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71.
72.
A process is described for the fabrication of opal-like thin films by controlling a solid–liquid interface moving at an inclined glass substrate. A special airflow is adopted to control solvent evaporation. SEM images and photographs show that the films, composed of polystyrene spheres, are coloured, flat, uniform, packed multilayers, and are well arrayed over a large scale. The ordered domains range in size from 10 to 15?µm. The spheres in suspension crystallized, caused by an intense interaction between the spheres on the boundary between the suspension and the substrate. A wide photonic band gap is observed in the normal-incidence transmission spectra of the films fabricated by this method. Cracks and defects in the films are examined and discussed.  相似文献   
73.

Single-crystal 15R-SiC boules have been successfully grown by sublimation. The Vickers hardness of a Si-terminated (0001) face has been measured in the temperature range 25-1300C. As expected, the hardness decreases with increasing temperature from about 30GPa at room temperature to about 10GPa at 1300C. The fracture toughness is estimated to be about 1.0MPam 1/2 at room temperature. Transmission electron microscopy investigation of the dislocations introduced by indentation at 900 and 1300C shows that they are activated predominantly on the basal plane. Most of them consist of a single leading partial without the corresponding trailing partial.  相似文献   
74.
协作抑制是指当人们在一个记忆小组中一起提取信息的时候,小组提取的信息总量比等量个体提取的信息总量要少.心理学研究者致力于从认知角度对该现象进行解释,主要的理论解释有提取策略破坏假说和提取抑制假说.前者认为小组成员的提取结果对组内其他成员的信息组织策略产生了干扰,导致小组的提取成绩低.而后者认为小组内成员的提取结果会抑制其他成员对非提取项目的表征,降低小组协作提取能力,出现协作抑制.本文对两种理论假说的提出背景,基本观点,证据支持及现有争论进行了介绍,同时指出了未来的研究应关注于对两种机制的关键矛盾点进行区别性检验、对不同认知机制在不同条件下成立可靠性的检验以及通过对编码阶段进行操控来进一步考察协作抑制的认知机制.  相似文献   
75.
Flashing a homogeneous light mask after the presentation of a masked target reduces the deleterious effects of the mask, a phenomenon often called target recovery. Target recovery has been studied using masking paradigms in which a target object is presented in isolation prior to the presentation of a mask, thus capturing attention. In the present study, we examined whether target recovery is possible when a target does not benefit from attentional capture. We hypothesized that target recovery would be eliminated when a target must compete with distractors for perceptual attention. Replicating classic studies, we observed target recovery when pattern and light masks followed an isolated target. However, target recovery was not observed when a light mask followed a masked visual search target. Furthermore, using an attentional-capture paradigm we found that sudden onset search targets were recoverable whereas nononset targets were not. The present findings indicate that attentional capture by a target prior to masking plays a critical role in the subsequent recovery of the target.  相似文献   
76.
The present study examined the practice of forgiveness among participants from China (N = 172) and New Zealand (N = 91). We tested a theoretical model describing the relationships between collectivism, individualism, and forgiveness. Participants from China were more collectivistic and less individualistic than were participants from New Zealand. Overall, participants from New Zealand were more forgiving than were participants from China. Collectivism was positively related to decisional forgiveness in Chinese participants. Decisional forgiveness independently predicted conciliatory behaviour among participants from China, but this was not the case for participants from New Zealand. Thus, the hypothesized model received qualified support.  相似文献   
77.
Although attentional biases toward body-related information contribute to the etiology and maintenance of body dissatisfaction (BD) and eating disorders (EDs), attentional disengagement in women with BD and EDs is not clear. The present study investigated the association between weight dissatisfaction and attentional disengagement from body-related pictures and the possible moderating effect of body mass index (BMI) on this relation. Two hundred and four undergraduate women engaged in an experiment using a pictorial spatial cueing paradigm including fat/thin bodies and neutral household photos. Partial correlations and simple slopes regression analyses were conducted with attentional disengagement index scores of each category of cues. Findings suggested that independent of BMI, weight dissatisfaction was directly associated with attentional disengagement from both fat and thin pictures. In addition, among women with low and medium BMIs, the more they were dissatisfied with their bodyweight, the more difficulty they had disengaging their attention from fat body pictures.  相似文献   
78.
Various demonstrations of “time stamp” effects in the animal learning literature have reinforced the idea that circadian information is encoded as part of a combined internal/external representation of context and that this contextual information is utilized for complex retrieval processes supporting memory. The goal of the present series of experiments is to assess this idea by manipulating training/testing circadian times on a battery of learning and memory tasks commonly used in the rodent. The data obtained from five experiments using four different learning and memory paradigms provide no evidence for “time stamp” effects on place memory, context memory (aversive or appetitive), or S-R habit learning.  相似文献   
79.
创造性的生理研究新进展   总被引:7,自引:0,他引:7  
创造性的生理基础很复杂。关于创造性生理基础的研究集中在大脑皮质激活与脑半球不对称两个方面。研究发现,大脑皮质激活状态对创造性有影响,低水平的皮质激活,特别是低水平的前额叶激活,较有利于创造性.研究还发现,创造性和左右半球不对称活动有关,处于创造状态时,右半球相对要比左半球激活程度更高。  相似文献   
80.
三论宗是以龙树的《中论》、《十二门论》和提婆的《百论》为所依,宣扬空、无相、八不中道等义理的宗派。由姚秦时罗什传来的三论学,谓古三论;而由僧朗、僧诠、吉藏所传的三论学,称为新三论。新、古之分,不仅因其在传承和时间上,就是在产生的背景、思想和影响上均有差别。  相似文献   
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