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71.
Ten years ago, I summarized hypotheses for the abundance of bird wing elements in archaeological sites and rejected the hypothesis that differential preservation caused this pattern in the Pacific Northwest Coast (Bovy, 2002). I also noted that distal wing elements (relative to proximal wings) dominated several assemblages in the Gulf of Georgia sub-region. I re-examine this issue, focusing on behavioral hypotheses for the abundance of distal wings. Ethnographic evidence is used to formulate predictions for the cultural explanations, which are tested using data from the late Holocene Watmough Bay (45SJ280) site, where distal wings comprise 98% of the large duck assemblage (n = 4195). Diving ducks, dabbling ducks, geese, loons and grebes all have more distal wing bones than expected, and were likely caught using submerged nets. The most plausible explanation for the prevalence of distal wing bones is either that only the distal wings were transported back to the sites (perhaps attached to skins) and/or the distal wings were discarded separately during cooking.  相似文献   
72.
Black drink is a native North American caffeinated tea produced from the leaves of Ilex vomitoria. The beverage was an important part of prehistoric Southeastern culture, as it was the only native source of caffeine in North America. The leaves of I. vomitoria were, therefore, a potentially valuable trade resource during the period. As such, the ability to identify archaeological black drink residues is useful to Southeastern archaeologists. In order to determine the plausibility of detecting I. vomitoria in residues, black drink was repeatedly produced in experimental unglazed pottery. The resulting potsherds were buried in several environmental contexts, recovered, and underwent absorbed pottery residue analysis. After two months of burial in three different soil types, plus a control stored in the freezer, caffeine was well-preserved in all sherds, suggesting that caffeine is a potentially useful biomarker for the detection of black drink.  相似文献   
73.
A new robust design methodology to control the seismic performance of asymmetric structures equipped with a Single Tuned Mass Damper (STMD) is presented in this article. This design approach aims to control the seismic response of such systems by reducing both flexible-and stiff-edge maximum displacement. The dynamic problem has been investigated in the state space representation showing that the TMD works as a closed-loop feedback control action. A synthetic index to estimate the seismic performance of the main system has been defined by using H norm. Wide-ranging parametric numerical experimentation has been carried out to obtain design formulae for the STMD in order to minimize such a performance index. These formulae allow for a simple design of STMD position and stiffness to optimally control both translational and rotational motion components, whereas two mass devices are generally considered to improve the seismic performance of asymmetric structural systems The effectiveness and efficiency of the obtained design formulae have been tested by investigating the dynamic behavior of the asymmetric structure after being subjected to different recorded seismic inputs.  相似文献   
74.
An approach to mitigate the seismic risk of existing structures by means of the creation of a continuous thin layer of grouted soil at a convenient depth is presented. A parametric numerical analysis is reported using different constitutive models with reference to two geometrical schemes. It is shown that if the grouted layer has a stiffness significantly lower than that of the surrounding soil, it may be effective in reducing the seismic demand. In the parametric analyses, the positive role of yielding is also observed, which indicates that the barrier is more effective with larger input amplitudes.  相似文献   
75.
Tuned mass dampers (TMDs) are effective structural vibration control devices. However, very little research is available on the experimental investigation of TMDs and their performance in systems undergoing dynamic soil-structure interaction. Geotechnical centrifuge tests are conducted to investigate story positioning effects of single and multiple TMDs in a soil-MDOF-structure system. The criteria for optimal story positioning will be established, and it is shown that story positioning influences TMD performance more than the number of TMDs used. Non-optimal story positioning was found to have the potential of reducing damping efficiency, amplifying peak structural response, and inducing lengthier high-intensity motion.  相似文献   
76.
Ancient preserved molecules offer the opportunity of gaining a deeper knowledge on their biological past. However, the development of a proteomic workflow remains a challenge. The analysis of fossils must involve a low quantity of material to avoid damaging the samples. In this study an enhanced proteomic protocol was applied to 5-milligram samples of about 130,000-year-old mammalian bones ranging from the end of the Middle Pleistocene up to the earlier Upper Pleistocene, excavated from Scladina Cave (Sclayn, Belgium). Using sequence homology with modern sequences, a biological classification was successfully achieved and the associated taxonomic ranks to each bone were identified consistently with the information gained from osteomorphological studies and palaeoenvironmental and palaeodietary data. Amino acid substitutions on collagens were identified, thus providing new information on extinct species sequences and helping in taxonomy-based clustering. Considering samples with no osteomorphological information, such as two fragments of bone retouchers, proteomics successfully identified the families providing paleontologists new information on these objects. Combining osteomorphology studies and amino acid variations identified by proteomics, one of the retouchers was potentially identified as belonging to the Ursus spelaeus species.  相似文献   
77.
This paper presents a gas chromatography-mass spectrometry (GC-MS) organic residue analysis (ORA) of samples extracted from five Early Bronze Age ceramic bottles excavated at the archaeological site of Küllüoba in Anatolia (modern Turkey), and the first attempt at directly analysing the content of this category of products. Our results show that various types of liquid have been contained in different bottles and identify the presence of dicarboxylic and oleic acids with a large amount of palmitic acid in most samples, suggesting that they may have mostly contained a plant-based oil. The presence of diterpenoids further shows the addition of ingredients such as conifer resin and other plant-derived products. Overall, the analytical results presented here indicate the exchange of scented oils in Anatolia already during the late third millennium BCE. The different organic residue profiles contained in different samples also suggest a range of different recipes for these products.  相似文献   
78.
Here, we report the physico‐chemical characterization of wall paintings from the Petros and Paulos church in Ethiopia. This work represents the first technical study of paintings located in Ethiopia, rather than paintings in museum collections outside the country, using diverse analytical techniques. In situ examination with a portable X‐ray fluorescence spectrometer (pXRF) was followed by analysis of samples using optical microscopy (OM), scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy (SEM/EDS), micro‐Raman spectroscopy (MRS), attenuated total reflection – Fourier transform infrared spectroscopy (ATR‐FT–IR), X‐ray powder diffraction (XRD) and pyrolysis gas chromatography – mass spectrometry (Py‐GC/MS). The paint stratigraphy, the compositions of the support material, the preparatory and painting layers were studied, as well as the morphology of the pigment particles. The results revealed the use of earth pigments and carbon black. The preparatory layer was uncommon; composed of dolomite, clay rich in clinochlore and sand, in contrast to the more common gypsum and calcite. The binder and the stratigraphic analyses suggested a distempera technique.  相似文献   
79.
This article focuses on the development of the tobacco industry in Iran during the seventeenth and eighteenth centuries. It uses this discussion as an entry point to inquire about the early modern Iranian economy. Using a wide range of primary and secondary sources, it makes several historiographical interventions. In explaining what the development of a completely new agrarian industry means in Iranian society, the paper suggests that innovation and intensification may not have been completely absent in agriculture and that in contrast to the way some of the available literature tends to argue, the Iranian economy may not have experienced continuous decline in all sectors throughout the seventeenth and eighteenth centuries. In addition, this article contends that the tobacco industry helped bring about the rise of merchants and landowners in Iranian society, and with that the further development of mass consumption and ever-increasing cycles of production and accumulation that expanded the commercialization of agriculture, domestic and international trade networks, and Iran's agrarian economy.  相似文献   
80.
Suggestive experts: The rise of American communication studies (1930s to 1950s). – The history of social engineering and its rise in the first half of the twentieth century is a well developed field today. This article attempts to add the history of communications research to this field of historical study. The focus lies on the experts for mass communication and their difficulties to combine scientific methodology with the promise to explore how human behaviour can be influenced by the mass media.  相似文献   
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