A novel adsorbent was developed by coating yttrium hydroxide precipitate layer on cellulose fibre. This material takes up ca. 98% of 5 μg·L 1 As（Ⅲ） and As（V） at low pH （pH〈7）, while a favorable selectivi...A novel adsorbent was developed by coating yttrium hydroxide precipitate layer on cellulose fibre. This material takes up ca. 98% of 5 μg·L 1 As（Ⅲ） and As（V） at low pH （pH〈7）, while a favorable selectivity for As（V） was achieved within pH 11--12. In practice, a mini-column packed with Y（OH）3 precipitate layer coated cellulose fibre particles was incorporated into a sequential injection system for selective uptake of arsenate at pH 11.5. The retained arsenate was afterwards recovered with 50μL of 0.8 mol.L l NaOH solution as eluent, followed by hydride generation in a reaction medium of 2.0 mol·L-1 HCl and 1.0% NaBH4 solution （W/V, in 0.5% NaOH） after pre-reduction of arsenate to arsenite by KI-ascorbic acid （5%, W/V）, with detection by atomic fluorescence spec- trometry. Total inorganic arsenic was quantitatively taken up at pH 6.0 by following the same procedure and arsenic speciation was performed by difference. With a sample volume of 1.0 mL, an enrichment factor of 16.4 was derived with a detection limit of 17 ng.L-1 within a linear range of 0.05--2.0μg.L ]. A relative standard deviation （RSD） of 2.6% （0.5 μg·L-1, n= 11） was achieved. The procedure was validated by analyzing arsenic in a certified refer- ence material GBW 09101 （human hair）, and speciation process requires no organic solvents, thus Y（OH）3 coated of inorganic arsenic in natural water samples. The entire cellulose fibre provides a green adsorbent.展开更多
目的分析测定云南滇东8个州市鱼类中砷的形态以及含量。方法鱼类样品经石墨湿法消解,采用电感耦合等离子体质谱法测定总砷含量;相同的样品经1%硝酸热提取无机砷,采用液相色谱-原子荧光光谱法测定各形态砷含量。结果总砷及无机砷在一定...目的分析测定云南滇东8个州市鱼类中砷的形态以及含量。方法鱼类样品经石墨湿法消解,采用电感耦合等离子体质谱法测定总砷含量;相同的样品经1%硝酸热提取无机砷,采用液相色谱-原子荧光光谱法测定各形态砷含量。结果总砷及无机砷在一定浓度范围内分别有良好的线性关系,相关系数均大于0.999,总砷的加标回收率为93.57%~95.0%,其他形态砷的加标回收率为89.03%~92.04%,测定总砷的质控样均在参考值范围内。132件样品中总砷含量为0-2.31 m g/kg;无机砷中三价砷的含量为0~0.279mg/kg,其中昆明、红河及玉溪的样品有部分超标,超标率分别的为26.09%、22.22%、11.11%。结论有131件鱼样品检出总砷和无机砷,无机砷含量大部分达到国家标准要求,只有少部分超出标准限值。应加强对水产品中砷的监测,以确保鱼类食品的安全。展开更多
文摘A novel adsorbent was developed by coating yttrium hydroxide precipitate layer on cellulose fibre. This material takes up ca. 98% of 5 μg·L 1 As（Ⅲ） and As（V） at low pH （pH〈7）, while a favorable selectivity for As（V） was achieved within pH 11--12. In practice, a mini-column packed with Y（OH）3 precipitate layer coated cellulose fibre particles was incorporated into a sequential injection system for selective uptake of arsenate at pH 11.5. The retained arsenate was afterwards recovered with 50μL of 0.8 mol.L l NaOH solution as eluent, followed by hydride generation in a reaction medium of 2.0 mol·L-1 HCl and 1.0% NaBH4 solution （W/V, in 0.5% NaOH） after pre-reduction of arsenate to arsenite by KI-ascorbic acid （5%, W/V）, with detection by atomic fluorescence spec- trometry. Total inorganic arsenic was quantitatively taken up at pH 6.0 by following the same procedure and arsenic speciation was performed by difference. With a sample volume of 1.0 mL, an enrichment factor of 16.4 was derived with a detection limit of 17 ng.L-1 within a linear range of 0.05--2.0μg.L ]. A relative standard deviation （RSD） of 2.6% （0.5 μg·L-1, n= 11） was achieved. The procedure was validated by analyzing arsenic in a certified refer- ence material GBW 09101 （human hair）, and speciation process requires no organic solvents, thus Y（OH）3 coated of inorganic arsenic in natural water samples. The entire cellulose fibre provides a green adsorbent.
文摘目的分析测定云南滇东8个州市鱼类中砷的形态以及含量。方法鱼类样品经石墨湿法消解,采用电感耦合等离子体质谱法测定总砷含量;相同的样品经1%硝酸热提取无机砷,采用液相色谱-原子荧光光谱法测定各形态砷含量。结果总砷及无机砷在一定浓度范围内分别有良好的线性关系,相关系数均大于0.999,总砷的加标回收率为93.57%~95.0%,其他形态砷的加标回收率为89.03%~92.04%,测定总砷的质控样均在参考值范围内。132件样品中总砷含量为0-2.31 m g/kg;无机砷中三价砷的含量为0~0.279mg/kg,其中昆明、红河及玉溪的样品有部分超标,超标率分别的为26.09%、22.22%、11.11%。结论有131件鱼样品检出总砷和无机砷,无机砷含量大部分达到国家标准要求,只有少部分超出标准限值。应加强对水产品中砷的监测,以确保鱼类食品的安全。
