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1.
出土青铜酒器残留物分析的尝试   总被引:3,自引:1,他引:2  
利用快速溶剂萃取法,从出土青铜酒器内的土壤中提取有机残留物.对其作高效液相色谱定性分析,发现其中含有酒石酸,表明这些青铜酒器在下葬时可能盛着酒。快速溶剂萃取法的萃取剂为1%磷酸(体积比)溶液,较之传统有机溶剂,操作时更为方便和安全。此方法可推广于陶器中残留物的分析.具有较为广泛的应用前景。  相似文献   
2.
依据现代科学检测方法,对唐代鎏金铜天王像不同部位的锈蚀产物进行了系统分析。运用软硬酸碱之间相互反应规律的理论,制定了以EDTA为主的配位体参加除锈反应的方案。综合多年的工作经验,找出络合反应中的最佳反应条件,从理论和实践中总结出较为可行的鎏金器物保护方法。  相似文献   
3.
Flemish 15–17th century tapestries are among the most precious testimonies of European cultural heritage. Even in their deteriorated condition, they are still highly valued and exhibited in many museums all over the world. The present state of degradation evidenced by visual assessment in conservation practice, and confirmed with macro-scaled tensile strength tests, reveals the vulnerability of the wool and silk fibres to light exposure.  相似文献   
4.
D. BROSETA  N. TONNET  V. SHAH 《Geofluids》2012,12(4):280-294
The various modes of acid gas storage in aquifers, namely structural, residual, and local capillary trapping, are effective only if the rock remains water‐wet. This paper reports an evaluation, by means of the captive‐bubble method, of the water‐wet character in presence of dense acid gases (CO2, H2S) of typical rock‐forming minerals such as mica, quartz, calcite, and of a carbonate‐rich rock sampled from the caprock of a CO2 storage reservoir in the South‐West of France. The method, which is improved from that previously implemented with similar systems by Chiquet et al. (Geofluids 2007; 7 : 112), allows the advancing and receding contact angles, as well as the adhesion behavior of the acid gas on the mineral substrate, to be evaluated over a large range of temperatures (up to 140°C), pressures (up to 150 bar), and brine salinities (up to NaCl saturation) representative of various geological storage conditions. The water‐receding (or gas‐advancing) angle that controls structural and local capillary trapping is observed to be not significantly altered in the presence of dense CO2 or H2S. In contrast, some alteration of the water‐advancing (or gas‐receding) angle involved in residual trapping is observed, along with acid gas adhesion, particularly on mica. A spectacular wettability reversal is even observed with mica and liquid H2S. These results complement other recent observations on similar systems and present analogies with the wetting behavior of crude oil/brine/mineral systems, which has been thoroughly studied over the past decades. An insight is given into the interfacial forces that govern wettability in acid gas‐bearing aquifers, and the consequences for acid gas geological storage are discussed along with open questions for future work.  相似文献   
5.
The mycobacterial cell wall is consists of several long chain lipid and glycolipid components. Mycolic acids are major and unique fraction of the cell envelope of mycobacteria that include the ancient causative agents of tuberculosis and leprosy. The analytical investigation of these lipid biomarker residues is one of the most promising perspectives in the field of molecular paleopathology. Recently published in this journal, Minnikin et al. present a systematic critique of the MALDI TOF MS analysis for determination of ancient mycolic acids, focusing on our previous paper. In this study, our mass spectrometric investigations by commonly used 2,5 DHB matrix were presented with our comments to the critique authors. On the base of our previous and recent mass spectrometric results we have to realize that the clinical protocols and standards cannot directly be used for the biomolecular paleopathological investigations. The applicability of the recent mycobacterial and clinical results is very limited in the biomolecular archaeology, thus the recent scientific results and protocols should be adapted carefully to bioarchaeological sciences.  相似文献   
6.
ABSTRACT

There are growing concerns in South Africa about the threat that acid mine drainage (AMD) poses to local natural water resources in many of the country's mining areas. Since the beginning of the 21st century, the toxic water has been responsible for pollution in parts of the country. Government and operators in the country's water sector have actively been working in recent years at addressing the problem. This article deals with a contemporary history of an AMD crisis in the coalmining town of Carolina, in the Mpumalanga Province of South Africa, and explains how the matter was eventually resolved. The discourse focuses on how people of Carolina responded to the contamination of the municipality's water supply system and eventually chose to follow the path of active protest. The water crisis even made a detour to the high court, with a number of non-governmental organisations (NGOs) actively supporting the cause of local residents. Although by September 2012 the town's water supply was restored, the community remained distrustful of the local authority's ability to secure a consistent supply of good quality water. The authorities took some measures to restore trust. People had been traumatised and sound relations had to be restored in the aftermath of the crisis. The Carolina crisis of 2012 is contemplated from the perspective of the current threat that AMD poses to South Africa's finite water resources and the danger of mining in sensitive areas.  相似文献   
7.
Accurate reconstruction of diagenetic P‐T conditions in petroleum reservoirs from fluid inclusion data relies on valid measurements of methane concentration in aqueous inclusions. Techniques have been developed (Raman spectrometry) to provide sufficiently accurate data, assuming measured methane concentration has not been modified after aqueous inclusion entrapment. This study investigates the likelihood that organic acids derived from petroleum fluids and dissolved in formation water might suffer decarboxylation upon postentrapment heating within the fluid inclusion chamber, thereby generating excess CH4 in the inclusions. Four different experiments were conducted in fused silica capillary capsules (FSCCs), mimicking fluid inclusions. The capsules were loaded with acetic (CH3COOH) or formic (HCOOH) acid solution and were heated to 250°C for short durations (<72 h) in closed‐system conditions, with or without applying a fixed PH2. Reaction products were characterized by Raman and FT‐IR spectrometry. Results indicate that decarboxylation reactions did take place, at variable degrees of progress, and that measurable excess CH4 was produced in one experiment using acetic acid. This suggests that methane may be produced from dissolved organic acids in natural aqueous inclusions in specific situations, possibly inducing errors in the thermodynamic interpretation.  相似文献   
8.
An alabaster lid with a resinous accretion burnt or stuck next to the handle and on the base was uncovered in the Nabataean rest stop in Moyat Aawad (Moa) in the Arava valley in Israel. The analysis of this resin sample utilising GC‐MS revealed several types of compounds. The chemical analysis revealed compounds typically present in pine tar and plant lipid material (probably oil). The use of pine resin, tar and pitch derived from plant resins is documented in antiquity, not only as a sealant or caulking material but also as medicines, antiseptics and ritual balms.  相似文献   
9.
The identification of the organic residues preserved in archaeological materials yields good insights into understanding food production, trade and consumption. Wine is one of the most important beverages produced, traded and consumed in the Mediterranean area. Consequently, it is important to identify its presence in ancient materials. Nevertheless, the identification of wine markers is still an object of discussion. We present here the results obtained from analysing different materials using gas chromatography/mass spectrometry (GC/MS), which allowed for the identification of tartaric acid and other markers of wine. The method was first tested on experimental and traditional materials that have been used until recently to store and/or produce wine and was then used for investigating archaeological materials. The experiments also involved the degradation of wine through cooking, drastic heating and burial for seven years. The results from the analysis of ceramic and plaster materials are discussed.  相似文献   
10.
Archaeological studies including stable carbon and nitrogen isotope analyses of bone collagen from human remains have suggested their heavy dependence on terrestrial foods during the Jomon period in the inland central region in Japan. However, it is not easy to quantitatively evaluate the extent of carnivory for archaeological human remains based on the bulk collagen chemistry, because of variable 15N-enrichment factor along the trophic step and background isotopic variations in ecosystems. In order to overcome these problems and more precisely evaluate diets of prehistoric humans who strongly adapted to terrestrial environment, in this study we applied nitrogen isotope analysis of individual amino acids in bone collagen to two inland human populations in the Jomon period. Our results suggest that the two populations were predominantly dependent on the C3-plant-based terrestrial ecosystem and consumed little aquatic resources. Furthermore, their mean trophic positions (2.7 for both cases) are closer to that of the fox (2.8–3.0) rather than those of pure herbivores (2.0–2.2), and show little change over time. These results are the first evidence that inland Jomon populations may have had more carnivorous diets than is traditionally considered.  相似文献   
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