流动注射在线萃取色谱预浓集火焰原子吸收法测定钯

以三异辛胺萃淋树脂为微型柱固定相，采用流动注射在线预浓集与火焰原子吸收法联用技术，对微量钯的测定进行了研究。在0.5mol/L的HCl介质中以7.8mL/min的速率采样90s再用0.1mol/L硫脲－0.5mol/L HCl洗脱；在27h^-1的采样频率下，浓集系数为50倍，浓集效率为22.5min，消耗指数0.23mL。线性范围为0－1000μg/L，检出限为0.34μg/L。钯含量水平50μg/L时，连续11次测定的相对标准偏差为2.6%，并对加氢催化剂中的钯进行了加标回收率实验，回收率为99.3%-101.2%。     

流动注射在线预浓集－火焰原子吸收光谱法测定葡萄酒中微量铅

流动注射在线预浓集－火焰原子吸收光谱法测定葡萄酒中微量铅孙晓娟（江苏石油化工学院应用化学系，常州，２１３０１６）Ｂ．ＷｅｌｚＭ．Ｓｐｅｒｌｉｎｇ（Ｐ－Ｅ有限公司，Ｄ－８８６６２　于伯林根，德国）关键词铅，葡萄酒，微波消解，流动注射在线预浓集，火焰原子...     

流动注射在线共沉淀预富集火焰原子吸收法测定痕量铜

研究了以Ｎｉ＾２＋－ＤＤＴＣ为共沉淀载体，流动注射在线共沉淀预富集－火焰原子吸收光谱法测定痕量铜的体系，在０．３ｍｏｌ．Ｌ＾－１的硝酸介质中，铜离子在编织反应器中与Ｎｉ＾２＋－ＤＤＴＣ（产生共沉淀，并被收集在编织器内壁上，用甲基异丁基酮（ＭＩＢＫ）在线洗脱沉积物并引入火争原子化器中测定。当富集时间为４０ｓ时，４０μｇ．Ｌ＾－１的铜１０次测定的相对标准偏差为３．０％，灵敏度提高６０倍，检出限（３σ）     

在线流动注射螯合树脂预富集石英缝管增敏火焰原子吸收法测定水中痕量铅

应用高效的在线流动注射螯合树脂预富集石英缝管增敏火焰原子吸收系统直接测定水呈痕量铅。实验用内装２００ｍｇＡｍｂｅｒｌｉｔｅＸＡＤ－４键合的５－磺酸－８羟基喹啉螯合树脂的锥形柱,在ＰＨ９条件下样品流速为８．０ｍＬ／ｍｉｎ,９０ｓ采样,用０．５ｍｏｌ／Ｌ Ｈｃｌ洗脱,在分析速度为３０样／ｈ,获得３６倍的富集,经石英缝管增敏,灵敏度提高达１１５倍,线性范围为０－２００μｇ／Ｌ,检出限为１μｇ／Ｌ。铅含量水平５０μｇ／Ｌ的水样连续测定１１次的相对标准偏差２．５％,可直接测定水体中μｇ／Ｌ级的铅。     

微柱流动注射在线预浓集与电热原子吸收光谱法的全自动联用

研究了一种流动注射在线预浓集、分离与电热原子吸收光谱全自动联用的最新技术，在最优化条件下，采用９μＬ微柱预浓集，８０μＬ甲醇洗脱剂可将吸附于微柱上的待测物定量洗脱并全部自动导入石墨炉原子化器。富集倍数高达６４，进行了河和海水标准参考物质中痕量铅的测定，无基体干扰，不必使用基体改进剂，结果满意，检出限４．５ｎｇ／Ｌ，回收率９７－１０４％，相对标准偏差为２．９％。     

在线预浓集流动注射测定苯酚

基于ＶＳ－Ⅱ阴离子交换纤维对苯酚的吸附，建立了以ＶＳ－Ⅱ阴离子交换纤维柱在线预浓集、流动注射４－氨基安替比林分光光度测定苯酚的方法，方法的线性范围为０．０１－１．４０ｍｇ／Ｌ；进样频率可达９０次／ｈ，应用于环境污染水中苯酚的测定，结果满意。     

电渗泵—流动注射在线稀释法在火焰原子吸收光谱分析高浓度样品中？…

采用电渗泵流动注射－火焰原子吸收法（ＦＩ－ＦＡＡＳ）,研究了高浓度镁样品的在线稀释和分析。电渗泵在低流量时有很好的稳定性。利用控制采样时间的办法,可以准确采集微量样品,在线稀释。同时使用Ｔ型客对雾化量进行补偿,在线稀释倍数可达１０００以上,相对标准偏差〈１．５％（ｎ＝６）。通过改变采样电压（速度）,载流速度和采样时间可以方便地得到不同的稀释倍数,测定速度可达１００个／ｈ样品以上。     

流动注射双硫腙在线共沉淀预浓集石墨炉原子吸收光谱法测定人血中微量镉

本文用流动注射分析技术为石墨炉原子吸收光谱法测定人血中超微量金属元素建立了一个有效的在线共沉淀分离预浓集系统。基于痕量镉与双硫腙(DTZ)在弱酸性水溶液中共沉淀。沉淀收集在一编结反应器及一微型过滤器上,用60μL甲基异丁基酮(MIBK)溶洗沉淀,然后送入石墨炉进行测定。分析速度24样/h,样品消耗为1.4mL,获得的富集倍率为11。检出限(3σ)为0.003μg/L,浓度为0.06μg,/L镉时,测定精度为2.6%(n=7),测定人体血样标准参考物(GBW09132～GBW09134)中镉,结果与标准值一致。     

生物材料对重金属离子的吸附富集作用

介绍了重金属离子的生物吸附富集作用,从生物材料的类型、生物吸附的选择性、化学修饰与生物吸附、生物对重金属离子的浓缩富集作用和生物吸附的机理及模型等方面作了说明。利用生物材料可去除水体中的重金属离子。     

无滤共沉淀富集-等离子体原子发射光谱法测定痕量稀土元素

以编结反应器 (KR)作为反应场所,用NH3～NH4NO3缓冲溶液在线沉淀、富集,电感耦合等离子体原子发射光谱法(ICP-AES)检测稀土元素,系统地研究了稀土元素在线沉淀及溶解的最佳条件.实验结果表明:在80 ℃时,稀土离子与pH 9.0的NH3～NH4NO3缓冲溶液在线混合后经2 m KR富集120 s,用1 mol/L HNO3以1.0 mL/min流速洗脱时富集效果最好,富集倍数可达52～76倍,进样频率为10/h.同时考察了共存离子的干扰及其消除方法.方法的稀土元素的检出限为0.07～1.23 μg/L,精密度RSD在1.7%～4.3%之间(n=6),线性范围2～10 μg/L.应用于标准样品中痕量稀土元素的测定,其测定值与标准值吻合.     

Further study on a flow injection on-line multiplexed sorption preconcentration coupled with flame atomic absorption spectrometry for trace element determination

A further study on a newly developed flow injection (FI) on-line multiplexed sorption preconcentration (MSP) using a knotted reactor coupled with flame atomic absorption spectrometry (FAAS) was carried out to demonstrate its applicability and limitation for trace element determination. For this purpose, Cr(VI), Cu(II), Ni(II) and Co(II) were selected as the analytes, and detailed comparison was made between the MSP-FAAS and conventional FI on-line sorption preconcentration FAAS in respect to retention efficiency and linear ranges of absorbance versus sample loading flow rate and total preconcentration time. Introduction of an air-flow for removal of the residual solution in the KR after each sub-injection in the MSP procedure played a decisive role in the improvement of retention efficiency. The linearity of absorbance versus sample loading flow rate or total preconcentration time was extended to a more degree for the metal ions with less stability of their PDC (pyrrolidine dithiocarbamate) complexes than those with more stable PDC complexes. It seems that the MSP procedure behaves advantages beyond the inflection points in the diagrams of absorbance versus total preconcentration time and sample loading flow rate obtained by conventional (a single continuous) preconcentration procedure. With a sample loading flow rate of 6.0 ml min⁻¹ and a total preconcentration time of 180 s, the retention efficiencies were increased from 25, 46, 41 and 63% with a single continuous sorption preconcentration to 44, 78, 65 and 75% with a six sub-injection preconcentration procedure for Cr(VI), Co(II), Ni(II), and Cu(II), respectively. The detection limits were 0.40, 0.33, 0.31 and 0.26 μg l⁻¹ for Cr(VI), Co(II), Ni(II), and Cu(II), respectively. The precision (R.S.D.) for eleven replicate determination of 2 μg l⁻¹ Cr(VI), Co(II) and Ni(II), and 1 μg l⁻¹ Cu(II), was 2.1, 4.1, 2.6 and 1.7%, respectively.     

Flow injection on-line preconcentration of low levels of Cr(VI) with detection by ETAAS: Comparison of using an open tubular PTFE knotted reactor and a column reactor packed with PTFE beads

A flow injection (FI) on-line sorption preconcentration procedure utilizing a packed column reactor and combined with electrothermal atomic absorption spectrometry (ETAAS) is proposed for the determination of low levels of Cr(VI) in water samples. Polytetrafluoroethylene (PTFE) beads packed in a mini-column is used as sorbent material. The complex formed between Cr(VI) and ammonium pyrrolidine dithiocarbamate (APDC) is sorbed on the PTFE beads, and is subsequently eluted by an air-monosegmented discrete zone of absolute ethanol (35 μl), the analyte being quantified by ETAAS.The preconcentration procedure using the proposed column significantly enhances the preconcentration efficiency as compared with the preconcentration approach incorporating an open tubular PTFE knotted reactor (KR). Comparing the two procedure for equal surface sorption area, the advantages of using a packed column are observed in terms of limit of detection, enrichment factor and retention efficiency. With a preconcentration time of 60 s, and a sample flow rate of 5.0 ml l⁻¹, the enrichment factor (30.1) and the retention efficiency (24.1%) were doubled, yielding a detection limit (3σ) as low as 8.8 ng l⁻¹. The sample frequency was 16.7 h⁻¹. The concentration efficiency was 8.38 and the precision was 1.05% at 0.5 μg l⁻¹ of Cr(VI). The proposed column has been applied successfully to the analysis of natural water and synthetic seawater. Its performance was verified by the analysis of two certified Cr(VI)-reference materials and by recovery measurements on spiked samples.     

在线预浓缩FIA比浊法测定水中微量硫酸根

在线预浓缩ＦＩＡ比浊法测定水中微量硫酸根李俊锋，郭如江，赵楠，李绍民（长春地质学院应用化学系长春１３００２６）（吉林大学环境科学系）关键词在线预浓缩，ＦＩＡ，硫酸根流动注射比浊法测定微量硫酸根已有报道［１，２］，由于干扰组分的作用使得前处理操作麻烦，...     

Investigation of on-line coupling electrothermal atomic absorption spectrometry with flow injection sorption preconcentration using a knotted reactor for totally automatic determination of lead in water samples

A flow injection on-line sorption preconcentration electrothermal atomic absorption spectrometric system for fully automatic determination of lead in water was investigated. The discrete non-flow-through nature of ETAAS, the limited capacity of the graphite tube and the relatively large volume of the knotted reactor (KR) are obstacles to overcome for the on-line coupling of the KR sorption preconcentration system with ETAAS. A new FI manifold has been developed with the aim of reducing the eluate volume and minimizing dispersion. The lead diethyldithiocarbamate complex was adsorbed on the inner walls of a knotted reactor made of PTFE tubing (100 cm long, 0.5 mm i.d.). After that, an air flow was introduced to remove the residual solution from the KR and the eluate delivery tube, then the adsorbed analyte chelate was quantitatively eluted into a delivery tube with 50 μl of ethanol. An air flow was used to propel the eluent from the eluent loop through the reactor and to introduce all the ethanolic eluate onto the platform of the transversely heated graphite tube atomizer, which was preheated to 80°C. With the use of the new FI manifold, the consumption of eluent was greatly reduced and dispersion was minimized. The adsorption efficiency was 58%, and the enhancement factor was 142 in the concentration range 0.01–0.05 μg l⁻¹ Pb at a sample loading rate of 6.8 ml min⁻¹ with 60 s preconcentration time. For the range 0.1–2.0 μg l⁻¹ of Pb a loading rate of 3.0 ml min⁻¹ and 30 s preconcentration time were chosen, resulting in an adsorption efficiency of 42% and an enhancement factor of 21, respectively. A detection limit (3σ) of 2.2 ng l⁻¹ of lead was obtained using a sample loading rate of 6.8 ml min⁻¹ and 60 s preconcentration. The relative standard deviation of the entire procedure was 4.9% at the 0.01 μg l⁻¹ Pb level with a loading rate of 6.8 ml min⁻¹ and 60 s preconcentration, and 2.9% at the 0.5 μg l⁻¹ Pb level with a 3.0 ml min⁻¹ loading rate and 30 s preconcentration. Efficient washing of the matrix from the reactor was critical, requiring the use of the standard addition method for seawater samples. The analytical results obtained for seawater and river water standard reference materials were in good agreement with the certified values.     

流动注射-氢化物发生-原子荧光光谱法测定天然水中痕量镉

基于编结反应器,提出了流动注射-氢化物发生-原子荧光光谱法测定水中痕量镉含量的方法。样品与氨水-氯化铵缓冲溶液在线混合,产生的沉淀收集到编结反应器内壁,引入空气除去编结反应器内残留的溶液,泵入盐酸(3+97)溶液溶解沉淀,与硼氢化钾合并后用原子荧光光谱仪测定。在优化的试验条件下,当样品消耗15.6mL时,富集倍数为14倍,方法检出限(3S/N)为2.9ng.L-1,相对标准偏差(n=11)为3.4%。方法用于国家标准物质和天然水样中痕量镉的测定,测定值与标准值相符,天然水样的回收率在91.5%～107.5%之间。     

Preconcentration of Cd(II) and Pb(II) Using Humic Substances and Flow Systems Coupled to Flame Atomic Absorption Spectrometry

This paper demonstrates the potential of two natural adsorbents, vermicompost and humic acid, for preconcentration of cadmium(II) and lead(II) using flow systems coupled to flame atomic absorption spectrometry (FAAS). The procedure involves the adsorption of Cd(II) or Pb(II) on these materials (using columns containing 25mg) and subsequent elution for determination by FAAS. Cadmium(II) was preconcentrated for 4min (flow rate of 4.0mLmin^–1) and eluted with 220µL of 3.0molL^–1 HNO₃. Under these conditions, preconcentration factors of 46 and 27 were obtained for vermicompost and humic acid, respectively. Except when using 1.0molL^–1 nitric acid (for humic acid), all conditions for lead(II) preconcentration were identical to those for cadmium(II), and preconcentration factors of 62 and 83 were obtained when vermicompost and humic acid, respectively, were used. The systems were stable with only slight variations in the slopes of the analytical curves (ca. 5% after 8h working period). The long-term stability shows that a minimum of 120 and 100 cycles, respectively, can be run using the same masses of vermicompost or humic acid. The detection limits for Cd(II) were 0.4 and 0.8µgL^–1 for vermicompost and humic acid respectively, while the detection limits for Pb(II) were 8.8 and 12.1µgL^–1, also for vermicompost and humic acid. The accuracy of the methods was checked by using spiked and real (certified and reference) samples. Due to the concomitant sorption of other metals leading to variable slopes for lead and cadmium determination, it was necessary to adopt the standard addition method for calibration purposes.     

二苯硫脲纤维素分离富集—火焰原子吸收法测定地质样品中痕量银

在王水介质中，采用二苯硫脲螯合纤维素吸附以除去地质样品中大部分干扰离子，被吸附的银用硫脲溶液解吸并用火焰原子吸收光谱测定。研究了分离和测定的条件，２０余种共存离子对银的测定无显著影响。该法已成功地应用于地质样品中痕量银的测定。     

FIA活性碳纤维在线富集水样中痕量元素及ICP－AES检测

本文研究了新型吸附材料－活性碳纤维的在线分离富集特性，用ＦＩ活性碳纤维填充的锥形柱，实现痕量金属元素Ｚｎ、Ｐｈ、Ｎｉ、Ｃｏ、Ｃｄ、Ｍｎ的在线富集。经ＨＮＯ３洗脱后．由ＩＣＰ－ＡＥＳ检测，测定速率达３０样／ｈ，检出限（ｎｇ／ｍＬ）分别为：０．４（Ｚｎ）、４．０（Ｐｈ）．０．９（Ｎｉ）、０．４（Ｃｏ）、０．４（Ｃｄ）、０．７（Ｍｎ），富集柱可使用多次。