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Ultrafast(600 ps)α-ray scintillators

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PhotoniX 2022年第1期3卷 350-361页

作者： Richeng Lin Yanming Zhu Liang Chen Wei Zheng mengxuan xu Jinlu Ruan Renfu Li Titao Li Zhuogeng Lin Lu Cheng Ying Ding Feng Huang Xiaoping Ouyang State Key Laboratory of Optoelectronic Materials and Technologies School of MaterialsSun Yat-Sen UniversityGuangzhou 510275China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect and Radiation Detection Research Center Northwest Institute of Nuclear TechnologyXi’an 710024China School of Nuclear Science and Technology Xi’an Jiaotong UniversityXi’an 710049China CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Key Laboratory of NanomaterialsFujian Institute of Research On the Structure of MatterChinese Academy of SciencesFuzhou 350002China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China.

Large-size scintillators with high efficiency and ultrafast radiation fluorescence have shown more potential in the applications to ionizing radiation detection of medical diagnosis,nuclear control and high-energy ***,although traditional scintillators have made tremendous progress in scintillation efficiency,there are still challenges left in fluorescence *** with that problem,we adopted 2-inch ZnO as the substrate and doped gallium as activator to realize an ultrafast fluorescence excited byα-ray,of which the decay time is only 600 ps that is the shortest scintilla-tion decay time reported so *** results show that the shallow donor related with gallium not only effectively suppresses band-edge self-absorption,but makes ultrafast radiation possible,which gets gallium-doped ZnO as a potential scintillator for high-quality ultrafast dynamic imaging proved.

关键词： Scintillators Gallium doped zinc oxide Decay time Radioluminescence

“在地性”与“民间化”的转向、挑战——有关“近十年来中国当代艺术创作的主要观念及动向”论坛

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当代美术家 2020年第3期 36-39页

作者：徐萌轩不详

本篇文章是对于"近十年来中国当代艺术创作的主要观念及动向"论坛的思考。笔者基于一种艺术史分期的合理性角度,先梳理了金融危机过后的2009年到2019年间当代艺术市场的变化。其次,我们发现在这十年的低迷的当代艺术市场经济中,长时间... 详细信息

本篇文章是对于"近十年来中国当代艺术创作的主要观念及动向"论坛的思考。笔者基于一种艺术史分期的合理性角度,先梳理了金融危机过后的2009年到2019年间当代艺术市场的变化。其次,我们发现在这十年的低迷的当代艺术市场经济中,长时间被经济主导的当代艺术中被遮蔽的项目式艺术开始盛行,它们呈现出"在地性"与"民间化"的倾向。这种倾向瓦解了此前二元对立的话语模式并书写了一种新的当代性,然而当代性与危险并存--它们又面临着被庸俗化与被规训的危机。因此近十年来中国当代艺术呈现"在地性"与"民间化"转向与被庸俗化与被规训的挑战并存的局面。"近十年来中国当代艺术创作的主要观念及动向"论坛展现的是一种辩证的思考,以此希望引起更广泛的讨论。

关键词：在地性民间社会剧场

马尾松细胞分裂素羟化酶基因PmCYP735A克隆与表达分析

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广西植物 2020年第6期40卷 864-872页

作者：徐梦璇吴玲类彦东徐立安胥猛南京林业大学南方现代林业协同创新中心南京210037 南京林业大学林学院南京210037

该文首次在针叶树种马尾松(Pinus massoniana)中采用cDNA末端快速克隆(RACE)技术克隆,并鉴定出1个CYP735A基因。结果表明:马尾松CYP735A基因(PmCYP735A)cDNA全长为1744 bp,包括1647 bp的开放阅读框,44 bp的5’端非翻译区和53 bp的3’端... 详细信息

该文首次在针叶树种马尾松(Pinus massoniana)中采用cDNA末端快速克隆(RACE)技术克隆,并鉴定出1个CYP735A基因。结果表明:马尾松CYP735A基因(PmCYP735A)cDNA全长为1744 bp,包括1647 bp的开放阅读框,44 bp的5’端非翻译区和53 bp的3’端非翻译区。该基因编码蛋白由548个氨基酸残基组成,其二级结构含有丰富的α-螺旋和无规则卷曲。该基因编码蛋白不含跨膜区域,且无信号肽酶切位点,在399~406个和475~484个氨基酸残基存在P450超家族保守特征序列ETLRLYP(ExxRxxP)和血红素结合区域(Heme-binding region)FSFGPRKCVG(FxxGxRxCxG)。系统进化树分析表明,马尾松PmCYP735A与水稻、玉米、拟南芥CYP735A蛋白归属于同一小的进化枝,可可、毛果杨、麻风树和橡胶树等的CYP735A同源蛋白相对集中的定位于另一进化分支。实时定量PCR检测发现,PmCYP735A基因在马尾松根和茎中的表达量显著高于叶,该基因响应外源生长素NAA诱导表达,随着诱导时间呈现先上升再下降的表达趋势。以上结果有助于深入探究CYP735A基因家族的生物学功能及其在物种间的表达调控异同,为进一步挖掘马尾松优异基因资源奠定基础。

关键词：细胞分裂素羟化酶 RACE 表达模式马尾松系统进化分析

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北京山区推理公式设计洪水计算若干问题研究

北京水务 2021年第5期 51-57页

作者：许梦璇高振宇北京北咨工程项目管理咨询有限公司北京100124 北京市工程咨询有限公司北京100124

北京山区推理公式是北京地区无资料山区小流域设计洪水计算的基本方法之一。结合北京山区原推理公式与改进后推理公式存在问题,分析了利用推理公式计算山区小流域设计洪水的适用性和可靠性,并提出相关使用建议。针对当前推理公式方法计... 详细信息

北京山区推理公式是北京地区无资料山区小流域设计洪水计算的基本方法之一。结合北京山区原推理公式与改进后推理公式存在问题,分析了利用推理公式计算山区小流域设计洪水的适用性和可靠性,并提出相关使用建议。针对当前推理公式方法计算设计洪峰流量与洪水过程线计算中采用的降雨和径流资料不一致问题,提出将山区推理公式与瞬时单位线方法组合应用,解决无资料小流域设计洪水过程线计算的基本思路和方法s研究表明,该方法理论上可行,方法更为合理,建议推广使用。

关键词：设计洪水计算推理公式瞬时单位线组合应用

Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis

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Neural Regeneration Research 2025年第2期20卷 354-365页

作者： Li xu Huiming xu Changyong Tang Department of Neurology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor *** date,no effective treatment exists as the exact causative mechanism remains ***,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic *** most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets *** experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum *** this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model *** addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials.

关键词： aquaporin-4 experimental model neuromyelitis optica spectrum disorder pathogenesis

Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 64-70页

作者： Guo-Fu xu Department of Physics Shandong University

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era, building accurate intermediate-scale nonadiabatic holonomic quantum computers is clearly necessary. Given that measurements are the sole means of extracting information, they play an indispensable role in nonadiabatic holonomic quantum computers. Accordingly, developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great importance. However, while much attention has been given to the research on nonadiabatic holonomic gates, the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely lacking. In this study, we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum computers. The reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic gates. Given these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

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Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi xu Junqiu Jia Rui Mao Xiang Cao Yun xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review,we provide a comprehensive overview of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury

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Yb:YAG晶体性能实验测量

强激光与粒子束 2017年第8期29卷 143-147页

作者：严维鹏李斌康宋顾周段宝军姚志明宋岩韩长材许梦轩西北核技术研究所强脉冲辐射环境模拟与效应国家重点实验室西安710024 西安交通大学能源与动力工程学院西安710049

为了测量脉冲时间宽度小于20ns时的γ射线时间分辨图像,发展了新型无机闪烁体Yb:YAG,并实验测量了晶体的发光衰减时间、X射线激发发光光谱、相对发光效率和空间分辨等性能,研究了Yb:YAG晶体的发光性能。实验表明,Yb:YAG发光有三种衰减成... 详细信息

为了测量脉冲时间宽度小于20ns时的γ射线时间分辨图像,发展了新型无机闪烁体Yb:YAG,并实验测量了晶体的发光衰减时间、X射线激发发光光谱、相对发光效率和空间分辨等性能,研究了Yb:YAG晶体的发光性能。实验表明,Yb:YAG发光有三种衰减成分,快成分衰减常数为1.2ns,慢成分衰减常数与射线种类有关;X射线激发发光光谱在250~800nm范围,有三个发光峰,分别为320,380和500nm,且320nm处强度最大;相对发光效率为1900ph/MeV;使用钨分辨卡测得Yb:YAG空间分辨能力为2lp/m,使用刀口法测得空间调制传递函数为0.5时的频率为0.7lp/mm。结果说明Yb:YAG晶体性能能够满足所需测量要求。

关键词：时间宽度 Yb:YAG晶体衰减时间发光光谱相对发光效率空间分辨

一维天然河道水面线方程的敛散性成因及解决对策

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水科学与工程技术 2024年第4期 29-33页

作者：许梦璇马振梅高振宇北京市工程咨询股份有限公司北京100025

河道水面线计算是河道治理工程规划设计的主要内容之一,水面线计算的精度直接影响工程安全和设计质量。天然河道水面线计算通常是通过求解天然河道水面线方程得到。水面线方程虽然简单,但方程中各水力要素相互影响、相互制约,特别是天... 详细信息

河道水面线计算是河道治理工程规划设计的主要内容之一,水面线计算的精度直接影响工程安全和设计质量。天然河道水面线计算通常是通过求解天然河道水面线方程得到。水面线方程虽然简单,但方程中各水力要素相互影响、相互制约,特别是天然河道复式断面,由于断面形态复杂,河道纵坡沿程变化较大,缓流、急流转换十分常见,在河道水面线计算时往往会出现在某些断面水面线计算不收敛,或水位计算不合理的情况。结合工程实践及水面线算法设计经验,总结水面线方程求解过程中的关键环节,提出改进一维天然河道水面线方程敛散性的方法和思路,经实践检验,取得较好的效果。

关键词：天然河道水面线方程敛散性