全文获取类型
收费全文 | 990篇 |
免费 | 87篇 |
国内免费 | 5篇 |
专业分类
化学 | 740篇 |
晶体学 | 1篇 |
力学 | 13篇 |
数学 | 189篇 |
物理学 | 139篇 |
出版年
2024年 | 2篇 |
2023年 | 22篇 |
2022年 | 28篇 |
2021年 | 45篇 |
2020年 | 60篇 |
2019年 | 64篇 |
2018年 | 20篇 |
2017年 | 22篇 |
2016年 | 56篇 |
2015年 | 58篇 |
2014年 | 44篇 |
2013年 | 57篇 |
2012年 | 71篇 |
2011年 | 81篇 |
2010年 | 53篇 |
2009年 | 65篇 |
2008年 | 62篇 |
2007年 | 54篇 |
2006年 | 42篇 |
2005年 | 37篇 |
2004年 | 26篇 |
2003年 | 21篇 |
2002年 | 15篇 |
2001年 | 7篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 5篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 7篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1982年 | 1篇 |
1980年 | 3篇 |
1974年 | 1篇 |
排序方式: 共有1082条查询结果,搜索用时 203 毫秒
21.
22.
Dr. Melanie Koehler Dr. Dominik Farka Dr. Cigdem Yumusak Prof. Dr. Niyazi Serdar Sariciftci Prof. Dr. Peter Hinterdorfer 《Chemphyschem》2020,21(7):659-666
Hydrogen-bonded organic semiconductors are extraordinarily stable organic solids forming stable, large crystallites with the ability to preserve favorable electrical properties upon bioconjugation. Lately, tremendous efforts have been made to use these bioconjugated semiconductors as platforms for stable multifunctional bioelectronics devices, yet the detailed characterization of bio-active binding sites (orientation, density, etc.) at the nanoscale has not been achieved yet. The presented work investigates the bioconjugation of epindolidione and quinacridone, two representative semiconductors, with respect to their exposed amine-functionalities. Relying on the biotin-avidin lock-and-key system and applying the atomic force microscopy (AFM) derivative topography and recognition (TREC) imaging, we used activated biotin to flag crystal-faces with exposed amine functional groups. Contrary to previous studies, biotin bonds were found to be stable towards removal by autolysis. The resolution strength and clear recognition capability makes TREC-AFM a valuable tool in the investigation of bio-conjugated, hydrogen-bonded semiconductors. 相似文献
23.
24.
Yukun Cheng Xiaotie Deng Dominik Scheder 《4OR: A Quarterly Journal of Operations Research》2018,16(3):231-260
Market makers choose and design market rules to serve certain objectives, such as to maximize revenue from the sales in the case of a single seller and multiple buyers. Given such rules, market participants play against each other to maximize their utility function values on goods acquired, possibly by hiding or misrepresenting their information needed in the implementation of market rules. Today’s Internet economy has changed the information collection process and may make some of the assumptions of market rule implementation obsolete. Here we make a fresh review of works on this challenge on the Internet where new economic systems operate. 相似文献
25.
Dominik Lungerich Jakob F. Hitzenberger Wolfgang Donaubauer Prof. Thomas Drewello Prof. Norbert Jux 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):16755-16759
A feasible two‐step synthesis and characterization of a full series of hexaarylbenzene (HAB) substituted porphyrins and tetrabenzoporphyrins is presented. Key steps represent the microwave‐assisted porphyrin condensation and the statistical Diels–Alder reaction to the desired HAB‐porphyrins. Regarding their applications, they proved to be easily accessible and effective high molecular mass calibrants for (MA)LDI mass spectrometry. The free‐base and zinc(II) porphyrin systems, as well as the respective tetrabenzoporphyrins, demonstrate in solid state experiments strong red‐ and near‐infrared‐light emission and are potentially interesting for the application in “truly organic” light‐emitting devices. Lastly, they represent facile precursors to large polycyclic aromatic hydrocarbon (PAH) substituted porphyrins. We prepared the first tetra‐hexa‐peri‐hexabenzocoronene substituted porphyrin, which represents the largest prepared PAH‐porphyrin conjugate to date. 相似文献
26.
Robert Cichon Dominik Raab Simon Hewera Andrea Lazik-Palm Jens Theysohn Stefan Landgraeber Wojciech Kowalczyk 《PAMM》2016,16(1):77-78
In recent years, femoroacetabular impingement (FAI) has become increasingly common. As published in the literature, FAI is caused by an unphysiological contact between the proximal femur and the acetabular rim, which may lead to pain, limitation of movement, and damage of cartilage. In this paper, patient-specific finite element simulations of the movement of the hip based on gait motion data and MRI segmentation were conducted to check stresses of the acetabulum and femur, and additionally whether a bony contact is present or not. The study's findings show no bony contact between femur and acetabulum, which may lead to the hypothesis that the labrum and its deformation and/or the articular capsule are involved in the mechanism of FAI. In order to verify this hypothesis more simulations including labrum and capsule must be performed. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
27.
Adrian Adamski Andrzej Biadasz Krzysztof Domieracki Marek Andrzej Kojdecki Dominik Paukszta Dominika Uryzaj 《Liquid crystals》2013,40(4):456-462
Liquid-crystalline perylene-3,4,9,10-tetra-(n-hexylester) forms characteristic dendritic or flower-like structures at room temperature when it is deposited on a hydrophilic glass substrate using the zone-casting technique. It was found that such unique structures were not possible to be created simply by recrystallisation of this dye from a liquid-crystalline columnar phase. On the basis of the observations using a confocal microscope and the study of wide angle X-ray scattering (WAXS) as well as the analysis of the absorption and fluorescence spectra, some conclusions, concerning the molecular organisation in the dendritic structure, are drawn. Based on the research, one can assume that the dendrites are formed by columnar molecular aggregates with the column axes parallel to the substrate. Such an organisation of the molecules can be interesting from the point of view of organic electronics. 相似文献
28.
Prof. Dr. Sjoerd Harder Dominik Naglav Dr. Christian Ruspic Prof. Dr. Claudia Wickleder Dr. Matthias Adlung Dr. Wilfried Hermes Dr. Matthias Eul Prof. Dr. Rainer Pöttgen Dr. Daniel B. Rego Prof. Dr. Frederic Poineau Prof. Dr. Kenneth R. Czerwinski Prof. Dr. Rolfe H. Herber Prof. Dr. Israel Nowik 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(37):12173-12173
29.
30.
Peter Fechner Oliver Bleher Melanie Ewald Kathrin Freudenberger Dominik Furin Urs Hilbig Felix Kolarov Katrin Krieg Lothar Leidner Goran Markovic Günther Proll Florian Pröll Sabrina Rau Johannes Riedt Barbara Schwarz Patricia Weber Julia Widmaier 《Analytical and bioanalytical chemistry》2014,406(17):4033-4051
This review is focused on methods for detecting small molecules and, in particular, the characterisation of their interaction with natural proteins (e.g. receptors, ion channels). Because there are intrinsic advantages to using label-free methods over labelled methods (e.g. fluorescence, radioactivity), this review only covers label-free techniques. We briefly discuss available techniques and their advantages and disadvantages, especially as related to investigating the interaction between small molecules and proteins. The reviewed techniques include well-known and widely used standard analytical methods (e.g. HPLC-MS, NMR, calorimetry, and X-ray diffraction), newer and more specialised analytical methods (e.g. biosensors), biological systems (e.g. cell lines and animal models), and in-silico approaches. 相似文献