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排序方式: 共有1350条查询结果,搜索用时 15 毫秒
81.
Christian Müller Liangqi Ouyang Anja Lund Kasper Moth‐Poulsen Mahiar M. Hamedi 《Advanced materials (Deerfield Beach, Fla.)》2019,31(22)
Organic semiconductors are the centerpiece of several vibrant research fields from single‐molecule to organic electronics, and they are finding increasing use in bioelectronics and even classical polymer technology. The versatile chemistry and broad range of electronic functionalities of conjugated materials enable the bridging of length scales 15 orders of magnitude apart, ranging from a single nanometer (10?9 m) to the size of continents (106 m). This work provides a taste of the diverse applications that can be realized with organic semiconductors. The reader will embark on a journey from single molecular junctions to thin film organic electronics, supramolecular assemblies, biomaterials such as amyloid fibrils and nanofibrillated cellulose, conducting fibers and yarns for e‐textiles, and finally to power cables that shuffle power across thousands of kilometers. 相似文献
82.
Dirkzwager Anja J. E.; Bramsen Inge; Adèr Herman; van der Ploeg Henk M. 《Canadian Metallurgical Quarterly》2005,19(2):217
This study examines secondary traumatization among 708 partners and 332 parents of Dutch peacekeepers (i.e., personnel who participated in military actions implemented by international organizations such as the United Nations). Partners or parents of peacekeepers with 4 levels of posttraumatic stress symptoms were compared on posttraumatic stress, health problems, the quality of the marital relationship, and social support. In comparison with partners of peacekeepers without posttraumatic stress disorder (PTSD) symptoms, partners of peacekeepers with PTSD symptoms reported more sleeping and somatic problems, reported more negative social support, and judged the marital relationship as less favorable. No significant differences were found for parents. Thus, peacekeepers' stress reactions were related to various problems of their partners. A systemic approach to the treatment of persons with PTSD appears appropriate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
83.
This paper presents recent experimental investigations on the influence of loading rate on the fracture toughness KIc for different structural steels. The loading rate in terms of increasing in stress intensity factor was changed from quasistatic up to dynamic conditions (
). The results show significant differences in the amount of temperature shift between KIc -T curve obtained after static and dynamic loading for the materials investigated. Based on microscopic fracture criteria for cleavage fracture correlations were made between fracture toughness and yielding behaviour depending on temperature and strain rate. The experimental results were also compared with the predictions given by different models. The most promising results were achieved by a correlation between transition temperature shift in KIc caused by dynamic loading and strain rate sensitivity
of steels. 相似文献
Full-size image (<1K)
84.
85.
Suzanne Liebowitz Taylor Deborah A. Dahl Mark Lipshutz Carl Weir Lewis M. Norton Roslyn Weidner Nilson Marcia C. Linebarger 《Artificial Intelligence Review》1994,8(2-3):255-276
Document understanding, the interpretation of a document from its image form, is a technology area which benefits greatly from the integration of natural language processing with image processing. We have developed a prototype of an Intelligent Document Understanding System (IDUS) which employs several technologies: image processing, optical character recognition, document structure analysis and text understanding in a cooperative fashion. This paper discusses those areas of research during development of IDUS where we have found the most benefit from the integration of natural language processing and image processing: document structure analysis, optical character recognition (OCR) correction, and text analysis. We also discuss two applications which are supported by IDUS: text retrieval and automatic generation of hypertext links 相似文献
86.
87.
Nicole Altvater-Mackensen Gregor Balicki Lucie Bestakowa Bianca Bocatius Johannes Braun Lars Brehmer Verena Brune Kirstina Eigemeier F&#;sun Erdem Ralf Fritscher Anne Jacobs Bernd Klingsporn Marcin Kosinski Julia Kuntze Ju-Ra Lee Anna Osterhage Martin Probost Thorsten Risch Tobias Schmitt Wolfgang G. Stock Anja Sturm Katrin Weller Kerstin Werner 《Scientometrics》2005,63(3):463-529
Summary We operationalize scientific output in a region by means of the number of articles (as in the SciSearch database) per year and technology output by means of the number of patent applications (as in the database of the European Patent Office) per priority year. All informetric analyses were done using the DIALOG online-system. The main research questions are the following: Which scientific and technological fields or topics are most influent within a region and which institutions or companies are mainly publishing articles or holding patents? Do the distributions of regional science and technology fields and of publishing institutions follow the well-known informetric function? Are there - as it is expected - only few fields and few institutions which dominate the region? Is there a connection between the economic power of a region and the regional publication and patent output? Examples studied in detail are seven German regions: Aachen, Düsseldorf, Hamburg, Köln (Cologne), Leipzig - Halle - Dessau, München (Munich), and Stuttgart. Three different indicators were used, science and technology attraction of a region (number of scientific articles and patents), science and technology intensity (articles and patents per 1,000 inhabitants), and science and technology density (articles and patents per 1 billion EURO gross value added). Top region concerning both attraction and intensity is Munich, concerning density it is Aachen. 相似文献
88.
89.
Damián Alvarez Paggi Anja Kranich Marcelo A. Martí Daniel H. Murgida 《Electrochimica acta》2009,54(22):4963-18098
In this paper we present a combined experimental and theoretical study of the heterogeneous electron transfer reaction of cytochrome c electrostatically adsorbed on metal electrodes coated with monolayers of 6-mercaptohexanoic acid. Molecular dynamics simulations and pathways calculations show that adsorption of the protein leads to a broad distribution of orientations and, thus, to a correspondingly broad distribution of electron transfer rate constants due to the orientation-dependence of the electronic coupling parameter. The adsorbed protein exhibits significant mobility and, therefore, the measured reaction rate is predicted to be a convolution of protein dynamics and tunnelling probabilities for each orientation. This prediction is confirmed by time-resolved surface enhanced resonance Raman which allows for the direct monitoring of protein (re-)orientation and electron transfer of the immobilised cytochrome c. The results provide a consistent explanation for the non-exponential distance-independence of electron transfer rates usually observed for proteins immobilized on electrodes. 相似文献
90.
A. Halim D. Dormagen H. Dünnewald-Arfmann M. Twickler R. Twickler W. Dahl 《Nuclear Engineering and Design》1987,105(1)
As cleavage fracture follows a tensile stress criterion, it is possible to predict fracture toughness KIc as a function of temperature when small scale yielding stress distribution in combination with the Ritchie, Knott and Rice criterion is used. With increasing temperature and thus pronounced plasticity the crack tip blunts and the experimental values are underestimated. The Schmidtmann and Nierhoff proposal for modifying the cleavage stress criterion and introducing the effect of crack tip blunting is compared with the RKR-model and with experimentally determined KIc-values for four different qualities of Fe 510 steels. The steels mainly differ in sulphur content and sulphur shape control. Thus the effect of sulphur on cleavage fracture will be discussed. 相似文献