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Growth, morphology and anisotropic thermal properties of Nd-doped Sr3La2(BO3)4 crystal

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Growth, morphology and anisotropic thermal properties of Nd-...

Growth,morphology and anisotropic thermal properties of Nd-doped Ca3La2(BO3)4 crystal

中国晶体学会第五届全国会员代表大会暨学术大会（晶体生长分会场）

作者： Zhong-Ben Pan huai-jin zhang Ji-Yang Wang State Key Laboratory of Crystal Materials and Institute of Crystal Materials Shandong University

A high-quality Nd3+:Sr3La2(BO3)4 laser crystal was grown by the Czochralski *** phase purity was characterized X-ray powder diffraction.A series of possible growth faces(hkl)of the external morphology were deduced and compared with the as-grown crystal boules according to the Bravais-Friedel Donnay-Harker(BFDH)*** set of thermal properties,including the thermal expansion,thermal diffusivity,specific heat,and

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Growth,morphology and anisotropic thermal properties of Nd-d...

Bending Stiffness of Concrete-Filled Steel Tube and Its Influence on Concrete Placement Timing of Composite Beam-String Structure

第十六届全国晶体生长与材料学术会议

作者： Zhong-Ben Pan huai-jin zhang Ji-Yang Wang State Key Laboratory of Crystal Materials and Institute of Crystal Materials Shandong University

A high-quality Nd3+:Ca3La2(BO3)4 laser crystal was grown by the Czochralski *** phase purity was characterized X-ray powder diffraction.A series of possible growth faces(hkl) of the external morphology were deduced and compared with the as-grown crystal boules according to the Bravais-Friedel Donnay-Harker(BFDH) *** set of thermal properties,including the

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Structural Durability & Health Monitoring 2025年第1期19卷 55-75页

作者： Zhenyu zhang Quan jin Haitao zhang Zhao Liu Yuyang Wu Longfei zhang Renzhang Yan CCCC Third Highway Engineering Co. Ltd.Beijing101300China School of Civil Engineering Chongqing Jiaotong UniversityChongqing400074China

When the upper chord beam of the beam-string structure(BSS)is made of concrete-filled steel tube(CFST),its overall stiffness will change greatly with the construction of concrete placement,which will have an impact on the design of the tensioning plans and selection of control measures for the *** order to accurately obtain the bending stiffness of CFST beam and clarify its impact on the mechanical properties of composite BSS during construction,the influence of some factors such as height-width ratio,wall thickness of steel tube,elasticity modulus of concrete,and friction coefficient on the bending stiffness are analyzed parametrically by the numerical simulation technology based on an actual *** calculation formula of the equivalent bending stiffness of CFST is also established through mathematical statistical ***,the equivalent bending stiffness is introduced into the construction and use stages of the composite BSS,respectively,and the mechanical properties such as prestress-tensioning control value,structural deformation,and internal force of key members are comparatively analyzed when adopting two different construction ***,the optimal construction plan of concrete placement first and then prestress-tensioning is proposed.

关键词： Concrete panels freeze-thaw damage compression-shear crack tension-shear crack

Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 246-257页

作者： zhang Jian NIE Wei HUANG jin ZHU Ke LIU Ruxia zhang Ruizhi LUO Guoqiang SHEN Qiang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys

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Broadband and perfect terahertz absorber based on multilayer metamaterial with cross-ring patterned structures

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Optoelectronics Letters 2025年第1期21卷 1-6页

作者： WEN jin LIU Zhanzhi WU Zhengwei PAN Yu zhang Ying School of Science Xi'an Shiyou University Shaanxi Key Laboratory of Measurement and Control Technology for Oil and Gas Wells

Broadband and perfect terahertz absorber based on multilayer metamaterial using cross-ring patterned structures is proposed and investigated. The structure of the absorber is double absorption layers consisting of a chromium cross ring and eight isosceles right triangles. The unique structure of the double absorbing layers excites the electric dipole multimode resonance, giving rise to high absorption performance. Meanwhile, the influence of construal parameters on absorber behavior is also discussed. The numerical results show that the absorption achieves over 90% ranging from 2.45 THz to 6.25 THz and 99% absorption in the range of 3.7—5.3 THz. The realization of broadband and perfect absorber is described using the impedance matching principle. It is obviously found that the absorber is insensitive to the high angle of incidence for both transverse electric(TE) and transverse magnetic(TM) polarizations. Compared with the former reports, this absorber has remarkable improved absorption efficiency and smaller period. The terahertz absorber may be found applications in the fields of energy capture and thermal detection.

关键词： Metamaterials

Potassium ions and cyano group modified g-C3N4 for effective generation of H2O2 through two-electron oxygen reduction

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Science China Chemistry 2025年第1期68卷 192-200页

作者： Dongying Wang Shulan Pu Yongmin Chen Ke Lei Yujie Duan Linjiao Mao Xuhui Zeng Xi Luo Yuntao zhang Yuqin Dong jin Zhong zhang Yan Sun School of Mechanical Engineering Chengdu University Department of Chemistry and Biochemistry University of California

Potassium ions （K+） doped graphitic carbon nitride （g-C3N4） was prepared by a thermal etching method using potassium hydroxide （KOH） as an ion *** transform infrared spectroscopy （FTIR） and X-ray photoelectron spectroscopy （XPS）results showed that the generation of the cyano group was detected while introducing K+.Under simulated sunlight irradiation,the sample with a K+doping amount of 10%showed the highest hydrogen peroxide （H2O2） generation rate of2,140.2μmol *** apparent quantum yield （AQY） at 400 nm and the solar-to-chemical conversion （SCC） are 4.35%and1.23%,respectively.K+acted as a bridge between g-C3N4layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons （H+） and promoted the yield of *** catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals （·O2-）were the most important active species in the reaction *** production of H2O2was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving H2O2generation.

关键词： photocatalysis hydrogen peroxide oxygen reduction reaction potassium doping cyano group

Effect of pouring time on microstructure and mechanical properties of centrifugal cast Ti-46Al alloy tubes

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China Foundry 2025年

作者： Gang Huang Qian Dang Cong-cong Su jing Zhao Chi zhang Guo-huai Liu Zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern University School of Materials Science and Engineering Shenyang University of Technology

The grain size of TiAl alloy castings prepared by traditional casting process is coarse, thus showing poor mechanical properties. In this study, a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was introduced. This research comprehensively examined the influence of pouring time on the microstructure and mechanical performance of the castings, employing both experimental approaches and ProCast simulation methodologies. The findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed grains. Under the condition of pouring temperature of 1,600 °C, rotation speed of 800 r·min-1and pouring time of 6 s, the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa, and the tensile strength at 800 °C reaches 705 MPa, which is significantly higher than that of traditional as-cast Ti-Al alloy.

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Separation of the ionospheric and thermospheric contributions in the data from the Triple Ionosophere Photo Meter onboard the Feng-Yun 3E satellite

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Science China Earth Sciences 2025年第1期68卷 172-184页

作者： Fang JIANG Tian MAO jin-Song WANG Xiu-Qing HU Xiao-Xin zhang Liping FU Nan JIA Tianfang WANG National Space Science Center Chinese Academy of Sciences Beijing Key Laboratory of Space Environment Exploration Key Laboratory of Environmental Space Situation Awareness Technology National Satellite Meteorological Center China Meteorological Administration

The Triple Ionosphere Photo Meter （TRIPM） is a far ultraviolet nadir-view photometer that is onboard the secondgeneration,polar-orbiting Chinese meteorological satellite Feng-Yun 3E （FY-3E）,which was launched on July 5,*** has three channels,and each is used to measure different types of emissions:（1） 135.6 nm airglow produced by the recombination of the O+ions and electrons in the absence of sunlight （nighttime channel）;（2） 135.6 nm airglow from the OI when sunlight is present （daytime/dusk-dawn 135.6 nm channel）;and （3） Airglow in the N2LBH of the TRIPM （daytime/dusk-dawn N2LBH channel）.FY-3E is a satellite operating in the early morning ***,the data are mostly distributed on the dawndusk side or at times when the solar zenith angle is relatively *** this study,combined with simulation calculations,the data are *** further explore the application value of the data products,a model is used to separate the ionospheric radiative recombination contribution from the thermosphere photoelectron impact excitation contribution in the data from the daytime/dusk-dawn 135.6 nm *** approach not only improves the accuracy of O/N2derived from the 135.6 nm channel and N2LBH channel but also provides the ionospheric 135.6 nm radiance at the same time as the *** results show that the 135.6 nm radiance originating from the combination of O+and electrons extracted from the measurement data exhibits similar equatorial anomaly peak structure characteristics and seasonal variations as the corresponding GPS total electron content （TEC） *** the other hand,the separated 135.6 nm radiance generated from the thermosphere photoelectron collision excitation does not contain radiative recombination contributions;thus,the ionosphere influence is greatly avoided when the O/N2is obtained.

关键词： Far ultraviolet 135.6 nm emission intensity Photoelectron impact excitation Radiative recombination excitation

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An Efficient Boron Source Activation Strategy for the Low‑Temperature Synthesis of Boron Nitride Nanotubes

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Nano-Micro Letters 2025年第1期17卷 548-558页

作者： Ying Wang Kai zhang Liping Ding Liyun Wu Songfeng E Qian He Nanyang Wang Hui Zuo Zhengyang Zhou Feng Ding Yue Hu jin zhang Yagang Yao National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional Materialsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093People’s Republic of China School of Electronic Information and Artificial Intelligence Shaanxi University of Science&TechnologyXian 710000People’s Republic of China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science&TechnologyXian 710000People’s Republic of China Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325000People’s Republic of China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518000People’s Republic of China College of Chemical and Molecular Engineering Peking UniversityBeijing 100871People’s Republic of China

Lowering the synthesis temperature of boron nitride nanotubes(BNNTs)is crucial for their *** primary reason for adopting a high temperature is to enable the effective activation of highmelting-point solid *** this study,we developed a novel approach for efficiently activating boron by introducing alkali metal compounds into the conventional MgO–B *** approach can be adopted to form various low-melting-point AM–Mg–B–O growth *** growth systems have improved catalytic capability and reactivity even under low-temperature conditions,facilitating the synthesis of BNNTs at temperatures as low as 850℃.In addition,molecular dynamics simulations based on density functional theory theoretically demonstrate that the systems maintain a liquid state at low temperatures and interact with N atoms to form BN *** findings offer novel insights into the design of boron activation and are expected to facilitate research on the low-temperature synthesis of BNNTs.

关键词： Boron nitride nanotubes Low-temperature Boron activation Density functional theory

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