固相微萃取-气相色谱-质谱法测定饮用水中土嗅素和2-甲基异茨醇

采用固相微萃取法富集,气相色谱-质谱联用法定性和定量测定饮用水中致嗅物质土嗅素和2-甲基异茨醇。研究并讨论优化了纤维头的类型、盐的种类和浓度、温度、萃取时间等因素对异味化合物萃取量的影响。土嗅素和2-甲基异茨醇的检出限分别为1.02、2.13 ng/L,相对标准偏差分别为4.96%、7.74%。2种异味化合物在5~1 000 ng/L的范围内线性关系良好,相关系数均大于0.985。因此,用该方法能够很好地分析水中痕量的异味化合物。     

Impacts of two best management practices on Pb weathering and leachability in shooting range soils

This study investigated the impacts of two best management practices (BMPs) recommended by US Environmental Protection Agency on Pb weathering and leachability in shooting range soils. The two BMPs included replacing soil berm with sand berm and periodically removing bullets or shot from a berm. A column experiment corresponding to the first BMP was conducted by mixing the bullets with sand/soil, or placing bullets on the surface of sand/soil. After a 16–18-week incubation under high or low rainfall simulations, total Pb concentrations in sand were lower than that in soil. Total leachable Pb in sand (8.48 and 5.52 μg?kg^?1) was also lower than that in soil (60.0 and 30.4 μg?kg^?1) when bullets were mixed with sand/soil; however, they were comparable when bullets were placed on the sand/soil surface. These results indicate that lower Pb concentration in the sand than in soil may be attributed to reduced weathering of bullets. Mechanical removal of Pb bullets in the field transferred Pb from large to finer particles, increasing total Pb in the soil (<2 mm) from 2,170 to 5,000 mg?kg^?1. In contrast, mechanical removal of Pb shot effectively reduced the shot in the soil by 86–92 %. Thus, we concluded that, while replacing soil berm with sand berm can slow down Pb weathering, it may increase Pb leachability in the long term. Removal of Pb bullets and Pb shot can be effective, but caution needs to be exercised to minimize the adverse impacts, especially in pistol/rifle ranges because of increased total Pb content in the soil.     

基于OMI数据的中国臭氧总量时空分布特征

基于OMI数据产品OMITO3e,提取了中国2005—2011年臭氧总量信息,并对其空间分布和时间演变特征加以分析。研究结果表明:在空间上,中国臭氧总量呈现北高南低、东高西低的特征,峰值出现在东北地区,夏秋季节在青藏高原存在明显的臭氧低谷;在纬度上,中国东北部臭氧总量纬向偏差为正,在其他区域为负;在时间上,中国臭氧总量呈现明显的季节变化特征,冬春季节高,夏秋季节低,最大值多出现在3月,最低值多出现在10月。     

液液萃取-气相色谱-质谱法同时测定饮用水中的酞酸酯、百菌清和联苯胺

建立了液液萃取-气相色谱-质谱（LLE -GC/MS）同时测定饮用水中的6种酞酸酯类化合物、百菌清和联苯胺的方法。选用3种有机溶剂进行萃取,筛选出回收率高、操作简单的前处理方法,萃取后经气相色谱-质谱分析。方法表明：8种物质线性良好,相关系数为0．9978～0．9995,用二氯甲烷萃取回收率最佳,回收率在90．1％～118％之间,相对标准偏差在0．24％～7．21％之间。     

兰州市空气污染物的变化规律与特征

论述了兰州市 1 993～ 1 996年间 ,室内外空气污染物 ,特别是一些非常规监测指标 ,如 PM1 0 、PM2 .5～ 1 0 和 PM2 .5 的污染规律和分布特征。结果表明兰州市仍以尘污染为主 ,PM1 0 在 TSP中平均占 3 3 %左右 ,而 PM2 .5 占了 PM1 0 的大部分     

兰州市气溶胶中金属与非金属元素的污染规律

通过对兰州市空气飘尘中粗、细颗粒物上化学元素的分布规律与特征的分析 ,指出了细颗粒物 (PM2 .5 )是一些有毒有害元素的主要携带者。这是可以在肺泡沉积 ,并能直接进入血液循环 ,对人体产生危害的重要部分     

兰州市空气污染对儿童及其父母呼吸系统健康的影响

叙述了居住环境对儿童和儿童父母亲呼吸系统健康影响的研究结果。揭示了儿童对空气污染所引起的呼吸系统疾病的急性反应较成人更敏感。吸烟合并空气污染更能损害人的健康     

还原-光度法测定空气中二氧化硫

在 pH 5 0～ 6 2、甲醛 -邻苯二甲酸氢钾介质和沸水浴中 ,微量二氧化硫能迅速还原三价铁为二价铁 ,使生成的邻菲口罗啉 -铁 (Ⅱ )铬合物量增加 ,导致溶液颜色变深 ,据此测定二氧化硫的含量。方法测定范围为 0mg/L～1 4mg/L ,检测限为 0 4mg/L。用于测定空气中二氧化硫 ,获得了满意的结果     

Distribution of endocrine disruptors in the Mondego River estuary, Portugal

Recent studies in the Mondego River estuary demonstrated signs of pollution in the area, but the nature of the contamination remains unexplored. Because there seems to be any studies in that zone checking for the simultaneous presence of xenoestrogenic endocrine disrupting compounds, either of animal (estradiol and estrone), vegetal (daidzein, genistein and biochanin A), pharmaceutical (17alpha-ethynylestradiol) or industrial (bisphenol A, 4-octylphenol, 4-nonylphenol) origins, the main objective of this study was to investigate their presence, in every year season and at eight points along the estuarine gradient. For this propose, water samples (2 L) were collected in high and low tides, preconcentrated in the Oasis HLB cartridges and cleaned in silica cartridges before their analysis by HPLC-DAD and GC-MS. The current data showed the absence of contamination by animal or pharmaceutical estrogens and by alkylphenols, but demonstrated the presence of high levels of phytoestrogens (up to 1.1 mug/L) and of bisphenol A (up to 880.0 ng/L). Because these two chemicals existed in high environmental concentrations in the most upstream sampling station, and taking in account that these pollutants may additively contribute to endocrine disruption, namely on fish, it was concluded that at least this particularly area of the Mondego estuary deserves continuous monitoring programmes.