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排序方式: 共有614条查询结果,搜索用时 812 毫秒
71.
Takahito Itoh Motoka Ikeda Nobuyuki Hirata Yuji Moriya Zhaoyin Wen Yoshiaki Ichikawa Masataka Kubo Osamu Yamamoto 《Ionics》2002,8(1-2):44-52
Terminal-acetylated hyperbranched poly(ethylene glycol) derivatives containing diethylene, triethylene, and hexaethylene and
3,5-dioxybenzoate branching units (poly-Ac1a, poly-Ac1b, and poly-Ac1c) were synthesized. Electrochemical and thermal properties of the hyperbranched polymer electrolytes with lithium salts such
as LiCF3SO3 and LiN(CF3SO2)2, the composite hyperbranched polymer electrolytes with LiN(CF3SO2)2 containing α-LiAlO2 and γ-LiAlO2 fillers, and the hyperbranched polymer blended poly(ethylene oxide) electrolytes with LiN(CF3SO2)2 were investigated and discussed.
Paper presented at the 8th EuroConference on Ionics, Carvoeire, Algarve, Portugal, Sept. 16–22, 2001. 相似文献
72.
Polymer electrolytes plasticized with hyperbranched polymer for lithium polymer batteries 总被引:1,自引:0,他引:1
Hyperbranched polymers (HBPs) with different terminal groups and different ethylene oxide (EO) chain lengths were prepared,
and the influence of the HBP structures including molecular weights and molecular weight distribution on the ionic conductivity
and the mechanical property of the composite polymer electrolytes composed of poly (ethylene oxide) (PEO), HBP, BaTiO3 as a ceramic filler, and LiN(CF3SO2)2 as a lithium salt were investigated. It was found that the molecular weights of the HBP do not affect significantly the ionic
conductivity, but the molecular weight distribution might affect it, and also further branching at the terminals of the HBP
led to a decrease in the ionic conductivity. The HBP with longer EO chain length was effective for enhancement of the ionic
conductivity in comparison with the HBP with shorter one. The increase in cross-linkable groups (acryloyl group) at the terminals
of the HBP improved the tensile strength, but caused the ionic conductivity to decrease. Loosely cross-linked composite polymer
electrolyte showed higher ionic conductivity and higher tensile strength than no cross-linked one.
Paper presented at the Patras Conference on Solid State Ionics — Transport Properties, Patras, Greece, Sept. 14 – 18, 2004. 相似文献
73.
Kayoko Tahara Emi Makii Shiro Iijima Yoshihiro Abe Masataka Mochizuki 《Analytical sciences》2008,24(7):935-938
The electrochemical oxidation of (+/-)-alpha-tocopherol on a porous graphite electrode was performed in the presence of methanol, and successive separation and detection of the products were performed by an on-line liquid chromatography/mass spectrometry system. Three products were identified, one of which was determined to be alpha-tocopheryl quinone, because its m/z was 469 [M+Na](+). The other two products showed identical mass and UV spectra, and were suspected to be diastereomers of 9-methoxy-alpha-tocopheron, because their molecular weights were m/z 483 [M+Na](+), and also because it is known that the chemical oxidation of alpha-tocopherol by benzoyl peroxide or N-bromosuccinimide in the presence of methanol should provide 9-methoxy-alpha-tocopheron. To confirm that these two compounds were diastereomers, a circular dichroism detector was used. The signs of both peaks detected by the circular dichroism detector at 230 nm were opposite. In addition to observations of identical mass and ultraviolet spectra, these results indicated that the two products were diastereomers of 9-methoxy-alpha-tocopheron, whose stereochemistry is different at the newly generated chiral center of the 9-position. The on-line use of a circular dichroism detector with an electrochemical cell/liquid chromatography system may expand the utility of the system to study the metabolism of a chiral drug. 相似文献
74.
N-Alkyl-N(1-hydroperoxyalkyl)nitrosamines were synthesized from N,N-dialkylnitrosamines by lithiation with lithium diisopropylamide, followed by oxygenation with oxygen in good yields. 相似文献
75.
76.
Tomihiro Nishiyama Masataka Kushiyama Etsuo Ikemoto Fukiko Yamada 《Journal of heterocyclic chemistry》1984,21(1):37-39
Two isomeric 4-methyl-6-phenyl-5,6,7,8-tetrahydro-4H-1,3,2,6-dioxathiazocine 2-oxides were prepared, and their pmr and cmr spectra were examined. From the aromatic solvent shielding values and the magnitudes of the γ shifts, the title compounds are found to exist in the trans and cis forms in solution. 相似文献
77.
Kazuhiko Saigo Masataka Kubo Ru-Jang Lin Akira Youda Masaki Hasegawa 《Tetrahedron letters》1985,26(10):1325-1328
A novel cyclophane, 17, 17, 40, 40-tetramethyl-7, 30-dinitro-1, 10, 24, 33-tetraoxa[2.2.1.2.2.1] metaparaparametaparaparacyclophane, was synthesized by 2:2 cyclization of 3,5-bis(bromomethyl)nitrobenzene, derived from 3,5-dimethylnitrobenzene, and bisphenol A. The cyclophane was found to form 1:1 complex with benzene. 相似文献
78.
Using the values of the rotational molecular parameters (including cencrifugal distortion terms) of the H2
16O molecule, which can explain 12 observed transitions below 800 GHz, all rotational energy levels with normalized Boltzmann factors larger than 5×10–8 at 300°K are calculated. Probabilities of all possible electric dipole transitions among these states, 2277 lines, are calculated using the eigenfunctions thus obtained, and the permanent electric dipole moment of 1.8546 Debye. Assuming the single and full Lorentzian line forms, we calculated the absorption coefficient for millimeter to submillimeter region. Our result, using the single term Lorentzian line form, agrees quite well with experiment for 1 Torr of water vapor in 760 Torr air at 300°K. 相似文献
79.
80.