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China Foundry 2015年第4期12卷 269-276页

作者： Zhi Hu Yan Hong Yuan-sheng Rao Hong-xu Qiu xian-ming ruan Institute of Advanced Forming Nanchang University

The influence of Sm （Samarium） content on microstructure and mechanical properties of recycled die-cast YLl12 aluminum alloys was investigated. The results show that many small Sm-rich particles form in the recycled die-cast YLl12 alloys with Sm addition. At the same time, the secondary dendrite arm spacing in the YLl12 alloys modified with Sm is smaller than that of the unmodified alloy. The eutectic Si of recycled die- cast YL112-xSm alloys transforms from coarse acicular morphology to fine fibres. Mechanical properties of the investigated recycled die-cast YLl12 aluminum alloys are enhanced with Sm addition, and a maximal ultimate tensile strength value （276 MPa） and elongation （3.76%） are achieved at a Sm content of 0.6wt.%. Due to the modification of eutectic Si by Sm, numerous tearing ridges and tiny dimples on the fractures of tensile samples are observed.

关键词： rare earth aluminum alloy die casting samarium microstructure eutectic Si nano particles mechanical properties

Effects of neodymium addition on microstructure and mechanical properties of near-eutectic Al-12Si alloys

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Transactions of Nonferrous Metals Society of China 2015年第12期25卷 3877-3885页

作者：胡志阮先明闫洪南昌大学先进成形研究所南昌330031

The microstructure and mechanical properties of near-eutectic Al-12 Si alloys modified with 0-0.4% Nd（mass fraction） were investigated. The results indicate that a submicro- or nano-sized Al2 Nd phase is observed in the modified alloy with 0.3% Nd. The morphology of the α（Al） phase is significantly refined in the Nd-modified alloys. The primary Si morphology simultaneously changes into a fine, particle-like morphology, and the morphology of eutectic Si becomes fine-fibrous instead of coarse-acicular. Relatively few growth twins are observed on the surface of the Si plate in the Al-12Si-0.3Nd alloy at the optimal modification level. The mechanical property test results confirm that the mechanical properties of the as-cast Al-12 Si alloys are enhanced after the Nd addition, with optimal ultimate tensile strength（UTS） of 252 MPa and elongation（EL） of 13% at an Nd content of 0.3%. The improved mechanical properties are attributed to the refined morphology of Si phase and the formation of the Al2 Nd phase.

关键词： Al-12Si alloy neodymium refinement growth twins mechanical properties

GPIO-Based Continuous Sliding Mode Control for Networked Control Systems Under Communication Delays With Experiments on Servo Motors

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 99-113页

作者： Kamal Rsetam Zhenwei Cao Zhihong Man xian-ming Zhang the School of Software and Electrical Engineering Swinburne University of Technology the Department of Automated Manufacturing Al Khwarizmi College of Engineering University of Baghdad IEEE

To handle input and output time delays that commonly exist in many networked control systems(NCSs), a new robust continuous sliding mode control(CSMC) scheme is proposed for the output tracking in uncertain single input-single-output(SISO) networked control systems. This scheme consists of three consecutive steps. First, although the network-induced delay in those systems can be effectively handled by using Pade approximation(PA), the unmatched disturbance cames out as another difficulty in the control design. Second, to actively estimate this unmatched disturbance, a generalized proportional integral observer(GPIO) technique is utilized based on only one measured state. Third, by constructing a new sliding manifold with the aid of the estimated unmatched disturbance and states, a GPIO-based CSMC is synthesized, which is employed to cope with not only matched and unmatched disturbances, but also networkinduced delays. The stability of the entire closed-loop system under the proposed GPIO-based CSMC is detailedly *** promising tracking efficiency and feasibility of the proposed control methodology are verified through simulations and experiments on Quanser's servo module for motion control under various test conditions.

关键词：

A modified Kozeny-Carman equation for predicting saturated hydraulic conductivity of compacted bentonite in confined condition

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 984-993页

作者： Kunlin ruan xian-Lei Fu Department of Civil and Environmental Engineering Waseda UniversityTokyo169-8555Japan Jiangsu Key Laboratory of Urban Underground Engineering and Environmental Safety Institute of Geotechnical EngineeringSoutheast UniversityNanjing210096China

Kozeny-Carman(KC) equation is a well-known relation between hydraulic conductivity and pore properties in porous material. The applications of KC equation to predicting saturated hydraulic conductivities of sands and non-expansive soils are well documented. However, KC equation is incapable of predicting saturated hydraulic conductivity of expansive soil(e.g. bentonite) well. Based on a new dualpore system, this study modified KC equation for improving the prediction of saturated hydraulic conductivities of bentonites. In this study, an assumption that inter-layer space(micropore) has limited effect on fluid flow performance of compacted bentonite was adopted. The critical parameters including total porosity and total tortuosity in conventional KC equation were replaced by macroporosity and tortuosity of macropore, respectively. Macroporosity and microporosity were calculated by basal spacing of compacted bentonite, which was estimated by assuming that specific surface area is changeable during saturation process. A comprehensive comparison of bentonite’s saturated hydraulic conductivity predictions, including modified KC equation proposed in this study, conventional KC equation, and prediction method based on diffuse double layer(DDL) theory, was carried out. It was found that the predicted saturated hydraulic conductivity of bentonites calculated using modified KC equation fitted the experimental data better than others to a certain extent.

关键词： Kozenyecarman(KC)equation Saturated hydraulic conductivity Bentonite Pore size distribution(PSD) Specific surface area

有机金属卤化物钙钛矿CH_(3)NH_(3)PbBr_(3)的各向异性Rashba效应

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原子与分子物理学报 2025年第6期42卷 153-158页

作者：蔡锦鸿余达明周贤中广东工业大学集成电路学院广州510006

本研究通过密度泛函理论结合全相对论赝势对钙钛矿CH_(3)NH_(3)PbBr_(3)中的各向异性Rashba效应进行了深入研究.发现,Pb-Br八面体的畸变引起了导带最小间隙的三重态在自旋轨道耦合(SOC)效应和晶格形变下的分裂,导致在不同方向上呈现出... 详细信息

本研究通过密度泛函理论结合全相对论赝势对钙钛矿CH_(3)NH_(3)PbBr_(3)中的各向异性Rashba效应进行了深入研究.发现,Pb-Br八面体的畸变引起了导带最小间隙的三重态在自旋轨道耦合(SOC)效应和晶格形变下的分裂,导致在不同方向上呈现出强烈的各向异性.Rashba带分裂的最大系数可达2.0 eV?,并通过分析能级和电荷密度分布解释了Rashba效应的形成机制.这些研究结果有助于深化对CH_(3)NH_(3)PbBr_(3)性质的理解,同时为其在自旋电子学领域的潜在应用提供了理论基础.

关键词：钙钛矿 CH_3NH_3PbBr_3 密度泛函理论自旋轨道耦合

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A study on the dynamic spectral indices for SEP events on 2000 July 14 and 2005 January 20

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Research in Astronomy and Astrophysics 2020年第3期20卷 129-135页

作者： ming-xian Zhao Gui-ming Le Key Laboratory of Space Weather National Center for Space WeatherChina Meteorological Administration.Beijing 100081China

We have studied the dynamic proton spectra for the two solar energetic particle(SEP)events on2000 July 14(hereafter GLE59)and 2005 January 20(hereafter GLE69).The source locations of GLE59 and GLE69 are N22 W07 and N12 W58 *** fluxes>30 Me V have been used to compute the dynamic spectral indices of the two SEP *** results show that spectral indices of the two SEP events increased more swiftly at early times,suggesting that the proton fluxes>30 Me V might be accelerated particularly by the concurrent flares at early times for the two SEP *** the GLE69 with source location at N12 W58,both flare site and shock nose are well connected with the Earth at the earliest ***,only the particles accelerated by the shock driven by eastern flank of the CME can propagate along the interplanetary magnetic field line to the Earth after the *** the GLE59 with source location at N22 W07,only the particles accelerated by the shock driven by western flank of the associated CME can reach the Earth after the *** results also show that there was slightly more than one hour during which the proton spectra for GLE69 are softer than that for GLE59 after the flares,suggesting that the shock driven by eastern flank of the CME associated with GLE69 is weaker than the shock driven by the western flank of the CME associated with *** results support that quasi-perpendicular shock has stronger potential in accelerating particles than the quasi-parallel *** results also suggest that only a small part of the shock driven by western flank of the CME associated with the GLE59 is quasi-perpendicular.

关键词： Sun:flares-Sun coronal mass ejections(CMEs)-Sun particle emission-Sun solarterrestrial relations

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自激式电感耦合等离子体光源设计及光谱分析

光谱学与光谱分析 2025年第1期45卷 66-71页

作者：卢思贤龙开红詹陈锐李明北方工业大学电气与控制工程学院北京100144 益阳职业技术学院电子与信息工程学院湖南益阳413055

电感耦合等离子体(ICP)光谱仪是一种应用范围很广的元素分析仪,主要用于元素定性与定量的分析。ICP光源是光谱仪的核心部件,它在光谱仪中扮演着至关重要的角色。目前主流的ICP光源有两种:自激式和他激式,各自具有优缺点。他激式光源电... 详细信息

电感耦合等离子体(ICP)光谱仪是一种应用范围很广的元素分析仪,主要用于元素定性与定量的分析。ICP光源是光谱仪的核心部件,它在光谱仪中扮演着至关重要的角色。目前主流的ICP光源有两种:自激式和他激式,各自具有优缺点。他激式光源电路复杂、体积庞大、阻抗匹配速度较慢、最大输出功率有限。设计了一种基于镀金工艺的高功率MOSFET和变频实现阻抗匹配的自激式ICP光源,该光源采用射频放大和阻抗匹配一体化的设计,把从负载线圈采样的频率信号f_(1)以及功率放大电路放大后的频率相位f_(0)进行相位比较,再根据两者相位差的变化,进而控制频率的变化,实现阻抗匹配;设计上采用了镀金工艺的金属化硅N通道型高功率的MOSFET实现功率放大,具有更大的功率密度、更小的体积,最大输出功率超过2400 W。对研制的ICP光源进行了电学静态测试,给出了鉴相器、压控振荡器以及功率的输出特性,验证了各电路在相应工作状态下的性能表现;同时结合光谱仪进行了包含Ba、Na和Li元素标准溶液的测试,获得了目标元素的光谱信号;另外,对获得的光谱信号进行了处理,使用了基于EEMD特征增强的方法对目标元素光谱信号进行有效增强,信号的线性决定系数(R^(2))从0.97降至0.99,相对标准偏差(RSD)从6.47%降至1.07%,增强了信号的准确性和可用性。本文所研制的自激式ICP光源,通过射频放大和阻抗匹配一体化设计缩小了体积,变频技术使阻抗匹配速度从毫秒级提升到纳秒级,镀金工艺的MOSFET技术使最大输出功率从原来的1800 W增加到2400 W,为ICP光源的进一步优化和应用奠定了基础,具有重要的科学研究和工程实践意义。

关键词：自激式ICP光源阻抗匹配光谱信号 EEMD算法

Recent advances and perspectives of metal/covalent-organic frameworks in metal-air batteries

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Journal of Energy Chemistry 2021年第12期30卷 113-129,I0003页

作者： ming Zhong ming Liu Na Li xian-He Bu School of Materials Science and Engineering Tianjin Key Laboratory of Metal and Molecule-Based Material ChemistryNankai UniversityTianjin 300350China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou 730050GansuChina College of Chemistry Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)Nankai UniversityTianjin 300071China

Metal-air batteries(MABs)have attracted considerable attention as a novel energy technology that can alleviate the severe energy crisis and environmental *** primary processes,including oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)occur on the air cathode and dominate the battery performance during battery charging and ***,metal-organic frameworks(MOFs)and covalent-organic frameworks(COFs)emerge as promising cathode catalysts due to their structure and composition *** unique characteristics of MOFs and COFs contribute to improved *** review mainly summarizes the recent applications of MOFs and COFs in a series of MABs,mainly including lithium-and zinc-air ***,some critical issues are emphasized regarding MOFs and COFs used in other MABs limited progress,their fabrication and alternatives to potential problems.

关键词： Metal-organic frameworks Covalent-organic frameworks Li-air batteries Zn-air batteries Active sites

Effect of temperature on the hydration process and strength development in blends of Portland cement and activated coal gangue or fly ash

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第2期12卷 162-170页

作者： Pei-ming WANG xian-ping LIU Key Laboratory of Advanced Civil Engineering Materials (Tongji University) Ministry of Education Shanghai 201804 China

This paper describes the results of an investigation into the effect of the variation of curing temperatures between 0 and 60 °C on the hydration process,pore structure variation,and compressive strength development of activated coal gangue-cement blend(ACGC) . Hardened ACGC pastes cured for hydration periods from 1 to 360 d were examined using the non-evaporable water method,thermal analysis,mercury intrusion porosimetry,and mechanical testing. To evaluate the specific effect of activated coal gangue(ACG) as a supplementary cementing material(SCM) ,a fly ash-cement blend(FAC) was used as a control. Results show that raising the curing temperature accelerates pozzolanic reactions involving the SCMs,increasing the degree of hydration of the cement blends,and hence increasing the rate of improvement in strength. The effect of curing temperature on FAC is greater than that on ACGC. The pore structure of the hardened cement paste is improved by increasing the curing temperature up to 40 °C,but when the curing temperature reaches 60 °C,the changing nature of the pore structure leads to a decrease in strength. The correlation between compressive strength and the degree of hydration and porosity is linear in nature.

关键词： Activated coal gangue (ACG) Fly ash (FA) Blended cement Hydration Curing temperature Strength

Research on the influence of quadrupole deformation and continuum effects on the exotic properties of 15,17,19B with the complex momentum representation method

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Nuclear Science and Techniques 2023年第2期34卷 98-108页

作者： Xue‑Neng Cao xian‑xian Zhou ming Fu Xin‑Xing Shi School of Management Science and Engineering Anhui University of Finance and EconomicsBengbu 233030China School of Mechanics and Optoelectronic Physics Anhui University of Science and TechnologyHuainan 232001China

The properties of exotic nuclei are the focus of the present ***-neutron halo structures of neutron-rich17,19B were experimentally *** studied the formation mechanism of halo phenomena in17,19B using the complex momentum representation method applied to deformation and continuum *** examining the evolution of the weakly bound and resonant levels near the Fermi surface,s–d orbital reversals and certain prolate deformations were *** addition,by analyzing the evolution of the occupation probabilities and density distributions occupied by valence neutrons,we found that the ground state of15B did not exhibit a halo and the ground states of17B and19B exhibited halos at 0.6≤β2≤0.7 and0.3≤β2≤0.7,*** low-l components in the valence levels that are weakly bound or embedded in the continuous spectrum lead to halo formation.

关键词： Quadrupole deformation Resonant states Complex momentum representation Halo