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991.
992.
Katsuhiko Tahara Eiji Nagahara Yasushi Itoi Satoru Nishiyama Shigeru Tsuruya Mitsuo Masai 《Reaction Kinetics and Catalysis Letters》1996,59(1):15-18
The conversion of a carboxylic acid was increased to 90% with 100% selectivity to the corresponding alcohol by calcination of the catalyst precursor, Sn/alumina, of Ru–Sn/alumina in the hydrogenation of the carboxylic acid. 相似文献
993.
Ryuji YokoyamaShunji Ito Tetsuo OkujimaTakahiro Kubo Masafumi YasunamiAkio Tajiri Noboru Morita 《Tetrahedron》2003,59(41):8191-8198
Amination of 2-substituted azulene was carefully examined using several types of amines, and the scope and limitation of substrates and reagents in these direct nucleophilic aminations were found. The synthesis of 2-aminoazulenes was successfully achieved by the reaction of 2-bromoazulene with several amines via palladium-catalyzed amination. 相似文献
994.
995.
K. Toi K. Oba Y. Maeda T. Ito T. Shirakawa I. Ikemoto T. Tokuda 《Journal of Polymer Science.Polymer Physics》1986,24(1):121-131
The precise pressure dependence of apparent diffusion and permeation coefficients was measured by using a microcomputer system for collecting and treating permeation data for CO2 in glassy poly(ethylene terephthalate) below 1 atm between 15 and 40°C. The partial immobilization model was used to determine the dual-mode sorption and mobility parameters. The curves calculated with these parameters were in excellent agreement with experimental data. These parameters were also compared with sorption parameters obtained from measurements at 30°C. There was a small difference between the values of the parameters obtained from these permeation data and those from sorption data which we had previously obtained. Relations between this difference and the method of determination of the parameters are discussed. 相似文献
996.
997.
We report room-temperature measurements of the high-energy electroluminescence (EL) of InAlAs/InGaAs HEMT's lattice-matched to InP substrates. We found that both the carrier temperature and the intensity obtained from the EL signal for the 1.4-1.7 eV energy range drastically increases with increasing the variation in the potential at the drain edge in the channel. The observed features are consistent with the results of the spatial distribution measurement, which indicates that the EL comes from the drain edge. We further compared the bias-voltage dependence of the high-energy EL and the recombination-induced EL measured for the same device, and discussed the origin and the threshold energy of the respective luminescent processes 相似文献
998.
999.
Hiroshi Ito Brian C. Trinque Paul Kasai C. Grant Willson 《Journal of polymer science. Part A, Polymer chemistry》2008,46(5):1559-1565
Electron‐deficient 2‐trifluoromethylacrylates (TFMA) undergo radical copolymerization with electron‐rich norbornene derivatives, vinyl ethers, and styrene derivatives, which can be described by the penultimate model much better than by the commonly employed terminal model. In an attempt to directly observe the effect of the CF3 group in the penultimate unit on the radical reactivity, we employed the Giese's mercury method. 4,4,4‐Trifluorobutyl and n‐butyl radicals produced from respective alkylmercuric chlorides were competitively reacted with t‐butyl 2‐trifluoromethylacrylate (TBTFMA) and t‐butyl methacrylate (TBMA) and the products analyzed with gas chromatography. While TBTFMA has been found to be about 24times more reactive than TBMA toward the n‐butyl radical, the former is about 12 times more reactive than the latter toward the 4,4,4‐trifluorobutyl radical. Thus, the reactivity of the propagating radical toward TBTFMA in comparison with TBMA is suppressed by a factor of two when the penultimate unit has the CF3 group. We observed a sextet electron spin resonance of the TFMA propagating radical with a coupling constant of ca. 25 gauss between the β‐proton and β‐fluorine. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1559–1565, 2008 相似文献
1000.
Noriya Okanouchi Hidehiro Honda Rie Ito Migaku Kawaguchi Koichi Saito Hiroyuki Nakazawa 《Analytical sciences》2008,24(5):627-630
In this study, a fast, simple and highly sensitive method that employs liquid phase microextraction (LPME)-GC/MS was developed to analyze trace benzophenones (BPs) in river-water samples. The tip of a 10-microl microsyringe filled with toluene (3 microl) was inserted into 2 ml of a river-water sample, and fixed at 5 mm below the water surface of the sample. A toluene droplet was made on the tip of the syringe, and extraction was conducted while agitating at 500 rpm for 15 min. After extraction, 2.0 microl of the extract was put into the syringe again, and directly introduced to GC/MS. The limits of detection (S/N = 3) and quantification (S/N >10) of BPs were 10 and 50 pg ml(-1), respectively. The results of a recovery test ranged over 93.3 - 101.1% (RSD, less than 10%; n = 6). The results of BPs determinations in the river-water samples showed that BPs (ND - 68.9 pg ml(-1)) were detected. 相似文献