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41.
From a range of preparative methods, three geometric isomers of bis(diphenylarsino)methane‐dichloroplatinum(II) have been isolated, viz. cis‐PtCl2(dpam), trans, trans‐Pt2Cl4(dpam)2 and cis, trans‐Pt2Cl4(dpam)2. Their structures were determined by single‐crystal X‐ray diffraction. 相似文献
42.
Gerd Eyring Thomas Schönherr Hans -Herbert Schmidtke 《Theoretical chemistry accounts》1983,64(2):83-96
The 90 K diffuse reflectance spectra of some octahedral Rh(III), Ir(III) and Pt(IV) complex compounds with chloride, thiocyanate and amine ligands are reported. The spectra show in the visible and near ultraviolet distinct bands due to spin-orbit components of singlet-triplet d-d transitions which are explained by ligand field calculations including spin-orbit coupling considering all possible d-electron configurations. Model parameter sets are obtained by fitting the measured band peaks to possible transitions between calculated energy levels. For some of the bands the vibrational structure could be resolved which is assigned to metal-ligand stretching vibrations of the electronically excited complex octahedra with vibrational fundamentals lower than those of the ground state. 相似文献
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45.
Colorless single crystals of Cd[AlCl4]2 grow from the melt of CdCl2 and AlCl3 upon slow cooling from 250°C. The crystal structure [monoclinic, P1a1, Z = 2, a = 1288.7(2), b = 660.2(1), c = 705.1(1) pm, β = 92.89(1)º] may be derived from hexagonally closest packed layers of Cl?. Octahedral and tetrahedral holes are filled with Cd2+ and Al3+ in a 1:2 ratio between all layers stacked in the [104] direction. Cd[GaCl4]2 and Cd[AlBr4]2 are isotypic. Reduction of Cd[AlCl4]2 with excess cadmium shot and slow cooling from 350°C yields plate-like very moisture-sensitive, colorless single crystals of Cd2[AlCl4]2. The crystal structure [triclinic, C1 , Z = 2, a = 655.47(3), b = 1135.26(1), c = 935.23(6) pm, α = 89.70(2)º, β = 103.61(1)º, γ = 90.455(1)º] is built from slabs stacked in the [100] direction consisting of ethane-like [Cd2Cl6] units with a Cd? Cd distance of 256.1 pm sharing common vertices with [AlCl4] tetrahedra. 相似文献
46.
Cs3[Tb10(C2)2]Cl21, A New Formula and Structure Type with Isolated Dimeric Clusters Cs3[Tb10(C2)2]Cl21 is obtained via the metallothermic reduction of TbCl3 with caesium in the presence of graphite as black single crystals. The crystal structure (monoclinic, C2/c, Z = 4; a = 2318.72(13); b = 1245.8(9); c = 1502.0(13) pm; β = 98.13(6)°; R = 0.089; Rw = 0.049) contains dimeric clusters that are built from two octahedra connected via one common edge and filled with C2 units. These isolated [Tb10(C2)2] clusters are surrounded by 26 chloride ligands which are then connected via i—a and a—a bridges in a way that voids for Cs+ of coordination number 10 are formed. 相似文献
47.
Caesium heptaiodo‐dititanate(III), CsTi2I7, is obtained from CsI, Ti and TiI4 at 250 °C in a sealed tantalum ampoule as dark red single crystals. The crystal structure (trigonal, R‐3, a = 1706.6(3), c = 2088.3(5) pm, Z = 12, R1 = 0.0619) contains [TiI4] tetrahedra sharing common vertices (with Ti—I—Ti angles of 180°) to isolated ditetrahedra [Ti2I7]—. It may also be described as a cubic closest packing of alternating CsI3 and I4 layers between which neighbouring tetrahedra are occupied in a way that [Ti2I7]— ditetrahedra are achieved. http://www.gerdmeyer.de 相似文献
48.
Gerd Meyer 《无机化学与普通化学杂志》1992,618(12):18-25
CS[Er6C]I12 and cs2Lu[Lu6C]CI18: Examples for Quaternary Reduced Halides of the Lanthanides with Isolated “Clusters” Cs[Er6C]I12 and Cs2Lu[Lu6C]Cl18 were obtained as byproducts through metallothermic reductions of ErI3 and LuCl, with cesium in the presence of carbon in sealed tantalum containers at temperatures ranging from 700 to 940 °C. Cs2Lu[Lu6C]Cl18 (isostructural with Cs2Zr[Zr6H]Cl18, R 3 , a = 981.7 pm, c = 2723.2 pm, Z = 3, R = 0.082, R, = 0.053) contains octahedral [Lu6C] clusters which are slightly compressed along the threefold axis and edge-bridged by twelve chloride anions to form [Lu6C]Cl12 units. Six additional Cl in exo positions of the cluster provide octahedral coordination for the seventh Lu3+. Cs+ occupies anticuboctahedral interstices within the Cl+ layers as a part of the (hexagonal) closest packed arrangement. Cs[Er6C]I12 (trigonal, R 3, a = 1112.0pm, c = 2063.8pm, Z = 3, R = 0.094, R, = 0.068) exhibits [Er6C]I12 units as well and shows the structural framework of Sc[Sc6N]Cl12. Instead of Sc3+ in octahedral holes, cesium occupies a regular iodide position within the ccp sheets forming [CsI3] layers. Both halides are compared with other compounds of the lanthanides containing isolated [M6X12] clusters. The extreme electron deficiency is discussed. 相似文献
49.
Ternary Halides of the A3MX6 Type. IV. Ternary Halides of Scandium with Sodium, Na3ScX6 (X = F, Cl, Br): Synthesis, Structures, Ionic Conductivity X-ray studies on single crystals of Na3ScF6 and Na3ScBr6 show, that Na3ScF6 crystallizes with the cryolite type (monoclinic, P21/n, Z = 2, a = 560.16(9), b = 580.31(8), c = 812.1(2)pm, β = 90.720(14)°) and Na3ScBr6, as the only ternary bromide of the rare earth elements with sodium, in the Na3CrCl6 type (trigonal, P3 1c, Z = 2, a = 728.95(7), c = 1309.29(17)pm). The ionic conductivity of powder samples of Na3ScF6, Na3ScBr6 and of Na3ScCl6 was studied by impedance spectroscopy. Activation energies were determined as 1.22 eV, 0.80 eV and 0.71 eV for the fluoride, chloride and bromide, respectively. The differences are explained from the crystal structures and the sizes and polarizabilities of the anions. 相似文献
50.
Two New Silicate-Chlorides with Divalent Europium: LiEu3[SiO4]Cl3 and Li7Eu8[SiO4]4Cl7 LiEu3[SiO4]Cl3 was prepared by reaction of LiCl with Eu2SiO4 and Li7Eu8[SiO4]4Cl7 from Li with Eu2O3, SiO2 and LiCl. The crystal structures of LiEu3[SiO4]Cl3 (Pmna, a = 946.95(13); b = 699.52(8); c = 1 368.0(2) pm; Z = 4; R1 = 0.0325, R2w = 0.0642) and Li7Eu8[SiO4]4Cl7 (P21/c; a = 851.85(5); b = 948.62(7); c = 1 679.0(2) pm; β = 96.221(8)°; Z = 2; R1 = 0.0352, R2w = 0.0744) were determined from four-circle diffractometer data. LiEu3[SiO4]Cl3 contains [Li(SiO4)2] units and LiCl6 octahedra while in Li7Eu8[SiO4]4Cl7 larger ?lithosilicate”? groups are found. In both structures, the Eu2+ ions are coordinated mostly eightfold by O2? and Cl? ligands. 相似文献