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排序方式: 共有718条查询结果,搜索用时 170 毫秒
51.
Mui Siang Soh Sonsoles Amor Garcia Santamaria Evan Laurence Williams Marta Pérez‐Morales Henk J. Bolink Alan Sellinger 《Journal of Polymer Science.Polymer Physics》2011,49(7):531-539
A new class of solution processable dendrimers based on cyclic phosphazene (CP) cores have been prepared and used as host materials for blue and green organic light emitting diodes (OLEDs). The dendrimers are prepared in high yield from minimal step reactions, are soluble in common solvents for solution processing, are amorphous, and have excellent thermal properties necessary for application in OLEDs. OLED efficiencies of 10.3 cd/A (4.2 lm/W) and 35.3 cd/A (33.5 lm/W) were achieved using commercially available FIrpic and Ir(mppy)3 as blue and green phosphorescent emitters, respectively. These efficiencies were 2× higher than control devices prepared using poly(N‐vinylcarbazole), the most commonly used host material in solution processed phosphorescent OLEDs. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献
52.
Reflection and transmission of traveling and evanescent waves by a layer of material with a negative index of refraction (NIM) is studied by means of the Fresnel coefficients. We derive their values in the “NIM limit”, and we show that this limit is consistent with the exact solution. It is also indicated that simply substituting the negative values of the relative permittivity and permeability of the NIM material into the exact solution leads to incorrect results for evanescent waves. 相似文献
53.
54.
Henk J.A.M. Heijmans Batrice Pesquet-Popescu Gemma Piella 《Applied and Computational Harmonic Analysis》2005,18(3):252-281
In this paper, we propose a technique for building adaptive wavelets by means of an extension of the lifting scheme. Our scheme comprises an adaptive update lifting step and a fixed prediction lifting step. The adaptivity consists hereof that the system can choose between two different update filters, and that this choice is triggered by the local gradient of the original signal. If the gradient is large (in some seminorm sense) it chooses one filter, if it is small the other. We derive necessary and sufficient conditions for the invertibility of such an adaptive system for various scenarios. Furthermore, we present some examples to illustrate our theoretical results. 相似文献
55.
This paper is concerned with the coordination of inventory control in three-echelon serial and distribution systems under
decentralized control. All installations in these supply chains track echelon inventories. Under decentralized control the
installations will decide upon base stock levels that minimize their own inventory costs. In general these levels do not coincide
with the optimal base stock levels in the global optimum of the chain under centralized control. Hence, the total cost under
decentralized control is larger than under centralized control.
To remove this cost inefficiency, two simple coordination mechanisms are presented: one for serial systems and one for distribution
systems. Both mechanisms are initiated by the most downstream installation(s). The upstream installation increases its base
stock level while the downstream installation compensates the upstream one for the increase of costs and provides it with
a part of its gain from coordination. It is shown that both coordination mechanisms result in the global optimum of the chain
being the unique Nash equilibrium of the corresponding strategic game. Furthermore, all installations agree upon the use of
these mechanisms because they result in lower costs per installation. The practical implementation of these mechanisms is
discussed. 相似文献
56.
Gert Vegter. 《Mathematics of Computation》2000,69(230):691-720
Some recent methods of Computer Aided Geometric Design are related to the apolar bilinear form, an inner product on the space of homogeneous multivariate polynomials of a fixed degree, already known in 19th century invariant theory. Using a generalized version of this inner product, we derive in a straightforward way some of the recent results in CAGD, like Marsden's identity, the expression for the de Boor-Fix functionals, and recursion schemes for the computation of B-patches and their derivatives.
57.
We introduce the class of ordinal games with a potential, which are characterized by the absence of weak improvement cycles,
the same condition used by Voorneveld and Norde (1997) for ordinal potential games. 相似文献
58.
Kamphuis MM Johnston AP Such GK Dam HH Evans RA Scott AM Nice EC Heath JK Caruso F 《Journal of the American Chemical Society》2010,132(45):15881-15883
Targeted delivery of drugs to specific cells allows a high therapeutic dose to be delivered to the target site with minimal harmful side effects. Combining targeting molecules with nanoengineered drug carriers, such as polymer capsules, micelles and polymersomes, has significant potential to improve the therapeutic delivery and index of a range of drugs. We present a general approach for functionalization of low-fouling, nanoengineered polymer capsules with antibodies using click chemistry. We demonstrate that antibody (Ab)-functionalized capsules specifically bind to colorectal cancer cells even when the target cells constitute less than 0.1% of the total cell population. This precise targeting offers promise for drug delivery applications. 相似文献
59.
Mark Eggink Maikel Wijtmans Ansgar Kretschmer Jeroen Kool Henk Lingeman Iwan J. P. de Esch Wilfried M. A. Niessen Hubertus Irth 《Analytical and bioanalytical chemistry》2010,397(2):665-675
Based on the template of a recently introduced derivatization reagent for aldehydes, 4-(2-(trimethylammonio)ethoxy)benzeneaminium
dibromide (4-APC), a new derivatization agent was designed with additional features for the analysis and screening of biomarkers
of lipid peroxidation. The new derivatization reagent, 4-(2-((4-bromophenethyl)dimethylammonio)ethoxy)benzenaminium dibromide
(4-APEBA) contains a bromophenethyl group to incorporate an isotopic signature to the derivatives and to add additional fragmentation
identifiers, collectively enhancing the abilities for detection and screening of unknown aldehydes. Derivatization can be
achieved under mild conditions (pH 5.7, 10 °C). By changing the secondary reagent (1-ethyl-3-(3-dimethylaminopropyl) carbodiimide
instead of sodium cyanoborohydride), 4-APEBA is also applicable to the selective derivatization of carboxylic acids. Synthesis
of the new label, exploration of the derivatization conditions, characterization of the fragmentation of the aldehyde and
carboxylic acid derivatives in MS/MS, and preliminary applications of the labeling strategy for the analysis of aldehydes
in urine and plasma are described. 相似文献
60.
Ferry Heus Martin Giera Gerdien E. de Kloe Dick van Iperen Joost Buijs Tariq T. Nahar August B. Smit Henk Lingeman Iwan J. P. de Esch Wilfried M. A. Niessen Hubertus Irth Jeroen Kool 《Analytical and bioanalytical chemistry》2010,398(7-8):3023-3032
One way to profile complex mixtures for receptor affinity is to couple liquid chromatography (LC) on-line to biochemical detection (BCD). A drawback of this hyphenated screening approach is the relatively high consumption of sample, receptor protein and (fluorescently labeled) tracer ligand. Here, we worked toward minimization of sample and reagent consumption, by coupling nano-LC on-line to a light-emitting diode (LED) based capillary confocal fluorescence detection system capable of on-line BCD with low-flow rates. In this fluorescence detection system, a capillary with an extended light path (bubble cell) was used as a detection cell in order to enhance sensitivity. The technology was applied to a fluorescent enhancement bioassay for the acetylcholine binding protein, a structural analog of the extracellular ligand-binding domain of neuronal nicotinic acetylcholine receptors. In the miniaturized setup, the sensitive and low void volume LED-induced confocal fluorescence detection system operated in flow injection analysis mode allowing the measurement of IC50 values, which were comparable with those measured by a conventional plate reader bioassay. The current setup uses 50 nL as injection volume with a carrier flow rate of 400 nL/min. Finally, coupling of the detection system to gradient reversed-phase nano-LC allowed analysis of mixtures in order to identify the bioactive compounds present by injecting 10 nL of each mixture. 相似文献