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。     

Raman spectroscopy in the diagnosis of the wall painting History of Concepción,Chile

Pigments and fresco‐related materials from the wall painting Historia de Concepción by Gregorio De La Fuente in Concepción, Chile were identified by Raman microscopy. The pigments were compared with those obtained from the artist's studio, and results allowed inference about subsequent interventions. Materials coming from processes such as salt efflorescence were also studied. The results contribute to the diagnosis of the current conservation state of the wall painting for its future restoration. Copyright © 2011 John Wiley & Sons, Ltd.     

古壁画、陶彩颜料的拉曼光谱分析

本文利用拉曼光谱对河南班村遗址出土的仰韶彩陶陶彩以及河北磁县湾漳东魏北齐大型壁画墓中的壁画颜料进行了分析,成功的测定出陶彩及壁画颜料的成分。这一研究工作表明,拉曼光谱作为现代技术非常适合于易损和不允许取样的珍贵艺术品颜料的无损分析     

故宫奉先殿清初彩画颜料成分分析

故宫奉先殿是明清两代皇帝祭祀祖先的家庙,地位仅次于太庙。奉先殿始建于明成祖时期,现存建筑主要建于康熙时期,其上保留了为数不多的清初彩画,是研究清初彩画的珍贵实物。利用显微观察、扫描电子显微镜能谱和激光拉曼光谱分析,对取自奉先殿的彩画颜料进行分析鉴定。结果表明,奉先殿彩画中部分红色和蓝色颜料层存在分层现象,表层颜色鲜艳明亮,中层和下层颜色偏浅,每层所用颜料配方不同。红色颜料有朱砂、铅丹和铁红,绿色颜料均为氯铜矿,蓝色颜料均为石青,用铅白打底。浅色颜料由主显色矿物颜料加入以铅白为主的白色颜料混合调制而成。其中浅红色由铅丹与铅白调和而成,浅绿色由氯铜矿与铅白调和而成。浅蓝色颜料中未发现铅白,但含有大量Al元素和Si元素,推测含有高岭土。浅蓝色颜料有可能是由石青与高岭土调制而成。奉先殿彩画中未发现清晚彩画常用的合成群青、巴黎绿等颜料,反映出奉先殿彩画的绘制年代很有可能就是档案记载的康熙年间,之后未有大修。高岭土作为白色颜料调配浅色颜料在彩画制作中比较少见,奉先殿彩画中高岭土的发现丰富了清代早期彩画颜料制作的资料,具有一定的学术意义。     

Raman and Infrared Spectroscopic Characterization of the Silicate Mineral Lamprophyllite

The mineral lamprophyllite is fundamentally a silicate based upon tetrahedral siloxane units with extensive substitution in the formula. Lamprophyllite is a complex group of sorosilicates with general chemical formula given as A₂B₄C₂Si₂O₇(X)₄, where the site A can be occupied by strontium, barium, sodium, and potassium; the B site is occupied by sodium, titanium, iron, manganese, magnesium, and calcium. The site C is mainly occupied by titanium or ferric iron and X includes the anions fluoride, hydroxyl, and oxide. Chemical composition shows a homogeneous phase, composed of Si, Na, Ti, and Fe. This complexity of formula is reflected in the complexity of both the Raman and infrared spectra. The Raman spectrum is characterized by intense bands at 918 and 940 cm^?1. Other intense Raman bands are found at 576, 671, and 707 cm^?1. These bands are assigned to the stretching and bending modes of the tetrahedral siloxane units.     

显微拉曼光谱在宝石鉴定中的应用

探讨了用显微共焦拉曼光谱仪鉴定宝石的可行性、可靠性。结果表明,根据对宝石本体的拉曼测量很容易识别真假宝石。而用显微共焦系统对微小包裹的测量可提供宝石是天然或人造的信息,甚至可追踪天然宝石的产地。我们还注意到,与拉曼谱同时记录到的光荧光谱也是有关样品的珍贵信息,有时也可据此判明宝石是天然的还是人工合成的     

红外和拉曼光谱的煤灰矿物组成研究

研究煤灰中矿物质的性质通常从矿物组成的表征入手。为了分析两种高硅铝煤灰的矿物成分,采用傅里叶变换红外光谱(FTIR)、拉曼光谱和X射线衍射(XRD)技术对煤灰样进行了测试和综合表征,将FTIR和拉曼光谱的分析结果与XRD进行了比较。FTIR结果表明,在1 100~1 000 cm-1范围内高硅铝煤灰出现最强的特征峰,例如石英峰(1 089 cm-1)和偏高岭石峰(1 042 cm-1),它们都归属于Si-O伸缩振动。对原始红外谱图进行二阶导数处理后,可获得重叠峰的峰位,有助于更完整的解析矿物吸收峰,从而获得更丰富的矿物组成信息。煤灰中硬石膏的红外和拉曼光谱发现,在1 157,1 126和674 cm-1的拉曼光谱峰与在1 151,1 120和678 cm-1的红外光谱峰振动模式分别相同且峰位接近,还存在一些完全不同的拉曼光谱与红外光谱峰,表明这两种光谱存在互补性。尽管煤灰中锐钛矿含量很低,但由于Ti-O的极化率很高,因此拉曼光谱显示锐钛矿的144 cm-1峰远远强于石英的461 cm-1峰。XRD结果表明,煤灰中主要存在石英、云母、赤铁矿、硬石膏和未知的无定形相矿物,FTIR和拉曼光谱综合分析的结果表明除了这些矿物,还存在偏高岭石、无定形氧化硅、长石、方解石和锐钛矿等。在定性分析方面,将FTIR和拉曼光谱结合起来比XRD单独获得的矿物组成信息更为详细。     

Characterization of diamond-like carbon films by SEM, XRD and Raman spectroscopy

Diamond-like carbon films were deposited by electrolysis of a water-ethanol solution on Cu at low voltages (60-100 V) at 2 mm interelectrode separation. The films were characterized by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and Raman spectroscopy. The films were found to be continuous and compact with uniform grain distribution. Raman spectroscopy analysis revealed two broad bands at ∼1350 and ∼1580 cm⁻¹. The downshift of the G band of graphite is indicative of the presence of DLC. For XRD analysis, the three strong peaks located at 2θ values of 43.2°, 74.06° and 89.9° can be identified with reflections form (1 1 1), (2 2 0) and (3 1 1) plane of diamond.     

青海热贡地区传统建筑彩画颜料光谱特征分析研究

青海省热贡地区是安多藏区藏式建筑彩画艺术的重要产地,作为热贡艺术的重要组成部分影响甚广。热贡地方建筑彩画不仅是附着建筑栋梁之上的艺术瑰宝,更是一项延续至今的传统技艺,至今仍有大批传统匠人画师从事相关行业。热贡地方建筑彩画有独立的用色方法和颜料制作工艺,对其所用传统颜料进行科学检测是系统研究该地区建筑彩画的基础性工作,在进一步研究热贡地区建筑彩画的制作工艺和艺术特色,传承地方建筑彩画技艺和完善保护政策等方面具有积极意义。通过对同仁市隆务寺夏日仓行宫火供殿所用当地传统建筑彩画颜料的采样,运用X射线荧光光谱、X射线衍射分析、激光显微拉曼光谱分析等多种实验分析方法,对颜料样品进行分析,测定其主要显色物质和成分占比。结果表明,热贡地方建筑彩画所用颜料多为无机颜料;蓝色颜料主要是人造群青;绿色颜料的主要矿物组成为绿土,显色物质为蒙脱石,存在将植物色染料加入当地所产的富镁蒙脱石中混合使用的可能性;红色颜料的主要矿物组成为铁红（赭石类红土）,通过焙烧富铁矿土来人工合成,材料来自于当地吾屯村所产红色赭石类粘土;黄色颜料主要矿物组成为密陀僧、硫磺及其他植物色染料制备而成;黑色颜料为碳黑,符合木炭黑的性状特征;白色颜料主要为生石灰及氧化镁粉,并在其他颜料中广泛使用石灰及氧化镁粉作为调色颜料;推测部分样品中含有包金土及植物色素染料、其他人工合成颜料的可能性。整体来看,热贡地区建筑彩画所用颜料成本价格较低,制取难度不大,来源大多是当地常见的矿土料和动植物染料,传统的制料工艺较简单,颜料多呈现为组分复杂的混合物状态;密陀僧、包金土和群青等颜料多来自于内地及国外,颜料人工合成的历史较早,反映出热贡地区建筑彩画在颜料使用上不仅使用本土材料制备,也广泛使用外来颜料的历史传统,为进一步研究热贡地区建筑彩画领域内汉、藏等多民族文化交往、交流、交融历史提供了良好实证材料。     

拉曼光谱结合LSTM长短期记忆网络的樱桃产地鉴别研究

现在樱桃市场上存在着大量以次充好的不良现象,严重损害了名牌樱桃的品牌经济效益,所以亟需一种能对不同产地樱桃实现快速无损鉴别的技术.拉曼光谱溯源技术作为光谱溯源技术的一种,由于具有快速、高效、无污染、无损分析等优点,逐渐得到相关研究者的重视.长短期记忆(LSTM)网络是一种具有记忆性的反馈神经网络,它是循环神经网络的一种...     

Teaching Raman Spectroscopy in Both the Undergraduate Classroom and the Laboratory with a Portable Raman Instrument

We have evaluated a small portable Raman instrument on loan from B&W Tek, Inc., and have determined that it can successfully be used in the classroom both as a visual aid for teaching the fundamentals of Raman spectroscopy and for a variety of undergraduate experiments as a normal component of an instrumental analysis class. Having portable Raman instrumentation would allow the instructor to demonstrate the principles of Raman spectroscopy, as well as the concepts of calibration curves, blank subtraction, detection limits, and regression analysis. Both qualitative and quantitative types of experiments were done for solid Tylenol tablets, aqueous solutions of isopropyl alcohol, dimethyl sulfoxide, methanol, and ethanol, and gaseous CO₂ and N₂O₄. Additionally, surface‐enhanced resonance Raman spectra of Rhodamine 6G were obtained using a chloride ion–activated silver colloid. Spectra from the B&W Tek, Inc., instrument were comparable to literature Raman spectra.     

Understanding tip‐enhanced Raman spectra of biological molecules: a combined Raman,SERS and TERS study

Although conventional Raman, surface‐enhanced Raman (SERS) and tip‐enhanced Raman spectroscopy (TERS) have been known for a long time, a direct, thorough comparison of these three methods has never been carried out. In this paper, spectra that were obtained by conventional Raman, SERS (on gold and silver substrates) and TERS (in ‘gap mode’ with silver tips and gold substrates) are compared to learn from their differences and similarities. Because the investigation of biological samples by TERS has recently become a hot topic, this work focuses on biologically relevant substances. Starting from the TER spectra of bovine serum albumin as an example for a protein, the dipeptides Phe–Phe and Tyr–Tyr and the tripeptide Tyr–Tyr–Tyr were investigated. The major findings were as follows. (1) We show that the widely used assumption that spectral bands do not shift when comparing SER, TER and conventional Raman spectra (except due to binding to the metal surface in SERS or TERS) is valid. However, band intensity ratios can differ significantly between these three methods. (2) Marker bands can be assigned, which should allow one to identify and localize proteins in complex biological environments in future investigations. From our results, general guidelines for the interpretation of TER spectra are proposed. Copyright © 2012 John Wiley & Sons, Ltd.     

Identification of individual isotopes in a polymer blend using tip enhanced Raman spectroscopy

For the first time, tip enhanced Raman spectroscopy (TERS) blinking measurements are used to identify the individual isotopes of non‐Raman resonant polystyrene in a miscible, binary blend. This demonstrates the sensitivity and selectivity required for nanoscale chemical imaging and broadens the types of surface components potentially identifiable with TERS. Copyright © 2015 John Wiley & Sons, Ltd.     

Pigment identification and decoration analysis of a 5th century Chinese lacquer painting screen: a micro‐Raman and FTIR study

To investigate the pigments and decoration applied to a wood‐based lacquer painting screen from the tomb of Si‐ma Jin‐long, Shanxi Province, central China, made by Chinese craftsmen in the 5th century, a combination of micro‐Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), wavelength dispersive X‐ray fluorescence (WDXRF), and microscopic examination was used. The obtained results are as follows: (1) the black, yellow, and red colors are identified as carbon black, orpiment and realgar, and cinnabar, respectively, by using micro‐Raman spectroscopy. The FTIR result shows that the white pigment filled in the leaves is not lead white, as assumed in the literature, but gypsum. Whether lead white was used at other locations remains unanswered and requires more samples for further work; (2) the thickness of each discernable pigment layer, as observed under the microscope, is approximately equal and the differences among them are small, suggesting a superfine painting skill; besides, a noticeable smooth interface between wood and the red grounding substance indicates that a polishing process might have been applied before the painting; (3) the red background was proved to contain cinnabar, but further FTIR analyses found no evidence for the presence of Chinese wood oil; and (4) the most interesting finding, rarely reported before, is that white grains of different sizes are found in both pigment layers and the grounding substance, which are perhaps an intentional addition. Further, in situ XRF and Raman analyses indicate that they are sourced from hydroxyapatite, coming probably from the intentional addition of animal bone ash to the lacquer. But how such a process could be finished and what purpose it served have not yet been answered. Copyright © 2009 John Wiley & Sons, Ltd.     

Micro‐Raman and infrared analysis of medieval pottery findings from Braničevo,Serbia

A selection of Byzantine table pottery (17 samples) dating from the period between the beginning of the 12th century and the first half of the 13th century, discovered at Braničevo in Serbia, were analysed by Fourier transform infrared, micro‐Raman and scanning electron microscopy with energy dispersive spectroscopy and petrography analysis. The aim of the investigation was to determine the chemical and mineralogical composition of the body and of the glaze and thus to determine the production technology. Fourier transform infrared spectroscopy provided data for estimating the firing temperature and the basic mineralogical composition, and micro‐Raman spectroscopy was applied to study and characterise both the glaze and the body of the analysed sherds. It was found that noncalcareous clays, characterised by a rich mineral assemblage, were fired at temperatures between 700 and 900 °C. Oxidizing atmosphere was applied in the production of the red colour pottery. The dark and grey coloured paste of one group of sherds was produced by firing organic matter‐rich clays in a reducing environment. The main type of transparent glaze was identified as lead‐rich, and two samples were alkali–lime glazed. Copyright © 2011 John Wiley & Sons, Ltd.     

不同堆砌层数煤系石墨的拉曼光谱表征及其表面石墨化均匀程度

采用多激发波长(325, 405, 514, 633和785 nm)以及显微拉曼面扫描技术对不同芳香层片平均堆砌层数的煤系石墨及其表面石墨化均匀程度进行表征。结果表明：对无序石墨,石墨微晶的尺寸较小并任意取向,随着平均堆砌度及堆砌层数增加,石墨微晶边缘的拉曼光谱特征显现。在无序结构向有序转化的同时,石墨微晶缺陷逐渐消亡,拉曼光谱一级模中D3、 D4峰逐渐不显著或消失,但是其倍频峰均微弱出现,尤其2D1峰强度逐渐增大。将I_D1/I_D2参数的含义进一步引申为缺陷类型及平均定向性,且无烟煤的I_D1/I_D2极大,随着石墨微晶尺寸增大(d₀₀₂<0.344 0 nm),至三维有序结构的石墨时I_D1/I_D2最小。在不同激发波长下G峰半高宽总是随着无序度的减小而减小,D1峰和2D1峰等均显示较强的色散效应,各峰强度随激发光能量的增大而增大,在紫外激发下,D1和G峰峰位差显著小于可见光激发。随激发波长的增加,D1峰向着低波数方向移动,2D1峰色...     

Correlation of monomer structures of tripalmitin with the spectroscopic fingerprint of polymorphs: infrared,Raman, and DFT study

In the light of application of vibrational spectroscopy in medical diagnosis, it is necessary to have a tool to distinguish between different lipids that may be present in biochemical samples such as cells and tissues. One of the most common lipids in the human body are triglycerides. Therefore, the aim of this work was to investigate the model triglyceride, namely tripalmitin in order to find the differences between the vibrational signatures of its polymorphs and interpret them with the help of quantum‐chemical computations. Although monomeric models are not sufficient to reproduce polymorphs structure, analysis of these models is very helpful in understanding of relations between the structure and changes in vibrational spectra. Copyright © 2012 John Wiley & Sons, Ltd.     

Using Raman spectroscopy as a tool for the detection of iron in glass

Raman spectroscopy has been used to identify iron‐containing glasses. This nondestructive technique offers a fast method to obtain qualitative information about the presence of iron oxides in glass. The effect of the iron content in glass samples is reflected on the topology of the Raman spectra: A strong link between the ratio of the Q₂/Q₃ vibration units of the silica tetrahedral structure is seen. If matrix effects are taken into account, also (semi)quantitative results can be obtained from the calibration lines. The linear calibration is based on the normalized band intensity at 980 cm⁻¹ (I₉₈₀/I₁₀₉₀) and the iron oxide concentration for similar glasses. In amber and dark colored glasses, an extra peak in the spectrum indicates the presence of a FeS chromophore. Different series of glasses of various origins (ancient and modern/industrial glass) have been considered. Copyright © 2011 John Wiley & Sons, Ltd.