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Design and Synthesis of Bis-β-ketoimine Binuclear Titanium Complex Isomers to Probe Bimetallic Synergistic Effect for Ethylene Polymerization
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作者 Ming Zhou Meng-Yuan Xue +3 位作者 Ping-Zhou Huang Ting-Cheng Li Qing-Liang You Guang-Yong Xie 《Chinese Journal of Polymer Science》 2025年第5期756-768,共13页
Binuclear complexes have attracted extensive attention in fields such as catalysis because of their likely bimetallic synergistic effect;however,the mechanism and factors influencing this synergism remain unclear.In t... Binuclear complexes have attracted extensive attention in fields such as catalysis because of their likely bimetallic synergistic effect;however,the mechanism and factors influencing this synergism remain unclear.In this work,six bis-β-ketoimine binuclear titanium complexes4a-4f containing different alkylthio sidearms and configurations were synthesized and characterized by nuclear magnetic resonance hydrogen spectrum(~1H-NMR),nuclear magnetic resonance carbon spectrum(^(13)C-NMR),Fourier transform infrared spectrum(FTIR),and elemental analysis.The intermetallic distances of isomeric complexes 4a,4d,4e and 4f determined through density functional theory(DFT)optimization were in the order 4a<4d<4e<4f and were found to significantly influence the catalytic performance for ethylene(co)polymerization.These complexes could efficiently catalyze ethylene polymerization and ethylene/1-hexene or ethylene/1-octene copolymerization with high activity to produce highmolecular-weight ethylene homo-and co-polymers.Among the three binuclear titanium complexes 4a-4c with similar structures but different lengths of alkylthio sidearms,complex 4a,which contained the shortest methylthio sidearm,exhibited the highest activity for ethylene polymerization and copolymerization with 1-hexene or 1-octene.Additionally,for ethylene/1-hexene or ethylene/1-octene copolymerization,it showed the highest comonomer incorporation compared with propylthio(4b)and octylthio(4c)derivatives because of the smaller steric hindrance of the methyl group in 4a and the more open coordination space for vinyl monomers.Furthermore,among the isomeric complexes 4a,4d,4e and4f,complex 4a with the shortest bimetallic distance also exhibited the highest activity towards ethylene(co)polymerization,and the highest 1-hexene or 1-octene incorporation in comparison with its regioisomeric counterparts 4d,4e and p-phenyl-bridged analog 4f,owing to a more appropriate bimetallic distance that is conducive to a synergistic effect. 展开更多
关键词 binuclear titanium complex ISOMER Ethylene polymerization COPOLYMERIZATION Synergistic effect
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Synthesis,crystal structure,and DNA‑binding of binuclear lanthanide complexes based on a multidentate Schiff base ligand
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作者 GUAN Xiaofen LIU Yating +5 位作者 LI Jia HU Yiwen DING Haiyuan SHI Yuanjing WANG Zhiqiang WANG Wenmin 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第12期2486-2496,共11页
Two new dinuclear lanthanidecomplexes,namely[Ln_(2)(dbm)_(2)(HL)_(2)(CH_(3)OH)_(2)]·4CH_(3)OH[Ln=Tb(1)and Dy(2),Hdbm=dibenzoylmethane]have been synthesized using prepared multidentate Schiff base ligand H_(3)L(hy... Two new dinuclear lanthanidecomplexes,namely[Ln_(2)(dbm)_(2)(HL)_(2)(CH_(3)OH)_(2)]·4CH_(3)OH[Ln=Tb(1)and Dy(2),Hdbm=dibenzoylmethane]have been synthesized using prepared multidentate Schiff base ligand H_(3)L(hydroxy‑acetic acid(4‑diethylamino‑2‑hydroxy‑benzylidene)‑hydrazide)with good biological activity.Structure characterizations show that the complex comprises two Ln3+ions,two dbm-ions,two HL^(2-)ligands,two CH_(3)OH molecules,and four free methanol molecules.Each Ln^(3+)ion is eight‑coordinated.The two central Lnions are bridged by twoμ_(2)‑O atoms leading to a parallelogram[Ln2O2]core.The interaction between the compounds(H_(3)L,1,and 2)and the calf thymus DNA(CT‑DNA)has been further confirmed by UV‑Vis spectrometry,fluorescence titration,and cyclic voltammetry.The results showed that both 1 and 2 could undergo insertion with CT‑DNA.CCDC:2343005,1;2343006,2. 展开更多
关键词 binuclear lanthanide complexes crystal structures multidentate Schiff base DNA INSERTION
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柔性桥联双核卟啉铝催化二氧化碳/环氧化物交替共聚反应
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作者 范培鑫 刘顺杰 +4 位作者 张若禹 杨列航 高凤翔 陈学思 王献红 《高分子学报》 北大核心 2025年第1期47-57,共11页
受天然酶启发,协同作用被广泛应用于小分子的识别及其催化转化,但在聚合物合成领域的研究仍然有限.本文报道了一种柔性桥联双核卟啉铝催化剂(FTBC),成功实现了CO_(2)与环氧丙烷(PO)的高效交替共聚.该策略的关键在于通过调控柔性链的长... 受天然酶启发,协同作用被广泛应用于小分子的识别及其催化转化,但在聚合物合成领域的研究仍然有限.本文报道了一种柔性桥联双核卟啉铝催化剂(FTBC),成功实现了CO_(2)与环氧丙烷(PO)的高效交替共聚.该策略的关键在于通过调控柔性链的长度使得活性位点相互靠近,从而促进分子内协同作用.受益于活性位点的协同效应,以―CH_(2)―为柔性链的C_(1)-Al_(2)表现出优异的催化活性(380 h^(−1))及较高的聚合物选择性(96%),优于相同条件下的单分子卟啉铝(活性为300 h^(−1),聚合物选择性为78%).即使在低催化剂浓度下,C_(1)-Al_(2)也能保持较好催化活性(250 h^(−1)).动力学实验表明C_(1)-Al_(2)反应级数为一级,证实催化剂的分子内协同催化主导共聚过程.本文报道了一种柔性桥联双核催化剂的构筑策略,为模块化设计高性能催化剂提供了新方向. 展开更多
关键词 双核催化剂 铝卟啉 协同催化 二氧化碳 环氧化物
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Effects of binuclear copper(Ⅱ)threonine complex on blood glucose, lipids and protection of the hearts and kidneys in diabetic mice 被引量:1
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作者 谢英 王菲 +2 位作者 李菲菲 李明升 邓丽丽 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第1期14-17,共4页
Aim To study the effects of binuclear copper (Ⅱ) threonine complex (Cu2 (Thr)4) as analogue of superoxide dismutase (SOD) on blood glucose, blood lipids and vessels of hearts and kidneys in diabetic mice. Met... Aim To study the effects of binuclear copper (Ⅱ) threonine complex (Cu2 (Thr)4) as analogue of superoxide dismutase (SOD) on blood glucose, blood lipids and vessels of hearts and kidneys in diabetic mice. Methods Diabetic mouse model was established by intraperitioneal injection of alloxan. Low, middle, and high doses of Cu2(Thr)4 at 0.002%, 0.02% and 0.1% were given respectively to diabetic mice following lavage. The fasting blood glucose was determined after the diabetic mice were given Cu2 (Thr)4 for 0, 30, and 45 d. The diabetic mice were killed on the 45th day. Then glycosylated hemoglobin (HbAlc) and blood lipids were assayed, and pathologic changes in hearts and kidneys stained with HE were observed. Results Compared with the control group in which the diabetic mice were given distilled water, the value of blood glucose reduced significantly in middle dose group (P 〈 0.01 ), followed by that in low dose group (P 〈 0.05). TC level reduced markedly and HDL level increased significantly in all three treatment groups (P 〈 0.05). Especially in middle dose group, cardiac muscle fibers were neatly arranged, nucleus and cytoplasm well distributed, glomeruli showing normal structure, cells well distributed and staining being normal. Conclusion Cu2 (Thr)4 reduces blood glucose, regulates blood lipids, and play protective action on the vessels of hearts and kidneys in diabetic mice. The effects of it in middle dose were better than those of other doses. 展开更多
关键词 binuclear copper (Ⅱ) threonine complex Diabetic mice Blood glucose Blood lipids
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分子构型对微生物胞外聚合物γ-聚谷氨酸絮凝Zn2+的作用
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作者 蔡星语 刘亚敏 +3 位作者 谢小保 施庆珊 王玲玲 王进 《环境科学学报》 北大核心 2025年第1期50-59,共10页
微生物分泌的胞外聚合物(EPS)与重金属的结合在微生物生存、废水处理和生物修复等方面起到重要作用.然而,EPS的分子结构特征以及这些特征与EPS-重金属络合物的“溶液-絮体”转变过程和机制之间的关系尚不清楚.本研究对微生物胞外聚合物... 微生物分泌的胞外聚合物(EPS)与重金属的结合在微生物生存、废水处理和生物修复等方面起到重要作用.然而,EPS的分子结构特征以及这些特征与EPS-重金属络合物的“溶液-絮体”转变过程和机制之间的关系尚不清楚.本研究对微生物胞外聚合物γ-聚谷氨酸(γ-PGA)与Zn^(2+)形成溶解状态络合物γ-PGA-Zn的二级结构含量、吸附量、Zeta电势、化学键合方式进行了表征,并结合Zn^(2+)和Pb^(2+)共存状态下γ-PGA-重金属离子(γ-PGA-M)的“溶液-絮体”转变过程,明确了分子构型变化在絮凝机制中的重要作用.本文将γ-PGA的絮凝机理扩展到了分子构型水平,为理解γ-PGA在微生物生存、废水处理、生物修复等方面发挥的重要作用提供理论依据,并为γ-PGA及其衍生物、产γ-PGA微生物应用于重金属离子去除和生物修复提供理论指导. 展开更多
关键词 微生物胞外聚合物 Γ-聚谷氨酸 分子构型 双核双齿化学键合
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Structure and magnetic properties of Mn(Ⅱ)coordination polymers regulated by N-auxiliary ligands
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作者 LIU Xiaxia MA Xiaofang +2 位作者 GUO Luxia HAN Xianda FENG Sisi 《无机化学学报》 北大核心 2025年第3期587-596,共10页
Two new Mn(Ⅱ)coordination polymers,namely{[Mn_(2)(HL)(phen)_(3)(H_(2)O)_(2)]·7.5H_(2)O}_n(1)and[Mn_(4)(HL)_(2)(1,4-bib)_(3)(H_(2)O)_(2)]_n(2),were synthesized under hydrothermal conditions by using Mn(Ⅱ)ions an... Two new Mn(Ⅱ)coordination polymers,namely{[Mn_(2)(HL)(phen)_(3)(H_(2)O)_(2)]·7.5H_(2)O}_n(1)and[Mn_(4)(HL)_(2)(1,4-bib)_(3)(H_(2)O)_(2)]_n(2),were synthesized under hydrothermal conditions by using Mn(Ⅱ)ions and 6-(3',4'-dicarboxylphenoxy)-1,2,4-benzenetricarboxylic acid(H_(5)L)in the presence of N-auxiliary ligands 1,10-phenanthroline(phen)and1,4-bis(1H-imidazol-1-yl)benzene(1,4-bib).The structures of coordination polymers 1 and 2 were characterized by infrared spectroscopy,single-crystal X-ray diffraction,thermogravimetric analysis,and powder X-ray diffraction.Single-crystal X-ray diffraction reveals that 1 has a 1D chain structure based on binuclear Mn(Ⅱ)units,while 2 features a(3,8)-connected 3D network structure based on tetranuclear Mn(Ⅱ)units.Magnetic studies show that 1 and 2exhibit antiferromagnetic interactions between manganese ions.2 shows stronger antiferromagnetic interactions due to the shorter Mn…Mn distances within the tetranuclear manganese units.CCDC:2357601,1;2357602,2. 展开更多
关键词 coordination polymers crystal structures binuclear Mnunit tetranuclear Mnunit MAGNETISM
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两例Schiff-base双核Cu_(2)/Ni_(2)配合物的合成、结构及生物活性
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作者 白衡 孙娅 +2 位作者 马鑫 温香平 高晓丽 《化学研究与应用》 北大核心 2025年第5期1162-1170,共9页
利用多齿席夫碱配体H_(2)L(H_(2)L=1-[(2-羟基-1,1-二甲基-乙基亚氨基)-甲基]-萘-2-醇)与M(NO_(3))_(2)·6H_(2)O反应,通过溶剂热法设计与构筑了两例新型双核配合物[M_(2)(L_(2))],分子式为C_(30)H_(30)M_(2)N_(2)O_(4)(1:M=Cu^(2+)... 利用多齿席夫碱配体H_(2)L(H_(2)L=1-[(2-羟基-1,1-二甲基-乙基亚氨基)-甲基]-萘-2-醇)与M(NO_(3))_(2)·6H_(2)O反应,通过溶剂热法设计与构筑了两例新型双核配合物[M_(2)(L_(2))],分子式为C_(30)H_(30)M_(2)N_(2)O_(4)(1:M=Cu^(2+),2:M=Ni^(2+))。单晶X射线衍射测试表明:两个配合物晶体同构,结晶于单斜晶系空间群P2_(1)/c,晶胞结构包含两个M(Ⅱ)离子和两个席夫碱配体L^(2-),两个中心M(Ⅱ)由两个μ_(2)-O桥连形成四边形双核构型。生物活性研究表明,配合物1和2比配体H_(2)L具有更强的抗菌活性。采用紫外光谱法、凝胶电泳法和荧光光谱法研究了化合物与CTDNA的相互作用,结果表明,金属配合物主要通过插入方式与DNA结合,乙二胺(EB)置换实验表明,配合物1、2和配体H_(2)L的淬灭常数分别为0.88、0.66和0.02。 展开更多
关键词 双核配合物 晶体结构 DNA作用 生物活性 抑菌性能
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两个由半刚性羧酸和咪唑衍生物构建的具有螺旋和双核单元的镍基配合物
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作者 刘晓茹 石金莲 +2 位作者 郑亚佳 莫双存 徐中轩 《无机化学学报》 北大核心 2025年第4期797-808,共12页
在水热条件下,4-(1-羧基乙氧基)苯甲酸(H_(2)cba)和Ni(Ⅱ)离子分别与咪唑衍生物1,4-二(1H-咪唑-1-基)苯(1,4-dib)和4,4'-二(1H-咪唑-1-基)-1,1'-联苯(4,4'-dib)反应得到配合物{[Ni(cba)(1,4-dib)(H_(2)O)0.5]·0.5H_(2)... 在水热条件下,4-(1-羧基乙氧基)苯甲酸(H_(2)cba)和Ni(Ⅱ)离子分别与咪唑衍生物1,4-二(1H-咪唑-1-基)苯(1,4-dib)和4,4'-二(1H-咪唑-1-基)-1,1'-联苯(4,4'-dib)反应得到配合物{[Ni(cba)(1,4-dib)(H_(2)O)0.5]·0.5H_(2)O}n(HU21)和{[Ni(cba)(4,4'-dib)(H_(2)O)0.5]·0.5H_(2)O}n(HU22)。单晶衍射结构分析表明配合物HU21和HU22都含有双核的[Ni_(2)(CO_(2))2(H_(2)O)]^(2+)单元。在HU21和HU22中,[Ni_(2)(CO_(2))2(H_(2)O)]^(2+)单元都通过cba2-离子桥接在一起形成一维[Ni_(2)(H_(2)O)(cba)_(2)]_(n)链。进一步分析发现,在配合物HU21中除[Ni_(2)(H_(2)O)(cba)2]n链外,Ni(Ⅱ)离子、水分子和1,4-dib配体还沿b轴形成直径达1.6 nm的右旋和左旋螺旋链。这些右手和左手链按照1∶1的比例连接在一起,构建出HU21所属的空旷的三维结构。[Ni_(2)(H_(2)O)(cba)_(2)]_(n)链填充到该空旷结构中,得到具有点符号为(44.611)的六连接网络框架。不同于HU21中螺旋链可直接形成三维框架,在配合物HU22中,基于Ni(Ⅱ)离子、水分子和4,4'-dib的螺旋链只能够构建出二维结构层。这些二维结构通过[Ni_(2)(H_(2)O)(cba)_(2)]_(n)链作用以ABAB模式堆叠在一起,形成最终六连接网络特征的三维框架。此外,紫外可见吸收光谱证实配合物HU21和HU22属半导体材料,在紫外和可见光区具有较强的光吸收能力。磁性测试则揭示HU21和HU22具有相似的反铁磁性行为。 展开更多
关键词 镍基配合物 双核单元 螺旋链 半导体材料 反铁磁性
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基于胸腺嘧啶三联吡啶的双核铱配合物的发光及抗肿瘤活性研究
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作者 于千水 戚聪 +4 位作者 顾顺心 杨欣达 姜琴 魏荣斌 施鹏飞 《化学学报》 北大核心 2025年第6期579-587,共9页
环金属铱配合物因其优秀的发光性能和良好的光毒性,在双光子光动力疗法(PDT)光敏剂研究领域备受关注.多联吡啶衍生物常被选作铱配合物的配体,考虑到胸腺嘧啶分子拥有两个便于修饰的酰胺基团,将其引入配体有可能会提升生物相容性.将2,2&#... 环金属铱配合物因其优秀的发光性能和良好的光毒性,在双光子光动力疗法(PDT)光敏剂研究领域备受关注.多联吡啶衍生物常被选作铱配合物的配体,考虑到胸腺嘧啶分子拥有两个便于修饰的酰胺基团,将其引入配体有可能会提升生物相容性.将2,2':6',2''-三联吡啶基团与胸腺嘧啶相连接以制备多联吡啶衍生物ttpy,进而制备出含有正二价配位阳离子的双核铱配合物Ir_(2)ttpy.Ir_(2)ttpy在250~350 nm呈现出强配体内电荷转移(ILCT)吸收峰,400~550 nm处呈现弱的金属到配体的荷移跃迁(MLCT)吸收肩峰.Ir_(2)ttpy表现出双重荧光发射,350 nm处发射峰源自tpy基团3LC激发态,而600 nm处的发射则来自配位中心^(3)MLCT激发态.配合物在680~800 nm飞秒激光激发下表现出一定的双光子荧光效应,吸收截面约为24 GM.配合物Ir_(2)ttpy针对4T1乳腺癌细胞表现出一定的光毒性,光毒性指数(PI)值约为18.UV-Vis滴定实验表明配合物Ir_(2)ttpy与DNA有一定的相互结合作用,Autodock模拟显示配合物Ir_(2)ttpy嵌入DNA大沟,并以氢键与DNA的碱基DA-17以及DC-9结合.体外滴定实验表明配合物Ir_(2)ttpy在可见光照射下生成^(1)O_(2)和O_(2)^(-)·,能够光催化氧化烟酰胺腺嘌呤二核苷酸(NADH).细胞成像结果也显示配合物Ir_(2)ttpy能在光照下生成活性氧物种(ROS).配合物Ir_(2)ttpy的抗肿瘤活性与其诱导生成ROS以及与DNA相互结合有关,二者协同作用而导致肿瘤细胞死亡. 展开更多
关键词 胸腺嘧啶 双核铱配合物 抗肿瘤 活性氧物种(ROS) DNA
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Synthesis and Structural Determination of Binuclear Nine-Coordinate K_4[Y_2(Httha)_2]·14H_2O 被引量:4
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作者 WANG Jun ZHANG Xiang dong MA Rui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第3期237-241,共5页
A Y 3+ complex with triethylenetetraaminehexaacetic acid was prepared and its composition and structure were determined as K 4[Y 2(Httha) 2]·14H 2O by elemental analysis and single crystal X ray four circle diffr... A Y 3+ complex with triethylenetetraaminehexaacetic acid was prepared and its composition and structure were determined as K 4[Y 2(Httha) 2]·14H 2O by elemental analysis and single crystal X ray four circle diffraction analysis. In the binuclear complex, the two YN 3O 6 parts all form nine coordinate monocapped square anti prismatic structures. There are a lot of water molecules in the unit cell which form hydrogen bonds. 展开更多
关键词 Y 3+ Triethylenetetraaminehexaacetic acid binuclear complex STRUCTURE
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Synthesis and Crystal Structure of a Novel Binuclear Copper(Ⅱ) Complex, [Cu(paba)Cl] 被引量:5
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作者 欧阳淼 赵志愿 +2 位作者 石月花 张运良 蒋毅民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第4期457-460,共4页
A novel binuclear Cu(Ⅱ) complex [Cu(paba)Cl] (pabaH = 2-(2-pyridylmethylimine)benzenesulfonic acid) has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The c... A novel binuclear Cu(Ⅱ) complex [Cu(paba)Cl] (pabaH = 2-(2-pyridylmethylimine)benzenesulfonic acid) has been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal of the title complex crystallizes in a monoclinic system, space group P21/n, with a = 6.8165(7), b = 15.3073(16), c = 12.3795(13) A^°, β= 95.0160(10)°, V= 1286.8(2) A^°^3, Mr = 360.26, Dc= 1.860 g/cm^3,μ = 2.074 mm^-1, F(000) = 724, Z = 4, the final R = 0.0252 and wR = 0.0675 for 2395 observed reflections with I 〉 20(I). The title complex is centrosymmetric and a pair of chlorides act as μ2-bridges to link two Cu(Ⅱ) ions forming a binuclear complex. Every Cu(Ⅱ) ion is five-coordinated by pyridyl N, imine N and sulfonate O atoms of the tridentate paba ligand as well as two bridging Cl^-, constructing the distorted square-pyramidal geometry. In the structure extensive hydrogen bonds and weak π-π stacking stabilize the solid structures, through which the complex builds its 3-dimensional supramolecular structure. 展开更多
关键词 binuclear complex 2-pyridinecarboxaldehyde Schiff base crystal structure
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Electrocatalytic oxidation of methanol at platinum electrode modified with Eu-Fe cyanide-bridged binuclear complexes 被引量:3
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作者 Ma, Yong Jun Pan, Yu Ying +2 位作者 Wang, Wei Feng Yang, Mei Xia Zhou, Min 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期337-340,共4页
The electrocatalytic oxidation of methanol at the platinum electrode modified with Eu-Fe cyanide-bridged binuclear complexes (Eu-Fe film) was investigated for the first time by cyclic voltammetry.Compared with the bar... The electrocatalytic oxidation of methanol at the platinum electrode modified with Eu-Fe cyanide-bridged binuclear complexes (Eu-Fe film) was investigated for the first time by cyclic voltammetry.Compared with the bare platinum electrode,the results showed that the modified electrode had excellent electrocatalytic activity for the oxidation of methanol;the oxidation peak potential shifted more negatively and the peak current increased about twenty times.The electrooxidation of methanol at the modified elect... 展开更多
关键词 METHANOL ELECTROCATALYSIS Cyanide-bridged binuclear complexes EUROPIUM Chemically modified electrode
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Binuclear and Hexanuclear Ti(Ⅳ) Complexes Supported by [OOOO]^(4–)-type Ligand for Preparing Disentangled UHMWPE 被引量:2
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作者 Vladislav A.Tuskaev Svetlana Ch.Gagieva +9 位作者 Dmitry A.Kurmaev Viktor G.Vasil'ev Nikolay A.Kolosov Sergey V.Zubkevich Elena S.Mikhaylik Evgenii K.Golubev Galina G.Nikiforova Pavel A.Zhizhko Olga A.Serenko Boris M.Bulychev 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2019年第5期471-477,共7页
Binuclear and hexanuclear titanium complexes stabilized by tetradentate [OOOO]^(4–)-type ligand were active in ethylene polymerization in the presence of Et2 AlCl/Bu2 Mg binary co-catalyst, giving high molecular weig... Binuclear and hexanuclear titanium complexes stabilized by tetradentate [OOOO]^(4–)-type ligand were active in ethylene polymerization in the presence of Et2 AlCl/Bu2 Mg binary co-catalyst, giving high molecular weight polyethylene. The binuclear complex showed significantly higher catalytic activity and thermal stability in comparison to mononuclear analogue. Ultra high molecular weight polyethylene(UHMWPE) samples were processed by a solid-state uniaxial deformation into high-strength(up to 2.5 GPa) and highmodulus(over 100 GPa) oriented film tapes, which indirectly indicates a low degree of entanglements between the macromolecular chains. 展开更多
关键词 binuclear catalysts Titanium Ethylene ZIEGLER-NATTA polymerization UHMWPE
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Synthesis and Crystal Structure of an Azide Bridged Binuclear Zinc(Ⅱ) Dimer Containing Taurine Schiff Base [Zn_2(C_8H_9N_2O_3S)_2·(N_3)_2·(H_2O)_2]_2·_2H_2O 被引量:3
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作者 JIANG Yi-Min LI Jia-Ming +1 位作者 XIE Fu-Qing WANG Yan-Fei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第7期767-770,共4页
The title complex [Zn2L2(N3)2(H2O)2]·2H2O (L = N-(2-pyridylmethylidene) taurine) has been synthesized in a methanol-water solution. The crystal belongs to monoclinic, space group P2 1/C with a = 15.8064... The title complex [Zn2L2(N3)2(H2O)2]·2H2O (L = N-(2-pyridylmethylidene) taurine) has been synthesized in a methanol-water solution. The crystal belongs to monoclinic, space group P2 1/C with a = 15.8064(10), b = 10.5015(5), c = 17.3193(11) ,A, β= 111.314(2)°, V = 2678.2 (3) ,A ^3 C16H26N10O10S2Zn2, Mr = 713.33, Z = 4, DC = 1.769 g/cm^3, μ = 2.017 mm^-1 and F(000) = 1456. The asymmetric unit consists of two half-molecules of the complex and two water molecules. Four N and two O atoms form the coordination environment of each Zn atom, resulting in a distorted octahedral configuration. The two halves of each independent dimer are related by a crystallographic inversion centre, which lies at the centre of the ring formed by two Zn atoms and the coordinating atoms of the two azide anions. The average separation of Zn(Ⅱ)...Zn(Ⅱ) is 3.322 A. The molecules are linked by O-H...O hydrogen bonds, generating an interesting zigzag infinite chain structure in the ac plane. 展开更多
关键词 binuclear zinc complex N-(2-pyridylmethylidene)-taurine schiff base bridging azide crystal structure
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Hydrothermal Synthesis, Crystal Structure and Fluorescence Properties of a Three-dimensional Triply-bridged Binuclear Zinc(Ⅱ) Complex [Zn_2(Mba)_3(Phen)_2EtOH)]·ClO_4 被引量:2
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作者 陈志敏 冯泳兰 +3 位作者 杨颖群 李薇 易正戟 陈满生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第12期1803-1809,共7页
The novel complex [Zn2(Mba)3(Phen)2EtOH)]·ClO4 (Hrnba = methoxybenzoic acid, Phen = 1,10-phenanthroline, EtOH = ethanol) was synthesized by hydrothermal reactions, and its structure was determined by X-ray... The novel complex [Zn2(Mba)3(Phen)2EtOH)]·ClO4 (Hrnba = methoxybenzoic acid, Phen = 1,10-phenanthroline, EtOH = ethanol) was synthesized by hydrothermal reactions, and its structure was determined by X-ray diffraction. The crystal belongs to the triclinic system, space group Pi with a = 1.15362(1), b = 1.3655(3), c = 1.61451(1) nm, α= 72.842(2), β = 83.259(3), y = 72.083(2)°, V = 2.3112(6) nm3, Z = 2,μ(MoKa) = 11.71 cm-1, F(000) = 1120, R = 0.0552 and wR = 0.1157 (I 〉 2σ(I)). The two centric zinc(H) ions in the complex locate in a distorted octahedral coordination geometry and a distorted trigonal bipyramid coordination geometry, respectively. Two bridging bidentate carboxyl groups and a μ2-O carboxyl group from three methoxybenzoic acids act as the bridge to link two Zn(Ⅱ) ions. The asymmetric units are connected by π-π packing interactions between aromatic rings to form a three-dimensional supramolecular network. The experimental results show a good fluorescence property for the complex. 展开更多
关键词 hydrothermal synthesis binuclear zinc(Ⅱ) complex triply-bridged crystal structure luminescence property
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Synthesis and Crystal Structure of a Binuclear Gadolinium(Ⅲ) Complex Bridged by Cucurbit[6]uril 被引量:2
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作者 Gui Ling ZHANG Zhi Yong WU +2 位作者 Yan Tuan LI Da Qi WANG Jian Min DOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第1期93-96,共4页
A new cucurbit[6]uril bridsed binuclear complex {[Gd(H2O)6]2[Q6(H2O)]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows th... A new cucurbit[6]uril bridsed binuclear complex {[Gd(H2O)6]2[Q6(H2O)]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows that the complex has an extended cucurbit[6]uril-bridged structure consisting of two gadolinium(Ⅲ) ions, in which each gadolinium(Ⅲ) ion is coordinated with two neighboring carbonylic oxygen atoms of Q6 and six oxygen atoms of water molecules that leans toward one side of the portal. One disordered vip water molecule resides in the Q6 molecule cavity and occupies two different positions. Hydrogen bonds assemble the complcx to threedimensional supramolecular structure. 展开更多
关键词 uril binuclear gadolinium(Ⅲ) complex crystal structure
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Synthesis and Characterization of Two Binuclear Macrocyclic Zinc(Ⅱ) Complexes by Anion Exchange 被引量:2
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作者 欧光川 黄中文 +2 位作者 潘泽毅 周东来 袁先友 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第6期903-908,共6页
Two macrocyclic zinc(Ⅱ) complexes {[ZnL(VO3)2]·0.33H2O}n(1) and [ZnL(H2O)2][Ni(CN)4](2)(L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) have been obtained from the reactions of [Z... Two macrocyclic zinc(Ⅱ) complexes {[ZnL(VO3)2]·0.33H2O}n(1) and [ZnL(H2O)2][Ni(CN)4](2)(L = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) have been obtained from the reactions of [ZnL](ClO4)2 with NH4VO3 and K2[Ni(CN)4], respectively, and structurally characterized by elemental analysis, IR, XRPD, TG and X-ray diffraction. Single-crystal X-ray diffraction analyses indicated that the Zn(Ⅱ) atom lies on an inversion center and is octahedrally coordinated by four nitrogen atoms of the tetradentate macrocyclic ligand in the equatorial plane and two oxygen atoms of [VO4] tetrahedra in the axial positions in 1, and two oxygen atoms of two water molecules in 2. Complex 1 shows a three-dimensional structure, which is constructed by the links of [VO3]nn- chains with [ZnL]2+, forming one-dimensional channels occupied by vip water molecules. The monomers of [ZnL(H2O)2]2+ and [Ni(CN)4]2- are connected through the intermolecular hydrogen bonds to form a two-dimensional sheet in complex 2. 展开更多
关键词 macrocyclic zinc(Ⅱ) complexes binuclear VANADIUM anion exchange
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A Two-dimensional Anthracene-9,10-dicarboxylate Zinc(Ⅱ) Coordination Polymer Based on Binuclear [Zn_2Cl_2] Nodes: Synthesis, Characterization and Luminescent Properties 被引量:2
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作者 王军杰 张仁春 +2 位作者 张道军 常泽 章应辉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第5期695-700,共6页
A two-dimensional(2D) 44 topological ZnⅡ coordination polymer {[Zn2Cl2(L)(4bpy)2]}∞(H2L = anthracene-9,10-dicarboxylic acid, 4bpy = 4,4ˊ-bipyridine) based on binuclear [Zn2Cl2] nodes has been synthesized an... A two-dimensional(2D) 44 topological ZnⅡ coordination polymer {[Zn2Cl2(L)(4bpy)2]}∞(H2L = anthracene-9,10-dicarboxylic acid, 4bpy = 4,4ˊ-bipyridine) based on binuclear [Zn2Cl2] nodes has been synthesized and characterized by IR, elemental analysis, X-ray powder diffraction and single-crystal X-ray diffraction analysis. Moreover, the luminescent properties of the correspon- ding compound have been briefly investigated. 展开更多
关键词 zinc(Ⅱ) coordination polymer anthracene-9 10-dicarboxylic acid binuclear [Zn2Cl2] nodes luminescent properties
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Hydrothermal Synthesis, Crystal Structure and Properties of One Binuclear Nickel(Ⅱ) Complex with 3-(2-Pyridiyl)-1H-1,2,4-triazole 被引量:2
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作者 李昶红 李薇 +1 位作者 李安伍 谭雄文 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第6期1004-1008,共5页
A new binuclear nickel(Ⅱ) complex [Ni_2(C_7 N_4 H_5)_3(C_9 H_9 O_2)]n has been hydrothermally synthesized with nickel sulfate, 3-(pyridin-2-yl)-1H-1,2,4-triazole and 3,5-dimethylbenzoic acid(3,5-DMBA). It c... A new binuclear nickel(Ⅱ) complex [Ni_2(C_7 N_4 H_5)_3(C_9 H_9 O_2)]n has been hydrothermally synthesized with nickel sulfate, 3-(pyridin-2-yl)-1H-1,2,4-triazole and 3,5-dimethylbenzoic acid(3,5-DMBA). It crystallizes in the triclinic space group P1 with a = 11.5769(7), b = 12.3115(7), c = 12.6431(7) A, α = 81.4860(10)o, β = 64.2830(10)o, γ = 63.7130(10)o, V = 1453.45(15) A^3, D_c = 1.604 g/cm^3, Z = 2, F(000) = 720, the final GOOF = 1.048, R = 0.0285 and wR = 0.0628. The crystal structure shows that the whole molecule consists of two nickel ions bridged by three μ_2-η~1:η~0-3-(pyridin-2-yl)-1,2,4-triazole anions. The coordination environment of Ni(Ⅱ) ion is NiO_2 N_4 and NiN_5, giving a distorted octahedral geometry and square pyramidal geometry respectively. The luminescence and thermal properties of the complex were investigated. 展开更多
关键词 binuclear nickel(Ⅱ) complex LUMINESCENCE thermal properties
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Synthesis, Crystal Structure and Properties of a New Binuclear Copper(Ⅱ) Complex with 5-Oxo-4-oxa-tricyclo[4.2.1.0]nonane-9-carboxylic Acid(TNCA) 被引量:2
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作者 李薇 李玉林 +1 位作者 李昶红 谭雄文 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第5期819-824,共6页
A new binuclear copper(Ⅱ) complex [Cu2(Hpt)2(TNCA)2(H2O)2]·4 H2O(1) has been synthesized with copper acetate, 5-oxo-4-oxa-tricyclo[4.2.1.0]nonane-9-carboxylic acid(TNCA) and 3-(pyridin-2-yl)-1,2,4-... A new binuclear copper(Ⅱ) complex [Cu2(Hpt)2(TNCA)2(H2O)2]·4 H2O(1) has been synthesized with copper acetate, 5-oxo-4-oxa-tricyclo[4.2.1.0]nonane-9-carboxylic acid(TNCA) and 3-(pyridin-2-yl)-1,2,4-triazole(Hpt). It crystallizes in the triclinic space group P-1, with a = 8.8199(18), b = 14.278(3), c = 15.269(3) A, α = 76.21(3)o, β = 81.07(3)o, γ = 76.07(3)o, V = 1802.7(6) A3, Dc = 1.636 g/cm3, Z = 2, F(000) = 916, the final GOOF = 1.051, R = 0.0556 and wR = 0.1388. The whole molecule consists of two copper ions bridged by two μ2-η^1:η^0-3-(pyridin-2-yl)-1,2,4-triazole anions. The coordination environment of the Cu(1) ion is CuO2N3, giving a distorted square pyramidal geometry. 1 exhibits antiferromagnetic interaction between Cu(Ⅱ) ions, the electron transfer of 1 is irreversible in electrode reactions and the TG analysis shows that 1 is stable below 440 K. 展开更多
关键词 binuclear copper(Ⅱ) complex thermal stability electrochemical and magnetic properties
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