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Alain Tressaud Etienne Durand Christine Labrugère 《Journal of fluorine chemistry》2004,125(11):1639-1648
Due to their extreme reactivity, fluorine and fluorinated gases may be used to modify the surface properties of numerous materials. In the following, the surface fluorination of some carbon-based compounds (graphite, graphitised carbon fibres, carbon blacks and elastomers) using CF4 rf plasma technique and direct F2-gas fluorination is proposed. From XPS studies, the different types of CF bonding obtained in the materials after treatment have been correlated either to the physico-chemical characteristics of the pristine material or to the experimental parameters of the fluorination. Reaction mechanisms are proposed. 相似文献
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The characteristics of Al2O3 film grown by atomic‐layer deposition as blocking layer with and without fluorine plasma treatment were investigated based on a capacitor structure of Al/Al2O3/TaON/SiO2/Si. The physical structure was studied by transmission electron microscopy, and the chemical composition of the blocking layer was analyzed by X‐ray photoelectron spectroscopy and secondary ion mass spectroscopy. Moreover, the surface roughness of the blocking layer was investigated by atomic force microscopy. Compared with a capacitor with Al2O3 blocking layer, the one with fluorinated Al2O3 displayed higher programming/erasing speeds, better endurance property and better charge retention characteristic because the fluorination could reduce excess oxygen and traps in the blocking layer, thus forming a larger barrier height at the interface between the charge‐trapping layer and the blocking layer. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Dr. María Mar Quesada-Moreno Dr. Pablo Pinacho Dr. Cristóbal Pérez Dr. Marina Šekutor Prof. Dr. Peter R. Schreiner Prof. Dr. Melanie Schnell 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(20):6198-6203
Fluorinated derivatives of biological molecules have proven to be highly efficient at modifying the biological activity of a given protein through changes in the stability and the kind of docking interactions. These interactions can be hindered or facilitated based on the hydrophilic/hydrophobic character of a particular protein region. Diadamantyl ether (C20H30O) possesses both kinds of docking sites, serving as a good template to model these important contacts with aromatic fluorinated counterparts. In this work, an experimental study on the structures of several complexes between diadamantyl ether and benzene as well as a series of fluorinated benzenes is reported to analyze the effect of H→F substitution on the interaction and structure of the resulting molecular clusters using rotational spectroscopy. All experimentally observed complexes are largely dominated by London dispersion interactions with the hydrogen-terminated surface areas of diadamantyl ether. Already single substitution of one hydrogen atom with fluorine changes the preferred docking site of the complexes. However, the overall contributions of the different intermolecular interactions are similar for the different complexes, contrary to previous studies focusing on the difference in interactions using fluorinated and non-fluorinated molecules. 相似文献
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Dr. Lipiao Bao Baolin Zhao Vicent Lloret Prof. Dr. Marcus Halik Dr. Frank Hauke Prof. Dr. Andreas Hirsch 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(17):6766-6771
Patterned functionalization can, on the one hand, open the band gap of graphene and, on the other hand, program demanding designs on graphene. The functionalization technique is essential for graphene-based nanoarchitectures. A new and highly efficient method was applied to obtain patterned functionalization on graphene by mild fluorination with spatially arranged AgF arrays on the structured substrate. Scanning Raman spectroscopy (SRS) and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) were used to characterize the functionalized materials. For the first time, chemical patterning on the bottom side of graphene was realized. The chemical nature of the patterned functionalization was determined to be the ditopic scenario with fluorine atoms occupying the bottom side and moieties, such as oxygen-containing groups or hydrogen atoms, binding on the top side, which provides information about the mechanism of the fluorination process. Our strategy can be conceptually extended to pattern other functionalities by using other reactants. Bottom-side patterned functionalization enables utilization of the top side of a material, thereby opening up the possibilities for applications in graphene-based devices. 相似文献
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Shao-Bin Dou Xing-Liang Jia Zhi-Jun Liu Ya-Qi Meng Zheng-Rong Mo Gao-Nan Li Zhi-Gang Niu 《中国化学会会志》2020,67(9):1624-1630
Heteroleptic cyclometalated iridium(III) complexes ( Ir1 – Ir5 ) featuring piz-based ligands and acetylacetone ancillary ligand are synthesized and characterized. Their photophysical and electrochemical properties were studied, and DFT calculations were used to further support the experiment results. All the complexes emit yellow color with quantum yields of 12.2–56.5% in dichloromethane solution at room temperature, and the emission originates from a hybrid 3MLCT/3ILCT/3LLCT excited state. 相似文献
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We designed multiblock amphiphiles AmF and AmH , which consist of perfluorinated and non-fluorinated hydrophobic units, respectively. Absorption spectroscopy revealed that both amphiphiles are molecularly dispersed in organic solvent, while they form aggregates under aqueous conditions. Furthermore, we investigated whether AmF and AmH can be incorporated into DOPC lipid bilayer membranes, and found that the maximum concentration of AmF that can be incorporated into DOPC lipid bilayer membranes is 43 times higher than that of AmH . 相似文献
100.
The application of cyclopropenium ion as a phase transfer catalyst for benzylic fluorination in high yields is reported. Integral to the mechanisms of these fluorination reactions was the role of in situ derived cyclopropenium fluoride complexes, the existence of which was supported by 1H, 19F NMR and UV–Vis spectroscopy. Density functional theory calculations were applied to gain insight into the mechanism of these reactions. 相似文献