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Magnetoelectric effects in multiferroic laminated plates with imperfect interfaces

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Theoretical & Applied Mech.nics Letters 2017年第2期7卷 93-99页

作者： DJ. Kong C. Ruan-Wu Y.X. Luo C.L. zhang ch. zhang Zhejiang Tongji Vocational College of Sdence and Tech.ology Hangzhou 311231 China Department of Engineering Mech.nics Zhejiang University Hangzhou 310027 China Escuela Tecnica Superior de Ingenieros Aeronautios Universidad Politecnica de Madrid Madrid 28040 Spain Key Laboratory of Soft Mach.nes and Smart Devices of Zhejiang Province Hangzhou 310027 China Department of Civil Engineering University of Siegen Siegen D-57068 Germany

Two-dimensional （2D） equations for multiferroic （MF） laminated plates with imperfect interfaces are established in this paper. The interface between two adjacent sublayers, which.are not perfectly bonded together, is modeled as a general spring-type layer. The mech.nical displacements, and the electric and magnetic potentials of the two adjacent layers are assumed to be discontinuous at the interface. As an example, the influences of imperfect interfaces on the magnetoelectric （ME） coupling effects in an MF sandwich.plate are investigated with the established 2D governing equations. Numerical results show that the imperfect interfaces have a significant impact on the ME coupling effects in MF laminated structures.

关键词： Multiferroic laminated plates Two-dimensional equations Imperfect interfaces Magnetoelectric coupling effects

Bile acids,gut microbiota,and therapeutic insights in hepatocellular carcinoma

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Cancer Biology & Medicine 2024年第2期21卷 144-162页

作者： Yang Song Harry ch.Lau Xiang zhang Jun Yu Institute of Digestive Disease and Department of Medicine and Therapeutics State Key Laboratory of Digestive DiseaseLi Ka Shing Institute of Health SciencesCUHK Shenzhen Research InstituteThe Chinese University of Hong KongHong KongChina Department of Gastroenterology Zhongshan Hospital Xiamen UniversityXiamen 361004China

Hepatocellular carcinoma(HCC)is a prevalent and aggressive liver *** interplay between bile acids(BAs)and the gut microbiota has emerged as a critical factor in HCC development and *** normal conditions,BA metabolism is tightly regulated through a bidirectional interplay between gut microorganisms and *** gut microbiota plays a critical role in BA metabolism,and BAs are endogenous signaling molecules that help maintain liver and intestinal *** note,dysbiotic ch.nges in the gut microbiota during pathogenesis and cancer development can disrupt BA homeostasis,thereby leading to liver inflammation and fibrosis,and ultimately contributing to HCC ***,understanding the intricate interplay between BAs and the gut microbiota is crucial for elucidating the mech.nisms underlying *** this review,we comprehensively explore the roles and functions of BA metabolism,with a focus on the interactions between BAs and gut microorganisms in ***,therapeutic strategies targeting BA metabolism and the gut microbiota are discussed,including the use of BA agonists/antagonists,probiotic/prebiotic and dietary interventions,fecal microbiota transplantation,and engineered *** summary,understanding the complex BA-microbiota crosstalk can provide valuable insights into HCC development and facilitate the development of innovative therapeutic approach.s for liver malignancy.

关键词： Bile acid gut microbiota hepatocellular carcinoma therapeutics microbiota modulation

One-cycles on Gushel-Mukai fourfolds and the Beauville-Voisin filtration

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Science ch.na Mathematics 2024年第4期67卷 713-732页

作者： Ruxuan zhang Sch.ol of Mathematical Sciences Fudan UniversityShanghai 200438China

We prove that the invariant locus of the involution associated with a general double EisenbudPopescu-Walter(EPW)sextic is a constant cycle surface and introduce a filtration on ch.of a Gushel-Mukai *** verify the sheaf/cycle correspondence for sheaves supported on low-degree rational curves,parallel to the case of cubic fourfolds of Shen-Yin’s work.

关键词： Beauville-Voisin ltration irreducible holomorphic symplectic variety Gushel-Mukai fourfold

PROGRESS OF SYNTHETIC APERTURE SONAR IN ch.NA

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PROGRESS OF SYNTHETIC APERTURE SONAR IN CHINA

Initial precursor reaction mech.nism of CVD-HfC coating based on density functional theory

2002中国—日本声学学术会议

作者： J. Tang ch. zhang Sh. Li B. Sun J. Liu J. Xu Y. Huang T. Lin Sh. Xue L. Li T. Cui H. Huang Y. Li Q. Li Institute of Acoustics ch.nese Academy of Science 17 Zhongguancun St. Beijing PRC

The Project of synthetic aperture sonar in ch.na started in 1997. Up to now, we have built a prototype of synthetic aperture sonar for lake trial. It is of multi elements, so it can work in high speed

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来源： cnki会议评论

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ch.nese Journal of Aeronautics 2024年第7期37卷 511-521页

作者： Yunzhou LIN Yulei zhang Yanqin FU Jian zhang Jing’an KONG Ruicong ch.N State Key Laboratory of Solidification Processing Carbon/Carbon Composites Research CenterNorthwestern Polytechnical UniversityXi’an 710072China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Carbon Matrix Composites Research InstituteHenan Academy of SciencesZhengzhou 450046China

Recently,the preparation of ultra-high temperature HfC ceramic coating has gained significant attention,particularly through the application of the HfCl_(4)-ch.(4)-H_(2)-Ar system via ch.mical Vapor Deposition(CVD),which.has been found widely applied to C/C ***,an analysis of the reactions that occur in the initial stage of the CVD-HfC coating process is presented using Density Functional Theory(DFT)and Transition State Theory(TST)at the B3LYP/Lanl2DZ *** results reveal that HfCl4 can only cleave to produce hypoch.orite,which.will further react with methyl to synthesize intermediates to form *** to the analysis of the energy barrier and reaction constant,HfCl preferentially reacts with methyl groups to form complex adsorptive intermediates at 1573 *** a C—Hf bond production energy of 212.8 kcal/mol(1 kcal=4.18 kJ),the reaction rate constant of HfCl+ch.is calculated to be 2.15×10^(-18) cm^(3)/s at 1573 ***,both the simulation and experimental results exhibit that the upward trend of reaction rate constants with temperature is also consistent with the deposition rate,indicating that the growth curve of the reaction rate constants tends to flatten *** proposed reaction model of the precursor’s decomposition and reconstruction during deposition process has significant implication for the process guidance.

关键词： Carbon composite HfC coating ch.mical vapor deposition Density functional theory Precursor reaction mech.nism

Magnetism of NaYbS_(2):From finite temperatures to ground state

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Science ch.na(Physics,Mech.nics & Astronomy) 2024年第10期67卷 92-104页

作者： Weizhen Zhuo Zheng zhang Mingtai Xie Anmin zhang Jianting Ji Feng Jin Qingming zhang Sch.ol of Physical Science and Tech.ology Lanzhou UniversityLanzhou 730000China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Rare-earth ch.lcogenide compounds AREch.(2)(A=alkali or monovalent metal,RE=rare earth,ch.O,S,Se,Te)are a large family of quantum spin liquid(QSL)candidate ***2is a representative member of the *** key issues on NaYbS_(2),particularly how to determine the highly anisotropic spin Hamiltonian and describe the magnetism at finite temperatures and the ground state,remain to be *** this paper,we conducted an in-depth and comprehensive study on the magnetism of NaYbS_(2) from finite temperatures to the ground ***,we successfully detected three crystalline electric field(CEF)excitation energy levels using low-temperature Raman scattering *** them with the CEF theory and magnetization data,we worked out the CEF parameters,CEF energy levels,and CEF *** further determined a ch.racteristic temperature of~40 K,above which.the magnetism is dominated by CEF excitations while below which.the spinexch.nge interactions play a main *** ch.racteristic temperature has been confirmed by the temperature-dependent electron spin resonance(ESR)***-temperature ESR experiments on the dilute magnetic doped crystal of NaYb_(0.1)Lu_(0.9)S_(2) further helped us to determine the accurate ***,we quantitatively obtained the spin-exch.nge interactions in the spin Hamiltonian by consistently simulating the magnetization and specific heat ***,the above studies allow us to explore the ground state magnetism of NaYbS_(2) by using the density matrix renormalization *** combined numerical calculations and experimental results to demonstrate that the ground state of NaYbS_(2) is a Dirac-like QSL.

关键词： rare-earth ch.lcogenide anisotropic spin Hamiltonian quantum spin liquid

Compositional evolution for mixed aerosols containing gluconic acid and typical nitrate and the effect of multiply factors on hygroscopicity

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Journal of Environmental Sciences 2024年第5期139卷 206-216页

作者： Yue Zhu Shufeng Pang Yunhong zhang Sch.ol of ch.mistry and ch.mical Engineering Beijing Institute of TechnologyBeijing 100081China

The aging process of atmospheric aerosols usually leads to a mixture of inorganic salts and organic compounds of anthropogenic *** organic compounds,polyhydroxy organic acids are important components,however,the study on composition and hygroscopic properties of the mixture containing inorganics and polyhydroxy organic acids is *** this study,gluconic acid,the proxy of polyhydroxy organic acids,is mixed with the representative nitrate(Mg(NO_(3))_(2),Ca(NO_(3))_(2))to form ***-FTIR and optical microscopy are employed to study the component ch.nges and hygroscopicity as a function of relative *** relative humidity fluctuates,the FTIR-ATR spectra display that the internal mixed gluconic acid(ch.(2)(ch._(4)(OH)_(5)COOH)and nitrate can react to release acidic gases,forming relevant gluconate and further affecting the *** specific presentation is particles cannot be recovered to their original size after the dehydration-hydration process and there will be some disparities in GF for mixed *** the gluconic acid-Ca(NO_(3))_(2)/Mg(NO_(3))_(2)mixtures with molar ratios of 1:1,higher degree of reaction resulting in the production of large amounts of gluconate should be responsible to the lower hygroscopicity compared to ZSR *** 1:2 gluconic acid-nitrate mixed systems(with higher nitrate content),the hygroscopicity of mixtures are higher than the ZSR prediction.A possible reason could be‘salt-promoting effect’on the organic fractions of the surplus inorganic salt in the *** data can improve the ch.mical composition list evaluation,in turn hygroscopic properties and phase state of atmospheric aerosol,and then the climate effect.

关键词： Hygroscopicity Gluconic acid Reaction ZSR simulation Size growth factors

Significant contribution of carbonyls to atmospheric oxidation capacity(AOC)during the winter haze pollution over North ch.na Plain

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Journal of Environmental Sciences 2024年第5期139卷 377-388页

作者： Xue Yang Gen zhang Guang Pan Guolan Fan Houyong zhang Xuan Ge Mingyue Du Sch.ol of Municipal and Environmental Engineering Shandong Jianzhu UniversityJi’nan 250101China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric ch.mistry of ch.na Meteorological Administration Chinese Academy of Meteorological SciencesBeijing 100081China Shandong Jinan Ecological Environment Monitoring Center Ji’nan 250101China

Atmospheric carbonyl compounds play significant roles in the cycling of radicals and have exhibited surprisingly high levels in winter that were well correlated to particulate matter,for which.the reason have not been clearly *** we measured carbonyl compounds and other trace gasses together with PM_(2.5)over urban Jinan in North ch.na Plain during the *** higher carbonyl concentrations(average:14.63±4.21 ppbv)were found during wintertime haze pollution,about one to three-times relative to those on nonhaze days,with slight difference in ch.mical composition except formaldehyde(Hch.).Hch.(3.68 ppbv),acetone(3.17 ppbv),and acetaldehyde(ch.3ch.)(2.83 ppbv)were the three most abundant species,accounting for~75% of the total carbonylson both haze and non-haze *** from observational-based model(OBM)with atmospheric oxidation capacity(AOC)indicated that AOC significantly increased with the increasing carbonyls during the winter haze *** photolysis have supplied key oxidants such.as RO_(2) and HO_(2),and thereby enhancing the formation of fine particles and secondary organic aerosols,elucidating the observed haze-carbonyls *** variation with carbonyls exhibiting peak values at early-noon and night highlighted the combined contribution of both secondary formation and primary diesel-fuel sources.1-butene was further confirmed to be the major precursor for *** study confirms the great contribution of carbonyls to AOC,and also suggests that reducing the emissions of carbonyls would be an effective way to mitigate haze pollution in urban area of the NCP region.

关键词： Carbonyls Haze Observation-based model Source apportionment Atmospheric oxidation capacity

Nanoscale materials transformations revealed by liquid phase TEM

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Nano Research 2024年第10期17卷 9152-9165页

作者： Qiubo zhang Daewon Lee Haimei Zheng Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCalifornia 94720USA Department of Materials Science and Engineering University of CaliforniaBerkeleyCalifornia 94720USA

Nanoscale materials often undergo structural,morphological,or ch.mical ch.nges,especially in solution processes,where heterogeneity and defects may significantly impact the transformation *** phase transmission electron microscopy(TEM),allowing us to track dynamic transformations of individual nanoparticles,has become a powerful platform to reveal nanoscale materials transformation pathways and address ch.llenging issues that are hard to approach.by other *** the development of modern liquid cells,implementing advanced imaging and image analysis methods,and strategically exploring diverse systems,significant advances have been made in liquid phase TEM,including improved high-resolution imaging through liquids at the atomic level and remarkable capabilities in handling complex systems and *** the past more than a decade,we spent much.effort in developing and applying liquid phase TEM to elucidate how atomic level heterogeneity and defects impact various physicoch.mical processes in liquids,such.as growth,self-assembly of nanoparticles,etch.ng/corrosion,electrodeposition of alkali metals,catalyst restructuring during reactions,and so *** article provides a brief review of the liquid phase TEM study of nanoscale materials transformations,focusing on the growth of nanomaterials with distinct shape/hierarch.cal structures,such.as one-dimensional(1D)growth by nanoparticle attach.ent,two-dimensional(2D)growth with nanoparticles as intermediates,core-shell structure ripening,solid-liquid interfaces including those in batteries and electrocatalysis,highlighting the impacts of heterogeneity and defects on broad nanoscale transformation pathways.

关键词： liquid phase transmission electron microscopy(TEM) liquid cells nanomaterials growth transformations pathways solid-liquid interface heterogeneity and fluctuations