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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 220-226页

作者： f. chai c.f. yang H. Su Y.Q. Zhang Z. Xu Y.H. yang Institute for Structural Materials Central Iron and Steel Research Institute Beijing 100081 China School of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200030 China School of Materials Science and Engineering Kunming University of Science and Technology Kunming650093 China

Effects of Zirconium on the chemical component and size distribution of Ti-bearing inclusions, favored the grain refinement of the welding reduced, coarse-grained heat affected zone （cGHAZ） with enhanced impact toughness in Ti-killed steels, which were examined based on experimental observations and thermodynamic calculations. It indicated that the chemical constituents of inclusions gradually varied from the TiO oxide to the Ti-O＋Zr-O compound oxide and a single phase of the ZrO2 oxide, as the Zr content increased from zero to 0.0100%. A trace of Zr （0.0030%-0.0080%, depending on the oxygen content in liquid steel） provided a large amount of nucleating core for Ti oxide because of the larger spec.f.c density of ZrO2 oxide, and produced a small size distribution of the inclusions favorable for acicular ferrite transformation with a high nucleation rate in the cGHAZ, and a high volume fraction of acicular ferrite was obtained in the cGHAZ, with enhanced impact toughness. Otherwise, a high content of Zr （-0.0100%） produced a single phase Zr02, which was impotent to nucleate acicular ferrite, and a microstructure composed of ferrite side plate and grain boundary ferrite developed in the cGHAZ. The experimental results were confirmed by thermodynamic calculations.

关键词： Nonmetallic inclusions Zirconium Acicular ferrite coarse-grain heat affected zone (cGHAZ)

Enhanced thermal conductivity and mechanical properties of 2D c_(f)/Sic composites modified by in-situ grown carbon nanotubes

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Journal of Advanced ceramics 2024年第1期13卷 19-33页

作者： changhui Niu Qing Zhang Laifei cheng fang Ye Litong Zhang Min Huang Tao yang Science and Technology on Thermostructure composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China civil Aviation Department Zhejiang Institute of CommunicationsHangzhou 311112China Zhejiang Provincial Key Laboratory for cutting Tools Taizhou UniversityTaizhou 318000China

In this work,the effects of carbon nanotubes(cNTs)on the microstructure evolution,thermal conductivity,and mechanical properties of c_(f)/Sic composites during chemical vapor infiltration(cVI)densification were investigated in *** with composites without cNTs,the thermal conductivity,flexural strength,flexural modulus,fracture toughness,interfacial shear strength,and proportional limit stress of specimens with cNTs of 4.94 wt%were improved by 117%,21.8%,67.4%,10.3%,36.4%,and 71.1%,*** improvement was attributed to the role of cNTs in the division of inter-layer pores,which provided abundant vapor growth sites for the ceramic matrix and promoted densification of the whole *** addition,the high thermal conductivity network formed by the overlap of cNTs and the rivet strengthening effect of cNTs were beneficial for synergistic improvement of thermal conductivity and mechanical properties of the ***,this study has practical significance for the development of thermal protection composite components with enhanced thermal conductivity and mechanical characteristics.

关键词： ceramic−matrix composites carbon nanotubes microstructure thermal conductivity mechanical properties

Asymmetric alkenylation reaction of benzoxazinones with diarylethylenes catalyzed by B(c_(6)f_(5))_(3)/chiral phosphoric acid

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chinese chemical Letters 2024年第5期35卷 135-140页

作者： Zhen Liu Zhi-Yuan Ren chen yang Xiangyi Shao Li chen Xin Li State Key Laboratory of Elemento-Organic chemistry Frontiers Science Center for New Organic MatterCollege of ChemistryNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable chemical Transformations Tianjin 300192China Zhenhai High School of Zhejiang Ningbo 315299China

catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules,but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive ***,we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(c_(6)f_(5))_(3)/chiral phosphoric acid catalyst.A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated(up to 95%yield and 97.5:2.5 e.r.)in the methodology under mild reaction ***,the synthetic utility was confirmed by the scaled-up reaction and transformations of the *** mechanism was preliminarily explored by control reactions,nonlinear effect experiment and DfT calculations.

关键词： Asymmetric alkenylation Simple alkenes Benzoxazinones B(c_(6)f_(5))_(3)/chiral phosphoric acid Theoretical calculations

cognition on oxidation behavior of Ni-based superalloy GH4742 when exposed to water vapor

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Journal of Materials Science & Technology 2024年第7期174卷 15-22页

作者： H.Xu S.f.yang E.H.Wang c.Y.Guo Y.S.Liu X.M.Hou Y.L.Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Institute for carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The oxidation behavior of Ni-based superalloy GH4742 exposed to water vapor was investigated at 900-1100℃for 50 h in Ar+20%H_(2)O,with Ar+20%O_(2)included for *** presence of H_(2)O is adverse to formation of continuous cr_(2)O_(3)oxide layer but contributes to generation of big *** on this,Ni^(2+)and co^(2+)are more easily to diffuse towards the outermost oxide layer(OOL),forming non-protective Ni-and co-rich oxides with high *** leads to a higher weight gain in Ar+20%H_(2)O than that in Ar+20%O_(2).At elevated temperatures,the spallation of oxide scale occurs while the consumption of cr is reduced in Ar+20%H_(2)O,and the contents of Ni-and co-rich oxides at this moment are reduced in the *** oxidation mechanism was also discussed.

关键词： GH4742 Superalloy H_(2)O Diffusion Oxidation Mechanism

All-electron basis sets for H to Xe spec.f.c.f.r ZORA calculations:Applications in atoms and molecules

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chinese Physics B 2024年第8期33卷 238-246页

作者： c.S.Gomes f.E.Jorge A.canal Neto Departamento de fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZORA-ccSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe ccSD(T)method atomic and molecular properties

Regulating interfacial chemistry and kinetic behaviors of f/Mo co-doping Ni-rich layered oxide cathode for long-cycling lithium-ion batteries over-20°c-60°c

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Journal of Energy chemistry 2024年第7期94卷 449-457页

作者： Siqi Guan Lin Tao Pei Tang Ruopian fang Huize Wu Nan Piao Huicong yang Guangjian Hu Xin Geng Lixiang Li Baigang An feng Li Institute of Energy Materials and Electrochemistry Research University of Science and Technology LiaoningAnshan 114051LiaoningChina Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016LiaoningChina Shenyang King Power Tech.co. Ltd.Shenyang 110016LiaoningChina School of chemical Engineering The University of New South WalesSydney 2052NSWAustralia

Ni-rich layered oxide cathodes have shown promise for high-energy lithium-ion batteries(LIBs)but are usually limited to mild environments because of their rapid performance degradation under extreme temperature conditions(below0°c and above 50 °c).Here,we report the design of f/Mo co-doped LiNi_(0.8)co_(0.1)Mn_(0.1)O_(2)(fMNcM)cathode for high-performance LIBs from-20 to 60°c.f.(-) doping with high electronegativity into the cathode surface is found to enhance the stability of surface lattice structure and protect the interface from side reactions with the electrolyte by generating a Lif-rich surface ***,the Mo^(6+) doping suppresses phase transition,which blocks Li^(+)/Ni^(2+) mixing,and stabilizes lithium-ion diffusion ***,the fMNcM cathode demonstrates excellent cycling stability at a high cutoff voltage of 4.4 V,even at 60°c,maintaining 90.6%capacity retention at 3 c after 150 ***,at temperatures as low as-20°c,it retains 77.1%of its room temperature capacity,achieving an impressive 97.5%capacity retention after 500 *** stable operation under wide temperatures has been further validated in practical Ah-level *** study sheds light on both fundamental mechanisms and practical implications for the design of advanced cathode materials for wide-temperature LIBs,presenting a promising path towards high-energy and long-cycling LIBs with temperatureadaptability.

关键词： Anion-cation co-doping Wide temperature operation Ni-richlayered cathode Phase transition Surface/interface

Effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of coal Science & Technology 2024年第3期11卷 86-101页

作者： f.Animah c.Keles W.R.Reed E.Sarver Department of Mining and Minerals Engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(cAcs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter cAc on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and cAc appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three spec.f.c dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： Respirable dust Dust control SEM–EDX Scrubber canopy air curtain Silica

An organic.f.ee radical generator independent on hydrogen peroxide for chemodynamic and immunotherapy in vivo

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Journal of Materials Science & Technology 2024年第7期174卷 85-94页

作者： yang chen Yunpeng Song chaojie Tang Hong yang Wu Wang Shiping yang Zhiguo Zhou college of chemistry and Materials Science International Joint Laboratory on Resource Chemistry of Ministry EducationShanghai Frontiers Science Center of Biomimetic CatalysisShanghai Normal UniversityShanghai 200234China Institute of Diagnostic and Interventional Radiology Shanghai Jiao Tong University Affiliated Sixth People’s HospitalShanghai 200233China

It is desirable to develop a free radical generator that is neither dependent on hydrogen peroxide nor external stimuli-triggered to achieve effective tumor ***,the free radical genera-tor MNPs-mcPBA was constructed with Zn_(0.4)co_(0.6)f_(e2)O_(4)@Zn_(0.4)Mn_(0.6)fe_(2)O_(4)nanoparticles(MNPs)and 3-chloroperbenzoic acid(mcPBA).We believe that the iron(Ⅱ)on the surface of MNPs-mcPBA maybe represent high reactive activity and promote the generation of a large number of organic.f.ee radicals(c_(6)H_(4)clcOOO)in an acidic tumor microenvironment,which realizes the acid-dependent tumor treat-ment strategy independent on the H_(2)O_(2)level in *** addition,the generated organic.f.ee radicals(c_(6)H_(4)clcOOO)effectively induced immunogenic cell death(IcD)and increased T cell ***-der the synergetic treatment with an anti-PD-L1 antibody(α-PD-L1),a favorable anti-tumor effect was achieved.

关键词： Organic.f.ee radicals Immunogenic cell death Immunotherapy chemodynamic therapy

Mathematical modeling and simulations of stress mitigation by coating polycrystalline particles in lithium-ion batteries

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 947-962页

作者： N.IQBAL J.cHOI S.f.SHAH c.LEE S.LEE Department of Mechanical Roboticsand Energy EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline Ni-rich LiNixMnyco_(z)O_(2)(x≥0.8)(NMc)particles with poly(3,4-ethylenedioxythiophene)(PEDOT).The simulation results show that the coating of primary NMc particles significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more ***,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress *** paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of NMc active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating finite element simulation Ni-rich LiNixMnyco_(z)O_(2)(x>0.8)(NMc)

Adsorption of pharmaceutical pollutants on Zncl_(2)-activated biochar from corn cob:Efficiency,selectivity and mechanism

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Journal of Bioresources and Bioproducts 2024年第1期9卷 58-73页

作者： christian f.Varela L.c.Moreno-Aldana Yazmin Yaneth Agámez-Pertuz Department of chemistry National University of ColombiaAv.Carrera 30 No.45-03BogotáD.C.Colombia Department of Biology and chemistry University of the Llanoskm 12 road to Puerto LópezVillavicencioColombia

The occurrence of pharmaceuticals in water bodies and drinking water poses risks for the envi-ronment and human health,thus it is necessary to study methodologies that allow the efficient removal of these *** this work,corn cob-derived biochar was obtained by Zncl_(2)-activation,and subsequent carbonization at 700℃.The effect of contact time,temperature,pH,and initial concentration on the adsorption capacity of acetaminophen(AcE)and amoxicillin(AMX)was determined through batch *** addition,the kinetics,isotherms,and ther-modynamics parameters were *** activated biochar exhibited a maximum adsorp-tion capacity of 332.08 mg/g for AcE and 175.86 mg/g for *** adsorption kinetics and adsorption isotherm of AcE corresponded to the pseudo-second order and Langmuir model,***,pseudo-first-order kinetics and the freundlich isotherm model were well-fitted to AMX *** AcE and AMX co-adsorption had a synergistic effect on AMX but an antagonistic effect on AcE removal,achieving a maximum adsorption capacity of 193.51 and 184.58 mg/g,*** the other hand,fixed-bed column experiments showed that the adsorption capacity depends on the influent concentration,and the breakthrough curve fits the Thomas and Yoon-Nelson *** mechanism adsorption studies showed that surface inter-actions(hydrogen bonding formation and n-𝜋interactions)are the main driving forces for the adsorption process,and pore filling is the rate-limiting *** this way,the prepared biochar exhibits a high potential for the adsorption of pharmaceutical compounds from water.

关键词： Biochar Adsorption Acetaminophen Amoxicillin Wastewater treatment