全文获取类型
收费全文 | 2532篇 |
免费 | 76篇 |
国内免费 | 7篇 |
专业分类
化学 | 1792篇 |
晶体学 | 16篇 |
力学 | 19篇 |
数学 | 83篇 |
物理学 | 705篇 |
出版年
2023年 | 14篇 |
2021年 | 16篇 |
2020年 | 38篇 |
2019年 | 31篇 |
2018年 | 20篇 |
2017年 | 15篇 |
2016年 | 39篇 |
2015年 | 43篇 |
2014年 | 35篇 |
2013年 | 120篇 |
2012年 | 128篇 |
2011年 | 148篇 |
2010年 | 74篇 |
2009年 | 70篇 |
2008年 | 156篇 |
2007年 | 148篇 |
2006年 | 159篇 |
2005年 | 154篇 |
2004年 | 156篇 |
2003年 | 120篇 |
2002年 | 109篇 |
2001年 | 59篇 |
2000年 | 33篇 |
1999年 | 16篇 |
1998年 | 16篇 |
1997年 | 17篇 |
1996年 | 36篇 |
1995年 | 22篇 |
1994年 | 29篇 |
1993年 | 21篇 |
1992年 | 26篇 |
1991年 | 29篇 |
1990年 | 23篇 |
1989年 | 25篇 |
1988年 | 21篇 |
1987年 | 11篇 |
1986年 | 21篇 |
1985年 | 44篇 |
1984年 | 40篇 |
1983年 | 25篇 |
1982年 | 27篇 |
1981年 | 32篇 |
1980年 | 22篇 |
1979年 | 42篇 |
1978年 | 28篇 |
1977年 | 28篇 |
1976年 | 20篇 |
1975年 | 20篇 |
1974年 | 18篇 |
1973年 | 13篇 |
排序方式: 共有2615条查询结果,搜索用时 15 毫秒
1.
Kobayashi M. Zhang Y. Ishikawa H. Sun J. Oddershede J. Juul Jensen D. Miura H. 《Experimental Mechanics》2021,61(5):817-828
Experimental Mechanics - The internal strain distribution developing during plastic deformation is important for understanding the mechanical properties of polycrystalline materials. Such... 相似文献
2.
Amano Yuki Ishikawa Satoshi Yoshitake Tatsuhiro Kondou Takahiro 《Nonlinear dynamics》2021,104(3):1917-1935
Nonlinear Dynamics - Rectangular flat-bottom liquid tanks known as tuned liquid dampers (TLDs) are often used as passive mechanical dampers. Sloped- and triangular-bottom TLDs have been reported to... 相似文献
3.
Susumu Onaka 《哲学杂志》2020,100(13):1703-1715
4.
Prof. Isao Fujii Dr. Makoto Hashimoto Kaori Konishi Akiko Unezawa Haruka Sakuraba Kenta Suzuki Harue Tsushima Miho Iwasaki Satsuki Yoshida Akane Kudo Rina Fujita Aika Hichiwa Koharu Saito Dr. Takashi Asano Dr. Jun Ishikawa Dr. Daigo Wakana Dr. Yukihiro Goda Ayumi Watanabe Mamoru Watanabe Yui Masumoto Dr. Junichiro Kanazawa Dr. Hajime Sato Prof. Masanobu Uchiyama 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(22):8542-8548
Shimalactones A and B are neuritogenic polyketides possessing characteristic oxabicyclo[2.2.1]heptane and bicyclo[4.2.0]octadiene ring systems that are produced by the marine fungus Emericella variecolor GF10. We identified a candidate biosynthetic gene cluster and conducted heterologous expression analysis. Expression of ShmA polyketide synthase in Aspergillus oryzae resulted in the production of preshimalactone. Aspergillus oryzae and Saccharomyces cerevisiae transformants expressing ShmA and ShmB produced shimalactones A and B, thus suggesting that the double bicyclo-ring formation reactions proceed non-enzymatically from preshimalactone epoxide. DFT calculations strongly support the idea that oxabicyclo-ring formation and 8π-6π electrocyclization proceed spontaneously after opening of the preshimalactone epoxide ring through protonation. We confirmed the formation of preshimalactone epoxide in vitro, followed by its non-enzymatic conversion to shimalactones in the dark. 相似文献
5.
6.
7.
Motohiro Suzuki Yuichi Inubushi Makina Yabashi Tetsuya Ishikawa 《Journal of synchrotron radiation》2014,21(3):466-472
A diamond phase retarder was applied to control the polarization states of a hard X‐ray free‐electron laser (XFEL) in the photon energy range 5–20 keV. The horizontal polarization of the XFEL beam generated from the planar undulators of the SPring‐8 Angstrom Compact Free‐Electron Laser (SACLA) was converted into vertical or circular polarization of either helicity by adjusting the angular offset of the diamond crystal from the exact Bragg condition. Using a 1.5 mm‐thick crystal, a high degree of circular polarization, 97%, was obtained for 11.56 keV monochromatic X‐rays, whereas the degree of vertical polarization was 67%, both of which agreed with the estimations including the energy bandwidth of the Si 111 beamline monochromator. 相似文献
8.
9.
Dr. Jiawei Zhang Dr. Daisuke Ishikawa Dr. Michael M. Koza Prof. Dr. Eiji Nishibori Dr. Lirong Song Dr. Alfred Q. R. Baron Prof. Dr. Bo B. Iversen 《Angewandte Chemie (International ed. in English)》2023,62(13):e202218458
Loosely bonded (“rattling”) atoms with s2 lone pair electrons are usually associated with strong anharmonicity and unexpectedly low thermal conductivity, yet their detailed correlation remains largely unknown. Here we resolve this correlation in thermoelectric InTe by combining chemical bonding analysis, inelastic X-ray and neutron scattering, and first principles phonon calculations. We successfully probe soft low-lying transverse phonons dominated by large In1+ z-axis motions, and their giant anharmonicity. We show that the highly anharmonic phonons arise from the dynamic lone pair expression with unstable occupied antibonding states induced by the covalency between delocalized In1+ 5s2 lone pair electrons and Te 5p states. This work pinpoints the microscopic origin of strong anharmonicity driven by rattling atoms with stereochemical lone pair activity, important for designing efficient materials for thermoelectric energy conversion. 相似文献
10.
Dr. Ziqian Xue Dr. Jia-Jia Zheng Dr. Yusuke Nishiyama Dr. Ming-Shui Yao Dr. Yoshitaka Aoyama Zeyu Fan Dr. Ping Wang Prof. Takashi Kajiwara Prof. Yoshiki Kubota Prof. Satoshi Horike Prof. Ken-ichi Otake Prof. Susumu Kitagawa 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(2):e202215234
Exploring new porous coordination polymers (PCPs) that have tunable structure and conductivity is attractive but remains challenging. Herein, fine pore structure engineering by ligand conformation control of naphthalene diimide (NDI)-based semiconducting PCPs with π stacking-dependent conductivity tunability is achieved. The π stacking distances and ligand conformation in these isoreticular PCPs were modulated by employing metal centers with different coordination geometries. As a result, three conjugated PCPs (Co−pyNDI, Ni−pyNDI, and Zn−pyNDI) with varying pore structure and conductivity were obtained. Their crystal structures were determined by three-dimensional electron diffraction. The through-space charge transfer and tunable pore structure in these PCPs result in modulated selectivity and sensitivity in gas sensing. Zn−pyNDI can serve as a room-temperature operable chemiresistive sensor selective to acetone. 相似文献