全文获取类型
收费全文 | 738篇 |
免费 | 15篇 |
国内免费 | 7篇 |
专业分类
化学 | 564篇 |
晶体学 | 10篇 |
力学 | 5篇 |
数学 | 43篇 |
物理学 | 138篇 |
出版年
2023年 | 6篇 |
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 7篇 |
2019年 | 13篇 |
2018年 | 6篇 |
2016年 | 12篇 |
2015年 | 14篇 |
2014年 | 17篇 |
2013年 | 48篇 |
2012年 | 38篇 |
2011年 | 35篇 |
2010年 | 23篇 |
2009年 | 25篇 |
2008年 | 48篇 |
2007年 | 37篇 |
2006年 | 42篇 |
2005年 | 48篇 |
2004年 | 31篇 |
2003年 | 32篇 |
2002年 | 24篇 |
2001年 | 14篇 |
2000年 | 13篇 |
1999年 | 6篇 |
1998年 | 9篇 |
1996年 | 19篇 |
1995年 | 8篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 10篇 |
1990年 | 5篇 |
1989年 | 5篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 9篇 |
1984年 | 7篇 |
1982年 | 8篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1978年 | 3篇 |
1977年 | 7篇 |
1976年 | 5篇 |
1975年 | 6篇 |
1974年 | 9篇 |
1971年 | 3篇 |
1970年 | 5篇 |
1969年 | 6篇 |
1968年 | 10篇 |
1967年 | 14篇 |
1966年 | 10篇 |
排序方式: 共有760条查询结果,搜索用时 281 毫秒
71.
S. K. Deb?Nath Hironori Tohmyoh M. A. Salam?Akanda 《Applied Physics A: Materials Science & Processing》2011,103(2):493-496
A testing methodology to determine the elastic-plastic properties of thin metallic wires is reported. A small-scaled bending
test of Pt thin wire and the corresponding finite element analysis are performed. By fitting the load-displacement relationship
obtained by finite element analysis to the experimental one, the elastic, elastic-plastic properties of Pt wire are successfully
determined. 相似文献
72.
Thermoelastic damping is recognized as a significant loss mechanism at room temperature in micro-scale circular plate resonators. In this paper, the governing equations of coupled thermoelastic problems are established for axisymmetric out-of-plane vibration of circular plate. Then the analytical expression for thermoelastic damping is obtained. The effects of environmental temperature, plate dimensions and boundary conditions on the thermoelastic damping are studied. 相似文献
73.
Kota Tanaka Saki Okamura Ken Shibata Naoki Ikenaga Nobuyuki Tanaka Kazumi Hakamada Jun Miyake 《Research on Chemical Intermediates》2016,42(11):7723-7730
Renewable energy is regarded as a clean energy source but has some problems, one of which is intermittency. To reduce this, the time-delay of hydrogen production by photosynthetic bacteria can be effective. In this study, we qualitatively evaluated the time-delay of hydrogen production by photosynthetic bacteria under various irradiation conditions, and we also quantitatively evaluated it by fitting the experimental data and the hydrogen production model with a genetic algorithm. As a result of model fitting, we found that the relationship between the lengths of the optimized time-delay of hydrogen production by photosynthetic bacteria and the amount of light irradiation is linear. And we also found that the time-delay of hydrogen production by photosynthetic bacteria had an upper limit under low light intensity. We have suggested the existence of an energy store mechanism in photosynthetic bacteria. 相似文献
74.
75.
76.
Dr. Hironori Onishi 《Mathematische Zeitschrift》1971,120(3):221-223
77.
a one-step conversion of butyne-1,4-diol (1) to 2,3-di(phenylsulfinyl)-1,3-butadiene (4) and the conversion of this bis-sulfoxide to the sulfoxide-sulfone 6 and the bis-sulfone 5 are reported. 相似文献
78.
Gold nanoclusters covered with 4-aminothiophenol (4-ATP) self-assembled monolayers (SAMs) were electrochemically assembled on an Au or ITO electrode. The assembly mechanism is discussed on the basis of results of electrochemical, FT-IR, and XPS measurements. The intensity of plasmon absorption of the gold nanocluster assembly was shown to be dependent on applied potential as a result of electrochemical doping/undoping of a counteranion in the polyaniline film. 相似文献
79.
Ohwada K Fujii Y Katsuki Y Muraoka J Nakao H Murakami Y Sawa H Ninomiya E Isobe M Ueda Y 《Physical review letters》2005,94(10):106401
The present resonant x-ray scattering has been performed on a monoclinically split single domain of NaV(2)O(5). The observation of a critically enhanced contrast between V(4+) and V(5+) ions has led us to the unequivocal conclusion of the charge-order pattern of the low-temperature phase of NaV(2)O(5) below T(c) = 35 K. In spite of the possible four types of configuration of the zigzag-type charge-order patterns in the ab plane (A,A',B and B'), the stacking sequence along the c axis is determined as the AAA'A' type by comparison with model calculations. 相似文献
80.
Sekiguchi K Sakai H Witała H Glöckle W Golak J Hatanaka K Hatano M Itoh K Kamada H Kuboki H Maeda Y Nogga A Okamura H Saito T Sakamoto N Sakemi Y Sasano M Shimizu Y Suda K Tamii A Uesaka T Wakasa T Yako K 《Physical review letters》2005,95(16):162301
Three precise measurements for elastic pd scattering at 135 MeV/A have been performed with the three different experimental setups. The cross sections are described well by the theoretical predictions based on modern nucleon-nucleon forces combined with three-nucleon forces. Relativistic Faddeev calculations show that relativistic effects are restricted to backward angles. This result supports the two measurements recently reported by RIKEN and contradicts the KVI data. 相似文献