全文获取类型
收费全文 | 12613篇 |
免费 | 135篇 |
国内免费 | 10篇 |
专业分类
教育 | 8657篇 |
科学研究 | 1477篇 |
各国文化 | 152篇 |
体育 | 898篇 |
综合类 | 5篇 |
文化理论 | 125篇 |
信息传播 | 1444篇 |
出版年
2020年 | 139篇 |
2019年 | 229篇 |
2018年 | 242篇 |
2017年 | 301篇 |
2016年 | 258篇 |
2015年 | 171篇 |
2014年 | 266篇 |
2013年 | 2593篇 |
2012年 | 226篇 |
2011年 | 218篇 |
2010年 | 185篇 |
2009年 | 206篇 |
2008年 | 249篇 |
2007年 | 232篇 |
2006年 | 215篇 |
2005年 | 189篇 |
2004年 | 165篇 |
2003年 | 168篇 |
2002年 | 158篇 |
2001年 | 166篇 |
2000年 | 203篇 |
1999年 | 166篇 |
1998年 | 113篇 |
1997年 | 100篇 |
1996年 | 115篇 |
1995年 | 103篇 |
1994年 | 119篇 |
1993年 | 141篇 |
1992年 | 179篇 |
1991年 | 182篇 |
1990年 | 173篇 |
1989年 | 176篇 |
1988年 | 147篇 |
1987年 | 163篇 |
1986年 | 164篇 |
1985年 | 186篇 |
1984年 | 170篇 |
1983年 | 165篇 |
1982年 | 137篇 |
1981年 | 155篇 |
1980年 | 121篇 |
1979年 | 171篇 |
1978年 | 175篇 |
1977年 | 120篇 |
1976年 | 123篇 |
1975年 | 111篇 |
1974年 | 92篇 |
1973年 | 105篇 |
1972年 | 93篇 |
1970年 | 87篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Until comparatively recently the purification of sea or brackish water depended largely on some form of distillation. In recent years, however, a number of industrial concerns have directed increasing attention to processes depending on reverse osmosis. A number of large plants have been installed and this article reviews the present state of reverse osmosis technology and the factors determining its efficiency. Its advantages include its relatively low fuel consumption, and in this respect further substantial savings are in prospect. 相似文献
992.
Dara J. Glasser Kenneth W. Goodman Norman G. Einspruch 《Ethics and Information Technology》2007,9(2):101-109
Radio Frequency Identification (RFID) systems identify and track objects, animals and, in principle, people. The ability to
gather information obtained by tracking consumer goods, government documents, monetary transactions and human beings raises
a number of interesting and important privacy issues. Moreover, RFID systems pose an ensemble of other ethical challenges
related to appropriate uses and users of such systems. This paper reviews a number of RFID applications with the intention
of identifying the technology’s benefits and possible misuses. We offer an overview and discussion of the most important ethical
issues concerning RFID, and describes and examine some methods of protecting privacy.
Norman G. Einspruch serves as a consultant to several high-technology companies, one of which is in the RFID components and
systems business. 相似文献
993.
This article reports original research examining characteristics of the active followers of the American animal rights movement. Typical respondents were Caucasian, highly educated urban professional women approximately thirty years old with a median income of $33,000 (1989). Most activists think of themselves as Democrats or as Independents, and have moderate to liberal political views. They were often suspicious of science and made no distinction between basic and applied science, or public versus private animal-based research. The research suggests that animal rights activism is part of a symbolic manifestation of egalitarian social and political views concerning scientific and technological change. 相似文献
994.
995.
Anita K.W. Chan 《Gender and education》2011,23(6):745-759
Over the past two decades, the feminisation of primary school teaching has been identified by the media and government officials in Western countries as an important contributing factor to boys' academic problems. This panic, which has been criticised by feminists as a backlash and a form of recuperative politics, has promoted the development of research into gender and education, particularly studies related to the gendered culture of primary schools and on the masculinities of male teachers. However, male primary principals remain relatively under-researched in the literature, despite the importance of their structural position and increasing concern over the masculinisation of school leadership. This paper aims to contribute to the discussion by critically analysing the interpretive frameworks of 12 male primary school principals. The findings reveal not only the complex, contradictory and at times culturally specific gendered discourses that some male principals employ, but also their feminising and masculinising effects on the school workplace and leadership. 相似文献
996.
The hypothesis that children develop an understanding of causal mechanisms was tested across 3 experiments. In Experiment 1 (N = 48), preschoolers had to choose as efficacious either a cause that had worked in the past, but was now disconnected from its effect, or a cause that had failed to work previously, but was now connected. Four-year-olds chose the now-connected cause more often than 3-year-olds. Experiment 2 (N = 16) showed 4-year-olds responded appropriately to an irrelevant modification in the same causal system. Experiment 3 (N = 24) demonstrated when the mechanism was batteries rather than connection, 3-year-olds could properly distinguish between relevant and irrelevant modifications. Together, these data suggest that understanding of specific causal mechanisms develops at different ages. 相似文献
997.
Using data from the National Institute of Child Health and Human Development Early Child Care Research Network (NICHD SECCYD), the authors examined whether interactions between home and child-care quality affect children's social-emotional adjustment at 24, 36, and 54 months (N = 771). Triadic splits on quality of home and child care were used to examine children in specific ecological niches, with a focus on those who experience the double jeopardy of poor quality home and child-care environments. Children in this niche exhibited the highest levels of mother-reported problem behavior and the lowest levels of prosocial behavior. However, there was evidence that children from lower quality home environments were able to benefit from the compensatory influence of high-quality child care. These results suggest policies aimed at the cross-context influences of protective and risky settings. 相似文献
998.
Previous work has shown that mothers' employment is associated with increases in children's body mass index (BMI), a measure of weight for height. Nonstandard work (working evenings or nights, weekends, or an irregular shift) may also be associated with children's BMI. This article examines the association between maternal work and children's BMI and considers the influence of mothers' nonstandard work schedules. Using data from school-age children (approximately 8 to 12 years) in the NICHD's Study of Early Child Care and Youth Development (N = 990), this study found that an increase in the total time a mother is employed is associated with an increase in her child's BMI; additionally, the association between maternal employment and children's weight is much stronger at 6th grade relative to younger ages. There was no evidence that maternal or home characteristics or children's time use mediated these associations, nor was there any evidence that nonstandard work was associated with children's BMI. Implications for policy and future research are discussed. 相似文献
999.
Derrick A. Paladino Casey A. Barrio Minton Carolyn W. Kern 《Counselor Education & Supervision》2011,50(3):189-206
The authors propose the Interactive Training Model (ITM), a full classroom role play experience, as a method for helping student counselors develop essential interviewing and counseling skills and self‐awareness as required by the 2009 Council for Accreditation of Counseling and Related Educational Programs Standards. This pre‐post, quasiexperimental study involving 45 master's‐level students indicated that those who participated in the ITM made greater gains in supervisee development compared with those who participated in a traditional peer feedback model. Narrative student feedback regarding the use of ITM in an essential skills course is presented, and implications for counselor education are discussed. 相似文献
1000.
This research examines how youth in arts and leadership programs develop skills for organizing actions over time to achieve goals. Ethnically diverse youth (ages 13-21) in 11 high-quality urban and rural programs were interviewed as they carried out projects. Qualitative analyses of 712 interviews with 108 youth yielded preliminary grounded theory about youth's development of strategic thinking, defined as use of dynamic systems reasoning to anticipate real-word scenarios and plan work. Strategic thinking appeared to develop through youth's creative engagement with tactical challenges in the work and feedback from the work's outcomes. Program advisors supported this development by giving youth control and by providing nondirective assistance when needed. 相似文献