看法,这为今后实际废水处理工艺过程中起到指导控制作用。     

Vertical distribution of polycyclic aromatic hydrocarbons in atmospheric boundary layer of Beijing in winter

Air samples were collected using active samplers at various heights of 8, 15, 32, 47, 65, 80, 102, 120, 140, 160, 180, 200, 240, 280 and 320 m on a meteorological tower in an urban area of Beijing in two campaigns in winter 2006. Altitudinal distributions of polycyclic aromatic hydrocarbons (PAHs) in atmospheric boundary layer of Beijing in winter season were investigated. Meteorological conditions during the studied period were characterized by online measurements of four meteorological parameters as well as trajectory calculation. The mean total concentrations of 15 PAHs except naphthalene of gaseous and particulate phase were 667±450 and 331±144 ng m⁻³ in January and 61±19 and 29±6 ng m⁻³ in March, respectively. Domestic coal combustion and vehicle emission were the dominant PAH sources in winter. Although the composition profiles derived from the two campaigns were similar, the concentrations were different by one order of magnitude. The higher concentrations in January were partly caused by higher emission due to colder weather than March. Moreover, weak wind, passing through the city center before the sampling site, picked up more contaminants on the way and provided unfavorable dispersion condition in January. For both campaigns, PAH concentrations decreased with heights because of ground-level emission and unfavorable dispersion conditions in winter. The concentration ratio of PAHs in gas versus solid phases was temperature dependent and negatively correlated to their octanol–air partition coefficients.     

美、日、英、法等国的环境管理体制概况及其对我国的启示

本文简要介绍了美日英法四环境管理体制的状况，分析了四国在环境管理体制建设方面的有益经验及其对我国的启示。     

应用发光菌测定有机化合物的毒性

本文介绍了化合物对发光菌半数抑制发光强度的毒性测定方法，测定了几十种芳烃类化合物的毒性，发现不同取代基或取代位置的芳烃毒性不同，并且对发光菌的毒性与对黑呆头鱼的毒性有相关性。     

水利工程建设施工班组安全氛围量表研究

为有效提高水利工程建设的安全管理能力,基于SHEL(软件、硬件、环境、人员)模型,从4个角度划分出7个维度,设计了水利工程建设施工班组安全氛围量表;对湖南省湘江流域数个大型航电枢纽项目的各施工班组的工人进行问卷调研,并利用相关软件分析所收集的数据,采用探索性因子分析法确定安全氛围的维度.结果 表明:水利工程建设施工班组安全氛围的主要影响因素包括安全制度建设、设备设施管理、安全教育考核、事故预防与处理、人员沟通与态度5个方面;该量表从施工班组的角度出发,对安全氛围进行有效测量,可为水利建设单位的安全管理工作提供依据,提高安全管理水平.     

Improvement of detection method of Cryptosporidium and Giardia in reclaimed water

Cryptosporidium and Giardia are two typical species of pathogenic protozoans that seriously endanger water quality. Previous works indicated that detection of Cryptosporidium and Giardia with modified United States Environmental Protection Agency (USEPA) method-1623 using a membrane filtration-elution for sample concentration attained better recovery and lower cost compared to the USEPA method-1623. Several improvements of membrane filtration-elution step as well as immunomagnetic separation (IMS) steps were investigated and an optimized method for detection of Cryptosporidium and Giardia in wastewater reclamation system was recommended in this paper. The experimental results show that an overnight soak of the membrane after scraping and vortex agitation before elution could enhance and stabilize the recovery. Increasing turbidity to 4 NTU by adding kaolin clay before filtration could effectively improve the recovery of low-turbidity water. Washing the concentrate after centrifugation and twice acid dissociation both reduced the impact of water quality to protozoan recovery. Protozoans in different water samples were determined by this optimized method, and the recovery of Cryptosporidium and Giardia were above 70% and 80% respectively, much higher than the acceptance of method-1623. __________ Translated from Environmental Science, 2006, 27(12): 2547–2552 [译自: 环境科学]