文献类型：期刊文献

英文题名：Moisture transfer and stress development during high-temperature drying of Chinese fir

作者：Zhou, Fan[1] Fu, Zongying[1] Zhou, Yongdong[1] Zhao, Jingyao[2] Gao, Xin[1] Jiang, Jinghui[1]

第一作者：周凡

通信作者：Fu, ZY[1];Fu, ZY[2]

机构：[1]Chinese Acad Forestry, Res Inst Wood Ind, Key Lab Wood Sci & Technol Status Forestry Adm, Beijing, Peoples R China;[2]Northeast Forestry Univ, Coll Mat Sci & Engn, Minist Educ, Key Lab Biobased Mat Sci & Technol, Harbin, Heilongjiang, Peoples R China

年份：2020

卷号：38

期号：4

起止页码：545-554

外文期刊名：DRYING TECHNOLOGY

收录：;EI(收录号：20191506748814);Scopus(收录号：2-s2.0-85063869980);WOS:【SCI-EXPANDED(收录号:WOS:000466031000001)】；

基金：This work was supported by the National Majority R & D Program of China [grant number 2016YFD0600701].

语种：英文

外文关键词：Chinese fir; high-temperature drying; moisture transfer; nuclear magnetic resonance; stress development

摘要：The knowledge of moisture content (MC) and drying stress are crucial parameters to control the drying process and maintain the quality of dried wood. Herein, we investigated the pattern of moisture transfer and stress development in Chinese fir during the high-temperature drying process. The MC in each layer of lumber was separated into bound water and free water via nuclear magnetic resonance (NMR), and the drying and residual stress were measured using prong test method. There was different MC in each layer along the thickness, resulting in an MC gradient that initially increased and then decreased, which is consistent with the trend of drying stress. The T-21 peak indicating bound water shifted to the left especially when MC was below the fiber saturation point, signifying that the discharge of moisture became difficult with prolonged drying time. The ratio of bound water to free water was different in each layer, indicating that the moisture transfer was different along the thickness. Furthermore, the residual stress was greater than the corresponding drying stress though the disparity reduced gradually, which suggests that the MC gradient was the largest affecting factor for drying stress at high MC stages but decreased to some extent as the drying process continued.