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正交光楔列阵光学系统的小尺度不均匀性

光学精密工程 2009年第1期17卷 38-44页

作者：郑建洲于清旭关寿华大连理工大学应用物理与光电技术学院辽宁大连116024 大连民族学院理学院辽宁大连116600

推导出了正交光楔列阵(CSWA)聚焦系统的多光束干涉条纹主极大和两相邻主极大间的次极大间距公式,并根据广义惠更斯-菲涅耳衍射积分理论,通过数值计算证明了CSWA的小尺度不均匀性的变化规律与物理光学的公式符合。另外,提出改善小尺度不... 详细信息

推导出了正交光楔列阵(CSWA)聚焦系统的多光束干涉条纹主极大和两相邻主极大间的次极大间距公式,并根据广义惠更斯-菲涅耳衍射积分理论,通过数值计算证明了CSWA的小尺度不均匀性的变化规律与物理光学的公式符合。另外,提出改善小尺度不均匀性的两种方法:楔角偏差和离焦打靶技术。计算分析和实验研究表明,优化楔角偏差和离焦量的量值,即δpj=2.0%,ΔZ=2 mm时,干涉主极大间隔与没加这两种技术时相比减小了6倍,小尺度的不均匀性得到了明显的改善。

关键词：激光技术小尺度不均匀性正交光楔列阵楔角偏差离焦打靶

Mechanism Study on the Effect of Retarder on Polyurethane Setting Time Based on Molecular Simulation

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 224-231页

作者： WU yuxuan xu Wenyuan yu Tianlai JI Yongcheng School of Civil Engineering Northeast Forestry UniversityHarbin 150040China

This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal *** mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics *** transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane *** results demonstrate that a 1%concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of *** phosphate ester is added to the B component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component B on the surface of component *** reduction in interaction slows the setting ***,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate.

关键词： polyurethane retarder setting time molecular dynamics diffusion coefficient

Boosting Photocatalytic Performance of Cu-Mn Co-doped CeO_(2) Nanoparticles for Tetracycline Degradation

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 42-48页

作者： xu Rongqi MI Jianxin WANG Shulin xu Man ZHU Li BAI Lei TANG Dandan LEI yu Engineering Research Center of Environmental Materials and Membrane Technology of Hubei Province School of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Shaanxi Coal Chemical Industry Technology Research Institute Co. Ltd.Xi’an 710100China

Cu-Mn co-doped CeO_(2) photocatalyst was successfully synthesized by the sol-gel method to assess its capability in degrading *** and TEM results showed that Cu and Mn were successfully co-doped into CeO_(2) without forming heterostructure,XPS and photoelectrochemical results revealed that Mn ions doping amplified the generation of photo-induced charge carriers,while Cu ions doping significantly facilitated the interfacial charge transfer ***,the optimized Cu3Mn2CeO_(2) nanoparticles exhibited the highest TC removal efficiency,achieved a rate of 78.18%and maintained a stable cycling performance.

关键词： photocatalyst co-doped charge separation water treatment

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

低温3.0～4.2μm波段第一泛频一氧化碳激光器

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大连理工大学学报 2009年第4期49卷 617-624页

作者：林钧岫王晓旭于清旭大连理工大学物理与光电工程学院辽宁大连116024

根据国内外近30年来在一氧化碳激光器领域内的研究成果，从理论和实验两个方面论述若使第一泛频（△v=2）一氧化碳激光器在3．0～4．2μm波段成功运转．并能提供一定的输出能量，则必须对激光增益介质进行有效低温冷却的原因，并指出其... 详细信息

根据国内外近30年来在一氧化碳激光器领域内的研究成果，从理论和实验两个方面论述若使第一泛频（△v=2）一氧化碳激光器在3．0～4．2μm波段成功运转．并能提供一定的输出能量，则必须对激光增益介质进行有效低温冷却的原因，并指出其长波端的极限值．理论上分析了一氧化碳分子电子基态X^1∑^＋中，高振动激发态的粒子布居数和小信号增益系数对激光放电等离子体温度的强烈依赖关系；分析了一氧化碳分子的能级结构，在常规的稳态动力学模型中引入了X^1∑^＋→A^1Ⅱ传能项，该传能项限定了第一泛频一氧化碳激光的长波端极限．理论分析和计算与国外同行的实验结果相吻合．

关键词：低温冷却 V-V泵浦长波端极限

Recent progress in exploring heterogeneous catalyst surface chemistry with near ambient pressure XPS

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Science China Chemistry 2025年

作者： yuanjie xu Zemin An yu Tang Institute of Molecular Engineering Plus Institute of Molecule Catalysis and In Situ/Operando Studies College of Chemistry Fuzhou University

X-ray photoelectron spectroscopy(XPS) is a crucial surface analysis technique that has become a key tool in the study of heterogeneous catalysis. Detecting surface chemistry under conditions that closely mimic actual industrial catalytic processes is essential for understanding the mechanisms involved. In the past decade, near ambient pressure X-ray photoelectron spectroscopy(NAP-XPS) has been increasingly utilized to study the surface chemistry of catalysts during heterogeneous catalytic processes, offering insights into structure-performance correlations. This review begins with a brief overview of NAP-XPS instrumentation. Next, we discuss the application of NAP-XPS in the study of thermal catalysis reactions, followed by a summary of the research on catalyst restructuring under reaction conditions. Additionally, we address the challenges and future perspectives for the development and application of NAP-XPS. Catalysis is inherently dynamic, requiring an understanding of the real-time behavior of catalysts under varying conditions. Therefore, future improvements in the ability to probe reaction intermediates with higher spatial and temporal resolution under conditions that closely mimic industrial environments are needed.

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基于F-P腔的干涉/强度调制型光纤温度传感器

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中国激光 2005年第2期32卷 228-231页

作者：张桂菊于清旭宋世德大连理工大学物理系辽宁大连116024

介绍了一种基于非本征F-P腔的干涉/强度调制型光纤温度传感器.宽谱光源发光二极管(LED)发出的光经过2×2耦合器C1传给F-P传感头,传感头返回光信号再次经过耦合器C1及C2后分成两路,一路直接传给光电探测器D1,另一路经过窄带滤光片再传给... 详细信息

介绍了一种基于非本征F-P腔的干涉/强度调制型光纤温度传感器.宽谱光源发光二极管(LED)发出的光经过2×2耦合器C1传给F-P传感头,传感头返回光信号再次经过耦合器C1及C2后分成两路,一路直接传给光电探测器D1,另一路经过窄带滤光片再传给D2,光信号经光电转换及放大后由计算机采集处理.给出了采用不同谱宽的两路光信号进行自补偿运算和温度测量的理论模型,并简单分析了影响这一温度传感器长期稳定性的原因.实验中利用Levenberg-Marquardt非线性拟合得到与理论模型符合很好的温度定标曲线.该传感器在20～200℃量程内,温度变化最小分辨率达到0.1℃,长期测量精度达到±0.2℃.

关键词：光纤光学光纤温度传感器 F-P腔干涉/强度调制自补偿

Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 204-251页

作者： Jiawen Hu Xinwei Li Qianqian Liang Li xu Changsheng Ding yu Liu Yanfeng Gao School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China

Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural ***,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in ***,it is of significance to boost the sodium storage performance of NVP cathode *** to now,many methods have been developed to optimize the electrochemical performance of NVP cathode *** this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology *** foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so ***,the challenges and prospects of high-performance NVP cathode material are also put *** is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs.

关键词： Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies

Mainchain conformation ordering self-assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2025年第1期68卷 329-336页

作者： yuzhu Li yumeng Gao Feng Tian yu Wang yuan Yao Shaoliang Lin Xiang Ma Binbin xu Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Key Laboratory for Advance Materials and Feringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular Engineering East China University of Science & Technology

Developing organic room-temperature phosphorescence （RTP） materials with a wide range of tunable-emission is significant in expanding the applications of RTP ***,we rationally designed amphiphilic alternating copolymers poly(1,2-bis（4-alkoxyphenyl）ethane-1,2-dione-alt-（ethylene glycol）x)(P（Bz-alt-EGx）) that combined the advantage of alternating benzil and EGxskeleton,and tunable mainchain *** a mainchain conformation ordering assembly （COA） process,P（Bz-alt-EGx） self-assembled into well-defined platelets,and such assemblies emitted blue RTP at ca.425 nm due to the ordered folded-chain conformation and confined *** contrast,traditional self-assembly （TA） of P（Bz-alt-EGx） obtained less ordered aggregates,such as asymmetric worms,vesicles,and rod-like *** resultant less ordered aggregates exhibited yellow-green RTP at ca.550 *** wide-tuning RTP emission in solution （between blue and yellow-green,over125 nm） is realized using the P（Bz-alt-EGx） alternating copolymers under the treatment of different self-assembly *** study uncovers a new strategy to tailor the RTP emission through different self-assembly pathways and holds great promise for the fabrication of advanced optical materials.

关键词： self-assembly conformation ordering alternating copolymer phosphorescence emission