A new metal-organic framework(MOF) with the chemical formula of [Ni_(2) F_2(4,4'-Bipy)_(2)(H_(2) O)_(2)](VO_(3))_(2)·8 H_(2) O was introduced to adsorb Pb(Ⅱ) with the highest capacity.The sorbent was charact...A new metal-organic framework(MOF) with the chemical formula of [Ni_(2) F_2(4,4'-Bipy)_(2)(H_(2) O)_(2)](VO_(3))_(2)·8 H_(2) O was introduced to adsorb Pb(Ⅱ) with the highest capacity.The sorbent was characterized by thermogravimetric analysis(TGA),infrared spectroscopy(FT-IR),field-emission scanning electron microscopy(FESEM),energy-dispersive Xray(EDX),and elemental analysis.The optimum conditions were obtained by a face-centered central composite design(FCCD) as follows:adsorbent dosage(m)=1.2 mg, initial concentration of Pb(Ⅱ)(C)=390 mg·L^(-1),and pH=5.According to the Langmuir model(R~2=0.9999),the maximum monolayer uptake capacity of lead(Ⅱ) is 2400.7 mg·g^(-1),which is the highe st observed amount for lead(Ⅱ) adsorption.Neither of the old adsorbents for lead(Ⅱ)has the uptake capacity over 2000 mg·g^(-1).The model of pseudo-second-order describes well the process kinetics.The adsorption process of lead(Ⅱ) is independent of temperature changes.This compound can adsorb lead(Ⅱ) from tap water.In addition to introducing a new MOF with the highest uptake capacity for removal of Pb(Ⅱ) that is the outright novelty of this study,the concurrent modeling of both the removal percent(R) and the uptake capacity(q) is another important advantage.Because it achieves the more economical and favorable optimum conditions in comparison with the single optimization of each response.展开更多
The complexes of four ferrocenylaldehyde aroylhydrazones with lead(Ⅱ) were synthesized and characterized. Their compositions, bonding forms and properties were researched by means of elemental analysis, IR, UV Vis,...The complexes of four ferrocenylaldehyde aroylhydrazones with lead(Ⅱ) were synthesized and characterized. Their compositions, bonding forms and properties were researched by means of elemental analysis, IR, UV Vis, 1H NMR spectra, thermal analysis and molar conductance. The free ligands which existed in the keto form coordinated to lead(Ⅱ) in the enol form to form neutral complexes. The molar ratio of the ligand to lead(Ⅱ) is 2∶1 and the thermal stability of the complex is higher than that of the corresponding ligand because of the formation of the stable chelate ring. The ligands and the complexes are all non electrolytes.展开更多
[Pb（TPT）（μ-I）2PbI2（μ-I）2Pb（TPT）] 1 （TPT is the abbreviation of 3,5,6-tris（2- pyridyl）-1,2,4-triazine ligand） has been synthesized and characterized by elemental analysis, IR, J H- NMR spectroscopy and st...[Pb（TPT）（μ-I）2PbI2（μ-I）2Pb（TPT）] 1 （TPT is the abbreviation of 3,5,6-tris（2- pyridyl）-1,2,4-triazine ligand） has been synthesized and characterized by elemental analysis, IR, J H- NMR spectroscopy and studied by thermal and electrochemical properties as well as X-ray crystallography. The single-crystal X-ray data show two different kinds of Pb2＋ ions in 1 with coordination numbers of six, Pbl = PbI6, and five, Pb2 = PbN312, with holodirected and hemidirected coordination spheres, respectively. The supramolecular features in 1 are negotiated through the weak but directional Pb...I, C-H...N and C-H...I interactions and aromatic π-π stacking interactions.展开更多
A two-dimensional coordination polymer, [Pb（bmzbc）2]n（1）（Hbmzbc =4-benzimidazole-1-yl-benzoic acid）, has been synthesized by the solvothermal reaction of Pb（NO3）2 with Hbmzbc at 120 ℃ in ethanol solvent. Comp...A two-dimensional coordination polymer, [Pb（bmzbc）2]n（1）（Hbmzbc =4-benzimidazole-1-yl-benzoic acid）, has been synthesized by the solvothermal reaction of Pb（NO3）2 with Hbmzbc at 120 ℃ in ethanol solvent. Compound 1 has been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetry analysis, and IR spectrum. Compound 1 crystallizes in the orthorhombic system, space group Pccn, with a = 12.5801（7）, b = 20.0795（11）, c = 9.1830（6） ？, V = 2319.6（2） A^3, Z = 4, C（28）H（18）N4O4Pb, Mr = 681.65, Dc = 1.952 g/cm^3, μ = 7.319 mm^-1, F（000） = 1312, the final R = 0.0336 and wR = 0.0965 for 1699 observed reflection with I 〉 2σ（I）. In 1, the bmzbc^– ligands bridge the Pb（Ⅱ） ions to generate a 2-D sheet with（4, 4） topology. The complex exhibits turquoise photoluminescent emission with a maximum at 480 nm upon excitation at 300 nm.展开更多
Solvothermal reaction of Pb（NO3）2·6H2O with rigid linear ligand terephthalic acid（H2pta） in N,N-dimethylformamide（DMF） produced a new three-dimensional（3D） lead（Ⅱ）coordination polymer[Pb2（pta）1.5（μ...Solvothermal reaction of Pb（NO3）2·6H2O with rigid linear ligand terephthalic acid（H2pta） in N,N-dimethylformamide（DMF） produced a new three-dimensional（3D） lead（Ⅱ）coordination polymer[Pb2（pta）1.5（μ4-OH）（DMF）]n 1,and its structure was characterized by single-crystal X-ray diffraction analyses.In polymer 1,the μ4-OH bridges the nearby lead（Ⅱ） ions into an infinite one-dimensional（1D） chain,and then the organic ligand pta^2- joins the neighbored chains into a 3D structure by two similar connection modes in different configurations.The solid-state photoluminescent studies revealed that 1 exhibits a strong greenish emission mainly originating from ligand-to-metal charge transfer between the delocalized π bonds of the aromatic carboxylate ligand pta^2- and the p orbitals of the Pb^2＋ centers.展开更多
Lead (Ⅱ)-binding properties of rabbit liver thionein 2 (apo-MT2) have been studied.Two kinds of complexes. Pb7-MT and Ph7-MT', are observed upon the binding of Ph2+ to apo-MTat different PH. From their characteri...Lead (Ⅱ)-binding properties of rabbit liver thionein 2 (apo-MT2) have been studied.Two kinds of complexes. Pb7-MT and Ph7-MT', are observed upon the binding of Ph2+ to apo-MTat different PH. From their characteristic peaks in UV and CD spectra. it is deduced that Ph2+ inPh7-MT is coordinated by four sulfhydryl groups in Td microsymmetry, while multiplecoordination types including two-coordination maybe present in Ph7-MT'展开更多
One new three-dimensional polymeric PbⅡ complex,[Pb3(CTA)2(H2 O)2]n·nH2O(1),(H3 CTA = cis,cis-1,3,5-cyclohexanetricarboxylic acid), has been synthesized. Single-crystal X-ray diffraction analyses reveal that com...One new three-dimensional polymeric PbⅡ complex,[Pb3(CTA)2(H2 O)2]n·nH2O(1),(H3 CTA = cis,cis-1,3,5-cyclohexanetricarboxylic acid), has been synthesized. Single-crystal X-ray diffraction analyses reveal that complex 1 has a three-dimensional architecture consisting of Pb2O2 dimeric building units, which shows two types of PbⅡ centers(eight-coordinated Pb(1),six-coordinated Pb(2) and Pb(3)). The eight-coordinated Pb(1) center possesses a stereochemically ‘inactive’ electron lone pair, and the coordination sphere is holodirected. However, the arrangement of oxygen atoms around Pb(2) and Pb(3) suggests a gap or hole in the coordination geometry. The stereo-chemically ‘active’ electron lone pairs of Pb(2) and Pb(3) possibly occupy these ‘holes’ and their coordination spheres are hemidirected. Its properties have been determined by FT-IR spectra, elemental analyses and thermogravimetric analyses(TGA). Solid-state luminescent properties of 1 also have been determined, indicating strong fluorescent emissions.展开更多
The authors presented a simple colorimetric assay for the detection of toxic heavy metal lead（Ⅱ） ion（Pb2＋） Pentapeptide, cysteine-alanine-leacine-asparagine-asparagine（CALNN）, functionalized gold nanoparticles...The authors presented a simple colorimetric assay for the detection of toxic heavy metal lead（Ⅱ） ion（Pb2＋） Pentapeptide, cysteine-alanine-leacine-asparagine-asparagine（CALNN）, functionalized gold nanoparticles（GNPs） were aggregated in the presence of the divalent metal ion in solution by an ion-templated chelation process, which caused an easily measurable change in the absorption spectrum of the particles. Typically, mono-dispersing GNPs exhibit an absorption band at 522 nm, corresponding to a red color solution, while aggregated GNPs have it at longer wavelengths, corresponding to a purple or blue color solution. The chelation/aggregation process is reversible via the addition of a strong metal ion chelator such as EDTA. Highly selective and sensitive detection of Pb^2＋ in aqueous solution is thus provided. A detection limit of 0.1 μmol/L of Pb^2＋ was demonstrated.展开更多
文摘A new metal-organic framework(MOF) with the chemical formula of [Ni_(2) F_2(4,4'-Bipy)_(2)(H_(2) O)_(2)](VO_(3))_(2)·8 H_(2) O was introduced to adsorb Pb(Ⅱ) with the highest capacity.The sorbent was characterized by thermogravimetric analysis(TGA),infrared spectroscopy(FT-IR),field-emission scanning electron microscopy(FESEM),energy-dispersive Xray(EDX),and elemental analysis.The optimum conditions were obtained by a face-centered central composite design(FCCD) as follows:adsorbent dosage(m)=1.2 mg, initial concentration of Pb(Ⅱ)(C)=390 mg·L^(-1),and pH=5.According to the Langmuir model(R~2=0.9999),the maximum monolayer uptake capacity of lead(Ⅱ) is 2400.7 mg·g^(-1),which is the highe st observed amount for lead(Ⅱ) adsorption.Neither of the old adsorbents for lead(Ⅱ)has the uptake capacity over 2000 mg·g^(-1).The model of pseudo-second-order describes well the process kinetics.The adsorption process of lead(Ⅱ) is independent of temperature changes.This compound can adsorb lead(Ⅱ) from tap water.In addition to introducing a new MOF with the highest uptake capacity for removal of Pb(Ⅱ) that is the outright novelty of this study,the concurrent modeling of both the removal percent(R) and the uptake capacity(q) is another important advantage.Because it achieves the more economical and favorable optimum conditions in comparison with the single optimization of each response.
文摘The complexes of four ferrocenylaldehyde aroylhydrazones with lead(Ⅱ) were synthesized and characterized. Their compositions, bonding forms and properties were researched by means of elemental analysis, IR, UV Vis, 1H NMR spectra, thermal analysis and molar conductance. The free ligands which existed in the keto form coordinated to lead(Ⅱ) in the enol form to form neutral complexes. The molar ratio of the ligand to lead(Ⅱ) is 2∶1 and the thermal stability of the complex is higher than that of the corresponding ligand because of the formation of the stable chelate ring. The ligands and the complexes are all non electrolytes.
基金Support of this investigation by Payame Noor University
文摘[Pb（TPT）（μ-I）2PbI2（μ-I）2Pb（TPT）] 1 （TPT is the abbreviation of 3,5,6-tris（2- pyridyl）-1,2,4-triazine ligand） has been synthesized and characterized by elemental analysis, IR, J H- NMR spectroscopy and studied by thermal and electrochemical properties as well as X-ray crystallography. The single-crystal X-ray data show two different kinds of Pb2＋ ions in 1 with coordination numbers of six, Pbl = PbI6, and five, Pb2 = PbN312, with holodirected and hemidirected coordination spheres, respectively. The supramolecular features in 1 are negotiated through the weak but directional Pb...I, C-H...N and C-H...I interactions and aromatic π-π stacking interactions.
基金Supported by the National Natural Science Foundation of China(No.21361011 and 21101081)the Natural Science Foundation of Jiangxi Province(No.20151BAB203002)Science Founds of State key laboratory of Structural Chemistry(20130011)
文摘A two-dimensional coordination polymer, [Pb（bmzbc）2]n（1）（Hbmzbc =4-benzimidazole-1-yl-benzoic acid）, has been synthesized by the solvothermal reaction of Pb（NO3）2 with Hbmzbc at 120 ℃ in ethanol solvent. Compound 1 has been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetry analysis, and IR spectrum. Compound 1 crystallizes in the orthorhombic system, space group Pccn, with a = 12.5801（7）, b = 20.0795（11）, c = 9.1830（6） ？, V = 2319.6（2） A^3, Z = 4, C（28）H（18）N4O4Pb, Mr = 681.65, Dc = 1.952 g/cm^3, μ = 7.319 mm^-1, F（000） = 1312, the final R = 0.0336 and wR = 0.0965 for 1699 observed reflection with I 〉 2σ（I）. In 1, the bmzbc^– ligands bridge the Pb（Ⅱ） ions to generate a 2-D sheet with（4, 4） topology. The complex exhibits turquoise photoluminescent emission with a maximum at 480 nm upon excitation at 300 nm.
基金supported by the Natural Science Foundation of Fujian province(2015J01033)Industry-University Cooperation Key Project of Science and Technology of Fujian Province(2012H6002)
文摘Solvothermal reaction of Pb（NO3）2·6H2O with rigid linear ligand terephthalic acid（H2pta） in N,N-dimethylformamide（DMF） produced a new three-dimensional（3D） lead（Ⅱ）coordination polymer[Pb2（pta）1.5（μ4-OH）（DMF）]n 1,and its structure was characterized by single-crystal X-ray diffraction analyses.In polymer 1,the μ4-OH bridges the nearby lead（Ⅱ） ions into an infinite one-dimensional（1D） chain,and then the organic ligand pta^2- joins the neighbored chains into a 3D structure by two similar connection modes in different configurations.The solid-state photoluminescent studies revealed that 1 exhibits a strong greenish emission mainly originating from ligand-to-metal charge transfer between the delocalized π bonds of the aromatic carboxylate ligand pta^2- and the p orbitals of the Pb^2＋ centers.
文摘Lead (Ⅱ)-binding properties of rabbit liver thionein 2 (apo-MT2) have been studied.Two kinds of complexes. Pb7-MT and Ph7-MT', are observed upon the binding of Ph2+ to apo-MTat different PH. From their characteristic peaks in UV and CD spectra. it is deduced that Ph2+ inPh7-MT is coordinated by four sulfhydryl groups in Td microsymmetry, while multiplecoordination types including two-coordination maybe present in Ph7-MT'
基金supported by the Fundamental Research Funds for the Central Universities(No.3122017071)Training Program of Innovation and Entrepreneurship for Undergraduates(No.201710059010)+1 种基金Open Project of Tianjin Key Lab Struct.&Performance Funct Mol(Tianjin Normal Univ.)National Natural Science Foundation of China(No.21501196)
文摘One new three-dimensional polymeric PbⅡ complex,[Pb3(CTA)2(H2 O)2]n·nH2O(1),(H3 CTA = cis,cis-1,3,5-cyclohexanetricarboxylic acid), has been synthesized. Single-crystal X-ray diffraction analyses reveal that complex 1 has a three-dimensional architecture consisting of Pb2O2 dimeric building units, which shows two types of PbⅡ centers(eight-coordinated Pb(1),six-coordinated Pb(2) and Pb(3)). The eight-coordinated Pb(1) center possesses a stereochemically ‘inactive’ electron lone pair, and the coordination sphere is holodirected. However, the arrangement of oxygen atoms around Pb(2) and Pb(3) suggests a gap or hole in the coordination geometry. The stereo-chemically ‘active’ electron lone pairs of Pb(2) and Pb(3) possibly occupy these ‘holes’ and their coordination spheres are hemidirected. Its properties have been determined by FT-IR spectra, elemental analyses and thermogravimetric analyses(TGA). Solid-state luminescent properties of 1 also have been determined, indicating strong fluorescent emissions.
基金Supported by the National Natural Science Foundation of China(No.20675080)the Program of Chinese Academy of Sciences Hundred Talents(No.KJCX2-YW-H11)
文摘The authors presented a simple colorimetric assay for the detection of toxic heavy metal lead（Ⅱ） ion（Pb2＋） Pentapeptide, cysteine-alanine-leacine-asparagine-asparagine（CALNN）, functionalized gold nanoparticles（GNPs） were aggregated in the presence of the divalent metal ion in solution by an ion-templated chelation process, which caused an easily measurable change in the absorption spectrum of the particles. Typically, mono-dispersing GNPs exhibit an absorption band at 522 nm, corresponding to a red color solution, while aggregated GNPs have it at longer wavelengths, corresponding to a purple or blue color solution. The chelation/aggregation process is reversible via the addition of a strong metal ion chelator such as EDTA. Highly selective and sensitive detection of Pb^2＋ in aqueous solution is thus provided. A detection limit of 0.1 μmol/L of Pb^2＋ was demonstrated.
