基于光谱表示和独立成分分析的混合颜料成分分析方法

在混合颜料成分分析中,反射光谱法通过计算相似性来判断基本颜料种类,容易受多种基本颜料的影响,造成分析结果不准确。将光谱表示为信号,结合独立成分分析,提出一种基于光谱表示和独立成分分析的混合颜料成分分析方法。首先,采用光谱仪获取混合颜料光谱信息,并将其表示为离散信号的形式;然后,对信号进行独立成分分析,得到基本颜料的光谱信息;随后,通过计算基本颜料光谱与已知颜料光谱的相似性,确定基本颜料种类;最后,逆用Kubelka-Munk混色公式就可以得出基本颜料的比例。我们采用蒙赛尔色卡光谱制作模拟数据,分别进行正常/扰动情况下三种色卡光谱混合信息的成分分析试验,以及从8种色卡光谱中选择若干种混合后的成分分析实验。分离出的光谱形态与已知的原始颜料光谱形态极其相似,平均相似比为97.72%,最大相似比可以达到99.95%,得出的基本颜料比例与混合时的比例基本相同。实验结果表明本方法适用于混合颜料成分分析。     

西藏拉萨大昭寺转经廊壁画颜料的拉曼光谱分析

利用显微激光拉曼光谱仪对大昭寺转经廊壁画颜料进行了分析。结果表明,壁画使用的红、黄、蓝、绿和白色颜料有朱砂、铅丹、甲苯胺红、雌黄、铅铬黄、铁黄、石青、群青、石绿、水胆矾、巴黎绿、菱镁矿、立德粉和方解石。首次发现壁画中使用了合成有机颜料甲苯胺红。检测分析结果提供了准确可靠的资料,有助于清晰认识不同时期壁画绘制和修复所使用颜料成分。     

拉曼光谱法结合薄层层析分析红酵母色素

利用薄层层析色谱法分离红酵母色素,结果显示,红酵母细胞能合成至少三种色素,即β-胡萝卜素、红酵母红素、圆酵母红素;采集三种色素的拉曼光谱,光谱数据经过背景扣除、基线校正、三点平滑等方法预处理,统计不同色素的平均光谱,结果表明三种色素的CC拉曼位移不同,并且β-胡萝卜素的拉曼位移最多,红酵母红素和圆酵母红素的含量较多;定量分析色素特征峰高比值,各色素峰高比值差异不大,峰高比值能用作参数,为深入研究活体细胞内色素的相对含量提供参考。以上结果表明,拉曼光谱法结合薄层层析能够分析红酵母色素,可以提供红酵母色素的丰富信息,是研究色素的有效方法。     

光导纤维反射光谱技术在彩绘文物颜料无损分析鉴定中的应用

文物颜料成分分析鉴定是文物材质分析和文物保护工作的重要内容。利用自行研制的光导纤维反射光谱仪对唐代彩绘陶器和壁画上的颜料成分进行了无损分析鉴定,通过比较彩绘文物颜料和标准颜料的反射光谱曲线的形状以及特征峰或一阶导数峰来完成颜料的鉴定工作。光导纤维反射光谱法鉴定出西安市唐代彩绘文物1#样品墓葬壁画上的深红色颜料是纯度较高的土红;2#样品陶器残片上的绿色颜料为石绿;3#样品陶缸残片上的橙红色和朱红色颜料分别是由大量铅丹和微量土红及大量朱砂和微量土红的混合物所组成。采用X射线荧光分析法进行验证,实验结果表明光导纤维反射光谱技术鉴定彩绘文物颜料成分的结果是准确、可靠的,提供了一种文物颜料无损分析的简捷方法。     

北魏墓彩绘陶俑颜料的显微拉曼光谱分析

利用拉曼光谱对洛阳地区两座北魏墓出土陶俑的彩绘颜料进行了分析, 与标准颜料样品的拉曼光谱相比较, 识别出了陶俑所使用的红色、黑色、白色和蓝色颜料的显色成分。研究结果表明, 显微拉曼光谱分析技术非常适合对古墓葬彩绘陶俑进行成分分析。     

“钟离君柏”墓出土彩绘陶器颜料的光谱分析

利用拉曼光谱结合X射线衍射物相检测方法,对安徽蚌埠双墩春秋中晚期“钟离君柏”墓出土彩绘陶器颜料的物相结构进行了分析测定。结果表明,陶器表面的红色、黄色和黑色颜料皆保存较好,未发生明显变化,分别是无机矿物朱砂(HgS)和针铁矿(α-FeO(OH))及炭黑。同时,拉曼光谱与X射线衍射分析的结果都显示红色颜料朱砂的组成物相单一,不含天然朱砂的伴生矿物石英,且其晶粒尺寸可能在纳米范围,应是由人工合成或经过古人的加工、纯化处理。针铁矿的发现表明春秋时期该矿物己被用作黄色颜料,这是目前己知的针铁矿作为黄颜料使用的最早的实例。     

Colour and art: A brief history of pigments

Human beings have had an inherent urge to leave their mark in the form of works of art since prehistoric times. This has driven the quest for new and better pigments with which to make paints. This paper describes the origins and composition of earliest earth pigments used by primitive man to decorate the walls of caves through to the synthetic pigments developed in more recent times. Despite modern technology, the artist's palette remains a mixture of the pigments used by cave artists, natural pigments used in the middle ages, and modern organic compounds.     

油画“穿着晚礼服的女士”XRF的全域成分分析

使用X射线荧光光谱分析仪研究了创作于1955年的油画作品“穿着晚礼服的女士”中的全域颜料的成分分布,分析了该油画颜料的材料信息。这幅创作于20世纪中叶的油画依然主要采用矿物质颜料,同时也有少量区域开始采用有机颜料,部分部位的油画颜料为作者自己配制的非标准油画颜料。油画由于其艺术创作的特性,部分颜色相近区域的成分含量基本一致,仅有少部分区域出现较大波动,因此特定区域的成分可作为该区域的独有的指纹信息作为其鉴定的一个依据。     

文物红色系颜料高光谱识别指数研究

红色系矿物颜料曾被艺术家们大量地使用在古画和古建筑上.正确地识别出不同种类的红色系颜料对于文物监测与修复具有重要意义.传统的颜料识别主要依靠化学分析,不仅识别速度慢、识别范围小,而且对文物进行取样操作会造成文物的永久损伤.高光谱技术对颜料进行无损识别可以很好地解决这些问题.选用辰砂、胭脂、银朱、朱膘、朱砂、赭石、赭粉、...     

Investigation of ferrites properties with polyaniline layer in anticorrosive coatings

The presented paper is devoted to pigments of various chemical compositions and particles morphology surface-modified by polyaniline layer as corrosion inhibitors to coatings. They were synthetized of pigments on the spinel base, ferrites with contents of Zn, Mg and Ca cations with isometric and nonisometric forms of primary particles. These pigments were surface-modified with electrically conductive polymer, polyaniline, by the oxidative polymerization of aniline. The surface composition of coated pigments was characterized by Fourier transform infrared (FTIR) spectrum and scanning electron microscopy (SEM). For testing the properties of pigments prepared, the model coatings compositions were formulated using solvent-based alkyd resin. On the tested samples, corrosive tests were performed. The present research has shown that the presence of polyaniline has better efficiency in protection against corrosion than spinel-type pigments alone in the selected alkyd resin.     

Three generations of inorganic phosphates in solvent and water-borne paints: A synergism case

This research work is intended to compare the anti-corrosive properties of three generations of inorganic phosphate pigments in solvent-based paints and in water-borne ones, both of the epoxy type. The anti-corrosive properties of phosphate pigments were assessed by means of electrochemical techniques (corrosion potential measurements, polarisation tests, etc.), employing a steel electrode dipped into pigments suspensions. The behaviour of these pigments in anti-corrosive paints, formulated with different binders, have been studied by accelerated (salt spray cabinet and humidity chamber) and electrochemical tests (corrosion potential and ionic resistance measurements).Accelerated and electrochemical tests allowed to differentiate the anti-corrosive performance of the three phosphates studied in this research. These test are also able to detect and characterise possible synergism between the water-borne resin and the pigments.     

Characterization of chromium‐containing ceramic pigments by XRF and XRD

As no methodology was found in the literature for characterizing ceramic pigments chemically and mineralogically, the present study was undertaken to establish a methodology for the chemical and phase characterization of ceramic pigments by x‐ray fluorescence (XRF) spectrometry and x‐ray diffraction (XRD). In view of the large number of pigments described in the literature (around 44), the present study was limited to characterizing pigments that contained chromium, which is the most versatile chromophore used in ceramics. Copyright © 2004 John Wiley & Sons, Ltd.     

受干扰光谱信息中矿物颜料粒径信息的获取

矿物颜料的准确配色是实现文物壁画高品质修复,颜色高保真还原的关键技术。矿物颜料颗粒的粒径大小是影响矿物颜料颜色信息和光谱反射率信息的一个重要因素。准确获取壁画表面的矿物颜料光谱反射率信息,是实现颜料颗粒粒径信息识别的有效途径。但是,由于壁画表面矿物颜料部分采样点的光谱信息受到了干扰,无法与不同粒径的矿物颜料的光谱数据库准确匹配,因此也无法从采集的光谱信息中获取有效的粒径信息。针对受干扰的颜料光谱信息,提出利用比值导数法对其进行处理。把光谱信息从光谱反射率空间转换到比值导数光谱空间进行匹配,降低光谱中的干扰信息,增强矿物颜料颗粒本身的光谱特征信息。以壁画中常用的不同粒径的石青和石绿矿物颜料为实验对象,制成色块样本,以基底和白色颜料为主要影响因素,对文中提出的方法进行测试。光谱角度量的结果和光谱曲线图的匹配结果显示,在比值导数光谱空间,获得了满意的光谱匹配精度。验证了文中提出的分析方法可以解决实验中受干扰颜料光谱匹配不准确而无法获得粒径信息的问题,能够为壁画修复过程中矿物颜料的配色提供准确的粒径信息参考。     

中国古画矿物颜料光谱混合模型初探-以石青和石绿为例

高光谱遥感技术对文物完全无损,适于对中国古画等文物进行颜料的鉴别与分析,但是中国古画中混合颜料不同成分的定量分析仍然是文物颜料分析领域中的难点。针对中国古画中经常出现的混合颜料现象,以石青、石绿两种典型的矿物颜料为例,选用粒度大小相同的两种矿物颜料粉末,按照不同的体积比例精确配比获取颜料样本,然后精确控制实验条件获取其光谱。对混合光谱分别用全约束最小二乘法进行全波段光谱解混,用比值导数解混算法进行单波段光谱解混,然后评定解混精度并对解混结果进行对比分析,探讨这两种矿物颜料的光谱混合模型。实验结果表明,石青、石绿两种矿物颜料的光谱混合从总体上来说非线性混合特征较强,但是在局部某些波段又基本符合线性混合模型,利用这些波段采用比值导数法解混,可以得到远高于全波段解混精度的定量分析结果。     

Pump-probe imaging of historical pigments used in paintings

A recently developed nonlinear optical pump-probe microscopy technique uses modulation transfer to sensitively extract excited-state dynamics of endogenous biological pigments, such as eumelanin and pheomelanin. In this work, we use this method to image and characterize several inorganic and organic pigments used in historical art. We show substantial differences in the near-IR pump-probe signatures from nominally similar pigments and suggest extensions to art restoration.     

Synthetic organic pigments in contemporary Balinese painting: a Raman microscopy study

The colour palette from two 20th century and one 21st century Indonesian paintings from the island of Bali was determined by Raman microscopy. There is very little information concerning the artistic techniques from this region of the world and the influences in materials introduced by western artists. The most interesting finding of our study was the increasing substitution of natural pigments by modern synthetic organic pigments. The findings were also compared with samples of representative pigments commonly used by Bali artists, donated by a renowned Balinese painter. Raman microscopy, combined with Fourier transform infrared spectroscopy, high‐performance liquid chromatography and μ‐EDXRF, was able to separate the different components on several colours, and to identify both synthetic organic pigments and inorganic components. Three azo pigments from the diarylide subclass, PY 83, PY 55 and PO 16, were identified on the yellow, brown, red and orange colours. A copper phthalocyanine blue PB 15:x and a basic dye BB 26 were responsible for the blue colours, the former admixed with ultramarine blue. Goethite was sometimes introduced to create the green colour. Two other basic dyes, BY2 and PG 4, were the main chromophores of the yellow and green samples of local pigments. The inorganic pigments comprised bone white, bone black, carbon‐based black pigment, haematite, goethite, vermilion, ultramarine blue and anatase. Finally, the ground layer of all the paintings was identified as rice starch, with a double function of a white pigment. Copyright © 2012 John Wiley & Sons, Ltd.     

中国古代艺术品常用矿物颜料的拉曼光谱(二)

在本刊前一篇文章中,我们讨论了拉曼光谱在艺术品分析和考古学应用方面的实验技术并报道了一些中国古代艺术品中经常使用的红色、黄色和白色矿物颜料的拉曼光谱。本文延续前文工作,测量了一些中国古代艺术品中常用的蓝色、绿色和黑色矿物颜料的拉曼光谱,介绍了相关的背景知识,并对这些光谱进行了解析,我们相信,一套比较全面的颜料拉曼光谱数据,对于拉曼光谱技术在考古学和艺术品分析方面的应用将会起到重要的参考价值。     

A multi-analytical approach for the study of the pigments used in the wall paintings from a building complex on the Caelian Hill (Rome)

In the present study, shards from Roman wall paintings (from the end of the first century to the fourth century A.D.) decorating the domus below the Basilica of SS. John and Paul on the Caelian Hill (Rome), were analyzed in order to identify the pigments used. The analytical techniques employed for the characterization of the pigments were the scanning electron microscope coupled with an energy dispersive spectrometer (SEM-EDS) and infrared spectroscopy (ATR and micro ATR). While SEM-EDS allowed to perform a qualitative analysis of the material, by FT-IR chemical species have been identified. The pigments identified were those mentioned in the literature for the Imperial Roman fresco painting: different types of ochre (yellow and red), mixtures containing lead, green earths and precious pigments such as cinnabar and Egyptian blue. They were often used as mixtures and the use of the most valuable pigments (cinnabar and Egyptian blue) were found in the most ancient rooms.     

1945年银行票据样品印刷颜料无损鉴定

利用超景深三维视频显微镜、激光显微共聚焦拉曼光谱仪、扫描电镜-能谱仪等,对一张1945年银行票据样品的印刷颜料进行测试分析,结果显示该票据印刷使用了颜料红146和颜料红53∶1等有机颜料,以及朱砂、碳黑、普鲁士蓝、副雄黄和χ构型雄黄等无机颜料,并推测棕黑色手写字迹由蓝黑墨水老化褪色形成。票据中各处色块多为单一呈色,有两处印章由朱砂与不同晶型的雄黄共同呈色,并且首次发现χ构型雄黄和副雄黄作为印刷颜料使用。研究表明,上述三项技术的联用可以成功地对纸质品上的有机及无机颜料进行无损鉴定,在纸质文物研究中具有广阔的应用前景。