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71.
72.
Besides the well-known cube-on-cube orientation relationship (OR) between M23C6 carbide and matrix, we have determined a new OR named as the twin-related OR in a long-term ageing Ni-based superalloy on the basis of the extensive and detailed electron diffraction analyses. Furthermore, by means of atomic-resolution high angle annular dark-field imaging technique which is implemented in the aberration-corrected scanning transmission electron microscope, we elucidated the interfacial characteristics between M23C6 and matrix for above two types of ORs. Taking into account of the interfacial characteristics, we propose that the twin-related OR possesses a higher total interfacial energy. Thus, its frequency of occurrence is lower than that of the cube-on-cube OR though both ORs are usually seen in the long-term ageing samples. 相似文献
73.
How Do Employees Construe Their Career Success: An improved measure of subjective career success 下载免费PDF全文
Subjective career success has long been of interest to scholars because of its importance in the career area. However, the subjective career success literature suffers from the lack of measurement. To fill this void, after reviewing the limitations of the existing instruments, the current study developed a three‐dimensional scale of subjective career success based on the framework of Zhou et al. Three independent studies were conducted using three separate samples (N = 244; N = 411; N = 254) in China to examine the reliability and validity of the developmental scale. The results provided evidence of internal homogeneity, structural validity, convergent validity, discriminant validity, and incremental validity of the developed scale. To conclude the study, the limitations of the article and implications for future study were discussed. 相似文献
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75.
In a mental rotation task, participants must determine whether two stimuli match when one undergoes a rotation in 3-D space
relative to the other. The key evidence for mental rotation is the finding of a linear increase in response times as objects
are rotated farther apart. This signature increase in response times is also found in recognition of rotated objects, which
has led many theorists to postulate mental rotation as a key transformational procedure in object recognition. We compared
mental rotation and object recognition in tasks that used the same stimuli and presentation conditions and found that, whereas
mental rotation costs increased relatively linearly with rotation, object recognition costs increased only over small rotations.
Taken in conjunction with a recent brain imaging study, this dissociation in behavioral performance suggests that object recognition
is based on matching of image features rather than on 3-D mental transformations. 相似文献
76.
在我从教的数十年间,所教过的学生成百上千,赖宗贤先生可算得上是一个品德高尚、尊师重道、有诚挚的敬业精神、从不计较个人名利、热心致力于弘扬道教文化和积极促进海峡两岸学术交流、深受广大师生和同行学者们爱戴、敬仰的人。然而,正是他———我们敬爱的赖宗贤先生,却不幸过早地离开了我们。他逝世的噩耗,是今年春节刚过我在加拿大得到的,得知这一噩耗后,立即引起我无限的悲痛,马上便电告詹石窗教授代我送去挽联;在与遗体告别之日,又托李国梅博士代我送去花圈。虽然他离开我们而去了,但他的一些弘道事迹仍然一件件、一桩桩不断地浮现在… 相似文献
77.
Magnesium oxide (MgO) films and particles have been collected by pressurised filtration of a Mg-8.6wt%Al-0.67wt%Zn (AZ91D) alloy melt. The morphology of the oxides and their interfaces with the α-Mg phase were investigated by high-resolution transmission electron microscopy. It was found that the oxide films consisted of large numbers of sub-micrometre-sized MgO particles, and that melt shearing can effectively break up the oxide films and disperse the oxide particles. For the first time, orientation relationships (ORs) of OR I: [1?1?1]MgO~2° from (0?0?0?1)α-Mg and (0?1?1)MgO?//[2?1?1?0)α-Mg; and OR II: (1?1?1)MgO//(1?1?0?1)α-Mg and [0?1?1]MgO//[1?2?1?1]α-Mg, were observed between the MgO particles and the α-Mg matrix. The calculated Bramfitt planar disregistries were 5.5% and 2.5% for the two ORs, respectively, indicating good lattice matching between MgO and α-Mg at the interface. With the evidence of grain refinement effect observed in the sheared AZ91D magnesium alloy, the possibility of MgO particles to act as potent nucleants for heterogeneous nucleation of α-Mg grains is discussed in terms of the crystallographic criterion. 相似文献
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79.
Pedro Bezerra Shi Zhou Zachary Crowley Allan Davie Robert Baglin 《Journal of motor behavior》2013,45(5):413-421
It is known that electromyostimulation (EMS) alone or superimposed over voluntary contraction (EV) can effectively improve muscle strength. However, the effect of this type of training on the ability to control force production at submaximal levels is unknown. The authors examined the effects of EV training on steadiness in force production of knee extensors and flexors in older adults. Forty participants, including 20 men and 20 women, 60–77 years of age, were randomly allocated into a control group (CG) and an electromyostimulation superimposed over voluntary contraction (EVG) group. The EVG performed 30 bilateral isometric knee extension and flexion contractions per session, 3 training sessions per week, for 6 weeks. The variations in force production, expressed in absolute (standard deviation [SD]) and relative (coefficient of variation [CV]) terms, were assessed in isometric contractions at 5%, 15% and 25% maximal voluntary contraction (MVC) levels. Results indicated that MVC increased in knee extension and flexion in EVG (p < .05) after the training; steadiness CV also improved at 15% MVC in knee flexion (p < .05) but no significant changes were found in knee extension and steadiness SD. The training-induced changes in MVC were not correlated to steadiness CV that might indicate different mechanisms underlying these adaptations. 相似文献
80.
In this study, we examine when creativity is positively or negatively related to firm performance. Building on the creation–implementation tension theorized in the literature and the attention capacity perspective, we argue that the relationship between creativity and firm performance is contingent on riskiness orientation, firm size, and realized absorptive capacity. Data were collected from 761 core knowledge employees, 148 CEOs, and 148 HR executives from 148 high‐technology firms. The results indicated that core knowledge employee creativity was negatively related to firm performance when riskiness orientation was high. The relationship was positive when realized absorptive capacity was high. Finally, the relationship was more positive in small firms than in large firms. We discuss the implications of our findings for creativity research and managerial practices. 相似文献