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1.
采用光学显微观察、激光拉曼、紫外-可见吸收光谱以及高效液相色谱对河北隆化鸽子洞蓝棉袄蓝色、浅蓝色纤维以及百衲枕顶蓝色纤维进行分析研究.通过多种分析手段相互佐证表明,该组样品采用蓝草中的靛蓝染色,色素成分有靛蓝素和靛玉红.各样品中色素成分比例均不相同,推测至少在元代,人类已经能够有意识地调整制靛工艺,染出自己需要的色光.同时靛蓝染料耐光性耐热性差,对酸、碱和氧化均敏感,耐盐性及耐细菌性较弱.在以靛蓝染色的织物清洗中,要选择性地使用洗涤剂,进行点滴试验后才可使用,同时在存放过程中要做到避光、避免高温.  相似文献   
2.
丝绸的老化及保护剂的筛选   总被引:3,自引:0,他引:3  
讨论了光和热对丝绸老化的影响。结果表明,光比热对丝绸之染料的影响大得多;随着辐照时间的增加,丝纤维强度降低曲线呈典型的动力学反应特征。通过抗张强度、白度等测试,对保护剂进行了筛选。  相似文献   
3.
An analysis of energy use by Neanderthals in Northern Europe during the mild Eem interglacial period is carried out with consideration of the metabolic energy production required for compensating energy losses during sleep, at daily settlement activities and during hunting expeditions, including transport of food from slain animals back to the settlement. Additional energy sources for heat, security and cooking are derived from fireplaces in the open or within shelters such as caves or huts. The analysis leads to insights not available from archaeological findings that are mostly limited to durable items such as those made of stone: Even during the benign Eem period, Neanderthals faced a considerable heat-loss problem. Wearing tailored clothes or some similar measure was necessary for survival. An animal skin across the shoulder would not have sufficed to survive even average cold winter temperatures and body cooling by convection caused by wind. Clothes and particularly footwear had to be sewn together tightly in order to prevent intrusion of water or snow. The analysis of hunting activity evolvement in real time further shows that during summer warmth, transport of meat back to the base settlement would not be possible without some technique to avoid that the meat rots. The only likely technique is meat drying at the killing site, which indicates further skills in Neanderthal societies that have not been identified by other routes of investigation.  相似文献   
4.
Stable isotope analysis of charred archaeobotanical cereal grains has the potential to provide direct evidence of crop growing conditions in the past and to refine palaeodietary predictions. If isotope values of archaeobotanical material are to be considered robust, it is necessary to characterise the compositional changes associated with their charring and burial. This study used a suite of analytical techniques, including FT-IR and solid state 13C NMR, to characterise changes in the biochemical composition of modern einkorn grains with heating at 230 °C for 2 h, 4 h, 8 h and 24 h, encompassing conditions that replicate their undistorted ancient counterparts. The biochemical composition of archaeobotanical charred einkorn grains was also investigated by FT-IR and solid state 13C NMR in order to assess the changes in composition which occur during burial. Results of FT-IR and solid-state 13C NMR show that heating of modern einkorn grains resulted in Maillard reactions between cereal proteins and starch, forming high molecular weight melanoidins, which contain both alkyl and aromatic carbon. Loss of low molecular weight carbon and nitrogen-containing volatiles resulted in a slight but non-systematic increase in the δ13C values and a systematic increase of 0.8‰ in the δ15N values of the charred einkorn grains. Solid-state 13C NMR shows that the ancient charred einkorn grains consisted entirely of aromatic carbon and retained a similar proportion of nitrogen to their modern 24 h charred counterparts, despite a significantly lower concentration of amino acids. This indicates that the amino acid nitrogen in the ancient charred grains was retained in the stable melanoidins whose polymeric structure makes them resistant to subsequent degradation.  相似文献   
5.
Y. Guan  Z. Y. Zhou  Y. Huan  X. Gao 《Archaeometry》2015,57(6):949-965
The application of heat‐treatment technology on lithic raw materials is an important feature of early modern human behaviour. The evidence of heat‐treated stone artefacts discovered at Localities 2 and 12 of the Shuidonggou Late Palaeolithic site, North‐West China, provides an important example for studying this technology among ancient humans in Asia during the Late Palaeolithic. The mechanism and effects of heat treatment on raw materials and the role of this technology in producing stone tools were studied by means of a simulation experiment and related analytical methods. These facilitated an in‐depth analysis of the heat‐treatment activities of the Shuidonggou occupants and their implications for cognitive ability and survival strategies of human populations at that time.  相似文献   
6.
传统的冷冻脱水过程通常需要将电阻温度传感器(RTD)插入到物料中以监测温度变化从而确定干燥终点,这种方式对于处理木质文物来说具有一定的破坏性,无法做到无损或微损。本研究尝试采用无损方式对定型加固剂浸渍液即时浓度进行分析,并对冷冻干燥终点进行预测。采用这种无损技术成功地对志丹苑元代水闸遗址出土的30件木构件进行真空冷冻脱水定型处理,既达到了预期的定型保护效果,又确保了木构件的安全。  相似文献   
7.
The possibility of determining the human or animal origin of bones from the lattice parameters of their inorganic bioapatite phase, when subjected to a high temperature treatment using the powder X-ray diffraction (XRD) technique, has been explored on a wide number of specimens. Forty-two animal bones were treated in a furnace at 1100 °C for 36 min and compared to 53 cremated human bones from a range of ancient necropolises. The X-ray diffraction patterns of bioapatite were simulated using both monoclinic P21/b and hexagonal P63/m structures to verify any occurrence of phase transformation and any difference in the lattice parameters due to the model. It was determined that the differences between the a-axis and c-axis of the monoclinic and hexagonal lattice were unimportant. Some outlying values were revealed to be caused by the presence of chlorine ions diffused into the apatite structure increasing its average unit cell values. Nevertheless, our results clearly show that in terms of lattice parameters the variability of human specimens are completely overlapped by the non-human variability making the use of XRD in order to distinguish animal from human bones questionable.  相似文献   
8.
As in traditional societies today ancient societies probably selected different fuels to meet specific heat requirements. Char and ash, the end products of fire, are often found in abundance in archaeological contexts. These end products can provide information regarding (i) the original fuel resource and type, (ii) the characteristics of the fire and (iii) combined with other archaeological evidence shed further light on possible socio-economic activity(-ies) associated with that fire. The three main fuel resources would have been (i) modern vegetation, (ii) fossil fuel and (iii) animal by-products. Local availability and abundance would have influenced the choice made.In this study an experimental approach was adopted to try and distinguish between the three different fuel resources that are known to have been used by ancient societies (and continue to be used by traditional societies today) from their char and ash remains to help determine original fuel-type and understand the relative heating properties. For this end one fuel-type from each fuel resource listed above, namely wood, peat and cow dung, was chosen.  相似文献   
9.
Conditions in which thermal fractures occur are explored experimentally, and the results are used to assess heat treatment strategies. We conclude that no single ‘critical temperature’ for thermal fracturing or heat treatment can be specified for any particular raw material, as has so often been attempted, because threshold temperatures exist in relationship to specimen sizes. Our experiments show that smaller specimens are resilient to greater ranges of temperature fluctuations than larger ones, and that by manufacturing/selecting specimens of smaller sizes there is more potential to heat them rapidly and to higher temperatures without producing thermal fractures. We hypothesize a continuum of heat treating strategies between a ‘slow and steady’ strategy, which has overwhelmingly dominated past experimental designs, and a ‘fast’ strategy, which has received much less attention. The paper discusses the economic and technological contexts to which different heat treating strategies might be suited.  相似文献   
10.
At the end of the fifth millennium bc , the development of a specialized lithic industry in the Chassey societies of south‐eastern France and its dissemination as far as Catalonia and Tuscany attest to important socio‐economic changes in the Mediterranean Neolithic societies. The lithic production was made on barremo‐bedoulian flint that was heat‐treated to improve the sharpness of the tools produced. Microscopic observations of archaeological and geological, heated and unheated barremo‐bedoulian flint samples allowed us to highlight the heat‐induced formation of fluid inclusions. Microthermometry analyses showed that these inclusions contain pure H2O, most probably resulting from the dehydration of length‐slow (LS) chalcedony and the closure of narrow pores, according to the model proposed by Schmidt et al. ( 2012 ). Our results enable us to estimate the heating temperatures used by Chassey artisans to ≈ 230°C. We also propose the ‘pressure cooker’ model to explain the migration of liquid water in flint nodules heated to 230°C. Then, we discuss the ability of a particular type of flint to be heat‐treated, and hence its value for Neolithic society, which depends on: (1) the amount of LS chalcedony that ensures the water release at relatively low temperature; and (2) on the total volume of porosity available to store the dehydration water.  相似文献   
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