全文获取类型
收费全文 | 373篇 |
免费 | 6篇 |
专业分类
化学 | 257篇 |
晶体学 | 1篇 |
力学 | 11篇 |
数学 | 6篇 |
物理学 | 104篇 |
出版年
2023年 | 2篇 |
2022年 | 3篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 5篇 |
2017年 | 2篇 |
2016年 | 7篇 |
2015年 | 6篇 |
2014年 | 6篇 |
2013年 | 11篇 |
2012年 | 7篇 |
2011年 | 23篇 |
2010年 | 15篇 |
2009年 | 16篇 |
2008年 | 19篇 |
2007年 | 20篇 |
2006年 | 30篇 |
2005年 | 18篇 |
2004年 | 15篇 |
2003年 | 11篇 |
2002年 | 16篇 |
2001年 | 7篇 |
2000年 | 8篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1996年 | 5篇 |
1995年 | 6篇 |
1993年 | 6篇 |
1992年 | 9篇 |
1991年 | 6篇 |
1990年 | 9篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1986年 | 6篇 |
1985年 | 9篇 |
1984年 | 9篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1968年 | 6篇 |
1967年 | 3篇 |
1966年 | 2篇 |
1926年 | 1篇 |
1923年 | 1篇 |
排序方式: 共有379条查询结果,搜索用时 15 毫秒
11.
Diffusion coefficient of 36Cl in silver chloride was revealed to be about 1 x 10(-10)-4 x 10(-11) cm2 . s-1 in the range of 400 degrees C-200 degrees C by means of radioactive tracer measurements. Activation energy for diffusion was calculated about 0.13 eV. These results were different from those obtained by Maurer and Compton. 相似文献
12.
Ogawa T Araki M Miyamae T Okayama T Hagiwara M Sakurada S Morikawa T 《Chemical & pharmaceutical bulletin》2003,51(7):759-771
To improve the oral bioavailability of a dermorphin tetrapeptide analog, N(alpha)-1-iminoethyl-Tyr-D-MetO-Phe-MebetaAla-OH (III), which has a potent analgesic activity after oral administration, various derivatives were synthesized to increase lipophilicity by esterification of the C-terminal carboxyl group and/or acylation of the phenolic hydroxyl group on Tyr1. Antinociceptive activity was evaluated after subcutaneous or oral administration using the mouse tail pressure test. As a result, increased antinociceptive activity after oral administration as well as an improved ED50(p.o.)/ED50(s.c.) ratio, which is an indicator of oral bioavailability, were found for some compounds. With regard to the improvement of bioavailability, derivatives with acylation of the phenolic hydroxyl group on Tyr1 showed better results than derivatives with esterification of the C-terminal carboxyl group. In particular, an ED50(p.o.)/ED50(s.c.) ratio equivalent to that of morphine was found for an acetylated derivative, N(alpha)-1-iminoethyl-Tyr(COMe)-D-MetO-Phe-MebetaAla-OH (7a), as well as for a methoxycarbonylated derivative, N(alpha)-1-iminoethyl-Tyr(CO2Me)-D-MetO-Phe-MebetaAla-OH (7l). 相似文献
13.
14.
15.
Isozaki T Fujikawa T Takezoe H Fukuda A Hagiwara T Suzuki Y Kawamura I 《Physical review. B, Condensed matter》1993,48(18):13439-13450
16.
17.
Hisahiro Hagiwara Fumihide TakeuchiTakashi Hoshi Toshio SuzukiToshihiro Hashimoto Yoshinori Asakawa 《Tetrahedron letters》2003,44(11):2305-2306
1,9-Dideoxyforskolin 2 has been synthesized starting from ptychantin A 3. 相似文献
18.
19.
Kaoru Iwata Tsuneo Hagiwara Hiroshi Matsuzawa 《Journal of polymer science. Part A, Polymer chemistry》1986,24(5):1043-1051
The reciprocity effect under intense illumination was studied with photocrosslinkable polyesters of p-phenylenebis(α-cyanobutadiene carboxylic acid) (I), m-phenylenebis(α-cyanobutadiene carboxylic acid) (II), and p-phenylenebis(acrylic acid) (III), with an argon ion laser as a light source. The reciprocal sensitivities of I, II, and III were 5.0, 1800, and > 105 mJ/cm2, respectively. II and III required sensitization to enhance their sensitivities to a level at which reciprocity effects could be measured. I obeyed the reciprocity law over a wide range of exposure times from seconds to microseconds. Both II′, a copolyester of II, and III showed a dramatic decrease of sensitivity in high-intensity/short-time exposure when sensitized by 9,10-phenanthraquinone and pyrylium salts. 相似文献
20.