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Pontamine fast scarlet 4B is a red paper and textiles dye that has recently been introduced as a fluorescent probe for plant cell walls. Pontamine exhibits bifluorescence, or fluorescence dependent on the polarization of the excitation light: Because cellulose is aligned within the cell wall, pontamine-labelled cell walls exhibit variable fluorescence as the excitation polarization is modulated. Thus, bifluorescence measurements require polarized excitation that can be directly or indirectly modulated. In our confocal microscopy observations of various cellulose samples labelled with pontamine, we modulated excitation polarization either through sample rotation or by the confocal's scanfield rotation function. This variably rotated laser polarizations on Leica confocal microscopes, but not those from other makers. Beginning with samples with directly observable microfibril orientations, such as purified bacterial cellulose, the velamen of orchid roots and the inner S2 layer of radiata pine compression wood, we demonstrate that modelling the variations in pontamine fluorescence with a sine curve can be used to measure the known microfibril angles. We then measured average local microfibril angles in radiata pine samples, and showed similar microfibril angles in compression and normal (opposite) wood. Significantly, bifluorescence measurements might also be used to understand the degree of local cellulose alignment within the cell wall, as opposed to variations in the overall cellulose angle. [ABSTRACT FROM AUTHOR]

Abstract: Concern about fatigue is one of the factors limiting use of glass/epoxy jointing systems for timber in construction. In this paper, a series of high-cycle fatigue tests are reported which indicate that the performance is as good, if not superior to, conventional jointing systems. The performance of the joints was found to produce a straight line on a logarithmic S–N plot and thus be readily predictable for design purposes. [Copyright &y& Elsevier]

Whilst forest management certification emerged in the early 1990s as a potential market-based solution to the problem of forest loss and degradation, certified timber has not yet taken a significant share of timber and wood product markets. Although the lack of supply of certified timber is acknowledged as a problem, market barriers to the uptake of certified products are poorly understood. This study sought to identify and compare barriers to the uptake of certified wood and wood products in the UK's paper and construction industries. Findings indicate marked variation in barriers between individual companies and between the industries. Key barriers identified include: organizational constraints – strategic commitment, inadequate systems, staff skills and financial provision; supply constraints – material availability, supply chain complexities, entrenched supplier relationships; and demand constraints – lack of knowledge, weak demand, price sensitivity, traditional expectations and availability of substitutes. Ways to overcome these barriers are discussed. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment. [ABSTRACT FROM AUTHOR]

Goal, Scope and Background. This paper gives an overview on how the wood and packaging material production is inventoried in ecoinvent. Packaging materials have been a very important topic in the area of Life Cycle Assessment for more than twenty years. Wood is the most important renewable material and regenerative fuel used worldwide, and an important raw material for paper I board. Several methodological problems arising when inventorying wood for material and energetic uses in a generic database are discussed in more detail. Within the ecoinvent project, the Swiss data base for life cycle inventory data, two reports are dedicated to these two important topics - report No. 9 for wood and report No. 11 for packaging materials. Methods. The whole wood chain has been modeled in a consistent way. This allows one to use this data for LCAs of building materials, bioenergy or paper production. The data represent average technologies used in Central Europe in the year 2000. A revenue-based co-product allocation approach is used for the different outputs. Correction factors are introduced for the consistent modeling of mass-based, material inherent wood properties such as solar energy, carbon uptake and land use. For packaging materials, the data sets represent European average data for the most often used materials as well as specific datasets for the production of actual packaging boxes and containers. Results and Discussion. For wood, revenue-based allocation and the use of the correction factors for mass-related wood properties are shown and explained. For packaging materials, the importance of the raw material wood to the total load is shown. Furthermore trends in the data inventories for board packaging materials over the last two decades are discussed: mainly due to the increased comprehensiveness of the data, higher cumulative emissions can be observed. Conclusion. For wood, the database ecoinvent provides consistent data sets for the entire chain from forestry to intermediate products such as timber, different types of wood based boards, chips, pellets, etc. For packaging materials, the number of data sets of basic materials has been extended. A modular concept for actual packaging container data sets allows the user an easy modeling of various types of packaging containerslboxes. In the area of paper and board, a comprehensive database for the production of various types of pulp, paper and board is provided, which is representative for the average European production situation. Outlook. Since wood is only limited and representative data for Europe is therefore not included, an update in the near future would be reasonable. Possible further extensions in the future could include various, final wooden products. For the data on paper/board, different levels of quality are observed, requiring a selective up-date of these data. Future extensions could include data sets for the import of pulp from overseas - especially from South America and Canada. [ABSTRACT FROM AUTHOR]