Abstract
The migration of bound water and free water has been investigated during microwave drying of wood by the time domain nuclear magnetic resonance (TD-NMR) technique. Both the heartwood (hW) and sapwood (sW) of Beijing poplar (Populus beijingensis W. Y. Hsu) and Qingpi poplar (Populus platyphylla T. Y. Sun) were studied. The microwave drying is characterized by a fast drying rate, and there is a linear relation between moisture content (MC) and microwave drying time (t). The drying rate of free water is about 2.7 times more rapid than that of bound water. The spin-spin relaxation time (T2) revealed that most of the water was free water situated in smaller pores. The irregular T2 signal amplitudes of free water in hWs indicated that fractional water in smaller pores was transferred into bigger pores during drying.
Acknowledgments
This research was supported by the National Natural Science Foundation of China (31160141/C1603), the China Scholarship Council and the Natural Science Foundation of Inner Mongolia (2015MS0351).
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©2017 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Original Articles
- Cationized fibers from pine kraft pulp: advantages of refining before functionalization
- Tracking the geographical origin of timber by DNA fingerprinting: a study of the endangered species Cinnamomum kanehirae in Taiwan
- Reduction of biomass resilience by torrefaction: apparent stiffness during failure (ASF) and specific failure energy (SFE) assessed by a custom impact device
- Improvement of shear strength, wood failure percentage and wet delamination of cross-laminated timber (CLT) panels made with superheated steam treated (SHST) layers of larch wood
- Water migration in poplar wood during microwave drying studied by time domain nuclear magnetic resonance (TD-NMR)
- The minimum moisture threshold for wood decay by basidiomycetes revisited. A review and modified pile experiments with Norway spruce and European beech decayed by Coniophora puteana and Trametes versicolor
- Effect of volatile organic compounds from Pinus sylvestris and Picea abies on Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae and Salmonella enterica serovar Typhimurium
- Effect of ozonation on composting Japanese cedar wood meal
- Short Note
- Four-point key-hole side-edge-notched bending (4KHSENB) strength of medium-density fibreboard
Articles in the same Issue
- Frontmatter
- Original Articles
- Cationized fibers from pine kraft pulp: advantages of refining before functionalization
- Tracking the geographical origin of timber by DNA fingerprinting: a study of the endangered species Cinnamomum kanehirae in Taiwan
- Reduction of biomass resilience by torrefaction: apparent stiffness during failure (ASF) and specific failure energy (SFE) assessed by a custom impact device
- Improvement of shear strength, wood failure percentage and wet delamination of cross-laminated timber (CLT) panels made with superheated steam treated (SHST) layers of larch wood
- Water migration in poplar wood during microwave drying studied by time domain nuclear magnetic resonance (TD-NMR)
- The minimum moisture threshold for wood decay by basidiomycetes revisited. A review and modified pile experiments with Norway spruce and European beech decayed by Coniophora puteana and Trametes versicolor
- Effect of volatile organic compounds from Pinus sylvestris and Picea abies on Staphylococcus aureus, Escherichia coli, Streptococcus pneumoniae and Salmonella enterica serovar Typhimurium
- Effect of ozonation on composting Japanese cedar wood meal
- Short Note
- Four-point key-hole side-edge-notched bending (4KHSENB) strength of medium-density fibreboard