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Chinese Chemical Letters 2024年第1期35卷 418-423页

作者： Yan Gong Yu ding Qi Tang Fei Lian Chun Bai Ruiyi xie Haijiao xie Xu Zhao School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300401China Hangzhou Yanqu Information Technology Co. Ltd.Hangzhou 310003China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Collapse

Photocatalytic activation of peroxymonosulfate (PMS) has garnered a lot of interest in the field of wastewater treatment. Herein, a plasmonic Ag nanoparticles decorated MIL-101(Fe) hybrid was synthesized through a photodeposition process. Upon light irradiation, the Ag/MIL-101(Fe) exhibit reinforced photocatalytic activities for elimination of bisphenol A (BPA) with PMS. The optimized 2.0% Ag/MIL-101(Fe) composite presented the highest photocatalytic activity with kinetic constant k of 0.102 min-1, which was about 10-fold of the pristine MIL-101(Fe). Loading of plasmonic Ag into MIL-101(Fe) boosts photoinduced carrier separation and accelerates PMS activation to generate strong oxidative radicals. Photoelectrochemical tests and multiple spectroscopic studies confirmed the promoted charge carrier separation and transfer capability of Ag/MIL-101(Fe). Combining the results of radical trapping experiments and electron spin resonance (ESR), the formed SO4·-, ·OH, ·O2- and 1O2 had a significant role in the photocatalytic process. According to intermediate study, the degradation pathway was studied, and the possible mechanism was proposed.

关键词： Photocatalysis MOF Peroxymonosulfate Plasmonic Ag BPA

One more step to realistic CO_(2) reduction reactions——geometric structures evolutions at gas-solid interface

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Rare Metals 2024年第2期43卷 849-852页

作者： Ya-Qiang xie Xin Yu Ting Wang College of the Environment and Ecology Xiamen UniversityXiamen361102China

A rational design of copper(Cu)nanocatalyst is critical to the efficient carbon dioxide(CO_(2))conversion toward C1/C2 chemical ***,the lack of actual information on the vicinal Cu interfaces hinders the intrinsic activitystructure correlation *** with atomic-scale in situ characterizations(AP-STM and synchrotron-based AP-XPS),Park and co-workers study and identify the adsorbate-driven morphological evolution of Cu nanoclusters on the Cu(997)surface,providing real-space evidence for the critical role of vicinal structures on Cu *** observed surface roughening trends caused by dissociated atomic oxygen and CO adsorbates subsequently affect the result of successive catalytic reactions to produce critical intermediates,such as carbonate and formate,during the CO_(2)reduction reaction.

关键词： reaction critical rational

In-situ powder mixing for laser-based directed energy deposition of functionally graded materials

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Advances in Manufacturing 2024年第1期12卷 150-166页

作者： Ji-Peng Chen Shou-Chun xie He Huang School of Mechanical and Electronic Engineering Nanjing Forestry UniversityNanjing210037People’s Republic of China Nanjing Huirui Photoelectric Technology Co. LtdNanjing211121People’s Republic of China

The mixing of powders is a highly relevant field under additive manufacturing,however,it has attracted limited interest to *** in-situ mixing of various powders remains a significant *** paper proposes a new method utilizing a static mixer for the in-situ mixing of multiple powders through the laser-based directed energy deposition(DED)of functionally graded ***,a powder-mixing experimental platform was established;WC and 316L powders were selected for the mixing ***,scanning electron microscopy,energy dispersive spectroscopy,and image processing were used to visually evaluate the homogeneity and proportion of the in-situ mixed ***,powder-mixing simulations were conducted to determine the powder-mixing *** the simulations,a powder carrier gas flow field and particle mixing were ***,a WC/316L metal matrix composite sample was produced using laser-based DED to verify the application potential of the static *** was found that the static mixer could adjust the powder ratio online,and a response time of 1–2 s should be considered when adjusting the ratio of the mixed powder.A feasible approach for in-situ powder mixing for laser-based DED was demonstrated and investigated,creating the basis for functionally graded materials.

关键词： Laser Deposition Static mixer Powder mixing Functionally graded materials

QoE oriented intelligent online learning evaluation technology in B5G scenario

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Digital Communications and Networks 2024年第1期10卷 7-15页

作者： Mingzi Chen Xin Wei Peizhong xie Zhe Zhang School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing210003China Institute of Higher Education Nanjing University of Posts and TelecommunicationsNanjing210003China

Students'demand for online learning has exploded during the post-COvID-19 pandemic ***,due to their poor learning experience,students'dropout rate and learning performance of online learning are not always *** technical advantages of Beyond Fifth Generation(B5G)can guarantee a good multimedia Quality of Experience(QoE).As a special case of multimedia services,online learning takes into account both the usability of the service and the cognitive development of the *** that affect the Quality of Online Learning Experience(OL-QoE)become more *** get over this dilemma,we propose a systematic scheme by integrating big data,Machine Learning(ML)technologies,and educational psychology ***,we first formulate a general definition of OL-QoE by data analysis and experimental *** formula considers both the subjective and objective factors(i.e.,video watching ratio and test scores)that most affect ***,we induce an extended layer to the classic Broad Learning System(BLS)to construct an Extended Broad Learning System(EBLS)for the students'OL-QoE *** the extended layer can increase the width of the BLS model and reduce the redundant nodes of BLS,the proposed EBLS can achieve a trade-off between the prediction accuracy and computation ***,we provide a series of early intervention suggestions for different types of students according to their predicted OL-QoE *** timely interventions,their OL-QoE and learning performance can be *** results verify the effectiveness oftheproposed scheme.

关键词： B5G Online learning Quality of experience

Recent progress in visualization and digitization of coherent transformation structures and application in high-strength steel

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1298-1310页

作者： Xuelin Wang Zhenjia xie Xiucheng Li Chengjia Shang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Yangjiang Branch Guangdong Laboratory for Materials Science and Technology(Yangjiang Advanced Alloys Laboratory)Yangjiang 529500China

High-strength steels are mainly composed of medium-or low-temperature microstructures,such as bainite or martensite,with coherent transformation *** type of microstructure has a high density of dislocations and fine crystallographic structural units,which ease the coordinated matching of high strength,toughness,and ***,given its excellent welding perform-ance,high-strength steel has been widely used in major engineering constructions,such as pipelines,ships,and ***,visual-ization and digitization of the effective units of these coherent transformation structures using traditional methods(optical microscopy and scanning electron microscopy)is difficult due to their complex ***,the establishment of quantitative relationships with macroscopic mechanical properties and key process parameters presents additional *** article reviews the latest progress in microstructural visualization and digitization of high-strength steel,with a focus on the application of crystallographic methods in the development of high-strength steel plates and *** obtained the crystallographic data(Euler angle)of the transformed microstruc-tures through electron back-scattering diffraction and combined them with the calculation of inverse transformation from bainite or martensite to austenite to determine the reconstruction of high-temperature parent austenite and orientation relationship(OR)during con-tinuous cooling ***,visualization of crystallographic packets,blocks,and variants based on actual OR and digit-ization of various grain boundaries can be effectively completed to establish quantitative relationships with alloy composition and key process parameters,thereby providing reverse design guidance for the development of high-strength steel.

关键词： high-strength steel microstructure visualization digitization quantification mechanical properties

A brief review on the recent development of phonon engineering and manipulation at nanoscales

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International Journal of Extreme Manufacturing 2024年第1期6卷 177-206页

作者： Siqi xie Hongxin Zhu Xing Zhang Haidong Wang Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084People’s Republic of China

Phonons are the quantum mechanical descriptions of vibrational modes that manifest themselves in many physical properties of condensed matter systems. As the size of electronic devices continues to decrease below mean free paths of acoustic phonons, the engineering of phonon spectra at the nanoscale becomes an important topic. Phonon manipulation allows for active control and management of heat fow, enabling functions such as regulated heat transport. At the same time, phonon transmission, as a novel signal transmission method, holds great potential to revolutionize modern industry like microelectronics technology, and boasts wide-ranging applications. Unlike fermions such as electrons, polarity regulation is difficult to act on phonons as bosons, making the development of effective phonon modulation methods a daunting *** work reviews the development of phonon engineering and strategies of phonon manipulation at different scales, reports the latest research progress of nanophononic devices such as thermal rectifiers, thermal transistors, thermal memories, and thermoelectric devices,and analyzes the phonon transport mechanisms involved. Lastly, we survey feasible perspectives and research directions of phonon engineering. Thermoelectric analogies, external field regulation, and acousto-optic co-optimization are expected to become future research hotspots.

关键词： phonon engineering phononic device nanoscale

Tailoring MXene Thickness and Functionalization for Enhanced Room‑Temperature Trace NO_(2) Sensing

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Nano-Micro Letters 2024年第5期16卷 71-86页

作者： Muhammad Hilal Woochul Yang Yongha Hwang Wanfeng xie Department of Physics Dongguk UniversitySeoul 04620Republic of Korea Department of Control and Instrumentation Engineering Korea UniversitySejong 30019Republic of Korea School of Electronics&Information University‑Industry Joint Center for Ocean Observation and Broadband CommunicationQingdao UniversityQingdao 266071China

In this study,precise control over the thickness and termination of Ti3C2TX MXene flakes is achieved to enhance their electrical properties,environmental stability,and gas-sensing *** a hybrid method involving high-pressure processing,stirring,and immiscible solutions,sub-100 nm MXene flake thickness is achieved within the MXene film on the *** control is achieved by defunctionalizing MXene at 650℃ under vacuum and H2 gas in a CVD furnace,followed by refunctionalization with iodine and bromine vaporization from a bubbler attached to the ***,the introduction of iodine,which has a larger atomic size,lower electronegativity,reduce shielding effect,and lower hydrophilicity(contact angle:99°),profoundly affecting *** improves the surface area(36.2 cm^(2) g^(-1)),oxidation stability in aqueous/ambient environments(21 days/80 days),and film conductivity(749 S m^(-1)).Additionally,it significantly enhances the gas-sensing performance,including the sensitivity(0.1119Ωppm^(-1)),response(0.2% and 23%to 50 ppb and 200 ppm NO_(2)),and response/recovery times(90/100 s).The reduced shielding effect of the–I-terminals and the metallic characteristics of MXene enhance the selectivity of I-MXene toward *** approach paves the way for the development of stable and high-performance gas-sensing two-dimensional materials with promising prospects for future studies.

关键词： Controlled MXene thickness Gaseous functionalization approach Lower electronegativity functional groups Enhanced MXene stability Trace NO_(2)sensing

Customer Joining Behavior and Regulation Strategy in Visible Multi-Server Queues with Synchronous Vacations of Partial Servers

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Journal of Systems Science & Complexity 2024年第3期37卷 1209-1232页

作者： SUN Wei WANG Hao xie Xumeng LI Shiyong School of Economics and Management Yanshan UniversityQinhuangdao 066004China

This paper studies customer joining behavior and system regulation strategy in nonexhaustive visible M/M/m queues with synchronous vacations of a part of the *** this part of the servers are idle,they take multiple vacations simultaneously(vacation period).Until there are customers waiting in the queue,they are reactivated and all servers are busy or idle(busy period).The authors call this part of the servers as“partial servers”.In view of the fully visible queue and the almost visible queue,the authors obtain customers’equilibrium joining threshold strategies and their socially optimal joining threshold strategies,respectively,and observe that customer joining behavior in equilibrium generally makes the system overcrowded,which makes the equilibrium social welfare lower than the optimal social *** regulation,interestingly,for optimizing social welfare,the system manager hopes not only customers arriving in vacation period pay attention to the number of partial servers,but also customers arriving in busy period should care about it rather than ***,arranging more servers for vacation does not necessarily lead to the decrease of social welfare on condition that the number of partial servers is close to *** for the information advantage of the fully visible case,it is not obvious for increasing social welfare and even unfavorable to servers’profit unless the number of partial servers is big ***,given the different composition of social welfare,there exists the optimal number of partial servers and the optimal arrival rate of customers for maximizing social welfare.

关键词： Customer behavior non-exhaustive service partial servers regulation strategy synchronous vacations visible queue

Investigation on the influence of vortex generator on particle resuspension

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Particuology 2024年第3期86卷 126-136页

作者： Dongchi Yu Jun-Li Lin Jin-Han xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

Event-triggered finite-time command-filtered tracking control for nonlinear time-delay cyber physical systems against cyber attacks

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 225-236页

作者： Yajing MA Yuan WANG Zhanjie LI Xiangpeng xie School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China Institute of Advanced Technology for Carbon NeutralityNanjing University of Posts and TelecommunicationsNanjing210023China

This article addresses the secure finite-time tracking problem via event-triggered command-filtered control for nonlinear time-delay cyber physical systems(CPSs)subject to cyber *** the attack circumstance,the output and state information of CPSs is unavailable for the feedback design,and the classical coordinate conversion of the iterative process is incompetent in relation to the tracking *** solve this,a new coordinate conversion is proposed by considering the attack gains and the reference signal *** employing the transformed variables,a modified fractional-order command-filtered signal is incorporated to overcome the complexity explosion issue,and the Nussbaum function is used to tackle the varying attack *** systematically constructing the Lyapunov-Krasovskii functional,an adaptive event-triggered mechanism is presented in detail,with which the communication resources are greatly saved,and the finite-time tracking of CPSs under cyber attacks is ***,an example demonstrates the effectiveness.

关键词： Cyber physical systems Finite-time tracking Event-triggered Command-filtered control Attacks