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Tracking coherent low frequency vibrational information of Rh101 in ground and excited electronic states by broadband transient grating spectroscopy

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Chinese Physics B 2018年第12期27卷 231-237页

作者： Wei Zhang Xiao-Song Liu Zan-Hao Wang Yun-Fei Song yan-qiang yang Department of Physics Harbin Institute of TechnologyHarbin 150001China National Key Laboratory of Shock Wave and Detonation Physics Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyang 621900China

Time-and frequency-resolved broadband transient grating(BB-TG) spectroscopy is used to distinguish between ground-and excite-electronic state vibrational coherence at different wavelengths. Qualitative theoretical analysis using double-sided Feynman diagrams indicates that a superposition of ground and excited state vibrational coherence are contained in the ground state absorption(GSA) and stimulated emission(SE) overlap band, while only the excited state is contained in the excited state absorption(ESA) band. The TG experiment, in which a white light continuum(WLC) is adopted as a probe, is conducted with rhodamine101(Rh101~+) as the target molecule. Fourier analysis of TG dynamics in a positive delay time range at specific wavelengths enables us to distinguish the low-frequency vibrational modes of Rh101 in ground-and excite-electronic states.

关键词： transient grating Rh101 low-frequency Raman vibrational spectrum

Scanning the energy dissipation process of energetic materials based on excited state relaxation and vibration–vibration coupling

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Chinese Physics B 2018年第10期27卷 341-345页

作者： Wen-yan Wang Ning Sui Li-Quan Zhang Ying-Hui Wang Lin Wang Quan Wang Jiao Wang Zhi-Hui Kang yan-qiang yang qiang Zhou Han-Zhuang Zhang Femtosecond Laser Laboratory Key Laboratory of Physics and Technology for Advanced Batteries（Ministry of Education）College of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China National Key Laboratory of Shock Wave and Detonation Physics Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyang 621900China

The energy dissipation mechanism of energetic materials（EMs） is very important for keeping safety. We choose nitrobenzene as a model of EM and employ transient absorption（TA） spectroscopy and time-resolved coherent anti-stokes Raman scattering（CARS） to clarify its energy dissipation mechanism. The TA data confirms that the excited nitrobenzene spends about 16 ps finishing the twist intramolecular charge transfer from benzene to nitro group, and dissipates its energy through the rapid vibration relaxation in the initial excited state. And then the dynamics of vibrational modes（VMs） in the ground state of nitrobenzene, which are located at 682 cm^-1（v1）, 854 cm^-1（v2）, 1006 cm^-1（v3）, and 1023 cm^-1（v4）,is scanned by CARS. It exhibits that the excess energy of nitrobenzene on the ground state would further dissipate through intramolecular vibrational redistribution based on the vibrational cooling of vi and v2 modes, v1 and v4 modes, and v3 and v4 modes. Moreover, the vibration-vibration coupling depends not only on the energy levels of VMs, but also on the spatial position of chemical bonds relative to the VM.

关键词： energy dissipation charge transfer transient absorption coherent anti-stokes Raman scattering(CARS)

“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage

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Nano-Micro Letters 2025年第1期17卷 348-360页

作者： yan Zhao qiang Yuan Liting yang Guisheng Liang Yifeng Cheng Limin Wu Chunfu Lin Renchao Che College of Physics Donghua UniversityShanghai 201620People’s Republic of China School of Materials Science and Engineering Institute of Materials for Energy and EnvironmentQingdao UniversityQingdao 266071People’s Republic of China Laboratory of Advanced Materials Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsAcademy for Engineering&TechnologyFudan UniversityShanghai 200438People’s Republic of China Zhejiang Laboratory Hangzhou 311100People’s Republic of China Inner Mongolia University Hohhot 010021People’s Republic of China

Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte ***,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term ***,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical *** Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O *** superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries.

关键词： NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization

Photo-Induced Intermolecular Electron Transfer-Effect of Acceptor Molecular Structures

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Chinese Journal of Chemical Physics 2018年第6期31卷 772-778,733页

作者： Wei Zhang Xiao-song Liu Lin yan Gang-bei Zhu Zan-hao Wang yan-qiang yang Department of Physics Harbin institute of Technology Harbin 150001 China National Key Laboratory of Shock Wave and Detonation Physics Institute of Fluid Physics Chinese Academy of Engineering Physics Mianyang 621900 China

Photo-induced electron transfer versus molecular structure of acceptors is investigated using ultrafast time-resolved transient grating spectroscopy. Typical laser dyes Rhodamine 101 (Rh101) and Rhodamine 6G (Rh6G) in electron donor solvent-aniline are adopted as the objects. The forward electron transfer time constant from aniline to the excited singlet state of two Rhodamine dyes and subsequent back electron transfer from two dyes to aniline are measured. The experimental results denote that Rh6G presents faster electron transfer rates with aniline in both forward electron transfer and back electron transfer processes. With chemical calculation and qualitative analysis, it is found that the flexible molecular geometry of Rh6G leads to stronger electron coupling with donor solvent and further gives rise to larger electron transfer rates.

关键词： Electron transfer Molecular structure Back electron transfer

Testing of separating catalyst from resid fluid catalytic cracking slurry by 10 mm hydrocyclones

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Journal of Energy and Power Engineering 2007年第1期1卷 63-67页

作者： ZHOU Ping BAI Zhi-shan ZHANG yan-hong yang qiang MA Ji WANG Hua-lin Institute of Pressure Vessel and Process Equipment East China University of Science and Technology Shanghai 200237 China

The paper focuses on removing catalyst solids from oil slurry using 10 mm hydrocyclones, and aims to test the feasibility of the solution. An industrial sidetrack tester of residual oil separation by hydrocyclones was set up in 1.8 Mt/a resid fluid catalytic cracking （RFCC） unit, the effect of pressure drop, separation efficiency and inlet flowrate were studied. It was observed that an increase in feed flowrate will decrease the pressure drop ratio, and with an increase in feed flowrate, separation efficiency increases gradually. Under the condition that feed fiowrate was ranging from 250L/h to 270L/h, the separation efficiency was 45.77%-82.80%, the recovery rate of catalyst solid panicles was increased from 10 20% of electrostatic catalyst separator to 50 80%. Thus, it is feasible to separate the slurry by using the miniature hydrocyclones in RFCC unit.

关键词： hydrocyclone solid-liquid-separation catalytic cracking catalyst separation

利用DSP实现工业机器人关节电机绝对位置测量

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组合机床与自动化加工技术 2017年第9期 103-106页

作者：强艳辉杨侃海军装备研究院北京100161

文章提出了一种机器人关节伺服电机绝对位置获取方法,适用于关节伺服系统由电机与相配套伺服驱动器组成的结构。采用以DSP芯片TMS320F1812为核心的运动控制卡实现并运用如下位置获取策略:系统初始化阶段,运动控制卡接收伺服驱动器传送... 详细信息

文章提出了一种机器人关节伺服电机绝对位置获取方法,适用于关节伺服系统由电机与相配套伺服驱动器组成的结构。采用以DSP芯片TMS320F1812为核心的运动控制卡实现并运用如下位置获取策略:系统初始化阶段,运动控制卡接收伺服驱动器传送的初始绝对位置串行数据;运行阶段,TMS320F1812内嵌QEP解码电路计数增量脉冲获取增量位置,并利用初始绝对位置,计算当前实时绝对位置。针对通过脉冲计数方向标志字判别电机转向存在的缺陷,提出新型转向判别方法及其适用条件,给出了以该判别方法为基础的绝对位置计算方法。文中对运动控制卡位置获取模块的软硬件设计进行了详细介绍,并通过实验证明该位置测量系统能够满足工业机器人的绝对位置的测量需求。

关键词：机器人绝对位置运动控制卡

π-Conjugated Unit-Dependent Optical Properties of Linear Conjugated Oligomers

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Chinese Journal of Chemical Physics 2014年第3期27卷 315-320页

作者： Ning Sui Lu Zou Yun-fei Song Qiu-lin Zhong Ying-hui Wang Xiao-gang Wei Zeng-bin Wang Yu-guang Ma yan-qiang yang Han-zhuang Zhang Femtosecond Laser Laboratory College of Physics Jilin University Changchun 130012 China Quantum Enginerring Center Beingjing Institute of Control Device Beijing 100854 China State Key Laboratory of Supramolecular Structure and Materials Jilin University Changchun 130012 China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 China Department of Physics Harbin Institute of Technique Harbin 150000 China

The optical properties of three linear conjugated oligomers （F-P, F-P-F, and P-F-P-F-P）, where phenothiazine （P） and fluorene （F） groups arrange alternately, are investigated. With the enhancement of the π-conjugated system, their absorption and emission bands both gradually red shift, and their two-photon properties are also improved. Meanwhile, their fluorescence dynamic traces are analyzed with continuous rate distribution model, exhibiting that their decay rates gradually accelerate and the rate distribution width become narrower. The quantum chemical calculation offers their molecular structures and transition mechanism, showing that the enhancement of π-conjugated system should be responsible for tile improvement of two-photon properties.

关键词： Oligomer Z-scan Fluorescence dynamics

Human-induced pluripotent stem cell-derived neural stem cell exosomes improve blood-brain barrier function after intracerebral hemorrhage by activating astrocytes via PI3K/AKT/MCP-1 axis

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Neural Regeneration Research 2025年第2期20卷 518-532页

作者： Conglin Wang Fangyuan Cheng Zhaoli Han Bo yan Pan Liao Zhenyu Yin Xintong Ge Dai Li Rongrong Zhong qiang Liu Fanglian Chen Ping Lei Department of Geriatrics Tianjin Medical University General HospitalTianjinChina School of Medicine Nankai UniversityTianjinChina Tianjin Neurological Institute TianjinChina

Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor ***-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)have shown potential for brain injury repair in central nervous system *** this study,we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying *** results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits,enhanced blood-brain barrier integrity,and reduced leukocyte infiltration in a mouse model of intracerebral ***,hiPSC-NSC-Exos decreased immune cell infiltration,activated astrocytes,and decreased the secretion of inflammatory cytokines like monocyte chemoattractant protein-1,macrophage inflammatory protein-1α,and tumor necrosis factor-αpost-intracerebral hemorrhage,thereby improving the inflammatory *** sequencing indicated that hiPSC-NSC-Exo activated the PI3K/AKT signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion,thereby improving blood-brain barrier *** with the PI3K/AKT inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these *** summary,our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity,in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3K/AKT signaling pathway in astrocytes.

关键词： AKT astrocyte blood-brain barrier cerebral edema exosomes human-induced pluripotent stem cells intracerebral hemorrhage neural stem cells neuroinflammation PI3K

基于累积前景理论的铁路应急预案评估模型研究

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交通运输工程与信息学报 2017年第3期15卷 17-25页

作者：李延来杨强西南交通大学交通运输与物流学院成都610031

为了充分体现决策过程中决策数据的科学性以及决策者的心理行为特征对决策结果的影响,提出基于改进层次分析法与累积前景理论相结合的铁路应急预案评估模型。首先,建立铁路应急环境下的预案评估综合指标体系;其次,基于均衡化的指标体系... 详细信息

为了充分体现决策过程中决策数据的科学性以及决策者的心理行为特征对决策结果的影响,提出基于改进层次分析法与累积前景理论相结合的铁路应急预案评估模型。首先,建立铁路应急环境下的预案评估综合指标体系;其次,基于均衡化的指标体系运用G1法确定各指标权重;最后,建立基于累积前景理论的铁路应急预案评估的科学模型。案例表明,应用该方法对铁路应急预案进行评估是科学有效且可行的。

关键词：铁路应急预案累积前景理论指标体系改进层次分析法预案评估