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Discrete Element with Flexible Connector for Dynamic Analysis of 3-D Beam Structures 被引量:2
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作者 Cheng, BR Zheng, ZC Hou, ZC 《China Ocean Engineering》 SCIE EI 1997年第1期11-20,共10页
Combined multi-body dynamics with structural dynamics, a new discrete element with flexible connector, which is applicable for 3-D beam structures, is developed in this paper. Both the generalized elastic coefficient ... Combined multi-body dynamics with structural dynamics, a new discrete element with flexible connector, which is applicable for 3-D beam structures, is developed in this paper. Both the generalized elastic coefficient matrix of the flexible connector and the mass matrix of discrete element may be off-diagonal in a general case. The zero-length rigid element is introduced to simulate the node at which multiple elements are jointed together. It may also be effective when the axes of adjacent elements are not in the same line. The examples for eigenvalue calculation show that the model is successful. It can be extended to the geometric nonlinear response analysis. 展开更多
关键词 discrete element flexible connector zero-length rigid element 3-d beam structures dynamic analysis
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Research on the 3-D Seismic Structures in Qinghai-Xizang Plateau 被引量:1
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作者 Ding Zhifeng, He Zhengqin, Wu Jianping, and Sun WeiguoInstitute of Geophysics, China Seismological Bureau, Beijing 100081, China 《Earthquake Research in China》 2002年第1期27-38,共12页
Based on the recording data from the analogue and broadband digital seismic stations in and around Qinghai-Xizang (Tibet) Plateau, the three dimensional (3-D) seismic velocity structures in Qinghai-Xizang Plateau were... Based on the recording data from the analogue and broadband digital seismic stations in and around Qinghai-Xizang (Tibet) Plateau, the three dimensional (3-D) seismic velocity structures in Qinghai-Xizang Plateau were obtained by using the regional body wave tomography and surface wave tomography. The results from these two tomography methods have similar characteristics for P- and S-wave velocity structures in crust and upper mantle. They show that there are remarkable low velocity zones in the upper crust of Lhasa block in the southern Qinghai-Xizang Plateau and the lower crust and upper mantle of Qiangtang block in the northern Qinghai-Xizang Plateau. These phenomena may be related to the different steps of collision process in southern and northern Qinghai-Xizang Plateau. 展开更多
关键词 Qinghai-Xizang Plateau Seismic tomography 3-d velocity structure
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Influence of Oxygen to Argon Ratio on the Structural and Morphological Properties of Nb-Doped SrTiO<sub>3</sub>Epitaxial Films Grown by Reactive Ion Beam Sputter Deposition
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作者 Gasidit Panomsuwan Nagahiro Saito 《Crystal Structure Theory and Applications》 2013年第1期34-38,共5页
Nb-doped SrTiO3 (STNO) films were grown on (001)-oriented LaAlO3 substrates by a reactive ion beam sputter deposition at various mixing ratios (OMRs) with a substrate temperature of 800oC. The STNO films exhibited goo... Nb-doped SrTiO3 (STNO) films were grown on (001)-oriented LaAlO3 substrates by a reactive ion beam sputter deposition at various mixing ratios (OMRs) with a substrate temperature of 800oC. The STNO films exhibited good crystallinity with an epitaxial orientation as characterized by high-resolution X-ray diffraction, grazing-incidence X-ray diffraction, and in-plane pole figure analysis. A decrease of out-of-plane and in-plane lattice constants was observed with an increase of OMR. The surface morphology of the STNO films showed a very dense fine-grain structure. The root-mean-square roughness was found to be increased as the OMR increased. Moreover, the elemental compositions of the STNO films were examined by X-ray photoelectron spectroscopy. 展开更多
关键词 Nb-doped SRTIO3 Epitaxial Films Crystal structure Ion beam SPUTTER Deposition
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Imaging 3-D crustal P-wave velocity structure of western Yunnan with bulletin data 被引量:17
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作者 Jing Huang Xuejun Liu +1 位作者 Youjin Su Baoshan Wang 《Earthquake Science》 CSCD 2012年第2期151-160,共10页
Western Yunnan is a region with intensive tectonic activity and serious earthquake risk. It is of significant importance to study three dimensional crustal structure of this region to understand the tectonic setting a... Western Yunnan is a region with intensive tectonic activity and serious earthquake risk. It is of significant importance to study three dimensional crustal structure of this region to understand the tectonic setting and disaster mechanism. Densification and digitalization of seismic networks in this region provides an opportunity to study the velocity structure with bulletin data. In this study, we collect P-wave data of 10 403 regional earthquakes recorded by 79 seismic stations from January 2008 to December 2010. In addition to first arrivals data (Pg with epieentral distance less than 200 km and Pn), the Pg (or P) data with epicentral distance more than 200 km are also considered as later direct arrivals in the tomographic inversion. We also compare the quantity and the quality of the seismic data before 2010 and after 2010. The test results show that adding the follow-up Pg phase can effectively improve the inversion ability of crustal imaging, and quantity and the data quality are significantly improved since 2010. The tomographie results show that: (1) The Honghe fault zone, which is the major fault systems in this region, may cut through the entire crust, and the velocity contrasts between two sides at lower crust beneath the Honghe fault are estimated at higher than 10%, while the velocity difference below Nujiang fault zone extends only in the upper crust; (2) Most of the earthquakes in the region occurred at the interface of high-velocity media and low-velocity media, i.e., the areas with high velocity gradient, which has been validated in other areas. 展开更多
关键词 regional earthquake 3-d velocity structure later phase Yunnan region
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3-D velocity structure in the central-eastern part of Qilianshan 被引量:8
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作者 ZHANG Yuan-sheng(张元生) +7 位作者 ZHOU Min-du(周民都) RONG Dai-lu(荣代潞) ZHANG Li-guang(张立光) XU Zhong-qiu(许中秋) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第3期272-281,共10页
The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the ... The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the digital seismic network set up for a Sino-French cooperation program since 1996. The inversed velocity structure does primarily reflect some important features of the deep structure in the region and provide the scientific background for the further study of active tectonic structure and the calculation of earthquake parameters. 展开更多
关键词 central-eastern Qilianshan micro-earthquake observation 3-d velocity structure focal pa-rameters joint inversion
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A study on 3-D velocity structure of crust and upper mantle in Sichuan -Yunnan region, China 被引量:6
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作者 王椿镛 Mooney W.D +3 位作者 王溪莉 吴建平 楼海 王飞 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第1期1-17,共17页
Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-D velocity structure of crust and upper mantle in the region is deter... Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-D velocity structure of crust and upper mantle in the region is determined, incorporating with previous deep geophysical data. In the upper crust, a positive anomaly velocity zone exists in the Sichuan basin, whereas a negative anomaly velocity zone exists in the western Sichuan plateau. The boundary between the positive and negative anomaly zones is the Longmenshan fault zone. The images of lower crust and upper mantle in the Longmenshan fault, Xianshuihe fault, Honghe fault and others show the characteristic of tectonic boundary, indicating that the faults likely penetrate the Moho discontinuity. The negative velocity anomalies at the depth of 50 km in the Tengchong volcanic area and the Panxi tectonic zone appear to be associated with the temperature and composition variations in the upper mantle. The overall features of the crustal and the upper mantle structures in the SichuanYunnan region are the lower average velocity in both crust and uppermost mantle, the large crustal thickness variations, and the existence of high conductivity layer in the crust or/and upper mantle, and higher geothermal value. All these features are closely related to the collision between the India and the Asia plates. The crustal velocity in the SichuanYunnan rhombic block generally shows normal value or positive anomaly, while the negative anomaly exists in the area along the large strike-slip faults as the block boundary. It is conducive to the crustal block side-pressing out along the faults. In the major seismic zones, the seismicity is relative to the negative anomaly velocity. Most strong earthquakes occurred in the upper-mid crust with positive anomaly or normal velocity, where the negative anomaly zone generally exists below. 展开更多
关键词 regional earthquake Moho discontinuity 3-d velocity structure network method plate collision SEISMICITY
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Synthesis, Structure, and Luminescent Property of a 3-D Strontium Complex [Sr_3(pda)_2(Hpda)_2(H2O)_2]_n·2nH_2O 被引量:3
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作者 陈砚美 高倩 +4 位作者 高丹丹 王德荣 李亚红 刘玮 李武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第5期746-752,共7页
The title complex [Sr3(pda)2(Hpda)2(H2O)2]n·2nH2O(H2pda = pyridine-2,6-dicar- boxylic acid) has been prepared under solvothermal conditions. It has been characterized by X-ray single-crystal diffraction, ... The title complex [Sr3(pda)2(Hpda)2(H2O)2]n·2nH2O(H2pda = pyridine-2,6-dicar- boxylic acid) has been prepared under solvothermal conditions. It has been characterized by X-ray single-crystal diffraction, IR and elemental analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 10.3795(8), b = 9.2225(7), c = 18.5726(14) , β = 104.377(2)o, V = 1722.2(2) 3, C28H22N4O20Sr3, Mr = 997.36, Z = 2, Dc = 1.923 g/cm3, μ = 4.722 mm-1, F(000) = 984, the final R = 0.0269 and wR = 0.0538. This complex possesses a 3-D structure which is constructed from 1-D chain motifs linked by carboxylate groups. The luminescent property of the title complex has been investigated. 展开更多
关键词 strontium complex crystal structure luminescent property 3-d framework
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Synthesis,Crystal Structure and Antitumor Activity of a New 3H-Phenanthro-[2,1-d]imidazole Derivative of Dehydroabietic Acid 被引量:3
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作者 谷文 苗婷婷 +3 位作者 王石发 郝云 张康平 金晓燕 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第9期1440-1445,共6页
The title compound (CI9H24BrN302, 3) was synthesized from dehydroabietic acid and its crystal structure was determined by single-crystal X-ray diffraction. The compound is of monoclinic system, slSace group C2 with ... The title compound (CI9H24BrN302, 3) was synthesized from dehydroabietic acid and its crystal structure was determined by single-crystal X-ray diffraction. The compound is of monoclinic system, slSace group C2 with a = 24.830(5), b = 7.1410(14), c = 13.981(3) A, p = 107.68(3)°, Z = 4, V= 2361.9(8) A3, Mr = 482.42, Dc = 1.357 Mg/m3, S = 1.003,μ = 1.772 mm1, F(000) = 1008, the final R = 0.0660 and wR = 0.1402 for 2244 observed reflections (I 〉 2o(/)). The crystal structure is stabilized by four hydrogen bonds (O(W)-H(WA)...O(3), O(W)-H(WB)...O(1), N(2)-H(2A)...O(W) and N(3)-H(3A)...N(1)) formed among the title compound, the crystal water and acetone molecules. The preliminary antitumor assay showed the title compound exhibited considerable inhibitory activity against HepG2 and SMMC-7721 cell lines with the ICs0 values of 17.1 and 10.2 μM, respectively. 展开更多
关键词 dehydroabietic acid 3H-phenanthro[2 1-d]imidazole crystal structure ANTITUMOR
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Synthesis and Crystal Structure of 2-Ethoxy-3-n-butyl-benzofuro [2,3-d]pyrimidin-4(3H)-one 被引量:3
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作者 胡扬根 丁明武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期21-24,共4页
The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4(3H)-one (C16H18N2O3, Mr = 286.32) has been prepared and determined by singlecrystal X-ray diffraction. The crystal is ... The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4(3H)-one (C16H18N2O3, Mr = 286.32) has been prepared and determined by singlecrystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 13.7167(14), b = 13.113(1), c = 8.378(1) A, β = 98.992(2)^o, V = 1488.4(3) A^3, Z = 4, Dc = 1.278, F(000) = 608, μ = 0.089 mm^-1, MoKa radiation (2 = 0.71073), R = 0.0498, wR = 0.1238 for 2336 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that all ring atoms in the benzo[4, 5]furo [2,3-d] pyrimi- dinone moieties are almost coplanar. 展开更多
关键词 crystal structure benzo[4 5]furo[2 3-d]pyrimidin-4(3H)-one aza-Wittig reaction synthesis
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Earthquake relocation and 3-dimensional crustal structure of P-wave velocity in central-western China 被引量:1
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作者 YANG Zhi-xian(杨智娴) +9 位作者 YU Xiang-wei(于湘伟) ZHENG Yue-jun(郑月军) CHEN Yun-tai(陈运泰) NI Xiao-xi(倪晓晞) Winston CHAN 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第1期20-30,共11页
A simultaneous inversion of earthquake relocation and three-dimensional crustal structure of P-wave velocity in central-western China (21癗~36癗, 98癊~112癊) were performed in this paper. The crustal P-wave velocity m... A simultaneous inversion of earthquake relocation and three-dimensional crustal structure of P-wave velocity in central-western China (21癗~36癗, 98癊~112癊) were performed in this paper. The crustal P-wave velocity model and earthquake relocation for this region are obtained using Pg and Sg phase readings of 9 988 earthquakes from 1992 to 1999 recorded at 193 seismic stations within central-western China by SPHYPIT90 and SPHREL3D90 programs. A lateral inhomogeneous structure of P-wave velocity in this region was obtained. Ob-vious contrast of P-wave velocities was revealed on both sides of active fault zones. Relocated epicenters of 6 459 events show clear lineation along active faults, which indicated a close correlation between seismicity and the active faults in this region. Focal depths of 82% relocated events ranged from 0 to 20 km, which is in good agreement with that from double-difference earthquake location algorithm. 展开更多
关键词 simultaneous inversion 3-d P-wave velocity structure earthquake relocation central-western China
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Synthesis and Crystal Structure of 1-(4-Fluorophenyl)-2-hexylthiobenzo[4,5]-furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5(1H)-one 被引量:4
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作者 胡扬根 杜士明 +1 位作者 李清 丁明武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第1期75-78,共4页
The crystal structure of the title compound 1-(4-fluorophenyl) -2-hexylthio-benzo [4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5(1H) -one(C23H21FN4O2S,Mr = 436.5) has been prepared and determined by single-cr... The crystal structure of the title compound 1-(4-fluorophenyl) -2-hexylthio-benzo [4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5(1H) -one(C23H21FN4O2S,Mr = 436.5) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic,space group P21/n with a = 13.9854(3) ,b = 17.2678(4) ,c = 18.1828(5)A,β = 99.364(2) °,V = 4332.58(18) A^3,Z = 4,Dc = 1.338,F(000) =1824,μ = 0.185 mm^-1,MoKa radiation(λ = 0.71073) ,R = 0.0538 and wR = 0.1162 for 4728 observed reflections with I 〉 2σ(I) . X-ray diffraction analysis reveals the fused rings of benzo[4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a] pyrimidin-5(1H) -one system are nearly coplanar. The crystal packing is mainly stabilized by weak intermolecular C-H···O hydrogen bond and π-π interactions. 展开更多
关键词 SYNTHESIS crystal structure 1-(4-fluorophenyl)-2-hexylthio-benzo[4 5]furo[3 2-d]-1 2 4-triazolo[1 5-a]pyrimidin-5(1H)-one
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3-D seismic interpretation of stratigraphic and structural features in the Upper Jurassic to Lower Cretaceous sequence of the Gullfaks Field,Norwegian North Sea:A case study of reservoir development 被引量:3
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作者 Muhammad Usman Numair Ahmed Siddiqui +3 位作者 Eduardo Garzanti Muhammad Jamil Qazi Sohail Imran Luqman Ahmed 《Energy Geoscience》 2021年第4期287-297,共11页
The 3-D seismic dataset is a key tool to analyze and understand the mechanism of structural and stratigraphic hydrocarbon(HC)trapping in the subsurface.Conventionally used subsurface seismic characterization methods f... The 3-D seismic dataset is a key tool to analyze and understand the mechanism of structural and stratigraphic hydrocarbon(HC)trapping in the subsurface.Conventionally used subsurface seismic characterization methods for fractures are based on the theory of effective anisotropy medium.The aim of this work is to improve the structural images with dense sampling of 3-D survey to evaluate structural and stratigraphic models for reservoir development to predict reservoir quality.The present study of the Gullfaks Field,located in the Norwegian North Sea Gullfaks sector,identifies the shallowest structural elements.The steepness of westward structural dip decreases eastward during the Upper Jurassic to Lower Cretaceous deposition.Reservoir sands consist of the Middle Jurassic deltaic deposits and Lower Jurassic fluvial channel and delta plain deposits.Sediment supply steadily prevails on sea-level rise and the succession displays a regressive trend indicated by a good continuous stacking pattern.The key factor for the development of reservoirs in the Gullfaks Field is fault transmissibility with spatially distributed pressure.The majority of mapped faults with sand-to-sand contacts are non-sealing,which provide restriction for the HC flow between the fault blocks.The traps for HC accumulation occur between the post-rift and syn-rift strata,i.e.antiform set by extensional system,unconformity trap at the top of syndeposition,and structural trap due to normal faults.Overall reservoir quality in the studied area is generally excellent with average 35%porosity and permeability in the Darcy range.Our findings are useful to better understand the development of siliciclastic reservoirs in similar geological settings worldwide. 展开更多
关键词 3-d seismic model Mesozoic stratigraphic boundary structural trap Reservoir quality Gullfaks Field
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Synthesis and Crystal Structure of 2-(4’-Methylphenoxy)-5,8,9-trimethyl-3-phenyl Thieno[3′,2′:5,6]pyrido[4,3-d]pyrimidin-4-(3H)-one Hydrochloride 被引量:1
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作者 LIU Jian-Chao HE Hong-Wu DING Ming-Wu 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第5期577-581,共5页
The title compound 2-(4'-methylphenoxy)-5,8,9-trimethyl-3-phenyl thieno[3',2':5,6] pyrido[4,3-d]pyrimidin-4(3H)-one hydrochloride (C26H23Cl4N3O2S, Mr = 583.33) has been determined by single-crystal X-ray dif... The title compound 2-(4'-methylphenoxy)-5,8,9-trimethyl-3-phenyl thieno[3',2':5,6] pyrido[4,3-d]pyrimidin-4(3H)-one hydrochloride (C26H23Cl4N3O2S, Mr = 583.33) has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 14.8442( 11 ), b = 11.5131 (8), c = 17.2010(13) A, β = 113.7250(10)°, V = 2691.3(3) ,A^3, Z = 4, Dc = 1.440 g/cm^3, S = 1.094,μ = 0.547 mm^-1, F(000) = 1200, the final R = 0.0571 and wR = 0.1458. X-ray analysis reveals that the title compound combines with a molecule of dichloromethane by an intramolecular hydrogen bond. The thienopyridine ring is almost coplanar, and the dihedral angle between the thiophene plane and the pyridine plane is 0.6°. 展开更多
关键词 thieno[3 2':5 6]pyrido[4 3-d]pyrimidin-4(3H)-one triphenylphosphine IMINOPHOSPHORANE crystal structure
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Synthesis and Crystal Structure of Ethyl 3-(4-Chlorophenyl)-3,4-dihydro-6-methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate 被引量:2
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作者 胡扬根 徐靖 丁明武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第6期689-692,共4页
The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined... The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215(9), b = 8.5311(4), c = 21.6886(9) A^°, β = 91.607(1)°, V = 3814.0(3)A^°^3, Z = 8, Dc = 1.400 g/cm^3, F(000) = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit. 展开更多
关键词 crystal structure ethyl 3-(4-ehlorophenyl)-3 4-dihydro-6-methyl-4-oxo-2- (pyrrolidin-1-yl)furo[2 3-d]pyrimidine-5-earboxylate aza-Wittig reaction synthesis
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Synthesis and Crystal Structure of 2-(3,3'-Bithiophen-2,2'-yl)dibenzothiazole (BTDB) and 2-(Dithieno[2,3-b:3',2' -d]thiophen-2,5-yl)dibenzothiazole (DTTDB) 被引量:1
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作者 李春丽 杨娟娟 +1 位作者 史建武 王华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第6期877-884,共8页
The title compounds, 2-(3,3'-bithiophen-2,2'-yl)dibenzothiazole (BTDB) and 2-(dithieno[2,3-b:3',2'-d]thiophen-2,5-yl)dibenzothiazole (DTTDB), have been synthesized and characterized by FT-IR, NMR, MS, HRM... The title compounds, 2-(3,3'-bithiophen-2,2'-yl)dibenzothiazole (BTDB) and 2-(dithieno[2,3-b:3',2'-d]thiophen-2,5-yl)dibenzothiazole (DTTDB), have been synthesized and characterized by FT-IR, NMR, MS, HRMS and X-ray single-crystal diffraction. The crystal of BTDB crystallizes in triclinic, space group P1 with a = 9.2207(17), b = 10.453(2), c = 10.969(2) A, V= 981.2(3) A3 and Z = 2. Crystal data of DTTDB: orthorhombic system, space group Pbcn with a = 4.5290(8), b = 13.576(3), c = 32.033(6) A, V= 1969.6(6) A3 and Z = 4. 展开更多
关键词 synthesis crystal structure 2-(3 3'-bithiophen-2 2'-yl)dibenzothiazole 2-(dithieno [2 3-b:3 2'-d] thiophen-2 5-yl)dihenzothiazole
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EFFECT OF SUBMERGED ENTRY NOZZLE (SEN) PARAMETERS AND SHAPE ON 3-D FLUID FLOW IN MOULD FOR BEAM BLANK CONTINUOUS CASTING
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作者 Y.P.Du J.W.Yang +1 位作者 R.Shi X.C.Cui 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第5期705-712,共8页
According to turbulent theory and characteristics of beam blank continuous casting, 3-D model to represent the flow of beam blank mould is established. The predicted results indicate that the exit obliquity of up 15&#... According to turbulent theory and characteristics of beam blank continuous casting, 3-D model to represent the flow of beam blank mould is established. The predicted results indicate that the exit obliquity of up 15°(+15°) should be adopted, which will benefit the floatation of non-metallic inclusion and purification of the molten steel. When the nozzle angle is 120°, the flow pattern is reasonable. Proper nozzle depth can be 200mm. Turbulent kinetic of meniscus can be reduced by adopting the square nozzle and suitable area of side outlet when casting speed increases. The results are consistent with those of water model experiment, so the model is exact and reasonable. The model can provide important information for design of SEN and defining of immersion depth. 展开更多
关键词 SEN parameter SEN shape beam blank continuous casting 3-d flow distribution turbulent kinetic energy
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Synthesis and Crystal Structure of an Interpentateing 3-D Framework Constructed from Mixed Ligands
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作者 郭鸿旭 李西忠 +2 位作者 翁文 吴小伟 吴文炳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第6期683-688,共6页
A novel organic-inorganic hybrid compound constructed from mixed ligands, Co3(SIP)2(bipy)4(H2O)6·6.5H2O (H3SIP = 5-sulfoisophthalic acid, bipy = 4,4′-bipyridyl), has been hydrothermally synthesized and c... A novel organic-inorganic hybrid compound constructed from mixed ligands, Co3(SIP)2(bipy)4(H2O)6·6.5H2O (H3SIP = 5-sulfoisophthalic acid, bipy = 4,4′-bipyridyl), has been hydrothermally synthesized and characterized by IR, TGA and single-crystal X-ray diffraction. The crystal belongs to orthorhombic, space group P212121 with a = 11.395(2), b = 19.395(4), c = 30.675(6) A^°, Mr = 1513.05, V= 6779(2) A^°^3, Dc= 1.482 g/cm^3, F(000) = 3120, μ = 0.873 mm^-1, Z= 4, the final R = 0.0439 and wR = 0.119 for 13421 observed reflections with I〉 2σ(I). The structure of the compound presents a 3-D framework containing Co-bipy 1-D chain and 2-D bilayer motifs and carboxylate spacers, and the connection of 1-D chain and 2-D bilayer motifs by carboxylate ligand results in the final open framework with twofold interpenetration net. A probe reaction of the oxidation of benzaldehyde with H2O2 using the title compound as catalyst was carded out in a liquid-solid system, showing that the compound has high oxidative catalytic activity to the reaction. 展开更多
关键词 3-d framework co-coordlnation complex twofold interpenetration net hydrothermal synthesis crystal structure catalytic activity
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3-D seismic tomography for velocity and interface structure of the crust and upper mantle(theoreticalpart)
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作者 郑需要 张先康 《Acta Seismologica Sinica(English Edition)》 EI CSCD 1998年第5期32-40,共9页
A method of three dimensional (3-D) model parameterization is presented that makes forward and inverse problems become easy. The velocity and interface structure of crust and upper mantle are described by a set of hig... A method of three dimensional (3-D) model parameterization is presented that makes forward and inverse problems become easy. The velocity and interface structure of crust and upper mantle are described by a set of highly smoothed functions. Shooting ray tracing method is chosen to calculate the ray paths for both forward and inverse problems. The partial derivatives of traveltime with respect to parameters of the model grids are calculated analytically while rays are being traced. Because velocity and interface functions have second-order continuous partial derivatives, the geometrical shadow zones at the surface caused by scattering and focusing of ray paths can be prevented. After ray tracing, an equation consisting of matrix and vectors for inverse problem is obtained. We use singular value decomposition method with damped factor to solve the equation. A synthetic data set which consists of several in-line profiles is used to test the methods. The results show that the methods are robust. Compared with the two dimensional method, the 3-D inversion method can give the right position of interfaces and the velocity structure when the crustal model is complicated. 展开更多
关键词 model parameterization ray tracing 3-d inversion crust and upper mantle structure
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Synthesis and Crystal Structure of 7-Amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-(2-nitrophenyl)-2,4-dioxo-1H-pyrano[2,3-d]pyrimidine-6-carbonitrile DMF Solvate
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作者 梁静 张梅梅 王香善 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第3期301-305,共5页
The title compound 7-amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-(2-nitrophenyl)- 2,4- dioxo-1H-pyrano[2,3-d] pyrirnidine-6-carbonitrile DMF solvate 1 (C19H20N6O6, Mr = 428.41) was synthesized and crystallized. The cr... The title compound 7-amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-(2-nitrophenyl)- 2,4- dioxo-1H-pyrano[2,3-d] pyrirnidine-6-carbonitrile DMF solvate 1 (C19H20N6O6, Mr = 428.41) was synthesized and crystallized. The crystal belongs to the monoclinic system, space group P2 1/c with a = 11.383(2), b = 13.372(2), c = 13.673(2)A, β = 97.380(4)°, Z = 4, V = 2063.8(6)A^3, Dc = 1.379 g/cm^3,μ(MoKα) = 0.105 mm^-1, F(000) = 896, the final R = 0.0738 and wR = 0.1647 for 2964 observed reflections (I〉 2σ(I)). X-ray analysis reveals that the new pyran ring is coplanar, which is obviously different from those of other similar compounds. In addition, the unclassical hydrogen bonds of C-H…O and C-H…N are presented in the crystals except for the normal hydrogen bonds of N-H…O. 展开更多
关键词 crystal structure pyrano[2 3-d] pyrimidine synthesis
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Efficient Synthesis,Crystal Structure and Antibacterial Activity of Two Novel Thieno[2,3-d]pyrimidin-4(3H)-one Derivatives
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作者 LI Rong-Kun YANG Quan-Li +2 位作者 HUANG Nian-Yu CHEN Hong LIU Ming-Guo 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第5期673-680,共8页
Two new thieno[2,3-d]pyrimidin-4(3H)-one derivatives,C24H22 Cl N3O2S(5a) and C25H25N3O2S(5b),have been synthesized via a tandem aza-Wittig reaction.This tandem reaction has many attractive aspects such as easily... Two new thieno[2,3-d]pyrimidin-4(3H)-one derivatives,C24H22 Cl N3O2S(5a) and C25H25N3O2S(5b),have been synthesized via a tandem aza-Wittig reaction.This tandem reaction has many attractive aspects such as easily accessible and versatile starting materials,mild conditions and high yields.Both compounds have been characterized by elemental analysis,HR-MS,IR,NMR spectra and X-ray single-crystal diffraction.Compound 5a crystallizes in monoclinic,space group P21/c with a = 9.986(3),b = 14.263(4),c = 15.530(5)A,β = 93.806(5)o,V = 2207.1(11) A^3,Mr = 451.96,Z = 4,Dc = 1.360 g/cm3,F(000) = 944,μ = 0.294 mm-1,Mo Kα radiation(λ = 0.71073 A),the final R = 0.0444 and w R = 0.1219 for 3407 observed reflections with I 〉 2σ(I).Compound 5bcrystallizes in triclinic,space group P1 with a = 8.974(4),b = 10.766(5),c = 12.260(6) A,β = 93.047(7)o,V = 1122.1(9) A^3,Mr = 431.54,Z = 2,Dc = 1.277 g/cm3,F(000) = 456,μ = 0.170 mm-1,Mo Kα radiation(λ = 0.71073 A),the final R = 0.0378 and w R = 0.1072 for 3806 observed reflections with I 〉 2σ(I).The preliminary antibacterial activities of 5a and 5b were investigated.Compound 5a showed 71.3% and 79.2% in vitro inhibition against Fusarium oxysporium and Rhizoctonia solani,respectively.Compound 5b showed 75.3% in vitro inhibition against Rhizoctonia solani. 展开更多
关键词 crystal structure thieno[2 3-d]pyrimidinone aza-Wittig reaction synthesis antibacterial activity
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