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排序方式: 共有139条查询结果,搜索用时 15 毫秒
81.
82.
ABSTRACT

The aim of this paper is to probe into the social media use by Chinese climate journalists through the examination of their professional practices on social media. Taking COP21 as a case, the study conducted a survey from Chinese COP21 journalists and analyzed WeChat and Weibo posts from Chinese journalists and tweets from their UK and US colleagues. The results show the prevalent use of WeChat among Chinese journalists and the personalization of the social media content accordingly. Compared to their Western counterparts, the use of social media for professional purposes by Chinese COP21 journalists was relatively limited. Nevertheless, several patterns of using social media were identified. Specifically, Chinese journalists tended to more frequently express personal opinions, discuss work experience and favor conventional news sources of authority than UK and US journalists. The results also suggest that climate change in Chinese media discourse will remain more a policy-related issue instead of an environmental or scientific issue, with Chinese government playing a central role.  相似文献   
83.
The ability to quickly locate objects within the visual field has a significant influence on athletic performance. Saccades are conjugate eye movements responsible for the rapid shift that brings a new part of the visual field into foveal vision. The aim of this study was to investigate the effects of sport expertise and intense physical effort on saccade dynamics during a free-viewing visual search task in skilled soccer players. Two groups of male subjects participated in this study: 18 soccer players and 18 non-athletes as the control group. Two sessions of visual search tasks without a sport-specific design were employed. Eye movements during the visual search tasks were recorded binocularly. Between pre- and post-test sessions, athletes performed a maximal incremental treadmill test. Cardiorespiratory parameters were measured continuously. Capillary lactate samples were collected. Pre-test findings indicated that athletes, in comparison to non-athletes, achieve higher values of the following characteristics of saccades (1) average acceleration, (2) acceleration peak, (3) deceleration peak, and (4) average velocity. An increase in post-test saccade duration and a decrease in post-test saccade velocity was observed in athletes due to the strenuous physical effort in relation to the pre-test state. Athletes may transfer high saccadic function efficiency to non-specific visual stimuli. The findings partially confirm that physical exertion can reduce oculomotor efficiency in athletes.  相似文献   
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85.
Adler M  Groisman A 《Biomicrofluidics》2012,6(2):24109-2410916
Mixing of liquids to produce solutions with different concentrations is one of the basic functionalities of microfluidic devices. Generation of specific temporal patterns of concentration in microfluidic devices is an important technique to study responses of cells and model organisms to variations in the chemical composition of their environment. Here, we present a simple microfluidic network that linearly converts pressure at an inlet into concentration of a soluble reagent in an observation region and also enables independent concurrent linear control of concentrations of two reagents. The microfluidic device has an integrated mixer channel with chaotic three-dimensional flow that facilitates rapid switching of concentrations in a continuous range. A simple pneumatic setup generating linear ramps of pressure is used to produce smooth linear ramps and triangular waves of concentration with different slopes. The use of chaotic vs. laminar mixers is discussed in the context of microfluidic devices providing rapid switching and generating temporal waves of concentration.  相似文献   
86.
A broad category of cultural heritage objects are multilayer structures composed of organic, humidity-sensitive materials – wood, animal glue, paper, leather, bone or paints. They respond to variations in relative humidity (RH) in their environment by cyclically gaining and losing moisture, and consequently swelling and shrinking. Differences in the moisture response of the materials induce internal stresses in the individual layers of the structures, which cause objects to deform and crack. Polychrome wood is examined in detail. The cumulative physical damage of the design layer on wood due to repeated RH variations is quantified in terms of their magnitude and number of times they occur. The climatological risk index for accumulated, ‘fatigue’ damage is established, using a procedure to reduce irregular real-world climate histories into simple RH cycles of known damage impact. Using output from the Hadley Model (HadCM3) and simple transfer functions predicting indoor temperature and RH from outdoor climate, changes in the indoor climate through to 2100 were forecast for unheated buildings. European maps highlighting the areas in which painted wood may be significantly affected by climate change are presented.  相似文献   
87.
An increasing number of students with dyslexia register in higher education. As a consequence, information on their pattern of strengths and weaknesses is essential to construct adequate assessment and diagnostic protocols. In a sample of 100 first-year bachelor students with dyslexia and 100 control students, a large pool of cognitive skills were tested using a variety of tests. When we applied an exploratory factor analysis to scores, a model with ten factors fitted the data best. Effect sizes were used to express the processing costs of students with dyslexia. The factors related to reading, spelling, flashed orthography, phonology, naming, math, and reading fluency resulted in large effect sizes. A factor combining all measures for crystallized IQ had a medium effect size. The subtests for fluid intelligence were divided in two separate constructs. Relationships between all subtest scores are visualized and interpreted in a general theoretical and practical framework.  相似文献   
88.
Interchange - The implementation of academic freedom can be difficult both for policymakers and university authorities. A good example of these difficulties is the case of Poland. These...  相似文献   
89.
The success of the Polish private tertiary-level business school, Wy sza Szko ^ a Biznesu-National Louis University (WSB-NLU) in Nowy Sacz, is discussed and analyzed. The reasons for the success of this institution in filling a niche are underlined. While, at the start, the institution was designed as one that would meet local educational needs in a specialized field, it has evolved and has taken on national and even international importance. Most of the institutional success is attributed to the drive and entrepreneurial spirit of the Rector. WSB-NLU is a positive example of education and business enterprise, flexibility, and effectiveness in gaining competitive advantage.  相似文献   
90.
ABSTRACT

Conservation of wooden objects exposed outdoors is extremely difficult and complex due to their constant exposure to fluctuating weather conditions and biological degradation. Filling the gaps in such objects requires the use of specific materials that in particular can adapt to changes in wood dimensions in response to humidity variations. Various materials have been used so far for filling voids in wooden artefacts but none of them was entirely suitable. Therefore, the authors have attempted to provide the basic characteristics of the selected commonly used filling materials based on pine wood powder or glass microballoons as fillers and Paraloid® B-72, Klucel® G, or glutin glue as binders, as the first step in research aiming at developing new and more appropriate gap-fillers. Special attention was paid to the dimensional stability of filling materials upon drying and exposure to water vapour and liquid water. The overall results indicate that among the examined fills those consisting of Paraloid® B-72 and glass microballoons revealed best properties as they were relatively dimensionally stable upon drying and exposure to moisture – despite high absorption of water – and were quite easy to finish. Generally, better properties were observed for filling materials containing higher concentrations of adhesives and these materials will be modified in the next step of the research. Since the main drawbacks of the examined gap-fillers were low water resistance, poor dimensional stability upon drying or exposure to water vapour or liquid water, and fragility or friability, future research into their modification will head towards improvement of the above-mentioned properties.  相似文献   
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