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111.
Hao Chen Wei Xu Mohamed Goune Sybrand van der Zwaag 《Philosophical Magazine Letters》2013,93(10):547-555
The length of the stagnant stage during the new ferrite growth starting from a mixture of austenite and ferrite has been investigated for a Fe-0.17Mn-0.023C (wt%) alloy. It was found that the stagnant stage depends on the thermal path followed to create the mixture, and deduce that the tie-lines for austenite to ferrite transformation are quite different from those for ferrite to austenite transformation. The length of the stagnant stage is determined by the very local partitioning effect at the interface, and it can be used as a tool to monitor the Mn partitioning. 相似文献
112.
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
113.
知情同意作为生命伦理的重要原则,在基因研究中同样占据重要的地位,由于基因研究中知情同意的异质性,在基因研究中面临着诸如如何理解其知情同意的异质性、群体知情同意、基因知情与基因隐私、利益冲突等问题.通过分析基因研究中知情同意的特殊性,综合国内外此领域的已有研究,运用理论联系实际的方法,得出结论认为,只有正确区分基因知情与基因隐私的权利主体,用伦理规范来解决利益冲突,在发展中不断完善知情同意,才能够取得科技与伦理的共赢. 相似文献
114.
肥胖是体内脂质过度沉积的一种状态,其不仅可引起糖脂代谢紊乱、胰岛素抵抗,从而继发糖尿病、高血压、冠心病等疾病,而且当脂质水平超过脂肪细胞的储存容量及出现胰岛素抵抗时,血液中游离脂肪酸含量会随之升高,进而可引起脂质在心脏的异位沉积.沉积于心肌细胞的脂质可进一步通过神经酰胺、内质网应激等机制影响心肌细胞的结构和功能,最终导致心力衰竭的发生.但肥胖所致心肌脂毒性具体机制不明,本文就肥胖所致心肌脂毒性可能机制做一综述. 相似文献
115.
《淮南子》对墨子持有复杂的政治认识与态度,这在秦汉思想史上具有一定的代表性。从黄老道家的根本立场出发,“批墨”是《淮南子》政治思想的基本主张,但与此同时,《淮南子》也内在地显示出“尊墨”的政治情怀,进而试图对墨子政治思想有所借鉴和汲取,达到“融墨”之理论目的。对待墨子及其政治思想的历史态度,既凸显出《淮南子》立足黄老,融通诸子的博大精神,也彰显出墨子在秦汉政治思想发展中独特的历史影响。 相似文献
116.
117.
The primary purpose of this study was to investigate whether the theory of planned behavior (TPB) mediated the relationship between dialectical thinking and health behaviors. A sample of 285 undergraduates was tested with a dialectical thinking styles scale, health promoting lifestyle profiles, and TPB questionnaires. Structural equation modeling was used for data analysis. Results indicated that all the three dimensions of thinking styles (belief in the connection, acceptance of change, and acceptance of contradiction) exerted significant effects on TPB constructs. Specifically, the connection and the change dimensions had positive effects on health behaviors mediated by TPB, whereas the contradiction dimension had a negative effect. Model 2 showed a satisfactory fit, demonstrating the influential pathways between dialectical thinking and health behaviors. Implications in issues of health promotion and future research are discussed. 相似文献
118.
Xue Du Yigui Qin Shen Tu Huazhan Yin Ting Wang Caiyun Yu Jiang Qiu 《International journal of psychology》2013,48(2):149-157
This study aimed to investigate the mechanisms underlying joke comprehension using event‐related potentials (ERPs). Fourteen healthy college students were presented with the context of a story without its joke or nonjoke ending, and then, when the story ending was presented, they were asked to make a funny/unfunny judgment about these endings. The behavioral results showed that there was no significant difference between funny and unfunny items, which meant that subjects could understand funny items as easily as unfunny ones. However, the ERP results showed that funny items initially elicited a more negative ERP deflection (N350–450) over frontocentral scalp regions. Dipole analysis localized the generators in the left temporal gyrus and the left medial frontal gyrus; it is suggested that these areas might be involved in detecting the incongruent element in joke comprehension. Between 600 and 800 ms, funny items subsequently elicited a more negative ERP deflection (N600–800) over frontocentral scalp regions and a more positive ERP deflection (P600–800) over posterior scalp regions. Dipole analysis localized the generator in the anterior cingulate cortex (ACC), an area involved in the breaking of mental set/expectation and the forming of novel associations. Finally, funny items elicited a more positive ERP deflection (P1250–1400) over anterior and posterior scalp regions. Dipole analysis localized the generators in the middle frontal gyrus and the fusiform gyrus, areas that might be related to the affective appreciation stage in joke process. Unlike that of Coulson and Kutas (2001), the present study might support the hypothesis of a three stage model of humor processing (humor detection, resolution of incongruity and humor appreciation). 相似文献
119.
This study tested the greater male variability hypothesis in creative thinking with a Chinese student sample in Mainland China. The Test for Creative Thinking-Drawing Production (TCT-DP) was administered to 627 Chinese adolescent boys (n = 332) and girls (n = 295). Results using the boy/girl variance ratio (VR) generally supported the hypothesis that boys have greater variability than girls in creativity test performance. However, results using the boy/girl ratios from different regions of the creativity score distribution revealed a pattern of male superiority. While boys significantly outnumbered girls in the higher extremes, girls tended to outnumber boys in the central region and the lower extremes. Results from an analysis of the means lent further support to the findings of male superiority. Plausible explanations for greater male variability and male superiority in Mainland China are proposed. The theoretical and practical implications of the findings are discussed. 相似文献
120.
Ming Xu 《Studia Logica》2013,101(3):583-599
This paper proves the finite model property and the finite axiomatizability of a class of normal modal logics extending K4.3. The frames for these logics are those for K4.3, in each of which every point has a bounded number of irreflexive successors if it is after an infinite ascending chain of (not necessarily distinct) points. 相似文献