全文获取类型
收费全文 | 1345篇 |
免费 | 21篇 |
国内免费 | 2篇 |
专业分类
化学 | 977篇 |
晶体学 | 22篇 |
力学 | 12篇 |
数学 | 43篇 |
物理学 | 314篇 |
出版年
2023年 | 7篇 |
2022年 | 10篇 |
2021年 | 11篇 |
2020年 | 13篇 |
2019年 | 15篇 |
2018年 | 10篇 |
2017年 | 7篇 |
2016年 | 14篇 |
2015年 | 13篇 |
2014年 | 24篇 |
2013年 | 55篇 |
2012年 | 66篇 |
2011年 | 88篇 |
2010年 | 45篇 |
2009年 | 37篇 |
2008年 | 77篇 |
2007年 | 76篇 |
2006年 | 81篇 |
2005年 | 58篇 |
2004年 | 62篇 |
2003年 | 63篇 |
2002年 | 47篇 |
2001年 | 31篇 |
2000年 | 25篇 |
1999年 | 25篇 |
1998年 | 17篇 |
1997年 | 15篇 |
1996年 | 19篇 |
1995年 | 17篇 |
1994年 | 17篇 |
1993年 | 28篇 |
1992年 | 29篇 |
1991年 | 26篇 |
1990年 | 22篇 |
1989年 | 22篇 |
1988年 | 19篇 |
1987年 | 11篇 |
1986年 | 9篇 |
1985年 | 24篇 |
1984年 | 20篇 |
1983年 | 15篇 |
1982年 | 7篇 |
1981年 | 11篇 |
1980年 | 16篇 |
1979年 | 10篇 |
1978年 | 8篇 |
1977年 | 12篇 |
1975年 | 5篇 |
1974年 | 8篇 |
1973年 | 7篇 |
排序方式: 共有1368条查询结果,搜索用时 15 毫秒
1.
Yoshio Suzuki Noriyuki Tanji Chikako Ikeda Aki Honda Kenji Ookubo Daniel Citterio Suzuki Koji 《Analytical sciences》2004,20(3):475-482
Novel labeling reagents, called MS probes, which possess a positively charged quaternary amine moiety and can transform a neutral analyte into a charged compound by simply mixing with the analyte and allowing the mixture to stand from several minutes to 30 min at room temperature or while heating to 50 degrees C, were designed and synthesized for the highly sensitive detection of carbonyl, alcohol, carboxylic acid and primary amine samples by electrospray ionization mass spectrometry (ESI-MS). The positively charged products can be detected with high sensitivity in an ESI-MS system, which is the most popular liquid MS instrument. All of the labeled products showed a remarkably large increase in the molecular-ion peak abundance detection sensitivity of over 500-fold at picomolar concentration levels compared to that of unlabeled analytes in an ESI-MS system. These MS probes, used together with liquid MS detection, are widely applicable as a convenient method for the highly sensitive detection of less than picomolar levels of analytes, and therefore greatly enhance the power of ESI-MS analysis. 相似文献
2.
3.
Statistical Inference for Stochastic Processes - 相似文献
4.
5.
Noriyuki Mizoguchi 《Journal of mathematical chemistry》1991,7(1):325-340
Generalized graphs represent Hückel-type and Möbius-type polycyclic conjugated systems. We show that the number of generalized graphs with different spectra for a given parent graph is not larger than 2
N(R) and is equal to 2
N(R) if no two rings are equivalent,N(R) being the number of rings (fundamental circuits) in the parent graph. We demonstrate that the rule for the stability of generalized graphs, proved in a previuos paper, and the information on the relative magnitudes of the effects of individual circuits enable one to predict the stabilities of generalized graphs without performing numerical calculations. 相似文献
6.
G. M. Luke L. P. Le B. J. Sternlieb Y. J. Uemura J. H. Brewer R. Kadono R. F. Kiefl S. R. Kreitzman T. M. Riseman C. E. Stronach M. Davis S. Uchida H. Takagi Y. Tokura Y. Hidaka T. Murakami E. A. Early J. T. Markert M. B. Maple C. L. Seaman 《Hyperfine Interactions》1991,63(1-4):311-317
We report muon spin relaxation/rotation measurements on sintered powder samples of Nd2−x
Ce
x
CuO4−y
and a large single crystal of Nd2CuO4−y
. We find an electronic phase diagram which is quite similar to that of hole-doped superconductors such as La2−x
Sr
x
CuO4−y
, although the doping of electrons into the system is less efficient in destroying the static moments on the copper spins.
Static magnetic order in Nd2CuO4−y
appears below about 250 K, and two spin reorientations are seen atT=75 K andT=35 K. Measurements of the magnetic field penetration depth have been unsuccessful due to the rare-earth paramagnetism of
these materials. 相似文献
7.
K. Takamiya T. Fukunishi R. Tsujito S. Fukutani T. Takahashi S. Shibata S. Uchida 《Journal of Radioanalytical and Nuclear Chemistry》2007,273(1):195-198
The adsorption behavior of fission products to various soils was studied using a multitracer. The multitracer was prepared
by neutron irradiation of 235U. Distribution coefficients of fission products were obtained for seventeen kinds of Japanese soils. It was found that zirconium,
niobium, and rare earth elements show high distribution coefficients for all soil samples, however, elements like alkali metals
show varied values. 相似文献
8.
9.
10.
Synthesis and hypotensive activity of benzopyran derivatives 总被引:1,自引:0,他引:1
M Shiratsuchi K Kawamura T Akashi M Fujii H Ishihama Y Uchida 《Chemical & pharmaceutical bulletin》1987,35(2):632-641