饱水木质文物的风冷干燥脱水研究

许多出土饱水木质文物因其降解严重、含水率较高,容易在脱水过程中出现不可逆的收缩变形以及开裂现象,从而遭到严重破坏。因此,饱水木质文物脱水方法的研究是文物保护工作中的重要课题。为探究风冷冷冻法对饱水木质文物脱水的效果,以一批无法复原的出土饱水木质文物为研究对象,在对其材种、含水率、基本密度及化学成分进行了测定和分析后,使用一台风冷电冰箱在-18℃条件下对样品进行了风冷干燥脱水处理,记录脱水时间和脱水效果,并分析了该方法的传质传热特点,证明了风冷干燥法用于饱水木质文物的脱水干燥能够取得良好效果,并且具有对文物干预小、适用性广、操作简便、成本低廉等优点,为饱水木质文物的脱水处理提供了一种新的思路。     

RECENT ENVIRONMENTAL CHANGE IN THE SOUTHWESTERN CANADIAN PLAINS

This paper examines 20th-century environmental change in the subhumid southwestern Canadian Plains, specifically in relation to the dominant agricultural landscape and to the climate of the past millennium as reconstructed from proxy data. Anthropogenic landscape change in the last century has been dominated by the conversion of grasslands to ranchland and cropland. This has heightened landscape vulnerability to climatic fluctuations, especially drought. Instrumental climate records, extending back to the 1880s, highlight the variability of precipitation in this region. Proxy environmental records, derived from lake cores and tree-ring analysis, extend this picture into the last millennium and show that drought has been a recurring theme of the Prairie climate. Tree-ring records suggest that some droughts in the last millennium may have exceeded in severity any in the instrumental record. The sustainability of Prairie agriculture depends on adaptation to the amplitudes of climatic change and variability evident in these proxy records. Dans cet article nous examinons les changements environnementaux qui sont survenus pendant le 20^ème siècle dans les plaines canadiennes sèches du sud-ouest, spécifiquement par rapport au paysage agricole dominant et au climat du dernier millénaire qui a été déterminéà partir de données de procuration. La transformation des prairies en ranchland et cropland est le changement du paysage le plus important dont l'homme est responsable, pour le dernier siècle. À cause de ce changement, le paysage est plus vulnérable aux fluctuations climatiques - à la sécheresse en particulier. Les enregistrements instrumentaux de climat, qui reculent jusqu'aux années 1880, mettent en évidence la variabilité des précipitations dans cette région. Les enregistrements environnementaux de procuration, dérivés d'échantillons pris dans les lacs et de la dendroanalyse, étendent cette image dans le dernier millénaire et prouvent que le thème de la sécheresse est apparu souvent dans les analyses du climat du prairie. Les enregistrements de boucles d'arbre suggèrent que, dans le dernier millénaire il y avait des sécheresses qui étaient peut-être si sévères que les instruments n'ont pas pu les enregistrer. Si l'agriculture veut survivre comme entreprise dans les prairies, il faudra qu'elle s'adapte aux amplitudes de changement et de variabilité du climat qui ont été constatées dans les données de procuration.     

毛奇龄《古文尚书冤词》探微

《古文尚书》辨伪是清代学术史上的重要课题。清初学者阎若璩作《尚书古文疏证》,判定今本《古文尚书》为伪书,而同时代的学者毛奇龄则作《古文尚书冤词》,极力为《古文尚书》辩护,从而引发了一：场学术公案。《古文尚书》之伪,今日已成定论。《冤词》成为毛氏学术生涯中的败笔,其结论本身已无价值可言。但是他在论辨当中崇实黜虚,纠正了不少辨伪者的错误,从学术史的角度讲,这部表面看起来与辨伪针锋相对的《冤词》,恰恰对《古文尚书》辨伪的深入产生了重要影响。     

Recent archaeobotanical investigations into the range and abundance of Neolithic crop plants in settlements around Lake Constance and in Upper Swabia (south-west Germany) in relation to cultural influences

An overview is presented of the cultivated plants found at Lake Constance (Bodensee) and in the Upper Swabia region including the Federsee (Baden-Württemberg/south-west Germany) between 4000 and 2400 cal BC. This work relates to recent archaeobotanical investigations of the waterlogged sediments of 30 different Neolithic lakeside settlements. These sites provided almost 500,000 crop plant macro-remains, excellently preserved under waterlogged conditions. Taken in conjunction with other previously collected samples from the region, they provide an added dimension to the understanding of crop plant development in the lakeshore Neolithic in south-west Germany.     

Producing liminal space: gender,age and class in northern Ontario's tree planting industry

Drawing upon qualitative data, this article examines how tree planters in northern Ontario, Canada engage with liminality in terms of gender, class, age and space. In doing so, it provides insight into concepts of gender liminality and the variegated experiences of males and females in liminal space. The article focuses on four aspects of the liminal engagement. First, the spaces of tree planting are liminal as they are marked by homelife and worklife, but dominated by neither. Second, gender performances are liminal, as males perform masculinities seldom necessary or appropriate – yet often valorized – in their permanent communities, while females (who make up nearly half of the workforce) are offered opportunities to work and succeed in a traditionally male industry. However, success often requires that they adopt certain masculine traits. Third, most tree planters are in the interstitial age of ‘youth’, somewhere between adolescence and adulthood. Finally, tree planters are generally members of affluent urban middle-classes, yet the work they perform is more readily associated with rural or peripheral working-classes.     

Roman landscape and agriculture on the Ligurian coast through macro and microremains from a Vada Sabatia well (Vado Ligure,Italy)

Abstract

The results of an analysis on plant remains (fruit, seeds, pollen and wood) found in sediments in a Roman well in Vada Sabatia (Vado Ligure, Liguria, Italy), dated between the first and fourth centuries AD are presented. The remains are well preserved and constitute an exceptional record of the Ligurian area. Five layers have been recognised: three corresponding to the well when in use and two to the well when it was no longer in use. The vegetational cover of the area has been found to be similar to that observed in the coastal plain near Albingaunum (Albenga) pertaining to the same period. Moreover, the two superficial layers have cumulated a large amount of macroremains related to the period in which the well was no longer in use. The principal tree and vegetable crops and cereals of the coastal plain were present, due to the influence of maritime and mercantile trade, as were the prevailing ruderal and weed species and the tree cover. The presence of carpological remains of Castanea sativa, Secale cereale, Beta vulgaris and Cucumis sativus is reported for the first time in the Roman Age in Liguria. The influence of the arrival of the Romans can be seen from new crops, such as Prunus persica, and the introduction of exotic fruit like Phoenix dactylifera and Ziziphus jujuba. Several wooden artefacts, for example, a rack for drying lucerne and a tool handle, made of Cornus or Viburnum and Viburnum cf. lantana respectively, have been found. The well has proved to be an ideal location for the preservation of plant remains compared with other studied archaeological situations in Liguria and in Southern France, as it presents a higher variety of cultivated fruits, vegetables and cereals.     

温度和湿度对乙二醛聚合物加固饱水梓木文物性能和微观结构的影响

乙二醛聚合物加固饱水梓木文物在自然环境或者博物馆存放时,受环境因素如温度和湿度的影响会导致文物发生劣化。本研究采用傅里叶红外光谱(FTIR)、扫描电镜(SEM)等方法研究了乙二醛聚合物脱水加固饱水梓木试样在不同温度和湿度环境中性能与微观结构变化。结果显示,饱水梓木文物材料经乙二醛聚合物脱水加固后,乙二醛聚合物与梓木细胞壁结合紧密,部分填充于梓木细胞内加固梓木细胞壁。试样在25℃和50%RH环境中试验30 d其结构和性能无明显变化。在60℃和50%RH环境中试验30 d,试样内部的乙二醛聚合物逐渐均匀附着于细胞壁且表面平滑,试样横截面断口平整;但试样表面的乙二醛聚合物逐渐消失,暴露出木材本体。在25℃和95%RH环境中乙二醛聚合物吸湿性明显增强,其与水的结合能力高于梓木细胞壁,乙二醛聚合物与细胞壁之间的结合被破坏,失去加固效果,但仍填充于细胞中。最后分析了温湿度对乙二醛聚合物加固饱水梓木性能与结构的影响机制,并提出了试样在吸湿和脱水过程中乙二醛聚合物与梓木细胞壁的结构变化模型。     

三星堆一号青铜神树的三维数字建模与静力学分析

结构稳定性是评估文物安全的重要方面。三星堆二号坑出土1号青铜树体量庞大、结构复杂,且存在腐蚀、裂纹等危险因素,为了充分记录、评估其保存状况,本研究在原始几何形状和内部构造的基础上,利用三维数字建模技术,建立其几何模型和数值模型,并估算出青铜神树的质量分布和质心位置等无法实地测量的数据,并使用有限元方法,从应力和位移的角度分析青铜树的静置状态下的安全性。经过有限元模拟和材料力学简化计算,发现龙身和树干连接处、树枝根部应力较大,是易受损区域。     

Phenol Formaldehyde Revisited—Novolac Resins for the Treatment of Degraded Archaeological Wood

Archaeological wood is usually severely degraded. The Norwegian Viking Age Oseberg find exemplifies problems arising due to past conservation treatments and the need for new types of preservatives. Phenol formaldehyde (PF) has been investigated as a consolidant for alum‐treated wood. X‐ray tomography has revealed that it is possible to obtain a porous structure inside the wood, ensuring ethical acceptability by allowing re‐treatment. In order to understand the curing mechanics, the kinetics of the initial condensation reaction were elucidated at room temperature. It was found that a second‐order reaction using both phenol and formaldehyde concentrations is the most probable mechanism.     

出土饱水木质文物的微生物腐蚀及防腐措施

在南方保存完好的出土木质文物大都处于饱水状态.出土后因为水和氧气的参与,在水解作用、微生物腐蚀等诸多因素的作用下,木质文物逐步被降解而变得腐朽.为此,本文从木质文物的微生物腐蚀机理着手,提出控制水活度的办法、控制氧气量、毒化微生物赖以生存的养料三种途径来防止或延缓木质文物的腐朽,以等待将来更好的脱水定型方法出现.