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131.
Using high-resolution electron microscopy, we investigated the initial stages of high-pressure-torsion-induced crystalline-to-amorphous transformation of TiNi. It is found that the deformation-induced amorphization initiated from dislocation core regions in the interior of grains and from grain boundaries. It is believed that both the energy stored in the dislocations and the energy stored in the grain boundaries contribute significantly to driving the crystalline-to-amorphous transformation.  相似文献   
132.
The light yield of Y3+-doped PbWO4 crystals increases after low-dose-rate irradiation with?γ?rays, and the radiation hardness is sensitive to annealing temperature. In the PWO growth procedure, an excess of PbO in the starting materials is a convenient method of compensating for PbO volatility. The relationship between the excess of PbO and the abnormal radiation behaviour has been investigated. The mechanism of the normal excess of PbO in the growth of PWO: Y3+ is discussed.  相似文献   
133.
Research on the group-reference effect has confirmed that social identities can affect memory, but few studies have explored the role of identity salience in this effect. Two experiments were designed to fill the gap. In Experiment 1 Tibetan students at one predominantly Han Chinese university showed high ethnic identity salience and better memory for trait adjectives encoded in reference to Tibetans than in reference to Han Chinese. In Experiment 2 Tibetan students at one Tibetan-majority university demonstrated low ethnic identity salience and no differences were found between memory performance under Tibetan-referential processing and Han-referential processing conditions. In comparison, Han participants did not show high ethnic awareness or an ingroup-reference effect in either experiment, due to membership of an ethnic majority (Experiment1) and lack of inter-ethnic contact (Experiment 2). These findings suggest that high salience is a prerequisite for social identities to facilitate memory.  相似文献   
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This study addressed how engaging in different forms of information exchange within a group is related to group members' willingness to share risk information with outsiders. Drawing from social exchange theories, we focused on 3 unrestricted forms of information exchange: pure‐generalized, group‐generalized, and productive. We hypothesized that individuals' intentions to share information with outsiders would be associated positively with engagement in pure or group‐generalized exchanges and negatively with productive exchange. The hypotheses were supported with data from a national survey of U.S. growers (N = 452) that examined their information‐sharing behaviors with other parties inside and outside their local region. The findings have broad implications for understanding information sharing within and across groups.  相似文献   
136.
We examined whether perception of university environment mediated the association between minority status stress and college persistence attitudes after controlling for perceived general stress. Participants were 160 Asian American, African American, and Latino students who attended a predominantly White university. Results of a path model analysis showed that university environment was a significant mediator for the association between minority status stress and college persistence attitudes. Additionally, minority status stress was distinct from perceived general stress. Finally, the results from a multiple-group comparison indicated that the magnitude of the mediation effect was invariant across Asian American, African American, and Latino college students, thus supporting the generalizability of the mediation model.  相似文献   
137.
The present study investigated whether visual and kinesthetic stimuli are stored as multisensory or modality-specific representations in unimodal and crossmodal working memory tasks. To this end, angle-shaped movement trajectories were presented to 16 subjects in delayed matching-to-sample tasks either visually or kinesthetically during encoding and recognition. During the retention interval, a secondary visual or kinesthetic interference task was inserted either immediately or with a delay after encoding. The modality of the interference task interacted significantly with the encoding modality. After visual encoding, memory was more impaired by a visual than by a kinesthetic secondary task, while after kinesthetic encoding the pattern was reversed. The time when the secondary task had to be performed interacted with the encoding modality as well. For visual encoding, memory was more impaired, when the secondary task had to be performed at the beginning of the retention interval. In contrast, memory after kinesthetic encoding was more affected, when the secondary task was introduced later in the retention interval. The findings suggest that working memory traces are maintained in a modality-specific format characterized by distinct consolidation processes that take longer after kinesthetic than after visual encoding.  相似文献   
138.
《老子》首章在《老子》思想研究中有着举足轻重的地位,历代讨论的论作不胜枚举。但对《老子》首章的本义究竟如何解读,仍然是一个有待探讨的问题。下面,本文试对《老子》首章的各句逐一讨论,并对其主旨作一辨析。不妥之处,敬请批评。  相似文献   
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人在多项任务中的业绩及脑力负荷   总被引:5,自引:2,他引:3  
廖建桥 《心理学报》1995,28(4):356-362
在超脑力负荷状态下人的业绩是如何变化的?在实验中,让被试者同时完成四项内容不同的任务,即补偿追踪,选择反应,模拟雷达观察和算术运算。脑力负荷的强度是由改变工作的快慢节奏来实现的。实验的数据表明,随着脑力负荷的增加,人的业绩是逐渐下降的。在面对超负荷的多项任务时,人的信息处理过程更像一个单通道系统,集中精力完成某一工作,然后迅速地转移到下一个工作。  相似文献   
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