利用低温NMR技术测定木材及其热处理材纤维饱和点  

Determination of Treated and Control Wood on Fiber Saturation Point by Low-Field NMR Technology

作　　者：周凡丁[1] 高鑫[2] 蔡家斌[1] 庄寿增[1] 周洪杰[1] ZHOU Fan-ding;GAO Xin;CAI Jia-bin;ZHUANG Shou-zeng;ZHOU Hong-jie(College of Materials Science and Technology, Nanjing Forestry University, Nanjing 210037, China;Research Institute of Wood Industry,Chinese Academy of Forestry, Beijing 100091, China)

机构地区：[1]南京林业大学材料科学与工程学院,江苏南京210037 [2]中国林科院木工研究所,北京100091

出　　处：《波谱学杂志》2017年第1期108-114,共7页Chinese Journal of Magnetic Resonance

基　　金：江苏高校优势学科建设工程资助项目(PAPD)

摘　　要：实验基于核磁共振技术(Nuclear Magnetic Resonance,NMR)检测的无损性,利用低场NMR技术测定热处理前后花旗松的纤维饱和点(Fiber Saturation Point,FSP).在-3℃和25℃条件下,对CPMG(Carr-Purcell-Meiboom-Gill)脉冲测得的信号进行横向弛豫时间(T_2)分析,对比试样冷冻前后信号反演峰面积,确定试样吸着水饱和含量,得到不同热处理条件下花旗松的纤维饱和点依次为38.76%(对照材)、32.82%(180℃热处理)、29.40%(200℃热处理)、24.90%(220℃热处理).实验结果表明,热处理温度越高,纤维饱和点越低.该结果测试结果与木材学理论相符,表明NMR技术可应用于快速确定木材纤维饱和点.Due to its non-destructive characteristic, nuclear magnetic resonance (NMR) spectroscopy was used to study the fiber saturation point (FSP) of Pseudotsuga menziesii before and after heat treatment. The bound water amount in saturated wood cell wall was determined by analysis of T2 relaxation time distributions measured using GPMG (Carr-Purcell-Meiboom-Gill) sequence at -3 ℃ and 25 ℃. Results showed that the FSP of Pseudotsuga menziesii treated with various temperatures are 32.82% (180 ℃), 29.40% (200 ℃), 24.90% (220 ℃) and 38.76% (untreated), which indicate that FSP of Pseudotsuga menziesii decreases with increased heat treatment temperature. This study reflects that NMR could provide detailed information about wood water distribution rapidly and efficiently.

关 键 词：核磁共振(NMR) 热处理 纤维饱和点(FSP) 横向弛豫时间(T2) 

分 类 号：O482.53[理学—固体物理]