用聚焦式X射线荧光光谱仪测定液体化妆品中的铅、砷，以及浴盐中氯的含量，并提出了一种新的进样方法——瓶口贴膜法。对液体样品可直接进样分析，对一些固体样品，如浴盐，需经灼烧灰化后以1∶5的质量比溶于水中再行测定。方法中选用体积为2 mL，且其瓶口高度误差在0.2 mm以内，具有带孔瓶盖的小瓶作为进样瓶。将液体样品装入瓶中，使液面略超瓶口，随即将2.5 μm聚酯（Mylar）膜覆盖于上，拧上瓶盖并使膜紧贴液面，保持平整。将进样瓶置于样品台上，移动样品台，用激光对焦，采用扩展康普顿散射模型进行基体校正和校准曲线拟合。结果表明：常量氯元素的测定值的相对标准偏差（n=11）为0.65%；痕量铅和砷的测定值的相对标准偏差（n=11）均小于5.0%，其检出限分别为3.0，1.0 mg·L^-1。测定结果均与标准方法测定结果相符。

The focusing X-ray fluorescence spectrometer was used to determine Pb and As in liquid cosmetics and Cl^- in bath salt, and a new method of sample introduction-film mounted sample bottle method was proposed. Liquid samples could be introduced directly for analysis, but for solid sample, e.g. bath salt, it should be ignited, ashed and dissolved in water by the mass ratio of 1 to 5, and the solution was then used for analysis. As described in the method, small bottles having its volume of 2 mL, keeping the deviation of height of its bottle mouth within 0.2 mm and attached with holed caps were selected for use as sample introduction bottles (abbre. as SIB). Liquid sample (or solution) was transferred into the SIB with the liquid surface a little higher over the bottle mouth. A piece of 2.5 μm Mylar film was mounted on the liquid sample, and the cap was screwed on, keeping the Mylar film to adhere tightly to the liquid surface and to be level and smooth. The SIB was then moved onto the sample tab and focused with laser. The extended Compton scattering model was used for matrix correction and fitting of calibration curve. As shown by the results, RSD (n=11) of the major contents of chlorine was 0.65%. RSDs (n=11) for traces of Pb, As were both less than 5.0%, and detection limits for Pb and As were 3.0, 1.0 mg·L^-1, respectively. The results obtained by this method were consistent with those found by the standard method.