Physical and mechanical properties of waterlogged wood treated with hydrolyzed feather keratin

The physical and mechanical properties of waterlogged wood treated using avian feather were investigated. Avian feather is mainly composed of keratin protein and expectable materials for industrial utilization. The feather hydrolysate enhanced the mechanical properties of waterlogged wood and recovered the correlations between modulus of rupture (MOR) and modulus of elasticity (MOE) and anisotropy. The color of the wood treated with hydrolyzed feather solution exhibited natural wood texture. The feather hydrolysate had antimicrobial activity. However, the wood treated with hydrolyzed feather solution showed high hygroscopicity.     

Swift Creek at a human scale

ABSTRACT

The interpretive potential of Swift Creek pottery, widely produced throughout Georgia, eastern Alabama, and northern Florida during the Middle and Late Woodland periods between ca. cal AD 100 and 800, has been apparent for many years. Much research has been focused on identifying paddle designs from the impressions left on sherds. Less attention has been devoted to the carving of the wooden paddles and its social context. Drawing inferences from our work on Swift Creek pottery in southern Georgia and Florida, and drawing inspiration from the career of Mark Williams, we consider Swift Creek paddle production “at a human scale.” Extrapolating from the number of paddle designs identified in our sample, we argue that paddle manufacture was an infrequent occurrence, probably conducted by specialists and intended to commemorate major life events.     

Degradation of Archaeological Remains by Shipworm

The marine borer, known as shipworm, has long been known for their degradation of wooden constructions in the marine environment. This review presents the results from a variety of experiments conducted at the National Museum of Denmark throughout the past five years dealing with the in situ preservation of maritime archaeological artefacts in light of the threat from shipworm. The aim of the research has been to improve methods and analyses for conducting experiments with shipworm, and to better our understanding of their attack pattern and how to stop an active attack in situ.     

The Yenikapı Byzantine‐Era Shipwrecks,Istanbul, Turkey: a preliminary report and inventory of the 27 wrecks studied by Istanbul University

Salvage excavations conducted in the Yenikap? quarter of the historic peninsula of Istanbul by the Istanbul Archaeological Museums 2004–2013 have brought to light the Theodosian Harbour on the Sea of Marmara. In addition to thousands of archaeological artefacts, a total of 37 shipwrecks dating from the 5th to the 11th centuries AD were uncovered, constituting the biggest collection of medieval ships uncovered at a single excavation site. The present article deals with 27 wrecks in the charge of the team from Istanbul University's Department of Conservation of Marine Archaeological Objects, consisting of 23 merchantmen and four galleys. The wrecks are presented with their general characteristics. The preliminary evidence from the Yenikap? wrecks regarding the development from shell‐based to skeleton‐based philosophy is discussed, and various building phases presented.     

‘Land of Fires’: Urban Growth,Economic Crisis,and Forest Fires in Attica,Greece

This study investigates the spatial distribution and basic characteristics of 2692 forest fires between 2000 and 2011 in Attica, Greece, a rapidly expanding urban region. Fire variables were assessed, together with variables describing the socio‐economic local context in three distinct periods of Athens’ expansion (2000–2003: semi‐compact expansion and economic growth before the 2004 Olympic Games; 2004–2007: infrastructure development and discontinuous expansion following the Olympic Games; 2008–2011: crisis‐driven decline of the construction industry). Fire characteristics changed over the three periods following the negative trends in the construction industry. Burnt areas decreased in the rural area around Athens and the opposite pattern was observed in the peri‐urban belt. Our findings suggest that the temporal and spatial distribution of forest fires in Attica reflects the construction boom stimulated by the 2004 Olympic Games and the subsequent economic crisis.     

Evaluation of the rate of wood degradation at the Iron Age archaeological site of Biskupin,Poland

A study was made of the degradation of archaeological Scots pine (Pinus sylvestris L.) at the Iron Age archaeological site of Biskupin, Poland. Wood degradation was evaluated after 10 years of deposition of samples in different burial conditions (mineral soil, peat and water) and at different depths (25, 50 and 100 cm) at the location of the original archaeological wood from the Lusatian culture settlement. Changes in the wood samples were assessed on the basis of selected physical (maximum water content, basic density and porosity) and chemical (chemical composition, structure of cellulose and lignin) properties. The observed degradative changes were different for samples deposited in different locations of the archaeological site and at different depths. They relate mainly to carbohydrates—both cellulose and hemicelluloses—although the structure of lignin also underwent changes. The experiment using wood that had been degraded to a similar degree to the Biskupin wood enabled identification of the actual danger of degradation of the latter. It was found that the remains of the wooden structure of the Biskupin settlement are degrading, despite the favourable physicochemical conditions prevailing at the site, and it is necessary to take measures to prevent its further decomposition.     

古旧木材保存状况多参数检测研究进展

作为人类文化遗产的重要组成部分,古旧木材保存状态的评价及保护至关重要。为了推进对古木材保存评价的深入研究,通过对多参数检测(微形态学、物理学、化学)在微观尺度下评价古旧木材保存状况及腐蚀机理的研究成果进行了综述,在介绍了从木材细胞形态、物理孔隙结构、化学组分含量、分子结构、分子量分布等方面对古旧木材进行评价的基础上,较为全面地阐述了检测各参数的不同表征方法,包括扫描电镜法、氮气吸附法、高效液相色谱法、气相色谱/质谱联用法等,具体分析了不同表征方法间的优缺点,说明了多参数检测古旧木材保存状况的可行性及重要性,并希望以此为切入点探讨古旧木材的宏观力学性能。研究结果在木质文化遗产和历史木构建筑的保护方面具有极大价值。     

Study of interactions between polyethylene glycol and archaeological wood components by C high-resolution solid-state CP-MAS NMR

While use of polyethylene glycols, PEG, polymers for archaeological wood conservation has been well established, there is almost no study of such composite materials with carbon thirteen high-resolution solid-sate NMR. We demonstrate that NMR is an useful analytical tool to characterize rapidly samples of conserved wooden objects. By choosing an appropriate value of the contact time (from 3 to 5 ms) for which the PEG component gives only a small residual NMR signal in the CP-MAS experiment, it is possible to edit selectively the spectra of the wood components. It allows one to visualize the degradation extent of the archaeological wood even when the conservation processes have been already applied. Moreover, by studying the kinetics of CP-MAS experiments, the time constants, T_1ρH and T_CH values for PEG moiety were computed. From these data, it is shown that either in the crude commercial product or in incorporated in archaeological woods, two components are present and they are the signatures of crystalline (or ordered) and amorphous (or disordered) molecular domains. Moreover, it was shown in the archaeological woods that almost 30% of PEG was in close molecular interactions with lignins. This study is the first evidence that the PEG in conserved wood can interact at a molecular level with wood components. It also demonstrates that the PEG diffuses inside the residual cell walls of archaeological wood. This data are important for scientists in charge of process development for the conservation of wooden artifacts.     

跨湖桥遗址考古木材的二次保护

跨湖桥遗址考古木材出土后经过脱盐处理,然后采用聚乙二醇(PEG)进行定形加固。保护后的考古木材存在色泽变深的问题,需要对这些考古木材进行二次保护。在二次保护过程中,选用1,2-二甲基-3-羟基-4(1H)-吡啶酮复配溶液作为脱盐脱色络合溶液,以PEG为定形加固剂,采用真空冷冻方式进行脱水干燥。二次保护取得了良好的效果,考古木材尺寸和形状基本保持不变,色泽更为自然,木材纹理清晰可见。     

养心殿镇物宝匣中木条的种属鉴定与历史考究

养心殿研究性修缮过程中,位于正脊中央的镇物宝匣向世人展现了明清皇宫建筑中的镇物文化。镇物宝匣是皇宫内建筑的重要组成部分,匣内常放置多种镇物,其中有机质镇物变化较大。养心殿宝匣内装有金钱、元宝、宝石、丝织物及若干木条。其中木条已老化变黑,难以辨识。本研究通过传统微观结构观察法对其种类进行了鉴定。初步判断木条共5类,分别是白木香Aquilaria sinensis(Lour.)Spreng.、檀香Santalum album L.、交趾黄檀Dalbergia cochinchinensis Pierre.、阔叶黄檀Dalbergia latifolia Roxb.、大果紫檀Pterocarpus macrocarpus Kurz.。前两种属于香药,后三种属于红木类木材。三种红木的发现,也为嘉庆年间宫廷内使用此三种红木提供了直接证据。结合文献考证,可能是清宫廷内资源利用及官场的腐败等诸多因素,致使修缮官员以木材边角料代替了部分香药、谷物。养心殿镇物宝匣中木条种类的鉴定对揭示清中期宫廷镇物文化、木材的利用及社会背景具有重要意义。