Comparison of helium bubble formation in F82H,ODS, SIMP and T91 steels irradiated by Fe and He ions simultaneously

Ferritic-martensitic steels and ODS steels are attractive candidates for structural materials in advanced nuclear-power systems due to their good swelling resistance. Four kinds of steels, F82 H, 15 Cr-ODS, SIMP and T91, are investigated in this study. We take 6.4 Me V Fe3+ ions and energy-degraded 1.0 Me V He+ ions in the irradiation of these materials to 5 dpa and 60 appm He/dpa, 200 appm He/dpa and 600 appm He/dpa at 300℃ and 450℃, respectively. The bubble formation and distribution are investigated by transmission electron microscopy(TEM). Formation and distribution of the bubbles in the four investigated steels are compared. The influence of irradiation temperature and helium injection ratio on bubble formation is discussed. It is found that there appears to be homogenously distributed bubbles at 300℃ irradiation while heterogeneously distributed bubbles at 450℃ irradiation.     

注氦尖晶石的红外光谱研究

利用傅立叶变换红外光谱仪对注He尖晶石样品随退火温变化而引起光吸收性能的变化进行了研究。 发现尖晶石样品在626.4 cm-1附近的吸收峰随注入剂量的增加向小波数方向移动, 而在随后退火过程该吸收峰随退火温度的增加而向大波数方向回复。 该吸收峰的回复行为依赖于注入剂量和退火温度。 认为在626.4 cm-1附近吸收峰随注入剂量和退火温度的这种变化与尖晶石中He的俘获以及释放有关。 The infrared absorption behavior of helium implanted spinel with annealing temperature was studied by Fourier transformed infrared (FTIR) spectroscopy. It was found that the absorbance peak at 626.4 cm-1 shifted to smaller wave numbers with the increase of implantation fluence, while on subsequent annealing the absorbance peak shifted back to larger wave numbers with the increase of annealing temperature. The shift of the peak at 626.4 cm-1 with He implantation/annealing is considered to be related with the trapping and release of helium atoms in lattice sites in the spinel crystal.     

He注入单晶Si表面形貌的变化研究

沿Si的（100）面注入He离子, 能量为30 keV、 剂量为5×1016 ions/cm2。 注入后样品切成几块, 在真空炉中分别做退火处理, 退火温度从600 ℃到1 000 ℃, 退火时间均为30 min。 利用原子力显微镜研究了各个样品表面形貌的演化。 发现样品表面形貌与退火温度相关联。 假设在气泡中He原子与空位的比值很高, 导致样品内部存在高压的He泡, 从而使样品表面形貌发生变化。 探讨了在Si中He泡随退火温度的演化和He原子在材料中的释放机制及其对表面的影响。     

He离子注入的尖晶石中Au纳米颗粒的合成研究

利用20 keV的He离子注入表面蒸镀了Au薄膜的尖晶石（MgAl2O4）样品, 随后对注入样品进行了退火处理。 在紫外可见光谱上观察到了由于金属纳米颗粒的存在而引起的较强的表面等离子体共振吸收峰, 提供了材料中金属纳米颗粒形成的光谱证据。 并对形成的Au纳米颗粒的尺寸随退火温度以及He注入剂量的变化进行了研究。 Spinel deposited with a thin Au film was implanted with helium ions, and annealed in vacuum condition subsequently. The surface Plasmon resonance absorbance peak due to the existence of metallic nanoparticles in the dielectric matrix was observed on the Ultraviolet Visible Spectrometry, indicating the formation of metallic nanoparticles in spinel. The dependence of Au particles size with annealing temperature and implantation doses was also investigated.     

高电荷态离子$lt;sup$gt;126$lt;/sup$gt;Xe$lt;sup$gt;$lt;i$gt;q$lt;/i$gt;+$lt;/sup$gt;引起GaN表面形貌变化研究

用不同电荷态的¹²⁶Xe^q+离子（9≤q≤30）在室温下轰击GaN晶体表面,经原子力显微镜分析表明,当q>18,辐照区域由隆起转为显著的刻蚀.被轰击后的GaN晶体表面形貌主要取决于入射离子的电荷态.同时,样品表面形貌还与入射离子的剂量和入射角有关;在实验参数范围,与入射离子的初动能没有明显关系（180 keV≤E_k≤600 keV）.当入射离子的电荷态q=18,与样品表面法线成60°角倾斜入射和垂直表面入射时,样品的表面几乎没有变化,只是倾斜入射后有很微小的隆起;当q＜18时,样品表面膨胀隆起,粗糙度增强,倾斜入射时表面隆起比垂直入射时更明显,而且都有清晰的峰状分界区;当q＞18时,样品表面被蚀刻呈凹陷状,有明显的齿状刻痕,且侵蚀深度与离子剂量近似呈线性关系,倾斜入射时的刻蚀深度大于垂直入射时的刻蚀深度. 关键词： 高电荷态离子 GaN晶体 原子力显微镜 表面形貌     

Surface Disorder of GaN Irradiated by Highly Charged Arq+-Ions

The surface damage to gallium nitride films irradiated by Ar^q＋ （6≤q≤16） ions at room temperature is studied by the atomic force microscopy. It is found that when charge state exceeds a threshold value, significant swelling was turned into obvious erosion in the irradiated region. The surface change of the irradiated region strongly depends on the charge state and ion fluence. On the other hand, surface change is less dependent on the kinetic energy nearly in the present experimental range （120 keV≤Ek≤220 keV）. For q≤14, surface of the irradiated region is covered with an amorphous layer, rough and bulgy. A step-up appears between the irradiated and un-irradiated region. Moreover, the step height and the surface roughness are functions of the ion dose and charge state, and increase with the increase of dose and charge state. Especially at and near boundary, a sharp bump like ridges in irradiated areas is observed, and there appear characteristic grooves in un-irradiated areas. For q=16, surface of the irradiated region was etched and erased.     

SFC新引出系统的物理设计研究

兰州重离子加速器(HIRFL)是一个回旋加速器组合系统. 它的注入器是K=69的扇聚焦回旋加速器.在十多年运行过程中, 曾做过两次较大的改进, 使加速的束流种类及流强都有了显著的改善.但由于SFC的引出效率比较低, 只有30%左右, 一方面损失了大量束流, 另一方面许多束流损失在引出静电偏转板上, 造成了大量出气, 破坏了真空, 难以维持长期大束流运行. 文章重新对SFC引出系统进行了物理设计研究, 在真实磁场的基础上做了大量计算工作, 得到了一个新的引出 系统方案.     

健心Ⅰ号对阿霉素培养心肌细胞过氧化脂质生成与LDH的影响

1 引言阿霉素是一种有效的抗肿瘤药物,但对心肌细胞有严重损伤。一般认为阿霉素能引起数种复杂的生化变化。但近年来有文献报道,阿霉素引起的心脏毒性的主要途径可能是通过自由基反应,而导致膜脂质过氧化物的反应。前文已证明健心Ⅰ号具有清除自由基的能力和抑制脂质过氧化的生成作用,本文进一步观察了健心Ⅰ号对阿霉素所致的培养心肌细胞内过氧化脂质生成丙二醛(MDA)以及心肌酶——乳酸脱氢酶(LDH)释放的影响。     

He离子辐照6H-SiC引入缺陷的光谱研究

实验采用300 keV的He²⁺辐照6H-SiC,辐照温度分别为室温,450,600和750 ℃,辐照剂量范围为1×10¹⁵–1×10¹⁷ cm^-2,辐照完成后对样品进行拉曼散射和紫外可见透射光谱测试与研究. 这两种分析方法的实验结果表明,He离子辐照产生的缺陷以及缺陷的恢复与辐照剂量和辐照温度有着直接关系. 室温下辐照会使晶体出现非晶化,体现在拉曼特征峰消失,相对拉曼强度达到饱和(同时出现了较强的Si-Si峰);高温下辐照伴随着晶体缺陷的恢复过程,当氦泡未存在时,高温辐照很容易导致Frenkel对、缺陷团簇等缺陷恢复,当氦泡存在时,氦泡会抑制缺陷恢复,体现在相对拉曼强度和相对吸收系数曲线斜率的变化趋势上. 本文重点讨论了高温辐照情况下氦泡对缺陷聚集与恢复的影响,并与高温下硅离子辐照碳化硅结果进行了对比. 关键词： 6H-SiC 氦泡 拉曼散射光谱 紫外可见透射光谱     

抗癌药新剂型-白蛋白微球剂

白蛋白微球剂是一种新的药物剂型。本文概述了微球剂的制备方法及操作条件对作用机理及体内分布的影响,白蛋白微球剂是用人(或牛)血清、药物、附加剂的混合物,注入表面活性剂及注射用棉子油经超声波乳化,再经热或交联剂固化而成,其功能和性质与制备过程中的各种条件如与搅拌速度,乳化剂的用量,固化方式及温度等有关.作用机理主要通过内吞和融合作用,在体内主要分布于肝脏.较其他剂型具有多方面的优越性。