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11.
Prof. Dr. Skye Fortier José Veleta Dr. Amélie Pialat Jennifer Le Roy Kamran B. Ghiassi Prof. Dr. Marilyn M. Olmstead Dr. Alejandro Metta‐Magaña Prof. Dr. Muralee Murugesu Prof. Dr. Dino Villagrán 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):1931-1936
After more than 50 years, the synthesis and electronic structure of the first and only reported “U0 complex” [U(bipy)4] ( 1 ) has been reinvestigated. Additionally, its one‐electron reduced product [Na(THF)6][U(bipy)4] ( 2 ) has been newly discovered. High resolution crystallographic analyses combined with magnetic and computational data show that 1 and its derivative 2 are best described as highly reduced species containing mid‐to‐high‐valent uranium ligated by redox non‐innocent ligands. 相似文献
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Togashi DM Romão RI Gonçalves da Silva AM Sobral AJ Costa SM 《Physical chemistry chemical physics : PCCP》2005,7(22):3874-3883
Langmuir monolayers (LM) and Langmuir-Blodgett (LB) films of pure lipophilic meso-tetra(4-dodecylaminosulfophenyl)porphyrin (PC12) and mixed with the anionic surfactant sodium hexadecylsulfate (SHS) were studied. The molecular packing and structure of PC12 and PC12-4SHS with variable surface pressure were investigated by surface pressure-area measurements, steady-state absorption, fluorescence emission and anisotropy, as well as by fluorescence lifetime imaging microscopy (FLIM). At low surface pressure, the porphyrin molecules are organized with the rings tilted on the water surface whereas at high surface pressure the porphyrin rings achieve a more perpendicular arrangement. Using the FLIM images a gradual change of aggregates into large "islands" is observed. Different patterns are observed in the pure PC12 multilayer films (n = 3 and 5) with ordered patches superimposed which are not observed in the PC12-4SHS multilayer LB films. 相似文献
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Vieira HS Takahashi JA Gunatilaka AA Boaventura MA 《Magnetic resonance in chemistry : MRC》2006,44(2):146-150
A highly rearranged novel dilactone was the single product isolated from Baeyer-Villiger oxidation of a norketone prepared from grandiflorenic acid, a natural kaurane diterpene. The complete 1H and 13C NMR assignment is presented for this novel compound that showed discrete in vitro antibacterial activity. 相似文献
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A practical, chromatography-free synthesis of potent cathepsin K inhibitor 1 is described. The addition of 4-bromophenyllithium to an alpha-trifluoromethylimine derived from commercially available (S)-leucinol was accomplished in a highly diastereoselective manner (97.6% de, 91% yield). Subsequent Suzuki cross-coupling afforded biaryl 7. Oxidation of the alcohol and sulfide functionalities led to the formation of carboxylic acid 8. Crystallization of 7 and acid 8 as its dicyclohexylamine salt gave excellent impurity rejection. The final amide coupling with commercially available aminoacetonitrile hydrochloride afforded 1 in excellent purity (99.6A% by HPLC, 100% de, <3 ppm Pd, W, Cr). 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - A thin-layer chromatographic method with densitometric UV detection at 286 nm after ethyl acetate extraction is described for... 相似文献
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The second paper of the series devoted to the preparation and characterization of vinyl and hydrido‐functionalized silicones proposes readily available techniques to polymerize commercially available cyclosiloxanes. This study is divided into two main sections: one relies on the synthesis of various functional silicone oils by heterogeneous cationic ring opening polymerization (ROP) of cyclotetrasiloxanes (D4, D) and appropriate 1,3‐difunctional disiloxanes; the second part describes the anionic ROP of hexamethylcyclotrisiloxane (D3) initiated by potassium silanolates to prepare both homo‐ and hetero‐vinyl functionalized silicones. The conditzions in which polymers with desired molecular weights can be obtained have been established and some kinetic considerations are also reported. The width of the final molar mass distribution ranged between 1.5 and 1.8, respectively, in any case narrower than the mixtures proposed by different providers (around 2). Polymers were characterized by different techniques of size exclusion chromatography (SEC), proton and silicon nuclear magnetic resonance (1H and 29Si NMR), and mass spectrometry. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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