南水北调中线工程对汉江中下游工业发展的影响

南水北调中线工程计划从丹江口水库向我国北方每年调水１４５亿ｍ＾３,汉江丹江口以下地区的水资源量将随之相应减少。汉江中下游地区是湖北省盐化工、机械、石油、食品、化肥、电力的重要生产地区,是湖北省的汽车工业走廊,其经济在湖北省占有举足轻重的地位。由于经济的迅速发展,下世纪工农业生产和人民生活对水资源的需求将从现在的１４０亿ｍ＾３增加到２５０亿ｍ＾３以上,需水量将达到水资源量的５８％,潜伏着严重的水资源     

基于遥感与GIS的土地利用动态变化研究

土地是人类社会经济活动的载体；土地利用是指人类对作为生产生活资料的土地的利用方式和强度；而土地利用动态变化则反映了土地利用方式的发展变化趋势。土地利用动态变化在数量，方式，强度，结构和趋势等方面存在很大的差异。全面，客观地反映土地利用动态变化有利于正确认识当前土地利用中合理和不合理的利用方式，为制定长期，可持续发展的土地管理和土地规划提供依据。遥感技术提供巨大而丰富的信息源，GIS技术具有强大的数据处理，空间分析等功能，二者的结合有着传统方式无法比拟的优越性，具有周期短，效率高，费用低等特点，在土地利用变化监测中发挥着巨大的作用。制定详细的技术手段，对重庆市15年间的土地利用及其动态变化在时间序列和空间序列上加以分析，阐明这种变化的外在表象，即耕地，林地的减少和城镇用地的增加；同时分析这种变化的内在驱动力主要为自然环境（坡度，高程，土壤等）和人文要素（经济条件与人口压力等）。为国土资源的有效可持续利用提供决策依据。     

Increase in biodegradation of dimethyl phthalate by Closterium lunula using inorganic carbon

The effect and mechanism of inorganic carbon (IC) on the biodegradation of dimethyl phthalate (DMP) by a green microalga Closterium lunula was investigated. The growth of this microalga and the biodegradation of DMP were significantly enhanced when the initial IC was increased. An intermediate product of DMP biodegradation was identified as phthalic acid (PA) that was accumulated and caused a sharp decrease in pH of microalgal culture medium, which inhibited both the growth of microalga and the biodegradation of DMP. A suggested second-order kinetic equation of organic pollutant biodegradation by microalgae (-dC/dt = kNr) fitted well with the experimental data. The increase of IC caused a decline in biodegradation rate constant for organic carbon (k) and an increase in growth (N) by supplying a favorite carbon source and mitigating the decrease of pH. As the net effect, the overall biodegradation rate of DMP was promoted as IC increased, which was dominated by the increase of microalgal growth.     

Acute toxicity and genotoxicity of two novel pesticides on amphibian, Rana N. Hallowell

Imidacloprid [1-(6-chloro-3-pyridylmethyl)-N-nitro-imidazolidin-2-ylideneamine] and RH-5849 [2'-benzoyl-l'-tert-butylbenzoylhydrazinel] are two pesticides used in China since 1992. In the present study we conducted acute toxicity test, micronucleus (MN) test and comet assay of the two pesticides on amphibian, Rana N. Hallowell, a sensitive organism suitable for acting as the bio-indicator of aquatic and agricultural ecosystems. The values of LC50-48 h of imidacloprid were found to be 165 mg l(-1) for tadpoles of Rana limnocharis and 219 mg l(-1) for tadpoles of Rana N. Hallowell. On the other hand, RH-5849 showed no acute toxicity to tadpoles during the 96 h exposure even it was saturated in the test solutions. There were significant differences in the MN frequencies between the negative controls and the treated groups at the dose of 8 mg l(-1) for imidacloprid (p < 0.05) and 40 mg l(-1) for RH-5849 (p < 0.01). Comet assay found significant differences (p < 0.01) in the distributions of DNA damage grades between the negative controls and groups treated in vitro with 0.05, 0.1, 0.2 and 0.5 mg l(-1) of imidacloprid and 5, 25, 50 and 100 mg l(-1) of RH-5849, respectively. DNA damage scores increased with the exposure levels of the two pesticides and dose-effect relationships were observed for both imidacloprid (r2 = 0.92) and RH-5849 (r2 = 0.98). The MN test and comet assay revealed potential adverse effects of the two pesticides on DNA in the erythrocytes of amphibians in aquatic and agricultural ecosystems.     

Retention equations of nonionic organic chemicals in soil column chromatography with methanol-water eluents

Research efforts dealing with chemical transportation in soils are needed to prevent damage to ground water. Methanol-containing solvents can increase the translocation of nonionic organic chemicals (NOCs). In this study, a general log-linear retention equation, log k' = log k'w - Sphi (Eq. [1]), was developed to describe the mobilities of NOCs in soil column chromatography (SCC). The term phi denotes the volume fraction of methanol in eluent, k' is the capacity factor of a solute at a certain phi value, and log k'w and -S are the intercept and slope of the log k' vs. phi plot. Two reference soils (GSE 17204 and GSE 17205) were used as packing materials, and were eluted by isocratic methanol-water mixtures. A model of linear solvation energy relationships (LSER) was applied to analyze the k' from molecular interactions. The most important factor determining the transportation was found to be the solute hydrophobic partition in soils, and the second-most important factor was the solute hydrogen-bond basicity (hydrogen-bond accepting ability), while the less important factor was the solute dipolarity-polarizability. The solute hydrogen-bond acidity (hydrogen-bond donating ability) was statistically unimportant and deletable. From the LSER model, one could also obtain Eq. [1]. The experimental k' data of 121 NOCs can be accurately explained by Eq. [1]. The equation is promising to estimate the solute mobility in pure water by extrapolating from lower-capacity factors obtained in methanol-water mixed eluents.     

Molecular mechanisms of nickel carcinogenesis: gene silencing by nickel delivery to the nucleus and gene activation/inactivation by nickel-induced cell signaling

We have summarized the molecular and cellular events involved in nickel (Ni) compound induced carcinogenesis. The major hypothesis for nickel carcinogenic action has involved the ability of the Ni compound to deliver high concentrations of Ni intracellularly, enter the nucleus and interact with chromatin. Ni has been found to selectively damage heterochromatin, and a major action of Ni is its ability to silence the expression of genes located near heterochromatin by inducing a loss of histone H4 and H3 acetylation and DNA hypermethylation. When Ni silences critical genes, such as tumor suppressor genes, the cell is altered to a greater state of neoplastic transformation. The carcinogenic hazard of Ni compounds has been directly related to the ability of that Ni compound to raise the intracellular Ni ions. The mechanisms of Ni-induced gene silencing will be discussed. However, recently it has been found that soluble Ni ions can interact with the cell surface receptors and activate cell signaling resulting in the induction of a variety of cellular genes. In particular, the Ca and hypoxia inducible factor pathway is activated in all cells exposed to soluble Ni ions. In the case of HIF-1 induction, a cell is now equipped with the expression of a variety of genes that will allow the cell to survive the lack of oxygen and thus should enable a previously initiated cancer cell to progress into a full malignant state and metastasize. These new findings support the view that soluble Ni ions exhibit carcinogenic potential by activating cell promotion and lend strength to the epidemiological data showing soluble Ni to be associated with cancer risk in Ni refinery workers.     

Carbon disulfide at a Chinese viscose factory external and internal exposure assessment

This article presents the results of carbon disulfide exposure measurements in a Chinese viscose rayon factory. The objectives of the study were to identify the external exposure levels at a large factory and to investigate the 2-thiothiazolidine-4-carboxylic acid (TTCA) concentrations in the urine of the subjects who were exposed to carbon disulfide in the working place atmosphere. The metabolism of carbon disulfide in the exposed subjects was also studied in order to demonstrate the best points in time for the internal exposure sampling. The measurement of the amount of personal exposure to carbon disulfide in the air of the workplace was performed by GC-FPD; the presence of TTCA in the workers urine was analyzed by use of a modified HPLC method. The kinetics of TTCA excretion was studied by analyses at different time-points both during and after exposure to carbon disulfide in the subjects. A total of 155 personal samples were obtained. The carbon disulfide concentration in the staple viscose hall was 13.72 +/- 1.12 mg m-3 in terms of the geometric mean +/- geometric standard deviation, and was 20.05 +/- 1.33 mg m-3 in the filament spinning hall. The TTCA values in the subjects who worked in the staple spinning hall were 1.18 +/- 0.43 mg g-1 creatinine and 1.07 +/- 0.38 mg g-1 creatinine for subjects working in the filament spinning hall. The best time for TTCA sampling is at the end of the working shift, the TTCA excretion was stable for a period of 4-12 h after exposure of the subjects to the carbon disulfide. It might be that the Chinese have different anthropometric characteristics; a sampling bias may therefore appear among different races.     

氯离子选择性电极法测定钻井废水氯离子含量

利用氯离子选择性电极测定钻井废水中的氯离子含量，分别用两种方法对钻井废水进行了预处理，氯离子在0-250mg/L的范围内线形关系良好，相关系数为0.9968,并且重现性和选择性良好、精密度与准确度较理想。     

山东省水环境自动监测监控系统数据的应用设计和使用方法

山东省水环境自动监测监控子系统的主要功能是将全省水质自动站数据利用计算机网络、数据仓库等技术导入到环境监测数据仓库中，实现全省水环境自动监测的统一监控和监测信息的自动管理和发布。本文简单介绍了系统担制中心端监测数据统计应用部分的功能设计和实现方法。     

二次催化-固定床生物氧化降解焦化废水的试验研究

制备了一种铁碳基／过渡金属复合催化剂，其物质摩尔配比为Fe：C：TiO2：MnO2：ZnO=2：1：1：1：0．3，使用该催化剂拟定了二次催化—固定床生物氧化降解流程。在pH＝6、温度=90℃的条件下，用该流程处理煤化工工业所产生的洗煤气净化脱酚、蒸氨剩余废水，在无需对原废水进行稀释的前提下可很好地对此废水进行处理，使处理后的出水指标达到《污水综合排放标准》（GB89r78—1966）中规定的二级排放标准。