A micro-flow injection sorbent extraction preconcentration system was combined with a graphite furnace atomic absorption spectrometry that formed an integrated system for the determination of trace amounts of elements...A micro-flow injection sorbent extraction preconcentration system was combined with a graphite furnace atomic absorption spectrometry that formed an integrated system for the determination of trace amounts of elements. The analytical performances of the prospsed method for determining Cd, Cu and Mn were studied. The analytes were preconcentrated with a thiol resin(Type 190, produced by Nankai University, China) whose active group is -SH. The elements to be determined were preconcentrated onto the column for 60 s and then rinsed with deionized water and eluted with 30 μL of 1 mol/L HCl. The graphite furnace atomic absorption spectrometry(GFAAS) determination of the concentrated analyte was carried out in parallel with the next preconcentration cycle. Enrichment factors 41, 22 and 20 and detection limits(3 σ , n =10) 0.36, 3.8 and 7.0 ng/L for Cd, Cu and Mn, respectively, along with a sampling frequency of 20 h -1 , were obtained with a 60 s loading time at a sample flow rate of 3.5 mL/min. The analytical results for a number of water samples show that the flow-injection semi-online column preconcentration can not only eliminate the effect of some concomitant elements, such as Li, Na, K, Ca and Mg, on the determination of the analyte, but also enhance the sensitivity.展开更多
On-line ion-exchange separation and preconcentration were combined with flow-injection hydride generation atomic absorption spectrometry (HGAAS) to determine ultra-trace amounts of antimony in water samples. Antimony(...On-line ion-exchange separation and preconcentration were combined with flow-injection hydride generation atomic absorption spectrometry (HGAAS) to determine ultra-trace amounts of antimony in water samples. Antimony(Ⅲ) was preconcentrated on a micro-column packed with CPG-8Q chelating ion-exchanger using time-based sample loading and eluted by 4 mol l^(-1) HCl directly into the hydride generation AAS system. A detection limit (3σ) of 0.0015μg l^(-1) Sb(Ⅲ) was obtained on the basis of a 20 fold enrichment and with a sampling frequency of 60h^(-1). The precision was 1.0% r.s.d.(n=11) at the 0.5μg l^(-1) Sb(Ⅲ) level. Recoveries for the analysis of antimony in tap water, snow water and sea water samples were in the range 97-102%.展开更多
以氨丙基硅三烷作为改性剂,对介孔二氧化硅表面进行修饰,制备了氨基化介孔二氧化硅吸附材料,采用透射电镜和傅立叶红外光谱仪对其进行表征,并用于水样中痕量镉的富集,建立了氨基化介孔二氧化硅分离预富集/火焰原子吸收光谱法测定痕量镉...以氨丙基硅三烷作为改性剂,对介孔二氧化硅表面进行修饰,制备了氨基化介孔二氧化硅吸附材料,采用透射电镜和傅立叶红外光谱仪对其进行表征,并用于水样中痕量镉的富集,建立了氨基化介孔二氧化硅分离预富集/火焰原子吸收光谱法测定痕量镉的方法。考察了溶液pH值、样品流速、洗脱剂类型、干扰离子和吸附容量等对痕量镉分离富集的影响,以及该吸附材料对痕量镉（Ⅱ）的吸附性能。结果表明,溶液pH 7.0,样品流速8 m L/min时镉离子能被制备材料高效吸附,吸附的镉（Ⅱ）用5.0 m L 2 mol/L HNO_3完全洗脱,火焰原子吸收法测定。在最佳实验条件下,方法的线性范围为0.6～20 ng/m L,定量下限为0.5 ng/m L,富集倍数为50倍,对10 ng/m L Cd2＋测定的相对标准偏差（n=11）为0.92%,加标回收率为98.8%～104.5%。该方法的抗干扰能力较好,富集柱可循环使用12次以上,可用于环境水样中镉（Ⅱ）的测定。展开更多
该文制备了一种新型吸附材料三乙烯四胺修饰β-环糊精交联树脂（TETA-β-CDP）,并对其进行红外光谱表征,优化了该吸附材料对痕量铅、镉的吸附和解析条件,建立了动态条件下同时分离富集/原子吸收光谱测定大米中铅和镉的新方法。在p H 5.5...该文制备了一种新型吸附材料三乙烯四胺修饰β-环糊精交联树脂（TETA-β-CDP）,并对其进行红外光谱表征,优化了该吸附材料对痕量铅、镉的吸附和解析条件,建立了动态条件下同时分离富集/原子吸收光谱测定大米中铅和镉的新方法。在p H 5.5时,样品溶液以1.0 m L/min流速过柱,试液中的Pb2＋和Cd2＋可被该树脂定量富集,其动态饱和吸附容量分别为22.8,31.3 mg/g,吸附在TETA-β-CDP上的Pb2＋和Cd2＋可用0.1 mol/L HCl以0.8 m L/min流速完全洗脱。该方法对铅、镉的检出限（3σ,n=11）分别为0.038 mg/L和0.016 mg/L;线性范围分别为0.2~20 mg/L和0.05~2.5 mg/L;相对标准偏差（RSD）分别为2.8%和1.7%;加标回收率分别为97.5%~101.0%和95.0%~102.5%。该方法用于大米样品中痕量铅、镉的测定,结果满意。展开更多
文摘A micro-flow injection sorbent extraction preconcentration system was combined with a graphite furnace atomic absorption spectrometry that formed an integrated system for the determination of trace amounts of elements. The analytical performances of the prospsed method for determining Cd, Cu and Mn were studied. The analytes were preconcentrated with a thiol resin(Type 190, produced by Nankai University, China) whose active group is -SH. The elements to be determined were preconcentrated onto the column for 60 s and then rinsed with deionized water and eluted with 30 μL of 1 mol/L HCl. The graphite furnace atomic absorption spectrometry(GFAAS) determination of the concentrated analyte was carried out in parallel with the next preconcentration cycle. Enrichment factors 41, 22 and 20 and detection limits(3 σ , n =10) 0.36, 3.8 and 7.0 ng/L for Cd, Cu and Mn, respectively, along with a sampling frequency of 20 h -1 , were obtained with a 60 s loading time at a sample flow rate of 3.5 mL/min. The analytical results for a number of water samples show that the flow-injection semi-online column preconcentration can not only eliminate the effect of some concomitant elements, such as Li, Na, K, Ca and Mg, on the determination of the analyte, but also enhance the sensitivity.
文摘On-line ion-exchange separation and preconcentration were combined with flow-injection hydride generation atomic absorption spectrometry (HGAAS) to determine ultra-trace amounts of antimony in water samples. Antimony(Ⅲ) was preconcentrated on a micro-column packed with CPG-8Q chelating ion-exchanger using time-based sample loading and eluted by 4 mol l^(-1) HCl directly into the hydride generation AAS system. A detection limit (3σ) of 0.0015μg l^(-1) Sb(Ⅲ) was obtained on the basis of a 20 fold enrichment and with a sampling frequency of 60h^(-1). The precision was 1.0% r.s.d.(n=11) at the 0.5μg l^(-1) Sb(Ⅲ) level. Recoveries for the analysis of antimony in tap water, snow water and sea water samples were in the range 97-102%.
文摘以氨丙基硅三烷作为改性剂,对介孔二氧化硅表面进行修饰,制备了氨基化介孔二氧化硅吸附材料,采用透射电镜和傅立叶红外光谱仪对其进行表征,并用于水样中痕量镉的富集,建立了氨基化介孔二氧化硅分离预富集/火焰原子吸收光谱法测定痕量镉的方法。考察了溶液pH值、样品流速、洗脱剂类型、干扰离子和吸附容量等对痕量镉分离富集的影响,以及该吸附材料对痕量镉（Ⅱ）的吸附性能。结果表明,溶液pH 7.0,样品流速8 m L/min时镉离子能被制备材料高效吸附,吸附的镉（Ⅱ）用5.0 m L 2 mol/L HNO_3完全洗脱,火焰原子吸收法测定。在最佳实验条件下,方法的线性范围为0.6～20 ng/m L,定量下限为0.5 ng/m L,富集倍数为50倍,对10 ng/m L Cd2＋测定的相对标准偏差（n=11）为0.92%,加标回收率为98.8%～104.5%。该方法的抗干扰能力较好,富集柱可循环使用12次以上,可用于环境水样中镉（Ⅱ）的测定。
文摘该文制备了一种新型吸附材料三乙烯四胺修饰β-环糊精交联树脂（TETA-β-CDP）,并对其进行红外光谱表征,优化了该吸附材料对痕量铅、镉的吸附和解析条件,建立了动态条件下同时分离富集/原子吸收光谱测定大米中铅和镉的新方法。在p H 5.5时,样品溶液以1.0 m L/min流速过柱,试液中的Pb2＋和Cd2＋可被该树脂定量富集,其动态饱和吸附容量分别为22.8,31.3 mg/g,吸附在TETA-β-CDP上的Pb2＋和Cd2＋可用0.1 mol/L HCl以0.8 m L/min流速完全洗脱。该方法对铅、镉的检出限（3σ,n=11）分别为0.038 mg/L和0.016 mg/L;线性范围分别为0.2~20 mg/L和0.05~2.5 mg/L;相对标准偏差（RSD）分别为2.8%和1.7%;加标回收率分别为97.5%~101.0%和95.0%~102.5%。该方法用于大米样品中痕量铅、镉的测定,结果满意。
