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Science China Chemistry 2024年第1期67卷 368-373页

作者： Xing-Yu Wang pei xu Wen-Wen Liu Hao-Qiang Jiang Song-Lei Zhu Dong Guo xu Zhu Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy School of PharmacyXuzhou Medical UniversityXuzhou 22100China

Unprecedented divergent synthesis of gem-difluorovinylacetic acid and glutaric acid derivatives fromα-CF_(3)alkenes with formate as the carbonyl source was disclosed.The reaction can undergo selective mono-or triple C-F bond cleavage by simply switching the photocatalyst and hydrogen atom transfer(HAT)catalyst under visible-light-induced conditions at room temperature.Foramte acts as both the C1 source and the reductant through the generation of CO_(2)^(·-)species,which underwent Giese radical addition to electron-deficient alkenes to trigger the consecutive C-F bond cleavage and carboxylation process.

关键词： C-F bond activation defluorocarboxylation carbon dioxide radical anion visible light

Generalized nth-Order Perturbation Method Based on Loop Subdivision Surface Boundary Element Method for Three-Dimensional Broadband Structural Acoustic Uncertainty Analysis

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 2053-2077页

作者： Ruijin Huo Qingxiang pei Xiaohui Yuan Yanming xu College of Architecture and Civil Engineering Xinyang Normal UniversityXinyang464000China Henan Unsaturated Soil and Special Soil Engineering Technology Research Center Xinyang Normal UniversityXinyang464000China Henan International Joint Laboratory of Structural Mechanics and Computational Simulation College of Architecture and Civil EngineeringHuanghuai UniversityZhumadian463000China

In this paper,a generalized nth-order perturbation method based on the isogeometric boundary element method is proposed for the uncertainty analysis of broadband structural acoustic scattering problems.The Burton-Miller method is employed to solve the problem of non-unique solutions that may be encountered in the external acoustic field,and the nth-order discretization formulation of the boundary integral equation is derived.In addition,the computation of loop subdivision surfaces and the subdivision rules are introduced.In order to confirm the effectiveness of the algorithm,the computed results are contrasted and analyzed with the results under Monte Carlo simulations(MCs)through several numerical examples.

关键词： Perturbation method loop subdivision surface isogeometric boundary element method uncertainty analysis

Decohesion of graphene from a uniaxially-stretched substrate:Failure analysis of a frictional adhesive interface

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Friction 2024年第3期12卷 510-521页

作者： Bo PENG Chaochen xu Qingao WANG pei ZHAO Xiqiao FENG Qunyang LI AML Department of Engineering MechanicsTsinghua UniversityBeijing 100084China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Center for X-Mechanics and Institute of Applied Mechanics Zhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and M

Composite structures consisting of two-dimensional(2D)materials deposited on elastic substrates have a wide range of potential applications in flexible electronics.For such devices,robust 2D film/substrate interfacial adhesion is essential for their reliable performance when subjected to external thermal and mechanical loads.To better understand the strength and failure behavior of the 2D film/substrate interfaces,two types of graphene/polymer samples with distinct interfacial adhesion properties are fabricated and tested by uniaxially stretching the substrates.Depending on the interfacial adhesion,two drastically different debonding rates are observed,i.e.,rapid snap-through debonding and more progressive crack propagation.Motivated by the experimental observation,we propose an improved shear-lag model with a trapezoidal-shaped cohesive zone to derive an analytical solution for the decohesion behavior.The theoretical model reveals that the decohesion behavior of the frictional adhesive interface is governed by three dimensionless parameters.Particularly,the dimensionless length of the film essentially determines the decohesion rate;while the other two parameters affect the critical substrate strain to initiate debonding.By fitting the experimental data with the theoretical model,the intrinsic adhesion properties of the two samples are obtained with physically meaningful values.This work offers an analytical solution to describing the decohesion behavior of general thin film/substrate systems with a frictional adhesive interface,which is beneficial for characterizing and optimizing the mechanical properties of various thin film/polymer devices.

关键词： film/substrate systems adhesion frictional sliding interface decohesion cohesive-zone model

Role of temperature in tribolayers in fretting wear ofγ-TiAl alloy

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Friction 2024年第5期12卷 939-953页

作者： Yulei YANG Hongfei SHANG Huiping pei Jimin xu Yi LIANG Minghui PAN School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing100084China Institute of Tribology Hefei University of TechnologyHefei230009China

The formation of tribolayers may play significant influences on fretting wear.At elevated temperature,the adhesion among wear debris and the increased diffusion rate facilitate the formation of tribolayers.However,the intensification of oxidation at elevated temperature and the low diffusion rate in oxides may play an adverse role.The present study aims to investigate the role of temperature in tribolayers in fretting wear using aγ-TiAl alloy.Scanning electron microscope,energy dispersive spectrometer,Raman spectrometer,transmission electron microscope and nanoindentation were utilized to investigate the wear debris,tribolayers,and wear scars.The fretting tests showed that,compared with that at room temperature(RT)and 350℃,significant reduction in wear rate and decrease in the fluctuation of friction coefficient occurred at 550 and 750℃.It was further revealed that when temperature raised from room temperature(RT)to 750℃,the oxidation of the wear debris increased slightly and the diffusion coefficients increased prominently,which facilities the formation of well tribo-sintered tribolayers.The well tribo-sintered tribolayers presented homogenous structure,nanocrystalline grains with excellent mechanical properties,and resulted in the improvement in the fretting wear resistance of theγ-TiAl alloy at 550 and 750℃.

关键词： tribolayer temperature fretting wear γ-TiAl alloy

Charge-asymmetry Fe_(1)Cu single-atom alloy catalyst for efficient oxygen reduction reaction

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Nano Research 2024年第6期17卷 4702-4710页

作者： xudong Niu Jian Wei Dongyao xu Jiajing pei Rui Sui School of Chemical&Environmental Engineering China University of Mining and TechnologyBeijing 100083China Institute of Water Ecology and Environment Chinese Research Academy of Environmental SciencesBeijing 100083China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084China

The development of high-efficient and low-cost oxygen reduction reaction(ORR)electrocatalysts is crucial for the practical applications of metal-air batteries.One promising way is to develop Fe single-atom catalysts.However,the single active center and inherent electronic structure of Fe single-atom catalysts lead to the undesirable adsorption of multiple ORR intermediates.Herein,a charge-asymmetry single-atom alloy(SAA)catalyst with Fe-Cu dual sites supported on nitrogen-doped carbon nanosheet(Fe_(1)Cu SAA/NC)was constructed.Various characterizations manifest the existence of electron interaction between Fe and Cu in Fe_(1)Cu SAA/NC,which facilitates the adsorption of ORR intermediate for fast kinetics.Consequently,the charge-asymmetry Fe_(1)Cu SAA/NC exhibits much faster ORR kinetics with a half-wave potential of 0.917 V vs.reversible hydrogen electrode(RHE),outperforming its counterparts in the references.Furthermore,Fe_(1)Cu SAA/NC still maintains a high half-wave potential with only a drop of 5 mV after 5000 cycles,indicating excellent stability.This work provides a new strategy to design highly active and non-noble metal ORR electrocatalysts,which hold great potential for various catalytic applications.

关键词： Fe_(1)Cu single-atom alloy(SAA) electrocatalysis oxygen reduction reaction charge-asymmetry

Nd:YAG water mist laser treatment for giant gestational gingival tumor: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1974-1979页

作者： Hong-Yu Chen Jun-Ji xu Xiu-Lin Chang pei Wu Department of Stomatology Women and Children's Hospital Affiliated to Ningbo UniversityNingbo 315012Zhejiang ProvinceChina

BACKGROUND This case of gestational gingival tumor is huge and extremely rare in clinical practice.As the growth location of this gingival tumor is in the upper anterior tooth area,it seriously affects the pregnant woman's speech and food,causing great pain to the patient.The use of Nd:YGA water mist laser to remove the gingival tumor resulted in minimal intraoperative bleeding,minimal adverse reactions,and good postoperative healing,which is worthy of clinical promotion and application.CASE SUMMARY The patient,a pregnant woman,reported a large lump in her mouth on the first day of postpartum treatment.Based on medical history and clinical examination,the diagnosis was diagnosed as gestational gingival tumor.Postoperative pathological biopsy also confirmed this diagnosis.The use of Nd:YAG water mist laser to remove the tumor resulted in minimal intraoperative bleeding,clear surgical field of view,short surgical time,and good postoperative healing.CONCLUSION In comparison to traditional surgery,Nd:YAG water mist laser surgery is minimally invasive,minimizes cell damage,reduces bleeding,ensures a clear field of vision,and virtually eliminates postoperative edema,carbonization,and the risk of cross infection.It has unique advantages in oral soft tissue surgery for pregnant patients.Therefore,the clinical application of Nd:YAG water mist laser for the treatment of gestational gingival tumors is an ideal choice.

关键词： Gestational gingival tumor Nd:YAG water mist laser Granulomatous gingival tumor Minimally invasive dentistry Pregnancy related diseases Oral soft tissue surgery Case report

Nrf2-mediated ferroptosis of spermatogenic cells involved in male reproductive toxicity induced by polystyrene nanoplastics in mice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 307-323页

作者： xufeng FU Hang HAN Hong YANG Bo xu Wenjie DAI Ling LIU Tiantian HE Xing DU Xiuying pei Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education School of Basic Medical SciencesNingxia Medical UniversityYinchuan 750004China Key Laboratory of Reproduction and Genetics in Ningxia Ningxia Medical UniversityYinchuan 750004China

Microplastics(MPs)and nanoplastics(NPs)have become hazardous materials due to the massive amount of plastic waste and disposable masks,but their specific health effects remain uncertain.In this study,fluorescence-labeled polystyrene NPs(PS-NPs)were injected into the circulatory systems of mice to determine the distribution and potential toxic effects of NPs in vivo.Interestingly,whole-body imaging found that PS-NPs accumulated in the testes of mice.Therefore,the toxic effects of PS-NPs on the reproduction systems and the spermatocytes cell line of male mice,and their mechanisms,were investigated.After oral exposure to PS-NPs,their spermatogenesis was affected and the spermatogenic cells were damaged.The spermatocyte cell line GC-2 was exposed to PS-NPs and analyzed using RNA sequencing(RNA-seq)to determine the toxic mechanisms;a ferroptosis pathway was found after PS-NP exposure.The phenomena and indicators of ferroptosis were then determined and verified by ferroptosis inhibitor ferrostatin-1(Fer-1),and it was also found that nuclear factor erythroid 2-related factor 2(Nrf2)played an important role in spermatogenic cell ferroptosis induced by PS-NPs.Finally,it was confirmed in vivo that this mechanism of Nrf2 played a protective role in PS-NPs-induced male reproductive toxicity.This study demonstrated that PS-NPs induce male reproductive dysfunction in mice by causing spermatogenic cell ferroptosis dependent on Nrf2.

关键词： Polvstyrene nanoplastics(PS-NPs) Reproductive toxicity Ferroptosis Nuclear factor ervthroid 2-related factor 2(Nrf2)

Dynamic asymmetric mechanical responsive carbon nanotube fiber for ionic logic gate

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Chinese Chemical Letters 2024年第6期35卷 249-253页

作者： pei Cao Yilan Wang Lejian Yu Miao Wang Liming Zhao xu Hou State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China The Higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Department of BiomaterialsResearch Center of Biomedical Engineering of XiamenCollege of MaterialsXiamen UniversityXiamen 361005China Key Laboratory of Multifunctional Nanomaterials and Smart Systems Advanced Materials DivisionSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Institute of Artificial Intelligence Xiamen UniversityXiamen 361005China Department of Physics Research Institute for Biomimetics and Soft MatterFujian Provincial Key Laboratory for Soft Functional Materials ResearchJiujiang Research InstituteCollege of Physical Science and TechnologyXiamen UniversityXiamen 361005China Engineering Research Center of Electrochemical Technologies of Ministry of Education Xiamen UniversityXiamen 361005China

Inspired by biological ion channels,numerous artificial asymmetric ion channels have been synthesized to facilitate the fabrication of ionic circuits.Nevertheless,the creation of biomimetic asymmetric ion channels necessitates expensive scientific apparatus and intricate material processing procedures,which constrains its advancement within the realm of ionic devices.In this study,we have devised dynamic asymmetric ion channels with mechanical responsiveness by combining polymers of varying elastic modulus along the longitudinal axis of carbon nanotube fiber(CNTF).The ion rectification can be modulated via the disparate response of CNTF-based ion channels to mechanical stress.We have effectively employed these asymmetric ion channels with mechanical sensitivity in the design of a logic gate device,achieving logic operations such as“AND”and“OR”.The conception of these dynamic asymmetric ion channels with mechanical sensitivity offers a straightforward,cost-effective,and versatile approach for generating ion channels,highlighting their potential application in intricate,highly integrated ionic circuits.

关键词： Carbon nanotubes fibers Mechanical response Rectification effect Ionic logic gate

Protective Effects of Danmu Extract Syrup on Acute Lung Injury Induced by Lipopolysaccharide in Mice through Endothelial Barrier Repair

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Chinese Journal of Integrative Medicine 2024年第3期30卷 243-250页

作者： xu Han xu Si-cong LI Li-yan WU Yu-huang TAN Yin-feng CHEN Long LIU pei LIANG Chang-fu HE Xiao-ning LI Yong-hui Hainan Provincial Key Lab of Research&Development on Tropic Herbs Hainan Medical UniversityHaikou571199China Department of Stomatology the Second Affiliated Hospital of Hainan Medical UniversityHaikou571199China

Objective:To investigate the effects of Danmu Extract Syrup(DMS) on lipopolysaccharide(LPS)-induced acute lung injury(ALI) in mice and explore the mechanism.Methods:Seventy-two male Balb/C mice were randomly divided into 6 groups according to a random number table(n=12),including control(normal saline),LPS(5 mg/kg),LPS+DMS 2.5 mL/kg,LPS+DMS 5 mL/kg,LPS+DMS 10 mL/kg,and LPS+Dexamethasone(DXM,5 mg/kg) groups.After pretreatment with DMS and DXM,the ALI mice model was induced by LPS,and the bronchoalveolar lavage fluid(BALF) were collected to determine protein concentration,cell counts and inflammatory cytokines.The lung tissues of mice were stained with hematoxylin-eosin,and the wet/dry weight ratio(W/D) of lung tissue was calculated.The levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and IL-1βin BALF of mice were detected by enzyme linked immunosorbent assay.The expression levels of Claudin-5,vascular endothelial(VE)-cadherin,vascular endothelial growth factor(VEGF),phospho-protein kinase B(p-Akt) and Akt were detected by Western blot analysis.Results:DMS pre-treatment significantly ameliorated lung histopathological changes.Compared with the LPS group,the W/D ratio and protein contents in BALF were obviously reduced after DMS pretreatment(P<0.05 or P<0.01).The number of cells in BALF and myeloperoxidase(MPO) activity decreased significantly after DMS pretreatment(P<0.05 or P<0.01).DMS pre-treatment decreased the levels of TNF-α,IL-6 and IL-1β(P<0.01).Meanwhile,DMS activated the phosphoinositide 3-kinase/protein kinase B(PI3K/Akt) pathway and reversed the expressions of Claudin-5,VE-cadherin and VEGF(P<0.01).Conclusions:DMS attenuated LPS-induced ALI in mice through repairing endothelial barrier.It might be a potential therapeutic drug for LPS-induced lung injury.

关键词： Danmu Extract Syrup acute lung injury inflammatory factors vascular endothelial growth factor phosphoinositide 3-kinase/protein kinase B Chinese medicine Nauclea officinalis

Removal of rubidium from brine by an integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide

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Chinese Journal of Chemical Engineering 2024年第5期69卷 112-121页

作者： Huanxi xu peihua Lin pei-Jun Liu Hai-Gang Liu Hui-Bin Guo Chao-Xiang Wu Ming Fang xu Zhang Guan-Ping Jin Anhui Province Engineering Research Center of Flexible and Intelligent Materials School of Chemistry and Chemical EngineeringHefei University of TechnologyHefei 230009China Chemical Design and Research Institute Co. LTD of Qinghai ProvinceQinghai Engineering and Technology Research Center of Fine ChemicalXining 810008China

A novel integrated film of sulfonated polysulfone/graphene/potassium copper ferricyanide(KCuFC/SPSG)was used for selectively extracting rubidium ion(Rb^(+))from brine.To form KCuFC/SPSG,the precursor film of sulfonated polysulfone/graphene(SPSG)was synthesized by phase conversion process,which was alternately immersed in 0.1 mol·L^(-1)CuSO_(4)/K_(4)[Fe(CN)_(6)]by in-situ adsorption coupled co-precipitation method.Various data such as nuclear magnetic resonance spectrometer,Fourier transform infrared spectroscope,X-ray photoelectron spectroscope,X-ray diffraction,scanning electron microscope,and energy dispersive spectroscopy all verified that abundant KCuFC were uniformly located on the film.The resulting KCuFC/SPSG was used in film separation system.As the solution was fed into the system,the Rb^(+)could be selectively adsorption by KCuFC/SPSG.After the saturation adsorption,0.5 mol·L^(-1)NH_(4)Cl/HCl was fed into the film cell,Rb^(+)could be quickly desorbed by ion-exchange between Rb^(+)and NH_(4)^(+)in the lattice of KCuFC.The purpose of separating and recovering Rb^(+)from the brine can be achieved after the repeated operation.The effects of pH,adsorption time,and interferential ions on the adsorption capacity of Rb^(+)were investigated by batch experiments.The adsorption behavior fits the pseudo-second order kinetic process,while KCuFC has a higher adsorption capacity(Langmuir maximum sorption 165.4 mg·g^(-1)).In addition,KCuFC/SPSG shows excellent selectivity for Rb^(+)even in complex brine systems.KCuFC/SPSG could maintain 93.5%extraction efficiency after five adsorption/desorption cycles.

关键词： Rubidium extraction Potassium copper ferricyanide Sulfonated polysulfone Graphene oxide Adsorption