Two kinds of novel sulfhydryl functionalized covalent organic frameworks were fabricated as adsorbents for the removal of ultra-trace concentrations of Hg^(2+)from water.The two kinds of sulfhydryl functionalized cova...Two kinds of novel sulfhydryl functionalized covalent organic frameworks were fabricated as adsorbents for the removal of ultra-trace concentrations of Hg^(2+)from water.The two kinds of sulfhydryl functionalized covalent organic frameworks were obtained via a thiol-ene click reaction between the thiol groups of trithiocyanuric acid(TTC)or bismuththiol(BMT)and vinyl groups on the surface of covalent organic frameworks.The material structure was characterized by XRD,SEM,EDS,FT-IR,BET,and TG analysis.Due to their rich sulfur content,both adsorbents(COF-SH-1 and COF-SH-2)exhibited a high level of selective Hg^(2+)removal from aqueous solution with maximum adsorption capacities of 763.4 mg g^(-1) and526.3 mg g^(-1),respectively.Furthermore,in the presence of ultra-low concentrations of Hg^(2+)both materials exhibited excellent performance,achieving rapid Hg^(2+)removal at concentrations from 10μg L^(-1) to less than 0.02 ng L^(-1).Analysis of the adsorption mechanism indicates that the sulfur containing chelating groups exhibit a strong binding capacity for Hg^(2+).Results show that the structure determines the performance,with the amount of adsorption sites being related to the adsorption capacity.Therefore,as sulfhydryl functionalized covalent organic frameworks contain an abundance of adsorption sites,these materials can effectively achieve the removal of ultra-low trace Hg^(2+)concentrations and have promising future application potential for the environmental detection of heavy metals.展开更多
为快速定量唾液对玩具材料中六价铬的迁移量,采用模拟胃液迁移特定元素的迁移模型,在180 r/min的恒温水浴振荡器中,(37±2)℃恒温避光振荡1 h后,(37±2)℃静置1 h,模拟婴幼儿将玩具含入口中的过程。选择硝酸铵作为流动相,以Prin...为快速定量唾液对玩具材料中六价铬的迁移量,采用模拟胃液迁移特定元素的迁移模型,在180 r/min的恒温水浴振荡器中,(37±2)℃恒温避光振荡1 h后,(37±2)℃静置1 h,模拟婴幼儿将玩具含入口中的过程。选择硝酸铵作为流动相,以Prin-Cen ONLY WATER Kit for Cr(Ⅵ)Test Fast column色谱柱作为分析柱,使用紫外可见光检测器进行测定,建立了使用超痕量六价铬分析仪测定模拟唾液迁移玩具材料中六价铬的方法。结果表明,六价铬浓度在0~2μg/L范围内线性关系良好,相关系数能达到1.000,方法检出限为0.006μg/L,方法定量限为0.019μg/L。选取三种实际样品,在低浓度和高浓度下的加标回收率能达到95.0%~105%,在0.5μg/L中等浓度水平下,加标样品的相对标准偏差在3.1%~4.4%。对三种阳性样品进行测定,均能检出较高含量的Cr(Ⅵ)。方法具有良好的准确度和精密度,能应对常见的样品类型,有着较强的适用性。展开更多
In this paper, a novel micro drop solvent extraction technique jonied with low temperature ETV-ICP-AES for ultra trace element analysis is reported. The apparatus of micro drop solvent extraction was designed, and pre...In this paper, a novel micro drop solvent extraction technique jonied with low temperature ETV-ICP-AES for ultra trace element analysis is reported. The apparatus of micro drop solvent extraction was designed, and preliminary investigation was made for the extraction of ultra trace La by a micro drop of 0.05 mol/L PMBP-benzene(2 μL). It was found that 500-fold concentration of ultra-trace La in 1 mL solution was achieved in 0.2 mL of glass chamber by a single micro drop of PMBP-benzene suspended on the tip of a 10 μL of microsyringe. The future development of micro drop solvent extraction technique in atomic spectrometry was briefly discussed.展开更多
基金financially supported by the Fundamental Research Funds for the Central Universities(531118010314)Environmental Protection Science and Technology Project of Hunan Province(20190011)Key R&D Program of Hunan Province(2019SK2281)。
文摘Two kinds of novel sulfhydryl functionalized covalent organic frameworks were fabricated as adsorbents for the removal of ultra-trace concentrations of Hg^(2+)from water.The two kinds of sulfhydryl functionalized covalent organic frameworks were obtained via a thiol-ene click reaction between the thiol groups of trithiocyanuric acid(TTC)or bismuththiol(BMT)and vinyl groups on the surface of covalent organic frameworks.The material structure was characterized by XRD,SEM,EDS,FT-IR,BET,and TG analysis.Due to their rich sulfur content,both adsorbents(COF-SH-1 and COF-SH-2)exhibited a high level of selective Hg^(2+)removal from aqueous solution with maximum adsorption capacities of 763.4 mg g^(-1) and526.3 mg g^(-1),respectively.Furthermore,in the presence of ultra-low concentrations of Hg^(2+)both materials exhibited excellent performance,achieving rapid Hg^(2+)removal at concentrations from 10μg L^(-1) to less than 0.02 ng L^(-1).Analysis of the adsorption mechanism indicates that the sulfur containing chelating groups exhibit a strong binding capacity for Hg^(2+).Results show that the structure determines the performance,with the amount of adsorption sites being related to the adsorption capacity.Therefore,as sulfhydryl functionalized covalent organic frameworks contain an abundance of adsorption sites,these materials can effectively achieve the removal of ultra-low trace Hg^(2+)concentrations and have promising future application potential for the environmental detection of heavy metals.
文摘为快速定量唾液对玩具材料中六价铬的迁移量,采用模拟胃液迁移特定元素的迁移模型,在180 r/min的恒温水浴振荡器中,(37±2)℃恒温避光振荡1 h后,(37±2)℃静置1 h,模拟婴幼儿将玩具含入口中的过程。选择硝酸铵作为流动相,以Prin-Cen ONLY WATER Kit for Cr(Ⅵ)Test Fast column色谱柱作为分析柱,使用紫外可见光检测器进行测定,建立了使用超痕量六价铬分析仪测定模拟唾液迁移玩具材料中六价铬的方法。结果表明,六价铬浓度在0~2μg/L范围内线性关系良好,相关系数能达到1.000,方法检出限为0.006μg/L,方法定量限为0.019μg/L。选取三种实际样品,在低浓度和高浓度下的加标回收率能达到95.0%~105%,在0.5μg/L中等浓度水平下,加标样品的相对标准偏差在3.1%~4.4%。对三种阳性样品进行测定,均能检出较高含量的Cr(Ⅵ)。方法具有良好的准确度和精密度,能应对常见的样品类型,有着较强的适用性。
文摘In this paper, a novel micro drop solvent extraction technique jonied with low temperature ETV-ICP-AES for ultra trace element analysis is reported. The apparatus of micro drop solvent extraction was designed, and preliminary investigation was made for the extraction of ultra trace La by a micro drop of 0.05 mol/L PMBP-benzene(2 μL). It was found that 500-fold concentration of ultra-trace La in 1 mL solution was achieved in 0.2 mL of glass chamber by a single micro drop of PMBP-benzene suspended on the tip of a 10 μL of microsyringe. The future development of micro drop solvent extraction technique in atomic spectrometry was briefly discussed.
