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   221篇
  免费   8篇
  2024年   1篇
  2023年   3篇
  2022年   2篇
  2021年   2篇
  2020年   9篇
  2019年   6篇
  2018年   10篇
  2017年   6篇
  2016年   12篇
  2015年   9篇
  2014年   9篇
  2013年   33篇
  2012年   11篇
  2011年   12篇
  2010年   21篇
  2009年   18篇
  2008年   11篇
  2007年   4篇
  2006年   2篇
  2005年   9篇
  2004年   3篇
  2003年   5篇
  2002年   1篇
  2001年   2篇
  2000年   4篇
  1999年   3篇
  1998年   1篇
  1997年   2篇
  1996年   1篇
  1994年   1篇
  1993年   1篇
  1991年   1篇
  1987年   2篇
  1985年   1篇
  1984年   2篇
  1983年   1篇
  1982年   2篇
  1977年   2篇
  1976年   1篇
  1975年   2篇
  1970年   1篇
排序方式: 共有229条查询结果,搜索用时 15 毫秒
51.
This paper explores potential barriers to growth in key areas which can become increasingly problematic for some smaller to medium-sized firms (SMEs) as they grow and evolve from their early status as small scale spin-offs. These potential growth barriers can occur in: finance, competition from new firms or products and organizational integration of resources. Firms that fail to properly plan, manage and allocate resources will encounter difficulties in each area. Such firms are said to have poor 'governance systems'. While not proposing a universal theory about small firm behaviour, we argue that firms can encounter the same problems associated with poor communication, bureaucracy and loss of entrepreneurial spirit that plague large firms. We also show that the routines used to promote growth based on collaboration can sometimes create problems for firms as they ignore new challenges. We elaborate various theories on the limits to growth by examining the case of IV, a university spin-off.  相似文献   
52.
传统的冷冻脱水过程通常需要将电阻温度传感器(RTD)插入到物料中以监测温度变化从而确定干燥终点,这种方式对于处理木质文物来说具有一定的破坏性,无法做到无损或微损。本研究尝试采用无损方式对定型加固剂浸渍液即时浓度进行分析,并对冷冻干燥终点进行预测。采用这种无损技术成功地对志丹苑元代水闸遗址出土的30件木构件进行真空冷冻脱水定型处理,既达到了预期的定型保护效果,又确保了木构件的安全。  相似文献   
53.
54.
This guest editorial reflects on the problem of ‘information overload’ in social anthropology, suggesting that technological advancements such as automated indexing provide an opportunity to question certain assumptions and ingrained practices in the field.  相似文献   
55.
ABSTRACT This paper examines the continued strong population growth in U.S. nonmetropolitan areas possessing high levels of natural amenities during the 1990s and the reasons for near convergence of growth across the top tiers of the amenity hierarchy. Based on estimated parsimonious spatial hedonic growth regressions, strong demand for high‐amenity areas continued in the 1990s, but the converging of population growth across the top tiers appeared related to capitalization of amenity differences among the tiers into factor prices. Yet, evidence obtained from controlling for spatial effects suggests that the relative quality of life in the top two tiers had deteriorated.  相似文献   
56.
We drove from Beijing to Tianjin,guided by GPS.We got lost several times in the crowded city and had to continually send messages to Mr.Liu Dong to get directions by mobile phone.Finally in the thick of the city buildings,we found a Tibetan-style flat-roofed building that was colored red and white  相似文献   
57.
<正>Even in my very early days in Tibetan Buddhist art circles,art auctions and even academic circles, I had not only heard the name Yesi but I also read his ill...  相似文献   
58.
选择华商与韩商大会作为个案,运用比较研究的方法,对华商网络与韩商网络的运营机制及其特征进行了阐述和分析。韩商大会与华商大会是两个最具规模的离线网络协力系统,在强化网络成员之间的联系与沟通乃至在构筑民族共同体方面具有十分重要的意义。两个大会在会议周期、运营体系和世界性影响力方面又具有很大差异。  相似文献   
59.
Dan Cohen  Emily Rosenman 《对极》2020,52(5):1259-1285
In the face of planetary crises, from inequality to biodiversity loss, “impact investing” has emerged as a vision for a new, “moral” financial system where investor dollars fund socio-environmental repair while simultaneously generating financial returns. In support of this system elite actors have formed a consensus that financial investments can have beneficial, more-than-financial outcomes aimed at solving social and environmental crises. Yet critical geographers have largely studied “green” and “social” finance separately. We propose, instead, a holistic geography of impact investing that highlights the common methods used in attempts to offset destructive investments with purportedly reparative ones. This involves interrogating how elite-led ideas of social and environmental progress are reflected in investments, as well as deconstructing the “objects” of impact investments. As examples, we use insights from both “green” and “social” literatures to analyse the social values embedded in projects of financialisation in schooling and affordable housing in the US.  相似文献   
60.
出土、出水饱水木质文物冷冻干燥研究进展   总被引:1,自引:0,他引:1  
冷冻干燥是稳定出土、出水饱水木质文物的主要方法之一。该方法基于水由固态直接成为气态的升华过程不产生表面张力的原理,可避免饱水木材脱水时受到干燥应力的破坏。数十年来,经过实验实践和不断完善,冷冻干燥在出土、出水降解木材的稳定中取得了很好的效果,在大型、厚重木质文物的保护方面得到成功应用。本研究基于在出土、出水含盐饱水木质文物保护方面的多年实践,对国内外在脱盐、抗菌、热浸、预冻和升华干燥工艺等方面的进展进行了回顾,并提出了解决一些现有问题的技术设想。  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