Particle-In-Cell(PIC)simulations were performed in this work to study the dynamics of the EUVinduced hydrogen plasma.The Monte-Carlo Collision(MCC)model was employed to deal with the collisions between charged particl...Particle-In-Cell(PIC)simulations were performed in this work to study the dynamics of the EUVinduced hydrogen plasma.The Monte-Carlo Collision(MCC)model was employed to deal with the collisions between charged particles and background gas molecules.The dynamic evolution of the plasma sheath,as well as the flux and energy distribution of ions impacting on the mirror surface,was discussed.It was found that the emission of secondary electrons under the EUV irradiation on the ruthenium mirror coating creates a positively charged wall and then prevents the ions from impacting on the mirror and therefore changes the flux and energy distribution of ions reaching the mirror.Furthermore,gas pressure has a notable effect on the plasma sheath and the characteristics of the ions impinging on the mirrors.With greater gas pressure,the sheath potential decreases more rapidly.The flux of ions received by the mirror grows approximately linearly and at the same time the energy corresponding to the peak flux decreases slightly.However,the EUV source intensity barely changes the sheath potential,and its influence on the ion impact is mainly limited to the approximate linear increase in ion flux.展开更多
基金supported by National Natural Science Foundation of China(Nos.12172356,U23B20110)the Interdisciplinary and Collaborative Teams of CAS。
文摘Particle-In-Cell(PIC)simulations were performed in this work to study the dynamics of the EUVinduced hydrogen plasma.The Monte-Carlo Collision(MCC)model was employed to deal with the collisions between charged particles and background gas molecules.The dynamic evolution of the plasma sheath,as well as the flux and energy distribution of ions impacting on the mirror surface,was discussed.It was found that the emission of secondary electrons under the EUV irradiation on the ruthenium mirror coating creates a positively charged wall and then prevents the ions from impacting on the mirror and therefore changes the flux and energy distribution of ions reaching the mirror.Furthermore,gas pressure has a notable effect on the plasma sheath and the characteristics of the ions impinging on the mirrors.With greater gas pressure,the sheath potential decreases more rapidly.The flux of ions received by the mirror grows approximately linearly and at the same time the energy corresponding to the peak flux decreases slightly.However,the EUV source intensity barely changes the sheath potential,and its influence on the ion impact is mainly limited to the approximate linear increase in ion flux.
文摘新生儿，男，，因“发现骶部巨大包块并破溃0．5 d”入院。患儿出生后即发现腰骶部巨大包块并破溃，入院体检：生命体征稳定，对外界反应可，双侧瞳孔等大等圆，D ＝1．5 mm，对光反射灵敏。颈软，两肺呼吸音清，未闻及明显干湿性音；心尖搏动有力，律齐，各瓣膜听诊区未闻及明显病理性杂音。腹平软，肝脾未及，肠鸣音正常。骶部巨大包块，约20 cm ＆#215;20 cm，质地软，张力高，可见一大小约5 cm ＆#215;5 cm 的破溃，渗血，四肢活动可，各深浅反射存在，病理征未引出。治疗经过：血液分析示白血胞升高，血生化示高钾血症，肝肾功能基本正常，低蛋白血症。查 MRI 示尾部畸胎瘤可能性大。手术经过：①全麻成功后，患儿取左侧俯卧位，常规消毒铺巾。②在膨出处沿膨出物作一横棱形切口，在正常皮肤与变异皮肤交界处小心切开，分离皮下与肿物间隙，见肿物囊实性，多腔，囊液呈清亮淡黄色，未见毛发、骨骼等物。前面压迫直肠，后面压迫骶尾骨。③小心仔细剥离肿物并完整切除，保护肛周皮肤。骶尾部未见与椎管相通，无液体渗出，切除部分骶尾骨，骶间动脉严格止血。④清点器械无误，严格止血，修剪多余皮肤后分层缝合皮肤。术后病理：（骶尾部）不成熟性畸胎瘤，Ⅰ级。
