The complexity of communication and coordination stemming from teams responsible for adjusting interdependent parameters of components is a fundamental feature in the aircraft engine remanufacturing engineering projec...The complexity of communication and coordination stemming from teams responsible for adjusting interdependent parameters of components is a fundamental feature in the aircraft engine remanufacturing engineering project. To manage coordination complexity, the features of the remanufacturing process of aircraft engine are analyzed and a systematic method is presented to measure and optimize the dependency between coupled components.Furthermore, quantitative models are built based on Design Structure Matrix(DSM) models to measure dependency strengths related to the parameter features of the components. Also, a two-stage DSM clustering criteria is used to reduce the complexity of an organization. An industrial example is provided to illustrate the proposed models. The results showed that the proposed approach can reduce total coordination complexity.展开更多
Narrow solar-light response range and rapid charges recombination are the main technical barriers in TiO_(2) photocatalysis technology.To overcome these restrictions,in this work we synthesized a novel binuclear gadol...Narrow solar-light response range and rapid charges recombination are the main technical barriers in TiO_(2) photocatalysis technology.To overcome these restrictions,in this work we synthesized a novel binuclear gadolinium(Ⅲ) coordination complex,[Gd_(2)(DPDB)_6(DMF)_6(H_(2)O_()2)](DPDB=[(4-dimethylamino)phenyldiazenyl] benzenesulfonate),which was used as an inorganic sensitizer for boosting the visible light-harvesting and quantum efficiency of TiO_(2) supported-reduced graphene oxide(rGO) nanocomposite.Crystal structure of [Gd_(2)(DPDB)_6(DMF)_6(H_(2)O)_(2)](Gd-CMP) was determined from single-crystal X-ray diffraction data,which indicates three-dimensional(3D) supramolecular architecture through hydrogen bonding and CH…π_(ph) interactions.The prepared nanohybrid(Gd-CMP/TG) reveals significantly enhanced visible-light-induced photocatalytic activity for degradation of acetaminophen(ACT).The complete removal of 10 mg/L ACT is achieved over Gd-CMP/TG,and the corresponding rate constant of ACT degradation of nanohybrid is 40-fold higher than that of bare TiO_(2).In prepared ternary nanohybrid,metal-coordination sensitizer(Gd-CMP) acts as an electron donor,and at the same time,rGO serves as an electron acceptor,and the synergistic effect between them efficiently enhances charges separation and inhibits e/h pair recombination in the hybridized species.The radical scavenger tests indicate that the photo-induced O_(2)^(-·) radicals dominate ACT degradation.On the basis of the experimental results and calculated energy of electronic levels,a possible mechanism for the improved photocatalytic activity is discussed.展开更多
With the development of coal chemical industry,large amounts of naphthalene and n-butene are produced,and converting them into high value-added products through alkylation has gained particular importance and interest...With the development of coal chemical industry,large amounts of naphthalene and n-butene are produced,and converting them into high value-added products through alkylation has gained particular importance and interest.In this work,liquid coordination complexes(LCCs)were used as acid catalysts for the first time in the naphthalene alkylation reaction under mild conditions to obtain multibutylnaphthalenes with high yield.Various reaction conditions were thoroughly investigated.The LCC consisting of urea and AlCl_(3) showed excellent catalytic performance under optimal reaction conditions,giving 100%conversion of naphthalene and 99.66%selectivity towards multi-butylnaphthalenes.Combining the catalyst properties and catalytic results,a plausible reaction mechanism was proposed.The lubricating properties of the synthesized products were investigated for their potential application as lubricating base oils.The synthesized multi-butylnaphthalenes showed comparable physicochemical properties and tribological performances as the commercial cycloalkyl base oil.展开更多
A new coordination complex [In(pda)1.5(bpy)]n (1, H2pda = 1,4-phenylenediacetic acid, bpy = 2,2'-bipyridine) has been synthesized under hydrothermal conditions and characterized by IR spectrum, elemental analys...A new coordination complex [In(pda)1.5(bpy)]n (1, H2pda = 1,4-phenylenediacetic acid, bpy = 2,2'-bipyridine) has been synthesized under hydrothermal conditions and characterized by IR spectrum, elemental analysis, PXRD and single-crystal X-ray diffraction analysis. Crystal data for the title complex are as follows: monoclinic system, space group P21/n with a = 11.8015(7), b = 15.9551(10), c = 11.8858(8)A^°, β = 94.844(6)°, V = 2230.0(2) A^°3, Mr = 559.25, Z = 4, F(000) = 1124, Dc = 1.666 g/cm^3, μ(MoKα) = 1.106 mm^-1, R = 0.0269 and wR = 0.0569 for 4534 observed reflections with I 〉 2σ(I). Complex 1 displays a 3D supermolecular structure based on the 1D zizag chains. Fluorescence spectrum measurement indicates that complex 1 shows strong fluorescence emission with a maximum peak at 447 nm in the solid state at room temperature.展开更多
Two 1D coordination polymers[Ln2(dpdc)3(tpy)2·H2O]n[Ln=Nd 1,Yb 2,H2dpdc=2,2'-biphenyldicarboxylic acid and tpy=2,2':6',2''-terpyridine]and one dinuclear complex Er2(dpdc)2(Hdpdc)2(tpy)23 were ...Two 1D coordination polymers[Ln2(dpdc)3(tpy)2·H2O]n[Ln=Nd 1,Yb 2,H2dpdc=2,2'-biphenyldicarboxylic acid and tpy=2,2':6',2''-terpyridine]and one dinuclear complex Er2(dpdc)2(Hdpdc)2(tpy)23 were obtained via hydrothermal reactions and determined by X-ray diffraction analysis.The crystal structure data of 1 and 2 revealed that two coordination polymers were isostructural and possessed a 1D chain framework consisting of eight-coordinated Ln(III)centers.In the asymmetric unit,the two Er(III)ions in 3 were both nine-coordinated and had similar coordination environments.The Er(III)ions were bridged by dpdc2-ligands into dinuclear structures.The complexes were also characterized by IR spectra and thermogravimetric analysis.The solid fluorescence of 1 and 3 was also investigated at room temperature.展开更多
Two new hydrostable two-dimensional(2 D)uranyl coordination complexes[(UO_(2))_(5)(μ_(3)-O)_(2)(nbca)_(2)].7 H_(2)O(1)and[(UO_(2))_(3)(nbca)_(2)(H_(2)O)_(3)]·2 H_(2)O(2)(H_(3)nbca=5-nitro-1,2,3-benzenetricarboxy...Two new hydrostable two-dimensional(2 D)uranyl coordination complexes[(UO_(2))_(5)(μ_(3)-O)_(2)(nbca)_(2)].7 H_(2)O(1)and[(UO_(2))_(3)(nbca)_(2)(H_(2)O)_(3)]·2 H_(2)O(2)(H_(3)nbca=5-nitro-1,2,3-benzenetricarboxylic acid)were hydrothermal synthesized.Single-crystal structural refinements reveal that both of the two complexes were formed by the packing of 2D uranyl coordination sheets via the hydrogen bonds.The nbca ligand coordinating to the uranyl polyhedron centers constructed the 2D sheets.There are UO8 hexagonal bipyramids and UO7 pentagonal bipyramids in 1 while only U07 pentagonal bipyramids in 2.Photocatalytic degradation of rhodamine B(RhB)in aqueous solution was studied.Complex 2 possesses better performance than 1 with 96.2%of the RhB was degraded in only 60 min.Mechanism studies reveal that the dissolved oxygens are essential to the RhB degradation.The photocurrent density of 2 is more stable than that of 1,which indicating the stronger ability to separate photoexcited electrons and hole pairs of 2.展开更多
Two coordinate reactions,NdCl 3·6H 2O(s)+3CCl 3COOH(s)(or TCA)=Nd(TCA)3·3H 2O(s)+3HCl(g)+3H 2O(l)and Nd(TCA)3·3H 2O(s)+2C 9H 7NO(s)=Nd(TCA)(C 9H 6NO)2(s)+2CCl 3COOH(s)+3H 2O(l),were studied by the class...Two coordinate reactions,NdCl 3·6H 2O(s)+3CCl 3COOH(s)(or TCA)=Nd(TCA)3·3H 2O(s)+3HCl(g)+3H 2O(l)and Nd(TCA)3·3H 2O(s)+2C 9H 7NO(s)=Nd(TCA)(C 9H 6NO)2(s)+2CCl 3COOH(s)+3H 2O(l),were studied by the classical solution calorimetry at 298.15K.The molar dissolution enthalpies of the reactants and the products in certain solvent(the first reaction in 1 mol·L-1 HCl,the second in a mixed solution consisting of absolute ethyl alcohol,dimethyl sulfoxide and 4 mol·L-1 HCl)were measured by using an isoperibol calorimeter at 298.15K.From the results and other auxiliary quantities,the standard molar formation enthalpies of[Nd(TCA)3·3H 2O,s,298.15K]and[Nd(TCA)(C 9H 6NO)2,s,298.15K]are determined asΔfH m°[Nd(TCA)3·3H 2O,s,298.15K]=-3053.3 kJ·mol-1 andΔfH m°[Nd(TCA)(C 9H 6NO)2,s,298.15K]=-1355.6 kJ·mol-1.展开更多
A new coordination complex [Cd(pda)(pyz)(H2O)2]n(1, H2 pda = 1,4-phenylenediacetic acid, pyz = pyrazine) have been synthesized and structurally characterized. Crystal data for the title complex are as follows: orthorh...A new coordination complex [Cd(pda)(pyz)(H2O)2]n(1, H2 pda = 1,4-phenylenediacetic acid, pyz = pyrazine) have been synthesized and structurally characterized. Crystal data for the title complex are as follows: orthorhombic system, space group Ccmb with a = 11.5245(3) b = 19.5069(5) c = 11.4231(3) A, V = 2568.00(12) A3, Mr = 188.31, Z = 16, F(000) = 1480, Dc = 1.948 g/cm3, μ(Mo Kα) = 1.725 mm-1, R = 0.0195 and w R = 0.0462 for 1357 observed reflections with I 】 2σ(I). In the title complex, the central Cd(II) ion is located in a distorted octahedral coordination environment. Two Cd(II) ions are bridged by two pda2- ligands and one pyz ligand to form a bi-loop structure. Luminescent property of the complex has also been studied.展开更多
Two cobalt coordination polymers with the same 2D structure have been hydrothermally synthesized based on two bifunctional ligands with tetrazole and phosphonate(phosphonic acid) groups,namely,diethyl 4-(2H-1,2,3,4...Two cobalt coordination polymers with the same 2D structure have been hydrothermally synthesized based on two bifunctional ligands with tetrazole and phosphonate(phosphonic acid) groups,namely,diethyl 4-(2H-1,2,3,4-tetrazol-5-yl) benzylphosphonate(C_2H_5-L1) and 4-(2H-1,2,3,4-tetrazol-5-yl)benzylphosphonic acid(H_2L2). The structures of the two complexes are characterized by elemental analysis,IR,TGA and X-ray single-crystal/powder diffraction. The pink block crystals of complex [Co(L1)(H_2O)]·H_2O(1) belong to the monoclinic system,space group C2/m with a = 20.8390(11),b = 7.2695(3),c = 10.0156(6) A,β = 109.773(7)°,V = 1427.80(13) A^3,Z = 4,D_c = 1.680 mg/cm^-3,M_r = 361.16,F(000) = 740,R = 0.0316 and wR = 0.0826 for 1702 observed reflections(I 〉 2σ(I)). The purple block crystals of complex [Co(L2)(H_2O)]·2H_2O(2) also belong to the monoclinic system,space group C2/c with a = 25.5382(16),b = 7.3844(3),c = 15.1925(11) A,β = 124.238(9)°,V = 2368.6(2) A^3,Z = 8,D_c = 1.969 mg/cm^-3,M_r = 351.12,F(000) = 1432,R = 0.0475,wR = 0.1617 for 2088 observed reflections(I 〉 2σ(I)). Both the nitrogen atoms of tetrazole group and oxygen atoms of phosphonate(phosphonic acid) groups in the ligands coordinated with the metal cobalt. The magnetic property of complex 1 is also investigated.展开更多
With the increase of people’s demand,it is extremely desired for developing high-safety,widetemperature-range and high-energy-density lithium batteries,but huge challenges are remained due to shrinkage and combustion...With the increase of people’s demand,it is extremely desired for developing high-safety,widetemperature-range and high-energy-density lithium batteries,but huge challenges are remained due to shrinkage and combustion of commonly used polyolefin separators at high temperatures,as well as narrow usable temperature range and high flammability of conventionally commercialized liquid electrolytes.In this work,we report a multifunctional separator mainly consisting of Zn^(2+)-phytate coordination complex nanoparticles and bacterial cellulose nanofibers,named the BZP separator,which possesses high porosity,excellent thermotolerance,good flame retardancy,abilities of anion binding and Ni^(2+)capturing.Through cooperating with the fluoride-free wide-temperature-range electrolyte,Li//LiFePO_(4) cells not only deliver discharge capacities of 110.39 mA h g^(-1)and 113.25 mA h g^(-1)after 2200 cycles (2 C) and1600 cycles (5 C) at 25℃,with capacity retentions of 76.59%and 86.09%,respectively,but also exhibit excellent cycling performance at 80℃ and-40℃.Significantly,the Li//NCM811 cell with a loading of7.8 mg cm^(-2)delivers a discharge capacity of 146.64 mA h g^(-1)after 200 cycles at 0.5 C,with a capacity retention of 89.03%.In addition,pouch cells can work at 120℃ and have low flammability.展开更多
By simulating the electron paramagnetic resonance (EPR) and optical spectra on the basis of the 120 × 120 complete energy matrix, this paper determines the local lattice structure parameters R1 and R2 for MCl...By simulating the electron paramagnetic resonance (EPR) and optical spectra on the basis of the 120 × 120 complete energy matrix, this paper determines the local lattice structure parameters R1 and R2 for MCl:V2+ (M=Na, K, Rb) systems at 77K, 195 K and RT (room temperature 295 K or 302 K), respectively. The theoretical results indicate that there exists a compressed distortion in MCl:V2+ systems. Meanwhile, it finds that the structure parameters R1, R2 and |△R|( = R1 - R2) increase with the rising temperature. Subsequently, from the analysis it concludes that the relation of EPR parameter D vs. △R is approximately linear. Finally, the effects of orbital reduction factor k on the g factors for the three systems have been discussed.展开更多
Two new transition metal compounds, [Mn(dpa)2(tmd)2]n (1, H2dpa = 4-hydroxy-phenyl-acetic acid, tmd = 4,4-trimethylenedipyridine) and [Co4(dpa)6(tmd)4(H2O)4]n·nH2O·nCl2 (2), have been synthesiz...Two new transition metal compounds, [Mn(dpa)2(tmd)2]n (1, H2dpa = 4-hydroxy-phenyl-acetic acid, tmd = 4,4-trimethylenedipyridine) and [Co4(dpa)6(tmd)4(H2O)4]n·nH2O·nCl2 (2), have been synthesized by hydrothermal synthesis. Compound 1 crystallizes in the monoclinic system, space group P21/n with a = 9.828(3), b = 17.493(5), c = 11.616(4), β = 110.146(6)o, V = 1874.9(10)3, C42H42MnN4O6, Mr = 753.74, Z = 2, Dc = 1.335 g/cm3, μ = 0.406 mm-1, F(000) = 790, the final R = 0.1047 and wR = 0.2021 for 2698 observed reflections (I 〉 2σ(I)). Compound 2 crystallizes in the monoclinic system, space group P21/c with a = 11.7214(13), b = 17.1582(19), c = 24.625(3), β = 103.055(3)o, V = 4824.4(9)3, C100H104Cl2Co4N8O23, Mr = 2094.55, Z = 2, Dc = 1.443 g/cm3, μ = 0.809 mm-1, F(000) = 2180, the final R = 0.0550 and wR = 0.0673 for 4104 observed reflections (I 〉 2σ(I)). These complexes were characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. The structural analyses show that the two compounds are both one-dimensional chain structures. However, compounds 1 and 2 form threedimensional supramolecular structures by hydrogen bonds, respectively.展开更多
Two new cobalt(II) coordination complexes, namely [Co(HL)2(biim)(H2O)2]n·n H2O(1) and [Co(Et L)2(biim)]n·3 n(H2O)·2 n(Et HL)(2)(H2L =(fluorene-9,9-diyl)dipropanoic acid, biim = 1,...Two new cobalt(II) coordination complexes, namely [Co(HL)2(biim)(H2O)2]n·n H2O(1) and [Co(Et L)2(biim)]n·3 n(H2O)·2 n(Et HL)(2)(H2L =(fluorene-9,9-diyl)dipropanoic acid, biim = 1,3-bis(imidazol-1-yl)butane), have been synthesized using the same starting reactants but different solvent medium. The two complexes exhibit distinctly different structures. Compound 1 exhibits a one-dimensional linear chain structure. However, complex 2 reveals a one-dimensional zigzag chain structure. Thermogravimetric analyses(TGA) and luminescent properties of these two complexes have been discussed.展开更多
The 1-D chain coordination complex of {[Mn2(HCAM)3(H2bipy)]·5H2O}n (H3CAM = 4-hydroxypyridine-2,6-dicarboxylic acid, bipy = 4,4'-bipyridine) has been synthesized by the reaction of 4-hydroxypyridine-2,6-di...The 1-D chain coordination complex of {[Mn2(HCAM)3(H2bipy)]·5H2O}n (H3CAM = 4-hydroxypyridine-2,6-dicarboxylic acid, bipy = 4,4'-bipyridine) has been synthesized by the reaction of 4-hydroxypyridine-2,6-dicarboxylic acid, 4,4'-bipyridine and manganese carbonate under hydrothermal conditions, and its crystal structure was determined by X-ray diffraction method The crystal belongs to the monoclinic system, space group P21/n with a = 10.110(2), b = 20.159(4), c = 17.861(4)A,β = 99.67(3)°, V = 3.5884(12) nm3, Mr= 901.47, Z = 4, Dc= 1.669 g.cm^-3, μ= 0.798 mm^-1, F(000) = 1840, the final R = 0.0713 and ωR = 0.1853. The complex forms a 1-D chain bridged by HCAM, protonated 4,4-bipyridines link the 1-D chains to construct 2-D networks via N-H...O hydrogen bonds, and networks are further extended via π-π stacking and hydrogen bonds into 3-D supramolecular framework.展开更多
A novel coordination complex,{[Cd)2(C(20)H(10)O5)2(H2O)4]·10H2O}n,has been synthesized based on fluorescein(2-(6-hydroxy-3-oxo-3 H-xanthen-9-yl) benzoic acid) and systematically characterized by elem...A novel coordination complex,{[Cd)2(C(20)H(10)O5)2(H2O)4]·10H2O}n,has been synthesized based on fluorescein(2-(6-hydroxy-3-oxo-3 H-xanthen-9-yl) benzoic acid) and systematically characterized by elemental analysis,infrared(IR) spectrum,thermo gravimetric analysis(TGA),powder X-ray diffraction(PXRD) and single-crystal X-ray diffraction.Compound 1 crystallizes in monoclinic,space group P2/n with a = 20.428(5),b = 8.084(2),c = 21.689(5)A,β = 96.360(5)°,Mr = 993.46,V = 3559.7(15)A^3,Z = 4,Dx = 1.845 g/cm^3,μ = 1.276 mm^-1,F(000) = 1974,GOOF = 1.044,λ(Mo Kα) = 0.71073 ?,the final R = 0.0553 and wR = 0.1720 for 7245 observed reflections with I 〉 2σ(I).展开更多
A novel tetrazylphosphonate ligand, namely ethyl 4-(2-ethyl-2H-1,2,3,4-tetrazol-5-yl) benzylphosphonate(Et-L), was designed and successfully achieved from p-cyano benzyl chloride, based on which a zinc coordinatio...A novel tetrazylphosphonate ligand, namely ethyl 4-(2-ethyl-2H-1,2,3,4-tetrazol-5-yl) benzylphosphonate(Et-L), was designed and successfully achieved from p-cyano benzyl chloride, based on which a zinc coordination polymer(1) with a 2D layer structure has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, TGA and X-ray single-crystal diffraction. The colorless block crystals of H_2L·H_2O were also obtained under the same hydrothermal conditions, which belongs to monoclinic system, space group P2_1/c with a = 13.3141(7), b = 5.1650(3), c = 21.9839(18) A, β = 115.307(5)°, V = 1366.69(15)A3, Z = 4, D_c = 1.391 mg/cm^(-3), Mr = 349.58, F(000) = 600, R = 0.0748 and wR = 0.1917 for 2392 observed reflections(I 〉 2σ(I)). The colorless block crystals of complex 1([Zn(L)(H_2O)]_n) also belong to monoclinic system, space group P2_1/c with a = 22.7464(10), b = 6.0430(3), c = 9.7704(4) ?, β = 92.525(4)°, V = 1341.70(10)A3, Z = 4, D_c = 1.731 mg/cm_(-3), M_r = 349.58, F(000) = 712, R = 0.0596 and wR = 0.1688 for 2357 observed reflections(I 〉 2σ(I)). Only the oxygen atoms of phosphonic group are coordinated with the metal zinc probably because the hydrogen atom of tetrazole has been substituted by ethyl group. Photoluminescence properties of the complex are also investigated.展开更多
A novel double-stranded trinuclear bis(tridipyrrin)zinc(Ⅱ)complex,constructed from a linearπ-conjugated tridipyrrin ligand,was synthesized and characterized.The complex featuring six directly linked dipyrrin units e...A novel double-stranded trinuclear bis(tridipyrrin)zinc(Ⅱ)complex,constructed from a linearπ-conjugated tridipyrrin ligand,was synthesized and characterized.The complex featuring six directly linked dipyrrin units exhibits a stable double-helical structure with two non-superimposable P and M enantiomers,as confirmed by X-ray crystallography.Chirality was further demonstrated through HPLC separation and mirror-image circular dichroism(CD)spectra.The complex shows strong near-infrared(NIR)absorption and excellent solubility in various solvents,attributed to its sterically hindered structure.Spectroscopic,electrochemical,and theoretical studies revealed its unique electronic properties and redox behavior.This work advances the design of chiral NIR-active metallo-supramolecular systems and highlights potential applications in chiroptical mateials.展开更多
An unusual inorganic-organic hybrid hexatungstate complex [Cu(phen)3][W6O19] 1 (C36H24 CuN6O19W6, Mr= 2011.20) was hydrothermally synthesized and characterized by singlecrystal X-ray diffraction, IR spectrum, UV-V...An unusual inorganic-organic hybrid hexatungstate complex [Cu(phen)3][W6O19] 1 (C36H24 CuN6O19W6, Mr= 2011.20) was hydrothermally synthesized and characterized by singlecrystal X-ray diffraction, IR spectrum, UV-VIS spectrum and elemental analyses. This compound crystallizes in the monoclinic system, space group C2/c with a = 19.1005(11), b = 11.2585(11), c = 20.2867(15) A, β= 102.177(2)°, V= 4264.4 A^ 3, μ(MoKa) = 16.691 mm^-1, Dc = 3.133 g/cm^3, Z = 4, F(000) = 3628, the final R = 0.0338 and wR = 0.0798 for 4090 observed reflections with I 〉 2σ(I). The result of structure determination shows that the crystal structure is constructed from [W6O19]^2- cluster anions and [Cu(phen)3]^2+ complex fragments, which are held together into a three-dimensional network through hydrogen-bonding interactions.展开更多
This work reports a feasible synthesis of highly-dispersed Pt and Pt-Fe nanoparticles supported on multiwall carbon nanotubes (MWCNTs) without Fe and multiwall carbon nanotubes with iron (MWCNTs-Fe) which applied ...This work reports a feasible synthesis of highly-dispersed Pt and Pt-Fe nanoparticles supported on multiwall carbon nanotubes (MWCNTs) without Fe and multiwall carbon nanotubes with iron (MWCNTs-Fe) which applied as electrocatalysts for methanol electrooxidation. A Pt coordination complex salt was synthesized in an aqueous solution and it was used as precursor to prepare Pt/MWCNTs, Pt/MWCNTs-Fe, and Pt-Fe/MWCNTs using FeC12.4H20 as iron source which were named S 1, S2 and S3, respectively. The coordination complex of platinum (TOA)2PtC16 was obtained by the chemical reaction between (NH4)2PtC16 with tetraoctylammonium bromide (TOAB) and it was characterized by FT-IR and TGA. The materials were characterized by Raman spectroscopy, SEM, EDS, XRD, TEM and TGA. The electrocatalytic activity of Pt-based supported on MWCNTs in the methanol oxidation was investigated by cyclic voltammetry (CV) and chronoamperometry (CA). Pt-Fe/MWCNTs electrocatalysts showed the highest electrocatalytic activity and stability among the tested electrocatalysts due to that the addition of "Fe" promotes the OH species adsorption on the electrocatalyst surface at low potentials, thus, enhancing the activity toward the methanol oxidation reaction (MOR).展开更多
Chitosan–metal complexes have been widely studied in wastewater treatment, but there are still various factors in complex preparation which are collectively responsible for improving the adsorption capacity need to b...Chitosan–metal complexes have been widely studied in wastewater treatment, but there are still various factors in complex preparation which are collectively responsible for improving the adsorption capacity need to be further studied. Thus, this study investigates the factors affecting the adsorption ability of chitosan–metal complex adsorbents, including various kinds of metal centers, different metal salts and crosslinking degree. The results show that the chitosan–Fe( Ⅲ) complex prepared by sulfate salts exhibited the best adsorption efficiency(100%) for various dyes in very short time duration(10 min), and its maximum adsorption capacity achieved 349.22 mg/g. The anion of the metal salt which was used in preparation played an important role to enhance the adsorption ability of chitosan–metal complex. SO4^(2-) ions not only had the effect of crosslinking through electrostatic interaction with amine group of chitosan polymer, but also could facilitate the chelation of metal ions with chitosan polymer during the synthesis process.Additionally, the p H sensitivity and the sensitivity of ionic environment for chitosan–metal complex were analyzed. We hope that these factors affecting the adsorption of the chitosan–metal complex can help not only in optimizing its use but also in designing new chitosan–metal based complexes.展开更多
基金supported by the National Natural Science Foundation of China (No.71472013 No.71528005)
文摘The complexity of communication and coordination stemming from teams responsible for adjusting interdependent parameters of components is a fundamental feature in the aircraft engine remanufacturing engineering project. To manage coordination complexity, the features of the remanufacturing process of aircraft engine are analyzed and a systematic method is presented to measure and optimize the dependency between coupled components.Furthermore, quantitative models are built based on Design Structure Matrix(DSM) models to measure dependency strengths related to the parameter features of the components. Also, a two-stage DSM clustering criteria is used to reduce the complexity of an organization. An industrial example is provided to illustrate the proposed models. The results showed that the proposed approach can reduce total coordination complexity.
基金supported by grant No.98U587 from Abadan University of Medical Sciences。
文摘Narrow solar-light response range and rapid charges recombination are the main technical barriers in TiO_(2) photocatalysis technology.To overcome these restrictions,in this work we synthesized a novel binuclear gadolinium(Ⅲ) coordination complex,[Gd_(2)(DPDB)_6(DMF)_6(H_(2)O_()2)](DPDB=[(4-dimethylamino)phenyldiazenyl] benzenesulfonate),which was used as an inorganic sensitizer for boosting the visible light-harvesting and quantum efficiency of TiO_(2) supported-reduced graphene oxide(rGO) nanocomposite.Crystal structure of [Gd_(2)(DPDB)_6(DMF)_6(H_(2)O)_(2)](Gd-CMP) was determined from single-crystal X-ray diffraction data,which indicates three-dimensional(3D) supramolecular architecture through hydrogen bonding and CH…π_(ph) interactions.The prepared nanohybrid(Gd-CMP/TG) reveals significantly enhanced visible-light-induced photocatalytic activity for degradation of acetaminophen(ACT).The complete removal of 10 mg/L ACT is achieved over Gd-CMP/TG,and the corresponding rate constant of ACT degradation of nanohybrid is 40-fold higher than that of bare TiO_(2).In prepared ternary nanohybrid,metal-coordination sensitizer(Gd-CMP) acts as an electron donor,and at the same time,rGO serves as an electron acceptor,and the synergistic effect between them efficiently enhances charges separation and inhibits e/h pair recombination in the hybridized species.The radical scavenger tests indicate that the photo-induced O_(2)^(-·) radicals dominate ACT degradation.On the basis of the experimental results and calculated energy of electronic levels,a possible mechanism for the improved photocatalytic activity is discussed.
基金the National Natural Science Foundation of China(U1910202,21978194 and 21603256)the Natural Science Foundation of Shanxi Province(201801D121055)Program for the Shanxi Young Sanjin Scholar.
文摘With the development of coal chemical industry,large amounts of naphthalene and n-butene are produced,and converting them into high value-added products through alkylation has gained particular importance and interest.In this work,liquid coordination complexes(LCCs)were used as acid catalysts for the first time in the naphthalene alkylation reaction under mild conditions to obtain multibutylnaphthalenes with high yield.Various reaction conditions were thoroughly investigated.The LCC consisting of urea and AlCl_(3) showed excellent catalytic performance under optimal reaction conditions,giving 100%conversion of naphthalene and 99.66%selectivity towards multi-butylnaphthalenes.Combining the catalyst properties and catalytic results,a plausible reaction mechanism was proposed.The lubricating properties of the synthesized products were investigated for their potential application as lubricating base oils.The synthesized multi-butylnaphthalenes showed comparable physicochemical properties and tribological performances as the commercial cycloalkyl base oil.
基金Supported by the National Natural Science Foundation of China(No.21301069)the Natural Science Foundation of Shandong Province(No.ZR2012BQ004)
文摘A new coordination complex [In(pda)1.5(bpy)]n (1, H2pda = 1,4-phenylenediacetic acid, bpy = 2,2'-bipyridine) has been synthesized under hydrothermal conditions and characterized by IR spectrum, elemental analysis, PXRD and single-crystal X-ray diffraction analysis. Crystal data for the title complex are as follows: monoclinic system, space group P21/n with a = 11.8015(7), b = 15.9551(10), c = 11.8858(8)A^°, β = 94.844(6)°, V = 2230.0(2) A^°3, Mr = 559.25, Z = 4, F(000) = 1124, Dc = 1.666 g/cm^3, μ(MoKα) = 1.106 mm^-1, R = 0.0269 and wR = 0.0569 for 4534 observed reflections with I 〉 2σ(I). Complex 1 displays a 3D supermolecular structure based on the 1D zizag chains. Fluorescence spectrum measurement indicates that complex 1 shows strong fluorescence emission with a maximum peak at 447 nm in the solid state at room temperature.
基金Project supported by the Nonprofit Technology&Research in Zhejiang(2011C37010)sponsored by the K.C.Wong Magna Fund in Ningbo University,the Ningbo Municipal Natural Science Foundation(2010A610160)the Subject Object(xk1070)and Foundation(20111045)of Ningbo University
文摘Two 1D coordination polymers[Ln2(dpdc)3(tpy)2·H2O]n[Ln=Nd 1,Yb 2,H2dpdc=2,2'-biphenyldicarboxylic acid and tpy=2,2':6',2''-terpyridine]and one dinuclear complex Er2(dpdc)2(Hdpdc)2(tpy)23 were obtained via hydrothermal reactions and determined by X-ray diffraction analysis.The crystal structure data of 1 and 2 revealed that two coordination polymers were isostructural and possessed a 1D chain framework consisting of eight-coordinated Ln(III)centers.In the asymmetric unit,the two Er(III)ions in 3 were both nine-coordinated and had similar coordination environments.The Er(III)ions were bridged by dpdc2-ligands into dinuclear structures.The complexes were also characterized by IR spectra and thermogravimetric analysis.The solid fluorescence of 1 and 3 was also investigated at room temperature.
基金the support of National Science Foundations of China(No.21461001)the Project of Jiangxi Provincial Department of Education(Nos.GJJ170436 and GJJ180367)+1 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.19JKB150007)the Doctoral Scientific Research Foundation of East China University of Technology(No.DHBK2019143)。
文摘Two new hydrostable two-dimensional(2 D)uranyl coordination complexes[(UO_(2))_(5)(μ_(3)-O)_(2)(nbca)_(2)].7 H_(2)O(1)and[(UO_(2))_(3)(nbca)_(2)(H_(2)O)_(3)]·2 H_(2)O(2)(H_(3)nbca=5-nitro-1,2,3-benzenetricarboxylic acid)were hydrothermal synthesized.Single-crystal structural refinements reveal that both of the two complexes were formed by the packing of 2D uranyl coordination sheets via the hydrogen bonds.The nbca ligand coordinating to the uranyl polyhedron centers constructed the 2D sheets.There are UO8 hexagonal bipyramids and UO7 pentagonal bipyramids in 1 while only U07 pentagonal bipyramids in 2.Photocatalytic degradation of rhodamine B(RhB)in aqueous solution was studied.Complex 2 possesses better performance than 1 with 96.2%of the RhB was degraded in only 60 min.Mechanism studies reveal that the dissolved oxygens are essential to the RhB degradation.The photocurrent density of 2 is more stable than that of 1,which indicating the stronger ability to separate photoexcited electrons and hole pairs of 2.
基金the Hunan Provincial Educational Ministry Foundation of China(00C001)
文摘Two coordinate reactions,NdCl 3·6H 2O(s)+3CCl 3COOH(s)(or TCA)=Nd(TCA)3·3H 2O(s)+3HCl(g)+3H 2O(l)and Nd(TCA)3·3H 2O(s)+2C 9H 7NO(s)=Nd(TCA)(C 9H 6NO)2(s)+2CCl 3COOH(s)+3H 2O(l),were studied by the classical solution calorimetry at 298.15K.The molar dissolution enthalpies of the reactants and the products in certain solvent(the first reaction in 1 mol·L-1 HCl,the second in a mixed solution consisting of absolute ethyl alcohol,dimethyl sulfoxide and 4 mol·L-1 HCl)were measured by using an isoperibol calorimeter at 298.15K.From the results and other auxiliary quantities,the standard molar formation enthalpies of[Nd(TCA)3·3H 2O,s,298.15K]and[Nd(TCA)(C 9H 6NO)2,s,298.15K]are determined asΔfH m°[Nd(TCA)3·3H 2O,s,298.15K]=-3053.3 kJ·mol-1 andΔfH m°[Nd(TCA)(C 9H 6NO)2,s,298.15K]=-1355.6 kJ·mol-1.
基金Supported by the National Natural Science Foundation of China(No.21301069)the Natural Science Foundation of Shandong Province(No.ZR2012BQ004)
文摘A new coordination complex [Cd(pda)(pyz)(H2O)2]n(1, H2 pda = 1,4-phenylenediacetic acid, pyz = pyrazine) have been synthesized and structurally characterized. Crystal data for the title complex are as follows: orthorhombic system, space group Ccmb with a = 11.5245(3) b = 19.5069(5) c = 11.4231(3) A, V = 2568.00(12) A3, Mr = 188.31, Z = 16, F(000) = 1480, Dc = 1.948 g/cm3, μ(Mo Kα) = 1.725 mm-1, R = 0.0195 and w R = 0.0462 for 1357 observed reflections with I 】 2σ(I). In the title complex, the central Cd(II) ion is located in a distorted octahedral coordination environment. Two Cd(II) ions are bridged by two pda2- ligands and one pyz ligand to form a bi-loop structure. Luminescent property of the complex has also been studied.
基金Supported by the National Natural Science Foundation of China(21371052)the Scientific Research Fund of Heilongjiang Provincial Education Department(12531512)
文摘Two cobalt coordination polymers with the same 2D structure have been hydrothermally synthesized based on two bifunctional ligands with tetrazole and phosphonate(phosphonic acid) groups,namely,diethyl 4-(2H-1,2,3,4-tetrazol-5-yl) benzylphosphonate(C_2H_5-L1) and 4-(2H-1,2,3,4-tetrazol-5-yl)benzylphosphonic acid(H_2L2). The structures of the two complexes are characterized by elemental analysis,IR,TGA and X-ray single-crystal/powder diffraction. The pink block crystals of complex [Co(L1)(H_2O)]·H_2O(1) belong to the monoclinic system,space group C2/m with a = 20.8390(11),b = 7.2695(3),c = 10.0156(6) A,β = 109.773(7)°,V = 1427.80(13) A^3,Z = 4,D_c = 1.680 mg/cm^-3,M_r = 361.16,F(000) = 740,R = 0.0316 and wR = 0.0826 for 1702 observed reflections(I 〉 2σ(I)). The purple block crystals of complex [Co(L2)(H_2O)]·2H_2O(2) also belong to the monoclinic system,space group C2/c with a = 25.5382(16),b = 7.3844(3),c = 15.1925(11) A,β = 124.238(9)°,V = 2368.6(2) A^3,Z = 8,D_c = 1.969 mg/cm^-3,M_r = 351.12,F(000) = 1432,R = 0.0475,wR = 0.1617 for 2088 observed reflections(I 〉 2σ(I)). Both the nitrogen atoms of tetrazole group and oxygen atoms of phosphonate(phosphonic acid) groups in the ligands coordinated with the metal cobalt. The magnetic property of complex 1 is also investigated.
基金supported by the National Natural Science Foundation of China (22275131)the Institutional Research Fund from Sichuan University (2021SCUNL201)+1 种基金the 111 Project (B20001)the Fundamental Research Funds for the Central Universities。
文摘With the increase of people’s demand,it is extremely desired for developing high-safety,widetemperature-range and high-energy-density lithium batteries,but huge challenges are remained due to shrinkage and combustion of commonly used polyolefin separators at high temperatures,as well as narrow usable temperature range and high flammability of conventionally commercialized liquid electrolytes.In this work,we report a multifunctional separator mainly consisting of Zn^(2+)-phytate coordination complex nanoparticles and bacterial cellulose nanofibers,named the BZP separator,which possesses high porosity,excellent thermotolerance,good flame retardancy,abilities of anion binding and Ni^(2+)capturing.Through cooperating with the fluoride-free wide-temperature-range electrolyte,Li//LiFePO_(4) cells not only deliver discharge capacities of 110.39 mA h g^(-1)and 113.25 mA h g^(-1)after 2200 cycles (2 C) and1600 cycles (5 C) at 25℃,with capacity retentions of 76.59%and 86.09%,respectively,but also exhibit excellent cycling performance at 80℃ and-40℃.Significantly,the Li//NCM811 cell with a loading of7.8 mg cm^(-2)delivers a discharge capacity of 146.64 mA h g^(-1)after 200 cycles at 0.5 C,with a capacity retention of 89.03%.In addition,pouch cells can work at 120℃ and have low flammability.
基金Project supported by the National Natural Science Foundation of China (Grant No 10774103)the Doctoral Education Fund of the Education Ministry of China (Grant No 20050610011)
文摘By simulating the electron paramagnetic resonance (EPR) and optical spectra on the basis of the 120 × 120 complete energy matrix, this paper determines the local lattice structure parameters R1 and R2 for MCl:V2+ (M=Na, K, Rb) systems at 77K, 195 K and RT (room temperature 295 K or 302 K), respectively. The theoretical results indicate that there exists a compressed distortion in MCl:V2+ systems. Meanwhile, it finds that the structure parameters R1, R2 and |△R|( = R1 - R2) increase with the rising temperature. Subsequently, from the analysis it concludes that the relation of EPR parameter D vs. △R is approximately linear. Finally, the effects of orbital reduction factor k on the g factors for the three systems have been discussed.
基金Supported by the Natural Science Foundation of Anhui Province (090416239)the Science and Technology Play (?) Projects of Anhui Province (09020203071)+2 种基金the National Natural Science Foundation of China (20871089)the Foundation of Anhui Provincial Education Department for Outstanding Young Talents in University (2009SQRZ172)the Scientific Research Foundation for the Professors (Doctors) of Suzhou University (2010jb01)
文摘Two new transition metal compounds, [Mn(dpa)2(tmd)2]n (1, H2dpa = 4-hydroxy-phenyl-acetic acid, tmd = 4,4-trimethylenedipyridine) and [Co4(dpa)6(tmd)4(H2O)4]n·nH2O·nCl2 (2), have been synthesized by hydrothermal synthesis. Compound 1 crystallizes in the monoclinic system, space group P21/n with a = 9.828(3), b = 17.493(5), c = 11.616(4), β = 110.146(6)o, V = 1874.9(10)3, C42H42MnN4O6, Mr = 753.74, Z = 2, Dc = 1.335 g/cm3, μ = 0.406 mm-1, F(000) = 790, the final R = 0.1047 and wR = 0.2021 for 2698 observed reflections (I 〉 2σ(I)). Compound 2 crystallizes in the monoclinic system, space group P21/c with a = 11.7214(13), b = 17.1582(19), c = 24.625(3), β = 103.055(3)o, V = 4824.4(9)3, C100H104Cl2Co4N8O23, Mr = 2094.55, Z = 2, Dc = 1.443 g/cm3, μ = 0.809 mm-1, F(000) = 2180, the final R = 0.0550 and wR = 0.0673 for 4104 observed reflections (I 〉 2σ(I)). These complexes were characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. The structural analyses show that the two compounds are both one-dimensional chain structures. However, compounds 1 and 2 form threedimensional supramolecular structures by hydrogen bonds, respectively.
基金Supported by the Key projects of Hubei Provincial Education Department(D20171902)
文摘Two new cobalt(II) coordination complexes, namely [Co(HL)2(biim)(H2O)2]n·n H2O(1) and [Co(Et L)2(biim)]n·3 n(H2O)·2 n(Et HL)(2)(H2L =(fluorene-9,9-diyl)dipropanoic acid, biim = 1,3-bis(imidazol-1-yl)butane), have been synthesized using the same starting reactants but different solvent medium. The two complexes exhibit distinctly different structures. Compound 1 exhibits a one-dimensional linear chain structure. However, complex 2 reveals a one-dimensional zigzag chain structure. Thermogravimetric analyses(TGA) and luminescent properties of these two complexes have been discussed.
基金Supported by the National Natural Science Foundation of China (No.20671064)Doctor Foundation of Liaoning Province (No.20071016)
文摘The 1-D chain coordination complex of {[Mn2(HCAM)3(H2bipy)]·5H2O}n (H3CAM = 4-hydroxypyridine-2,6-dicarboxylic acid, bipy = 4,4'-bipyridine) has been synthesized by the reaction of 4-hydroxypyridine-2,6-dicarboxylic acid, 4,4'-bipyridine and manganese carbonate under hydrothermal conditions, and its crystal structure was determined by X-ray diffraction method The crystal belongs to the monoclinic system, space group P21/n with a = 10.110(2), b = 20.159(4), c = 17.861(4)A,β = 99.67(3)°, V = 3.5884(12) nm3, Mr= 901.47, Z = 4, Dc= 1.669 g.cm^-3, μ= 0.798 mm^-1, F(000) = 1840, the final R = 0.0713 and ωR = 0.1853. The complex forms a 1-D chain bridged by HCAM, protonated 4,4-bipyridines link the 1-D chains to construct 2-D networks via N-H...O hydrogen bonds, and networks are further extended via π-π stacking and hydrogen bonds into 3-D supramolecular framework.
基金supported by the National Natural Science Foundation of China(21373221)the Natural Science Foundation of Fujian Province(2006L2005 and 2014H0007)
文摘A novel coordination complex,{[Cd)2(C(20)H(10)O5)2(H2O)4]·10H2O}n,has been synthesized based on fluorescein(2-(6-hydroxy-3-oxo-3 H-xanthen-9-yl) benzoic acid) and systematically characterized by elemental analysis,infrared(IR) spectrum,thermo gravimetric analysis(TGA),powder X-ray diffraction(PXRD) and single-crystal X-ray diffraction.Compound 1 crystallizes in monoclinic,space group P2/n with a = 20.428(5),b = 8.084(2),c = 21.689(5)A,β = 96.360(5)°,Mr = 993.46,V = 3559.7(15)A^3,Z = 4,Dx = 1.845 g/cm^3,μ = 1.276 mm^-1,F(000) = 1974,GOOF = 1.044,λ(Mo Kα) = 0.71073 ?,the final R = 0.0553 and wR = 0.1720 for 7245 observed reflections with I 〉 2σ(I).
基金Support by National Natural Science Foundation of China(21371052)the Scientific Research Fund of Heilongjiang Provincial Education Department(12531512)
文摘A novel tetrazylphosphonate ligand, namely ethyl 4-(2-ethyl-2H-1,2,3,4-tetrazol-5-yl) benzylphosphonate(Et-L), was designed and successfully achieved from p-cyano benzyl chloride, based on which a zinc coordination polymer(1) with a 2D layer structure has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, TGA and X-ray single-crystal diffraction. The colorless block crystals of H_2L·H_2O were also obtained under the same hydrothermal conditions, which belongs to monoclinic system, space group P2_1/c with a = 13.3141(7), b = 5.1650(3), c = 21.9839(18) A, β = 115.307(5)°, V = 1366.69(15)A3, Z = 4, D_c = 1.391 mg/cm^(-3), Mr = 349.58, F(000) = 600, R = 0.0748 and wR = 0.1917 for 2392 observed reflections(I 〉 2σ(I)). The colorless block crystals of complex 1([Zn(L)(H_2O)]_n) also belong to monoclinic system, space group P2_1/c with a = 22.7464(10), b = 6.0430(3), c = 9.7704(4) ?, β = 92.525(4)°, V = 1341.70(10)A3, Z = 4, D_c = 1.731 mg/cm_(-3), M_r = 349.58, F(000) = 712, R = 0.0596 and wR = 0.1688 for 2357 observed reflections(I 〉 2σ(I)). Only the oxygen atoms of phosphonic group are coordinated with the metal zinc probably because the hydrogen atom of tetrazole has been substituted by ethyl group. Photoluminescence properties of the complex are also investigated.
基金supported by the National Natural Science Foundation of China(22478005,22578006 and 22271002)the Natural Science Foundation of Anhui Province(2308085J14)the Scientific Research Foundation of the Higher Education Institutions of Anhui Province(2022AH051142).
文摘A novel double-stranded trinuclear bis(tridipyrrin)zinc(Ⅱ)complex,constructed from a linearπ-conjugated tridipyrrin ligand,was synthesized and characterized.The complex featuring six directly linked dipyrrin units exhibits a stable double-helical structure with two non-superimposable P and M enantiomers,as confirmed by X-ray crystallography.Chirality was further demonstrated through HPLC separation and mirror-image circular dichroism(CD)spectra.The complex shows strong near-infrared(NIR)absorption and excellent solubility in various solvents,attributed to its sterically hindered structure.Spectroscopic,electrochemical,and theoretical studies revealed its unique electronic properties and redox behavior.This work advances the design of chiral NIR-active metallo-supramolecular systems and highlights potential applications in chiroptical mateials.
文摘An unusual inorganic-organic hybrid hexatungstate complex [Cu(phen)3][W6O19] 1 (C36H24 CuN6O19W6, Mr= 2011.20) was hydrothermally synthesized and characterized by singlecrystal X-ray diffraction, IR spectrum, UV-VIS spectrum and elemental analyses. This compound crystallizes in the monoclinic system, space group C2/c with a = 19.1005(11), b = 11.2585(11), c = 20.2867(15) A, β= 102.177(2)°, V= 4264.4 A^ 3, μ(MoKa) = 16.691 mm^-1, Dc = 3.133 g/cm^3, Z = 4, F(000) = 3628, the final R = 0.0338 and wR = 0.0798 for 4090 observed reflections with I 〉 2σ(I). The result of structure determination shows that the crystal structure is constructed from [W6O19]^2- cluster anions and [Cu(phen)3]^2+ complex fragments, which are held together into a three-dimensional network through hydrogen-bonding interactions.
文摘This work reports a feasible synthesis of highly-dispersed Pt and Pt-Fe nanoparticles supported on multiwall carbon nanotubes (MWCNTs) without Fe and multiwall carbon nanotubes with iron (MWCNTs-Fe) which applied as electrocatalysts for methanol electrooxidation. A Pt coordination complex salt was synthesized in an aqueous solution and it was used as precursor to prepare Pt/MWCNTs, Pt/MWCNTs-Fe, and Pt-Fe/MWCNTs using FeC12.4H20 as iron source which were named S 1, S2 and S3, respectively. The coordination complex of platinum (TOA)2PtC16 was obtained by the chemical reaction between (NH4)2PtC16 with tetraoctylammonium bromide (TOAB) and it was characterized by FT-IR and TGA. The materials were characterized by Raman spectroscopy, SEM, EDS, XRD, TEM and TGA. The electrocatalytic activity of Pt-based supported on MWCNTs in the methanol oxidation was investigated by cyclic voltammetry (CV) and chronoamperometry (CA). Pt-Fe/MWCNTs electrocatalysts showed the highest electrocatalytic activity and stability among the tested electrocatalysts due to that the addition of "Fe" promotes the OH species adsorption on the electrocatalyst surface at low potentials, thus, enhancing the activity toward the methanol oxidation reaction (MOR).
基金supported by the National Natural Science Foundation of China (No. 21407021)the Shanghai Yang-Fan Program of Science and Technology Commission of Shanghai (No. 14YF1405000)+1 种基金the National Key Research and Development Program of China (No. 2016YFC0400501)the Fundamental Research Funds for the Central Universities and DHU Distinguished Young Professor Program
文摘Chitosan–metal complexes have been widely studied in wastewater treatment, but there are still various factors in complex preparation which are collectively responsible for improving the adsorption capacity need to be further studied. Thus, this study investigates the factors affecting the adsorption ability of chitosan–metal complex adsorbents, including various kinds of metal centers, different metal salts and crosslinking degree. The results show that the chitosan–Fe( Ⅲ) complex prepared by sulfate salts exhibited the best adsorption efficiency(100%) for various dyes in very short time duration(10 min), and its maximum adsorption capacity achieved 349.22 mg/g. The anion of the metal salt which was used in preparation played an important role to enhance the adsorption ability of chitosan–metal complex. SO4^(2-) ions not only had the effect of crosslinking through electrostatic interaction with amine group of chitosan polymer, but also could facilitate the chelation of metal ions with chitosan polymer during the synthesis process.Additionally, the p H sensitivity and the sensitivity of ionic environment for chitosan–metal complex were analyzed. We hope that these factors affecting the adsorption of the chitosan–metal complex can help not only in optimizing its use but also in designing new chitosan–metal based complexes.