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271.
Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO2 and the inner layer a mixture of TiO and Ti2O. The thickness of the Ti2O, TiO and anatase-TiO2 were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti2O to tetragonal TiO2 phase transformation rate induced by the substitution of Li+ for Ti4+ in the oxide layer.  相似文献   
272.
273.
The grain size variation in a gradient surface produced by a punching and recovery process on a Cu-30Ni alloy has been observed by atomic force microscopy. The friction characteristics of the gradient surface in a 3.5 wt% NaCl solution were investigated using a micro-indenter probe, a pin-on-disc type tribometer, a strain sensor and an optical microscope. The results showed that the hardness and grain size can be well represented by the Hall–Petch relationship when the gain size is more than 30?nm. The wear rate, friction coefficient and adhesive force all increase depth below the surface. These variations are attributed to a gradual increasing grain size with depth. The morphologies of the worn track were also studied to understand further the corrosive wear behaviour of gradient surfaces.  相似文献   
274.
The mechanical softening behaviour of micrometre-scale metals (free-standing metal foils and wires) with decreasing either the geometrical or the microstructural scale (i.e. the smaller, the weaker) has recently been reported. Here, we present a mechanism-based model to understand the softening behaviour, which is based on competition between the effects of surface grain relaxation and the interior grain strengthening effect. The model describes well the yield stress of Cu foils with different ratios of the thickness to grain size.  相似文献   
275.
This study examined the relationships between proactive personality and employee creativity and the moderating roles of job creativity requirement and supervisor support for creativity in activating proactive personality associated with employee creativity. To provide a rigorous test of the hypotheses, we conducted a field study from a sample of 157 employee–supervisor pairs in South Korea. The results revealed that a proactive personality was positively associated with employee creativity. In addition, job creativity requirement and supervisor support for creativity jointly influenced the relationship between proactive personality and employee creativity. Specifically, proactive employees exhibited the highest employee creativity when job creativity requirement and supervisor support for creativity were both high.  相似文献   
276.
We asked whether the influence of an invisible prime on movement is dependent on conscious movement expectations. Participants reached to a central target, which triggered a directional prime–mask arrow sequence. Participants were instructed that the visible arrows (masks) would most often signal a movement modification in a specific (biased) direction. Kinematic analyses revealed that responses to the visible mask were influenced by participants’ intentional bias, as movements were fastest when the more probable mask was displayed. In addition, responses were influenced by the invisible prime without regard to its relationship to the more probable mask. Analysis of the time of initial trajectory modifications revealed that both primes influenced responses in a similar manner after accounting for participants’ bias. These results imply that invisible stimuli automatically activate their associated responses and that unconscious priming of the motor system is insensitive to the conscious expectations of the participant making the pointing movements.  相似文献   
277.
This study examined the Chinese name-pronunciation effect. The easy-to-pronounce and difficult-to-pronounce Chinese names were created using the same characters in order to control for visual perceptual and conceptual fluency. In Experiment 1, participants rated each name in terms of liking, electability as a state leader, income level, and baby name preference. An additional rating of prevalence was used to estimate familiarity. In Experiment 2, participants did not read the name aloud before rating and performed intentional recall and recognition tests. In both experiments, the easy-to-pronounce names were rated higher than difficult-to-pronounce names on liking. This effect generalized to judgments of electability and baby name preference but not to prevalence and income level. There were no differences in memory performances between the two types of names. Results are discussed in terms of the boundary condition of the name-pronunciation effect and the advantage of using Chinese names to study this effect.  相似文献   
278.
Having language delay—one of the common neurodevelopmental difficulties during childhood—does not only imply an impairment in communication in the 1st few years of life. Previous studies have suggested that language problems have long-term implications for social, emotional, and intellectual development. Researchers have found that early identification and intervention of speech and language delay yields better treatment effects. However, unlike most of the motor developmental assessment tools, language assessment tools are not readily transferred across cultures because of the different linguistic features and the developmental stages of such features in a particular language or dialect. The present study presents an empirical example of the initial development of a culturally sensitive screening protocol, using vocabulary size as the indicator to minimize the effect of linguistic differences.  相似文献   
279.
The authors explored the extent to which 5th- and 6th-grade students’ anticipated responses to hypothetical peers with undesirable characteristics (e.g., being overweight) are influenced by information that each peer (a) desired (or did not desire) to change the characteristic, (b) exerted effort (or did not exert effort) to change the characteristic, and (c) was successful (or unsuccessful) in changing the characteristic. In general, the children anticipated responding more favorably to peers who were successful in overcoming an undesirable characteristic than those who were unsuccessful. However, across both outcome conditions, peers who wanted to change and exerted effort to change were rated more favorably than were peers who reported no effort to change an undesirable characteristic, regardless of whether or not they had expressed a desire to change that characteristic. For peers whose failure to change an undesirable characteristic was associated with no effort to change, those who expressed a desire to change were rated more favorably than those who expressed no desire to change.  相似文献   
280.
E. A. Southwell &; M. Merbaum (Eds.). Personality: Readings in Theory and Research. (2nd ed.) Belmont, Calif.: Brooks/Cole, 1971, 422 pages. Reviewed by Benjamin Beit-Hallahmi  相似文献   
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