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排序方式: 共有8908条查询结果,搜索用时 15 毫秒
981.
982.
Organic Electronics: Spatial Mapping of Morphology and Electronic Properties of Air‐Printed Pentacene Thin Films (Adv. Funct. Mater. 25/2014)
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983.
Superparamagnetic Twist‐Type Actuators with Shape‐Independent Magnetic Properties and Surface Functionalization for Advanced Biomedical Applications
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Christian Peters Olgaç Ergeneman Pedro D. Wendel García Michelle Müller Salvador Pané Bradley J. Nelson Christofer Hierold 《Advanced functional materials》2014,24(33):5269-5276
Directed nanoparticle self‐organization and two‐photon polymerization are combined to enable three‐dimensional soft‐magnetic microactuators with complex shapes and shape‐independent magnetic properties. Based on the proposed approach, single and double twist‐type swimming microrobots with programmed magnetic anisotropy are demonstrated, and their swimming properties in DI‐water are characterized. The fabricated devices are actuated using weak rotating magnetic fields and are capable of performing wobble‐free corkscrew propulsion. Single twist‐type actuators possess an increase in surface area in excess of 150% over helical actuators with similar feature size without compromising the forward velocity of over one body length per second. A generic and facile combination of glycine grafting and subsequent protein immobilization exploits the actuator's increased surface area, providing for a swimming microrobotic platform with enhanced load capacity desirable for future biomedical applications. Successful surface modification is confirmed by FITC fluorescence. 相似文献
984.
985.
Thorsten Falk Ralf Heese Christian Kaspar Malgorzata Mochol Daniel Pfeiffer Michael Thygs Robert Tolksdorf 《Informatik-Spektrum》2006,29(3):201-209
Zusammenfassung The importance of the Internet for job procurement is increasing for the reason that three quarters of the people in the employment age are online. On the other hand because ever more companies are publishing their job offers on the Web. However, due to the large number of openings published online it is almost impossible for job seekers and job portals to gain an overview of the entire employment market. Since job offers lack semantically meaningful annotations, the search and integration into databases are made highly difficult. Applying Semantic Web technologies to the e-recruitment process provides advantages for all participants in the market. In this paper we describe a method for analysing the domain-specific language of an application domain. We use this method to describe the e-recruitment process and the necessary ontologies for annotating job offers and job applications. In conclusion, we present the prototypical implementation of the scenario based on Semantic Web, especially semantic matching. 相似文献
986.
Ulrich Glaser Kai Esmark Martin Streibl Christian Russ Krzysztof Domaski Mauro Ciappa Wolfgang Fichtner 《Microelectronics Reliability》2007,47(7):1044-1053
Diodes and diode strings in 90 nm and beyond technologies are investigated by measurement and device simulation. After a thorough calibration, the device simulator is utilised to achieve a better understanding and an enhanced device performance of diode strings under static and transient ESD conditions. Thereto, parasitic transistors and a so far neglected parasitic thyristor (SCR) in the diode string are regarded, exploited and optimised. 相似文献
987.
Carbon dioxide intensities in economic terms (GDP in PPP terms) in industrialized and developing countries have been shown to converge, and it has been argued that technology diffusion, leading to the use of similar technologies in all countries, is an important reason for this convergence. Indicators based on CO2 per output in PPP terms, however, give in comparison to physical indicators limited understanding of the process of technology diffusion. In order to analyze the technology diffusion hypothesis in more detail, we therefore study the trend in carbon dioxide emissions in relation to the production output in four separate sectors: iron and steel; paper, board and pulp; coal fuelled power plants; and natural gas fuelled power plants, in each of 12 countries, between 1980 and 1998. The indicators converge in each sector, indicating that across countries, technologies with more similar carbon dioxide efficiencies are used today than 25 years ago. We also find that at least some developing countries with high energy prices use more efficient technologies than industrialized countries with low energy prices. 相似文献
988.
Summary. A complete communication system is broken down into a number of protocol layers each of which provides services to the layer
above it and uses services provided by its underlying layer. A service specification defines a particular ordering of the
operations that a given layer provides to the layer above it. The active elements in each layer are called entities and they
use a protocol in order to implement their service definition. On the basis of this relation between the service and protocol
concepts we have developed algorithms for deriving protocol entity specifications from a formal service specification. The
derived protocol entities ensure the correct ordering of the service primitives by exchanging synchronization messages through
an underlying communication medium. This paper presents an extended version of our earlier derivation algorithms. This version
of the algorithm can handle all operators and unrestricted process invocation and recursion as defined by basis LOTOS. The
correctness of this derivation algorithm is formally proved.
Received: January 1992 / Accepted: February 1996 相似文献
989.
990.
Um kontaminiertes Grubenwasser langfristig kostengünstig reinigen zu k?nnen, sind Methoden mit geringstm?glichen Investitions-
und Unterhaltungskosten n?tig. Dazu wurden in Gro?britannien und Deutschland in den zurückliegenden Jahren unterschiedliche
passive Reinigungssysteme in Betrieb genommen (z. B. anoxische Karbonatkan?le, konstruierte Feuchtgebiete, reaktive Barrieren,
Gro?oberfl?chenfilter). 相似文献