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Influence of(Mg_(1/3)Nb_(2/3))complex substitutions on crystal structures and microwave dielectric properties of Li2TiO3 ceramics with extreme low loss

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Journal of Materiomics 2018年第4期4卷 368-382页

作者： Huan-Huan Guo Di Zhou Li-Xia Pang jin-zhan su Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchSchool of Electronic and Information EngineeringXi'an Jiaotong UniversityXi'an710049China Micro-optoelectronic Systems Laboratories Xi'an Technological UniversityXi'an710032ShaanxiChina International Research Centre for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'anShaanxi710049China

A systematic investigation of the Li2Ti1-x(Mg_(1/3)Nb_(2/3))xO_(3)(0.1≤x≤0.35)solid solutions synthesized by traditional solid-state reaction method is reported in this *** the composition range of 0.1≤x≤0.25,a monoclinic rock salt structured solid solution was *** x increased to 0.3,a phase transition from monoclinic to cubic phase,along with an order-disorder phase transition,was *** x increased from 0.1 to 0.35,the microwave permittivity(εr)and temperature coefficient of resonant frequency(TCF)of the Li2Ti1-x(Mg_(1/3)Nb_(2/3))xO_(3)ceramics decreased linearly from 21.0 to 18.6,+27.1 to-19.4 ppm/℃,*** Li_(2)Ti_(0.75)(Mg_(1/3)Nb_(2/3))0.25O_(3)ceramic sintered at 1170℃shows high performance of microwave dielectric properties with aεr~19.6,a Qf(Q=quality factor=1/dielectric loss;f=resonant frequency)~109,770 GHz(at 7.7 GHz)and a near zero TCF~t 1.2 ppm/℃.Moreover,the burying sintering process can reduce the volatilization of lithium so that the porosity of Li_(2)Ti_(0.75)(Mg_(1/3)Nb_(2/3))0.25O_(3)ceramic was reduced effectively,which made Li_(2)Ti_(0.75)(Mg_(1/3)Nb_(2/3))0.25O_(3)ceramic promising for future *** area electron diffraction patterns,high-resolution transmission electron microscopy,Raman and far-infrared spectra were employed to study the relation between crystal structure and microwave dielectric properties in detail.

关键词： Microwave dielectric properties Phase evolution Crystal structure High quality

Insight into the particle shape on the impact of dry granular flow against a rigid barrier: A DEM study

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Journal of Earth Science 2025年

作者： Rui-Xiao zhan Dong su Xiang-Sheng Chen Yuan-Jun Jiang Guo-Ping Lei jing-jing Yu Key Laboratory for Resilient Infrastructures of Coastal Cities (MOE)， Shenzhen University College of Civil and Transportation Engineering， Shenzhen University School of Architecture and Urban Planning， Shenzhen University Shenzhen Key Laboratory of Green， Efficient and Intelligent Construction of Underground Metro Station， Shenzhen University Institute of Mountain Hazards and Environment， Chinese Academy of Sciences School of Transportation， Civil Engineering & Architecture， Foshan University

The effect of particle shape on the impact of dry granular flow remains an open area for further investigation. Five distinct particle shapes were examined in this study using discrete element simulations after calibrating the numerical model using a published work. The findings indicated that the particle shape had a significant influence on granular mobility. With negligible variations in normalized kinetic energy between particles of different shapes， the effect of particle shape on the increasing rate of kinetic energy became more obvious. All irregular particle scenarios had longer accumulated particle lengths down the channel than spherical particles. Variations in particle shape led to adjustments in the distribution of impact forces on the barrier. These findings substantially enhance our understanding of the distinctive effects of particle shapes on the impact mechanism of dry granular flow.

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Boosting aqueous nickel-zinc battery stability with bimetallic ion-integrated 1D metal-organic nanowires

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Science China Chemistry 2025年

作者： Yihao Chen jin Liang Yichun su Guoyin Zhu Hengyue Xu Hongye Ding Guangxun zhang Dianheng Yu Zizhou Shen Yizhou zhang Wei Huang Huan Pang School of Chemistry and Chemical Engineering Yangzhou University Key Laboratory of Flexible Electronics (KLoFE) & Institute of Advanced Materials (IAM) School of Flexible Electronics (Future Technologies) Nanjing Tech University (NanjingTech) Institute of Advanced Materials and Flexible Electronics (IAMFE) School of Chemistry and Materials Science Nanjing University of Information Science & Technology Department of Chemistry Tsinghua University State Key Laboratory of Coordination Chemistry Nanjing University

Limited by low conductivity,designing cathode materials with excellent electron transfer efficiency for high-performance nickel-zinc batteries （NZBs） remains *** this study,a series of bimetallic metal-organic nanowires were fabricated by doping M ions in NiNTA,resulting in NiMNTA (M=Mg2+,Mn2+,Co2+,Zn2+,Ag+),and NixCo6-xNTA （x=1,2,3,4,5）.The proportions and types of metal ions can be modified without altering the initial coordination structure.X-ray absorption fine structure spectroscopy （XAFS） revealed that only M–O bonds,not metal bonds,were present in the *** performance of Ni2Co4NTA as the cathode for aqueous NZBs was significantly improved,achieving the maximum energy density of 279.17Wh kg-1with the high cycle stability （retention rate of 72.0%after 1,000 cycles）.The flexible Ni2Co4NTA//Zn@carbon cloth battery employing gel electrolyte also exhibits the excellent Coulombic efficiency of 96%after 350 *** approach shows considerable potential for designing one-dimensional materials with bimetallic modifications,providing new strategies for developing cathode materials for NZBs with high specific capacity and cycle stability.

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一例马肠梗阻的诊治

草食家畜 2017年第2期 52-54页

作者：王栋张毅丁浩况玲买占海张瑾瑜苏战强新疆农业大学动物医学学院新疆乌鲁木齐830052

为了提高临床上马肠梗阻的确诊率和治愈率,以出现急起急卧、后肢踢腹、打滚的临床症状结合直肠检查触诊到明显的阻塞物来进行诊断,通过通肠、镇痛、解毒的治疗原则,使用中药方剂"痉挛疝散"胃管投服,并配合西医用药以及外科的直肠破结的... 详细信息

为了提高临床上马肠梗阻的确诊率和治愈率,以出现急起急卧、后肢踢腹、打滚的临床症状结合直肠检查触诊到明显的阻塞物来进行诊断,通过通肠、镇痛、解毒的治疗原则,使用中药方剂"痉挛疝散"胃管投服,并配合西医用药以及外科的直肠破结的方法进行治疗,结果经2天治疗,成功治愈本病。说明中西医结合是治疗马肠梗阻的一种有效方法,为马肠梗阻的诊断与治疗提供了有益的参考。

关键词：马肠梗阻通肠镇痛

NUMERICAL ANALYSIS OF SATURATED-UNSATURATED SEEPAGE FLOW IN FRACTURED ROCK MASS DUE TO suRFACE INFILTRATION

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Journal of Hydrodynamics 2001年第4期13卷 28-33页

作者： Hu, Yun-jin su, Bao-Yu zhan, Mei-Li Dept. of Hydraulic Eng. Tsinghua Univ. Beijing 100084 China

Seepage flow in fractured rock mass due to surface infiltration is a saturated-unsaturated seepage process. Aimed at rock mass with large fracture density, which can be equivalent to continuum, a mathematical model for saturated-unsaturated seepage flow in fractured rock mass due to surface infiltration was established in this paper. The Galerkin finite element method was used in numerical simulation and a finite element program used to calculate saturated-unsaturated seepage flow due to surface infiltration was worked out. A model experiment was used to examine the reasonableness of the program. The results show that the proposed model and program are reasonable. The application of the analysis method in an engineering project shows that the method is reliable and feasible.

关键词： Computer simulation Mathematical models Seepage

计算机视觉技术赋能大学英语课堂展示中的学习投入研究

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新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 144-151页

作者：谭苏燕王晋军广州大学外国语学院广东广州510010

学习投入是预测学习者学习效果的重要指标,学术界对其与课堂展示间的相关性研究鲜有涉猎。文本以某综合性大学303名非英语专业本科生为研究对象,采用人工智能与计算机视觉技术模型YOLOv7对大学英语课堂中的课堂展示实录进行学习投入多... 详细信息

学习投入是预测学习者学习效果的重要指标,学术界对其与课堂展示间的相关性研究鲜有涉猎。文本以某综合性大学303名非英语专业本科生为研究对象,采用人工智能与计算机视觉技术模型YOLOv7对大学英语课堂中的课堂展示实录进行学习投入多模态数据分析,并辅以问卷调查,形成双向印证。研究发现,学生课堂展示中的行为投入、认知投入和情感投入值均等于或高于3.78,投入结果均值达4.01,说明学生在课堂展示中的学习投入情况良好。此外,不同时段课堂展示对学生行为投入的影响显著,学生专注度及参与度在课堂前10分钟的课堂展示中效果最佳。文本为课堂展示的有效性提供了智能化、多模态、多维度的实证支持,为课堂教学的数智技术应用提供了新视角。

关键词：大学英语课堂展示学习投入计算机视觉技术展示时段

Multi-Objective Optimization Analysis of Auxiliary Flux Modulator Magnetic Gear with Unequal Magnetic Poles

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CES Transactions on Electrical Machines and Systems 2023年第4期7卷 372-378页

作者： zhan su Libing jing the College of Electrical Engineering and New Energy Hubei Provincial Engineering Technology Research Center for MicrogridChina Three Gorges UniversityYichang 443002China

To enhance the output torque and minimize the torque ripple of coaxial magnetic gear(CMG),a novel auxiliary flux modulator CMG with unequal magnetic poles is *** design incorporates an inner rotor with an asymmetric sector and a trapezoidal combined N-S pole structure,featuring Halbach arrays for the arrangement of permanent magnets(PMs).The outer rotor PMs adopt a Spoke-type *** optimize the CMG for high output torque and low torque ripple,a sensitivity analysis is conducted to identify key size parameters that significantly influence the optimization *** on the sensitivity hierarchy of these parameters,a multi-objective optimization analysis is performed using a genetic algorithm(GA)to determine the optimal structural parameter values of the *** addition,a coaxial magnetic gear(CMG)topology with 4 inner and 17 outer pole pairs is adopted,and the parametric model is ***,the electromagnetic properties of the CMG are evaluated using the finite element *** results indicate a remarkable reduction in torque ripple,specifically by 46.15%.

关键词： Auxiliary flux modulator CMG Torque Multi-objective optimization Parameter sensitivity

Early-Middle Ordovician brachiopod dispersal patterns in South China

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Integrative Zoology 2014年第2期9卷 121-140页

作者： Renbin zhan Jisuo jin State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjingChina Department of Earth Sciences Western UniversityLondonOntarioCanada

Paleobiogeographic patterns of the brachiopod faunas before and during the first radiation of the Great Ordovi-cian Biodiversification Event(GOBE)in South China at 6 different localities from the upper Jiangnan Slope to the vast area of the Upper Yangtze Platform show several interesting ***,the initial brachiopod diver-sity acme was accompanied by both high origination and extinction ***,no significant changes took place in the taxonomic composition and paleobiogeographic pattern of the brachiopod fauna during the radia-tion at 5 of the 6 localities studied except the near shore locality,where the first brachiopod radiation was much later than at other localities and was marked by a dramatic increase in endemic ***,orthides were the predominant brachiopod group during the radiation,and regional brachiopod taxa played a significant role in defining the paleobiogeographic pattern of the ***,the first brachiopod radiation was asso-ciated with 3 major pulses of onshore migration from the upper Jiangnan Slope through the central Upper Yang-tze Platform to the near shore settings of the platform,with the middle pulse being the most ***,paleogeographic dispersal took place in both onshore and offshore directions,although the onshore expansion was more prominent;several key brachiopods,such as Paralenorthis,Nocturnellia,Protoskenidioides,Nere-idella,Euorthisina and Yangtzeella,first appeared on the upper Jiangnan Slope and later formed distinct,and taxonomically diverse,communities on the Upper Yangtze *** paleogeographic dispersal of brachio-pods is considered to be closely related to the tectonic evolution of the Qianzhong Arch.

关键词： biotic radiation brachiopod fauna China Ordovician paleogeography

Microstructure and mechanical properties of 2219 aluminum alloy VPTIG welds during cyclic thermal treatment

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Rare Metals 2022年第10期41卷 3539-3545页

作者： Di-Yao su Hui-jin jin su-Jun Wu School of Materials Scienceand Engineering Beihang UniversityBeijing 100191China

In this study,the effect of the cyclic thermal treatment(CTT) on the microstructure and mechanical properties of the 2219 Al alloy welds fabricated using variable polarity tungsten inert gas(VPTIG) arc welding method were investigated by optical microscope(OM),transmission electron microscope(TEM),and low-temperature tensile tests,with emphasis on precipitation evolution and property variation in different areas of the *** of the microhardness profile across the weld reveals that there are maximum and minimum hardness values in the heat-affected zone(HAZ) adjacent to the fusion boundary(FB).It is found that the maximum hardness value increases with the temperature cycles of the cyclic thermal treatment due to the formation of GuinierPreston(GP) zones,while the microhardness at other positions remains *** results show that the CCT results in an increase in the yield strength,but a decrease in the ductility of the weld joint.

关键词： 2219 aluminum alloy VPTIG weld Microstructure Microhardness