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31.
对不同离子交换柱、淋洗体积、盐度、分离次数等一系列影响铜、锌纯化分离效果的条件进行了探讨,确定了环境样品(湖泊沉积物、植物和颗粒物)中铜、锌同位素测定时化学分离的最佳条件。采用AGMP-1(100～200目)阴离子交换树脂,以7mol/LHCl+0.001%H2O2、2mol/LHCl+0.001%H2O2、0.5mol/LHNO3作为淋洗液,分别在适当的体积接收淋洗液,可以有效地分离沉积物、植物和悬浮物等样品中的铜和锌。化学分离过程中Cu和Zn的回收率接近100%,同位素分馏在测试误差范围以内。将此方法应用于对红枫湖和阿哈湖水体悬浮物、植物和鱼类等样品中Cu、Zn的分离,经MC-ICP-MS测试后,准确获得了这些样品的Cu、Zn同位素组成。 相似文献
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样品经王水分解,硫脲提取,石墨炉原子吸收光谱法测定化探样品中的微量银。方法检出限为0.058 ng/mL;精密度(RSD,n=6)为0.8%～5.4%;回收率为94%～105%。方法经国家一级标准物质验证,测定结果与标准值相符。 相似文献
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Samples of snowpack leachate were collected over a 60 day period of the spring melt season in 1988 and 1989 at a 10 km2 upland catchment in the Cairngorm mountains of Scotland. These were analysed for major ions to assess snowpack chemistry dynamics through the spring and to assess the melt water influence on stream water chemistry. The data clearly show preferential elution of sulphate and nitrate over chloride and hydrogen over the other cations during the early melt of 1988. Following the addition of ions to the snow surface, either as snow or later in the season as rain, the elution sequence is reproduced. Comparison of leachate chemistry with stream chemistry samples taken at the basin outlet indicate that snow pack melt water contributes directly to stream water. The stream water chemistry signal is, however, noisy and the stream concentrations are considerably damped relative to the snowpack leachate. This is thought to be a consequence of differential melting within the catchment as the snowpack at lower altitudes is at a more advanced stage of melt and so holds fewer solutes and mixing with groundwater contributions. Temperature observations at different altitudes within the catchment support this interpretation. 相似文献
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为研究野外放射性污染物受雨、雪淋洗的程度,进行了模拟物的淋洗实验,结果初步表明有相当一部分放射性物质被淋出。这与现场调查的认识是一致的。 相似文献