三江平原典型湿地流域水文情势变化过程及其影响因素分析

湿地在流域中由于特殊的水理性质和地理位置而具有特殊的水文调节功能。但是流域水土资源的开发利用常常导致大量湿地丧失和退化,湿地水文调节功能遭到破坏。论文选择三江平原典型湿地流域为案例,详细分析了流域自20世纪60年代湿地开发以来河流流量的变化过程及其主要影响因素。结果显示,流域年均流量在1965～1999年间呈持续下降趋势,但在不同的季节月均流量、最大和最小流量变化出现差异,最小和最大流量向极端化方向发展。进一步分析主要影响因素发现,下垫面条件变化和水利工程对年均径流和流量的影响分别占76%和16%;而降水和水利工程用水对春季径流量减少的影响分别占47%和56%;下垫面条件改变和水利工程排水对秋季径流量增加、流量增大的影响分别占52%和37%。     

污染土壤中重金属的优势流迁移

用亮蓝溶液染色鉴定了2个污染土壤的优势流途径,并分离和采集被染色剂染色和不染色的土样,分析了重金属(Cu,Pb,Cd)含量和形态．结果表明,心土层以下染色部分土壤的重金属含量明显高于不染色部分土壤．两之间的差异随土壤污染程度的增加而增加．染色部分土壤中酸溶态和有机质结合态重金属的比例明显高于不染色部分的土壤．染色部分土壤的细粘粒与粘粒总量的比值也高于非染色部分土壤,但供试土壤的水溶性重金属含量很低,推测颗粒态重金属的迁移是重金属迁移的主要方式,优势流可能在土壤重金属垂直迁移中有重要的作用．     

Determination of arsenic in air particulates and diesel exhaust particulates by spectrophotometry

A method was developed for the determination of trace arsenic by spectrophotometry. The proposed method is rapid, simple,and inexpensive. This method can be used for sensitive determination of trace arsenic in environmental samples and especially in air particulates. The results obtained by this method as a proposed method were compared with those obtained by hydride generation atomic absorption spectrometry as a popular reported method for the determination of arsenic and an excellent agreement was found between them. The method was also used for determination of arsenic associated with airborne particulate matter and diesel exhaust particulates.The results showed that considerable amount of arsenic are associated with diesel engine particulates. The variation in concentration of arsenic was also investigated. The atmospheric concentration of arsenic was different in different sampling stations was dependent to the traffic density.     

阻抑动力学光度法测定痕量邻二硝基苯

研究发现,在盐酸介质中,痕量邻二硝基苯能灵敏地阻抑溴酸钾氧化甲基红褪色的反应。研究了该阻抑褪色反应的最佳条件,建立了一种测定痕量邻二硝基苯的新方法。该方法线性范围为0.0～0.16μg,检测限为1.15×10-10gmL。用于环境水样中邻二硝基苯的测定,结果满意。     

船舶螺旋桨射流扰动下的污染底泥起悬研究

河流、湖泊中船舶的航行对于水体底部的污染沉积物具有很强的扰动作用,特别是船舶尾部的螺旋桨射流。通过一个新近提出的射流速度分布统一公式,结合考虑底泥的起动、冲刷特性,进行船舶螺旋桨射流扰动下污染底泥起悬的计算研究。结果表明,螺旋桨距河流底面的深度、螺旋桨射流出口流速、螺旋桨直径对底部流速的分布影响显著;同时发现,周围水体流动方向及流速等对于底泥扰动范围也有显著影响;最后定量计算了螺旋桨作用下污染底泥扰动悬浮速率。     

微环境新风量的检测原理及方法研究

新风量是评价室内微环境空气卫生质量的主要卫生指标之一,也是计算室内某种气体单位时间排放量的重要参数。以CO2作为示踪气体,利用于冰升华和人体呼吸产生CO2示踪气体两种测量方法对室内和车内微环境进行了检测,并考虑室内人呼出CO2量的影响,运用箱子模式的各种推导公式（稳态法、解析解法和差分法）对新风量进行了计算,并对结果进行了讨论。结果表明,没有人存在下,用箱子模式的解析解法和差分法计算的新风量值没有明显的统计差异;微环境内有人时必须考虑人释放的影响,这样箱子模式的各种推导公式都可以计算新风量值,且结果准确,准确度高。利用人体呼吸产生CO2示踪气体法,用差分法计算结果不理想,偏差很大;用稳态法计算重现性高,结果可靠。     

新型BOD微生物传感流动注射检测仪的研制

研制采用微生物传感技术和流动分析技术来快速测定BOD的仪器。主要技术性能:测量周期为15min;误差率<5%;偏差<5%。通过对国家标准样品和不同水质污水的测试表明,其具有自动化程度高,测量周期短的优点;准确度、稳定性均达到国家标准;且具有良好的适应性。     

分段流动分析法测定水中总氰化物

水样预蒸馏后,经分段流动分析仪自动进样器进入分析模块对水中的总氰化物进行分析。通过试验,确定了最佳测定参数,方法检测限为0 002mg/L,对高低两个不同浓度的标准样品分析,测定值均在其保证值范围内,相对标准差<2 %,准确度和精密度均较好。循环周期约70s,每小时可测定50个样品,分析速度快,尤适于大批量样品的测定。     

Time-series product and substance flow analyses of end-of-life electrical and electronic equipment in China

Given the amounts of end-of-life electrical and electronic equipment (EoL-EEE) being generated and their contents of both harmful and valuable materials, the EoL-EEE issue should be regarded not only as an emerging environmental problem but also as a resource management strategy in China. At present, in order to provide the basis for managing EoL-EEE at both product and substance levels in China, it is necessary to carry out a quantitative analysis on EoL-EEE and to determine how much of it will be generated and how much materials and substances it contains. In this study, the possession and obsolescence amounts of five types of household appliance (HA) including television (TV) sets and the amounts of substances contained in EoL TV sets were estimated using time-series product flow analysis (PFA) and substance flow analysis (SFA). The results of PFA indicated that the total possession amounts of those five types of HAs will exceed 3.1 billion units in 2030, which will be two times higher than those in 2010. In addition, it was estimated that cumulatively over 4.8–5.1 billion units of these five types of EoL HA would be obsoleted between 2010–2030. The results of SFA on TV sets indicated that the generated amounts of most of the less common metals and a part of common metals such as copper (Cu) would tend to decrease, whereas those of other common metals such as iron (Fe) as well as precious metals would tend to increase in EoL TV sets in 2015–2030. The results of this study provide a quantitative basis for helping decision makers develop strategic policies for the management of EoL-EEE considering both environmental and resource aspects. Moreover, a calculation scheme of obsolete HAs presented in this study can be applied to estimate other types of EoL durable good. Meanwhile, the frameworks of this study will help not only the policy decision makers in the Chinese government but also those in developing countries that are facing similar problems.     

动量探头对流化床中簇团运动特性的研究

在很多工业生产过程的气固两相流动中,固体颗粒多以簇团的形式存在,而在目前已投产运行的流化床设备中,能够有效获取床内簇团特性的设备尚较少见。使用动量探头在一循环流化床锅炉冷态试验台上,以玻璃微珠为床料,采集了炉内不同空间位置不同工况下的簇团压力波动信号,并对信号进行滤波处理,得到相应周期内的簇团频率。通过试验证实了基于簇团频率测量的动量探头能够有效获取炉内簇团运动特性,从而了解床内流化状态的改变、床内磨损状态、床内物料量变化等信息。该方法正确反映了炉内工况的变化,并可直接用于实炉热态测量,为设备安全稳定运行提供了参考。