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Construction of Teaching Case Base of Anti-Seismic Design of Building Structure
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作者 Huina Li 《Journal of Architectural Research and Development》 2023年第3期13-18,共6页
Anti-Seismic Design of Building Structures is an important course in civil engineering majors,and it is also a course that pays equal attention to theory and practice.Therefore,by establishing a case base for Anti-Sei... Anti-Seismic Design of Building Structures is an important course in civil engineering majors,and it is also a course that pays equal attention to theory and practice.Therefore,by establishing a case base for Anti-Seismic Design of Building Structures,the obscure theoretical knowledge can be taught to students in the form of examples,and the knowledge becomes intuitive.In this way,the students’understanding of anti-seismic design theory and the efficiency of teaching can be improved,and the students’interest in learning can be stimulated. 展开更多
关键词 Building structure Anti-seismic design Case base
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Syntheses,Crystal Structures and Kinetic Mechanisms of Thermal Decomposition of Rare Earth Complexes with Schiff Base Derived from o-Vanillin and p-Toluidine 被引量:5
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作者 赵国良 冯云龙 温一航 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期268-275,共8页
Three complexes, [Pr(NO3)3(HL)2] (1), [Nd(NO3)3(HL)2] (2) and [Er(NO3)3(HL)2] ·0.5H2O (3), were synthesized from the reaction of a Schiff base ligand 2-[ (4-methylphenylimino)methyl ]-6-methox... Three complexes, [Pr(NO3)3(HL)2] (1), [Nd(NO3)3(HL)2] (2) and [Er(NO3)3(HL)2] ·0.5H2O (3), were synthesized from the reaction of a Schiff base ligand 2-[ (4-methylphenylimino)methyl ]-6-methoxyphenol (C15 H15 NO2, HL) with Ln(NO3)3·6H2O (Ln = Pr, Nd, Er). Characterization by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, ^1H NMR and thermal analysis shows the title complexes are neutral molecules where the central Ln( Ⅲ) ion is ten-coordinated in biapical anti-hexahedron prism geometry, with four oxygen atoms of the phenolic hydroxy and methoxy groups in the two bidentate Schiff base ligands and six oxygen atoms provided by the three bidentate NO3 - anions. Additionally, the kinetic mechanism of thermal decomposition of complex 3 was determined with a TG-DTG curves by both integral and differential methods. The functions of thermal decomposition reaction mechanism and the equation of kinetic compensation effect were obtained. 展开更多
关键词 O-VANILLIN P-TOLUIDINE Schiff base crystal structure kinetic mechanism of thermal decomposition rare earths
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Syntheses, Crystal Structures and Antibacterial Activities of Schiff Base Ligand and Its Nickel(Ⅱ) Complex 被引量:5
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作者 李斐然 张欣 +2 位作者 王东东 薛志娜 马莺珂 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第9期1367-1374,共8页
A complex [NIL2] was synthesized, in which L, or to be exact, a Schiff base ligand (HL), was derived from the condensation of 1-phenyl-3-methyl-4-phenylacetyl-5-pyrazolone (PMPAP) with L-phenylalanine methyl ester... A complex [NIL2] was synthesized, in which L, or to be exact, a Schiff base ligand (HL), was derived from the condensation of 1-phenyl-3-methyl-4-phenylacetyl-5-pyrazolone (PMPAP) with L-phenylalanine methyl ester. They were characterized by IR and single-crystal X-ray diffraction. Green block crystals of both ligand and its complex were grown at room temperature. The ligand, which consists of two individual fragments, crystalizes in the P1 space group (a = 5.6268(5), b = 10.6892(11) and c = 19.4869(18) A). The complex crystalizes in the P21 space group (a -- 21.4076(18), b = 9.4792(8) and c = 25.287(2) A), which consists of a nickel six-coordinated compound. Every fragment is a distorted octahedron with four oxygen and two nitrogen atoms. The Schiff base ligand (HL) and its complex have been tested in vitro to evaluate their antibacterial activity against bacteria Escherichia Coli and Bacillus subtilis. It is found that the complex has higher activity than the corresponding free Schiff base ligand (HL) against the same bacterial. 展开更多
关键词 Schiff base COMPLEX crystal structure antibacterial activity
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Synthesis, Crystal Structure and Cytotoxic Activity of a Novel Nickel(II) Complex with Schiff Base Derived from Salicylhydrazide 被引量:4
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作者 仇晓阳 罗志刚 +1 位作者 刘伟生 朱海亮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第6期707-711,共5页
A novel Schiff base complex with π-conjugated system, [Ni(L1)2(py)2] 1 (L1 =(E)-N′-(2,4-dichlorobenzylidene)-2-oxidobenzohydraizide), was synthesized and characterized by elemental analysis and single-crys... A novel Schiff base complex with π-conjugated system, [Ni(L1)2(py)2] 1 (L1 =(E)-N′-(2,4-dichlorobenzylidene)-2-oxidobenzohydraizide), was synthesized and characterized by elemental analysis and single-crystal X-ray determination. Complex 1 crystallizes in the monoclinic system, space group P21/n with a = 12.8286(10), b = 16.3573(13), c = 19.0206(14) A, β = 108.2920(10)°, V = 3789.6(5)A^3, Z = 4, Mr = 833.17, Dc = 1.460 g/cm^3,/t = 0.843 mm^-1, F(000) = 1704, the final R = 0.0537 and wR = 0.0640 for 3836 observed reflections with I 〉 2σ(I). In the molecular structure of 1, the Ni^Ⅱ atoms are six-coordinated by two N and two O atoms from two Schiff base ligands (LI) and two N atoms from two pyridine solvent molecules to form a distorted octahedral geometry. The cytotoxic activities of complex 1 have been experimentally studied against a human HeLa cell in vitro. 展开更多
关键词 Sehiff base Nin complex crystal structure cytotoxic activities
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Synthesis and Crystal Structure of a Zinc(II) Complex Salt with the Schiff Base of Picolinaldehyde N-oxide and Semicarbazone 被引量:5
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作者 YU Qing ZHU Li-Gang BIAN He-Dong DENG Ji-Hua YANG Xiao-E GUO Gui-Quan LIANG Hong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第11期1271-1275,共5页
The title zinc(Ⅱ) complex salt [Zn(H2O)6](ClO4)2-(PNOS)4, where PNOS is derived from picolinaldehyde N-oxide with semicarbazone, has been prepared and structurally characterized by X-ray single-crystal analys... The title zinc(Ⅱ) complex salt [Zn(H2O)6](ClO4)2-(PNOS)4, where PNOS is derived from picolinaldehyde N-oxide with semicarbazone, has been prepared and structurally characterized by X-ray single-crystal analysis. It crystallizes in triclinic, space group PI with a = 7.529(3), b = 10.206(4), c = 14.678(6)A, a = 86.293(6), β= 87.686(7), γ= 81.382(6)°, C28H44Cl2N16O22Zn, Mr = 1093.06, V = 1112.3(8) ,A^3 Z = 1, Dc = 1.632 g/cm^3, S = 1.089, μ(MoKa) = 0.773 mm^-1, F(000) = 564, the final R = 0.0438 and wR = 0.1076 for 3888 independent reflections with Rint = 0.0224. The crystal structure possesses a [Zn(H2O)6]^2+ cation, two ClO4^- anions and four PNOSs. In the crystal structure, Zn^2+ cation is located at the symcenter and coordinated by six water molecules. In [Zn(H2O)6]^2+, an elongate octahedral complex cation, the average Zn-O bond length is 2.087(2) A. There exist a lot of H bonds in the structure, linking the cation [Zn(H2O)6]^2+, anion ClO4^- and PNOS to form a 3D network. 展开更多
关键词 zinc(Ⅱ) complex salt picolinaldehyde N-oxide SEMICARBAZONE crystal structure Schiff base
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Synthesis and Crystal Structure of a New Three-dimensional Supramolecule of Copper(Ⅱ) Schiff Base Complex 被引量:3
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作者 LI Chun-Hong WANG Qiang +1 位作者 XU Yan-Qing HU Chang-Wen 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第2期187-190,共4页
A new three-dimensional supramolecule composed of copper-Schiff base complex, [Cu(naphdien)]Cl·H2O, where naphdien is Schiff base of 2-hydroxy-1-naphthaldehyde and diethylenetriamine, has been synthesized and d... A new three-dimensional supramolecule composed of copper-Schiff base complex, [Cu(naphdien)]Cl·H2O, where naphdien is Schiff base of 2-hydroxy-1-naphthaldehyde and diethylenetriamine, has been synthesized and determined by single-crystal X-ray diffraction. It belongs to the monoclinic system, space group P21/c, with a = 7.3490(15), b = 7.0847(16), c = 30.845(3)A, β= 95.33(3)°, V = 1599.0(5)A3, Z = 4, C15 H20ClCuN3O2, Mr = 373.33, De = 1.551 g/cm3, μ = 1.543 mm^-1, F(000) = 772, R = 0.0536 and wR = 0.0927 for 2788 unique reflections with 1659 observed ones (I 〉2σ(I)). In the crystal structure, mononuclear units [Cu(naphdien)]Cl·H2O are linked into a two-dimensional framework via strong hydrogen bonds, and extended into a three-dimensional supramolecular structure through π-π stacking interactions. 展开更多
关键词 COPPER crystal structure Schiff base hydrogen bonds
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Syntheses, Characterizations, Crystal Structures and Antibacterial Activities of Two Zinc(II) Complexes with a Schiff Base Derived from o-Vanillin and p-Toluidine 被引量:3
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作者 余玉叶 赵国良 温一航 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1395-1402,共8页
Two new zinc(Ⅱ) complexes, [Zn2L2Ch].2[ZnL(CH3OH)Cl2] 1 and [ZnL2(NO3)2] 2, were synthesized by reacting ZnX2.nH2O (X = Cl^-, NO3^-) and a Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-methoxyphenol ... Two new zinc(Ⅱ) complexes, [Zn2L2Ch].2[ZnL(CH3OH)Cl2] 1 and [ZnL2(NO3)2] 2, were synthesized by reacting ZnX2.nH2O (X = Cl^-, NO3^-) and a Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-methoxyphenol (C15HIsNO2, L) which was obtained by the condensation of o-vanillin (2-hydroxy-3-methoxybenzaldehyde) with p-toluidine. Both 1 and 2 were characterized by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, IH-NMR spectra and thermogravimetrie analysis. The Schiff base ligand and its zinc(Ⅱ) complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia Coli, Staphylococcus aureus and Bacillus Subtilis. The results show that these complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria. 展开更多
关键词 O-VANILLIN P-TOLUIDINE Schiff base zinc(Ⅱ) complex crystal structure antibacterial activities
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Synthesis and Crystal Structure of a Novel Binuclear Cu(Ⅱ) Complex with Tetradentate Schiff-base Ligand 被引量:3
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作者 ZHAO Hai-Yan QIU Xiao-Hang +1 位作者 TONG Xiao-Lan SHEN Pan-Wen 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第9期1095-1099,共5页
A novel binuclear complex ([Cu^2(μ2-shed)(hshed)].(CIO4),H2O, h2shed = N-salicylidene-N'-(2-hydroxyethyl)ethylenediamine) has been synthesized and structurally characterized by X-ray diffraction analysis. ... A novel binuclear complex ([Cu^2(μ2-shed)(hshed)].(CIO4),H2O, h2shed = N-salicylidene-N'-(2-hydroxyethyl)ethylenediamine) has been synthesized and structurally characterized by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/c with a = 12.511(10), b = 15.750(12), c = 14.281 (12) A, β = 100.564(14)°, C22H31CIN4O9Cu2, Mr = 658.04, V = 2766(4) A^3, Z = 4, Dc = 1.580 g/cm^3,μ(MoKα = 1.689 mm^-1, F(000) = 1352, the final R = 0.0528 and wR = 0.1433 for 4880 independent reflections with Rint = 0.0577. The complex is a binuclear copper compound, and two Cu(Ⅱ) ions in the binuclear cation are in different coordination environments. The Cu(1) ion adopts a distorted square pyramidal geometry (x = 0.22) with four donor atoms (N2O2) of the ligand in the basal plane, and one hydroxyl oxygen atom with protonated form occupying the apical position. The Cu(2) ion assumes the geometry of a distorted square plane with four donor atoms (N2O2) of the ligand. The Cu...Cu separation is 3.103 A,. In addition, N-H…O and C-H…O intermolecular hydrogen bonding interactions link these binuclear cations into a quasi one-dimensional chain along the a axis. 展开更多
关键词 Schiff base copper (Ⅱ) complex crystal structure hydrogen bonds
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Syntheses, Crystal Structures and Antibacterial Activities of Two Heterocyclic Schiff Base Compounds 被引量:2
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作者 杨高山 刘崇波 +3 位作者 李恒农 陈园 黄得和 温辉梁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第4期528-534,共7页
Two heterocyclic Schiff bases were synthesized via the condensation reactions of primary amines with carbonyl compounds. 2-[(4-pyridylmethylene)-amino] phenol (compound 1) was synthesized by the interaction of 4-p... Two heterocyclic Schiff bases were synthesized via the condensation reactions of primary amines with carbonyl compounds. 2-[(4-pyridylmethylene)-amino] phenol (compound 1) was synthesized by the interaction of 4-pyridinecarboxaldehyde with o-aminophenol in ethanol solvent; N,N'-bis(3-(furan-2-yl)allylidene)benzene-1,4-diamin (compound 2) was synthesized by the interaction of 3-(2-furyl)acrolein with p-phenylenediamine in ethanol medium. The compounds were characterized by elemental analysis, IR, MS and single-crystal X-ray diffraction. Compound 1 (C12H10N2O) crystallizes in the monoclinic system, space group P21/c with α = 7.0771(7), b = 7.2820(7), c = 19.849(2), b = 96.3390(10)°, V = 1016.66(17) ?3, Z = 4, Mr = 198.22, Dc = 1.295 g/cm3, F(000) = 416, GOOF = 1.060, m = 0.085 mm-1, the final R = 0.0371 and wR = 0.0929 for 1497 observed reflections with I 〉 2σ(I). Compound 2 (C20H16N2O2) crystallizes in the orthorhombic system, space group Fdd2 with α = 26.344(15), b = 48.50(3), c = 5.293(3), V = 6764(7) ?3, Z = 16, Mr = 316.35, Dc = 1.243 g/cm3, F(000) = 2656, GOOF = 1.043, m = 0.081 mm-1, the final R = 0.0526 and wR = 0.1267 for 2059 observed reflections with I 〉 2σ(I). 1 and 2 molecules are connected through hydrogen bonds to generate a 2D network and a 1D chain structure, respectively. The preliminary antibacterial activity results showed that the title compounds display excellent antibacterial activities to Escherichia coli, Staphylococcus aureus and Bacillus subtilis. 展开更多
关键词 HETEROCYCLIC Schiff bases synthesis crystal structure antibacterial activity
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Synthesis, Structure and Antibacterial Activities of 4-BBTS Schiff Base and Its Complexes 被引量:2
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作者 LI Pei-Fan LIU Bin WANG Jin-Ling 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第2期224-228,共5页
4-Bromobenzaldehyde thiosemicarbazone Schiff base (4-BBTS) and its Cu(Ⅱ), Zn(Ⅱ), Co(Ⅱ) and Ni(Ⅱ) complexes were synthesized and characterized by elemental analysis, UV, IR, MS, ^1H NMR, and molar conduct... 4-Bromobenzaldehyde thiosemicarbazone Schiff base (4-BBTS) and its Cu(Ⅱ), Zn(Ⅱ), Co(Ⅱ) and Ni(Ⅱ) complexes were synthesized and characterized by elemental analysis, UV, IR, MS, ^1H NMR, and molar conductivity. Using disc diffusion method, the antibacterial activity tests were conducted. The results revealed that the ligand as well as all the complexes exhibits good antibacterial activities against E. Coli. and S. Aureus. Moreover, Cu(Ⅱ) complex shows the best antibacterial activity, which provides beneficial reference for studying the relationship between the structures and performances. 展开更多
关键词 4-BBTS Schiff base SYNTHESIS structure antibacterial activity
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Synthesis,Crystal Structure and Quantum Chemical Investigation of Bis-Schiff Base Compounds Derived from2-phenyl-1,2,3-triazole-4-carboxaldehyde with Diamine 被引量:2
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作者 XIE Ling LIU Gang WANG Yan WANG Ji-De CHEN Jun-Feng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第5期616-621,共6页
Two new schiff base N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene)-1,3-propanediamine (1) and N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene) -1,4-butanediamine (2) were synthesized by condensat... Two new schiff base N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene)-1,3-propanediamine (1) and N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene) -1,4-butanediamine (2) were synthesized by condensation of 2-phenyl-1,2,3-triazole-4-carboxaldehyde with diamine, and characterized by elemental analysis, IR, IH NMR and MS spectra. Their crystal structures were determined by X-ray single crystal diffraction. Both crystals belong to the monoclinic system, space group P21/c. For compound 1(C21H20N8, Mr=384.45): a = 16.314(3), b =5.7168(11), c = 21.316(4) A, β = 105.3(2)°, Z = 4, V = 1917.6(7) A^3, De =1.332 g/cm^3, F(000) = 808,μ = 0.086 mm 1, R = 0.0533 and wR = 0.1460; for compound 2 (C22H22N8, Mr=398.48): a = 8.6156(17), b = 5.2964(11), c = 22.665(5)A, β = 100.54(3)°, Z = 2, V = 1016.8(4) A^3, De= 1.302 g/cm^3, F (000) = 420, μ = 0.083 mm^-1, R = 0.0373 and wR = 0.1155. Based on the crystal data, quantum chemistry calculation was performed on the two title compounds by means of Gaussian 98 program. The molecular orbital energies and atomic net charges population were obtained. Furthermore, we antilyzed their active atoms. The investigation can serve as a theoretical guide to study the synthesis and activity of the title compounds. 展开更多
关键词 schiff base crystal structure quantum chemical calculation
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Synthesis, Crystal Structure and Photoluminescence of a 2D Two-fold Interpenetrating Cd(II) Coordination Polymer Based on a Flexible Reduced Schiff Base Ligand 被引量:2
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作者 应少明 陈峰 +1 位作者 黄晓辉 谢金宇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第2期193-198,共6页
By the reaction of cadmium chloride with a reduced Schiff base ligand (H2L= N-(4- carboxybenzyl)-glycine), a novel Cd(Ⅱ) compound [Cd(HL)2]·4H2O (1) has been obtained. Single-crystal X-ray diffraction ... By the reaction of cadmium chloride with a reduced Schiff base ligand (H2L= N-(4- carboxybenzyl)-glycine), a novel Cd(Ⅱ) compound [Cd(HL)2]·4H2O (1) has been obtained. Single-crystal X-ray diffraction analysis reveals that it crystallizes in orthorhombic, space group Pbcn with a = 13.9788(8), b = 24.4204(14), c = 13.9580(8) A, V= 4764.8(5) A^3, Z = 8, Mr = 600.84, Dc = 1.675 g/cm^3,/z = 0.983 mm^-1, F(000) = 2448, S = 1.084, R = 0.0806 and wR = 0.1705 (I〉 2a(1)). It displays a 2D two-fold interpenetrating structure. The Cd(Ⅱ) ions are six-coordinated. The cross-linkage of Cd(Ⅱ) ions by the bridge of HL anions results in a [Cd(HL)2] layer. Every two [Cd(HL)2]n layers are penetrated with each other, resulting in a two-fold interpenetrating double-layer structure by π-π stacking interactions and hydrogen bonds. Such double-layers are further linked by hydrogen bonds into a supramolecular structure. Photoluminescent investigation shows that compound 1 displays strong emission in the purple region. 展开更多
关键词 reduced Schiff base crystal structure PHOTOLUMINESCENT
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Optimal design and effectiveness evaluation for inerter-based devices on mitigating seismic responses of base isolated structures 被引量:3
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作者 Li Yafeng Li Shouying Chen Zhengqing 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第4期1021-1032,共12页
The optimal design and effectiveness of three control systems,tuned viscous mass damper(TVMD),tuned inerter damper(TID)and tuned mass damper(TMD),on mitigating the seismic responses of base isolated structures,were sy... The optimal design and effectiveness of three control systems,tuned viscous mass damper(TVMD),tuned inerter damper(TID)and tuned mass damper(TMD),on mitigating the seismic responses of base isolated structures,were systematically studied.First,the seismic responses of the base isolated structure with each control system under white noise excitation were obtained.Then,the structural parameter optimizations of the TVMD,TID and TMD were conducted by using three different objectives.The results show that the three control systems were all effective in minimizing the root mean square value of seismic responses,including the base shear of the BIS,the absolute acceleration of structural SDOF,and the relative displacement between the base isolation floor and the foundation.Finally,considering the superstructure as a structural MDOF,a series of time history analyses were performed to investigate the effectiveness and activation sensitivity of the three control systems under far field and near fault seismic excitations.The results show that the effectiveness of TID and TMD with optimized parameters on mitigating the seismic responses of base isolated structures increased as the mass ratio increases,and the effectiveness of TID was always better than TMD with the same mass ratio.The TVMD with a lower mass ratio was more efficient in reducing the seismic response than the TID and TMD.Furthermore,the TVMD,when compared with TMD and TID,had better activation sensitivity and a smaller stroke. 展开更多
关键词 base isolated structure inerter optimal design seismic response vibration control
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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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Characterization of the sequence spectrum of DNA based on the appearance frequency of the nucleotide sequences of the genome——A new method for analysis of genome structure 被引量:3
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作者 Masatoshi Nakahara Masaharu Takeda 《Journal of Biomedical Science and Engineering》 2010年第4期340-350,共11页
The nucleotide (base) sequence of the genome might reflect biological information beyond the coding sequences. The appearance frequencies of successive base sequences (key sequences) were calculated for entire genomes... The nucleotide (base) sequence of the genome might reflect biological information beyond the coding sequences. The appearance frequencies of successive base sequences (key sequences) were calculated for entire genomes. Based on the appearance frequency of the key sequences of the genome, any DNA sequences on the genome could be expressed as a sequence spectrum with the adjoining base sequences, which could be used to study the corresponding biological phenomena. In this paper, we used 64 successive three- base sequences (triplets) as the key sequences, and determined and compared the spectra of specific genes to the chromosome, or specific genes to tRNA genes in Saccharomyces cerevisiae, Schizosaccharomyces pombe and Escherichia coli. Based on these analyses, a gene and its corresponding position on the chromosome showed highly similar spectra with the same fold enlargement (approximately 400-fold) in the S. cerevisiae, S. pombe and E. coli genomes. In addition, the homologous structure of genes that encode proteins was also observed with appropriate tRNA gene(s) in the genome. This analytical method might faithfully reflect the encoded biological information, that is, the conservation of the base sequences was to make sense the conservation of the translated amino acids sequence in the coding region, and might be universally applicable to other genomes, even those that consisted of multiple chromosomes. 展开更多
关键词 APPEARANCE FREQUENCY of TRIPLET in GENOME base SEQUENCE SELF-SIMILARITY Analytical Method of GENOME structure
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Subtle skills: Using objective structured clinical examinations to assess gastroenterology fellow performance in system based practice milestones 被引量:1
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作者 Marianna Papademetriou Gabriel Perrault +4 位作者 Max Pitman Colleen Gillespie Sondra Zabar Elizabeth Weinshel Renee Williams 《World Journal of Gastroenterology》 SCIE CAS 2020年第11期1221-1230,共10页
BACKGROUND System based practice(SBP) milestones require trainees to effectively navigate the larger health care system for optimal patient care. In gastroenterology training programs, the assessment of SBP is difficu... BACKGROUND System based practice(SBP) milestones require trainees to effectively navigate the larger health care system for optimal patient care. In gastroenterology training programs, the assessment of SBP is difficult due to high volume, high acuity inpatient care, as well as inconsistent direct supervision. Nevertheless,structured assessment is required for training programs. We hypothesized that objective structured clinical examination(OSCE) would be an effective tool for assessment of SBP.AIM To develop a novel method for SBP milestone assessment of gastroenterology fellows using the OSCE.METHODS For this observational study, we created 4 OSCE stations: Counseling an impaired colleague, handoff after overnight call, a feeding tube placement discussion, and giving feedback to a medical student on a progress note. Twentysix first year fellows from 7 programs participated. All fellows encountered identical case presentations. Checklists were completed by trained standardized patients who interacted with each fellow participant. A report with individual and composite scores was generated and forwarded to program directors to utilize in formative assessment. Fellows also received immediate feedback from a faculty observer and completed a post-session program evaluation survey.RESULTS Survey response rate was 100%. The average composite score across SBP milestones for all cases were 6.22(SBP1), 4.34(SBP2), 3.35(SBP3), and 6.42(SBP4)out of 9. The lowest composite score was in SBP 3, which asks fellows to advocate for cost effective care. This highest score was in patient care 2, which asks fellows to develop comprehensive management plans. Discrepancies were identified between the fellows’ perceived performance in their self-assessments and Standardized Patient checklist evaluations for each case. Eighty-seven percent of fellows agreed that OSCEs are an important component of their clinical training,and 83% stated that the cases were similar to actual clinical encounters. All participating fellows stated that the immediate feedback was "very useful." One hundred percent of the fellows stated they would incorporate OSCE learning into their clinical practice.CONCLUSION OSCEs may be used for standardized evaluation of SBP milestones. Trainees scored lower on SBP milestones than other more concrete milestones. Training programs should consider OSCEs for assessment of SBP. 展开更多
关键词 Objective structured clinical exams MEDICAL education MEDICAL error SYSTEM baseD PRACTICE MILESTONES GASTROENTEROLOGY
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Syntheses and Crystal Structures of Two VO(IV) Schiff Base Complexes with Oxyammonia Ligand 被引量:1
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作者 LILian-Zhi XUTao WANGDa-Qi NIUMei-Ju JIHai-Wei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第8期865-869,共5页
Two novel VO(IV) Schiff base complexes, VO(SALHA)2[SALHA: salicyaldehyde- oxyammonia] and VO(o-VANHA)2 [o-VANHA: o-vanillin-oxyammonia], have been synthesized with salicyaldehyde or o-vanilline, hydroxylammonium chlor... Two novel VO(IV) Schiff base complexes, VO(SALHA)2[SALHA: salicyaldehyde- oxyammonia] and VO(o-VANHA)2 [o-VANHA: o-vanillin-oxyammonia], have been synthesized with salicyaldehyde or o-vanilline, hydroxylammonium chloride and vanadyl sulfate in absolute methanol, and their crystal structures were determined by single-crystal X-ray diffraction. The vanadium(IV) centers in both complexes are five-coordinate in a distorted square pyramidal geometry. VO(SALHA)2 (C14H12N2O5V, Mr = 339.20) crystallizes in the monoclinic system, space group P21/n with a = 14.716(9), b = 7.175(5), c = 14.716(9) ? b = 113.130(7), V = 1428.8(15) 3, Z = 4, Dc = 1.577 g/cm3, l = 0.71073 ? m(MoKa) = 0.720 mm-1, F(000) = 692, the final R = 0.0466 and wR = 0.0829 for 1561 observed reflections (I > 2s(I)). VO(o-VANHA)2 (C16H16N2O7V, Mr = 399.25) is of monoclinic, space group P21/n with a = 11.386(12), b = 10.405(10), c = 14.627(15) , b = 93.654(19), V = 1729(3) 3, Z = 4, Dc = 1.533 g/cm3, l = 0.71073 , m(MoKa) = 0.615 mm-1, F(000) = 820, the final R = 0.0513 and wR = 0.1129 for 1235 observed reflections (I > 2s(I)). 展开更多
关键词 vanadium complex Schiff base crystal structure
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Synthesis and Structure of Schiff Base Complex Containing'Cu_4O'Core 被引量:1
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《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1995年第3期259-263,共5页
SynthesisandStructureofSchiffBaseComplexContaining'Cu_4O'CoreMAChang-qin ̄*,YUZheng-gang,ZHANGWen-xing,WANGXu... SynthesisandStructureofSchiffBaseComplexContaining'Cu_4O'CoreMAChang-qin ̄*,YUZheng-gang,ZHANGWen-xing,WANGXu-ningandJIANGDe-h... 展开更多
关键词 Polynuclear complex Schiff base complex Crystal structure
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Crystal Structure and Sensitive Response toward Al^3+ of the Furaldehyde Schiff Base 被引量:1
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作者 朱瑞涛 薛华 +2 位作者 郭爱玲 史清华 董金龙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第6期915-923,共9页
A furaldehyde Schiff base, 4-[(2-furanylmethylene)amino]phenol(FMAP), was synthesized and fully characterized by elemental analysis, ^1H-NMR, IR, MS, UV-Vis, fluorescence and single-crystal X-ray diffraction. It c... A furaldehyde Schiff base, 4-[(2-furanylmethylene)amino]phenol(FMAP), was synthesized and fully characterized by elemental analysis, ^1H-NMR, IR, MS, UV-Vis, fluorescence and single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group P2_1/n with a = 6.2566(6), b = 13.2273(11), c = 11.3056(9) A, β = 93.1800(10)o, V = 934.19(14) A^3, Z = 4, M_r = 187.19, D_c = 1.331 g/cm^3, λ = 0.71073 a, F(000) = 392, GOOF = 1.022, R = 0.0396 and wR = 0.0992 for 4569 observed reflections with I 〉 2σ(I). Fluorescent spectroscopic investigation revealed that the Schiff base exhibited a high selectivity and sensitivity toward Al^3+ over other common metal ions in ethanol solution, and the detection limit of Al^3+ is up to 1.2 × 10^-7 M. The mass spectra and Job's plot analysis confirm the 1:1 stoichiometry between FMAP and Al^3+. 展开更多
关键词 Schiff base FURALDEHYDE crystal structure fluorescence spectrum Al^3+
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Structured Illumination Chip Based on Integrated Optics 被引量:1
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作者 刘勇 王辰 +3 位作者 Anastasia Nemkova 胡诗铭 李智勇 俞育德 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期46-49,共4页
A compact structured illumination chip based on integrated optics is proposed and fabricated on a silicon-on- insulator platform. Based on the simulation of Caussian beam interference, we adopt a chirped diffraction g... A compact structured illumination chip based on integrated optics is proposed and fabricated on a silicon-on- insulator platform. Based on the simulation of Caussian beam interference, we adopt a chirped diffraction grating to achieve a specific interference pattern. The experimental results match well with the simulations. The portability and flexibility of the structured illumination chip can be increased greatly through horizontal encapsulation. High levels of integration, compared with the conventional structured illumination approach, make this chip very compact, with a footprint of only around 1 mm2. The chip has no optical lenses and can be easily combined with a microfluidic system. These properties would make the chip very suitable for portable 3D scanner and compact super-resolution microscopy applications. 展开更多
关键词 of for structured Illumination Chip based on Integrated Optics IS on SOI into been
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