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961.
Abstract The crystal structure of N′-(6-chloropyridin-3-formyl)-N-t-butyl urea, C11H14ClN3O2, has been established, and which belongs to monoclinic crystal system, space group Pn with unit cell dimensions a = 9.335(3) ?, b = 12.715(3) ?, c = 21.813(6) ?, β = 95.417(6)°, V = 2577.6(12) ?3 and Z = 8. An intramolecular N–H···O hydrogen bond forms a six-membered ring in the central part of the molecule. Both two N–H
atoms of single unit participate in intermolecular hydrogen bonds and an intramolecular hydrogen bond, respectively.
Index Abstract The crystal structure ofN′-(6-chloropyridin-3-formyl)-N-t-butyl urea, C11H14ClN3O2, has been established, and which belongs to monoclinic crystal system withZ = 8, space group Pn.
相似文献
962.
Abstract A new dinuclear hydrated nickel(II) tartrate has been isolated and structurally characterized by single-crystal X-ray diffraction.
The title compound formulated as [Ni4(C4H4O6)4(H2O)8](EtOH)0.5(H2O)10.25 (C17H55.5Ni4O42.75) crystallizes in monoclinic system, space group P2(1)/c with a = 13.684(5), b = 17.143(6), c = 18.586(6) ?, β = 96.638(6)°, V = 4331(3) ?3, Z = 4. The unit cell contains two crystallographic independent dimeric units of [Ni2(C4H4O6)2(H2O)4] without significant structural difference, half of menthol molecule and ten and a quarter packing water molecules. In each
dimeric unit, one (R,R)-tartrato dianion chelates two Ni(II) ions by the use of two hydroxy oxygen and two carboxyl oxygen atoms as donor atoms,
and another tartrato dianion chelates the same pair of Ni(II) cations in the same way. Each Ni(II) atom is six-coordinated
by six O atoms from two tartrate units and two water molecules.
Index Abstract The crystal structure of complex [Ni4(C4H4O6)4(H2O)8](EtOH)0.5(H2O)10.25 contains two crystallographic independent dimeric units of [Ni2(C4H4O6)2(H2O)4] without significant structural difference. In each dimeric unit, one (R,R)-tartrato dianion chelates two Ni(II) ions by the use of two hydroxy oxygen and two carboxyl oxygen atoms as donor atoms,
and another tartrato dianion chelates the same pair of Ni(II) cations in the same way.
相似文献
963.
Abstract The zinc(II) complex with 2-(2-hydroxyphenyl)benzimidazole, namely [Zn(2-(2-hydroxyphenyl)benzimidazolate)2]·C2H5OH (1 · C2H5OH) has been synthesized and characterized by X-ray crystallography and photoluminescent analysis. The complex crystallizes
in monoclinic space group P21/c with cell parameters a = 10.156(1) ?, b = 25.771(3) ?, c = 9.674(1) ?, α = 90°, β = 103.641(2)°, γ = 90°, Z = 4, V = 2460.4(4) ?3. The central Zn(II) is four-coordinate and has a tetrahedral geometry. The steady-state and time-resolved photoluminescent
spectra for the title compound have also been studied. The emission property can be ascribed to ligand-centered charge-transfer
transition (LCCT) with π → π* property.
Index Abstract
A new co-crystal of Zn(II) complex of 2-(2-hydroxylphenyl)benzimidazole with ethanol solvate has been prepared, characterized
by X-ray crystallography and fluorescent studies.
相似文献
964.
Alexander Hübner Daniel Strobusch Hans-Wolfram Lerner Michael Bolte 《Journal of chemical crystallography》2008,38(12):953-957
Abstract The crystal structure of the title compound, C30H42O12Zn3, originally determined from untwinned crystals (Bennett et al. Acta Cryst B 24:904, 1968) has been redetermined from twinned
crystals. The effect of the twinning is that additional reflections appear in the diffraction pattern leading to a unit cell
with a too long c-axis in which the structure cannot be solved. Thus, for a successful structure solution the correct unit cell has to be found
and for refinement the twinning has to be taken into account. The central Zn atom is located on a twofold rotation axis. It
is hexacoordinated in a distorted octahedral mode, whereas the coordination geometry of the two terminal Zn atoms is distorted
trigonal bipyramidal.
Index Abstract The crystal structure of the title compound, Zinc(II) acetylacetonate trimer, has been redetermined from twinned crystals.
For a successful structure solution the correct unit cell had to be found and for refinement the twinning had to be taken
into account. The central Zn atom is located on a twofold rotation axis. It is hexacoordinated in a distorted octahedral mode,
whereas the coordination geometry of the two terminal Zn atoms is distorted trigonal bipyramidal.
An erratum to this article can be found at 相似文献
965.
Abstract The single crystal of the title compound (C15H13N3O3S) with two conformational isomers was obtained from the solution of the title compound dissolved in the N,N-dimethylformamide (DMF) by slow evaporation at room temperature. The crystal is triclinic, space group P-1 with a = 10.418(2), b = 10.758(2), c = 14.494(3) ?, α = 71.07(3), β = 81.56(3), γ = 85.61(3)o, V = 1519.2(5) ?3, Z = 2, C30H26N6O6S2, D
c
= 1.379 g/cm3, μ(MoKα) = 0.229 mm−1, S = 0.994, F(000) = 656, R = 0.0688 and wR = 0.1695. In the unit cell, there are two independent molecules having only slightly different bond lengths and angles, but
the corresponding dihedral angles of the two molecules are different. Intermolecular N–H···S and N–H···O hydrogen bonds forming
R
2
2(8) and R
2
2(12) rings, respectively, link the molecules into ribbons.
Index Abstract In the unit cell, there are two independent molecules having only slightly different bond lengths and angles between them,
but different corresponding dihedral angles.
相似文献
966.
Qian Yang Bing-Yu Zhang Wei-Dong Ye Jian-Yong Yuan Duan-Jun Xu Jing-Jing Nie 《Journal of chemical crystallography》2008,38(9):659-661
Abstract The title compound (common name eplerenone), C24H30O6, is an aldosterone receptor antagonist. From the isopropyl acetate solution the compound crystallizes in monoclinic space
group P 21 with a = 8.811(1) ?, b = 11.250(1) ?, c = 11.079(1) ?, β = 93.822(12)°, Z = 2. The molecule contains three six membered rings, two five membered rings and one three membered ring. Both five membered
rings display envelope conformation, whereas three six membered rings show different conformation: chair, half-chair and envelope.
In the crystal the eplerenone molecules link to one another via intermolecular weak C–H···O hydrogen bonding to form the smaller
cavity of 12.0(1) ?3 between eplerenone molecules, no solvent molecule filled in this cavity.
Index Abstract In the title molecule three six-membered rings show different conformation. Weak C–H···O hydrogen bonding links adjacent molecules
to form the small cavity 12.0(1) ?3, no solvent molecule filled in the cavity.
相似文献
967.
Tarun Kumar Misra Jack Cheng Tian-Huey Lu Fen-Ling Liao Chung-Sun Chung 《Journal of chemical crystallography》2008,38(10):801-806
Abstract A new isomer of [Ni(tet-a)]2+ (assigned as γ-isomer) (tet-a = C-meso-5,5,7,12,12,14−hexamethyl-1,4,8,11-tetraazacyclotetradecane), which is found in the complex of trans-γ-[Ni(tet-a)(NCS)2], has been isolated from the reaction of β-[Ni(tet-a)](ClO4)2 with NaSCN in a mixture of MeOH–H2O (1:1, v/v) solution and characterized by X-ray crystallography. The complex crystallizes in orthorhombic Pca2(1) space group with the crystal cell parameters of a = 12.5787(10) ?, b = 11.6834(10) ?, c = 15.4019(12) ?, V = 2263.5(3) ?3, and Z = 4. The crystal structure shows that the complex is noncentrosymmetric. The conformations of the six-asymmetric centers
are assigned as 1R,4R,8S,11S,7R,14S or 1S,4S,8R,11R,7S,14R (Trans-III). The coordination polyhedron around the nickel atom is axially elongated octahedron with an N6 chromophore. The association of the complex units through N(3)–H···S(1) (2.665 ?) hydrogen bonding interactions leads one-dimensional
hydrogen bonded network along c-axis.
Index Abstract A new isomer of Ni(tet-a)2+, which is assigned as γ-isomer, in the complex of trans-γ-[Ni(tet-a)(NCS)2] has been synthesized, isolated and characterized by X-ray crystallography. The complex units form a one-dimensional self-assembly
hydrogen bonded network.
相似文献
968.
Xiu-rong Li Zhi-hui Zhang Xiu-feng Liu Hong Gao Xiang-nan Zhang Zhi-jin Fan 《Journal of chemical crystallography》2008,38(10):781-786
Abstract Two new complexes, [Cu(L)2(CH3OH)] · (ClO4)2 (1) and [Cu(L)2(H2O)] · (NO3)2 (2), have been synthesized and their crystal structures have been determined by X-ray analysis, where L = 3-(3,5-bimethylpyrazole-yl)-6-chloro-pyridazine].
The complex 1 crystallizes in the monoclinic, space group C2/c, and the coordination configuration of copper (II) is better described as trigonal pyramidal geometry with four N atoms from
L and one Omethanol. The coordination configuration of 2 is quite similar to that of 1 except Owater instead of Omethanol. The intermolecular hydrogen bonds link the repeat units and extend the molecules to multinuclear structures in both compounds.
The spectral properties of the title compounds have been studied and discussed. Furthermore, the antibacterial activities
of the title compounds have been detected, the results indicate that the ligands and two copper(II) complexes exhibit certain
fungicidal activities again several bacteria.
Index Abstract Two new complexes, [Cu(L)2(CH3OH)]·(ClO4)2 (1) and [Cu(L)2(H2O)]·(NO3)2 (2), have been synthesized and their crystal structures
have been determined by X-ray analysis, where L= 3-(3,5-bimethylpyrazole-yl)-6-chloro-pyridazine. The intermolecular hydrogen
bonds extend the molecules to multinuclear structures in both compounds.
相似文献
969.
Hua Fang Mei Juan Fang Rui Zao Yi Yu Fen Zhao 《Journal of chemical crystallography》2008,38(10):761-764
Abstract The title compound, C14H23O5P, was synthesized by the reaction of 4-methoxybenzaldehyde and diisopropyl phosphite. Its structure was determined with X-ray
crystallographic, NMR, MS, and elemental analysis (EA) techniques. The crystal belongs to monoclinic, space group P 21/n with the following crystallographic parameters: a = 10.529 (2) ?, b = 8.424 (2) ?, c = 19.448 (4) ?, α = 90°, β = 105.2 (3)°, γ = 90°, μ = 0.180 mm−1, V = 1664.1 (6) ?3, Z = 4, Dx = 1.207 mg/mm3, F (000) = 648, T = 293 (2) K, 2.00° ≤ θ ≤ 25.50°. The final residual factor is 0.049 for 1933 reflections with I > 2σ (I). Crystal packing is stabilized by interatomic hydrogen bond interactions between the doubly bonded phosphoryl O atom and
the hydroxyl H atom which link the molecules into chains along the [011] plane of the unit cell.
Index Abstract The title compound, diisopropyl hydroxy(4-methoxyphenyl)methylphosphonate, was synthesized by the reaction of 4-methoxybenzaldehyde
and diisopropyl phosphite. Its structure was determined with X-ray crystallographic, NMR, MS, and elemental analysis (EA)
techniques. Crystal packing is stabilized by interatomic hydrogen bond interactions between the doubly bonded phosphoryl O
atom and the hydroxyl H atom which link the molecules into chains along the [011] plane of the unit cell.
相似文献
970.
Abstract The salt tris-(N–N dimethyl benzylammonium)-hexachlorobismuthate(III) crystallizes in the triclinic system P1 with unit cell parameters: a = 9.0300(12), b = 9.9220(3), c = 19.575(2) ?, α = 79.955(5), β = 89.952(2), γ = 88.108(6)°, V = 1726.0(3) ?3, Z = 2. The examination of the structure shows an alternate stacking of inorganic layers of hexachlorobismuthate(III) anions
and organic layers of [C6H5CH2NH(CH3)2]+ cations parallel to the a-axis. The cohesion forces of the packing of N–N dimethyl benzylammonium units in the layer and between two adjacent layers are provided by hydrogen bonds (N–H⋯Cl) and van
der Waals contacts.
Index Abstract The examination of the structure shows a layer arrangement parallel to the a-axis: planes of octahedral anions [BiCl6]3− alternate with planes of [C6H5CH2NH(CH3)2]+ cations (Fig. 3). The cohesion forces of the packing of the N–N dimethyl benzylammonium units in the layer and between two adjacent layers are provided by hydrogen bonds (N–H⋯Cl) and van
der Waals contacts.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献