研究发现，同时在样品溶液中加入0.04%DDTC、还原剂溶液中加入0.2%DDTC 将极大地增强金挥发物的发生效率。将一个带调节阀的转子流量计串联在屏蔽气或载气气路中间，流量计量程为0～1200 mL/min，进行手动调节，解决了计算机自动调节范围不满足屏蔽气和载气实验条件的问题。结果表明，载气流量为100 mL/min，屏蔽气流量为700 mL/min 时可获得最佳的信号强度和信噪比。通过对仪器工作参数和反应体系参数进行优化，使标准溶液检测信号较原子吸收法提高10倍以上。方法用于地质样品中金的检测，结果与火焰原子吸收法相吻合。同时，通过比较 DDTC、聚醚型软质聚氨酯泡沫和硫脲分子结构，推测其反应机理指导寻找新的金增敏剂。%It is found that the present of 0.04% DDTC in sample solution and 0.2% DDTC in reductant solution at the same time can greatly enhance generation efficiency of volatile species of Au.The problem that computer automatic adjustment range does not meet the experimental conditions of shielding gas or carrier gas can be solved by connecting a rotor flowmeter with control valve in series in shielding (or carrier) gas path.The measuring range of the rotor flowmeter is 0~1 200 mL/min,and it can be adjusted manually.The result shows that the optimal signal intensity and signal-to-noise ratio can be gotten when carrier gas flow rate is 100 mL/min and the shield gas flow rate is 700 mL/min.Signal is above ten times stronger than AAS method after optimizing the parameter of instrument and chemical vapor generation.The method is used in determination of gold of ore sample,the results are consistent with those gotten by flame AAS.The reaction mechanism can be assumed by comparing molecule structure of DDTC,polyurethane foam and thiourea molecules,which will help find new gold sensitizations.
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