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991.
《Journal of Coordination Chemistry》2012,65(6):711-716
The synthesis of the binuclear complex [(tren)Cu(4,4'-bipy)Cu(tren)] (ClO4)4 where tren = tris(2-aminoethyl) amine and 4,4'-bipy = 4,4'-bipyridine, is described. Single-crystal X-ray diffraction study of the homobinuclear complex shows that two copper(II) ions are bridged by 4,4'-bipyridine and each copper(II) ion is trigonal-bipyramidally coordinated, with tren occupying four sites [Cu-N = 2.030(2), 2.047(2), 2.078(2), and 2.119(2) Å respectively] and a bridging 4,4'-bipyridine in the apical position. The Cu-Cu distance is 11.11 Å. In variable-temperature ESR spectra, the presence of hyperfine structure suggest that some interaction exists between the two copper(II) ions. Temperature-dependent susceptibility studies indicate that it is a weak ferromagnetic interaction with 2J = 1.23 cm-1. 相似文献
992.
《Journal of Coordination Chemistry》2012,65(14):1485-1491
A copper(II) complex of a sulfonate derivative of chrysin, 5,7-bihydroxyflavone-6-sulfonate, Cu(C15H8O7S)(3H2O), has been prepared. The complex was characterized by elemental analysis, spectroscopic measurements and single-crystal X-ray diffraction studies. It crystallizes in the monoclinic space group C2/c, with a?=?16.036(18), b?=?6.944(8), c?=?28.03(3)?Å, β?=?94.463(17)°, V?=?3112(6)?Å3, Z?=?8. In the complex, Cu(II) is five-coordinate and all donors are oxygen atoms. Hydrogen bonds and π–π stacking interactions in the crystal lead to the formation of a three-dimensional supramolecular motif. 相似文献
993.
《Journal of Coordination Chemistry》2012,65(5):373-381
The crystal structure of the rigid bidentate nitrogen ligand bis[N-(2,6-diisopropylphenyl)imino]acenaphtene (o, o'-iPr2C6H3-BIAN) is described. Syntheses, electronic spectra and electrochemical properties of two copper complexes containing (o,o'-iPr2C6H3-BIAN), namely, [CuCl(o,o'-iPr2C6H3-BIAN)2]Cl (1) and [Cu(o,o'-iPr2C6H3-BIAN)2](CIO4)(AcOH)2 (2), where AcOH=acetic acid, are reported. Although in both complexes two o,o'-iPr2C6H3-BIAN ligands are coordinated, geometries about the copper atom are significantly different. While complex 2 displays a strongly "flattened" distortion towards square-planar geometry, in complex 1 square-pyramidal coordination with an almost perfect planar arrangement of two o,o'-iPr2C6H3-BIAN ligands around the copper centre is suggested. 相似文献
994.
《Journal of Coordination Chemistry》2012,65(12):1269-1277
A five-coordinate copper complex with the tripod ligand tris(1H-benzimidazol-2-ylmethyl)amine (ntb), of composition [Cu(ntb)(H2O)] (C1O4)2?·?C5H4N2O3?·?H2O (C5H4N2O3?=?4-nitropyridine-N-oxide), was synthesized and characterized by means of elemental analyses, electrical conductivities, thermal analyses, IR, and U.V. The crystal structure of the copper complex has been determined by single-crystal X-ray diffraction, and shows that the CuII is bonded to a tris(1H-benzimidazol-2-ylmethyl)amine (ntb) ligand and a water molecule through four N atoms and one O atom, giving a distorted trigonal–bipyramidal coordination geometry with approximate C 3 molecular symmetry. Cyclic voltammograms of the copper complex indicate a quasi-reversible Cu+2/Cu+ couple. Electron spin resonance data confirm a trigonal-bipyramidal structure and with g 2?<?g ζ and a very small value of A 2 (20?×?10?4?cm?1). 相似文献
995.
996.
《Journal of Coordination Chemistry》2012,65(11):1817-1826
The reaction of [Cu(CH3CN)4]BF4, pyridine-2-carbaldehyde azine, triphenylphosphine, and diimine ligands derived from 4,4′-bipyridine and/or trans-1,2-bis(4-pyridyl)ethylene gave two copper(I) coordination polymers, [Cu2(µ-paa)(µ-bp)(PPh3)2] n (BF4)2 n (1) and [Cu2(µ-paa)(µ-tbpe)(PPh3)2] n (BF4)2 n (2). Despite 1 and 2 differing only by a double bond, they have significantly different photophysical and structural properties. Crystallographic studies show that 2 is a porous solid while 1 is not porous. The two polymers are photoluminescent as solids at room temperature, but the emission peaks of 2 are obviously red-shift. Moreover, different from 1, 2 has a good emission centered at 510 nm in CH3CN solution. The double bond in the diimine ligand plays an important role in these two copper(I) coordination polymers. 相似文献
997.
《Journal of Coordination Chemistry》2012,65(10):1663-1670
The reaction of 1,1-diethyl-3-(4-fluorobenzoyl)-thiourea (HL) with CuCl2 ·?2H2O and NiCl2 ·?6H2O give two complexes, Cu(HL)3Cl (1) and NiL2 (2). The crystal structures of these products were determined by single crystal X-ray diffraction. In 1, three HL molecules are unidentate, coordinating through the sulfur, and the copper is tetrahedral with three S and one Cl. In 2, two HL molecules are O and S donor bidentate and coordinate as anionic species with loss of the proton from the acyl-substituted nitrogen; the nickel is square-planar. 相似文献
998.
《Journal of Coordination Chemistry》2012,65(5):453-460
Two malonato-bridged hexamethylenetetramine coordination polymers, M2(hmt)(H2O)2(mal)2 [hmt?=?hexamethylenetetramine, mal?=?malonate(2-), M?=?Mn (1), Cu (2)] were prepared and structurally characterized. The isostructural complexes are orthorhombic, space group Imm2, with a?=?7.104(1), b?=?15.982(3), c?=?7.702(1)?Å, Z?=?2, D calc?=?1.862?g?cm?3(1) and a?=?6.962(3), b?=?15.500(7), c?=?7.627(3)?Å, Z?=?2, D calc?=?2.047?g?cm?3for 2. The transition metals are octahedrally coordinated by one nitrogen atom of an hmt ligand and five oxygen atoms of a water molecule and three malonate anions. The latter coordinate in chelating/bis-monodentate mode to give 2D layers with a (4,?4) topology, and which are pillared by bridging bidentate hmt ligands to generate an open 3D framework with channels extending in the [001] direction. Over the temperature range 5–300?K, 2 behaves paramagnetically, following the Curie–Weiss law χm(T???θ)?=?4.521(6)?cm3mol?1K with a Weiss constant θ?=??4.8(2)?K. 相似文献
999.
《Journal of Coordination Chemistry》2012,65(10):857-862
A new kind of copper(II) complex, CuL(MeOH) (H2L?=?(E)-N 1-(2-((2-aminocyclohexydiimino)(phenyl)methyl)-4-chlorophenyl)-N 2-(2-benzyl-4-chlorophenyl)oxalamide) has been synthesized and its structure determined by single-crystal X-ray methods. Copper(II) ion is five-coordinate, bonding to four nitrogen atoms from H2L and one oxygen atom from MeOH. Hydrogen bonds in the crystal result in the formation of a one-dimensional structure. EPR spectra are discussed. Computer simulation gave g||?=?2.200, g⊥?=?2.002. On the basis of the synthesis and the crystal structure, the mechanism of the metal template reaction involved in the formation of the complex was verified. 相似文献
1000.
《Journal of Coordination Chemistry》2012,65(8):1375-1384
Mn(2,2′-bpy)2(HFGA) (1) and [Cu4(μ3-OH)2(μ2-OH)2(H2O)2(2,2′-bpy)4]?·?2HFGA?·?4H2O (2) (H2HFGA?=?hexafluoroglutaric acid and 2,2′-bpy?=?2,2′-bipyridine) have been synthesized and characterized by X-ray structural analyses. 1 is a monomer with six-coordinate Mn2+ from two oxygens of HFGA and four nitrogens of two 2,2′-bpy. Complex 2 is tetranuclear with four Cu2+ ions bridged by triple-bridging μ3-OH and double-bridging μ2-OH. There are two crystallographically independent Cu2+ ions in different five-coordinate environments. Cu1 is coordinated by 2,2′-bpy and three OH ligands. Cu2 is coordinated by 2,2′-bpy, two μ3-OH ligands, and one water molecule. The mononuclear and tetranuclear molecules as building blocks are connected to construct different 3-D supramolecular architectures via noncovalent interactions. Particularly, the lone pair (lp)–π (F···π) interaction in 1 is observed. A hybrid water-anionic tape by linkage of {[(H2O)4(HFGA)]2 4?} n fragments consisting of water dimers and HFGA anions in 2 is observed. 相似文献