La在模拟水生态系统中的动力学行为

采用140La放射示踪技术,研究了稀土元素镧（La）在模拟水生态系统各组分中的迁移分布规律．并建立了相应的数学模型．结果表明,La在模拟水生态系统各组分中的积累率大小依次为：金鱼藻＞底泥＞螺蛳＞鱼,La在系统内的动态变化规律可用封闭分室模型来描述．     

建筑物基底反力的实时监测与分析

以某大楼的基底反力监测为例 ,阐述了建筑物基底反力实时监测的原理与方法。监测分析结果表明 ,对在建建筑物进行的基底反力实时监测直接反映了土体受力状态 ,可间接得出桩基的受力情况。     

中华鳖出血性肠炎的药物防治研究

对由实验定筛选的中华鳖出血肠炎病病原菌的最佳防治药物为本正交试验的第6组,即A2B3C1,其抑菌圈达21.5mm.临床应用中采用中西结合复方制剂,即用第6组试验药物再加上中药白头翁汤(加减),其疗效更佳.     

地震学综合定量预报方法在华东地区地震预测中的应用研究

本文应用地震学综合定量预报方法,结合区域地震活动特点,在华东地区进行了分区实际预报效能检验.结果表明该方法在华东地区有5个区域通过R值检验,效果较好,有4个区域未能通过R值检验;并对通过检验的区域地震活动趋势进行了分析.     

水样发光细菌急性毒性测试的方式与表征

选取不同类型的环境和污染源水样开展了发光细菌毒性测试,针对不同环境管理目标,探讨了急性毒性定量表征方式。发光细菌急性毒性测试在环境应急监测、水源早期生物预警中,采用绘制毒性预警基线图的方式比较可行。在污染源监督监测中,对于发光抑制率低于60%、无法求出EC50的样品,采用等效毒性参照物的质量浓度表征废水的毒性;对于发光抑制率高于60%,采用稀释因子表示样品的毒性更直观可靠。     

用蚕豆根尖细胞微核技术检测乌鲁木齐河水质

应用蚕豆根尖细胞微核技术对乌鲁木齐水质进行检测,测定各样点水样诱导的蚕豆根尖微核千分率及综合污染指数,并进行Ｆ检验,结果表明,各样点ＭＣＮ‰有显著性差异,２０个样点中有１１个样点 的综合污染指数大于２,４个样点水样的综合污染指数大于３．５,和对照组相比有显著差异。所获得数据表明乌鲁木齐河水质受到较为了严重的致突变性污染。     

外力作用下管道内表面缺陷处裂纹扩展研究

为提高油气管道安全风险评估的准确性,以含内表面缺陷管道为研究对象,利用ABAQUS软件线弹性及弹塑性分析不同尺寸缺陷对裂纹萌生特征的影响;采用扩展有限元法,建立管道3点弯曲模型与全尺寸静载物理试验,并非线性拟合裂纹扩展尺寸,研究内表面缺陷处裂纹扩展情况.研究结果表明:内表面缺陷中心处极易萌生裂纹,随着缺陷尺寸的增大,裂...     

Mathematical Modeling of Column and Field Dense Nonaqueous Phase Liquid Tracer Tests

Mathematical models for the simulation of dense nonaqueous phase liquid tracer tests (DTTs) in laboratory columns and in the field are developed and examined. The DTT technique is a means of estimating the quantity of dense nonaqueous phase liquid (DNAPL) in a domain of interest in an aquifer. The two-dimensional field DTT model uses the Method of Principal Directions and an asymmetrical upwind algorithm for describing advective transport. Both models include diffusion transport of tracer into and from low-permeability porous structures such as clay lenses, as well as the mass transport kinetics of partitioning tracer to and from the DNAPL droplets. The dependence of the effluent tracer concentration curves on the parameters of the models is explored, and conclusions are drawn regarding the applicability of, and several possible problems with, the DTT technique. Model results indicate that the DTT performs well at locating distributed droplets of DNAPL, but is unlikely to be useful in the assessment of pooled DNAPL.     

用Ames试验检测水源水和自来水中的遗传毒性

用微伤寒沙门氏菌／哺乳动物微粒体酶系的Ａｍａｅｓ试验,研究了不同季节物水源水及管网自来水中的遗传毒性,以ＸＡＤ２树脂为吸附剂,以丙酮－甲醇的混合液为洗脱液,浓率水样中的有机物,并对部分阳性水样进行有机成分的定性分析。结果发现：１３个水样中有７个样品在淡需要代谢活化系统Ｓ９的情况下,可诱导鼠伤寒沙门氏菌碱基移码型菌株的回复突变;不同水样在不同季节不同的诱导作用;同时通过ＧＣ／ＭＳ方法分析,发现阳性水     

Diffusion mechanism of lindane into wood charcoal

Abstract

The wood charcoal treated by 1N HNO₃ (WCT) was used to remove toxic chlorinated pesticide lindane (y‐HCH) residue from water by the sorption process. Using a simple first order reversible kinetics constants and half time equations, the film and pore diffusion coefficients were determined. Film diffusion was found to be rate limiting step in sorbing lindane by WCT. This was further authenticated by kinetics studies at different initial sorbate concentrations, different sorbent sizes, and different agitation speeds besides interruption test. A pore diffusion model was used to fit the data of kinetics in continuously mixed batch reactors (CMBR), and the tortuosity, external resistance, and surface diffusion effects on lindane sorption by WCT were noticed. The tortuosity values of 15 to 28 were obtained for WCT‐lindane system.