【摘要】：目前,~3He已經(jīng)廣泛應(yīng)用于中高能核物理領(lǐng)域及生物醫(yī)學(xué)領(lǐng)域,特別是在肺部診斷中,基于超極化~3He氣體的磁共振成像可以提供清晰的肺部病灶圖像,為實(shí)現(xiàn)肺部疾病的早期診斷提供了可能。本論文主要基于堿金屬自旋交換光泵浦的原理,設(shè)計(jì)并制作出基于超極化~3He氣體的極化腔,并在自主設(shè)計(jì)的~3He極化裝置中實(shí)現(xiàn)純Rb和Rb-K兩類交換介質(zhì)下~3He的極化,并對(duì)極化后的超極化~3He氣體進(jìn)行提取和保存,使其應(yīng)用于低場(chǎng)磁共振的肺部成像。主要工作內(nèi)容和成果如下:首先,比較不同堿金屬與~3He間的自旋交換率和自旋弛豫率,并探索當(dāng)使用混合堿金屬作為交換介質(zhì)時(shí),不同堿金屬蒸汽在極化腔中的最佳蒸汽密度比D值;討論極化腔表面積與體積的比例對(duì)于~3He極化度的影響。其次,根據(jù)具體的實(shí)驗(yàn)要求,設(shè)計(jì)并搭建用于超極化~3He氣體的極化腔及其附屬支管,討論不同的材料在極化過(guò)程中對(duì)~3He氣體的影響,并對(duì)管路的制作流程進(jìn)行詳細(xì)闡述。再次,針對(duì)極化腔的制作進(jìn)行抽真空充氣系統(tǒng)的設(shè)計(jì)和搭建,對(duì)搭建的抽真空充氣管路進(jìn)行測(cè)試使其滿足設(shè)計(jì)需求,并在此基礎(chǔ)上總結(jié)相應(yīng)實(shí)驗(yàn)氣體的充氣測(cè)量的方法。此外,設(shè)計(jì)并搭建基于超極化~3He氣體的提取裝置,比較不同材料對(duì)超極化~3He氣體退極化率的影響,并制作出儲(chǔ)存極化氣體的采樣袋。最后,利用搭建完成的極化腔和抽真空充氣系統(tǒng)以及配置好的堿金屬混合物制作出基于超極化~3He氣體的極化腔,并使用電子順磁共振方法(EPR)對(duì)極化腔中的超極化~3He氣體的極化度進(jìn)行測(cè)量,得到輸運(yùn)曲線和自旋弛豫曲線。
[Abstract]:At present, ~ 3He has been widely used in the field of middle and high energy nuclear physics and biomedicine, especially in the diagnosis of lung. Magnetic resonance imaging based on hyperpolarizing ~ 3He gas can provide clear images of lung lesions. It provides the possibility for early diagnosis of lung diseases. Based on the principle of alkali metal spin-exchange optical pump, a polarizing cavity based on hyperpolarization ~ 3He gas is designed and fabricated in this paper. The polarization of ~ 3He is realized in the self-designed ~ 3He polarizing device under two kinds of switching media, pure Rb and Rb-K. The hyperpolarized ~ 3He gas was extracted and preserved for low field magnetic resonance imaging. The main contents and results are as follows: firstly, the spin exchange rate and spin relaxation rate between different alkali metals and ~ 3He are compared, and when mixed alkali metals are used as exchange medium, The optimum vapor density ratio D of different alkali metal vapor in polarized cavity; The effect of the ratio of surface area to volume of polarized cavity on the polarizability of ~ 3He is discussed. Secondly, according to the specific experimental requirements, the polarization cavity for hyperpolarized ~ 3He gas and its subsidiary branch tubes are designed and built. The effects of different materials on the ~ 3He gas during the polarization process are discussed, and the fabrication process of the pipeline is described in detail. Thirdly, the vacuum inflatable system is designed and built for the fabrication of the polarized cavity, and the vacuum inflatable pipeline is tested to meet the design requirements. Based on this, the method of gas inflatable measurement for the corresponding experimental gas is summarized. In addition, an extraction device based on hyperpolarization ~ 3He gas was designed and built to compare the effects of different materials on the depolarizability of hyperpolarized ~ 3He gas, and a sample bag was made to store the polarized gas. Finally, the polarizing cavity based on hyperpolarization-3He gas is fabricated by using the completed polarization cavity, vacuum inflatable system and the configured alkali metal mixture. The electron paramagnetic resonance (EPR) method is used to measure the polarizability of the hyperpolarized ~ 3He gas in the polarized cavity. The transport curves and spin relaxation curves are obtained.
【學(xué)位授予單位】：合肥工業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：R563

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 張曉;楊瓊英;林國(guó)楨;沈紀(jì)川;周琴;李科;董航;宋韶芳;劉北燕;陳清;;大氣污染與居民肺癌發(fā)病及死亡灰色關(guān)聯(lián)分析[J];中國(guó)公共衛(wèi)生;2014年02期

2 陳仁杰;張金良;闞海東;;中國(guó)大氣污染與肺癌關(guān)系的流行病學(xué)研究回顧[J];衛(wèi)生研究;2011年02期

，

本文編號(hào)：2357100