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Inhibiting Voltage Decay in Li-Rich Layered Oxide Cathode: From O3-Type to O2-Type Structural Design

NANO-MICRO LETTERS 2024年第1期16卷 1-22页

作者： zhang, guohua Wen, Xiaohui Gao, Yuheng zhang, Renyuan Huang, Yunhui Tongji Univ Inst New Energy Vehicles Sch Mat Sci & Engn Shanghai Key Lab R&D & Applicat Met Funct Mat Shanghai 201804 Peoples R China Contemporary Amperex Technol Co Ltd Ningde 352100 Peoples R China Huazhong Univ Sci & Technol Sch Mat Sci & Engn State Key Lab Mat Proc & Die & Mould Technol Wuhan 430074 Hubei Peoples R China

This review systematically compares the different effects of O2-type and O3-type structures on voltage decay for Li-rich layered oxide (LRLO) *** development of O2-type materials and the corresponding mechanisms for addressing voltage decay are comprehensively *** perspectives and challenges for designing high-performance O2-type LRLO cathodes without voltage decay are proposed. Li-rich layered oxide (LRLO) cathodes have been regarded as promising candidates for next-generation Li-ion batteries due to their exceptionally high energy density, which combines cationic and anionic redox activities. However, continuous voltage decay during cycling remains the primary obstacle for practical applications, which has yet to be fundamentally addressed. It is widely acknowledged that voltage decay originates from the irreversible migration of transition metal ions, which usually further exacerbates structural evolution and aggravates the irreversible oxygen redox reactions. Recently, constructing O2-type structure has been considered one of the most promising approaches for inhibiting voltage decay. In this review, the relationship between voltage decay and structural evolution is systematically elucidated. Strategies to suppress voltage decay are systematically summarized. Additionally, the design of O2-type structure and the corresponding mechanism of suppressing voltage decay are comprehensively discussed. Unfortunately, the reported O2-type LRLO cathodes still exhibit partially disordered structure with extended cycles. Herein, the factors that may cause the irreversible transition metal migrations in O2-type LRLO materials are also explored, while the perspectives and challenges for designing high-performance O2-type LRLO cathodes without voltage decay are proposed.

关键词： Lithium-ion batteries Li-rich layered oxide Voltage decay Migration of transition metal ions O2-type structural design RECHARGEABLE LITHIUM BATTERIES ANIONIC REDOX CHEMISTRY ION-EXCHANGE INTERCALATION COMPOUNDS ELECTRONIC-STRUCTURE O2 STRUCTURE CAPACITY ORIGIN CHALLENGES MECHANISM

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3-D Tunnel Seismic Advance Prediction Method with Wide Illumination and High-Precision

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Journal of Earth Science 2024年第3期35卷 970-979页

作者： Peng Guan Cuifa Shao Yuyong Jiao guohua zhang Junpeng Zou Fei Tan Faculty of Engineering China University of GeosciencesWuhan 430074China

Tunnel seismic advance prediction can effectively reduce the construction risk during tunnel *** with the 2-D method,the 3-D method is more conducive to describing the spatial characteristics of the geological body by adding the seismic data in the vertical ***,some drawbacks still need improvement in the current 3-D tunnel seismic prediction method.(1)The geometry is complex,which is destructiveness,high cost,and time-consuming,and will delay the tunnel construction schedule.(2)Illumination of the anomalous body is insufficient,and the precision of migration imaging is low.(3)Shot points are far away from the tunnel face,the energy loss at the shot points is more serious.(4)The received signals at the tunnel wall have the surface wave with strong energy when the shot points are placed on the tunnel wall.(5)The geometry is not linear,so the directional filtering method cannot be used to extract the reflection *** overcome the drawbacks of the current prediction method,a new 3-D symmetrical tunnel seismic prediction method is *** geophones are installed on the tunnel wall,two on the left side,two on the right side,and two on the top ***-four shot points are placed on the tunnel face and near both sides of the tunnel wall,twelve shot points on the left side and twelve shot points on the right *** shot points will move along with the forward excavation of the *** wavefield analysis,illumination statistics,and 3-D reverse time migration imaging are used to evaluate the proposed *** result of modeled data indicates that the proposed 3-D geometry has some advantages:(1)the geometry is simple and the geophone installation time is short;(2)it has high illumination energy,wide illumination range,and can improve the prediction distance and imaging accuracy;(3)the proposed 3-D method can better estimate the velocity of surrounding rock and is more conducive to extracting the reflection wave with high resolut

关键词： tunnels excavation geophone shot points migration imaging method engineering ge-ology.

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Design and optimization of fluid lubricated bearings operated with extreme working performances——a comprehensive review

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International Journal of Extreme Manufacturing 2024年第2期6卷 325-376页

作者： guohua zhang Ming Huang Gangli Chen Jiasheng Li Yang Liu Jianguo He Yueqing Zheng Siwei Tang Hailong Cui Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyangSichuan 621999People’s Republic of China

Fluid lubricated bearings have been widely adopted as support components for high-end equipment in metrology,semiconductor devices,aviation,strategic defense,ultraprecision manufacturing,medical treatment,and power *** all these applications,the equipment must deliver extreme working performances such as ultraprecise movement,ultrahigh rotation speed,ultraheavy bearing loads,ultrahigh environmental temperatures,strong radiation resistance,and high vacuum operation,which have challenged the design and optimization of reliable fluid lubricated *** of any related bottlenecks will promote the development course of high-end *** promote the advancement of high-end equipment,this paper reviews the design and optimization of fluid lubricated bearings operated at typical extreme working performances,targeting the realization of extreme working performances,current challenges and solutions,underlying deficiencies,and promising developmental *** paper can guide the selection of suitable fluid lubricated bearings and optimize their structures to meet their required working performances.

关键词： fluid lubricated bearings structural design performance optimization extreme working performances

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Inhibiting Voltage Decay in Li-Rich Layered Oxide Cathode: From O3-Type to O2-Type Structural Design

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Nano-Micro Letters 2024年第12期 89-110页

作者： guohua zhang Xiaohui Wen Yuheng Gao Renyuan zhang Yunhui Huang Institute of New Energy for Vehicles Shanghai Key Laboratory for R&D and Application of Metallic Functional Materials School of Materials Science and Engineering Tongji University Contemporary Amperex Technology Co. Ltd State Key Laboratory of Material Processing and Die and Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology

Li-rich layered oxide(LRLO) cathodes have been regarded as promising candidates for next-generation Li-ion batteries due to their exceptionally high energy density, which combines cationic and anionic redox activities. However, continuous voltage decay during cycling remains the primary obstacle for practical applications, which has yet to be fundamentally addressed. It is widely acknowledged that voltage decay originates from the irreversible migration of transition metal ions, which usually further exacerbates structural evolution and aggravates the irreversible oxygen redox reactions. Recently, constructing O2-type structure has been considered one of the most promising approaches for inhibiting voltage decay. In this review, the relationship between voltage decay and structural evolution is systematically elucidated. Strategies to suppress voltage decay are systematically summarized. Additionally, the design of O2-type structure and the corresponding mechanism of suppressing voltage decay are comprehensively discussed. Unfortunately, the reported O2-type LRLO cathodes still exhibit partially disordered structure with extended cycles. Herein, the factors that may cause the irreversible transition metal migrations in O2-type LRLO materials are also explored, while the perspectives and challenges for designing high-performance O2-type LRLO cathodes without voltage decay are proposed.

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A novel tunnel seismic prediction method based on threshold trigger

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Journal of Earth Science 2024年

作者： Peng Guan Zhenqiang Shen Cuifa Shao Yuyong Jiao guohua zhang Bin Li Jie Zhou Faculty of Engineering， China University of Geosciences

The tunnel seismic prediction method can provide information on the geological anomalous body in front of the tunnel face in a long distance (120 m)， which has become a necessary work in tunnel construction. The traditional tunnel seismic prediction methods suffer from two main issues: low data acquisition efficiency and the occurrence of signal delay traces during data gathering. These issues， in turn， impact the accuracy of calculating the velocity of the surrounding rock. To address these shortcomings， this paper proposes a new method called the threshold-triggered tunnel seismic prediction method. The effectiveness of the proposed method is validated through the analysis of measured tunnel seismic data. Firstly， when compared with the traditional short-circuit trigger method， the threshold trigger method demonstrates a significant improvement in data acquisition efficiency. Secondly， the threshold triggering mode effectively eliminates the problem of signal delay and jump that is present in the short-circuit trigger mode， thus ensuring the accuracy of the surrounding rock velocity calculation. These advantages clearly demonstrate the potential engineering application value of the threshold-triggered method.

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Laboratory studies on the infectivity of human respiratory viruses:Experimental conditions,detections,and resistance to the atmospheric environment

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Fundamental Research 2024年第3期4卷 471-483页

作者： Yaohao Hu Shuyi Peng Bojiang Su Tao Wang Juying Lin Wei Sun Xiaodong Hu guohua zhang Xinming Wang Ping'an Peng Xinhui Bi State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control Guangzhou 510640China

The environmental stability of infectious viruses in the laboratory setting is crucial to the transmission potential of human respiratory *** experimental techniques or conditions used in studies over the past decades have led to diverse understandings and predictions for the stability of viral infectivity in the atmospheric *** this paper,we review the current knowledge on the effect of simulated atmospheric conditions on the infectivity of respiratory viruses,mainly focusing on influenza viruses and coronaviruses,including severe acute respiratory syndrome coronavirus 2 and Middle East respiratory syndrome ***,we summarize the impact of the experimental conditions on viral stability;these involve the methods of viral aerosol generation,storage during aging and collection,the virus types and strains,the suspension matrixes,the initial inoculum volumes and concentrations,and the drying ***,we summarize and discuss the detection methods of viral infectivity and their ***,we integrate the results from the reviewed studies to obtain an overall understanding of the effects of atmospheric environmental conditions on the decay of infectious viruses,especially aerosolized ***,this review highlights the knowledge gaps in predicting the ability of viruses to maintain infectivity during airborne transmission.

关键词： Respiratory viruses Viral infectivity Laboratory simulation Atmospheric environmental condition Airborne transmission

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围长为8的较大列重准循环低密度奇偶校验码的行重普适代数构造

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电子与信息学报 2024年第7期46卷 3019-3025页

作者：张国华秦煜娄蒙娟方毅西安邮电大学西安710121 广东工业大学广州510006

适合于任意行重(即行重普适(RWU))的无小环准循环(QC)低密度奇偶校验(LDPC)短码,对于LDPC码的理论研究和工程应用具有重要意义。具有行重普适特性且消除4环6环的现有构造方法,只能针对列重为3和4的情况提供QC-LDPC短码。该文在最大公约... 详细信息

适合于任意行重(即行重普适(RWU))的无小环准循环(QC)低密度奇偶校验(LDPC)短码,对于LDPC码的理论研究和工程应用具有重要意义。具有行重普适特性且消除4环6环的现有构造方法,只能针对列重为3和4的情况提供QC-LDPC短码。该文在最大公约数(GCD)框架的基础上,对于列重为5和6的情况,提出了3种具有行重普适特性且消除4环6环的构造方法。与现有的行重普适方法相比,新方法提供的码长从目前的与行重呈4次方关系锐减至与行重呈3次方关系,因而可以为QC-LDPC码的复合构造和高级优化等需要较大列重基础码的场合提供行重普适的无4环无6环短码。此外,与基于计算机搜索的对称结构QC-LDPC码相比,新码不仅无需搜索、描述复杂度更低,而且具有更好的译码性能。

关键词：低密度奇偶校验码准循环围长最大公约数

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岩石节理接触特征尺寸效应的数值试验研究

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岩土工程学报 2024年第7期46卷 1481-1490页

作者：龚耕李升连张国华熊峰唐志成中国地质大学(武汉)工程学院湖北武汉430074 云南建设基础设施投资股份有限公司云南昆明650032 地质探测与评估教育部重点实验室湖北武汉430074

为探究岩石节理接触特征尺寸效应,采用自仿射分形方法构建系列尺寸数值模型,利用离散弹塑性计算方法求解闭合变形,定量分析节理接触特征尺寸效应规律,并探究不同岩性和粗糙度对其尺寸效应的影响差异。自仿射分形方法构建的岩石节理其粗... 详细信息

为探究岩石节理接触特征尺寸效应,采用自仿射分形方法构建系列尺寸数值模型,利用离散弹塑性计算方法求解闭合变形,定量分析节理接触特征尺寸效应规律,并探究不同岩性和粗糙度对其尺寸效应的影响差异。自仿射分形方法构建的岩石节理其粗糙程度随尺寸增加逐渐变小,接触面积比和组合形貌微凸体参数之间具有关联,接触面积比的尺寸效应可归因于组合形貌微凸体参数ηR的尺寸变化。岩石节理尺寸越大,闭合变形引起的塑性部分占比越多。塑性变形对接触面积比尺寸效应具有弱化作用,对闭合变形尺寸效应具有强化作用,硬岩节理的接触特征尺寸效应强于软岩节理,其接触特征代表性长度也更大。岩石节理的粗糙度对其闭合变形和接触面积比的尺寸效应具有相反的效果。

关键词：岩石节理自仿射分形尺寸效应接触特征

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基于ST-DBSCAN聚类算法的矿井冲击地压微震监测数据时空特性分析

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能源与环保 2024年第7期46卷 62-70页

作者：张国华河南能源集团有限公司河南郑州450046

矿井冲击地压是地下矿山中的一种常见地质灾害,对矿山的安全生产和员工的人身安全造成威胁。矿井常规的数据分析多采用数理统计方法进行危险预警分析,具有一定的片面性和局限性,对高维的微震监测数据时空特性分析明显不足,数据分析缺乏... 详细信息

矿井冲击地压是地下矿山中的一种常见地质灾害,对矿山的安全生产和员工的人身安全造成威胁。矿井常规的数据分析多采用数理统计方法进行危险预警分析,具有一定的片面性和局限性,对高维的微震监测数据时空特性分析明显不足,数据分析缺乏实时性,预警分析对特定软件的依赖性过大。为了提高冲击地压的预警能力,提出了一种基于ST-DBSCAN时空聚类算法的方法来分析矿井冲击地压微震监测数据的时空特性,相对于传统聚类算法,该方法表现出更高的鲁棒性。通过矿井真实微震数据验证分析,证明了ST-DBSCAN时空聚类算法能够满足冲击地压微震监测数据时、空、强分析要求,可以识别和分类工作面回采过程中的应力增高区,能够为矿井冲击地压的预警和管理提供决策支持。

关键词：矿井冲击地压微震监测数据 ST-DBSCAN聚类算法时空特性预警

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稳定同位素视角下小麦对汉代以前黄河流域先民主食结构的影响

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中国农史 2024年第4期43卷 87-100页

作者：侯亮亮贺霞霞张国华山西大学考古文博学院山西太原030006 山西大学生命科学学院山西太原030006

小麦何时成为我国先民主食结构的重要组成日益成为学术界广泛关注的重要课题。在植物考古和历史文献证据的基础上,本文对黄河流域小麦传入的关键时段——新石器时代晚期至两汉时期——人骨的C、N稳定同位素数据进行了综合分析,初步勾勒... 详细信息

小麦何时成为我国先民主食结构的重要组成日益成为学术界广泛关注的重要课题。在植物考古和历史文献证据的基础上,本文对黄河流域小麦传入的关键时段——新石器时代晚期至两汉时期——人骨的C、N稳定同位素数据进行了综合分析,初步勾勒出小麦在具体时空范围内对先民食物结构的影响。结果显示,距今4000年至3800年前后,小麦开始对河西走廊地区先民食物结构产生冲击。距今3600年前后,小麦开始对甘肃、河湟及其毗邻地区先民的主食结构产生影响。然而,东周至两汉时期,小麦才对黄河中游地区先民的主食结构产生影响。具体而言,西汉至东汉时期,小麦开始对关中地区先民的主食结构产生明显影响。东周至两汉时期,小麦在今山西和今河南地区先民主食结构中的比重明显上升,显然,本时期是小麦推广的关键时期。这可能与冬小麦和石转磨等的出现及利农政策和人口的飞速增长等因素相关。然而,今内蒙古中南部地区和今山东地区的相关情况还有待进一步研究。未来如何精准判断小麦在先民主食结构中的比重,可能依然是研究中的重点和难点。

关键词：稳定同位素小麦的消费黄河流域东周至两汉

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