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Chemical Research in Chinese Universities 2021年第2期37卷 274-279页

作者： ZHOU Xi LAI Yangyang WU Xiangjiang CHEN Zhongxue ZHONG Faping al xinping YANG Hanxi CAO Yuliang Engineering Research Center of Organosilicon Compounds and Materials of Ministry of Education College of Chemistry and Molecular SciencesWuhan UniversityWuhan430072P.R.China Key Laboratory of Hydraulic Machinery Transients Ministry of EducationSchool of Power and Mechanical EngineeringWuhan UniversityWuhan430072P.R.China National Engineering Research Center of Advanced Energy Storage Materials Hunan410205P.R.China

Sodium-ion batteries(SIBs)are promising for grid-scale energy storage applications due to the natural abundance and low cost of *** various Na insertion cathode materials,Na0.44MnO2 has attracted the most attention because of its cost effectiveness and structural ***,the low initial charge capacity for Na-poor Na0.44MnO2 hinders its practical ***,we developed a facile chemical presodiated method using sodiated biphenly to transform Na-poor Na0.44MnO2 into Na-rich *** presodiation,the initial charge capacity of Na0.44MnO2 is greatly enhanced from 56.5 mA·h/g to 115.7 mA·h/g at 0.1 C(1 C=121 mA/g)and the excellent cycling stability(the capacity retention of 94.1%over 200 cycles at 2 C)is *** presodiation strategy would open a new avenue for promoting the practical applications of Na-poor cathode materials in sodium-ion batteries.

关键词： Sodium-ion battery Na0.44MnO2 Chemical presodiation Sodium biphenyl Initial charge capacity

森林火灾救援直升机吊桶灭火任务调度优化研究

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消防科学与技术 2024年第4期43卷 535-540页

作者：徐浩瞿菁菁王明惠朱新平中国民用航空飞行学院四川广汉618307

鉴于森林火灾突发性强、处置困难等特点及火灾救援中直升机任务调度效率有待提高的现状,为降低森林火灾造成的损失,研究直升机吊桶灭火任务调度优化的方法。结合火场面积、火情状况、救援力量等因素,建立火场空域栅格模型。针对森林火... 详细信息

鉴于森林火灾突发性强、处置困难等特点及火灾救援中直升机任务调度效率有待提高的现状,为降低森林火灾造成的损失,研究直升机吊桶灭火任务调度优化的方法。结合火场面积、火情状况、救援力量等因素,建立火场空域栅格模型。针对森林火灾场景中火场动态变化的情况,提出一种基于深度强化学习(DQN)的动态任务调度优化方法,该方法通过对起火栅格的燃烧时间约束、灭火所需水量等属性进行实时量化,不断更新全局环境,形成动态决策依据,生成任务调度方案,提升直升机吊桶灭火的效率。仿真结果表明,与传统算法中表现较好的贪婪算法相比,本文方法能在火场动态变化的场景下,降低了13.9%的火灾损失率,有效减少了森林火灾造成的资源损失。

关键词：任务调度深度强化学习应急救援动态决策直升机吊桶

Distributed robust power control in two-tier vehicle networks under uncertain channel environments

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Digital Communications and Networks 2023年第3期9卷 734-742页

作者： Zhixin Liu Jiawei Su Yuan-ai Xie Yazhou Yuan Yi Yang xinping Guan School of Electrical Engineering Yanshan UniversityQinhuangdao066004China School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai200240China

This paper proposes a novel optimization scheme to support stable and reliable vehicle-to-everything connections in two-tier networks,where the uplink channel of the cellular user is reused by underlay vehicle-to-vehicle ***,considering complex channel fading and high-speed vehicle movement,the cer-tainty assumption is impractical and fails to maintain power control strategy in reality in the traditional statical vehicular *** than the perfect channel state information assumption,the first-order Gauss-Markov process which is a probabilistic model affected by vehicle speed and fading is introduced to describe imperfect channel ***,interference management is a major challenge in reusing communications,especially in uncertain channel *** control is an effective way to realize interference management,and optimal power allocation can ensure that interference of the user meets the communication *** this study,the sum-rate-oriented power control scheme and minimum-rate-oriented power control scheme were implemented to manage interference and satisfy different design *** both of these schemes are non-convex and intractable,the Bernstein approximation and successive convex approximation methods were adopted to transform the original problems into convex ***,a novel distributed robust power control al-gorithm was developed to determine the optimal *** performance of the algorithm was evaluated through numerical simulations,and the results indicate that the proposed algorithm is effective in vehicular communication networks with uncertain channel environments.

关键词： Vehicle-to-Everything communications Vehicular two-tier networks Channel uncertainty Power control

Group 3 innate lymphoid cells: intestinal patrolling guardians bullied by T cells

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Cellular & Molecular Immunology 2023年第2期20卷 115-116页

作者： xinping Lv Shan Zhu Jing Wu Jingtao Chen Cancer Center First Hospital of Jilin UniversityChangchun130021JilinChina Laboratory for Tumor Immunology First Hospital of Jilin UniversityChangchun130061JilinChina

Since the discovery of group 3 innate lymphoid cells(ILC3s),many studies have reported that,in addition to T cells,ILC3s also play an indispensable role in intestinal immune surveillance,host defense,and homeostasis[1].although both ILC3s and T cells regulate intestinal inflammation through the secretion of interleukin(IL)-22,differences in the behaviors of these two cell types,especially the dynamic shift and mechanism of ILC3 regulation between normal and inflammatory states,remain unclear.A recent paper by Jarade et al.[2]published in Nature Immunology reported that intestinal ILC3s under basal conditions are immotile and arrested in the presence of T ***,the environmental T cells,the microbiota,and the chemokine CCL25 jointly shape ILC3 patrolling behavior and their effector function of maintaining intestinal barrier integrity via *** findings facilitate the study of ILC biodynamics and ILC immune regulation and the search for therapeutic strategies for gastrointestinal diseases.

关键词： lymphoid jointly guard

喷砂工艺对Y-TZP力学性能和表面粗糙度的影响

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中国锰业 2024年第1期42卷 72-76页

作者：林信平陈戈杨清平李和祯比亚迪股份有限公司广东深圳518118 惠州比亚迪电子有限公司广东惠州516083

为了评估不同喷砂工艺对氧化锆陶瓷力学性能和表面粗糙度的影响,采用不同的喷砂处理工艺对样品进行喷砂处理。研究表明氧化锆陶瓷经过喷砂处理后表层单斜相含量明显增加。喷砂原料的颗粒尺寸越大,相变越多。喷砂后表面粗糙度增加,在相... 详细信息

为了评估不同喷砂工艺对氧化锆陶瓷力学性能和表面粗糙度的影响,采用不同的喷砂处理工艺对样品进行喷砂处理。研究表明氧化锆陶瓷经过喷砂处理后表层单斜相含量明显增加。喷砂原料的颗粒尺寸越大,相变越多。喷砂后表面粗糙度增加,在相同的喷砂条件下,经球形al_(2)O_(3)处理的样品表面粗糙度Sa远小于经SiC颗粒处理的。在喷砂原料粒径为100μm、喷砂时间为20 s、压力为0.2 MPa的情况下,四点弯曲强度分别提高了27%(SiC)与21%(al_(2)O_(3))。因此,具有球形颗粒形貌的al_(2)O_(3)颗粒更适合用作表面喷砂处理。

关键词：四方多晶氧化锆喷砂相转变弯曲强度表面粗糙度

Distribution behavior of inclusions in compact-strip-produced martensitic steel and its influence on mechanical properties

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Journal of Materials Science & Technology 2023年第11期142卷 98-111页

作者： Jing Wang Peng Xue Laiqi Zhang Li You Xiaodong Zhu Shuize Wang Yong Zhong xinping Mao State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Research Institute Baoshan Iron&Steel Co.LtdShanghai 201999China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China

The distribution behavior of inclusions in martensitic steel produced by compact strip production process(CSP-MS)and its influence on mechanical properties were systematically *** inclusions in the CSP-MS specimen are mainly composed of spherical al_(2)O_(3)-CaO-CaS,MnS with high aspect ratio and small-sized TiN,whereas many coarse cuboidal TiN inclusions do exist in conventional martensitic steel(Con-MS).The high inclusion density of the CSP-MS specimen resulted in lower total elongation and impact toughness,and the MnS inclusions with high aspect ratio led to significantly stronger mechanical anisotropy than that for Con-MS *** in-situ tensile results indicated that when the fracture direction is parallel to MnS direction,the microcracks induced by MnS inclusions tend to propagate into the matrix,leading to the formation of valley-like features,which significantly deteriorate the properties such as the total elongation and impact *** microcracks caused by TiN inclusions are sharper than those caused by spherical al_(2)O_(3)-CaO-CaS inclusions,and are easy to propagate into the *** work is expected to guide the optimization of the mechanical properties of martensitic steels produced by CSP process and provide a theoretical basis for the CSP process design.

关键词： Martensitic steel Compact strip production Inclusion distribution behavior Mechanical properties In-situ tensile test

硅和镁质量分数对al-Si-Mg合金机械力学性能参数影响的计算分析

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齐鲁工业大学学报 2024年第4期38卷 30-35页

作者：郭柔刘文豪薛预超马瑞杰胡心平齐鲁工业大学(山东省科学院)机械工程学部山东济南250353

基于第一性原理,利用CASTEP模块,通过虚拟晶体近似的方法建模,采用GGA+PBE泛函关联函数,研究了al-Si7-Mg X(X=0.1~0.5)、al-Si X-Mg0.3(X=6~9)合金中的Si、Mg质量分数的变化对机械力学性能参数的影响。研究表明,随着研究组元质量分数的... 详细信息

基于第一性原理,利用CASTEP模块,通过虚拟晶体近似的方法建模,采用GGA+PBE泛函关联函数,研究了al-Si7-Mg X(X=0.1~0.5)、al-Si X-Mg0.3(X=6~9)合金中的Si、Mg质量分数的变化对机械力学性能参数的影响。研究表明,随着研究组元质量分数的增加,晶格常数有所减小,最大值与最小值相差约0.265%;弹性常数C_(11)、C_(12)、C_(44)满足结构稳定性条件;体积模量B、剪切模量G、杨氏模量E、泊松比u随着A356中Si、Mg质量分数变化而变化;Mg质量分数的变化对剪切模量G、杨氏模量E的影响比Si质量分数的变化更敏感。计算结果与现有实验数据对比表明,计算结果接近实验数据,第一性原理计算al-Si-Mg合金材料参数可行。

关键词：第一性原理 al-Si-Mg 晶格常数弹性模量泊松比

A positive-temperature-coefficient electrode with thermal protection mechanism for rechargeable lithium batteries

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Chinese Science Bulletin 2012年第27期57卷 4205-4209页

作者： XIA Lan ZHU LiMin ZHANG HaiYan AI xinping Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry&Molecule ScienceWuhan UniversityWuhan 430072China

A new positive-temperature-coefficient(PTC) material was prepared simply by blending of conductive Super P carbon black(CB) with insulating poly(methyl methacrylate)(PMMA) polymer matrix,which was empolyed as a coating layer on the aluminium foil substrate to fabricate a sandwiched al/PTC/LiCoO2 *** experimental results from cyclic voltammetry,charge-discharge measurements and impedance spectroscopy demonstrated that the PTC electrode has a normal electrochemical performance at ambient temperature,but shows an enormous increase in the resistance at the temperature range of 80?120℃.This PTC behavior greatly restrains the reaction current passing through the electrode at elevated temperatures,capable of acting as a self-actuating safety mechanism to prevent the battery from thermal runaway.

关键词：正温度系数电池电极聚(甲基丙烯酸甲酯) 保护机制可充电 PTC特性聚合物基体循环伏安法

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Effect of dispersion and distribution of tungsten on W/HZSM-5 for selective catalytic reduction of NO by acetylene

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Journal of Natural Gas Chemistry 2008年第4期17卷 332-336页

作者： Ran Bi xinping Wang Zhiguang Liu Jing Chen State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116024 Liaoning China

Catalytic performance of W/HZSM-5 in selective catalytic reduction of NO by acetylene was investigated in a reaction system with 1600 ppm of NO, 800 ppm of C2H2, and 9.95% of O2 in He. It was found that promotional effect of tungsten on the reaction is strongly affected by catalyst preparation conditions and Si/al ratio of the parent zeolite. A better dispersion of tungsten on HZSM-5 and relatively more monomeric tungsten species were found on 8%W/HZSM-5 prepared by impregnation of the zeolite with lower SiO2/A1203 ratio （25） in ammonic ammonium tungstate solution and calcination of the resulting material at higher temperature （550 ℃）. The highest NO conversion to N2 of 86.3% in the reaction system was obtained at 350 ℃ over the catalyst thus prepared. The mechanism of monomeric tungsten species improving the C2H2-SCR can be attributed to accelerating the formation of active nitrate species.

关键词： nitric oxide selective catalytic reduction tungsten HZSM-5

Temperature change and stress distribution analysis of die surface in al-alloy die casting process and experimental study on die heat check

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China Foundry 2008年第1期5卷 47-53页

作者： Hu xinping Zhao Guoqun Wu Bingyao School of Material Science and Engineering Shandong University Jinan 250061 China School of Mechanical Engineering Shandong Institute of Light Industry Jinan 250353 China School of Material Science and Engineering Southeast University Nanjing 210096 China

The temperature change of the die surface in practical aluminum alloy die casting process was analyzed,and a 2D model was formulated on the basis of a deep concave round cavity without sliding core to analyze thestress distributions along the die surface in detail. Equipment was designed to test the thermal state of the die steelin different thermal loading conditions. The results of stress analysis showed that, the value of thermal stress (maximum1.5 GPa) caused in the die filling and die spraying stages was larger than the mechanical stress (maximum 85 MPa)caused in the die locking stage. The results of the thermal check experiment showed that there were three stages ofdie dissolving, and that the stress distribution shown by the samples' cracking routine was close to the die surfacestress analysis.

关键词：拉模铸造模具温度变化压力分布