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991.
Voirrey L. Robinson 《Inorganica chimica acta》2010,363(12):2938-8867
The previously reported complex [Ru(ttpy)(CN)3]− [ttpy = 4′(p-tolyl)-2,2′:6′,2″-terpyridine] is conveniently synthesised by reaction of ttpy with Ru(dmso)4Cl2 to give [Ru(ttpy)(dmso)Cl2], which reacts in turn with KCN in aqueous ethanol to afford [Ru(ttpy)(CN)3]− which was isolated and crystallographically characterised as both its (PPN)+ and K+ salts. The K+ salt contains clusters containing three complex anions and three K+ cations connected by end-on and side-on cyanide ligation to the K+ ions. The solution speciation behaviour of [Ru(ttpy)(CN)3]− was investigated with both Zn2+ and K+ salts in MeCN, a solvent sufficiently non-competitive to allow the added metal cations to associate with the complex anion via the externally-directed cyanide lone pairs. UV-Vis spectroscopic titration of (PPN)[Ru(ttpy)(CN)3] with Zn(ClO4)2 showed a blue shift of 2900 cm−1 in the 1MLCT absorption manifold due to the ‘metallochromism’ effect; a series of distinct binding events could be discerned corresponding to formation of 4:1, 1:1 and then 1:3 anion:cation adducts, all with high formation constants, as the titration proceeded. In contrast titration of (PPN)[Ru(ttpy)(CN)3] with the more weakly Lewis-acidic KPF6 resulted in a much smaller blue-shift of the 1MLCT absorptions, and the titration data corresponded to formation of 1:1 and then 2:1 cation:anion adducts with weaker stepwise association constants of the order of 104 and then 103 M−1. Although association of [Ru(ttpy)(CN)3]− resulted in a blue-shift of the 1MLCT absorptions, the luminescence was steadily quenched, as raising the 3MLCT level makes radiationless decay via a low-lying 3MC state possible. 相似文献
992.
993.
Benjamin G. Harvey 《Inorganica chimica acta》2010,363(1):221-224
Refluxing WCl4(PMe3)3 under a nitrogen atmosphere in the presence of two equivalents of sodium amalgam leads to a reduction to the W(II) complex [cis,mer-WCl2(PMe3)3]2N2 (1), which can be converted to [mer,trans-WCl3(PMe3)2]2N2 (2) via appropriate oxidation/chlorination. Structural data have been obtained for both complexes, and demonstrate significantly increased steric crowding in 1 due to PMe3/PMe3 interactions. The N-N bond distances in the two compounds are similar, at 1.279(4) and 1.243(18) Å, respectively. 相似文献
994.
Damijana Urankar 《Inorganica chimica acta》2010,363(14):3817-5866
An alternative, mild and highly efficient synthetic approach to platinum complexes with bioactive carrier ligands features a platinum-complex-tolerant copper(I)-catalyzed 1,3-dipolar cycloaddition. As demonstrated by the preparation of novel diazenecarboxamide-carboplatin conjugates, this approach is superior to other methodologies. 相似文献
995.
A new pyridyl-carboxylate ligand, the anion of trans-4-cotininecarboxylic acid, HL, 1, has been used to prepare a new polymeric copper(II) complex, [CuLN3]2n, 2, based on a [CuLN3]2 dimeric building block. The single crystal structures of both 1 and 2 have been determined and 1 has been found to be in its zwitterionic configuration. The structure of 2 is a one-dimensional tape-like polymeric structure based on an end-on azido-bridged binuclear [Cu2N3]2 backbone moiety. Magnetic studies reveal that 2 is close to paramagnetic from 2 to 300 K with a Curie constant of 1.094 emu K/mol, a Weiss temperature of 0.73 K and a corresponding μeff of 2.09 μB. A fit of χMT for 2 with S1 = S2 = ½, yields g = 2.441(6), J = −0.49(3) cm−1, zJ = −0.38(2) cm−1 and N(α) = 0.00053(12) emu/mol, a fit that indicates the presence of both very weak intramolecular intrachain antiferromagnetic exchange coupling within the one-dimensional tape-like chains and very weak interchain antiferromagnetic exchange coupling between these chains. 相似文献
996.
Three new coordination complexes [Mn(L)(H2O)2](1,4-BDC)·2H2O (1), [Mn(L)0.5(1,4-BDC)]CH3OH·H2O (2) and [Mn(L)(H2O)2](1,2-HBDC)2·2H2O (3) were synthesized by solvothermal reactions of 1,2,4,5-tetrakis(imidazol-1-ylmethyl)benzene (L) and 1,4-benzenedicarboxylic acid (1,4-H2BDC) or 1,2-benzenedicarboxylic acid (1,2-H2BDC) with Mn(II) salt, and characterized by single crystal X-ray diffraction, IR, thermogravimetric and elemental analyses. In complexes 1 and 3, each ligand L links four Mn(II) atoms to form two-dimensional (2D) cationic network with non-coordinated 1,4-BDC2− and 1,2-HBDC− anions lying in the voids between the two adjacent layers, respectively. The 2D layers are further connected together by hydrogen bonds to give three-dimensional (3D) supramolecular structures. However, the 1,4-BDC2− in 2 acts not only as counteranion, but also as bridging ligand leading to the formation of 2-fold interpenetrated 3D framework with pcu (primitive cubic unit) topology. The Mn(II) atoms bridged by carboxylate groups in 2 show antiferromagnetic interactions. 相似文献
997.
Soma Mukherjee Chandrama Basu Asoke P. Chattopadhyay Utpal Ghosh 《Inorganica chimica acta》2010,363(12):2752-139
A blue luminescent dichlorido-bridged dinuclear copper(II) (S = 1/2) complex, [CuII2(HL)2(μ-Cl)2]·2H2O, 1a was synthesized with the 1:1 reaction of the acyclic tridentate salicylaldehyde 2-pyridyl hydrazone ligand, HL, 1. The complex 1a displays multiple bands in the visible region (400-470 nm). The association constant (Kass, UV-Vis) was found to be 1.186 × 104 for 1a at 298 K. The copper(II)-copper(III) oxidation potential lies near 0.32 V versus Ag/AgCl electrode. On excitation at 390 nm, the ligand 1 strongly emits at 444 nm due to an intraligand 1(π-π∗) transition. Upon complexation with copper(II) the emission peak is slightly red shifted (λex 390 nm, λem 450 nm, F/F0 0.81) with little quenching. Molecular structure of 1a (Cu···Cu 3.523 Å) has been determined by single crystal X-ray diffraction studies. DFT and TDDFT calculations strongly support the spectral behavior of the ligand and the complex. The complex 1a exhibits a strong interaction towards DNA as revealed from the Kb (intrinsic binding constant) 2.05 × 104 M−1 and Ksv (Stern-Volmer quenching constant) 2.47 values. The complex exhibits cytotoxic effect and the LD50 value for HeLa cells was calculated as 5.44 μM at which the cell cycle was arrested at G2/M phase. 相似文献
998.
Two new mononuclear mixed-ligand ruthenium(II) complexes with acetylacetonate ion (2,4-pentanedionate, acac) and functionalized bipyridine (bpy) in position 4, [Ru(bpyBr)2(acac)](PF6) (2; bpyBr = 4-Bromo-2,2′-bipyridine, acac = 2,4-pentanedionate ion) and [Ru(bpyOH)2(acac)](PF6) (3; bpyOH = 4-[2-methyl-3-butyn-2-ol]-2,2′-bipyridine) were prepared as candidates for building blocks. The 1H NMR, 13C NMR, UV-Vis, electrochemistry and FAB mass spectral data of these complexes are presented. 相似文献
999.
Two new manganese(II) complexes, [Mn(L1)(L1H)(ClO4)(H2O)][ClO4]2·0.5CH3CN·H2O (1) [L1 = trans-(±)2-(2,5-di(pyridin-2-yl)-4,5-dihydro-1H-imidazol-4-yl)pyridine)] and [Mn2(μ-L2)2(H2O)3(CH3CN)3][ClO4]4·2CH3CN (2) [L2 = cis-(±)2-(2,5-di(pyridin-2-yl)-4,5-dihydro-1H-imidazol-4-yl)pyridine)], have been prepared and examined by single-crystal X-ray diffraction analysis, showing that complex 1 is a mononuclear compound, whereas complex 2 is a dinuclear species. The cis/trans isomers L1 and L2 have similar coordination properties, but behave as bidentate and tridentate chelating ligands, respectively, giving distorted octahedral metal coordination geometries. X-ray diffraction studies revealed that the molecular and crystal structures are stabilized by a series of intra- and intermolecular interactions. In both cases extended supramolecular networks are generated, in compound 1 through O-H···O, O-H···N, N-H···O, N-H···N, C-H···O, C-H···N, C-H···π and π···π interactions, and in compound 2 through O-H···O, O-H···N, C-H···O and π···π interactions. The observed structural differences between the two metal complexes might be a consequence of these stabilizing effects. 相似文献
1000.
Structural determination of tetra-n-butylammonium bis(maleonitriledithiolato)platinate(1−), a polymorphic compound, revealed that one polymorph consists of a columnar arrangement of dimers of the anion and is isomorphous with a corresponding nickelate complex. In contrast to the nickelate complex, the complex exhibited no spin-Peierls transition; strong antiferromagnetic interactions were observed between the anions due to dimerization in the column. The other polymorph consists of a tetramer unit of the anion. 相似文献