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211.
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The enhanced biological activities of three Zn (II) complexes based on different 1,2,4‐triazole fungicides
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Guo‐yu Ren Jie Li Xu‐zhan Wei Jin‐hua Zhou Biao Yan Zhao‐qi Guo Ying‐hui Ren Xiao‐hong Sun Hai‐xia Ma 《应用有机金属化学》2018,32(9)
In order to screen effective fungicides, three Zn (II) complexes, [Zn L 1 4 (NO3)2]·2H2O·2EtOH ( 1 ), [Zn L 2 4 (NO3)2] ( 2 ), and [Zn L 3 4 (DMF)2](NO3)2 ( 3 ), ( L 1 = paclobutrazol, L 2 = diniconazole, and L 3 = hexaconazole), were synthesized and characterized by elemental analysis, FT‐IR spectroscopy, and single‐crystal XRD. The antifungal activities of these complexes were then evaluated against four selected fungi using the mycelial growth rate method. The resulting data indicate that all the complexes show the enhanced antifungal activities than the corresponding ligand and mixtures. And, the interactions between the metal salt and ligands in the three complexes seem to be synergistic. According to the study of the influence of the structures on the activity, complex 2 with C=C linkage and 2,4‐dichlorophenyl moieties enhances the bioactivity significantly, especially against Wheat gibberellic ( II ). Density functional theory (DFT) calculations were carried out to help explain the enhanced bioactivity of the Zn (II) complexes. Meanwhile, all complexes are excellent grow‐regulators, especially complex 3 . The resulting data show that the complexes based on triazole fungicides have the potential applications in agriculture. 相似文献
214.
In this letter, a comparison between three types (two linear and one nonlinear) of models of skeletal muscle stiffness is shown. Results are compared with experimental data for biceps brachii in the case of muscle stretching and with the Hill equation for a biological muscle. It is shown that results for nonlinear stiffness model in case of length-force relationship fits to the experimental data. 相似文献
215.
Matrix-assisted laser desorption/ionization (MALDI) is a soft ionization technique which can be used in mass spectrometry to produce ions from biomolecules without inducing the fragmentation associated with traditional methods of ionization. When used with small molecules, the lack of fragmentation allows identification of specific molecules against a background of alternative signals; thus, for example, the presence of drug molecules and metabolites can be distinguished from a range of alternative biomolecules present within a tissue sample. Using highly collimated lasers in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) allows imaging of a tissue sample whereby the laser is rastered across the sample and individual mass spectra are collected in a serial manner. Thus, the distribution of the molecules within the tissue sample can be presented in the form of a 2D image. While the detection of specific drug molecules and metabolites within biological samples has its uses, quantification of those same molecules would be of greater benefit in a clinical setting. However, accurate quantification presents additional challenges. We present an overview of the MALDI-MS technique followed by recent progress in profiling drugs and their metabolites through imaging drug distributions within tissues and finish with recent developments in the quantification of drugs in tissues by MALDI-MSI. 相似文献
216.
Coordination compounds of Fe(III), Zn(II), Ni(II), Co(II), Cu(II), Cd(II) and Mn(II) ions were synthesized from the ligand [4,4′‐((((ethane‐1,2‐diylbis(oxy))bis(2,1‐phenylene))bis(methanylylidene))bis(azanylylidene))diphenol]ethane (H2L) derived from the condensation of bisaldehyde and 4‐aminophenol. Microanalysis, magnetic susceptibility, infrared, 1H NMR and mass spectroscopies, molar conductance, X ray powder diffraction and thermal analysis were used to confirm the structure of the synthesized chelates. According to the data obtained, the composition of the 1:1 metal ion–bis‐Schiff base ligand was found to be [M(H2L)(H2O)2]Cln (M = Zn(II), Ni(II), Co(II), Cu(II), Cd(II) and Mn(II), n = 2; Fe(III), n = 3). Magnetic susceptibility measurements and reflectance spectra suggested an octahedral geometry for the complexes. Central metals ions and bis‐Schiff base coordinated together via O2 and N2 donor sites which as evident from infrared spectra. The Gaussian09 program was applied to optimize the structural formula for the investigated Schiff base ligand. The energy gaps and other important theoretical parameters were calculated applying the DFT/B3LYP method. Molecular docking using AutoDock tools was utilized to explain the experimental behaviour of the Schiff base ligand towards proteins of Bacillus subtilis (5 h67), Escherichia coli (3 t88), Proteus vulgaris (5i39) and Staphylococcus aureus (3ty7) microorganisms through theoretical calculations. The docked protein receptors were investigated and the energies of hydrogen bonding were calculated. These complexes were then subjected to in vitro antibacterial studies against several organisms, both Gram negative (P. vulgaris and E. coli) and Gram positive (S. pyogones and B. subtilis). The ligand and metal complexes exhibited good microbial activity against the Gram‐positive and Gram‐negative bacteria. 相似文献
217.
《应用有机金属化学》2017,31(11)
A novel azo dye ligand, 2,2′‐(1,3‐phenylenebis(diazene‐2,1‐diyl))bis(4‐chlorophenol), was synthesized from the diazotization of m ‐phenelyenediamine and coupling with p ‐chlorophenol in alkaline medium. Mononuclear Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes of the azo ligand (H2L) were prepared and characterized using elemental analyses, infrared spectroscopy, electron spin resonance, magnetic susceptibility, conductance measurements and thermal analyses. The UV–visible, 1H NMR and mass spectra of the ligand and its chelates were also recorded. The analytical data showed that the metal‐to‐ligand ratio in the mononuclear azo complexes was 1:1. Diffuse reflectance and magnetic moment measurements revealed the complexes to have octahedral geometry. The infrared spectral data showed that the chelation behaviour of the ligand towards transition metal ions was through phenolic oxygen and azo nitrogen atoms. The electronic spectral results indicated the existence of π → π* (phenyl rings) and n → π* (─N═N) and confirmed the mentioned structure. Molar conductivity revealed the non‐electrolytic nature of all chelates. The presence of water molecules in all complexes was supported by thermal studies. Molecular docking was used to predict the binding between H2L and the receptors of breast cancer mutant 3hb5‐oxidoreductase, crystal structure of Escherichia coli (3 t88) and crystal structure of Staphylococcus aureus (3q8u). The molecular and electronic structure of H2L was optimized theoretically and the quantum chemical parameters were calculated. In addition, the effects of the H2L azo ligand and its complexes on the inhibition of bacterial or fungal growth were evaluated. The prepared complexes had enhanced activity against bacterial or fungal growth compared to the H2L azo ligand. 相似文献
218.
219.
在高剪切反应器(HSR)中研究了不同有机分散相对KHCO3/K2CO3溶液吸收CO2的强化效果,并考察了有机相与有机胺溶液复配使用对CO2吸收率的影响。实验结果表明:环己烷、正庚烷对KHCO3/K2CO3溶液吸收CO2的强化效果明显,甲苯、正辛醇对KHCO3/K2CO3溶液吸收CO2则没有明显的强化效果;CO2吸收率随HSR转速的增加而增加,随气液比、温度的增加而降低;环己烷对加入二乙醇胺活化的K2CO3溶液有较为明显的强化作用,CO2吸收率最高可提高23%。与文献中不同反应器的对比表明HSR对CO2具有较高的吸收效率。 相似文献
220.
Application of a dispersive micro‐solid‐phase extraction method for pre‐concentration and ultra‐trace determination of cadmium ions in water and biological samples
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Mohammad Behbahani Ali Veisi Fariborz Omidi Aminreza Noghrehabadi Ali Esrafili Mohammad Hossein Ebrahimi 《应用有机金属化学》2018,32(3)
A method for the trace determination of cadmium ions in water, human urine and human blood serum samples using ultrasonic‐assisted dispersive micro‐solid‐phase extraction (UA‐D‐μSPE) was developed. Silica‐coated magnetic nanoparticles were coated with polythiophene, and the resulting sorbent was characterized using thermogravimetry, differential thermal analysis, scanning electron microscopy, Fourier transform infrared spectrometry and X‐ray diffraction. Following UA‐D‐μSPE, cadmium ions were quantified using graphite furnace atomic absorption spectrometry. A Box–Behnken design was used for optimization of important sorption and desorption parameters in UA‐D‐μSPE: in the sorption step, pH of solution, sorption amount and sonication time for sorption; in the desorption step, concentration of eluent, volume of eluent and sonication time. The optimum conditions for the method were: pH of solution, 7.5; sonication time for sorption, 3 min; sorption amount, 35 mg; type and concentration of eluent, HCl and 1.1 mol l?1; volume of eluent, 360 μl; sonication time for desorption, 110 s. Under the optimized conditions the limit of detection and relative standard deviation for the detection of cadmium ions by UA‐D‐μSPE were found to be 0.8 ng l?1 and <6%, respectively. 相似文献