Leaching of low grade zinc oxide ores in Ida^(2-)-H_2O system

Ida2--H2O system（iminodiacetate aqueous solution） was used to leach a low grade zinc oxide ore for Zn extraction.The effects of leaching time,liquid-solid ratio（L/S）,total concentration of Ida2-（[Ida2-]T）,leaching temperature and pH on Zn leaching recovery and the dissolution of impurities such as Ca,Mg,Cu,Ni,Fe,Pb and Cd were investigated.Results show that Ca,Mg and Fe in ores were hardly dissolved in alkalescent iminodiacetate aqueous solution,while valuable metals such as Cu,Ni,Pb and Cd were partly dissolved into leaching liquor with Zn.The recovery of Zn reaches 76.6% when the ores were leached for 4 h at 70 ℃ by 0.9 mol/L iminodiacetate aqueous solution with pH of 8 and L/S of 5：1.

Construction of a New(4,8)-Connected Coordination Polymer Based on the Zinc Cluster:Structure,Topology,and Luminescence

The title complex, [Zn3（L）2（H2 O）2]n（1, H3 L = 5-（（3-formylphenoxy）methyl）isophthalic acid）, has been synthesized under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction, IR spectroscopy and thermogravimetric analysis. Compound 1 exhibits a 3D binodal（4,8）-connected net based on trinuclear [Zn3（COO）4] clusters with the topology symbol of（416·612）（44·62）2. It crystallizes in monoclinic system, space group P21/c, with a = 13.548（3）, b = 13.291（3）, c = 8.2750（1） ？, β = 97.08（3）°, V = 1478.7（6） ？3, Z = 2, Mr = 858.6 g/mol, Dc = 1.928 mg/m3, μ = 2.49 mm-1, F（000） = 864, GOOF = 1.12, the final R = 0.0457 and wR = 0.1329 for 4334 observed reflections with I 〉 2σ（I）. Additionally, the photoluminescent behaviours of 1 and H3 L have also been investigated in the solid state at room temperature.

Synthesis,Crystal Structure and Properties of a Zinc(Ⅱ) Complex Based on 5-(1H-Tetrazol-5-yl)isophthalic Acid Ligand

A novel polymeric zinc（II） complex {[Zn2（TIA）（H2O）3]·（NO3）}n（1, H3TIA = 5-（1H-tetrazol-5-yl）isophthalic acid） has been synthesized in mixed solvents under solvothermal conditions and characterized by elemental analysis, IR spectroscopy and X-ray single-crystal diffraction. Complex 1 crystallizes in orthorhombic, space group Cmcm with a = 10.4210（6）, b =23.3526（14）, c = 6.9214（4）A, V = 1684.37（17）A^3, Z = 4, C9H4N5O（10）Zn2, Mr = 472.91, Dc = 1.865g/cm^3, F（000） = 932, λ（MoK α） = 2.909 mm^-1, R = 0.0423 and wR = 0.1287. The complex has good thermal stability and excellent photoluminescent property.

Synthesis,Structure and Photoluminescence of Cocrystal of Bis[2-(benz(oxa/imida)zol-2-yl)phenolato-к~2N,O]zinc(Ⅱ) Being Site Occupancy Disorder with a Heteroatom Ratio of NH to O(0.408/0.592)

The zinc（Ⅱ） complex with Hpbx （Hpbx = 2-（benzoxazol-2-yl）phenol） and Hpbm （Hpbm = 2-（benzimidazol-2-yl）phenol）, namely [Zn（pbm）2]1.633[Zn（pbx）212.367·DMF·2H2O 1, has been synthesized and characterized by X-ray crystallography, FTIR and elemental analysis. The coordination structures are statistically disordered and can be regarded as a co-crystal of [Zn（pbm）2] and [Zn（pbx）2] with the ratio of ca. 0.408/0.592. Solvate water and DMF molecules are also present in the lattice. Crystal data for 1; monoclinic, space group P21/c, Mr= 2049.02, Z = 2, α = 9.7571（6）, b = 25.6415（16）, c = 19.8675（10） A, β= 111.342（2）°, V = 4629.7（5） A^3, Dc = 1.470 g/cm^3,μ = 1.100 mm^-1, F（000） = 2104, R = 0.0575 and wR = 0.1282 for 5528 observed reflections （I〉2σ（I））. The photoluminescent spectra for this compound have also been studied.

Syntheses,Structures,and Luminescent Properties of Zinc(Ⅱ)and Silver(Ⅰ)Complexes Based on 1-(4′-Carboxylatobenzyl)-3-(pyrazin-2-yl)pyrazole

Two novel coordination compounds, [Zn（CBPP）2（H2O）2]·3H2O（1） and[Ag（CBPP）·2H2O]（2）（HCBPP = 1-（4？-carboxylatobenzyl）-3-（pyrazin-2-yl）pyrazole）, were hydrothermally synthesized and characterized. Compound 1 crystallizes in monoclinic, space group C2 with a = 26.221（4）, b = 8.4211（7）, c = 14.295（3）A, β = 114.561（8）°, V = 2705.9（2） A3, Dc = 1.587 g/cm3, C28H28Cl2N8O9 Zn, Mr = 685.97 F（000） = 1416, μ（Mo Kα） = 0.926 mm-1, Z = 4, R = 0.0287, w R = 0.1076 for 2818 observed reflections（I 〉 2σ（I））, and R = 0.0300, w R = 0.1110 for all data. In 1, each deprotonated CBPP-ligand with a bidentate coordination mode connects two Zn（II） atoms to generate a 1D helical chain along the b axis. The adjacent chains intersect with each other through hinged Zn（II） ions to build up an interesting two-dimensional network. Compound 2 crystallizes in monoclinic, space group P21/n with a = 6.3544（1）, b = 11.7195（3）, c = 19.3188（4）A, β = 94.297（2）°, V = 1434.64（5） A3, Dc = 1.894 g/cm3, C14H13 Ag N4O4, Mr = 409.15 F（000） = 816, μ（Mo Kα） = 11.536 mm-1, Z = 4, R = 0.0456 and w R = 0.1184 for 2402 observed reflections（I 〉 2σ（I））, and R = 0.0517, w R = 0.1275 for all data. In 2, each ligand binds two Ag（I） atoms in a tridentate coordination mode to form an infinite zigzag chain. Their thermal and photoluminescent properties were also investigated.

Synthesis, Structure and Geometrical Calculation of a Novel Co-crystal of {[4-Bromo-2-(benzimidazol-2-yl)phenolato][2-(1-butylbenzimidazol-2-yl)phenolato]zinc(Ⅱ)] and Bis[μ-2-(1-butylbenzimidazol-2-yl)phenolato]-1κN^3:2κO;1κO:2κN^3-bis{[2-(1-butylbe

The title compound has been synthesized and characterized crystallographicaUy. It is a co-crystal consisting of two different neutral zinc（H） complexes with Hbpbm （Hbpbm = 4- bromo-2-（benzimidazol-2-yl）phenol） and Hnpbm （Hnpbm = 2-（1-butylbenzimidazol-2-yl）phenol）. One is a monomeric mixed-ligand complex of [Zn（bpbm）（npbm）] 1 and the other a dimer of [Zn2（npbm）4] 2 with their ratio of 2：1. Thus the overall formula for the title compound is 21.2. Adjacent 1 and 2 are connected to each other by intermolecular hydrogen bonding interactions in the lattice. The crystal data： monoclinic, space group P21/c, a = 15.0141（12）, b = 20.9941（17）, c = 18.4686（15） A, β = 97.445（2）°, V = 5772.4（8） A^3, Mr= 2429.68, Z = 2, Dc = 1.398 g/cm^3,μ = 1.579 -1 mm , F（000） = 2504, R = 0.0637 and wR = 0.1771 for 6464 observed reflections （I 〉 2σ（I））. The geometrical structure for 1 has also been theoretically optimized and compared with the experimental one.

Synthesis and Crystal Structure of 3,3'-Bis(2-benzimidazolyl)-2,2'-dipyridine with Hydrated Zinc(Ⅱ) Perchlorate

The reaction of Zn（ClO4）2·6H2O with 3,3＇-bis（2-benzimidazolyl）-2,2＇-dipyridine （L） gave a mononuclear zinc（Ⅱ） complex： [ZnL2]（CIO4）2·2DMF·4H2O, which was structurally characterized by EA, IR, UV, ^1H NMR, fluorescence spectrum and single-crystal X-ray diffraction. The crystal （C54H54Cl2N14O14Zn, Mr = 1259.38） belongs to the monoclinic system, space group C2/c with a = 20.874（2）, b = 14.9953（16）, c = 20.462（3）A,β= 101.553（2）°, V= 6274.8（13） A, Z= 4, Dc= 1.333 g/cm^3, F （000） = 2608,/a（MoKcr） = 0.548 mm 1, R = 0.0682 and wR = 0.1931 for 4984 observed reflections with I 〉 2σ（I）. The Zn（Ⅱ） is four-coordinated in a slightly distorted tetrahedral geometry through four N atoms from four benzimidazole units of two ligands. In the crystal lattice, the [ZnL2]2^＋ cations are linked to each other by extensive intermolecular hydrogen bonds between nitrogen atoms of benzimidazole rings, water and DMF molecules.

An aqueous BiI_(3)-Zn battery with dual mechanisms of Zn^(2+)(de)intercalation and I^(-)/I_(2)redox

The development of aqueous battery with dual mechanisms is now arousing more and more interest.The dual mechanisms of Zn^(2+)(de)intercalation and I^(-)/I_(2)redox bring unexpected effects.Herein,differing from previous studies using Zn I_(2)additive,this work designs an aqueous Bi I_(3)-Zn battery with selfsupplied I^(-).Ex situ tests reveal the conversion of Bi I_(3)into Bi(discharge)and Bi OI(charge)at the 1st cycle and the dissolved I^(-)in electrolyte.The active I^(-)species enhances the specific capacity and discharge medium voltage of electrode as well as improves the generation of Zn dendrite and by-product.Furthermore,the porous hard carbon is introduced to enhance the electronic/ionic conductivity and adsorb iodine species,proven by experimental and theoretical studies.Accordingly,the well-designed Bi I_(3)-Zn battery delivers a high reversible capacity of 182 m A h g^(-1)at 0.2 A g^(-1),an excellent rate capability with 88 m A h g^(-1)at 10 A g^(-1),and an impressive cyclability with 63%capacity retention over 20 K cycles at 10 A g^(-1).An excellent electrochemical performance is obtained even at a high mass loading of 6 mg cm^(-2).Moreover,a flexible quasi-solid-state Bi I_(3)-Zn battery exhibits satisfactory battery performances.This work provides a new idea for designing high-performance aqueous battery with dual mechanisms.

Synthesis, Crystal Structure and Properties of a New Zn(II) Coordination Polymer Constructed from 2,3-Pyridine Dicarboxylic Acid and 1,1′-(1,4-Butanediyl)bis(imidazole)

A new coordination polymer, namely [Zn（pdc）（bbi）]n {H2 pdc = 2,3-pyridine dicar- boxylic acid, bbi = 1,1-（1,4-butanediyl）bis（imidazole）}, has been prepared under hydrothermal conditions and characterized by elemental analysis, IR, and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group P21 /n with a = 8.436（3）, b = 16.988（5）, c = 12.106（4）, β = 92.204（5）°, V = 1733.6（9）3, Z = 4, C17 H17 N5 O4 Zn, Mr = 420.73, Dc = 1.612 g/cm3, F（000） = 864, μ（MoKa） = 0.452 mm-1, the R = 0.0672 and wR = 0.1645. In the mononuclear complex, each Zn（II） is five-coordinated by one carboxylate O and one pyridyl N atoms from one pdc anion, one carboxylate O atom from another pdc anion, and two N atoms from two bib ligands. The Zn（II） ions are connected by pdc ligands to form skeleton chains, and bbi ligands further link them to construct a 2D framework. The thermal and luminescence properties of the complex were also investigated.

A Two-dimensional Metallic Oxide Constructed from Molybdenum Clusters and Zn(Ⅱ)-[3-(2-pyridyl)pyrazole] Cationic Coordination Components

A new polyoxomolybdate compound [Zn（HL）2（Mo8O26）（4,4＇-Bipy）]·（4,4＇-Bipy） （HL = 3-（2-pyridyl）pyrazole, 4,4＇-Bipy = 4,4＇-bipyridine） 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses, TG and IR spectroscopy. The compound crystallizes in monoclinic, space group C2/c with a = 18.060（4）, b = 13.870（3）, c = 19.360（4） A, β = 93.50（3）°, V = 4840.5（17） 3, C36H30Mo8N10O26Zn, Mr = 1851.59, Dc = 2.541 g/cm^3, μ（MoKα） = 2.589 mm·1, F（000） = 3560, Z = 4, the final R = 0.0328 and wR = 0.0870 for 4005 observed reflections （I 〉 2σ（I））. X-ray diffraction analyses reveal that compound 1 is constructed from Mo8O264-units linked by Zn（HL）22＋ and 4,4＇-Bipy. Mo8O264-is connected by Zn（HL）2^2＋ via terminal oxygen atoms along the [010] axis forming chains, which are further linked by 4,4＇-Bipy along the [001] axis forming a two-dimensional network structure.

A New Zn(Ⅱ) Coordination Polymer Constructed from 4-(1H-pyrazol-3-yl)pyridine as Fluorescent Sensor for Fe^(3+)

A new Zn(Ⅱ) coordination polymer, [Zn(4-PP)(1,4-BDC)?(H_2O)]_n(1, 4-PP = 4-(1 H-pyrazol-3-yl)pyridine, 1,4-H_2BDC = 1,4-benzenedicarboxylic acid), has been synthesized and structurally characterized by single-crystal X-ray diffraction as well as elemental analysis, IR spectra, XRPD and TG. Structural analysis reveals that Zn(Ⅱ) ions are bridged by COO-from 1,4-BDC^(2-)to form a binuclear structure as the second building units(SBUs). Zn_2 clusters can be clarified as 4-connected nodes, so the framework of 1 can be considered as a 2 D(44?62)-sql sheet. Fluorescence measurements show that 1 has highly selective and sensitive detection of Fe^(3+) in water medium.

A Zn(Ⅱ) Coordination Polymer Based on a Flexible Polycarboxylate Ligand 5-(4-Hydroxypyridinium-1-ylmethyl)-isophthalic Acid: Synthesis, Structure, and Property

A Zn（Ⅱ） supramolecular coordination polymer, {[Zn2（L）2（m-bix）（H20）]6H2O}n（1）, with an interesting 1D→2D polythreading array from a flexible and angular organic aromaticpolycarboxylate ligand 5-（4-hydroxypyridinium-l-ylmethyl）isophthalic acid （H2L）, and N-donorligand 1,3-bis（imidazol-l-ylmethyl）benzene （m-bix）, has been obtained under hydrothermalconditions and characterized by elemental analysis, powder X-ray diffraction （PXRD）, IR, thermalgravimetric analyses （TGA） and single-crystal X-ray diffraction. In 1, the Zn（Ⅱ） center has twocoordination geometries. One exhibits a trigonal bipyramidal coordination sphere, and the other isa tetrahedral geometry; L2- has two different coordination modes, with one connecting three Zn（Ⅱ）ions through two monodentate carboxylate groups and the monodentate hydroxyl group, and theother bridging two Zn（Ⅱ） ions through two carboxylate groups. The L2- anions connect the Zn（Ⅱ）centers forming an infinite 1D tubular structure. These 1D tubes are interconnected by the m-bixspacers to form a 2D framework. Such 2D layers are further assembled into a 3D supramolecularnetwork via hydrogen bonds. Meanwhile, the luminescent property of 1 has also been investigatedin detail.

Synthesis,Structure,and Surface Photo-electric Properties of a New Zn(Ⅱ)Coordination Complex Constructed from 2-(1H-benzotriazol-1-yl)acetic Acid and 1,10-Phenanthroline Ligands

A new binuclear Zn^Ⅱ coordination complex,Zn2（bta）（phen）2（Cl）3（1,Hbta = 2-（1Hbenzotriazol-1-yl）acetic acid and phen = 1,10-phenanthroline）,has been synthesized and characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental,and photoluminescent analysis.Complex 1 crystallizes in triclinic system,space group P1 with a = 9.3040（19）,b = 10.694（2）,c =16.841（3） A°,α = 101.18（3）,β = 105.77（3）,γ = 91.72（3）°,V= 1575.8（5） A°3,C（32）H（22）Zn2Cl3N7O2,Mr =773.66,Dc = 1.631 g/cm^3,Z = 2,F（000） = 780,μ = 1.820 mm^-1,the final R = 0.1238 and wR =0.1131.X-ray diffraction analyses indicate that 1 displays two crystallographic independent Zn^Ⅱmetal centers with a distorted tetragonal pyramidal（ZnN4O） and a tetrahedral（ZnNCl3） geometries,respectively.The phen serves as a common N,N＇-bidentate ligand,and the bta^- as a unique N,O-bridged ligand in 1.In the crystal,1 forms a stable 3D supramolecular architecture by trifurcated hydrogen bonding C-H…C1 interactions and C-H…π,π…π stacking.1 showed photo-electric conversion properties.

Effect of ZnO on Oxidation Resistance of Low Carbon MgO-C Refractories

Al-containing low carbon MgO - C refractories were prepared using 70% （in mass, the same hereinafter） fused magnesia （ ≤3 mm）, 24% fused magnesia powder （ 〈0. 074 mm） , 3% flake graphite, 3% Al powder and 4% phenolic resin （extra-added） as the basic formulation. Influence of ZnO addhion on oxidation resistance of the materials was investigated by adding 1% ZnO to substitute fused magnesia powder. The relationship between in-situ formed spinel and ZnO in the matrix was discussed by comparing apparent porosity, cold crushing strength, and phase evolution of the materials matrix. The oxidation resistances of the two materials were compared by observing the formed dense MgO layer between the decarburized layer and the original layer. The result shows that adding ZnO in MgO - C refractories accelerates the in-situ formation of ZnAl204 spinel and the formation of dense MgO layer, thus improves the oxidation resistance of the low carbon MgO - C refractories.

Synthesis and Crystal Structure of [Zn(FcCOO)_2(2,2'-bipy)(H_2O)]_2·H_2O

A novel complex [Zn（FcCOO）2（2,2＇-bipy）（H2O）]2-H2O （Fc = （η^5-C5H5）Fe（η^5-CsH4）, 2,2＇-bipy = 2,2＇-bipyridine） has been synthesized and characterized by elemental analysis, IR and X-ray diffraction. It crystallizes in monoclinic system, space group P21/c with a = 6.8187（4）, b = 21.7155（13）, c = 19.7411（12） A, a = 90, β = 97.7420（10）, γ = 90°, CtaHssFe4Zn2N4O11, Mr = 1413.28, V = 2896.4（3）A^3, Dc = 1.620 g/cm^3, Z = 2, F（000） = 1444,μ（MoKa） = 1.857 mm^-1, R = 0.0523 and wR = 0.0982 for 3219 observed reflections （I 〉 2σ（I））. Structural analysis shows that the zinc atom is coordinated with three oxygen atoms from two ferrocenemonocarboxylates and one water molecule together with two nitrogen atoms from 2,2＇-bipyridine, giving a distorted square-pyramidal coordination geometry. The complex molecules are linked to form an infinite one-dimensional chain by both intermolecular hydrogen bonds and π-π stacking interactions of the bipyridine rings.

Study on Capacitance of Zn-Based Electrode in Redox Electrolyte System

Electrode material is one of the most important factors affecting the performance of supercapacitors, and electrolyte solution is another. In this work, electrochemical properties of hydroxide zinc carbonate composite electrode (HZC) in KOH + K3[Fe(CN)6] electrolyte were studied. It was proved that [Fe(CN)6]3−in electrolyte participated in electrochemical reactions and promoted electron transfer. The specific capacitance of HZC electrode was as high as 920.5 F·g−1 at 1.0 A·g−1 in 1 mol·L−1 KOH and 0.04 mol·L−1 K3[Fe(CN)6] electrolyte, which is 172.9% higher than that in KOH. The combination of HZC electrode and low alkalinity aqueous electrolyte provided the supercapacitor system with good capacitance performance, safety, and environmentally friendly.

毛坪铅锌矿矿山地质环境质量的模糊评判

矿山地质环境质量评价是一项复杂的系统工作,由于影响因素较多,难以用统一的标准进行度量,至今仍未形成一套标准的评价方法。选取影响矿山地质环境的岩石类型、断层密度、沟床纵坡降、节理发育程度、汇水面积、崩塌体积、地面沉降、地下水位下降、水土流失、矿坑口数量、采矿区面积、雨季降雨量、植被覆盖率等23个因素作为评价因子,应用模糊评价的原理与方法,通过建立模糊数学模型和隶属度矩阵,将毛坪铅锌矿矿山地质环境质量划分为好、较好、较差及差4个等级,评价结果为毛坪铅锌矿矿山地质环境保护和整治规划提供了依据。

Synthesis of zinc-based metal-organic framework as highly efficient photocatalyst for decomposition of organic dyes in aqueous solution

In the present work,a zinc-based metal-organic framework{[Zn(ddpd)_(0.5)(bipy)_(0.5)]·H_(2)O]}_(n)(1-Zn)(where ddpd=2,5-di(2',4'-dic arboxylphenyl)-1,4-difluorobenzene,bipy=4,4-bipyridine)was synthesized by a solvothermal method.Complex 1-Zn features a threedimensional(2,4,6)-connected network with{4^2.6^2.8^2}_(2){4^4.6^6.8^5}{6}topology.Meanwhile,without the assistance of other reagents,complex 1-Zn not only exhibited an exceeded 95%photodegradation efficiency for rhodamine B(Rh B),methyl blue(MB)and methyl orange(MO)within 40 min,but also showed high stability and recyclability.In addition,free radical quenching experiments and electron spin resonance(ESR)spectroscopy verified that the main active species in the photodegradation process were·O_(2)^(-)and OH,and a more indepth degradation mechanism was further elucidated by density functional theory(DFT)calculations.

Synergistic extraction of zinc from ammoniacal solutions using a β-diketone mixed with trialkylphosphine oxide

A simple comparative study of synergistic extraction of zinc from ammonium sulfate and ammonium chloride systems with mixtures of Mextral54-100 and tri-nalkylphosphine oxide(TRPO) dissolved in n-heptane was described. Various parameters affecting the extraction process were investigated. Experimental results show that extraction from ammonium sulfate is better than that from ammonium chloride under the same conditions owing to the additional complexation between zinc and chloride ions. Total ammonium concentration and pH have a significant effect on zinc extraction efficiency because of the formation of zinc ammine complexes. The synergistic effect is explained by the formation of adduct between zinc chelates and trialkylphosphine oxide. The thermodynamic data show that the extraction reaction is exothermic and stripping is endothermic. Infrared(IR) spectra of the zincloaded organic phases were also examined.

Syntheses,Structures,and Photoluminescent Properties of Two Zn(Ⅱ)Coordination Polymers with Helical Chains Structures

Two novel coordination polymers with helical chains, {[Zn（L）（H2O）]·H2O}n（1） and {[Zn（L）（p-bix）]·3.5H2O}n（2）, where H2 L = 5-（4-hydroxypyridinium-1-ylmethyl） isophthalic acid and p-bix = 1,4-bis（imidazol-1-ylmethyl）benzene, have been hydrothermally synthesized, and charac-terized by elemental analysis, powder X-ray diffraction（PXRD）, IR, thermal gravimetric analyses（TGA） and also by single-crystal X-ray diffraction. Both complexes 1 and 2 crystallize inmonoclinic, space group P21/c. Compound 1 displays a two-dimensional（2D） structure with two distinct types of helical chains; 2 shows a layered coordination polymer with two types of helical chains and features an interesting 2D→3D interdigitated architecture. Meanwhile, the luminescent properties of 1 and 2 have also been investigated in detail.