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Acta Mechanica Solida Sinica 2024年第2期37卷 271-284页

作者： Hanxing Zhao Pengyu Cao Fengfeng Li xin Lan Liwu liu Yanju liu Jinsong Leng Centre of Composite Materials and Structures Harbin Institute of Technology(HIT)Harbin150080China Department of Astronautical Science and Mechanics Harbin Institute of Technology(HIT)Harbin150001China

The mismatch in thermal expansion coefficients between the fiber-rich and resin-rich regions of a shape memory polymer composite(SMPC)laminate,along with the residual strain during SMPC fabrication,results in buckling deformation of the inhomogeneous *** paper presents a macroscopic model for buckling of an inhomogeneous SMPC laminate under initial biaxial *** linear and nonlinear buckling analyses are carried out using the energy *** influences of prestrain biaxiality,temperature,and ply angle on the buckling wavelength,critical buckling prestrain,and buckling amplitude are *** results demonstrate that the critical buckling wavelength of the SMPC laminate is independent of the prestrain,while the amplitude is almost independent of *** addition,the optimal fiber stacking configuration with the maximum critical buckling prestrains of inhomogeneous SMPC laminates is determined by a genetic algorithm.

关键词： Shape memory polymer composite Buckling behavior Inhomogeneous laminate Biaxial prestrains

Investigation on photonic crystal nanobeam cavity based on mixed diamond–circular holes

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Nanotechnology and Precision Engineering 2024年第1期7卷 63-70页

作者： Jingtong Bin kerui Feng Shang Ma ke liu Yong Cheng Jing Chen Qifa liu College of Telecommunication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210003China State key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong UniversityShanghai 200240China

A photonic crystal nanobeam cavity(M-PCNC)with a structure incorporating a mixture of diamond-shaped and circular air holes is *** performance of the cavity is simulated and studied *** theﬁnite-difference time-domain method,the parameters of the M-PCNC,including cavity thickness and width,lattice constant,and radii and numbers of holes,are optimized,with the quality factor Q and mode volume Vm as performance *** modulation of the lattice constant and hole radius enable the proposed M-PCNC to realize outstanding *** optimized cavity possesses a high quality factor Q 1.45105 and an ultra-small mode=×volume Vm 0.01(λ/n)[Zeng et al.,Opt Lett 2023:48;3981–3984]in the telecommunications wavelength *** can be progres-=sively squeezed in both the propagation direction and the perpendicular in-plane direction by a series of interlocked anti-slots and slots in the diamond-shaped hole ***,the energy can be conﬁned within a small mode volume to achieve an ultra-high Q/Vm ratio.

关键词： Photonic crystal nanobeam cavity Mixed diamond–circular holes Slots and anti-slots FDTD simulation Quality factor Mode volume

Flavor mixing and solution structures in Dyson–Schwinger equations for a two-flavor system

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Communications in Theoretical Physics 2024年第10期76卷 64-77页

作者： Xue-ao Chao Yu-xin liu Department of Physics and State key Laboratory of Nuclear Physics and Technology Peking University Collaborative Innovation Center of Quantum Matter Center for High Energy Physics Peking University

We solved the Dyson–Schwinger(DS) equations for a two-flavor system with symmetry to study its flavor mixing effects. Initially, we employed the point interaction model and bare vertex approximation to reveal the structure of the solutions. Using the point interaction model, the DS equations can be solved analytically, and we found that these solutions can be classified into three groups, each forming an ellipse. These solutions exhibit SO(2) symmetry, while the original SU(2)symmetry at the Lagrangian level is dynamically broken to SO(2), corresponding to the emergence of flavor mixing effects. However, this flavor mixing effect does not manifest in the final physical *** utilizing the system's SO(2) symmetry, we can diagonalize the propagators of the DS equations,eliminating the flavor mixing effect but causing the originally degenerate masses at the Lagrangian level to split. These mass eigenstates have identical quantum numbers but different masses. If we can correspond these to quark particles of different generations, we can explain why the three generations of quarks have different masses and obtain the corresponding quark mass spectrum. Finally, we provide the corresponding numerical results using a more realistic interaction model.

关键词： dynamic symmetry breaking Dyson-Schwinger equation flavor change mass splitting

Layered niobium carbide enabling excellent kinetics and cycling stability of Li-Mg-B-H hydrogen storage material Layered niobium carbide enabling excellent kinetics

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Rare Metals 2024年第3期43卷 1153-1166页

作者： Li-Wen Lu Hui Luo Guang-Xu Li Yun Li xin-Hua Wang Cun-ke Huang Zhi-QiangLan Wen-Zheng Zhou Jin Guo Mohammad Ismail Hai-Zhen liu Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Colleges and Universities Key Laboratory of Blue Energy and Systems IntegrationSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China State key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures Nanning530004China School of Mechanical and Electrical Engineering Quzhou College of TechnologyQuzhou324000China Department of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Faculty of Ocean Engineering Technology and Informatics Universiti Malaysia Terengganu21030Kuala NerusTerengganuMalaysia key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin300071China

The Li-Mg-B-H composite(2LiBH_(4)+MgH_(2))has a high capacity of 11.4 wt%as a hydrogen storage ***,the slow kinetics and poor cycling stability severely restrict its practical *** this work,a layered Nb_(2)C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the Li-Mg-B-H *** milled 2LiH+MgB_(2)composites were initially hydrogenated to obtain the 2LiBH_(4)+MgH_(2)*** 2LiBH_(4)+MgH_(2)+5wt%Nb_(2)C can release 9.0 wt%H_(2)in 30 min at 400℃,while it is only 2.7 wt%for the undoped 2LiBH_(4)+MgH_(2).The dehydrogenation activation energies of MgH_(2)and LiBH_(4)are 123 and 154 kJ·mol^(-1)respectively for the 5 wt%Nb_(2)C-doped composite,lower than the undoped composite(164 and 165 kJ·mol^(-1)).The 2LiBH_(4)+MgH_(2)+5 wt%Nb_(2)C possesses excellent cycling stability,with the reversible capacity only slightly reduced from 9.4 wt%for the 1st cycle to 9.3 wt%for the 20th ***_(2)C keeps stable in the composite and acts as an efficient catalyst for the Li-Mg-B-H *** is believed that both the layered structure and the active Nb element contribu te to the enhanced hydrogen storage performances of the Li-Mg-B-H *** work confirms that the Nb_(2)C MXene with layered stru cture has a significant enhancing impact on the Li-Mg-B-H hydrogen storage materials,which is different from the bulk NbC.

关键词： Hydrogen storage Lithium borohydride Magnesium hydride Nb_(2)C MXene

Evolution and function of residual solvent in polymer-Li_2B_(12)H_(12) composite solid electrolyte

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Rare Metals 2024年第8期43卷 3748-3757页

作者： Xiang-Yang Ye ke-Pan Bao Sai-Nan Luo xin Li Tai-Qiang Chen Shui-xin Xia Tao Yuan Yue-Peng Pang Shi-You Zheng School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Department of Materials Science and Engineering National University of SingaporeSingapore 119077Singapore

Composite solid electrolytes(CSEs) containing polymer matrices and inorganic fillers hold promise for the next generation of solid-state ***,the role of residual solvents in CSEs remains *** study investigated the evolution and function of the residual solvent in a polymer-Li_2B_(12)H_(12) CSE.A partial reaction occurred between Li_2B_(12)H_(12) and solvent N,N-dimethylformamide(DMF),which produced dimethylaminomethanol(DMAM) in the *** functional theory calculations have revealed that DMA M forms stronger hydrogen bonds with polyvinylidene fluoride chains than DMF,which can have a plasticizing effect on the polymer matrix,leading to lower crystallinity and quicker segment ***,this CSE exhibited improved Li-ion conducting properties,enabling the stable cycling of Li‖LiFePO_(4) solid-state *** study provided insights into the role of residual solvents in CSEs.

关键词： Composite solid electrolyte Residual solvent Lithium borohydride Plasticizing effect

Subgrain-assisted spontaneous grain refinement in rapid solidification of undercooled melts

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Journal of Materials Science & Technology 2024年第7期174卷 234-248页

作者： Jianbao Zhang Dongpeng Hua Dexu Cui xin Li ke Hua Yixuan He Haifeng Wang Yuhong Zhao State key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

The grain refinement mechanism for rapid solidification of undercooled melts is still an open problem even after 60 years of on-going *** this work,rapid solidification of undercooled Ni and equi-atomic FeCoNiPd melts was studied and spontaneous grain refinement was found at both low and high *** a detailed electron backscattered diffraction analysis,subgrain-induced grain orien-tation scattering and splitting were found to occur along with the transition from coarse dendrites to fine equiaxed grains at low and high undercooling,respectively,indicating that subgrains play an im-portant role during the formation of fine equiaxed *** this basis,a compromise mechanism of subgrain-assisted spontaneous grain refinement was *** the dendrite re-melting induced thermo-mechanical process and fluid flow induced dendrite deformation occur simultaneously during the post-recalescence stage,stress accumulation would be maximum at both low and high undercooling,thus inducing dynamic recrystallization,during which the formation and rotation of subgrains make the grain orientations scattering and even ***,the grain/subgrain size of undercooled FeCoNiPd ascribing to its unique co-segregation behavior keeps almost invariable from low to high undercooling,indicating that the co-segregation strategy would be effective to inhibit grain growth after rapid solidifi-cation and would be useful in practice.

关键词： Rapid solidification Undercooling Spontaneous grain refinement Grain growth High entropy alloy

MoS_(2) nanoflowers and PEDOT:PSS nanocomposite enabling wearable dual-mode pressure sensors

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Science China(Technological Sciences) 2024年第6期67卷 1737-1747页

作者： WANG FengMing YANG WeiJia MA ke SHEN GengZhe SU DaoJian LI BaiJun WANG ShuangPeng QIN BoLong ZHANG Chi xin Yue CAO XiaoBing HE xin School of Applied Physics and Materials Wuyi UniversityJiangmen529020China Biomaterials R&D Center Zhuhai Institute of Advanced TechnologyChinese Academy of SciencesZhuhai519003China Joint key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoMacao999078China

A versatile sensing platform employing inorganic MoS_(2) nanoflowers and organic poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)has been investigated to develop the resistive and capacitive force-sensitive *** microstructure of the sensing layer heightens the sensitivity and response time of the dual-mode pressure sensors by augmenting electron pathways and inner stress in response to mechanical ***,the capacitive and resistive sensors exhibit sensitivities of 0.37 and 0.12 kPa^(-1),respectively,while demonstrating a remarkable response time of approximately 100 ***,it is noteworthy that the PEDOT:PSS layer exhibits excellent adhesion to polydimethylsiloxane(PDMS)substrates,which contributes to the development of highly robust force-sensitive sensors capable of enduring more than 10000loading/unloading *** combination of MoS_(2)/PEDOT:PSS layers in these dual-mode sensors has shown promising results in detecting human joint movements and subtle physiological ***,the sensors have achieved a remarkable precision rate of 98%in identifying target *** outcomes underscore the significant potential of these sensors for integration into applications such as electronic skin and human-machine interaction.

关键词： MoS_(2)/PEDOT:PSS nanocomposite force-sensitive sensor multi-scaled microstructure physiological signals monitoring object grasping recognition

Exosomal let-7a-5p derived from human umbilical cord mesenchymal stem cells alleviates coxsackievirus B3-induced cardiomyocyte ferroptosis via the SMAD2/ZFP36 signal axis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第5期25卷 422-437页

作者： xin LI Yanan HU Yueting WU Zuocheng YANG Yang liu Hanmin liu Department of Pediatric Pulmonology and Immunology West China Second University HospitalSichuan UniversityChengdu 610041China key Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University) Ministry of EducationChengdu 610041China NHC key Laboratory of Chronobiology(Sichuan University) Chengdu 610041China The Joint Laboratory for Lung Development and Related Diseases of West China Second University Hospital Sichuan University and School of Life Sciences of Fudan UniversityWest China Institute of Women and Children's HealthWest China Second University HospitalSichuan UniversityChengdu 610041China Sichuan Birth Defects Clinical Research Center West China Second University HospitalSichuan UniversityChengdu 610041China Department of Pediatrics the Third Xiangya HospitalCentral South UniversityChangsha 410013China

Viral myocarditis(VMC)is one of the most common acquired heart diseases in children and ***,its pathogenesis is still unclear,and effective treatments are *** study aimed to investigate the regulatory pathway by which exosomes alleviate ferroptosis in cardiomyocytes(CMCs)induced by coxsackievirus B3(CVB3).CVB3 was utilized for inducing the VMC mouse model and cellular *** echocardiography,left ventricular ejection fraction(LVEF),and left ventricular fractional shortening(LVFS)were implemented to assess the cardiac *** CVB3-induced VMC mice,cardiac insufficiency was observed,as well as the altered levels of ferroptosis-related indicators(glutathione) peroxidase 4(GPX4),glutathione(GSH),and malondialdehyde(MDA).However,exosomes derived from human umbilical cord mesenchymal stem cells(hucMSCs-exo)could restore the changes caused by CVB3 ***-7a-5p was enriched in hucMSCs-exo,and the inhibitory ffect of hucMSCs-exoa-ie-pmimo on CVB3-induced ferroptosis was higher than that of hucMSCs-exommie N(NC:negative control).Mothers against decapentaplegic homolog 2(SMAD2)increased in the VMC group,while the expression of zinc-finger protein 36(ZFP36)***-7a-5p was confirmed to interact with SMAD2 messenger RNA(mRNA),and the SMAD2 protein interacted directly with the ZFP36 *** SMAD2 and overexpressing ZFP36 inhibited the expression of ferroptosis-related ***,the levels of GPX4,solute carrier family 7,member 11(SLC7A11),and GSH were lower in the SMAD2 overexpression plasmid(oe-SMAD2)+let-7a-5p mimic group than in the oe-NC+let-7a-5p mimic group,while those of MDA,reactive oxygen species(ROS),and Fe^(2+)*** conclusion,these data showed that ferroptosis could be regulated by mediating SMAD2 ***-let-7a-5p derived from hucMSCs could mediate SMAD2 to promote the expression of ZFP36,which further inhibited the ferroptosis of CMCs to alleviate CVB3-induced VMC.

关键词： Exosome Let-7a-5p Mothers against decapentaplegic homolog 2(SMAD2) Coxsackievirus B3(CVB3) Ferroptosis

Development of an enhanced online tritium monitoring system using plastic scintillation fiber array

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Nuclear Science and Techniques 2024年第10期35卷 239-249页

作者： Wen-Yu Cheng ke Deng You-Shi Zeng Wei liu Qin Zhang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

Tritium,a radioactive nuclide discharged by nuclear power plants,poses challenges for *** online monitoring of tritium in water is crucial for real-time radiation data,given its predominant existence in the environment as *** paper presents the design,simulation,and development of a tritium monitoring device utilizing a plastic scintillation fiber(PSF)*** validation confirmed the device’s detection efficiency and minimum detectable *** recorded detection efficiency of the device is 1.6×10^(-3),which exceeds the theoretically simulated value of 4×10^(-4)by four *** shielding,the device can achieve a minimum detectable activity of 3165 Bq L^(-1)over a 1600-second measurement *** to simulation and experimental results,enhancing detection efficiency is possible by increasing the number and length of PSFs and implementing rigorous shielding ***,reducing the diameter of PSFs can also improve detection *** minimum detectable activity of the device can be further reduced using the aforementioned methods.

关键词： Tritium Plastic scintillating fiber array Detector

Composition design and performance evaluation of rubber-particle cement-stabilized gravel

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Frontiers of Structural and Civil Engineering 2024年第9期18卷 1466-1477页

作者： Chaohui WANG ke YI Feng CHEN Luqing liu Xiaolei ZHOU Zhiwei GAO School of Highway Chang’an UniversityXi’an 710064China Shaanxi Transportation Technology Consulting Co. Ltd.Xi’an 710068China School of Information Engineering Xizang Minzu UniversityXianyang 71208China

To improve the mechanical properties and durability of the cement-stabilized base,rubber particles of three different sizes and with three different contents were optimally selected,the evolution laws of the mechanical strength and toughness of rubber-particle cement-stabilized gravel(RCSG)under different schemes were determined,and the optimal particle size and content of rubber particles were *** this basis,the durability of the RCSG base was *** results show that with an increase in the rubber particle size and content,the mechanical strength of RCSG gradually decreased,whereas the toughness and transverse deformation ability gradually increased.1%content and 2–4 mm sized RCSG can better balance the relationship between mechanical strength and *** 7 d unconfined compressive strength was 17.7%higher than that of the 4–8 mm *** 28 d toughness index and ultimate splitting strain can be increased by 9.8%and 6.3 times,respectively,compared with ordinary cement-stabilized gravel(CSG).In terms of durability,compared with CSG,RCSG showed a 3.7%increase in the water stability property of cement-stabilized base with 1%content and 2–4 mm rubber particles,5.5%increase in the frozen coefficient,and 80.6%and 37.9%increase in the fatigue life at 0.70 and 0.85 stress ratio levels,respectively.

关键词： pavement materials cement-stabilized gravel rubber particles material components mechanical property durability performance