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991.
992.
D. Ranchet J. B. Tommasino O. Vittori P. L. Fabre 《Journal of solution chemistry》1998,27(11):979-991
Electrochemical reduction of FeIIILCl where L is a Schiff base has been investigated in various aprotic solvents. From a plot of the half wave potential E
1/2 for the reduction of these complexes vs. E
1/2 for the oxidation of ferrocene, the solvent–solute interactions were studied: the E
1/2 variation is found to be a function of Lewis-type acceptor–donor interactions. The diffusion coefficients D in the different solvents were also been determined by linear sweep voltammetry. The variation of D is discussed in terms of viscosity and dielectric constant. 相似文献
993.
A. K. Sharma B. Khera N. K. Kaushik 《Monatshefte für Chemie / Chemical Monthly》1983,114(8-9):907-913
A series of (C9H7)2Zr(SB)Cl complexes whereSB
– is the anion of bidentateSchiff base derived from salicylaldehyde and 4-substituted anilines, viz. salicylidene-4-ansidine, salicylidene-4-phenetidine, salicylidene-4-chloroaniline, salicylidene-4-bromoaniline, salicylidene-4-iodoaniline and salicylidene-4-nitroaniline, have been synthesized by the reaction of bis(indenyl)zirconium(IV) dichloride andSchiff base (SBH) in 1:1 molar ratio in refluxingTHF in the presence of triethylamine. The new derivatives have been characterized on the basis of their elemental analyses, conductance measurements and spectral (IR,1H-NMR, UV-VIS) studies.
Bis(indenyl)zirkonium(IV)-Komplexe monofunktioneller zweizähniger Salicylidimine
Zusammenfassung Es wurde eine Reihe von (C9H7)2Zr(SB)Cl-Komplexen synthetisiert, wobeiSB – für das Anion einer zweizähnigenSchiff-Base steht. DieSchiff-Basen sind von Salicylaldehyd und 4-substituierten Anilinen hergeleitet: Salicyliden-4-anisidin,-4-phenetidin, -4-Cl-, -4-Br-, -4-I-anilin und -4-Nitroanilin. Die Synthese erfolgte über die Reaktion von Bis(indenyl)zirkonium(IV)-dichlorid mit derSchiff-Base (SBH) in einem molaren Verhältnis von 1:1 am Rückfluß in Gegenwart von Triethylamin undTHF als Lösungsmittel. Zur Charakterisierung der neuen Derivate wurden Elementaranalysen, Leitfähigkeitsmessungen und spektroskopische Daten (IR,1H-NMR, UV-VIS) herangezogen.相似文献
994.
Based on the consistency of the in vivo and in vitro interactions of drugs with DNA, a fluorimetric method has been developed as a new in vitro method for preliminary screening of antitumour agents. This method was tested using Schiff bases synthesized from salicylaldehyde with 1-alanine, 1-asparagine and 1-histidine, and complexes of these Schiff bases with Cu(Ⅱ), Zn(Ⅱ), Ni(Ⅱ) and Sn(Ⅳ) as potential antitumour agents.The study of the interaction of the complexes with DNA by a fluorescence probe ethidium bromide (EthBr)-DNA system indicated the parallelism between the binding constants and antineoplastic ratios. The relationship between structure and antitumonr activity was investigated. 相似文献
995.
Reactions of bitter salt with taurine-3,5-dibromo-salicylaldehyde schiff base gave one new Complex
[Mg(Br2TSSB)(Phen)(H2O)]·H2O (Br2TSSB=Taurine 3,5-dibromo-Salicylaldehyde Schiff Base, phen=o-phenanthroline), which was characterized by elemental analysis, IR and X-ray diffraction. The chemical formula weight of the complex is 625.58. It′s crystal belongs to monoclinic system with space group
P21/c. The cell parameters are: a=1.814 2(3) nm, b=0.814 75(14) nm, c=1.641 7(3) nm, β=90.571(4)°, and Z=4, V=2.426 4(7)
nm3, Dc=1.712 g·cm-3, F(000)=1 248, μ=3.496 mm-1. The complexes form a 3D net structure in which they are connected with hydrogen bonds and π-π stacking. The Mg(II) formed a distorted coordination tetragonal pyramid. CCDC: 286194. 相似文献
996.
Deoxyadenosine and deoxycytidine have nucleophilic amino groups so that the undesired N-phosphitylation of these amino groups occurred in the previous phosphoramidite methods without base protection. We report that the N-phosphitylation could be considerably suppressed in our new HOBt-mediated coupling strategy via phosphite intermediates as reactive species. Thus, 99.7-99.9% O-selective internucleotidic bond formation was achieved. 相似文献
997.
Poly(4-vinyl pyridine) is used as a polymeric ligand to react with metal alkyls, MenM (n = 3, M = Al, Ga or In; n = 2, M = Cd or Zn) to form adducts. The adducts are characterized by solid state 13C NMR, infrared spectroscopy, microanalyses and differential scanning calorimetry (DSC). All the adducts are nonpyrophoric and thermally dissociable, so they may have potential both for use in adduct purification processes or for use as safer metal alkyl sources for Metal–Organic Chemical Vapor Deposition. 相似文献
998.
The fluorescence spectra of N--salicylidene-p-(N,N--dimethylamino)aniline have beeninvestigated in various solvents. Three kinds of fluorescence have been found in the solutionsof various concentrations. They are the excited intermediate (EI) which is formed when theproton transfer has occurred but essentially retains the geometry of the enol tautomer, theexciplex (EX) which consists of a ground monomer and an excited state intermediate and theexcited dimer (ED) which is caused by ground state aggregate. The fluorescence lifetimesof the fluorophores have been measured in tetrahydrofuran (THF). Luminescent mechanismhas been discussed based on the fluorescence spectra and the kinetic data of the compound. 相似文献
999.
M. Montazerozohori S.A. Musavi A. Masoudi-asl H. Mohammadi R. Naghiha A. Assoud 《Arabian Journal of Chemistry》2019,12(7):1463-1473
Three new four coordinated zinc(II) complexes have been synthesized and characterized by IR, UV, elemental analysis, 1H and 13C NMR and X-ray single crystal analysis. The elemental analyses of the complexes are in agreement with the general formula of ZnLX2 wherein L = Schiff base ligand and X = Cl?, Br? and I?. Low molar conductivities in DMF indicated non-electrolyte character of all complexes. Spectroscopic studies well confirmed the coordination via azomethine nitrogens of the ligand to zinc ion. The single crystal X-ray analysis shows that ZnLBr2 crystallizes in the triclinic crystal system with space group . It contains two crystallographically independent molecules noted as A and B, with both Zn1A and Zn1B being almost in perfect tetrahedral environments (τ4 = 0.94 for Zn1A and τ4 = 0.93 for Zn1B). A detailed structural analysis shows that there are three non-classical hydrogen bondings of C–H…Br in the structure. Various C–H…π and C–H…Br interactions play an important role in stabilizing the molecular structure and then give rise to a 3D supramolecular structure of the ZnLBr2 complex. After characterization, the Schiff base and its complexes were screened in vitro for their antibacterial and antifungal activities by disk diffusion technique. Also the ability of the complexes for DNA cleavage was studied by agarose gel electrophoresis method. Finally, thermal behavior of the complexes has been studied by thermo-gravimetry and then some activation kinetics parameters of decomposition steps were evaluated based on TG/DTG plots. 相似文献
1000.
《Tetrahedron letters》2003,44(34):6375-6378
A convenient and efficient synthesis of 3,5-di(trimethylsilylethynyl)phenylacetylene and p-[3,5-di(trimethylsilylethynyl)-1-phenylethynyl]phenylacetylene and the naphthylethynyl homologues terminal acetylenes of 5-(N,N-dimethylamino)naphthylethyne have been carried out. These terminal acetylene compounds serve to prepare nanometer-sized conjugated 1,3,5-tri(ethynylphenyl)benzene and 1,3,5-tri(ethynylnaphthyl)benzene oligomers, by means of heterocoupling with 1,3,5-triiodobenzene, catalysed by palladium, in excellent yields. Both the ethynylphenyl or ethynylnaphthyl homologues chains show fluorescence emission radiation, with important quantum yield. 相似文献