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磁共振成像(MRI),利用非放射性和非侵入性手段,提供生物样品的空间结构和功能信息,成为临床诊断和生物医学研究的重要工具。然而,常规MRI通常使用生物体内高浓度氢核信号来成像,在常温1.0T磁场中1H极化度仅约为7×10-7,信号非常微弱,灵敏度相对较低,分辨率较差,如何提高核磁共振(NMR)的灵敏度和分辨率是一直以来的研究方向。由于极化率与主磁场B0强度成正比,磁场强度
Magnetic resonance imaging (MRI), using non-radioactive and non-invasive means to provide spatial structure and functional information of biological samples, has become an important tool for clinical diagnosis and biomedical research. However, conventional MRI usually uses high-concentration proton signals in vivo for imaging. The 1H polarization degree is only about 7 × 10-7 at a magnetic field of 1.0T at room temperature. The signals are very weak, the sensitivity is relatively low, and the resolution is poor. How Increasing the sensitivity and resolution of nuclear magnetic resonance (NMR) has long been the research direction. Since the polarization rate is proportional to the strength of the main magnetic field B0, the magnetic field strength