基于N，N─二甲基苯胺与NO_2~－─对氨基苯磺酸重氮盐的偶联反应示波极谱法测定NO_2~－

报道了利用Ｎ，Ｎ─二甲基苯胺为偶联试剂的Ｃｒｉｅｓｓ反应以示波极谱法测定ＮＯ_２~－的测试方法。在拟定的实验条件下，ＮＯ_２~－在４．０×１０~－３～４．８×１０~－１μｇ／ｍｌ范围内与极谱波波高呈良好的线性关系。环境水测定的相对标准偏差小于ｌ％，回收率在９７％～１０１％之间。     

热带海洋环境中BHC和DDT的行为特征研究Ⅰ.中国珠江口区旱季BHC和DDT的含量与分布

本文于1994年11月用气相色谱法研究了旱季珠江口区环境中BHC和DDT的含量与分布。结果表明，表层海水BHC含量为0.187μg/L，DDT为0.080μｇ/L；底层海水BHC为0.117μｇ／L，DDT为0.506μｇ／L。沉积物BHC为11.15×10－9（干），DDT为33.46×10－9（干）。海水中的盐度、DO、C     

炼油厂污水处理负荷的削减措施

总结和分析了某厂削减污水处理负荷的主要措施及效益，预测该厂在达到16000kt/a以上加工规模时的污水处理负荷。     

自然灾害变动的集成预测模型及其应用

本文提出了以非线性回归拟合发展趋势、正弦函数逼近周期变动和马尔可夫链刻划随机扰动的集成预测模型，并应用于山东省农业自然灾害成灾面积的变动规律模拟，得到了较好的预测效果。理论和实践表明，集成预测模型优于传统的单模型预测，为预测具有复杂机制的自然灾害演变提供了一种新方法。     

Monitoring and identification of spatiotemporal landscape changes in multiple remote sensing images by using a stratified conditional Latin hypercube sampling approach and geostatistical simulation

This study develops a stratified conditional Latin hypercube sampling (scLHS) approach for multiple, remotely sensed, normalized difference vegetation index (NDVI) images. The objective is to sample, monitor, and delineate spatiotemporal landscape changes, including spatial heterogeneity and variability, in a given area. The scLHS approach, which is based on the variance quadtree technique (VQT) and the conditional Latin hypercube sampling (cLHS) method, selects samples in order to delineate landscape changes from multiple NDVI images. The images are then mapped for calibration and validation by using sequential Gaussian simulation (SGS) with the scLHS selected samples. Spatial statistical results indicate that in terms of their statistical distribution, spatial distribution, and spatial variation, the statistics and variograms of the scLHS samples resemble those of multiple NDVI images more closely than those of cLHS and VQT samples. Moreover, the accuracy of simulated NDVI images based on SGS with scLHS samples is significantly better than that of simulated NDVI images based on SGS with cLHS samples and VQT samples, respectively. However, the proposed approach efficiently monitors the spatial characteristics of landscape changes, including the statistics, spatial variability, and heterogeneity of NDVI images. In addition, SGS with the scLHS samples effectively reproduces spatial patterns and landscape changes in multiple NDVI images.     

福建省热带气旋暴雨型地质灾害特征分析

福建是受热带气旋影响较严重的省份,又是一个多山的省份,每年都有因热带气旋暴雨诱发滑坡等地质灾害造成巨大人员伤亡和经济损失的事例发生.通过分析福建省1990～2006年热带气旋暴雨诱发的地质灾害个例,发现热带气旋暴雨型地质灾害的规模和强度均比雨季暴雨诱发的地质灾害大;它的发生与热带气旋路径、过程雨量和当日雨量关系密切,地质灾害主要发生在强降水后的48 h内;热带气旋登陆前后,若有偏东急流、西南季风、冷空气、暖式切变等系统共同作用,对暴雨具有增幅作用,极易引发地质灾害.     

Modeling porosity reductions caused by mineral fouling in continuous-wall permeable reactive barriers

A study was conducted to assess key factors to include when modeling porosity reductions caused by mineral fouling in permeable reactive barriers (PRBs) containing granular zero valent iron. The public domain codes MODFLOW and RT3D were used and a geochemical algorithm was developed for RT3D to simulate geochemical reactions occurring in PRBs. Results of simulations conducted with the model show that the largest porosity reductions occur between the entrance and mid-plane of the PRB as a result of precipitation of carbonate minerals and that smaller porosity reductions occur between the mid-plane and exit face due to precipitation of ferrous hydroxide. These findings are consistent with field and laboratory observations, as well as modeling predictions made by others. Parametric studies were conducted to identify the most important variables to include in a model evaluating porosity reduction. These studies showed that three minerals (CaCO3, FeCO3, and Fe(OH)2 (am)) account for more than 99% of the porosity reductions that were predicted. The porosity reduction is sensitive to influent concentrations of HCO3-, Ca2+, CO3(2-), and dissolved oxygen, the anaerobic iron corrosion rate, and the rates of CaCO3 and FeCO3 formation. The predictions also show that porosity reductions in PRBs can be spatially variable and mineral forming ions penetrate deeper into the PRB as a result of flow heterogeneities, which reflects the balance between the rate of mass transport and geochemical reaction rates. Level of aquifer heterogeneity and the contrast in hydraulic conductivity between the aquifer and PRB are the most important hydraulic variables affecting porosity reduction. Spatial continuity of aquifer hydraulic conductivity is less significant.     

公路地表灰尘及径流中颗粒物附着重金属对比研究

对北京城区北三环上北太平桥以西约300 m处路段地表灰尘及径流中不同粒径颗粒物附着重金属载荷进行对比研究.结果表明:(1)随着颗粒物粒径的增大,地表灰尘中颗粒物附着重金属浓度总体上逐渐降低;地表灰尘中<40.00 μm颗粒物附着重金属浓度最高;重金属载荷分布集中度不强,但主要集中在地表灰尘中<300.00 μm的颗粒物L.(2)地表径流中大部分重金属附着在<125.00 μm颗粒物上;0.45～10.00 μm颗粒物附着重金属载荷最高;0.45～40.00 μm颗粒物附着重金属载荷平均为77.1%.(3)地表灰尘中<40.00 μm的颗粒物的潜在水环境风险不太突出,但是其实际水环境影响却起主导作用.(4)进入水体的小粒径颗粒物质量分数升高是地表灰尘和径流重金届载荷随颗粒物粒径分布不同的重要原因之一;大气湿沉降对小粒径颗粒物重金属载荷可能会有一定的影响.     

苏州市工业用地地表径流污染特性研究

对苏州新区枫桥工业园湘江路段的10场有效降雨事件的地表径流污染特性进行了研究.研究表明.地表径流水质参数COD、SS、NH3-N、TN、TP均服从对数正态分布,在95%置信水平下,SS与COD、TP、TN之问存在线性相关性(R=0.45～0.72).统计了污染物事件平均浓度(EMC),COD、SS、NH3-N、TN、TP的EMC中值分别为213、491、2.65、5.19、1.07 mg/L,相对应的单位面积污染物负荷分别为1 898、4 375、24、46、10 kg/(hm2·a).与韩国Chongju工业区和上海市相比,SS负荷高是苏州新区枫桥工业园地表径流水质的主要特点,削减SS负荷对控制其非点源污染具有重要意义.