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81.
Herein we disclose a simple palladium‐catalyzed transformation for the methoxylation of aromatic chlorides with tetramethoxyborate salts. The procedure provides a new and efficient synthetic tool for the introduction of a methoxy group into aromatic systems. In addition, the reaction can be achieved using a wide range of aromatic and heteroaromatic chlorides, the cheapest class of halides.

  相似文献   

82.
As part of the US‐Japan co‐operative research programme, this report presented at the 1985 UJNR Panel Conference reviews two workshops, the first held at Tsukuba in 1983 and the second at Berkeley, California in 1984. The highlights of those workshops are discussed here, and some conclusions drawn.  相似文献   
83.
The relative impact of several extrinsic attributes on informed hedonic liking and purchase intent for wine is measured by combining a blind hedonic test with an informed tasting of the same wine packaged in different product concepts. This study separated the relative effect of various attributes and also considers differences between consumers in their responsiveness to various product cues.Five-hundred and twenty-one regular wine consumers participated in a central location test in three German cities in 2005. Respondents first rated hedonic liking of a white wine in a blind condition, then evaluated elements of product concepts differing in four extrinsic attributes, region of origin, grape variety, brand and packaging style, before indicating their liking and purchase intent in an informed condition.Overall, label style and brand evaluation were the strongest drivers for informed liking followed by liking in the blind condition. Purchase intent was influenced directly only by informed liking and price evaluation; the effect of the extrinsic and intrinsic cues is mediated through informed liking. A latent class regression resulted in three consumer segments that differ in the responsiveness of their informed liking to the different product characteristics. Younger inexperienced consumers utilised a mix of various cues, wine experienced consumers based their evaluation mainly on grape variety and blind hedonic liking, and older frequent wine consumers were influenced most strongly by brand and packaging. These findings provide insights into the relative impact of product packaging, branding and labelling on overall product liking and indicate strong differences in how consumers respond to different product characteristics.  相似文献   
84.
Nano hydroxyapatite (nHA)–zirconia (ZrO2) composites have been produced by spark plasma sintering (SPS). During the SPS process low temperatures (600–950 °C) and short dwelling time (5 min) have been applied to avoid the decomposition of nHA as well as the reaction between nHA and ZrO2. The grain size of the sintered composites was between 200 and 1000 nm. Carbon diffusion was induced from the graphite die and layered composite structure was formed. These observations might be related to the spark plasma sintering side effects. The microstructure and mechanical properties of high hydroxyapatite content zirconia composites have been found to be influenced and strongly correlated with the specialties of SPS method.  相似文献   
85.
This work is intended to describe the design aspects and to characterize the functionality of a novel thermopile structure applicable for detecting millimetre range and THz radiation. The proposed thermopile consists of a series of micromachined poly-crystalline silicon thermocouple strips arranged linearly. This device can act as a series of antennas; its antenna-like operation was demonstrated clearly by the strong polarization dependence when detecting microwave radiation. The sensing principle is similar to the basic operation of bolometers in that the absorbed radiation heats up the semiconductor strips, but the temperature increment is detected by the Seebeck effect instead of the resistance change. Therefore there is no read-out current and the voltage output starts from zero. In the present work we are going to show the simulation of the current distribution. The fabrication of the device will also be outlined, as well as the results of measurements performed at 13, 100?GHz, and both in broad-band THz and in infrared radiation.  相似文献   
86.
The application of neutrality is a straightforward tool to preserve population diversity since it allows the genotype (on the represented search space) to be changed without affecting the corresponding fitness. To implement neutrality the literature suggests representational redundancy (more to one correspondence in genotype–phenotype mapping) although using it as a source of neutrality researchers uniformly reported better or worse results. Instead of applying representational redundancy here the utilization of pseudo redundancy as the source of neutrality is proposed, that is, neutrality is achieved by simple objective-fitness transformation while pseudo redundancy (as another redundancy interpretation) denotes more to one correspondence between objective-fitness domains by objective-fitness mapping. The contribution of this work is specified by the dynamic generational gap model introduced for evolutionary algorithms which appears when elitist strategy is used under neutrality by pseudo redundancy. This paper investigates the influence of dynamic generational gap model on the performance of a micro-genetic algorithm framework applied to achieve least cost water pump control policy for an industrial size water network distribution system. The presented constrained mixed-integer optimization problem is originated from the regional water network of the city of Sopron (60,000 citizens) located in Hungary. Here, the goal is to obtain intra-day pump schedule which minimizes the cost required for operation while satisfies the system constraints (water reservoir level limitations, pump flow and delivery regulations, pump energy consumption limitations) and fulfills the water requirement by the users.  相似文献   
87.
Software Quality Journal - Bug datasets have been created and used by many researchers to build and validate novel bug prediction models. In this work, our aim is to collect existing public source...  相似文献   
88.
We present a novel approach to implement a graph transformation engine based on standard relational database management systems (RDBMSs). The essence of the approach is to create database views for each rules and to handle pattern matching by inner join operations while negative application conditions by left outer join operations. Furthermore, the model manipulation prescribed by the application of a graph transformation rule is also implemented using elementary data manipulation statements (such as insert, delete, update).  相似文献   
89.
Current trends in cloud computing suggest that both large, public clouds and small, private clouds will proliferate in the near future. Operational requirements, such as high bandwidth, dependability and smooth manageability, are similar for both types of clouds and their underlying data center architecture. Such requirements can be satisfied with utilizing fully distributed, low-overhead mechanisms at the algorithm level, and an efficient layer 2 implementation at the practical level. On the other hand, owners of evolving private data centers are in dire need of an incrementally upgradeable architecture which supports a small roll-out and continuous expansion in small quanta. In order to satisfy both requirements, we propose Poincaré, a data center architecture inspired by hyperbolic tessellations, which utilizes low-overhead, greedy routing. On one hand, Poincaré scales to support large data centers with low diameter, high bisection bandwidth, inherent multipath and multicast capabilities, and efficient error recovery. On the other hand, Poincaré supports incremental plug & play upgradability with regard to both servers and switches. We evaluate Poincaré using analysis, extensive simulations and a prototype implementation.  相似文献   
90.
Prior research on the ability to solve the Piagetian invisible displacement task has focused on prerequisite representational capacity. This study examines the additional prerequisite of deduction. As in other tasks (e.g., conservation and transitivity), it is difficult to distinguish between behavior that reflects logical inference from behavior that reflects associative generalization. Using the role of negation in logic whereby negative feedback about one belief increases the certainty of another (e.g., a disjunctive syllogism), task-naive dogs (Canis familiaris; n?=?19) and 4- to 6-year-old children (Homo sapiens; n?=?24) were given a task wherein a desirable object was shown to have disappeared from a container after it had passed behind 3 separate screens. As predicted, children (as per logic of negated disjunction) tended to increase their speed of checking the 3rd screen after failing to find the object behind the first 2 screens, whereas dogs (as per associative extinction) tended to significantly decrease their speed of checking the 3rd screen after failing to find the object behind the first 2 screens. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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