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661.
The γ/γ′ interfaces are thought to play an important role in determining the mechanical properties in single-crystal nickel-based superalloys. In this article, interfacial width in DD6, one second-generation single-crystal superalloy containing 2 wt% Re, has been studied by means of scanning transmission electron microscopy. From an atomic resolution high angle annular dark field image, both compositional interfaces and order–disorder interfaces are studied, and it is first found that the interfacial width of chemical composition is same with that between the ordered and disordered phases.  相似文献   
662.
The strengthening of the β phase in two fully lamellar structures with different lamellar spacing of a Ti–48?at.%?Al–2?W?at.% alloy during creep deformation has been investigated. It was found that the β phase precipitates during aging treatments only within regions of α2 lamellae following their dissolution. The strengthening of the β phase is more effective in the coarser lamellar structure, because the wider β precipitation zones, which replace the prior coarser α2 lamellae, hinders dislocation motion stronger than the narrower ones.  相似文献   
663.
We demonstrated unconscious learning of task-irrelevant perceptual regularities in a Serial Reaction Time (SRT) task in both visual and auditory domains. Participants were required to respond to different letters (‘F’ or ‘J’, experiment 1) or syllables (‘can’ or ‘you’, experiment 2) which occurred in random order. Unbeknownst to participants, the color (red, green, blue or yellow) of the two letters or the tone (1–4) of the syllables varied according to certain rules. Reaction times indicated that people indeed learnt both the color and tonal regularities indicating that task-irrelevant sequence structure can be learned perceptually. In a subsequent prediction test of knowledge of the color or tonal cues using subjective measures, we showed that people could acquire task irrelevant knowledge unconsciously.  相似文献   
664.
本研究采用实验和问卷相结合的方法,探讨了愤怒和恐惧情绪及不同的方案数量对危机决策的影响,并分析了该效应的性别差异。研究结果表明:(1)恐惧情绪下被试的危机决策时间显著长于其在愤怒情绪下的危机决策时间,且情绪和性别变量在危机决策时间上存在显著的交互作用;(2)女性在恐惧情绪下的危机决策时间显著长于其在愤怒情绪下的危机决策时间,且显著地长于男性的危机决策时间。同时,男性对其危机决策的满意程度显著高于女性,且情绪变量和性别变量在危机决策自信程度指标上存在显著的交互作用;(3)随着方案数量的增加,尤其当方案数量为4时,被试的危机决策时间较其他两种情况显著增长。该研究结果可为各类突发性危机事件的管理与决策提供依据。  相似文献   
665.
旨在探讨不同刺激重复量对反应抑制后效应的影响。在不同刺激重复量条件下,让被试完成停止信号任务。结果发现,从总体来看,刺激重复量因素上的主效应显著,重复类型因素上主效应不显著;信号抑制条件下不同刺激重复量后无信号试次反应时与总的无信号试次反应时差异不显著;信号反应条件下不同刺激重复量后无信号试次反应时与总的无信号试次反应时差异显著。本研究表明不同刺激重复量条件下的反应抑制后效应是认知控制的执行加工而非自动化的记忆提取。  相似文献   
666.
Nongovernmental organizations (NGOs) serve Iraqis living in Jordan as “guests.” In 2008, 258 Jordanian humanitarian staff and Iraqi volunteers working for NGOs completed a needs assessment survey. Work characteristics, stressors, and support variables were evaluated regarding their influence on depression, anxiety, post-traumatic stress disorder (PTSD), and burnout through multivariate logistic regressions. There was a significant difference in depression, anxiety, and burnout across nationality. Traumatic exposure increased the risk for anxiety, depression, and PTSD. Working longer in the humanitarian sector was associated with less risk of anxiety and depression, and lower social support was a risk for anxiety. Managers were at higher risk for burnout, and low team cohesion was a risk for burnout. Implications for aid organizations are discussed.  相似文献   
667.
Four-, five-, and six-year-old Chinese and Canadian boys and girls were presented a series of 11 graphic models and were asked to draw them. Supporting Piaget's theory, the data indicated that drawing performance on the topological dimension was better than the performance on the Euclidean dimension, and that there were neither gender nor cultural differences in performance. The research offers strong support for a main effect of biological or maturational factors as the foundation for the developmental influences in the acquisition of spatial conceptions.  相似文献   
668.
More attention is being given to the stable, dispositional tendency to maximize when making decisions. Within the growing body of research has been an exchange regarding the appropriate means of measuring maximizing tendency. Guided primarily by psychometric and statistical analyses, these studies have critiqued and revised existing maximizing tendency scales and/or introduced new measures. Importantly, many of these discussions seem to ignore theoretical considerations of the construct of maximizing. In this article, we revisit the original work of Herbert Simon, from where the theory of maximizing tendency was developed, and provide a theoretical account for how maximizers can be distinguished from satisficers and the implications therein for the measurement of maximizing tendency. Across two studies, we provide an updated psychometric, correlational, and behavioral comparison of the two most popular maximizing tendency scales: the Maximization Scale and the Maximizing Tendency Scale. Results demonstrate that the Maximizing Tendency Scale is more theoretically and psychometrically valid than the Maximization Scale. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
669.
何睿  朱菁 《逻辑学研究》2015,(2):98-113
心智架构或认知架构是指一个功能相对完整的认知系统的基本组织结构。经典认知科学的理论或模型大多采纳了某种类似于冯·诺依曼式计算机体系结构的心智架构,即认知系统由一些各司其职的心理模块与一个负责整合与协调的中枢部门所构成。进化心理学的众量模块性论题对经典认知科学的心智架构观提出了严厉挑战,并引发了许多争议。本文提出认知冲突协调问题是任何一个足够复杂的认知系统均需要处理的基本问题,并以此来审视关于心智架构的论战,指出此问题对众量模块性论题构成了严重的困难。  相似文献   
670.
Schools typically ignore an enormous part of students’ learning, i.e. informal learning. Such informal processes include intentional, incidental, and tacit learning and tend to be unnoticed because of their taken-for-granted nature. By conducting in-depth interviews with 15 students, two teachers, and two program coordinators of an adult education program, this study examines informal learning outcomes, processes, and personal informal learning experiences within formal education. The study aimed to reveal the interaction between formal and informal learning as well as the respondents’ experiences in this matter. Respondents report a diverse array of informal learning results. Respondents describe informal learning to occur through self-directed learning projects, daily conversations and experiences, and the program’s informal and hidden curriculum. According to respondents, informal learning has the potential to enrich and complement formal learning. Moreover, the findings point to potential personal, educational, and societal benefits of revealing informal learning within formal education. Implications for practice and future research are discussed.  相似文献   
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