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91.
Colour plays an eminent role in beadwork. Colour modifications are reported on early shell beads from Middle Stone Age sites. However, identifying the colouring agent and demonstrating the intentional nature of the colouring process is not straightforward. Here, we provide analytical data on colour and structural modifications observed on Nassarius kraussianus (Nk) collected in modern thanatocoenoses and on shells of the same species experimentally heated in oxidizing and reductive atmospheres. Comparison with Nk shell beads from the 72 ka old Middle Stone Age levels of Blombos Cave, South Africa, and contextual analysis of other malacological remains from the same levels that were not used as ornaments identify the mechanisms responsible for the change of colour in modern Nk thanatocoenoses and heated shells, and show that although some Nk shell beads were heated, intentional heat treatment of shell beads is not demonstrated.  相似文献   
92.
Located in the historical center of Catania, Italy, in the Civita district, the Bonajuto Chapel is one of the oldest and best-conserved buildings of the city, which has survived the numerous earthquakes that struck eastern Sicily during the medieval and the modern ages, such as those particularly devastating in 1169 and 1693. However, both the date of this small monument, as well as its original use, still remain uncertain, as literary and documentary evidence are scarce and fragmentary. Most historians, analyzing prevalently the stylistic and constructive aspects, interpreted the chapel as a place of worship and assigned its construction to a rather long period of the early Middle Ages, from the 5th or 6th centuries ad to the 8th or 9th centuries ad—the phase during which the island was under the Byzantine domination. The excavations carried out in 1930 to 1939 and the last restoration works (in 2003) have not provided explicit chronological data. Its age determination is considered essential for a better knowledge of the real influence of this domination on the architecture of the Island. Therefore, a multidisciplinary and accurate analysis of the building using the existing bibliography has been carried out also in order to understand the functional and morphological transformations of the chapel during its long life. The thermoluminescence absolute dating methodology applied to some brickwork elements of the construction, has placed the monument chronology in a period of time that is notably shorter than that previously noted here. These new data, with the study of the architectural structure, have made a significant step forward in the knowledge of the chapel history.  相似文献   
93.
This study characterizes the opacifiers and colouring agents used in the glazed bricks of Persepolis (mid‐first millennium bc ) and the Mannean site of Tepe Rabat in north‐western Iran (eighth to seventh centuries bc ). Various analytical studies show that lead antimonate and brizziite (NaSbO3) were used as the yellow and white opacifiers in the glazes of Persepolis and Tepe Rabat. Brizziite is shown to be incorporated in the white, green and turquoise glazes, and is also associated with lead antimonate and CaSb2O6 in some yellow and white opacifiers. The simultaneous formation of these opacifiers in one glaze might have been accidental. A possible connection between the Achaemenid glaze industry and the Mannean glaze production at Tepe Rabat is discussed.  相似文献   
94.
This paper presents the results of analyses carried out on three decorative phases of the presbytery of the church of Santa Maria Antiqua al Foro Romano in Rome: the fourth‐century ad mosaics setting bed; the Adoration of the Cross, dated to the papacy of John VII (ad 705–7); and the paintings in the apse of the Pope Paul I (ad 757–68) phase. The research allowed the characterization of the painting techniques, pigments, organic compounds and degradation products by means of a video microscope, optical microscopy, and μ‐Raman and FT–IR spectroscopy, contributing to a better understanding of the changes in the techniques and materials used throughout the centuries in one of the most relevant medieval Christian monuments in Western Europe.  相似文献   
95.
马家塬战国墓地是研究西戎文化以及秦戎文化交流的重要考古遗址。在M21墓葬发现了一些附着于铁器表面的矿化纺织品残片。这些矿物外壳保留了比较完整的纺织品形态,是研究早期纺织技术的宝贵资料。为此,本研究采用扫描电子显微镜(SEM)和高效液相色谱-质谱联用技术(HPLC-MS)对矿物纺织品残片的纤维原料进行了鉴定与分析:1)矿物外壳内部的纤维空洞结构形态与桑蚕丝的纤维形态特征相同;2)样品中检出了3组蚕丝蛋白的特征多肽片段。研究结果表明,M21墓葬中的纺织品残片的原料为蚕丝纤维(Bombyx mori)。丝绸的发现表明中原的丝绸成品或者纤维原料已经进入西戎地区,西戎与中原文明的交流更加密切。使用丝绸包裹铁器则表明西戎文化已经受到了一些中原风俗的影响。这一发现填补了马家塬遗址中纺织品研究的空白,不仅为研究秦戎地区的织造工艺和文化交流提供了重要资料,也为矿化纺织遗存中的桑蚕丝残留的鉴定提供了技术支持。  相似文献   
96.
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   
97.
This paper presents research into the identification of tobacco residues in ancient smoking pipes. Two techniques have been used so far: gas chromatography/mass spectroscopy (GC/MS), and Raman microscopy. GC/MS has been used successful in the past by the author to identify ancient tobacco residues, and the results of this round of analysis support prior research. Raman microscopy, which has the advantage of working on dry samples without solvents, was not successful. It appears that combustion products overwhelm any useful signal that would identify the substance smoked. We are pursuing the use of Raman in non-combusted samples.  相似文献   
98.
99.
本文利用拉曼光谱(Raman)、X射线衍射(XRD)和X射线荧光光谱(XRF)等方法,分析了青海省化隆县纳卡遗址出土的马家窑文化及齐家文化彩陶。结果显示:马家窑文化黑彩在不同文化阶段其显色机理不同,半山阶段黑彩以磁铁矿及黑锰矿为主,且Fe/Mn比值较低,反射率最低,呈现浓翠的黑色;而马厂阶段黑彩则以赤铁矿及黑锰矿为主,Fe/Mn比值较高,反射率偏高,主波长为400~450nm,呈偏紫色的黑彩。表明马家窑文化陶工已认识到赤铁矿与黑锰矿的混合矿物颜料、含锰磁铁矿二者之间具有不同的呈色性能,并且熟练掌握了浓淡的变换规律,使之满足于彩绘的需求。齐家文化黑彩以磁铁矿为主,含有锐钛矿,主波长为650~700nm,呈偏红黄色的黑彩,表明这个阶段彩陶的烧制温度不高,彩陶文化已趋向衰落。  相似文献   
100.
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   
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