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Journal of Hydrodynamics 2024年第5期36卷 870-882页

作者： Fei-peng Yu Yi-gan Zhang hao-kun li Ze-hui Qu Hua-ping liu School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan430074China

In this paper,a passive control method based on a porous material is applied to the surface of a hemispherical cylinder to control a cavitating flow,and the control effect of this method at different cavitation numbers(σ)is evaluated through the cavity morphology and volume,which is important for the application in *** results indicate that the control effect is improved with a reduction in the cavitation number,for the reduction of vapor volume increases from 22%–50%withσdecreasing from 0.50–*** investigation indicates that the cavity inception at different cavitation numbers is still induced by the Kelvin-Helmholtz instability,while the spatial distribution of the vapor changes ***,the porous material suppresses the cavitating flow in the front region but enhances it downstream at large cavitation ***σ=0.20,the cavitating flow is controlled in both the front and rear regions.

关键词： Cavitation control porous material Kelvin-Helmholtz instability spatial distribution

Utilizing bivalent aptamers as first DNA agonist to activate RTKs heterodimer of different families

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Chinese Chemical Letters 2025年第1期36卷 474-477页

作者： kun liu Yulin Cong Xiongfeng Luo Meicun Yao Zhiyong Xie hao li School of Pharmaceutical Sciences(Shenzhen) Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China

Heterodimerization in RTKs is of vital importance in the RTK signaling and cell *** between RTKs can result in diversity of downstream signals,increasing the ability of cells to respond to external *** RTKs heterodimerization always occur in the same families and is lack of agonists to activate the heterodimeric RTKs signaling ***,we developed the DNA agonist based on bivalent aptamers for the heterodimerized RTKs of different families,AF/AM-1,which could simultaneously activate FGFR1 and c-Met *** is the first agonist that realizing the heterodimerization and activation of FGFR1 and c-Met,two different RTK *** activation of FGFR1/c-Met heterodimer result in the down-stream signals transduction,such as the phosphorylation of Akt and Erk,inducing the cell migration and *** DNA agonist for RTK heterodimer of different families would have potential applications in the fields of biomedicine.

关键词： DNA Agonist Bivalent aptamers RTKs heterodimer

Influence of heat treatment on microstructure of a newβ-solidifyingγ-TiAl alloy

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Journal of Iron and Steel Research International 2025年第1期32卷 239-248页

作者： li Quan Xiao-bing li Peng Xue Jun-jie hao kun Qian Bo Chen Jian-zhong li Kui liu School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Department of Materials Science and Technology Ji Hua LaboratoryFoshan528200GuangdongChina

The high strength and stability of the full-lamellar structure guarantee the industrial application of theβ-solidifyingγ-TiAl ***,it is a huge challenge to design an alloy with good hot-deformability as well as the full-lamellar *** low-cost Ti-42.5Al-2Mn-0.4Mo-0.1B-0.1C(at.%)alloy was designed,which undergoes bothβandαsingle-phase region during the *** is found that the full-lamellar structure can be obtained by the solution heat treatment at 1230℃ for 20 min and then aging treatment at 800℃ for 3 ***,a new microstructure,namely,the pearlitic-like microstructure(PM)induced by theα_(2)/γ→βo+γcellular reaction was observed when the aging temperature is increased to above 800℃.The volume fraction of the PM is gradually increased from 0%to 25.5%,65%,and 94%according to elevated aging temperature from 800 to 900,1000,and 1050℃,*** mechanism of the reducedα_(2)/γlamellae and PM formation was discussed regarding the heterogeneous distribution ofβstabilizing elements and the interface energy stored inα_(2)/γlamellae.

关键词： β-γ-TiAl Alloy design Two-step heat treatment Full-lamellar structure Cellular reaction

Omnidirectional simulation analysis of thermomechanical coupling mechanism in inertia friction welding of Ni-based superalloy

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Chinese Journal of Aeronautics 2025年第1期38卷 202-216页

作者： Chang-an li Guoliang QIN hao WANG School of Materials Science and Engineering Shandong UniversityJinan 250061China

The coupling between heat and pressure is the kernel of inertia friction welding(IFW)and is still not fully understood.A novel 3D fully coupled finite element model based on a plastic friction pair was developed to simulate the IFW process of a Ni-based superalloy and reveal the omnidirectional thermo-mechanical coupling mechanism of the friction *** numerical model successfully simulated the deceleration,deformation processes,and peak torsional moments in IFW and captured the evolution of temperature,contact pressure,and *** simulated results were validated through measured thermal history,optical macrography,and axial *** results indicated that interfacial friction heat was the primary heat source,and plastic deformation energy only accounted for 4%of the *** increase in initial rotational speed and friction pressure elevated the peak temperature,reaching a maximum of 1525.5K at an initial rotational speed of 2000 r/min and friction pressure of 400 *** interface heat generation could form an axial temperature gradient exceeding 320K/*** radial inhomogeneities of heat generation and temperature were manifested in a concentric ring distribution with maximum heat flux and temperature ranging from 2/5 to 2/3 *** radial inhomogeneities were caused by increasing linear velocity along the radius and an opposite distribution of contact pressure,which could reach 1.7 times the set pressure at the *** circumferential inhomogeneity of thermomechanical distribution during rotary friction welding was revealed for the first time,benefiting from the 3D *** deflection and transformation of distribution in contact pressure and Mises stress were indicators of plastic deformation and transition of quasi-steady state *** critical Mises stress was 0.5 times the friction pressure in this *** presented modeling provides a reliable insight into the thermo-mechanical coupling mechanism of IFW and lays a solid found

关键词： Inertia friction welding Thermo-mechanical coupling Inhomogeneity Numerical simulation Ni-based superalloy

Ti^(3+)/Ti^(4+)and Co^(2+)/Co^(3+)redox couples in Ce-doped Co-Ce/TiO2 for enhancing photothermocatalytic toluene oxidation

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Journal of Environmental Sciences 2025年第3期149卷 164-176页

作者： Guanghui li Xiaolan li Xinhui hao Qiang li Meng Zhang Hongpeng Jia Xiamen Key Laboratory of Materials for Gaseous Pollutant Control Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China CAS Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Cerium and cobalt loaded Co-Ce/TiO_(2)catalyst prepared by impregnation method was investigated for photothermal catalytic toluene *** on catalyst characterizations(XPS,EPR and H2-TPR),redox cycle between Co and TiO_(2)(Co^(2+)+Ti^(4+)↔Co^(3+)+Ti^(3+))results in the formation of Co^(3+),Ti^(3+)and oxygen vacancies,which play important roles in toluene catalytic oxidation *** introduction of Ce brings in the dual redox cycles(Co^(2+)+Ti^(4+)↔Co^(3+)+Ti^(3+),Co^(2+)+Ce4+↔Co^(3+)+Ce3+),further promoting the elevation of reaction sites *** full spectrum irradiation with light intensity of 580mW/cm^(2),Co-Ce/TiO_(2)catalyst achieved 96%of toluene conversion and 73%of CO_(2)yield,obviously higher than Co/P25 and Co/TiO_(2).Co-Ce/TiO_(2)efficiently maintains 10-hour stability test under water vapor conditions and exhibits better photothermal catalytic performance than counterparts under different wavelengths *** catalytic reaction displays improved activities compared with thermal catalysis,which is attributed to the promotional effect of light including photocatalysis and light activation of reactive oxygen species.

关键词： Photothermal catalysis Redox cycle Oxygen vacancy VOCs Titanium dioxide

Significant improvement of machinability of C_(f)/SiC composites through matching laser scanning spacing and abrasive belt grain size

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Chinese Journal of Aeronautics 2025年第1期38卷 185-201页

作者： Guijian XIAO Zhengyu YANG kun ZHOU Yi HE Xin li College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China State Key Laboratory of Mechanical Transmissions for Advanced Equipment Chongqing UniversityChongqing 400044China

To improve the application and service of C_(f)/SiC composites as advanced hightemperature structural materials,it is critical to achieve their high-efficiency and low-damage *** this study,the laser-ablating assisted grinding(LAAG)method was presented,and the connection of damage behavior and removal mechanism with laser and grinding processes was *** results demonstrated that the surface of C_(f)/SiC composites after laser ablation was covered with a substantial number of loose oxides primarily composed of *** ablating process,grinding parameter and abrasive belt selection have a significant impact on the machining *** fabricating an ablative layer with small laser scanning spacing,and selecting small abrasive grains and feed rate during grinding,the machinability was improved and a relatively lowerdamage grinding surface could be *** the optimal combination of process parameters,the grinding force and temperature of LAAG could be reduced by up to 85%and 35%,*** this case,the subsurface damage of C_(f)/SiC composites occurred only in the form of microcracks rather large-scale fracture,and the formation of interface debonding and matrix cracking was significantly ***,the grinding chips were mostly shown as micron-sized powders,indicating that the removal mechanism of C_(f)/SiC composites was primarily the microfractured and attrition wear of laser-ablated layer.

关键词： Ceramic matrix composites Laser ablating Grinding Material removal Fracture damage

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Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： Ruo-Hang Xu hao-Yu Jiang Dan-Dan Cui kun-Rong Du Hong-Run Zhang Sheng-Jie Xu Ya-Qi li Zhi-Zhen Ren liang Wang Wei-Chang hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts

Targets capture by distributed active swarms via bio-inspired reinforcement learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 206-217页

作者： kun Xu Yue li Jun Sun Shuyuan Du Xinpeng Di Yuguang Yang Bo li Institute of Biomechanics and Medical Engineering Applied Mechanics LaboratoryDepartment of Engineering MechanicsTsinghua UniversityBeijing 100084China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Shanghai Aerospace Control Technology Institute Shanghai 201109China Shanghai Key Laboratory of Aerospace Intelligent Control Technology Shanghai 201109China College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common *** from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific ***,we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement *** exploit collective milling structures of natural herds to cage the targets,and adopt a switching control policy inspired by sperms’chiral dynamics to optimize the trajectories of individuals,through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical,adaptive and scalable *** exists a critical swarm size,beyond which the excessive competition between agents would generate large mechanical forces,leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple *** work provides physical insights into distributed active swarms and could offer a multilevel,decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices,machine immunity,and target clearance.

关键词： swarm intelligence robotics multi-tasks artificial intelligence bionics

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A new exceptionally preserved corystosperm wood from the Jurassic of East Asia

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Science China Earth Sciences 2025年第3期68卷 803-810页

作者： Zikun JIANG Ning TIAN Yongdong WANG Fangyu li Junling PEI Dieter UHL Ya li hao WU Zhenguo NING Ruiying hao Chinese Academy of Geological Sciences College of Palaeontology Shenyang Normal University Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences College of Resources and Environmental Engineering Guizhou University East China University of Technology Senckenberg Research Institute and Natural History Museum Frankfurt Zhejiang Museum of Natural History Department of Natural Resources of Shandong Province

Corystosperms, an extinct group of “seed ferns” that lived from the late Permian to the Cretaceous or Eocene, are significant for seed plant phylogeny for their unique roles in partially resolving the long-standing question of angiosperm origins.A new fossil wood taxon, Fengweioxylon sinense gen. et sp. nov. is reported here based on exceptionally preserved wood material from the Jurassic in western liaoning, China, whose peculiar wood structure enables it to be recognized as the first unequivocal fossil wood record of a corystosperm plant in Laurasia. The anatomical structures of this corystosperm wood show gymnospermous characters. The discovery of the new specimen will provide more anatomical evidence for understanding the systematic and affinity of this seed plants.

关键词： Corystosperms Fossil wood Laurasia Jurassic

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Highly Oxidized Molecules Make a Significant Contribution to Enhanced Aromatic-Derived Secondary Organic Aerosol under a Humid Environment

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Advances in Atmospheric Sciences 2025年第4期42卷 641-652页

作者： Zhaomin YANG kun li lin DU Environment Research Institute Shandong UniversityQingdao 266237China

Enhanced mass concentrations of aromatic-derived secondary organic aerosol(SOA)are frequently observed during humid-haze ***,the influencing mechanism of relative humidity(RH)in aromatic-derived SOA formation remains incompletely ***,the RH dependence of SOA formation in the presence of NOx was explored by a series of chamber experiments for toluene(TOL)and 1,3,5-trimethylbenzene(TMB)*** yield of TOL SOA and TMB SOA increased by 221%and 52%with increasing RH from~8%to~70%,*** results from a high-resolution mass spectrometer showed that SOA constituents with high oxygen content(O/C>0.6)were more abundant in SOA formed in the~70%RH *** elevated yields and O/C of SOA could be attributed to the promoted formation and particle-phase diffusivity of highly oxidized *** addition,in comparison with TMB,TOL could produce more unsaturated aldehydes,which are oxidized into carboxylic acids with high O/C,leading to a more sensitive response of TOL SOA formation to the change in *** work provides mechanistic insights into RH roles in aromatic SOA formation and is helpful for a better understanding of humid-haze events.

关键词： secondary organic aerosol aromatic hydrocarbons highly oxidized molecules relative humidity