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121.
In this study, (Gd1? x Nd x )2(Zr1? x Ce x )2O7 (0 ≤ x ≤ 0.5) ceramics have been prepared by pressureless sintering at 1973 K to investigate the influence of Nd and Ce co-doping on their electrical conductivity. The electrical conductivity of the ceramics was investigated by impedance spectroscopy measurements from 723 to 1173 K over the frequency range of 20 Hz to 2 MHz in air. The measured values obey the Arrhenius relation. For each composition, the grain conductivity gradually increases with increasing temperature from 723 to 1173 K. At a given temperature, it gradually decreases with increasing neodymium and cerium contents from x = 0 to 0.3; thereafter, the grain conductivity exhibits a slight increase with further increasing neodymium and cerium contents up to x = 0.5.  相似文献   
122.
ABSTRACT

Recently a novel type of epithelial cell has been discovered and dubbed the ‘scutoid’. It is induced by curvature of the bounding surfaces. We show by simulations and experiments that such cells are to be found in a dry foam subjected to this boundary condition.  相似文献   
123.

The thermal stability of highly disordered mechanically alloyed nanocrystalline NiAl has been evaluated. The reordering of disordered NiAl(Cr) shows extremely fast kinetics on isothermal annealing at and above 673K, while the process is quite sluggish below this temperature. On the other hand, significant reordering in NiAl(Fe) takes place even at 573K. A unique dependence of reordering on the grain growth of the nanophase is evident during thermal treatment. Rapid grain coarsening begins only as the absolute temperature approaches approximately 0.4 T m, where T m is the melting point of the aluminide.  相似文献   
124.
When people think about how a situation might have turned out differently, they tend to imagine counterfactual alternatives to their actions. We report the results of three experiments which show that people imagine alternatives to actions differently when they know about a reason for the action. The first experiment (n = 36) compared reason – action sequences to cause – effect sequences. It showed that people do not imagine alternatives to reasons in the way they imagine alternatives to causes: they imagine an alternative to an action more than an effect, and to a cause more than a reason. The second experiment (n = 214) and the third experiment (n = 190) both show that different sorts of reasons have different sorts of effects on how people imagine alternatives to actions. People imagine an alternative to an action (the protagonist went to a ball) less often when they know the reason for the action was an obligation (he had to participate in fundraising) compared to when they know about a weaker reason (he wanted to meet a famous violinist) or no reason. The second experiment shows the effect for a social obligation and the third experiment replicates and extends it to a health obligation. We interpret the results in terms of the possibilities that people keep in mind about actions and their reasons.  相似文献   
125.
Wason's standard 2-4-6 task requires discovery of a single rule and leads to around 20% solutions, whereas the dual goal (DG) version requires discovery of two rules and elevates solutions to over 60%. We report an experiment that aimed to discriminate between competing accounts of DG facilitation by manipulating the degree of complementarity between the to-be-discovered rules. Results indicated that perfect rule complementarity is not essential for task success, thereby undermining a key tenet of the goal complementarity account of DG facilitation. The triple heterogeneity account received a good degree of support since more varied triple exploration was associated with facilitatory DG conditions, in line with this account's prediction that task success is associated with the creative search of the problem space. The contrast class account (an extension of Oaksford & Chater's, 1994, iterative counterfactual model) was also corroborated in that the generation of descending triples was demonstrated to be the dominant predictor of DG success. We focus our discussion on conceptual ideas relating to the way in which iterative counterfactual testing and contrast class identification may work together to provide a powerful basis for effective hypothesis testing.  相似文献   
126.
The present study examined whether organizational justice moderates the association of shift work and employment type with patient-related stress, stress symptoms, and musculoskeletal symptoms. Cross-sectional survey data from 1270 Finnish female elderly care staff aged 18–69 years was used. Analyses of covariance were used to examine the associations adjusted for age,marital status, education, and tenure. Organizational justice was associated with lower levels of patient-related stress, stress symptoms, and musculoskeletal symptoms. Organizational justice mitigated stress symptoms related to working night shift and three shifts. In addition, organizational justice mitigated the patient-related stress associated with working on fixed-term contracts. Organizational justice was also able to alleviate musculoskeletal symptoms associated with working on permanent contracts. Thus, we found evidence for organizational justice being able to mitigate the negative effects of shift work and employment type. Promoting organizational justice in organizations with shift work and lots of fixed-term contracts is of importance.  相似文献   
127.
The primary objective was to compare the MMPI-2 profiles for professional job applicants with corresponding profiles on the original MMPI. Male and female MMPI-2 profiles were also compared, and correlational and factor analyses were used to examine: A) Interscale correlations vis-à-vis item overlap, and B) The impact of K-corrections. The subjects were 82 auditor applicants, plus 212 sales and management applicants from an earlier study. The original MMPI was found to overpathologize applicant profiles. Male and female MMPI-2 profiles differed only on Mf. Scales L, K, and Hy formed a favorable cluster for job applicants, while F, Hs, Pt, Sc formed one unfavorable cluster—and D, Si a second. K-corrections consistently moved clinical scales in the direction of the favorable cluster.  相似文献   
128.
以2岁儿童为被试,探讨其在延迟满足情境中的自我控制能力发展的状况。结果表明:(1)2岁儿童已具有一定程度的自我控制能力,个体差异显著,性别差异不显著;(2)2岁儿童已能使用一定的延迟策略,包括问题解决、分心、寻求安慰、消极等待、寻求他人帮助、回避等,其中使用频率最高的是分心策略;(3)不同的策略对延迟时间有着不同的影响;(4)儿童对策略的使用不会因延迟满足情境的不同而出现显著差异。  相似文献   
129.
在押毒品犯人格的基本特征及其相关因素的研究   总被引:3,自引:0,他引:3  
本研究以 3 78名在押毒品犯为被试 ,以CPI为测量工具 ,探讨了在押毒品犯的基本特征和类型特征 ,并采用方差分析技术研究了影响毒品犯人格的若干因素。结果发现 ,与对照组相比 ,在押毒品犯除了在“自我控制”分量表上未发现显著差异外 ,其余的 1 9个分量表上均有显著差异 ;在押毒品犯在四种人格类型上的分布不平衡 ,主要集中在Delta类型 ;年龄、关押时间对毒品犯的人格特征的变异有一定影响 ,而减刑次数的影响不显著  相似文献   
130.
声旁类型与频率在汉字和部件识别中的交互作用   总被引:1,自引:0,他引:1  
杨利利  韩布新 《心理科学》2002,25(2):180-183
用识别整字和识别部件两种任务探讨两种声旁频率——组字频率和使用频率的作用。结果发现:在局部识别中声旁使用频率的影响和部件类型有交互作用。声旁使用频率对识别汉字单部件声旁有易化作用。声旁组字频率的影响和部件类型有交互作用。声旁组字频率对识别汉字多部件组合声旁有易化作用。在整字识别中,声旁的使用频率有易化作用;声旁的组字频率的作用受到部件类型的影响,多部件组合声旁的组字频率对识别整字有易化作用。  相似文献   
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