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Valence-Shell Excitations of Nitrous Oxide Studied by Fast Electron Impact

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Chinese Physics Letters 2012年第4期29卷 65-67页

作者： LIU Ya-Wei WANG You-Yan zhu lin-fan Hefei National Laboratory for Physical Sciences at Microscale Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei 230026

The valence-shell excitations of nitrous oxide are studied by fast electron energy loss *** the spectra measured at 2.5keV and scattering angles of 3.5°-8.5°,it is found that the asymmetric peak of the transition B 1△ can be well fitted by Haarhoff-Van der linde function,while the symmetric peaks of the transitions of C1Π and D1∑+ can be well fitted by the Voigt *** parameters of the peak profiles of B1△,C1Π and D1∑+,i.e.,their energy level positions and linewidths,are *** the aid of these parameters,the overlapping spectra measured at the low-energy electron impact can be deconvolved,which provides the possibility to determine the quantitative differential cross *** present results also show that the peak profiles of the transitions of B1△,C1Π and D1∑+ are independent of the momentum transfer.

关键词： spectroscopy function fitted

Inner-Shell Excitations of 2p Electrons of Argon Investigated by Fast Electron Impact with High Resolution

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Chinese Physics Letters 2011年第5期28卷 92-95页

作者： REN lin-Mao WANG You-Yan LI Dong-Dong YUAN Zhen-Sheng zhu lin-fan Hefei National Laboratory for Physical Sciences at Microscale Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei 230026

Electron energy loss spectra of inner-shell excitations of 2p electrons of argon are measured at an incident electron energy of 2500eV and scattering angles of 0°and 4°.The dipole-forbidden transitions of 2_(p3/2)^(-1)4p and 2_(p3/2)^(-1)5p are observed in the measured spectra and assigned based on the calculations of the Cowan *** positions and line widths for the excitations of 2_(p3/2)^(-1)nl and 2_(p1/2)^(-1)nl(n≤5)of argon are *** present results show that the line widths of the electric quadrupole transitions of 2_(p3/2)^(-1)4p[5/2+3/2]_(2)and the electric monopole one of 2p_(3/2)^(-1)4p[1/2]0 are less than those of the dipole-allowed transitions.

关键词： Electron transitions dipole

Ar原子和K^(+)离子序列双光双电离光电子角分布的非偶极效应

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物理学报 2022年第6期71卷 102-111页

作者：马堃朱林繁颉录有黄山学院信息工程学院黄山245041 中国科学技术大学近代物理系合肥230026 西北师范大学物理与电子工程学院兰州730070

基于多组态Dirc-Fock方法和密度矩阵理论,给出了原子序列双光双电离光电子角分布的计算表达式,开发了相应的计算程序.利用该程序计算了Ar原子和K^(+)离子np(n=2,3)壳层的光电离截面、电偶极和非偶极角各向异性参数,进一步给出了光电子... 详细信息

基于多组态Dirc-Fock方法和密度矩阵理论,给出了原子序列双光双电离光电子角分布的计算表达式,开发了相应的计算程序.利用该程序计算了Ar原子和K^(+)离子np(n=2,3)壳层的光电离截面、电偶极和非偶极角各向异性参数,进一步给出了光电子的角分布情况.结果表明:在序列双光双电离中两次光电离过程相互影响,两次光电离的截面以及各向异性参数类似;在电离阈值附近,3p壳层和2p壳层光电离截面以及各向异性参数展现出较大的差异,在远离阈值时,3p和2p壳层的截面和角各向异性参数变化行为类似;在光电离截面的Cooper极小能量位置,电偶极的贡献被压制,凸显出非偶极效应的贡献.非偶极效应导致光电子相对于入射光方向出现前向-后向不对称分布.

关键词：序列双光双电离光电子角分布非偶极效应

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等离子体刻蚀建模中的电子碰撞截面数据

物理学报 2024年第9期73卷 1-25页

作者：陈锦峰朱林繁中国科学技术大学近代物理系合肥230026

半导体芯片是信息时代的基石,诸如大数据、机器学习、人工智能等新兴技术领域的快速发展离不开源自芯片层面的算力支撑.在越来越高的算力需求驱动下,芯片工艺不断追求更高的集成度与更小的器件体积.作为芯片制造工序的关键环节,刻蚀工... 详细信息

半导体芯片是信息时代的基石,诸如大数据、机器学习、人工智能等新兴技术领域的快速发展离不开源自芯片层面的算力支撑.在越来越高的算力需求驱动下,芯片工艺不断追求更高的集成度与更小的器件体积.作为芯片制造工序的关键环节,刻蚀工艺因此面临巨大的挑战.基于低温等离子体处理技术的干法刻蚀工艺是高精细电路图案刻蚀的首选方案,借助等离子体仿真模拟,人们已经能够在很大程度上缩小实验探索的范围,在海量的参数中找到最优工艺条件.电子碰撞截面是等离子体刻蚀模型的关键输入参数,深刻影响着模型预测结果的可靠性.本文主要介绍了低温等离子体建模的基本理论,重点强调电子碰撞截面数据在数值模拟中的重要作用.与此同时,本文概述了获取刻蚀气体截面数据的理论与实验方法.最后总结了刻蚀相关原子分子的电子碰撞截面研究现状,并展望了未来的研究前景.

关键词：电子碰撞截面干法刻蚀低温等离子体等离子体建模

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Selection rules for electric multipole transition of diatomic molecule in scattering experiments

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Chinese Physics B 2015年第4期24卷 1-5页

作者：朱林繁田红春刘亚伟康旭刘国兴 Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics University of Science and Technology of China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

The knowledge of the energy level structures of atoms and molecules is mainly obtained by spectroscopic experiments. Both photoabsorption and photoemission spectra are subject to the electric dipole selection rules （also known as optical selection rules）. However, the selection rules for atoms and molecules in the scattering experiments are not identical to those in the optical experiments. In this paper, based on the theory of the molecular point group, the selection rules are derived and summarized for the electric monopole, electric dipole, electric quadrupole, and electric octupole transitions of diatomic molecules under the first Born approximation in scattering experiments. Then based on the derived selection rules, the electron scattering spectra and x-ray scattering spectra of H2, N2, and CO at different momentum transfers are explained, and the discrepancies between the previous experimental results measured by different groups are elucidated.

关键词： selection rule molecular point group electron scattering x-ray scattering

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自适应轮廓的变分水平集复杂背景多目标检测

软件学报 2017年第10期28卷 2797-2810页

作者：冯冬竹范琳琳余航戴浩袁晓光西安电子科技大学空间科学与技术学院陕西西安710071 西安电子科技大学电子工程学院陕西西安710071

无需重新初始化的变分水平集模型能够避免经典水平集模型的重复初始化步骤,进而简化计算,缩短检测所需时间,同时能够有效利用图像的边缘梯度信息,从而准确定位图像的局部结构.但该模型不能自适应地获得初始化曲线,水平集的拓扑结构也无... 详细信息

无需重新初始化的变分水平集模型能够避免经典水平集模型的重复初始化步骤,进而简化计算,缩短检测所需时间,同时能够有效利用图像的边缘梯度信息,从而准确定位图像的局部结构.但该模型不能自适应地获得初始化曲线,水平集的拓扑结构也无法改变,不能解决多个目标的检测问题.针对以上问题,提出了一种基于自适应轮廓的变分水平集复杂背景多目标检测方法,该方法采用帧间差分算法与K-means聚类算法相结合,以获得多个运动目标的初始化曲线,通过形态学方法来降低图像噪声的干扰,从而快速自适应地估计复杂背景下运动目标的位置和轮廓大小.该算法进一步对无需初始化的变分水平集进行改进,将其由单目标检测模型扩展为多目标检测模型,并修正原模型难以处理图像灰度不均匀的问题,最终实现对复杂背景下多个目标的检测.在标准数据库和实际数据集上的测试结果表明,所提方法能够准确地定位不同尺度和灰度目标的轮廓,从而提高算法的演化迭代效率及准确性.

关键词：变分水平集帧间差分算法 K-means聚类算法形态学复杂背景

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-Gui Peng Peng Wu Zong-lin Li Xue-Feng zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Pharmacological targeting cGAS/STING/NF-κB axis by tryptanthrin induces microglia polarization toward M2 phenotype and promotes functional recovery in a mouse model of spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3287-3301页

作者： Ziwei fan Mengxian Jia Jian Zhou Zhoule zhu Yumin Wu Xiaowu lin Yiming Qian Jiashu Lian Xin Hua Jianhong Dong Zheyu fang Yuqing Liu Sibing Chen Xiumin Xue Juanqing Yue Minyu zhu Ying Wang Zhihui Huang Honglin Teng Department of Orthopedics(Spine Surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina School of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Neurology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina

The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord *** of shifting microglia polarization from M1(neurotoxic and proinflammatory type)to M2(neuroprotective and anti-inflammatory type)after spinal cord injury appears to be *** possesses an anti-inflammatory biological ***,its roles and the underlying molecular mechanisms in spinal cord injury remain *** this study,we found that tryptanthrin inhibited microglia-derived inflammation by promoting polarization to the M2 phenotype in *** promoted M2 polarization through inactivating the cGAS/STING/NF-κB ***,we found that targeting the cGAS/STING/NF-κB pathway with tryptanthrin shifted microglia from the M1 to M2 phenotype after spinal cord injury,inhibited neuronal loss,and promoted tissue repair and functional recovery in a mouse model of spinal cord ***,using a conditional co-culture system,we found that microglia treated with tryptanthrin suppressed endoplasmic reticulum stress-related neuronal *** together,these results suggest that by targeting the cGAS/STING/NF-κB axis,tryptanthrin attenuates microglia-derived neuroinflammation and promotes functional recovery after spinal cord injury through shifting microglia polarization to the M2 phenotype.

关键词： cGAS/STING functional recovery microglia neuroinflammation neuroprotection nuclear factor-κB polarization spinal cord injury tryptanthrin

Non-coding RNAs in acute ischemic stroke:from brain to periphery

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Neural Regeneration Research 2025年第1期20卷 116-129页

作者： Shuo Li Zhaohan Xu Shiyao Zhang Huiling Sun Xiaodan Qin lin zhu Teng Jiang Junshan Zhou Fuling Yan Qiwen Deng Department of Neurology Nanjing First HospitalNanjing Medical UniversityNanjingJiangsu ProvinceChina Department of Neurology Zhongda HospitalSchool of MedicineSoutheast UniversityNanjingJiangsu ProvinceChina General Clinical Research Center Nanjing First HospitalNanjing Medical UniversityNanjingJiangsu ProvinceChina

Acute ischemic stroke is a clinical emergency and a condition with high morbidity,mortality,and *** predictive,diagnostic,and prognostic biomarkers and effective therapeutic targets for acute ischemic stroke remain *** innovations in high-throughput gene sequencing analysis,many aberrantly expressed non-coding RNAs(ncRNAs)in the brain and peripheral blood after acute ischemic stroke have been found in clinical samples and experimental *** expressed ncRNAs in the post-stroke brain were demonstrated to play vital roles in pathological processes,leading to neuroprotection or deterioration,thus ncRNAs can serve as therapeutic targets in acute ischemic ***,distinctly expressed ncRNAs in the peripheral blood can be used as biomarkers for acute ischemic stroke prediction,diagnosis,and *** particular,ncRNAs in peripheral immune cells were recently shown to be involved in the peripheral and brain immune response after acute ischemic *** this review,we consolidate the latest progress of research into the roles of ncRNAs(microRNAs,long ncRNAs,and circular RNAs)in the pathological processes of acute ischemic stroke–induced brain damage,as well as the potential of these ncRNAs to act as biomarkers for acute ischemic stroke prediction,diagnosis,and *** from this review will provide novel ideas for the clinical application of ncRNAs in acute ischemic stroke.

关键词： acute ischemic stroke apoptosis blood–brain barrier damage circular RNAs excitatory toxicity long non-coding RNAs microRNAs neuroinflammation non-coding RNAs oxidative stress