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Synthesis and Crystal Structure of (2S,5S)-1-Aza-2- (2-pyridyl)-3-oxa-4,4-diphenylbicyclo [3.3.0] Octane
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作者 LU Jun JI Shun-Jun +3 位作者 QIAN Rong JIANG Zhao-Qin ZHANG Yong LANG Jian-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第6期527-530,共4页
The title compound (C23H22N2O) 3 has been synthesized by the reaction of (S)- (-)-1,1-diphenyl-2-pyrrolidinemethanol 1 with 2-pyridinecarboxaldehyde 2 in refluxing benzene catalyzed by TsOH, and its structure was dete... The title compound (C23H22N2O) 3 has been synthesized by the reaction of (S)- (-)-1,1-diphenyl-2-pyrrolidinemethanol 1 with 2-pyridinecarboxaldehyde 2 in refluxing benzene catalyzed by TsOH, and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to orthorhombic, space group P212121 with a = 8.4747(8), b = 10.8829(10), c = 19.777(2) , Mr = 342.43, V =1824.0(3) 3, Dc = 1.247 g/cm3, Z = 4, m = 0.077 mm-1 and F(000) = 728. The structure was solved by direct methods and refined by full-matrix least-squares techniques to the final R = 0.0497 and wR = 0.0927. 展开更多
关键词 sYNTHEsIs crystal structure (2s 5s)-1-aza-2-(2-pyridyl)-3-oxa-4 4- diphenylbicyclo [3.3.0] octane
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Synthesis and Crystal Structure of N-[(2S)-4-bromo-2-(L-menthyloxy)-5-oxo-2,5-dihydro-3-furyl]-L-leucine
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作者 宋秀美 王宁 +1 位作者 汪朝阳 冯宗财 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第12期1719-1724,共6页
Starting from(5S)-(L-menthyloxy)-3,4-dibromo-5H-furan-2-one and L-leucine,the title compound N-[(2S)-4-bromo-2-(L-menthyloxy)-5-oxo-2,5-dihydro-3-furyl]-L-leucine 5(C20H32BrNO5,Mr = 446.37) was obtained in o... Starting from(5S)-(L-menthyloxy)-3,4-dibromo-5H-furan-2-one and L-leucine,the title compound N-[(2S)-4-bromo-2-(L-menthyloxy)-5-oxo-2,5-dihydro-3-furyl]-L-leucine 5(C20H32BrNO5,Mr = 446.37) was obtained in one-pot process via the tandem Michael addition-elimination reaction in the presence of potassium hydroxide.The chemical structure and absolute configuration of the title compound were confirmed via rotation,UV-Vis,FT-IR,1H NMR,13C NMR,MS and elemental analysis,especially by the X-ray single-crystal diffraction.The crystal crystallizes in an orthorhombic system,space group P212121 with a = 12.5249(16),b = 19.005(3),c = 19.719(3) ,V = 4693.7(10) 3,Z = 8,Dc = 1.263 g/m3,μ = 1.778 mm-1,F(000) = 1872,the final R = 0.0617 and wR = 0.1576 for 3967 observed reflections(I 2σ(I)).X-ray analysis reveals that the title compound has two independent molecules in the asymmetric part of the unit cell with the two five-membered furanones being almost planar.The essential part of the electron delocalization is concentrated in the N(1),C(3),C(1),C(37) and O(7) region and N(2),C(28),C(27),C(30) and O(4) region in the other molecule respectively,but does not take place at the expense of delocalization within the ester function. 展开更多
关键词 (5s-(L-menthyloxy)-3 4-dibromo-5H-furan-2-one L-LEUCINE tandem Michael addition-elimination reaction one-pot process crystal structure
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Synthesis and Crystal Structure of S,S'-Bis(8-quinolyl)-1,8-dithiaoctane
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作者 陈春龙 苏成勇 +4 位作者 蔡跃鹏 刘俊 周忠远 陈新滋 康北笙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第1期21-24,共4页
The title compound S,S?bis(8-quinolyl)-1,8-dithiaoctane crystallizes in the monoclinic system, space group P21/n with a = 7.537(1), b = 20.434(3), c = 13.857(2) , = 97.102(3)? V = 2117.8(5) 3, Dc = 1.269 g/cm3, Z = ... The title compound S,S?bis(8-quinolyl)-1,8-dithiaoctane crystallizes in the monoclinic system, space group P21/n with a = 7.537(1), b = 20.434(3), c = 13.857(2) , = 97.102(3)? V = 2117.8(5) 3, Dc = 1.269 g/cm3, Z = 4, C24H24N2S2, Mr = 404.57, (MoK? = 0.263 mm-1 and F(000) = 856, and its structure was refined to R = 0.0417 and wR = 0.1077 for 2814 observed reflections (I > 2(I)). The compound crystallizes in conformations A and B with equal occupation ratio. A acts as both a donor and acceptor in the CH… interactions, but B only acts as a donor. Edge-to-face CH…?interactions between AA along the a axis and BABA along the c axis result in an infinite layered-structure in the ac plane. 展开更多
关键词 s s-bis(8-quinolyl)-1 8-dithiaoctane intermolecular C-H…π interaction crystal structure
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Crystal Structure of Phenol,2-[4(S)-4-Dihydro-4-benzyl-2-ozazolinyl]
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作者 罗梅 周仕明 +3 位作者 张家海 庞文民 尹浩 胡克良 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第6期947-949,共3页
The compound phenol,2-[4(S)-4,5-dihydro-4-phenyl-2-ozazolinyl(1,C15H13NO2) was synthesized with a simple,one step method free of water and air.It was obtained in a moderate yield from the reaction of 2-hydroxybenz... The compound phenol,2-[4(S)-4,5-dihydro-4-phenyl-2-ozazolinyl(1,C15H13NO2) was synthesized with a simple,one step method free of water and air.It was obtained in a moderate yield from the reaction of 2-hydroxybenzonitrile with optically active amino alcohol in chloroben-zene under dry,anaerobic conditions.It belongs to the orthorhombic system,space group P212121 with a = 5.786(5),b = 10.730(5),c = 19.722(5),C15H13NO2,Mr = 239.26,V = 1224.4(12)3,Z = 4 and Dc = 1.298 mg/m3.The final R = 0.0324 for 1627 observed reflections with Ⅰ 〉 2σ(Ⅰ) and Rw = 0.0826 for all data.The structure of compound 1 was determined by X-ray diffraction,NMR and HRMS. 展开更多
关键词 OXAZOLINE PHENOL 2-[4(s-4 5-dihydro-4-phenyl-2-ozazolinyl (C15H13NO2) crystal structure
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Synthesis and Crystal Structure of (1S)-1,1'-Bis{[N-ethyl-N-(1-methylethyl)-amino]-carbonyl}-2-(hydroxydiphenylmethyl)-ferrocene
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作者 YUAN Hao ZHOU Zhi-Ming XU Bao-Cai 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第7期827-830,共4页
The title complex,(1S)-1,1'-bis{[N-ethyl-N-(1-methylethyl)-amino]carbonyl}-2-(hydroxyldiphenylmethyl)-ferrocene([Fe(C_(24)H_(22)NO_(2))(C_(11)H_(16)NO)]_(2)·H_(2)O,Mr=1207.13),was synthesized via(-)-Sparteine... The title complex,(1S)-1,1'-bis{[N-ethyl-N-(1-methylethyl)-amino]carbonyl}-2-(hydroxyldiphenylmethyl)-ferrocene([Fe(C_(24)H_(22)NO_(2))(C_(11)H_(16)NO)]_(2)·H_(2)O,Mr=1207.13),was synthesized via(-)-Sparteine-mediated enantioselective directed ortho-lithiation of 1,1‘-bis{[N-ethyl-N-(1-methylethyl)-amino]carbonyl}-2-(hydroxydiphenylmethyl)-ferrocene.The structure of the rifle compound was determined by X-ray single-crystal diffraction.The crystal belongs to the orthorhombic system,space group P2_(1)2_(1)2_(1),with a=10.266(2),b=17.676(4),c=34.097(7)A,V=6187(2)A3,Z=4,C_(70)H_(86)Fe_(2)N_(4)O_(7),Dc=1.296 g/cm^(3),μ=0.527 mm^(-1),T=113(2)K,F(000)=2568,the final R=0.0469 and wR=0.0984 for 13940 observed reflections with I〉2σ(I).The neighboring ferrocene derivatives are joined into dimers via O-H…O=C intermolecular hydrogen bonding by a water molecule.Besides,the dimers form neat rows along the a axis. 展开更多
关键词 (1s)-1 1'-bis{[N-ethyl-N-(1-methylethyl)-amino]carbonyl}.2-(hydroxydiphenylmethyl)-ferrocene enantioselective synthesis crystal structure
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Synthesis, Characterization and Crystal Structure of (+)-N-[(3S)-3-(4- fluorophenyl)heptanoyl]bornane-10,2-sultam
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作者 韩勰 汪淼 +2 位作者 李菲 徐媛原 曹秀芳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第9期1247-1250,共4页
The chiral molecule (+)-N-[(3S)-3-(4-fluorophenyl)heptanoyl]bornane-10,2-sultam (C23H32FNO3S, Mr = 421.56), a fluorine-containing derivative of camphorsultam, was conveniently obtained and crystallized in the... The chiral molecule (+)-N-[(3S)-3-(4-fluorophenyl)heptanoyl]bornane-10,2-sultam (C23H32FNO3S, Mr = 421.56), a fluorine-containing derivative of camphorsultam, was conveniently obtained and crystallized in the orthorhombic space group P212121 with a = 7.9044(11), b = 11.6680(16), c = 24.899(3) , V = 2296.4(5) 3, Z = 4, Dc = 1.219 Mg/m3, λ = 0.71073 , μ(MoKα) = 0.172 mm-1 and F(000) = 904. X-ray diffraction analysis reveals that the six-membered ring of sultam shows a boat conformation (Fig. 1). The planes constructed by ((C6), (C7), (C8), (C9)) and ((C4), (C5), (C6), (C9)) form a dihedral angle of 70.3(3)°. The plane of (C1)-(C2)-(C3) forms dihedral angles to the aforementioned planes of 85.9(4) and 89.5(4)°, respectively. The molecules are linked via C-H···O/F interactions. 展开更多
关键词 (+)-N- [(3s-3-(4-fluorophenyl)heptanoyl] bornane-10 2-sultam synthesis crystal structure
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Synthesis and Crystal Structure of N-[(3aR,4R,4aR,5aS,6S,6aS)-1,3-Dioxooctahydro-4,6-ethenocyclopropa[f]isoindol-2(1H)-yl]-3-(trifluoromethyl)phenylmethanimine
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作者 周辛波 谢云德 +2 位作者 钟武 王建柏 李松 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第8期1231-1235,共5页
The crystal structure of the title compound(C19H15F3N2O2,Mr = 360.33) was determined by single-crystal X-ray diffraction.The crystal belongs to triclinic,space group P1,with a = 6.5604(7),b = 13.9614(16),c = 18.... The crystal structure of the title compound(C19H15F3N2O2,Mr = 360.33) was determined by single-crystal X-ray diffraction.The crystal belongs to triclinic,space group P1,with a = 6.5604(7),b = 13.9614(16),c = 18.1790(18) ,α = 102.749(7),β = 97.542(6),γ = 94.355(4)°,V = 1600.5(3) 3,Z = 4,Dc = 1.495 g/cm3,λ(MoKα) = 0.71070,F(000) = 744,μ(MoKα) = 0.122 mm-1,R = 0.0434 and wR = 0.1051.A total of 7590 unique reflections were collected,of which 5429 with |F|2 ≥ 2σ|F|2 were observed.The two cyclohexene rings in the molecule adopt boat-boat conformations with the deviations of ring atoms C(9) and C10 from the C(5)/C(6)/C(7)/C(8) plane(Ⅰ) by 1.1204(0.0023) and 1.1132(0.0023) ,respectively,whereas from the C(2)/C(3)/C(5)/C(8) plane(Ⅱ) by 1.1627(0.0022) and 1.1818(0.0021) ,respectively.In the cyclopropane and lactam rings,atoms C(11) and N(1) point towards the double bond of C(9)-C(10) and the dihedral angle between the ring plane(Ⅲ) containing C(1),C(2),C(3) and C(4) and plane(IV) consisting of C(6),C(7) and C(11) is 55.76(0.07)°.The dihedral angles between planes Ⅳ and Ⅰ and Ⅱ and Ⅲare 63.58(0.07)° and 58.10(0.06)°,respectively.The dihedral angle between the benzene ring C(13)~ C(18) and plane Ⅳ is 42.41(0.06)°. 展开更多
关键词 N-[(3aR 4R 4aR 5as 6s 6as-1 3-dioxooctahydro-4 6-ethenocyclopropa[f]isoin-dol-2(1H)-yl]-3-(trifluoromethyl)phenylmethanimine crystal structure synthesis
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Synthesis and X-ray Crystal Structure of a Methylene-bridged Glycoluril Dimer
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作者 佘能芳 吴彦东 +1 位作者 孙静静 吴安心 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第1期47-50,共4页
The synthesis and X-ray crystal structure of a methylene-bridged glycoluril dimer 2 was reported.The methylene-bridged glycoluril dimer 2(C38H36Br4N8O12,Mr=1116.35) crystallizes in space group P1 with a=10.5802(6)... The synthesis and X-ray crystal structure of a methylene-bridged glycoluril dimer 2 was reported.The methylene-bridged glycoluril dimer 2(C38H36Br4N8O12,Mr=1116.35) crystallizes in space group P1 with a=10.5802(6),b=16.8469(9),c=24.7673(14) ,α=98.00,β=96.263(1),γ=101.606(1)o,V=4239.3(4)3,Z=4,Dc=1.749 g/cm3,μ=3.869 mm-1 and F(000)=2224.It crystallizes in an S-shaped conformation that displays two ethoxycarbonyl groups on each face of the molecule. 展开更多
关键词 methylene-bridged glycoluril dimer X-ray crystal structure s-shape
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Quantum Chemical Study of Geometric Structures and Properties for Ag_nH_2S(n = 1~10) Clusters
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作者 温俊青 徐卫锋 +2 位作者 刘柯阳 陈国祥 文振翼 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第10期1487-1495,共9页
The stable structures and stabilities of AgnH2S(n = 1-10) clusters have been calculated using the B3P86-DFT method. The results predicate that the stable geometries of AgnH2 S clusters can be got by directly adding ... The stable structures and stabilities of AgnH2S(n = 1-10) clusters have been calculated using the B3P86-DFT method. The results predicate that the stable geometries of AgnH2 S clusters can be got by directly adding the H2 S molecule on different sites of Agn clusters. Agn clusters would like to bond with sulfur atom and the H2 S molecules are partial to adsorb at the top site in the clusters. After adsorption, the structures of Agn clusters and H2 S molecule keep the original structures except Ag9. The binding energy of AgnH2 S is distinctly larger than that of pure Agn clusters. The second difference in energy and the HOMO and LUMO gaps of Agn and AgnH2 S exhibit an obvious odd-even oscillation, which demonstrate that the stabilities of even-numbered silver clusters are relatively more stable than the neighboring odd-numbered silver clusters. Mulliken population analysis shows that charges always transfer from the H2 S molecule to Agn clusters in all clusters. 展开更多
关键词 density functional theory AgnH2s(n = 1-10) clusters structures sTABILITIEs
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Synthesis,Characterization and Structure of Chiral Amino Acids and Their Corresponding Amino Alcohols with Camphoric Backbone
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作者 QIAN Hui-Fen HUANG Wei +1 位作者 LI Hui-Hui YAO Cheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第10期1243-1249,共7页
Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-(+)-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among t... Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-(+)-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among them, one intermediate (1S,3R)-3-amino-2,2,3- trimethyl cyclopentane-1-carboxylic acid hydrochloride 3 was structurally elucidated by X-ray diffraction techniques. Versatile intermolecular hydrogen bonding interactions observed in its packing structure result in a two-dimensional framework. 展开更多
关键词 chiral amino acids and amino alcohols (1s 3R)-3-amino-2 2 3-trimethyl-cyclopentane-1-carboxylic acid hydrochloride hydrogen-bonding interactions crystal structures
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青藏高原东南缘兰坪-思茅盆地反S型构造属性的古地磁约束 被引量:7
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作者 徐颖超 仝亚博 +1 位作者 王恒 杨振宇 《地质论评》 CAS CSCD 北大核心 2017年第3期549-567,共19页
兰坪—思茅(盆地)内部发育的一系列褶皱和逆冲断层组成了显著的弧形构造,其中部呈现反S形构造形态。该地区地壳构造变形方式及其演化过程与青藏高原东南缘地壳物质新生代侧向挤出逃逸密切相关,对其开展地壳构造变形方式的定量分析,具有... 兰坪—思茅(盆地)内部发育的一系列褶皱和逆冲断层组成了显著的弧形构造,其中部呈现反S形构造形态。该地区地壳构造变形方式及其演化过程与青藏高原东南缘地壳物质新生代侧向挤出逃逸密切相关,对其开展地壳构造变形方式的定量分析,具有重要的意义。本文通过兰坪—思茅盆地中部反S形构造区域四条白垩纪红层剖面的岩石磁学和古地磁学研究,获得南涧牛街地区早白垩世LN-a和LN-b剖面的特征剩磁方向分别为D_s=244.7°,I_s=-47.3°,Ks=31.6,α_(95)=16.6°(K_1j^1),和D_s=245.4°,I_s=-46.4°,K_s=52.2,α_(95)=9.4°(K_1n^2),两剖面在99%置信度下通过了Mc Fadden(1990)褶皱检验;小湾镇地区早白垩世NX-a和NX-b剖面(两套地层分属轴向不同的两褶皱)特征剩磁方向分别为D_s=244.9°,I_s=-40.2°,K_s=1067.5,α_(95)=2.3°(K_1j^1)和D_s=182.6°,I_s=-42.1°,K_s=335.2,α_(95)=3.7°(K_1j^2)。结合前人在兰坪—思茅地体中部获得的可靠古地磁数据及青藏高原东南缘区域新生代断裂活动演化过程的分析,指出兰坪—思茅盆地中部弧形反S形构造的形成和演化,以及兰坪—思茅盆地构造区内部差异性旋转变形作用主要受控于新生代时期青藏高原东南缘地壳块体侧向旋转挤出过程中的相互挤压作用和临沧花岗岩基对兰坪—思茅地体侧向顺时针旋转挤出运动的阻挡等一系列构造因素。 展开更多
关键词 白垩纪 古地磁 兰坪-思茅盆地 s形构造成因 旋转变形
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湖南通道地区金矿床成矿流体特征及成矿物质来源:来自流体包裹体、H-O-S同位素的证据 被引量:4
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作者 谢玉华 高华 +10 位作者 张哲 杨亮 柯新星 刘晓敏 罗建镖 刘琦 许坤林 刘继顺 王智琳 孔华 刘飚 《黄金科学技术》 CSCD 2021年第1期74-89,共16页
通道地区金矿床位于雪峰弧形金锑矿带西南段,主要包括茶溪、金坑和黄垢3个中小型金矿床,矿脉发育在前寒武系浅变质地层中,受断裂控制明显,矿石类型为石英脉型与蚀变岩型。通过野外地质调查、显微鉴定、流体包裹体测试及H、O、S同位素分... 通道地区金矿床位于雪峰弧形金锑矿带西南段,主要包括茶溪、金坑和黄垢3个中小型金矿床,矿脉发育在前寒武系浅变质地层中,受断裂控制明显,矿石类型为石英脉型与蚀变岩型。通过野外地质调查、显微鉴定、流体包裹体测试及H、O、S同位素分析,对成矿流体特征与成矿物质来源进行约束。分析结果表明:成矿过程主要划分为2个阶段,一是石英+黄铁矿+毒砂+绢云母+金阶段;二是石英+绢云母+少量金阶段;其中茶溪矿区第一阶段石英包裹体均一温度为155~297℃,峰值为210~220℃,盐度[w(NaCl)]为4.9%~11.7%,第二阶段石英包裹体均一温度为135~233℃,峰值为160~170℃,盐度为3.3%~9.7%;金坑矿区第一阶段石英包裹体均一温度为202~261℃,峰值为210~220℃,盐度为5.6%~10.1%,第二阶段石英包裹体均一温度为134~203℃,峰值为150~160℃,盐度为3.8%~8.8%;黄垢矿区第一阶段石英包裹体均一温度为176~319℃,峰值为220~240℃,盐度为5.1%~11.7%;3个矿床中成矿流体的H-O同位素组成具有相似的变化趋势,第一阶段δ^(18)O_(fluid)变化较小,分布在+4.95‰~+6.95‰之间,第二阶段δ^(18)O_(fluid)分布在+1.08‰~+1.38‰之间,而δD值变化较大,分布在-83‰~-33‰之间,因此第一阶段成矿流体为中温中低盐度的流体,来源以变质流体为主,可能有岩浆热液的叠加,第二阶段成矿流体为低温低盐度的流体,指示有大气水的混入。另外,黄垢矿区黄铁矿中的δ^(34)S值分布范围较广,为-15.79‰~+3.88‰;金坑矿区硫化物δ^(34)S值较为集中,为-5.02‰~+0.74‰。结合区域地层中S同位素组成与黄铁矿电子探针分析,认为载金硫化物硫源(δ^(34)S值接近零值)主要为深部岩浆,而不含金或含微量金的硫化物(δ^(34)S值为负值)来源于围岩地层。 展开更多
关键词 雪峰弧形构造带 金矿床 石英流体包裹体 H-O-s同位素 流体特征 通道地区 湖南省
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基于断距-层厚特征统计的反倾边坡S型破坏演化数值模拟 被引量:11
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作者 马昊 黄达 石林 《工程地质学报》 CSCD 北大核心 2020年第6期1160-1171,共12页
三峡库区巫峡龚家坊至独龙一带存在大量反倾不稳定边坡,多具有薄厚互层和软硬相间的岩体结构,边坡高度普遍在500 m以上。现场调查表明独龙7#边坡(D7)具有明显的“S”型柔性变形现象。为探明反倾边坡“S”型变形破坏机制,以独龙段反倾边... 三峡库区巫峡龚家坊至独龙一带存在大量反倾不稳定边坡,多具有薄厚互层和软硬相间的岩体结构,边坡高度普遍在500 m以上。现场调查表明独龙7#边坡(D7)具有明显的“S”型柔性变形现象。为探明反倾边坡“S”型变形破坏机制,以独龙段反倾边坡为依托,从边坡的岩体结构调查、破坏模式概化、监测资料分析、变形破坏模拟等角度对软硬互层反倾高边坡的破坏机制进行研究。通过现场调查与无人机倾斜摄影,建立了边坡的三维模型,进而提取航拍数据,获得了岩层厚度、断距等的统计规律;基于断距-层厚统计规律,通过离散元软件UDEC对库水软化作用下D7边坡“S”型变形机理进行了模拟分析。研究表明:(1)独龙段边坡普遍具有陡倾内逆向层状结构,发育3组结构面,岩体被切割成块;(2)根据软岩占比,可将独龙段边坡分为2类:A类边坡软岩层占约20%,断距/层厚值分布于0.7~2.8区间,并集中于1.2~1.8;B类边坡软岩层占比约10%,断距/层厚值分布于0.5~3.3区间,并集中于0.6~1.5;A类边坡岩体长细比更大;(3)长期监测表明,边坡在库水位低值时位移量大,D7边坡位移持续增大,潜在整体失稳;(4)离散元模拟表明,边坡破裂面自坡脚延伸,中部硬岩区起到支撑并抑制上部变形的作用,边坡硬岩区与软岩区的差异变形以及变形体不同部位惯性的差异是导致岩层“S”型变形的主因,最终分别过“S”形岩层两个反弯点形成两条剪切带,形成自下而上的柔性弯曲-滑移型破坏。(5)断距-层厚比(S/T)可影响边坡破坏模式,比值越大,反折变形区与坡脚垮塌区越小,当S/T≥2时,S型变形不再发育。 展开更多
关键词 无人机倾斜摄影 结构面统计 反倾边坡 弯曲倾倒 s型破坏
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A search for evidence of small-scale inhomogeneities in dense cores from line profile analysis
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作者 Lev Pirogov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第8期97-102,共6页
In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming... In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming cores S140 and S199 were carried out. The data were processed by the Fourier filtering method. Line temperature fluctuations that exceed the noise level were detected. Assuming the cores consist of a large number of randomly moving small thermal fragments, the total number of frag- ments is - 4 × 106 for the region with linear size - 0.1 pc in S140 and - 106 for the region with linear size - 0.3 pc in S 199. Physical parameters of fragments in S 140 were obtained from detailed modeling of the HCN emission in the framework of the clumpy cloud model. 展开更多
关键词 LINEs profiles - molecular data - methods data analysis - IsM clouds - IsM molecules - IsM structure - IsM individual objects s 140)
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某S形人行景观桥的方案优化与深化设计
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作者 施政 《城市道桥与防洪》 2024年第2期86-91,I0012,共7页
对某S形人行景观桥进行方案优化与深化设计的过程,包括主梁结构体系、菱形斜交网架、桥墩造型三个方面的优化。此三者都是基于三维参数化设计。设计的最终目标,是在尽量还原方案造型的基础上,使得景观桥梁的主梁、网架、桥墩各部分比例... 对某S形人行景观桥进行方案优化与深化设计的过程,包括主梁结构体系、菱形斜交网架、桥墩造型三个方面的优化。此三者都是基于三维参数化设计。设计的最终目标,是在尽量还原方案造型的基础上,使得景观桥梁的主梁、网架、桥墩各部分比例和谐,达到形态与受力的统一。 展开更多
关键词 人行桥 钢结构 斜交网格 参数化设计 s形景观桥
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“S”型覆岩空间结构煤柱导致冲击失稳的力学机制探讨 被引量:16
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作者 史红 王存文 +1 位作者 孔令海 成云海 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2012年第A02期3508-3513,共6页
进入深部开采后,决定矿山压力显现程度的运动岩层在厚度和层面方向上已经超出传统的平面模型范围,所形成的覆岩空间结构的运动影响着采动应力场的分布,煤柱及其周围由于采动引起的应力重分布和应力集中是诱发煤柱冲击失稳的应力条件和... 进入深部开采后,决定矿山压力显现程度的运动岩层在厚度和层面方向上已经超出传统的平面模型范围,所形成的覆岩空间结构的运动影响着采动应力场的分布,煤柱及其周围由于采动引起的应力重分布和应力集中是诱发煤柱冲击失稳的应力条件和根本原因。因此,通过分析覆岩空间结构的运动规律及其采动应力场分布,并以此探讨作用在残留煤柱的力源,是研究煤柱诱发冲击失稳机制的理论基础。以华丰煤矿六层煤残留煤柱为研究对象,通过研究四层煤开采形成的"S"型覆岩空间结构岩层运动特点和六层煤上覆岩层运动规律,分析作用在煤柱上的复合应力,探讨煤柱力源,通过应力计算和微地震监测分析煤柱及其周围的应力场的分布规律,研究煤柱导致动力失稳的应力条件和机制,研究结果表明,四层煤和六层煤开采形成的高应力是煤柱诱发动力失稳的应力条件,而煤柱及其周围形成的高应力差是动力失稳的根本诱因;基于煤柱应力分析,探讨高应力区煤柱卸压解危的措施。 展开更多
关键词 采矿工程 s”型覆岩空间结构 煤柱 冲击地压 微地震监测 力学机制
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旋转喷射泵S形叶片复合叶轮的设计 被引量:6
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作者 李德忠 杨军虎 陈长青 《石油机械》 北大核心 2005年第10期16-19,1-2,共4页
在介绍旋转喷射泵的工作原理及特点后,重点论述了旋转喷射泵的设计理论,讨论了S形叶片复合叶轮结构参数的计算方法和取值范围。结合设计实例,给出1个S形叶片二级复合叶轮的设计结构参数,加工出复合叶轮并组装成旋转喷射泵进行试验,拟和... 在介绍旋转喷射泵的工作原理及特点后,重点论述了旋转喷射泵的设计理论,讨论了S形叶片复合叶轮结构参数的计算方法和取值范围。结合设计实例,给出1个S形叶片二级复合叶轮的设计结构参数,加工出复合叶轮并组装成旋转喷射泵进行试验,拟和出泵试验性能曲线。与后弯式叶片复合叶轮泵性能曲线相比,这种泵扬程和流量均有所增加,泵性能达到了设计指标和要求。 展开更多
关键词 旋转喷射泵 工作原理 结构特点 结构参数 复合叶轮 石油机械
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S形铺管托管架的结构刚度研究 被引量:4
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作者 谢鹏 岳前进 赵岩 《石油机械》 北大核心 2014年第1期62-65,共4页
随着海底管道铺设逐步走向深海,托管架长度和管道质量也随之增加,导致托管架相对刚度变小,在管道压力的作用下,托管架发生整体变形甚至破坏。鉴于此,基于Abaqus软件,建立"海洋石油201"托管架的精细有限元模型,计算了不同铺管... 随着海底管道铺设逐步走向深海,托管架长度和管道质量也随之增加,导致托管架相对刚度变小,在管道压力的作用下,托管架发生整体变形甚至破坏。鉴于此,基于Abaqus软件,建立"海洋石油201"托管架的精细有限元模型,计算了不同铺管工况下托管架的整体结构刚度,探讨了A型支架吊点位置对托管架刚度的影响,并建立了可考虑托管架整体结构刚度的Orcaflex模型。研究结果表明,深水铺管时,托管架承受管道载荷和重力的综合作用而发生变形,其中第1节变形最小,后2节变形较大;改变A型支架吊点位置可调整托管架的整体结构刚度。 展开更多
关键词 s形铺管 托管架 结构刚度 吊点位置 末端挠度 有限元分析
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S型叶片周围复杂流态的研究 被引量:1
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作者 康灿 杨敏官 +1 位作者 刘栋 王群 《中国农村水利水电》 北大核心 2007年第4期63-65,共3页
在水洞实验台上进行了S型叶片绕流的实验观察与实验数据采集。对不同攻角、不同雷诺数下的S叶片周围流态进行了分析,借助于气泡的形态变化对流态进行了深入探讨。实验中发现:随着攻角的增大,S叶片尾部射流逐渐加强,同时S型叶片正面流态... 在水洞实验台上进行了S型叶片绕流的实验观察与实验数据采集。对不同攻角、不同雷诺数下的S叶片周围流态进行了分析,借助于气泡的形态变化对流态进行了深入探讨。实验中发现:随着攻角的增大,S叶片尾部射流逐渐加强,同时S型叶片正面流态随攻角的增大逐渐失稳;S叶片尾部存在着复杂的加速流、射流与尾涡结构之间的相互作用,随雷诺数增大,这种相互作用变得愈加强烈;可以预测S型叶片易发生空化的区域在前缘处,空化的形式为局部空化。研究结果为新型叶片设计提供了依据,并为使用S型叶片的转轮的流体动力学性能预测提供了参考。 展开更多
关键词 s型叶片 水洞实验 高速摄影 流动结构
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大陆边缘反S状造山带三维模式兼论青藏高原结构与隆升 被引量:5
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作者 李东旭 《地质力学学报》 CSCD 2007年第1期31-41,共11页
文中根据北美大陆西南边缘造山带的构造地貌及新构造运动特征,建立了反S状大陆边缘造山带的三维构造力学模式,指出阿拉斯加地区为弧形右旋剪切隆升造山带;科迪勒拉造山带为直线右旋走滑造山带;马德雷山以南,延至加勒比海为一左旋沉降‘... 文中根据北美大陆西南边缘造山带的构造地貌及新构造运动特征,建立了反S状大陆边缘造山带的三维构造力学模式,指出阿拉斯加地区为弧形右旋剪切隆升造山带;科迪勒拉造山带为直线右旋走滑造山带;马德雷山以南,延至加勒比海为一左旋沉降‘旋扭沟-弧-盆系统’。以此模式检验欧亚大陆南缘造山带,确定从阿尔卑斯经扎格罗斯、喜马拉雅至印度尼西亚蜿蜒曲折的山链是由四个反S状造山带连锁而成,导致它们的分解为四个构造体系的原因,与南半球冈瓦纳大陆裂解有关。依据上述的区域构造规律,作者认为青藏高原内部结构的原型为旋扭沟-弧-盆系统,属帕米尔—喀喇昆仑—喜马拉雅反S状造山带尾弧的组成部分。后经印度板块俯冲、青藏—三江—印度尼西亚反S状造山带头部弧右旋隆升两组动力系统叠加结果。 展开更多
关键词 s状旋扭造山带 旋扭沟--盆系统 青藏高原结构与隆升 大陆边缘造山带
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