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Structural Durability & Health Monitoring 2025年第1期19卷 25-54页

作者： chao zhang Shang-Xi Lai Hua-Ping Wang School of Civil Engineering and Mechanics Lanzhou UniversityLanzhou730000China Key Laboratory of Special Functional Materials and Structural Design Ministry of EducationLanzhou UniversityLanzhou730000China

Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the ***,it is particularly signiﬁcant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientiﬁc basis for structural damage identiﬁcation and dynamic model modiﬁ*** view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and brieﬂy describes how to identify structural damages based on the derived modal *** paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),brieﬂy describes damage identiﬁcation methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artiﬁcial intelligence(AI)methods in the direction of modal parameter recognition and damage identiﬁcation is further *** on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identiﬁcation methods are given to provide scientiﬁc references for the optimized design and functional upgrading of SHM systems.

关键词： Structural health monitoring data information modal parameters damage identiﬁcation AI method

High-selectivity electroreduction of low-concentration CO2 with large concentration fluctuation

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Science China Chemistry 2025年

作者： Mengyu Qi Yanbin Ma chao zhang Bingwei Li Xueqing Yang Zhaolin Shi Simeng Liu Changhua An Jiqing Jiao Tongbu Lu MOE International Joint Laboratory of Materials Microstructure Analysis and Testing CenterInstitute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringSchool of Chemistry and Chemical EngineeringTianjin University of Technology Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University

Electrochemical CO2reduction reaction（CO2RR） has been regarded as one of the most promising solutions to achieving “zero carbon emission”. In most of the CO2RR-related studies, high-purity CO2has been employed as the feed gas; however, in practice, CO2is generally emitted in low concentrations, so it is of great significance to realize high-selectivity electroreduction of low-concentration CO2with large concentration fluctuation. In this work, we constructed a dual-active-site catalyst and successfully achieved CO2local enrichment and conversion for low-concentration CO2. Operando experiments reveal that the catalyst has one type of site for activating CO2and one type of site for binding the reaction intermediates. The dual-active-site catalyst displays a selectivity for formic acid consistently above 97% over a broad potential window（from-0.9 to-1.6 V ***）. Even when fed with a low-concentration CO2stream（volume ratio from 50% down to 10%）, the dual-active-site catalyst could display high activity and selectivity（>91%）. In particular, the selectivity is still above 85% when the CO2volume ratio is as low as 5%. This work offers a feasible route for converting low-concentration CO2via a synergistic effect for dual-active-site catalysts.

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浑水入渗对粗粒土柱孔隙及渗透性影响试验研究

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岩土工程学报 2025年第1期47卷 173-183页

作者：毛海涛张超袁古城何涛谷易山西农业大学城乡建设学院山西太原030000 重庆三峡学院土木工程学院重庆404120

浑水渗流在水利工程的反滤设计、浑水浇灌、堤坝渗流控制等方面都有较大影响,目前理论多采用稳定渗流计算方法,忽略了渗流过程中粗细颗粒与水力的耦合作用。自制渗流装置,将不同控制粒径浑水、不均匀系数粗粒土柱和水头等作为基本控制因... 详细信息

浑水渗流在水利工程的反滤设计、浑水浇灌、堤坝渗流控制等方面都有较大影响,目前理论多采用稳定渗流计算方法,忽略了渗流过程中粗细颗粒与水力的耦合作用。自制渗流装置,将不同控制粒径浑水、不均匀系数粗粒土柱和水头等作为基本控制因素,研究不同工况下浑水中悬浮颗粒对粗粒土土柱中的渗透特性影响;推导了变渗透系数浑水渗流计算微分方程,通过对比验证和公式修正,结果表明:粗粒土中颗粒淤积率与控制粒径C_(0.075)含量符合Boltzmann函数关系;C_(0.075)是重要的影响因子,浑水颗粒在粗粒土柱的运移、沉积和淤堵形态过程大致可分为4种形态:表层堆积淤堵形态(S型);表层-内部双重淤堵形态(S-I型);内部孔隙淤堵形态(I型);暂态孔隙淤堵形态(P型)。土柱C_(u)越大,孔隙度越小,浑水颗粒在粗粒土中运移也越困难,土柱填充性就越差;水头加剧了颗粒在土柱内部运移的速度,但也加速了其在顶部的沉积并封堵;S型时土柱0~2cm渗透系数下降速率最大,封堵时总体渗透系数最小,2cm以下相对孔隙率及随深度逐渐减小;S-I和I型土柱下部渗透系数明显滞后于上部,相对孔隙率存在临界深度(约为4~6cm);P型时土柱整体相对孔隙率基本无变化。

关键词：颗粒渗流粗粒土浑水堵塞

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宁武煤田水文地质条件探查及防治水技术

煤 2025年第1期34卷 100-103页

作者：张超山西宁武榆树坡煤业有限公司山西宁武036700

宁武煤田5号煤底板隔水层厚度较小,局部受奥灰水威胁较大,构造复杂。为探明其水文地质条件并评价其带压开采可行性及安全性,采用工程与测试相结合的方式,从隔水层厚度、岩性、力学性质、地应力等角度分析隔水层渗透性、阻水性及突水系数... 详细信息

宁武煤田5号煤底板隔水层厚度较小,局部受奥灰水威胁较大,构造复杂。为探明其水文地质条件并评价其带压开采可行性及安全性,采用工程与测试相结合的方式,从隔水层厚度、岩性、力学性质、地应力等角度分析隔水层渗透性、阻水性及突水系数,提出了防治水措施并进行了现场应用。结果表明:5号煤底板隔水层属于砂泥岩复合型,抗水压能力和隔水能力中等,突水临界指数、透水率、渗透系数、突水系数均在安全范围内,带压开采安全性较高。在5106工作面进行了针对性物探及注浆加固防治水治理,实现了工作面安全高效开采,为类似条件下煤层开采提供了指导与借鉴。

关键词：带压开采隔水层防治水措施注浆加固

Recent progress in metal-organic frameworks(Part II—material application)

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Science China Chemistry 2025年

作者： Jiandong Pang Wentao Jiang Xue-Wen zhang Hao-Long Zhou Yuxiu Sun Wei Gong Bin Wang Fuyin Ma Linwei He Long Chen Qiang Chen He-Qi Zheng Yuanjing Cui Wen-Jie Shi chao zhang Mei Wang Yue-Biao zhang Jie-Peng zhang Chongli Zhong Yong Cui Shuao Wang Jian-Rong Li Guodong Qian Tong-Bu Lu Huan Pang Xian-He Bu Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology School of Chemistry and Chemical Engineering Yangzhou University School of Materials Science and Engineering Nankai University School of Physical Science and Technology ShanghaiTech University MOE Key Laboratory of Bioinorganic and Synthetic Chemistry GBRCE for Functional Molecular Engineering School of Chemistry IGCMESun Yat-sen University Department of Chemistry Shantou University School of Chemical Engineering and Technology Tiangong University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences Soochow University College of Materials Science & Engineering Beijing University of Technology State Key Laboratory of Silicon and Advanced Semiconductor Materials Cyrus Tang Center for Sensor Materials and ApplicationsSchool of Materials Science & Engineering Zhejiang University

As a class of functional crystalline porous materials, metal-organic frameworks(MOFs) gained rapid development in the past three decades and a large number of MOFs with ordered structures, high surface areas, and functionalized channels have been investigated. MOFs and MOF-derived/composite materials show great potential in many application fields. In this review, we discussed the main applications of MOFs and MOF-derived/composite materials in small molecule storage, separation, luminescence, sensing, multitype catalysis, and energy storage. In addition, challenges and problems in the future research of MOFsrelated fields are also discussed.

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基于深度子空间学习和数据增强的滚动轴承故障诊断方法

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光电子·激光 2025年第1期36卷 69-76页

作者：张帅帅张超王肖锋天津理工大学天津市先进机电系统设计与智能控制重点实验室彼合彼方机器人(天津)有限公司天津理工大学机电工程国家级实验教学示范中心

主成分分析网络（principal component analysis network, PCANet）作为一种基于深度子空间学习框架的网络模型，在多个应用领域展现出卓越的性能。然而，在滚动轴承故障诊断方面，PCANet算法存在无法准确反映数据完整结构信息、鲁棒性... 详细信息

主成分分析网络（principal component analysis network, PCANet）作为一种基于深度子空间学习框架的网络模型，在多个应用领域展现出卓越的性能。然而，在滚动轴承故障诊断方面，PCANet算法存在无法准确反映数据完整结构信息、鲁棒性差以及泛化能力较弱等问题。本文针对这些问题，提出了一种基于PCANet算法和数据增强的滚动轴承故障诊断方法。该方法利用L2,1范数学习滚动轴承振动信号的频域稀疏结构，从而抑制噪声数据，提高模型鲁棒性。此外，通过数据增强处理，不同类别的训练样本之间的差异性也得到显著增加，从而提高了模型的泛化能力。最后，实验结果表明，该方法明显提高了PCANet模型的鲁棒性和泛化能力，能够准确识别不同类型的滚动轴承故障。

关键词：滚动轴承主成分分析网络(PCANet) 数据增强 L2,1范数故障诊断

Indecomposables with smaller cohomological length in the derived category of gentle algebras Dedicated to Professor Yingbo zhang on the Occasion of Her 70th Birthday

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Science China Mathematics 2019年第5期62卷 891-900页

作者： chao zhang Department of Mathematics Guizhou University

Bongartz(2013) and Ringel(2011) proved that there is no gaps in the sequence of lengths of indecomposable modules for the ?nite-dimensional algebras over algebraically closed ?elds. The present paper mainly studies this "no gaps" theorem as to cohomological length for the bounded derived category Db(A) of a gentle algebra A: if there is an indecomposable object in D^b(A) of cohomological length l > 1, then there exists an indecomposable with cohomological length l-1.

关键词： cohomological length generalized string(band) derived discrete algebras

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The Representation Type of Repetitive Algebras over the Real Number Field

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Algebra Colloquium 2023年第2期30卷 305-314页

作者： Mengdie zhang chao zhang Department of Mathematics School of Mathematics and Statistics Guizhou UniversityGuiyang 550025China

Let A be a finite-dimensional algebra over the real number *** prove that the repetitive algebra A admits the dichotomy property of representation type,i.e.,A is either of discrete representation type or of strongly u... 详细信息

关键词： C-dichotomic algebra derived-discrete algebra finite separable extension strongly unbounded type

Oxygen vacancy engineering on cerium oxide nanowires for room-temperature linalool detection in rice aging

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Journal of Advanced Ceramics 2022年第10期11卷 1559-1570页

作者： Jinyong XU chao zhang College of Mechanical Engineering Yangzhou UniversityYangzhou 225127China

It is a huge challenge for metal oxide semiconductor gas sensors to inspect volatile organic compounds(VOCs)at room temperature(RT).Herein,the effective utilization of cerium oxide(CeO_(2))nanowires for RT detection of VOCs was realized via regulating its surface chemical *** vacancy engineering on CeO_(2) nanowires,synthesized via hydrothermal method,can be manipulated by annealing under various controlled *** sample annealed under 5%H_(2)+95%Ar condition exhibited outstanding RT sensing properties,displaying a high response of 16.7 towards 20 ppm linalool,a fast response and recovery time(16 and 121 s,respectively),and a low detection of limit of 0.54 *** enhanced sensing performance could be ascribed for the synergistic effects of its nanowire morphology,the large specific surface area(83.95 m^(2)/g),and the formation of extensive oxygen vacancy accompanied by an increase in Ce^(3+).Additionally,the practicability of the sensor was verified via two varieties of rice(Indica and Japonica rice)stored in various periods(1,3,5,7,15,and 30 d).The experimental results revealed that the sensor was able to distinguish Indica rice from Japonica ***,the as-developed sensor delivers a strategic material to develop high-performance RT electronic nose equipment for monitoring rice quality.

关键词： erium oxide(CeO_(2)) nanowire oxygen vacancy linalool gas sensor

ForkXplorer:an approach of fork summary generation

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Frontiers of Computer Science 2022年第2期16卷 1-15页

作者： zhang zhang Xinjun MAO chao zhang Yao LU Key Laboratory of Software Engineering for Complex Systems College of ComputerNational University of Defense TechnologyChangsha 410073China

Pull-based development has become an important paradigm for distributed software *** this model,each developer independently works on a copied repository(i.e.,a fork)from the central *** is essential for developers to maintain awareness of the state of other forks to improve collaboration *** this paper,we propose a method to automatically generate a summary of a *** first use the random forest method to generate the label of a fork,i.e.,feature implementation or a bug *** on the information of the fork-related commits,we then use the TextRank algorithm to generate detailed activity information of the ***,we apply a set of rules to integrate all related information to construct a complete fork *** validate the effectiveness of our method,we conduct 30 groups of manual experiment and 77 groups of case studies on *** propose Fea_(avg)to evaluate the performance of Fea_(avg)the generated fork summary,considering the content accuracy,content integrity,sentence fluency,and label extraction *** results show that the average of of the fork summary generated by this method is *** than 63%of project maintainers and the contributors believe that the fork summary can improve development efficiency.

关键词： open source software pull-based development fork summary distributed cooperative development

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