A post-Byzantine icon of St Nicholas painted on a leather support. Microanalysis and characterisation of technique

The pigments, organic materials and techniques used on a post-Byzantine icon of St Nicholas were determined by means of several micro-analytical techniques. The icon painter covered the leather support with silver leaf about 3 μm thick to create a smooth working surface. Animal glue was used to secure the leaf to the leather, and FTIR spectroscopy has identified another layer, 30–60 μm thick, of the same material applied as a primer above the silver. Above that, a layer of lead white covering the entire surface creates a white substratum serving the same purpose as the gesso on a wood panel. The colour palette, determined by means of scanning electron microscopy and FTIR spectroscopy, is very simple. Only seven colours were identified: lead white, caput mortuum, red and yellow ochre, cinnabar, carbon black and smalt. As far as we know, this is the first time that smalt has been found on a Byzantine icon. Since smalt was chemically synthesised only after 1500 AD, it may be concluded that this icon was painted after the end of the 15th century. Beeswax was used as a protective varnish.     

Material characterization and preservation guidance for a collection of prosthetic limbs developed since 1960

National Museums Scotland has collections relating to many areas of science and technology, including medical science. This paper considers technical and conservation issues of an important collection of more than 150 prosthetic limbs. Much of the collection is of prosthetics developed for children born lacking or with malformed upper limbs caused by the prenatal morning sickness drug Thalidomide. However, many other examples are represented and the collection showcases a timeline of bioengineering development covering the past five decades. A wide range of plastics and metals were observed within the pieces examined, with many visibly degraded and degrading. The identification and characterization of these materials and their condition are fundamental to interpreting the development of the collection, for deciding on treatment, and for setting a strategy for future preservation. In addition to visual inspection, three analytical techniques were used to examine the various parts of the selected examples: Fourier transform infrared spectroscopy for polymer identification and condition; X-ray fluorescence spectroscopy to identify the metals and alloys present, and X-radiography to reveal the internal mechanisms of the limbs. Interpretation of the results was greatly enhanced by documentation and conversation with engineers and scientists involved in research and development of the limbs. The combination of different materials, some with conflicting environmental requirements, makes storage and display challenging as the goal is to prevent degradation of any part the object. Some objects were found to be actively degrading and for these separate storage solutions have been recommended to slow the emission of volatile degradation products that would cause further damage throughout the collection.     

Removal and transformation of dissolved organic matter in secondary effluent during granular activated carbon treatment

This paper focused on the removal and transformation of the dissolved organic matter （DOM） in secondary effluent during the granular activated carbon （GAC） treatment. Using XAD-8/XAD-4 resins, DOM was fractionated into five classes： hydrophobic acid （HPO-A）, hydrophobic neutral （HPO-N）, transphilic acid （TPI-A）, transphilic neutral （TPI-N） and hydrophilic fraction （HPI）. Subsequently, the water quality parameters of dissolved organic carbon （DOC）, absorbance of ultraviolet light at 254 nm （UV-254）, specific ultraviolet light absorbance （SUVA） and trihalomethane formation potential （THMFP） were analyzed for the unfractionated and fractionated water samples. The results showed that the order of the DOC removal with respect to DOM fractions was observed to be HPI〉HPO-A〉HPO-N〉TPI-A〉TPI-N. During the GAC treatment, the THMFP of the unfractionated water samples decreased from 397.4 μg/L to 176.5 μg/L, resulting in a removal efficiency of 55.6%. The removal order of the trilaalomethanes （THMs） precursor was as follows： HPO-A〉TPI-A〉TPI-N〉HPO-N〉HPI. By the GAC treatment, the specific THMFP of HPO-A, TPI-A, TPI-N and the original unfractionated water samples had a noticeable decrease, while that of HPO-N and HPI showed a converse trend. The Fourier transform infrared （FTIR） results showed that the hydroxide groups, carboxylic acids, aliphatic C-H were significantly reduced by GAC treatment.     

温度和时间对杉木苯酚液化残渣成分变异的影响

该研究采用FTIR仪器分析,进一步研究不同温度、不同时间的液化工艺条件下,杉木液化残渣中的化学组分官能团变化以及相应的变化规律.     

同株夹竹桃双色花红外光谱分析研究

首次利用傅里叶红外光谱仪测定了同株夹竹桃双色花的红外光谱图,分析比较了双颜色的花在红外光谱上的差异程度。结果表明,由于不同颜色的花所含的化学成分和相对含量的差异,其红外光谱吸收峰的位置和强度均有不同。通过对红外光谱图的主要特征峰的峰位、峰强的分析,推断出它们可能含有甙类等物质。此结果,为今后对夹竹桃的进一步开发利用提供了依据。     

航天诱变番茄种子遗传变异的FTIR分析

本文利用傅里叶红外变换光谱,跟踪分析了航天育种M9代大、小番茄种子品系的变异,并对比分析了M9代与M7代大、小番茄种子品系较对照种子品系红外特征谱的变异.结果显示,航天环境对M9代番茄种子所产生的可遗传变异的光谱特征,主要发生在1160～1100cm-1范围内,M9代的谱图在该区域的特征谱面积较对照种子品系的仍保持显著增大,与M7代所产生的变异完全相同.M9代番茄种子品系在1160～1100cm-1范围内特征谱面积增大,表示M9代番茄种子的C-O伸缩振动仍保持显著增强.M9代番茄种子品系这一稳定的航天光谱变化特征,与航天番茄果实中的维生素C和可溶性糖的显著增大是紧密相关的.因而,M9代的特征光谱在1160～1100 cm-1范围内的变异,属于可遗传性变异,也即航天番茄的维生素C和可溶性糖显著增加的生物变异,属于可遗传性变异.利用FTIR法研究航天条件对农作物种子产生的可遗传性变异,是一种快速、可靠和有效的方法.     

牛血清白蛋白二级结构构象的红外光谱研究

研究了BSA(bovine serum albumin,牛血清白蛋白)及其水溶液的红外光谱,通过傅里叶自转积谱分析,对上述红外光谱的二级结构构象进行了指认.结果表明,BSA处于水溶液状态与固态时的二级结构是不同的.随着溶液浓度的降低(3.241×10-1～4.032×10-2g·ml-1),酰胺Ⅰ带二级结构子峰存在明显的位移现象,即1609.86 cm-1位移到1608.24cm-1,1633.85位移到1638.36 cm-1,1653.69 cm-1位移到1656.10 cm-1,1681.16 cm-1位移到1674.87 cm-1,1694.88 cm-1位移到1690.78 cm-1,而1621.50 cm-1附近的子峰位移现象不明显.     

A study of stearyl alcohol bloom on Dan Hill PVC dolls and the influence of temperature

A study was conducted to investigate white bloom found on more than 130 polyvinyl chloride (PVC) dolls from the 1980s and 1990s produced by the Danish factory Dan Hill Plast A/S. The bloom was discovered on the dolls after 10 years of storage in a climate controlled facility with average temperature at 11–12°C and a relative humidity at 50?±?5%. Analysis of the dolls and the bloom was carried out using Fourier transform infrared spectroscopy, which revealed that the bloom consisted primarily of stearyl alcohol. Subsequent analysis with gas chromatography–mass spectrometry showed a minor presence of cetyl alcohol. It is proposed that the alcohol had been added as a lubricant to aid flow during processing. The stearyl alcohol was almost completely reabsorbed into the PVC dolls following one month storage at room temperature, suggesting that low temperature storage played a decisive role in the appearance of the bloom. It is likely that a decrease in temperature has led to a decrease in compatibility of the stearyl alcohol in the PVC compound, thus promoting its exudation. This paper also discusses an extreme bloom of white crystals on other PVC dolls of unknown provenance.     

FTIR法测定隧道内不明气体

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.