摘要
熔盐具有优异的传热和储热性能,被广泛应用于核能和太阳能等领域。核磁共振技术(Nuclear Magnetic Resonance,NMR)是研究熔盐微观结构的有力工具。由于商业化标准核磁样品池顶端设计有排气孔的存在,不适用于一些具有挥发性、毒性或放射性的熔盐体系的研究。针对该难点,以AlN、BN和Al_(2)O_(3)陶瓷材料为内管,ZrO_(2)陶瓷材料为外管,设计了一种新型密封性NMR样品池,以满足不同类型熔盐体系的测试要求。此外,利用KBr样品的^(79)Br化学位移与温度的关系,对新设计的多种样品池进行了温度标定。经测试,自主设计的样品池适用于熔盐体系的最高温度为700℃,可满足大多数熔盐系统检测的要求。使用该样品池进行了高温熔盐NMR信号测试,验证了其适用于熔盐体系的可靠性。
[Background]Molten salt systems have been extensively applied in the generation of nuclear and solar energy owing to their excellent heat transfer and storage performance.Therefore,it is essential to explore their physical and chemical properties,which are largely determined by their composition and ionic structure.In this regard,high-temperature(HT)nuclear magnetic resonance(NMR)has been demonstrated as an effective solution for qualitative analysis.Due to the existence of vent holes on the top of the commercialized standard NMR sample cell,it is not suitable for the study of some volatile,toxic or radioactive molten salt systems.[Purpose]This study aims to implement ceramic NMR sample cells that are suitable for different molten salt systems.[Methods]Firstly,a novel sealed sample cell that meets the requirements of molten salt systems was designed and produced by using an inner tube comprising AlN,BN,and Al_(2)O_(3) ceramic materials,and an outer tube composed of ZrO_(2) ceramic materials.Then,with KBr as the standard sample,temperature calibration for this sample cell was conducted on the basis of ^(79)Br NMR method.Finally,LiCl-KCl two-component molten salt(59.2 mol%LiCl-40.8 mol%KCl,eutectic melting point 353℃)was selected for HT-NMR experiment to verify the accuracy of temperature calibration,and check the performance of the HT-NMR method.[Results]Experimental results show that the sample cells are applicable in molten salt systems at a maximum temperature of 700℃,which meets the detection requirements of most molten salt systems.Additionally,the measurement results of the 79Br chemical shift of the KBr samples and captured HT 35Cl NMR spectra of the LiCl-KCl molten salt verify the reliability of the sample cell.[Conclusions]Based on the results,the HT-NMR(High Temperature NMR)sample cells proposed in this study can be widely applied in various fields when the molten salt system requirements are met.
作者
吴慧妍
应苏俊恒
刘一阳
黄海龙
葛敏
钱渊
付晓彬
刘洪涛
WU Huiyan;YINGSU Junheng;LIU Yiyang;HUANG Hailong;GE Min;QIAN Yuan;FU Xiaobin;LIU Hongtao(Key Laboratory of Interfacial Physics and Technology,Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《核技术》
CAS
CSCD
北大核心
2023年第3期111-118,共8页
Nuclear Techniques
基金
国家自然科学基金青年基金(No.22103094)
中国科学院上海应用物理研究所育新计划项目资助。
