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141.
We examined predictors of media multitasking in Chinese adolescents from 3 contexts: characteristics of the media user, types of media use and family media contexts. Three hundred and twenty adolescents, 11–18 years of age, completed questionnaires to measure media use, impulsivity, sensation seeking, time management disposition and family media environment. The results showed that media multitasking was positively correlated with age and total media use time. Participants with high levels of impulsivity and sensation seeking reported more multitasking behaviour. Multitasking was negatively correlated with time management. Children from media‐oriented families often engage in more multitasking. What's more, social networking sites use and music use can mediate the effect of individual and family factors on media multitasking.  相似文献   
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143.
We evaluated the usefulness of 2 assessments to guide treatment selection for individuals whose prior functional analysis indicated that automatic reinforcement maintained their problem behavior. In the 1st assessment, we compared levels of problem behavior during a noncontingent play condition and an alone or ignore condition. In the 2nd, we assessed participants’ relative preferences for automatic reinforcement and social reinforcers in a concurrent‐operants arrangement. We used the results of these 2 assessments to assign 5 participants to a treatment based on noncontingent access to social reinforcers or to a treatment based on differential access to social reinforcers. We conducted monthly probes with the participants over 10 to 12 months to evaluate the effects of the treatment procedures. All participants showed reductions in problem behavior over this period.  相似文献   
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145.
What roles do CEOs play in firm performance? To address this question, the management field has accumulated a substantial amount of research over the past 3 decades built on upper echelons theory (UET), which posits that CEO characteristics manifest in firm strategic actions and, in this way, future firm performance. Hence, there is a need to systematically amass and take stock of prior empirical findings for UET testing and development. We use meta‐analytic techniques to synthesize prior UET research on the relationships among commonly studied CEO characteristics, firm strategic actions, and future firm performance. Based on 308 studies, meta‐analytic results generally support UET's predictions with a few exceptions: CEO characteristics (i.e., tenure, formal education, prior career experience, and positive self‐concept) are significantly associated with firm strategic actions, which in turn are significantly related to future firm performance. Moreover, CEO characteristics (i.e., age, tenure, formal education, and prior career experience) are positively related to future firm performance. In addition, fine‐grained analyses have revealed interesting and important relationships between specific measures of CEO characteristics (e.g., CEO prior task experience) and firm outcomes (e.g., firm strategic actions that match with CEO prior task experience). Implications for theory, future research, and practice are discussed.  相似文献   
146.
Research on early false belief understanding has entirely relied on affect‐neutral measures such as judgments (standard tasks), attentional allocation (looking duration, preferential looking, anticipatory looking), or active intervention. We used a novel, affective measure to test whether preschoolers affectively anticipate another's misguided acts. In two experiments, 3‐year‐olds showed more expressions of suspense (by, e.g. brow furrowing or lip biting) when they saw an agent approach a scene with a false as opposed to a true belief (Experiment 1) or ignorance (Experiment 2). This shows that the children anticipated the agent's surprise and disappointment when encountering reality. The findings suggest that early implicit knowledge of false beliefs includes anticipations of the affective implications of erring. This vital dimension of beliefs should no longer be ignored in research on early theory of mind.  相似文献   
147.
Crack networks and residual tensile stresses are general characteristics of electrodeposited hard chromium coatings. In this paper, crack-free hard chromium coatings with compressive stresses have been obtained by an electrodeposition process assisted by abrasive polishing. The deposited coatings had mirror-like smooth surfaces, values of hardness in the range 800–1000 HV and compressive stresses between 1000 and 1600 MPa. A model involving hydrogen disentanglement from the lattice is proposed to explain the effects of abrasive polishing on the complete elimination of cracks and the generation of a compressive stress. This explanation is discussed in terms of the variations in properties of the coating with the rotation speed of the cathode.  相似文献   
148.
Based on the well-accepted physical understanding that cleavage fracture of structural steels is preceded by plastic deformation, a critical flaw in the Beremin model and its modifications is proposed, and a new statistical model with the power-law distribution of microcracks is obtained to describe the cumulative probability of cleavage fracture. A set of cleavage fracture toughness data of a nuclear pressure vessel steel is used to highlight the difference between the new model and the Beremin model.  相似文献   
149.
本研究探讨文章阅读过程中结构因素对文章信息保持的影响作用。包括两个实验。实验 1探讨阅读文章结构是否清晰及主体对文章结构是否有清晰的把握对文章信息保持的影响效果。结果表明 ,阅读的文章结构越清晰 ,主体对文章结构把握能力越强 ,越能促进文章的信息保持。实验 2进一步探讨文章的结构清晰及主体对文章结构的清晰把握促进的是何种信息的保持。结果证明 ,结构清晰与否促进的是文章的主要信息的保持 ,而对文章的细节性信息促进作用不大。本研究结果表明 ,文章的结构因素对阅读保持有促进作用 ,主要是促进文章的主要信息的保持。  相似文献   
150.
文章标记量影响文章标记效应的实验研究   总被引:3,自引:0,他引:3  
探讨文章阅读过程中文章标记量的多少对文章中不同类型的信号保持的影响。结果表明 ,在有标记的目标句上 ,少标记条件显著优于多标记条件和无标记条件 ,多标记条件与无标记条件之间无显著差异 ;在无标记的目标句上 ,无标记条件显著优于多标记条件和少标记条件 ,多标记条件与少标记条件之间无显著差异。这一结果支持在文章阅读过程中读者是微略性地运用文章标记的假设和交易效应的假设。  相似文献   
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