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121.
Organic batteries are considered as environmentally friendly alternative to lithium-ion batteries due to the application of transition metal-free redox-active polymers. One well-established polymer is poly(3-vinyl-N-methylphenothiazine) (PVMPT) with a fast reversibility of the electrochemical redox reaction at a potential of 3.5 V versus Li|Li+. The oxidized PVMPT is soluble in many standard battery electrolytes, which diminishes its available specific capacity but at the same time can lead to a unique charge/discharge mechanism involving a redeposition process upon discharge. Herein, the influence of different conductive carbon additives and their properties, e.g., specific surface area, pore size distribution, and electrical conductivity, on the dissolution behavior of oxidized PVMPT is investigated. Compared to the state-of-the-art conductive carbon Super C65 employed in many organic battery electrodes, Ketjenblack EC-300J and EC-600J reduce the dissolution of the oxidized PVMPT due to better immobilization on the carbon additive and in the resulting 3D structure of the electrode, as assessed by N2-physisorption, electrochemical, UV–vis spectroscopy and scanning electron microscopy investigations. The studies demonstrate that a dense packing of the carbon particles in the electrode is decisive for the stable immobilization of PVMPT while maintaining its long-term cycling performance.  相似文献   
122.
Order picking involves the retrieval of articles from their storage locations in order to satisfy customer requests. A major issue in manual order picking systems is the transformation and consolidation of customer orders into picking orders (order batching). In practice, customer orders have to be completed by certain due dates in order to avoid shipment or production delays. The composition of the picking orders, their processing times and the sequence according to which they are released have a significant impact on whether and to which extent due dates are violated. This paper presents how metaheuristics can be used in order to minimize the total tardiness for a given set of customer orders. The first heuristic is based on Iterated Local Search, the second is inspired by the Attribute-Based Hill Climber, a heuristic based on a simple tabu search principle. In a series of extensive numerical experiments, the performance of these metaheuristics is analyzed for different classes of instances. We will show that the proposed methods provide solutions which may allow order picking systems to operate more efficiently. Solutions can be improved by 46% on average, compared to those obtained with standard constructive heuristics such as the Earliest Due Date rule.  相似文献   
123.
124.
More than 100 bacterial isolates from various marine habitats were screened for AHL production by using gfp reporter constructs based on the lasR system of Pseudomonas aeruginosa and the luxR system of Vibrio fischeri. Of the 67 Alphaproteobacteria tested, most of which belonged into the so-called Roseobacter clade, 39 induced fluorescence in either one or both sensor strains up to 103-fold compared to controls. Acylated homoserine lactones were identified by GC-MS analysis and shown to have chain lengths of C8, C10, C13-C16, and C18. One or two double bonds were often present, while a keto or hydroxyl group occurred only rarely in the side chain. Most strains produced several different AHLs. C18-en-HSL and C18-dien-HSL were produced by Dinoroseobacter shibae, an aerobic anoxygenic phototrophic bacterium isolated from dinoflagellates, and are among the longest AHLs found to date. Z7-C14-en-HSL, which has previously been detected in Rhodobacter sphaeroides, was produced by Roseovarius tolerans and Jannaschia helgolandensis. This signal molecule was synthesised and shown to induce a similar response to the culture supernatant in the respective sensor strain. The widespread occurrence of quorum-sensing compounds in marine Alphaproteobacteria, both free-living strains and those associated to eukaryotic algae, points to a great importance of this signalling mechanism for the adaptation of the organisms to their widely different ecological niches.  相似文献   
125.
The response of the two eulophid egg parasitoid species Chrysonotomyia ruforum and Dipriocampe diprioni to sex pheromones of their sawfly hosts Diprion pini and Neodiprion sertifer was studied in olfactometer bioassays. Females of C. ruforum were arrested when exposed to odor of the tested major sex pheromone components of Diprion pini [acetate and propionate of (2S,3R,7R)-3,7–dimethyl-2–tridecanol] or Neodiprion sertifer [(2S,3S,7S)-3,7–dimethyl-2–pentadecyl acetate]. This behavioral response of C. ruforum was observed whether (1) parasitoid females had oviposition experience with D. pini eggs or not, (2) parasitoid females emerged from D. pini eggs of a French population or from N. sertifer eggs of a Finnish population, and (3) the tested sex pheromone concentration was low (1 ng/l hexane) or high (100 ng/l hexane). However, C. ruforum did not behaviorally respond to a stereoisomer of the major sex pheromone component of N. sertifer, which is known to act as a sex pheromone antagonist [antagonist = (2S,3R,7R)-3,7–dimethyl-2–pentadecyl acetate]. Thus, C. ruforum responded stereospecifically to the S,S,S configured pheromone of N. sertifer, but not to the S,R,R configuration. Females of the parasitoid D. diprioni were also arrested by the tested major sex pheromone components of the host D. pini. The kairomonal effects of diprionid host sex pheromones on these egg parasitoids are compared to known responses of egg parasitoids to lepidopteran sex pheromones.  相似文献   
126.
Enhancing the efficiency and lifetime of light emitting electrochemical cells (LEC) is the most important challenge on the way to energy efficient lighting devices of the future. To avail this, emissive Ir(III) complexes with fluoro‐substituted cyclometallated ligands and electron donating groups (methyl and tert ‐butyl)‐substituted diimine ancillary (N^N) ligands and their associated LEC devices are studied. Four different complexes of general composition [Ir(4ppy)2(N^N)][PF6] (4Fppy = 2‐(4‐fluorophenyl)pyridine) with the N^N ligand being either 2,2′‐bipyridine ( 1 ), 4.4′‐dimethyl‐2,2′‐bipyridine ( 2 ), 5.5′‐dimethyl‐2,2′‐bipyridine ( 3 ), or 4.4′‐di‐tert ‐butyl‐2,2′‐bipyridine ( 4 ) are synthesized and characterized. All complexes emit in the green region of light with emission maxima of 529–547 nm and photoluminescence quantum yields in the range of 50.6%–59.9%. LECs for electroluminescence studies are fabricated based on these complexes. The LEC based on ( 1 ) driven under pulsed current mode demonstrated the best performance, reaching a maximum luminance of 1605 cd m?2 resulting in 16 cd A?1 and 8.6 lm W?1 for current and power efficiency, respectively, and device lifetime of 668 h. Compared to this, LECs based on ( 3 ) and ( 4 ) perform lower, with luminance and lifetime of 1314 cd m?2, 45.7 h and 1193 cd m?2, 54.9 h, respectively. Interestingly, in contrast to common belief, the fluorine content of the Ir‐iTMCs does not adversely affect the LEC performance, but rather electron donating substituents on the N^N ligands are found to dramatically reduce both performance and stability of the green LECs. In light of this, design concepts for green light emitting electrochemical devices have to be reconsidered.  相似文献   
127.
Sharing of structured data in decentralized environments is a challenging problem, especially in the absence of a global schema. Social network structures map network links to semantic relations between participants in order to assist in efficient resource discovery and information exchange. In this work, we propose a scheme that automates the process of creating schema synopses from semantic clusters of peers which own autonomous relational databases. The resulting mediated schemas can be used as global interfaces for relevant queries. Active nodes are able to initiate the group schema creation process, which produces a mediated schema representative of nodes with similar semantics. Group schemas are then propagated in the overlay and used as a single interface for relevant queries. This increases both the quality and the quantity of the retrieved answers and allows for fast discovery of interest groups by joining peers. As our experimental evaluations show, this method increases both the quality and the quantity of the retrieved answers and allows for faster discovery of semantic groups by joining peers.  相似文献   
128.
Verena E. Ziegler 《Polymer》2005,46(22):9265-9273
Drop sizes and drop size distributions were determined by means of an optical shear cell in combination with an optical microscope for the systems polyisobutylene/poly(dimethylsiloxane) [I] and poly(dimethyl-co-methylphenylsiloxane)/poly(dimethylsiloxane) [II] at low concentrations of the suspended phases and at different constant shear rates ranging from 10 to 0.5 s−1. After pre-shearing the two-phase mixtures [I: 50 s−1; II: 100 s−1] for the purpose of producing small drop radii, the shear rate was abruptly reduced to the preselected value and coalescence was studied as a function of time. In all cases one approaches dead end drop radii, i.e. breakup is absent. The drop size distributions are for sufficiently long shearing always unimodal, but within the early stages of coalescence they are in some cases bimodal; the shape of the different peaks is invariably Gaussian. The results are discussed by means of Elmendorp diagrams and interpreted in terms of collision frequencies and collision efficiencies.  相似文献   
129.
The potential of direct heating of reactors is in this study exemplified by an aftertreatment system for passenger vehicles. Experimental and numerical investigations on thermal characteristics of catalyst supports were conducted for both a cordierite and a conductive hybrid ceramic substrate, whereby the latter offers the possibility of electric heating. A considerable reduction of critical heat-up time after engine startup is evident for the conductive hybrid ceramic carrier, which consequently allows an increase in emission reduction efficiency.  相似文献   
130.
Rogaratinib (BAY 1163877) is a highly potent and selective small‐molecule pan‐fibroblast growth factor receptor (FGFR) inhibitor (FGFR1–4) for oral application currently being investigated in phase 1 clinical trials for the treatment of cancer. In this publication, we report its discovery by de novo structure‐based design and medicinal chemistry optimization together with its pharmacokinetic profile.  相似文献   
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