Miocene wood from the LaTrobe Valley coal measures,Victoria, Australia

An initial study of a collection of fossil conifer wood is reported from the late early Miocene Yallourn Clays, an interseam unit intergrading into the base of the early to middle Miocene Yallourn seam of the LaTrobe Valley, Victoria in southeastern Australia. The fossil wood shares characteristics with the modem genera Dacrycarpus and Dacrydium. On the basis of contiguous, uniseriate tracheid pitting and 1–2 podocarpoid cross field pits, it is placed in the form genus Podocarpoxylon, and the new species P. latrobensis. The wood is compared with extant Podocarpaceae and other Australian fossil woods. Its ring anatomy is consistent with low temperature or rainfall seasonality in the early Miocene.     

古代饱水木材脱水定型机理探讨

从木材干缩的一般理论出发,探讨了古代饱水木材脱水变形的主要影响因素。阐述了古代饱水木材与新鲜木材的区别,提出饱水木材发生形变的主要影响因素同现代木材一样,是由于氢键缔合的结合水挥发,从而引起干缩和开裂。要保持脱水后的定型一方面要加固细胞壁外壁,更重要的从细胞壁内壁进行加固。     

Bio-archaeological evidence of olive tree (Olea europaea L.) irrigation during the Middle Ages in Southern France and North Eastern Spain

Quantitative eco-anatomical analyses were carried out on charred wood from modern olive trees (Olea europaea L.) in order to quantify influence of irrigation on wood characters and to detect irrigated olive specimens among charcoal assemblages dating back to the Middle Ages.     

The Planking Clamp from Tårnby: a Medieval Danish Boatbuilding Tool

At the bottom of a well on a medieval farm on the Danish island of Amager, archaeologists found a planking clamp dated by dendrochronology to 1405 AD. ¹ The clamp is of great importance: very few examples have been found or recognised in Northern Europe to date, and this is the best preserved, and thus provides data about its shape and use; and the size of boat it was used in the construction of. It is discussed whether the clamp was used exclusively for boatbuilding or whether it might also have been used in other crafts. It is suggested that copies of the Tårnby planking clamp might be used in future experimental boatbuilding projects.
© 2004 The Nautical Archaeology Society     

一种饱水木质文物含水率无损检测方法的研究

含水率是评估饱水木质文物糟朽程度最常用的物理参数之一。目前含水率检测常用方法有烘干法、电阻法、近红外光谱法等,但这些方法或属于破坏性分析,或检测范围不适用。为寻找一种适用于饱水木质文物含水率的无损检测方法,基于饱水木材组成理论模型,建立了含水率与湿态密度、灰分含量三者之间关系,进而提出一种检测含水率的便捷方法——溶液密度法。采用上述方法对天长、淮北等地出土饱水木质样品含水率进行测试,并与烘干法测得标准值进行验证。结果发现两者数据较为接近,相对误差在10%以内,证明了该方法的可靠性。进一步研究发现,样品越糟朽,使用该方法获取的数据与标准值之间相对误差越小。说明该方法更适用于糟朽饱水木材含水率的检测。     

云南剑川海门口遗址饱水古木降解的微观构造分析

文中采用扫描电镜(SEM)和透射电镜(TEM)对海门口遗址饱水古木进行降解机理分析。结果表明:古木细胞次生壁收缩严重并与胞间层分离;胞间层保存较完好,呈连续网状。说明古木纤维素和半纤维素降解相对严重,木质素降解相对较轻。古木主要是受细菌降解,通过SEM和TEM均可见明显的细菌腐朽特征。细菌首先侵入细胞腔,再通过S3层侵入细胞壁内部。细胞壁内由于降解而产生的空隙在几十到几百纳米之间。饱水古木也受到了一定程度的真菌降解,但这类真菌主要降解古木内淀粉等物质,对细胞壁物质降解能力差,主要是使古木变色。     

故宫太和殿二层斗拱竖向加载试验

为了更好地保护古建筑,采取静力试验方法,以故宫太和殿二层平身科、柱头科、角科斗拱为对象,研究了竖向荷载作用下斗拱的受力性能。基于上述3种斗拱构造特征,制作了1∶2比例模型,进行了竖向加载试验,讨论了不同斗拱在荷载作用下的破坏形式、内力及变形特征,归纳了斗拱的竖向刚度计算模型。结果表明:竖向荷载作用下,太和殿二层斗拱的坐斗及与之相交的头翘、正心瓜拱容易产生破坏,且模型倒置时下层构件受力要小于上层构件。对于不同斗拱而言,斗拱极限承载力:平身科角科柱头科;斗拱变形及残余变形量:柱头科角科平身科;斗拱延性:角科柱头科平身科。竖向荷载作用下,太和殿二层斗拱的竖向刚度计算模型可简化为三折线段形式。     

Responses of South African Agate and Chalcedony When Heated Experimentally,and the Broader Implications for Heated Archaeological Minerals

Here we present a database of responses by South African agate and chalcedony to heat treatment. This will assist analyses of heated stone tools not only in South African archaeological sites, but wherever heated agate and chalcedony pieces were knapped. The minerals are abundant worldwide. To replicate potential heating methods during the Stone Age we placed some minerals in a wood fire, some under coals, and others were buried in sediments beneath fires. Thermal responses include lustrous flaked surfaces, pot lid fractures, semi-circular internal fractures, rough internal surfaces, and crazing. Aerobic heating is implied by pot lid fractures. To explain the thermal responses we analyzed the minerals using X-ray fluorescence, Raman spectroscopy, and carbon and sulfur analyses. Our chalcedony contains more water and impurities than agate, making it more vulnerable to thermal damage. Our method of combining field experiments with chemical analyses has global applications even though we expect that mineral components of agate and chalcedony will vary slightly in different parts of the world.     

饱水木质文物的蔗糖保护法

本文概述了用蔗糖处理饱水木质文物的发展历史,并对蔗糖的脱水机理、防虫防霉处理、渗透效果等进行了阐００指出在饱水木质文物的保护方面,蔗糖是一种比较理想的保护材料。     

馆藏明代加彩木雕坐像保护前期研究

为更好地了解馆藏明代加彩木雕坐像的价值和病害情况,以期实施科学的保护和修复,利用超景深三维显微光学系统、拉曼光谱、红外光谱、X射线衍射、扫描电镜、X射线荧光能谱等分析方法对馆藏两件明代加彩木雕坐像的材质组成、制作工艺及病害情况等进行了综合分析。分析表明,两件木雕文物材质为樟科樟木属,加彩层为彩绘层,施彩工艺为先于木胎上打白灰层,而后铺一层纺织纤维,再于纤维布上涂颜料层,颜料层表面涂刷一层防护膜。其中,白灰层为石膏,纺织纤维为棉织物,所用颜料多为矿物颜料,蓝色显示物质为群青,黑色为炭黑,金色疑为铜金粉,而红色显色物质为植物染料-茜草。表面防护膜层为醇酸树脂。腐朽木材碎片和加彩层表面均有大量真菌孢子和菌丝,可以认为菌虫的侵染是引起木雕腐朽的主要因素之一。研究结果为更好地认识两件木雕文物,以及对其实施科学、有效的保护奠定了基础。