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Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and Recovery of Torpedo-Shaped Autonomous Underwater Vehicle

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China Ocean Engineering 2024年第3期38卷 453-466页

作者： ZHANG Guo-xing XIA Xin-lu GUO Jin-wei School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological ***,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain ***,the screw theory is employed to analyze the degree of freedom(DoF)of the capture ***,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried *** with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried ***,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are ***,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is *** work provides technical reserves for the research and development of AUV capture special equipment.

关键词： capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis

Impact of Mo/Ni alloying on microstructural modulation and low-temperature toughness of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1746-1762页

作者： wei Liu Hong-li Zhao Bing-xing Wang Yong Tian State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

The high-strength low-alloy steel plates with varying Ni/Mo contents were manufactured using the thermos-mechanical control *** investigation was conducted to explore the effect of Ni/Mo microalloying on microstructure evolution and mechanical properties of the *** results revealed that the increase in Ni content from 1 to 2 wt.%reduced the transition temperature of ferrite and the growth range of ferritic grain was narrowed,which promoted grain *** optimized combination of grain size,high-angle grain boundaries(HAGBs),and martensite-austenite(M-A)islands parameter contributed to the excellent impact toughness of S1 steel at-100℃(impact absorbed energy of 218.2 J at-100℃).As the Mo increases from 0 to 2 wt.%,the matrix structure changes from multiphase structure to granular bainite,which increases the average effective grain size to~4.62 pm and reduces HAGBs proportion to~36.22%.With these changes,the low-temperature impact toughness of S3 steel is *** addition,based on the analysis of the characteristics of crack propagation path,it was found that M-A islands with low content(~2.21%)and small size(~1.76 pm)significantly retarded crack propagation,and the fracture model of M-A islands with different morphologies was further ***,correlation between behaviour of delamination and toughness was further analysed by observing delamination size and impact energy parameters.

关键词： High-strength low-alloy steel Microstructural regulation Ni addition Mo addition Crack propagation Low-temperature toughness

An Adaptive Local Grid Nesting-based Genetic Algorithm for Multi-earth Observation Satellites' Area Target Observation

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Journal of Systems Science and Systems Engineering 2024年第2期33卷 232-258页

作者： Ligang xing wei Xia Xiaoxuan Hu Waiming Zhu Yi Wu School of Management Hefei University of TechnologyHefei 230009China Key Laboratory of Process Optimization and Inteligent Decision-making Ministry of EducationHefei 230009China Intelligent Interconnected Systems Laboratory of Anhui Province Hefei 230009China

The Scheduling of the Multi-EOSs Area Target Observation(SMEATO)is an EOS resource schedul-ing problem highly coupled with computational *** advances in EOS technology and the ex-pansion of wide-area remote sensing applications have increased the practical significance of *** this paper,an adaptive local grid nesting-based genetic algorithm(ALGN-GA)is proposed for developing SMEATO ***,a local grid nesting(LGN)strategy is designed to discretize the target area into parts,so as to avoid the explosive growth of calculations.A genetic algorithm(GA)framework is then used to share reserve information for the population during iterative evolution,which can generate high-quality solutions with low computational *** this basis,an adaptive technique is introduced to determine whether a local region requires nesting and whether the grid scale is *** effectiveness of the proposed model is assessed experimentally with nine randomly generated tests at different *** results show that the ALGN-GA offers advantages over several conventional algorithms in 88.9%of instances,especially in large-scale *** fully demonstrate the high efficiency and stability of the ALGN-GA.

关键词： Multi-EOSs scheduling area target observation adaptive genetic algorithm local grid nesting

Rational design and energy catalytic application of high-loading single-atom catalysts

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Rare Metals 2024年第10期43卷 4844-4866页

作者： Zi-wei Deng Yue Liu Jie Lin Wen-xing Chen Energy and Catalysis Center School of Materials Science and EngineeringBeijing Institute of Technology Ningbo Institute of Materials Technology and Engineering Chinese Academy of Science

It is well known that single-atom catalysts(SACs)have become a hot topic in the field of catalysis due to their advantages such as 100% metal atom utilization efficiency,high catalytic activity and selectivity compared with conventional catalysts and nanocatalysts. However, the isolated metal atoms on SACs have thermodynamic instability and tend to agglomerate, which limit their catalytic ***, it is of great significance to synthesize stable and high-loading single-atom catalysts(HLSACs). In this paper,we review the research progress of HLSACs from two aspects:design and application. Firstly, we comprehensively introduce the synthesis strategies of HLSACs, namely, top-down and bottom-up methods. Secondly, we overview the application status of HLSACs in three fields: electrocatalysis, thermal catalysis and photocatalysis. Finally, we summarize the development prospects and challenges of HLSACs.

关键词： Design Electrocatalysis High-loading single-atom catalysts Photocatalysis Thermal catalysis

Metallosalen covalent organic frameworks for heterogeneous catalysis

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Interdisciplinary Materials 2024年第1期3卷 87-112页

作者： wei Zhou wei‐Qiao Deng xing Lu School of Chemistry and Chemical Engineering Hainan UniversityHaikouHainanChina Institute of Molecular Sciences and Engineering Shandong UniversityQingdaoShandongChina

Metallosalen covalent organic frameworks(M(salen)-COFs)have garnered significant attention as promising candidates for advanced heterogeneous catalysis,including organocatalysis,electrocatalysis,and photocatalysis,due to their unique structural advantages(combining molecules catalysts and crystalline porous materials)and tunable topological *** is essential to provide a comprehensive overview of emerging designs of M(salen)-COFs and corresponding advances in this ***,this review first summarizes the reported metallolinkers and the synthesis methods of M(salen)-*** addition,the review enumerates the excellent M(salen)-COF based heterogeneous catalysts and discusses the fundamental mechanisms behind the outstanding heterogeneous catalytic performance of M(salen)-*** mechanisms include the pore enrichment effect(enhancing local concentration within porous materials to promote catalytic reactions),the three-in-one strategy(integrating enrichment,reduction,and oxidation sites in one system),and the incorporation of a built-in electric field(implanting a built-in electric field in heterometallic phthalocyanine covalent organic frameworks).Furthermore,this review discusses the challenges and prospects related to M(salen)-COFs in heterogeneous catalysis.

关键词： covalent organic frameworks heterogeneous catalysis metallosalen

Viscoacoustic generalized screen propagator in constant-Q model

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Petroleum Science 2024年第4期21卷 2356-2369页

作者： Zhong-Kui Dai Jia-Chun You xing-Guo Huang wei Liu College of Geophysics Chengdu University of Technology College of Instrumentation and Electrical Engineering Jilin University

When seismic waves propagate through the geological formation, there is a significant loss of energy and a decrease in imaging resolution, because of the viscoacoustic properties of subsurface medium. This profoundly impacts seismic wavefield propagation, imaging and interpretation. To accurately image the true structure of subsurface medium, the consensus among geophysicists is to no longer treat subsurface medium as ideal homogeneous medium, but rather to incorporate the viscoacoustic properties of subsurface medium. Based on the generalized screen propagator using conventional acoustic wave equation(acoustic GSP), our developed method introduces viscoacoustic compensation strategy, and derives a one-way wave generalized screen propagator based on time-fractional viscoacoustic wave equation(viscoacoustic GSP). In numerical experiments, we conducted tests on two-dimensional multi-layer model and the Marmousi model. When comparing with the acoustic GSP using the acoustic data, we found that the imaging results of the viscoacoustic GSP using the viscoacoustic data showed a significant attenuation compensation effect, and achieved imaging results for both algorithms were essentially consistent. However, the imaging results of acoustic GSP using viscoacoustic data showed significant attenuation effects, especially for deep subsurface imaging. This indicates that we have proposed an effective method to compensate the attenuated seismic wavefield. Our application on a set of real seismic data demonstrated that the imaging performance of our proposed method in local areas surpassed that of the conventional acoustic GSP. This suggests that our proposed method holds practical value and can more accurately image real subsurface structures while enhancing imaging resolution compared with the conventional acoustic GSP. Finally, with respect to computational efficiency, we gathered statistics on running time to compare our proposed method with conventional Q-RTM, and it is evid

关键词： One-way wave equation Viscoacoustic wave equation Generalized screen propagator Attenuation and dispersion effects

Texture and Se vacancy optimization induces high thermoelectric performance in Bi_(2)Se_(3) flexible thin films

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Rare Metals 2024年第6期43卷 2796-2804页

作者： Dong-wei Ao wei-Di Liu Yue-xing Chen Fan Ma Yi-Jie Gu Zhuang-Hao Zheng School of Machinery and Automation Weifang UniversityWeifang 261061China Australian Institute for Bioengineering and Nanotechnology The University of QueenslandBrisbane 4072Australia Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen518060China School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China

Bi_(2)Se_(3)-based flexible thin film with high thermoelectric performance is promising for the waste heat recovery *** this work,a novel post-selenization method is employed to prepare n-type Bi_(2)Se_(3)flexible thin films with highly textured *** strengthened texture and Se vacancy optimization can be simultaneously achieved by optimizing the selenization *** highly oriented texture leads to the increased carrier mobility and results in a high electric conductivity of~290.47 S·cm^(-1)at 623 ***,a high Seebeck coefficient(>110μW·K-1)is obtained due to the reduced carrier concentration,induced by optimizing vacancy ***,a high power factor of 3.49μW·cm^(-1)·K^(-2)at 623 K has been achieved in asprepared highly-bendable Bi_(2)Se_(3)flexible thin films selenized at 783 *** study introduces an effective post-selenization method to tune the texture structure and vacancies of Bi_(2)Se_(3)flexible thin films,and correspondingly achieves high thermoelectric performance.

关键词： Thermoelectric Bi_(2)Se_(3) Flexible thin film Post-selenization

Unraveling the hydraulic properties of loess for landslide prediction:A study on variations in loess landslides in Lanzhou,Dingxi,and Tianshui,China

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China Geology 2024年第2期7卷 291-302页

作者： Gao-chao Lin wei Liu xing Su School of Civil and Environmental Engineering University of New South WalesSydneyNSW 2052Australia Institute of Transportation Inner Mongolia UniversityHohhot 010070China Institute of Geological Hazards Prevention Gansu Academy of SciencesLanzhou 730000China

Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re *** involvement of water repre sents a critical factor in inducing loess *** study focuses on three neighboring cities sequentially situated on the Loess Plateau along the direction of aeolian deposition of loess,namely Lanzhou,Dingxi,and Tianshui,which are densely populated and prone to landslide *** variations in hydraulic properties,including water retention capacity and permeability,are investigated through Soil Water Characteristic Curve(SWCC)test and hydraulic conductivity *** experimental findings revealed that Tianshui loess exhibited the highest water retention capacity,followed by Dingxi loess,while Lanzhou loess demonstrated the lowest water retention ***,the results for the saturated permeability coefficient were found to be the opposite:Tianshui loess showed the lowest permeability,whereas Lanzhou loess displayed the highest *** results are supported and analyzed by scanning electron microscopy(SEM)*** addition,the water retention capacity is mathematically expressed using the van Genuchten model and extended to predict unsaturated hydraulic properties of *** experimental results exhibit a strong accordance with one another and align with the regional distribution patterns of disasters.

关键词： Loess Landslide Hydraulic properties Water retention capacity and permeability Soil Water Characteristic Curve(SWCC) Hydraulic conductivity Van Genuchten model Hydrogeological engineering Geological hazards prevention engineering

High Permeability in Broadband of Co-sputtered [Fe-Fe_(20)Ni_(80)/Cr]_(n) Multilayer Films

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 410-416页

作者：罗创钰 LIU xing 王峰李维 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China College of Materials and Chemical Engineering Hezhou UniversityHezhou 542899China

To achieve high microwave permeability in wide-band for the micron-thick magnetic films,[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer structure was proposed by co-sputtering Fe and FeNi to form the magnetic layers and Cr to form the *** multilayer structure contributes to the high permeability by reducing the coercivity and diminishing out-of-plane *** maximum imaginary permeability of[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer film reaches a large value of 800 at 0.52 GHz even though its overall thickness exceeds 1μ***,the magnetic resonance frequency of the multilayer film can be modulated from 0.52 to 1.35 GHz by adjusting the sputtering power of Fe from 0 to 86 W,and its bandwidth for μ’’>200(Δf) is as large as 2.0 *** desirable broad Δf of magnetic permeability,which can be well fitted by the Landau-Lifshitz-Gilbert equations,is due to dual magnetic resonances originated from double magnetic phases of Fe and FeNi that are of different saturation *** micron-thick multilayer films with high permeability in extended waveband are promising candidate for electromagnetic noise suppression application.

关键词： magnetron sputtering multiple magnetic resonance high permeability electromagnetic noise suppression