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601.
Sai-Yan Chen Xue-Li Cao Meng-Rou Huang Dong-Hui Liang 《Philosophical Magazine Letters》2013,93(8):292-301
ABSTRACTWe have theoretically investigated the control of wave-vector filtering (WVF) by introducing δ-doping into a magnetically modulated nanostructure fabricated by depositing ferromagnetic stripes on top and bottom of a GaAs/AlxGa1 ?xAs heterostructure. With the help of an improved transfer matrix method, the Schrödinger equation for electrons in this semiconductor nanostructure is solved exactly and the transmission efficient calculated numerically. We demonstrate that the WVF efficiency is associated closely with the weight and position of the δ-doping, which may be helpful for designing a controllable electron-momentum filter based on such a magnetically modulated semiconductor nanostructure. 相似文献
602.
H. Wei J.J. Liang P. Peng Q. Zheng X.F. Sun B.Z. Sun 《Philosophical Magazine Letters》2013,93(5):299-311
The valence band structures of the NiAl–Mo alloy was investigated by photoelectron spectroscopy. The valence band spectra of the NiAl–Mo alloy was shifted away from the Fermi level so that the Ni-d-band centroid moved to a higher energy by 0.22 eV as Mo was added. A possible explanation lied in the overlap of Ni-d bands in the energy with Mo-d and Al-p bands. The participation of Mo-d bands was correlated with the site preference of Mo in NiAl alloys. 相似文献
603.
Xuechen Ding Murray Weeks Junsheng Liu Biao Sang Ying Zhou 《Infant and child development》2015,24(1):94-103
Unsociable children are likely to develop adjustment difficulties in Chinese society. The primary goal of the present study was to examine the moderating effect of behavioural control on the relation between unsociability and peer problems in Chinese children. Participants were fourth to eighth grade students in urban China (N = 787). Assessments of unsociability, shyness, peer problems and behavioural control were obtained from peer nominations and teacher ratings. Results indicated that unsociability was positively related to peer problems in Chinese children after controlling for shyness. Also, the relation between unsociability and peer problems was attenuated among children with higher behavioural control. Thus, behavioural control may be a buffering factor that serves to protect unsociable children from developing peer problems. Gender and age also moderated these associations. Results are discussed in terms of the meaning and implications of unsociability and behavioural control in Chinese culture. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
604.
Wai‐Yung Lee Shin‐Ichi Nakamura Moon Ja Chung Young Ju Chun Meng Fu Shu‐Chuan Liang Cui‐Lian Liu 《Family process》2013,52(3):499-518
The purpose of this study was to explore variations in how contemporary couples from five different Asian regions negotiate disagreements. Video recordings of 50 couples (10 each from Japan, Korea, Mainland China, Taiwan, and Hong Kong) discussing unresolved disagreements provided raw data for quantitative and qualitative analyses. First, teams of coders from each region used a common protocol to make quantitative ratings of content themes and interaction patterns for couples from their own region. An interregional panel of investigators then performed in‐depth qualitative reviews for half of these cases, noting cultural differences not only in observed patterns of couple behavior but also in their own perceptions of these patterns. Both quantitative and qualitative analyses revealed clear regional differences on dimensions such as overt negativity, demand‐withdraw interaction, and collaboration. The qualitative results also provided a richer, more nuanced view of other (e.g., gender‐linked) conflict management patterns that the quantitative analyses did not capture. Inconsistencies between qualitative and quantitative data and between the qualitative observations of investigators from different regions were most pronounced for couples from Korea and Japan, whose conflict styles were subtler and less direct than those of couples from the other regions. 相似文献
605.
Feifei Liang Hazel I. Blythe Chuanli Zang Xuejun Bai Guoli Yan 《Journal of Cognitive Psychology》2015,27(5):594-608
Children's eye movements were recorded to examine the role of word spacing and positional character frequency on the process of Chinese lexical acquisition during reading. Three types of two-character novel pseudowords were constructed: words containing characters in positions in which they frequently occurred (congruent), words containing characters in positions they do not frequently occur in (incongruent) and words containing characters that do not have a strong position bias (balanced). There were two phases within the experiment, a learning phase and a test phase. There were also two learning groups: half the children read sentences in a word-spaced format and the other half read the sentences in an unspaced format during the learning phase. All the participants read normal, unspaced text at test. A benefit of word spacing was observed in the learning phase, but not at test. Also, facilitatory effects of positional character congruency were found both in the learning and test phase; however, this benefit was greatly reduced at test. Furthermore, we did not find any interaction between word spacing and positional character frequencies, indicating that these two types of cues affect lexical acquisition independently. With respect to theoretical accounts of lexical acquisition, we argue that word spacing might facilitate the very earliest stages of word learning by clearly demarking word boundary locations. In contrast, we argue that characters' positional frequencies might affect relatively later stages of word learning. 相似文献
606.
The purpose of this study was twofold: (1) to analyze the effects of both personality and environmental variables on the imagination of video/film major university students; and (2) to test the mediator effect resulting from the variable of social climate. The results of this study supported both indicators of imaginative capabilities and environmental influences. The hypothesis of the study—that the variable of social climate mediates the effects of personality/environmental predictors and both types of imagination—was partially supported. The structural model also showed that most personality traits have direct effects on imagination, whereas most environmental predictors have indirect effects. Practical applications of this study were suggested, future inquiries were discussed, and limitations were acknowledged. 相似文献
607.
近年来许多行为实验和神经生理学实验都发现 ,发展性阅读障碍与基本知觉障碍有关。在视觉领域研究者提出了巨细胞障碍假设 ,这种假设认为阅读障碍者视觉神经系统中的巨细胞障碍导致他们对某种类型的视觉刺激加工存在困难 ,进而影响阅读。在听觉领域研究发现阅读障碍者加工快速、系列、短暂呈现的声音刺激存在障碍。研究者认为阅读障碍者加工快速刺激输入障碍反映了普遍的时间知觉障碍。这方面的研究发展非常迅速 ,理论观点非常明确 ,并且直接与内在的神经机制相联系 ,形成了与传统的“语言障碍”理论迥然不同的“知觉障碍”理论。“知觉障碍”理论综合了行为、认知和神经等多个层次的研究 ,反映了神经科学发展所带来的巨大影响和认知加工模块化理论的渐渐衰退。 相似文献
608.
为揭示任务切换中切换代价的本质, 考察了预先信息与准备时间对任务切换的影响, 结果发现: (1) 预先信息对任务切换有显著的影响效应, 全部信息的反应时和切换代价显著低于无信息和部分信息的反应时和切换代价, 而后二者之间无显著差异; (2) 预先信息的影响效应受到准备时间的调节作用, 在准备时间为100ms时, 预先信息无显著的影响效应, 而在准备时间达到600ms以后, 预先信息的准备效应显著。这说明, 预先信息影响的认知加工是任务设置重构, 并且这种影响效应受到准备时间的调节作用。 相似文献
609.
610.