脉冲动态核极化增强的NMR 和MRI 系统研究
收稿日期: 2014-03-10
修回日期: 2015-05-08
网络出版日期: 2015-06-05
基金资助
Grant from the special equipment of scientific instrument of Chinese Academy of Sciences, the Ministry of Science and Technology of China (2011YQ120035) and the National Natural Science Foundation of China (11405264).
Development of Pulsed Dynamic Nuclear Polarization for Enhancing NMR and MRI
Received date: 2014-03-10
Revised date: 2015-05-08
Online published: 2015-06-05
Supported by
Grant from the special equipment of scientific instrument of Chinese Academy of Sciences, the Ministry of Science and Technology of China (2011YQ120035) and the National Natural Science Foundation of China (11405264).
该文介绍了一种自行设计和构建的可扩展脉冲动态核极化谱仪，可以实现核磁共振波谱与磁共振成像的功能．该仪器的新颖设计主要有：1) 采用基于PCIe 的分布式总线结构，能够极大地提高数据传输效率和通信可靠性，实现精确控制脉冲序列；2) 采用外部高速的DDR 芯片存储脉冲序列元素和FID 数据，可以极大的提高脉冲序列的执行速度，减少快速成像序列的TR 时间间隔；3) 采用时钟移相技术，可以精确产生分辨率为纳秒级别的数字脉冲．最后对该仪器的动态核极化-磁共振波谱与核磁共振成像功能进行了实验验证．
关键词： 核磁共振(NMR); 磁共振成像(MRI); 脉冲动态核极化; 控制台; PCIe
贺玉贵1 , 2 , 冯继文1* , 张志1 , 3 , 王超1 , 3 , 倪胜1 , 胡少斌1 , 王东1 , 陈方1 , 刘买利1 , 刘朝阳1* . 脉冲动态核极化增强的NMR 和MRI 系统研究[J]. 波谱学杂志, 2015 , 32(2) : 393 -398 . DOI: 10.11938/cjmr20150221
In this report, we present a pulsed dynamic nuclear polarization (DNP) system, being reconfigurable for DNP enhanced magnetic resonance imaging (DNP-MRI) and magnetic resonance spectroscopy (DNP-MRS). Several novel console designs are proposed in the presented DNP system. A distributed digital architecture based on Peripheral Component Interconnect Express (PCIe) has been developed, so as to significantly improve the efficiency of data transmission and communication reliability as well as the precise control of pulse sequence. An external high speed Double Data Rate (DDR) memory chip is used for storing FID data and pulse sequence elements, greatly speeding up the execution of the pulse sequence and reducing the interval of TR and improving the accuracy of TR in image sequence. Using clock phase-shift technology, we can produce digital pulse accurately with high timing resolution of nanosecond timescales. Finally, two experimental examples for DNP-MRS and DNP-MRI are shown.
Key words： NMR; MRI; pulsed DNP; console; PCIe
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