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91.
Kazuya Miki Yasunari Inamoto Shuka Inoue Takahiro Uno Takahito Itoh Masataka Kubo 《Journal of polymer science. Part A, Polymer chemistry》2009,47(21):5882-5890
A pentamethylcyclotrisiloxane moiety was introduced into cyclic polystyrene (cPSt) and cyclic PDMS (cPDMS) to obtain noncovalent cross‐linking agents, D3‐cPSt and D3‐cPDMS, respectively. Anionic ring‐opening polymerization of octamethylcyclotetrasiloxane (D4) in nitrobenzene was carried out in the presence of D3‐cPSt to obtain a cloudy white PDMS gel as a precipitation. On the other hand, bulk copolymerization of D3‐cPDMS with D4 proceeded in a homogeneous state to give a colorless transparent PDMS gel in high yield. The formation of mechanically linked PDMS with movable cross‐linking was indicated by control experiment. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5882–5890, 2009 相似文献
92.
Addition of the carbonium ion to vinylidene chloride to give α-substituted acetic acid discovered by Bott1,2 has been found of wide applicability. For example, the reaction of 1-bromo-, 1-hydroxy-, or 1-acetoxy-adamantane with vinylidene chloride in concentrated sulfuric acid gives a satisfactory yield of adamanty1-(1)-Acetic acid.3,4 相似文献
93.
Reactions of 1-haloadamantane with aromatic compounds such as benzene, toluene, bromobenzene and so on in the presence of Friedel-Craft type catalysts to afford adamantyl-(1)-benzene derivatives have been reported1 already, but little is known about the reaction with phenolic cómpounds, the only example being the synthesis of 1,3-bis-(p-hydroxyphenyl)-5,7-dimethyl-adamantane by the reaction of 1,3-dibromo-5,7-dimethyladamantane and phenol reported in a patent literature.2 相似文献
94.
Hideko T. Oyama Mai Sekikawa Yasunari Ikezawa 《Journal of Macromolecular Science: Physics》2013,52(3):463-483
The relationship between the interface structure and the macroscopic properties of composites composed of isotactic polypropylene (iPP) and magnesium hydroxide (MH) was investigated with a focus on mechanical properties, thermal stability, and flame retardancy. Surface treatment of MH was carried out using dodecanoic acid (DA) and dodecylphosphate (DP), both of which interacted with MH to form submonolayer coverages. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) revealed that both organic reagents adhere to the MH surface via ionic interactions. Even low amounts of organic reagents on the MH surface were sufficient to improve the mechanical, thermal, and flame retardant properties of the composites. The incorporation of 1.8 wt% of DP in (70/30) iPP/MH-DP composite decreased the peak heat release rate (PkHRR) to 39% compared with that of neat iPP. Since the effects of DA with the same dodecyl chains were not significant, it is concluded that the phosphate groups in DP provide flame retardancy. 相似文献
95.
Mohamed Mohamedi Yasunari Hisamitsu Takashi Kudo Takashi Itoh Isamu Uchida 《Journal of Solid State Electrochemistry》2001,5(7-8):538-545
The oxidation behavior of nickel in Li+K carbonate melt is followed by measuring the open-circuit potential and by electrochemical
impedance spectroscopy under an O2+CO2 gas mixture in the ratio 90/10 at a total pressure of 1 atm at 650 °C. X-ray diffraction (XRD) and energy-dispersive spectroscopy
are employed for qualitative and quantitative analyses of the different compounds involved during the oxidation of nickel.
Atomic force microscopy is used for both imaging the evolution of the oxide layer and determining its surface roughness. The
in situ oxidation process of nickel demonstrates three stages: rapid formation of a compact surface oxide (first stage), thicker
oxide layer (second stage), and a porous oxide structure (third stage). The lithiation reaction has been identified to occur
during the second stage. Formation of an intermediate and unstable compound, namely NiCO3, has been confirmed by XRD.
Electronic Publication 相似文献
96.
97.
98.
Inamoto K Asano N Kobayashi K Yonemoto M Kondo Y 《Organic & biomolecular chemistry》2012,10(8):1514-1516
An efficient coupling of terminal alkynes and CO(2) in the presence of alkyl halides can be achieved under ambient conditions using a copper/phosphine catalyst system, providing facile access to a variety of functionalised alkyl 2-alkynoates. 相似文献
99.
Hiratsuka H Horiuchi H Furukawa Y Watanabe H Ishihara A Okutsu T Tobita S Yoshinaga T Shinohara A Tokitoh N Oba M Nishiyama K 《The journal of physical chemistry. A》2006,110(11):3868-3874
Photophysical and photochemical processes of 9-methyl- and 9-phenyl-9,10-dihydro-9-silaphenanthrene derivatives have been studied at room temperature and 77 K in comparison with the carbon analogue, 9,10-dihydrophenanthrene. These 9,10-dihydro-9-silaphenanthrene derivatives show smaller fluorescence quantum yield and remarkably larger Stokes shifts than those of the carbon analogue. In contrast, their phosphorescence quantum yields are two times larger than those of the carbon analogue, although the absolute value is not so large (approximately 0.1). Reaction products and intermediates produced by the 266 nm light photolysis have been studied, and it has been confirmed that 9-methyl- and 9-phenyl-9-silaphenanthrenes have been photochemically formed in methylcyclohexane at 77 K, in addition to the formation of radical cations of 9,10-dihydro-9-silaphenanthrene derivatives and the carbon-centered radical: 9-hydro-9-silaphenanthrenyl radical. 相似文献
100.
The isomeric states and intermolecular packing of tris(8-hydroxyquinoline) aluminum(III) (Alq(3)) in the alpha-, gamma-, and delta-crystalline forms and in the amorphous state, which are important for understanding the light-emitting and electron-transport properties, have been analyzed by CP/MAS (13)C NMR. This simple NMR experiment shows that the isomeric state of alpha- and amorphous Alq(3) is meridional, whereas that of gamma- and delta-Alq(3) is facial. In the amorphous Alq(3), the inclusion of facial isomers has been under debate. Our experiments show that meridional isomers are dominant in the amorphous Alq(3), although the existence of facial isomers cannot be completely denied. The local structure of amorphous Alq(3) is similar to that of alpha-Alq(3) and is significantly different from those of gamma- and delta-Alq(3). Among these Alq(3) samples, the effect of intermolecular interaction is not found only for gamma-Alq(3). This finding can explain the good solvent solubility of gamma-Alq(3), compared with the other crystalline forms. It is also shown that the structures are locally disordered not only for amorphous Alq(3) but also for alpha-Alq(3), although clear X-ray diffraction peaks are observed for alpha-Alq(3). In contrast, the local structures of gamma- and delta-Alq(3) are well defined. A clear relation is found between the spectral patterns of CP/MAS (13)C NMR and the fluorescence wavelengths; the samples, which consist of facial isomers, show blue-shifted fluorescence compared with those of meridionals. 相似文献