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991.
Miguel Clemente-León Eugenio Coronado Carlos J. Gómez-García Samuel Constant Jérôme Lacour 《Inorganica chimica acta》2007,360(3):955-960
The synthesis, structure and physical properties of two new radical salts formed with the organic donor bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF or ET) and a racemic mixture of the chiral anion (tris(tetrachlorobenzenediolato)phosphate(V)) (TRISPHAT) are reported. The structure of the salts (ET)4[TRISPHAT]4 · 3.5H2O (1) and (ET)(TRISPHAT) · CH2Cl2 · CH3CN (2) has been solved by X-ray single crystal diffraction. Unusual packings of ET molecules are obtained in the two structures. The electrical properties indicate that both compounds are insulators. This is in agreement with the isolation of the ET molecules and their complete ionization. On the other hand, the anisotropy of the ESR lines has been studied by Q-band ESR spectra. 相似文献
992.
Two Cu(II)-containing complexes, [Cu(pbbt)Cl2]2 · CH3OH (1) and [Cu(bbbt)1.5Cl2]n (2) (pbbt = 1,1′-(1,3-propylene)bis-1H-benzotriazole, bbbt = 1,1′-(1,4-butanediyl)bis-1H-benzotriazole), have been synthesized and characterized. Single crystal X-ray diffraction shows that 1 exhibits discrete binuclear structure, in which two Cu(II) ions are bridged together through two Cl− anions and two pbbt ligands. Whereas 2 displays infinitely extended two-dimensional reticulate grid structure with hexagon units in which six Cu(II) ions act as corners and six bbbt ligands serve as sides. The electrochemical studies show that their redox processes in the potential range of 0.1-0.9 V are quasi-reversible and controlled by diffusion. The diffusion coefficients decrease with increase in the molecular weight of the complexes and the size of the molecules. Further investigation exhibits that their electrochemical properties obtained from experiments are consistent with their crystal data and the computed parameters. For example, the observed one-pair well-defined redox waves in the cyclic voltammetry (CV) diagrams correspond to the X-ray diffraction results that all of the Cu(II) ions in the title complexes are equivalent, respectively; the cathodic shifts (as compared with CuCl2) of the reduction potentials of 1 and 2 are in agreement with the computed results: the LUMO energies of the complexes (−3.789 eV for 1 and −4.330 eV for 2) are higher than that of CuCl2 (−6.942 eV). 相似文献
993.
Alma Itzel Olivos-Surez Gustavo Ríos-Moreno Simn Hernndez-Ortega Rubn A. Toscano Juventino J. García David Morales-Morales 《Inorganica chimica acta》2007,360(15):4133-4141
The fluorinated thioether compounds [C6H4Br-2-(CH2SRF)] (SRF = SC6F5 (1), SC6F4-4-H (2), SC6H4-2-F (3), SC6H4-3-F (4), SC6H4-4-F (5)) were synthesized and the reactivity of (1) was explored with transition metal complexes of the group 10. The results obtained indicate that the reactivity of these ligands is strongly dependent on the oxidation state of the metal center on the complex. Thus, products of the coordination of Pd(II) and Pt(II) to the sulfur moiety were obtained and unequivocally characterized by single crystal X-ray diffraction analyses. While spectroscopic evidence indicates that reaction of the Pt(0) compound [Pt(PEt3)3] leads to the formation of C–Br activation products, it is worth noting that similar reactions with Ni(0) and Pd(0) compounds only afford complex mixtures that in most of the cases indicate desulfurization of the ligands and decomposition of the metallic starting materials. 相似文献
994.
Adrian E. Ion 《Inorganica chimica acta》2007,360(13):3925-3931
The synthesis of two nickel(II) complexes based on a central bridging triaminoguanidine scaffold and a capping ligand per metal ion is reported. When 2,2′-bipyridine (bipy) is utilized as co-ligand the complex [Ni3LBr(bipy)3(H2O)3]NO3 · 9H2O · 1.5DMF (1) is obtained which crystallizes in the hexagonal space group P63/m. Complex 1 shows an interesting supramolecular structure pattern with alternating hydrophilic and hydrophobic layers characterized by extensive hydrogen-bonding and π-π-stacking, respectively. With 2,4,6-(2-pyridyl)-1,3,5-triazine (tptz) as capping ligand, complex [Ni3LBr(tptz)3]ClO4 · 7H2O · 1.5DMF (2) is obtained. The magnetic susceptibility data can be fitted using an equilateral triangle model () with an isotropic coupling constant of J=-31.0±0.6 for 1 and for 2. 相似文献
995.
We have shown previously that 8-(5′-N,N-dimethylamino-1′-naphthalene)-sulfonamidoquinoline (DANQUIN) demonstrated a remarkable selectivity and sensitivity for the Zn(II) ion. In this work, the crystal structures of DANQUIN, Cu(DANQUIN)2 and Cu(DANPY)2 (DANPY, N-2-picolyl-(5′-N,N-dimethylamino-1′-naphthalene)-sulfonamide) are reported and compared with the simulated structure of Zn(DANQUIN)2, which is important for the understanding of the factors that govern the fluorescence of DANQUIN. Free DANQUIN mainly displays the fluorescence of the dansyl group at 547 nm while the Zn(II)-DANQUIN complex mainly shows the enhanced fluorescence of aminoquinoline at 469 nm, while the emission of the dansyl group shifted to 517 nm with an almost constant intensity. This result demonstrates the advantage of this hybrid fluorescent chemosensor for Zn(II), and also makes it a potential candidate for ratiometric Zn(II) detection. 相似文献
996.
The preparation and crystal structure of a decametallic MnII carboxylate cluster containing neutral 2-pyridinealdoxime, (py)C(H)NOH, and its anion, (py)C(H)NO−, is reported. The reaction between Mn(O2CPh)2 · 2H2O and (py)C(H)NOH in CH2Cl2, in the presence of NH4PF6, produces the complex [Mn10(O2CPh)12{(py)C(H)CNO}6{(py)C(H)NOH}2](PF6)2 · 2.6CH2Cl2 · 1.3H2O (1 · 2.6CH2Cl2 · 1.3H2O) in good yield. The cationic complex consists of ten MnII ions assembled together by four η1:η1:η3:μ4 and two η1:η1:η2:μ3 oximato(−1) ligands, and four η1:η2:μ3 ligands to form an unprecedented core, where R = PhCO and R′ = (py)C(H)N. Peripheral ligation is provided by a combination of bridging benzoates and chelating (py)C(H)NOH ligands. Dc magnetic susceptibility studies reveal the presence of dominant antiferromagnetic interactions leading to a spin ground-state of ST = 0. A survey of the ternary reaction system is attempted with comparisons to previously reported complexes. 相似文献
997.
Hydrazone Schiff base-manganese(II) complexes: Synthesis, crystal structure and catalytic reactivity
Five dissymmetric tridentate Schiff base ligands, containing a mixed donor set of ONN and ONO were prepared by the reaction of benzhydrazide with the appropriate salicylaldehyde and pyridine-2-carbaldehyde and characterized by FT-IR, 1H and 13C NMR. The complexes of these ligands were synthesized by treating an ethanolic solution of the appropriate ligand and one equivalent Et3N with an equimolar amount of MnCl2 · 4H2O or alternatively by a more direct route in which an ethanolic solution of benzhydrazide was added to ethanolic solution of appropriate salicylaldehyde and MnCl2 · 4H2O solution to yield [MnCl(L1)(H2O)2], [Mn(L2)2(H2O)2], [MnCl(L3)], [MnCl(L4)] and [MnCl2(H2O)(L5)]. The hydrazone Schiff base ligands and their manganese complexes including HL1-4 and L5 (HL1 = benzoic acid (2-hydroxy-3-methoxy-benzylidene)-hydrazide, HL2 = benzoic acid (2,3-dihydroxy-benzylidene)-hydrazide, HL3 = benzoic acid (2-hydroxy-benzylidene)-hydrazide, HL4 = benzoic acid (5-bromo-2-hydroxy-benzylidene)-hydrazide, L5 = benzoic acid pyridine-2-yl methylene-hydrazide) were characterized on the basis of their FT-IR, 1H and 13C NMR, and molar conductivity. The crystal structures of HL1 and [MnCl2(H2O)L5] have been determined. The results suggest that the Schiff bases HL1, HL2, HL3, and HL4 coordinate as univalent anions with their tridentate O,N,O donors derived from the carbonyl and phenolic oxygen and azomethine nitrogen. L5 is a neutral tridentate Schiff base with N,N,O donors. ESI-MS for the complexes Mn-L2,3,5 provided evidence for the presence of multinuclear complexes in solution. Catalytic ability of Mn-L1-5 complexes were examined and found that highly selective epoxidation (>95%) of cyclohexene was performed by iodosylbenzene in the presence of these complexes and imidazole in acetonitrile. 相似文献
998.
Holger Braunschweig Guy K.B. Clentsmith Steffen Hess Thomas Kupfer Krzysztof Radacki 《Inorganica chimica acta》2007,360(4):1274-1277
The aluminum-bound ferrocene complex, [Fe(η5-C5H4)2]2Al3Me5 (4), has been isolated and structurally characterized. 4 derives from metathesis between dilithiated ferrocene and AlMe2Cl. The stoichiometry of the reaction is satisfied by elimination of AlMe3 as its tetramethylenediamine (TMEDA) adduct. 相似文献
999.
Reaction of platinum(II) salts with 5-ferrocenylpyrimidine (FcPM) afforded cis-[Pt(NH3)2(FcPM)2](PF6)2 (1), trans-[Pt(NH3)2(FcPM)2](PF6)2 (2), cis-[PtCl2(FcPM)2] (3), and cis-[PtCl2(DMSO)(FcPM)] (4): their spectroscopic and electrochemical properties were investigated. Complexes 1 and 2 were structurally characterized by X-ray crystallography. 相似文献
1000.
A 14-membered tetraaza macrocycle, 2,13-bis(2-carbomethoxyethyl)-5,16-dimethyl-2,6,13,17-tetraazatricyclo[16.4.0.1.1807.12]docosane (L2) bearing two N-CH2CH2COOMe groups, and its nickel(II) and copper(II) complexes have been prepared and characterized. The nickel(II) and copper(II) complexes of 2-(2-carbomethoxyethyl)-5,16-dimethyl-2,6,13,17-tetraazatricyclo[16.4.0.1.1807.12]docosane (L3) containing one N-CH2CH2COOMe group have also been prepared. The crystal structure of [NiL2](ClO4)2 shows that the complex has a slightly distorted trans-octahedral coordination geometry with two relatively short axial Ni-O (N-CH2CH2COOMe group) bonds (2.136(3) Å). In various solvents, however, a considerable proportion of [NiL2]2+ exists as a square-planar form, in which the functional pendant arms are not involved in coordination. The proportion of the square-planar isomer varies with solvents in the order of nitromethane ? acetonitrile < H2O < DMF ? DMSO. In the case of [CuL2](ClO4)2, only one N-CH2CH2COOMe group is involved in coordination. The N-CH2CH2COOMe group of [NiL3](ClO4)2 is not directly involved in coordination even in the solid state, though the functional group of [CuL3](ClO4)2 is coordinated to the metal ion. 相似文献