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531.
Jiang‐Lin Fang Wei Huang Suchada Chantrapromma S. Shanmuga Sundara Raj Ibrahim Abdul Razak Hoong‐Kun Fun Shao‐Hua Gou Hong‐Sen Wang 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):1429-1430
A donor–acceptor compound, diaqua‐1κO,2κO‐[μ‐11,23‐dimethyl‐3,7,15,19‐tetraazatricyclo[19.3.1.19,13]hexacosa‐1(25),2,7,9,11,13(26),14,19,21,23‐decaene‐25,26‐diolato‐1κ4N3,N7,O25,O26:2κ4N15,N19,O25,O26]dizinc(II) diperchlorate bis(8‐methylquinoline) ethanol disolvate, [Zn2(C24H26N4O2)(H2O)2](ClO4)2·2C10H9N·2C2H6O, obtained by the reaction of a dinuclear zinc(II) complex of a Robson macrocycle (acceptor) and 8‐methylquinoline (donor), lies about an inversion centre and the coordination about the unique Zn atom is a distorted square pyramid. The fifth coordination site is occupied by the water molecule, Zn—O = 2.016 (2) Å, and the average macrocyclic Zn—O and Zn—N distances are 2.059 (6) and 2.059 (3) Å, respectively. 相似文献
532.
Ishankhodzhaeva M. M. Kadyrova Sh. A. Talipov S. A. Ibragimov B. T. Fun Kh. K. Sundara Razh S. S. Parpiev N. A. 《Russian Journal of General Chemistry》2001,71(7):1066-1069
Results of a single-crystal X-ray diffraction study of the complex of zinc(II) acetate with 2-amino-5-ethyl-1,3,4-thiadiazole were presented. The coordination polyhedron of the complex has a distorted tetrahedral configuration with nitrogen atoms of the two 2-amino-5-ethyl-1,3,4-thiadiazole molecules and oxygen atoms of the two acetate ions coordinated to the central ion. 相似文献
533.
Pan
e Naumov Gligor Jovanovski Sheng‐Zhi Hu Il‐Hwan Suh Ibrahim Abdul Razak Suchada Chantrapromma Hoong‐Kun Fun Seik Weng Ng 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1016-1019
The short carbonyl bond in the title compound, [Cu2(C7H4NO3S)4(C3H4N2)4] [Liu, Huang, Li & Lin (1991). Acta Cryst. C 47 , 41–43], is an artifact of disorder in the isothiazol‐3(2H)‐one 1,1‐dioxide part of the 1,2‐benzisothiazol‐3(2H)‐one entity. In the present redetermination, all bond dimensions in the centrosymmetric dinuclear molecule are normal. The five‐coordinate Cu atom shows trigonal–bipyramidal coordination. Hydrogen bonds from the imidazole donor ligand link adjacent molecules into a two‐dimensional layer structure. 相似文献
534.
制备4,4-连吡啶基二卤加和物[MX2(4,4′-bipy)]n仍然有较大困难.这类化合物数量不多且已报道的多为难处理的微晶材料.本文在室温下通过简单的操作合成了新的碘化汞连吡啶乙烷加和物[HgI2(bpea)]nox-射线单晶衍射分析表明其中的汞原子通过与两个碘原子以及吡啶乙烷的两个氮原子配位形成扭曲的四面体构型.每个HgI2单元由bpea桥连形成锯齿状链.其非线性光学性质用8-纳秒激光在532nm波长进行了研究.该化合物相对于入射光表现为一定的光学吸收和强的自聚焦效应,其三阶非线性吸收系数α2=1.1×10-11m@W-1,折射系数n2=5.29×10-188m2@w-1. 相似文献
535.
Shyamaprosad Goswami Avijit Kumar Das Abhishek Manna Anup Kumar Maity Hoong-Kun Fun Ching Kheng Quah Partha Saha 《Tetrahedron letters》2014
A ratiometric fluorescent turn-on probe for fluoride ion, based on modulation of the excited-state intramolecular proton transfer (ESIPT) process by chemodosimetric desilylation pathway is reported. The probe SNBT (silyl protected hydroxynaphthalene benzothiazole moiety) shows a significant increase of ratiometric absorption band at 440 nm and emission band at 477 nm by the deprotection of fluoride mediated silyl bond cleavage in CH3CN–H2O (8/2, v/v, 25 °C). The test strips based on SNBT and F− are fabricated, which can act as a convenient and efficient F− test kits. Furthermore, the biological application shows that it can be very useful as a selective fluoride probe in the fluorescence imaging of living cells. 相似文献
536.
537.
Xi‐Rui Zeng S. Shanmuga Sundara Raj Hoong‐Kun Fun Jing‐Lin Zuo Xiao‐Zeng You 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):941-942
In the title complex, [RuCl2(C16H36N4)]I3, the overall symmetry of the centrosymmetric cation is approximately C2h and the I anions are slightly asymmetric. The I?I distance is 4.313 (1) Å. The cations and the linear anions are arranged in alternate layers and thus form the intercalating structure. 相似文献
538.
John RP Sreekanth A Prathapachandra Kurup MR Usman A Ibrahim AR Fun HK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(6):1349-1358
The spectral studies and structure of a ternary complex of copper(II) with 2-hydroxyacetophenone 3-hexamethyliminylthiosemicarbazonate (L(2-)) and 1,10-phenanthroline (phen) are reported. The thiosemicarbazone binds to the metal as a dianionic ONS-donor (L(2-)) ligand, and forms a complex of the stoichiometry [CuLphen]. The copper(II) complex was characterized by IR and UV/Vis spectroscopies, as well as by solid state room-temperature magnetic susceptibility. Spin Hamiltonian and bonding parameters of the compound are calculated from the EPR spectra. Computer simulation of EPR spectrum in DMF at 77 K aided the calculation of magnetic and bonding parameters of the compound. The structure of the compound is solved by single crystal X-ray diffraction. The geometry around copper is distorted square pyramidal. 相似文献
539.
Zhang Ze Liu Qing-Liang Yang Jia-Xiang Wu Jie-Ying Tian Yu-Peng Jin Bao-kang Fun Hoong-Kun Chantrapromma Suchada Usman Anwar 《Transition Metal Chemistry》2003,28(8):930-934
The title complex [Mn2(phen)4(FCA)2](ClO4)2·H2O (1) (FCA = dianion of 3-ferrocenyl-2-crotonic acid, phen = 1,10-phenanthroline) has been prepared, and its structure determined by single crystal X-ray diffraction analysis. The structure consists of a dinuclear cation [Mn2(phen)4(FCA)2]2+, non-coordinated perchlorate anions and a water molecule. The two MnII ions are separated by 4.374 Å in the cation and are dicarboxylate-bridged by carboxylate ligands containing ferrocenyl units. Each FCA is bound to two MnII ions through carboxylate oxygens with the syn–anti bridging mode. The MnII ion is coordinated in an octahedral N4O2 geometry by two chelate phen ligands and two -carboxylate oxygen atoms. Electrochemical properties of (1) are discussed. 相似文献
540.
Hai‐Liang Zhu Xiu‐Ying Liu Xian‐Jiang Wang Feng Yang Anwar Usman Hoong‐Kun Fun 《无机化学与普通化学杂志》2003,629(11):1986-1990
Three polymeric silver(I) complexes with terephthalate anions as counterions or ligands, [Ag(pren)]2(tp)·2H2O ( 1 ), [Ag(en)][Ag(μ2‐tp)]·H2O ( 2 ), and [Ag2(μ4‐tp)(apy)2] ( 3 ) (where pren = 1, 2‐propylenediamine, tp =terephthalate dianion, en = ethylenediamine, and apy = 2‐aminopyridine) were synthesized and characterized by X‐ray single crystal analysis and infrared spectroscopy. 1 crystallizes in the monoclinic space group P211/c with a = 11.3221(5), b = 7.1522(3), c = 14.8128(5)Å, V = 1015.77(7)Å3, β = 122.132(2), and Z = 2. 2 crystallizes in the orthorhombic space group Pnma with a = 9.6144(6), b = 11.3465(7), c = 11.4810(7)Å, V = 1252.5(1)Å3, and Z = 4. 3 crystallizes in the monoclinic space group P21/n with a = 8.2003(5), b = 5.8869(4), c = 18.3769(11)Å, β = 92.593(1), V = 886.2(1)Å3, and Z = 4. Terephthalate dianions are not coordinated to the metal atoms in 1 , but act as a μ2‐bridging ligand in 2 and as a μ4‐bridging ligand in 3 . 相似文献