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991.
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
992.
Tamboura Farba Bouyagui Gaye Mohamed Nedelec Jean Marie Mentre Olivier 《Journal of chemical crystallography》2008,38(6):471-474
Abstract The copper complex [Cu(C23H27Br2N4O2)(H2O)(NO3)]2 was synthesized and characterized by X-ray diffraction. The complex crystallizes in the triclinic system with space group
P-1, lattice parameters: a = 13.2293(18) (?), b = 14.184(20) (?), c = 16.522(23) (?), α = 91.923(2)°, β = 111.777(2)°, γ = 111.259(2)°, V = 2632.0(6) ?3, Z = 4, D
c
= 0.88 Mg m−3. In the title compound [Cu(C23H27Br2N4O2)(H2O)(NO3)]2, the coordination polyhedron of the Cu atom is a square-planar environment. The structure consists of mononuclear units in
which the copper(II) ions are linked in the plane by N, N′ iminato and O, O′ phenoxo atoms. In addition the crystal lattice
contains one water molecule per unit.
Graphical Abstract Dissymmetric ligand was efficiently synthesized and used to prepfsare a copper(II) complex which was characterized by X-ray
diffraction
相似文献
993.
Wesley H. Monillas Glenn P. A. Yap Klaus H. Theopold 《Journal of chemical crystallography》2009,39(7):535-538
Abstract Addition LiNHPh to a [(NacNac)Cr(μ-I)]2 [NacNac = 2,4 pentane-N-N′-bis(2,6-diisopropylphenyl) ketiminato] in THF yields a dimeric anilido complex, 1, that crystallizes in P21/n with unit cell parameters a = 13.390(2) ?, b = 26.298(5) ?, c = 21.326(4) ?, β = 93.905(4)°, V = 7492(2) ?3 and Z = 4. The same reaction in the presence of aniline yields a monomeric anilido complex, 2, with a coordinated aniline molecule. Complex 2 crystallizes in P2
1
/c with unit cell parameters a = 28.530(5) ?, b = 10.8116(18) ?, c = 26.492(5) ?, β = 115.685(3)°, V = 7364(2) ?3 and Z = 8. Addition of aniline to isolated 1 yields 2. Addition of LiNPh2 to [(NacNac)Cr(μ-I)]2 in THF yields a monomeric complex that crystallizes in P21/n with the unit cell parameters a = 11.152(6) ?, b = 23.820(12) ?, c = 17.915(9) ?, β = 106.223(9)°, V = 4569(4) ?3 and Z = 4. All complexes have been spectroscopically and structurally characterized.
Graphical Abstract Addition of LiNHPh or LiNPh2 to [(NacNac)Cr(μ-I)]2 yields a dimeric or a monomeric complex whereas addition of LiNHPh in the presence of aniline yields the monomeric anilido
complex.
相似文献
994.
S. Naveen C. S. Ananda Kumar S. B. Benaka Prasad K. Vinaya M. A. Sridhar J. Shashidhara Prasad K. S. Rangappa 《Journal of chemical crystallography》2009,39(6):395-398
Abstract The title compound 1-benzhydryl-4-(toluene-4-sulfonyl)-piperazine was synthesized and the structure was investigated by X-ray
crystallography. The title compound, C24H26N2O2S crystallizes in the monoclinic crystal class in the space group P21/c with cell parameters a = 13.5800(10) ?, b = 8.9630(7) ?, c = 18.9040(10) ?, β = 106.851(3)°, Z = 4 and V = 2202.1(3) ?3. The structure has been solved by direct methods and refined to R
1 = 0.0468 for 3174 observed reflections I > 2σ(I). The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is a distorted
tetrahedron.
Graphical Abstract The title compound 1-benzhydryl-4-(toluene-4-sulfonyl)-piperazine was synthesized and the structure was investigated by X-ray
crystallography. The title compound, C24H26N2O2S crystallizes in the monoclinic crystal class in the space group P21/c with cell parameters a = 13.5800(10) ?, b = 8.9630(7) ?, c = 18.9040(10) ?, β = 106.851(3)°, Z = 4 and V = 2202.1(3) ?3. The structure has been solved by direct methods and refined to R
1 = 0.0468 for 3174 observed reflections I > 2σ(I). The structure reveals that the piperazine ring is in a chair conformation. The geometry around the S atom is a distorted
tetrahedron.
相似文献
M. A. SridharEmail: |
995.
Liying Zhu Yi Xie Xiuwen Zheng Xiang Liu Guien Zhou 《Journal of Crystal Growth》2004,260(3-4):494-499
The interesting biomimetic morphologenesis of CuS, containing urchin-like architecture and snowflake-like pattern can be separately obtained via heating different solutions. In our case, ethanol or the mixed solvent of ethanol/H2O containing CuCl2 and CS2 as raw materials in the presence of the surfactant additive cetyltrimethylammonium bromide (CTAB) have been used. The products were characterized by various techniques of XRD, SEM and ED. In the process, the solvent medium and the surfactant additive CTAB played very important roles in the formation of different biomimetic morphologies and the formation mechanisms were primarily discussed, respectively. 相似文献
996.
M. Abdi F. Zouari S. Chaabouni A. Ben Salah 《Journal of chemical crystallography》2003,33(11):839-843
The penthylenediammonium pentachlorothallate(III) salt is orthorhombic with the following unit cell dimensions: a = 7.696(3) Å, b = 13.2890(17) Å, and c = 13.503(18) Å, space group P212121 with Z = 4. The structure was solved by Patterson methods and refined to a final R value of 0.0387 for 1991 observed reflections. The structure consists of penthylenediammonium cations and polynuclear anions in which slightly distorted [TlCl6]3– octahedral sharing two vertices are interconnected into chains. These chains are themselves interconnected by means of the N–HCl bonds originating from the [NH3(CH2)5NH3]2+ entities forming a three-dimensional network. 相似文献
997.
Xiang-Jun Zheng Zhe-Ming Wang Lin-Pei Jin Chun-Hua Yan 《Journal of chemical crystallography》2002,32(12):519-523
The preparation and molecular and crystal structures of the title compound are reported. The compound crystallizes in the triclinic space group
(No. 2) with unit cell dimensions of a = 7.2493(3) Å, b = 8.9287(4) Å, c = 10.6594(4) Å, = 90.419(3)°, = 91.287(3)°, = 103.153(3)°, V = 671.62(5) Å3, and Z = 2. The molecular structure of the title compound consists of three sections, the glycine chain and the two 2,5-dioxopyrrolidin-1-ylmethyl groups. Every molecule is linked with three adjacent molecules through three hydrogen-bonding patterns which are 8-membered or 20-membered rings. The chain of rings appears periodically, which makes the molecule form a layer structure in the crystal. 相似文献
998.
5,5-Di t-butyl-2,2-biphenyldiol (I), C20H26O2, crystallizes in the orthorhombic space group P212121 with a = 18.243(2), b = 9.947(2), c = 9.685(3) Å, and Z = 4; 5,5-dimethyl-2,2-biphenyldiol (II), C14H14O2, crystallizes in the monoclinic space group P21/c with a = 9.959(2), b = 7.932(3), c = 15.392(2) Å, = 105.43(2)°, and Z = 4. The aromatic rings are tilted by 52.7(1) and 43.8(1)° to each other in compounds (I) and (II), respectively. Strong intra- and inter-molecular H-bonds connect the molecules in the crystals. 相似文献
999.
Ian R. Pottie C. V. Krishnamohan Sharma Keith Vaughan Michael J. Zaworotko 《Journal of chemical crystallography》1998,28(1):5-10
The crystal and molecular structure of 1,2-bis-{1-(2-cyanophenyl)-3-methyltriazen-3-yl-}ethane (1) and 1,2-bis-{1-(2-methoxyphenyl)-3-methyltriazen-3-yl-}ethane (2) have been determined by single crystal X-ray diffraction analysis. Bis-triazene (1) exists as the staggered conformation in the solid state, with an anti-anti configuration around the N2–N3 bond of the triazene units, whereas 2 assumes a gauche conformation with the syn-syn configuration in the triazene units. Crystal data: 1 C18H18N8, triclinic, space group P –1, a = 6.108(2), b = 8.118(3), c = 9.600(4)Å, = 101.37(7)°, = 96.47(7)°, = 102.71(5)°, V = 449.1(3)Å3, Z = 2; 2 C18H24N6O2, monoclinic, space group P 21/n, a = 13.119(5), b = 7.745(2), c = 19.201(2)Å, = 96.47(7)°, V = 1910.3(9)Å3, Z = 4. 相似文献
1000.
The structural determination by X-ray crystallography of the titled N-arylamine 4a, as well as AM1 calculations on a series of derivatives (4b–c, 5a–c), are reported. The compound 4a is monoclinic P21/c with a = 7.656(3), b = 23.655(5), c = 7.686(9) Å, = 112.59(6)°, V = 1285.2(2) Å3 and Z = 4. This structure has been used as a template for the building of some others derivatives used for AM1 calculations. The results show that the cyclization position on the aromatic rings, which can lead to two regioisomers, depends on the nature of the benzylic substituants. 相似文献