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Helium-Implantation-Induced Damage in NHS Steel Investigated by Slow-Positron Annihilation Spectroscopy

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Chinese Physics Letters 2014年第3期31卷 111-114页

作者： LI Yuan-Fei SHEN Tie-Long GAO Xing GAO Ning yao cun-feng SUN Jian-Rong WEI Kong-Fang LI Bing-Sheng ZHANG Peng CAO Xing-Zhong ZHU Ya-Bin PANG Li-Long CUI Ming-Huan CHANG Hai-Long WANG Ji ZHU Hui-Ping WANG Dong SONG Peng SHENG Yan-Bin ZHANG Hong-Peng HU Bi-Tao WANG Zhi-Guang Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 University of Chinese Academy of Sciences Beijing 100049 School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049

Evolutions of defects and helium contained defects produced by atomic displacement and helium deposition with helium implantation at different temperatures in novel high silicon （NHS） steel are investigated by a slow positron beam. Differences of the defect information among samples implanted by helium to a fluence of 1×1017 ions/cm2 at room temperature, 300°C, 450°C and 750°C are discussed. It is found that the mobility of vacancies and vacancy clusters, a recombination of vacancy-type defects and the formation of the He-V complex lead to the occurrence of these differences. At high temperature irradiations, a change of the diffusion mechanism of He atoms/He bubbles might be one of the reasons for the change of the S-parameter.

关键词： Positron annihilation spectroscopy

Cavity Swelling in Three Ferritic-Martensitic Steels Irradiated by 196 MeV Kr Ions

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Chinese Physics Letters 2013年第12期30卷 83-86页

作者： LI Yuan-Fei SHEN Tie-Long GAO Xing yao cun-feng WEI Kong-Fang SUN Jian-Rong LI Bing-Sheng ZHU Ya-Bin PANG Li-Long CUI Ming-Huan CHANG Hai-Long WANG Ji ZHU Hui-Ping HU Bi-Tao WANG Zhi-Guang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000 University of Chinese Academy of Sciences Beijing 100049 School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000

We report on cavity swelling at peak damage regions of three ferritic-martensitic(FM)steels(NHS,RAFM and T91)irradiated by 196 MeV Kr ions at different temperatures(450/550℃).Cavity configurations of the irradiated specimens are investigated by transmission electron microscopy with cross-section *** home-made reduced activation ferritic-martensitic(RAFM)and T91 steels irradiated at 450℃,both large size and bimodal size distribution of the cavity are found in their peak damage regions,whereas novel high silicon(NHS)steel exhibits good swelling resistance at different irradiation *** relativity of the cavity swelling in NHS,RAFM and T91 steels is discussed briefly.

关键词： martensitic ferritic steel

低速高电荷态重离子在C_(60)薄膜中引起的势效应研究

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原子核物理评论 2010年第2期27卷 223-227页

作者：付云翀姚存峰金运范中国科学院近代物理研究所甘肃兰州730000 中国科学院研究生院北京100049 中国科学院地球环境研究所西安710075

为了研究低速高电荷态离子在C60薄膜中引起的势效应,用能量为200keV的高电荷态Xen+(n=3,10,13,15,17,20,22,23)离子辐照了C60薄膜。用原子力显微镜(AFM)和Raman散射技术分析了辐照过程中高电荷态Xen+离子所储存势能在C60薄膜中引起的效... 详细信息

为了研究低速高电荷态离子在C60薄膜中引起的势效应,用能量为200keV的高电荷态Xen+(n=3,10,13,15,17,20,22,23)离子辐照了C60薄膜。用原子力显微镜(AFM)和Raman散射技术分析了辐照过程中高电荷态Xen+离子所储存势能在C60薄膜中引起的效应,即势效应。AFM分析结果表明,辐照C60薄膜的表面粗糙度随辐照Xen+离子电荷态(即势能)的增加而减小,揭示了势效应的存在。而Raman分析结果表明,由于Xe离子的动能远大于其所储存的势能,因此,尽管有表面势效应的影响,但在Raman分析的深度范围内,弹性碰撞还是主导了C60薄膜的损伤过程。

关键词：低速高电荷态离子 C60薄膜势效应

高温注氦及随后230MeV的^(208)Pb^(27+)辐照Al_2O_3的光致发光谱的研究

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高能物理与核物理 2005年第11期29卷 1112-1114页

作者：宋银张崇宏王志光赵志明段敬来姚存峰中国科学院近代物理研究所兰州730000

主要研究了110keV的He^+高温注入Al_2O_3单晶及1.1MeV/u的^(208)Pb^(27+)辐照注氦Al_2O_3样品的光致发光的特性。从测试结果可以清楚地看到在375nm,413nm和450nm处出现了强烈的发光峰。并且在600K,5×10^(16) ions/cm^2剂量点,样品的发光峰是最强的。这表明He^+注入Al_2O_3后使带隙中深的辐射中心复合的效率大幅度提高,极大的增强了其发光强度,而且发光伴随着蓝移现象。而经过高能^(208)Pb^(27+)辐照后的样品,在390nm出现了新的发光峰,从FTIR谱中我们能够看到,可能是^(208)Pb^(27+)辐照相对沉积膜出现一定的晶化,其中含有许多纳米尺寸的Al_2O_3晶粒所致。

关键词：离子注入重离子辐照 Al2O3 光致发光谱 FTIR谱辐照高温氦发光峰发光强度

Posttraumatic stress symptoms among Chinese university students during the COVID-19 pandemic:Prevalence,correlates,and mental health help-seeking

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World Journal of Psychiatry 2025年第1期15卷 145-152页

作者： Rui-yao Wu Lin-feng Ge Bao-Liang Zhong Department of Psychiatry The Affiliated Wuhan Mental Health CenterTongji Medical College of Huazhong University of Science&TechnologyWuhan 430012Hubei ProvinceChina Department of Psychiatry Wuhan Mental Health CenterWuhan 430012Hubei ProvinceChina

BACKGROUND Revisiting the epidemiology of posttraumatic stress symptoms(PTSSs)among university students during the coronavirus disease 2019(COVID-19)pandemic as well as understanding the mental health help-seeking behavior of individuals with PTSSs has critical implications for public mental health strategies in future medical *** To investigate the prevalence and correlates of PTSSs among university students during the first wave of the COVID-19 pandemic in China and to examine mental health help-seeking behaviors among these *** A total of 2507 Chinese university students were recruited via snowball *** students completed the Seven-item Screening Scale for Post-traumatic Stress Disorder during the first wave of the COVID-19 pandemic in ***-graphic characteristics,pandemic-related characteristics,and mental health help-seeking behaviors of students with PTSSs were also *** The prevalence of PTSSs among the participants was 28.0%.Seven significant correlates of PTSSs were identified(odds ratio=1.23-3.65,P≤0.024):Female sex,being 19 years old or older,living with others or alone,a low level of family economic status,fair or poor interpersonal relationships,severe or very severe local pandemic,and having family members diagnosed with ***,only 3.28%of the students with PTSSs reported seeking help from mental health *** the 23 students who sought help from mental health specialists,13 opted for online or telephone-based psychological *** Our data suggest that there was a high risk of PTSSs among university students and a high level of unmet mental health needs during the COVID-19 *** delivery of mental health services online or via telephone is a promising approach to address these unmet needs.

关键词： Posttraumatic stress symptoms University students COVID-19 Mental health help-seeking China

高电荷态离子^(126)Xe^(q+)引起GaN表面形貌变化研究

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物理学报 2009年第8期58卷 5578-5584页

作者：张丽卿张崇宏杨义涛姚存峰孙友梅李炳生赵志明宋书建中国科学院近代物理研究所兰州730000

用不同电荷态的126Xeq+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... 详细信息

用不同电荷态的126Xeq+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(180keV≤Ek≤600keV).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q18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

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离子注入ZnO薄膜的拉曼光谱研究

物理学报 2010年第7期59卷 4831-4836页

作者：臧航王志光庞立龙魏孔芳姚存峰申铁龙孙建荣马艺准缑洁盛彦斌朱亚滨中国科学院近代物理研究所兰州730000 中国科学院研究生院北京100049

室温下,用80keVN+和400keVXe+离子注入ZnO薄膜,注入剂量分别为5.0×1014—1.0×1017/cm2和2.0×1014—5.0×1015/cm2.利用拉曼散射技术对注入前后的ZnO薄膜进行光谱测量和分析,研究了样品的拉曼光谱随离子注入剂量的变化规律.实验结果发... 详细信息

室温下,用80keVN+和400keVXe+离子注入ZnO薄膜,注入剂量分别为5.0×1014—1.0×1017/cm2和2.0×1014—5.0×1015/cm2.利用拉曼散射技术对注入前后的ZnO薄膜进行光谱测量和分析,研究了样品的拉曼光谱随离子注入剂量的变化规律.实验结果发现,未进行离子注入的样品在99,435cm-1处出现两个ZnO六方纤锌相的特征峰E2low和E2high;N+和Xe+注入样品在130和578cm-1附近均出现新峰(包),N+注入样品还在274cm-1出现新峰,而Xe+注入样品在470cm-1附近出现另一新峰包,且这些新峰(包)的相对面积随注入剂量的增大而增大.通过N+和Xe+注入样品拉曼光谱的对比分析,并考虑到注入离子在样品中产生的原子位移损伤,对新峰(包)对应的振动模来源进行了分析,探索了离子注入在ZnO薄膜中引起的结构变化.

关键词： ZnO薄膜离子注入拉曼光谱

Nanocarrier-mediated siRNA delivery:a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2538-2555页

作者： Jie Jin Huajing Zhang Qianying Lu Linqiang Tian Sanqiao yao feng Lai Yangfan Liang Chuanchuan Liu Yujia Lu Sijia Tian Yanmei Zhao Wenjie Ren Institute of Disaster and Emergency Medicine Tianjin UniversityTianjinChina Key Laboratory for Disaster Medicine Technology TianjinChina Henan Medical Key Laboratory for Research of Trauma and Orthopedics The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiangHenan ProvinceChina Clinical Medical Center of Tissue Engineering and Regeneration Xinxiang Medical UniversityXinxiangHenan ProvinceChina Institutes of Health Central Plain Xinxiang Medical UniversityXinxiangHenan ProvinceChina School of Public Health Xinxiang Medical UniversityXinxiangHenan ProvinceChina

Traumatic brain injury and Alzheimer's disease share pathological similarities,including neuronal loss,amyloid-βdeposition,tau hyperphosphorylation,blood-brain barrier dysfunction,neuroinflammation,and cognitive ***,traumatic brain injury can exacerbate Alzheimer's disease-like pathologies,potentially leading to the development of Alzheimer's *** offer a potential solution by facilitating the delive ry of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease.U nlike traditional approaches to neuro regeneration,this is a molecula r-targeted strategy,thus avoiding non-specific drug *** review focuses on the use of nanocarrier systems for the efficient and precise delive ry of siRNAs,discussing the advantages,challenges,and future *** principle,siRNAs have the potential to target all genes and non-targetable protein s,holding significant promise for treating various *** the various therapeutic approaches currently available for neurological diseases,siRNA gene silencing can precisely"turn off"the expression of any gene at the genetic level,thus radically inhibiting disease progression;however,a significant challenge lies in delivering siRNAs across the blood-brain *** have received increasing attention as an innovative drug delive ry tool fo r the treatment of brain *** are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier,targeted drug delivery,enhanced drug stability,and multifunctional *** use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective *** this strategy is still in the preclinical exploration stage,it is expected to achieve clinical translation in the future,creating a new field of molecular tar

关键词： blood-brain barrier cognitive dysfunction exosomes gene silencing immunotherapy inorganic nanomaterials liposome nanoparticles neuroinflammation polymer nanoparticles stem cells

An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai Zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou feng Ding Yue Hu Jin Zhang Yagang yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory