Rubidium hydroxide polyethylene glycol crown ether in the conservation of old master paintings*

The development of new, gentler methods for the conservation of Old Master paintings, with an emphasis on the removal or thinning of deteriorated varnish, is of high priority. In the course of the deterioration process, oxidative attacks lead to progressive formation of carboxylic acid groups, while many ester bondings are expected to be weakened. A stable RbOH polyethylene glycol complex was a promising tool to react with these moieties and to successfully break down the polymeric varnish layer. The remnants were easily wiped off mechanically. Control studies employing ⁸⁶RbOH and ¹⁴C polyacrylate showed the complete absence of residual cleansing components on the paint surface.     

精确定年的祁连圆柏碳十四年代的加速器质谱测定

前言 1949年,碳十四断代的创始人利比(W.F.Libby)公布了第一批碳十四年代数据,宣告碳十四测年方法取得成功,轰动了整个考古界和地质学界。碳十四     

Translations at the Court of Hákon Hákonarson: a well planned and highly selective programme

This article deals with the translations of Old French works completed at the court of Hákon Hákonarson, king of Norway. The first one was probably completed in 1226 and some 40 followed: translations of epic poems, courtly romances and lais, adventure romances and a fabliau. In all cases, we ought to speak of adaptations and not of word-for-word translations.

Together, these literary works form an outstanding corpus, elaborated mainly for didactical purposes and in order to support Hákon Hákonarson's project to build a monarchy à l'européenne. For that, some literary works were selected and – in their adaptations – some ethical and social values promoted while some others were not; and some great literary works were intentionally ignored and remained untranslated.     

GEOGRAPHICAL PATTERNS IN BIOLOGICALLY AVAILABLE STRONTIUM,CARBON AND OXYGEN ISOTOPE SIGNATURES IN PREHISTORIC SW GERMANY*

In order to interpret strontium and oxygen isotope values in Neolithic human skeletons analysed previously, we begin to map the biologically available strontium, carbon and oxygen isotopic signatures of prehistoric southern Germany by analysing tooth enamel of pigs from archaeological sites distributed around the region. The mapping shows a marked upland–lowland difference in biologically available ⁸⁷ Sr/ ⁸⁶ Sr values, ranging between 0.7086 and 0.7103 in the sedimentary lowlands, and from 0.710 to as high as 0.722 in the crystalline uplands of the Odenwald, the Black Forest and the Bavarian Forest. In addition, carbon isotopes in the carbonate fraction of pig enamel were generally about 1–2 more enriched in ¹³ C in the uplands. Despite the expected depletion of ¹⁸ O with altitude, oxygen isotopes in pig enamel showed little correlation with site altitude, although for pig samples not older than the Iron Age there was some geographical correlation withδ¹⁸O patterns in modern precipitation.     

岩画断代研究——科技考古学领域中一个亟待解决的问题

探索和研究表明,岩画断代问题仍然是困扰岩画研究的难题之一,其主要原因是岩画本身不能够提供可供断代的直接依据。本文综述了目前岩画断代研究中经常使用的自然科学和考古学方法及其存在的问题,提出应用AMS14C是今后研究我国岩绘画断代问题的首选方法,解决岩刻画的断代问题则主要有赖于微腐蚀方法。     

Palaeolithic radiocarbon chronology: quantifying our confidence beyond two half-lives

It is now three decades since Waterbolk introduced evaluation criteria to ¹⁴C chronology. Despite this, and other subsequent attempts to introduce quality control in the use of ¹⁴C data, no systematic procedure has been adopted by the archaeological community. As a result, our databases may be significantly weakened by questionable dates and/or questionable associations between dated samples and the archaeological phenomena they are intended to represent. As the use of chronometric data in general becomes more ambitious, we must pause and assess how reliable these data are. Here, we forward a set of evaluation criteria which take into account archaeological (e.g. associational, stratigraphic) and chronometric (e.g. pre-treatment and measurement) criteria. We intend to use such criteria to evaluate a large ¹⁴C dataset we have assembled to investigate Late Glacial settlement in Europe, the Near East and North Africa, supported by the Leverhulme Trust. We suggest that the procedure presented here may at least form the basis of the development of more rigorous, scientific use of ¹⁴C dates.     

C.S. Lewis: an Irish writer

This article examines the effect of C.S. Lewis's Irish background on his work. It attempts to contradict the assumption that this Belfast-born writer should be included in the English and not the Irish canon. It emphasises that Lewis saw himself as Irish, was seen by others as Irish, and that his Irish background, contrary to what some have written, was important to him throughout his lifetime. It goes on to demonstrate the ways in which his work was influenced by his youth in Ireland and by the Irish mythology that he loved. Furthermore, this article maintains that, as a child of pre-partition Ireland with roots throughout the island, Lewis was influenced by the country as a whole, not just his native Ulster. Finally, it attempts to understand why Lewis, a proud Irishman, did not do more to promote himself as an Irish writer.     

DATING OF THE HOMINID (HOMO NEANDERTHALENSIS) REMAINS ACCUMULATION FROM EL SIDRÓN CAVE (PILOÑA,ASTURIAS, NORTH SPAIN): AN EXAMPLE OF A MULTI‐METHODOLOGICAL APPROACH TO THE DATING OF UPPER PLEISTOCENE SITES

The age of Neanderthal remains and associated sediments from El Sidrón cave has been obtained through different dating methods (¹⁴CAMS, U/TH, OSL, ESR and AAR) and samples (charcoal debris, bone, tooth dentine, stalagmitic flowstone, carbonate‐rich sediments, sedimentary quartz grains, tooth enamel and land snail shells). Detrital Th contamination rendered Th/U dating analyses of flowstone unreliable. Recent ¹⁴C contamination produced spurious age‐values from charcoal samples as well as from inadequately pretreated tooth samples. Most consistent ¹⁴C dates are grouped into two series: one between 35 and 40 ka and the other between 48 and 49 ka. Most ESR and AAR samples yielded concordant ages, ranging between 39 and 45 ka; OSL dating results permitted adequate bracketing of the sedimentary layer that contained the human remains. Our results emphasize the value of multi‐dating approaches for the establishment of reliable chronologies of human remains.     

Subsistence practices and pottery use in Neolithic Jordan: molecular and isotopic evidence

This paper presents direct evidence of subsistence practices and pottery use at a Late Neolithic site at al-Basatîn, northern Jordan. Measurable concentrations of C_16:0 and C_18:0 were recovered from 8 of 10 archaeological pottery fragments through use of a microwave-assisted silica gel and aminopropyl solvent protocol developed for the isolation and concentration of free fatty acids in marine sediments. Subsequent isotopic analysis of the surviving C_16:0 and C_18:0 saturated fatty acids revealed ∂¹³C ratios consistent with those of adipose fats of ruminant and non-ruminant animals pastured on lands adjacent to the Jordan Valley. The high recovery of diagnostic compounds from the al-Basatîn material is discussed in context of a wider examination of the initial development and use of pottery in the Fertile Crescent, and the emerging debate concerning the efficacy of stable carbon isotope values in characterizing organic residues embedded in pottery fragments recovered from the earliest ceramic horizons in the Middle East and Europe.     

放射性碳素测定年代报告(三八)

本报告发表的是中国社会科学院考古研究所考古科技实验研究中心碳十四实验室和中国科学院地球环境研究所西安加速器质谱测试中心在2007～2011年期间测定的40个考古数据。数据表示方式与以往所发报告相同。为方便应用另做如下几点说明。1.碳十四年代半衰期按5568年计算。2.校正年代所用程序为OxCal,校正曲线为1998年公布版本。3.与以往报告相同,所给年代误差范围均为±16,年代范围的概率分布为68.2%。4.由于树轮年代校正曲线各区段形状不同,校正后年代范围可能形成几组,总合概率为68.2%(与过去报告中总合概率表示为100%相同)。5.校正均按单一样品方式处理。6.数据均作碳十三