Fluoride and aluminium concentrations of tea plants and tea products from Sichuan Province,PR China

Some Tibetans in Sichuan Province in southwestern China have been suffering from fluorosis, due to drinking and eating tea with high fluoride (F) and aluminium (Al) contents. Tea plants, soils of tea plantations and tea products from Yaan, Gaoxian and Yibin Cities in Sichuan Province were investigated to evaluate the factors affecting F and Al contents in tea products. The F and Al concentrations of four commercial brands of brick teas were significantly higher than those of 11 brands of green teas. Chemical analysis indicated that total and available F and Al concentrations in tea plantation soils in Yaan and Gaoxian were within the normal range compared with acid soils in South China and tea soils in Fujian Province. Edaphic conditions did not contribute to the high F and Al concentrations in brick tea. Analysis of raw materials of brick tea indicated that old leaves were the major contributors to the high F and Al contents contained in brick tea. There were also great variations among different tea varieties in accumulating F and Al, and concentrations of F and Al in tea variety of Qianmei 303 were about 2-3-fold higher than the other three varieties. Selection of appropriate varieties would be important to lower F and Al contents in tea products.     

南京市区植物叶片氮、硫、铅含量与大气污染评价

通过对南京市区的各功能区植物叶片中的氮、硫、铅元素含量的分析，研究了植物大气环境污染指数，探讨了植物叶片的氮、硫、铅元素含量的季节变化，以及与城市大气环境污染之间的关系。结果表明，植物叶片中，硫、铅元素的含量随季节变化不断增加，而氮元素含量相应减少；各功能区的硫、铅元素含量明显高于清洁对照区；用植物污染指数可以综合评价大气环境的质量状况。     

微波解吸柠檬酸盐溶液中SO2实验研究

结合微波具有的热效应、非热效应特性,利用经改装的微波反应装置,研究了微波场下柠檬酸浓度、微波作用时间、微波功率、SO2初始浓度和搅拌速率对解吸柠檬酸盐溶液中SO2的影响,得出了影响SO2解吸率的基本规律和最佳解吸条件,并进行了分析.     

Growth and metal accumulation in vetiver and two Sesbania species on lead/zinc mine tailings

The lead (Pb)/zinc (Zn) tailings contained high concentrations of heavy metals (total Pb, Zn, Cu and Cd concentrations 4164, 4377, 35 and 32 mg kg(-1), respectively), and low contents of major nutrient elements (N, P, and K) and organic matter. A field trial was conducted to compare growth performance, metal accumulation of Vetiver (Vetiveria zizanioides) and two legume species (Sesbania rostrata and Sesbania sesban) grown on the tailings amended with domestic refuse and/or fertilizer. It was revealed that domestic refuse alone and the combination of domestic refuse and artificial fertilizer significantly improved the survival rates and growth of V. zizanioides and two Sesbania species, especially the combination. However, artificial fertilizer alone did not improve both the survival rate and growth performance of the plants grown on tailings. Roots of these species accumulated similar levels of heavy metals, but the shoots of two Sesbania species accumulated higher (3-4 folds) concentrations of Pb, Zn, Cu and Cd than shoots of V. zizanioides. Most of the heavy metals in V. zizanioides were accumulated in roots, and the translocation of metals from roots to shoots was restricted. Intercropping of V. zizanioides and S. rostrata did not show any beneficial effect on individual plant species, in terms of height, biomass, survival rate, and metal accumulation, possibly due to the rather short experimental period of 5 months.     

混凝土生态膜法污水处理工艺生物相及其水处理实验研究

研究了混凝土生态膜污水处理工艺的循环挂膜过程.综合考察了混凝土膜片表面生物膜的生长变化情况、细菌数量及其微型动物的组成演化.生物膜成熟以后,投加实际生活污水连续运行:COD的平均去除率为76.0%;BOD5平均去除率为94.9%,出水均小于8.00 mg/L;NH3-N的去处理效果明显,第5周达到54.1%,出水可达到广东省一级排放标准中的相关规定.     

特定小流域水质模型的选择

根据特定小流域的水文特点和实际要求，建立一个流域综合水质模型，它由三个子模型支持，即：河流水质模型、水库富养营化模型和非点源污染模型。本工作对河流水质模型（ＱＵＡＬ２ＥＵ）加以改进，使之适应Ｗ河的具体情况，并在ＱＵＡＬ２ＥＵ增加了模拟ＣＯＤ、网箱养鱼和底泥泛起的功能。完成了作了水源地的水库地的水库富营养化模型，解决了流域内农业耕作、污水灌溉等造成的非点源污染随降雨径流进入水体过程的模拟和计算，使之     

碱性及含硫化合物对十溴联苯醚热降解的影响

将十溴联苯醚（BDE-209）于400~600℃的温度范围内进行热降解,利用GC、GC/MS对产物种类及含量变化进行分析,讨论了温度、时间、碱性化合物和含硫化合物对BDE-209降解以及对溴代二噁英生成的影响.结果表明.温度和时间均是BDE-209热降解和生成溴代二噁英的重要影响因素;热降解40min时,450℃条件下溴代二噁英生成量最多;产物种类证实碱性化合物通过与BDE-209脱溴形成的HBr反应促进降解,且可抑制二噁英的生成;含硫化合物的添加同样促进BDE-209降解,抑制二噁英的形成,其详细的抑制机理有待进一步确定,BDE-209的降解反应有两种情况,即苯环上的脱溴反应和醚键的断裂反应.     

淋洗-抽提技术修复柴油污染土壤及地下水案例分析

以广东珠海某电镀行业企业发生柴油泄漏事件为例,采用异位修复抽提处置技术处理污染地下水,表面淋洗工艺处理污染土壤。泄漏点开挖区设置9个喷头,洒水量为1.3 m3/h,喷淋时间为2 h/d,泄漏点西面绿化带设置5个喷头,洒水量为0.7 m3/h,喷淋时间为9 h/d,淋洗水进入地下水后抽取至厂区污水厂处理,治理历时9个月,地下水石油类浓度降至0.3 mg/L以下,达到GB 5749—2006《生活饮用水卫生标准》中石油类标准限值。     

锡林郭勒草地产草量空间动态变化及影响因素分析

以内蒙古锡林郭勒盟为研究区,在陈世荣建立模型的基础上,明确2000—2010年产草量的空间分布及变化情况,从而反映研究区草地生长状况及空间格局的动态变化,并对相关影响因素进行分析。结果表明:(1)11年草地平均产草量为1.2×10~7 t,平均单产为601.97 kg?hm~(-2),整个研究时间序列中产草量在1.0×10~7 t—1.5×10~7 t波动变化;(2)草地产草量的地域性差异较明显,产草量空间分布情况为东部中部西部,其中中部及东部产草量变化较大,西部几乎无明显变化;(3)草地产草量受自然因素和人为因素的综合影响,其中降水量和载畜量是影响草地产草量的重要因素。     

非负载无定形态Mn-Ce催化剂的脱硝性能分析

以自制复配无机锰盐和分析纯六水合硝酸铈为原料,制备了非负载无定形态Mn-Ce催化剂,运用XRD,XPS,NH_3-TPD技术对其进行了表征,并对其脱硝活性进行了评价。结果表明:所制备催化剂的体相结构为高度无定形态;催化剂中的Mn和Ce元素主要以MnO_2和CeO_2的形式存在;催化剂表面有大量的化学吸附氧和弱酸位点,并表现出较好的NH_3吸附性能;该催化剂不仅具有较高的脱硝活性,而且还有较宽的活性温度范围,80~300℃的脱硝率均达90%以上。