扫描力显微镜图象中离子潜径迹的表现形式

用扫描力显微镜（ＳＦＭ）观测高能重离子轰击云母样品造成朱零星戏迹在不同的ＳＦＭ图象中的表现形式，并探讨了针尖在表面扫描时摩擦力对ＳＦＭ图象中离子潜径迹反差的影响。     

快重离子在石墨中引起表面及体径迹的STM研究

用多种快重离子辐照高定向石墨（HOPG），借助扫描隧道显微镜（STM）系统地研究了表面及体内缺陷，结果表明，离子在表面及解理面上都形成了小丘状的缺陷，且在表面较容易形成，可以用非连续损伤径迹结构来对其进行解释。     

电子能损引起的潜径迹

潜径迹是电子能损在凝聚态物质中引起重要效应之一,给出了一个关于引起潜径迹电子能损阈值,损伤截面以及径迹形貌的综合评述。     

荷电离子轰击靶材料损伤潜径迹的原子水平观测研究

叙述了用扫描隧道显微镜和原子力显微镜观测研究荷电离子轰击靶材料的损伤潜径迹的状况和进展，观测研究了Ａｕ离子和Ｈ＾＋轰击高定向石墨的ＳＴＭ。给出了损伤形貌、损伤范围、表面损伤数密度和离子注入剂量的关系，并对损伤过程进行了分析和讨论。     

快重离子在聚合物潜径迹中引起的损伤效应研究

在室温和真空环境下利用不同的快重离子(1.158GeV Fe56、1.755GeV Xe136及2.636GeV U238)对多层堆叠的聚对苯二甲酸乙二醇酯(PET)、聚碳酸脂(PC)和聚酰亚胺(PI)进行了辐照,结合X射线衍射(XRD)、傅立叶红外光谱(FTIR)及紫外可见光谱测量技术,在较宽的电子能损(1.9-19.0 keV·nm-1)和注量范围(1×1010-6×1012 cm-2)研究了离子在不同聚合物潜径迹中引起的损伤过程,观测到了主要官能团的降解、炔基生成、非晶化及紫外吸收边缘的红移等现象随辐照注量及电子能损的变化趋势.通过对损伤过程的定量分析,应用径迹饱和模型假设,分别给出了Fe、Xe和U离子在不同电子能损下辐照PC时的平均非晶化径迹半径和炔基形成半径,并用热峰模型对实验结果进行了检验.     

CR-39固体核径迹探测器观测方法

针对重离子辐射的CR - 39固体核径迹探测器中的微观径迹结构特点和剂量特征研究的必要步骤——探测器观测,从CR - 39中粒子潜径迹形成和发展出发,探讨了影响粒子径迹的因素,选取两种径迹观测方法——光学显微镜观测和电子显微镜观测进行对比分析.在此基础上进行了试验,用不同通量的100 MeV Si离子照射CR - 39...     

纳米尺度上CR-39径迹蚀刻动力学研究

在对CR-39探测器蚀刻6h后发现照射区域与未照射区域的体蚀刻速率明显不同,因此用传统的几何模型无法正确得到几何量和物理量之间的对应联系.本文在以往辐射粒子固体径迹研究基础上,利用新的AFM观测手段得到纳米尺度的CR-39三维蚀刻径迹坑,并对探测器蚀刻几何模型进行了修正,提出了新的蚀刻速率比:V′＝V′/Virr对几何...     

电子能损的潜径迹形成机制及理论模型的新进展

潜径迹是荷能离子与固体相互作用的一个重要效应，可以借助化学蚀刻，电子显微镜，卢瑟福散射和其他方法所显同，通过研究依赖于离子能量和各种靶参数的径迹尺寸的变化可以获得关于微观机制的信息，本文概括地介绍了在电子能损体制下径迹形成的基本现象，观测技术以及所获得的重要的实验结果，评价了描述径迹形成机制的理论模型和最新进展。     

碳微集团束的产生及其在CR-39中径迹的AFM观测

在HI－13串行加速器上实现了对碳微集团的加速，得到了MeV级的碳微集团束，对产生的碳的微集团束进行了测量并用它对CR＝－39塑料核径迹探测器进行了辐照，利用先进的原子力显微镜对C1和C2在CR－39中的径迹进行了观测。     

质子、α粒子在水蒸气中径迹结构的研究

本工作采用模拟粒子在水蒸气中输运的蒙特卡罗程序,模拟计算了0.3～5MeV质子、α粒子在水蒸气中的径迹结构,记录了相互作用位置的坐标、每次事件中的能量沉积以及相互作用的类型。程序中考虑了弹性散射、电离、激发、电荷转移等物理过程。研究得到了一些有益的结果,为进一步研究粒子致DNA辐射损伤的物理模型奠定了一定的基础。     

Effect of Gamma Irradiation on Celluloid Film and Related Influence on the Registration of Alpha Tracks

Celluloid film, used as for α-track detection for its being one of the most sensitive solid state track detectors, was irradiated up to 3.5 × 10⁷ rad by ⁶⁰Co γ-rays. The radiation damage was examined by weighing a piece of the film before and after etching with sodium hydroxide solution under various conditions. Six molar sodium hydroxide solution at 50°C was found to be the most suitable etching solution for this irradiated celluloid film. On measuring the optical density, it was seen that the absorption curve for UV light shifted to the longer wavelength side accompanying an increase of absorption dose of γ-ray energy on the film. Both the gravimetric and the optical methods of determining radiation damage indicated its dependence on the γ-ray absorption dose. The sensitivity of α-track registration was also estimated by examining the appearance of α-track under the optical microscope according to etching time. The critical energy of the celluloid film for the registration of α-tracks decreased with the absorption dose of γ-rays.     

Characterization of swift heavy ion tracks in CaF2 by scanning force and transmission electron microscopy

Single crystals of fluorite (CaF₂) were exposed to various swift heavy ions (Ca up to U) of energy 1–11.1 MeV per nucleon, covering a large range of electronic stopping power S_e between 4.6 and 35.5 keV/nm. The irradiated (1 1 1) cleaved surfaces were investigated by means of scanning force microscopy in tapping mode. Nanometric hillocks produced by the ion projectiles were analyzed in terms of creation efficiency E_eff, diameter and height values, and diameter–height correlation. Hillock formation appears with a low efficiency above a S_e threshold of 5 keV/nm. The mean height of these hillocks is approximately constant (1 nm) between 5 and 10 keV/nm and increases linearly with S_e above 10 keV/nm reaching 12.5 nm for the largest S_e value investigated. Similarly, the efficiency grows versus S_e achieving 100% for S_e > 13 keV/nm where each projectile produces an individual hillock. Above 13 keV/nm, the hillock height and diameter are strongly correlated. The diameter was deduced by graphical deconvolution of the scanning-tip curvature that is determined experimentally for each set of measurements. In the entire S_e regime, the mean diameter exhibits a constant value of 13 nm, which is significantly larger than 6 nm wide tracks observed by transmission electron microscopy.     

用正电子湮没技术研究新锆合金包壳的离子辐照效应

国产Zr-Sn-Nb系新锆合金SZA-4和SZA-6是CAP1400大型先进压水堆包壳材料的主要候选材料,对其辐照性能的研究可为制备工艺改进提供科学依据。在中国原子能科学研究院HI-13串列加速器辐照终端,在300 ℃温度下,用100 MeV的Fe束流对两种新锆合金包壳管材进行5 dpa剂量辐照。辐照前后的正电子湮没寿命测量表明：两种样品辐照前湮没寿命为Zr中单空位寿命,表明管材制备过程中最后的退火温度和时间尚未完全消除加工引入的缺陷;两种样品辐照后的正电子湮没寿命减小,分析表明这是由于辐照导致Fe在锆合金中重新分布,主要分布在bcc结构的β-Nb沉淀相颗粒与hcp结构的α-Zr基体之间具有开空间的相界,正电子被相界捕获,与周围Fe原子电子湮没,造成湮没寿命减小。     

Radiation Blistering of Vanadium Irradiated with 40keV 4He Ions

The vapor pressure of strontium in the temperature range of 494~660°K has been determined by the mass spectrometric Knudsen effusion method. The temperature dependence of the vapor pressure in Pa is given by the equation: log 10.750 ± 0.122 - (8,427±69)/T. From the values of vapor pressure, heats of vaporization of strontium were obtained to be ΔH° _u298= 163.8 ±1.6 kJ/mol by the second law treatment and ΔH°_u298 = 161.9 ±0.5 kJ/mol by the third law treatment.     

大规模集成电路抗辐射性能无损筛选方法研究

结合数学回归分析与物理应力实验的方法,研究了集成电路抗辐射性能无损筛选技术。通过一定的外界能量注入及总剂量辐照实验,探究电路典型参数的应变情况与电路耐辐射性能的关系,并确定其辐射敏感参数;建立预测集成电路抗辐射性能的多元线性回归方程,并对应力条件下的回归方程进行辐照实验验证。结果显示,数学回归分析与物理应力实验结合的方法提高了无损筛选的可靠性。     

Observation of atomic steps on CaCO3 crystal surface

By using scanning polarization force microscopy,the deliquescence process and the atomic steps on the cleavage surface of CaCO3 in air were studied in situ.Under an exposure to medium umidity(-57%),the sloiw step movement has been observed.     

基于动力学标度法的a-C:H薄膜表面微观形貌的演变机理研究

采用等离子体增强化学气相沉积(PECVD)方法在Si(111)基底上制备a-C:H薄膜,利用原子力显微镜(AFM)和扫描电子显微镜(SEM)对a-C:H薄膜的表面形貌与表面粗糙度进行表征,并从动力学标度法角度出发讨论a-C:H薄膜表面粗糙度的演变机理。研究结果表明:a-C:H薄膜表面微观形貌为自仿射分形表面,可用分形维数来评价薄膜的表面粗糙度;随着H_2流量的增加,薄膜表面粗糙度先减小后增大,在T_2B与H_2流量比为0.2/6时,a-C:H薄膜的表面粗糙度R_q为2.2nm,相对于其他条件下生长的薄膜的表面粗糙度低,薄膜表面较光滑,致密性良好。     

Radiation Damage Study on Various Structural Refractory Alloys of a Multi-Purpose Reactor

Radiation damage properties of structural materials play a key role in design of a fusion–fission (hybrid) reactor. Refractory alloys offer a significant advantage of high neutron wall load capability under fusion neutron environment. In this study, main radiation damage parameters (displacement per atom (DPA) and helium production) on three different refractory alloys, namely W-5Re, TZM (Mo alloy) and Nb–1Zr used as structural material in a hybrid reactor were found. Neutron transport calculations were conducted with the aid of SCALE4.3 System by solving the Boltzmann transport equation with code XSDRNPM. The lowest radiation damage values were obtained for W-5Re alloy. Moreover, all investigated materials will require to be replaced frequently due to their radiation damage values during reactor life (~ 30 years).     

BEGe探测器晶体参数的蒙特卡罗计算与实验表征技术研究

利用²⁴¹Am发射的59.54 keV平行γ射线束对宽能BEGe探测器晶体进行扫描测量,通过晶体端面垂直扫描确定晶体直径,通过晶体侧面垂直扫描确定晶体高度。利用厂家提供的参数以及扫描得到的晶体参数建立蒙特卡罗计算模型,再通过点源和体源的实验测量值对晶体前端面及侧面死层厚度进行表征调节,使其与实验值符合,从而获得最佳理论计算模型。结果表明,获得的参数正确可靠,其点源探测效率的理论计算结果与实验测量值在2%内符合。该方法极大改善了蒙特卡罗计算BEGe晶体探测效率的精度,可应用于探测器的效率刻度及环境放射性调查。     

Observation of Central Toroidal Rotation Induced by ICRF on EAST

Core plasma rotation of both L-mode and H-mode discharges with ion cyclotron range of frequency(ICRF) minority heating(MH) scheme was measured with a tangential X-ray imaging crystal spectrometer on EAST(Experimental Advanced Superconducting Tokamak).Cocurrent central impurity toroidal rotation change was observed in ICRF-heated L-and H-mode plasmas.Rotation increment as high as 30 km/s was generated at ~1.7 MW ICRF power.Scaling results showed similar trend as the Rice scaling but with significant scattering,especially in L-mode plasmas.We varied the plasma current,toroidal field and magnetic configuration individually to study their effect on L-mode plasma rotation,while keeping the other major plasma parameters and heating unchanged during the scanning.It was found that larger plasma current could induce plasma rotation more efficiently.A scan of the toroidal magnetic field indicated that the largest rotation was obtained for on-axis ICRF heating.A comparison between lower-single-null(LSN)and double-null(DN) configurations showed that LSN discharges rendered a larger rotation change for the same power input and plasma parameters.