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Light People:*** Mazur speaks about ultrafast optics and education

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Light(Science & Applications) 2024年第3期13卷 402-406页

作者： Chenzi guo Yang Li Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina State Key Laboratory of Precision Measurement Technology and Instrument Department of Precision InstrumentTsinghua UniversityBeijingChina

*** Mazur is a great influencer over and beyond the optics *** a physicist,he is a pioneer of ultrafast optics and was one of the inventors of colliding-pulse mode-locked *** an educator,he not only gave talks to thousands,but also revolutionized teaching with his globally renowned methodology“Peer Instruction”.As a leader and entrepreneur,he co-founded several companies and was President of Optica(formerly the Optical Society)and currently is the Chair of the Optica ***,Light:Science&Applications talked with *** Mazur about his opinions on research,education and *** full interview video can be found in the Supplementary File.

关键词： optics education companies

A unified stochastic damage model for concrete based on multi-scale energy dissipation analysis

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Science China(Technological Sciences) 2024年第3期67卷 863-877页

作者： guo ChengGong LI Jie College of Civil Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Shanghai 200092China

This work proposes a unified damage model for concrete within the framework of stochastic damage mechanics. Based on the micro-meso stochastic fracture model(MMSF), the nonlinear energy dissipation process of the microspring from nanoscale to microscale is investigated. In nanoscale, the rate process theory is adopted to describe the crack growth rate;therefore, the corresponding energy dissipation caused by a representative crack propagation can be obtained. The scale gap from nanoscale to microscale is bridged by a crack hierarchy model. Thus, the total energy dissipated by all cracks from the nanoscale to the microscale is gained. It is found that the fracture strain of the microspring can be derived from the above multi-scale energy dissipation analysis. When energy dissipation is regarded as some microdamage to the microspring, the constitutive law of the microspring is no longer linearly elastic, as previously assumed. By changing the expression of the damage evolution law from fracture strain to energy dissipation threshold, the new damage evolution model is derived. The proposed model can not only replicate the original static model but also extend to cases of rate dependence. By deriving the fracture strain under different strain rates, the rate sensitivity of concrete materials can be reflected. The model parameters can be conveniently obtained by identifying them with experimental data. Finally, several numerical examples are presented to verify the proposed model.

关键词： concrete damage model stochastic damage rate dependent energy dissipation

Localizing vitamin-C through nanoconfinement enables high-rate CO_(2) electrolysis to ethylene

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Science China Materials 2024年第3期67卷 1006-1008页

作者： Zhengyi Qian Shaojun guo School of Materials Science and Engineering Peking UniversityBeijing 100871China

The electrosynthesis of value-added fuels and chemicals from carbon dioxide reduction reaction(CO_(2)RR)is a promising approach for realizing the objectives of carbon neutrality[1].Nevertheless,the current production of desirable multicarbon(C_(2+))chemicals,such as ethylene(C_(2)H_(4)),still encounters challenges related to low selectivity,low current density,and the requirement for high-purity feeding gas[2].

关键词： enable purity dioxide

A short review of antibacterial Cu-bearing stainless steel:antibacterial mechanisms,corrosion resistance,and novel preparation techniques

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Journal of Iron and Steel Research International 2024年第1期31卷 24-45页

作者： Shuai Liu Han-jie guo School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology BeijingBeijing100083China

Cu-bearing stainless steel is widely used in the fields of food,medical and household sanitary equipment because of its surface finish and corrosion ***,the growth of bacteria on stainless steel leads to the formation of biofilms,which causes ***,the antibacterial property of stainless steel is a worthy research *** of breakthroughs in the field of corrosion resistance and antimicrobial properties are still ***,due to the scarcity of publications on the antibacterial mechanisms and processing methods of antibacterial Cu-bearing stainless steel,we review the current state of relevant research and *** toxicity of Cu,corrosion resistance mechanism of stainless steel,and antibacterial mechanism and preparation method of antibacterial stainless steel are *** addition,alloying,surface modification and other methods are found to have limitations in balancing the toxicity and antibacterial properties of copper and the relationship between the antibacterial properties and corrosion resistance of Cu-bearing stainless steel.A new preparation method of antibacterial stainless steel associated with selective laser melting(SLM)is *** is becoming a powerful additive manufacturing technology that can be used to manufacture customized and complex *** research status of SLM applied in antibacterial stainless steel preparation is ***,the future research direction of Cu-bearing antibacterial stainless steel is discussed.

关键词： Cu-bearing stainless steel Antibacterial Processing Additive manufacturing Corrosion resistance

Privacy-Preserving Consensus-Based Distributed Economic Dispatch of Smart Grids via State Decomposition

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1250-1261页

作者： Wei Chen guo-Ping Liu The authors are with the Center for Control Science and Technology Southern University of Science and TechnologyShenzhen 518055China

This paper studies the privacy-preserving distributed economic dispatch(DED)problem of smart *** autonomous consensus-based algorithm is developed via local data exchange with neighboring nodes,which covers both the islanded mode and the grid-connected mode of smart *** prevent power-sensitive information from being disclosed,a privacy-preserving mechanism is integrated into the proposed DED algorithm by randomly decomposing the state into two parts,where only partial data is *** objective is to develop a privacy-preserving DED algorithm to achieve optimal power dispatch with the lowest generation cost under physical constraints while preventing sensitive information from being *** this end,a comprehensive analysis framework is established to ensure that the proposed algorithm can converge to the optimal solution of the concerned optimization problem by means of the consensus theory and the eigenvalue perturbation *** particular,the proposed autonomous algorithm can achieve a smooth transition between the islanded mode and the grid-connected ***,rigorous analysis is given to show privacy-preserving performance against internal and external ***,case studies illustrate the feasibility and validity of the developed algorithm.

关键词： preserving autonomous mode

Improving mathematical model of burden distribution and correcting chute angle to cope with fluctuation of stock line

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Journal of Iron and Steel Research International 2024年第2期31卷 342-356页

作者： Jian-sheng Chen Wen-guo Liu Hao guo Wang Ding Qing-guo Xue Jing-song Wang Hai-bin Zuo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China MCC Capital Engineering&Research Incorporation Limited Beijing100176China Hunan Valin Xiangtan Iron and Steel Co. Ltd.Xiangtan411101HunanChina

Accurate evaluations of the burden distribution are of critical importance to stabilize the operation of blast *** mathematical model and discrete element method(DEM)are two attractive methods for predicting burden *** on DEM,the initial velocities of the pellet,sinter,and coke were calculated,and the velocity attenuations of the above three particles between the burden and the chute were *** initial velocity and velocity attenuation were applied to a mathematical model for improving the ***,based on the improved model,a scheme for rectifying the chute angles was proposed to address the fluctuation of the stock line and maintain a stable burden *** validity of the scheme was confirmed via a stable burden distribution under different stock *** mathematical model has been successfully applied to evaluate the online burden distribution and cope with the fluctuation of the stock line.

关键词： Burden distribution Mathematical model Discrete element method Velocity attenuation Stock line fluctuation

Predicting torsional capacity of reinforced concrete members by data-driven machine learning models

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 444-460页

作者： Shenggang CHEN Congcong CHEN Shengyuan LI Junying guo Quanquan guo Chaolai LI School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 211116China Jiangsu Key Laboratory Environmental Impact and Structural Safety in Engineering China University of Mining and TechnologyXuzhou 211116China China Nuclear Power Design Co.Ltd. Shenzhen 518031China School of transportation and science engineering Beihang UniversityBeijing 100191China China Construction First Group Corporation Limited Beijing 100161China

Due to the complicated three-dimensional behaviors and testing limitations of reinforced concrete(RC)members in torsion,torsional mechanism exploration and torsional performance prediction have always been *** the present paper,several machine learning models were applied to predict the torsional capacity of RC *** results of a total of 287 torsional specimens were collected through an overall literature *** of extreme gradient boosting machine(XGBM),random forest regression,back propagation artificial neural network and support vector machine,were trained and tested by 10-fold cross-validation *** performances of proposed machine learning models were evaluated and compared,both with each other and with the calculated results of existing design codes,i.e.,GB 50010,ACI 318-19,and Eurocode *** results demonstrated that better predictive performance was achieved by machine learning models,whereas GB 50010 slightly overestimated the torsional capacity,and ACI 318-19 and Eurocode 2 underestimated it,especially in the case of ACI *** XGBM model gave the most favorable predictions with R^(2)=0.999,RMSE=1.386,MAE=0.86,andλ=***,strength of concrete was the most sensitive input parameters affecting the reliability of the predictive model,followed by transverse-to-longitudinal reinforcement ratio and total reinforcement ratio.

关键词： RC members torsional capacity machine learning models design codes

Improving benzene catalytic oxidation on Ag/Co_(3)O_(4) by regulating the chemical states of Co and Ag

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Journal of Environmental Sciences 2024年第9期143卷 201-212页

作者： Hao guo Tao guo Mengqi Zhao Yaxin Zhang Wenfeng Shangguan Yinnian Liao State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources Xinjiang UniversityXinjiang 830017China Xinjiang Key Laboratory of Coal Clean Conversion&Chemical Engineering Process Xinjiang UniversityXinjiang 830017China School of Chemical Engineering and Technology Xinjiang UniversityXinjiang 830017China Research Center for Combustion and Environmental Technology Shanghai Jiao Tong UniversityShanghai 200240China School of Applied Chemistry and Materials Zhuhai College of Science and TechnologyGuangdong 519041China

Silver(9 wt.%)was loaded on Co_(3)O_(4)-nanofiber using reduction and impregnation methods,*** to the stronger electronegativity of silver,the ratios of surface Co^(3+)/Co^(2+) on Ag/Co_(3)O_(4) were higher than on Co_(3)O_(4),which further led to more adsorbed oxygen species as a result of the charge ***,the introducing of silver also obviously improved the reducibility of Co_(3)O_(4).Hence the Ag/Co_(3)O_(4) showed better catalytic performance than Co_(3)O_(4) in benzene *** with the Ag/Co_(3)O_(4) synthesized via impregnation method,the one prepared using reduction method(named as Ag Co-R)exhibited higher contents of surface Co^(3+) and adsorbed oxygen species,stronger reducibility,as well as more active surface lattice oxygen ***,Ag Co-R showed lowest T_(90) value of 183℃,admirable catalytic stability,largest normalized reaction rate of1.36×10^(-4)mol/(h·m^(2))(150℃),and lowest apparent activation energy(E_(a))of 63.2 kJ/*** analyzing of in-situ DRIFTS indicated benzene molecules were successively oxidized to phenol,o-benzoquinone,small molecular intermediates,and finally to CO_(2) and water on the surface of Ag *** last,potential reaction pathways including five detailed steps were proposed.

关键词： Reduction method Co_(3)O_(4)-supported Ag catalyst,VOCs Benzene oxidation Reaction mechanism

Saddlepoint Approximation Method in Reliability Analysis:A Review

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2329-2359页

作者： Debiao Meng Yipeng guo Yihe Xu Shiyuan Yang Yongqiang guo Lidong Pan Xinkai guo School ofMechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu611731China Institute of Electronic and Information Engineering of UESTC in Guangdong Dongguan523808China Glasgow College University of Electronic Science and Technology of ChinaChengdu611731China Beijing Research Institute of Mechanical&Electrical Technology Ltd.Beijing100083China

The escalating need for reliability analysis(RA)and reliability-based design optimization(RBDO)within engineering challenges has prompted the advancement of saddlepoint approximationmethods(SAM)tailored for such *** article offers a detailed overview of the general SAM and summarizes the method characteristics ***,recent enhancements in the SAM theoretical framework are ***,the mean value first-order saddlepoint approximation(MVFOSA)bears resemblance to the conceptual framework of the mean value second-order saddlepoint approximation(MVSOSA);the latter serves as an auxiliary approach to the *** distinction is rooted in the varying expansion orders of the performance function as implemented through the Taylor *** the saddlepoint approximation and third-moment(SATM)and saddlepoint approximation and fourth-moment(SAFM)strategies model the cumulant generating function(CGF)by leveraging the initial random moments of the *** their optimal application domains diverge,each method consistently ensures superior relative precision,enhanced efficiency,and sustained *** method elucidated is exemplified through pertinent RA or RBDO *** juxtaposing them against alternative strategies,the efficacy of these methods becomes *** outcomes proffered are subsequently employed as a foundation for contemplating prospective theoretical and practical research endeavors concerning *** main purpose and value of this article is to review the SAM and reliability-related issues,which can provide some reference and inspiration for future research scholars in this field.

关键词： Reliability analysis reliability-based design optimization saddlepoint approximation