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高倍增超快高压GaAs光电导开关触发瞬态特性分析

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电子学报 2000年第2期28卷 20-23页

作者：施卫梁振宪西安理工大学应用物理系西安交通大学电气工程学院西安710049

首次提出“发光畴”模型对强电场下GaAs光电导开关高倍增工作模式的物理机制进行解释 .其要点是 :光注入载流子引起开关电场畸变 ,开关偏置在触发电场阈值下因负阻效应产生高场畴 ,畴内发生碰撞电离引起载流子的雪崩倍增 ,相伴而生的辐... 详细信息

首次提出“发光畴”模型对强电场下GaAs光电导开关高倍增工作模式的物理机制进行解释 .其要点是 :光注入载流子引起开关电场畸变 ,开关偏置在触发电场阈值下因负阻效应产生高场畴 ,畴内发生碰撞电离引起载流子的雪崩倍增 ,相伴而生的辐射复合发射光子替代了已消失的触发光脉冲 ,畴的运动与发光使载流子以 10 8cm/s的速度穿越电极间隙 ,畴生存条件决定Lock on电场 ,当外电路的控制使开关电场不能维持畴的生存时。

关键词：光电导开关砷化镓瞬态特性

Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing He zhen Wang Yuchen Wang Mengjie Zhu Zhile liang Kanghong Zhang Yuge Xu Gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis

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Neural Regeneration Research 2025年第7期20卷 2029-2037页

作者： Xiao liang Xingping Quan Xiaorui Geng Yujing Huang Yonghua Zhao Lei Xi zhen Yuan Ping Wang Bin Liu Faculty of Health Sciences University of MacaoMacao Special Administrative RegionChina Center for Cognitive and Brain Sciences University of MacaoMacao Special Administrative RegionChina Department of Biomedical Engineering Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina Department of Emergency Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral ***,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly *** this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed *** observed the molding process in mice of different ages and presented age-dependent vascular embolism ***,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a *** imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.

关键词： age-dependent cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy photothrombosis vascular imaging

Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： Ruo-Hang Xu Hao-Yu Jiang Dan-Dan Cui Kun-Rong Du Hong-Run Zhang Sheng-Jie Xu Ya-Qi Li Zhi-zhen Ren liang Wang Wei-Chang Hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts

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基于混合编程的HPN仿真

计算机仿真 2006年第11期23卷 284-286,345页

作者：梁贤贞李宏光北京化工大学信息科学与技术学院北京100029

混合Petri网(HPN)是离散事件和连续时间变量在同一层次的直接交互,其混合变迁规则较为复杂,既要考虑到离散部分与连续部分之间的相互影响,又要考虑到连续标识和离散标识之间的相互转化,所以如果选用单一语言来对混合Petri网进行仿真,难... 详细信息

混合Petri网(HPN)是离散事件和连续时间变量在同一层次的直接交互,其混合变迁规则较为复杂,既要考虑到离散部分与连续部分之间的相互影响,又要考虑到连续标识和离散标识之间的相互转化,所以如果选用单一语言来对混合Petri网进行仿真,难度高,编程量大,开发周期长,针对这一现象,该文提出混合编程的思想,即充分发挥不同编程语言的优势来仿真混合Petri网。该文采用了Matlab与Vc++混合编程的方法来进行混合Petri网的仿真,此种方法可以很好的实现对混合Petri网的仿真,并通过混合变迁规则来验证所建HPN模型的正确性,而且由于混编的应用大大减少了编程工作量,缩短了开发周期。最后针对一个蒸发过程进行实例研究。

关键词：混合派粹网仿真混合编程

Quantitative Trait Loci Mapping of Leaf Morphological Traits and Chlorophyll Content in Cultivated Tetraploid Cotton

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Journal of Integrative Plant Biology 2005年第11期47卷 1382-1390页

作者： xian-liang SONG Wang-zhen GUO Zhi-Guo HAN Tian-zhen ZHANG State Key Laboratory of Crop Genetics and Germplasm Enhancement Cotton Research Institute Nanjing Agricultural University Nanjing 210095 China Shandong Agricultural University College of Agronomy Taian 271018 China

Genetic mapping provides a powerful tool for quantitative trait loci （QTL） analysis at the molecular level. A simple sequence repeat （SSR） genetic map containing 590 markers and a BCI population from two cultivated tetraploid cotton （Gossypium hirsutum L.） cultivars, namely TM-1 and Hai 7124 （G. barbadense L.）, were used to map and analyze QTL using the composite interval mapping （CIM） method. Thirty one QTLs, 10 for lobe length, 13 for lobe width, six for lobe angle, and two for leaf chlorophyll content, were detected on 15 chromosomes or linkage groups at logarithm of odds （LOD）≥2.0, of which 15 were found for leaf morphology at LOD≥3.0. The genetic effects of the QTL were estimated. These results are fundamental for marker-assisted selection （MAS） of these traits in tetraploid cotton breeding.

关键词： chlorophyll cotton leaf morphology quantitative trait locus mapping simple sequencerepeat.

Performance of Ag_(2)O/Ag Electrode as Cathodic Electron Acceptor in Microbial Fuel Cell

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Acta Metallurgica Sinica(English Letters) 2017年第12期30卷 1243-1248页

作者： Hong-Yan Dai Hui-Min Yang Xuan Jian xian Liu zhen-Hai liang College of Chemistry and Chemical Engineering Taiyuan University of Technology Department of Municipal and Environmental Engineering Taiyuan College Department of Chemistry Taiyuan Normal University

An Ag2O/Ag electrode was prepared through the electrochemical oxidation of sterling silver. This electrode was used as a cathodic electron acceptor in a microbial fuel cell （MFC）. The Ag2O/Ag electrode was characterized by scanning electron microscopy, X-ray powder diffraction and linear sweep voltammetry. The maximum voltage output of the MFC with the AgaO/Ag cathode was maintained at between 0.47 and 0.5 V in 100 cycles, indicating the good regenerative capacity of the Ag2O/Ag electrode. The overpotential loss for silver oxide was 0.021-0.006 V, and the maximum power output, open circuit potential and short circuit current of the MFC were 1.796 W m^-3, 0.559 V and 9.3375 A m^-3, respectively. The energy required for electrochemical reoxidation ranged from 40% to 55% of the energy produced by the MFC. Results indicated that the AgeO/Ag electrode could be used as a cathodic electron acceptor in MFCs with excellent stability.

关键词： Ag2O/Ag electrode Cathodic electron acceptor Microbial fuel cell Regenerative capacity Overpotential loss Stability

Electricity Production in Microbial Fuel Cell Subjected to Different Operational Modes

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Acta Metallurgica Sinica(English Letters) 2016年第5期29卷 483-490页

作者： Hong-Yan Dai Hui-Min Yang xian Liu Xuan Jian zhen-Hai liang College of Chemistry and Chemical Engineering Taiyuan University of Technology Department of Environmental Engineering Taiyuan College

The effects of inoculum species, substrate concentration, temperature, and cathodic electron acceptors on electricity production of microbial fuel cells （MFCs） were investigated in terms of start-up time and power output. When inoculated with aeration tank sludge, this MFC outperformed the cell that was inoculated with anaerobic sludge in terms of start-up time and power output. After running for a certain time period, the dominant populations of the two MFCs varied significantly. Within the tested range of substrate concentration （200-1800 mg L-l）, the voltage output increased and the time span of the electricity generation lengthened with increasing substrate concentration. As the temperature declined from 35 to 10 ℃, the maximum power density reduced from 2.229 to 1.620 W m-3, and anodic polarization resistance correspondingly dropped from 118 to 98 Ω. The voltage output of MFC-Cu2＋ was 0.447 V, which is slightly lower than that achieved with MFC-[Fe（CN）6]3- （0.492 V）, thereby indicating that MFCs could be used to treat wastewater con- taining Cu2＋ pollutant in the cathode chamber with removal of organics in anode chamber and simultaneous electricity generation.

关键词： Microbial fuel cells Inoculum species Cathodic electron acceptors Electricity production

A novel derivative of geldanamycin and its antitumor activity

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Chinese Chemical Letters 2009年第4期20卷 391-392页

作者： liang Li Hong Liu xian Dong Xu Yong Su zhen Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

A new derivative of geldanamycin was synthesized by introducing the 6-cinnamamido-hexyl-amino group into the 17-site of geldanamycin, a heat shock protein 90 （Hsp90） inhibitor, to obtain 17-（6-cinnamamido-hexylamino）-17-demethoxygel-danamycin （CNDG）. Its in vitro and in vivo antitumor effects were evaluated by MTT assay and xenograft in nude mice.

关键词： 17-(6-Cinnamamido-hexylamino)-17-demethoxygeldanamycin Hsp90 inhibitor