全文获取类型
收费全文 | 1742篇 |
免费 | 36篇 |
国内免费 | 1篇 |
专业分类
教育 | 1250篇 |
科学研究 | 162篇 |
各国文化 | 39篇 |
体育 | 87篇 |
综合类 | 4篇 |
文化理论 | 14篇 |
信息传播 | 223篇 |
出版年
2024年 | 5篇 |
2023年 | 16篇 |
2022年 | 16篇 |
2021年 | 43篇 |
2020年 | 57篇 |
2019年 | 88篇 |
2018年 | 114篇 |
2017年 | 122篇 |
2016年 | 107篇 |
2015年 | 81篇 |
2014年 | 103篇 |
2013年 | 356篇 |
2012年 | 78篇 |
2011年 | 91篇 |
2010年 | 63篇 |
2009年 | 68篇 |
2008年 | 47篇 |
2007年 | 48篇 |
2006年 | 54篇 |
2005年 | 18篇 |
2004年 | 31篇 |
2003年 | 31篇 |
2002年 | 25篇 |
2001年 | 14篇 |
2000年 | 14篇 |
1999年 | 14篇 |
1998年 | 9篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 5篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1975年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有1779条查询结果,搜索用时 15 毫秒
111.
In this article, the authors present the fabrication of an enzyme-entrapped alginate hollow fiber using a microfluidic device. Further use of enzyme-entrapped alginate hollow fibers as a biocatalytic microchemical reactor for chemical synthesis is also deliberated in this article. To ensure that there is no enzyme leaching from the fiber, fiber surfaces were coated with chitosan. To confine the mobility of reactants and products within the porous hollow fibers the entire fibers were embedded into a transparent polydimethylsiloxane (PDMS) matrix which also works as a support matrix. A vanadium-containing bromoperoxidase enzyme isolated from Corallina confusa was used as a model enzyme to demonstrate the use of these alginate hollow-fiber reactors in bromo-oxidation of phenol red to bromophenol blue at different dye flow rates. Stability of the entrapped enzyme at different temperatures and the effect of the chitosan coating on the reaction conversion were also studied. It was observed that molecules as big as 27 kDa can be retained in the matrix after coating with chitosan while molecules with molecular-weight of around 378 Da can still diffuse in and out of the matrix. The kinetic conversion rate in this microfluidic bioreactor was more than 41-fold faster when compared with the standard test-tube procedure. 相似文献
112.
Kyung-Sun Kim Sei-Ching Joanna Sin EunYoung Yoo-Lee 《Library & information science research》2021,43(3):101104
This cohort study examined longitudinal changes in undergraduates' use of social media as information sources in academic and everyday-life contexts, covering types of social media used, purposes of use, and evaluation strategies. Web surveys were used, collecting data from 1,355 and 928 undergraduates in 2013 and 2019. The study found that students used most types of social media less in 2019 than 2013 in both contexts. Only media-sharing services bucked this downward pattern. Overall, a majority of social media types underwent changes in the top three purposes of use. The 2019 cohort used most evaluation strategies more frequently in both contexts. However, they favored simplistic strategies relying on superficial physical cues when evaluating information. Based on the findings, this study provided recommendations for information literacy education and interface design, such as covering multimedia information evaluation, leveraging various heuristics to prime careful use of social media and analytical evaluation of information. 相似文献
113.
Alghamdi Amani Khalaf H. Al Ghamdi Kholoud S. Kim Sun Young 《Journal of Science Education and Technology》2022,31(5):583-593
Journal of Science Education and Technology - It is of great importance that science educators teach COVID-19 and related pandemics to boost students’ scientific literacy. A mixed methods... 相似文献
114.
Comprehension Tools for Teachers: Reading for Understanding from Prekindergarten Through Fourth Grade 总被引:1,自引:0,他引:1
115.
The Expression of Depressive Symptomatology in Korean American Undergraduates: Sex and Generational Differences
下载免费PDF全文
![点击此处可从《Journal of College Counseling》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jeanett Castellanos Alberta M. Gloria Sara Cho Kim Yong S. Park 《Journal of College Counseling》2014,17(3):208-221
This study examined the influence of acculturation and perception of the university environment on the depressive symptomatology of 228 Korean American undergraduates, with a focus on sex and generational differences. Perceptions of the university environment and perceived barriers were positive predictors of depressive symptomatology in respective regression equations by sex and generation. Study limitations and counseling practice implications are discussed. 相似文献
116.
This study scrutinizes Asia Pacific Education Review (APER) that has been weathered 13 years of journey from its inception. Numerically, 504 peer-reviewed articles have been published so far, and 0.5 of impact factor has been achieved. This article recollects the history of APER, overhaul the accomplishment and shortcomings of it. Through an overview of the annually submitted and published articles, 14 domains of research area, research methods, and the demographics of contributors were examined; 30 nationalities of authors’ papers were published, and 2/3 of articles used quantitative research method. The most published domains were educational administration and policy, educational psychology and special education, and higher education; however, the most cited articles covered all research area of education impartially. This study also suggested APER’s contribution to the advancement of education research community internationally and interdisciplinarily. 相似文献
117.
Many household consumables contain volatile organic compounds(VOCs)as the active ingredient.Long term exposure to VOCs could cause various health problems,especially to the respiratory system.Graphene has attracted a lot of attention recently for its potential to be used as sensing material for VOCs.In this project we have constructed graphene/PVA composite based gas sensors for VOC detection.It was perceived that the polymer could introduce better selectivity to the sensor.Results suggest that the proposed sensor is highly sensitive to low molecular weight VOCs and that the manner in which the sensor respond to the vapour depends on the polarity or hydrophobicity of the vapour. 相似文献
118.
119.
120.
Young Yun Kim 《Int J Intercult Relat》1978,2(2):197-224
This paper explores a theoretical and methodological basis for studying foreign immigrants' acculturation processes from a communication perspective. Communication patterns of immigrants are conceptualized on three levels — behavioral, attitudinal, and perceptual. The behavioral level of communication includes the immigrant's participation in communication channels of the host society as well as the ethnic community. The perceptual level refers to the immigrant's cognitive structure in perceiving the host society. The attitudinal level is examined by the immigrant's affective-evaluative orientation toward the host society. The three levels of communication patterns were empirically investigated in a survey of 400 randomly selected Koreans in the Chicago area. The communication variables were assessed through composite scores using questionnaire items that were tested for reliability. The results show an overall linear trend in the immigrant's interethnic communication with Americans, positive attitude toward Americans, cognitive complexity in perceiving the American society, and satisfaction level. A simultaneous increase is observed in the immigrant's interpersonal communication with Americans and with other Koreans. The immigrant's use of ethnic media rapidly decreases over the years while that of American media steadily increases. Findings are discussed in comparison to previous studies of foreign immigrants and students and to sociological theories of acculturation of minority groups. 相似文献