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   1550篇
  免费   10篇
  2024年   1篇
  2023年   3篇
  2022年   1篇
  2020年   6篇
  2019年   7篇
  2018年   281篇
  2017年   204篇
  2016年   258篇
  2015年   13篇
  2014年   7篇
  2013年   17篇
  2012年   50篇
  2011年   176篇
  2010年   179篇
  2009年   42篇
  2008年   74篇
  2007年   77篇
  2006年   1篇
  2005年   95篇
  2004年   36篇
  2003年   13篇
  2002年   7篇
  2001年   1篇
  2000年   2篇
  1999年   2篇
  1997年   1篇
  1992年   1篇
  1991年   1篇
  1989年   1篇
  1973年   2篇
  1971年   1篇
排序方式: 共有1560条查询结果,搜索用时 15 毫秒
111.
A multiproxy approach based on archaeobotanical, organic residue and isotopic analyses was carried out on materials from 12 Medieval archaeological sites in Tuscany (central Italy), in order to provide a diachronic overview of local diet in rural and urban sites from the mid-eighth to the fourteenth centuries AD. Archaeobotanical analyses were applied to 130,578 seeds/fruits, residue analyses involved 87 samples from cooking and storing vessels, whereas analyses of carbon and nitrogen stable isotopes included 63 human bone samples and 26 animal specimens. The results indicate that from the mid-eighth century AD, crop production was of high quality similar, to that of the Roman Age. The main cultivations were naked wheats, barley and horse bean, a diversity that attests the technological skills reached by Tuscan peasants during the whole Middle Ages. Different cereals and pulse abundantly supplemented the diet. This strategy not only ensured peasants’ subsistence in the mid-eighth century AD, minimizing the risks of environmental adversities, but it also increased crop production – from the mid-ninth century AD on, for the revived markets and trade. Between the eleventh and fourteenth centuries AD, C4 plants had a dominant role in the peasants’ diet, when the wheat production was strictly collected first by the landlords and then by the cities for their own needs. Crop production was integrated by swine farming; animal meat consumption is well documented in rural and urban populations from the ninth century AD. Wine and olive oil, considered important elements of diet in Medieval Tuscany, have a very scarce presence, but they are recorded for later periods, mainly in urban areas and in higher social classes, such as the religious and aristocratic ones. In fact, only between the twelfth and thirteenth centuries AD was the great expansion of olive groves and vineyards recorded, when cities and urban populations claim to have access to these luxury foods.  相似文献   
112.
Some of the most notable and largely endangered archaeological remains from the Lake Chad area consist of the ruins of fired-brick elite constructions connected to the Kanem-Borno Empire (ca. eighth–nineteenth century AD). In the course of the last 200 years, several of the elite structures known west of the lake were destroyed as a consequence of war, later having their fired-bricks looted for constructions elsewhere. One of the largest and most thoroughly plundered of those structures once stood within the walled settlement of Garumele, SW Niger Republic. In the scope of an experimental field study at that location and with a view to future work at related sites, we demonstrate that it is still possible to retrace the ground plans of Kanem-Borno fired-brick structures, even if these have been already completely pillaged. In addition, we present new chronological evidence suggesting that Garumele—as a walled urban settlement—was founded sometime between the mid-fifteenth and mid-seventeenth centuries, but most probably between the late sixteenth to mid-seventeenth centuries AD.  相似文献   
113.
The Aterian lithic techno-complex that characterizes the late Middle Stone Age in North Africa is well known especially for its tanged or stemmed points. Recent techno-morphological and use-wear analyses have added new data to support the identification of the tang as the hafted portion of an artifact. They have also highlighted the presence of this attribute on tools other than projectile points, in contrast with the widespread idea that the tanged point is the Aterian fossile directeur. The design of this specific device, the tang, for hafting purposes is regarded as a great technical innovation that underlines a modern behavior. Our work provides new use-wear and experimental data, aiming at discussing the cognitive preconditions of this technical innovation that could have originated from a specific functional unit: the notch. Notches are quite abundant in the Aterian techno-complex. Our systematic study of this tool category from Aterian sites of the Jebel Gharbi allowed defining the notch per se as a techno-morpho-functional unit that was “applied” to different types of blanks, including “reused blanks,” which show a heavy patina on their surface. This functional unit has been used for various types of activities and can be found either alone on a blank or with multiple other units on the same blank, creating different tool morphologies. According to this interpretation, the tang could have been considered by Aterian populations as a new resulting variant of various possible combinations of notches, for defining and/or transforming the shape of a tool.  相似文献   
114.
There is limited available data on the environmental context of the arrival of the first anatomically modern humans (AMH) in North Africa, and subsequent Paleolithic and Neolithic occupations within this region. Microvertebrates such as rodents, shrews, amphibians, and squamates are known to be good indicators of climate and landscape changes. They also represent continental paleoecological records that can be directly related to human occupations. Moreover, faunas and humans have been subjected to several dispersal waves through similar routes, and some rodents may present anthropophilous behavior. Therefore, by understanding the dispersal pattern and pathways of these microvertebrates, it is possible to propose scenarios for human dispersal events. In this study we took the rich microfaunal assemblages from the Témara region, Atlantic Morocco (El Harhoura 2 and El Mnasra Caves), and placed them within a broader synthesis, in order to highlight the role of microvertebrates in providing a better understanding of the human-environment relationship during the Late Quaternary in North Africa.  相似文献   
115.
The Rabat-Témara region of the Moroccan Atlantic coast reveals a succession of Quaternary palaeobeaches. This coastal area is dotted with numerous prehistoric caves. The study of the Upper Pleistocene coastal landscape associated with these caves is of paramount importance in the knowledge of human population subsistence. During the Upper Pleistocene, the ocean level changes drastically influenced the coastal geomorphology as well as the fauna assemblages. The chrono-lithostratographical analysis of the coastal sedimentary formations allows the distinction of three sequences rich in marine fauna. These sequences date from MIS 11 to MIS 5. The identification of malacofauna species from these deposits revealed 39 species, along with Bryozoans, Crustaceans, and Echinoids. These assemblages show a constant fauna cortege highlighted by the dominance of the amphi-Atlantic species Stramonita haemastoma. This species shows an increase in the number of specimens in the uppermost part of marine deposits, probably in relation with a climate warming in the MIS 5. This fauna of both intertidal rocky substrates and sandy substratum indicates environmental conditions close to the present-day Rabat-Témara coastline. As in other coastal locations of Africa from MIS 5, the Middle Stone Age Homo sapiens population benefitted from a littoral environment rich in coastal resources. Comparison between thanatocenoses and archaeological records allows us to identify both species available for Middle Stone Age population and those preferred for human use.  相似文献   
116.
117.
Within the Near Eastern research canon, the transition to more sedentary lifestyles during the Neolithic is often framed as an economic necessity, linked to plant and animal domestication, climatic change and population stress. In such a framework, an increasingly complex social structure, arising in response to the increasingly complex relations of agricultural production, is presumed. For example, some researchers would argue that feasting-based rituals became an arena of social control and an increasingly complex society began to emerge around ritual leadership and monumental ritual architecture. Yet the research projects conducted at many Near Eastern sites indicate neither that sedentism can be directly linked to the requirements of agriculture, nor that the presence of monumental architecture can be successfully associated with social control based on unequal redistribution of agricultural surplus. While ritual activity appears to be central during the Neolithic, two important questions remain to be explored: (1) what exactly did the rituals control, given that the societies under consideration are commonly perceived to have an ‘egalitarian’ ethos?; and (2) what happened to the ritual control in the second half of the PPNB, when ritual architecture completely disappears from the archaeological record at a time of increased reliance on agriculture? Through a critical review of the use of terms like ‘sedentism’, ‘egalitarianism’ and ‘ritual’, I argue that the architecture of the Early Neolithic is related to the management of social relationships through symbolic place-making activities. Based on a comparative review of burial activity, building continuity and the use of symbolic imagery, I examine the symbolic construction of some of the earliest examples of long-term occupational focus in southeast Anatolia, such as Hallan Çemi, Demirköy, Körtik Tepe, Hasankeyf Höyük, Gusir Höyük, Göbekli Tepe, Çayönü and Neval? Çori, in an attempt to understand the social factors behind the emergence and demise of Early Neolithic monumental architecture. The evidence from the above-mentioned sites suggests that Early Neolithic place-making reflects community formation at a variety of scales, at the center of which lay the continuous reinvention of kinship concepts. While some sites, with concentrations of burials, may have become the locus for construction of more intimate local place-based networks, other sites, such as Göbekli Tepe, may have integrated the extended networks. Arguably, the formation of large scale networks during the PPNA posed a threat to local groups. Thus, a focus on local group formation and close control of social exchanges may have begun during the early PPNB, and the places such as Göbekli Tepe may have fallen out of use during this process. In the context of the symbolism and figurine evidence, I further argue that sex and gender may have become important issues, both in the formation of place-communities during the late PPNA—early PPNB, and in the emergence of autonomous households during the later PPNB.  相似文献   
118.
In a talk given at Zurich in the late 1940s, Hermann Weyl discussed Ferdinand Gonseth's dialectical epistemology and considered it as being restricted too strictly to aspects of historical change. His experiences with post-Kantian dialectical philosophy, in particular Johann Gottlieb Fichte's derivation of the concept of space and matter, had been a stronger dialectical background for his own 1918 studies in purely infinitesimal geometry and the early geometrically unified field theory of matter (extending the Mie-Hilbert program). Although now Weyl distantiated himself from the speculative features of his youthful philosophizing and in particular from his earlier enthusiasm for Fichte, he again had deep doubts as to the cultural foundations of modern mathematical sciences and its role in material culture of high modernity. For Weyl, philosophical «reflection» was a cultural necessity he now turned towards Karl Jaspers' and Martin Heidegger's existentialism to find deeper grounds, similar to his turn towards Fichte's philosophy after World War I. The discussion in the late 1940s can be read as a kind of post-World-War-II «Nachtrag» to Weyl's more widely known philosophical comments on mathematics and the natural sciences published in the middle of the 1920s.  相似文献   
119.
We locate Albert Lautman's work as a sort of agent of the break of symmetry in the framework of the traditional opposition of speculative philosophy and the physico-mathematical sciences. The stakes for philosophy are, with very rare exceptions, very poorly perceived. On this level, we return to the question of Lautman's supposed «Platonism» and we confront it with its fundamental reading of Martin Heidegger. The consequences of this insertion in the heideggerian furrow are fundamental for a just restitution of this thought and this philosophy into what they retain in current thought. On the other side, that of Lautmanian entries in the field of mathematical physics, we insist on the extreme prospective alacrity of his gaze, his philosophic power which comes to reinforce this strange sensibility toward what constituted the essential part of theoretical mathematics and physics in his time. In this sense, his position occupies actually one of the nodal points of the «surrationalistic» landscape.  相似文献   
120.
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