Linear accelerator : linear accelerator for medicine could generate x - ray with higher energy , which is currently the main radiotherapy equipment for malignant turmor . it has advantages such as high penetration ability , even fluid speed , minimum penumbra and could be used in treatment on tumors around whole body 由于直线加速器能够产生较高能量的x线,是目前治疗恶性肿瘤的主流放射设备,它具有穿透能力强,速流均整,半影极小等优点,适应证范围包括身体各部位的肿瘤。
Surface flashover across the insulators in vacuum is the major limitation of the performance of the high power system , such as high power microwave tube , pulse power switch , high - energy linear accelerator , etc . flashover studies are of considerable importance in many applications . alumina ceramics are used widely in vacuum insulation system . the flashover and charging performance have been systematically investigated on alumina ceramics in vacuum under pulse voltage ( 0 . 7 / 4 ^ 8 ) 真空中绝缘子沿面闪络现象是制约高功率微波管、脉冲功率开关、高能粒子加速器等系统性能的主要原因,这是因为真空中绝缘子在一个比自身及相同真空间隙击穿电场低得多的电场下就发生了表面闪络的缘故,研究真空中绝缘子沿面闪络现象及其形成机理对于改善和提高系统性能有重要意义。
Being high power resources of millimeter - wave radiation , based on electron cyclotron maser , gyrotron has been pay much respect in the world for vast applications in many areas such as plasma heating , linear accelerators , millimeter wave radar , communications , electronic countermeasure and so forth . specifically in twenty years later , there was much developments on gyrotron 回旋脉塞器件? ?回旋管作为大功率毫米波源,在等离子体加热、线性加速器、雷达、通信及电子对抗等领域有着广泛的应用前景,由此受到了国际上的高度重视,特别是近二十年来,回旋管得到了快速的发展,并成为研究的热门方向。
The present studies aimed to find the responses of neurons and glias in the target and other brain areas of the linear accelerator - irradiated rats . in the first experiment , time - dependent neurons changes in the brain after hemispheric irradiation at an single - fraction maximal dose of 20 gy were observed by investigating the expression of an immediate early gene , fos protein . the results shown : compared with that of the un - radiated rats , the expression of fos protein in the irradiated brain decreased distinctly 24 hours and 1 week after irradiation 首先,利用即刻早期基因fos的表达,做了同一照射剂量( 20gy )照射大鼠半脑后不同存活期间( 1d , 7d , 14d , 2ld , 28d )大鼠全脑神经元动态变化的观察,发现:受照射后1d 、 7d大鼠脑内各部位fos蛋白表达均明显减少,随着时间的延长,其fos免疫反应性细胞数量逐渐增加,照射后28d ,延髓、第四军医大学硕士学位论文脑桥内hs免疫阳性细胞数量恢复并超过正常对照组水平,但中脑、间脑及端脑内未恢复到正常对照组水平。
Bing high power resources of millimeter - wave radiation , based on electron cyclotron maser , gyrotron has been pay much respect in the world for vast applications in many areas such as plasama calefaction , linear accelerators , millimeter wave radar , communications , electronic countermeasure and so forth . prof . liu shenggang began the research on electron cyclotron maser , and later , the group leaded by prof . li hongfu has done much research work on gyrotron also , , and later , they have began the research on a kind of gyrotron amplifier - - - - - - gyroklystron 回旋脉塞器件? ?回旋管作为大功率毫米波源,在等离子体加热、线性加速器、雷达、通信及电子对抗等领域有着广泛的应用前景,因此受到了国际上的广泛重视,特别是近三十年来,回旋管得到了快速的发展,并成为了研究的热门方向。