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Rare Metals 2016年第9期35卷 691-700页

作者： Xiang Chen Yun-Gui Chen Yong-Bo Tang ding-quan xiao College of Engineering and Technology Neijiang Teachers Normal UniversityNeijiang 641002China School of Materials Science and Engineering Sichuan UniversityChengdu 610065China

The effects of the introduction of Ce to La（1-x）CexFe（11.5）Si（1.5） alloys on 1：13 phase formation mechanism,the first-order magnetic phase transition strengthening characteristics,and magnetocaloric property were studied,*** results show that the formation mechanisms of 1：13 and La Fe Si phases in La（1-x）CexFe（11.5）Si（1.5） alloys are the same as those of Ce2Fe（17） and CeFe2 phases in Ce–Fe binary system,*** substitution of Ce in 1：13 phase which is limited can make the first-order magnetic phase transition characteristics strengthen,which can make thermal and magnetic hysteresis increase,the temperature interval of temperatureinduced phase transition decrease,and the critical magnetic field of field-induced magnetic phase transition（HC）increase,*** to the lattice shrink of 1：13phase with the increase in Ce content,the Curie temperatures（TC） show a linear *** maximum change in magnetic entropy gradually increases due to the decrease in temperature interval of temperature-induced phase transition,but the relative cooling capacities are all about80 Jákg-1at magnetic field of 2 T.

关键词： La1-xCexFe1 5Si1 5alloys Short-time annealing Large magnetocaloric effect Magnetocaloric materials

Effects of solidification rate and excessive Fe on phase formation and magnetoclaoric properties of LaFe_(11.6x)Si_(1.4)

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Transactions of Nonferrous Metals Society of China 2017年第9期27卷 2015-2021页

作者： Xiang CHEN Yun-gui CHEN Yong-bai TANG ding-quan xiao College of Physics and Electronic Information Engineering Neijiang Normal University Neijiang 641002 China School of Materials Science and Engineering Sichuan University Chengdu 610065 China

The effects of solidification rate and excessive Fe on phase formation and magnetocaloric properties of LaFe11.6xSi1.4(x=1.1,1.2)were investigated by XRD,SEM and VSM *** XRD results show that the amount of LaFeSi phase in the as-cast melt-spun ribbons prepared by a copper wheel at a speed of10m/s is less than that in the as-cast arc melting buttons with the same x *** annealed melt-spun ribbons contain smaller amount of La(Fe,Si)13(1:13)phase than the corresponding annealed arc melting *** the melt-spun sample has finer crystalline grains ofα-Fe,as indicated by SEM analysis,its crystalline size has not reached ***,the magnetic exchange-coupling between1:13phase andα-Fe phase has not been observed in melt-spun ***,the maximum negative magnetic entropy change(?SMax)and relative cooling power(RCP)of annealed melt-spun ribbons under a field change of0?2T are weaker than those of the corresponding annealed arc melting buttons.

关键词： LaFe11.6xSi1.4 alloy solidification rate microstructure magnetocaloric properties

Origin of high mechanical quality factor in CuO-doped （K, Na）NbO3-based ceramics

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Frontiers of Materials Science 2014年第2期8卷 165-175页

作者： Wen-Feng LIANG ding-quan xiao Jia-Gang WU Wen-Juan WU Jian-Guo ZHU Department of Materials Science Sichuan University Chengdu 610064 China CAEP Key Laboratory of Neutron Physics Mianyang 621900 China Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China

The origin of a high mechanical quality in CuO-doped （K, Na）NbO3-based ceramics is addressed by considering the correlations between the lattice positions of Cu ions and the hardening effect in K0.48Na0.52＋xNbO3-0.01CuO ceramics. The Cu ions simultaneously occupy K/Na and Nb sites of these ceramics with x = 0 and 0.02, only occupy the K/Na site of the ceramics with x= -0.02, and mostly form a secondary phase of the ceramics with x = -0.05. The Cu ions lead to the hardening of ceramics with an increase of Ec and Qm by only occupying the K/Na site, together with the formation of double hysteresis loops in un-poled compositions. A defect model is proposed to illuminate the origin of a high Qm value, that is, the domain stabilization is dominated by the content of relatively mobile O2- ions in the ceramics, which has a weak bonding with CUK/Na defects.

关键词： lead-free piezoelectric ceramic (K, Na)NbO3 (KNN) mechanism of hard-ening effect mechanical quality factor Qm domain stabilization

Effect of SDBS on interfacial electron transfer at the liquid/liquid interface by thin layer method

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Chinese Chemical Letters 2009年第9期20卷 1115-1118页

作者： Xiu Hui Liu Cun Wu Dong Kai Zhang Fu Peng Zhi Zhen ding xiao quan Lu College of Chemistry & Chemical Engineering Northwest Normal University Lanzhou 730070 China

The effect of an adsorbed anionic surfactant sodium dodecyl benzene sulfonate （SDBS） on electron transfer （ET） reaction between ferricyanide aqueous solution and decamethylferrocene （DMFc） located on the adjacent organic phase was investigated for the first time by thin layer method. The adsorption of SDBS at the interface resulted in a decay in the cathodic plateau current of bimolecular reaction with increasing concentrations of SDBS in aqueous phase. However, the rate constant of electron transfer （ket） increased monotonically as the SDBS concentrations increased from 0 to 200 p, moFL. The experimental results showed that SDBS formed patches on the interface and influenced the structure of electrical double layer. 2009 xiao quan Lu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Anionic surfactant Liquid/liquid interface Electron transfer Thin layer method

A brand new green coating technology for realizing the regulation of spherical propellant energy release process

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Defence Technology（防务技术） 2024年第6期36卷 78-94页

作者： Wenhao Fan Yajun ding Zhongliang xiao School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory of Special Energy Materials Nanjing University of Science and TechnologyMinistry of EducationNanjing 210094China

To achieve the controllable release of energy of nitrocellulose-based propellants,this paper combines the cellulose-based nanocomposites aqueous coating(Surelease®-NC)with fluidized bed coating equipment to successfully prepare the coated spherical propellant for the first *** effects of fluidized bed coating temperature,air velocity,flow speed and atomization pressure on the adhesion rate,coating integrity and coating uniformity of the coated spherical propellant were investigated,and the preparation of coated spherical propellant with homogeneous size and structural integrity was achieved for the first *** microscopic morphology,chemical structure,water vapor adsorption behavior,combustion performance,and ageing resistance property of the coated spherical propellant were systematically investigated by,Fourier transforms infrared spectroscopy(FTIR),Micro confocal raman spectrometer,field scanning electron microscopy(SEM),dynamic vapor adsorption techniques,and closed bomb test,confirming the surface core-shell structure and the tightly bonded interfacial structure of coated spherical ***,the coated spherical propellant has good hygroscopic,excellent progressive burning and long storage stability.

关键词： Nanocomposites aqueous coating Fluidized bed coating equipment Coated spherical propellant Controllable release of energy Long storage stability

Chiral multiple-resonance thermally activated delayed fluorescence materials based on chiral spiro-axis skeleton for efficient circularly polarized electroluminescence

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Science China Chemistry 2024年第7期67卷 2257-2264页

作者： Shi-quan Song xiao Han Zhong-Zhong Huo Ching-Fai Yip Xian-Fang Hong Meng-Ning ding You-Xuan Zheng State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of Mesoscopic Chemistry of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chiral luminescence materials have potential applications in the field of three-dimensional displays due to their circularly polarized luminescence(CPL)***,the further development of circularly polarized organic light-emitting diodes(CP-OLEDs)needs to meet the requirements of high efficiency,high color purity,low cost,and high dissymmetry factor(gPLor gEL),chiral multiple resonance thermally activated delayed fluorescence(MR-TADF)materials are considered as candidates in these ***,based on a pair of chiral spirofluorene precursors,two pairs of high-performance chiral MR-TADF emitters((R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB)are developed,which exhibit strong emissions peaking at 491 and 502 nm in toluene with full-width at half-maximum values of 25 and 33 nm,*** addition,small singlet–triplet energy gaps of 0.15 and 0.10 eV with high absolute photoluminescence efficiencies of 95.0%and 96.7%are observed for p-Spiro-DtBuCzB and m-Spiro-DtBuCzB molecules,*** based on p-Spiro-DtBuCzB and m-Spiro-DtBuCzB display high maximum external quantum efficiencies of 29.6%and 33.8%,*** importantly,CP-OLEDs present symmetric circularly polarized electroluminescence spectra with|gEL|factors of 3.36×10^(-4)and 7.66×10^(-4)for devices based on(R/S)-p-Spiro-DtBuCzB and(R/S)-m-Spiro-DtBuCzB enantiomers,respectively.

关键词： chiral spiro-axis skeleton-based material multiple resonance thermally activated delayed fluorescence circularly polarized electroluminescence dissymmetry factor external quantum efficiency

Effect of Ce,Co,B on formation of LaCo_(13)-structure phase in La(Fe,Si)_(13) alloys

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Transactions of Nonferrous Metals Society of China 2014年第3期24卷 705-711页

作者：陈湘陈云贵唐永柏肖定全四川大学材料科学与工程学院成都610065 内江师范学院工程技术学院内江641002

The effect of Ce, Co, and B on the formation of 1：13 phase in La（Fe, Si）13 alloys was investigated by XRD, SEM and EDS. The results show that Co can improve the formation of 1：13 phase in as-cast LaFe11.6-xCoxSi1.4 alloys, but in as-cast and annealed LaFe11.6Si1.4-xCox alloys, it will hamper the formation of 1：13 phase and help the formation of a-Fe（Co, Si） solid solution. Ce2Fel7 phases will form when x reaches a certain value in as-cast and annealed La1-xCexFe11.5Si1.5 alloys. B can improve the formation of 1：13 phase accompanied with Fe2B phase in as-cast LaFe11.6-xBxSi1.4 alloys. B improves the formation of a-Fe solid solution in LaFe11.6Si1.4-xBx alloys, and there is almost only a-Fe in as-cast and annealed LaFe11.6Si0.9B0.5 alloy. In all, the introduction of Co, B, and Ce cannot eliminate the a-Fe phases in corresponding alloys prepared by the high-temperature and short-time annealing process.

关键词： LaFe13-xSix alloys high-temperature and short-time annealing 1:13 phase

Analytical model for predicting time-dependent lateral deformation of geosynthetics-reinforced soil walls with modular block facing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 711-725页

作者： Luqiang ding Chengzhi xiao Feilong Cui School of Civil and Transportation Engineering Hebei University of TechnologyTianjin300401China

To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining *** this study,a general hyperbolic creep model was first introduced to describe the long-term deformation of geosynthetics,which is a function of elapsed time and two empirical parameters a and *** conventional creep tests with three different tensile loads(Pr)were conducted on two uniaxial geogrids to determine their creep behavior,as well as the a-Pr and b-Pr *** test results show that increasing Pr accelerates the development of creep deformation for both ***,a and b respectively show exponential and negatively linear relationships with Pr,which were confirmed by abundant experimental data available in other *** on the above creep model and relationships,an accurate and reliable analytical model was then proposed for predicting the time-dependent d of GRS walls with modular block facing,which was further validated using a relevant numerical investigation from the previous *** evaluation and comparison of the proposed model with six available prediction models were *** a parametric study was carried out to evaluate the effects of wall height,vertical spacing of geogrids,unit weight and internal friction angle of backfills,and factor of safety against pullout on d at the end of construction and 5 years *** findings show that the creep effect not only promotes d but also raises the elevation of the maximum d along the wall ***,the limitations and application prospects of the proposed model were discussed and analyzed.

关键词： Geosynthetics Creep behavior Geosynthetics-reinforced soil(GRS)walls Lateral deformation Analytical model

Sliced Average Variance Estimation for Tensor Data

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 630-655页

作者： Chuan-quan LI Pei-wen xiao Chao YING xiao-hui LIU School of Statistics Jiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013China Biostatistics and Medical Informatics University of Wisconsin MadisonMadison 53726USA

Tensor data have been widely used in many fields,e.g.,modern biomedical imaging,chemometrics,and economics,but often suffer from some common issues as in high dimensional *** to find their low-dimensional latent structure has been of great interest for *** this end,we develop two efficient tensor sufficient dimension reduction methods based on the sliced average variance estimation(SAVE)to estimate the corresponding dimension reduction *** first one,entitled tensor sliced average variance estimation(TSAVE),works well when the response is discrete or takes finite values,but is not■consistent for continuous response;the second one,named bias-correction tensor sliced average variance estimation(CTSAVE),is a de-biased version of the TSAVE *** asymptotic properties of both methods are derived under mild *** and real data examples are also provided to show the superiority of the efficiency of the developed methods.

关键词： tensor data sliced average variance estimation sufficient dimension reduction central subspace

Effects of the initiation position on the damage and fracture characteristics of linear-charge blasting in rock

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 443-451页

作者： Chenxi ding Renshu Yang xiao Guo Zhe Sui Chenglong xiao Liyun Yang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China State Key Lab of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

To study the effects of the initiation position on the damage and fracture characteristics of linear-charge blasting, blasting model experiments were conducted in this study using computed tomography scanning and three-dimensional reconstruction methods. The fractal damage theory was used to quantify the crack distribution and damage degree of sandstone specimens after blasting. The results showed that regardless of an inverse or top initiation, due to compression deformation and sliding frictional resistance, the plugging medium of the borehole is effective. The energy of the explosive gas near the top of the borehole is consumed. This affects the effective crushing of rocks near the top of the borehole, where the extent of damage to Sections Ⅰ and Ⅱ is less than that of Sections Ⅲ and Ⅳ. In addition, the analysis revealed that under conditions of top initiation, the reflected tensile damage of the rock at the free face of the top of the borehole and the compression deformation of the plug and friction consume more blasting energy, resulting in lower blasting energy efficiency for top initiation. As a result, the overall damage degree of the specimens in the top-initiation group was significantly smaller than that in the inverse-initiation group. Under conditions of inverse initiation, the blasting energy efficiency is greater, causing the specimen to experience greater damage. Therefore, in the engineering practice of rock tunnel cut blasting, to utilize blasting energy effectively and enhance the effects of rock fragmentation, using the inverse-initiation method is recommended. In addition, in three-dimensional(3D) rock blasting, the bottom of the borehole has obvious end effects under the conditions of inverse initiation, and the crack distribution at the bottom of the borehole is trumpet-shaped. The occurrence of an end effect in the 3D linear-charge blasting model experiment is related to the initiation position and the blocking condition.

关键词： blasting linear charge initiation position computed tomography three-dimensional reconstruction damage