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Tuning microstructures of Mg-Ce-Ni hydrogen storage alloys via Cu and carbon nanotube additions

Nano Research 2024年第8期17卷 7203-7211页

作者： Linlin Zhang liang xiong Bingyang Gao Qingyun Shi Ying Wang Zhiya Han Zhenhua Zhang Chunli Wang Limin Wang Yong cheng State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Purification Equipment Research Institute of CSIC Handan 056002China

Mg-based alloys are regarded as highly promising materials for hydrogen *** significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics and high thermodynamic stability continue to limit their practical *** this study,to assess hydrogen storage alloys with enhanced properties,incorporating both internal microstructure modulation through the preparation of amorphous/nanocrystalline structures and surface property enhancement with the addition of Cu and carbon nanotubes(CNTs),the kinetic properties of activation and hydrogenation,thermodynamic properties,and dehydrogenation kinetics are *** results reveal a complementary interaction between the added Cu and CNTs,contributing to the superior hydrogen storage performance observed in sample 7A-2Cu-1CNTs with an amorphous/nanocrystalline structure compared to the other experimental ***,the samples are fully activated after the initial hydrogen absorption and desorption cycle,demonstrating outstanding hydrogenation kinetics under both high and low temperature experimental *** noteworthy is that the hydrogen absorption exceeds 1.8 wt.% within one hour at 333 ***,the activation energy for dehydrogenation is decreased to 64.71 kJ·mol^(–1).This research may offer novel insights for the design of new-type Mg-based hydrogen storage alloys,which possess milder conditions for hydrogen absorption and desorption.

关键词： Mg-Ni-Ce alloy hydrogen storage amorphous/nanocrystalline structure kinetics Cu and carbon nanotubes(CNTs)codoping

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Electromagnetic coupling reduction in dual-band microstrip antenna array using ultra-compact single-negative electric metamaterials for MIMO application

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Chinese Physics B 2017年第2期26卷 194-199页

作者： Xiao-Long Fu Guo-cheng Wu Wei-xiong Bai Guang-Ming Wang Jian-Gang liang Air and Missile Defense College Air Force Engineering University Xi＇ an 710051 China

In this paper, an ultra-compact single negative（SNG） electric waveguided metamaterial（WG-MTM） is first investigated and used to reduce the mutual coupling in E ＆ H planes of a dual-band microstrip antenna array. The proposed SNG electric WG-MTM unit cell is designed by etching two different symmetrical spiral lines on the ground, and has two stopbands operating at 1.86 GHz and 2.40 GHz. The circuit size is very compact, which is only λ_0/33.6 ×λ_0/15.1（where λ_0 is the wavelength at 1.86 GHz in free space）. Taking advantage of the dual-stopband property of the proposed SNG electric WG-MTM, a dual-band microstrip antenna array operating at 1.86 GHz and 2.40 GHz with very low mutual coupling is designed by embedding a cross shaped array of the proposed SNG electric WG-MTM. The measured and simulated results of the designed dual-band antenna array are in good agreement with each other, indicating that the mutual coupling of the fabricated dual-band antenna array realizes 9.8/11.1 d B reductions in the H plane, 8.5/7.9 d B reductions in the E plane at1.86 GHz and 2.40 GHz, respectively. Besides, the distance of the antenna elements in the array is only 0.35 λ_0（where λ_0 is the wavelength at 1.86 GHz in free space）. The proposed strategy is used for the first time to reduce the mutual coupling in E ＆ H planes of the dual-band microstrip antenna array by using ultra-compact SNG electric WG-MTM.

关键词： waveguided metamaterial(WG-MTM) dual-band microstrip antenna array mutual coupling reduction ultra-compact circuit size

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稀土元素Er、Yb和Y掺杂ZrO_(2)的第一性原理研究

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原子与分子物理学报 2025年第1期42卷 156-162页

作者：熊威任浩重庆交通大学航空学院重庆402247 重庆交通大学绿色航空技术研究院重庆401147

氧化锆具有声子能量低,介电常数高和带隙较宽等优良特性,并且立方相的氧化锆(cZrO_(2))透光率高,适合作为上转换发光材料的基质.采用基于密度泛函理论(DFT)的第一性原理平面波赝势法研究了稀土元素Er、Yb和Y掺杂cZrO_(2)的电子结构和光... 详细信息

氧化锆具有声子能量低,介电常数高和带隙较宽等优良特性,并且立方相的氧化锆(cZrO_(2))透光率高,适合作为上转换发光材料的基质.采用基于密度泛函理论(DFT)的第一性原理平面波赝势法研究了稀土元素Er、Yb和Y掺杂cZrO_(2)的电子结构和光学性质.计算结果显示,掺入Y元素后,cZrO_(2)转变为直接带隙材料,继续掺入Er和Yb原子后,费米能级移动到价带内,带隙显著减小.Y和Er混掺后,增强了cZrO_(2)在近红外波段的吸收能力.继续掺入Yb后,cZrO_(2)对近红外波段的吸收能力有了进一步地增加.

关键词：氧化锆第一性原理电子结构光学性质

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Metamaterial beam scanning leaky-wave antenna based on quarter mode substrate integrated waveguide structure

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Chinese Physics B 2017年第2期26卷 200-205页

作者： Guo-cheng Wu Guang-Ming Wang Xiao-Long Fu Jian-Gang liang Wei-xiong Bai Air and Missile Defense College Air Force Engineering University Xi＇an 710051 China

In this paper, we first propose a metamaterial structure by etching the same two interdigital fingers on the upper ground of quarter mode substrate integrated waveguide（QMSIW）. The simulated results show that the proposed QMSIWbased metamaterial has a continuous phase constant changing from negative to positive values within its passband. A periodic leaky-wave antenna（LWA）, which consists of 11 QMSIW-based metamaterial unit cells, is designed, fabricated,and measured. The measured results show that the fabricated antenna achieves a continuous beam scanning property from backward-43° to forward ＋32° over an operating frequencyrange of 8.9 GHz–11.8 GHz with return loss better than 10 d *** measured antenna gain keeps consistent with the variation of less than 2 d B over the operating frequency range with a maximum gain of 12 d B. Besides, the measured and simulated results are in good agreement with each other, indicating the significance and effectiveness of this method.

关键词： metamaterial leaky-wave antenna quarter mode substrate integrated waveguide(QMSIW) continuous beam scanning property

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Amino acids in piglet diarrhea:Effects,mechanisms and insights

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Animal Nutrition 2024年第1期16卷 267-274页

作者： Xihong Zhou Jing liang Xia xiong Yulong Yin Key Laboratory of Agro-ecological Processes in Subtropical Region Institute of Subtropical AgricultureThe Chinese Academy of SciencesChangsha 410125China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China

Piglet diarrhea is among one of the most serious health problems faced by the pig industry,resulting in significant economic *** disease in piglets has a multifactorial etiology that is affected by physiology,environment,and management *** is the most apparent symptom of intestinal *** a key class of essential nutrients in the piglet diet,amino acids confer a variety of beneficial effects on piglets in addition to being used as a substrate for protein synthesis,including maintaining appropriate intestinal integrity,permeability and epithelial renewal,and alleviating morphological damage and inflammatory and oxidative ***,provision of appropriate levels of amino acids could alleviate piglet *** amino acid effects are mediated by metabolites,gut microbes,and related signaling *** this review,we summarize the current understanding of dietary amino acid effects on gut health and diarrhea incidence in piglets,and reveal the mechanisms *** also provide ideas for using amino acid blends and emphasize the importance of amino acid balance in the diet to prevent diarrhea in piglets.

关键词： Piglet Amino acid Diarrhea Gut microbe Immune

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Joining of C_f/SiBCN composite with two Ni-based brazing fillers and interfacial reactions

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Journal of Materials Science & Technology 2017年第5期33卷 487-491页

作者： Wenwen Li Bo Chen Yi xiong Huaping xiong Yaoyong cheng Wenjiang Zou Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials School of Materials University of Manchester

G/SiBCN ceramic composite was joined using Ni-19Cr-10Si （BNi5） and Ni-33Cr-24Pd-3.5Si-0.5B filler alloys at 1170 ℃ for 10 min. Two kinds of Ni-based filler alloys exhibited good wettability on the CdSiBCN com- posite, with a contact angle of 13° and 4°, respectively, The microstructures of the brazed joints were investigated by electron-probe microanalysis （EPMA）, and three-point bend test was conducted for the joints at room temperature. When being brazed with BNi5 filler alloy, no evident reaction layer was ob- served at the surface of the joined composite, and the joint microstructure was characterized by Ni2Si matrix with scatteringly distributing mixture compounds of Cr23C6, Ni2Si and CrB. While Ni-Cr-Pd（Si,B） brazing alloy was used, a Cr23C6 reaction layer with a thickness of 11 μm was formed at the surface of the base composite. In the central part of the brazed joint, the phases were composed of Ni（Cr, Si） solid solution and complex compounds including Pd2Si, （Ni,Pd）2Si and Ni-B. The strength of Cf/SiBCN joint brazed with BNi5 filler alloy was 62.9 MPa at room temperature, whereas that with Ni-Cr-Pd（Si,B） filler alloy was at the same level.

关键词： Cf/SiBCN composite Brazing Microstructure Joint strength Interracial reaction

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Design of a NIM-based DAQ system

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Nuclear Science and Techniques 2017年第10期28卷 37-43页

作者： Wen-xiong Zhou Yan-Yu Wang liang-Ming Pan College of Power Engineering Chongqing UniversityChongqing 400044China Postdoctoral Station Chongqing UniversityChongqing 400044China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

In order to satisfy the requirements of beam measurement in the heavy ion medical machine and other small nuclear physics experiments, we designed and built a nuclear instrumentation module-based data acquisition system. This is composed of a set of functional modules and a purpose-built bus. One of the modules operates as a master, collecting data from the other slave modules. It then sends the data to the back-end computer via *** addition to the hardware, dedicated software has been designed and implemented. In this paper, we provide a detailed description of the architecture of the system, the data frame, and the software. The bus is the central part of the system. It can transmit data from the slave modules to the master at 33 MB/s. The frame used to transmit the data also ensures its integrity and monitors the hardware architecture. The client software is designed to process data in real time and store data on a hard disk for later analysis.

关键词：数据采集系统软件设计数据仓库功能模块专用软件硬件结构核物理实验医疗机械

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RECONSTRUCTION OF LAYER DATA WITH DEFORMABLE B-SPLINES

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 321-324页

作者： cheng Siyuan Zhang Xiangwei xiong Hanwei Faculty of Electromechanical Engineering Guangdong University of Technology Guangzhou 510090 China

A new B-spline surface reconstruction method from layer data based on deformable model is presented. An initial deformable surface, which is represented as a closed cylinder, is firstly given. The surface is subject to internal forces describing its implicit smoothness property and external forces attracting it toward the layer data points. And then finite element method is adopted to solve its energy minimization problem, which results a bicubic closed B-spline surface with C^2 continuity. The proposed method can provide a smoothness and accurate surface model directly from the layer data, without the need to fit cross-sectional curves and make them compatible. The feasibility of the proposed method is verified by the experimental results.

关键词： Revere engineering Surface reconstruction Deformable model Layer data

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Modeling the dynamics of a spruce forest and dwarf mistletoe population:a coupled system

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Journal of Forestry Research 2021年第4期32卷 1579-1585页

作者： Dianguang xiong Zhouyuan Li Yingmei liang chengming Tian College of Forestry Beijing Forestry UniversityBeijing 100083People’s Republic of China Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871People’s Republic of China Museum of Beijing Forestry University Beijing Forestry UniversityBeijing 100083People’s Republic of China

The parasitic plant dwarf mistletoe(Arceuthobium) is currently one of the most threatening infestations of coniferous forests worldwide,especially in Eurasia and North America,but its population dynamics in relation to one of its hosts(spruce) remain ***,toward understanding the population dynamics,differential equations were used to construct a life history model for the two populations,and two relatively independent subsystems,host and parasite,were generated from their symbiotic relationships.A suspected-infection model was used to couple *** resulting models were used to analyze structural changes in the *** each infected spruce was assumed to support 1000 parasite shoots,the spruce population first increased rapidly,then *** 2000 parasite shoots were assumed,the forest declined dramatically,slipping to zero in the 10 th year,and the spruce seedlings were unable to *** shoot population curves transformed from exponential J-shapes to logistic S-shapes,reaching population limitations as germination rates *** results provide important clues to understanding developmental trends of the present parasite population and will assist in reconstructing invasion histories.

关键词： Dwarf mistletoe Spruce Population dynamic model

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Low complexity reconfigurable architecture for the 5/3 and 9/7 discrete wavelet transform

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Journal of Systems Engineering and Electronics 2006年第2期17卷 303-308页

作者： xiong cheng yi Tian Jinwen Liu Jian Coll. of Electronic Information Engineering South Center Univ. for Nationalities Wuhan 430074 P.R. China Inst. of Pattern Recognition & Artificial Intelligence Key Lab. of Education Ministry for Image Processing and Intelligent Control Huazhong Univ. of Science & Technology Wuhan 430074 P.R. China

Efficient reconfigurable VLSI architecture for 1-D 5/3 and 9/7 wavelet transforms adopted in JPEG2000 proposal, based on lifting scheme is proposed. The embedded decimation technique based on fold and time multiplexing, as well as embedded boundary data extension technique, is adopted to optimize the design of the architecture. These reduce significantly the required numbers of the multipliers, adders and registers, as well as the amount of accessing external memory, and lead to decrease efficiently the hardware cost and power consumption of the design. The architecture is designed to generate an output per clock cycle, and the detailed component and the approximation of the input signal are available alternately. Experimental simulation and comparison results are presented, which demonstrate that the proposed architecture has lower hardware complexity, thus it is adapted for embedded applications. The presented architecture is simple, regular and scalable, and well suited for VLSI implementation.

关键词： VLSI discrete wavelet transform lifting scheme embedded decimation reeonfigurable.

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