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61.
62.
Marina S. Fonari Yurii A. Simonov Gabriele Bocelli Eduard V. Ganin Wen-Jwu Wang Sergei M. Pluzhnik-Gladyr Vyacheslav V. Tkachyuk Sergei A. Kotlyar Gerbert L. Kamalov 《Journal of inclusion phenomena and macrocyclic chemistry》2008,61(3-4):367-375
Four novel complexes of 2,4-dithiouracil (pyrimidine-2,4(1H,3H)-dithione, DTU) with 18-membered benzo- and dibenzo-crown ethers were synthesized in approximately the same conditions and studied by single crystal diffraction. Hydrogen bonding was observed to be the most important for the complexation in the solid state but π–π interactions also contribute to it. The crystalline monohydrates of the 1:1:1 stoichiometry are recorded for 4-bromo- and 4-nitrobenzo-18-crown-6 (complexes 1 and 2), while complexes with [2.4]dibenzo- and thia[1.5]dibenzo-18-crown-6 (complexes 3 and 4) represent anhydrous adducts of the 2:2 ratio. The crystal structures reveal three supramolecular structural motifs: the alternative chain for the ternary complex 1 and two types of capsules for complexes 2?4 where the DTU dimers are encapsulated inside the space restricted by two crown molecules. 相似文献
63.
Yu. M. Chumakov L. G. Paladi B. Ya. Antosyak Yu. A. Simonov V. I. Tsapkov G. Bocelli A. P. Gulea D. Ginju S. A. Palomares-Sanchez 《Crystallography Reports》2011,56(2):260-264
Nitrato-(2-hydroxy-5-nitrobenzaldehydo)(2,2′-bipyridyl)copper (I) and nitrato-(2-hydroxybenzaldehydo)(2,2′-bipyridyl)copper (II) were synthesized and characterized by X-ray diffraction. The coordination polyhedron of the central copper atom in complex
I can be described as a distorted tetragonal pyramid whose base is formed by the phenol and carbonyl oxygen atoms of the monodeprotonated
2-hydroxy-5nitrobenzaldehyde molecule and the nitrogen atoms of the 2,2′-bipyridyl ligand and whose apex is occupied by the
oxygen atom of the nitrato group. In the crystal structure, complexes I are linked by the acido ligands and the NO2 groups of the aldehyde molecule into infinite chains. In complex II, the central copper atom is coordinated by 2-hydroxybenzaldehyde, 2,2′-bipyridyl, and the nitrato group, resulting in the
formation of centrosymmetric dimers. The coordination polyhedron of the central copper atom can be described as a bipyramid
(4 + 1 + 1) with the same base as in complex I. The axial vertices of the bipyramid are occupied by the oxygen atom of the nitrato group and the bridging phenol oxygen
atom of the adjacent complex related to the initial complex by a center of symmetry. In the crystal structure, complexes II are hydrogen bonded into infinite chains. 相似文献
64.
K.?Balasubramani D.?Kalaivani R.?Malarvizhi R.?Subbalakshmi P.?Thomas MuthiahEmail author G.?Bocelli A.?Cantoni 《Journal of chemical crystallography》2011,41(6):767-773
Abstract
The title compounds C19H18N3O9 −·C6H16N+ (I) [triethylammonium 2-benzyl-2-ethoxycarbonyl-3-oxo-8,9-dinitro-bicyclo [3.3.1] non-7-en-6-nitronate] and C19H17N4O11 −·C6H16N+ (II) [triethylammonium 2(4-nitrophenylmethyl)-2-ethoxycarbonyl-3-oxo-8,9-dinitro-bicyclo [3.3.1] non-7-en-6-nitronate] crystallize in monoclinic crystal system with P2 1 /c space group. In compounds I and II, the bicyclo [3.3.1] nonane has chair–envelope conformation. The crystal structure of compound (I) is stabilized by N–H⋯O, N–H⋯N hydrogen bonds. In both the crystal structures weak C–H⋯O hydrogen bond is observed. Both compounds adopt chair–envelope conformation. An examination of puckering parameters, torsion angles and model (Dreiding) of the title compounds clearly indicates that the ring A has slightly distorted chair conformation and ring B has slightly distorted envelope conformation. 相似文献65.
Yu. M. Chumakov V. I. Tsapkov B. Ya. Antosyak L. G. Popovschi G. Bocelli A. P. Guly S. A. Palomares-Sanchez 《Crystallography Reports》2012,57(2):235-240
Nitrato-4-bromo-2-[(2-hydroxyethylimino)methyl]phenolatoimidazolecopper and nitrato-4-chloro-2-[(2-hydroxyethylimino)methyl]phenolatoimidazolecopper
were synthesized and studied by X-ray diffraction. The crystals are isostructural. The coordination polyhedron of the copper
atom can be described as a distorted square pyramid whose basal plane is formed by the phenolic and alcoholic oxygen atoms
and the nitrogen atom of the monodeprotonated tridentate azomethine molecule and the imidazole nitrogen atom. The apex of
the copper polyhedron is occupied by the oxygen atom of the nitrato group. The complexes are linked together by hydrogen bonds
with the participation of the nitrato groups to form a three-dimensional framework. 相似文献
66.
Annamalai Subashini Madhukar Hemamalini P. Thomas Muthiah Gabriele Bocelli Andrea Cantoni 《Journal of chemical crystallography》2009,39(2):112-116
Abstract The structure of the title compound (C17H15N3O4S)2 the schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was elucidated by H1, C13 NMR, UV–VIS and IR spectroscopic techniques. The X-ray structure was determined in order to establish the conformation of
the molecule. The compound crystallizes in the triclinic space group P-1, with a = 11.419(1), b = 11.426(0), c = 13.316(1) ?, α = 71.94(2), β = 89.79(1), γ = 89.14(2)° and Z = 4. Two benzene rings and azomethine group are practically coplanar, as a result of intramolecular hydrogen bonds involving
the hydroxy O atom and azomethine N atom. The component species further interact via N–H···N and C–H···O hydrogen bonds and
π–π stacking interactions.
Index Abstract The title compound (C17H15N3O4S)2, Schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was synthesized by the condensation of 4-amino-N-(5-methyl-3-isoxazolyl) benzene sulfonamide (SMZ) and 2-hydroxy benzaldehyde (SA). Its structure was confirmed by single
crystal X-ray diffraction analysis.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
67.
68.
69.
Sergei A. Kotlyar Marina S. Fonari Yurii A. Simonov Gabriele Bocelli Oleg V. Shishkin Svetlana V. Shishkina Vyacheslav V. Tkachuk Ruslan Ya. Grygorash Gerbert L. Kamalov 《Journal of inclusion phenomena and macrocyclic chemistry》2005,52(1-2):75-84
The interaction of the amidosulfuric acid NH
3
SO
3
with 15 distal and proximal dibenzocrown ethers, including diphenyloxide, diphenylsulfide and biphenyl ones leads to the stable (1:1) complexes only in the case of [2.4]- and [1.5]dibenzo-18-crown-6 and biphenyl-20-crown-6. According to the data of the X-ray analysis, in the two last adducts the amidosulfuric acid coordinates to hexadentate crown ethers in a zwitterion form through a near-ideal ‘tripod’ arrangement to alternate crown oxygen atoms. The conformations of crown molecules are different in complexes and in initial macrocyclic ligands.This revised version was published online in July 2005 with a corrected issue number. 相似文献
70.
M. Saravanan B. Arul Prakasam K. Ramalingam G. Bocelli A. Cantoni 《无机化学与普通化学杂志》2005,631(9):1688-1692
Three new transition metal complexes [Zn(bipyrtds)I2]( 1 ), [Cd(bipyrtds)I2] ( 2 ) and [Hg(pipdtc)I]( 3 ) (where bipyrtds = bipyrrolidine thiuamdisulfide and pipdtc = piperidinecarbodithioate) were prepared by the reaction of the corresponding biscarbodithioates with iodine and were characterized by elemental analysis, IR and NMR spectra. The structures of all the three complexes were determined by single crystal X‐ray crystallography. Compounds 1 and 2 contain four coordinated metal atoms and both ZnII and CdII complexes are isostrucutral. Interestingly, complex 3 was found to contain effectively four coordinated mercury atom as a dimer with a relatively long Hg‐S (3.084Å) bond. The IR studies are in keeping with the observed thioureide distances. 1H NMR spectra of 1 and 2 show clear differences in environments of α‐ and β‐CH2 protons. However, in 1 a broad signal was observed at 4.02 ppm for α‐protons and a multiplet at 2.10 for β‐protons. For 2 , two triplets appeared at 4.26 and 4.03 ppm for α‐protons and two quintets appeared in the range of 2.18 and 2.28 ppm for β‐protons. Complex 3 gave three sets of signals. Variation of stereochemical environment with respect to α and β protons of the rings is very clearly observed in the NMR spectra. 相似文献