全文获取类型
收费全文 | 1069篇 |
免费 | 94篇 |
国内免费 | 5篇 |
专业分类
化学 | 845篇 |
晶体学 | 3篇 |
力学 | 19篇 |
数学 | 129篇 |
物理学 | 172篇 |
出版年
2023年 | 29篇 |
2022年 | 20篇 |
2021年 | 44篇 |
2020年 | 63篇 |
2019年 | 54篇 |
2018年 | 22篇 |
2017年 | 30篇 |
2016年 | 52篇 |
2015年 | 61篇 |
2014年 | 45篇 |
2013年 | 56篇 |
2012年 | 66篇 |
2011年 | 80篇 |
2010年 | 38篇 |
2009年 | 43篇 |
2008年 | 45篇 |
2007年 | 41篇 |
2006年 | 48篇 |
2005年 | 26篇 |
2004年 | 17篇 |
2003年 | 19篇 |
2002年 | 19篇 |
2001年 | 13篇 |
2000年 | 12篇 |
1999年 | 11篇 |
1998年 | 13篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1993年 | 8篇 |
1992年 | 5篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 13篇 |
1988年 | 10篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1985年 | 8篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 10篇 |
1981年 | 7篇 |
1980年 | 8篇 |
1979年 | 4篇 |
1977年 | 15篇 |
1976年 | 8篇 |
1975年 | 11篇 |
1974年 | 6篇 |
1973年 | 9篇 |
1937年 | 5篇 |
排序方式: 共有1168条查询结果,搜索用时 125 毫秒
961.
962.
Dr. Niels Zijlstra Fabian Dingfelder Dr. Bengt Wunderlich Dr. Franziska Zosel Dr. Stephan Benke Dr. Daniel Nettels Prof. Dr. Benjamin Schuler 《Angewandte Chemie (International ed. in English)》2017,56(25):7126-7129
To enable the investigation of low-affinity biomolecular complexes with confocal single-molecule spectroscopy, we have developed a microfluidic device that allows a concentrated sample to be diluted by up to five orders of magnitude within milliseconds, at the physical limit dictated by diffusion. We demonstrate the capabilities of the device by studying the dissociation kinetics and structural properties of low-affinity protein complexes using single-molecule two-color and three-color Förster resonance energy transfer (FRET). We show that the versatility of the device makes it suitable for studying complexes with dissociation constants from low nanomolar up to 10 μm , thus covering a wide range of biomolecular interactions. The design and precise fabrication of the devices ensure simple yet reliable operation and high reproducibility of the results. 相似文献
963.
964.
965.
966.
A key feature of dynamic problems which offer degrees of freedom to the decision maker is the necessity for a goal-oriented decision making routine which is employed every time the logic of the system requires a decision. In this paper, we look at optimization procedures which appear as subroutines in dynamic problems and show how discrete event simulation can be used to assess the quality of algorithms: after establishing a general link between online optimization and discrete event systems, we address performance measurement in dynamic settings and derive a corresponding tool kit. We then analyze several control strategies using the methodologies discussed previously in two real world examples of discrete event simulation models: a manual order picking system and a pickup and delivery service. 相似文献
967.
A rapid and efficient protocol assisted by microwave irradiation for the synthesis of esters using methanesulfonic acid (CH3SO3H) supported on Al2O3 (AMA) as catalyst and free of solvent is described. The products were obtained in good yields and purity, with reduced reaction time, and the process is simple and environmentally benign. 相似文献
968.
Ugochi K. Chime Agnes C. Nkele Sabastine Ezugwu Assumpta C. Nwanya N.M. Shinde Mesfin Kebede Paul M. Ejikeme M. Maaza Fabian I. Ezema 《Current Opinion in Electrochemistry》2020
In recent years, interest in nanostructured electrode materials for use in supercapacitors has been on the rise. Nickel oxide has been reported as a good candidate for supercapacitor applications due to its high theoretical capacitance and low cost. However, its poor electrical conductivity has resulted in actual poor specific capacitance and cycling ability. Over the years, researchers have studied various techniques to modify the structure and composition of NiO with the aim of improving its electrochemical performance. In this review, we opine that NiO-based electrodes can be fabricated using different approaches and different composite forms in order to obtain cells of high efficiency and specific capacitances. We discuss the recent advances in NiO-based electrodes fabricated using different approaches. 相似文献
969.
970.