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61.
Nakao Y Imanaka H Sahoo AK Yada A Hiyama T 《Journal of the American Chemical Society》2005,127(19):6952-6953
Alkenyl- and aryl[2-(hydroxymethyl)phenyl]dimethylsilanes, highly stable tetraorganosilicon reagents, are found to react with aryl and alkenyl iodides in the presence of a palladium catalyst and K2CO3 as a base, significantly milder conditions compared with those ever reported for the silicon-based cross-coupling reactions. The reaction tolerates a wide range of functional groups, including silyl protectors, and allows a gram-scale synthesis to recover and reuse the silicon residue. 相似文献
62.
Vera Yu Mishina Mikhail K. Gratchev Konstantin L. Anfilov Il'dar G. Mustafin Anna R. Bekker Edward E. Nifantyev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The effective methods of phosphorylation of complex systems with specifically orientated in space hydroxyl groups, namely dianhydro-D-mannitol(A), -D-sor-bitol(B), cyclodextrines(C), and cellulose(D) (A-D, where R=H), have been elaborated. 相似文献
63.
Hiroya Takada Yoshiaki Nishibayashi Kouichi Ohe Sakae Uemura 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):363-364
Prochiral sulfides reacted with Phl=NTs in the presence of a catalytic amount of Cu(I) salt together with a chiral 4,4′-disubstituted bis(oxazoline) ligand to afford the corresponding chiral sulfimides. 相似文献
64.
65.
Keiichi Kimura Akira Matsui Yoshiaki Inaki Kiichi Takemoto 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(8):1231-1241
Polymerization of acrylonitrile initiated by triazole-copper(II) complexes was studied in dimethylsulfoxide solution. It was found that the polymerization proceeds by a free radical mechanism; however, the complexes can hardly homopolymerize methyl methacrylate and styrene. Ability of the complexes to initiate polymerization seems to depend on the substituents of triazole, the sort of solvents, and the counterions of copper(n) salts. From the data of visible spectroscopy and the spin trapping, the initiation mechanism was discussed in terms of reduction of copper(II) followed by forming active species. 相似文献
66.
67.
Jun TakayamaSeiko Fukuda Yoshiaki SugiharaAkihiko Ishii Juzo Nakayama 《Tetrahedron letters》2003,44(28):5159-5162
Hetero Diels-Alder reactions of 3,4-di-tert-butylthiophene 1-oxide (1) with thioaldehydes and thioketones take place exclusively, except the reaction with thiobenzophenone, at the syn-π-face of 1 with respect to the SO bond. The π-face selectivity was explained in terms of the extent of conformational changes of 1 that are brought about in the process to the transition states. 相似文献
68.
Nomoto A Mitsuoka H Ozeki H Kobuke Y 《Chemical communications (Cambridge, England)》2003,(9):1074-1075
Introducing a porphyrin bearing electron acceptor onto a self-assembled monolayer (SAM) using a supramolecular method to form a hetero-dimer increased the photocurrent value compared with using porphyrin without an electron acceptor. 相似文献
69.
Porphyrin macrocycles composed of five and six units of m-gable imidazolylporphyrinatozinc (1-Zn) were synthesized by self-assembled cyclization followed by ring-closing metathesis linkings. Each porphyrin macrocycle was isolated by GPC chromatography, and their molecular weights were determined by MALDI-TOF mass spectroscopy. These structures represent mimics of light-harvesting complexes in photosynthetic bacteria. [structure: see text] 相似文献
70.
Yoshiaki Hidaka Hiromitsu Masaoka Hidekazu Oshita Takuji Nakamura Koji Tanaka Hiroyuki Kawano 《国际化学动力学杂志》1992,24(10):871-885
The thermal decomposition of vinylacetylene (C4H4) was studied behind reflected shock waves using both a single-pulse method (reaction time between 0.8 and 3.3 ms) and a time-resolved UV-absorption method (230 nm). The studies were done over the temperature range of 1170–1690 K at the total pressure range of 1.3–2.3 atm. The mechanism was used to interpret both the early and late stages of vinylacetylene decomposition at the high temperatures. It was confirmed that C4H4 dissociation proceeded through the following three channels. The rate constant expression of reaction (1) was determined as k1 = 6.3 × 1013 exp(?87.1 kcal/RT) s?1. The rate constants of the succeeding reactions (chain reaction, C4H4 + H → i-C4H3 + H2 and C4H4 + H → C2H2 + C2H3 and decomposition reactions of free radicals, i-C4H3 + M → C4H2 + H + M) were confirmed or estimated. © John Wiley & Sons, Inc. 相似文献