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81.
Tatsuro Ouchi Hiroshi Sakamoto Yoshifumi Hosaka Minoru Imoto Tsutomu Iwamoto 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(8):1025-1038
Abstract The polymerization of some kinds of vinyl monomer was found to occur without an ordinary initiator in aqueous solutions of AB-type block or random copolymers of sodium methacrylate with styrene as a so-called “uncatalyzed polymerization.” Although the spin trapping technique showed that the initiation mechanism by the block copolymer was the same as that by the random copolymer, the initiating ability of the block copolymer was lower than that of the random copolymer. Such results are attributable to the difference in the incorporating ability of monomer into the micelles formed by the block copolymer and into the hydrophobic areas formed by the random copolymer. 相似文献
82.
Using p,p'-dimethoxydiphenyldiazomethane (DMDM) as initiator, the polymerization of methyl methacrylate (MMA) in benzene or in bulk was carried out. The initial rate of polymerization, Rp, was found to be expressed by the following equation: Rp = k[DMDM]0.53 [MMA]0.84 The polymerization was confirmed to proceed by a radical mechanism. The over-all activation energy for the polymerization in benzene was calculated as 19.3 kcal/mole. The rate of thermal decomposition of DMDM was also measured in benzene and the rate equation was obtained as follows: kd (sec?1) = 1.0 × 1015 exp (?29.1 kcal/RT) (for 50-80°C) Explanations of these observations are discussed in connection with those of the preceding papers. 相似文献
83.
Abstract The binary system of tetramethyl tetrazene (TMT) and Co(II) chloride was used as initiator of acrylonitrile (AN) in dimethylformamide. The initial rate of polymerization (Rp) was found to be expressed by Rp = k[TMT]0.62[Co(II) chloride]0.57 [AN]2.00 The polymerization was confirmed to proceed via a radical mechanism. The over-all activation energy for the polymerization was estimated as 15.1 kcal/mole. On the basis of these results and the product analysis of the reaction between the catalyst components in the absence of monomer, the initiation mechanism of the polymerization is discussed. 相似文献
84.
Tatsuro Ouchi Shinji Kitazaki Akinobu Kobayashi Minoru Imoto 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):1045-1059
The radical polymerization of methyl methacrylate (MMA) was carried out with the system of imidazole (Im), copper(n) chloride, and water at 85°C. The effects of the amount of each component on the conversion of MMA were investigated. The polymerization proceeded through a radical mechanism. The overall activation energy was estimated to be 28.7 kJ/mole. The conversion of MMA showed a maximum at pH 8-9 of the aqueous solution. The formation of a complex of CuCl2 with Im, water, and MMA was confirmed by electronic spectra. An initiation mechanism was proposed. 相似文献
85.
Copolymerization of an optically active N-(1-menthyl carboxylatomethyl)citraconimide (MCMCI) was carried out with methyl methacrylate (MMA) with azobisisobutyronitrile as the initiator in benzene at 50°C. All the copolymers obtained were optically active. After the removal of the optically active menthyl group, the hydrolyzed poly(MCMCI-co-MMA)'s still showed optical activity. The asymmetric induction to the copolymer main chain and the mechanism are discussed based on the measurements of optical rotatory dispersion and circular dichroism of the original and hydrolyzed copolymers. 相似文献
86.
87.
Tatsuro Ouchi Kazuo Hagita Hiroshi Sakamoto Minoru Imoto Tsutomu Iwamoto 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1651-1665
Abstract The polymerization of some kinds of vinyl monomer was found to occur in aqueous solutions of poly(ethylene glycol) diglycolic acid (PEG Acid) or sodium poly(ethylene glycol) diglycolate (PEG Acid Na) through radical mechanisms without any further initiator, as a so-called “uncatalyzed polymerization.” Although the initiating radical species for PEG Acid was determined to be the same as that for PEG Acid Na by means of the spin-trapping technique, the initiating ability of PEG Acid was higher than that of PEG Acid Na. These results are assumed to be attributable to the difference in the initiation mechanisms of the two systems and in the incorporating abilities of monomer into the hydrophobic areas formed by PEG Acid and PEG Acid Na. 相似文献
88.
Tatsuro Ouchi Hiroshi Sakamoto Masayasu Kubo Yoshifumi Hosaka Minoru Imoto 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):111-123
The radical polymerization of vinyl monomers initiated with several kinds of hydrophilic macromolecule was carried out in a magnetic field. The magnetic field promoted the polymerization; the conversion of monomers and the molecular weight of the polymers obtained increased with increasing field strength in the range of 0–0.1 T. The dependence of the composition and tacticity of the mother polymer on the magnitude of the magnetic field was studied. Using graft or block copolymers, which consisted of hard and soft segments, the effect of a magnetic field was further investigated. The degree of hardness and tightness of the hydrophobic areas (reaction areas) formed by the mother polymer in the aqueous solution was found to affect the magnetic field effect on the uncatalyzed polymerization. The overall activation energy obtained in the magnetic field was almost equal to that obtained without a magnetic field. 相似文献
89.
Masanori Miura Takanori Koike Tsukasa Ishihara Fukushi Hirayama Shuichi Sakamoto Minoru Okada 《合成通讯》2013,43(24):3809-3820
A one‐pot synthetic procedure for 2,2′‐disubstituted biaryls was developed via a Suzuki cross‐coupling reaction of aryl triflates in a biphasic solvent system. The effects of various bases and solvents were investigated. Results showed that the Na2CO3–toluene/H2O combination gave the highest yields. 相似文献
90.
A one-pot approach to indolo[2,1-b]quinazolines from indole-3-carbaldehydes through the Dakin oxidation was developed. It was shown that the reaction proceeded through the condensation of indole-3-carbaldehydes with isatoic anhydrides, derived in situ from indole-3-carbaldehydes by the Dakin oxidation, and further oxidation/cyclization steps. 相似文献