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International Journal of Minerals,Metallurgy and materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong Center of materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

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Metastable seed-crystals: epitaxial growth of branched-array organic heterostructure nanowires

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Science China Chemistry 2025年

作者： Jin Feng Zhen-Yu Geng Ting-Yao Song Ying-Xin Ma Chuan-Zeng Wang Wei Zhang Hong-Tao Lin Jin Zhou Shu-Ping Zhuo Shu-Hai Chen Xue-Dong Wang School of Chemistry and Chemical Engineering Shandong University of Technology institute of Functional Nano & Soft materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University College of Chemistry and Chemical Engineering Hunan Normal University

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (Eatt（023）=-104.25 kcal mol-1) of the exposed （023） crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7%between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

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Effect of LiF on the Optical Transmittance of Magnesium Aluminate Spinel

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Journal of Wuhan University of Technology(materials Science) 2012年第3期27卷 526-528页

作者：李法荟林红 Department of materials Science and Engineering Tsinghua University Research institute of Synthetic crystals

The effect of LiF as a sintering aid to the optical transparency of magnesium aluminate （MgAl2O4） spinel ceramics is studied. The spinel ceramics is prepared in a process proved to be suitable for commercial production. LiF, in different concentrations ranging from 0-2.5 wt%, is doped into MgAl2O4 powders prepared by sol-gel method. Sample MgAl2O4 ceramic discs are fabricated by ball milling, cold pressing, and hot-pressing, or hot-isostatic-pressing of the powder mixtures. Optical transparency measurements show that, hot-pressed samples exhibit higher transparency when more LiF is added. While for hot-isostatic pressed samples, excessive LiF content leads to a decrease in optical transparency. The optimal LiF doping quantity is suggested for the present technique.

关键词： transperent ceramics spinel liF sintering aid

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Preparation and Characteristic of Glass-Ceramics with Super Low Thermal Expansion Coefficient

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Journal of Rare Earths 2006年第z1期24卷 119-121页

作者： Zhao Chunxia Fan Shigang Chen Guangle Jiang Hui Wang Shengjun Wang Kun Research institute of Synthetic crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China

The preparation technics of glass-ceramics with super low coefficient of thermal expansion containing β-quartz solid solution as a main crystal phase based on the glass in the system Li2O-Al2O3-SiO2 was introduced. The composition of base glass, technics of melting and heat treatment effecting on characteristic of glass-ceramics was described. Specimens were prepared by melting, anneal and controlled two steps heat treatment. Crystal phase, microstructure and elementary distributing were studied by using XRD, SEM and EDS respectively. Prepared specimens show excellent transparency and super low thermal expansion coefficient of 2×10-8 ·K-1, which reaches international advanced level.

关键词： low thermal expansion Li2O-Al2O3-SiO2 transparent glass-ceramics

Low-agglomerated yttria nanopowders via decomposition of sulfate-doped precursor with transient morphology

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Journal of Rare Earths 2014年第4期32卷 320-325页

作者： R.P.Yavetskiy D.Yu.Kosyanov V.N.Baumer A.G.Doroshenko A.I.Fedorov N.A.Matveevskaya A.V.Tolmachev O.M.Vovk institute for Single crystals of NAS of Ukraine State Scientific Institution"institute for Single crystals"of NAS of Ukraine

The fabrication peculiarities of low-agglomerated yttria （Y2O3） nanopowders via thermal decomposition of sulfate-doped precursor with transient morphology were studied. It was determined that Y2（OH）5（NO3）x（CO2）y（SO4）z·nH2O （n=1-2） crystalline precursor underwent fragmentation and decomposition into isolated quasi-spherical Y2O3 particles upon calcination. Effect was con-nected with minimizing the free energy of the plate-like crystallites via reducing the contact surface until to the moment of spheroidi-zation and attainment of isolation that occurred atТ=1100 °С. Residual sulfate ions slowed down the surface diffusion during heat treatment thus retaining quasy-spherical morphology and low aggregation degree of Y2O3 nanopowders. Sulfate-doped yttria nanopowders with medium particle size of 53±13 nm possessed improved sinterability in comparison with undoped ones arising from finer particle size, narrower particle distribution and lower agglomeration degree.

关键词： precursor transient morphology sulfate-ions yttria nanopowders particle size sinterability rare earths

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Transparent Polycrystalline ZnS and ZnSe Growth by CVT Method

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Journal of Rare Earths 2006年第z1期24卷 72-74页

作者： Wang Xiangyang Qian Xun Zhang Xu Tian Hongchang Research institute of Synthetic crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China China University of Geosciences Beijing School of Earth Sciences and Resources Beijing 100083 China Research Institute of Synthetic Crystals Beijing 100018 China Research Institute of Synthetic Crystals Beijing 100018 China

ZnS and ZnSe are important infrared windows materials, which are grown by CVD method traditionally. Comparing with CVD method, the device of CVT (chemical vapor transport) method is much simpler. Transparent polycrystalline ZnS and ZnSe were grown by CVT method successfully. The grown ZnS and ZnSe shows that their transparencies exceed 40% in infrared region. After HIP treatment, the transmittance of as-grown CVT ZnS is improved greatly, which is better than 60%. The defects which effect transparency were studied.

关键词： ZnS ZnSe CVT

Post-tunable salt gel electrolytes toward flexible supercapacitor switches

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Journal of Energy Chemistry 2025年第1期 114-124页

作者： Hui Wang Shuang Chen Xuming Liu Qin Zhang Xin Liu Polymeric and Soft materials Laboratory School of Chemistry and Life Science and Advanced Institute of Materials Science Changchun University of Technology Polymeric and Soft materials Laboratory School of Chemical Engineering and Advanced Institute of Materials Science Changchun University of Technology

Convertible hydrogel supercapacitors have emerged as promising energy storage devices in switches,diodes, and transistors. However, inherent weaknesses in ionic conductivity, mechanical properties,and water retention of hydrogel electrolytes seriously hinder their development. Inspired by the hardness conversion of sea cucumber skin, a conductivity and mechanics dual-tunable salt gel electrolyte is successfully designed. The salt gel presents a reversible switching of conductors-insulators and a mechanical regulation between softness and hardness via the dissolution-crystallization transition of sodium acetate trihydrate（SAT）. Meanwhile, the salt gels spontaneously grow a layer of “armor” through saturated phase-change salt crystals effectively reducing water evaporation of hydrogel ***, this phase-change soft-rigid conversion strategy will expand the capabilities of gel-based flexible supercapacitors(area capacitance: 258.6 mF cm-2), and the capacitance retention rate could still reach 86.9% after 3000 cycles at high temperatures. Moreover, the salt gel supercapacitor is potentially used in over-heat alarm systems. It is anticipated that the strategy of conductivity and mechanics of dual-tunable salt gel would provide a new perspective on the development of energy storage devices,wearable electronics, and flexible robots.

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Studies and Properties of Ceramics with High Thermal Conductivity

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Journal of Rare Earths 2006年第z1期24卷 189-192页

作者： Chen Guangle Fan Shigang Zhao Chunxia Wang Kun Xia Shuqin Research institute of Synthetic crystals Research and Development Center Beijing 100018 China Research Institute of Synthetic Crystals Research and Development Center Beijing 100018 China Research Institute of Synthetic Crystals Research and Development Center Beijing 100018 China Research Institute of Synthetic Crystals Research and Development Center Beijing 100018 China Research Institute of Synthetic Crystals Research and Development Center Beijing 100018 China

The sintering technology of the AlN ceramics power were discussed. It is discussed that the compound sintering aids is consistent with the enhancement of the the thermal conductivity of AlN ceramics, and sintering technics is helped to the improvement of density. It is analyzed how to sinter machinable AlN ceramics with high thermal conductivity. And the microstructure of compound ceramics based on AlN was studied.

关键词： sintering aids hot-pressed high thermal conductivity machinable composite ceramics

Phonon engineering in Yb:La_(2)CaB_(10)O_(19)crystal for extended lasing beyond the fluorescence spectrum

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Light(Science & Applications) 2023年第9期12卷 1921-1929页

作者： Yanling Cheng Fei Liang Dazhi Lu Jingcheng Feng Guochun Zhang Haohai Yu Huaijin Zhang Yicheng Wu State Key Laboratory of Crystal materials and institute of Crystal materials Shandong UniversityJinan 250100China Key Lab Functional crystals and Laser Technology Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Since the first invention of the laser in 1960,direct lasing outside the fluorescence spectrum is deemed impossible owing to the“zero-gain”***,when electron-phonon coupling meets laser oscillation,an energy modulation by the quantized phonon can tailor the electronic transitions,thus directly creating some unprecedented lasers with extended wavelengths by phonon ***,we demonstrate a broadband lasing(1000-1280 nm)in a Yb-doped La_(2)CaB_(10)O_(19)(Yb:LCB)crystal,far beyond its spontaneous fluorescence *** calculations and in situ Raman verify that such a substantial laser emission is devoted to the multiphonon coupling to lattice vibrations of a dangling“quasi-free-oxygen”site,with the increasing phonon numbers step-by-step(n=1–6).This new structural motif provides more alternative candidates with strong-coupling laser ***,the quantitative relations between phonon density distribution and laser wavelength extension are *** results give rise to the search for on-demand lasers in the darkness and pave a reliable guideline to study those intriguing electron-phonon-photon coupled systems for integrated photonic applications.

关键词： beyond lasing spectrum

Photorefractive Self-Bending and High-Performance KNSBN:Cu Crystal Self-Pumped Phase-Conjugator

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Chinese Physics Letters 1992年第1期9卷 23-25页

作者： ZHANG Guangyin XU Jingjun WU Yuanqing LIU Simin SUN Daliang SONG Yongyuan CHEN Huanchu Department of Physics Nankai UniversityTianjin 300071 institute crystals materials Shandong UniversityJi'nan 250100

The mechanism for the high-performance KNSBN:Cu crystal self-pumped phase-conjugator is first put forward in this letter as no-loop photorefractive self-bending succesive four-wave mixing *** the photore fractive back... 详细信息

关键词： pumped Photorefractive Crystal