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31.
We investigated the decline of a pedunculate oak (Quercus robur L.) forest growing on shallow soil at the northern distributional limit of the species in southern Finland, using the dendroclimatic approach. About 200-year-old trees in three vigour classes — healthy, declining and dead — were sampled in 2008. Annual tree-ring, earlywood and latewood widths were measured and chronologies were established. The tree-ring data were correlated with monthly and seasonal climate data. Radial increment of oaks was positively related to the June and July precipitations. This was expressed especially in total ring width and latewood width, whereas the earlywood was more influenced by the warmer winter and spring. Furthermore, the correlation between the current year earlywood width and the preceding year latewood width was higher than between the earlywood and latewood of the same year. The analyses showed that the dead oaks and part of the declining oaks had ceased growing during 2005–2007 after a decadelong summer drought series. This indicates a time lag in the oak dieback. The radial growth of the declining and the dead oaks had dropped already since the 1990s, while the healthy oaks had better longterm growth and higher adaptive capacity to climate variation.  相似文献   
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Archaeological and literary sources indicate that the ancient Greeks relied heavily on terrestrial resources and that their access to certain types of foods varied by sex and status. Human and faunal remains from the Greek colonial site of Apollonia (5th to 2nd century BC) on the Black Sea coast of Bulgaria were analyzed for stable carbon and nitrogen isotopes in order to reconstruct the diet of this population, investigate the relative importance of marine vs. terrestrial resources, and explore variations in diet with respect to age, sex, and burial type. The results of this study indicate that the colonists of Apollonia relied on a mixed diet of terrestrial and marine foods, and that there was little or no variation in diet by age, sex, or burial type. The relationship between δ13C and δ15N data for these samples suggests that while marine foods were an important source of nitrogen, much of the carbon used to construct amino acids came from terrestrial foods.  相似文献   
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Voted top new Japanese word of 2008, “arafô”, abbreviated from the English “around forty”, has been used in various media to describe women born between 1964 and 1973, who came of age during Japan's Bubble Era, and who entered the workforce as the country's Equal Employment Opportunity Lawwas being implemented in 1986. Arafô, or “forty-something women”, theoretically have more choices in relation to work and family than previous generations. During a time when society is ageing, their choices in employment, marriage and childbirth have been judged in journalistic and government discourses to be both progressive and problematic. At the same time, arafô have been associated with difficulties regarding individual freedom in the spate of television programs, books and magazines for and about them. The term and the gender trends it encapsulates were brought to national attention by the critically acclaimed 2008 television drama Araundo 40: Chûmon no ôi onnatachi (trans. Around 40: Demanding Women). We situate Around 40 in discussions about Japan's demographic crisis to argue that the series presents a wide array of life courses available for women near age 40 but ultimately recasts postwar gender roles for the 21st-century sociopolitical climate. Around 40 shows how the diversification of life courses is interpreted in the influential medium of television drama.  相似文献   
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Roc de Marsal has yielded numerous remains of Mousterian occupations, including lithics, fauna and combustion features. It was made famous by the discovery of the skeleton of a Neanderthal child. Given the need to date the sequence, TL and OSL were applied on heated flints and quartz, and OSL on unheated quartz. Chronological results combined with palaeoenvironmental data – faunal remains and micromorphological features in the sediments from the cave, pollen proxies and faunal remains from the region – allowed us to place climate variations in southwest France on a numerical time scale. Denticulate Mousterian occupations were dated to the middle of MIS 4 (65–70 ka) and Quina layers either to the very end of MIS 4 or to MIS 3. Interestingly, a faunal pattern showing a mix of red deer, roe deer and reindeer was found to have occurred during MIS 4, which was shown to be consistent with data from other similar sites in southwest France.  相似文献   
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There are many examples of buried rock surfaces whose age is of interest to geologists and archaeologists. Luminescence dating is a potential method which can be applied to dating such surfaces; as part of a research project which aims to develop such an approach, the degree of resetting of OSL signals in grains and slices from five different cobbles/boulders collected from a modern beach is investigated. All the rock surfaces are presumed to have been exposed to daylight for a prolonged period of time (weeks to years). Feldspar was identified as the preferred dosimeter because quartz extracts were insensitive. Dose recovery tests using solar simulator and IR diodes on both K-feldspar grains and solid slices taken from the inner parts of the rocks are discussed. Preheat plateau results using surface grains and slices show that significant thermal transfer in naturally bleached samples can be avoided by keeping preheat temperatures low. Equivalent doses from surface K-feldspar grains were highly scattered and much larger than expected (0.02 Gy to >100 Gy), while solid surface slices gave more reproducible small doses (mean = 0.17±0.02 Gy, n = 32). Neither crushing nor partial bleaching were found to be responsible for the large scattered doses from grains, nor did the inevitable contribution from Na-feldspar to the signal from solid slices explain the improved reproducibility in the slices. By modelling the increase of luminescence signal with distance into the rock surface, attenuation factors were derived for two samples. These indicate that, for instance, bleaching at a depth of 2 mm into these samples occurs at about ∼28% of the rate at the surface. We conclude that it should be possible to derive meaningful burial doses of >1 Gy from such cobbles; younger samples would probably require a correction for incomplete bleaching.  相似文献   
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The purpose of the present research is to examine various theories concerning the origin of the Black Death, to record its routes of dissemination in the Nordic countries and across the British Isles, and to compare the pattern of that dissemination with trade routes carrying grain throughout northern Europe in the period up to and including 1350.  相似文献   
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