全文获取类型
收费全文 | 1248篇 |
免费 | 103篇 |
国内免费 | 4篇 |
专业分类
化学 | 1082篇 |
晶体学 | 15篇 |
力学 | 27篇 |
数学 | 53篇 |
物理学 | 178篇 |
出版年
2023年 | 16篇 |
2022年 | 21篇 |
2021年 | 27篇 |
2020年 | 31篇 |
2019年 | 26篇 |
2018年 | 35篇 |
2017年 | 20篇 |
2016年 | 54篇 |
2015年 | 44篇 |
2014年 | 68篇 |
2013年 | 74篇 |
2012年 | 110篇 |
2011年 | 150篇 |
2010年 | 71篇 |
2009年 | 66篇 |
2008年 | 96篇 |
2007年 | 72篇 |
2006年 | 73篇 |
2005年 | 55篇 |
2004年 | 55篇 |
2003年 | 46篇 |
2002年 | 32篇 |
2001年 | 14篇 |
2000年 | 11篇 |
1999年 | 6篇 |
1998年 | 8篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 6篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 6篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1980年 | 2篇 |
1978年 | 3篇 |
1973年 | 1篇 |
1969年 | 1篇 |
1931年 | 1篇 |
排序方式: 共有1355条查询结果,搜索用时 635 毫秒
71.
Masahiro Terashima Takuya Miyayama Tetsuro Shirao Hin Wai Mo Yasuhiro Hatae Hiroshi Fujimoto Katsumi Watanabe 《Surface and interface analysis : SIA》2020,52(12):948-952
Low-energy inverse photoelectron spectroscopy (LEIPS) and ultraviolet photoelectron spectroscopy (UPS) incorporated into the multitechnique XPS system were used to probe the ionization potential and the electron affinity of organic materials, respectively. By utilizing gas cluster ion beam (GCIB), in situ analyses and depth profiling of LEIPS and UPS were also demonstrated. The band structures of the 10-nm-thick buckminsterfullerene (C60) thin film on Au (100 nm)/indium tin oxide (100 nm)/glass substrate were successfully evaluated in depth direction. 相似文献
72.
Syota Shimizu Akihiro Aoki Takuya Takahashi Fumiki Harano 《Photochemistry and photobiology》2020,96(5):1105-1115
Infrared-A (IRA), which can penetrate deeply into the human skin, is a major component of solar radiation and is recognized to promote photoaging of human dermis. To our knowledge, however, the cellular and molecular consequences of human epidermis exposure to IRA have not been clarified. Thus, we investigated whether IRA inhibits the proliferation of normal human epidermal keratinocytes (NHEKs). IRA irradiation ed in cell cycle arrest at G1 and a dose-dependent reduction in the proliferation of NHEKs. We found that mechanistic target of rapamycin complex 1 (mTORC1) was initially inactivated during IRA irradiation due to the formation of stress granules (SGs), and this inactivation was maintained for at least 6 h after irradiation due to Akt dephosphorylation. Furthermore, repeated exposure of human skin equivalents to IRA led to marked thinning of the epidermal cell layer. In conclusion, IRA irradiation inhibits mTORC1 activity possibly through two molecular mechanisms involving SG formation in the early-phase and subsequent Akt dephosphorylation. This sequential mechanism seems to cause G1 cell cycle arrest and a reduction in cell proliferation, supporting the hypothesis that the decreased proliferation of basal keratinocytes that occurs during skin aging might be partly attributable to IRA radiation. 相似文献
73.
Dr. Zhen Jiang Ming Li Tan Mahdiar Taheri Dr. Qiao Yan Prof. Takuya Tsuzuki Dr. Michael G. Gardiner Broden Diggle Prof. Luke A. Connal 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(18):7115-7122
The most pressing challenges for light-driven hydrogel actuators include reliance on UV light, slow response, poor mechanical properties, and limited functionalities. Now, a supramolecular design strategy is used to address these issues. Key is the use of a benzylimine-functionalized anthracene group, which red-shifts the absorption into the visible region and also stabilizes the supramolecular network through π–π interactions. Acid–ether hydrogen bonds are incorporated for energy dissipation under mechanical deformation and maintaining hydrophilicity of the network. This double-crosslinked supramolecular hydrogel developed via a simple synthesis exhibits a unique combination of high strength, rapid self-healing, and fast visible-light-driven shape morphing both in the wet and dry state. As all of the interactions are dynamic, the design enables the structures to be recycled and reprogrammed into different 3D objects. 相似文献
74.
Journal of Computer-Aided Molecular Design - In this study, a new method is proposed for calculating the relative binding free energy between a ligand and a protein, derived from a free energy... 相似文献
75.
Ryo Kimura Hikaru Kuramochi Pengpeng Liu Takuya Yamakado Atsuhiro Osuka Tahei Tahara Shohei Saito 《Angewandte Chemie (International ed. in English)》2020,59(38):16430-16435
Flapping fluorophores (FLAP) with a flexible 8π ring are rapidly gaining attention as a versatile photofunctional system. Here we report a highly photostable “flapping peryleneimide” with an unprecedented fluorogenic mechanism based on a bent‐to‐planar conformational change in the S1 excited state. The S1 planarization induces an electronic configurational switch, almost quenching the inherent fluorescence (FL) of the peryleneimide moieties. However, the FL quantum yield is remarkably improved with a prolonged lifetime upon a slight environmental change. This fluorogenic function is realized by sensitive π‐conjugation design, as a more π‐expanded analogue does not show the planarization dynamics. With strong visible‐light absorption, the FL lifetime response synchronized with the flexible flapping motion is useful for the latest optical techniques such as FL lifetime imaging microscopy (FLIM). 相似文献
76.
Taishin Takamura Takuya Harada Tatsuro Furuta Takao Ikariya Shigeki Kuwata 《化学:亚洲杂志》2020,15(1):72-78
Synthesis and deprotonation reactions of half‐sandwich iridium complexes bearing a vicinal dioxime ligand were studied. Treatment of [{Cp*IrCl(μ‐Cl)}2] (Cp*=η5‐C5Me5) with dimethylglyoxime (LH2) at an Ir:LH2 ratio of 1:1 afforded the cationic dioxime iridium complex [Cp*IrCl(LH2)]Cl ( 1 ). The chlorido complex 1 undergoes stepwise and reversible deprotonation with potassium carbonate to give the oxime–oximato complex [Cp*IrCl(LH)] ( 2 ) and the anionic dioximato(2?) complex K[Cp*IrCl(L)] ( 3 ) sequentially. Meanwhile, twofold deprotonation of the sulfato complex [Cp*Ir(SO4)(LH2)] ( 4 ) resulted in the formation of the oximato‐bridged dinuclear complex [{Cp*Ir(μ‐L)}2] ( 5 ). X‐ray analyses disclosed their supramolecular structures with one‐dimensional infinite chain ( 1 and 2 ), hexagonal open channels ( 3 ), and a tetrameric rhomboid ( 4 ) featuring multiple intermolecular hydrogen bonds and electrostatic interactions. 相似文献
77.
Kazuchika Ohta Satoru Azumane Takuya Watanabe Satoshi Tsukada Iwao Yamamoto 《应用有机金属化学》1996,10(8):623-635
Eight novel octakis(3,4-dialkoxyphenyl)- phthalocyanine derivatives, Cn-M (2, M=2H; 3, M=Ni; 4, M=Cu; a, decyloxy; b, undecyloxy; c, dodecyloxy), have been synthesized and characterized. It was found that each of the derivatives exhibits discotic liquid crystalline properties, and that each of the Cn–Cu (4) derivatives has two kinds of Drd2( P 21/ a ) mesophases. These Cn–Cu (4a,b,c) and C12–2H (2c) derivatives exhibit a unique double clearing behavior. 相似文献
78.
79.
Shahi Imam Reja Yuichiro Hori Takuya Kamikawa Kohei Yamasaki Miyako Nishiura Steven D. Bull Kazuya Kikuchi 《Chemical science》2022,13(5):1419
The ability to monitor proteolytic pathways that remove unwanted and damaged proteins from cells is essential for understanding the multiple processes used to maintain cellular homeostasis. In this study, we have developed a new protein-labeling probe that employs an ‘OFF–ON–OFF’ fluorescence switch to enable real-time imaging of the expression (fluorescence ON) and degradation (fluorescence OFF) of PYP-tagged protein constructs in living cells. Fluorescence switching is modulated by intramolecular contact quenching interactions in the unbound probe (fluorescence OFF) being disrupted upon binding to the PYP-tag protein, which turns fluorescence ON. Quenching is then restored when the PYP-tag–probe complex undergoes proteolytic degradation, which results in fluorescence being turned OFF. Optimization of probe structures and PYP-tag mutants has enabled this fast reacting ‘OFF–ON–OFF’ probe to be used to fluorescently image the expression and degradation of short-lived proteins.An “OFF–ON–OFF” fluorescence probe for real-time imaging of the expression (fluorescence ‘OFF’) and degradation (fluorescence ‘ON’) of short lived PYP-tag proteins in cellular systems. 相似文献
80.
Takuya Hosokawa Keiji Izuchi Shûichi Ohno 《Integral Equations and Operator Theory》2005,53(4):509-526
We study properties of the topological space of weighted composition operators on the space of bounded analytic functions
on the open unit disk in the uniform operator topology. Moreover, we characterize the compactness of differences of two weighted
composition operators. 相似文献