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Chinese Journal of Chemistry 2024年第2期42卷 151-156页

作者： Ming Yang Xin-yu Wang Jie Wang yu-long Zhao Jilin Province Key Laboratory of Organic Functional Molecular Design&Synthesis Faculty of ChemistryNortheast Normal UniversityChangchunJilin 130024China

A photocatalytic[3+2]annulation of alkenes with vinyl azides was developed under irradiation by visible light in the presence of organic dye *** substrate scope and high functional group tolerance were demonstrated by more than 50 *** reaction provides a novel and efficient method for the synthesis of polyfunctionalized pyrroles under very mild metal-free conditions without other additives.

关键词： Photocatalysis Vinyl azides Alkenes Pyrroles Annulation Radical reactions

Numerical Simulation of the Mass Movement Process of the 2018 Sedongpu Glacial Debris Flow by Using the Fluid-Solid Coupling Method

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Journal of Earth Science 2024年第2期35卷 583-596页

作者： Xing-yu long yu-Xiang Hu Bin-Rui Gan Jia-Wen Zhou State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu610065China College of Water Resource and Hydropower Sichuan UniversityChengdu610065China

In the context of global warming and intensified human activities,glacier instability in plateau regions has increased,and glacier debris flows have become active,which poses a significant threat to the lives and property of people and socioeconomic *** mass movement process of glacier debris flows is extremely complex,so this paper uses the 2018 Sedongpu glacier debris flow event on the Qinghai-Tibet Plateau as an example and applies a numerical simulation method to invert the whole process of mass *** view of the interaction between phases in the process of motion,we use the fluid-solid coupling method to describe the mass *** granular-flow model and drift-flux model are employed in FLOW3D software to study the mass movement process of glacier debris flows and explore their dynamic *** results indicate that the glacier debris flow lasted for 700 s,and the movement process was roughly divided into four stages,including initiation,scraping,surging and deposition;the depositional characteristics calculated by the fluid-solid coupling model are consistent with the actual survey results and have good reliability;strong erosion occurs during the mass movement,the clear volume amplification effect,and the first wave climbs 17.8 m across the *** fluid-solid coupling method can better simulate glacier debris flows in plateau regions,which is helpful for the study of the mechanism and dynamic characteristics of such disasters.

关键词： glacial debris flow Qinghai-Tibet Plateau fluid-solid coupling FLOW3D mass movement depositional characteristics disasters engineering geology

Effectiveness of urban distributed runoff model for discharge and water depth calculation in urban drainage pipe networks

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Journal of Hydrodynamics 2024年第3期36卷 582-591页

作者： Yang Zhou Yi-ling Leng Peng-yu Wang Shang-hong Zhang yu-long Zhu yu-jun Yi School of Water Resources and Hydropower Engineering North China Electric Power UniversityBeijing102206China State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing100875China

Effective urban land-use re-planning and the strategic arrangement of drainage pipe networks can significantly enhance urban flood defense *** at reducing the potential risks of urban flooding,this paper presents a straightforward and efficient approach to an urban distributed runoff model(UDRM).The model is developed to quantify the discharge and water depth within urban drainage pipe networks under varying rainfall intensities and land-use *** Nash efficiency coefficient of UDRM exceeds 0.9,which indicates its high computational efficiency and potential benefit in predicting urban *** prediction of drainage conditions under both current and re-planned land-use types is achieved by adopting different flood recurrence *** findings reveal that the re-planned land-use strategies could effectively diminish flood risk upstream of the drainage pipe network across 20-year and 50-year flood recurrence ***,in the case of extreme rainfall events(a 100-year flood recurrence),the re-planned land-use approach fell short of fulfilling the requirements necessary for flood disaster *** these instances,the adoption of larger-diameter drainage pipes becomes an essential requisite to satisfy drainage ***,the proposed UDRM effectively combines land-use information with pipeline data to give practical suggestions for pipeline modification and land-use optimization to combat urban ***,this methodology warrants further promotion in the field of urban re-planning.

关键词： Stormwater runoff water depth urban distributed runoff model urban drainage pipe networks urban land-use re-planning

Consistent and Accurate TDOA Localization in Dynamic NLOS Environments via Prior Information Independent Estimation

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China Communications 2024年第9期21卷 198-210页

作者： Luo Mei long yu Xiong Youzhi Qin Shuang Key Laboratory of Wireless Sensor Network in University of Sichuan Province College of Physics and Electronic EngineeringSichuan Normal UniversityChengdu 610101China

In the time-difference-of-arrival(TDOA)localization,robust least squares(LS)problems solved by mathematical programming were proven to be superior in mitigating the effects of non-line-of-sight(NLOS)***,the existing algorithms still suffer from two disadvantages:1)The algorithms strongly depend on prior information;2)The approaches do not satisfy the mean square error(MSE)optimal criterion of the measurement *** tackle the troubles,we first formulate an MSE minimization model for measurement noise by taking the source and the NLOS biases as *** obtain stable solutions,we introduce a penalty function to avoid abnormal *** further tackle the nonconvex locating problem with semidefinite relaxation ***,we incorporate mixed constraints and variable information to improve the estimation *** and experiments show that the proposed method achieves consistent performance and good accuracy in dynamic NLOS environments.

关键词： mathematical programming NLOS mitigation robust least squares TDOA

Phase behavior of gas condensate in porous media using real-time computed tomography scanning

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Petroleum Science 2024年第2期21卷 1032-1043页

作者： Wen-long Jing Lei Zhang Ai-Fen Li Jun-Jie Zhong Hai Sun Yong-Fei Yang yu-long Cheng Jun Yao Institute of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina

The phase behavior of gas condensate in reservoir formations differs from that in pressure-volume-temperature(PVT)cells because it is influenced by porous media in the reservoir *** was used as a sample to investigate the influence of porous media on the phase behavior of the gas *** pore structure was first analyzed using computed tomography(CT)scanning,digital core technology,and a pore network *** sandstone core sample was then saturated with gas condensate for the pressure depletion *** each pressure-depletion state was stable,realtime CT scanning was performed on the *** scanning results of the sample were reconstructed into three-dimensional grayscale images,and the gas condensate and condensate liquid were segmented based on gray value discrepancy to dynamically characterize the phase behavior of the gas condensate in porous *** network models of the condensate liquid ganglia under different pressures were built to calculate the characteristic parameters,including the average radius,coordination number,and tortuosity,and to analyze the changing mechanism caused by the phase behavior change of the gas *** types of condensate liquid(clustered,branched,membranous,and droplet ganglia)were then classified by shape factor and Euler number to investigate their morphological changes dynamically and *** results show that the dew point pressure of the gas condensate in porous media is 12.7 MPa,which is 0.7 MPa higher than 12.0 MPa in PVT *** average radius,volume,and coordination number of the condensate liquid ganglia increased when the system pressure was between the dew point pressure(12.7 MPa)and the pressure for the maximum liquid dropout,Pmax(10.0 MPa),and decreased when it was below *** volume proportion of clustered ganglia was the highest,followed by branched,membranous,and droplet *** study provides crucial experimental evidence for the phase behavior chan

关键词： Gas condensate Pressure depletion Real-time micro-computed tomography scanning Distribution of condensate liquid

Microstructure,wear and friction behavior of CoCrAITaY-xCNTs composite coatings deposited by laser-induction hybrid cladding

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Rare Metals 2024年第4期43卷 1815-1827页

作者： Sheng-Feng Zhou yu long Yan-Liang Yi Cheng Deng Lian-Xi Hu Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China MOE Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning530004China School of Mechatronics Engineering Guangdong Polytechnic Normal UniversityGuangzhou510635China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes(CNTs)chemically reacted with Ta to form reinforcement phase(TaC),while the other CNTs were retained as lubrication ***,the CoCrAlYTa-xCNTs(x=0,1,2,and 4;wt%)composite coatings were prepared by laserinduction hybrid cladding(LIHC),and the microstructure and wear resistance of coatings were systematically *** show that the coatings are mainly composed of TaC,y-(Co,Cr)andβ-(Co,Cr)*** the CNTs content increases from 0 wt%to 4 wt%,the volume fraction of TaC increases from 13.11 vol%to 16.12 vol%.Meanwhile,the nano-hardness ofγ-(Co,Cr)andβ-(Co,Cr)Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,*** a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4×10^(-3)to 6.1×10^(-3)mg·m^(-1),and the average friction coefficient decreases from 0.55 to *** good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding

Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

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Defence Technology（防务技术） 2024年第1期31卷 580-593页

作者： Zheng-qing Zhou Ze-chen Du Xiao Wang Hui-ling Jiang Qiang Zhou yu-long Zhang yu-zhe Liu Pei-ze Zhang Research Institute of Macro-Safety Science University of Science and TechnologyBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China School of Mechanical Engineering Nantong UniversityNantong226019China China North Industry Advanced Technology Generalization Institute Beijing100089China China Academy of Ordnance Science China

As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive *** this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were *** the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(SEM) and electron backscattered diffraction(EBSD).The observation result shows that many slip bands(SBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro *** addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the *** stress parameters of the observation points were obtained through an effective numerical *** mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro *** result shows that the generation and expansion of micro defects are related to the stress area(*** upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile ***,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(*** horizontal direction) were also *** was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only SBs and a few micro cracks,and the those decrea

关键词： Explosive load Quasi-cracking area Micro defects Steel plate Dynamic response Numerical simulation

3D-printed self-healing,biodegradable materials and their applications

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Frontiers of Mechanical Engineering 2024年第3期19卷 1-22页

作者： yu LI Guangmeng MA Fawei GUO Chunyi LUO Han WU Xin LUO MingtaoZHANG Chenyun WANG Qingxin JIN yu long School of Mechanical Engineering Guangxi UniversityNanning 530004China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi UniversityNanning 530004China Institute of Laser Intelligent Manufacturing and Precision Processing School of Mechanical EngineeringGuangxi UniversityNanning 530004China College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China

3D printing is a versatile technology capable of rapidly fabricating intricate geometric structures and enhancing the performance of flexible devices in comparison to conventional fabrication ***,3D-printed devices are susceptible to failure as a result of minuscule structural impairments,thereby impacting their overall *** utilization of self-healing,biodegradable materials in 3D printing holds immense potential for increasing the longevity and safety of devices,thereby expanding the application prospects for such ***,enhancing the self-repairing capability of devices and refining the 3D printing performance of self-healing materials are still considerable challenges that need to be addressed to achieve optimal *** paper reviews recent developments in the field of advancements in 3D printing using self-healing and biodegradable ***,it investigates self-healing and biodegradable materials that are compatible with 3D printing techniques,discussing their printability,material properties,and factors that influence print ***,it explores practical applications of selfhealing and biodegradable 3D printing technology in ***,it critically offers practical perspectives on this topic.

关键词： 3D printing self-healing biodegradable soft materials covalent bonds non-covalent bonds

Males armed with big weapons win fights at limited cost in ant-mimickingjumping spiders

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Current Zoology 2024年第1期70卷 98-108页

作者： Guocheng yu Boon Hui Wong Christina J.Painting Hongze Li long yu Zengtao Zhang Shichang Zhang Daiqin Li State Key Laboratory of Biocatalysis and Enzyme Engineering and Centre for Behavioral Ecology and Evolution School of Life SciencesHubei UniversityWuhan430062China Departmentof Biological Sciences National University of Singapore14 Science Drive 4Singapore 117543Singapore Te Aka Matuatua School of Science University of WaikatoPrivate Bag 3105Hamilton 3240New Zealand

A core assumption of sexual selection theory is that sexually selected weapons,specialized morphological structures used directly in male con-tests,can improve an individual's reproductive success but only if the bearer can overcome associated costs,the negative effects on the bear-er's fitness ***,recent studies have shown that producing and wielding exaggerated weapons may not necessarily be ***,some traits can be selected for supporting,or compensating for,the expense of producing and wielding such exaggerated weapons.n the ant-mimicking jumping spider Myrmarachne gisti,exaggerated chelicerae are borne only by adult males and not females,showing sexual dimorphism and steep positive allometry with body ***,we determine the potential benefits of bearing exaggerated chelicerae during male contests and explore the potential for costs in terms of prey-capture efficiency and compensation between chelicera size and neighboring trait *** males with longer chelicerae won most of their male-male contests,we found no significant differences in prey-capture effi-ciency between males and females regardless of whether prey was winged or ***'elongated chelicerae thus do not impede their efficiency at capturing ***,we found that the sizes of all neighboring traits are positively correlated with chelicera size,suggesting that these traits may be under correlational *** together,our findings suggest that *** males armed with the exaggerated chelicerae that function as weapons win more fights at limited cost for performance in prey capture and compensate for neighboring structures.

关键词： allometry ant-mimic costs elongated chelicerae threat devices trait compensations

Boosted Electrocatalytic Glucose Oxidation Reaction on Noble-Metal-Free MoO_(3)-Decorated Carbon Nanotubes

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Transactions of Tianjin University 2024年第1期30卷 63-73页

作者： yu-long Men Ning Dou Yiyi Zhao Yan Huang Lei Zhang Peng Liu Department of Chemical Engineering School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Thyroid Breast and Vascular Surgery Shanghai Fourth People’s Hospital Affi liated to Tongji University School of MedicineShanghai 200081China Department of Vascular Surgery Changhai HospitalNaval Medical UniversityShanghai 200433China

Electrocatalytic glucose oxidation reaction(GOR)has attracted much attention owing to its crucial role in biofuel cell ***,we load MoO_(3)nanoparticles on carbon nanotubes(CNTs)and use a discharge process to prepare a noblemetal-free MC-60 catalyst containing MoO_(3),Mo_(2)C,and a Mo_(2)C–MoO_(3)*** the GOR,MC-60 shows activity as high as 745μA/(mmol/L cm^(2)),considerably higher than those of the Pt/CNT(270μA/(mmol/L cm^(2)))and Au/CNT catalysts(110μA/(mmol/L cm^(2))).In the GOR,the response minimum on MC-60 is as low as 8μmol/L,with a steady-state response time of only 3 ***,MC-60 has superior stability and anti-interference ability to impurities in the *** better performance of MC-60 in the GOR is attributed to the abundant Mo sites bonding to C and O atoms at the MoO_(3)–Mo_(2)C *** Mo sites create active sites for promoting glucose adsorption and oxidation,enhancing MC-60 performance in the ***,these results help to fabricate more effi cient noble-metal-free catalysts for the fabrication of glucose-based biofuel cells.

关键词： Interface eff ect Electrocatalysis Molybdenum oxide Glucose Oxidation reaction