炎性因子在大气细颗粒物(PM2.5)心血管毒性中的作用

PM2.5染毒心血管内皮细胞24h后,提取内皮细胞中的mRNA,通过逆转录多聚酶链式反应(RT-PCR)技术及电泳的方法,确定PM2.5染毒前后心血管内皮细胞中IL-4、嗜酸性粒细胞活化趋化因子(extaxin)相对含量的变化.结果表明,随着大气PM2.5染毒浓度的增加,0.05,0.20mg/mL染毒组心血管内皮细胞中IL-4和extaxin mRNA表达产物的相对含量显著增高,说明IL-4、extaxin等I型变态反应相关炎性因子在PM2.5的心血管毒性中可能起一定作用.     

土壤中有效态稀土元素提取剂的选择

 通过0.01mol/LHCl，0.05mol/LHCl，1.0mol/L NH₄Oac（pH7.0），1.0mol/LNH₄NO₃（pH7.0），1.0mol/LHOAc/NH₄Oac（pH4.8），1.0mol/LNH₄Cl（pH7.0）6种提取剂对20种土壤中有效态稀土元素测定结果的比较，以及将测定结果同土壤特性、土壤中稀土元素形态进行相关分析，并通过黑麦草土培试验进行了生物评价，确定了1.0mol/LNH₄NO₃（pH7.0）为提取土壤中有效态稀土元素的最佳提取剂．     

区域水体中汞的质量平衡与生物地球化学循环

本文是几年来在蓟运河下游对汞的地球化学行为进行综合研究的结果.通过箱式模型的方法,利用质量平衡公式对各流量进行定量计算,结果表明:排入河流的汞,绝大部分很快沉积入水底沉积物中;而存在于河水中的汞,水迁移是最主要的,气迁移很少,生物迁移微乎其微.本文提出了水体中汞的生物地球化学循环模型.汞循环途径主要有两条:无机汞被生物甲基化后的生物小循环和汞在水体与大气之间的地球化学循环.这两种循环主要是由沉积物中的无机泵被生物转变成甲基汞或元素汞之后完成的.因此,存在于沉积物中的无机汞的甲基化能力与转化为元素汞的量,决定了这两种循环过程的汞通量问题.     

东南沿海火山、侵入杂岩同位素年代学

本文运用同位素年代学方法对东南沿海火山、侵入杂岩进行系统研究。认为火山活动起止时间因地而异,粤东为180—75Ma;渐、闽为135—105Ma,东西两区也有差别。发现粤东高基坪群下群存在180—170Ma的早侏罗世火山岩。全区火山活动可划分为七个旋回。火山岩与侵入岩同时、同源、同空间和同步迁移。火山活动先由南向北,再由北向南逆转;东西方向由大陆向海洋推移演化。     

江苏九龙口湿地生态旅游的开发

九龙口是江苏里下河地区的一处湿地自然保护区，也是江苏省风景名胜区。这里生态环境独特，自然风光优美，具有发展生态旅游的良好前景。本文分析了九龙口湿地生态特点、开发优势，提出了生态旅游的发展设想。     

用加速溶剂提取仪提取污染土壤中的有机氯农药

研究加速溶剂萃取对土壤中有机氯农药的提取效果,并与索氏提取法进行比较。结果表明,加速溶剂萃取对土壤中滴滴涕的回收率明显高于索氏提取,对土壤中BHC的提取能力与索氏提取相当。用该方法测定了天津污灌区和非污灌区土壤样品中的有机氯农药残留量。结果表明,α-BHC、β-BHC、δ-BHC、γ-BHC、p,p’-DDE、p,p’-DDD、p,p’-DDT、o,p’-DDT的检出率为100％,这些有机氯农药在污灌旱地和稻田地的残留量分别为7．5－71．1ng/g和3．0－16．5ng/g。非污灌的旱地中有机氯农药的残留量为3．1－17．6ng/g。     

农药在大棚蔬菜上的残留消解

通过对６种农药在７种大棚作物上的共１４次农药残留消解试验，及与露地作物所作的比较表明，除粉锈宁在大棚草莓上的消解外，农药在大棚蔬菜上的残留消解速度要慢于露地蔬菜，大棚空间农药沉降于蔬菜，是消解慢的重要原因，而环境条件对消解的影响程度还需进一步研究。该文指出，消解慢和大棚空气中浓度高；是大棚生产中两个突出的农药污染问题，前者导致上市大棚蔬菜的农药超标率高，后者为农事操作人员带来了恶劣的工作条件，需采     

石墨炉原子吸收光谱法测定土壤中的镉

采用微波消解系统处理土壤样品,可以大大减少消化试剂的用量及样品的处理时间.石墨炉原子吸收法测定土壤中的镉,以磷酸氢二铵和硝酸镁作混合基体改进剂,可提高灰化温度,消除基体干扰.方法简便、快速,准确度高.镉的测定结果相对标准偏差为2.1%～4.5%;检出限为0.007mg/kg.     

Effect of phosphate fertilizer application on phosphorus (P) losses from paddy soils in Taihu Lake Region. I. Effect of phosphate fertilizer rate on P losses from paddy soil

A field plot study was conducted on two types of paddy soils in the Taihu Lake Region, during the rice season of year 2000 in order to assess phosphorus (P) losses by runoff and vertical leaching, which are considered the two main pathways of P movement from paddy soil into its surrounding water course. Commercial NPK compound fertilizer and single superphosphate fertilizer were applied to furnish 0, 30, 150, and 300 kg applied P ha m(-2). The experiments consisted of three replicates of each treatment in Changshu site and four replicates in Anzhen site, with a plot size of 5 x 6 m2 in a randomized block. Results revealed that the average concentration range for total P (TP) in runoff was 1.857-7.883, 1.038-5.209, 0.783-1.255 and 0.572-0.691 mg P l(-1) respectively for P300, P150, P30 and P0 in Anzhen, while it was 2.431-2.449, 1.578-1.890, 1.050-1.315 and 0.749-0.941 mg P l(-1) respectively in Changshu. In all treatments, particulate P (PP) represented a major portion of the TP lost in runoff, it was 80% in Anzhen, and it was even more (>90%) in Changshu. Phosphate fertilizer treatments significantly affected P concentrations and P loads in the runoff. The mean concentration and average seasonal TP load from the P150 plots were 1.809 mg P l(-1) and 395 g P ha m(-2) season(-1) respectively, and lower than that from the P300 plots (2.957 mg P l(-1) and 652 g P ha m(-2) season(-1)). These were obviously higher than from the P30 (0.761 mg P l(-1) and 221 g P ha m(-2) season(-1)) and P0 (0.484 mg P l(-1) and 146 g P ha m(-2) season(-1)) respectively. There was no significant difference found between the P30 and the P0 in both sites. Under usual P application rate, there were total 31.7 and 20.6 tones P removed by runoff from permeable (Anzhen site) and waterlogged (Changshu site) paddy soils in the southern Jiangsu region (major part of the TLR) in the rice season of the year 2000. But if the P application rate is unusual high, or the Olsen P in soil accumulates to above a certain level, then this could sharply increase in the future. The average concentration of molybdate reactive phosphorus (MRP) in the vertical leachate from the four different P treatments ranged from 0.058 to 0.304 mg P l(-1) in Anzhen and from 0.048 to 0.394 mg P l(-1) in Changshu. P application rate significantly affected the MRP concentration at each depth in both sites, except for the 90 cm in Anzhen. The average MRP loads during the rice season moved by vertical leaching from the four treatments ranged from 163 to 855 g P ha m(-2) season(-1) in Anzhen and 208-1,825 g P ha m(-2) season(-1) in Changshu. Vertical leachate movement does not necessarily mean that it moves towards surface water and contaminate the watercourses in this flat plain paddy soil region, it does, however, imply that P can move down from surface layers of soil to deeper levels.     

水资源的持续开发和利用

随着人品的增长和经济的发展,越来越多的国家正面临着严重的水危机、水质的恶化和水生态系统的破坏使许多国家的淡水供应出现危机,所以水资源必须得到保护和合理的开发。本文探讨了全球水资源的短缺及其原因,并提出了解决水资源短缺的途径。