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Electron mobility anisotropy in (Al,Ga)Sb/InAs two-dimensional electron gases epitaxied on GaAs (001) substrates

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Journal of Semiconductors 2022年第7期43卷 55-60页

作者： qiqi wei Hailong Wang Xupeng Zhao Jianhua Zhao State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China

The electron mobility anisotropy in (Al,Ga)Sb/InAs two-dimensional electron gases with different surface morphology has been investigated.Large electron mobility anisotropy is found for the sample with anisotropic morphology,which is mainly induced by the threading dislocations in the InAs layer.For the samples with isotropic morphology,the electron mobility is also anisotropic and could be attributed to the piezoelectric scattering.At low temperature (below transition temperature),the piezoelectric scattering is enhanced with the increase of temperature,leading to the increase of electron mobility anisotropy.At high temperature (above transition temperature),the phonon scattering becomes dominant.Because the phonon scattering is isotropic,the electron mobility anisotropy in all the samples would be reduced.Our results provide useful information for the comprehensive understanding of electron mobility anisotropy in the (Al,Ga)Sb/InAs system.

关键词： molecular-beam epitaxy (Al Ga)Sb/InAs two-dimensional electron gases electron mobility anisotropy piezoelectric scattering

Mn doping effects on the gate-tunable transport properties of Cd3As2 films epitaxied on GaAs

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Journal of Semiconductors 2020年第7期41卷 33-38页

作者： Hailong Wang Jialin Ma qiqi wei Jianhua Zhao State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering&CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Beijing Academy of Quantum Information Sciences Beijing 100193China

The Mn doping effects on the gate-tunable transport properties of topological Dirac semimetal Cd3As2 films have been investigated.Mn-doped Cd3As2 films are directly grown on GaAs(111)B substrates by molecular-beam epitaxy,during which the single crystal phase can be obtained with Mn concentration less than 2%.Shubnikov-de Haas oscillation and quantum Hall effect are observed at low temperatures,and electrons are found to be the dominant carrier in the whole temperature range.Higher Mn content results in smaller lattice constant,lower electron mobility and larger effective band gap,while the carrier density seems to be unaffected by Mn-doping.Gating experiments show that Shubnikov-de Haas oscillation and quantum Hall effect are slightly modulated by electric field,which can be explained by the variation of electron density.Our results provide useful information for understanding the magnetic element doping effects on the transport properties of Cd3As2 films.

关键词： molecular-beam epitaxy Dirac semimetal Cd3As2 film Mn doping quantum transport

污染环境下具有Markov切换的随机食饵-捕食渔业模型及其最优收获

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应用数学 2024年第2期37卷 303-320页

作者：钟琪琪韦煜明桂林医学院智能医学与生物技术学院广西桂林541199 广西师范大学数学与统计学院广西桂林541006

本文研究在污染环境中具有白噪声和Markov切换的随机食饵-捕食者渔业模型的最优收获策略.首先证明全局正解的存在唯一性,讨论种群灭绝和持久的阈值.通过构造适当的Lyapunov函数得到遍历平稳分布存在的充分条件.应用遍历方法研究模型的... 详细信息

本文研究在污染环境中具有白噪声和Markov切换的随机食饵-捕食者渔业模型的最优收获策略.首先证明全局正解的存在唯一性,讨论种群灭绝和持久的阈值.通过构造适当的Lyapunov函数得到遍历平稳分布存在的充分条件.应用遍历方法研究模型的最优收获策略.最后,提供一些数值模拟来证明理论分析.分析表明, Markov切换可以抑制种群的灭绝,而白噪声强度和污染物浓度对最优收获策略有明显的负面影响.

关键词：食饵-捕食者模型最优收获环境污染 Markov切换

基于ISMM方法的非均匀磁化等离子体湍流中电磁波传播特性研究

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电波科学学报 2024年第1期39卷 65-71页

作者：陈伟马琪琪杨利霞薄勇安徽大学电子信息工程学院合肥230601 目标探测与特征提取安徽省重点实验室合肥230601 先进激光技术安徽省实验室合肥230601

由于传统散射矩阵法(scattering matrix method, SMM)在计算过程中会产生奇异矩阵,本文基于改进的SMM (improved SMM, ISMM)结合一维磁化等离子体湍流模型,计算了等离子体湍流介质对电磁波在不同入射角下的反射系数和透射系数,同时分析... 详细信息

由于传统散射矩阵法(scattering matrix method, SMM)在计算过程中会产生奇异矩阵,本文基于改进的SMM (improved SMM, ISMM)结合一维磁化等离子体湍流模型,计算了等离子体湍流介质对电磁波在不同入射角下的反射系数和透射系数,同时分析了电磁波在非均匀磁化等离子体中的传播特性。结果表明,湍流的出现极大地影响了等离子体鞘套中电子的运动规律,使其运动过程中能量衰减增多,因此其在0~35 GHz的透射系数增大;另一方面外部磁场的增大,对左旋圆极化波与右旋圆极化波的传播特性影响相反,这是因为在左旋情况下,左旋圆极化波的旋转方向正好与电子的旋转方向相同,右旋圆极化波相反;随着入射角度的增大,相当于电磁波在等离子体湍流中的传播距离增大,导致更多的电磁波能量被吸收;此外,考虑非均匀磁化情况后,电磁波在0~35 GHz频段内的右旋圆极化的透射系数更大。这些结果为研究电磁波在非均匀磁化等离子体湍流介质的传播特性提供了理论依据。

关键词：非均匀磁化等离子体等离子体湍流改进的散射矩阵法(ISMM) 入射角

电感耦合等离子体质谱法与离子色谱法测定卷烟纸中镁含量的比较

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中华纸业 2024年第5期45卷 57-60页

作者：魏琦琦牡丹江恒丰纸业股份有限公司黑龙江牡丹江157013

采用电感耦合等离子体质谱法与离子色谱法分别检测卷烟纸中镁含量,对两种方法进行比较。结果表明:两种方法都可以准确地测出卷烟纸中镁含量,但离子色谱法的前处理方法更加简单安全,结果的稳定性、准确性与精密度更高,因而在检测中更具... 详细信息

采用电感耦合等离子体质谱法与离子色谱法分别检测卷烟纸中镁含量,对两种方法进行比较。结果表明:两种方法都可以准确地测出卷烟纸中镁含量,但离子色谱法的前处理方法更加简单安全,结果的稳定性、准确性与精密度更高,因而在检测中更具优势。

关键词：卷烟纸电感耦合等离子体质谱仪离子色谱镁

Rhesus monkeys exhibiting spontaneous ritualistic behaviors resembling obsessive-compulsive disorder

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National Science Review 2023年第11期10卷 34-44页

作者： Rongwei Zhai Geya Tong Zheqin Li weichen Song Yang Hu Sha Xu qiqi wei Xiaocheng Zhang Yi Li Bingbing Liao Chenyu Yuan Yinqing Fan Ge Song Yinyin Ouyang Wenxuan Zhang Yaqiu Tang Minghui Jin Yuxian Zhang He Li Zhi Yang Guan Ning Lin Dan J.Stein Zhi-Qi Xiong Zhen Wang Shanghai Mental Health Center Shanghai Jiao Tong University School of Medicine Institute of Neuroscience State Key Laboratory of NeuroscienceCAS Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of Sciences Lingang Laboratory 4. Shanghai Center for Brain Science and Brain-Inspired Technology Translational Neuropsychiatry Unit(TNU) Department of Clinical MedicineAarhus University Shanghai Key Laboratory of Psychotic Disorders Shanghai Mental Health CenterShanghai Jiao Tong University School of Medicine

Obsessive-compulsive disorder(OCD) is a chronic and debilitating psychiatric disorder that affects ～2%–3% of the population globally. Studying spontaneous OCD-like behaviors in non-human primates may improve our understanding of the disorder. In large rhesus monkey colonies, we found 10 monkeys spontaneously exhibiting persistent sequential motor behaviors(SMBs) in individual-specific sequences that were repetitive, time-consuming and stable over prolonged periods. Genetic analysis revealed severely damaging mutations in genes associated with OCD risk in humans. Brain imaging showed that monkeys with SMBs had larger gray matter(GM) volumes in the left caudate nucleus and lower fractional anisotropy of the corpus callosum. The GM volume of the left caudate nucleus correlated positively with the daily duration of SMBs. Notably, exposure to a stressor(human presence) significantly increased SMBs. In addition, fluoxetine, a serotonergic medication commonly used for OCD, decreased SMBs in these monkeys. These findings provide a novel foundation for developing better understanding and treatment of OCD.

关键词： obsessive-compulsive disorder (OCD) primate ritualistic behavior model OCD risk genes caudate nucleus fluoxetine

补阳还五汤对关节镜下小切口肩袖损伤修补缝合术后的短期影响

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光明中医 2024年第4期39卷 689-691页

作者：魏琦琦肖毅山东中医药大学山东济南250000 山东中医药大学附属医院微创骨科山东济南250000

目的观察补阳还五汤应用于关节镜下小切口肩袖损伤术后的短期临床疗效。方法将山东中医药大学附属医院微创骨科于2021年1月—2023年1月收治的60例患者随机分成2组,对照组(30例)进行正常康复训练,观察组(30例)加用补阳还五汤,持续4周。比... 详细信息

目的观察补阳还五汤应用于关节镜下小切口肩袖损伤术后的短期临床疗效。方法将山东中医药大学附属医院微创骨科于2021年1月—2023年1月收治的60例患者随机分成2组,对照组(30例)进行正常康复训练,观察组(30例)加用补阳还五汤,持续4周。比较2组患者肩关节功能独立性(FIM)、肩关节功能评分(Constant-Murley)等指标以及不良反应发生率。结果治疗4周后,2组FIM和Constant-Murley的评分较治疗前明显提高,且观察组高于对照组(P<0.05);2组均无明显不良反应。结论补阳还五汤加减应用于关节镜辅助下肩袖损伤缝合修补术后,能够帮助患者尽早恢复功能锻炼,促进肩关节健骨愈合,有效地促进患者早期恢复。

关键词：筋伤肩袖损伤补阳还五汤关节镜中医康复

LORELEI-LIKE GPI-ANCHORED PROTEINS 2/3 Regulate Pollen Tube Growth as Chaperones and Coreceptors for ANXUR/BUPS Receptor Kinases in Arabidopsis

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Molecular Plant 2019年第12期12卷 1612-1623页

作者： Hanqian Feng Chen Liu Rong Fu Minmin Zhang Hui Li Lianping Shen qiqi wei Xiang Sun Lin Xu Bin Ni Chao Li School of Life Sciences East China Normal UniversityShanghai 200241China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of Sciences300 Fenglin RoadShanghai 200032China

Pollen tube growth is crucial for successful fertilization.In Arabidopsis thaliana,the ANXUR(ANX)/BUPS receptor kinase complex controls and maintains pollen tube growth in response to autocrine rapid alkalin-ization factor 4/19(RALF4/19)signaling;however,the molecular and cellular mechanisms underlying the ANX/BUPS-mediated regulation of pollen tube growth remain unclear.In this study,we found that pollen-specific LORELEI-like GPI-anchored proteins 2 and 3(LLG2/3)promote pollen tube growth in vitro and in vivo.LLG2/3 interacte with ANX/BUPS in a RALF4-concentration-dependent manner,suggesting that ANX/BUPS and LLG2/3 might form a receptor-coreceptor complex for perceiving RALF peptide signals.Disruption of the ANX/BUPS-LLG2/3 interaction led to the cytoplasmic retention of ANX1/2,in either llg2/3 knockdown mutants or in anx1/2 mutants lacking the J region,which mediates the ANX/BUPS-LLG2/3 interaction.Moreover,we found that RALF4 induced the production of reactive oxygen species(ROS),which stimulate pollen tube growth and reduce pollen burst rate.ROS levels are reduced in the pollen tubes of LLG2/3 RNAi lines,and application of exogenous H2O2 could partially rescue the defective pollen tube growth of LLG2/3 RNAi lines.Taken together,our study identifies LLG2/3 as novel regulatory components of pollen tube growth,and shows that they chaperone ANX/BUPS for secretion to the apical plasma membrane of pollen tube and act as coreceptors of ANX/BUPS in the acti-vation of ROS production for promoting pollen tube growth.

关键词： reception complex secretion reactive oxygen species cell wall integrity

面向极限生存能力提升的城市配电网反脆弱规划方法

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电力建设 2024年第1期45卷 56-67页

作者：时珊珊张琪祁魏新迟刘晋萍王颖许寅国网上海市电力公司上海市200437 北京交通大学电气工程学院北京市100044

城市电网负荷密度高、重要负荷多,提升其在极端事件下的生存能力有助于保障重要用户不间断供电,提升电网反脆弱能力,减小极端事件带来的影响和损失。提出了面向极限生存能力提升的城市配电网反脆弱规划方法。首先,提出了基于随机规划理... 详细信息

城市电网负荷密度高、重要负荷多,提升其在极端事件下的生存能力有助于保障重要用户不间断供电,提升电网反脆弱能力,减小极端事件带来的影响和损失。提出了面向极限生存能力提升的城市配电网反脆弱规划方法。首先,提出了基于随机规划理论的城市配电网韧性规划两步骤决策框架,第一步确定候选线路加固/升级方案集合,第二步基于随机规划理论确定线路规划方案下的分布式电源最优部署方案,考虑投资经济性和极限生存能力提升效果等因素,确定最终韧性规划方案。其中,针对不同候选线路加固/升级方案,考虑可能遭遇的极端灾害,提出基于蒙特卡洛模拟和K-means聚类的极端场景生成及代表性场景筛选方法。其次,以投资经济性最优和极限生存能力提升最大化为目标,将分布式电源的规划问题构建为两阶段随机混合整数规划,并基于前述极端场景将随机规划转化为确定性的混合整数线性规划。最后,采用IEEE 33节点测试系统与123节点测试系统进行算例分析,验证所提方法的有效性。

关键词：城市配电网韧性反脆弱规划极端事件极限生存