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A Nonlinear Magneto-Mechanical Coupled Constitutive Model for the Magnetostrictive Material Galfenol

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Computers, Materials & Continua 2018年第3期54卷 209-228页

作者： Ying Xiao Haomiao Zhou xiaofan Gou College of Information Engineering China Jiliang UniversityHangzhou310018P.R.China College of Mechanics and Materials Hohai UniversityNanjing210098P.R.China

In order to predict the performance of magnetostrictive smart material and pushits applications in engineering, it is necessary to build the constitutive relations for themagnetostrictive material Galfenol. For Galfenol rods under the action of the pre-stress andmagnetic field along the axial direction, the one-dimensional nonlinear magneto-mechanicalcoupling constitutive model is proposed based on the elastic Gibbs free energy, where theTaylor expansion of the elastic Gibbs free energy is made to obtain the polynomial forms. Andthen the constitutive relations are derived by replacing the polynomial forms with the propertranscendental functions based on the microscopic magneto-mechanical coupling *** the perspective of microscopic mechanism, the nonlinear strain related to magneticdomain rotation results in magnetostrictive strain changing with the pre-stress among theelastic strains induced by the pre-stress. By comparison, the predicted stress-strain,magnetostrictive strain, magnetic induction and magnetization curves agreed well withexperimental results under the different pre-stresses. The proposed model can describe notonly the influences of pre-stress on magnetostrictive strain and magnetization curves, butalso nonlinear magneto-mechanical coupling effect of magnetostrictive materialsystematically, such as the young’s modulus varying with stress and magnetic field. In theproposed constitutive model, the key material constants are not chosen to obtain a good fitwith the experimental data, but aremeasured directly by experiments, such as the saturationmagnetization, saturation magnetostrictive coefficient, saturation young’s modulus, linearmagnetic susceptibility and so on. In addition, the forms of the new constitutive relationsare simpler than the existing constitutive models. Therefore, this model could be appliedconveniently in the engineering applications.

关键词： Magnetostrictive materials one-dimensional constitutive relations galfenolrods nonlinear magneto-mechanical coupling

AIE interfacial supramolecular polymers

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Chinese Chemical Letters 2024年第1期35卷 316-320页

作者： Qingyun Li Ziqing Hu xiaofan Ji Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China

High monomer concentration is a requisite for engendering the aggregation-induced emssion(AIE)phenomenon as well as the formation of supramolecular ***,this is supposed to ensure the generation of AIE supramolecular polymers,wherein the monomer soluability takes ***,parts of supramolecular monomers are considered as poessessing different soluability towards the same sovlent,through which the polymerzation process is thus hard to *** polymerzation gets over the soluabilty restriction,providing a facile method for propelling the reaction of ***,we had prepared M1 containing tetraphenylethene(TPE)functionalized with two terpyridine derivatives,then making M1 dissolving in CHCl3 to give ***^(2+)solutions were fabricated through dissolving CuCl_(2)into *** mixing those solutions,AIE interfacial supramolecular polymers(AIEISPs)displaying green fluorescence were generated at the interface of two phases on the basis of metal-coordination between terpyridine and Cu^(2+).These AIEISPs were certificated to possess the stimuli-responsiveness,for which the excessive addition of tetrabutylammonium hydroxide would cause the structure destruction owing to the stronger bonding ability with Cu^(2+)than that of *** fabricated AIEISPs had provided a new avenue to prepare AIE supramolecular polymers.

关键词： Aggregation-induced emission Interfaces Metal-coordination interactions Supramolecular polymers Stimuli-responsiveness

Theoretical analysis of the confidence metrics for nearestneighbor classifier

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Chinese Science Bulletin 1998年第6期43卷 464-467页

作者： xiaofan Lin Xiaoqing Ding youshou Wu Tsing Hua Univ Dept Elect Engn Beijing 100084 Peoples R China

Confidence value plays a vital role in the decision of rejection threshold and the integration of multiple classifiers. Nearest neighbor (NN) classifier is the most traditional and most common nonparameter statistical pattern classifier. However, so far there is no explicate theoretical analysis of the connection between nearest distance and confidence value. An analytical insight into different approximations is presented and one formula is pointed out that it is optimal in the sense of mathematical expectation. Practice in handwritten numeral recognition strongly supports the conclusion.

关键词： nearest neighbor classifier confidence value optimal rejection handwritten numeral recognition.

Genome-wide Analysis of Kelch Repeatcontaining F-box Family

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Journal of Integrative Plant Biology 2007年第6期49卷 940-952页

作者： Yujin Sun xiaofan Zhou Hong Ma Department of Biology and the Huck Institutes of Life Sciences Intercollege Graduate Program in Cell and Developmental Biology The Pennsylvania State University University Park PA 16802 USA

The ubiquitin-dependent protein degradation pathway plays diverse roles in eukaryotes. Previous studies indicate that both F-box and Kelch motifs are common in a variety of organisms. F-box proteins are subunits of E3 ubiquitin ligase complexes called SCFs （SKP1, Cullinl, F-box protein, and Rbxl）; they have an N-terminal F-box motif that binds to SKP1 （S-phase kinase associated protein）, and often have C-terminal protein-protein interaction domains, which specify the protein substrates for degradation via the ubiquitin pathway. One of the most frequently found protein interaction domains in F-box proteins is the Kelch repeat domain. Although both the F-box and Kelch repeats are ancient motifs, Kelch repeats-containing F-box proteins （KFB） have only been reported for human and Arabidopsis previously. The recent sequencing of the rice genome and other plant genomes provides an opportunity to examine the possible evolution history of KFB. We carried out extensive BLAST searches to identify putative KFBs in selected organisms, and analyzed their relationships phylogenetically. We also carried out the analysis of both gene duplication and gene expression of the KFBs in rice and Arabidopsis. Our study indicates that the origin of KFBs occurs before the divergence of animals and plants, and plant KFBs underwent rapid gene duplications.

关键词： Arabidopsis thaliana F-box motif Kelch repeats Kelch repeats-containing F-box proteins SCF SKP1 like.

A New Bromophenol from the Brown Alga Leathesia nana

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Chinese Chemical Letters 2004年第6期15卷 661-663页

作者： XiuLiXU xiaofan FuHangSONG JieLuZHAO LiJunHAN JianGongSHI InstituteofOceanology ChineseAcademyofSciencesQingdao266071 GraduateSchooloftheChineseAcademyofSciences Beijing100039 InstituteofMateriaMedica ChineseAcademyofMedicalSciencesandPekingUnionMedicalCollegeBeijing100050

A novel bromophenol was isolated from ethanolic extract of the brown alga Leathesia nana *** G. The structure was elucidated as (E)-3-(2,3-dibromo-4,5-dihydroxyphenyl)-2-methyl-propenal by spectroscopic methods includ... 详细信息

关键词： Brown alga Leathesiaceae Leathesia nana bromophenol.

A Modeling Study of Diurnal Rainfall Variations during the 21-Day Period of TOGA COARE

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Advances in Atmospheric Sciences 2009年第5期26卷 895-905页

作者：高守亭崔晓鹏 xiaofan LI Laboratory of Cloud-Precipitation Physics and Severe Storms （ LACS） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 Joint Center for Satellite Data Assimilation and NOAA/NESDIS/Center for Satellite Applications and Research Camp Springs Maryland USA

The surface rainfall processes and diurnal variations associated with tropical oceanic convection are examined by analyzing a surface rainfall equation and thermal budget based on hourly zonal-mean data from a series of two-dimensional cloud-resolving simulations. The model is integrated for 21 days with imposed large-scale vertical velocity, zonal wind, and horizontal advection obtained from the Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment （TOGA COARE） in the control experiment. Diurnal analysis shows that the infrared radiative cooling after sunset, as well as the advective cooling associated with imposed large-scale ascending motion, destabilize the atmosphere and release convective available potential energy to energize nocturnal convective development. Substantial local atmospheric drying is associated with the nocturnal rainfall peak in early morning, which is a result of the large condensation and deposition rates in the vapor budget. Sensitivity experiments show that diurnal variations of radiation and large-scale forcing can produce a nocturnal rainfall peak through infrared and advective cooling, respectively.

关键词： diurnal rainfall variation cloud-resolving simulation tropical oceanic convection TOGACOARE

EXTREMA OF A GAUSSIAN RANDOM FIELD:BERMAN'S SOJOURN TIME METHOD

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Acta Mathematica Scientia 2022年第5期42卷 1831-1842页

作者： Liwen CHEN xiaofan PENG School of Mathematical Sciences University of Electronic Science and Technology of ChinaChengdu 611731China

In this paper we devote ourselves to extending Berman’s sojourn time method,which is thoroughly described in[1-3],to investigate the tail asymptotics of the extrema of a Gaussian random field over[0,T]^(d) with T∈(0... 详细信息

关键词： tail asymptotics sojourn time Gaussian random field extreme stationarity

Responses of Vertical Structures in Convective and Stratiform Regions to Large-Scale Forcing during the Landfall of Severe Tropical Storm Bilis (2006)

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Advances in Atmospheric Sciences 2010年第1期27卷 33-46页

作者：王东海 xiaofan LI Wei-Kuo TAO State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 Science System and Applications Inc. Lanham MD USA NOAA/NESDIS//Center for Satellite Applications and Research Camp Springs MD USA NASA/Goddard Space Flight Center Greenbelt MD USA

The responses of vertical structures, in convective and stratiform regions, to the large-scale forcing during the landfall of tropical storm Bilis （2006） are investigated using the data from a two-dimensional cloud-resolving model simulation. An imposed large-scale forcing with upward motion in the mid and upper troposphere and downward motion in the lower troposphere on 15 July suppresses convective clouds, which leads to -100% coverage of raining stratiform clouds over the entire model domain. The imposed forcing extends upward motion to the lower troposphere during 16-17 July, which leads to an enhancement of convective clouds and suppression of raining stratiform clouds. The switch of large-scale lower-tropospheric vertical velocity from weak downward motion on 15 July to moderate upward motion during 16-17 July produces a much broader distribution of the vertical velocity, water vapor and hydrometeor fluxes, perturbation specific humidity, and total hydrometeor mixing ratio during 16-17 July than those on 15 July in the analysis of contoured frequency-altitude diagrams. Further analysis of the water vapor budget reveals that local atmospheric moistening is mainly caused by the enhancement of evaporation of rain associated with downward motion on 15 July, whereas local atmospheric drying is mainly determined by the advective drying associated with downward motion over raining stratiform regions and by the net condensation associated with upward motion over convective regions during 16-17 July.

关键词： cloud-resolving simulation large-scale vertical velocity water vapor and hydrometeor mass fluxes heat budgets

A New Sesquiterpene-substituted Benzoic Acid from the Brown Alga Dictyopteris divaricata

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Chinese Chemical Letters 2004年第3期15卷 316-318页

作者： FuHangSONG xiaofan XiuLiXU JieLuZHAO LiJunHAN JianGongSHI InstituteofOceanology ChineseAcademyofSciencesQingdao266071 GraduateSchooloftheChineseAcademyofSciences Beijing100039 InstituteofMateriaMedica ChineseAcademyofMedicalSciencesandPekingUnionMedicalCollegeBeijing100050

A new sesquiterpene-substituted benzoic acid has been isolated from the brown Alga Dictyopteris divaricata Okam.. Its structure was elucidated as 3-[(2-hydroxy-2,5,5,8a-tetra- methyldecahydro-1-naphthalenyl)methyl]-4-hydroxybenzoic acid, named dictyvaric acid on the basis of spectroscopic methods including IR, HRFABMS, 1D and 2D NMR techniques.

关键词： Brown alga Dictyopteris divaricata 3-[(2-hydroxy-2,5,5,8a-tetramethyl-decahydro-1- naphthalenyl)-methyl]-4-hydroxybenzoic acid dictyvaric acid.