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Insight into Hydrolytic Stability and Tribological Properties of B-N Coordination Tung Oil-Based Lubricant Additive in Water
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作者 Na Yao Haiyang Ding +4 位作者 Mei Li Pengcheng Wang Shouhai Li Lina Xu Xiaohua Yang 《Journal of Renewable Materials》 SCIE EI 2023年第3期1367-1381,共15页
A tung oil-based boron-nitrogen coordination polymer(TWE-BN)was specially designed and synthesized as a highly efficient water-based lubricant additive,which has been beneficial to both energy conservation and conduci... A tung oil-based boron-nitrogen coordination polymer(TWE-BN)was specially designed and synthesized as a highly efficient water-based lubricant additive,which has been beneficial to both energy conservation and conducive to environmental protection.Its hydrolysis stability and tribological properties in water were investigated.To better research the lubricating properties,and thus to understand the interaction between the surface and the lubricating additives.Herein,both experimental and theoretical computations based on density functional theory(DFT)were performed.The addition of TWE-BN reduces the water friction coefficient and wear scar diameter,and the maximum non-seizure load increased from 93 to 726 N.Moreover,the anti-corrosion ability on copper was classified as 1b level.The stainless-steel surface was analyzed using scanning electron microscopy(SEM)and X-ray photoelectron spectroscopy(XPS).In hydrolytic stability testing,TWE-BN was better than nitrogen-free tung oil-based lubricant additive(TWE-B)and remained non-hydrolyzed for at least 15 days,implying the feasibility of tung oil-based boron-nitrogen coordination as highly effective and hydrolytic stability lubricant additives. 展开更多
关键词 Tribological properties tung oil BORATE hydrolytic stability boron-nitrogen coordination
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Syntheses and Crystal Structures of Two 3D Zinc(II) Compounds Involving Coordination and Hydrogen Bonds 被引量:2
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作者 CHEN Bai-Quan HAN Lei +3 位作者 WU Ben-Lai WU Ming-Yan HUANG You-Gui HONG Mao-Chun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第5期527-532,共6页
Two zinc(Ⅱ) compounds, [Zn(L)(H2O)2]n 1 and [Zn(4,4'-bpy)(H2O)4](L) 2 (H2L = trans,trans-1,3 butadiene 1,4-dicarboxylic acid), were synthesized by hydrothermal methods and characterized by single-cryst... Two zinc(Ⅱ) compounds, [Zn(L)(H2O)2]n 1 and [Zn(4,4'-bpy)(H2O)4](L) 2 (H2L = trans,trans-1,3 butadiene 1,4-dicarboxylic acid), were synthesized by hydrothermal methods and characterized by single-crystal X-ray diffraction analyses. Compound 1 crystallizes in monoclinic, space group C2/c with a=15.4970(16), b = 5.4976(6), c = 10.7113(12) A, β=96.298(6)°, C6H8O6Zn, Mr = 241.50, V = 907.06(17) A^3, Z = 4, D, = 1.768 g/cm^3, F(000) = 488,μ = 2.703 mm^-1, S = 1.060, the final R = 0.0256 and wR = 0.0660 for 968 observed reflections with Ⅰ 〉 2σ(Ⅰ). Compound 2 crystallizes in triclinic, space group P1^- with a = 6.915(2), b = 7.166(2), c = 10.363(3) A, α = 73.250(4), β = 84.429(4), γ = 61.605(3)°, C16H2ON2O8Zn, Mr = 433.70, V = 432.1 (2) A^3, Z = 1, D, = 1.667 g/cm^3, F(000) = 224 and μ= 1.471 mm^-1, S = 1.118, the final R = 0.0486 and wR = 0.1077 for 1352 observed reflections with Ⅰ〉 2σ(Ⅰ). Upon using the assembly strategy of combination of coordination polymer chains with intermolecular hydrogen bonds, three-dimensional frameworks of complexes 1 and 2 were formed. 展开更多
关键词 Zn(Ⅱ) coordination polymer hydrogen bonds crystal structure
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STUDY ON THE CARDANOL-ALDEHYDE CONDENSATION POLYMER CONTAINING BORON-NITROGEN COORDINATE BOND 被引量:1
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作者 林金火 胡炳环 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第3期219-225,共7页
Cardanol-aldehyde condensation polymer containing boron-nitrogen coordinate bond (CFBN) has been synthesized and characterized by IR, XPS, HPLC and DTA-TG. Its properties were also investigated. The results show tha... Cardanol-aldehyde condensation polymer containing boron-nitrogen coordinate bond (CFBN) has been synthesized and characterized by IR, XPS, HPLC and DTA-TG. Its properties were also investigated. The results show that the coating film of CFBN has excellent physico-mechanical properties, good anticorrosive properties and stable at high temperature. (Author abstract) 8 Refs. 展开更多
关键词 CARDANOL cardanol-aldehyde condensation polymer B-N coordinate bond
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Structure and Fluorescence Property of a 2D Bilayer Cd(Ⅱ) Coordination Polymer Induced by H-bonding and π-π Interaction 被引量:4
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作者 胡劲松 刘希慧 +2 位作者 何杰 石建军 邢宏龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第5期739-743,共5页
Solvothermal reactions of 4,4'-oxybis(benzoic acid) (H2oba) with 1,3-dipyridyl benzene (1,3-dpb) produced a two-dimensional (2D) cadmium(Ⅱ) coordination polymer {[Cd(oba)(dpb)]·H2O}n (1). The co... Solvothermal reactions of 4,4'-oxybis(benzoic acid) (H2oba) with 1,3-dipyridyl benzene (1,3-dpb) produced a two-dimensional (2D) cadmium(Ⅱ) coordination polymer {[Cd(oba)(dpb)]·H2O}n (1). The complex was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with a = 13.6692(9), b = 25.9647(17), c = 8.7912(6) , α = 125.0370(10), γ = 2544.7(3)°, V = 2544.7(3) 3, C30H22N2O6Cd, Mr = 618.91, Dc =1.609 g/cm3, F(000) = 1248, μ = 0.904 mm-1 and Z = 4. The neighboring Cd(Ⅱ) ions are linked by oba2-anions and 1,3-dpb to form an infinitely 2D wavelike sheet, and two such 2D sheets are interlocked with each other by H-bonding to form a 2D → 2D structure. The adjacent two groups of interlocked structures are further linked to form a bilayer 2D supramolecular network by π-π interactions. In addition, the fluorescence property of 1 was also studied. 展开更多
关键词 coordination polymer H-bonding ^-n interaction FLUORESCENCE
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Quasi-plane-hypothesis of strain coordination for RC beams seismically strengthened with externally-bonded or near-surface mounted fiber reinforced plastic 被引量:3
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作者 Ren Zhenhua Zeng Xiantao +1 位作者 Liu Hanlong Zhou Fengjun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第1期67-76,共10页
The application of fiber reinforced plastic(FRP),including carbon FRP and glass FRP,for structural repair and strengthening has grown due to their numerous advantages over conventional materials such as externally b... The application of fiber reinforced plastic(FRP),including carbon FRP and glass FRP,for structural repair and strengthening has grown due to their numerous advantages over conventional materials such as externally bonded reinforcement(EBR) and near-surface mounted(NSM) strengthening techniques.This paper summarizes the results from 21 reinforced concrete beams strengthened with different methods,including externally-bonded and near-surface mounted FRP,to study the strain coordination of the FRP and steel rebar of the RC beam.Since there is relative slipping between the RC beam and the FRP,the strain of the FRP and steel rebar of the RC beam satisfy the quasi-plane-hypothesis;that is,the strain of the longitudinal fiber that parallels the neutral axis of the plated beam within the scope of the effective height(h 0) of the cross section is in direct proportion to the distance from the fiber to the neutral axis.The strain of the FRP and steel rebar satisfies the equation:ε FRP =βε steel,and the value of β is equal to 1.1-1.3 according to the test results. 展开更多
关键词 strain coordination quasi-plane-hypothesis external-bonded near-surface mounted fiber reinforced plastic strengthening concrete beam
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CHARACTERIZATION AND PROPERTIES OF URUSHIOL POLYMER CONTAINING BORON-NITROGEN COORDINATE BOND
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作者 林金火 陈文定 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1997年第4期305-310,共6页
Urushiol polymer containing B-N bond (PUBN) was synthesized with urushiol-boron polymer and diethylene triamine. Its structure was characterized by XPS, IR, UV, HPLC, DTA-TG and elemental analysis. The physico-mechani... Urushiol polymer containing B-N bond (PUBN) was synthesized with urushiol-boron polymer and diethylene triamine. Its structure was characterized by XPS, IR, UV, HPLC, DTA-TG and elemental analysis. The physico-mechanical and anticorrosive properties of the polymer were also investigated. The results show that the coating of PUBN can be hardened in 2 h at room temperature and its film has excellent physico-mechanical properties and good anticorrosive properties. 展开更多
关键词 urushiol-boron polymer diethylene triamine B-N coordinate bond
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Bond-Valence Sum and Distortion of Coordination Polyhedra
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作者 章礼明 《Chinese Journal Of Geochemistry》 EI CAS 1993年第1期92-96,共5页
By using the Lagrange's intermediate value theorem,it is derived mathematically that the structur-al distortion of a coordination polyhedron may lead to an increase in bond-valence sum of the cen-tral atom of ion ... By using the Lagrange's intermediate value theorem,it is derived mathematically that the structur-al distortion of a coordination polyhedron may lead to an increase in bond-valence sum of the cen-tral atom of ion .The applicabilities of the bond-valence model are discussed in the following two cases:the modeling of crystal structure ,and the indication of distortion degree of a coordination polyhedron.Also it is shown that a distorted polyhedron should be in favor of a longer average bond length or a smaller coordination number. 展开更多
关键词 化合价 无机晶体结构 拉格朗日中值定理 多面体
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Synthesis and Crystal Structure of a 1D Chained Coordination Polymer Containing One-dimensional Egg-like Channels:{[Cu_2(C_2O_4)_2(inta)_4](inta)}_n (inta=Isonicotinamide) 被引量:3
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作者 李秀梅 王庆伟 +2 位作者 李丹 赵霞 高广刚 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第11期1341-1344,共4页
A new one-dimensional copper coordination polymer chain has been prepared and fully characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The compound { [Cu2(C2O4)2(inta)4](i... A new one-dimensional copper coordination polymer chain has been prepared and fully characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The compound { [Cu2(C2O4)2(inta)4](inta)}n 1 crystallizes in the triclinic system, space group P1, with a = 8.4722(5), b = 10.9825(6), c = 11.6128(6)A, α= 104.8050(10),β = 102.5740(10), γ= 109.6890(10)°, V= 927.18(9) A3, Mr = 929.79, Z = 1, Dc = 1.665 g/cm^3, F(000) = 475, μ = 1.231 mm^-1, R = 0.0453 and wR = 0.1185 for 3290 observed reflections (Ⅰ 〉 2σ(Ⅰ)). Of the compound, the Cu center is octahedrally coordinated with oxalate acting as a tetra-dentate ligand coordinated to the copper atom and each inta serving as a terminal ligand by employing only one N-donor to coordinate with the Cu center. An infinite {Cu2(C2O4)2}∞ chain is formed along the c axis. Furthermore, the 1D chains are held together via extensive hydrogen-bonding interactions to generate a three-dimensional network with 1D channels (ca. 5.491A×11.507A) where inta molecules are filled. 展开更多
关键词 coordination polymer hydrogen bond copper crystal structure
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Hydrothermal Synthesis and Crystal Structure of a Zinc(Ⅱ)Coordination Polymer Assembled by Dpphen and H_2btec/btec 被引量:3
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作者 LI Xiu-Mei NIU Yan-Ling +1 位作者 WANG Qing-Wei LIU Bo 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第7期1122-1126,共5页
A new metal-organic coordination polymer [Zn2(dpphen)2(H2btec)(btec)0.5]n (dpphen = 4,7-diphenyl- 1,10-phenanthroline, H4btec = 1,2,4, xylic acid) 1 was obtained via hydrotherrnal synthesis and characterized b... A new metal-organic coordination polymer [Zn2(dpphen)2(H2btec)(btec)0.5]n (dpphen = 4,7-diphenyl- 1,10-phenanthroline, H4btec = 1,2,4, xylic acid) 1 was obtained via hydrotherrnal synthesis and characterized by elemental analysis, TG; IR spectrum and single-crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group P2 1/n with a = 16.2996(14), b = 14.3332(12), c = 25.247(2) A, β = 103.4050(10)°, V= 5737.7(9) A), C63H37N4O12Zn2, Mr = 1172.71, Dc = 1.358 g/cm3,μ(MoKα) = 0.902 mm^-1, F(000) = 2396, Z = 4, the final R = 0.0684 and wR = 0.1281 for 3728 observed reflections (1 〉 2σ(I)). It exhibits a two-dimensional network structure constructed by mixed ligands of dpphen and H2btec/btec. 展开更多
关键词 hydrogen bond crystal structure coordination polymer
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A New Co(Ⅱ) Coordination Polymer Based on a Flexible 1,4-Cyclohexanedicarboxylic Acid: Synthesis, Structure and Thermal Behavior 被引量:2
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作者 王秀艳 李聪 +3 位作者 邹春凯 阚若飞 张晓旭 徐占林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第12期2155-2160,共6页
A new Co(Ⅱ) coordination polymer, [Co(1,4-chdc)(L)(H2O)]n(1), was synthesized under hydrothermal condition(1,4-H2chdc = 1,4-cyclohexanedicarboxylic acid, L = 2-(4-fluoro-phenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline... A new Co(Ⅱ) coordination polymer, [Co(1,4-chdc)(L)(H2O)]n(1), was synthesized under hydrothermal condition(1,4-H2chdc = 1,4-cyclohexanedicarboxylic acid, L = 2-(4-fluoro-phenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline). Its crystal structure was determined by single-crystal X-ray diffraction. 1 crystallizes in triclinic, space group P1 with a = 8.790(5), b = 10.486(5), c = 13.305(5)A, α = 87.391(5), β = 82.925(5), γ = 81.841(5)°, V = 1204.2(10)A^3, Z = 2, C27H23FN4O5Co, Mr = 561.42, Dc = 1.548 g/cm^3, F(000) = 578, μ(Mo Ka) = 0.769 mm^-1, R = 0.0415 and wR = 0.1043. In 1, each 1,4-chdc anion bridges two neighboring Co(Ⅱ) atoms to give a chain structure. The L ligands are attached on one side of the chain through chelating the Co(Ⅱ) atoms, and are stacked with those of an adjacent chain through π-π interactions, yielding a double-chain structure. The double-chain structures are linked into a supramolecular layer structure through N–H…O hydrogen-bonding interactions between the adjacent double-chain structures. Moreover, the thermal behavior of 1 was also studied. 展开更多
关键词 cobalt coordination polymer 1 4-cyclohexanedicarboxylic acid π-πinteractions hydrogen bond thermal behavior
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Hydrothermal synthesis and structural studies of a new coordination polymer of lanthanum(Ⅲ) with benzene-1,2,4,5-tetracarboxylic acid and 4,4′-bipyridine 被引量:1
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作者 Masoumeh Tabatabaee Mahboubeh A. Sharif +1 位作者 Fatemeh Vakili Saina Saheli 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第3期357-362,共6页
A new lanthanum complex formulated as {(bpyH2)[La(btc)(H2O)4(NO3)]·2H2O}n (1) (btcH4=benzene-1,2,4,5-tetracarboxylic acid; bpy=4,4'-bipyridine) was hydrothermally synthesized. The complex was charact... A new lanthanum complex formulated as {(bpyH2)[La(btc)(H2O)4(NO3)]·2H2O}n (1) (btcH4=benzene-1,2,4,5-tetracarboxylic acid; bpy=4,4'-bipyridine) was hydrothermally synthesized. The complex was characterized by FT-IR spectroscopy, elemental analysis and X-ray diffraction. X-ray crystal structural analysis revealed that the compound belonged to the monoclinic space group C2/c with cell parameters a= 1.42806(7) nm, b=1.10258(5) nm, c=1.60333(8) nm and β=101.9400(10)°. The complex was polymeric with La^III atoms linked by four O atoms from two carboxylate groups of one benzene-1,2,4,5-tetracarboxylate. The LaIn atom was ten coordinated in a distorted tetracapped trigonal prism. In the crystal structure, a wide range of noncovalent interactions consisting of hydrogen bonding (of the types of O-H…O, N-H…O and C-H…O) and ion pairing interactions connected the various components into a supramolecular structure. 展开更多
关键词 lanthanum(III) complex hydrothermal synthesis coordination polymer hydrogen bonding benzene-1 2 4 5-tetracarboxylic acid rare earths
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A Zn(Ⅱ) Coordination Polymer Based on a Flexible Symmetric Multicarboxylate Ligand 被引量:1
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作者 李斌 叶闰平 +2 位作者 覃业燕 杨锦霞 姚元根 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第10期1624-1630,共7页
A novel coordination polymer, namely [Zn2(CAPA)(DMA)(H2O)]2n·n(H2O)(1,H4CAPA = 5-(bis(4-carboxybenzyl) amino) isophthalic acid, DMA = N,N-dimethylacetamide) has been synthesized through a solvotherm... A novel coordination polymer, namely [Zn2(CAPA)(DMA)(H2O)]2n·n(H2O)(1,H4CAPA = 5-(bis(4-carboxybenzyl) amino) isophthalic acid, DMA = N,N-dimethylacetamide) has been synthesized through a solvothermal method and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectra, and thermogravimetric analyses. The crystal structure is of monoclinic, space group P21/n with a = 8.0585(5), b = 18.9733(10), c = 20.2044(14) A^°3, β = 101.144(7)°, V = 3030.9(3) ?~3, C56H54Zn4N4O21, Mr = 1378.58, Z = 2). The compound forms a three-dimensional(3D) supramolecular framework by linking adjacent layers via hydrogen bonds and π···π interactions. It is interesting that the crystal structure is much related to the flexibility and configuration of the ligand. In addition, the thermal stability and luminescence properties for the compound have also been investigated. 展开更多
关键词 5-(bis(4-carboxybenzyl) amino) isophthalic acid coordination polymer hydrogen bonds luminescent property
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1D Lanthanide Coordination Polymers Based on 3-(Pyridin-4-yl)benzoic Acid: Syntheses, Structures and Luminescent Properties 被引量:4
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作者 肖雪英 韦永勤 +1 位作者 郑文旭 吴克深 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1543-1550,共8页
ABSTRACT Four novel 1D lanthanide coordination polymers with formula [Ln(3,4-pybz)3(HzO)2. H2O]n (Ln = 1 Sm; 2 Eu; 3 Tb; 4 Dy, 3,4-Hpybz = 3-(pyridin-4-yl)benzoic acid) have been synthesized by hydrothermal re... ABSTRACT Four novel 1D lanthanide coordination polymers with formula [Ln(3,4-pybz)3(HzO)2. H2O]n (Ln = 1 Sm; 2 Eu; 3 Tb; 4 Dy, 3,4-Hpybz = 3-(pyridin-4-yl)benzoic acid) have been synthesized by hydrothermal reactions of lanthanide oxide and 3-(pyridine-4-yl) benzoic acid. Single-crystal X-ray diffraction shows that the four compounds are isostructural. They all crystallize in a monoelinic system, space group P1^-. They have a doubly carboxylate-bridged infinite-chain structure with alternating Ln-(carboxylate)2-Ln linkages and one chelating carboxylate group on each metal center. The Ln ion also combines to two water molecules to form an eight-coordinate square antiprismatic geometry. The pyridine nitrogen atoms of the ligand do not coordinate to the metal centers but direct the formation of a 3D network through hydrogen bonding with coordinated water molecules. The photoluminescent properties of 2 and 3 have been also studied. 展开更多
关键词 lanthanide coordination polymer 3-(pyridine-4-yl) benzoic acid HYDROGEN-bondING photoluminescence
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Syntheses and Structures of Three Novel 1-D Lanthanide-isonicotinate Coordination Polymers 被引量:1
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作者 XU Jing HAN Jia-Jun +1 位作者 ZHENG Shou-Tian YANG Guo-Yu 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第7期866-872,共7页
Three novel lanthanide-IN coordination polymers [Ln(IN)3(H2O)2], (Ln = Sm 1, Dy 2, Eu 3; IN = isonicotinate) have been hydrothermally synthesized and characterized by FT-IR spectra, elemental analysis and TG an... Three novel lanthanide-IN coordination polymers [Ln(IN)3(H2O)2], (Ln = Sm 1, Dy 2, Eu 3; IN = isonicotinate) have been hydrothermally synthesized and characterized by FT-IR spectra, elemental analysis and TG analysis. Single-crystal X-ray diffraction shows that 1, 2 and 3 are isostructural. Crystal data for 1: monoclinic, space group C 2/c, a = 15.8384(14), b = 14.2662 (12), c = 9.5073(7) A, β = 97.705(4)°, V = 2128.8(3) A^3, Z = 4, Dc = 1.724 g/cm^3, F(000) = 1084 , μ = 2.806 mm^-1 and R = 0.0226; Crystal data for 2: monoclinic, space group C 2/c, a = 15.7890(3), b = 14.1356(6), c = 9.5152(3) A, β= 97.899(2)°, V = 2103.52(12) A^3, Z = 4, Dc = 1.784 g/cm^3, F(000) = 1100, μ = 3.601 mm^-1 and R = 0.0406; Crystal data for 3: monoclinic, space group C 2/c, a = 15.802(5), b = 14.242(4), c = 9.513(3) A, β = 97.695(5)°, V = 2121.8(10) A^3, Z = 4, Dc = 1.735 g/cm^3, F(000) = 1088 ,μ = 3.004 mm^-1 and R = 0.0273. In the three compounds, the Ln(Ⅲ) centers are eight-coordinated with antiprismatic geometry. The Ln(IN)3(H2O)2 unit connects mutually to form a one-dimensional double zigzag chain via isonicotinate oxygen bridging. The infinite chains are further linked by inter-chain hydrogen-bonding to form a three-dimensional supramolecular network. 展开更多
关键词 hydrothermal synthesis lanthanide coordination polymer ISONICOTINATE HYDROGEN-bondING
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Complementary method to locate atomic coordinates by combined searching method of structure-sensitive indexes based on bond valence method
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作者 宋振 刘小浪 +2 位作者 何丽珠 夏志国 刘泉林 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期344-348,共5页
Bond valence method illustrates the relation between valence and length of a particular bond type. This theory has been used to predict structure information, but the effect is very limited. In this paper, two indexes... Bond valence method illustrates the relation between valence and length of a particular bond type. This theory has been used to predict structure information, but the effect is very limited. In this paper, two indexes, i.e., global instability index(GII) and bond strain index(BSI), are adopted as a judgment of a search-match program for prediction. The results show that with GII and BSI combined as judgment, the predicted atom positions are very close to real ones. The mechanism and validity of this searching program are also discussed. The GII & BSI distribution contour map reveals that the predicted function is a reflection of exponential feature of bond valence formula. This combined searching method may be integrated with other structure-determination method, and may be helpful in refining and testifying light atom positions. 展开更多
关键词 bond valence method atomic coordinate prediction combined searching
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Diversity of supramolecular architecture of H_2salpn coordination compounds based on its flexibility
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作者 汤贝贝 何飞跃 李晖 《Journal of Beijing Institute of Technology》 EI CAS 2013年第3期417-422,共6页
Two complexes, [ Cu (salpn) ] · NH ( CH3 )2 ( 1 ) and [Ni ( salpn )·H20] ( 2 ) ( H2 salpn = N, N-bis(salicylidene)-propane-1,3-diamine) were characterized by IR, element analysis and single cry... Two complexes, [ Cu (salpn) ] · NH ( CH3 )2 ( 1 ) and [Ni ( salpn )·H20] ( 2 ) ( H2 salpn = N, N-bis(salicylidene)-propane-1,3-diamine) were characterized by IR, element analysis and single crystal X-ray diffraction analysis. Crystal data for complex 1 : monoclinic, P21/C, a = 1. 097 4×10^-7 cm, b=1.4806x10-7 cm, c=1.0315×10^-7 cm, β=94.43(3)°. The Cu (II) ion in complex 1 is four coordinated with distorted square planar coordination geometry. The crystal structure of com- plex 1 consists of [ Cu(salpn)] coordination complex and a guest molecule NH( CH3 )2 that can act as both H-bonding donor and acceptor and plays an important role in constructing supramolecular ar- chitecture. Crystal structure data for complex 2: orthorhombic, Pnma, a = 8. 676 3 ×10^-8 cm, b = 2. 414 5 ×10^-7 cm, c = 7. 538 8×10^-8 cm. The Ni(II) ion in complex 2 is five-coordinated with a but- terfly coordination geometry. The coordinated water molecule plays a key role in hydrogen-bonded networks. 展开更多
关键词 flexibility of n2 salpn butterfly coordination geometry hydrogen bonding π-π stacking
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AROMATIC BOND INCLUDING METALLIC ATOM IN COORDINATE COMPOUNDS AND SOME OF ITS PROPERTIES
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作者 Jing Jiang LIU Yun Ti CHENDepartment of Chemistry,Nankai University,Tianjin,300071R.Kent MURMANNDepartment of Chemistry,University of Missouri Columbia MO 65211,U.S.A 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第5期363-366,共4页
Aromatic bond including metallic atom (Ni) is investigated by EHMO calculation.The NMR spectra and the mechanism for hydrolysis are discussed on the ground of results of computation.
关键词 Ni PN AROMATIC bond INCLUDING METALLIC ATOM IN coordinATE COMPOUNDS AND SOME OF ITS PROPERTIES ITS
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Syntheses and Structures of Two New Coordination Polymers:[Cu(C_(14)H_9O_4)(C_(14)H_(10)O_4)(C_(12)H_(12)N_2)_2] and [Ag(C_(14)H_9O_4)(C_(13)H_(14)N_2)]·0.5H_2O
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作者 傅志勇 胡胜民 +3 位作者 杜文新 张建军 项生昌 吴新涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第2期176-182,共7页
关键词 铜配合物 银配合物 配位聚合物 氢键 合成 晶体结构 [Cu(C14H9O4)(C14H10O4)(C12H12N2)2] [Ag(C14H9O4)(C13H14N2)]·0.5H2O
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不同V型辅助配体构筑的两个镉配位聚合物的合成、结构和荧光性质
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作者 孙述文 王高峰 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第3期613-620,共8页
在溶剂热条件下,合成了2个基于V型辅助配体(bipmo、bppmo)的镉配位聚合物{[Cd(bipmo)(NDC)]·1.75H_(2)O}_n (1)和{[Cd(bppmo)(NDC)(H_(2)O)]·H_(2)O}_(n) (2),其中H_(2)NDC=2,6-萘二羧酸,bipmo=双(4-(1H-咪唑-1-基)苯基)甲酮,... 在溶剂热条件下,合成了2个基于V型辅助配体(bipmo、bppmo)的镉配位聚合物{[Cd(bipmo)(NDC)]·1.75H_(2)O}_n (1)和{[Cd(bppmo)(NDC)(H_(2)O)]·H_(2)O}_(n) (2),其中H_(2)NDC=2,6-萘二羧酸,bipmo=双(4-(1H-咪唑-1-基)苯基)甲酮,bppmo=双(4-(吡啶-4-基)苯基)甲酮。利用单晶X射线衍射、键价和分析、红外光谱和元素分析对其结构进行了表征。研究发现,配合物1具有二重互穿的{6~3}拓扑结构。配合物2同样是3-连接的{6~3}拓扑,却存在三重穿插结构。分析表明,V型配体对最终结构的形成有很大影响。此外,对配合物1和2的发光性质也进行了详细研究。 展开更多
关键词 键价和 配位聚合物 V型配体 拓扑结构 荧光
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国债管理:财政政策与货币政策协调配合的关键点
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作者 胡志浩 《学术前沿》 北大核心 2024年第3期65-73,共9页
国债兼具财政和金融功能,是财政政策与货币政策互动最为频繁活跃的领域,而货币政策的立场和操作也会直接影响赤字融资的来源与成本。因此,国债管理是两大政策协调配合的关键切入点。鉴于财政政策与货币政策配合的国际经验,针对我国政策... 国债兼具财政和金融功能,是财政政策与货币政策互动最为频繁活跃的领域,而货币政策的立场和操作也会直接影响赤字融资的来源与成本。因此,国债管理是两大政策协调配合的关键切入点。鉴于财政政策与货币政策配合的国际经验,针对我国政策协调配合中面临的挑战,我国应根据经济形势适时调整宏观政策调控机制;推动央行开展公开市场买卖国债;稳步推进国债市场的国际化建设;完善债务约束机制,科学设置债务上限;优化国库现金与央行流动性管理;积极发挥财政部在债务管理与国债市场建设中的主导作用,建立统一高效的政府债券市场;协同健全国债收益率曲线,共同推动曲线深入应用;进一步加强以国债为基础的金融市场流动性机制安排;在更高层面确立财政政策与货币政策的协调机制;保持两大政策部门更为畅通的信息交流。 展开更多
关键词 财政政策 货币政策 政策协调配合 国债管理
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