A Method for Wood Preservation using Arigal C

Abstract

The coating on a stoneware plate damaged in a fire was found to be PVA contaminated with carbon particles. After solubility tests, dilute sodium hydroxide was selected to dissolve the coating.     

Risk Assessment and Preservative Measures for Volatile Organic Compounds in Museum Showcases

ABSTRACT

The first step in preservative measures for artworks in airtight showcases is the exclusion of outgassing from construction materials or, at least, limitation of the emissions to a minimum acceptable level if the volatile organic compounds (VOCs) generated may be qualified as harmless. Once it is ascertained that the objects in the showcases are responsible for VOC emissions, a step forward becomes necessary, implying showcase ventilation with air flowing through active sorbent materials. Solid phase micro-extraction (SPME) followed by GC separation and MS identification has been applied for checking the outgassing characteristics of different types of materials used for the construction of airtight showcases, and the method was found particularly attractive in terms of speed and sensitivity, suitable for measurements in presence of low-emitting materials. Sampling could also be done in the case interiors, thus making possible detection and recognition of emissions from art objects within a case. A comprehensive preventive conservation scheme has been further devised by means of active air circulation within the showcase and functional sorbent materials along the flow, for complete suppression of gaseous compounds. Control of the compounds in the air flow and of their filtration efficacy was achieved by direct sampling, also using SPME fibers. Continuous monitoring of the air quality in the showcases has been developed with insertion of a photoionization detector capable of detecting the VOCs in the air by inducing molecular ionization, and measuring the generated photocurrent. The system is not selective, but gives the total concentration, reaching ppb sensitivity with high-quality data. In addition it includes temperature and humidity sensors, making the whole a useful instrument for environment control.     

Insect-Infested Wood Remediation by Microwave Heating and Its Effects on Wood Dehydration: A Case Study of Hylotrupes bajulus Larva

Wood artefacts are subject to damage by biologic infestations due to bacteria, insects, and fungal species. One of the worst feared attacks is due to the xylophagous insects whose larvae feed on wood by boring galleries, at the expense of building timbers and worked woods. These beetles are responsible for daily destruction of the world’s wooden cultural heritage, and their elimination has been always a big problem for conservation of wood. The need to avoid the use of chemical methods in conservation for pest control has led to the development of various non-chemical, non-toxic treatments. Among these, heating with microwaves (MW) seems to be one of the most promising, since it has already shown its high efficacy in destroying pests. Insect-infested wood remediation by MW heating in conservation is based on the larger thermal increment induced in larvae than in wood, due to their different dielectric permittivity in the GHz frequency range. However, the side effects that may occur due to MW heating of wood, such as dehydration, have never been discussed so far. Here we study the possible application of microwave heating as a remediation method for wood samples infested by the larvae of the insect Hylotrupes bajulus. We show that it is possible to set up exposure conditions able to achieve 100% of larvae death and that are sufficiently mild not to induce significant dehydration of the exposed wood from which shrinkage effects may derive. Indeed, under these conditions, MW-induced wood dehydration on cubic and parallelepiped sweetgum samples can be kept under control and to percentages as low as 0.4% (w/w).     

Technologies for Wood Preservation in Historic Preservation

Because of the abundant forests of the world, wood is one of the most common materials found in historic buildings. Wood is relatively easy to fabricate into beams, columns, and roof systems using simple hand tools. However, because of its biological origin, wood is one of the most complex constructions materials. It is produced by thousands of different species of trees, and each type of wood has unique properties. Wood has an affinity for moisture and this can lead to biological deterioration caused by insects and decay fungi. This chapter presents information on understanding and preventing the mechanisms of wood deterioration in historic buildings. The chapter includes a discussion of wood preservation and technology, including wood finishes and wood preservative treatments, diffusible preservatives, and naturally durable wood species. A brief discussion about the repair of deteriorated timbers in buildings is also included.     

高校OA系统电子文件的归档及保管方式

据笔者抽样对全国高校的调研情况统计分析,目前各高校OA系统与档案管理系统使用的实际状况主要有:一、OA系统与档案管理系统分头建设;二、OA系统与档案管理系统统一建设;三、OA系统未建设或因故已停用,档案管理系统独自运行.     

明代与文艺复兴时期木版插图的比较

明代是中国木版插图的鼎盛时期,木刻版画一直是明代插图制作的主要形式,而欧洲木版插图的兴起、鼎盛和衰落贯穿了整个文艺复兴时期.这两个在时间上平行的时代在木版插图领域有着许多相似之处,但又受政治、经济、文化、审美等方面因素的影响有着不同的发展路径.本文通过平行比较的研究分析,试图找出两地木版插图的差异性及不同发展走向的内在原因.     

藏文档案常用藏纸的纤维及其造纸工艺对比分析

西藏手工纸是中国传统造纸工艺的重要组成部分,藏纸档案文献也具有极高的科学研究价值,本文从纤维组成和微观分子结构角度,通过显微观察、红外分析和元素测定等方法,对1份约700年前的古代档案藏纸和5种现代藏纸的纤维理化性质和元素成分进行研究.确定现代拉达克、尼木、不丹和金东藏纸主要由瑞香或结香属的纤维构成,古代藏纸和现代金东...     

韦棣华基金会与中国图书馆事业的发展

192 0年韦棣华女士在武昌创办中国第一所图书馆学校 ,1 930年又以捐款为基础成立韦棣华基金会。 1 997年 ,在吴文津先生和杜克先生的斡旋下 ,韦棣华基金会在中国大陆设立“韦棣华奖学金” ,资助众多图书馆学、情报学专业的学子完成学业。表 1。参考文献 8。     

Carbowax and Other Materials in the Treatment of Water-logged Paleolithic Wood

Abstract

Infra-red reflectography, a method of improving the detectability of underdrawings in medieval paintings, is discussed. It is shown that the results can be explained with the Kubelka-Munk analysis of the optical properties of paint films. Measurements are described providing a plot of the paint layer thickness required to hide an underdrawing, against the wavelength.

Such curves show a maximum around λ = 2.0 microns. Infra-red to visible image translation systems are surveyed to illustrate the choice of an infra-red vidicon television system to obtain reflectograms. This system is responsive to radiation up to 1.9 microns. The interpretation of infra-red reflectograms is briefly discussed. Limitations of the method are indicated.     

韦棣华与中国图书馆学的渊源

被誉为“中国图书馆学皇后”的韦棣华女士,是我国图书馆学的先驱人物。在中国,她筹建图书馆,创建“文华公书林”和中国第一所独立的图书馆学校;她引进了美国的公共图书馆精神,开启了中国图书馆学的大门,开创了中国图书馆学教育之先河,并促成了中国图书馆学的产生和发展。在她身上,体现了对图书馆事业高度的忠诚与热爱,体现了一种敢为人先、克己敬业、无私奉献的精神,这是医治当代中国图书馆界浮躁之风的一剂良药,更是支撑中国图书馆事业健康发展、激励图书馆人为图书馆事业不断奋斗的图书馆精神。     

引进一棵树成活一片林--谈出版社如何利用版权贸易快速发展

2003年的中国出版业面临着极好的机遇和巨大的挑战。机遇来自国家对出版产业发展的政策支持。有条件的外部资金准入和对民营企业的肯定都会对中国出版业的发展起到极大的促进作用。然而面对已经和将要进入中国的国外媒体大鳄的竞争,留给中国出版业养精蓄锐、迅速成长     

Dimensional Stability and Moisture Properties of Gap-Fillers Based on Wood Powder and Glass Microballoons

ABSTRACT

Conservation of wooden objects exposed outdoors is extremely difficult and complex due to their constant exposure to fluctuating weather conditions and biological degradation. Filling the gaps in such objects requires the use of specific materials that in particular can adapt to changes in wood dimensions in response to humidity variations. Various materials have been used so far for filling voids in wooden artefacts but none of them was entirely suitable. Therefore, the authors have attempted to provide the basic characteristics of the selected commonly used filling materials based on pine wood powder or glass microballoons as fillers and Paraloid® B-72, Klucel® G, or glutin glue as binders, as the first step in research aiming at developing new and more appropriate gap-fillers. Special attention was paid to the dimensional stability of filling materials upon drying and exposure to water vapour and liquid water. The overall results indicate that among the examined fills those consisting of Paraloid® B-72 and glass microballoons revealed best properties as they were relatively dimensionally stable upon drying and exposure to moisture – despite high absorption of water – and were quite easy to finish. Generally, better properties were observed for filling materials containing higher concentrations of adhesives and these materials will be modified in the next step of the research. Since the main drawbacks of the examined gap-fillers were low water resistance, poor dimensional stability upon drying or exposure to water vapour or liquid water, and fragility or friability, future research into their modification will head towards improvement of the above-mentioned properties.     

谈《中图法》"TS6木材加工工业、家具制造工业"类

本文是对<中图法>(三版)中TS6类目提出的修订建议.文中阐述木材加工工业与林业和森林采运工业的相关关系,分析了木材加工工业的学科结构,指出了第三版该类目的一些误点与不足,尝试性地对TS6类目作了试展开.     

FTIR Measurement of Cellulose Microfibril Angle in Historic Scots Pine Wood and Its Use to Detect Fungal Decay

Microfibril angle (MFA) – the orientation of cellulose fibres in the S2 layer of the secondary cell wall – is a key determinant of the stiffness and strength of timber. The microfibril angle depends on the way in which the timber was grown and its position within the tree. Microfibril angle can be measured by X-ray diffraction and other methods, but the methods in current use are slow or require advanced instrumentation. The aim of this study was to explore the use of polarised Fourier transform infrared (FTIR) microscopy as a relatively fast and inexpensive method for measuring MFA in historic Scots pine (Pinus sylvestris L.). The FTIR measurements were calibrated against X-ray measurements of MFA in modern Scots pine. We observed a wide range in MFA values and a radial pattern of MFA similar to modern Scots pine in undecayed Scots pine heartwood from sixteenth and seventeenth century beams in Scottish secular buildings. The density of the heartwood was also similar to modern plantation-grown Scots pine despite the much slower growth rate recorded in the ring widths of the historic timber. The sapwood, which had been attacked by both insect pests and fungi, showed an erratic reduction in density and a large increase in MFA compared to the modern material. The increased sapwood MFA was attributed to selective destruction of the S2 layer of the wood cell walls by fungal decay. Using MFA measurements in conjunction with density offers the possibility to estimate the mechanical properties of sound historic pine timber, to detect fungal decay more sensitively than by density alone, and to distinguish between pest and fungal attack in a way that relates directly to the remaining mechanical performance of the timber.