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51.
Wall paintings from the Islamic epoch (10th to 12th centuries) and the Christian monarchy (14th to 16th centuries) have been recovered in discarded materials and on walls after reconstruction works in the Seville Alcazar. These paintings have spent centuries underground or under a plaster coat. Portable X‐ray fluorescence (XRF) and combined XRF/X‐ray diffraction (XRD) were employed in situ, as well as scanning electron microscopy (SEM–EDX), grazing angle incidence XRD and micro‐Raman spectroscopy, on cross‐section samples to fully characterize the materials in the wall paintings. Using these methods, the fresco technique was demonstrated, and many kinds of pigments were identified in accordance with the various periods of the history of the Alcazar, thus assessing the authenticity of all the wall paintings studied here.  相似文献   
52.
Ancient masonry structures are often damaged by soluble salt crystallization, which is activated by even small microclimatic variations. Unsuitable environmental conditions can accelerate this process, affecting the type and the quantity of salts and the consequent damage to the masonry. Therefore the importance of monitoring salt diffusion to control salt crystallization and microclimate over time is widely recognized. This study proposes an integrated monitoring methodology to obtain information on the relationship between salt efflorescence and microclimate in the Crypt of the Duomo of Lecce (South Italy). By combining ion chromatography, powder X-ray diffraction analysis, and Raman microscopy with environmental monitoring and deterioration maps, salt components were identified and efflorescence diffusion on masonry was monitored over time. Due to this approach, a possible explanation for the process is finally given.  相似文献   
53.
A study was made of the degradation of archaeological Scots pine (Pinus sylvestris L.) at the Iron Age archaeological site of Biskupin, Poland. Wood degradation was evaluated after 10 years of deposition of samples in different burial conditions (mineral soil, peat and water) and at different depths (25, 50 and 100 cm) at the location of the original archaeological wood from the Lusatian culture settlement. Changes in the wood samples were assessed on the basis of selected physical (maximum water content, basic density and porosity) and chemical (chemical composition, structure of cellulose and lignin) properties. The observed degradative changes were different for samples deposited in different locations of the archaeological site and at different depths. They relate mainly to carbohydrates—both cellulose and hemicelluloses—although the structure of lignin also underwent changes. The experiment using wood that had been degraded to a similar degree to the Biskupin wood enabled identification of the actual danger of degradation of the latter. It was found that the remains of the wooden structure of the Biskupin settlement are degrading, despite the favourable physicochemical conditions prevailing at the site, and it is necessary to take measures to prevent its further decomposition.  相似文献   
54.
Perfumes embody a chemical record of style and technology. Blurring the boundary between what counts as natural and artificial in both a material and a perceptual sense, perfumery presents us with a domain of multiple disciplinary identities relevant to social studies: art, craft, and techno-science. Despite its profound impact as a cultural practice, perfume has seldom featured in historical scholarship. The reason for this neglect is its inherently qualitative dimension: perfume cannot be understood via codified representation but requires direct acquaintance with its sensory and material basis. The historical study of perfumery thus necessitates an experimental approach that comes not without challenge. This article looks at contemporary recreations of old perfumes to identify the difficulties involved in the experimental recreation of fragrances as sensory and performative artifacts. We highlight the need for a reconceptualization of methodology for inconcrete objects of study as part of the broader interest in experimental approaches to the humanities.  相似文献   
55.
作为人类文化遗产的重要组成部分,古旧木材保存状态的评价及保护至关重要。为了推进对古木材保存评价的深入研究,通过对多参数检测(微形态学、物理学、化学)在微观尺度下评价古旧木材保存状况及腐蚀机理的研究成果进行了综述,在介绍了从木材细胞形态、物理孔隙结构、化学组分含量、分子结构、分子量分布等方面对古旧木材进行评价的基础上,较为全面地阐述了检测各参数的不同表征方法,包括扫描电镜法、氮气吸附法、高效液相色谱法、气相色谱/质谱联用法等,具体分析了不同表征方法间的优缺点,说明了多参数检测古旧木材保存状况的可行性及重要性,并希望以此为切入点探讨古旧木材的宏观力学性能。研究结果在木质文化遗产和历史木构建筑的保护方面具有极大价值。  相似文献   
56.
Employing phenomenological theory, this paper argues that German World War I soldiers’ introduction to the gas mask represents a salient historical moment in the human relationship to modern chemical technology. As a protective device, the gas mask was intended to save soldiers from a horrible death by asphyxiation. In doing so, it forced soldiers to directly confront the new technological landscape of the modern World War I battlefield. While the mask proved genuinely effective in its ability to filter poison gases, it required constant vigilance from gas-weary soldiers. This so-called ‘gas discipline’ would allow men to survive and even thrive in a newly dangerous modern world. However, the physical and mental stress of this existence, often led to breakdowns in soldier discipline and failures in gas protection. Thus, the soldiers’ relationship to the gas mask revealed the limits of technological trust for the earliest ‘chemical subjects’ of the twentieth century.  相似文献   
57.
This paper is the last in a series presenting geochemical analyses of fragments of bituminous mixtures excavated from archaeological sites in Kuwait. The first was devoted to bituminous boat remains from the Ubaid‐related Neolithic site of H3, As‐Sabiyah, while the second dealt with bituminous amalgams from the Partho‐Sasanian site of cAkkaz, a former island now joined to the south side of Kuwait Bay. This, the third, refers to bitumen‐bearing samples from two other islands, Failaka and Umm an‐Namel, and covers a time span including the Early Dilmun period, the Kassite period and the Hellenistic to Early Islamic periods. The composition of the bituminous amalgams was studied in detail. The proportions of soluble and insoluble organic matter as well as vegetal organic matter were evaluated. Mineralogical composition by X‐Ray diffraction and thin‐section analysis was used to estimate the mineral input in the bituminous mixtures. It can be confirmed that the recipes used in the preparation of these bituminous amalgams comply with those traditionally used in antiquity, as seen at many sites in Mesopotamia and the Gulf. Analysis of the soluble organic matter, and especially its ‘‘saturates’’ fraction, provided sterane and terpane distributions and the measurement of diagnostic molecular ratios. These data, complemented by the isotopic composition of asphaltenes, allowed the identification of the sources of the bitumen, by calibration with numerous references from Iran and northern Iraq (oil seeps, bitumen from archaeological sites). It was established that the bitumen from Failaka and Umm an‐Namel was mainly imported from central Iraq (Hit‐Abu Jir) and northern Iraq (around Mosul). One sample of oil‐stained sand, dating to the Early Dilmun period, originated from Burgan and thus documents small‐scale imports from inland Kuwait. These results, and those of previous analyses, agree with the geopolitical context of the Early Dilmun, Kassite and Hellenistic periods, and the maritime trade routes that linked Mesopotamia to the settlements of the Gulf and beyond. The paper concludes with an overview of recent bitumen provenance analyses, and discerns chronological patterns in the distribution of Iraqi and Iranian bitumen in the Gulf and Indian Ocean, from the Neolithic to the Islamic periods.  相似文献   
58.
化学材料在南通天宁寺古建筑维修中的应用   总被引:3,自引:0,他引:3  
天宁寺是江苏省重点文物保护单位,该建筑历经千年风霜雨雪,虫蛀霉烂,残损情况十分严重。本文简要分析了古建筑的落架大修与化学加固两种方案的利弊得失,重点介绍了化学材料在木构古建筑维修、加固中的应用。  相似文献   
59.
人地关系系统及其调控   总被引:5,自引:0,他引:5  
左伟  周慧珍  李硕  李伟 《人文地理》2001,16(1):67-70
论述了可持续发展与人地关系系统调控的关系。在系统理论的指导下,分析了人地关系系统的基本特征和人地化学元素同构特性;给出了人地关系调控的理论思路。  相似文献   
60.
The effects of biodegradation and heating on the stable carbon, nitrogen, hydrogen and oxygen isotope ratios of chitin in arthropods were studied. Chitinous exoskeletons from seven aquatic arthropod species were subjected to anaerobic marine biodegradation in mud, to terrestrial biodegradation in soils, and to thermal degradation under anaerobic and aerobic conditions. The isotope ratios of chromatographically separated D-glucosamine hydrochloride and derivatives from treated and untreated specimens were then compared. Carbon, nitrogen, oxygen and hydrogen stable isotope ratios were all found to be conserved during partial degradation of chitin. Micromorphological comparative studies using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that no fungal chitin or other contaminants were present in the chitins that were chemically isolated from biodegraded substrates. Our results indicate that it will be possible to use stable isotope ratios of archaeological chitin samples for environmental and climatic reconstructions. An illustration of the utility of this approach comes from the observation that the stable isotope ratios of chitin from crustacean exoskeletons recovered from archaeological sites with ages up to 1400 years bp are in good agreement with measurements on modern crustaceans from similar environments.  相似文献   
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