滇池流域水资源的开发与保护

本文介绍了滇池流域的自然条件和社会经济发展,分析了水资源特点,对其开发现状和供需预测作了评述,并提出了进一步开发和保护水资源的建议。     

Biosorption effects of copper ions on Candida utilis under negative pressure cavitation

Under the optimal condition of copper ions adsorption on yeast,we found some different effects among static adsorption, shaking adsorption and negative pressure cavitation adsorption, and the methods of yeast with different pretreatments also affect adsorption of copper ions. At the same time, the change of intercellular pH before and after adsorption of copper with BCECF was studied. The copper distribution was located by using PhenGreen （dipotassium salt and diacetate）, and the surface of yeast was observed by an atomic force microscope. The results showed that negative pressure cavitation can improve bioadsorption capacity of copper ions on yeast. However, the yeasts＇ pretreatment has a higher effect on bioadsorption. It indicates that heavy metal bioadsorption on yeast has much relation with its cellular molecule basis. With the adsorping, the intercellular pH of yeast increased gradually and changed from acidity to alkalescence. These results may suggest that negative pressure cavitation can compel heavy metals to transfer from the cell surface into inside cell and make the surface of yeast coarse.     

Evaluation of accelerated dechlorination of p,p'-DDT in acidic paddy soil

The reductive dechlorination and behavior of p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT) was investigated in a paddy soil. Treatment with 5% (w/w) metallic iron (Fe(0)) resulted in sharp decrease of p,p'-DDT, whereas there was no extra effect when 2% (w/w) aluminum sulfate (Al(2)(SO(4))(3)) was added to the Fe(0) treatment. These results suggest that Fe(0) could effectively promote the reductive dechlorination of p,p'-DDT and its metabolites while Al(2)(SO(4))(3) did not show any effect on those processes. Furthermore, p,p'-DDT and its daughter compounds inhibited holistic soil respiration greatly at first but could be metabolized by certain species of indigenous microorganisms after a period of adaptation time in the soil. When treated with Fe(0), the polluted soil produced much less CO(2) while the addition of Al(2)(SO(4))(3) counteracted its negative effect to much extent.     

Use of stationary and mobile measurements to study power plant emissions

This paper presents a technique to study air pollution by combining high spatial resolution data obtained by a mobile platform and those measured by conventional stationary stations. Conventional stations provide time-series point data but cannot yield information that is distant from the sites. This can be complemented or supplemented by mobile measurements in the vicinity of the conventional sites. Together, the combined dataset yields a clearer and more precise picture of the dispersion and the transformation of pollutants in the atmosphere in a fixed time frame. Several experiments were conducted in the years 2002-2003 to track the impact of power plant plumes on ground receptors in the immediate vicinity (within a radius of 30 km) of the plants, using a combined mobile and stationary dataset. The mobile data allowed the identification of emissions from coal-fired and gas-fired power plants. Coal-fired power plants were the major source of sulfur dioxide (SO2), whereas nitrogen oxides (NOx) emitted from the gas-fired power plant played an important role in the formation of ozone (O3) at ground level. The mobile data showed that two particle size distribution regimes were detected: one had a dominant accumulation mode at 0.40-0.65 microm and the other at 0.65-1 microm. The existence of particles characterized by their mode at 0.65-1 microm and formed by in-cloud processes suggests that vehicular emissions were not the important source. Other local sources, such as power plants (elevated emission), were the likely sources, because Hong Kong does not have much manufacturing industry.     

国家资源安全及其系统分析

资源安全是一个国家或地区可以持续、稳定、及时、足量和经济地获取所需自然资源的状态或能力。影响资源安全的因素主要包括结构、质量、数量、空间、价格、技术、制度等。分析了国家资源安全的主体目标导向性、实现过程可调控性、发展演化的长期性、空间层次差异性和系统内外互动性等特性。构建了包括社会、经济、资源、生态环境、政策法律等子系统在内的国家资源安全的系统分析框架。运用PSR模型，进行了国家资源安全系统动力学分析。     

实验室间呼吸性粉尘中石英含量测定方法的研究

实验室间呼吸性粉尘中石英含量测定方法的研究目的在于研究影响实验室间测定数据差异性的因素 ,探讨改善测试技术提高精度方法 ;其方法是制备 3种试验样品 ,进行实验室间共同测试 ;其测试结果 :7个实验室对 3种样品报告了 6 2个数据 ,2个实验室采用 XRD法、5个采用 IR法 ,3种样品的测试变异性分别为 30 .5 %、16 .1%、6 9% ;其中 XRD为 (2 5 .2～ 6 7) %、IR为 (13.9～5 7) %。本研究课题的最终结论 :实验室间测定数据具有可比性 ,达到国际 80年代水平 ;标准物质应统一 ,制样、测试等技术有待提高。     

Fate of PM2.5-bound PAHs in Xiangyang, central China during 2018 Chinese spring festival: Influence of fireworks burning and air-mass transport

Variations of levels, possible source and air mass transmission were investigated for 16 USEPA priority-controlled PAHs in PM_2.5 during 2018 Chinese Spring Festival (CSF) in Xiangyang City, central China which is the North-South pollutant airmass transport channel of China. Totally 37 samples were collected. Mass concentrations of Σ₁₆PAHs for the Pre–CSF day (Pre–CSFD), during the CSF day (CSFD) and after the CSF day (Af–CSFD) are 33.78 ± 17.68 ng/m³, 22.98 ± 6.49 ng/m³, and 8.99 ± 4.44 ng/m³, respectively. High resolution samples showed that Σ₁₆PAHs are higher in the morning (06:00–11:00) or afternoon (11:30–16:30), than those in the evening (17:00–22:00) and at night (22:30–05:30), whereas the result is reversed during the CSFD. Fireworks burning can obviously increase the mass concentration of PAHs. Air mass trajectory indicated that Xiangyang is a sink area of pollutants for northwest and southeast, and the sources of the northeast and southwest. The air mass only can be transmitted out through northeast and southwest. It is effective for improvement of air quality in Wuhan and Hunan to control fireworks emission in Henan and local areas. Fireworks burning was an important source for PAHs during CSFD, biomass, coal combustion, and traffic emission were the main sources of PAHs for Pre–CSFD and Af–CSFD periods. The health risk on the CSFD was higher than the acceptable levels, especially during the intensive fireworks burning, the risk value far exceed 1.0 × 10^?4, controlling burning fireworks is required.     

基于流态化作用的吸附反应动力学和穿透特征

基于流态化作用的吸附反应动力学和穿透特征研究还鲜见报道.以苯酚为吸附质、活性炭为吸附剂,探讨了不同流态化紊流强度对基于流态化作用的吸附效率、吸附动力学特性、吸附反应穿透曲线和饱和吸附量的影响,并与相同条件的固定床吸附反应器进行了对比研究.结果表明,表观流速为8 mm·s-1和13 mm·s-1时,基于流态化和固定态的活性炭在5 min内的吸附效率均达到93%以上,吸附反应均符合经典二级动力学方程,且其相关系数大于0.999.穿透实验结果表明,表观流速为6 mm·s-1和8 mm·s-1时,基于流态化的活性炭对苯酚的吸附总量分别较固定态高8.77 mg·g-1和24.70 mg·g-1.可见,基于流态化吸附反应器与基于固定态吸附反应器相比,具有吸附反应效率高,吸附总量大的特征.     

微污染水源水处理技术探析

近年来,我国不少地区饮用水水源水质日益恶化,水质净化面临新的问题。通过对微污染水源水处理技术的分析,阐明了微污染水处理的基本理论,探讨了强化传统处理工艺、预处理技术、深化处理技术的作用效果与机理,展望了我国饮用水源水处理发展趋势。