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Online estimation and characteristic analysis of double nugget diameters during aluminum/steel resistance spot welding process

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Journal of Iron and Steel Research International 2024年第8期31卷 2053-2067页

作者： Kang Zhou wen-xiao Yu Bao-kai Ren Gang Wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

Online estimation of the double nugget diameters was performed by means of a back propagation neural *** double nugget diameters were obtained using actual welding experiment and numerical simulation,according to different characteristics of aluminum nugget and steel *** input of the neural network was some key characteristic parameters extracted from dynamic power signal,which were peak point,knee point and their variation rate over time,as well as heat energy delivered into the welding *** architecture of the neural network was confirmed by confirming the number of neurons in hidden layer through a series of *** key parameters of the neural network were obtained by means of training 81 arrays of data ***,the neural network was used to test the remaining 20 arrays of verifying data set,and the results showed that both of the mean errors for the two nugget diameters were below 3%.In addition,corresponding analyses showed that the accuracy of two nugget diameters was higher than that of tensile-shear strength.

关键词： Resistance spot welding Aluminum Steel Double nugget Dynamic power signal.Neural network

Effect of Artificial Electric Field Surface by Wave-Driven Triboelectricity on Anti-Bioadhesion for Riser Protection

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China Ocean Engineering 2024年第3期38卷 483-490页

作者： YI Peng QIU Hong-yuan LI Yong CAI Bao-ping Javad MOSTAGHIMI ZHANGwen-jie xiao wen-sheng College of Mechanical and Electrical Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Equipment Technology Co. Ltd.Tianjin 300450China Department of Mechanical&Industrial Engineering University of TorontoToronto ONM5S3G8Canada

Biofouling has been a persistent problem in marine riser system, resulting in energy waste and equipment damage. Inthis study, a kind of water wave-driven contact-mode flexible triboelectric nanogeneration has been prepared byusing graphene-doped PDMS as dielectric friction material. When the graphene content is 2%, the average outputvoltage can reach 46 V under the contact frequency 10 Hz. The flexible triboelectric nanogeneration encapsulationmodule is impinged by water waves to generate alternating microelectric field on the riser surface and destroy theadhesion conditions of microorganisms during the biofilm stage. In the biofouling experiments at different stages, thebiofouling area of the platymonas subcordiformis has been reduced by 53%, 62% and 61%. It provides a new ideafor effective treatment of biofouling of mussels, oysters and barnacles attached to risers.

关键词： wave-drive triboelectric nanogeneration alternating microelectric field anti-biofouling

Dynamic steric confinement effect expands the frontier of Cu-catalyzed asymmetric propargylic aminations

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Science China Chemistry 2024年第10期67卷 3181-3183页

作者： Peng Chen Mao-Mao Zhang wen-Jing xiao Liang-Qiu Lu Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal University Wuhan Institute of Photochemistry and Technology State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics (LICP)Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

Chiral α-tertiary amines and related azacycles are commonly found in many natural products, pharmaceuticals and agrochemicals [1]. Copper-catalyzed asymmetric propargylic amination(APA) reactions have been established as a reliable method to access enantio-enriched propargylic amines,largely due to the seminal contribution of Nishibayashi et al.[2] and van Maarseveen et al. [3] in 2008.

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Visible-Light-Driven Four-Component Radical Relay Aminocarbonylation of Unactivated Alkenes

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Chinese Journal of Chemistry 2024年第9期42卷 990-996页

作者： Bin Lu Feng-Shuo Bao Zi-Wei He wen-Jing xiao Jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction College of ChemistryCentralChina Normal University152 Luoyu RoadWuhanHubei 430079China Wuhan Institute of Photochemistry and Technology 7North Bingang RoadWuhanHubei 430083China Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal UniversityGanzhouJiangxi 341000China

Catalytic four-component radical carbonylation of unactivated alkenes has recently been recognized as a robust protocol for rapid construction of various structurally diverse carbonyl *** the significance of fluorine-containing groups,this reaction class has been extensively applied to assembly of a variety of perfluoroalkyl carboxylic acid derivatives by transition metal ***,we report a visible-light-driven radical relay 1,2-perfluoroalkylation aminocarbonylation of unactivated alkenes using CO gas as carbonyl source and 4CzIPN as organic photocatalyst.A wide range of alkenes and amines were well tolerated,providing the valuableβ-perfluoroalkylated amides with generally good yields and high chemoselectivity.

关键词： Visible light Photoredox catalysis Radical aminocarbonylation Multicomponent reaction Carbon monoxide Unactivated alkenes AmidesIReactionmechanisms

Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation

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Chinese Journal of Chemical Engineering 2024年第1期65卷 75-84页

作者： wen xiao Peng Dong Chan Wang Jingdong Xu Tiesen Li Haibo Zhu Tinghai Wang Renwei Xu Yuanyuan Yue National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou 362801China Sinochem Quanzhou Energy Technology Co. Ltd.Quanzhou 362000China

Zeolite catalysts have found extensive applications in the synthesis of various fine ***,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic ***,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the Knoevenagel condensation reaction for producing the useful fine chemical *** synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or *** characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX *** mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized *** synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing.

关键词： Hierarchical NaX zeolite Template-free synthesis Natural kaolinite Knoevenagel condensation

Asymmetric radical allylation of β-keto esters with vinyl cyclopropanes by dual photoredox/nickel catalysis

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Science China Chemistry 2024年

作者： wen-Yuan Qu Xue-Song Zhou wen-Jing xiao Jia-Rong Chen Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of Chemistry Central China Normal University Wuhan Institute of Photochemistry and Technology Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal University

Radical-involved allylation reactions have emerged as a powerful platform for construction of carbon-carbon and carbonheteroatom bonds, facilitating the strategic incorporation of diverse allyl moieties. Nevertheless, this burgeoning field still faces ongoing challenges, including limitations of radical precursors and coupling partners, and difficulties in achieving enantiocontrol. Herein, we report for the first time a highly enantioselective radical allylation involving β-keto esters with vinyl cyclopropanes utilizing a synergistic dual photoredox/nickel catalysis under visible light irradiation. The mild and redox-neutral catalytic protocol demonstrates an extensive substrate compatibility and good functional tolerance, providing access to enantioenriched β-keto esters featuring quaternary α-stereocenter with good yields and high enantioselectivities. Preliminary mechanistic studies have uncovered that the success of the reaction hinges on the dual roles of nickel catalyst, including in situ formation of photoredox sensitive substrate/Ni complex and the ensuing asymmetric radical addition step.

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Exploring new physics in ultra-peripheral heavy ion collisions

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 22-22页

作者： Bo-wen xiao School of Science and Engineering The Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Shenzhen 518172China

Ultra-peripheral heavy ion collisions involve interactions between heavy ions,such as gold or lead nuclei,at high energies,where the impact parameter is large enough to prevent strong interaction between *** these collisions,the ions pass close enough for their electromagnetic fields to interact,leading to phenomena like photonuclear and two-photon interactions.

关键词： interaction parameter enough

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A Descriptive Translation Study of Chinese Translation of French Musical Roméo et Juliette

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Journal of Literature and Art Studies 2024年第6期14卷 462-467页

作者： SHI xiao-wen School of Translation Studies Shandong UniversityWeihaiChina

This paper presents a Descriptive Translation Study(DTS)analysis of the Chinese translation of the French musical adaptation of Romeo and Juliet,titled Roméo et Juliette:de la Haineàl’*** and Juliet,a timeless play by Shakespeare,has captivated audiences since its premiere in 1597 and has been adapted into various forms,including stage productions,films,musicals,and *** focus of this study is to analyze the Chinese translation of the French musical adaptation from a DTS *** is an approach that aims to understand the translation process and its reception in the target *** examining language choices,cultural references,and adaptation strategies,this study seeks to shed light on how the Chinese translation of the French musical functions within the target culture and influences the reception and interpretation of the source *** analysis is expected to gain insights into the challenges and strategies employed in translating a musical adaptation of Romeo and Juliet into *** findings of this study will contribute to the field of translation studies and provide a deeper understanding of the complexities involved in the translation of musical works.

关键词： Descriptive Translation Study(DTS) Chinese translation musical adaption of classics Romeo and Juliet reception and interpretation

Risk factors for renal outcomes in children with antineutrophil cytoplasmic antibody-associated vasculitis:a nationwide retrospective study in China

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World Journal of Pediatrics 2024年第5期20卷 506-516页

作者： Li-wen Tan Jun-Li Wan Chun-Hua Zhu Hong Xu Zheng-Kun Xia Li-Zhi Chen xiao-Chuan Wu Fang Wang xiao-Rong Liu Cheng-Guang Zhao xiao-Zhong Li Jian-Hua Mao xiao-wen Wang wen-Yan Huang Yu-Hong Li Jian-Jiang Zhang Shi-Pin Feng Jun Yang Jiao-Jiao Liu Chun-Lin Gao Li-Ping Rong Lan-Jun Shuai Ke Xu He-Jia Zhang Qiu Li Ai-Hua Zhang Mo Wang Department of Nephrology Children’s Hospital of Chongqing Medical UniversityZhongshan 2nd Rd.136Chongqing400014China Ministry of Education Key Laboratory of Child Development and Disorders National Clinical Research Center for Child Health and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChildren’s Hospital of Chongqing Medical UniversityChongqingChina Chongqing Key Laboratory of Pediatrics Children’s Hospital of Chongqing Medical UniversityChongqingChina Department of Nephrology Children’s Hospital of Nanjing Medical University72 Guangzhou RoadNanjing210008China Department of Nephrology Children’s Hospital of Fudan UniversityNational Paediatric Medical Center of ChinaShanghaiChina Department of Pediatrics Jinling HospitalNanjing Medical UniversityNanjingChina Department of Pediatrics Jinling HospitalThe First School of Clinical MedicineSouthern Medical UniversityNanjingChina Department of Pediatrics Jinling HospitalMedical School of Nanjing UniversityNanjingChina Department of Pediatric Nephrology and Rheumatology The First Affiliated Hospital of Sun Yat-Sen UniversityGuangzhouChina Department of Pediatrics The Second Xiangya Hospital of Central South UniversityChangshaChina Department of Pediatrics Peking University First HospitalBeijingChina Department of Nephrology Beijing Children’s HospitalCapital Medical UniversityBeijing100045China National Center for Children’s Health BeijingChina Department of Pediatrics Shengjing Hospital of China Medical UniversityShenyangChina Department of Nephrology and Immunology Children’s Hospital of Soochow UniversitySuzhouChina Department of Nephrology Children HospitalZhejiang University School of MedicineHangzhouChina Department of Nephrology Wuhan Children’s Hospital(Wuhan Maternal and Child Healthcare Hospital)Tongji Medical CollegeHuazhong University of Science&TechnologyWuhanChina Department of Nephrology and Rheumatology Shanghai Children’s HospitalSchool

Background Pediatric antineutrophil cytoplasmic antibody-associated vasculitis(AAV)is a life-threatening systemic vasculitis featured by liability to renal ***,there are few studies on the risk factors and predictive models for renal outcomes of AAV in *** Data from 179 AAV children in multiple centers between January 2012 and March 2020 were collected *** risk factors and predictive model of end-stage renal disease(ESRD)in AAV were *** Renal involvement was the most typical manifestation(95.5%),and the crescent was the predominant pathological lesion(84.9%).The estimated glomerular filtration rate(eGFR)was evaluated in 114 patients,of whom 59.6%developed ESRD,and the median time to ESRD was 3.20 *** eGFR[P=0.006,odds ratio(OR)=0.955,95%confidence interval(CI)=0.924–0.987]and the percentages of global glomerulosclerosis(pGGS;P=0.018,OR=1.060,95%CI=1.010–1.112)were independent risk factors for ESRD of renal *** on the pGGS and eGFR at renal biopsy,we developed three risk grades of ESRD and one predictive *** Kaplan‒Meier curve indicated that renal outcomes were significantly different in different risk grades(P<0.001).Compared with serum creatinine at baseline,the predictive model had higher accuracy(0.86 versus 0.58,P<0.001)and a lower coefficient of variation(0.07 versus 0.92)in external *** Renal involvement is the most common manifestation of pediatric AAV in China,of which more than half deteriorates into *** predictive model based on eGFR at renal biopsy and the pGGS may be stable and accurate in speculating the risk of ESRD in AAV children.

关键词： Antineutrophil cytoplasmic antibody End-stage renal disease Glomerulonephritis Pediatric nephrology Vasculitis