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181.
Masaaki Yoshifuji Ichiro Shima Naoki Inamoto Tomoo Aoyama 《Tetrahedron letters》1981,22(32):3057-3060
ab initio Calculation of the benzene skeletons of the titled compound indicated that the molecule suffers 61.4 kcal/mol higher energy than that of flat benzene rings and that the boat benzene form is even more stable than the envelope or chair form benzene. 相似文献
182.
Copper nanoparticles on hydrotalcite as a heterogeneous catalyst for oxidant-free dehydrogenation of alcohols 总被引:2,自引:0,他引:2
Mitsudome T Mikami Y Ebata K Mizugaki T Jitsukawa K Kaneda K 《Chemical communications (Cambridge, England)》2008,(39):4804-4806
We have developed a highly efficient heterogeneous catalytic system using hydrotalcite-supported Cu nanoparticles (Cu/HT) that can successfully promote the oxidant-free dehydrogenation of various alcohols under liquid-phase conditions. 相似文献
183.
Mizugaki T Murata M Fukubayashi S Mitsudome T Jitsukawa K Kaneda K 《Chemical communications (Cambridge, England)》2008,(2):241-243
Dendron stabilised Pd nanoparticles were prepared using the self-assembly of dendrons, which could catalyze a highly selective hydrogenation of dienes and acetylenes to monoenes. 相似文献
184.
Three-dimensional accurate potential energy surfaces around the local minima of NO2− and NO2 were calculated with the SAC/SAC-CI analytical energy gradient method. Therefrom, the ionization photoelectron spectra of NO2−, the equilibrium geometries and adiabatic electron affinity of NO2, and the vibrational frequencies including harmonicity and anharmonicity of NO2− and NO2 were obtained. The calculated electron affinity was in reasonable agreement with the experimental value. The SAC-CI photoelectron spectra of NO2− at 350 K and 700 K including the rotational effects were calculated using the Franck–Condon approximation. The theoretical spectra reproduced well the fine experimental photoelectron spectra observed by Ervin et al. (J. Phys. Chem. 1988, 92, 5405). The results showed that the ionizations from many vibrational excited states as well as the vibrational ground state are included in the experimental photoelectron spectra especially at 700 K and that the rotational effects are important to reproduce the experimental photoelectron spectra of both temperatures. The SAC/SAC-CI theoretical results supported the analyses of the spectra by Ervin et al., except that we could show some small contributions from the asymmetric-stretching mode of NO2−. © 2018 Wiley Periodicals, Inc. 相似文献
185.
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187.
ABSTRACT We tested boron-doped diamond (BDD) synthesized by chemical vapor deposition (CVD) as a heating element in a multi-anvil apparatus. We succeeded in manufacturing BDD into a tubular shape by laser cutting and electric discharging machining. The BDD tube shaped by the electric discharging machining was contaminated by discharging electrode materials (Mo and W), which affected the heating performance. The laser-cut BDD tube has a clean surface and, therefore, had a good heating performance. We succeeded in generating temperature as high as 2670?K at a pressure around 30?GPa with laser-cut heater. Heating reproducibility was confirmed through repeated heating and cooling cycles. The recovered sample shows that a higher temperature generation above 2670?K was prevented by eutectic melting of ZrO2 thermal insulator and Al2O3 sample. Owing to the commercial availability with a reasonable price, CVD–BDD heaters are more practical than a high-pressure synthesized BDD heaters for wide applications. 相似文献
188.
Cyclodextrins (CD's) were visualized by postcolumn mixing with 2-p-toluidinylnaphthalene sulfonate (TNS) in liquid chromatography. The indirect detection is based on fluorescence enhancement due to the formation of an inclusion complex between TNS and CD's. β-CD gave larger signal intensity than α- and γ-CD. Different selectivities were observed for alkyl-bonded silica stationary phases with different chain length. 相似文献
189.
Takahide Mizawa Katsuhiko Takenaka Tomoo Shiomi 《Journal of polymer science. Part A, Polymer chemistry》1999,37(17):3464-3472
In order to synthesize end-functionalized polymers with conjugated dienyl groups, living polymeric anions of polystyrene and polyisoprene were allowed to react with 5-bromo-1,3-pentadiene, 1, and 7-bromo-1,3-heptadiene, 2. The reaction of polystyryl anion and/or polyisoprenyl anion with 1 gave polymers whose end-functionalities were 65–80% regardless of the reaction conditions. On the other hand, almost quantitative functionalization was achieved when a large excess amount of 2 was used as a terminator. When 1,1-diphenylalkyl anion and enolate anion derived from t-butyl methacrylate were used, the degree of end-functionality were 70–80% at best. The resulting end-functionalized polymers were characterized by size exclusion chromatography (SEC), 1H and 13C-NMR and thin layer chromatography coupled with a flame ionization detector (TLC-FID). © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3464–3472, 1999 相似文献
190.
Tomoo Shiomi Masao Tohyama Masaki Endo Tsukasa Sato Kiyokazu Imai 《Journal of Polymer Science.Polymer Physics》1996,34(15):2599-2606
Intermolecular interactions in random copolymer systems depend on the copolymer composition as being observed as a miscibility window in the random copolymer blends. The copolymer composition dependencies of the Flory-Huggins χ parameter and the heats of mixing ▵HM(∞) at infinite dilution were studied for the solutions of poly(methyl methacrylate-ran-n-butyl methacrylate) (MMAnBMA) in cyclohexanone (CHN). The copolymer composition dependencies of χ obtained from osmotic pressures and of ▵HM(∞) measured with a microcalorimeter were concave curves. This suggests that the random copolymers MMAnBMA interact with CHN more attractively than do the homopolymers PMMA and PnBMA. This is caused by the repulsion effect between the MMA and nBMA segments. The equation-of-state theory extended to the random copolymer systems by us reproduced fairly well these thermodynamic properties. The χ parameter for the PMMA/PnBMA blends was calculated using the equation-of-state theory with the MMA/nBMA intersegmental parameters employed for the above random copolymer solutions in CHN. The χ value calculated thus was in satisfactory agreement with that obtained from the random copolymer solutions using the Flory-Huggins theory extended to multicomponent systems. © 1996 John Wiley & Sons, Inc. 相似文献