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71.
Rémy Boulesteix Loïck Bonnet Alexandre Maître Lucie Chrétien Christian Sallé 《Journal of the American Ceramic Society》2017,100(3):945-953
Silica (SiO2) is widely used as sintering aid during vacuum sintering of YAG (Y3Al5O12)‐based transparent ceramics. These ceramics are mainly used for laser applications when they are doped with rare‐earth luminescent elements such as Yb3+ or Nd3+. By means of microstructural, chemical, dilatometry, and thermogravimetry analyses, this study has evidenced that sufficiently high amount of silica (ie above the solubility limit in YAG) forms intergranular transient liquid phase of mixed composition Y‐Al‐Si‐O that vaporizes rapidly for temperatures higher than 1350°C. As a result, silica content after sintering remains always lower than the solubility limit in YAG ceramics (ie lower than 900 ppm). Finally, vacuum sintering with an external source of gaseous Si was proven to be suitable to manufacture highly transparent Nd:YAG ceramics. 相似文献
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Changes in pheromone titer of oblique-banded leafroller,Choristoneura rosaceana,virgin females as a function of time of day,age, and temperature 总被引:1,自引:0,他引:1
Under a 16:8 hr light-dark photoperiod and 20C constant temperature, the titers of (Z)-11-tetradecenyl acetate (Z11–14:Ac), (E)-11-tetradecenyl acetate (E11–14:Ac) and (Z)-11-tetradecenol (Z11–14:OH) produced by different-agedChoristoneura rosaceana virgin females varied significantly during the scotophase, with the maximum titer occurring before the onset of calling in day-0 and day-3 females, while in day-5 females the titer remained constant throughout the calling period. There was a significant decrease in the titer of all pheromone components with age, explaining the lesser attractiveness of day-5 females relative to day-0 and day-3 females observed in the field. Under a cold thermocycle simulating condition during the second flight period in the fall, the titers of all pheromone components did not vary with time of day. There was a significant decrease in the amount ofZ11–14:Ac with age but no changes occurred in the minor components. Furthermore, for any given age tested, the amount of each component produced during the period of maximal calling activity remained relatively similar at the two temperature regimes. However, as with the expression of calling behavior, pheromone production was initiated earlier at cooler than at warmer temperatures. At both temperature regimes, female age and time of day influenced the ratio of each pheromone component. These results are discussed in relation to the hypothesis that by calling earlier, less attractive older females may increase their probability of mating. 相似文献
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In this paper we continue the study of variants of P colonies, called APCol systems, where the environment is given as a string and the model is an accepting system. We develop the concept by introducing the notion of the generating working mode. We then compare the power of a special subclass of APCol systems working in the generating mode to the power of register machines and context-free matrix grammars without appearance checking. 相似文献
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Cognition, Technology & Work - Causal-tree methods such as root cause analysis (RCA) are the oldest and the most widespread methods used to analyze the causes of adverse events. They are often... 相似文献
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Reviews the book, Psychologie positive et personnalite (Positive psychology and personality, activation of resources) by Firouzeh Mehran (2010). This is an interesting book on a captivating subject that has been little examined. Psychology has produced much more research on human distress than on people’s well-being. On the practical level, it presents a variety of techniques applicable in therapy. On the personal level, the book encourages the reader to modify current habits and suggests several ways of doing so. The book begins with personality theories prior to positive psychology that focused on healthy aspects of human existence; then examines current trends. Among other aspects, the author discusses spirituality and humor, their utility in clinical work and future possibilities. This is a theoretical book that offers practical ideas on acquiring healthy attitudes. Many techniques are suggested for therapists, and their clients, such as the principles and exercises of meditation in the mindfulness approach. It is not only an instructive source of knowledge but a tool for change and professional development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Lucie Kalvodova 《European Journal of Lipid Science and Technology》2010,112(10):1067-1067