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31.
Due to the increasing importance of producing and consuming energy more sustainably, Energy Informatics (EI) has evolved into a thriving research area within the CS/IS community. The article attempts to characterize this young and highly dynamic field of research by describing current EI research topics and methods and provides an outlook of how the field might evolve in the future. It is shown that two general research questions have received the most attention so far and are likely to dominate the EI research agenda in the coming years: How to leverage information and communication technology (ICT) to (1) improve energy efficiency, and (2) to integrate decentralized renewable energy sources into the power grid. Selected EI streams are reviewed, highlighting how the respective research questions are broken down into specific research projects and how EI researchers have made contributions based on their individual academic background.  相似文献   
32.
Structured dispersion particles suitable for pressure sensitive adhesives (PSA) were synthesized via swelling polymerization technique (EP 359562). Particles consisting of poly(n‐butyl acrylate) copolymerized with different types of carboxylic acids were used as seeds. The final particles were synthesized by swelling polymerization process, using 6 wt % styrene or 6 wt % methyl methacylate. The resulting particle morphology was analyzed by atomic force microscopy (AFM) and transmission electron microscopy (TEM). From previous works (Coll Surf A 2001, 183–185, 725–737; J Appl Polym Sci 2004, 91, 2610–2623) where two‐step emulsion polymerization was used on similar particles, it is expected that the particle morphology is affected by the polarity of the monomer used for swelling polymerization because of the phase compatibility (thermodynamic parameter). In this work, the seed particles used were always of a glass transition temperature (Tg) below polymerization temperature. The diffusion of the growing polymer chains from the swelling polymerization is therefore mainly affected by their own Tg and the influence of the carboxy groups on the chain length of the entering radicals (kinetic parameter). The different morphologies of the single particles are discussed qualitatively. The effects of reaction parameters are compared with the results given in the previous work. The structure of the corresponding dispersion films was characterized using AFM. Correlations to macroscopic properties such as the cohesive strength and peel adhesion to different substrates are discussed. The results are also compared with the application properties of the corresponding unmodified particles, statistical copolymers, and to blends with small sized PMMA or PS particles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1444–1455, 2006  相似文献   
33.
Research on the ergosterol biosynthetic pathway in fungi has focused on the identification of the specific sterol structure required for normal membrane structure and function and for completion of the cell cycle. The pathway and its end product are also the targets for a number of antifungal drugs. Identification of essential steps in ergo-sterol biosynthesis could provide new targets for the development of novel therapeutic agents. Nine of the eleven genes in the portion of the pathway committed exclusively to ergosterol biosynthesis have been cloned, and their essentiality for aerobic growth has been determined. The first three genes;ERG9 (squalene synthase),ERG1 (squalene epoxidase), andERG7 (lanosterol synthase), have been cloned and found to be essential for aerobic viability since their absence would result in the cell being unable to synthesize a sterol molecule. The remaining eight genes encode enzymes which metabolize the first sterol, lanosterol, to ultimately form ergosterol. The two earliest genes,ERG11 (lanosterol demethylase) andERG24 (C-14 reductase), have been cloned and found to be essential for aerobic growth but are suppressed by mutations in the C-5 desaturase (ERG3) gene andfen1 andfen2 mutations, respectively. The remaining cloned genes,ERG6 (C-24 methylase),ERG2 (D8Æ7 isomerase),ERG3 (C-5 desaturase), andERG4 (C-24(28) reductase), have been found to be nonessential. The remaining genes not yet cloned are the C-4 demethylase and the C-22 desaturase (ERG5).  相似文献   
34.
Urethanes of cellobiose and cellulose-containing uretdione groups are synthesized by the reaction of aliphatic and aromatic diisocyanate uretdiones with the saccharides. The syntheses are performed as a heterogeneous reaction in dimethyl acetamide using dibutyl tin dilaurate as a catalyst, as well as a homogeneous reaction in dimethyl acetamide-lithium chloride. Thus, Semisynthetic prepolymers are formed that offer the reactivity of (blocked) isocyanate groups. To demonstrate their reactivity, ring opening of the uretdiones is performed by the addition of a secondary amine to yield the corresponding ureas.  相似文献   
35.
The reactor systems used for the Fischer-Tropsch synthesis, fixed bed, fluidized bed and slurry bed, are compared on the basis of space time yield (STY) and level of conversion obtainable under the same set of feed and operating conditions. The slurry bed and fluidized bed reactor were compared on the basis of a first order reaction model. The performance of these two reactors was found to be comparable at low values of WHSV, but at higher values of WHSV, the fluidized bed reactor gave higher conversions and STY. A power law kinetic expression was used to compare the performance of the slurry bed and fixed bed reactors. Higher conversions and STY were obtained from the fixed bed with varying WHSV. This may be due to the omission of the intra and inter phase mass transfer resistances in the modelling of the fixed bed reactor.  相似文献   
36.

Fall und Kommentare

Gibt es eine Pflicht zum pr?natalen Nichtwissen?  相似文献   
37.
The Sr(B'0.5Ta0.5)O3 ceramics where B'=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Y, Er, and Yb have been prepared by the conventional solid-state ceramic route and their microwave dielectric properties have been investigated. The structure and microstructure of the ceramics have been characterized by X-ray diffraction and scanning electron microscope techniques. The relative permittiviy (ɛr) varies linearly with B'-site ionic radii, except for La, and the temperature coefficient of resonant frequency (τf) varies linearly with the tolerance factor. The Sr(B'0.5Ta0.5)O3 ceramics have ɛr in the range 25.9–32, Q u× f =4500–54 300 GHz, and τf=−79 to −42 ppm/°C. A slight deviation from stoichiometry affects the dielectric properties of these double perovskites. Partial substitution of Ba for Sr could tune the dielectric properties. Addition of rutile (TiO2) lowered the sintering temperature and improved the dielectric properties of Sr(B'0.5Ta0.5)O3 ceramics.  相似文献   
38.

Definition of the problem

This paper deals with the question whether the current German intellectual property right on pharmaceuticals is morally justifiable. To answer this question, I will map the relevant discourse and arrange the different positions with respect to their level of abstraction.

Arguments

I underline that both deontological and consequentialist arguments point out the moral deficits within the system.

Conclusion

The consequentialist position emphasizes the unsatisfying relationship between patented pharmaceutical costs and the number of innovations on the market. The deontological approach on the other hand highlights the dangers to citizens’ autonomy.
  相似文献   
39.

Definition of the problem

Ruth Macklin’s influential essay “Dignity is a useless concept” has revitalized a broad debate on the question whether the concept of dignity is meaningful in medical ethics. In this paper, I would like to examine Macklin’s so-called redundancy claim: according to this claim, the concept of human dignity can be replaced by other concept(s)—the concept of autonomy most prominent among them. What is the meaning of this claim?

Arguments

Starting from an analysis of Macklin’s arguments, I am going to show under which conditions a redundancy claim indeed leads to the eliminating consequences emphasized by its defenders—we should abandon the concept of dignity.

Conclusion

I am going to identify the advantages of her position both in comparison with more radical eliminative standpoints as well as positions that regard it as valid, but unanalyzable.  相似文献   
40.
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