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   317篇
  免费   20篇
  2024年   1篇
  2023年   12篇
  2022年   7篇
  2021年   3篇
  2020年   14篇
  2019年   15篇
  2018年   35篇
  2017年   24篇
  2016年   11篇
  2015年   13篇
  2014年   15篇
  2013年   38篇
  2012年   20篇
  2011年   19篇
  2010年   15篇
  2009年   14篇
  2008年   9篇
  2007年   10篇
  2006年   10篇
  2005年   5篇
  2004年   2篇
  2003年   3篇
  2002年   3篇
  2001年   2篇
  2000年   6篇
  1999年   3篇
  1998年   3篇
  1997年   3篇
  1996年   6篇
  1995年   1篇
  1994年   3篇
  1993年   1篇
  1992年   1篇
  1989年   2篇
  1988年   2篇
  1987年   1篇
  1985年   1篇
  1983年   2篇
  1982年   1篇
  1980年   1篇
排序方式: 共有337条查询结果,搜索用时 15 毫秒
51.
This article aims to dissect Thomas Abbt's (1738–1766) theory of aesthetic patriotism as laid out in his On Dying for the Fatherland (1761) and his prize-essay On Mathematical, Metaphysical and Moral Certainty (1763). Aesthetic idioms, such as the emphasis on the intrinsic pleasure from the order and beauty of virtue, had been invoked throughout the eighteenth century to vindicate the morally optimistic view of humanity against the sceptical vision of an exclusively utility-centred mankind. In the post-Montesquieu debates on the moral foundations of modern politics, German-speaking authors in particular, from both republics (Switzerland) and monarchies (Prussia), appropriated the aesthetic idioms in order to reject those theories which grounded patriotism in some sort of self-interest or proclaimed it redundant in modern society. Thomas Abbt was one of the most prominent representatives of this intellectual position. Combining the general emphasis of Shaftesbury on the role of aesthetic appreciation in moral and political agency with the more specific German Baumgartenian analysis of ‘beauty’ as a central principle in human ‘empirical psychology’, Abbt argued that patriotism in modern monarchies could be grounded in an aesthetic passion of enthusiasm generated through sensuous examples of great virtue. The example of a king fighting for his country on the battlefield could inspire monarchical subjects to follow his example as well as regenerate patriotism among them. Abbt was adamant that patriotism based on aesthetic foundations had to be supported and stabilised by a pervasive patriotic culture of remembrance and emulation of dead heroes through the fine arts, as well as by a system of meritocratic honour in the army.  相似文献   
52.
The analysis of environmental archives from across the world has demonstrated that human perturbation of the geochemical cycles of trace metals and the resultant atmospheric metal contamination date back, at least, several millennia. However, an understanding of the local processes and timing of changes in trace metal deposition is also essential for a proper global interpretation. The Iberian Peninsula was a major mining area since prehistoric times and the analysis of environmental archives provides a good opportunity to improve our understanding of the history of mining and metallurgy in Europe. We present the results from three 14C dated peat cores from the Xistral Mountains (NW Iberia). These records are used to reconstruct past atmospheric deposition of Ni, Zn, As, and Cd. The chronology of the changes in concentrations and metal accumulation rates was found to be concordant in the three bogs, and showed great similarity to total Pb, Hg, and Pb isotope ratios as determined in previous investigations. They present a consistent view of changes in atmospheric pollution and the importance of metals in the development of human societies, especially: i) the first evidence of atmospheric metal pollution 3400 years ago, which is simultaneous with the expansion of the Atlantic Bronze Koine; ii) a pollution event between 2350 and 2150 years ago, associated to the development of so-called Celtic culture (local Late Iron Age); iii) a dramatic increase of metal fluxes in Roman times; iv) a severe and rapid increase in the last 250 years corresponding to the beginning of the industrial revolution in Europe, reflecting the emergence of the new dominant sources of pollution, and v) the increase of long range atmospheric transport of pollutants. Our data suggest that all detected ancient (until ca. 1450 cal BP) periods of enhanced Ni, Zn, As, and Cd accumulation may have had an anthropogenic origin, related to the onset and development of mining and metallurgy.  相似文献   
53.
54.
我国旅游业研发总体水平、区域分布与政策建议   总被引:3,自引:3,他引:0  
本文利用文献法和定量分析等方法,深入分析了我国旅游业技术和研发现状。针对我国旅游业研发总体水平低,研发能力集中于发达地区等问题,从观念、政府、机构、人才等方面提出了具体政策建议。  相似文献   
55.
Alzira is situated in a cut-off meander loop of the Rio Júcar. Geo-archaeological study shows that the Islamic city wall was built during the second quarter of the 11th century AD, at a time when the river had a low-amplitude and low-energy flood regime. After mid-century, overbank silts began to invade the city as peak flood discharge increased, with a spate of destructive floods reflected by high-energy deposits during the late 11th century. Urban expansion within the city wall is dated to the later 11th or early 12th century, interrupted by local abandonment and moderate-energy flood silts. Major construction during the mid-12th century was followed by protracted abandonment (after a siege in AD 1171?) and further, moderate-energy flood silts that redistributed occupation and collapse debris. Reoccupation, during the late 14th century, was terminated by catastrophic floods in 1517 and 1571, after which much of the western end of Alzira was not rebuilt. Following further flood catastrophes during the 17th century, parts of the central walled city remained abandoned until the 19th century. with new occupation atop flood sands of yet another disaster in 1864. The change in flood regime after 1150 was a result of deforestation of the watershed, but progradation of a downstream tributary fan after 1517 created an unstable, aggrading floodplain increasingly prone to severe flooding. Climatic anomalies were responsible for periods of recurrent severe floods, archaeologically verified during the 11th and 12th centuries, and historically documented, beginning in 1318. The geo-archaeological methodology illuminates the constructional and settlement history of Alzira, allows distinction of fluvial and cultural components, and provides the necessary microstratigraphic detail and dating control to document the true complexity of alluvial processes during the last 1000 years.  相似文献   
56.
57.
58.
59.
ABSTRACT

Recent research has focused on the impacts of environmental change to tourism. In particular, the perceived costs of climate change have been increasingly studied. However, the relationship between costs and benefits resulting from the changing environmental conditions for the industry has been less examined. This paper identifies the locally observed changes in the natural and socio-economic environments and aims to analyse the financial costs and benefits to tourism businesses in two tourism-dependent communities in northern Finland. The specific focus is on adaptation and adaptive management in a tourist destination scale. Adaption is understood as an investment creating not only implementation costs, but potentially also benefits for tourism operations. Research materials were collected among tourism and tourism-related businesses through 41 semi-structured thematic interviews. Results indicate that the evaluated benefits of environmental change seem to exceed those of costs. This conforms to the on-going discourse of climate change–tourism relations associated with the Arctic region where both awareness and vulnerability to change are considered relatively high but the level of responses, i.e. adaptation, low. These results can help to further identify the most vulnerable sectors in tourism and assist entrepreneurs preparing for environmental and climate change. However, the paper concludes that while global environmental change, with specific adaptive management strategies, may create local short-term direct benefits for the industry, a long-term sustainability of tourism in the Arctic calls for mitigation responses to climate change.  相似文献   
60.
During the Upper Paleolithic, lithic variability is one of the most important keys to recognize hunter-gatherer behavior, technology, ecology, and social dynamics. The origin and expansion of Gravettian populations in Eurasia has been seen as one of the most critical episodes in human evolution, argued to be the first clear evidence of the so-called polymorphism among modern human populations. In the case of southern Iberian Peninsula, recent data have shown a new regional and diachronic organization for the Gravettian occupation in this region. Therefore, the interpretation of such variability is one of the most important questions, and functional analysis is a fundamental proxy to recognize human technological, settlement and ecological adaptations as major factors for this polymorphism. This study focused on lithic use-wear analysis of the Early Gravettian of Vale Boi (southern Portugal), in order to understand lithic technological organization and variability within and between occupations at the site. Results show similar patterns between assemblages, showing that different materials were worked at the site, although showing reduced time of work, low variability and percentage of pieces used. Unlike other Gravettian contexts in southern Iberia, the Early Gravettian from Vale Boi is characterized by some variability of backed points, marked by the predominance of bipointed double-backed bladelets. Functional analysis of the Early Gravettian lithic industries of Vale Boi provide a new insight to interpret human technology and settlement strategy during the onset of Upper Paleolithic industries in western Eurasia.  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