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排序方式: 共有4183条查询结果,搜索用时 15 毫秒
121.
Hahn Griebel W. Schreiber Carls J. Großfeld Steinbeck Beckel Schwaibold Lehnartz Meumann Schormüller Jesser R. Strohecker Lehnartz Diemair R. Grau Lars Erlandson Patzsch Reichard Ph. Bruno Roßmann Brüning Karl Sauer Willy Lindner Kanitz O. Windhausen Schloemer Amelung M. Steiner R. Mancke K. Höll Goreczky E. Tornow Zacher Kleinhans Bäurle 《European Food Research and Technology》1943,85(1):70-112
122.
Karl Sauer Diemair E. Dinslage Kanitz Schwaibold Willy Lindner Haevecker Lehnartz E. Becker W. Schreiber Werner Hofmann Eduard Hofmann Steinbeck H. Süllmann Griebel Rudolf Abderhalden Lars Erlandsen Heyns O. v. Soden C. Steinhoff J. Großfeld Frey-Wyssling W. Sutthoff Bäurle Willy Lindner Ed. Rentz Bandow Gerards K. N. v. Kaulla O. v. Soden Maria Cicconi Pawletta Baars R. Grau Lerche Beckel O. Windhausen Felicitas Rolleri Jesser Karl Boresch R. W. Seuffert K. Müller Schloemer K. Höll Johannes Wolf Brüning Patzsch W. Ludorff 《European Food Research and Technology》1941,81(3):223-288
123.
Chloride and Indium‐Chloride‐Complex Inorganic Ligands for Efficient Stabilization of Nanocrystals in Solution and Doping of Nanocrystal Solids 下载免费PDF全文
Vladimir Sayevich Chris Guhrenz Maria Sin Volodymyr M. Dzhagan Alexander Weiz Daniel Kasemann Eike Brunner Michael Ruck Dietrich R. T. Zahn Karl Leo Nikolai Gaponik Alexander Eychmüller 《Advanced functional materials》2016,26(13):2163-2175
Here, the surface functionalization of CdSe and CdSe/CdS core/shell nanocrystals (NCs) with compact chloride and indium‐chloride‐complex ligands is reported. The ligands provide not only short interparticle distances but additionally control doping and passivation of surface trap states, leading to enhanced electronic coupling in NC‐based arrays. The solids based on these NCs show an excellent electronic transport behavior after heat treatment at the relatively low temperature of 190 °C. Indeed, the indium‐chlorido‐capped 4.5 nm CdSe NC based thin‐film field‐effect transistor reaches a saturation mobility of μ = 4.1 cm2 (V s)?1 accompanied by a low hysteresis, while retaining the typical features of strongly quantum confined semiconductor NCs. The capping with chloride ions preserves the high photoluminescence quantum yield ( ≈ 66%) of CdSe/CdS core/shell NCs even when the CdS shell is relatively thin (six monolayers). The simplicity of the chemical incorporation of chlorine and indium species via solution ligand exchange, the efficient electronic passivation of the NC surface, as well as their high stability as dispersions make these materials especially attractive for wide‐area solution‐processable fabrication of NC‐based devices. 相似文献
124.
Alrun A. Günther Michael Sawatzki Petr Formánek Daniel Kasemann Karl Leo 《Advanced functional materials》2016,26(5):768-775
Doping is a powerful tool to overcome contact limitations in short‐channel organic field‐effect transistors (OFETs) and has been successfully used in the past to improve the charge carrier injection in OFETs. The present study applies this familiar concept to the architecture of vertical organic field‐effect transistors (VOFETs), which are often severely limited by injection due to their very short channel lengths. The present study shows that the performance of p‐type VOFETs with pentacene as an active material can be significantly enhanced by the addition of the common p‐dopant C60F36 as a thin injection layer underneath the VOFET source electrode, resulting in an increase of On‐state current and On/Off ratio by one order of magnitude. The present study further investigates mixed injection layers of pentacene and the p‐dopant and finds that the improvement is less pronounced than for the pure dopant layers and depends on the concentration of dopant molecules in the injection layer. Through application of the transfer length method to equivalent OFET geometries, the present study is finally able to link the observed improvement to a decrease in transfer length and can thus conclude that this length is a crucial parameter onto which further improvement efforts have to be concentrated to realize true short‐channel VOFETs. 相似文献
125.
126.
The microstructures of two as-cast heats of niobium-modified HP stainless steels were characterized. Particular attention
was paid to the interdendritic niobium-rich carbides formed during solidification of these alloys. At low magnifications,
these precipitates are grouped in colonies of similar lamellae. Higher magnifications revealed that the lamellae actually
obtain two distinct morphologies. The type I morphology exhibits broad planar interfaces with a smooth platelike shape. Type
II lamellae have undulating interfaces and an overall reticulated shape. To provide further insight into the origin of these
two different morphologies, the microstructure and crystallography of each have been studied in detail using high resolution
scanning electron microscopy, transmission electron microscopy, various electron diffraction methods (electron backscatter
diffraction (EBSD), selected area diffraction (SAD), and convergent beam electron diffraction (CBED)), and energy dispersive
X-ray spectroscopy. 相似文献
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130.
Multi-criteria location planning for public facilities in tsunami-prone coastal areas 总被引:3,自引:0,他引:3
We present a model for multi-objective decision analysis with respect to the location of public facilities as schools in areas
near to coasts, taking risks of inundation by tsunamis into account. A mathematical programming formulation with three objective
functions is given. The first objective function is a weighted mean of a minisum and a maximum coverage criterion. The second
objective function expresses risk by possible tsunami events; for quantifying this risk, a statistical model for tsunami occurrences
by Kaistrenko and Pinegina is applied. The third criterion represents costs. For the solution of the multi-objective optimization
problem, we propose a heuristic approach based on the NSGA-II algorithm and compare it with a decomposition technique where
the region under consideration is partitioned into smaller sub-regions, and the problem is solved for each separate subregion
either exactly or heuristically. Both approaches are tested on two real-life instances from southern Sri Lanka. 相似文献