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On Affine Hypersurfaces with Parallel Cubic Form Relative to Affineα-connection

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1099-1114页

作者： Ce Ce li Cheng xing Hui yang XU School of Mathematics and Statistics He’nan University of Science and TechnologyLuoyang 471023P.R.China School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071P.R.China

Similar to Nomizu-Pinkall's geometric characterization of the Cayley surface and Hu-li-Zhang's characterization of the Cayley hypersurface,how can one characterize the generalized Cayley hypersurfaces?In this paper,by the affineα-connection of statistical manifolds,we study affine hypersurfaces with parallel cubic form relative to the affineα-*** the main results,we complete the classification of such hypersurfaces if its affine metric is either definite,or Lorentzian withα≠-***,we give a new characterization of the generalized Cayley hypersurfaces to answer the question.

关键词： Affine hypersurface parallel cubic form affineα-connection Einstein metric

Improving flangeability of multiphase steel by increasing microstructural homogeneity

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Journal of Iron and Steel Research(International) 2024年第7期31卷 1736-1745页

作者： Xiao-yu yang Yong-gang yang xing Fang Han-long Zhang Zhen-li Mi Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Engineering TechnologyUniversity of Science and Technology BeijingBeijing 100083China Shanghai Baosteel Group Corp.Technology Center Shanghai 201900China

Multiphase microstructure significantly increases the strength,usually at the expense of flangeability because of lacking microstructure *** further improve the strength-flangeability of multiphase steel,the microstructural homogeneity was advanced by adjusting the hard martensite/austenite(M/A)*** strength-flangeability was measured via uniaxial tensile tests and hole expansion *** microstructures were characterized using a scanning electron microscope equipped with an electron backscatter diffraction detector and a transmission electron *** tests were supplementally used to quantitatively reveal the microstructural homogeneity of the *** show that the adjusted multiphase steel achieves an excellent ultimate tensile strength(~800 MPa)and flangeability(~135%hole expansion ratio).A promising homogeneous multiphase microstructure was obtained by controlling undercooled austenite transformed at about 600℃.This microstructure consists of soft polygonal ferrite,blocky bainitic ferrite,and hard M/A *** volume fraction of M/A islands is around 5%,and the average size is less than l *** nanoindentation analysis indicated that the participation of M/A islands impressively influenced the microstructural *** strain partition and better mechanical compatibility were present in the adjusted multiphase steel since the plasticity initiation started late,which resulted in a positive ***,avoiding M/A islands distributed in the chain along the rolling direction on the matrix hindered the possibility of voids coalescing into cracks and stabilized the flanging performance.

关键词： Multiphase steel Flangeability Martensite/austenite island-Microstructural homogeneity-Microstructure Compact strip production process

LPCS Ni-Zn-Al_(2)O_(3) Intermediate Layer Enhanced SPS NiCr-Cr_(3)C_(2) Coating with Higher Corrosion and Wear Resistances

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 188-195页

作者：白杨 li Yan xing Lukuo li Xiangbo WANG Zhenhua State Key Laboratory of Marine Coatings Marine Chemical Research Institute Co.Ltd.Qingdao 266071China College of Mechanical and Electrical Engineering University of China Petroleum(East China)Qingdao 266580China Science and Technology on Marine Corrosion and Protection Laboratory Luoyang Ship Materials Research InstituteQingdao 266101China

The double-layer NiCr-Cr_(3)C_(2)/Ni-Zn-Al_(2)O_(3) coatings with sufficient corrosion and wear resistance were prepared on low carbon steel *** intermediate layers Ni-Zn-Al_(2)O_(3) were fabricated by using low-pressure cold spray (LPCS) method to improve the salt fog corrosion resistance properties of the supersonic plasma spray (SPS) NiCr-Cr_(3)C_(2) *** friction and wear performance for the double-layer and single-layer NiCr-Cr_(3)C_(2) coatings were carried out by line-contact reciprocating sliding,*** with the coating surface analysis techniques,the effect of the salt fog corrosion on the tribological properties of the double-layer coatings was *** results showed that the double-layer coatings exhibited better wear resistance than that of the single-layer coatings,due to the better corrosion resistance of the intermediate layer;the wear mass losses of the double-layer coatings was reduced by 70%than that of the single layer coatings and the wear mechanism of coatings after salt fog corrosion conditions is mainly corrosion wear.

关键词： low-pressure cold spray NiCr-Cr_(3)C_(2)coating wear behavior salt fog corrosion

What is the Role of Gravity,Turbulence and Magnetic Fields in High-mass Star Formation Clouds?

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Research in Astronomy and Astrophysics 2024年第6期24卷 21-27页

作者： An-Xu Luo Hong-li liu Guang-xing li Sirong Pan Dong-Ting yang School of Physics and Astronomy Yunnan UniversityKunming 650091China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China

To explore the potential role of gravity,turbulence and magnetic fields in high-mass star formation in molecular clouds,this study revisits the velocity dispersion–size(σ–L)and density–size(ρ–L)scalings and the associated turbulent energy spectrum using an extensive data *** sample includes various hierarchical density structures in high-mass star formation clouds,across scales of 0.01–100 *** observeσ∝L^(0.26)andρ∝L^(-1.54)scalings,converging toward a virial equilibrium state.A nearly flat virial parameter–mass(α_(vir)-M)distribution is seen across all density scales,withα_(vir)values centered around unity,suggesting a global equilibrium maintained by the interplay between gravity and turbulence across multiple *** turbulent energy spectrum(E(k))analysis,based on theσ–L andρ–L scalings,yields a characteristic E(k)∝k^(-1.52).These findings indicate the potential significance of gravity,turbulence,and possibly magnetic fields in regulating dynamics of molecular clouds and high-mass star formation therein.

关键词： ISM:clouds stars:formation stars:kinematics and dynamics

Biomimetic porous silicon oxycarbide ceramics with improved specific strength and efficient thermal insulation

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Journal of Materials Science & Technology 2024年第1期168卷 185-193页

作者： Zhuoqing Zhang Jinghan li Lei Cao Yu Shi Huajie yang Rui yang Fan Xie xing Zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China Shenyang Aircraft Design and Research Institute Shenyang 110035China

Considering the challenge of aerodynamic heating,the development of high-performance insulating ce-ramic materials with lightweight and low thermal conductivity is crucially important for aerospace vehi-cles to achieve flight at high speed for a long *** this work,macro-porous silicon oxycarbide(SiOC)ceramics with directional pores(DP-SiOC)(mean pore size of 88.1μm)were prepared using polysiloxane precursors via freeze casting and photocrosslinking,followed by *** DP-SiOC samples were lightweight(density∼0.135 g cm^(-3))with a porosity of 90.4%,which showed good shapability through the molding of polysiloxane *** DP-SiOC samples also exhibited an ultra-low thermal con-ductivity of 0.048 W(m K)^(-1)at room temperature,which can also withstand heat treatment at 1200°C for 1 *** addition,scaffolds with triply periodic minimal surfaces(TPMS)were fabricated using digital light processing(DLP)printing,which was further filled with polysiloxane precursors for increasing the strength of *** TPMS scaffolds filled with macro-porous SiOC ceramics(TPMS-DP-SiOC)showed good integration between TPMS and macro-pore structures,which had a porosity∼75%and high specific strength of 9.73×10^(3)N m kg^(-1).The thermal conductivity of TPMS-DP-SiOC samples was 0.255 W(m K)^(-1)at room *** biomimetic TPMS-DP-SiOC ceramics developed in this study are likely used for thermal protection systems.

关键词： Thermal insulation light weight Macro-porous ceramics SiOC

Thiol-mediated transportation pathway:an approach for improving tumor penetration of nanomedicines in vivo

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Science China Chemistry 2024年第1期67卷 383-389页

作者： Junjie Zhang Weican Sun xing Wang Senyan Chen Jingying li Huanghao yang New Cornerstone Science Laboratory Key Laboratory for Analytical Science of Food Safety and Biology(Ministry of Education)College of ChemistryFuzhou UniversityFuzhou 350116China Department of Chemistry and College of Biological Science and Engineering Fuzhou UniversityFuzhou 350116China

Abnormal tumor microenvironment imposes barriers to tumor penetration of nanomedicine,which remains a major challenge for effective ***,we present disulfide-based nanoparticles that actively penetrate deep tumors in vivo through a thiol-mediated transportation *** achieve active tumor accumulation in vivo,disulfide-based nanoparticles are modified with folic acid units(FA-DBNPs).It is gratifying that FA-DBNPs still enter cells via the thiol-mediated pathway,which facilitates transcellular transportation and tumor penetration both in vitro and in ***,FA-DBNPs exhibit GSH concentration-dependent depolymerization characterization,indicating that the GSH level in tumor tissues regulates the penetration depth of *** from these advantages,FA-DBNPs showed potent anti-tumor activity in mouse models,leading to the significant regression of *** current study lays a foundation that thiol-mediated transportation is a promising approach in nanomedicine design for solid tumor therapy.

关键词： deep penetration thiol-mediated pathway transcellular transportation solid tumor

Unimolecular Self-Assembled Hemicyanine-Oleic Acid Conjugate Acts as a Novel Succinate Dehydrogenase Inhibitor to Amplify Photodynamic Therapy and Eliminate Cancer Stem Cells

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Research 2024年第2期6卷 449-461页

作者： Qiang Wang Tian yang Shiyou li Chen Xu Chong Wang Yuxuan Xiong xing Wang Jiangling Wan Xiangliang yang Zifu li National Engineering Research Center for Nanomedicine College of Life Science and Technology.Huazhong University of Science and TechnologyWuhan 430074P.R.China Key Laboratory of Molecular Biophysics of Ministry of Education College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074P.R.China .3Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medical Huazhong University of Science and TechnologyWuhan 430074P.R.China Hubei Engineering Research Center for Biomaterials and Medical Protective Materials Huazhong University of Science and TechnologyWuhan 430074P.R.China Hubei Bioinformatics and Molecular Imaging Key Laboratory College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074P.R.China

Photodynamic therapy with reactive oxygen species production is a prospective treatment to combat cancer stem cells(CSCs).However,the innate drawbacks,including short lifetime and diffusion distance of reactive oxygen species and hypoxia within solid tumors,have become bottlenecks for clinical applications of photodynamic ***,we develop a mitochondria-targeting hemicyanine-oleic acid conjugate(CyOA),which can self-assemble into supramolecular nanoparticles(NPs)without any exogenous *** is also shown for targeting the mitochondrial complex II protein succinate dehydrogenase to inhibit oxidative phosphorylation and reverse tumor hypoxia,resulting in 50.4-fold higher phototoxicity against breast cancer stem cells(BCSCs)compared to SO_(3)-CyOA NPs that cannot target to *** 4T1 and BCSC tumor models,CyOA NPs achieve higher tumor inhibition and less lung metastasis nodules compared to the clinically used photosensitizer *** study develops a self-assembled small molecule that can serve as both oxidative phosphorylation inhibitor and photosensitizer for eradication of CSCs and treatment of solid tumors.

关键词： cyanine oxidative treatment

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X波段单面场微带隔离器设计

磁性材料及器件 2024年第4期55卷 62-66页

作者：孙静陈宁高男杜俊波王倩李扬兴中国电子科技集团公司第九研究所四川绵阳621000

针对提升微带器件隔离度的需求,根据微带环行器的设计理论,设计了一种工作在X波段的高隔离度、高温度稳定性的单面场微带隔离器。通过对微带器件工作模式分析,提出开缝六边形结匹配矩形开路负载的电路结构。测试结果表明,采用开缝六边... 详细信息

针对提升微带器件隔离度的需求,根据微带环行器的设计理论,设计了一种工作在X波段的高隔离度、高温度稳定性的单面场微带隔离器。通过对微带器件工作模式分析,提出开缝六边形结匹配矩形开路负载的电路结构。测试结果表明,采用开缝六边形结匹配矩形开路负载电路结构设计的X波段单面场微带隔离器,在11~11.4 GHz工作频率内、-55~+85℃温度下,插入损耗小于0.3 dB,电压驻波比小于1.3,隔离度大于23 dB,达到设计要求。

关键词：单面场微带隔离器 X波段隔离度开缝六边形结电路结构

Inhibiting shuttle effect of lithium polysulfides by double metal selenides for high-performance lithium-sulfur batteries

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Rare Metals 2024年第6期43卷 2546-2559页

作者： Lei li Xue-Jing yang Yi-yang li Bo Jin Hui liu Meng-yang Cui Dong-Bo Guan xing-You Lang Qing Jiang Key Laboratory of Automobile Materials Ministry of Educationand College of Materials Science and EngineeringJilin UniversityChangchun 130022China

lithium-sulfur batteries(LSBs)have attracted the attention of more and more researchers due to the advantages of high energy density,environmental friendliness,and low production ***,the low electronic conductivity of active material and shuttling effect of lithium polysulfides(liPSs)limit the commercial development of *** solve these problems,we design a core-shell composite with nitrogen-doped carbon(NC)and two types of selenides(FeSe_(2)-NC@ZnSe-NC).The FeSe_(2)-NC@ZnSe-NC has a strong adsorption capacity,and can effectively adsorb *** the same time,it also effectively alleviates the shuttling effect of liPSs,and improves the utilization of the active substance during the charge/discharge reaction *** mechanism involved in FeSe_(2)-NC@ZnSe-NC is demonstrated by both experiments and density-functional theory(DFT)*** electrochemical test results indicate that LSB with S/FeSe_(2)-NC@ZnSe-NC delivers an initial discharge capacity of 1260 mAh·g^(-1)at *** after 500 cycles at 1C,the capacity decay rate per cycle is 0.031%,and the capacity retention rate is 85%.The FeSe_(2)-NC@ZnSe-NC core-shell structure verifies a rational strategy to construct an electrode material for high-performance LSBs.

关键词： lithium-sulfur batteries Shuttling effect Metal selenide Nitrogen-doped carbon lithium polysulfides