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Flow Control Effect of Spanwise Distributed Pulsed Arc Discharge Plasma Actuation on Supersonic Compressor Cascade Flow

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Journal of Thermal Science 2022年第5期31卷 1723-1733页

作者： SHENG Jiaming wu yun zhang Haideng WANG Yizhou TANG Mengxiao Science and Technology on Plasma Dynamic Laboratory Air Force Engineering UniversityXi’an710038China Institute of Aero-engine School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an710049China

To achieve efficient control of supersonic compressor cascade flow,a type of spanwise distributed pulsed arc discharge plasma actuation(PADPA)was designed.To simulate the influences of PADPA on the flow field,a phenomenological model was established.Then,the flow control effects of PADPA on supersonic compressor cascade flow were researched numerically.The results show that under low static pressure ratio condition,the compressive wave induced by PADPA reduced the intensity of the passage shock wave,which eventually reduced shock wave loss.It was also found that PADPA produced an adverse pressure gradient(pre-compression effect)around the actuation location,which reduced the strength of the high adverse pressure gradient induced by the passage shock wave.The airflow on both sides of the actuation location was accelerated by PADPA owing to the spanwise distributed layout.Thus,it improved the ability of the boundary layer to resist the effect of the adverse pressure gradient and reduced the separation zone.Consequently,the total pressure loss was reduced by 6.8%.Under high pressure ratio condition,the effect of PADPA on the suction side controlling the large separation of the boundary layer was insignificant.The total pressure loss also increased slightly.

关键词： plasma flow control supersonic cascade shock wave/boundary layer interaction numerical simulation

Theoretical insight into the activity and selectivity in palladium/Ming-Phos-catalyzed three-component asymmetric synthesis of gem-diarylmethine silanes

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Science China Chemistry 2023年第10期66卷 2817-2827页

作者： Bo Xiao Tian-Yu Sun Junliang zhang yun-Dong wu State Key Laboratory of Chemical Oncogenomics Key Laboratory of Computational Chemistry and Drug DesignSchool of Chemical Biology and BiotechnologyPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China Department of Chemistry Fudan UniversityShanghai 200438China College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China

Recently,a three-component coupling reaction for efficient construction of gem-diarylmethine silanes was developed,utilizing a Pd-Ming-Phos catalyst.To explore the underlying mechanism governing this intriguing reaction,we have conducted comprehensive density functional theory(DFT)computations(M06-L/SDD/6-311++G(d,p)/SMD//B3LYP-D3/lanl2dz/6-31G(d,p)).DFT calculations reveal that the oxidative addition of Ar Br to Pd(0)is the rate-determining step,and the carbenation process of Ph CHN_(2)to Pd(Ⅱ)is the enantioselectivity-determining step.Moreover,the Ming-Phos ligand exhibits a self-adaptive nature,allowing it to dynamically adapt its coordination patterns with the metal center in different elementary steps,thereby enhancing the overall reactivity.The enantioselectivity is determined by both the trans effect and the side-arm effect of the ligand.This mechanism nicely explains why TY-Phos with P-tBu_(2)instead of the Ming-Phos with P-Ph2results in poor reactivity and much reduced enantioselectivity.This study not only provides deeper insights into the functioning principles of Sad Phos ligands but also offers valuable guidance for future ligand modifications and optimizations.

关键词： self-adaptive effect side-arm effect Ming-Phos ligand gem-diarylmethine silanes DFT study

Tau-mediated Neurodegeneration and Potential Implications in Diagnosis and Treatment of Alzheimer＇s Disease

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Chinese Medical Journal 2017年第24期130卷 2978-2990页

作者： Xi-Lin wu Juan Pina-Crespo Yun-Wu Zhang Xiao-Chun Chen Hua-Xi Xu Neuroscience Initiative Neuroscience and Aging Research Center Sanford Burnham Prebys Medical Discovery Institute La Jolla CA 92037 USA Department of Neurology Fujian Institute of Geriatrics Fujian Medical University Union Hospital Fujian Key Laboratory of Molecular Neurology Fujian Medical University Fuzhou Fujian 350001 China Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research Institute of Neuroscience College of Medicine Xiamen University XiamenFujian 361102 China

Objective：To review recent research advances on tau,a major player in Alzheimer＇s disease （AD） pathogenesis,a biomarker for AD onset,and potential target for AD therapy.Data Sources：This review was based on a comprehensive search using online literature databases,including PubMed,Web of Science,and Google Scholar.Study Selection：Literature search was based on the following keywords：Alzheimer＇s disease,tau protein,biomarker,cerebrospinal fluid （CSF）,therapeutics,plasma,imaging,propagation,spreading,seeding,prion,conformational templating,and posttranslational modification.Relevant articles were carefully reviewed,with no exclusions applied to study design and publication type.Results：Amyloid plaques enriched with extracellular amyloid beta （Aβ） and intracellular neurofibrillary tangles comprised of hyperphosphorylated tau proteins are the two main pathological hallmarks ofAD.Although the Aβ hypothesis has dominated AD research for many years,clinical Aβ-targeting strategies have consistently failed to effectively treat AD or prevent AD onset.The research focus in AD has recently shifted to the role oftau in AD.In addition to phosphorylation,tau is acetylated and proteolytically cleaved,which also contribute to its physiological and pathological functions.Emerging evidence characterizing pathological tau propagation and spreading provides new avenues for research into the molecular and cellular mechanisms underlying AD pathogenesis.Techniques to detect tau at minute levels in CSF and blood have been developed,and improved tracers have facilitated tau imaging in the brain.These advances have potential to accurately determine tau levels at early diagnostic stages in AD.Given that tau is a potential therapeutic target,anti-tau immunotherapy may potentially be a viable treatment strategy in AD intervention.Conclusion：Detecting changes in tau and targeting tau pathology represent a promising lead in the diagnosis and treatment of AD.

关键词： Alzheimer＇s Disease Biomarker lmmunotherapy Tau Imaging Tau Protein Transcellular Propagation

Advances in doping strategies for sodium transition metal oxides cathodes:A review

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Frontiers in Energy 2024年第2期18卷 141-159页

作者： Zhijing zhang Haoze zhang Yaopeng wu Wei YAN Jiujun zhang yun ZHENG Lanting QIAN Department of Chemical Engineering Waterloo Institute of NanotechnologyUniversity of WaterlooWaterloo ON N2L 3G1Canada School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China Institute of New Energy Materials Science and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China

The electrochemistry of cathode materials for sodium-ion batteries differs significantly from lithium-ion batteries and offers distinct advantages.Overall,the progress of commercializing sodium-ion batteries is currently impeded by the inherent inefficiencies exhibited by these cathode materials,which include insufficient conductivity,slow kinetics,and substantial volume changes throughout the process of intercalation and deintercalation cycles.Consequently,numerous methodologies have been utilized to tackle these challenges,encompassing structural modulation,surface modification,and elemental doping.This paper aims to highlight fundamental principles and strategies for the development of sodium transition metal oxide cathodes.Specifically,it emphasizes the role of various elemental doping techniques in initiating anionic redox reactions,improving cathode stability,and enhancing the operational voltage of these cathodes,aiming to provide readers with novel perspectives on the design of sodium metal oxide cathodes through the doping approach,as well as address the current obstacles that can be overcome/alleviated through these dopant strategies.

关键词： sodium-ion batteries transition metal cathode doping strategy

Long-term potentiation-based screening identifies neuronal PYGM as a synaptic plasticity regulator participating in Alzheimer's disease

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动物学研究(英文) 2023年第5期44卷 867-881页

作者： Ting Wang yun-Qiang Zhou Yong Wang Liang zhang Xiang Zhu Xiu-Yan Wang Jing-Hui Wang Lin-Kun Han Jian Meng Xian zhang Hong Luo Qi-Lin Ma Zhan-Xiang Wang Yun-Wu Zhang Xiamen Key Laboratory of Brain Center The First Affiliated Hospital of Xiamen Universityand Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging ResearchInstitute of NeuroscienceSchool of MedicineXiamen UniversityXiamenFujian 361102China Fujian Provincial Clinical Research Center for Brain Diseases The First Affiliated Hospital of Xiamen UniversityXiamenFujian 361003China

Synaptic dysfunction is an important pathological hallmark and cause of Alzheimer's disease(AD).High-frequency stimulation(HFS)-induced long-term potentiation(LTP)has been widely used to study synaptic plasticity,with impaired LTP found to be associated with AD.However,the exact molecular mechanism underlying synaptic plasticity has yet to be completely elucidated.Whether genes regulating synaptic plasticity are altered in AD and contribute to disease onset also remains unclear.Herein,we induced LTP in the hippocampal CA1 region of wildtype(WT)and AD model mice by administering HFS to the CA3 region and then studied transcriptome changes in the CA1 region.We identified 89 genes that may participate in normal synaptic plasticity by screening HFS-induced differentially expressed genes(DEGs)in mice with normal LTP,and 43 genes that may contribute to synaptic dysfunction in AD by comparing HFS-induced DEGs in mice with normal LTP and AD mice with impaired LTP.We further refined the 43 genes down to 14 by screening for genes with altered expression in pathological-stage AD mice without HFS induction.Among them,we found that the expression of Pygm,which catabolizes glycogen,was also decreased in AD patients.We further demonstrated that down-regulation of PYGM in neurons impaired synaptic plasticity and cognition in WT mice,while its overexpression attenuated synaptic dysfunction and cognitive deficits in AD mice.Moreover,we showed that PYGM directly regulated energy generation in neurons.Our study not only indicates that PYGM-mediated energy production in neurons plays an important role in synaptic function,but also provides a novel LTP-based strategy to systematically identify genes regulating synaptic plasticity under physiological and pathological conditions.

关键词： Alzheimer's disease High-frequency stimulation Long-term potentiation PYGM Synaptic plasticity Transcriptome

Reaction kinetics and internal diffusion of Zhundong char gasification with CO_(2)

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Frontiers of Chemical Science and Engineering 2021年第2期15卷 373-383页

作者： yun Liu Jiangyuan Qu Xuehui wu Kai zhang Yuan zhang Beijing Key Laboratory of Emission Surveillance and Control for Thermal Power Generation North China Electric Power UniversityBeijing 102206China College of Metallurgy&Energy North China University of Science and TechnologyTangshan 063009China

Mass transfer usually affects the rate of chemical reactions in coal.The effect of internal diffusion on char gasification with CO_(2) in the temperature range from 1123 K to 1273 K was investigated via thermo-gravimetric analysis and assessment of char morphology features.The results revealed that the effect of internal diffusion on the initial reaction rate was more significant with an increase of particle size,due to the concentration gradient of the gasification agent within the solid particles.In the early stage of gasification,the generation of new micropores and the opening of closed pores led to an increase in specific surface area.As the reaction proceeded,the openings were gradually expanded and the specific surface area continued to increase.However,with further reaction,disappearance of edge pores,melting and collapse of the pore structure led to a decrease in specific surface area.The intrinsic activation energy and reaction order based on the nth-order model were 157.67 kJ∙mol^(−1) and 0.36,respectively.Thus,temperature zones corresponding to chemical reaction and diffusion control were identified.Moreover,the calculated effectiveness factor provided a quantitative estimation of internal diffusion in the initial stage.

关键词： coal char CO_(2)gasification internal diffusion pore evolution

Ihog proteins contribute to integrin-mediated focal adhesions

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Science China(Life Sciences) 2023年第2期66卷 366-375页

作者： yun Qi Han Liu Kang zhang Yihui wu Chenghao Shen Xinhua Lin The State Key Laboratory of Genetic Engineering Institute of GeneticsSchool of Life SciencesFudan UniversityShanghai 200433China The State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100864China Current Address:Human Phenome Institute Fudan UniversityShanghai 200433China

Integrin expression forms focal adhesions, but how this process is physiologically regulated is unclear. Ihog proteins are evolutionarily conserved, playing roles in Hedgehog signaling and serving as trans-homophilic adhesion molecules to mediate cell-cell interactions. Whether these proteins are also engaged in other cell adhesion processes remains unknown. Here, we report that Drosophila Ihog proteins function in the integrin-mediated adhesions. Removal of Ihog proteins causes blister and spheroidal muscle in wings and embryos, respectively. We demonstrate that Ihog proteins interact with integrin via the extracellular portion and that their removal perturbs integrin distribution. Finally, we show that Boc, a mammalian Ihog protein,rescues the embryonic defects caused by removing its Drosophila homologs. We thus propose that Ihog proteins contribute to integrin-mediated focal adhesions.

关键词： integrin focal adhesion Ihog/Boi Drosophila

In-situ formation of Li_(0.5)Mn_(0.5)O coating layer through defect controlling for high performance Li-rich manganese-based cathode material

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Journal of Energy Chemistry 2022年第8期31卷 384-391,I0010页

作者： Aipeng Zhu Qin Wang Yin zhang Yueyin zhang Xiaogang He Kaipeng wu Hao wu Qian Wang Wenlong Cai yun zhang Department of Advanced Energy Materials College of Materials Science and EngineeringSichuan UniversityChengdu 610064SichuanChina Engineering Research Center of Alternative Energy Materials&Devices Ministry of EducationSichuan UniversityChengdu 610064SichuanChina

Li-rich layered oxide of Li_(1.2)Mn_(0.6)Ni_(0.2)O_(2)(LMNO)with a considerable specific capacity and higher voltage is regarded as a kind of promising cathode material.However,it suffers from transition metal ion dissolution and oxygen escape that leads to rapid capacity decay.In addition,the poor lithium-ion diffusion kinetics gives rise to unsatisfied rate performance.Herein,a stable layer of Li_(0.5)Mn_(0.5)O(LMO)out of LMNO is in-situ constructed through acetic passivation and following calcination process.The generated defect structure in the composite material exhibits fast ion diffusion kinetics and the produced LMO layer can stabilize the substructure,resulting in elevated cycling stability and rate performance.In specific,the LMNO@LMO material exhibits a high initial coulombic efficiency of 80.3%and remarkable capacity retention of 80.7%after 200 cycles at 1 C.Besides,the composite material reveals prominent rate performance that delivers discharge capacities of 158 and 131 m Ah g^(-1) at 5 and 10 C,respectively.At last,this study presents a new approach to optimizing the Li-rich cathode materials.

关键词： Defect Interfacial stability Li_(0.5)Mn_(0.5)O Li-rich layered oxides Lithium-ion batteries

Mapping winter rapeseed in South China using Sentinel-2 data based on a novel separability index

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Journal of Integrative Agriculture 2023年第6期22卷 1645-1657页

作者： TAO Jian-bin zhang Xin-yue wu Qi-fan WANG yun Key Laboratory for Geographical Process Analysis&Simulation of Hubei Province/School of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079P.R.China

Large-scale crop mapping using remote sensing data is of great significance for agricultural production, food security and the sustainable development of human societies. Winter rapeseed is an important oil crop in China that is mainly distributed in the Yangtze River Valley. Traditional winter rapeseed mapping practices are insufficient since they only use the spectral characteristics during the critical phenological period of winter rapeseed, which are usually limited to a small region and cannot meet the needs of large-scale applications. In this study, a novel phenology-based winter rapeseed index(PWRI) was proposed to map winter rapeseed in the Yangtze River Valley. PWRI expands the date window for distinguishing winter rapeseed and winter wheat, and it has good separability throughout the flowering period of winter rapeseed. PWRI also improves the separability of winter rapeseed and winter wheat, which traditionally have been two easily confused winter crops. A PWRI-based method was applied to the Middle Reaches of the Yangtze River Valley to map winter rapeseed on the Google Earth Engine platform. Time series composited Sentinel-2 data were used to map winter rapeseed with 10 m resolution. The mapping achieved a good result with overall accuracy and kappa coefficients exceeding 92% and 0.85, respectively. The PWRI-based method provides a new solution for high spatial resolution winter rapeseed mapping at a large scale.

关键词： phenology-based winter rapeseed index winter rapeseed mapping Sentinel-2 Google Earth Engine