二溴对甲偶氮甲磺光度法测定化妆品中铅量

长期接触含铅量高的化妆品易引起人体慢性铅中毒,使血液流通不畅,从而导致暗疮、色斑增多,皮肤干燥、发黄、松弛,衰老加快.目前测定化妆品中铅含量的国家标准方法有石墨炉原子吸收光谱法和双硫腙吸光光度法[1].     

氢化物发生-冷原子吸收光谱法测定化妆品中汞

介绍用氢化物发生-冷原子吸收光谱法在重铬酸钾-硝酸溶液存在下测定化妆品中汞的含量。方法空白值低、灵敏、准确、精密度好，特别适合于化妆品中汞的测定。     

微波消解-石墨炉原子吸收光谱法测定化妆品中痕量的铅

正化妆品具有清洁护肤、滋养健肤、修饰驻颜等作用,长期以来受到人们青睐[1-2]。化妆品中常被人为地添加入铅,从而达到美白的功效。铅是可在人体内蓄积的有毒金属,以无机铅中毒较为常见,长期接触会损害神经系统、消化系统、造血系统和肾脏[3-5]。因此,铅含量作为化妆品中的一个重要卫生项目,有着非常严格的限量要求[6]。目前测定化妆品中铅的常用方法有分光光度法、原子吸收光谱法、电感耦合等离子体原子发射光     

微波消解–石墨炉原子吸收法测定化妆品中的铅

建立了微波消解–石墨炉原子吸收光谱法测定化妆品中铅的方法。探讨了样品前处理条件、基体改性剂的选择和优化、石墨炉升温条件等对测定结果的影响。在优化的试验条件下,铅的质量浓度在0~100 ng/mL范围内与吸光度具有良好的线性关系,线性相关系数r=0.9991,检出限为0.33 ng/mL。用该法对5种化妆品中的铅进行测定,加标回收率在95.0%~106.1%之间,测定结果的相对标准偏差不大于3.6%。该方法可应用于化妆品中痕量铅的分析。     

电感耦合等离子体原子发射光谱法测定化妆品中硼酸及硼酸盐含量

化妆品样品采用微波消解法处理,用电感耦合等离子体原子发射光谱法测定样品溶液中的硼酸和硼酸盐含量。选择钇元素作为内标元素,选择波长249.678nm谱线作为硼的分析线。硼的质量浓度在1.0mg.L-1以内与其发射强度呈线性关系,方法的检出限(3s)为0.002mg.L-1。方法用于分析了几类化妆品样品,回收率在95.2%～100%之间,测定值的相对标准偏差(n=10)在2.4%～3.8%之间。     

微分电位溶出法测定化妆品中的镉

化妆品中镉的测定方法主要有双硫腙吸光光度法、原子吸收分光光度法。前者手续繁杂后者价钱昂贵因此未能广泛应用。本文样品中镉以离子状态存在于酸性溶液中,于—0.62V(vs.SCE)处有一灵敏的溶出峰,其峰高与含量呈正比,可用标准曲线法进行定量测定。     

微波消解法测定化妆品中铅砷汞

化妆品在硝酸和过氧化氢溶液中 ,在微波电场的作用下 ,使分子产生高速的碰撞和摩擦而产生高热 ,在加压的条件下 ,由于酸的氧化及活性增加 ,可使化妆品在较短的时间内被消解 ,化妆品中铅砷汞以离子的状态存在于试液中。1　试验部分1.1　试剂与仪器氯化亚锡溶液 :2 0 0ｇ·Ｌ-1铅砷汞标准溶液的配制方法见ＧＢ7917.1.2 .3- 87ＭＫ Ⅱ型光纤压力自控微波溶样系统 ,6 0ｍｌ聚四氟乙烯消化罐 (上海新科微波技术应用研究所研制 )岛津ＡＡ 6 80 0型原子吸收光谱仪ＹＹＺ 2型冷原子测汞仪1.2　分析方法[1～ 3 ]称取均匀样品 0 .2～ 0 .5ｇ置于聚四氟…     

消解方法对电感耦合等离子体原子发射光谱法测定化妆品中锑镉铬钕的影响

比较了不同前处理方法(湿法消化、湿法回流消化和微波消化)对电感耦合等离子体原子发射光谱法测定化妆品中锑、镉、铬和钕的影响,并考察了氢氟酸对粉类化妆品消解的作用。结果表明:湿法回流消化和微波消化法适合于不同种类样品的前处理。氢氟酸可充分破坏二氧化硅晶格,是粉类化妆品中测定锑所必须的;但稀土元素与氢氟酸会生成难溶氟化物沉淀,故钕的测定不宜加入氢氟酸消解。通过充分回流消化或微波消化,在不加入氢氟酸破坏二氧化硅晶格的情况下也可以将粉类化妆品中的镉、铬和钕充分提取出来。方法的加标回收率在80.3%~118.5%范围,相对标准偏差(n=11)在4.25%~6.09%之间。     

微波消解-ICP-OES法同时测定化妆品中Pb、As、Hg

采用微波消解ICP-OES法同时测定化妆品中Pb、As、Hg的含量,并对ICP-OES法测定化妆品消解液时分析线的选择,入射功率、泵速的影响,以及进行检测限、准确度、精密度的研究.用微波消解ICP-OES法测试化妆品中重金属检测结果快速准确.     

火焰原子吸收法测定化妆品中的铬

采用火焰原子吸收分光光度法测定了兰州市的一些市售化妆品中铬的含量。结果表明,方法检测限(3σ)为0.003 mg/L,回收率在94%~105%之间,相对标准差小于1.3%,方法简便快速;市售多数化妆品中的铬含量超过国家标准,须引起人们的注意。     

Derivative hydride generation atomic absorption spectrometry and determination of lead traces in waters

Fundamentals of derivative hydride-generation atomic absorption spectrometry (DHGAAS) are described. A linear relationship was obtained between the derivative absorbance and the concentration of analysis in a sample. The new DHGAAS method was applied to the determination of traces of lead in water. The conditions affecting the derivative absorbance of lead were evaluated and optimized. The detection limit and sensitivity of the proposed method were 26 times and 8.8 times better, respectively, than those of conventional hydride-genera-tion atomic absorption spectrometry. The characteristic concentration (for a derivative absorbance of 0.0044) and detection limit (3sigma) for lead were 0.017 and 0.096 ng mL(-1), respectively, for a 2 mV min(-1) sensitivity range setting. The recovery range was 92.5-103%.     

In-situ concentration and determination of mercury by graphite furnace atomic absorption spectrometry with Pd-Rh as the chemical modifier

A method has been proposed for the determination of mercury by cold vapor generation graphite furnace atomic absorption spectrometry (CV-GFAAS) with Pd-Rh as coating and chemical modifier. The trapping efficiency for mercury with Pd-Rh was higher than with Pd alone. The characteristic mass of the method, which gives an integrated absorbance of 0.0044 s, was found to be 55 pg and the absolute detection limit (3 σ) of 37 pg was obtained with the proposed modifier. The method was successfully applied to the determination of mercury in standard reference water samples, wastewater samples and cosmetics with a recovery range of 95–104%. Received: 10 April 1998 / Revised: 20 August 1998 / Accepted: 23 September 1998     

石墨炉原子吸收光谱法测定航空铜合金中微量铅

用硝酸和氢氟酸溶解铜合金,用石墨炉原子吸收光谱法直接进行测定。为了消除基体元素及其他共存元素的干扰采用标准加入法进行测定,并对最佳的测量酸度进行讨论。方法用于航空铜舍金中铅的测定,加标回收率为90．5%-113．0％,基本消除干扰,方法简单、快速。     

In-situ concentration and determination of mercury by graphite furnace atomic absorption spectrometry with Pd-Rh as the chemical modifier

A method has been proposed for the determination of mercury by cold vapor generation graphite furnace atomic absorption spectrometry (CV-GFAAS) with Pd-Rh as coating and chemical modifier. The trapping efficiency for mercury with Pd-Rh was higher than with Pd alone. The characteristic mass of the method, which gives an integrated absorbance of 0.0044 s, was found to be 55 pg and the absolute detection limit (3 σ) of 37 pg was obtained with the proposed modifier. The method was successfully applied to the determination of mercury in standard reference water samples, wastewater samples and cosmetics with a recovery range of 95–104%. Received: 10 April 1998 / Revised: 20 August 1998 / Accepted: 23 September 1998     

环境水样中痕量铅的中孔分子筛Al-MCM-41分离富集-火焰原子吸收法测定

建立了中孔分子筛Al-MCM-41分离富集-火焰原子吸收光谱法测定水样中痕量铅的新方法。采用扫描电镜(SEM)、红外光谱(IR)等检测方法对自制的中孔分子筛Al-MCM-41吸附材料进行了表征,优化了中孔分子筛Al-MCM-41对试液中痕量铅的吸附和解吸条件。在pH5.5时,室温振荡20 min,中孔分子筛Al-MCM-41能定量、快速吸附水中的痕量Pb2+,其静态饱和吸附容量为2.5 mg/g。吸附在中孔分子筛Al-MCM-41上的Pb2+可用0.2 mol/L EDTA完全洗脱。其他金属离子共存不影响铅的测定。洗脱铅后的吸附材料经再生可循环使用10次以上。Pb2+的线性范围为0.5~30 mg/L,富集后方法检出限(3σ)为0.05μg/L,对5 mg/L的Pb2+溶液平行测定11次,相对标准偏差为1.2%,加标回收率为98%~104%。该方法用于环境水样中铅的测定,结果满意。     

固体进样-石墨炉原子吸收光谱法直接测定玉米中的铅

建立了一种直接固体进样-石墨炉原子吸收光谱法测定玉米中铅的方法。方法的相对标准偏差为4.8%~11.3%(n=9),铅的检出限为0.0062ng,测定结果与国标法一致。与湿法消解方法相比较,本方法样品不用进行化学前处理而直接测定,避免了样品的稀释以及试剂的交叉污染带来的分析误差。     

微波灰化-氢化物发生-原子荧光光谱法测定原油和燃料油中的铅和砷

探讨了使用微波灰化技术消化原油和成品油样品,并使用氢化物发生-原子荧光光谱法测定其中铅和砷的含量.研究了铅测定的灰化保护剂和砷测定的灰化助剂,并优化了仪器工作条件和实验条件.该方法测定原油和重油中铅的平均回收率分别为96.8%和96.7%,相对标准偏差分别为1.03%和0.93%;测定原油和重油中砷的平均回收率分别为90.0%和90.3%,相对标准偏差分别为2.39%和2.63%.     

热喷雾进样火焰原子吸收光谱法测定河水中的铅

铅被广泛应用于蓄电池、建筑材料、电缆外套等工业生产中,是造成河水污染的主要原因。铅为生物体有害元素,当其被人体组织吸收后,分布予肝、肾、肺、脑中,损害骨髓造血系统和神经系统。在环境检测中铅是必须检测的元素之一。火焰原子吸收光谱法具有仪器简单、操作方便、抗干扰能力强、稳定性好等特点,但由于雾化效率低和灵敏度低,不能直接用于测定样品中的低含量铅。     

Flame atomic absorption spectrometric determination of lead in waste water and effluent after preconcentration using a rapid coprecipitation technique with gallium phosphate

A determination method for lead in waste water and effluent was studied using flame atomic absorption spectrometry after preconcentration of lead by the rapid coprecipitation technique with gallium phosphate. Lead ranging from 0.5 to 50 microg was quantitatively coprecipitated with gallium phosphate from 100-150 mL sample solution (pH approximately 5). The presence of gallium phosphate did not affect the atomic absorbance of lead. Since the concentration of gallium in the final sample solution is also measurable by flame atomic absorption spectrometry at 250.0 nm without further dilution, the rapid coprecipitation technique, which does not require complete collection of the precipitate, becomes possible using a known amount of gallium and measuring the concentrations of both lead and gallium in the final sample solution by flame atomic absorption spectrometry. The 32 diverse ions tested gave no significant interferences in the lead determination. The method proposed here is rapid and has good reproducibility.