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The Appreciation of “Everyday Use” from the Perspective of Post-structuralism
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作者 康宏伟 《海外英语》 2012年第2X期192-193,共2页
"Everyday Use" is well-known story written by Alice Walker, who is a very famous black female writer. This paper will focus on using the decontructionism strategy to dismantle the binary oppositions of the s... "Everyday Use" is well-known story written by Alice Walker, who is a very famous black female writer. This paper will focus on using the decontructionism strategy to dismantle the binary oppositions of the story. The binary oppositions are "Pretty VS. Ugly, Civilized VS. Unenlightened, Hang VS. Use and The Mainstream Culture VS. Non-mainstream Culture". By analyzing, the paper concludes that no culture can be defeated and each culture needs to be passed on. Different cultures should respect each other. 展开更多
关键词 EVERYDAY USE BINARY oppositions post-structuralism
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Innovative Applications of Post-Tension for Restoration and Rehabilitation of Bridges and Structures--Case Studies in India
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作者 Ramesh Kommajosyula Narapraju Venkat Ramana Rao 《Journal of Civil Engineering and Architecture》 2014年第7期869-880,共12页
This paper deals with new and innovative case studies of application of post-tensioning for restoration of structures for buildings, bridges and rock stabilization in India. In earlier situations for these types of ca... This paper deals with new and innovative case studies of application of post-tensioning for restoration of structures for buildings, bridges and rock stabilization in India. In earlier situations for these types of cases conventional method of repair and rehabilitation has been used. These innovative approaches for restoration have led to enormous saving of cost and time. The advantages of post tensioning are well known in the civil industry and are being used for the last 40 to 50 years. Post tensioning is one of the best methods to induce stresses in the concrete before application of live load and this technique can also be widely used for restoration and rehabilitation of structures. Unlike the use of post-tensioning in new structures there are no definite methods or codes for application in restoration and rehabilitation of structures. For restoration and rehabilitation of structures, PT (post tensioned) technique can be applied in combination with other techniques and materials available. Bridge lifting is a tricky and risky job especially when the superstructure is displaced appreciably by a natural calamity, etc.. Not only the present state of structure needs proper study before commencement of restoration and rehabilitation but also calls for careful execution. This paper deals with case studies of innovative applications of post tensioning in restoration and rehabilitation of structures and restoration of bridge structure in Andaman & Nicobar Island, India affected by Sumatra quake. 展开更多
关键词 RESTORATION REHABILITATION structures external post tensioning rock stabilization.
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Barrellite and Pillarrite: A Description and a Mode of Formation of a Novel Post-Sedimentary Twin Structures from As-Subbiyah, North of Kuwait Bay, Kuwait
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作者 Ali T. Al-Mishwat 《International Journal of Geosciences》 2021年第7期625-634,共10页
I report on the occurrence of a pair of novel and related post-sedimentary structures that form in the Neogene cross</span><span style="font-family:Verdana;">-</span><span style="fo... I report on the occurrence of a pair of novel and related post-sedimentary structures that form in the Neogene cross</span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">bedded red sandstones in the As-Subbiyah area, north of Kuwait Bay, Kuwait. I named them barrellite and pillarrite. Barrellite forms as vertical tubes of concentric sheaths of siltstone with partially hollow interior or intervening homogeneous and structure-less sandstone. It stands as barrels above the background sandstone. Pillarrite forms as discrete, vertical and solitary spines of homogeneous sandstone and siltstone, or inside barrellite masses from which successive siltstone sheaths were stripped. The structures range in diameter from one-centimeter poke marks to one-meter-wide barrels and hunks, and their vertical length exceeds two meters. Barrellite, pillarrite and their complex intergrowths develop near thin quartz veins and chaotic zones, and form with them complex geometrical relationships. The dual structures are genetically related and fall within the general class of tubular structures in sedimentary rocks. I consider them as a special type of sand injectites.</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">The mode of formation of these structures is enigmatic. They develop in a geological setting that displays evidence of a widespread and vigorous oil field brine. I suggest a tentative scenario for their </span><span style="font-family:Verdana;">formation, involving flushing of the brine through hydraulic fracturing of the sedimentary succession above the Ebharah Oil Field reservoir in the As-Subbiyah area. The brine plucks mineral and rock fragments and mixes</span><span style="font-family:Verdana;"> with them along its paths, producing a heterogeneous slurry. Ultimately, the slurry solidifies as barrellite and pillarrite, chaotic zones and quartz veins. The vertical nature of the structures, circular and internal concentric arrangements, as well as the homogenous lithology inside their masses mimic characteristics of flow and deposits in vertical and horizontal pipelines. 展开更多
关键词 Barrellite Pillarrite As-Subbiyah KUWAIT post-Sedimentary Twin structure
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Analysis of nonlinear stability and post-buckling for Euler-type beam-column structure
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作者 朱媛媛 胡育佳 程昌钧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第6期719-728,共10页
Based on the assumption of finite deformation, the Hamilton variational principle is extended to a nonlinear elastic Euler-type beam-column structure located on a nonlinear elastic foundation. The corresponding three-... Based on the assumption of finite deformation, the Hamilton variational principle is extended to a nonlinear elastic Euler-type beam-column structure located on a nonlinear elastic foundation. The corresponding three-dimensional (3D) mathematical model for analyzing the nonlinear mechanical behaviors of structures is established, in which the effects of the rotation inertia and the nonlinearity of material and geometry are considered. As an application, the nonlinear stability and the post-buckling for a linear elastic beam with the equal cross-section located on an elastic foundation are analyzed. One end of the beam is fully fixed, and the other end is partially fixed and subjected to an axial force. A new numerical technique is proposed to calculate the trivial solution, bifurcation points, and bifurcation solutions by the shooting method and the Newton- Raphson iterative method. The first and second bifurcation points and the corresponding bifurcation solutions are calculated successfully. The effects of the foundation resistances and the inertia moments on the bifurcation points are considered. 展开更多
关键词 beam-column structure Hamilton variational principle nonlinear stability shooting method Newton-Raphson iterative method post-BUCKLING
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Prediction of Protein OmpH in Structure of C47-8 Pasteurella multocida
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作者 繁萍 张瑞强 +3 位作者 张卫 丰琳琅 陈忍霞 赵静 《Agricultural Science & Technology》 CAS 2012年第6期1186-1189,1206,共5页
[Objective] This study aimed to predict the structure of protein OmpH from Pasteurella multocida C47-8 (PmC47-8) strain of yak. [Method] Online BLAST, signal peptide prediction, secondary structure prediction and pr... [Objective] This study aimed to predict the structure of protein OmpH from Pasteurella multocida C47-8 (PmC47-8) strain of yak. [Method] Online BLAST, signal peptide prediction, secondary structure prediction and protein characteristics of sequencing result of gene OmpH from PmC47-8 strain were analyzed. [Result] The similarities of gene OmpH from PmC47-8 with the published 81 OmpH genes were between 84% and 99%; a signal peptide was found with the cleavage sites between 20 and 21 in the polypeptide; secondary structure prediction showed that folding structure accounted for 49.8% and loop structure for 50.2%; it predicted that there were 7 O-glycosylation sites in OmpH protein with the amino acid residual sites of 2, 45, 48, 330, 716, 721, 723, respectively, and 2 N-glycosylation sites with the amino acid residual sites of 15 and 35. [Conclusion] This study lays the foundation for the study on the immunity of OmpH gene from yak. 展开更多
关键词 PmC47-8 strain OmpH protein structure PREDICTION
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Crashworthiness design and experimental validation of a novel collision post structure for subway cab cars 被引量:3
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作者 XING Jie XU Ping +3 位作者 ZHAO Hui YAO Shu-guang WANG Qian-xuan LI Ben-huai 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第9期2763-2775,共13页
This paper proposes a novel collision post structure designed to improve the crashworthiness of subway cab cars.The structure provides two innovative features:1)a simpler connection between the post and the car roof,w... This paper proposes a novel collision post structure designed to improve the crashworthiness of subway cab cars.The structure provides two innovative features:1)a simpler connection between the post and the car roof,which gives a more reasonable load transfer path to reduce the stress concentration at the joint;and 2)a stiffness induction design that provides an ideal deformation model to protect the safe space of the cab cars.The novel collision post structure was evaluated with finite element analysis,and a prototype cab car was mechanically tested.The results demonstrate that the deformation response was stable and agreed well with the expected ideal mode.The maximum load was 874.17 kN and the responses remained well above the elastic design load of 334 kN as required by the design specification.In addition,there was no significant tearing failure during the whole test process.Therefore,the novel collision post structure proposed has met the requirements specified in new standard to improve the crashworthiness of subway cab cars.Finally,the energy absorption efficiency and light weight design highlights were also summarized and discussed. 展开更多
关键词 collision post structure subway cab cars CRASHWORTHINESS quasi-static test
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Periodic oscillation and fine structure of wedge-induced oblique detonation waves 被引量:11
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作者 Ming-Yue Gui Bao-Chun Fan Gang Dong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第6期922-928,共7页
An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection model.The fifth-order WENO scheme is adopted to captur... An oblique detonation wave for a Mach 7 inlet flow over a long enough wedge of 30 turning angle is simulated numerically using Euler equation and one-step rection model.The fifth-order WENO scheme is adopted to capture the shock wave.The numerical results show that with the compression of the wedge wall the detonation wave front structure is divided into three sections:the ZND model-like strcuture,single-sided triple point structure and dual-headed triple point strucuture.The first structure is the smooth straight,and the second has the characteristic of the triple points propagating dowanstream only with the same velocity,while the dual-headed triple point structure is very complicated.The detonation waves facing upstream and downstream propagate with different velocities,in which the periodic collisions of the triple points cause the oscillation of the detonation wave front.This oscillation process has temporal and spatial periodicity.In addition,the triple point trace are recorded to obtain different cell structures in three sections. 展开更多
关键词 Oblique detonation wave Wedge - Periodic oscillation Fine structure
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Finite element analysis on nut post structure of Three Gorges Project ship lift 被引量:2
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作者 石端伟 蔡栋材 吴志纯 《Journal of Central South University》 SCIE EI CAS 2009年第4期614-620,共7页
A nonlinear finite element model of the nut post reinforced concrete (RC) structure of the safety mechanism in the Three Gorges Project (TGP) ship lift was built by ANSYS software. Some irregular structures such a... A nonlinear finite element model of the nut post reinforced concrete (RC) structure of the safety mechanism in the Three Gorges Project (TGP) ship lift was built by ANSYS software. Some irregular structures such as the nut post and the rotary rod were divided by curved surface into a series of regular parts, and the structures were all meshed to hexahedron. Constraint equations were defined between two interfaces with different element sizes and mesh patterns. PRETS179 elements were used to simulate the preload in the tendons and the pre-stressed screws, and the loss of prestressing force was calculated. Five extreme load cases were analyzed. The stress of each part in the structure was obtained. The results indicate that the maximum compressive stress of concrete C35 is 24.13 MPa, so the concrete may be partially crushed; the maximum tensile stress of the grouting motar is 6.73 MPa, so the grouting motar may partially fracture; the maximum yon Mises stress of the rotary rod is 648.70 MPa, therefore the rotary rod may partially yield. 展开更多
关键词 ship lift safety mechanism nut post reinforced concrete structure finite element analysis
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Continental- Margin Structure of Northeast China and Its Adjacent Areas 被引量:11
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作者 Tang Kedong, Shenyang Institute of Geology and Mineral Resources, Shenyang,Liaoning ProvinceWang Ying,Bureau of Geology and Mineral Resources of Heilongjiang Province,Harbin, HeilingjiangHe Guoqi and Shao Ji’an Peking U niversity, Beijing Liu Xinzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1995年第3期241-258,共18页
The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to... The continental margin of Northeast China and its adjacent areas is composed of two tectonic belts. The inner belt is a collage made up of fragments resulting from breakup of an old land with the north part related to the evolution of the Palaeo-Asian Ocean and the south part to the evolution of the Palaeo - Pacific Ocean. The outer belt is a Mesozoic terrane, which is a melange made up of fragments of the Late Palaeozoic to Early Mesozoic oceanic crust and the Late M esozoic trench accumulations.There existed another ocean-the Palaeo - Pacific Ocean during the period from the closing of the Palaeo-Asian Ocean to the opening of the modern Pacific Ocean or from the Devonian to Jurassic, and the ocean-floor spreading of the Palaeo - Pacific Ocean led to the formation of the above-mentioned tectonic belts. The development of the strike-slip fault system after the Late Jurassic and the formation of an epicontinental volcano -plutonic rock belt in the Late Cretaceous to Early Tertiary are attributed to the interaction between the modern Pacific plate and the Eurasian plate. 展开更多
关键词 continental-margin structure Bohai Sea block Mesozoic terrane non- subducted ocean crust Palaeo - Pacific Ocean
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Synthesis and Structure of 2-Isobutyl-6-(2',4'-dichlorophenyl)imidazo[2,1-b]-1,3,4-thiadiazole 被引量:7
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作者 LIMing WENLi-Rong +2 位作者 FUWei-Jun HUFang-Zhong YANGHua-Zheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第1期11-14,共4页
The crystal structure of the title compound, 2-isobutyl-6-(2?4?dichlorophenyl)- imidazo[2,1-b]-1,3,4-thiadiazole (C14H13Cl2N3S, Mr = 326.23), has been synthesized by the treatment of 2-amino-5-isobutyl-1,3,4-thiadiazo... The crystal structure of the title compound, 2-isobutyl-6-(2?4?dichlorophenyl)- imidazo[2,1-b]-1,3,4-thiadiazole (C14H13Cl2N3S, Mr = 326.23), has been synthesized by the treatment of 2-amino-5-isobutyl-1,3,4-thiadiazole with a-chloroaceto-2,4-dichlorophenone and determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a = 12.483(7), b = 8.420(4), c = 14.998(8) ? b = 105.770(10)? V = 1517.0(14) 3, Z = 4, Dc = 1.428 g/cm3, S = 0.902, m(MoKa) = 0.558 mm-1, F (000) = 672, R = 0.0579 and wR = 0.1186. The X-ray analytic results showed that all ring atoms in the imidazothiadiazole moiety are almost coplanar. The dihedral angel between the phenyl group and hetero-cycle is 16.8(0.2)? 展开更多
关键词 crystal structure imidazo[2 1-b]-1 3 4-thiadiazole SYNTHESIS
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Symplectic analysis for elastic wave propagation in two-dimensional cellular structures 被引量:5
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作者 Xiu-Hui Hou Zi-Chen Deng +1 位作者 Jia-Xi Zhou Tie-Quan Liu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第5期711-720,共10页
On the basis of the finite element analysis, the elastic wave propagation in cellular structures is investigated using the symplectic algorithm. The variation principle is first applied to obtain the dual variables an... On the basis of the finite element analysis, the elastic wave propagation in cellular structures is investigated using the symplectic algorithm. The variation principle is first applied to obtain the dual variables and the wave propagation problem is then transformed into two-dimensional (2D) symplectic eigenvalue problems, where the extended Wittrick-Williams algorithm is used to ensure that no phase propagation eigenvalues are missed during computation. Three typical cellular structures, square, triangle and hexagon, are introduced to illustrate the unique feature of the symplectic algorithm in higher-frequency calculation, which is due to the conserved properties of the structure-preserving symplectic algorithm. On the basis of the dispersion relations and phase constant surface analysis, the band structure is shown to be insensitive to the material type at lower frequencies, however, much more related at higher frequencies. This paper also demonstrates how the boundary conditions adopted in the finite element modeling process and the structures' configurations affect the band structures. The hexagonal cells are demonstrated to be more efficient for sound insulation at higher frequencies, while the triangular cells are preferred at lower frequencies. No complete band gaps are observed for the square cells with fixed-end boundary conditions. The analysis of phase constant surfaces guides the design of 2D cellular structures where waves at certain frequencies do not propagate in specified directions. The findings from the present study will provide invaluable guidelines for the future application of cellular structures in sound insulation. 展开更多
关键词 Cellular structures Symplectic analysis Dispersion relation - Phase constant surface Sound insulation
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Synthesis, Crystal Structure, Fluorescent Property and DFT Calculations of a New Zn(Ⅱ) Complex Based on 3-(2-Pyridyl)-5-(4-pyridyl)-1H-1,2,4-triazole 被引量:7
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作者 靳晓东 李冰 +2 位作者 高慧 张霞 刘万毅 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第7期1129-1136,共8页
A new coordination compound Zn(2,4'-bpt)2(H2O)(1) based on the versatile ligand 2,4'-Hbpt(2,4?-Hbpt = 3-(2-pyridyl)-5-(4-pyridyl)-1H-1,2,4-triazole) was prepared by hydrothermal reactions. The structure... A new coordination compound Zn(2,4'-bpt)2(H2O)(1) based on the versatile ligand 2,4'-Hbpt(2,4?-Hbpt = 3-(2-pyridyl)-5-(4-pyridyl)-1H-1,2,4-triazole) was prepared by hydrothermal reactions. The structure of complex 1 has been characterized by X-ray single-crystal diffraction, elemental analysis, X-ray powder diffraction, IR spectrum analysis and thermogravimetric analysis. Single-crystal X-ray diffraction analysis indicates that the complex belongs to monoclinic system, space group C2/c with a = 23.877(3), b = 0.7483(9), c = 1.2492(2) A, b = 92.681(2)°, V = 2230.6(4) A^3, Z = 4, Dc = 1.572 g/cm^3, m = 1.143 mm^-1, Mr = 527.85 and F(000) = 1080. The final R = 0.0581 and wR = 0.0898 with I 〉 2s(I). 1 is a 0D motif which is connected by hydrogen bonds to form a corrugated 1D pattern. In addition, 1 shows strong photoluminescent emissions in the solid state at room temperature which can be used as potential optical materials. Theoretical calculations based on density functional theory(DFT) were employed in order to explicate the stability and chemical reactivity of 2,4'-Hbpt with different conformations. The results indicated that conformation I is more stable and prior to coordination in the reactions. 展开更多
关键词 3-(2-pyridyl)-5-(4-pyridyl)-1H-1 2 4-triazole conformation crystal structure fluorescence theoretical analysis
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Internal structures and high-velocity frictional properties of Longmenshan fault zone at Shenxigou activated during the 2008 Wenchuan earthquake 被引量:3
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作者 Yu Wang Shengli Ma +7 位作者 Toshihiko Shimamoto Lu Yao Jianye Chen Xiaosong Yang Honglin He Jiaxiang Dang Linfeng Hou Tetsuhiro Togo 《Earthquake Science》 2014年第5期499-528,共30页
This paper reports internal structures of a wide fault zone at Shenxigou,Dujiangyan,Sichuan province,China,and high-velocity frictional properties of the fault gouge collected near the coseismic slip zone during the 2... This paper reports internal structures of a wide fault zone at Shenxigou,Dujiangyan,Sichuan province,China,and high-velocity frictional properties of the fault gouge collected near the coseismic slip zone during the 2008 Wenchuan earthquake.Vertical offset and horizontal displacement at the trench site were 2.8 m(NW side up)and 4.8 m(right-lateral),respectively.The fault zone formed in Triassic sandstone,siltstone,and shale about 500 m away from the Yingxiu-Beichuan fault,a major fault in the Longmenshan fault system.A trench survey across the coseismic fault,and observations of outcrops and drill cores down to a depth of 57 m revealed that the fault zone consists of fault gouge and fault breccia of about0.5 and 250-300 m in widths,respectively,and that the fault strikes N62°E and dips 68° to NW.Quaternary conglomerates were recovered beneath the fault in the drilling,so that the fault moved at least 55 m along the coseismic slip zone,experiencing about 18 events of similar sizes.The fault core is composed of grayish gouge(GG) and blackish gouge(BG) with very complex slip-zone structures.BG contains low-crystalline graphite of about 30 %.High-velocity friction experiments were conducted at normal stresses of 0.6-2.1 MPa and slip rates of 0.1-2.1 m/s.Both GG and BG exhibit dramatic slip weakening at constant high slip rates that can be described as an exponential decay from peak friction coefficient lpto steadystate friction coefficient lssover a slip-weakening distance Dc.Deformation of GG and BG is characterized by overlapped slip-zone structures and development of sharp slickenside surfaces,respectively.Comparison of our data with those reported for other outcrops indicates that the high-velocity frictional properties of the Longmenshan fault zones are quite uniform and the high-velocity weakening must have promoted dynamic rupture propagation during the Wenchuan earthquake. 展开更多
关键词 Wenchuan earthquake - Longmenshan faultsystem - Shenxigou fault zone Fault zone structures High-velocity friction
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Synthesis, Crystal Structure and DNA-Binding Property of a Mn(Ⅱ) Complex Based on 5-(Tri-fluoromethyl)pyridine-2-carboxylic Acid 被引量:4
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作者 WANG Jia-Kai LI Bing +2 位作者 WU Huan-Ping TIAN Xiao-Yan MA Xiao-Xia 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第8期1349-1355,共7页
A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic ... A new complex Mn(Htpc)2(H2O)2(1, Htpc = 5-(trifluoromethyl)pyridine-2-carboxylic acid) has been synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction. 1 belongs to triclinic system, space group P■ with a = 5.0885(10), b = 6.5574(13), c = 14.016(3) ?, β = 90.67(3)o, V = 436.34(17) ?3, Z = 1, Dc = 1.793 g·cm-3, μ = 0.855 mm-1, Mr = 471.18, F(000) = 235, the final R = 0.0454 and wR = 0.1134 for 1998 observed reflections with I > 2σ(I). The Mn(Ⅱ) ion is coordinated by two N and two O atoms from two Htpc as well as two O atoms from two coordinated water molecules, forming a 0D motif with distorted octahedral coordinate geometry. The adjacent 0D units are linked into 1D chains through hydrogen bond O(1W)–H(1 WB)···O(2), and via the O(1 W)–H(1 WA)···O(1) hydrogen bond the neighboring 1D chains are connected into a 2D supramolecular layer. Moreover, the interactions between the ligand and its complex with CT-DNA were studied by EtBr fluorescence probe, which suggested that these compounds bind to CT-DNA through an intercalation mode. The binding constants were 0.41 and 0.64 for Htpc and complex 1, respectively. It indicates that the interaction between complex 1 and CT-DNA is stronger than Htpc. 展开更多
关键词 5-(trifluoromethyl)pyridine-2-carboxylic acid crystal structure DNA fluorescence SPECTRA
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Structural, mechanical, and electronic properties of 25 kinds of Ⅲ–Ⅴbinary monolayers: A computational study with first-principles calculation 被引量:2
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作者 Xue-Fei Liu Zi-Jiang Luo +5 位作者 Xun Zhou Jie-Min Wei Yi Wang Xiang Guo Bing Lv Zhao Ding 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第8期258-269,共12页
Using first-principle calculations, we investigate the mechanical, structural, and electronic properties and formation energy of 25 kinds of Ⅲ–V binary monolayers in detail. A relative radius of the binary compound ... Using first-principle calculations, we investigate the mechanical, structural, and electronic properties and formation energy of 25 kinds of Ⅲ–V binary monolayers in detail. A relative radius of the binary compound according to the atomic number in the periodic table is defined, and based on the definition, the 25 kinds of Ⅲ–V binary compounds are exactly located at a symmetric position in a symmetric matrix. The mechanical properties and band gaps are found to be very dependent on relative radius, while the effective mass of holes and electrons are found to be less dependent. A linear function between Young’s modulus and formation energy is fitted with a linear relation in this paper. The change regularity of physical properties of B–V(V = P, As, Sb, Bi) and Ⅲ–N(Ⅲ = Al, Ga, In, Tl) are found to be very different from those of other Ⅲ–V binary compounds. 展开更多
关键词 DENSITY FUNCTIONAL theory -Ⅴbinary monolayers BAND structure MECHANICAL properties
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Syntheses, Crystal Structures and DNA-binding Properties of Zn(Ⅱ), Ni(Ⅱ) and Co(Ⅱ) Compounds Containing Thiazole Derivatives 被引量:3
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作者 齐爽 李雨涵 +4 位作者 杨宇 贺玉婷 蔡健 林世威 岳淑美 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第12期1945-1959,1845,共16页
Zn(Ⅱ), Ni(Ⅱ) and Co(Ⅱ) compounds(1~3) based on 2-(2-pyridyl)benzothiazole(bpt) and terephthalic acid(PTA) were synthesized. The crystal structures of [Zn(bpt)(PTA)2](1), [Ni(bpt)(PTA)2](2), and [Co(bpt)(PTA)2](3) ... Zn(Ⅱ), Ni(Ⅱ) and Co(Ⅱ) compounds(1~3) based on 2-(2-pyridyl)benzothiazole(bpt) and terephthalic acid(PTA) were synthesized. The crystal structures of [Zn(bpt)(PTA)2](1), [Ni(bpt)(PTA)2](2), and [Co(bpt)(PTA)2](3) have been determined by single-crystal X-ray diffraction analysis, which shows that all the three complexes belong to monoclinic system with space group P21/c. Time-dependent density functional theory(TD-DFT) calculation is performed on a reference structure of compound 3. The excited electrons mainly localized at the π* of ligand 2-(2-pyridyl)benzothiazole, which will be convenient for them to bind with the DNA reacting sites. Fluorescence spectroscopy, ultraviolet(UV) spectroscopy and viscosity were used to characterize the interaction of the compounds with Calf thymus DNA(CT-DNA). The results indicate that compounds 1~3 bind to CT-DNA and have a strong interaction with DNA. The compounds can probably bind to CT-DNA via a non-intercalative mode as concluded by studying the viscosity of a DNA solution in the presence of the compounds. This combination can effectively break DNA, which speculates that these three compounds may interact with the cancer cell DNA in this binding mode, thereby damaging the cancer cells. 展开更多
关键词 calf thymus DNA 2-(2-pyridyl)benzothiazole single-crystal structures spectroscopy
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Synthesis, Crystal Structure and Antitumor Activity of (E)-4-tert-Butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine 被引量:5
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作者 胡艾希 覃智 +1 位作者 叶姣 夏曙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第11期1680-1683,共4页
The title compound (E)-4-tert-butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-thiazol-2-amine with 2,4-dichlorobe... The title compound (E)-4-tert-butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-thiazol-2-amine with 2,4-dichlorobenzaldehyde, and its crystal structure was determined by singlecrystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 7.9748(4), b = 10.1803(5), c = 11.4603(6), α = 102.882(1), β = 100.253(1), γ = 104.457(1)°, V = 850.95(7)3, Z = 2, F(000) = 392, C16H15Cl2N5S, Mr = 380.29, Dc = 1.484 g/cm3, S = 1.095, μ = 0.512 mm-1, the final R = 0.0301 and wR = 0.0965 for 3334 observed reflections (I 〉 2σ(I)). The preliminary antitumor activity shows that for the title compound the IC50 of Hela is 0.175 μmol/mL and that of Bel7402 is 0.156 μmol/mL. 展开更多
关键词 (E)-4-tert-butyl-N-(2 4-dichorobenzylidene)-5-(1 2 4-triazl-1-yl)-thiazol-2-amine crystal structure synthesis antitumor activity
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Crystal Structure and Luminescence of a New Zn(Ⅱ) Complex [Zn(L)(IPP)(H_2O)]·2H_2O Based on Nicotinate Derivative and 1,10-Phenanthroline Derivative 被引量:2
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作者 WANG Xiu-Yan LIU Rui +3 位作者 LI Fang-Yuan MENG Xiang-Yue SUN Qing-Hong ZHAO Zhong-Yu 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第6期960-964,共5页
A new Zn(II) complex, [Zn(L)(IPP)(H2O)]'2H2O(1, H2L = 3-carboxy-l-car- boxymethyl-2-oxidopyridinium and IPP = 2-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)phenol), was synthesized under hydrothermal condi... A new Zn(II) complex, [Zn(L)(IPP)(H2O)]'2H2O(1, H2L = 3-carboxy-l-car- boxymethyl-2-oxidopyridinium and IPP = 2-(1H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)phenol), was synthesized under hydrothermal conditions and its structure was determined by single-crystal X-ray diffraction. It crystallizes in triclinic, space group Pi with a = 8.5023(17), b = 9.945(2), c = 15.573(3) A, a = 95.87(3), β = 102.56(3), y = 100.73(3)°, V= 1248.7(4) A3, Z= 2, C27H22N5O9Zn, Mr= 625.87, Dc = 1.665 g/cm^3, F(000) = 642, μ(MoKa) = 1.053 mm^-1, R = 0.0474 and wR = 0.1352. In 1, one L2-, one 1PP and one water molecule coordinate to the same Zn(II) atom to give a discrete complex with two lattice water molecules. Adjacent [Zn(L)(IPP)(H20)].2H20 molecules interact through π-π stacking between two IPP ligands to form a supramolecular chain. The N-H…O and O-H…N hydrogen bonds further stabilize the supramolecular chain structure of 1. The solid state luminescent property of 1 was also studied. 展开更多
关键词 crystal structure hydrogen bonds π-π stackings luminescent property
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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 and Crystal Structure of a New Copper(II) Complex with 4-Cyanobenzoic Acid 被引量:6
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作者 LI Yan WU A-Qing +3 位作者 ZHENG Fa-Kun GUO Guo-Cong LU Can-Zhong HUANG Jin-Shun 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第11期1281-1285,共5页
A new Cu(Ⅱ) complex [Cu(4-cba)(1,10-phen)(H2O)2](NO3) (4-Hcba = 4-cyanobenzoic acid) has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characteriz... A new Cu(Ⅱ) complex [Cu(4-cba)(1,10-phen)(H2O)2](NO3) (4-Hcba = 4-cyanobenzoic acid) has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100 ℃ and structurally characterized by single-crystal X-ray diffraction. Crystallographic data: C20H16CuN4O7, Mr= 487.91, triclinic, space group PI, a = 7.8420(2), b = 9.1070(2), c = 15.1140(6) A, a = 76.889(9), β = 81.332(11), γ = 74.844( 11)°, V = 1009.89(5) A^3, Z = 2, Dc = 1.605 g/cm^3, F(000) = 498, μ = 1.134 mm^-1, the final R = 0.0379 and wR = 0.0865 for 2977 observed reflections with 1 〉 2σ(Ⅰ). The Cu(Ⅱ) atom is coordinated by two terminal water molecules, one chelating 1,10-phen molecule and one monodentate 4-cba ligand to form a slightly distorted square pyramid. The title complex molecules are connected through hydrogen bonds and π-π stacking interactions to generate a 2D layered network. The thermogravimetric analysis of the title complex has also been discussed. 展开更多
关键词 copper(Ⅱ) complex 4-cyanobenzoic acid crystal structure hydrogen bonds π-π stacking
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