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101.
The paper deals with dendrochronological and radiocarbon dating of subfossil trunks found in the basin of the Morava River.
The research into subfossil trunks had been conducted in the Czech Republic in the past but the research stopped in 2001.
160 records of measurements of subfossil, predominantly oak trunk samples, are preserved from that time. Three years ago the
research was reopened and again the most trunks were found in the basin of the Morava River. 92 samples of oak trunks and
7 samples of other tree species (poplar, elm, maple, beech) were taken from selected sites. The samples were processed in
compliance with the standard dendrochronological methodology. To date the samples, Czech, Austrian, Polish and German standard
chronologies were used. In cases when the dendrochronological dating was unsuccessful, the samples were sent for radiocarbon
dating. In total, 35 samples were dated, mainly by the radiocarbon method. Subfossil trunks from gravel pit Tovačov were dated
and classified into 4 different periods, the oldest being from 2780–2190 BC. In Osek nad Bečvou, the samples were taken from
two sites. Whereas from the 4 trunks taken in the river channel each was from a different period, the trunks from the gravel
pit come from 981–1015 AD. The trunks found in the Morava River basin near Strážnice were dated to the 10th–15th century. In the future, we expect to extend the amount of the acquired samples with the aim to create a link to the existing
standard chronology or to create a long floating average treering curve. 相似文献
102.
Bernadett Bajnóczi Gabriella Schöll-Barna Nándor Kalicz Zsuzsanna Siklósi George H. Hourmouziadis Fotis Ifantidis Aikaterini Kyparissi-Apostolika Maria Pappa Rena Veropoulidou Christina Ziota 《Journal of archaeological science》2013,40(2):874-882
Determination of the source of Spondylus objects is essential for the interpretation of Late Neolithic exchange systems and the social role of shell ornaments. We performed stable isotope analysis combined with cathodoluminescence microscopy study on ornaments (beads, bracelets) made of Spondylus shells excavated at the Aszód-Papi földek archaeological site in Hungary, to define their origin. For comparison Spondylus finds from Neolithic sites of Greece, modern Spondylus shells from the Aegean and the Adriatic, as well as fossil Spondylus and Ostrea shells from the Carpathian Basin were also examined. Oxygen isotope composition of Spondylus finds from Aszód ranges between ?1.9 and 2.1‰ and overlaps with the oxygen isotope range of shell objects from other Neolithic sites. Modern Spondylus shells from the Aegean and the Adriatic show overlapping δ18O values with one another and with the Neolithic objects; while recent shells of the Black Sea clearly are separate isotopically from the Mediterranean ones and most of archaeological artefacts. Spondylus shells from the Aszód site have Mediterranean origin; their source can be the Aegean or the Adriatic. Based on a former strontium isotope study the use of fossil Spondylus shells is excluded as raw material used for ornaments, however, in recent years the use of fossil shells was reintroduced. The shell ornaments from Aszód-Papi földek and the fossil oyster shells collected from the Carpathian Basin exhibit some overlapping oxygen isotope values; however, cathodoluminescence microscopy indicates that the Spondylus objects retained their original aragonite material. Diagenetic calcite, which occurs typically in the fossil shells, was not detected in the ornaments suggesting that the studied objects were made of recent shells. Calcitic parts observed in some Spondylus objects are not related to fossilisation. 相似文献
103.
María Gabriela Musaubach Anabela Plos María Del Pilar Babot 《Journal of archaeological science》2013,40(2):1186-1193
This paper presents, for the first time, a detailed study, from an archaeological perspective, of the morphological characteristics of the starch grains within the kernels of selected native wild grasses found in the Central Pampas of Argentina. We compared native wild grasses to maize starch grains, which can be distinguished from each other based on their size, shape and other attributes. The majority of the studied grains did not share morphological characteristics with maize starch grains. Considering this, it can be said that, if irregular and polyhedral grains with transverse or radial fissures dominate the starch assemblage, maize identification may be done on the basis of both morphology and size. Additionally, this research contributes to the characterization of the starch grains of the Panicoideae subfamily, which includes maize. Several classes of simple and compound starch grains are described and defined for native species of Pooideae, Chloridoideae, Arundinoideae, and Panicoideae subfamilies. The results obtained may constitute a baseline for the future determination of maize and wild grass use in archaeological contexts belonging to Middle/Late Holocene hunter–gatherers in the Pampas of Argentina and neighboring areas. 相似文献
104.
G. Huelga‐Suarez M. Moldovan M. Suárez Fernández M. Ángel de Blas Cortina J. I. García Alonso 《Archaeometry》2014,56(4):651-664
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing. 相似文献
105.
Alexandr Chvátal 《Journal of the history of the neurosciences》2014,23(4):367-376
Ji?í (George) Procháska (1749–1820), a Czech anatomist, physiologist, and neuroscientist of the eighteenth century, ranks among the major figures of Czech and European cultural history. The works of Ji?í Procháska, due to historical circumstances, were published mostly in Latin and only some in German. However, given that only one treatise was partially translated into English, the results of his extensive research activities are currently unavailable to the international scientific community. The achievements of Ji?í Procháska undoubtedly belong to the major intellectual heritage of European science and certainly deserve attention as such, although his research reflected the time in which he lived and therefore has been reevaluated by later researchers. Undoubtedly, it is our duty not only to remember the work and legacy of Ji?í Procháska, which significantly influenced the development of our knowledge, but also to try to critically assess his contribution in terms of today. This article surveys the important biographical events of Ji?í Procháska’s life, taking into account the significance of his research. 相似文献
106.
Relying on stochastic frontier analysis we propose a methodology to study the technological characteristics and cost efficiency levels related to the provision of public infrastructure for basic utilities. The methodology assumes a cost minimizing behaviour on the part of public officials when planning the construction of local infrastructure, which is represented by way of a flexible translog cost function. Introducing relevant definitions of scale economies, associated with larger numbers of inhabitants and dwellings, as well as economies of density, brought about by reductions in urban dispersion, we analytically determine the optimal population densities for which average cost is minimized. We illustrate our model with the water cycle sector, including water distribution, sewage collection and cleansing of wastewater, and considering data at the municipality level for the Spanish region of Castilla y León. The obtained results indicate potential cost savings in the form of decreasing average costs, as relevant scale and density economies are present, along with large inefficiency levels. Relevant policy guidelines favouring larger and denser urban sizes are drawn, as the observed cost excess is the result of a general suboptimal urban size in terms of population density, and the negative effects of dispersed settlement patterns. 相似文献
107.
108.
City districts are often classified as ‘rich’ or ‘poor,’ a phenomenon that occurs within cities all over the world. While income inequality, wealth inequality, and other kinds of social inequality are frequently tracked, there is a surprising lack of research concentrating on how social inequality manifests as differences between parts of cities, especially outside of the U.S. That is mostly due to insufficient available data. In this paper, we propose a methodology for measuring the relative inequality between city districts by using the average prices of residential properties in various parts of the city, and assessing their relative difference. This approach has several advantages, as property listings are often readily available even in cities where income data is not. This methodology has potential for measuring developments in inequality in a much wider range of cities. As a proof of concept, we apply this methodology to property prices in Prague during the period 2003–2012 to identify a trend of either growing or decreasing inequality among individual parts of the city. We have found that during this period the disparity has grown only 5.97%, which means the overall growth of disparity between the city districts was negligible. 相似文献
109.
Olga Löblová 《政策研究杂志》2018,46(1):160-189
Epistemic communities are an established concept in the study of international relations but can also explain policy change at the domestic level. This article asks why some epistemic communities manage to convince decision makers of their preferred policies while others do not. It suggests that the reason lies in the causal mechanism of epistemic communities' influence on decision makers, mediated by decision makers' demand for expert input. Most epistemic communities scholarship focuses on single case studies where the communities' influence on policy was strong and clear, leading to an overestimation of the groups' influence. To help correct this probable bias, this article compares a successful case of epistemic community influence (health technology assessment in Poland) with an unsuccessful example of the same policy (in the Czech Republic). The juxtaposition allows for unpacking of the necessary parts of the causal mechanism (emergence of an epistemic community, its activity, access to decision makers, and successful suasion) and separating them from the crucial scope condition. Decision makers' uncertainty about the policy issue at hand has traditionally been the key scope condition for epistemic communities but the successful Polish case demonstrates that epistemic communities can be influential even in highly certain areas of routine policymaking, leading to a reconceptualization of uncertainty as policymakers' demand for expert input. Demand can originate from various sources, but any change of it affects individual parts of the causal mechanism, leading to a success or failure of epistemic communities' policy enterprise. 相似文献
110.
J. Petřík D. Sosna L. Prokeš D. Štefanisko P. Galeta 《Archaeological and Anthropological Sciences》2018,10(4):893-904
Despite the large-scale expansion of Bell Beaker phenomenon, there is a tension between the normative Bell Beaker material culture categories and their local objectification in the form of real artefacts. Stone projectile points provide an opportunity to evaluate how much was the general category of such a point influenced by regional and local factors. The aim of this paper is to explore shape and size variation of Central European Bell Beaker projectile points from Moravia (Czech Republic) to elucidate factors responsible for this variation. The sample consists of 194 projectile points from 54 Central European Bell Beaker sites (2500–2300/2200 BC) distributed in Morava River catchment. The size and shape of projectile points were studied by landmark-based geometric morphometrics and expressed as shape groups, which have been assessed in terms of their spatial distribution, raw material, and reutilization. Although several shape categories of points were identified, there is a strong degree of uniformity in the research sample. The dominant shape category (75.4 % of points) was pervasive across geographic space and was not significantly affected either by raw material or reutilization. A lower degree of reutilization of points is interpreted as a consequence of a non-utilitarian role of projectile points, which represented a critical component of Bell Beaker mortuary practices. 相似文献