该工作以富含大量胸腺嘧啶（Thymine，T）核酸单链为识别分子，SYBR Green I （SG）为荧光基团，建立了一种简单、灵敏的荧光增强法检测Hg2＋。由于T-Hg2＋-T键的形成，富T单链自我折叠或者两两配对形成双链DNA结构，当溶液中的SG嵌入DN...该工作以富含大量胸腺嘧啶（Thymine，T）核酸单链为识别分子，SYBR Green I （SG）为荧光基团，建立了一种简单、灵敏的荧光增强法检测Hg2＋。由于T-Hg2＋-T键的形成，富T单链自我折叠或者两两配对形成双链DNA结构，当溶液中的SG嵌入DNA双链中时，SG荧光强度显著增强。实验结果表明，SG荧光强度随着Hg2＋浓度的增加而增加。在最优实验条件下，SG的荧光强度与Hg2＋的浓度在4．000×10-7~2．000×10-6 mol/L范围内呈线性关系，检出限为3．900×10-8 mol/L。该方法在含5．0％湘江水实际样品中获得的回收率为98．72％~104．5％，因此该传感器可用于实际湘江水样品中Hg2＋的测量。展开更多
Photoreduction characteristics of divalent inorganic mercury (Hg2+) in the presence of specific algae species are still not well known.Laboratory experiments were conducted in the present study to identify the effects...Photoreduction characteristics of divalent inorganic mercury (Hg2+) in the presence of specific algae species are still not well known.Laboratory experiments were conducted in the present study to identify the effects of different concentrations of living/dead algae species,including Aphanizomenon flosaquae (AF) and Microcystis aeruginosa (MA),on the photoreduction rate of Hg2+ under various light conditions.The experimental results showed that percentage reduction of Hg2+ was significantly influenced by radiation wavelengths,and dramatically decreased with the presence of algae.The highest percentage reduction of Hg2+ was induced by UV-A,followed by UV-B,visible light and dark for both living and dead AF,and the order was dark > UV-A > UV-B > visible light for both living and dead MA.There were two aspects,i.e.,energy and attenuation rate of light radiation and excrementitious generated from algae metabolisms,were involved in the processes of Hg2+ photoreduction with the presence of algae under different light conditions.The percentage reduction of Hg2+ decreased from 15% to 11% when living and dead AF concentrations increased by 10 times (from 106 to 105 cells/mL),and decreased from11% to ~9% in the case of living and dead MA increased.Algae can adsorb Hg2+ and decrease the concentration of free Hg2+,thus inhibiting Hg2+ photoreduction,especially under the conditions with high concentrations of algae.No significant differences were found in percentage reduction of Hg2+ between living and dead treatments of algae species.The results are of great importance for understanding the role of algae in Hg2+ photoreduction.展开更多
The stronger coordination ability of mercury ions with organic ligands than the metal ions in metal organic framework(MOFs) provides an accessible way to separate mercury ions from solution using specific MOFs. In thi...The stronger coordination ability of mercury ions with organic ligands than the metal ions in metal organic framework(MOFs) provides an accessible way to separate mercury ions from solution using specific MOFs. In this study, a Co-based MOF(ZIF-67, Co(mIM)) was synthesized. It did not introduce specific functional groups, such as-SH and-NH, into its structure through complicated steps. It separate Hgfrom wastewater with a new strategy, which utilized the stronger coordination ability of Hgwith the nitrogen atom on the imidazole ring of the organic ligand than the Coions. Hgreplaced Conodes from ZIF-67 and formed a more stable precipitate with m IM. The experimental results showed that this new strategy was efficient. ZIF-67 exhibited Hgadsorption capacity of 1740 mg/g, much higher than the known MOFs sorbents. m IMs is the reaction center and ZIF-67 can improve its utilization. The sample color faded from purple to white due to the loss of cobalt ion. It is a great feature of ZIF-67 that allows users to judge whether the sorbent is deactivated intuitively. ZIF-67 can be sustainable recycled by adding organic ligands to the solution after treatment due to its simple synthesis method at room temperature. It’s a high-efficient and sustainable sorbent for Hgseparation from wastewater.展开更多
Based on the two-component relativistic effective core potential and matched basis sets cc-pwcvnz-pp （n=Q, 5）, combining the completed basis-set extrapolation of electronic correlation energy and the fourth-order po...Based on the two-component relativistic effective core potential and matched basis sets cc-pwcvnz-pp （n=Q, 5）, combining the completed basis-set extrapolation of electronic correlation energy and the fourth-order polynomial fitting technique, the bond length and spectroscopic constants of Hg2 are studied by the coupled cluster theory with spin-orbit coupling. Spin-orbit coupling is included in the post Hartree-Fock procedure, i.e., in the coupled- cluster iteration, to obtain more reliable theoretical results. The results show that our theoretical values agree with the experimental values very well and will be helpful to understand the spectral character of Hg2.展开更多
Mesoporous silica materials with uniform channels containing functionalized organic monolayers have been synthesized by grafting a thiol functional group, （3-Mercaptopropyl） trimethoxysilane （MPTMS）. A new approac...Mesoporous silica materials with uniform channels containing functionalized organic monolayers have been synthesized by grafting a thiol functional group, （3-Mercaptopropyl） trimethoxysilane （MPTMS）. A new approach to heavy metal ion adsorbents based on the covalent grafting of MPTMS groups to the framework pore walls of mesoporous silica molecular sieves has been developed and investigated with regard to hydroxyl group densities, channel dimensions, morphologies and reaction conditions. Results show that the ordered mesostructures of functionalized samples were retained after modification and the thiol functional group was immobilized mainly inside the mesopore channel. The relative surface coverage of the monolayer can be systematically varied up to 95%. The functionalized hybrid materials show exceptional selectivity and capacity for removing mercury from aqueous waste stream with distribution coefficients up to 435,000. The regenerated material show high mercury ion uptake capacity of 2.87 mmol/g （86.5%）.展开更多
文摘该工作以富含大量胸腺嘧啶（Thymine，T）核酸单链为识别分子，SYBR Green I （SG）为荧光基团，建立了一种简单、灵敏的荧光增强法检测Hg2＋。由于T-Hg2＋-T键的形成，富T单链自我折叠或者两两配对形成双链DNA结构，当溶液中的SG嵌入DNA双链中时，SG荧光强度显著增强。实验结果表明，SG荧光强度随着Hg2＋浓度的增加而增加。在最优实验条件下，SG的荧光强度与Hg2＋的浓度在4．000×10-7~2．000×10-6 mol/L范围内呈线性关系，检出限为3．900×10-8 mol/L。该方法在含5．0％湘江水实际样品中获得的回收率为98．72％~104．5％，因此该传感器可用于实际湘江水样品中Hg2＋的测量。
基金supported by the Science and Technology Department of Guizhou Province(No.Qiankehe LH zi [2017]7334hao)the China Postdoctoral Science Foundation(No.2017M613005)+2 种基金Foundation of Guizhou Educational Committee(No.Qian jiao he KY[2016]135)the National Natural Science Foundation of China(No.41563012)the Doctoral Scientific Research Foundation of Guizhou Normal University for 2014
文摘Photoreduction characteristics of divalent inorganic mercury (Hg2+) in the presence of specific algae species are still not well known.Laboratory experiments were conducted in the present study to identify the effects of different concentrations of living/dead algae species,including Aphanizomenon flosaquae (AF) and Microcystis aeruginosa (MA),on the photoreduction rate of Hg2+ under various light conditions.The experimental results showed that percentage reduction of Hg2+ was significantly influenced by radiation wavelengths,and dramatically decreased with the presence of algae.The highest percentage reduction of Hg2+ was induced by UV-A,followed by UV-B,visible light and dark for both living and dead AF,and the order was dark > UV-A > UV-B > visible light for both living and dead MA.There were two aspects,i.e.,energy and attenuation rate of light radiation and excrementitious generated from algae metabolisms,were involved in the processes of Hg2+ photoreduction with the presence of algae under different light conditions.The percentage reduction of Hg2+ decreased from 15% to 11% when living and dead AF concentrations increased by 10 times (from 106 to 105 cells/mL),and decreased from11% to ~9% in the case of living and dead MA increased.Algae can adsorb Hg2+ and decrease the concentration of free Hg2+,thus inhibiting Hg2+ photoreduction,especially under the conditions with high concentrations of algae.No significant differences were found in percentage reduction of Hg2+ between living and dead treatments of algae species.The results are of great importance for understanding the role of algae in Hg2+ photoreduction.
基金supported by the National Natural Science Foundation of China (Nos. 51778229 , 21307032 )the Fundamental Research Funds for the Central Universities (No. JKB012015019 )。
文摘The stronger coordination ability of mercury ions with organic ligands than the metal ions in metal organic framework(MOFs) provides an accessible way to separate mercury ions from solution using specific MOFs. In this study, a Co-based MOF(ZIF-67, Co(mIM)) was synthesized. It did not introduce specific functional groups, such as-SH and-NH, into its structure through complicated steps. It separate Hgfrom wastewater with a new strategy, which utilized the stronger coordination ability of Hgwith the nitrogen atom on the imidazole ring of the organic ligand than the Coions. Hgreplaced Conodes from ZIF-67 and formed a more stable precipitate with m IM. The experimental results showed that this new strategy was efficient. ZIF-67 exhibited Hgadsorption capacity of 1740 mg/g, much higher than the known MOFs sorbents. m IMs is the reaction center and ZIF-67 can improve its utilization. The sample color faded from purple to white due to the loss of cobalt ion. It is a great feature of ZIF-67 that allows users to judge whether the sorbent is deactivated intuitively. ZIF-67 can be sustainable recycled by adding organic ligands to the solution after treatment due to its simple synthesis method at room temperature. It’s a high-efficient and sustainable sorbent for Hgseparation from wastewater.
基金Supported by the Start-Up Funds of Xi’an Polytechnic University under Grant No BS1211the Scientific Research Program Funded by Shaanxi Provincial Education Department under Grant No 2013JK0679
文摘Based on the two-component relativistic effective core potential and matched basis sets cc-pwcvnz-pp （n=Q, 5）, combining the completed basis-set extrapolation of electronic correlation energy and the fourth-order polynomial fitting technique, the bond length and spectroscopic constants of Hg2 are studied by the coupled cluster theory with spin-orbit coupling. Spin-orbit coupling is included in the post Hartree-Fock procedure, i.e., in the coupled- cluster iteration, to obtain more reliable theoretical results. The results show that our theoretical values agree with the experimental values very well and will be helpful to understand the spectral character of Hg2.
文摘Mesoporous silica materials with uniform channels containing functionalized organic monolayers have been synthesized by grafting a thiol functional group, （3-Mercaptopropyl） trimethoxysilane （MPTMS）. A new approach to heavy metal ion adsorbents based on the covalent grafting of MPTMS groups to the framework pore walls of mesoporous silica molecular sieves has been developed and investigated with regard to hydroxyl group densities, channel dimensions, morphologies and reaction conditions. Results show that the ordered mesostructures of functionalized samples were retained after modification and the thiol functional group was immobilized mainly inside the mesopore channel. The relative surface coverage of the monolayer can be systematically varied up to 95%. The functionalized hybrid materials show exceptional selectivity and capacity for removing mercury from aqueous waste stream with distribution coefficients up to 435,000. The regenerated material show high mercury ion uptake capacity of 2.87 mmol/g （86.5%）.
