全文获取类型
收费全文 | 1429篇 |
免费 | 32篇 |
国内免费 | 6篇 |
专业分类
化学 | 1105篇 |
晶体学 | 10篇 |
力学 | 8篇 |
数学 | 93篇 |
物理学 | 251篇 |
出版年
2021年 | 7篇 |
2020年 | 14篇 |
2019年 | 16篇 |
2018年 | 13篇 |
2017年 | 9篇 |
2016年 | 22篇 |
2015年 | 22篇 |
2014年 | 28篇 |
2013年 | 53篇 |
2012年 | 62篇 |
2011年 | 81篇 |
2010年 | 43篇 |
2009年 | 38篇 |
2008年 | 70篇 |
2007年 | 88篇 |
2006年 | 79篇 |
2005年 | 62篇 |
2004年 | 71篇 |
2003年 | 69篇 |
2002年 | 62篇 |
2001年 | 20篇 |
2000年 | 25篇 |
1999年 | 13篇 |
1998年 | 23篇 |
1997年 | 12篇 |
1996年 | 24篇 |
1995年 | 11篇 |
1994年 | 23篇 |
1993年 | 17篇 |
1992年 | 22篇 |
1991年 | 23篇 |
1990年 | 13篇 |
1989年 | 8篇 |
1988年 | 15篇 |
1987年 | 11篇 |
1986年 | 16篇 |
1985年 | 33篇 |
1984年 | 31篇 |
1983年 | 15篇 |
1982年 | 15篇 |
1981年 | 23篇 |
1980年 | 34篇 |
1979年 | 24篇 |
1978年 | 20篇 |
1977年 | 9篇 |
1976年 | 11篇 |
1975年 | 10篇 |
1974年 | 13篇 |
1973年 | 13篇 |
1972年 | 6篇 |
排序方式: 共有1467条查询结果,搜索用时 15 毫秒
1.
Watanabe Sou Senzaki Tatsuya Shibata Atsuhiro Nomura Kazunori Takeuchi Masayuki Nakatani Kiyoharu Matsuura Haruaki Horiuchi Yusuke Arai Tsuyoshi 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(3):1273-1277
Journal of Radioanalytical and Nuclear Chemistry - Extraction chromatography flow-sheet employing octyl(phenyl)-N,N-diisobutylcarbonoylmethylphosphine oxide and bis(2-ethylhexyl) hydrogen phosphate... 相似文献
2.
We study the nonrelativistic limit of the Cauchy problem for the nonlinear Klein-Gordon equation and prove that any finite
energy solution converges to the corresponding solution of the nonlinear Schr?dinger equation in the energy space, after the
infinite oscillation in time is removed. We also derive the optimal rate of convergence in .
Received: 13 July 2000 / Published online: 1 February 2002 相似文献
3.
Daisuke Matsuura 《Tetrahedron letters》2006,47(9):1371-1374
An efficient and stereodefined strategy is described for the asymmetric synthesis of a new styryllactone from the stem bark of Goniothalamus cardiopetalus, cardiobutanolide. The synthetic process is based on requisite manipulation of the functionalized bicyclic lactol-lactone intermediate incorporating the glucuronolactone-derived skeleton in a complete stereoselective manner. 相似文献
4.
Low-loss and rugged distal tips for CO2 laser have been proposed and fabricated based on a commercially available stainless steel (St) pipe. A method of smoothening the inner surface of the St pipe with a rough inner surface is put forward. Fabrication parameters, transmission properties, and mechanical strength of the cyclic olefin polymer-coated silver hollow St distal tip are experimentally discussed. 相似文献
5.
6.
T Niwa H Yoshizumi A Tatematsu S Matsuura T Nagatsu 《Journal of chromatography. A》1989,493(2):347-352
7.
Tohru OishiHiroshi Tsuchikawa Michio Murata Manabu YoshidaMasaaki Morisawa 《Tetrahedron letters》2003,44(34):6387-6389
A chemoattractant candidate named sperm-activating and attracting factor (SAAF) from the eggs of ascidian Ciona intestinalis, was synthesized from chenodeoxycholic acid in 16 steps. The present synthesis led to the unambiguous structure determination of SAAF to be (3R,4R,7R,25S)-3,4,7,26-tetrahydroxycholestane-3,26-disulfate. The synthetic pure specimen was also used to confirm the dual sperm-activating and attracting activity. 相似文献
8.
Takuya Hasegawa Hirotaka Matsuura Kazumi Inagaki Hiroki Haraguchi 《Analytical sciences》2003,19(1):147-150
The major-to-ultratrace elements in human bone-marrow fluid were determined by ICP-AES (inductively coupled plasma atomic emission spectrometry), and ICP-MS (inductively coupled plasma mass spectrometry). The bone-marrow fluid sample was centrifuged prior to acid digestion to exclude the bone piece from bone marrow, and then digested with nitric acid. As a result, 20 elements could be determined over the concentration range from 1610 microg g(-1) for Na to 0.00043 microg g(-1) for W. It was found that Fe, Zn and Sb were enriched by ca. 264-, 7- and 15-fold, respectively, in bone-marrow fluid, compared to those in human blood serum. Alkali metals (K, Rb, Cs), except for Na, were also significantly enriched in bone-marrow fluid. Furthermore, the concentrations of various elements, such as Fe, P, Al, Zn, Cu, Se, Zr, Sn, Ag and W, were significantly higher than those in open seawater. 相似文献
9.
Kazuhiko Hashimoto Sirinat Wibullucksanakul Mitsuyasu Matsuura Masahiko Okada 《Journal of polymer science. Part A, Polymer chemistry》1993,31(12):3141-3149
Ring-opening polyaddition of a saccharic acid dilactone prepared from D-glucose, D-glucaro-1,4 : 6,3-dilactone, with several alkylenediamines proceeded at room temperature with no catalyst. The resulting new polyamides carrying many pendant hydroxyl groups, poly(alkylene D-glucaramide)s, were more amorphous and hydrophilic than the corresponding nylons having no hydroxyl groups, and were hydrolyzed more easily than the latter in an acidic condition. The ring-opening ability of D-mannaro-1,4:6,3-dilactone, which was another saccharic acid dilactone obtained from D-mannitol, was found to be lower than that of the D-glucaric analogue. © 1993 John Wiley & Sons, Inc. 相似文献
10.
Katsumasa Iwai Yi-Wei Shi Mitsunobu Miyagi Yuji Matsuura 《Optics & Laser Technology》2007,39(8):1528-1531
An improved coating method was proposed in order to form a uniform polymer layer in the fabrication of cyclic olefin polymer-coated silver (COP/Ag) hollow fiber. A COP solution was flowed in a closed loop, in which the silver-coated tube was used as a part of the loop. Owing to the constant flowing speed of the COP solution and the airtight flowing environment, a COP layer was uniformly formed. The hollow fibers attain high performance and deliver multi-wavelength laser light from the infrared to the visible simultaneously. The method was successfully applied to the fabrication of practical hollow fibers with 2 m length for the near and mid-infrared lasers. 相似文献