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Synthesis and Solid Phase Extraction Performance Study of NNAL-specific Molecularly Imprinted Polymers Using Dummy Templates 被引量:2
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作者 张志丹 郑赛晶 +3 位作者 杨俊 王维妙 刘百战 朱晓兰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第3期361-368,I0004,共9页
Dummy molecularly imprinted polymers (DMIPs) for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-(a... Dummy molecularly imprinted polymers (DMIPs) for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-(acetymethylamino)-1-(3-pyridyl)-butanol, 4- (methylamino)-1-(3-pyridyl)-1-butanol, and 1-(3-pyridyl)-1,4,-butanediol. The molecular recognition characteristics of the produced polymers were evaluated by X-ray photoelec- tron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). Interactions between NNAL and methacrylic acid should be cooperative hydrogen bonds while the ni- trogen atom of the pyridine ring and the oxygen atom of the nitroso group in NNAL are two of the hydrogen-bond acceptors. It was further demonstrated that DMIP synthesized by 4-(acetymethylamino)-1-(3-pyridyl)-butanol had the best binding performance by XPS and FT-IR. Then dummy molecularly imprinted solid phase extraction (DMISPE) was developed for the determination of the analyte using the hit polymer as the sorbing material. Under optimal conditions, the recovery of NNAL dissolved in standard solution reached 93%. And the investigated polymer exhibited much higher binding of NNAL when nicotine was acted as the competitive molecule. Also the proposed method was applied to the measurement of NNAL spiked in blank urine samples with recoveries ranging from 87.2% to 101.2%. 展开更多
关键词 Molecularly imprinted polymer Dummy template 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol Solid phase extraction
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Thermo-sensitive polymer nanospheres as a smart plugging agent for shale gas drilling operations 被引量:10
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作者 Wei-Ji Wang Zheng-Song Qiu +2 位作者 Han-Yi Zhong Wei-An Huang Wen-Hao Dai 《Petroleum Science》 SCIE CAS CSCD 2017年第1期116-125,共10页
Emulsifier-free poly(methyl methacrylate-styrene) [P(MMA-St)] nanospheres with an average particle size of 100 nm were synthesized in an isopropyl alcoholwater medium by a solvothermal method. Then, through radica... Emulsifier-free poly(methyl methacrylate-styrene) [P(MMA-St)] nanospheres with an average particle size of 100 nm were synthesized in an isopropyl alcoholwater medium by a solvothermal method. Then, through radical graft copolymerization of thermo-sensitive mono- mer N-isopropylacrylamide (NIPAm) and hydrophilic monomer acrylic acid (AA) onto the surface of P(MMA- St) nanospheres at 80 ℃, a series of thermo-sensitive polymer nanospheres, named SD-SEAL with different lower critical solution temperatures (LCST), were prepared by adjusting the mole ratio of NIPAm to AA. The products were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis, particle size distribution, and specific surface area analysis. The temperature-sensitive behavior was studied by light transmittance tests, while the sealing performance was investigated by pressure transmission tests with Lungmachi Formation shales. The experimental results showed that the synthesized nanoparticles are sensitive to temperature and had apparent LCST values which increased with an increase in hydrophilic monomer AA. When the temperature was higher than its LCST value, SD- SEAL played a dual role of physical plugging and chemical inhibition, slowed down pressure transmission, and reduced shale permeability remarkably. The plugged layer of shale was changed to being hydrophobic, which greatly improved the shale stability 展开更多
关键词 Nanoparticle plugging agent polymermicrospheres Thermo-sensitive polymer Wellborestability - Shale gas - Drilling fluid
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A New Luminescent Cd(Ⅱ) Coordination Polymer Constructed with 2-(Carboxymethoxy) benzoic Acid 被引量:5
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作者 王秀艳 李冠霆 +3 位作者 孙迪雅 张莹 刘东雪 徐占林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第12期1939-1944,1845,共7页
In this work, we synthesized a new Cd(Ⅱ) coordination polymer, [Cd(L)(cmb)H;O]· H;O(1), by using mixed 2-(carboxymethoxy)benzoic acid(H2 cmb) and typical chelating N-donor ligands 2-(2-fluoro-6-fluoro... In this work, we synthesized a new Cd(Ⅱ) coordination polymer, [Cd(L)(cmb)H;O]· H;O(1), by using mixed 2-(carboxymethoxy)benzoic acid(H2 cmb) and typical chelating N-donor ligands 2-(2-fluoro-6-fluorophenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline ligand(L). 1 crystallizes in monoclinic, space group P21/c with a = 17.6150(8), b = 9.7811(4), c = 18.1603(8) ?, β = 118.9150(10)o, V = 2738.9(2) ?;, Z = 4, C28 H20 CdF2 N4 O7, Mr = 674.88, Dc = 1.637 g/cm3, F(000) = 1352, μ(Mo Ka) = 0.865 mm–1, R = 0.0643 and w R = 0.1976. In 1, the cmb2– anions link neighboring Cd(Ⅱ) atoms in a bis-chelating mode, yielding a one-dimensional chain structure along the b axis. The L ligands are attached on one side of the chain through chelating the Cd(Ⅱ) atoms, and are stacked with those of an adjacent chain through π-π interactions to generate a one-dimensional double-chain structure. Furthermore, the one-dimensional double-chains are stacked by C–H???π interactions between the carbon atom of L ligand and the benzene ring of cmb2–ligand to give a layer structure. Moreover, the solid state luminescent property of 1 was also investigated at room temperature. 展开更多
关键词 crystal structure coordination polymer 2-(carboxymethoxy)benzoic acid
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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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Crystal Structure, Thermal Behavior and Luminescence of a New Copper Coordination Polymer Constructed with 4-(Carboxymethoxy)-benzoic Acid 被引量:3
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作者 WANG Xiu-Yan LI Guan-Ting +3 位作者 WANG Heng SONG Yu LIU Dong-Xue XU Zhan-Lin 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第4期629-634,共6页
A new Cu(Ⅱ) coordination polymer, [Cu(L1)(L2)](1), was synthesized under hydrothermal conditions(H_2L1 = 4-(carboxymethoxy)benzoic acid, L2 = 2-(4-fluorophenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline). Crystallograph... A new Cu(Ⅱ) coordination polymer, [Cu(L1)(L2)](1), was synthesized under hydrothermal conditions(H_2L1 = 4-(carboxymethoxy)benzoic acid, L2 = 2-(4-fluorophenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline). Crystallographic data for 1: triclinic, space group P1 with a = 9.750(5), b = 10.148(5), c = 12.869(5) ?, α = 104.904(5), β = 102.133(5), γ = 95.219(5)°, V = 1188.7(10) ?~3, Z = 2, C_(28)H_(17)FN_4O_5Cu, Mr = 572.01, D_c = 1.598 g/cm^3, F(000) = 582, μ(MoKa) = 0.977 mm^(-1), R = 0.0474 and w R = 0.1144. The TGA behaviors and luminescence of 1 have been studied in detail. The L1 dianions link neighboring Cu(Ⅱ) atoms in a bis-chelating mode, yielding a one-dimensional chain structure along the b axis. The L2 ligands are attached on one side of the chain through chelating the Cu(Ⅱ) atoms, and are stacked with those of an adjacent chain through π-π interactions, yielding a layer structure. Additionally, the N–H???O hydrogen bonds further stabilize the structure of 1. 展开更多
关键词 crystal structure COORDINATION polymer 4-(carboxymethoxy)benzoic acid copper(Ⅱ) LUMINESCENT property
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Synthesis, Structure and Photoluminescence of a New Cd(Ⅱ) Coordination Polymer Based on 4-(Carboxymethoxy)-benzoic Acid and 1,10-Phenanthroline Derivative 被引量:6
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作者 孔治国 张艳娜 刘福义 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第8期1175-1179,共5页
A new ID coordination polymer, [Cda(L1)2(L2)2].H2O (1, H2L1 = 4-(carboxy- methoxy)benzoic acid and L2 = 2-(4-fluorophenyl)-I H-imidazo[4,5-f][1,10]phenanthroline), has been hydrothermally synthesized and cha... A new ID coordination polymer, [Cda(L1)2(L2)2].H2O (1, H2L1 = 4-(carboxy- methoxy)benzoic acid and L2 = 2-(4-fluorophenyl)-I H-imidazo[4,5-f][1,10]phenanthroline), has been hydrothermally synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 9.985(5), b = 10.768(5), c = 12.512(5) A, a = 68.959(5), β = 80.354(5), γ = 79.663(5)°, V= 1227.4(10) A3, Z = 1, C56H36Cd2F2N8O11, Mr = 1259.73, Dc = 1.704 g/cm3, F(000) = 630, μ(MoKa) = 0.949 mm-1, R = 0.0261 and wR = 0.0655. The L1 anions link the neighboring Cd(II) atoms to form a 1D double chain structure. The L2 ligands are alternately located on both sides of the double chains. More interestingly, the lateral L2 ligands from adjacent double chains are paired to furnish strong π-π interactions, yielding a 2D supramolecular layer. N-H...O, O-H...N and O-H...O hydrogen bonds further stabilize the structure of 1. The luminescent property of 1 was studied in solid state at room temperature. 展开更多
关键词 crystal structure coordination polymer 4-(carboxymethoxy)benzoic acid2-(4-flnorophenyl)-lH-imidazo[4 5-f] [ 1 10]phenanthroline
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A New Cadmium(Ⅱ) Coordination Polymer Constructed by 2-(2-Chloro-6-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline and 1,2,3-Benzenecarboxylate: Synthesis, Structure and Luminescence 被引量:8
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作者 王秀艳 刘福义 +3 位作者 张艳娜 耿立荣 周昊 徐占林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第3期468-472,共5页
A new Cd(II) coordination polymer, namely, [Cd3(1,2,3-BTC)2(L)2]·2.25H2O (1, L = 2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-A][1,10]phenanthroline and 1,2,3-BTC = 1,2,3-ben- zenetricarboxylate), has bee... A new Cd(II) coordination polymer, namely, [Cd3(1,2,3-BTC)2(L)2]·2.25H2O (1, L = 2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-A][1,10]phenanthroline and 1,2,3-BTC = 1,2,3-ben- zenetricarboxylate), has been synthesized under hydrothermal conditions. The compound was characterized by single-crystal X-ray diffraction. It crystallizes in triclinic, space group Pī with α = 11.650(2), b = 12.240(2), c = 19.760(4) A, α = 72.01(3), β = 77.11(3), γ = 83.48(3)°, V = 2609.4(9) A3, Z = 2, C56H31Cd3Cl2F2N8O14.25, Mr = 1489.99, Dc = 1.896 g/cm3, F(000) = 1466, μ(MoKa) = 1.401 mm^-1, R = 0.0401 and wR = 0.1104. Compound 1 shows a 1D chain structure, and the neigh- boring 1D chains of 1 are joined together by π···π interactions to result in a 2D supramolecular layer. In addition, the luminescent property of 1 has been studied in the solid state at room temperature. 展开更多
关键词 coordination polymer crystal structure 1 2 3-benzenetricarboxylate 2-(2-chloro-6-fluorophenyl)-lH-imidazo [4 5-J] [1 10]phenanthroline
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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 WANG Xiu-Yan LI Cong +3 位作者 ZOU Chun-Kai KAN Ruo-Fei ZHANG Xiao-Xu XU Zhan-Lin 《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]p... 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) ?, α = 87.391(5), β = 82.925(5), γ = 81.841(5)o, V = 1204.2(10) ?3, Z = 2, C27H23FN4O5Co, Mr = 561.42, Dc = 1.548 g/cm3, 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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Synthesis, Crystal Structure and Property of a Series of Supramolecular Polymers Based on Novel 3,5-Dimethyl- 2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl)pyridine Ligand 被引量:3
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作者 李斌 范黎明 +2 位作者 孙忠 张伟 魏培海 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第12期1829-1836,共8页
Solvothermal reactions of 3,5-dimethyl-2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl) pyridine (L), 1,4-benzendicarboxylic acid (H2bdc), and transitional metal cations of M11 (M = Mn, Co, Cd) in the presence of oxa... Solvothermal reactions of 3,5-dimethyl-2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl) pyridine (L), 1,4-benzendicarboxylic acid (H2bdc), and transitional metal cations of M11 (M = Mn, Co, Cd) in the presence of oxalic acid (H2ox) afford three novel supramolecular polymers (CPs), namely, {[M2(ox)(L)2][bdc][M2(Hox)2(OH)(H2O)4]·3H2O}n (M = Mn for 1, Co for 2, Cd for 3). Single-crystal X-ray diffraction analysis reveals that complexes 1-3 are isostructural and the 3D supramolecular structure was connected through non-covalent interactions. With the help of H2ox, the L ligands cheated with center atoms forming a butterfly [M2(ox)(L)2]2+ building block. The bdc2- ligand linked with the unprecedented [M2(Hox)2(OH)2(H2O)4] units through strong O-H...O hydrogen bonds forming a zigzag chain, which are further connected through π-π interactions between L and bdc2- ligands to form a 3D supramolecular structure. Moreover, elemental analyses, IR, thermogravimetric, PXRD and luminescence have been investigated. 展开更多
关键词 3 5-dimethyl-2 6-bis(3-(pyrid-2-yl)-1 2 4-triazolyl)pyridine oxalic acid 1 4-benzendicarboxylic acid hydrogen bonds supramolecular polymers
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Synthesis, Structure and Characterization of a New Iron Coordination Polymer:[Fe(L)(trans-1,4-chdc)]_n 被引量:5
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作者 王秀艳 张艳娜 李丹 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第11期1589-1593,共5页
A novel Fe(II) coordination polymer [Fe(L)(trans-1,4-chdc)];~ has been hydrother- mally synthesized by using 1,4-cyclohexanedicarboxylic acid (1,4-H2chdc) and 2-(2-fluoro- phenyl)-lH-imidazo[4,5-f][1,10]phen... A novel Fe(II) coordination polymer [Fe(L)(trans-1,4-chdc)];~ has been hydrother- mally synthesized by using 1,4-cyclohexanedicarboxylic acid (1,4-H2chdc) and 2-(2-fluoro- phenyl)-lH-imidazo[4,5-f][1,10]phenanthroline (L). Crystallographic data: monoclinic, space group C2/c with a = 14.571(5), b = 32.389(6), c = 10.948(5)A, 18 = 115.186(5)°, V= 4676(3)A3, Z = 8, C27H21FFeN404, Mr = 540.33, De --- 1.535 g/cm3, F(000) = 2224, μ(MoKa) = 0.697 mmI, R = 0.0462 and wR = 0.1110. The two kinds of trans-l,4-chdc ligands link neighboring Fe(II) atoms to yield a two-dimensional layer structure. The π-π interactions between the L ligands of neighboring layers result in a three-dimensional supramolecular architecture. The IR and UV-vis spectra of the compound have been investigated in detail. 展开更多
关键词 coordination polymer crystal structure 2-(2-fluorophenyl)-lH-imidazo[4 5-f] [1 10]phenanthroline 1 4-cyclohexanedicarboxylie acid
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Helical Coordination Polymer with a 3-Fold Interpenetration Structure Based on 5-(Hydroxymethyl)isophthalic Acid 被引量:9
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作者 徐中轩 马钰璐 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第7期1193-1198,共6页
5-(Hydroxymethyl) isophthalic acid (H2HIA) as a novel organic ligand was prepared from 3,5-bis(methoxycarbonyl)benzoic acid by a two-step method. And then, a 3D helical coor- dination polymer with a 3-fold inter... 5-(Hydroxymethyl) isophthalic acid (H2HIA) as a novel organic ligand was prepared from 3,5-bis(methoxycarbonyl)benzoic acid by a two-step method. And then, a 3D helical coor- dination polymer with a 3-fold interpenetration structure, namely [Zn1/2(HIA)1/2(DPEE)1/2]n (1), was hydrothermally synthesized at 160 ℃, using H2HIA ligands to assemble with DPEE ligands and Zn2+ ions. Complex 1 crystalizes in orthorhombic system, space group Pnna, with a = 8.2118(5), b = 17.1698(7), c =14.9922(7) ?, V = 2113.82(18) ?3, μ = 1.194 mm-1, Z = 4 and S = 0.967. Moreover, some physical characteristics of complex 1, such as powder X-ray diffraction (PXRD), thermogravimetry analyses (TGA) and photoluminescent properties, were also investigated. 展开更多
关键词 5-(hydroxymethyl) isophthalic acid helical coordination polymer 3-fold interpenetration structure
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Synthesis and Crystal Structure of a New Lead Coordination Polymer: [Pb(L)(1,4-ndc)] 被引量:5
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作者 孔治国 马晓媛 +1 位作者 徐占林 王秀艳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第11期1749-1752,共4页
The title coordination polymer, [Pb(L)(1,4-ndc)] 1 (L = 2-(4-fluorophenyl)-1Himidazo[4,5f1,10]phenanthroline, 1,4-ndc = naphthalene-1,4-dicarboxylic acid), has been obtained by using hydrothermal synthesis and... The title coordination polymer, [Pb(L)(1,4-ndc)] 1 (L = 2-(4-fluorophenyl)-1Himidazo[4,5f1,10]phenanthroline, 1,4-ndc = naphthalene-1,4-dicarboxylic acid), has been obtained by using hydrothermal synthesis and characterized by elemental analysis, IR and singlecrystal X-ray diffraction. It crystallizes in monoclinic, space group P21/c with a = 10.1043(11), b = 14.3162(15), c = 17.6061(18), β = 95.3990(10)°, V = 2535.5(5)3, Z = 4, C31H17FN4O4Pb, Mr = 735.68, Dc = 1.927 g/cm3, F(000) = 1416, μ(MoKa) = 6.709 mm-1, R = 0.0201 and wR = 0.0489. The 1,4-ndc dianions link neighboring Pb(II) atoms in a bis-chelating mode, yielding a one-dimensional chain structure along the c axis. The C-H···π interactions between the carbon atom of L ligand and the benzene ring of 1,4-ndc lead the one-dimensional chains to form a two-dimensional supramolecular layer. The π-π interactions between L ligand and 1,4-ndc ligand make the two-dimensional layers generate a three-dimensional supramolecular architecture. Additionally, the N-H···O hydrogen bonds further stabilize the structure of 1. 展开更多
关键词 lead complex crystal structure coordination polymer 2-(4-fluorophenyl)-lH-imidazo [4 5-f] [1 10]phenanthroline
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Low-Cost 4-20 mA Loop Calibrator
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作者 Joel Arumun Emmanuel Eronu 《Journal of Flow Control, Measurement & Visualization》 2023年第3期49-63,共15页
Instrument calibration is vital to a successful control system because signal inputs to the system controllers come from such instruments. This paper presents a method for actualizing a standard low-cost loop calibrat... Instrument calibration is vital to a successful control system because signal inputs to the system controllers come from such instruments. This paper presents a method for actualizing a standard low-cost loop calibrator for the famous 4-20 mA electrical signaling scheme. The loop calibrator generates a linear current signal from 4 to 20 mA over a 250 ? typical process instrument load for calibration. The realization of the loop calibrator relies on a voltage-to-current converter to build a constant current source. The voltage controlled constant current source is built from discrete components and an op-amp to keep the cost low. Results from simulations and the prototype demonstrate the performance of the 4-20 mA loop calibrator which utilizes a greatly reduced number of components. The cost of these components is approximately 34% of the least expensive calibrator sampled, though other production costs are not included. This conclusion reinforces the fact that loop calibrators can be cheaper. 展开更多
关键词 INSTRUMENTS CALIBRATION 4-20 mA Standard loop Calibrator
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SYNTHESIS AND CHARACTERIZATION OF A NOVEL POLYMER ELECTROLYTE BASED ON ACRYLONITRILE/N-[4-(AMINOSULFONYL)PHENYL]ACRYLAMIDE COPOLYMERS 被引量:1
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作者 Ang-ran Wang 包永忠 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第1期129-135,共7页
Acrylonitrile/N-[4-(aminosulfonyl)phenyl]acrylamide (AN/ASPAA) copolymers were synthesized and used as a host of lithium ion conducting electrolytes. The composition, molecular weight and molecular weight distribu... Acrylonitrile/N-[4-(aminosulfonyl)phenyl]acrylamide (AN/ASPAA) copolymers were synthesized and used as a host of lithium ion conducting electrolytes. The composition, molecular weight and molecular weight distribution of AN/ASPAA copolymers were determined, and the influence of copolymer composition on the glass temperature of AN/ASPAA copolymers and the ion conductivity of electrolytes were investigated. The molecular weights of AN/ASPAA copolymers were lower than those of AN and ASPAA homopolymers due to the cross-termination reaction. The glass temperatures of AN/ASPAA copolymers increased as the molar fraction of ASPAA units in copolymers increased. The lithium ion conductivities of the polymer electrolytes increased initially as the molar fraction of ASPAA units in copolymers increased, and a maximum conductivity was achieved when the molar fraction of ASPAA in the copolymer was 16.8%. 展开更多
关键词 ACRYLONITRILE N-[4-(aminosulfonyl)phenyl]acrylamide COpolymerIZATION COMPOSITION polymer electrolyte
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Synthesis,Crystal Structure and Magnetic Properties of a Cobalt(Ⅱ)Coordination Polymer with4,4'-(Propane-2,2-diyl)dibenzoate and4,4'-Bis(1-imidazolyl)biphenyl 被引量:2
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作者 刘光祥 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第10期1579-1585,共7页
A novel coordination polymer, {[Co(CBA)(BIMB)0.5]'H20}n (1, H2CBA = 4,4'- (propane-2,2-diyl)dibenzoic acid, and BIMB = 4,4'-bis(1-imidazolyl)biphenyl), has been hydro- thermally prepared and characterized... A novel coordination polymer, {[Co(CBA)(BIMB)0.5]'H20}n (1, H2CBA = 4,4'- (propane-2,2-diyl)dibenzoic acid, and BIMB = 4,4'-bis(1-imidazolyl)biphenyl), has been hydro- thermally prepared and characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. The crystal is of monoclinic system, space group P2/c with a = 14.909(3), b = 7.1963(15), c = 24.592(5) A, β = 104.312(2), V = 2556.5(9) A3, C26H23N2OsCo, Mr = 502.39, Dc = 1.305 g/cm3, F(000) = 1040,μ = 0.708 mm-1 and Z = 4. The final R= 0.0580 and wR = 0.1605 for 3228 observed reflections (1 〉 2a(I)). Single-crystal structure analysis shows that complex 1 exhibits a three-dimensional 2-fold interpenetrating pillared helical-layer open framework of a-Po topology based upon binuclear paddlewheel units. Moreover, its magnetic properties have also been investigated. 展开更多
关键词 cobalt coordination polymer crystal structure 4 4'-(propane-2 2-diyl)dibenzoic acid magnetism
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Synthesis, Crystal Structure and Properties of a Chiral 3D Supramolecular Coordination Polymer [Co(HL)·(DMF)]_n from 5-(Imidazol-1-ylmethyl)isophthalic Acid 被引量:1
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作者 李付安 徐伏 +1 位作者 杨维春 李松田 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第9期1438-1444,共7页
A chiral supramolecular coordination polymer, [Co(HL)·(DMF)]n(1), with helical chains from a flexible ligand 5-(imidazol-1-ylmethyl)isophthalic acid(H2L) has been obtained under hydrothermal conditions ... A chiral supramolecular coordination polymer, [Co(HL)·(DMF)]n(1), with helical chains from a flexible ligand 5-(imidazol-1-ylmethyl)isophthalic acid(H2L) has been obtained under hydrothermal conditions and characterized by elemental analysis, powder X-ray diffraction(PXRD), IR, Uv/vis spectra, thermal gravimetric analyses(TGA) and also by single-crystal X-ray diffraction. It crystallizes in hexagonal, space group P6522 with a = 8.8109(3), b = 8.8109(3), c = 71.771(3) , γ = 120°, V = 4825.3(3) -3, Z = 6, Mr = 695.55, Dc = 1.436 g/cm-3, Rint = 0.0684, F(000) = 2166, the final R = 0.0923 and w R = 0.2697 for 3056 observed reflections(I 2σ(I)). The title coordination polymer 1 shows a chiral layered structure based on right-handed helix chains. Such layers are associated together through hydrogen-bonding interactions to form a 3D supramolecular framework. 展开更多
关键词 COBALT 5-(imidazol-1-ylmethyl)isophthalic acid PXRD chiral coordination polymer
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A Novel Gd Coordination Polymer Based on 2-(Pyridin-3-yl)-1H-imidazole-4,5-dicarboxylate: Synthesis, Structure and Dielectric Properties 被引量:1
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作者 黄登登 陈立庄 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第3期361-366,共6页
A new Gd coordination polymer based on 2-(pyridin-3-yl)-lH-imidazole-4,5-dicar- boxylate, formulated as {[Gd2(HPyIDC)2(H2O)5]·(bpy)·(NO3)2·3H2O}n (1, bpy = 4,4'-bipyridine) has been synthes... A new Gd coordination polymer based on 2-(pyridin-3-yl)-lH-imidazole-4,5-dicar- boxylate, formulated as {[Gd2(HPyIDC)2(H2O)5]·(bpy)·(NO3)2·3H2O}n (1, bpy = 4,4'-bipyridine) has been synthesized under hydrothermal conditions. The compound crystallizes in triclinic, space group Pi with a = 11.451(2), b = 11.596(2), c = 15.7333(3) A, β = 79.47(3)°, Z = 2, V= 1948.6(7) A^3, C30H34Gd2N10O22, Dc = 2.047 g/cm^3, Mr= 1201.17, 2(MoKa) = 0.71073 A,μ = 3.477 mml, F(000) = 1176, the final R = 0.0554 and wR = 0.1181. Polymer 1 is a 2D network built up from 4-connected HPylDC2- anion and 4-connected Gd ions. Dielectric constant of complex 1 was measured at different frequencies with temperature variation. 展开更多
关键词 2D network GD HYDROTHERMAL 2-(pyridin-3-yl)-lH-imidazole-4 5-dicarboxylate coordination polymer
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A One-dimensional Pseudo-helical Coordination Polymer with 4,4′-(Hexafluoroisopropylidene)bis(benzoic acid) 被引量:1
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作者 赵文娜 韩磊 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第3期343-347,共5页
The title complex [Zn2(hfipbb)2(2,2′-bpy)2], 1 has been hydrothermally synthesized from Zn(NO3)2·6H2O, 4,4′-(hexafluoroisopropylidene)bis(benzoic acid) and 2,2′-bipyridine. Singlecrystal X-ray analys... The title complex [Zn2(hfipbb)2(2,2′-bpy)2], 1 has been hydrothermally synthesized from Zn(NO3)2·6H2O, 4,4′-(hexafluoroisopropylidene)bis(benzoic acid) and 2,2′-bipyridine. Singlecrystal X-ray analysis reveals that 1 presents a one-dimensional coordination polymer with pseudo-helical chain structure. Two Zn(Ⅱ) atoms in an unsymmetrical unit of 1 adopt distorted octahedral and square-pyramidal coordination geometries, respectively. The packing of parallel chains gives a three-dimensional supramolecular network supported by π-π stacking interactions. Crystal data: C54H32F12N4O8Zn2, Mr = 1223.58, monoclinic, space group P2 1/c, a = 27.557(6), b = 16.751(3), c = 11.350(2) A, β= 99.21(3)°, V= 5171.5(18) A^3, Z= 4, Dc = 1.572 g/cm^3, F(000) = 2464, μ= 1.030 mm^-1, the final R = 0.0552 and wR = 0.1070 for 6631 observed reflections (I〉 2σ(I)). 展开更多
关键词 coordination polymers crystal structures pseudo-helical chains 4 4′-(hexafluoroisopropylidene)bis(benzoic acid)
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A Co(Ⅱ) Coordinated Polymer with 2-Fold Interpenetration 3D Architecture Based on 5-(Imidazol-1-ylmethyl)isophthalate: Hydrothermal Synthesis, Crystal Structure and Properties 被引量:2
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作者 LI Fu-An ZHAO Xiao-Jun +1 位作者 YANG Wei-Chun LI Song-Tian 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第8期1281-1287,共7页
One cobalt coordinated polymer with 2-fold parallel interpenetration 3D architecture based on flexible 5-(imidazol-1-ylmethyl)isophthalate (L2-) as a main ligand and 4,4'-bipyridine (bpy) as a nitrogen-containi... One cobalt coordinated polymer with 2-fold parallel interpenetration 3D architecture based on flexible 5-(imidazol-1-ylmethyl)isophthalate (L2-) as a main ligand and 4,4'-bipyridine (bpy) as a nitrogen-containing ancillary ligand, {[CoL(bpy)0.5(H2O)3]2}n (1), has been obtained under hydrothermal conditions and characterized by elemental analysis, powder X-ray diffraction (PXRD), IR spectra, Uv/vis spectra, thermal gravimetric analyses (TGA) and single-crystal X-ray diffraction. It crystallizes in monoclinic, space group C2/c with a = 26.323(4), b = 14.696(2), c = 26.630(4) A, β= 157.747(4)°, V = 3901.2(1) A3, Z = 8, Mr= 435.27, Dc = 1.480 g/cm3, /t= 0.923 mm^-1, Rint = 0.0900, F(000) = 1792, the final R= 0.0722 and wR = 0.0946 for 3641 observed reflections (I 〉 2tr(/)). Complex 1 exhibits a two-fold interpenetration 3D framework. As a single net of the 2-fold interpenetration structure, the L2- anion of complex 1, as a bridging ligand, connects the Co(Ⅱ) ion to form two-dimensional layers (Co3L3)n which are further linked to build a three-dimensional framework by bpy ligand. 展开更多
关键词 cobalt 5-(imidazol-l-ylmethyl)isophthalic acid PXRD coordinated polymer
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A One-dimensional Cd(Ⅱ)Coordination Polymer Constructed from 1,4-Benzene-dicarboxylic Acid and 3-(2,6-Di(pyrazin-2-yl)pyridin-4-yl)-1H-indole:Synthesis,Structure and Photoluminescence 被引量:2
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作者 谢玲 卢丽萍 朱苗力 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第10期1606-1614,共9页
A new coordination polymer {[Cd(C_(21)H_(14)N_6)(C_8H_4O_4)]·H_2O}_n(1) was synthesized by an elaborate design via the reaction of 3-(2,6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole(bppi),1,4-benzene-... A new coordination polymer {[Cd(C_(21)H_(14)N_6)(C_8H_4O_4)]·H_2O}_n(1) was synthesized by an elaborate design via the reaction of 3-(2,6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole(bppi),1,4-benzene-dicarboxylic acid(H2bdc) and cadmium(Ⅱ) nitrate in CH_3OH/H_2O mixed solvents. Complex 1 crystallizes in orthorhombic,space group Ccca with a = 20.012(4),b = 31.881(6),c = 19.808(4) ?,V = 12638(4) ?~3,Z = 16,C_(29)H_(20)CdN_6O_5,M_r = 644.91,D_c = 1.356 g·cm^(-3),μ = 0.735 mm^(-1),F(000) = 5184,GOOF = 1.046,the final R = 0.0405 and wR = 0.1063 for 6870 observed reflections(I 〉 2σ(I)). The Cd(Ⅱ) centre is hepta-coordinated by three N and four O atoms from one bppi terminal ligand and two bdc2– ligands,respectively,displaying a capped trigonal prism geometry. Structure extension gives coordination polymeric chains,in which the bdc2– linkers connect Cd(Ⅱ) cations into a one-dimensional(1D) coordination polymer along the c axis,giving zigzag chains with the Cd···Cd separation of 11.178(1) ?. The adjacent bppi terminal ligands in the chains are anti-periplanar conformation. The three-dimensional(3D) structure is stabilized by π···π stacking and hydrogen-bonding interactions to form a supramolecular self-penetrating network with 1D channels. In 1,there are voids 2999.7 ?~3 with 23.7% of per unit cell volume. Thermal analysis indicates that the framework of 1 is stable until 651 K and the photoluminescence of 1 in the solid shows very weak fluorescence at 382 and 560 nm upon excitation at 310 nm. 展开更多
关键词 1 4-benzenedicarboxylic acid 3-(2 6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole one-dimensional cadmium(Ⅱ) coordination polymer π···π stacking interactions photoluminescence
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