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Acta Mathematica Sinica,English Series 2024年第6期40卷 1521-1532页

作者： Peng Cheng li dong He PEI Xin ZHAO School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China Department of Mathematics Harbin Institute of TechnologyWeihai 264209P.R.China School of Mathematics and Statistics Qingdao UniversityQingdao 266071P.R.China

In this paper,we define the evolute and focal surface of a spacelike framed curve with lightlike components in Minkowski *** is a generalization of the previous results of regular spacelike curves,since singularities are allowed in the original spacelike curves studied by spacelike framed curves with lightlike ***,we show a new geometric invariant to characterise singularities of the focal ***,the classification theorem and recognition theorem for the singularities of the focal surface in generic are also given.

关键词： Evolutes focal surfaces spacelike framed curves singularities

Fully fluorinated hybrid zeolite imidazole/Prussian blue analogs with combined advantages for efficient oxygen evolution reaction

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Chinese Chemical Letters 2024年第6期35卷 222-228页

作者： Jiayu Xu Meng li Baoxia dong ligang Feng School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Hybrid metal-organic framework(MOF)derivatives play a significant role in the novel catalyst development in energy conversion ***,we demonstrated the low-temperature fully fluorinated zeolitic imidazole framework(ZIF)coupled with a three-dimensional open framework Prussian blue analog(PBA)with combined advantages for electrocatalytic oxygen evolution reaction(OER)in water splitting *** spectroscopic analysis and the electrochemical studies revealed the combined advantages of efficient electronic effect and active site *** of good conductivity improvement by Ndoped carbon derived from ZIF and the high electrochemical surface area and active site exposure from PBA derivatives,good catalytic performance was obtained on the optimal catalyst of Co Ni ZIF/Co Fe-PBAF-300,which required a low overpotential of 250 m V to reach 10 m A/cm^(2)loaded on the glassy carbon electrode,with Tafel slope of 47.4 m V/dec,and very high dynamic and steady *** addition,the multi-component with the mixed structure from highly polar metal fluorides promoted the easy formation of the active phase as revealed by the post-sample *** current results showed a novel composite catalyst materials development from the hybrid MOF derivatives,which would be promising in the electrolysis of water oxidation reactions and energy-relevant catalysis reactions.

关键词： Metal-organic framework Zeolitic imidazole framework Prussian blue analog Fluoridation Multi-component Oxygen evolution reaction

Weighted Composition Operators That Preserve Frames On Weighted Hardy Spaces

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1645-1654页

作者： Ya li dong Rui liu Guo Xiang Lu School of Mathematical Sciences and LPMC Nankai UniversityTianjin300071P.R.China School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan430073P.R.China

In this paper, we characterize weighted composition operators that preserve frames on the weighted Hardy spaces in the unit disk. In particular, we obtain the symbol properties of the bounded invertible weighted composition operators. Moreover, we establish the equivalence between bounded invertible operators and frame-preserving operators. Furthermore, we show that weighted composition operator preserves frames if and only if it preserves the Riesz bases property. Additionally,we investigate the weighted composition operators that preserve tight or normalized tight frames on the Dirichlet space.

关键词： Weighted composition operators Weighted Hardy spaces frames invertible

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Noise Effect on the 2D Stochastic Burgers Equation

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2065-2090页

作者： Zhao dong Jiang Lun WU Guo li ZHOU RCSDS Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China Beijing Normal University-Hong Kong Baptist University United International College Zhuhai 519087P.R.China Guangdong Provincial Key Laboratory of Interdisciplinary Research and Application for Data Science(IRADS) UICZhuhai 519087P.R.China School of Statistics and Mathematics Chongqing University Key Laboratory of Nonlinear Analysis and Its Applications(Chongqing University) Ministry of EducationChongqing 400044P.R.China

By comprehensive utilizing of the geometry structure of 2D Burgers equation and the stochastic noise,we find the decay properties of the solution to the stochastic 2D Burgers equation with Dirichlet boundary ***,the e... 详细信息

关键词： 2D stochastic Burgers equation regularity

Ergodicity of 3D Stochastic Burgers Equation

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Acta Mathematica Sinica,English Series 2024年第2期40卷 498-510页

作者： Zhao dong Jiang Lun WU Guo li ZHOU RCSDS Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China Department of Mathematics Computational FoundrySwansea UniversitySwansea SA18ENUK College of Mathematics and Statistics Chongqing UniversityChongqing 400044P.R.China

3D Burgers equation is an important model for *** is natural to expect the long-time behaviour for this hydrodynamics ***,there is no result about the long-time behaviour for this deterministic ***,if the system is perturbed by stochastic noise,we establish the existence and uniqueness of invariant measure for 3D stochastic Burgers equation.

关键词： 3D stochastic Burgers equations maximum principle ergodicity

Green Synthesis of Iron(Ⅱ,Ⅲ)-polyphenol Nanoparticles and Their Adsorption of Malachite Green

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 1025-1030页

作者：胡玉 ZHOU fan ZHANG Nan PAN Xiaobin li Shiying ZHANG dong li li 张玲帆 Department of Chemistry and Environmental Engineering Hanjiang Normal UniversityShiyan 442000China Shiyan Hydrological and Water Resources Survey Bureau of Hubei Province Shiyan 442000China School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai 200237China

Three kinds of iron nanoparticles(FeNPs)were prepared via green route based on pomegranate(PG),green tea(GT),and mulberry(ML)extracts under ambient *** obtained materials were characterized by scanning electron microscopy(SEM),transmission electronic microscopy(TEM),X-ray energy-dispersive spectrometer(EDS),X-ray diffraction(XRD),fourier transform infrared spectroscopy(FTIR),and X-ray photoelectron spectroscopy(XPS)*** experimental results show that FeNPs were in the form of amorphous iron(Ⅱ,Ⅲ)-polyphenol complex with different dispersity and ***-Fe has the smallest size range of 25-35 nm,PG-Fe has a moderate size-distribution of 30-40 nm,while ML-Fe formed a tuberous net-type with a sheeting ***-Fe displays the highest removal efficiency of 90.2%in 20 min towards cationic dye of malachite green(16.6%by ML-Fe and 69.3%by GT-Fe),which is attributed to its highest polyphenol content,lowest zeta potential,as well as the most Fe^(2+)on the surface of *** removal mechanism was mainly induced by electrostatic adsorption based on pH and zeta potential tests.

关键词： iron nanoparticles pomegranate green tea mulberry adsorption

Multiscale microstructural consideration of enhanced shear strength in TiAl intermetallic/K4169 alloy composite joints prepared by vacuum brazing with(Ti,Zr)-Ni-based amorphous filler metal

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Journal of Materials Science & Technology 2024年第5期172卷 51-70页

作者： liangliang Zhang Honggang dong Peng li Baosheng Wu Yueting Ma libing Huang Chao li Jiachen li School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China

TiAl intermetallic could be used to replace Ni-based alloy in assemblies to generate excellent specific strength.A(Ti,Zr)-Ni-based amorphous filler metal Ti_(21.25)Zr_(25)Ni_(25)Cu_(18.75)(at.%)was designed using a cluster-plus-glue-atom model to successfully vacuum braze K4169 and TiAl bimetallic *** various brazing temperatures and holding time,the quantitative relationships between lattice distortion,grain boundary,dislocation density,and hardness,elastic modulus,shear strength of the joints were ***,the fracture mechanism of the joints was *** brazed seam mainly consisted of solid diffusion reaction layers(ZonesⅠandⅢ)and filler metal residue zone(ZoneⅡ).When the brazing temperature increased to 1030℃,grain refinement occurred in the brazed ***Ⅰwas primarily composed of(Ni)ss[0-11]+TiNi[011]/(Cr,Fe,Ni)ss[0-11]/(Ti,Zr)Ni[0-1-1]+(Cr,Fe,Ni)ss[0-11].The(Ti,Zr)(Ni,Cu)[001]and(Ti,Zr)(Ni,Cu)[101]intermetallic compound-based solid solutions were formed in ZoneⅡ.And the lattice distortion of(Ti,Zr)(Ni,Cu)[101]and(Ti,Zr)(Ni,Cu)[001]was 32.05%and 14.82%,*** a result,the proportion of low angle grain boundaries(LAGBs)and deformed grains in ZoneⅡrose to 38.6%and 38.7%.In ZonesⅠandⅢ,the proportion of LAGBs reduced to 8%and 3.4%,*** the holding time increased,the long-range diffusion of Al in ZoneⅡcaused the(Ti,Zr)(Ni,Cu)[001]with cubic structure to transform into(Ti,Zr)(Ni,Cu,Al)[00-1]with hexagonal crystal system structure,where the lattice distortion was 4.42%and 10.49%for a and *** 1030℃/10 min,the average geometrically nec-essary dislocation densities(GNDs)in ZonesⅠ,ⅡandⅢwere 9.87×10^(14)m^(-2),8.55×10^(14)m^(-2)and 11.4×10^(14)m^(-2),***,the shear strength of joints reached 322 MPa due to the lattice distortion,dislocation strengthening and fine grain ***,the plastic and brittle hard phases were generated in ZoneⅡand displayed a mechanical interlocking structure tha

关键词： K4169/Ti_(21.25)Zr_(25)Ni_(25)Cu_(18.75)/TiAl composite joints Intermetallic compound-based solid solution Lattice distortion Elastic modulus

Numerical investigation on the flow and thermal behaviors of the volumetric solar receivers with different morphologies

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Science China(Technological Sciences) 2024年第9期67卷 2749-2757页

作者： DU Shen li dong li MengJie HE Yaling National Innovation Platform(Center)for Industry-Education Integration of Energy Storage Technology Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of EducationXi’an Jiaotong UniversityXi’an 710049China

Morphologies of the porous materials influence the processes of solar radiation transport, flow, and thermal behaviors within volumetric solar receivers. A comprehensive comparative study is conducted by applying pore scale numerical simulations on volumetric solar receivers featuring various morphologies, including Kelvin, Weaire-Phelan, and foam configurations. The idealized unit cell and X-ray computed tomography scan approaches are employed to reconstruct pore scale porous *** Carlo ray tracing and pore scale numerical simulations are implemented to elucidate the radiative, flow, and thermal behaviors of distinct receivers exposed to varying thermal boundary conditions and real irradiation situations. The findings demonstrate that the foam structure exhibits greater solar radiation absorptivity, while Kelvin and Weaire-Phelan structures enhance the penetration depth under non-perpendicular solar irradiation. In comparison with Kelvin and Weaire-Phelan configurations, the foam structure presents efficient convective heat transfer, with the Weaire-Phelan structure showing pronounced thermal non-equilibrium phenomena. The variance in convective heat transfer coefficient between Kelvin and Weaire-Phelan configurations is approximately 8.4%. The foam structure exhibits higher thermal efficiency and flow resistance under nonperpendicular irradiation compared to Kelvin and Weaire-Phelan structures, attributed to its smaller pore size and intricate flow channels. An increase of 1.3% in thermal efficiency is observed with a substantial rise in pressure drop of 32.2%.

关键词： volumetric solar receiver porous morphology pore scale method solar radiation absorption thermal performance flow resistance

Comparison of corrosion mechanisms of 510L low alloy steel treated by ACS and EPS techniques under various service environments

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Journal of Iron and Steel Research International 2024年第2期31卷 501-518页

作者： Bao-sheng liu Peng-fei Xu Shao-hua Zhang Yan-rui li li-ming Mou Jia-li li Yue-zhong Zhang Pei-mao Fu fa-cai Shi College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina College of Chemical and Biological Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina Technical Center Taiyuan Iron and Steel(Group)Co.Ltd.Taiyuan030003ShanxiChina

The corrosion mechanism of 510L low alloy steel treated by acid-cleaned surface(ACS)and eco-pickled surface(EPS)techniques in three simulated solutions(S0:atmospheric environment;S1:soil environment;S2:industrial environment)and the influence of interaction between different corrosive anions on corrosion were *** results show that the total corrosion rates of samples in three simulated solutions were in order of S2>S0>S1,which is simultaneously correlated with initial corrosion dissolution processes as well as after the formation of corrosion ***3−will inhibit the initial corrosion owing to the formation of films,whereas HSO3−will accelerate the dissolutions of the matrix based on the synergistic action of HSO3−and Cl−.On the other hand,there is no significant difference in corrosion rates between the samples treated by ACS and EPS *** EPS technique that is safe,reusable and environmentally friendly can be further widely used in future work.

关键词： Corrosion mechanism Low alloy steel Simulated solution Surface technique Immersion time

Tetrabromobisphenol A exerts thyroid disrupting effects but has little overt impact on postnatal brain development and neurobehaviors in mice

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Journal of Environmental Sciences 2024年第8期142卷 1-10页

作者： Shilin Song Yuanyuan li lin Lv Mengqi dong Zhanfen Qin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China School of Environment Tsinghua UniversityBeijing 100084China

Tetrabromobisphenol A(TBBPA)is a widely used brominated flame *** is evidence showing that TBBPA can exert thyroid disrupting effects in mammals,but different results were also reported,along with inconsistent reports regarding its ***,we investigated thyroid disrupting effects and neurotoxicity of TBBPA(5,50,500μg/(kg·day))to male mice following maternal and direct exposure through drinking water,with the antithyroid drug propylthiouracil(PTU)as the positive *** postnatal day(PND)15,we expectedly observed severe thyroid compensatory hyperplasia and cerebellar developmental retardation in PTU-treated *** highest dose of TBBPA also caused thyroid histological alteration but had no effects on cerebellar development in terms of Purkinje cell morphology and the thickness of the internal granular layer and the molecular layer of the *** puberty and adulthood,the thyroid morphological alterations became more pronounced in the TBBPA-treated animals,accompanied by decreased serum thyroid hormone ***,the 50 and 500μg/(kg·day)TBBPA groups showed a significant decrease in the serum level of serotonin,a neurotransmitter associated with anxiety ***,the highest dose group displayed anxiety-like behaviors in the elevated plus-maze test on PND 35,but this neurobehavioral alteration disappeared on PND ***,no changes in neurobehavioral parameters tested were found in TBBPAtreated animals at puberty and ***,all observations show that TBBPA can exert thyroid disrupting effects but has little overt impact on brain development and neurobehaviors in mice,suggesting that thyroid disruption does not necessarily cause overtly adverse neurodevelopmental outcomes.

关键词： Tetrabromobisphenol A Thyroid disruption Brain development Neurobehavior Cerebellum