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   185篇
  免费   0篇
  国内免费   7篇
教育   140篇
科学研究   22篇
体育   5篇
综合类   9篇
文化理论   8篇
信息传播   8篇
  2022年   1篇
  2021年   2篇
  2020年   9篇
  2019年   8篇
  2017年   2篇
  2016年   3篇
  2015年   4篇
  2014年   20篇
  2013年   8篇
  2012年   8篇
  2011年   13篇
  2010年   6篇
  2009年   7篇
  2008年   9篇
  2007年   14篇
  2006年   15篇
  2005年   11篇
  2004年   10篇
  2003年   7篇
  2002年   4篇
  2001年   13篇
  2000年   5篇
  1999年   3篇
  1998年   2篇
  1997年   3篇
  1996年   2篇
  1995年   2篇
  1994年   1篇
排序方式: 共有192条查询结果,搜索用时 31 毫秒
51.
应用分子力学方法MMP和半经验量子化学AH1法得到了18种有机气体的优势构象,利用量子化学算法和分子图形学技术获得电子结构、几何结构和拓扑结构参数,并将这些参数与有机气体的麻醉活性参数相关联。结果表明:有机气体的麻醉活性与分子的极化率和辛醇/水分配系数的相关性较好,成功地建立了18种有机气体的构效关系武。  相似文献   
52.
The microclimatic analysis of the Petrarca's tomb in Arquà Petrarca, Padua (Italy) was performed to assess the suitability of a closed environment located outdoors respect to the conservation requirements of heritage materials. Results showed that the thermo-hygrometric conditions inside the tomb were not suitable for the conservation of organic materials, like bones and wood. The orientation (north or south) was the main responsible for the different damage features of the two sides of the wooden case housing the human remains inside the tomb. Technical solutions were finally implemented to improve the conservation conditions, thus avoiding further damage.  相似文献   
53.
This paper seeks to investigate the relationship between organizational organic structure and intellectual capital improvement. Researches show that the organic structure and intellectual capital have a strong relationship but this relationship has not been examined systematically. This paper reviews the important theoretical work in both streams of research, highlighting the fundamental similarities and differences. Models of intellectual capital are compared, and the distinction between social, human and organizational capital is examined. The nature of organizational organic structure is presented. We examine the relationship between organic structure and intellectual capital improvement. Then the impact of organic structure on information management and information processing capability is examined.The results support the view that organic structure has a positive impact on intellectual capital. Therefore, the organic structure can improve intellectual capital in the organization.This study helps managers to design flexible and dynamic organizational structures to enhance the intellectual capital in the organization and increase the ability to compete.  相似文献   
54.
论述了在有机合成中选择控制的重要性,结合教学实践归纳总结了各种选择控制的策略和办法。  相似文献   
55.
本文基于对高师院校科技创新及其运行机制的现状分析,通过借鉴国内外成功的科技创新组织形式的经验,提出了高师院校实现科技创新的基本途径。  相似文献   
56.
Purpose: The purpose of this study is to investigate the impact of interpersonal communication on the adoption of agri-environmental measures (AEM) by organic farmers in Germany.

Methodology: The study used the logit model to predict the probability of adoption behaviour, and Social Network Analysis (SNA) was conducted to analyse the question of whether validating information about organic farming provided by interpersonal information sources is associated with communication frequency.

Findings: Our findings demonstrate that being an early adopter of organic farming practices and frequent contact with young and highly educated farmers increases the probability of adoption of other AEM. However, contact frequency in interpersonal networks was found not to be a significant determinant for explaining adoption decisions. Frequently communicating farmers in the network are more likely to attribute higher levels of importance to organic farming information received from formal actors than to information received from informal actors.

Practical Implications: If young and highly educated farmers, who can be considered as informal opinion leaders, are approached by the extension services, then an effective diffusion of information on AEM can be expected. To support the AEM adoption, a platform should be provided by state agencies that would enable organic farmers to understand the environmental benefits achieved over the time.

Originality/value: This study contributes to the scientific discussion on the role of interpersonal communication on AEM adoption. A new aspect is our consideration of organic farmers adopting additional AEM. Moreover, we highlight organic farmers' validation of the importance of formal and informal information sources on organic farming.  相似文献   

57.
研究目的:在"干清粪"系统猪粪堆肥过程中,不同添加剂(玉米秸秆、锯末和蘑菇渣)处理对甲烷、氧化亚氮和氨气排放的影响。创新要点:将不同的添加剂(玉米秸秆、锯末和蘑菇渣)应用到快速堆肥系统中进行堆肥,测定了猪粪堆肥过程中甲烷、氧化亚氮和氨气的排放规律,为国内猪粪堆肥的应用提供理论指导。重要结论:玉米秸秆作为添加剂能增加猪粪堆肥过程中氧化亚氮的排放;蘑菇渣添加剂增加了堆肥过程中甲烷的排放,然而减少了氧化亚氮及氨气的排放;锯末处理能增加堆肥过程中氨气的排放。添加剂能显著影响堆肥过程中氮素的损失。  相似文献   
58.
文章以人本主义教育理论为指导,从以下三个方面对有机化学教学进行探析:如何以人为本激发学生的内在潜力;如何转变教师的角色;如何建立激发学生的兴趣的有效机制.从而培养学生的能力,提高学生的综合素质.  相似文献   
59.
分析了积雪光谱与其中污染物含量的关系.研究发现随污染物含量的增加,350~850nm处积雪的反射率急剧降低.用非线性回归方法,对污染物含量敏感的波长进行分析.结果显示,在384nm处,随污染物含量的增加,反射率以对数的形式变小;而在1495nm处,随污染物含量的增加,反射率以指数的形式增加.同时从所测光谱中,选择TM各个波段的中心波长与污染物进行相关分析,得到和逐波段与污染物进行相关分析一致的趋势,因此可以将该方法结合TM影像来预测积雪中污染物的含量.  相似文献   
60.
无溶剂条件下的有机合成,具有收率高、选择性强、操作简便、成本低及无环境污染等优点,是绿色化学的重要内容.综述了近年来发现的无溶剂有机反应类型.  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