拉曼原理及特点和应用.ppt

* Stream Line － 高速大面积扫描拉曼成像 161201 个数据，只需94分钟. 平均每个光谱采集时间0.035秒 高速度 ＋ 高空间分辨率 案例 – 交叉笔划，判断书写顺序 化学计量学（统计定量） - Chemometrix M=aX1+bX2+cX3… 低频拉曼测试 – NExT Filter Mercury (II) chloride (HgCl2) 633 nm excitation Imaging - 拉曼光谱直接成像技术 Raman spectrum of sulphur with 1064 nm laser excitation 大样品附件 - Macro Point Sampling Kit * * * * spectrum of orpiment taken in situ from a Persian Shahanama. orpiment degrades to grey on exposure to light so this manuscript cannot go on long term exhibition now we know that it is there. Orpiment was also used to dye pages in a lot of oriental material -- seems to have anti-bug properties as well as being yellow. The manuscript belongs to the British Library so the presence of orpiment also has to be considered when making it available to readers since it contains arsenic. The process involves applying egg tempera paint onto a thin silver foil which lies on a base of brown imprimatura (ochre) and white ground (gypsum). The final layer is a protective varnish. Extensive restoration has occurred in the past to repair cracks in the varnish and the paint layer. Raman has been used to identify the original pigments and the materials used in subsequent restoration Lead white was used as the white pigment in works of art from days of antiquity to the early 20th century lead white is also known as basic lead carbonate parts of the icon have been subjected to restoration as can be seen from the substantial contrast in fluorescence emission between the original and restored areas - eg the left cross Renishaw plc * Confidential Renishaw plc * Confidential Image of a sectioned tooth with 785nm excitation Renishaw plc * Confidential Image of a tooth section with 785nm excitation. Map is composite of two images, generated with differing polarisation geometries. Renishaw plc * Confidential Images of a sectioned tooth with 785nm excitation Renishaw plc * Confidential Image of a cheek cell collected with 532nm excitation. Cells are scraped from