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91.
92.
Editorial     
This special issue is devoted to a study of psychological perspectives of aging and gerontology. The present issue covers topics and themes that relate broadly to the perceptions and psychological functioning of older adults: Their motivations, their happiness and activities, their personal meanings of life and quality of life concerns, their sexual expressions, their television viewing, and how all these relate to successful aging. Also included are perspective-taking papers on problems of stress and depression and how these relate to the psychological health and welfare of older adults. The reader will find a rich assortment of research-based gerontology papers attesting to the vigorous activity of Canadian psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
93.
Zusammenfassung Die beschriebene Methode erlaubt eine zuverlässige Erkennung der Sorte Kranich aus insgesamt 9 untersuchten Weizensorten innerhalb von 5 Stunden.
Disc-electrophoresis of the water-soluble proteins of some wheat varieties
Summary The method described allows a reliable detection of the variety Kranich out of 9 varieties investigated within 5 h.


Fräulein D. Schweiger danken wir für die ausgezeichnete Mitarbeit

Die untersuchten Mehle wurden uns freundlicherweise von Herrn Dr. H. D. Jodlbauer, Hameln, zur Verfügung gestellt  相似文献   
94.
In recent years much interest has been generated in a quality of reduced sensitivity RDX (RS‐RDX), like I‐RDX® which, when incorporated in cast cure and even pressable plastic bonded explosives (PBX compositions), can confer reduced shock sensitivity as measured through gap test. At crystal level, lot of work has been done to try to determine which property or properties may explain the behaviour of the corresponding cast PBX composition. But up to now, and despite an international inter‐laboratory comparison (Round Robin) of seven lots of RDX from five different manufacturers conducted from 2003 to 2005, even if some techniques lead to interesting results, there is no dedicated specification to apply to RS‐RDX. This quality (I‐RDX®) has proved to retain its low sensitivity even after ageing, which does not seem to be the case for standard RDX produced by the Bachmann process (when re‐crystallized under I‐RDX conditions in order to obtain RS‐RDX). It has been shown that the higher sensitivity of RDX produced by the Bachmann process, or the evolution of sensitivity after ageing of RS‐RDX produced from Bachmann RDX may be linked to the presence of octogen (HMX) during the crystallization process. In order to check such hypothesis, low HMX content RDX produced by the Bachmann process has been prepared and evaluated in cast PBX composition (PBX N 109). Results of the characterization of such quality of RDX and its evaluation in cast PBX composition as well as ageing behaviour are presented and discussed; there are indications that removal of HMX from Bachmann RDX may lead to RS‐RDX, which retains its RS character even after ageing.  相似文献   
95.
Observation of highly dynamic processes inside living cells at the single molecule level is key for a better understanding of biological systems. However, imaging of single molecules in living cells is usually limited by the spatial and temporal resolution, photobleaching and the signal-to-background ratio. To overcome these limitations, light-sheet microscopes with thin selective plane illumination, for example, in a reflected geometry with a high numerical aperture imaging objective, have been developed. Here, we developed a reflected light-sheet microscope with active optics for fast, high contrast, two-colour acquisition of -stacks. We demonstrate fast volume scanning by imaging a two-colour giant unilamellar vesicle (GUV) hemisphere. In addition, the high contrast enabled the imaging and tracking of single lipids in the GUV cap. The enhanced reflected scanning light-sheet microscope enables fast 3D scanning of artificial membrane systems and potentially live cells with single-molecule sensitivity and thereby could provide quantitative and molecular insight into the operation of cells.  相似文献   
96.
Abstract: Pareto optimal designs are the best designs that can be produced for a given problem formulation for a given set of criteria when the criteria are not combined in any way. If the goal is to improve the performance in those criteria, then it is possible to manipulate the problem formulation to achieve an improvement. The approach adopted is to encode the formulation in a genetic algorithm and to allow the formulation to evolve in the direction of improving Pareto optimal designs. A set of rules (in the form of a shape grammar), the execution of which produces a design, is encoded as the genes in a genetic algorithm. However, the rule set is allowed to evolve, not just the order of execution of rules. We present an example demonstrating both the approach and its utility in improving Pareto optimal designs.  相似文献   
97.
Metallurgical and Materials Transactions A - Hadfield Steel shows high strain hardening which can be linked to its ability to form twins during mechanical loading. Twinning in Hadfield Steel is...  相似文献   
98.
Parabolic trough power plants are currently the most commercially applied systems for CSP power generation. To improve their cost-effectiveness, one focus of industry and research is the development of processes with other heat transfer fluids than the currently used synthetic oil. One option is the utilization of water/steam in the solar field, the so-called direct steam generation (DSG).Several previous studies promoted the economic potential of DSG technology (Eck et al., 2008b, Price et al., 2002, Zarza, 2002). Analyses’ results showed that live steam parameters of up to 500 °C and 120 bars are most promising and could lead to a reduction of the levelized electricity cost (LEC) of about 11% (Feldhoff et al., 2010). However, all of these studies only considered plants without thermal energy storage (TES).Therefore, a system analysis including integrated TES was performed by Flagsol GmbH and DLR together with Solar Millennium AG, Schott CSP GmbH and Senior Berghöfer GmbH, all Germany. Two types of plants are analyzed and compared in detail: a power plant with synthetic oil and a DSG power plant. The design of the synthetic oil plant is very similar to the Spanish Andasol plants (Solar Millennium, 2009) and includes a molten salt two-tank storage system. The DSG plant has main steam parameters of 500 °C and 112 bars and uses phase change material (PCM) for the latent and molten salt for the sensible part of the TES system. To enable comparability, both plants share the same gross electric turbine capacity of 100 MWel, the same TES capacity of 9 h of full load equivalent and the same solar multiple of the collector field of about two.This paper describes and compares both plants’ design, performance and investment. Based on these results, the LEC are calculated and the DSG plant’s potential is evaluated. One key finding is that with currently proposed DSG storage costs, the LEC of a DSG plant could be higher than those of a synthetic oil plant. When considering a plant without TES on the other hand, the DSG system could reduce the LEC. This underlines the large influence of TES and the still needed effort in the development of a commercial storage system for DSG.  相似文献   
99.
We used in-situ X-ray Photoelectron Spectroscopy (XPS) to study the oxidation process of a cluster-assembled metallic titanium film exposed to molecular oxygen at room temperature. The nanostructured film has been grown on a Si(111) substrate, in ultra high vacuum conditions, by coupling a supersonic cluster beam deposition system with an XPS experimental chamber. Our results show that upon in-situ oxygen exposure Ti3 + is the first oxidation state observed, followed by Ti4 +, whereas Ti2 + is practically absent during the whole process. Our results compare well with the existing literature on Ti films produced using other techniques.  相似文献   
100.
The development of cleaner and renewable energy sources are needed in order to reduce dependency and global warming. Wood pellets are a clean renewable fuel and has been considered as one of the substitutes for fossil fuels. In Argentina, large quantities of sawmill residues are still unused and wood pellets production could be seen as both, as an environmental solution and an extra economical benefit. The general aim of this study was to determine the wood pellets production costs and energy consumption under different framework conditions in northeast Argentina. The specific costs of wood pellets for the different scenarios showed relative lower costs comparing to the ones reported in other studies, ranging from 35 to 47 €/Mgpellets. Raw material costs represented the main cost factor in the calculation of the total pellets production costs. A lower specific production cost was observed when 50% of the raw material input was wood shavings. The specific electricity consumption per metric ton of pellet was lower in scenarios with higher production rate. Lower heat energy consumption was observed in scenarios that have a mixed raw material input. The most promising framework condition for Northeast Argentina, in terms of costs effectiveness and energy consumption could be acquired with production rates of 6 Mg/h with sawdust and wood shavings as raw material. However, simultaneous increment of the electricity by 50% and raw material price by 100% may increase the specific costs up to 50%.  相似文献   
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