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191.
Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO2 and the inner layer a mixture of TiO and Ti2O. The thickness of the Ti2O, TiO and anatase-TiO2 were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti2O to tetragonal TiO2 phase transformation rate induced by the substitution of Li+ for Ti4+ in the oxide layer.  相似文献   
192.
The compressive deformation and fracture features of Zr59Cu20Al10Ni8Ti3 bulk metallic glassy samples with aspect ratios in the range of 0.67–2.00 have been investigated. The compressive plastic strain of the glass monotonically increases with decreasing aspect ratio, but the maximum strength almost maintains a constant value of 1.77–1.88?GPa. All the compressive shear-band angles are equal to?~40° if modified by the rotation of the primary shear bands.  相似文献   
193.
194.
The grain size variation in a gradient surface produced by a punching and recovery process on a Cu-30Ni alloy has been observed by atomic force microscopy. The friction characteristics of the gradient surface in a 3.5 wt% NaCl solution were investigated using a micro-indenter probe, a pin-on-disc type tribometer, a strain sensor and an optical microscope. The results showed that the hardness and grain size can be well represented by the Hall–Petch relationship when the gain size is more than 30?nm. The wear rate, friction coefficient and adhesive force all increase depth below the surface. These variations are attributed to a gradual increasing grain size with depth. The morphologies of the worn track were also studied to understand further the corrosive wear behaviour of gradient surfaces.  相似文献   
195.
In the current literature, empirical and conceptual distinctions have been drawn between a more or less passive short-term memory (STM) system and a more dynamic working memory (WM) system. Distinct tasks have been developed to measure their capacity and research has generally shown that, for adults, WM, and not STM, is a reliable predictor of general cognitive ability. However, the locus of the differences between the tasks has received little attention. We present data from children concerning measures of matrices reasoning ability, reading, and numerical skill along with forward and backward order serial recall of WM, STM, and STM with articulatory suppression tasks. As indices of children's cognitive skills, STM and WM are shown to be rather similar in terms of memory per se. Neither the opportunity for rehearsal nor task complexity provides satisfactory explanations for differences between memory tests.  相似文献   
196.
Functional magnetic resonance imaging (fMRI) was used to compare directly episodic encoding and retrieval. During encoding, subjects studied visually presented words and reported via keypress whether each word represented a pleasant or unpleasant concept (intentional, deep encoding). During the retrieval phase, subjects indicated (via keypress) whether visually presented words had previously been studied. No reliable differences were found during the recognition phase for words that had been previously studied and those that had not been studied. Areas preferentially active during encoding (relative to retrieval) included left superior frontal cortex, medial frontal cortex, left superior temporal cortex, posterior cingulate, left parahippocampal gyrus, and left inferior frontal gyrus. Regions more active in retrieval than encoding included bilateral inferior parietal cortex, bilateral precuneus, right frontal polar cortex, right dorsolateral prefrontal cortex, and right inferior frontal/insular cortex.  相似文献   
197.
The present study focused on the relationship between young children's level of differentiation and creative potential as assessed by the Torrance Tests of Creative Thinking (TTCT). The mothers of high and low creative children were interviewed in order to establish the degree to which they encouraged differentiation in their children. Their level of involvement with their children was also evaluated using the Family Relations Test (FRT). Mothers of high creative children were less emotionally involved with their children than other mothers, less likely to be perceived as overprotective, and less likely to deny their feelings of hostility towards them. They were more self‐confident and self‐realized in their homes and had higher occupational levels than other mothers. The present study also assessed the level of differentiation in both creative and uncreative children with the Draw‐a‐Person and Kinetic Family Drawing Tests. Results indicated that highly creative children were more differentiated than uncreative children.  相似文献   
198.
The model of commitment presented in the present report postulates personality to be the crucial element in the development and maintenance of commitment to the profession of art. The objectives of the research reported here were to (a) demonstrate the typicality of the artist personality and (b) identify the traits which characterize committed and uncommitted artists. Three groups of artists were compared: mature established artists described as committed over a lifetime, committed art students, and uncommitted art students. The instrument used to evaluate personality was the Adjective Check List (ACL; Gough 8c Heilbrun, 1983). Both committed and uncommitted artists presented a typical personality structure; but in contrast to the committed, the uncommitted were characterized by low self‐esteem, a negative self‐image, impaired motivation, low staying power, and an inability to find a clear direction. Both art students and mature artists agreed about the order of importance of 11 factors considered to be determinants of committment. They both placed particular emphasis on autonomy, possibility to experiment, ease of inspiration, and early identification with the profession.  相似文献   
199.
ABSTRACT

Perceived heaviness is a function of both the muscle activity used to wield an object and the resulting movement. Wielding reveals invariant properties of the effector-object system, such as rotational inertia. Recent research has proposed a psychophysiological mechanism for perceiving the heaviness of a handheld object through dynamic touch that captures how arm muscle activity and angular movement combined reveal this invariance (Waddell, Fine, Likens, Amazeen & Amazeen, 2016 Waddell, M. L., Fine, J. M., Likens, A. D., Amazeen, E. L., & Amazeen, P. G. (2016). Perceived heaviness in the context of Newton's Second Law: Combined effects of muscle activity and lifting kinematics. Journal of Experimental Psychology: Human Perception and Performance, 42, 363374.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]). The current study extends this hypothesis by investigating the dynamics of heaviness perception with the leg. Participants lifted objects of varying mass with knee extension lifts while reporting perceived heaviness. During each lift, the electromyogram (EMG) was recorded from the quadriceps, and peak angular acceleration was recorded about the knee. The resulting psychophysiological function revealed the hypothesized ratio of muscle activity to movement, similar to that found in Waddell et al. (2016) Waddell, M. L., Fine, J. M., Likens, A. D., Amazeen, E. L., & Amazeen, P. G. (2016). Perceived heaviness in the context of Newton's Second Law: Combined effects of muscle activity and lifting kinematics. Journal of Experimental Psychology: Human Perception and Performance, 42, 363374.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]. This suggests that the dynamics for heaviness perception in the leg is similar to that shown in the arm in previous work.  相似文献   
200.
The three papers by Modell, Aron, and Greenberg are discussed in terms of their relationship to a new paradigm for understanding the psychoanalytic situation. The paradigm is called social‐construct‐ivist to capture both the idea of the analyst's participation and the idea of construction of meaning. It is argued that these theorists, as well as many of the authors they cite as part of a broad movement in the field, do not consistently meet the criteria for this paradigm, although they seem to be aiming for it. An important source of inconsistency and confusion derives from the confounding of the two axes: drive‐relational and positivist‐constructivist. Many relational theorists who hold fast to the idea that analysts can grasp the truth of both their own experience and that of the patient are no closer to the constructivist point of view than was Freud. The call by Aron and Greenberg for greater attention to the patient's resisted experience of the analyst's subjectivity is discussed in terms of its potential benefits and problems. The ritualized asymmetry of the psychoanalytic situation is said to have important functions, including prevention of excessive involvement and protection of the unobjectionable positive transference and of a degree of idealization. Modell's notion of paradox, which makes the therapeutic relationship seem “real”; and “unreal”; at the same time, is seen as a special instance of the always precarious social construction of reality. It is argued, moreover, that the social and individual aspects of experience are interdependent. Neither is reducible to the other, and both should be understood, like many other issues in the new paradigm, in terms of a dialectical interplay of figure and ground in experience.  相似文献   
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