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排序方式: 共有54条查询结果,搜索用时 15 毫秒
41.
PVC食品包装膜中增塑剂DEHA的测定   总被引:7,自引:0,他引:7  
利用ATR技术测定样品的红外光谱,采用偏最小二乘法对所测的红外谱图进行分析,建立了一种无损快速分析方法,定量测定了PVC食品包装膜中增塑剂DEHA的含量。结果表明,标准曲线线性关系良好,相关系数为0.9999。该方法不受基体的干扰,结果可靠,简单快速,适合于流水线的质量控制。  相似文献   
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用酸碱滴定法和络合滴定法对海螵蛸、瓦楞子、龙骨中的钙含量进行了测定,并做出其红外光谱与纯CaCO3的红外光谱进行比较.  相似文献   
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通过对襄渝铁路二线财神庙隧道施工过程中出现的不明气体,利用FTIR光谱进行分析,介绍红外光谱分析方法的产生、原理和优点.同时对隧道内的施工钻孔逸出的不明气体和隧道内的空气二者的红外光谱进行对比分析.  相似文献   
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none 《文物保护研究》2013,58(2):92-105
Abstract

The painting materials used by Lucio Fontana were investigated through the analysis of 28 Spatial Concept works created between the early 1950s and the artist's death in 1968. The pictorial media were analyzed by means of numerous techniques including Fourier transform infrared spectroscopy, pyrolysis-gas chromatography–mass spectrometry, scanning electron microscopy, and X-ray fluorescence. This study has provided a more complete understanding of the artist's technique, as it was found that Lucio Fontana had already begun experimenting with new synthetic pictorial and binding media such as alkyds and polyvinyl acetates at the beginning of the 1950s, and polyesters during the early 1960s. Although he never abandoned the use of commercial oil paints, Fontana's application of these new materials continued in an infinitely varied search for innovative expressive effects. The characterization results explain the physical and mechanical properties of the paint layers, and may be correlated with the conservation state of the works analyzed. All the results have been compiled and are discussed together with the artist's practices and their evolution over time.  相似文献   
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The Scuola Grande di San Marco is one of the most outstanding Renaissance buildings in Venice. Destroyed by fire in 1485, the Scuola was reconstructed between 1487 and 1495 by Pietro Lombardi (and sons), together with Giovanni Buora and Mauro Codussi. The façade is considered one of the finest and most original exteriors of Venetian buildings and in particular features refined sculptural and painted decorations and a remarkable pictorial effect created by the extensive use of polychrome marbles and the false perspective view between the pilasters of the lower order. Most of the stone materials (Istrian and Verona red limestones, nero di Roveré, pavonazzetto toscano, Carrara marble and various reused antique marbles) present evident decay phenomena such as scaling, exfoliation, powdering, fissuring, salt efflorescence, black crusts, and artificial patinas of various kinds. The present study reports the results of petrographic and chemical laboratory analyses carried out in preparation for the conservation treatment of the building, in order to characterize the main micro- and macro-morphologies of decay and to identify the causes and mechanisms of deterioration as well as the nature and application technique of the polychromy, gilding, and patinas present on parts of the monumental Renaissance façade.  相似文献   
48.
从分子水平研究了PEO-PPO-PEO嵌段共聚物聚集过程中分子基团微环境和构象的变化。FTIR光谱给出了温度、溶剂、嵌段共聚物组成等影响PEO-PPO-PEO嵌段共聚物胶团结构的定量信息。用无机盐和脂肪醇调控PEO-PPO-PEO嵌段共聚物聚集,荧光光谱技术提供了降低PPO链段与水的相互作用,推动嵌段共聚物在水中胶团化的证据。用水凝胶包埋PEO-PPO-PEO嵌段共聚物,实现了萃取水中低浓度多环芳烃的工艺循环。  相似文献   
49.
Analysis of historic mortars including Islamic, Gothic and later ones taken from palaces, convents and mansions in Palma de Mallorca has been carried out. Scanning electron microscopy (SEM) coupled to energy dispersive X-ray spectrometer (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) techniques were used to characterise the morphology and analytical composition of the samples analysed. Generally, covering plaster mortars presented a low percentage of small size aggregate. The reported results show that mixed and lime mortars have been used, thus, the establishment of a relationship between the type of mortar employed and its age is not feasible. In the painted mortars, polychromy has also been studied. The most common pigments to be found are natural earths.  相似文献   
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运用傅立叶红外光谱对(胰特敏)和其它几种西药降糖药物进行了指纹图谱分析研究.发现胰特敏和格列本脲红外光谱图有较大的相似性,但是胰特敏和格列齐特、盐酸二甲双胍的指纹图谱有很大的差异存在.综合分析研究后知在胰特敏中可能含有格列本脲.采用此种方法简便可行,无损坏作用且快速,适用性强,可以为该类药物的结构鉴定及质量的监控提供科学依据.实验证明可以用傅立叶红外光谱来初步鉴定中药降糖药物中是否含有两药成分  相似文献   
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