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Time-sensitive prediction of NO_(2) concentration in China using an ensemble machine learning model from multi-source data

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Journal of Environmental Sciences 2024年第3期137卷 30-40页

作者： chenliang Tao Man Jia Guoqiang Wang Yuqiang zhang Qingzhu zhang Xianfeng Wang Qiao Wang Wenxing Wang Big Data Research Center for Ecology and Environment Environment Research InstituteShandong UniversityQingdao 266237China Shandong Provincial Eco-environment Monitoring Center Jinan 250101China

Nitrogen dioxide(NO_(2))poses a critical potential risk to environmental quality and public health.A reliable machine learning(ML)forecasting framework will be useful to provide valuable information to support government decision-making.Based on the data from1609 air quality monitors across China from 2014-2020,this study designed an ensemble ML model by integrating multiple types of spatial-temporal variables and three sub-models for time-sensitive prediction over a wide range.The ensemble ML model incorporates a residual connection to the gated recurrent unit(GRU)network and adopts the advantage of Transformer,extreme gradient boosting(XGBoost)and GRU with residual connection network,resulting in a 4.1%±1.0%lower root mean square error over XGBoost for the test results.The ensemble model shows great prediction performance,with coefficient of determination of 0.91,0.86,and 0.77 for 1-hr,3-hr,and 24-hr averages for the test results,respectively.In particular,this model has achieved excellent performance with low spatial uncertainty in Central,East,and North China,the major site-dense zones.Through the interpretability analysis based on the Shapley value for different temporal resolutions,we found that the contribution of atmospheric chemical processes is more important for hourly predictions compared with the daily scale predictions,while the impact of meteorological conditions would be ever-prominent for the latter.Compared with existing models for different spatiotemporal scales,the present model can be implemented at any air quality monitoring station across China to facilitate achieving rapid and dependable forecast of NO_(2),which will help developing effective control policies.

关键词： Air quality prediction Deep learning Ensemble method Nitrogen dioxide Spatiotemporal covariates

Major roles of the circadian clock in cancer

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Cancer Biology & Medicine 2023年第1期20卷 1-24页

作者： Chen Huang chenliang zhang Yubin Cao Jian Li Feng Bi Department of Abdominal Oncology Cancer Center and Laboratory of Molecular Targeted Therapy in OncologyWest China HospitalSichuan UniversityChengdu 610000China Laboratory of Molecular Targeted Therapy in Oncology West China HospitalSichuan UniversityChengdu 610000China Department of Gastroenterology West China HospitalSichuan UniversityChengdu 610000China West China School of Medicine Sichuan UniversityChengdu 610000China

Circadian rhythms are natural rhythms that widely exist in all creatures,and regulate the processes and physiological functions of various biochemical reactions.The circadian clock is critical for cancer occurrence and progression.Its function is regulated by metabolic activities,and the expression and transcription of various genes.This review summarizes the composition of the circadian clock;the biological basis for its function;its relationship with,and mechanisms in,cancer;its various functions in different cancers;the effects of anti-tumor treatment;and potential therapeutic targets.Research in this area is expected to advance understanding of circadian locomotor output cycles kaput(CLOCK)and brain and muscle ARNT-like protein 1(BMAL1)in tumor diseases,and contribute to the development of new anti-tumor treatment strategies.

关键词： Circadian clock BMAL1 cancer tumor therapy oncology

Balancing electron transfer and intermediate adsorption ability of metallic Ni-Fe-RE-P bifunctional catalysts via 4f-2p-3d electron interaction for enhanced water splitting

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Journal of Energy Chemistry 2024年第7期94卷 458-465页

作者： Hong-Rui Zhao Cheng-Zong Yuan chenliang Zhou Wenkai Zhao Lunliang zhang Cong-Hui Li Lei Xin Fuling Wu Shufeng Ye Xiaomeng zhang Yunfa Chen School of Rare Earths University of Science and Technology of ChinaHefei 230026AnhuiChina Jiangxi Province Research Institute of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou 341119JiangxiChina State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Balancing electron transfer and intermediate adsorption ability of bifunctional catalysts via tailoring elec-tronic structures is crucial for green hydrogen production,while it still remains challenging due to lack-ing efficient strategies.Herein,one efficient and universal strategy is developed to greatly regulate electronic structures of the metallic Ni-Fe-P catalysts via in-situ introducing the rare earth(RE)atoms(Ni-Fe-RE-P,RE=La,Ce,Pr,and Nd).Accordingly,the as-prepared optimal Ni-Fe-Ce-P/CC self-supported bifunctional electrodes exhibited superior electrocatalytic activity and excellent stability with the low overpotentials of 247 and 331 mV at 100 mA cm^(-2) for HER and OER,respectively.In the assem-bled electrolyzer,the Ni-Fe-Ce-P/cC as bifunctional electrodes displayed low operation potential of 1.49 V to achieve a current density of 10 mA cm^(-2),and the catalytic performance can be maintained for 10o h.Experimental results combined with density functional theory(DFT)calculation reveal that Ce doping leads to electron decentralization and crystal structure distortion,which can tailor the band structures and d-band center of Ni-Fe-P,further increasing conductivity and optimizing intermediate adsorption energy.Our work not only proposes a valuable strategy to regulate the electron transfer and intermediate adsorption of electrocatalysts via RE atoms doping,but also provides a deep under-standing of regulation mechanism of metallic electrocatalysts for enhanced water splitting.

关键词： RE atoms Electron transfer Adsorption energy Oxygen evolution Hydrogen evolution

Observations and computations of narrow Kelvin ship wakes

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Journal of Ocean Engineering and Science 2016年第1期1卷 52-65页

作者： Francis Noblesse chenliang zhang Jiayi He Yi Zhu Chenjun Yang Wei Li State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean&Civil EngineeringShanghai Jiao Tong UniversityShanghaiChina

Computations of far-field ship waves,based on linear potential flow theory and the Hogner approximation,are reported for monohull ships and catamarans.Specifically,far-field ship waves are computed for six monohull ships at four Froude numbers F≡V/√gL=0.58,0.68,0.86,1.58 and for six catamarans with nondimensional hull spacing s≡S/L=0.25 at two Froude numbers F s≡V/√gS=1 and 2.5.Here,g is the gravitational acceleration,V and L denote the ship speed and length,and S is the separation distance between the twin hulls of a catamaran.The computations show that,although the amplitudes of the waves created by a ship are strongly influenced by the shape of the ship hull,as well known,the ray angles where the largest waves are found are only weakly influenced by the hull shape and indeed are mostly a kinematic feature of the flow around a ship hull.An important practical consequence of this flow feature is that the apparent wake angle of general monohull ships or catamarans(with arbitrarily-shaped hulls)can be estimated,without computations,by means of simple analytical relations;these relations,obtained elsewhere via parametric computations,are given here.Moreover,the influence of the two parameters F s and s that largely determine the ray angles of the dominant waves created by a catamaran is illustrated via computations for three catamarans with hull spacings s=0.2,0.35,0.5 at four Froude numbers F s=1,1.5,2,2.5.These computations confirm that the largest waves created by wide and/or fast catamarans are found at ray angles that only depend on F s(i.***.that do not depend on the hull spacing s)in agreement with an elementary analysis of lateral interference between the dominant waves created by the bows(or sterns)of the twin hulls of a catamaran.The dominant-waves ray angles predicted by the theory of wave-interference effects for monohull ships and catamarans are also compared with the observations of narrow Kelvin ship wakes reported by Rabaud and Moisy,and found to be consistent with these observations.

关键词： Kelvin wake Narrow ship wake Monohull ship Catamaran Wave interference Bow wave Stern wave.

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水凝胶对三元锂电池热失控抑制效果研究

中国安全科学学报 2024年第5期34卷 186-194页

作者：刘淳元张国维杨林欧阳晨亮张作睿中国矿业大学深圳研究院广东深圳518057 中国矿业大学安全工程学院江苏徐州221116 北京市海淀区消防救援支队北京100080

为快速有效扑灭锂离子电池火灾,解决灭火时间长、耗水量大等消防领域关注的难题,探究水凝胶灭火剂对大容量锂离子电池热失控的抑制效果。首先,借助环境扫描电镜,分析水凝胶在高温下微观结构的变化;然后,搭建锂电池燃烧试验平台,开展水... 详细信息

为快速有效扑灭锂离子电池火灾,解决灭火时间长、耗水量大等消防领域关注的难题,探究水凝胶灭火剂对大容量锂离子电池热失控的抑制效果。首先,借助环境扫描电镜,分析水凝胶在高温下微观结构的变化;然后,搭建锂电池燃烧试验平台,开展水凝胶灭火试验;最后,以车用135 Ah方形铝壳三元锂电池组为试验对象,采用电加热的方法诱导其发生热失控,探究水凝胶对锂电池的降温抑制效果。结果表明:水凝胶受热后,内部孔状结构被破坏,有利于其黏附在物体表面持续降温;使用水凝胶灭火降温时,电池表面最大降温速率是水的2倍,水凝胶喷放结束后,锂电池温度回升速率较为缓慢,升温速率仅为水的一半;与水相比,水凝胶延缓相邻电池发生热失控的时间更长,这可以为救援逃生带来更长的安全时间。

关键词：水凝胶热失控三元锂电池抑制效果降温速率安全时间

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共价有机框架材料在质子交换膜中的应用

化学进展 2024年第1期36卷 48-66页

作者：张炜煜李杰李红姬佳奇宫琛亮丁三元兰州大学化学化工学院功能有机分子化学国家重点实验室兰州730000

共价有机框架(COFs)作为一种新型有机多孔材料,具有高度结晶性、有序的多孔排列、功能可修饰性、结构可调性以及较高稳定性。COFs规整的孔道可以容纳多种质子载流子和质子供体,构建连续稳定的质子传输通道,在含水质子传导与无水质子传... 详细信息

共价有机框架(COFs)作为一种新型有机多孔材料,具有高度结晶性、有序的多孔排列、功能可修饰性、结构可调性以及较高稳定性。COFs规整的孔道可以容纳多种质子载流子和质子供体,构建连续稳定的质子传输通道,在含水质子传导与无水质子传导中均发挥巨大的作用,将COFs应用到质子交换膜领域具有重要的研究意义和价值。本文分别从COFs作为低温燃料电池质子交换膜和高温燃料电池质子交换膜两方面,总结了COFs固态电解质膜、COFs与高分子基质复合膜、COFs自支撑膜等不同种类质子交换膜的特点以及提高COFs质子交换膜性能的改性方法,综述了近年来COFs在燃料电池质子交换膜领域的相关代表性研究。最后,对COFs质子交换膜的应用前景进行了讨论与展望。

关键词：共价有机框架质子交换膜质子传导

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基于超分子相互作用的自愈合聚氨酯材料

精细化工 2024年第3期41卷 499-508,606页

作者：王陈亮杨建军吴庆云吴明元张建安刘久逸安徽大学化学化工学院安徽省水基高分子材料高性能化工程实验室安徽合肥230601

聚氨酯材料由于其固有的氢键结构被认为是一种理想的自愈合材料。将超分子化学体系引入到聚氨酯中,可以获得性能更加出色的自愈合材料。这些基于超分子相互作用的自愈合聚氨酯材料在受损后能够恢复其大部分物理和化学性质,具有优异的性... 详细信息

聚氨酯材料由于其固有的氢键结构被认为是一种理想的自愈合材料。将超分子化学体系引入到聚氨酯中,可以获得性能更加出色的自愈合材料。这些基于超分子相互作用的自愈合聚氨酯材料在受损后能够恢复其大部分物理和化学性质,具有优异的性能。该文首先从不同类型的愈合机理出发,综述了近年来基于超分子相互作用的自愈合聚氨酯材料,包括氢键结合体系、基于芳香基的π-π堆积体系、链段侧链中含有离子基团并彼此形成交联点的离子交联聚合物体系、金属离子与配体进行配位引起材料交联的金属配体相互作用体系、大环分子与特定大小的分子形成包合物的主客互动体系。然后展望了自愈合聚氨酯未来发展优势。

关键词：自愈合聚氨酯超分子作用动态键氢键配位键

基于Hadoop技术的气象数据实时传输监控系统设计

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计算机测量与控制 2024年第1期32卷 114-120页

作者：陶淘彭颖张晨亮新疆维吾尔自治区气象信息中心乌鲁木齐830002 西南民族大学计算机科学与工程学院成都610041 新疆维吾尔自治区气象技术装备保障中心乌鲁木齐830002

气象数据在传输过程中,可能会出现数据丢失、重复、错误等问题,为准确分析气象问题表现情况,实现对气象问题的实时监控,设计了基于Hadoop技术的气象数据实时传输监控系统;联合JTAG调试电路与数据采集器,调节风速风向、雨雪、雷电、温湿... 详细信息

气象数据在传输过程中,可能会出现数据丢失、重复、错误等问题,为准确分析气象问题表现情况,实现对气象问题的实时监控,设计了基于Hadoop技术的气象数据实时传输监控系统;联合JTAG调试电路与数据采集器,调节风速风向、雨雪、雷电、温湿度4个基础监控模块,完成气象数据实时传输监控系统的硬件设计;根据Hadoop架构体系连接形式,搭建Hadoop架构体系,预处理气象数据;在此基础上,匹配数据库机制与业务信息表单,实现应用系统的实时传输监控功能,再联合相关系统硬件,完成基于Hadoop技术的气象数据实时传输监控系统的设计;实验结果表明,在文章设计系统作用下,A、B、C三个场景的风力、降雨、降雪、雷电等级监控结果均与气象数据取样结果保持一致,能够有效实现对风、雨、雪、雷4种气象问题的实时监测,可以准确分析气象问题表现情况,且平均响应时间仅为61.3 ms,具有较好的实时性。

关键词： Hadoop技术气象数据传输监控系统 JTAG电路数据采集器数据库业务信息表气象问题

BOPPPS模型在“信号与系统”教学中的应用

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电气电子教学学报 2024年第1期46卷 104-106页

作者：孙雪丽张晨亮张亚周海军航空大学烟台264001

按照军队院校课程思政教学的基本要求,以“信号与系统”课程中的“连续时间系统的描述与模拟”知识点为例,深入挖掘教学内容中的思政元素,采用BOPPPS模型进行课堂教学的设计与实施,并从教学内容分析、思政元素挖掘、思政元素融入、教学... 详细信息

按照军队院校课程思政教学的基本要求,以“信号与系统”课程中的“连续时间系统的描述与模拟”知识点为例,深入挖掘教学内容中的思政元素,采用BOPPPS模型进行课堂教学的设计与实施,并从教学内容分析、思政元素挖掘、思政元素融入、教学设计和教学效果评价等方面进行了探讨。

关键词： BOPPPS模型思政教学信号与系统