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Up-conversion emissions of Er^(3+)-Yb^(3+) codoped Al_2O_3 nanoparticles by the arc discharge synthesis method

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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 1043-1046页

作者： DONG Bin1, CAO BaoSheng1, FENG ZhiQing1, WANG XingJun2, LI ChengRen3 & HUA RuiNian4 1 School of Science, Dalian Nationalities University, Dalian 116600, China 2 School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China 3 College of Physics and Electronic Technology, liaoning Normal University, Dalian 116029, China 4 College of Life Science, Dalian Nationalities University, Dalian 116600, China 1. School of Science Dalian Nationalities University Dalian 116600 China 2. School of Electronics Engineering and Computer Science Peking University Beijing 100871 China 3. College of Physics and Electronic Technology Liaoning Normal University Dalian 116029 China 4. College of Life Science Dalian Nationalities University Dalian 116600 China

The Er3+-Yb3+ codoped Al2O3 nanoparticles with an average particle size of about 50 nm have been synthesized by an arc discharge synthesis method. The green and red up-conversion emissions centered at about 526, 547 and 677 nm, corresponding respectively to the 2H11/2→4I15/2, 4S3/2→4I15/2 and 4 F9/2→4I15/2 transitions of Er3+, were detected by a 978-nm semiconductor laser diode excitation. The Annealing has evident effect on the up-conversion emissions of the samples: The red up-conversion emission is noticeable before annealing; however, the green up-conversion emission becomes predominant after annealing. The mixture of (Er,Yb)3Al5O12 and α-(Al,Er,Yb)2O3 phases is more favorable for green up-conversion emissions due to an enhancement of the ESA (I) of 4I11/2+a photon→4F7/2 and ET (III) of 2F5/2(Yb3+)+4I11/2(Er3+)→2F7/2(Yb3+)+4F7/2(Er3+) processes. The two-photon absorption up-conversion process is involved in the green and red up-conversion emissions. The results have proved that arc discharge synthesis is a new promising preparation technology for optical materials.

关键词： up-conversion Er3+-Yb3+ codoped Al2O3 arc discharge synthesis

Preparation and Properties of Paraffin/PMMA Shape-stabilized Phase Change Material for Building Thermal Energy Storage

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 231-239页

作者：孟多 ZHAO Kang WANG Anqi WANG Baomin School of Civil and Architectural Engineering Liaoning University of TechnologyJinzhou 121001China National Center for Materials Service Safety University of Science and Technology BeijingBeijing 10083China Institute of Building Materials Dalian University of TechnologyDalian 116024China

The composite phase change material(PCM) consisting of phase change paraffin(PCP) and polymethyl methacrylate(PMMA) was prepared as a novel type of shape-stabilized PCM for building energy conservation through the method of bulk polymerization. The chemical structure, morphology, phase change temperature and enthalpy, and mechanical properties of the composite PCM were studied to evaluate the encapsulation effect of PMMA on PCP and determine the optimal composition proportion. FTIR and SEM results revealed that PCP was physically immobilized in the PMMA so that its leakage from the composite was prevented. Based on the thermo-physical and mechanical properties investigations, the optimal mass fraction of PCP in the composite was determined as 70%. The phase change temperature of the composite was close to that of PCP, and its latent heat was equivalent to the calculated value according to the mass fraction of PCP in the composite. For estimating the usability in practical engineering, thermal stability, reliability and temperature regulation performance of the composite were also researched by TG analysis, thermal cycling treatments and heating-cooling test. The results indicated that PCP/PMMA composite PCM behaved good thermal stability depending on the PMMA protection and its latent heat degraded little after 500 thermal cycling. Temperature regulation performance of the composite before and after thermal cycling was both noticeable due to its latent heat absorption and release in the temperature variation processes. The PCP/PMMA phase change plate was fabricated and applied as thermal insulator in miniature concrete box to estimate its temperature regulation effect under the simulated environmental condition. It can be concluded that this kind of PCP/PMMA shape-stabilized PCM with the advantages of no leakage, suitable phase change temperature and enthalpy, good thermal stability and reliability, and effective temperature regulation performance have much potentia

关键词： shape-stabilized phase change material phase change paraffin polymethyl methacrylate temperature regulation building energy conservation

Aeroelastic Properties and Nonlinear Vibration Control of a Simply-Supported Lattice Sandwich Beam Embedded with Nitinol-Steel Wire Ropes

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Acta Mechanica Solida Sinica 2022年第5期35卷 755-764页

作者： Yewei Zhang Xichao Chen Donghui Li Jian Zang College of Aerospace Engineering Shenyang Aerospace UniversityShenyang110136China

As a novel vibration absorber,Nitinol-steel wire rope(NiTi-ST)has rarely been studied on vibration suppression for lattice sandwich beams in supersonic *** this paper,NiTi-ST with nonlinear stiffness and hysteretic damping is embedded in a lattice sandwich beam to control the beam's *** nonlinear restoring and hysteretic damping force of NiTi-ST are treated as *** dynamic equation is established based on Hamilton's *** amplitude responses of the beam with different NiTi-ST configurations are *** vibration-suppression effects and energy dissipation of lattice sandwich beam with different NiTi-ST configurations under different air velocities are also *** frequency-domain and time-domain methods are used to analyze the structural aeroelastic *** results show that the use of NiTi-ST can significantly suppress excessive vibration of a lattice sandwich beam in supersonic airflow.

关键词： Lattice sandwich beam Nonlinear vibration control Nitinol-steel wire rope Supersonic airflow

LHT model and Higgs boson production in association with a weak gauge boson at the LHC

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Chinese Physics C 2010年第10期34卷 1565-1569页

作者：刘伟岳崇兴苏雪松王永智 Department of Physics Liaoning Normal University

Considering the process pp→VH ＋X（V = W or Z） is a significant channel for searching for a light Higgs boson, we calculate the contributions of the littlest Higgs model with T-parity （called LHT model） to its production cross section. We find that, in most of the parameter space, the value of the relative correction parameter R is very small. However, with reasonable values of the free parameters, its value can be significantly larger.

关键词： LHT model light Higgs boson production cross section

Synthesis and Characterization of Polyaniline/MgTiO_(3) Composite with Excellent Thermal and Electrochemical Performance

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Journal of Wuhan University of Technology(Materials Science) 2021年第5期36卷 730-736页

作者： JIN Yazhou XING Weiwei ZHAO Siyu GU Xiaojie CHI Liping YUAN Meng XU Fen WANG Shaoxu College of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028China Dalian Eco-environmental Affairs Service Center Dalian 116028China Guangxi Key Laboratory of Information Materials(Guilin University of Electronic Technology) Guilin 541004China College of Environmental and Chemical Engineering Dalian Jiaotong UniversityDalian 116028China

This article explores the effects of doping ferroelectric materials MgTiO_(3) with different proportions on the properties of polyaniline(PANI).PANI/MgTiO_(3) composites were prepared by in-situ composite *** transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD)were used to characterize the structure of the *** electron microscope(SEM)was used to characterize the morphology of the *** thermal stability of the composites was investigated by thermogravimetry(TG)and derivative thermogravimetry(DTG).Electrochemical methods(cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS),and constant current charge-discharge test)were used to compare and analyze the electrochemical performance of the ***-DTG analysis and electrochemical experiments all show that the thermal stability and electrochemical properties of the PANI/MgTiO_(3) composite with a mass ratio of 82/18(w/w)are the *** results indicate that there is a synergistic effect between PANI and MgTiO_(3),which improves the performances of the PANI when the appropriate amount of MgTiO_(3) is added.

关键词： PANI/MgTiO_(3)composites in-situ composite method thermal stability electrochemical performance

Laser surface alloying fabricated porous coating on NiTi shape memory alloy

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中国有色金属学会会刊：英文版 2007年第2期17卷 228-231页

作者：张松张春华文效忠刘常升 School of Materials Science and Engineering Shenyang University of Technology Department of Industrial Systems Engineering Hon gkong Polytechnic University School of Materials and Metallurgy Northeastern University

Laser surface alloying technique was applied to fabricate a metallic porous coating on a solid NiTi shape memory alloy. By laser surface alloying a 40%TiH2-60%NiTi powder mixture on the surface of NiTi alloy using optimized laser process parameters, a porous but crack-free NiTi layer can be fabricated on the NiTi substrate. The porous coating is metallurgically bonded to the substrate NiTi alloy. The pores are uniformly distributed and are interconnected with each other in the coating. An average pore size of less than 10 μm is achieved. The Ni content of the porous layer is much less than that of the original NiTi surface. The existence of the porous coating on the NiTi alloy causes a 37% reduction of the tensile strength and 55% reduction of the strain as compared with the NiTi alloy. Possible biomedical or other applications for this porous surface with good mechanical strength provided by the substrate are prospective.

关键词：激光表面合金化制造多孔涂层 NiTi形状记忆合金

The littlest Higgs model with T-parity and some lepton flavor violation decay processes

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Science China(Physics,Mechanics & Astronomy) 2010年第11期53卷 1968-1974页

作者： YUE ChongXing,MA Wei,ZHANG TingTing,LIU Wei & LIU JinYan Department of Physics,liaoning Normal University,Dalian 116029,China 1. Department of Physics Liaoning Normal University Dalian 116029 China

The new particles predicted by the littlest Higgs model with T-parity (called LHT model) can induce the lepton flavor violation (LFV) couplings at the one-loop level,which can add contributions to some LFV *** into account the constraints of the experimental data on the relevant free parameters,we calculate the branching ratios of the LFV decay processes Z → l ˉl and τ-→μ-P 1 P 2 with P 1 P 2 = π + π-,K + K-,and K0 ˉK 0 in the context of this new physics *** find that the LHT model can indeed make significant contributions to some of these LFV decay *** Z factory option for the future high energy e + e-collider experiments will give severe constraints on the LHT model.

关键词： littlest Higgs model lepton flavor violation branching ratios

Break the strength-ductility trade-off in a transformation-induced plasticity high-entropy alloy reinforced with precipitation strengthening

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Journal of Materials Science & Technology 2022年第13期108卷 125-132页

作者： Dong Huang Yanxin Zhuang Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819China

Transformation-induced plasticity(TRIP)endows material with continuous work hardening ability,which is considered as a powerful weapon to break the strength-ductility ***,FCC based alloys with TRIP effect can not get rid of the“soft”feature of the structure entirely,resulting in insufficient yield ***,a Co_(x)Cr_(25)(AlFeNi)_(75-x) high-entropy alloy is *** phase is used as strengthening component to improve yield strength,while TRIP effect ensures *** with the previous TRIP high-entropy alloy,its yield strength is nearly doubled,and the uniform elongation is more than 55%at room ***,the corresponding multiphase microstructure evolution and deformation mechanisms are ***,stacking faults andΣ3 twin boundaries are confirmed to be the nucleation sites of HCP phase by *** composition design and proper heat treatment process make it a perfect combination of precipitation strengthening and transformationinduced plasticity,and thus guide design in the high-performance alloy.

关键词： High-entropy alloys Transformation-induced plasticity Precipitation strengthening Nucleation site HAADF-STEM

Heavy Charged Leptons from Type-III Seesaw and Pair Production of the Higgs Boson H at the International Linear e＋e- Collider

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Chinese Physics Letters 2010年第1期27卷 74-77页

作者：岳崇兴冯浩林马威 Department of Physics Liaoning Normal University Dalian 116029

Type-III seesaw scenario predicts the existence of the heavy charged leptons, which might generate observable signals in future collider experiments. We consider the contributions of these new particles to the process e＋e- →HH. We find that, for the large mixing between the light and heavy leptons, these new particles can indeed generate significant contributions to this process.

关键词： HEAVY leptons (Nuclear physics) HIGGS bosons LINEAR colliders PARTICLES (Nuclear physics) MIXING PHYSICS experiments