有机组分土-水分配系数的确定(英文)

有机组分的土水分配系数(Kd)是描述有机组分在地下系统中吸附特征的重要参数。同时,它也是物质运移模拟和环境评价中的主要参数之一。影响Kd的因素可概括为三个方面:土壤性质、有机组分本身特征及水相的物理化学性质。一般而言,对于非极性和弱极性有机组分,土壤中的有机质含量(foc )是影响Kd的最主要因素。但是,对于极性有机组分(POCs), 特别是在土壤有机质含量较低的情况下,土壤中矿物的种类和含量、水化学组分特征(pH、离子力等)经常在吸附过程中起重要作用。实验室内测定Kd的方法包括批实验和柱实验方法。批实验法适用于研究Kd较高情况下的吸附。在Kd较低的情况下,如低有机质土壤对极性有机污染物的吸附,土柱色谱法(SCC)是更适宜的选择。另外,可用土柱色谱法快速了解各种因素对吸附过程的影响,并获取详细的吸附和解吸信息。应用土柱色谱法时应当注意非平衡吸附和可能的柱堵塞问题。很多文献中提到结合柱实验和已有的吸附数据来预测土壤有机碳标准化的分配系数Koc(=Kd/foc)。但是,如果没有考虑吸附中特定的作用过程(如矿物吸附),对极性有机组分Koc的预测将会产生很大的误差。在环境评价中,将从一种土壤测定的Koc 应用到不同性质的土壤中,可能会导致错误的认识。在进行室内实验时,应把标准土(如Eurosoi     

基于生态足迹和主体功能分区的县域灾后重建政策研究 ——以2011年东乡“3.2”特大滑坡灾害为例

评价自然灾害前, 区域的生态足迹可了解当地自然生态系统的开发和利用状态, 结合主体功能分区的方法可为灾后重建提供更契合实际的政策建议. 基于合理灾后重建的理念, 从可持续发展的角度分析了2011年甘肃东乡"3.2"滑坡灾害发生前(2010年)县域生态足迹和生态承载力情况, 并根据海拔和坡度对区域进行功能分区. 结果表明: 草地人均生态足迹为0.94 hm², 生态承载供给为0.022 hm², 赤字0.92 hm² , 草地土地类型存在严重的生态赤字, 直接导致整个县域人均生态赤字0.97 hm². 这表明东乡县人民的消费需求超过了自然系统的再生能力, 人类的生产、 生活强度超过了生态系统的承载力, 区域生态系统处于人类的过度开发利用和压力之下. 由于进出口贸易不大, 因此, 东乡县主要是通过消耗自然资本存量来弥补生态承载力的不足. 考虑到东乡县的实际情况, 通过主体功能分区把该区域分为农业发展区、 生态恢复区以及二、 三产业发展区. 其中, 农业发展区面积为838.24 km²; 生态恢复区面积为701.98 km², 包括退耕还林的面积264.84 km²; 二、 三产业发展区面积105.57 km². 最后根据生态足迹和功能分区的计算结果, 结合实际情况提出了未来可持续发展的政策建议.     

ADWR-X型多普勒天气雷达批处理模式地物杂波抑制的研究

以ADWR—X型雷达为背景,重点研究低仰角批处理模式抑制地物杂波的信号处理,比较得出在实际探测环境下批处理模式应用地物杂波滤波的效果优越于低仰角警戒模式和低仰角多普勒模式下的滤波效果,实际应用表明：方法运用到ADWR—X型雷达能实现低仰角批处理模式地物杂波滤波,滤波器对地物杂波的抑制能力达到30—50dB,滤波器对天气回波的衰减小于6dB,每个体扫节约2个cut的时间,约60s。     

王3井、王4井水化学测项数据录入及报表打印程序功能

简要介绍了王3井、王4井水化学测项数据录入及报表打印程序,从DBF数据库的建立、Excel报表模板的建立、程序实现3个方面加以阐述。     

The Effect of Oxygen on Anaerobic Color Removal of Azo Dye in a Sequencing Batch Reactor

In this study, various amounts of oxygen were added to the anaerobic phase of an anaerobic‐aerobic sequencing batch reactor (SBR) receiving azo dye remazol brilliant violet 5R to mimic the input of oxygen into the anaerobic zones of biological textile wastewater treatment plants. The effect of oxygen on the anaerobic biodegradative capability of the mixed microbial culture for remazol brilliant violet 5R was investigated. To investigate the effect of oxygen on anaerobic azo dye biodegradation, the anaerobic phase of the SBR cultures were exposed to a very low limited amount of oxygen for various air flow rates. Initially, an air flow rate of 20 mL/min was applied, further on the air flow rate in the anaerobic phase was increased up to 40 mL/min. System performance was determined by monitoring chemical oxygen demand, color removal rate, activities of anaerobic (azo reductase) and aerobic enzymes (catechol 2,3‐dioxygenase, catechol 1,2‐dioxygenase). The results of percentage COD reduction at each stage were similar for all runs, giving an overall reduction of 96%. Anaerobic color removal efficiency and azo reductase activity of anaerobic microorganisms were adversely affected by the addition of oxygen. Color removal efficiencies of the anaerobic phases decreased from 80% down to 42 and 38% for the limited oxygen conditions of 20 mL/min and 40 mL/min, respectively. It was observed that the activity of catechol 2,3‐dioxygenase and catechol 1,2‐dioxygenase, involved in breakage of aromatic rings, increased after they are exposed to oxygen limited conditions compared to fully anaerobic conditions. It was also observed that catechol 1,2‐dioxygenase enzyme activity increased by increasing the oxygen level on oxygen limited conditions in the anaerobic zone.     

Changes in reproduction for subtropical cutlassfish Trichiurus japonicus reflect variation in temperature and population demography

Many subtropical fishes spawn multiple batches throughout a year. To understand plasticity in their reproductive output, we evaluated variation in oocyte size and batch fecundity for an exploited subtropical cutlassfish, Trichiurus japonicus, between two temperature periods (warm vs. cold) on the NE and SW coasts of Taiwan, northwestern Pacific. Given greater temperature variability on NE compared with SW coast, we hypothesized greater changes between warm and cold periods in oocyte size and fecundity for T. japonicus on the NE coast. We found opposite changes in sizes of ripe oocytes between periods (cold > warm on the NE but warm > cold on the SW coast) but consistent patterns in batch fecundity between coasts (warm > cold). Furthermore, the between-period patterns in female length were consistent on both coasts (warm > cold). The differential between-period patterns in oocyte size were related to potential adaptive responses to differential thermal environments between coasts, whereas the changes in fecundity mainly involved plastic processes (e.g., changes in population demography or movement). Together, our findings suggest that variability of temperature and maternal effects underlie recruitment variability of T. japonicus.     

矿山尾砂表生地球化学过程实验研究

在对石菉铜锡矿和河台金矿层砂矿物物相及化学组成研究基础上，利用自行设计的大口径淋滤柱开展了淋滤实验和静置浸泡(溶解)实验。研究结果表明，矿山层矿排放水不一定是酸性，它取决于矿床脉石矿物、赋矿的岩石及其次生蚀变矿物的酸缓冲能力。矿山排放水的组成是地表或地下水与矿山层砂中矿物和氢氧化物及非品态物质相互作用的结果，元素的赋存状态对其被淋滤的程度有很大影响。优先流能使重金属大量带出，因此要尽量防止优先流的形成。研究结果可为矿山综合整治和修复提供重要依据。     

基于GAMIT的基线解算应用探究

GAMIT基线解算是GPS数据分析和处理的重要方法。本文主要介绍利用虚拟的linux系统,以GAMIT软件进行精确定位、基线解算的批处理过程。对GAMIT软件安装过程进行详细的介绍,并利用基站的数据信息进行基线解算,对结算结果进行分析并得出结论,其目的在于解算后能形成模块以进行不同点的精确定位。