首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   946篇
  免费   133篇
  国内免费   205篇
  2024年   4篇
  2023年   14篇
  2022年   31篇
  2021年   39篇
  2020年   31篇
  2019年   52篇
  2018年   46篇
  2017年   62篇
  2016年   52篇
  2015年   37篇
  2014年   38篇
  2013年   85篇
  2012年   61篇
  2011年   77篇
  2010年   73篇
  2009年   63篇
  2008年   60篇
  2007年   91篇
  2006年   83篇
  2005年   52篇
  2004年   42篇
  2003年   22篇
  2002年   24篇
  2001年   13篇
  2000年   22篇
  1999年   18篇
  1998年   14篇
  1997年   14篇
  1996年   4篇
  1995年   9篇
  1994年   2篇
  1993年   2篇
  1992年   8篇
  1991年   4篇
  1990年   7篇
  1989年   4篇
  1987年   1篇
  1986年   2篇
  1985年   1篇
  1984年   3篇
  1983年   3篇
  1982年   3篇
  1981年   8篇
  1980年   1篇
  1979年   2篇
排序方式: 共有1284条查询结果,搜索用时 31 毫秒
71.
高旭 《管子学刊》2013,(1):44-50
《淮南子》对墨子持有复杂的政治认识与态度,这在秦汉思想史上具有一定的代表性。从黄老道家的根本立场出发,“批墨”是《淮南子》政治思想的基本主张,但与此同时,《淮南子》也内在地显示出“尊墨”的政治情怀,进而试图对墨子政治思想有所借鉴和汲取,达到“融墨”之理论目的。对待墨子及其政治思想的历史态度,既凸显出《淮南子》立足黄老,融通诸子的博大精神,也彰显出墨子在秦汉政治思想发展中独特的历史影响。  相似文献   
72.
73.
This paper investigated how implicit and explicit knowledge is reflected in event-related potentials (ERPs) in sequence learning. ERPs were recorded during a serial reaction time task. The results showed that there were greater RT benefits for standard compared with deviant stimuli later than early on, indicating sequence learning. After training, more standard triplets were generated under inclusion than exclusion tests and more standard triplets under exclusion than chance level, indicating that participants acquired both explicit and implicit knowledge. However, deviant targets elicited enhanced N2 and P3 components for targets with explicit knowledge but a larger N2 effect for targets with implicit knowledge, revealing that implicit knowledge expresses itself in relatively early components (N2) and explicit knowledge in additional P3 components. The results help resolve current debate about the neural substrates supporting implicit and explicit learning.  相似文献   
74.
The primary purpose of this study was to investigate whether the theory of planned behavior (TPB) mediated the relationship between dialectical thinking and health behaviors. A sample of 285 undergraduates was tested with a dialectical thinking styles scale, health promoting lifestyle profiles, and TPB questionnaires. Structural equation modeling was used for data analysis. Results indicated that all the three dimensions of thinking styles (belief in the connection, acceptance of change, and acceptance of contradiction) exerted significant effects on TPB constructs. Specifically, the connection and the change dimensions had positive effects on health behaviors mediated by TPB, whereas the contradiction dimension had a negative effect. Model 2 showed a satisfactory fit, demonstrating the influential pathways between dialectical thinking and health behaviors. Implications in issues of health promotion and future research are discussed.  相似文献   
75.
Written emotional disclosure has been reported to confer a variety of benefits on physical and psychological well-being. However, variable findings suggest that outcomes may vary systematically as a function of specific parameters of the experimental design. This study aims to investigate the unique and combined effects of disclosure instructions focusing on emotional expression and instructions facilitating cognitive reappraisal and to examine how ambivalence over emotional expression and ethnicity moderate the effects of these writing instructions. Seventy-one Asian and 59 Caucasian undergraduates (N = 130) with at least minimal physical or depressive symptoms were randomly assigned to one of the four writing conditions: emotional disclosure (ED), cognitive reappraisal (COG), the combination of ED and COG, or a control condition. Self-reported physical symptoms, positive affect (PA) and negative affect were assessed at baseline and three follow-ups spanning 4 months. Mixed linear models revealed that COG writing reduced physical symptoms, ED buffered a decrease in PA over time, and the combination of ED and COG (i.e. self-regulation; SR) was most effective. Asians and highly ambivalent participants benefited most from expressive writing. Findings contribute to the development of a SR moderator model and carry implications for designing expressive disclosure studies, particularly for ethnic minorities.  相似文献   
76.
Electropulsing usually promotes a metastable phase to evolve towards its equilibrium state. This work reports an alternative case, where electropulsing promotes the decomposition of the stable δ-phase in duplex stainless steel at high temperature. This decomposition enables both the γ-phase and the σ-phase in the steel to survive and hence to strengthen it at high temperature. The hardness of the quenched sample with electropulsing treatment is 49.4% higher than that without electropulsing treatment. A fundamental understanding of the observation is developed.  相似文献   
77.
The crack-tip deformation behavior during a single overload, fatigue test of ferritic stainless steel, and Ni-based HAYNES 230 superalloy is studied at different structural levels using (1) neutron-diffraction, from which both the elastic-lattice strain and volume-averaged total dislocation densities are obtained, (2) polychromatic X-ray microdiffraction to probe the geometrically necessary dislocations and boundaries distribution, and (3) an irreversible and hysteretic cohesive interface model which has been implemented into a finite element framework to simulate the stress/strain evolution near the fatigue crack tip. Neutron strain measurements and finite element simulations are in qualitative agreement on the macroscopic length scale. Large plastic deformation induced by the overload and the resulting compressive residual strains are observed in front of the crack tip after the overload, and are the principal reason for the fatigue-crack-growth retardation. Strong strain gradients surrounding the crack propagation result in the formation of a high density of geometrically necessary dislocations near the fractured surface and cause local lattice rotations on the submicron level.  相似文献   
78.

La2 Zr2 O7 (LZO)-based pyrochlore islands were grown on a Y2 O3 -stabilized ZrO2 (YSZ) (001) single-crystal surface by the reaction between La2O3 vapour and the crystal. A network of interfacial edge dislocations with line directions [100] and [010] and Burgers vectors ( as/2)[101] and ( as/2)[011] respectively ( as being the lattice parameter of the YSZ) was observed at the moving LZO-YSZ reaction front. The interface-parallel component of the Burgers vectors accommodates the LZO-YSZ lattice mismatch of +5.0%, while the perpendicular component causes a slight tilt of the LZO lattice with respect to the YSZ lattice. The dislocation half-loops nucleate and glide on inclined {101} planes at the edges of the four corners of the growing islands.  相似文献   
79.
A key challenge in the fabrication of superhard nanocomposite films is how to control the distribution of grain sizes in these materials. High-resolution transmission electron microscopy has been used to measure nanograin-size distributions in the Ti–B–N films with various B contents. The results show that the mean grain size decreases with increase of B content and the grain-size distribution conforms to a log-normal function when the hardness approaches a maximum value. The transition from normal to log-normal distributions can be determined by analysis in terms of a minimum information criterion. The origin of a log-normal size distribution probably results from heterogeneity arising from a diffusion-drift process.  相似文献   
80.

Complete solid-state amorphization has been realized in elemental Se by means of mechanical milling of crystalline Se powder. Quantitative X-ray diffraction and thermal analyses were employed to characterize the amorphization process and indicated that the amorphization onset corresponds to a critical crystallite size and a drop in microstrain. During the major amorphization process, the remaining crystallite size remains unchanged with a constant lattice expansion. A new kinetics model of crystallite destabilization is proposed for the solid-state amorphization which satisfactorily explains the experimental observations.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号