作者：熊婷¹, 张鞠成¹, 徐盼盼¹, 张英力²

作者单位：1. 中国计量学院信息工程学院, 浙江 杭州 310018;
2. 上海纽迈科技有限公司, 上海 200333

关键词：含糖量; 低场核磁共振; 自由感应衰减信号; 横向弛豫时间

摘要：

采用20 MHz低场核磁共振弛豫谱分析技术检测苹果不同部位的蔗糖含量,研究含糖量与核磁共振信号之间的关系;利用CPMG序列来测溶液的T2值,得到含糖量和溶液中所含糖信号量的定标线,并用此定标线对苹果不同部位的含糖量进行定量分析。实验结果表明:含糖量的多少不仅影响自由感应衰减信号(free-induction decay signal, FID)的大小,而且影响其横向弛豫时间(T2)和纵向弛豫时间(T1);随着含糖量的升高,样品的自由感应衰减信号呈线性增大(r20.94);靠近果核部位的苹果组织含糖量最高,靠近果皮的最低,这与核磁共振波谱分析测试的结果相同,证明了此标线的可行性和准确性。

Application of nuclear magnetic resonance on detecting sucrose content in different parts of apple

XIONG Ting¹, ZHANG Ju-cheng¹, XU Pan-pan¹, ZHANG Ying-li²

1. College of Information Engineering, China Jiliang University, Hangzhou 310018, China;
2. Shanghai Niumag Corporation, Shanghai 200333, China

Abstract: A 20 MHz nuclear magnetic resonance (NMR) system was used to measure the NMR relaxation spectrum in different parts of the apple and studied the relationship between sugar content and NMR signal. Moreover, the Carr-Purcell-Meiboom-Gill (CPMG) technique was used to measure T₂ and control the water signal in manganese chloride aqueous solution. Then, the calibration line was used to test the sugar content in apple tissues. Finally, a calibration line of the sugar content and the value of sugar signal were determined. The results show that sugar content influences not only FID but also transverse relaxation time and longitudinal relaxation time; FID signal increases with the increasing of sugar content and the relationship is linear(r²>0.94); tissues close to the core have the highest sugar content and close to the skin are the lowest, this results are the same as the NMR spectrum analysis and prove the feasibility and veracity of the calibration line.

Keywords: sucrose content; low-field nuclear magnetic resonance; FID; transverse relaxation time

2014, 40(4): 33-36  收稿日期: 2013-6-24;收到修改稿日期: 2013-8-6

基金项目: 国家质检公益行业科研资助项目(201210079)

作者简介: 熊婷(1988-),女,江西高安市人,硕士研究生,专业方向为信号与信息处理。

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