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Excitonic devices based on two-dimensional transition metal dichalcogenides van der Waals heterostructures

Frontiers of Chemical Science and Engineering 2024年第2期18卷 41-67页

作者： Yulun Liu Yaojie Zhu Zuowei Yan Ruixue Bai xilin zhang Yanbo Ren Xiaoyu Cheng Hui Ma Chongyun Jiang College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350China School of Physical Science and Technology Tiangong UniversityTianjin 300387China

Excitonic devices are an emerging class of technology that utilizes excitons as carriers for encoding, transmitting, and storing information. Van der Waals heterostructures based on transition metal dichalcogenides often exhibit a type II band alignment, which facilitates the generation of interlayer excitons. As a bonded pair of electrons and holes in the separation layer, interlayer excitons offer the chance to investigate exciton transport due to their intrinsic out-of-plane dipole moment and extended exciton lifetime. Furthermore, interlayer excitons can potentially analyze other encoding strategies for information processing beyond the conventional utilization of spin and charge. The review provided valuable insights and recommendations for researchers studying interlayer excitonic devices within van der Waals heterostructures based on transition metal dichalcogenides. Firstly, we provide an overview of the essential attributes of transition metal dichalcogenide materials, focusing on their fundamental properties, excitonic effects, and the distinctive features exhibited by interlayer excitons in van der Waals heterostructures. Subsequently, this discourse emphasizes the recent advancements in interlayer excitonic devices founded on van der Waals heterostructures, with specific attention is given to the utilization of valley electronics for information processing, employing the valley index. In conclusion, this paper examines the potential and current challenges associated with excitonic devices.

关键词： excitonic devices van der Waals heterostructures transition metal dichalcogenides interlayer excitons valley-Hall effect optoelectronics

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Conversion of Lignin into Porous Carbons for High-Performance Supercapacitors via Spray Drying and KOH Activation: Structure-Properties Relationship and Reaction Mechanism

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Journal of Renewable Materials 2024年第7期12卷 1207-1218页

作者： Shihao Feng Qin Ouyang Jing Huang xilin zhang Zhongjun Ma Kun Liang Qing Huang Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications Ningbo Key Laboratory of Special Energy Materials and ChemistryNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China Engineering Laboratory of Advanced Energy Materials Qianwan Institute of CNITECHNingbo315336China School of Physics Henan Normal UniversityXinxiang453007China School of Environment Henan Normal UniversityXinxiang453007China

Lignin-derived porous carbons have emerged as promising electrode materials for ***,the challenge remains in designing and controlling their structure to achieve ideal electrochemical performance due to the complex molecular structure of lignin and its intricate chemical reactions during the activation *** this study,three porous carbons were synthesized from lignin by spray drying and chemical activation with vary-ing KOH *** speciﬁc surface area and structural order of the prepared porous carbon continued to increase with the increase of the KOH ***-mass spectrometry(TG-MS)was employed to track the molecular fragments generated during the pyrolysis of KOH-activated lignin,and the mechanism of the thermochemical conversion was *** the thermochemical conversion of lignin,KOH facili-tated the removal of H2 and CO,leading to the formation of not only more micropores and mesopores,but also more ordered carbon *** pore structure exhibited a greater impact than the carbon structure on the electrochemical performance of porous *** optimized porous carbon exhibited a capacitance of 256 F g-1 at a current density of 0.2 A g-1,making it an ideal electrode material for high-performance supercapacitors.

关键词： Lignin porous carbon KOH activation mechanism supercapacitor

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Identification of depressive symptoms:A cause-and-effect based machine learning study

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Chinese Medical Journal 2024年第10期137卷 1258-1260页

作者： Tiantian Wang Zijian zhang xilin zhang Chuang Xue Tingting Cheng Department of Radiation Oncology Xiangya HospitalCentral South UniversityChangshaHunan 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalChangshaHunan 410008China School of Science Hunan University of Technology and BusinessChangshaHunan 410205China School of Mathematical Sciences University of Science and Technology of ChinaHefeiAnhui 230026China Department of Physiotherapy Treatment Center Affiliated Mental Health Center&Hangzhou Seventh People’s HospitalZhejiang University School of MedicineHangzhouZhejiang 310000China Department of General Practice Xiangya HospitalCentral South UniversityChangshaHunan 410008China

To the Editor:As society continues to advance,individuals are increasingly exposed to various stressors in their personal and professional *** World Health Organization claims that nearly 1 billion people worldwide suffer from mental disorders in 2019,including 14%of the world’s adolescents.[1]Depression among Chinese adults is a serious public health challenge that requires urgent *** to the combined inuence of various life stresses and unhealthy lifestyles,individuals face a signicantly increased risk of developing depression.[2]Depression is often misdiagnosed because its symptoms overlap with those of other mental health conditions.A misdiagnosis of depression can have a signicant impact on all aspects of an individual’s *** children,a misdiagnosis can lead to inappropriate academic interventions or unnecessary treatments that can adversely affect their school life and overall *** adults,a misdiagnosis can strain relationships.

关键词： continue overlap effect

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基于关节空间位形优选的稳定平台运动学标定

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天津大学学报（自然科学与工程技术版） 2024年第5期57卷 489-500页

作者：田文杰霍明帅张熙临张相鹏天津大学海洋科学与技术学院天津300072 天津大学机械工程学院天津300350

船舶姿态稳定平台装载作业时,其作业精度必须要满足工程实际的需要.传统的方法难以建立包含全部误差源的误差模型,因而针对3-UPS&S姿态稳定平台的运动学标定问题,从关节空间的角度切入,建立了基于驱动关节等效误差的模型,并开展了基于... 详细信息

船舶姿态稳定平台装载作业时,其作业精度必须要满足工程实际的需要.传统的方法难以建立包含全部误差源的误差模型,因而针对3-UPS&S姿态稳定平台的运动学标定问题,从关节空间的角度切入,建立了基于驱动关节等效误差的模型,并开展了基于关节空间的位形优选工作.首先,使用伪误差理论建立了驱动关节等效误差模型,其将稳定平台工作空间各维度相互耦合的姿态误差解耦并转化为关节空间等效驱动关节误差,并借助4阶幂多项式将后者描述为随位形变化的函数,从而构建了稳定平台整机误差辨识模型.其次,采用三坐标测量臂制定姿态误差测量方案,建立可解耦至关节空间的参数辨识方法,并开展离线辨识和误差实时在线补偿.在解耦至关节空间参数辨识的基础上,着重研究如何在关节空间中开展测量位形优选工作,以提升平台的姿态补偿精度.通过对各驱动杆离散化处理获得稳定平台的可达工作范围,而后基于残差分析理论定义了位形优选指标,并采用Exchange-Add-Exchange算法对位形优选的约束问题进行优化分析,利用计算机开展仿真实验获取了最佳测量位形.最后,根据测量方案,采用三坐标测量臂获取样机姿态误差数据并开展误差补偿实验,验证所提方法的正确性和有效性.实验结果表明,稳定平台的姿态体积精度由标定前的0.487°降低为0.065°.

关键词：姿态稳定平台运动学标定等效模型关节空间位形优选

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Image segmentation of exfoliated two-dimensional materials by generative adversarial network-based data augmentation

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Chinese Physics B 2024年第3期33卷 112-117页

作者：程晓昱解晨雪刘宇伦白瑞雪肖南海任琰博张喜林马惠蒋崇云 College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300350China School of Physical Science and Technology Tiangong UniversityTianjin 300387China

Mechanically cleaved two-dimensional materials are random in size and *** atomically thin flakes by human experts is inefficient and unsuitable for scalable *** learning algorithms have been adopted as an alternative,nevertheless a major challenge is a lack of sufficient actual training *** we report the generation of synthetic two-dimensional materials images using StyleGAN3 to complement the ***3Plus network is trained with the synthetic images which reduces overfitting and improves recognition accuracy to over 90%.A semi-supervisory technique for labeling images is introduced to reduce manual *** sharper edges recognized by this method facilitate material stacking with precise edge alignment,which benefits exploring novel properties of layered-material devices that crucially depend on the interlayer *** feasible and efficient method allows for the rapid and high-quality manufacturing of atomically thin materials and devices.

关键词： two-dimensional materials deep learning data augmentation generating adversarial networks

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同时诊断多种精神障碍:基于标签相关性的K近邻多标签学习

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系统科学与数学 2024年第9期44卷 2564-2576页

作者：王甜甜张曦林薛闯卫国谢小良湖南工商大学理学院长沙410205 统计学习与智能计算湖南省重点实验室长沙410205 中国科学技术大学数学科学学院合肥230026 浙江大学医学院附属精神卫生中心(杭州市第七人民医院) 杭州310000 北卡罗来纳大学彭布罗克分校数学与计算机系北卡罗莱来州28372

随着技术、经济和社会的快速发展,人们的生活质量得到了极大的提高.然而,工作和生活的快节奏也带来了巨大的压力.紧张、焦虑和担忧等生活困扰,及其带来的体内化学物质失衡,会给患者带来多种精神障碍问题,如抑郁症、躁郁症和焦虑症.精神... 详细信息

随着技术、经济和社会的快速发展,人们的生活质量得到了极大的提高.然而,工作和生活的快节奏也带来了巨大的压力.紧张、焦虑和担忧等生活困扰,及其带来的体内化学物质失衡,会给患者带来多种精神障碍问题,如抑郁症、躁郁症和焦虑症.精神问题往往同时涉及多种相关的精神障碍.为了解决这些问题,文章提出了一种利用机器学习方法和改进的多标签K近邻(ML-KNN)模型的解决方案:基于标签相关性的多标签学习算法.该算法首先利用FPgrowth算法挖掘样本的多个标签之间的相关性,获得标签的频繁项集.然后构建频繁项集和标签的评分模型和阈值模型.前者用于衡量样本与频繁项集或标签之间的相关程度,后者用于解决与频繁项集或标签相对应的判别阈值,并结合起来预测样本的频繁项集.其次,考虑到标签相关性,还引入高斯权重来量化不同实例之间的距离.最后,为了解决模型预测中可能出现的空标签的问题,还依靠传统的K近邻(KNN)算法对空标签数据进行二次预测,进一步提高了预测精度.该算法首先在公开数据集reuters、scene和emotions上与KNN进行比较,以验证算法的有效性.然后在临床数据集上进行实验,结果显示该算法的F1分数、准确度、α准确度和Rate指数分别达到了63.57%、72.73%、73.17%和70.04%.最后,与该数据集上的每种基准方法的实验结果进行比较,平均性能提升为2.8%,证明该算法合理利用了标签之间的相关性和高斯权重对实例之间的距离进行量化.

关键词：精神疾病多标签学习 K近邻高斯权重标签相关性

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煤矿短距离供电线路防越级异常机械跳闸自动检测方法

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机械与电子 2024年第6期42卷 27-31,37页

作者：张喜麟孙海强晋能控股煤业集团有限公司山西大同037003 北京国力电气科技有限公司北京100070

为避免煤矿供电出现重大事故,确保供电线路安全,提出了煤矿短距离供电线路防越级异常机械跳闸自动检测方法。采用迭代法对观察到的时间序列供电线路数据预处理,剔除其噪声点,获得预处理后的供电线路拟合数据。利用余弦相似性,计算2个供... 详细信息

为避免煤矿供电出现重大事故,确保供电线路安全,提出了煤矿短距离供电线路防越级异常机械跳闸自动检测方法。采用迭代法对观察到的时间序列供电线路数据预处理,剔除其噪声点,获得预处理后的供电线路拟合数据。利用余弦相似性,计算2个供电线路矢量在方向上度量特征之间的异常关联性,得到最终的特征子集,实现对机械跳闸的异常特征提取。将提取到的特征值作为变量,输入到建立的防越级机械跳闸自动检测模型中,计算设备状态量集合和目标函数,完成异常跳闸检测。实验结果表明,所提方法能准确检测出煤矿短距离供电线路防越级异常机械跳闸,及时作出应对措施,保证电力安全稳定运行。

关键词：煤矿短距离供电线路防越级跳闸机械异常自动检测残差序列余弦相似性

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Resource allocation optimization of equipment development task based on MOPSO algorithm

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Journal of Systems Engineering and Electronics 2019年第6期30卷 1132-1143页

作者： zhang xilin TAN Yuejin and YANG Zhiwei College of Systems Engineering National University of Defense TechnologyChangsha 410073China Business School Jiangsu Normal UniversityXuzhou 221116China

Resource allocation for an equipment development task is a complex process owing to the inherent characteristics,such as large amounts of input resources,numerous sub-tasks,complex network structures,and high degrees of *** paper presents an investigation into the influence of resource allocation on the duration and cost of *** models are constructed for the relationships of the resource allocation quantity with the duration and cost of the *** considering the uncertainties,such as fluctuations in the sub-task duration and cost,rework iterations,and random overlaps,the tasks are simulated for various resource allocation *** shortest duration and the minimum cost of the development task are first formulated as the objective *** on a multi-objective particle swarm optimization(MOPSO)algorithm,a multi-objective evolutionary algorithm is constructed to optimize the resource allocation scheme for the development ***,an uninhabited aerial vehicle(UAV)is considered as an example of a development task to test the algorithm,and the optimization results of this method are compared with those based on non-dominated sorting genetic algorithm-II(NSGA-II),non-dominated sorting differential evolution(NSDE)and strength pareto evolutionary algorithm-II(SPEA-II).The proposed method is verified for its scientific approach and *** case study shows that the optimization of the resource allocation can greatly aid in shortening the duration of the development task and reducing its cost effectively.

关键词： resource allocation equipment development task multi-objective particle swarm optimization(MOPSO) develop ment task simulation.

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海洋沉积物碳循环过程数值模型的研究进展

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地球科学 2024年第4期49卷 1431-1447页

作者：徐思南吴自军张喜林孙伟香耿威曹红翟滨孙治雷中国地质调查局青岛海洋地质研究所自然资源部天然气水合物重点实验室山东青岛266237 同济大学海洋地质国家重点实验室上海200092 青岛海洋科学与技术试点国家实验室海洋矿产资源评价与探测技术功能实验室山东青岛266237 青岛市城市排水监测站山东青岛266002

海洋沉积物不仅是各种不同来源有机碳的重要埋藏场所,也是一个十分活跃的生物地球化学反应器,在全球海洋碳循环中扮演着重要角色.相对传统的地球化学测试和定性描述方法,数值模型可以突破时间和空间的限制,定量获取海洋沉积物中各个碳... 详细信息

海洋沉积物不仅是各种不同来源有机碳的重要埋藏场所,也是一个十分活跃的生物地球化学反应器,在全球海洋碳循环中扮演着重要角色.相对传统的地球化学测试和定性描述方法,数值模型可以突破时间和空间的限制,定量获取海洋沉积物中各个碳循环过程的反应速率及其通量,因此日益受到学界的重视.海洋沉积物有机质降解是驱动碳循环最为关键的生物地球化学过程,其释放进入周围孔隙水的溶解无机碳一部分可扩散至沉积物上覆水体,另一部分可与钙、镁等离子沉淀形成自生碳酸盐矿物.首先综述目前主要的3类沉积物有机质降解模型(离散性有机质降解模型、连续性有机质降解模型和Power模型)的建模过程及其在全球海洋沉积物有机质降解过程中的应用;接着从有机质降解相关的初级与次级反应出发,介绍沉积物中与有机质降解相关的地球化学过程反应速率模型的刻画方法,并从碳酸盐平衡体系和同位素质量平衡模式角度,探讨了沉积物有机质降解过程对自生碳酸盐形成及其碳同位素的影响;最后分析了当前阶段数学模型在描述有机质降解过程和自生碳酸盐形成中存在的问题和不足,并在此基础上展望未来亟需加强的研究要点,希企为深入理解海洋碳循环与全球气候变化相互反馈,建立可靠的海洋碳循环和生物地球化学预测系统提供有益的科学支撑.

关键词：海洋沉积物碳循环有机质降解自生碳酸盐形成数值模型海洋地质学

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Recent progress of MXenes as the support of catalysts for the CO oxidation and oxygen reduction reaction

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Chinese Chemical Letters 2020年第4期31卷 931-936页

作者： Yiying zhang xilin zhang Cheng Cheng Zongxian Yang School of Physics Henan Normal UniversityXinxiang 453007China College of Chemistry Key Laboratory of Theoretical&Computational Photochemistry of Ministry of EducationBeijing Normal UniversityBeijing 100875China National Demonstration Center for Experimental Physics Education(Henan Normal University) Xinxiang 453007China

MXenes,the new family of two-dimensional(2D)transition metal carbides/nitrides,can serve as the substrate materials for the catalysts due to the large specific surface area,tunable electronic structures and thermal *** first 2D layered MXene,Ti3C2,was successfully obtained by selective etching of the A element from the MAX phases using hydrofluoric acid(HF)at room temperature in *** this review,we summarize the preparation,structure of MXenes and discuss the recent progress in potential application of MXenes in catalysis,mainly in CO oxidation and oxygen reduction reaction(ORR),from the views of both experimental and theoretical inve *** outlook of the major challenges and future directions on research of MXenes is also included.

关键词： MXenes Catalysis Substrate material CO oxidation ORR

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