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   4041篇
  免费   88篇
  国内免费   1篇
教育   3125篇
科学研究   208篇
各国文化   73篇
体育   158篇
综合类   5篇
文化理论   23篇
信息传播   538篇
  2023年   29篇
  2022年   37篇
  2021年   81篇
  2020年   126篇
  2019年   173篇
  2018年   234篇
  2017年   246篇
  2016年   219篇
  2015年   149篇
  2014年   199篇
  2013年   901篇
  2012年   145篇
  2011年   152篇
  2010年   119篇
  2009年   130篇
  2008年   111篇
  2007年   106篇
  2006年   122篇
  2005年   75篇
  2004年   93篇
  2003年   57篇
  2002年   62篇
  2001年   40篇
  2000年   32篇
  1999年   46篇
  1998年   34篇
  1997年   31篇
  1996年   43篇
  1995年   27篇
  1994年   31篇
  1993年   19篇
  1992年   20篇
  1991年   18篇
  1990年   19篇
  1989年   10篇
  1988年   9篇
  1987年   16篇
  1986年   11篇
  1985年   20篇
  1984年   15篇
  1983年   9篇
  1982年   13篇
  1981年   7篇
  1980年   7篇
  1979年   15篇
  1978年   6篇
  1977年   15篇
  1976年   6篇
  1975年   8篇
  1974年   7篇
排序方式: 共有4130条查询结果,搜索用时 31 毫秒
141.
Abstract

Attitude models have been widely applied to natural resource management to ensure responsible environmental behavior. For a variety of applications, the causality among selected antecedents, such as knowledge of environmental issues, locus of control, attitude, personal responsibility, and intention to act on responsible environmental behavior has not yet been tested empirically. A hypothesized causal model based on Hine's (1986) model on responsible environmental behavior was developed. The data from 523 visitors to the urban forest trail in the Kwang-Reung Arboretum, Korea, during September 1995 were used for testing the suggested causal model. Path analysis using the LISREL program tested the model fit and statistical effects of variables. In terms of the effects on intention to act, locus of control and attitude are more important than knowledge and personal responsibility. Our findings suggest that in order to enhance responsible environmental behavior, environmental education and interpretation systems need to focus on changing the internal locus of control. Several recommendations, limitations, and directions for future research are discussed.  相似文献   
142.
143.
The referential, sequential, and inferential dimensions of discourse are explicated and discussed in order to obtain a vantage point from which to view the contributions of speech‐act theory to our understanding of human communication processes. A preview is then provided of four papers, each of which explores the intersection of two or more of these dimensions in order to enrich our understanding of speech‐act theory.  相似文献   
144.
145.
Self-rating bias is particularly likely in organizational behavior research as individuals tend to inflate their expertise, skills and character. This study aims to examine how two culturally diverse groups of teachers and their reporting officers respond to self-ratings of their own teaching skills and leadership skills respectively. It is posited that such response may be culturally based. To ensure validity of comparisons, analyses were done using linear Rasch measures in logits rather than the non-linear raw scores. No significant differences were found between the perceptions of Singaporean teachers and their reporting officers on teaching and leadership skills. The Bahraini data however revealed teachers’ perceptions of own teaching skills were significantly higher than that of their reporting officers. The opposite is true for the Reporting officers’ perceptions of our leadership skills. Bahraini teachers’ perceptions of their own teaching skills were also found to be significantly higher than that of their Singaporean counterparts. The findings support the notion that individuals’ thinking and behavior is influenced by how they process social and cultural information.  相似文献   
146.
147.
Texts in Context     
Elizabeth Yale 《Metascience》2008,17(1):105-109
  相似文献   
148.
149.
In this study, a multiple sample dispenser for precisely metered fixed volumes was successfully designed, fabricated, and fully characterized on a plastic centrifugal lab-on-a-disk (LOD) for parallel biochemical single-end-point assays. The dispenser, namely, a centrifugal multiplexing fixed-volume dispenser (C-MUFID) was designed with microfluidic structures based on the theoretical modeling about a centrifugal circumferential filling flow. The designed LODs were fabricated with a polystyrene substrate through micromachining and they were thermally bonded with a flat substrate. Furthermore, six parallel metering and dispensing assays were conducted at the same fixed-volume (1.27 μl) with a relative variation of ±0.02 μl. Moreover, the samples were metered and dispensed at different sub-volumes. To visualize the metering and dispensing performances, the C-MUFID was integrated with a serpentine micromixer during parallel centrifugal mixing tests. Parallel biochemical single-end-point assays were successfully conducted on the developed LOD using a standard serum with albumin, glucose, and total protein reagents. The developed LOD could be widely applied to various biochemical single-end-point assays which require different volume ratios of the sample and reagent by controlling the design of the C-MUFID. The proposed LOD is feasible for point-of-care diagnostics because of its mass-producible structures, reliable metering/dispensing performance, and parallel biochemical single-end-point assays, which can identify numerous biochemical.  相似文献   
150.
Mass transport in porous materials is universal in nature, and its worth attracts great attention in many engineering applications. Plant leaves, which work as natural hydraulic pumps for water uptake, have evolved to have the morphological structure for fast water transport to compensate large water loss by leaf transpiration. In this study, we tried to deduce the advantageous structural features of plant leaves for practical applications. Inspired by the tissue organization of the hydraulic pathways in plant leaves, analogous double-layered porous models were fabricated using agarose hydrogel. Solute transport through the hydrogel models with different thickness ratios of the two layers was experimentally observed. In addition, numerical simulation and theoretical analysis were carried out with varying porosity and thickness ratio to investigate the effect of structural factors on mass transport ability. A simple parametric study was also conducted to examine unveiled relations between structural factors. As a result, the porosity and thickness ratio of the two layers are found to govern the mass transport ability in double-layered porous materials. The hydrogel models with widely dispersed pores at a fixed porosity, i.e., close to a homogeneously porous structure, are mostly turned out to exhibit fast mass transport. The present results would provide a new framework for fundamental design of various porous structures for effective mass transport.  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