微波消解氢化物发生-原子荧光光谱法测定罐头食品中汞和锡

建立了一种微波消解、氢化物发生-原子荧光光谱法同时测定罐头食品中汞和锡的方法。研究了测定汞、锡时介质的酸度和硼氢化钾的用量对汞、锡测定的影响。优化了样品消解和测定的条件,采用硫脲-抗坏血酸为掩蔽剂,以酒石酸为载流,消除了影响锡测定的干扰因素。汞和锡的检出限、相对标准偏差、回收率分别为:0.005μg.L-1和0.20μg.L-1;5.0%~6.5%和4.0%~7.3%;93.0%~101.0%和92.5%~94.0%。     

纳米二氧化钛分离富集-原子荧光光谱法测定植物样品中的痕量汞

随着汞（Hg）污染研究的不断发展,对检测数据准确度的要求也不断提高。原子荧光光谱法（AFS）自诞生以来一直以其独特的优点作为测汞的主流方法,然而部分植物样品中含量极低的汞难以被准确检测,适宜的分离富集方法很少。本文采用纳米二氧化钛（TiO2）动态分离富集-原子荧光光谱法测定植物样品中的痕量汞,对分离富集条件进行了系统研究,最优条件为:粒径25nm、过柱溶液pH中性、硝酸为洗脱液用酸、硝酸体积分数5%、洗脱液体积30mL。在此基础上建立了汞的检测方法,方法检出限0.27ng·g-1,精密度（RSD/%）7.2%,并对国家一级标准物质GBW10014a（圆白菜）、GBW10015a（菠菜）进行检测,测定值均符合参考范围。     

氢化物发生-原子荧光光谱法同时测定食品添加剂碳酸钙中的砷和汞

应用氢化物发生-原子荧光光谱法同时测定食品添加剂碳酸钙中的砷和汞,并对样品中的主要成份及共存元素可能对检验结果的影响和实验条件进行了研究.结果表明,加入硫脲-抗坏血酸溶液后,碳酸钙中主要成份钙及可能存在的共存元素铁、铅、镉、铜、锑、硒、锡、铬、锌等不干扰砷和汞的测定.方法检出限为砷0.0124 μg/L,汞0.0009μg/L,回收率为砷101.8%～102.2%,汞102.5%～106.0%.精密度为砷0.37%,汞0.95%.建立的氢化物发生-原子荧光光谱法同时测定食品添加剂碳酸钙中砷和汞的分析方法能满足日常检验的要求.     

原子荧光光谱法测定镉锭中锡的含量

采用氢化物发生-原子荧光光谱法测定镉锭中锡含量,研究了基体镉对锡的干扰及消除方法,优化了氢化物的发生条件,建立了镉锭中锡含量的快速分析方法。实验证明,原子荧光光谱法对锡的检出限为0.08mg/kg,回收率为99.0%～104.0%,方法准确、可靠,用于日常样品分析,取得了很好的效果。     

流动注射氢化物发生双道原子荧光同时测定水中汞和硒

环境水样中汞和硒的测定,文献提出汞的测定方法有冷原子吸收光谱法、原子荧光光谱法和双硫腙比色法,而硒为原子荧光光谱法和石墨炉原子吸收光谱法。本文用双道原子荧光光谱仪同时测定水中汞和硒,方法更为简便快速,准确可靠。     

冷蒸汽-原子荧光光谱法测定水样中3种形态的汞北大核心CSCD

汞在环境中的迁移和毒性,随其形态不同而不同。仅测定其总量的方法已不能适应汞化学的深入研究[1],对形态汞的测定,难点在测定前的化学处理[2]。本工作在文献[1-6]的基础上,提出了冷蒸汽发生-原子荧光光谱法测定水样中3种形态汞（无机汞、有机汞和总汞）,以应对各种环境影响评价的不同要求。1试验部分1.1仪器与试剂WGYSIA型数字原子荧光测汞仪,7663型远红外辐射干燥箱,1.0mL和10μL微量进样器。     

冷原子蒸气发生-原子荧光光谱法测定尿中汞

采用冷原子蒸气发生-原子荧光光谱法测定尿中的汞。尿样加入溴化剂处理后,直接用冷原子蒸气发生-原子荧光光谱法测定汞的含量。汞的质量浓度在0.15~10.0μg·L-1范围内呈线性,检出限(3s)为0.15μg·L-1。方法用于质控样品的分析,测定值与认定值相符,测定值的相对标准偏差(n=6)在2.8%~3.8%之间。应用此方法对实样进行测定,结果与冷原子吸收光谱法的测定结果相符。     

微波消解一氢化物原子荧光光谱法测定罐头食品中锡

为建立微波消解-氢化物原子荧光光谱法测定罐头食品中锡含量的方法。样品在HNO3＋HC1或HN03＋HCl＋H2O2体系中经微波消解处理后,以硫脲-抗坏血酸混合液作预还原剂,用氢化物原子荧光光谱法测定罐头食品中锡。结果表明,在优化的条件下,锡质量浓度在0～100μg／L范围内线性关系良好,相关系数为0．9998,方法最低检出限为0．067mg／kg,加标回收率在99．7％～108．3％之间,方法变异系数为2．67％（n=6）。该法具有准确度高、精密度好、灵敏快速且安全环保等优点,适用于罐头食品中锡的测定。     

原子荧光光谱法测定大米中的汞

以氯化亚锡为还原剂,结合SYG-Ⅱ型智能冷原子荧光测汞的技术结构特点,研究了原子荧光光谱法对大米中汞的测定。汞标准浓度在0～2.0μg/L范围内与荧光强度具有良好的线性关系,相关系数为0.9997。该方法测定结果的相对标准偏差为3.06%(n=10),检出限为0.02mg/kg,加标回收率为90%～108%。     

原子荧光光谱法测定皮革中9种重金属元素的含量

皮革样品经硝酸-高氯酸（4+1）混合酸湿法消解后,用氢化物发生-原子荧光光谱法测定其中砷、锑、汞、铅和镉的含量;样品经干法灰化后,用火焰原子荧光光谱法测定其中铬、钴、铜和镍的含量。对各元素的稀释介质、还原剂和仪器工作条件作了详细的叙述。9种元素的质量浓度与吸光度分别在一定的范围内呈线性关系;砷、锑、铅、钴和镍的检出限（3S/N）为0.5 mg·kg^-1,汞、镉和铜的检出限（3S/N）为0.05 mg·kg^-1,铬的检出限（3S/N）为5.0 mg·kg^-1。应用此法分析了皮革样品,以标准加入法做回收试验,回收率在89.2%～106%之间。     

氯化亚锡还原-原子荧光光谱法测定银精矿中汞

建立了原子荧光光谱法测定银精矿中汞的分析方法。试样经盐酸、硝酸溶解,在盐酸介质中,以盐酸(5%)为载流,氯化亚锡(200g/L)溶液为还原剂,用原子荧光光谱法测定银精矿样品中汞的含量。对仪器的最佳工作条件、还原剂的种类和浓度、样品溶样方式、共存元素的干扰等各方面进行了详细研究。结果表明,方法的相对标准偏差为3.1%~9.1%,与冷原子吸收光谱法测定结果相吻合。方法的准确度和精密度均能满足银精矿样品的检测需求,值得推广使用。     

Sensitive determination of gaseous mercury in air by cold vapour atomic fluorescence spectrometry after amalgamation

A method was developed for the determination of mercury in air, using preconcentration by amalgamation on gold absorbers followed by measurement by atomic fluorescence spectrometry (AFS). The system has a detection limit of ca. 2.0 pg and the precision is in the range 5–10% (relative standard deviation). The accuracy was confirmed by comparison with cold vapour atomic absorption spectrometry. The method was applied to the determination of gaseous mercury in both indoor and outdoor air. As a result of the sensitivity small sample volumes can be analysed and only short sampling times are required. The method is thus suitable for continuous monitoring of mercury and for the fast and reliable determination of gaseous mercury in the atmosphere, even at background levels.     

氧弹燃烧–原子荧光光谱法测定煤中汞含量

建立氧弹燃烧–原子荧光光谱法测定煤中汞含量的方法。用氧弹燃烧分解样品,汞释放后以硝酸溶液吸收,以0.5 g/L硼氢化钾溶液作为还原剂,体积分数5%的硝酸溶液为载流液,用原子荧光光谱法定量测定。方法检出限为0.02μg/kg,对标准物质GBW 11156(标准值0.32μg/g)进行平行测定,测定结果的平均值为0.318μg/g,相对标准偏差为7.3%(n=6),加标回收率为91.5%~106.5%。该方法简单、干扰少,准确度和精密度良好,可用于煤中汞的测定。     

王水消解-冷原子吸收光谱法测定土壤中汞

为了寻求一种更加适宜测定土壤中汞含量的测试方法,将检出限低、精密度高的冷原子吸收光谱法与便捷、高效的王水水浴消解土壤处理方式相结合,建立了王水消解-冷原子吸收光谱法测定土壤中汞。通过测定方法的线性相关性、方法检出限、准确度、精密度、加标回收率,并与原子荧光光谱法进行对比实验来评价该方法的有效性。王水消解-冷原子吸收光谱法在汞质量浓度0.0～1.0μg/L范围内线性良好,相关系数可以达到0.999 9,方法检出限为0.000 75mg/kg,土壤标准样品测试的相对标准偏差为4.0%～10.7%,实际样品加标回收率分别为93%～104%。采用原子荧光光谱法进行对比测试,原子荧光光谱法的方法检出限为0.002 5 mg/kg,相对标准偏差为4.8%～13.5%,加标回收率为104%～107%。结果表明,对于王水水浴消解土壤的方法不仅适用于原子荧光光谱法测定汞含量,同样可以应用于冷原子吸收光谱法中。所建立的王水消解-冷原子吸收光谱法具有更低的检出限,更优的准确度和精密度,有利于提高土壤样品测试的工作效率,值得推广。     

王水消解-冷原子吸收光谱法测定土壤中汞

为了寻求一种更加适宜测定土壤中汞含量的测试方法,将检出限低、精密度高的冷原子吸收光谱法与便捷、高效的王水水浴消解土壤处理方式相结合,建立了王水消解-冷原子吸收光谱法测定土壤中汞。通过测定方法的线性相关性、方法检出限、准确度、精密度、加标回收率,并与原子荧光光谱法进行对比实验来评价该方法的有效性。王水消解-冷原子吸收光谱法在汞质量浓度0.0~1.0μg/L范围内线性良好,相关系数可以达到0.9999,方法检出限为0.00075 mg/kg,土壤标准样品测试的相对标准偏差为4.0%~10.7%,实际样品加标回收率分别为93%~104%。采用原子荧光光谱法进行对比测试,原子荧光光谱法的方法检出限为0.0025 mg/kg,相对标准偏差为4.8%~13.5%,加标回收率为104%~107%。结果表明,对于王水水浴消解土壤的方法不仅适用于原子荧光光谱法测定汞含量,同样可以应用于冷原子吸收光谱法中。所建立的王水消解-冷原子吸收光谱法具有更低的检出限,更优的准确度和精密度,有利于提高土壤样品测试的工作效率,值得推广。     

Determination of sub-nanogram amounts of mercury by cold-vapour atomic fluorescence spectrometry with an improved gas-sheathed atom cell

An improved gas sheathed cell for the cold-vapour determination of mercury by atomic fluorescence spectrometry is described. Mercury ions in aqueous solution are reduced by tin(II) chloride, and the mercury flushed from solution by argon is discharged from a tube situated adjacent to the spectrometer entrance slit and a mercury electrodeless discharge lamp. A second stream of argon is directed up small capillaries arranged around this outlet tube to provide a laminar sheath of argon around the atom cell. At optimised flow rates, the signal is about 10 times greater than when no laminar sheath is provided. Precision is also improved. The limit of detection (2σ) is 0.01 ng of mercury for a 0.5-ml aliquot of sample (i.e. 20 ng 1^-1). The accuracy of the system is demonstrated by the determination of mercury in NBS Orchard Leaves and in barley seeds. Typically relative standard deviations are in the range 0.6–3%.     

Application of a wool column for flow injection online preconcentration of inorganic mercury(II) and methyl mercury species prior to atomic fluorescence measurement

The use of an unmodified native sheep wool packed minicolumn for the online preconcentration of Hg(II) and methyl mercury species prior to the determination of mercury by atomic fluorescence spectrometry was investigated. Experimental conditions, such as pH, desorbing agents, volume of solution were optimized. 0.5M thioglycolic acid was found to be a successful eluting agent for both mercury species. Breakthrough and total capacities were determined. The method is simple and rapidly applicable for the determination of Hg(II) and methyl mercury in tap water. The accuracy of the method was examined by the analysis of a peach leaves standard reference material. Recoveries of spiked mercury species in tap water were 105.8% for Hg(II) and 98.8% for methyl mercury.     

微波消解-原子荧光光谱法同时测定鱼体中砷和汞

为建立微波消解-原子荧光光谱法同时测定鱼体中砷和汞的测定方法,采用微波消解方法,双道原子荧光光谱法同时测定了鱼体中砷和汞的含量。结果表明,砷与汞的线性范围分别为0.2~2.0μg/L,0.0~50.0μg/L;相关系数分别为r=0.999 8和r=0.999 5;砷回收率为96.5%~101.5%之间,相对标准偏差(n=11)为1.22%,检出限为0.004 2μg/L;汞回收率为98.6%~103.0%,相对标准偏差(n=11)为0.67%,检出限为0.009 6μg/L。用该法测定鱼类中砷和汞,方法灵敏度高、操作简便快速、结果准确可靠。     

Flow injection-chemical vapor generation atomic fluorescence spectrometry hyphenated system for organic mercury determination: A step forward

Monomethylmercury and ethylmercury were determined on line using flow injection-chemical vapor generation atomic fluorescence spectrometry without neither requiring a pre-treatment with chemical oxidants, nor UV/MW additional post column interface, nor organic solvents, nor complexing agents, such as cysteine. Inorganic mercury, monomethylmercury and ethylmercury were detected by atomic fluorescence spectrometry in an Ar/H₂ miniaturized flame after sodium borohydride reduction to Hg⁰, monomethylmercury hydride and ethylmercury hydride, respectively. The effect of mercury complexing agent such as cysteine, ethylendiaminotetracetic acid and HCl with respect to water and Ar/H₂ microflame was investigated.The behavior of inorganic mercury, monomethylmercury and ethylmercury and their cysteine-complexes was also studied by continuous flow-chemical vapor generation atomic fluorescence spectrometry in order to characterize the reduction reaction with tetrahydroborate. When complexed with cysteine, inorganic mercury, monomethylmercury and ethylmercury cannot be separately quantified varying tetrahydroborate concentration due to a lack of selectivity, and their speciation requires a pre-separation stage (e.g. a chromatographic separation). If not complexed with cysteine, monomethylmercury and ethylmercury cannot be separated, as well, but their sum can be quantified separately with respect to inorganic mercury choosing a suitable concentration of tetrahydroborate (e.g. 10^? 5 mol L^? 1), thus allowing the organic/inorganic mercury speciation.The detection limits of the flow injection-chemical vapor generation atomic fluorescence spectrometry method were about 45 nmol L^? 1 (as mercury) for all the species considered, a relative standard deviation ranging between 1.8 and 2.9% and a linear dynamic range between 0.1 and 5 μmol L^? 1 were obtained. Recoveries of monomethylmercury and ethylmercury with respect to inorganic mercury were never less than 91%. Flow injection-chemical vapor generation atomic fluorescence spectrometry method was validated by analyzing the TORT-1 certificate reference material, which contains only monomethylmercury, and obtaining 83 ± 5% of monomethylmercury recovered, respectively. This method was also applied to the determination of monomethylmercury in saliva samples.