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三维网状结构聚金属氧酸盐K_4SiW_(12)O_(40)·16H_2O的合成及其X射线晶体结构分析 被引量:2
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作者 党东宾 柏艳 王敬平 《化学研究》 CAS 2003年第1期4-7,共4页
以钨酸钠(Na2WO4·2H2O),硅酸钠(Na2SiO3·9H2O)和氯化钾(KCl)为原料在水溶液中反应制得了标题化合物,单晶X射线结构分析表明,属单斜晶系,空间群Cc,晶胞参数a=2.0180(4),b=2.0178(4),c=1.2498(3)nm,β=90.08(3)°,V=5.0892(... 以钨酸钠(Na2WO4·2H2O),硅酸钠(Na2SiO3·9H2O)和氯化钾(KCl)为原料在水溶液中反应制得了标题化合物,单晶X射线结构分析表明,属单斜晶系,空间群Cc,晶胞参数a=2.0180(4),b=2.0178(4),c=1.2498(3)nm,β=90.08(3)°,V=5.0892(18)nm3,Z=4,Dc=4.290g/cm3.对5850个独立的衍射点[I>2σ(I)]进行全矩阵最小二乘法修正后,可靠性因子R1=0.0598. 展开更多
关键词 三维网状结构 聚金属氧酸盐 K4SIW12040.16H20 合成 x射线晶体结构分析 杂多化合物 杂多酸 KEGGIN结构
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一种新的环状膦酸酐的合成与X射线晶体结构
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作者 安德烈 张英俊 彭志鸿 《化学学报》 SCIE CAS CSCD 北大核心 2004年第12期1166-1170,MJ05,共6页
2 ,4 二叔丁基 6 甲氧基苯膦二硫化物 [MoxP(S) 2 ,1]与H2 O/吡啶封管反应分别以 3 0 %和 2 2 %的收率得到一种新的环状膦酸酐的异构体 2a和 2b .通过3 1PNMR对反应过程的追踪探讨了 2的形成机制 .X射线晶体结构解析表明异构体 2b分子... 2 ,4 二叔丁基 6 甲氧基苯膦二硫化物 [MoxP(S) 2 ,1]与H2 O/吡啶封管反应分别以 3 0 %和 2 2 %的收率得到一种新的环状膦酸酐的异构体 2a和 2b .通过3 1PNMR对反应过程的追踪探讨了 2的形成机制 .X射线晶体结构解析表明异构体 2b分子中有一个不规则的含磷六元杂环 .环内最大键角为 12 7.7° ,最小键角为 97.9° .六元杂环中 ,除CC具有双键性质外 ,其余的CP ,CO和PO键均具有典型的单键特征 .两个环外PS双键处于含磷杂环的同一侧 ,表明 2b分子是一个cis结构 .该晶体属单斜晶系 ,C2 /c空间群 ,a =2 .0 486( 3 )nm ,b =2 .2 3 66( 4 )nm ,c =1.63 3 4( 3 )nm ,β =112 .98( 1)° ,Z =8,V =6.890 ( 1)nm3 ,Dc=1.2 61g·cm-3 ,F( 0 0 0 ) =2 80 0 .0 0 ,μ(MoKα) =3 .40cm-1.最终偏差因子R =0 .0 63 ,Rw=0 .0 83 .最高和最低残余峰分别为 0 .82和 -0 .48× 10 3 e-/nm3 . 展开更多
关键词 环状膦酸酐 合成 x射线晶体结构 反应机理 2 4-二叔丁基-6-甲氧基苯膦二硫化物 核磁共振磷谱 羰基反应
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SARS-CoV-2主蛋白酶的表达、纯化和一种新型晶体结构的研究
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作者 刘雪静 赵文聪 +7 位作者 高欣欣 陈思旭 张博涛 王君帅 李朝阳 温一帆 高靓 曹鹏 《生物医学》 2024年第2期229-239,共11页
新型冠状病毒SARS-CoV-2的主蛋白酶(Main Protease, Mpro),也称为3-糜蛋白酶样蛋白酶(3CLpro),在病毒复制的过程中发挥核心作用。Mpro的结构和功能在β-冠状病毒中相对保守,在人体内没有同源蛋白,因此是抗病毒药物开发的关键靶点。本研... 新型冠状病毒SARS-CoV-2的主蛋白酶(Main Protease, Mpro),也称为3-糜蛋白酶样蛋白酶(3CLpro),在病毒复制的过程中发挥核心作用。Mpro的结构和功能在β-冠状病毒中相对保守,在人体内没有同源蛋白,因此是抗病毒药物开发的关键靶点。本研究完成了SARS-CoV-2 Mpro的原核表达与纯化,获得具有高纯度和高均一性的蛋白质样品。利用气相扩散坐滴法开展了Mpro的结晶筛选,获得单晶体后将其浸泡在由谷胱甘肽包裹的金团簇纳米材料溶液中,成功解析了仅有第156位半胱氨酸结合一个金离子的一个新型X射线衍射晶体结构。结构分析发现,Mpro蛋白的Cys156结合金离子后Asp153~Cys156区域的构象发生了~0.6 Å的偏移,推测该构象变化进一步通过变构效应抑制Mpro的生物功能,为新冠病毒的纳米型抑制剂的研发提供了新的信息。 展开更多
关键词 SARS-CoV-2 Mpro 金团簇 蛋白质表达与纯化 x射线晶体结构
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人酪蛋白激酶1家族δ型蛋白的异源表达和纯化及晶体结构研究
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作者 李怡莹 姜文艳 +4 位作者 宋嘉宁 吕博强 曹鹏 龚勇 王娟 《河北师范大学学报(自然科学版)》 2025年第3期287-296,共10页
酪蛋白激酶1-δ型蛋白(casein kinase 1 isoform delta,CK1δ)是一个高度保守的丝氨酸/苏氨酸蛋白激酶,在众多细胞过程中发挥重要的调节作用.针对CK1δ蛋白的X射线晶体结构研究可以揭示激酶发挥功能的结构基础.本研究构建了人源CK1δ^(1... 酪蛋白激酶1-δ型蛋白(casein kinase 1 isoform delta,CK1δ)是一个高度保守的丝氨酸/苏氨酸蛋白激酶,在众多细胞过程中发挥重要的调节作用.针对CK1δ蛋白的X射线晶体结构研究可以揭示激酶发挥功能的结构基础.本研究构建了人源CK1δ^(1-293)原核表达载体pET28a(+)-His-CK1δ^(1-293),并完成了重组蛋白的诱导表达,经过镍亲和层析、透析酶切和凝胶过滤层析获得了高纯度、高浓度的CK1δ激酶结构域蛋白.使用多种结晶条件试剂盒和气相扩散坐滴法筛选获得了CK1δ^(1-293)蛋白的单晶体.经X射线衍射测定蛋白质晶体的衍射分辨率为2.5Å,空间群为P2_(1)2_(1)2_(1),晶胞参数为a=45.8Å,b=72.7Å,c=330.3Å,α,β,γ=90°.该晶胞参数与已知的CK1δ^(1-293)蛋白晶体结构相比均不相同,为一个全新的晶型.结构分析发现新晶型中具有独特结构特征,为CK1δ蛋白抑制剂的设计提供了新的信息. 展开更多
关键词 CK1δ蛋白 原核表达 蛋白纯化 x射线晶体结构解析
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Determination of Structure and Polarity of Si C Single Crystal by X-Ray Diffraction Technique 被引量:1
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作者 郑新和 渠波 +2 位作者 王玉田 杨辉 梁骏吾 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第1期35-39,共5页
Structure and polarity of the Si C single crystal have been analyzed with the four- circle X- ray diffraction method by a double- crystal diffractom eter.The hexagonal{ 10 15 } pole figure shows that this Si C sam pl... Structure and polarity of the Si C single crystal have been analyzed with the four- circle X- ray diffraction method by a double- crystal diffractom eter.The hexagonal{ 10 15 } pole figure shows that this Si C sam ple has a6 H modification.The difference between the integrated intensities m easured byω scan in the triple- axis diffraction set- up finds some convincing evidence that the surface is either a Si- terminated face or C- terminated face.The experi- mental ratios of| F( 0 0 0 L) | 2 / | F( 0 0 0 L) | 2 are in good agreem entwith the calculated ones after the dispersion cor- rections to the atomic scattering factors( L=6 ,12 and18,respectively) .Thus,this m easurem ent technique is con- venient for the application of the materials with remarkable surface polarity. 展开更多
关键词 Si C single crystal polarity hexagonal6 H scattering factor
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Crystal Structure of 8β-Hydroxyeremophil-7(11)-ene-12,8α(4β,6α)-diolide 被引量:3
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作者 Hui-qing Xue Hui-feng Xue +3 位作者 Biao Wu Han-qing Wang Xue-lei Xin Shui-xian Wu 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第6期519-522,共4页
8β-hydroxyeremophil-7(11)-ene-12,8α(4β,6α)-diolide was isolated from the Ligularia intermedia and characterized by MS, multi NMR and X-ray single crystal diffraction. Its crystal structure was determined as in... 8β-hydroxyeremophil-7(11)-ene-12,8α(4β,6α)-diolide was isolated from the Ligularia intermedia and characterized by MS, multi NMR and X-ray single crystal diffraction. Its crystal structure was determined as in a orthorhombic type, with space group P212121 with a=6.8519(5), b=10.7191(8), c=18.5942(14) A, V=1365.67(18) A,^3 Z=4, and the calculated density is 1.354 mg/m^3. F(000)=592, μ=0.101 mm^-1. 展开更多
关键词 Ligularia intermedia ISOLATION Crystal structure x-raty diffratction
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Synthesis and Crystal Structure of Methyl(7,7-Dimethyl-2-amino-4-(4-chlorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl)Carboxylate 被引量:2
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作者 WANGXiang-Shan SHIDa-Qing 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第6期597-600,共4页
The title compound methyl (7,7-dimemyl-2-amino-4-(4-chlorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl) carboxylate (C19H20ClNO4, Mr = 361.81) was synthesized and crystallized. The crystal belongs to tricl... The title compound methyl (7,7-dimemyl-2-amino-4-(4-chlorophenyl)-5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran-3-yl) carboxylate (C19H20ClNO4, Mr = 361.81) was synthesized and crystallized. The crystal belongs to triclinic, space group P 1 with a = 8.519(2), b = 10.346(2), c = 11.481(3) A, α = 108.16(1), β = 107.78(2), γ= 91.83(2)°, Z = 2, V = 906.5(3) A3, Dc = 1.326 g/cm3, μ(MoKα) = 0.234 mm-1, F(000) = 380, R = 0.0467 and wR = 0.1270 for 3142 observed reflections (I > 2σ(I)). X-ray analysis reveals that the C(7), C(8), C(9), O(1), C(10) and C(11) atoms form a six-membered ring which adopts a boat conformation. In the ring, the distances of C(8)-C(9) and C(10)-C(11) are 1.332(3) and 1.357(3) A, respectively, which indicates that they are C=C double bonds. Another six-membered ring (C(8)-C(9)-C(15)-C(14)-C(13)-C(12)) adopts the half-chair confonnation. In addition, there are intermolecular hydrogen bonds in the crystal structure. 展开更多
关键词 crystal structure benzo-[b]-pyran synthesis
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Photocycloaddition of (4-methyl-7-coumarinyl) Oxyacetic Acid Propanediol Diester and X-ray Crystal Structure of Product
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作者 杜大明 孟继本 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1995年第4期272-276,共5页
The photocycloaddition of (4-methyl-7-coumarinyl) oxyacetic acid propanediol diester 1 (C_27H_24O_10) in chloroform produced a single product 2 characterized to be syn head-tail. Crystal structure of 2 has been determ... The photocycloaddition of (4-methyl-7-coumarinyl) oxyacetic acid propanediol diester 1 (C_27H_24O_10) in chloroform produced a single product 2 characterized to be syn head-tail. Crystal structure of 2 has been determined by X-ray diffraction analysis. The crystal belongs to orthorhombic system, space group Pbca, with cell parameters a=10. 745(5), b= 13. 443(4), c=33. 358(9) A, V=4791 (5) A ̄3, M_r=508. 49,Z= 8, D_c=1. 41 g/cm ̄3, μ= 1. 015 cm ̄-1, F(000)=1064. The final R=0. 065 for 1587 observed reflections. Compound 2 has a large ring resulted from [2+2] photocycloaddition. The four-member ring of 2 has poor coplanarity, the two diagonal atoms of four-member ring are above the least-squares plane, and another diagonal atom couple is below the least-squares plane, the deviations of two couples are approximately equal. 展开更多
关键词 PHOTOCYCLOADDITION coumarin derivative crystal structure
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Computational Determination of the Binding Mode of α-Conotoxin to Nicotinic Acetylcholine Receptor
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作者 TABASSUM Nargis YU Rilei JIANG Tao 《Journal of Ocean University of China》 SCIE CAS 2016年第6期1027-1033,共7页
Abstract Conotoxins belong to the large families of disulfide-rich peptide toxins from cone snail venom, and can act on a broad spectrum of ion channels and receptors. They are classified into different subtypes based... Abstract Conotoxins belong to the large families of disulfide-rich peptide toxins from cone snail venom, and can act on a broad spectrum of ion channels and receptors. They are classified into different subtypes based on their targets. The a-conotoxins selectively inhibit the current of the nicotinic acetylcholine receptors. Because of their unique selectivity towards distinct nAChR subtypes, a-conotoxins become valuable tools in nAChR study. In addition to the X-ray structures of a-conotoxins in complex with acetyleholine-binding protein, a homolog of the nAChR ligand-binding domain, the high-resolution crystal structures of the extracellular domain of the al and a9 subunits are also obtained. Such structures not only revealed the details of the configuration of nAChR, but also provided higher sequence identity templates for modeling the binding modes of a-conotoxins to nAChR. This mini-review summarizes recent modeling studies for the determination of the binding modes of a-conotoxins to nAChR. As there are not crystal structures of the nAChR in complex with conotoxins, computational modeling in combination of mutagenesis data is expected to reveal the molecular recognition mechanisms that govern the interactions between a-conotoxins and nAChR at molecular level. An accurate determination of the binding modes of a-conotoxins on AChRs allows rational design of a-conotoxin analogues with improved potency or selectivity to nAChRs. 展开更多
关键词 Nicotinic acetylcholine receptor a-conotoxin acetylcholine binding protein DOCKING homology modeling moleculardynamics simulation mutational energy
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Synthesis and Characterization of New Palladium(ll) Complexes Containing 4,5-dimethyl-2,2'-bipyridine: X-ray Crystal Structure of Bis(4-methyl pyrdine)-4,5- dimethyl-2,2'-bipyridine palladium (11) Perchlorate
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作者 Bashir EI-Gnidi Abdulhafid M. Belazi R. D. Gillard 《Journal of Chemistry and Chemical Engineering》 2012年第8期673-681,共9页
New heteroleptic and homoleptic complexes of the type[Pd(4,5-dmbipy)C12], [Pd(4,5-dmbipy)L2], and [Pd(4,5-dimebipy)2]2+ (L = Pyridine or 4-methylpyridine(4-picoline), bipy = 2,2'-bipyridine, and 4,5-dimebip... New heteroleptic and homoleptic complexes of the type[Pd(4,5-dmbipy)C12], [Pd(4,5-dmbipy)L2], and [Pd(4,5-dimebipy)2]2+ (L = Pyridine or 4-methylpyridine(4-picoline), bipy = 2,2'-bipyridine, and 4,5-dimebipy = 4,5-dimethyl-2,2'-bipyridine) were synthesized and characterized by IH NMR and elemental analysis. The crystal structure of bis(4-methylpyridine)-4,5- dimethyl-2,2'-bipyridinepalladium(II)perchlorate [Pd(4,5-dmbipy)(4-pic)2](CIO4)2 was also determined by single crystal X-ray diffraction. This complex crystallized in the triclinic crystal system and space group PI with a = 9.562 (2), b = 11.326 (4), c = 15.0120 (10) A°; α = 70.940°, β= 77.60 (2), γ= 67.86 (2) and z = 4. The Pd (II) in square planar environment showed a small distortion towards tetrahedral through one coordinated bipyridine ring twisting with respect to the other. 展开更多
关键词 4 5-dimethyl-2 2'-bipyridine palladium(II) complexes single crystal.
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X-ray Study on the Ring-substituted Phthalocyanines:Crystal Structure of Metal Free 1,4,8,11,15,18,22,25-Octa-butyloxyphthalocyanine
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作者 WANG Jun-Dong HUANG Jin-LingCAI Jin-Wan CHEN Nai-Sheng(Department of Chemistry, Fuzhou University, and State Key Laboratory of Structural Chemistry,Fuzhou 350002, China) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第6期617-620,共4页
The crystal structure of 1,4,8,11,15,18,22,25-octa-butyloxyphthalocyanine was determined by X-ray diffraction methods. The crystal is of triclinic, space group P 1 with a = 14.0780(3), b = 14.3480(4), c = 17.0090(2) ... The crystal structure of 1,4,8,11,15,18,22,25-octa-butyloxyphthalocyanine was determined by X-ray diffraction methods. The crystal is of triclinic, space group P 1 with a = 14.0780(3), b = 14.3480(4), c = 17.0090(2) A, α = 72.156(2), β = 86.193(2), r= 73.655(2)°, C64H82N8O8, Mr = 1091.38, Z = 2, V = 3137.5(1) A3, Dc= 1.155 g/cm3, F(000) = 1172, μ(MoKα) = 0.077 mm-1, the final R = 0.0787 and wR = 0.2240 for 5795 observed reflections with I ≥ 2σ(I). The steric congestion between the neighboring butyloxy groups distorts the core of phthalocyanine into a saddle shape conformation. In the crystal lattice, molecules overlap to each other with π-π interaction but the extent of overlap is different along the three axial directions. 展开更多
关键词 PHTHALOCYANINE crystal structure
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Synthesis and Crystal Structure of 1,4-Bis(2-hydroxymethylphenyl)-1,4-dioxabutane
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作者 许兴友 刘清亮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第5期473-476,共4页
A new ligand 1,4-bis(2-hydroxymethylphenyl)-1,4-dioxabutane was synthesized by reducing 1,4-bis(2-formylphenyl)-1,4-dioxabutane with NaBH4 in absolute methanol solution. The crystal structure of the title compound C16... A new ligand 1,4-bis(2-hydroxymethylphenyl)-1,4-dioxabutane was synthesized by reducing 1,4-bis(2-formylphenyl)-1,4-dioxabutane with NaBH4 in absolute methanol solution. The crystal structure of the title compound C16H18O4 has been determined by single-crystal X-ray diffraction. The ligand crystallizes in the orthorhombic system, space group Pbcn with a = 13.777(1), b = 11.731(1), c = 9.076(8) ? V = 1466.8(2) ?, Mr = 274.30, Z = 4, F(000) = 548, Dc = 1.24 g/cm3, T = 293 K, m = 8.9 cm-1 and l = 0.71073 ? The structure was refined to R = 0.0324 and wR = 0.1025 for 1112 observed reflections with I > 2s(I). The two benzene rings are not on the same plane, and the dihedral angle between them is 60.6? The ligand has C2 symmetry axis which passes through the center of C(8)C(8a). The molecules are linked to each other by hydrogen bonding network to form supramolecular chain. The ligands connect to each other through the hydrogen bonds to form one-dimensional chains which further connect through the hydrogen bonds to form two- and three-dimensional structures. 展开更多
关键词 LIGAND SYNTHESIS crystal structure
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亨利·布拉格父子:为诺贝尔奖颁奖史刷新了两项记录 被引量:2
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作者 程民治 王向贤 《巢湖学院学报》 2010年第3期56-62,共7页
本文简要地介绍了共同摘取1915年度诺贝尔物理学奖桂冠的亨利?布拉格父子的人生简历和卓越的贡献,并揭示了他们辉煌的科学人生给人们所带来的深刻启示。
关键词 布拉格父子 诺贝尔物理学奖 x射线晶体结构分析 两项记录
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中国的国家科技奖励制度应向诺贝尔奖借鉴什么 被引量:1
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作者 本刊编辑部 张九庆 《中国科技论坛》 CSSCI 北大核心 2015年第1期1-1,共1页
大凡对诺贝尔奖有所了解的人都知道,很多获奖人获奖时年纪轻轻,原因是他们在更年轻时提出了重要理论或者得到了重要发现。一个大家熟悉的例子是,劳伦斯·布拉格因为X射线晶体结构的开创性工作,25岁时就和自己的父亲亨利·... 大凡对诺贝尔奖有所了解的人都知道,很多获奖人获奖时年纪轻轻,原因是他们在更年轻时提出了重要理论或者得到了重要发现。一个大家熟悉的例子是,劳伦斯·布拉格因为X射线晶体结构的开创性工作,25岁时就和自己的父亲亨利·布拉格一起登上了物理学的最高领奖台。 展开更多
关键词 诺贝尔奖 科技奖励制度 x射线晶体结构 借鉴 中国 布拉格 劳伦斯 物理学
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揭示植物在黑暗中变绿之谜
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作者 子周 《基因组学与应用生物学》 CAS CSCD 北大核心 2010年第3期587-587,共1页
东京大学生命科学院、立命馆大学生物科学与应用生物学、名古屋大学生物科学研究院以及大阪大学蛋白质研究所的研究人员共同合作,阐述了光独立的原叶绿素酸脂还原酶(Pchlide)X射线晶体结构,揭示了植物在黑暗中变绿之谜。该文章4月18... 东京大学生命科学院、立命馆大学生物科学与应用生物学、名古屋大学生物科学研究院以及大阪大学蛋白质研究所的研究人员共同合作,阐述了光独立的原叶绿素酸脂还原酶(Pchlide)X射线晶体结构,揭示了植物在黑暗中变绿之谜。该文章4月18日发表于《Nature》网络版,5月6日刊登在《Nature》杂志上。 展开更多
关键词 变绿 植物 《NATURE》 x射线晶体结构 东京大学 科学研究院 名古屋大学 生物科学
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钙通道的超级选择性
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《硅酸盐通报》 CAS CSCD 北大核心 2014年第1期230-230,共1页
“电压门控的钙”(CaV)通道具有显著选择性,可帮助Ca2+从细胞外介质(在其中Na+浓度比Ca2+浓度高70倍)中输入。CaV通道是怎样解决这一基本生物物理问题的仍不清楚。研究论文发表了全长度四聚体细菌NaV通道的几个x射线晶体结构,... “电压门控的钙”(CaV)通道具有显著选择性,可帮助Ca2+从细胞外介质(在其中Na+浓度比Ca2+浓度高70倍)中输入。CaV通道是怎样解决这一基本生物物理问题的仍不清楚。研究论文发表了全长度四聚体细菌NaV通道的几个x射线晶体结构,该通道是通过突变生成的。 展开更多
关键词 钙通道 x射线晶体结构 CA2+ 细胞外介质 电压门控 物理问题 论文发表 浓度比
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High-resolution 3D Structures Reveal the Biological Functions of Reoviruses 被引量:3
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作者 Xiaoming Li Qin Fang 《Virologica Sinica》 SCIE CAS CSCD 2013年第6期318-325,共8页
Viruses in the family Reoviridae are non-enveloped particles comprising a segmented double-stranded RNA genome surrounded by a two-layered or multi-layered icosahedral protein capsid.These viruses are classified into ... Viruses in the family Reoviridae are non-enveloped particles comprising a segmented double-stranded RNA genome surrounded by a two-layered or multi-layered icosahedral protein capsid.These viruses are classified into two sub-families based on their particle structural organization.Recent studies have focused on high-resolution three-dimensional structures of reovirus particles by using cryo-electron microscopy (cryo-EM) to approach the resolutions seen in X-ray crystallographic structures.The results of cryo-EM image reconstructions allow tracing of most of the protein side chains,and thus permit integration of structural and functional information into a coherent mechanism for reovirus assembly and entry. 展开更多
关键词 Non-enveloped virus Reoviruses Structural basis ASSEMBLY Cell entry
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Synthesis and Structural Characterization of [(C_2H_5)_4N][V^((V))O_2(OC_6H_3(OCH_3)CHNNCSNH_2)]·H_2O 被引量:1
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作者 周荫庄 金祥林 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第4期249-252,共4页
The reaction of tetraethylammonium metavanadate, (Et4N)VO3, with isovanillin semithiocarbazone(VSTC), HOC6H3(OCH3)CH=NNHCSNH2, in a mixed solvent of ethanol, water and DMSO yields the mononuclear dioxovanadate(... The reaction of tetraethylammonium metavanadate, (Et4N)VO3, with isovanillin semithiocarbazone(VSTC), HOC6H3(OCH3)CH=NNHCSNH2, in a mixed solvent of ethanol, water and DMSO yields the mononuclear dioxovanadate(V) complex, [(C2H5)4N][V(V)O2 (OC6H3- (OCH3)CHNNCSNH2)](H2O (C17H31N4O5SV, Mr = 454.5) and its single-crystal structure has been determined by X-ray diffraction. The crystal belongs to orthorhombic space group P212121 with unit cell parameters a = 12.940(3), b= 15.414(3), c = 10.703(2) ?, V = 2134.8(11) ?3, Z=4, Dcalc = 1.414 Kg/m3, ( = 0.597 mm-1, and F(000) = 960. The final agreement factors are R = 0.076 and Rw=0.096 for 1600 observed independent reflections with F ≥4.0((F). The structure revealed that the vanadium atom is bound to two terminal oxygen atoms and one tridentate donor ligand in a distorted square pyramidal arrangement. The sulphur-nitrogen-oxygen donor Schiff-base ligand in the thiol form rather than the thione form is coordinated to the vanadium via the mercapto sulphur, the (-nitrogen and the hydroxylate oxygen. 展开更多
关键词 vanadium(V) complex sulphur-oxygen-nitrogen donor Schiff-base isovanillin semithiocarbazone crystal structure
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Crystal structures and elastic properties of Ti(Cu,Pt)2 and Ti(Cu,Pt)3 phases 被引量:1
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作者 Wei-jing ZENG Kun HU +3 位作者 Hua-shan LIU Hai-long PENG Ge-mei CAI Zhan-peng JIN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第7期1839-1848,共10页
This paper focused on the crystal structures of two new ternary phases,Ti(Cu,Pt)2 and Ti(Cu,Pt)3,which were studied by X-ray powder diffraction data using Rietveld method.Electron probe microanalysis was used for samp... This paper focused on the crystal structures of two new ternary phases,Ti(Cu,Pt)2 and Ti(Cu,Pt)3,which were studied by X-ray powder diffraction data using Rietveld method.Electron probe microanalysis was used for sample composition examination.Elastic properties of these phases were further measured by nano-indentation,and meanwhile calculated with first-principle(FP)calculations.It is found that the crystal structure of Ti(Cu,Pt)2 is of orthorhombic cell space group Amm2(No.38)with structural prototype of VAu2.The resolved structure of Ti(Cu,Pt)3 is of tetragonal Al Pt3 type,belonging to the space group P4/mmm(No.123).The nano-indentation measurement and FP calculations show that the elastic modulus of Ti(Cu,Pt)2 increases firstly then decreases with Pt content,whereas that of Ti(Cu,Pt)3almost linearly increases with Pt content. 展开更多
关键词 Ti-Cu-Pt phase crystal structure x-ray diffraction first-principle calculations elastic properties
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One-dimensional Zigzag Chain Coordination Polymer [Zn(μ-phth)(imi)_2]_∞ Bridged by ο-Phthalato 被引量:1
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作者 刘庆燕 刘平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第5期509-512,共4页
The reaction of zinc carbonate with o-phthalic acid and imidazole in an aqueous-alcohol solution led to the formation of colorless crystals of [Zn(-phth)(imi)2]∞. Single-crystal X-ray analysis has revealed that the c... The reaction of zinc carbonate with o-phthalic acid and imidazole in an aqueous-alcohol solution led to the formation of colorless crystals of [Zn(-phth)(imi)2]∞. Single-crystal X-ray analysis has revealed that the complex crystallizes in a monoclinic system, space group Pn with a = 8.394(2), b = 9.976(3), c = 9.959(3) ? ?= 104.409(4)? V = 807.6(4) ?, Z = 2, C14H12N4O4Zn, Mr = 365.65, Dc = 1.504 g/cm3, ?= 1.544 mm-1, F(000) = 372, the final R = 0.0466 and wR = 0.1171 for 1834 reflections with I >2(I). The complex displays a zigzag infinite chain structure in which each zinc (Ⅱ) center is coordinated by two oxygen atoms and two nitrogen atoms to generate a ZnN2O2 distorted tetrahedral geometry. The neighboring zinc atoms are bridged by the o-phthalate ligand. Each chain is linked by hydrogen bonds with its neighbors to form a three-dimensional coordination polymer. 展开更多
关键词 zinc (Ⅱ) complex o-phthalate crystal structure chain coordination polymer
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