苯酚对两种微囊藻生长的作用效应

用不同浓度的苯酚处理无毒铜绿微囊藻和有毒铜绿微囊藻。结果显示不加苯酚处理时，有毒藻生长量明显高于无毒藻；100μg／mL的苯酚促进无毒藻生长而抑制有毒藻的生长；苯酚浓度增至200μg／mL，无毒藻的生长才受到抑制。高浓度苯酚胁迫下的藻细胞：光合速率大幅度降低；可溶性蛋白含量减少；细胞膜透性增大；超氧阴离子(O2^-)产生速率和丙二醛(MDA)相对含量升高；超氧化物歧化酶(SOD)活性降低。这些变化有毒藻较无毒藻更显著。表明：有毒微囊藻是水华中的优势种群；两种藻中有毒藻对苯酚的敏感性更大。     

安徽省长江以北地区土壤水溶性氟含量及分布特征

采集安徽省长江以北地区有代表性土壤样品３４７个，测定了其水溶性氟含量。结果表明，土壤水溶性氟含量范围０３８～１２６９ｍｇ／ｋｇ，平均为２３８ｍｇ／ｋｇ。地区分布是南低北高，以淮北宿州和阜阳地区为最高，平均含量在３ｍｇ／ｋｇ以上。主要土壤类型土壤水溶性氟含量顺序是砂姜黑土、潮土＞黄棕壤、紫色土＞水稻土＞石灰土、粗骨土。不同母质土壤水溶性氟含量顺序是古黄土性河湖相沉积物＞黄泛冲积物＞紫色砂岩＞下蜀黄土＞石灰岩＞酸性结晶岩风化物＞河流冲积物。土壤水溶性氟含量与土壤ｐＨ呈正相关。ｐＨ高的黄泛冲积物和古黄土性河湖相沉积物母质土壤含水溶性氟多，该土壤地区发生氟中毒可能性较大。     

Ultraviolet-H2O2 oxidation of surfactants

This paper describes a study of the treatment of surfactant synthetic solutions by chemical and photolytic oxidation. Synthetic solutions of linear alkylbenzene sulfonates (LAS) are treated in this work as this is a model compound commonly used in the formulation of detergents, with a great presence in urban and industrial waste-waters. The application of ultraviolet (UV) radiation combined with hydrogen peroxide to oxidize linear alkylbenzene sulfonates (LAS) is shown to be suitable as a primary oxidation step since conversions of about 50% of the original compounds are achieved in the most favorable cases. Initially, the influence of the operating variables on the degradation levels is analyzed in this work. A kinetic model that considers the contributions of both direct photolysis and radical attack is also worked out. Direct photolysis is performed to determine the quantum yield in the single photodecomposition reaction. In addition, the rate constant of the reaction between hydroxyl radicals and linear alkylbenzene sulfonates in the oxidizing system H₂O₂/UV is determined for different operational conditions. Finally, the contribution of each oxidation pathway is quantified, resulting in a higher contribution of the radical reaction than of photolysis in all cases.     

Interaction between water soluble and volatile compounds of Cistus ladanifer L.

Summary. Phytotoxic activity of single and combined application of water soluble and volatile compounds of Cistus ladanifer on germination and early root growth of subterranean clover was investigated. Total germination, lag and speed of germination were both inhibited and stimulated, with the activity of volatiles on total germination depending upon the presence of water solubles. Antagonism between water solubles and volatiles was always found, resulting in a reduction of inhibition or a shift from inhibition to stimulation. It is suggested that the simultaneous presence of water solubles and volatiles might result in changes of the chemical nature of metabolites released by C. ladanifer. Early root growth was always inhibited but only by water solubles, and no interaction was found. The ecological implications of these results are discussed in terms of the exhaustion of competitors seedbanks by a two-step process in which germination is less inhibited or even stimulated by water solubles and volatiles, followed by a stronger and volatiles-independent inhibition of early root growth. Received 13 June 2001; accepted 13 Dezember 2001.     

汽车尾气净化非贵金属催化剂SO2中毒机理研究

用TPD,IR,XPS等方法研究了汽车尾气净化的复合氧化物催化剂SO_2中毒机理。结果表明,催化剂SO_2中毒失(?),首先是SO_2在催化剂活性中心上进行化学吸附,然后部分SO_2与活性组分生成相应的亚硫酸盐和硫盐酸,从而使催化剂失活。SO_2的化学吸附及部分生成相应的亚硫酸盐,与生成硫酸盐相比,对催化剂失活的影响,前者更为明显。     

苯磺酰基环烷烃甲酸酯结构对发光菌的毒性影响

测定了一批具有大小不同碳环的的苯磺酰基环烷烃甲酸酯对发光菌的毒性数据，值得注意的是碳环大小的改变会影响化合物的毒性，碳环对毒性的影响按三元环〉四元环〉五元环〉六元环的顺序减小。     

双波长标准加入法同时测定水中硝酸盐和亚硝酸盐

本文应用双波长标准加入法同时测定了硝酸盐和亚硝酸盐，在研究硝酸盐和亚硝酸盐紫外光谱的基础上，精确选择亚硝酸盐等吸收点波长２０２．５ｎｍ，２１６．５ｎｍ为测定波长。亚硝酸盐含量回归方程经推导得Ｃ＝－３．８４１＋１５６．６Ａ，相关系Ｒ＝１．０００。将该法用于合成样品及实际水样分析，所得结果较满意。     

城市生态系统的预测与综合评价的思想体系

本方针对国内外城市生态系统的研究,提出了一套预测一评价一对策的思想体系,并对其预测、评价方法作了初步理论探讨.     

不同有机物料在潮棕壤中有机碳分解进程

用尼龙网袋法研究了特定年度中，不同月份间有机物料在潮棕壤旱田、水田中有机碳分解速率及C／N变化。结果表明，4种物料(玉米秸和玉米根，水稻秸和水稻根)在潮棕壤地区温度、湿度适宜的前3个月(1999年7—月)迅速分解，之后进入缓慢分解阶段，其中根的分解残留率始终高于秸秆。经计算约有2／3的玉米根和稻根腐解产物残留在土壤里；分解至试验结束。所有物料的C/N比都趋于一致，约在10—13之间，与土壤腐殖质的洲比非常相近，说明这些物料已基本完成其腐殖化过程，而成为较稳定的有机组分、这对增加土壤有机质、培肥土壤非常重要。     

纳滤膜处理高浓度废液分离规律研究

利用管式或卷式纳滤膜处理废弃母液，在固定工艺条件下，透过液通量与浓缩时间呈一定数学关系；当浓缩进行到最后，透过液中的COD浓度会突然提高，该突然下降时间应长连续浓缩时间，抗生素截留率的变化规律基本与COD的去除率相同，但数值不同。利用COD的变化规律基本可以确定抗生素的变化趋势。