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Control Theory and Technology 2024年第2期22卷 292-314页

作者： Yong Xiong Xianfei Wang Siwen Zhou School of Navigation Wuhan University of TechnologyWuhan430063HubeiChina National Engineering Research center for water Transport Safety Wuhan430063HubeiChina Hubei inland Technology Key Laboratory Wuhan430063HubeiChina

In this paper, the online parameter identification problem of the mathematical model of an unmanned surface vehicle (USV) considering the characteristics of the actuator is studied. A data-driven mathematical model of motion is very meaningful to realize trajectory prediction and adaptive motion control of the USV. An interactive identification algorithm (ESO–MILS, extended state observer–multi-innovation least squares) based on ESO is proposed. The robustness of online identification is improved by expanding the state observer to estimate the current disturbance without making artificial assumptions. Specifically, the three-degree-of-freedom dynamic equation of the double propeller propulsion USV is constructed. A linear model for online identification is derived by parameterization. Based on the least square criterion function, it is proved that the interactive identification method with disturbance estimation can improve the identification accuracy from the perspective of mathematical expectation. The extended state observer is designed to estimate the unknown disturbance in the model. The online interactive update improves the disturbance immunity of the identification algorithm. Finally, the effectiveness of the interactive identification algorithm is verified by simulation experiment and real ship experiment.

关键词： Identification of parameters Ship motion model Extended state observer Multinomial innovation least squares Interactive identification

Solute transport and geochemical modeling of the coastal quaternary aquifer, Delta Dahab Basin, South Sinai, Egypt

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Acta Geochimica 2024年第1期43卷 16-39页

作者： Amira Samy Mustafa Eissa Seham Shahen Moustafa M.Said Rabab M.Abou-shahaba Division of water Resources and Arid Land Department of HydrogeochemistryDesert Research CenterCairoEgypt Egypt Desalination Research center of Excellence Desert Research CenterCairoEgypt center for water Supply studies S&E-Physical&Environmental SciencesTexas A&M University Corpus ChristiCorpus ChristiUSA Department of Chemistry Faculty of Science(Girls)Al-Azhar UniversityYousef Abbas StrNasr CityP.O.Box:11754CairoEgypt

The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 890to 8213 mg/L, with a mean value of 3417 mg/L. The dissolved major ions have been used to calculate the seawater mixing index(SWMI) using a linear equation that discriminates the groundwater mostly affected by water–rock interaction(SWMI 1>) and other samples mixed with Seawater(SWMI water for specifically chosen groundwater samples ranges from-0.645‰ to +5.212‰ for δ^(18)O and from-9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sample(δ^(18)O + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochemical NETPATH model constrained by the dissolved significant ions, isotopes, and the rock aquifer forming minerals as phases indicate the mixing percent with the seawater ranges from 9% to 97% of seawater from 91% to 3% of original recharge water. According to the SEAWAT 3-D flow models, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m inland. The salt dissolution, upwelling of saline water, recharge from the upstream mountain block, and seawater encroachment are the primary aspects contributing to the deterioration of groundwater quality. These findings may have significance for effective groundwater withdrawal management in arid locations worldwide with similar hydrogeological systems.

关键词： Groundwater geochemistry Seawater intrusion Solute transport SEAWAT

Q-homotopy analysis method for time-fractional Newell–Whitehead equation and time-fractional generalized Hirota–Satsuma coupled KdV system

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Communications in Theoretical Physics 2024年第3期76卷 70-83页

作者： Di Liu Qiongya Gu Lizhen Wang center for Nonlinear studies School of MathematicsNorthwest UniversityXi'an710127China

In this paper,two types of fractional nonlinear equations in Caputo sense,time-fractional Newell–Whitehead equation(FNWE)and time-fractional generalized Hirota–Satsuma coupled KdV system(HS-cKdVS),are investigated by means of the q-homotopy analysis method(q-HAM).The approximate solutions of the proposed equations are constructed in the form of a convergent series and are compared with the corresponding exact *** to the presence of the auxiliary parameter h in this method,just a few terms of the series solution are required in order to obtain better *** the sake of visualization,the numerical results obtained in this paper are graphically displayed with the help of Maple.

关键词： fractional Newell-Whitehead equation fractional generalized Hirota-Satsuma coupled KdV system approximate solution q-homotopy analysis method

Recent advances and future prospects on Ni_(3)S_(2)-Based electrocatalysts for efficient alkaline water electrolysis

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Green Energy & Environment 2024年第4期9卷 659-683页

作者： Shiwen Wang Zhen Geng Songhu Bi Yuwei Wang Zijian Gao Liming Jin Cunman Zhang Clean Energy Automotive Engineering center School of Automotive StudiesTongji UniversityShanghai201804China

Green hydrogen(H_(2))produced by renewable energy powered alkaline water electrolysis is a promising alternative to fossil fuels due to its high energy density with zero-carbon ***,efficient and economic H_(2) production by alkaline water electrolysis is hindered by the sluggish hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Therefore,it is imperative to design and fabricate high-active and low-cost non-precious metal catalysts to improve the HER and OER performance,which affects the energy efficiency of alkaline water ***_(3)S_(2) with the heazlewoodite structure is a potential electrocatalyst with near-metal conductivity due to the Ni–Ni metal ***,the review comprehensively presents the recent progress of Ni_(3)S_(2)-based electrocatalysts for alkaline water ***,the HER and OER mechanisms,performance evaluation criteria,preparation methods,and strategies for performance improvement of Ni_(3)S_(2)-based electrocatalysts are *** challenges and perspectives are also analyzed.

关键词： Alkaline water electrolysis Hydrogen Electrocatalysts Ni_(3)S_(2)

Biosynthesized CS-MgO/zeolite hybrid material:An efficient adsorbent for chlorpyrifos removal-Kinetic studies and response surface methodology

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Emerging Contaminants 2024年第3期10卷 304-317页

作者： Mohammed T.M.H.Hamad Belal N.A.Mahran Central Laboratory for Environmental Quality Monitoring National Water Research CenterEgypt

The prevalence of organophosphate pesticides in aquatic environments raises severe concerns on a global ***,an insecticide,is included in a class of organophosphate *** is widely used on agricultural lands to control pests in cotton,fruit,and *** acute toxicity of chlorpyrifos is still dangerous to all aquatic living *** the treatment of water contaminated with chlorpyrifos is an important *** recent decade has witnessed adsorption technology emerging as an advanced organophosphate pesticide wastewater treatment with great potential and a grand blueprint,in which the specific surface area and active sites of the adsorbent are considered to be the two most important characteristics largely impacting the adsorption *** this study,a CS-MgO/Zeolite composite was prepared by the microbial method as an effective adsorbent for the removal of chlorpyrifos from an aqueous *** adsorbent's properties were carefully characterized using Xray diffraction,scanning electron microscopy,and Fourier-transform infrared *** refinement of experimental conditions,encompassing variations in adsorbent dosage,contact time,and chlorpyrifos concentration at five discrete levels,was systematically undertaken through the utilization of a composite central design rooted in response surface *** solution pH played a key role in chlorpyrifos removal,and a pH of 7.0 was selected according to its high adsorption *** highest removal(80.9%)of chlorpyrifos by CS-MgO/Zeolite was obtained at an optimum pH of 7,a contact time of 40 min,an adsorbent dosage of 0.4 g/L,and a chlorpyrifos concentration of 5 mg/L^(-1).The adsorption results were highly fitted with the Freundlich adsorption isotherm model,and the maximum adsorption was 83.3 mg/*** studies indicate that the removal of chlorpyrifos followed the pseudo-secondorder model of adsorption(0.994).The thermodynamic parameters indicate the sponta

关键词： Chlorpyrifos adsorption CS-MgO/Zeolite Response surface methodology

Cryogenic Digital Image Correlation as a Probe of Strain in Iron-Based Superconductors

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Chinese Physics Letters 2024年第10期41卷 84-89页

作者： Ziye Mo Chunyi Li Wenting Zhang Chang Liu Yongxin Sun Ruixian Liu Xingye Lu center for Advanced Quantum studies School of Physics and AstronomyBeijing Normal UniversityBeijing 100875China

Uniaxial strain is a powerful tuning parameter that can control symmetry and anisotropic electronic properties in iron-based ***,accurately characterizing anisotropic strain can be challenging and ***,we utilize a cryogenic optical system equipped with a high-spatial-resolution microscope to characterize surface strains in iron-based superconductors using the digital image correlation *** with other methods such as high-resolution x-ray diffraction,strain gauge,and capacitive sensor,digital image correlation offers a non-contact full-field measurement approach,acting as an optical virtual strain gauge that provides high spatial *** results measured on detwinned BaFe_(2)As_(2)are quantitatively consistent with the distortion measured by x-ray diffraction and neutron Larmor *** findings highlight the potential of cryogenic digital image correlation as an effective and accessible tool for probing the isotropic and anisotropic strains,facilitating applications of uniaxial strain tuning in research of quantum materials.

关键词： anisotropic gauge Probe

Quality assessment of the Topo-Iberia CGPS stations and data quality's effects on postfit ionosphere-free phase residuals

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Geodesy and Geodynamics 2024年第2期15卷 189-199页

作者： Juan A.García-Armenteros center for Advanced studies in Earth Sciences Energy and Environment(CEACTEMA)University of Jaén23071 JaenSpain

This paper analyzed GPS data from the Topo-Iberia network spanning almost 12 years(2008-2020).The data quality information for all 26 Topo-Iberia stations is provided for the first time,complementing the Spanish Geological Survey’s storage *** analyses based on quality indicators obtained using TEQC have been carried *** guidelines and data quality information from the IGS stations have been considered as the quality references,with the stations ALJI,EPCU,and TIOU standing out as the worst stations,while on the contrary,FUEN,PALM,PILA,and TRIA meet the quality requirements to become an IGS *** relationship between the GPS data quality and their GAMIT-and Gipsy X-derived postfit ionosphere-free phase residuals has also been investigated,and the results reveal an inversely proportional *** has been found that the stations showing an increase in elevation of the horizon line,also show an increase in cycle slips and multipath,are among the poorest quality stations,and among those with the highest postfit RMS of phase ***,the evolution of the vegetation around the antenna should be considered as it could cause a progressive loss of quality,which is not complying with the IGS *** quality assessment shows that the Topo-Iberia stations are appropriate for geodetic purposes,but permanent monitoring would be necessary to avoid the least possible loss of data and *** addition,a method to characterize the GNSS data quality is proposed.

关键词： GPS dataquality's effects IGS quality standard Postfit LC phase residual Qualityassessment Topo-Iberia CGPS network

Time-History Dynamic Characteristics of Reinforced Soil-Retaining Walls

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Structural Durability & Health Monitoring 2024年第6期18卷 853-869页

作者： Lianhua Ma Min Huang Linfeng Han Department of Building and Environmental Safety Chongqing Vocational Institute of Safety&TechnologyChongqing404120China National Engineering Research center for inland waterway Regulation Chongqing Jiaotong UniversityChongqing400074China

Given the complexities of reinforced soil materials’constitutive relationships,this paper compares reinforced soil composite materials to a sliding structure between steel bars and soil and proposes a reinforced soil constitutive model that takes this sliding into account.A finite element dynamic time history calculation software for composite response analysis was created using the Fortran programming language,and time history analysis was performed on reinforced soil retaining walls and gravity retaining *** vibration time histories of reinforced soil retaining walls and gravity retaining walls were computed,and the dynamic reactions of the two types of retaining walls to vibration were compared and *** dynamic performance of reinforced earth retaining walls was evaluated.

关键词： Reinforced earth retaining walls time history dynamic analysis finite element

Fe-N-C heterogeneous Fenton-like catalyst for the degradation of tetracycline:Fe-N coordination and mechanism studies

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Chinese Chemical Letters 2024年第9期35卷 309-314页

作者： Weichen Zhu Wei Zuo Pu Wang Wei Zhan Jun Zhang Lipin Li Yu Tian Hong Qi Rui Huang State Key Laboratory of Urban water Resource and Environment(SKLUWRE) School of EnvironmentHarbin Institute of TechnologyHarbin 150090China Guangdong Yuehai water Investment Co. Ltd.Shenzhen 518021China National Engineering Research center of Urban water Resources Co. Ltd.Harbin Institute of TechnologyHarbin 150090China

Fe-N-C materials have received increasing attention,due to its distinctive catalytic ***,the Fe-N coordination number dependence of catalytic ability and mechanism for H_(2)O_(2)activation remain ***,a series of Fe-N-C heterogeneous Fenton-like catalysts with different Fe-N coordination number were prepared for tetracycline *** results demonstrated that samples with Fe-N4 structure exhibited high *** excellent performance was mainly ascribed to the high adsorption capacity and the formation of superoxide radicals(•O_(2)^(−))catalyzed by Fe linked to pyridinic *** intermediates and degradation pathways of tetracycline degradation by Fe-N-C/H_(2)O_(2)system were analyzed by liquid chromatography coupled to tandem mass spectrometry(LC-MS/MS).Furthermore,we applied our Fe-N-C catalysts to treat simulated pharmaceutical wastewater with high tetracycline degradation capacity despite high concentrations of organic matter such as oxalic acid and various ionic *** work reveals the dependence of the activation H_(2)O_(2)on the Fe-N coordination environment and the degradation mechanism of these *** provides insights into the prospects for tuning the catalyst in practical applications.

关键词： H_(2)O_(2)activation Advanced oxidation process Superoxide radicals Degradation pathways EXAFS

Visible-light-induced organocatalyzed C（sp2）–H bond functionalization of 1,3-azoles with trifluoroacetylsilanes

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Science China Chemistry 2024年第11期67卷 3662-3668页

作者： Zhengyu Li Zeguo Zhang Zhihan Zhang Gang Zhou Yizhi Zhang Shanshan Liu Xiao Shen The Institute for Advanced studies Engineering Research Center of Organosilicon Compounds & Materials Ministry of EducationWuhan University College of Chemistry Central China Normal University

Previous carbene insertion to C–H bonds of 1,3-azoles relied on metal carbene species. Herein, we report a metal-free C（sp2）–H bond functionalization of 1,3-azoles with trifluoroacetylsilanes. The reaction features mild conditions, broad substrate scope and wide functional group tolerance. The mechanistic study supports that the success of the reaction is probably attributed to the dual roles of trifluoroacetylsilanes under the photocatalyzed conditions: generating carbenes which undergo cyclopropanation and generating biradicals which promote ring-opening aromatization of the in situ generated fused cyclopropanes.

关键词： C(sp2)–H bond functionalization carbenes biradicals cyclopropanation brook rearrangement