Application of the ESEM Technique in Wood Research. Part II. Comparison of Operational Modes
Keywords:Wood, SEM, ESEM, wood structure, fractography
An ESEM (Environmental Scanning Electron Microscopy) technique has been applied to wood objects. ESEM investigations were performed through several operational modes that offer various sets of environmental and imaging conditions. The comparison of ESEM micrographs with conventional SEM images revealed specific advantages and shortcomings of the ESEM technique in studies on genuine and painted wood objects. Merits of the application of ESEM technique for wood are related to the absence of preparation artifacts, such as sputtering irregularities or defects due to shrinkage in vacuum drying. Great ESEM advantage over high-vacuum SEM, such as conduction of dynamic experiments within the chamber, is illustrated with a sequence of condensation, freezing, and drying on a wood specimen.
The wood imaging using ESEM proved inferior to that of conventional SEM in terms of lower magnification, sharpness, and contrast. However, the article offers guidance for assessment of influential operating parameters and their selection for the optimization of the ESEM work with wood. It may result in micrographs of sufficient resolution, definition, and optical quality for study of wood structure on cellular and even intra-cellular level.
Derbyshire, H., E. R. Miller, and H. Turkulin. 1995. Investigations into the photodegradation of wood using microtensile testing. Part 1: The application of microtensile testing to measurement of photodegradation rates. Holz Roh-Werkst.53(4):339-345.nDerbyshire, H., E. R. Miller, and H. Turkulin. 1996. Investigations into the photodegradation of wood using microtensile testing. Part 2: An investigation of the changes in tensile strength of different softwood species during natural weathering. Holz Roh-Werkst.54(1):1-6.nGu, H-M., A. Zink-Sharp, and J. Sell. 2001. Hypothesis on the role of cell wall structure in differential transverse shrinkage of wood. Holz Roh-Werkst.59:436-442.nTurkulin, H., and J. Sell. 1997. Structural and fractographic study on weathered wood. An application of FE SEM microscopy to the "Thin strip" method. Research and work report No. 115/36. Swiss Federal Laboratories for Materials Testing and Research (EMPA). Dübendorf, Switzerland. 40 pp.nTurkulin, H., and J. Sell. 2002. Investigations into the photodegradation of wood using microtensile testing. Part 4: Tensile properties and fractography of weathered wood. Holz Roh-Werkst.60(2):96-105.nTurkulin, H., K. Richter, and J. Sell. 2002. Adhesion of waterborne acrylic and hybrid paint on wood treated with primers. Surface Coatings Internat. Part B: Coatings Transactions Vo. 85, B4, 273-280.nTurkulin, H., L. Holzer, and J. Sell. 2004. Application of the ESEM technique in wood research. Research and work report No. 115/51. Swiss Federal Laboratories for Materials Testing and Research (EMPA), Dübendorf, Switzerland. 58 pp.nTurkulin, H., L. Holzer, K. Richter, and J. Sell. 2005. Application of the ESEM technique in wood research. Part 1: Optimization of imaging parameters and working conditions. Wood Fiber Sci. (in press).nZimmermann, T., and J. Sell. 1997. Die Feingefüge der Zellwand auf Querbruchflächen von längszugbean-spruchten Laubhölzern. Research and work report No. 115/35. Swiss Federal laboratories for Materials Testing and Research (EMPA), Dübendorf, Switzerland. 37 pp.nZimmermann, T., and J. Sell., and D. Eckstein. 1994. Rasterelektronen-mikroskopische Untersuchungen an Zugbruchflächen von Fichtenholz. Holz Roh-Werkst.53(4):223-229.n
The copyright of an article published in Wood and Fiber Science is transferred to the Society of Wood Science and Technology (for U. S. Government employees: to the extent transferable), effective if and when the article is accepted for publication. This transfer grants the Society of Wood Science and Technology permission to republish all or any part of the article in any form, e.g., reprints for sale, microfiche, proceedings, etc. However, the authors reserve the following as set forth in the Copyright Law:
1. All proprietary rights other than copyright, such as patent rights.
2. The right to grant or refuse permission to third parties to republish all or part of the article or translations thereof. In the case of whole articles, such third parties must obtain Society of Wood Science and Technology written permission as well. However, the Society may grant rights with respect to Journal issues as a whole.
3. The right to use all or part of this article in future works of their own, such as lectures, press releases, reviews, text books, or reprint books.