Assessing land use impacts on flood processes in complex terrain by using GIS and modeling approach

A distributed hydrologic modeling and GIS approach is applied for the assessment of land use impact in the Steinsel sub-basin, Alzette, Grand-Duchy of Luxembourg. The assessment focuses on the runoff contributions from different land use classes and the potential impact of land use changes on runoff generation. The results show that the direct runoff from urban areas is dominant for a flood event compared with runoff from other land use areas in this catchment, and tends to increase for small floods and for the dry season floods, whereas the interflow from forested, pasture and agricultural field areas contributes to the recession flow. Significant variations in flood volume, peak discharge, time to the peak, etc., are found from the model simulation based on the three hypothetical land use change scenarios.     

A study of the distribution of lead, cadmium and copper between water and kaolin, bentonite and a river sediment

Experiments were carried out to monitor the equilibrium distribution of lead, cadmium and copper between an aqueous phase modelling natural water and a solid phase modelling natural sediment, under varying conditions. The aqueous phase was analysed using ETAAS and differential pulse anodic stripping voltammetry (DPASV), whereas XRD and FTIR were used to study the solid phase. Sorption isotherms at constant pH were measured. Conditional distribution constants were calculated as functions of the pH, the time of equilibration and the amount of solid material. The results obtained stress the need for standardization of the approaches to the study of water-sediment interactions in order to be able to evaluate and compare the extensive data from field measurements and to predict these interactions.     

Pool of Dust Particles over the Asian Continent: Balloon-borne Optical Particle Counter and Ground-based Lidar Measurements at Dunhuang, China

Measurements of aerosols were made in 2001 and 2002 at Dunhuang (40 degrees 00'N, 94 degrees 30'E), China to understand the nature of atmospheric particles over the desert areas in the Asian continent. Balloon-borne measurements with an optical particle counter suggested that particle size and concentration had noticeable peaks in super micron size range not only in the boundary mixing layer but also in the free troposphere. Super-micron particle concentration largely decreased in the mid tropopause (from 5 to 10 km; above sea level, a.s.l.). Lidar measurements made during August 2002 at Dunhuang suggested the possibility that mixing of dust particles occurred from near the ground to about 6 km even under calm weather conditions, and a large depolarization ratio of particulate matter was found in the aerosol layer. The top of the aerosol layer was found at heights of nearly 6 km (a.s.l.). It is strongly suggested that nonspherical dust particles (Kosa particles) frequently diffused in the free atmosphere over the Taklamakan desert through small-scale turbulences and are possible sources of dust particles of weak Kosa events that have been identified in the free troposphere not only in spring but also in summer over Japanese archipelago. Electron microscopic experiments of the particles collected in the free troposphere confirmed that coarse and nonspherical particles observed by the mineral particle were major components of coarse mode (diameter larger than 1 microm) below about 5 km over Dunhuang, China.     

HNO_3─KI─MIBK萃取／原子吸收光谱法测定固体废物浸提液中的微量银

采用选择性较好的ＨＮＯ３—ＫＩ—ＭＩＢＫ萃取体系对铋渣和尾矿渣浸出液中的痕量银进行预分离富集后，用火焰原子吸收法（ＡＡＳ）进行测定。此法不仅变异系数小（约为３．１％），而且检出限比直接火焰ＡＡＳ法降低两个数量级，达０．５ｎｇ／ｍｌ．另外，还就作品细度对银测定结果的影响原因做了初步探讨。     

库仑滴定法测定一氧化碳

本文就一氧化碳的测定条件和CO氧化过程中氧化剂的选择进行了研究。试验表明:ReAO_4-Ⅱ为氧化CO的活性催化剂,转化率可达100％(在300℃以上),本法简便,可用于空气中一氧化碳的测定和催化剂对CO活性测试。     

液相化学发光分析在环境监测中的应用

介绍液相化学发光分析法的原理和特点以及十年来在我国环境监测中的应用。收录1983年～1991年国内的应用论文50余篇,作了较为系统全面的评述。     

扬子型铜矿床矿物稀土元素地球化学

本文较系统研究了扬子型铜矿床中有代表性的菱铁矿、胶黄铁矿、黄铁矿、磁黄铁矿、磁铁矿、黄铜矿及部分脉石矿物的稀土元素组成及特征，总结了展状矿石中和矽卡岩矿石中矿物稀土元素组成的特点及二者之间存在的明显差别，从一个方面探索扬子型铜矿床的成因。     

多介质环境目标值的应用

本文概述了多介质目标德的SAM/Ⅰ的方法。多介质目标值包括环境目标值和排放目标值。点源分析包括SAM/ⅠA,SAM/ⅠB,SAM/Ⅰ,SAM/Ⅱ。在缺少环境质量标准的情况下,使用多介质环境目标值有较强的适用性,且具有省时、省力、经济等特点。本文将多介质目标值的SAM/ⅠA点源分析方法引入聚氯乙烯生产废水的环境评价中,取得较为满意的结果。     

改进取样方法提高含油废水中CODcr值的准确度

化学需氧量(CODcr)和石油类都是中国实施水污染物排放总量控制指标,也是环境监测的常测项目.CODcr是反映水体中受还原性物质主要是有机物污染程度的综合性指标.矿物油和动、植物油统称为油类,是废水中常见的有机污染物,对CODcr的贡献较大.探索水体中CODcr值与油类物质含量之间的相关性,对CODcr值准确性的判断有一定指导意义.改进含油废水的取样方法,有利于提高CODcr测定值的准确性和代表性.     

地震安全性评价工作在城市建设中的重要作用

地震安全性评价工作在城市建设中起着非常重要的作用,为工程抗震提供精确的设计依据,提供科学合理的地震动参数,提出科学合理的设防要求,能够在一定程度上避免破坏性地震造成的损失,从而达到有效减灾的目的。