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Characterization of Nutrients,Heavy Metals,Petroleum and Their Impact on Phytoplankton in Laizhou Bay:Implications for Environmental Management and Monitoring

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Journal of Ocean University of China 2024年第3期23卷 822-834页

作者： WANG Kai ZHAO Linlin ZHU Yugui YANG Liqiang WANG Yunfeng HONG Xuguang college of marine Life Science Ocean University of ChinaQingdao 266003China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China college of Fisheries Ocean University of ChinaQingdao 266003China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Southern marine Science and engineering Guangdong Laboratory Guangzhou 511458China

The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental *** study provides a comprehensive characterization of nutrients,petroleum,heavy metals,and phytoplankton community structure across seven distinct areas in *** results indicate relatively high concentrations of NO_(2)-N,SiO_(4)-Si,and NO_(3)-N in the Southwest Laizhou Bay(SWLB)and Huanghe River Estuary(HRE).In contrast,the East Laizhou bay(ELB)and the North of Huanghe River Estuary(NHRE)exhibit the highest concentrations of heavy metals(As,Cr and Hg).The areas with high phytoplankton density and community diversity are mainly located in the *** adjusting for basic environmental factors,phytoplankton density and Margalef richness index D are significantly associated with nutrients(NO_(3)-N,NO_(2)-N,NH_(4)-N,SiO_(4)-Si),and heavy metal(Cr)*** highlight that,in addition to Xiaoqinghe River,nutrients brought by the Mihe River in the SWLB and heavy metal(Cr)pollution in the ELB resulting from industrial and mining activities along the coast significantly influence phytoplankton growth and community ***,it is recommended that more monitoring and management efforts be focused on these regions in the future.

关键词： Huanghe River Estuary Laizhou Bay nutrients heavy metals phytoplankton biodiversity

Direction finding characteristics of the bio-sonar model of a big brown bat

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Chinese Journal of Acoustics 2024年第3期43卷 380-395页

作者： WANG Feng LU Yuqing DONG Yangze college of Information Science and engineering Hohai UniversityNanjing211100 Southern marine Science and engineering Guangdong Laboratory Zhanjiang524000

A bionic model of bat bio-sonar is established through computer simulation in this study,with a focus on investigating itsorientation measurement performance.A model for simulating bat orientation perception is created via a binaural broadband interferometer,utilizing binaural interference *** model incorporates a convolutional neural network(CNN)to achieve extraction and perception of orientation ***,the principle of multi-frequency point defuzzification is elaborated upon in the *** simulation results reveal the proposed bionic model achieves a direction measurement accuracy of 0.87◦and 0.116◦in the rough search mode and precise search mode,respectively,at a signal-to-noise ratio of 25 *** model demonstrates high accuracy in orientation recognition and defuzzification *** to the technique that employs broad phase difference to determine target orientation information,the proposed model exhibits analogous direction finding efficiency but superior defuzzification capacity.

关键词： finding utilizing precise

Achieving superior performance in powder-metallurgy near-βtitanium alloy by combining hot rolling and rapid heat treatment followed by aging

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Journal of Materials Science & Technology 2024年第4期171卷 24-36页

作者： Fucheng Qiu Tuo Cheng Yuchao Song Orest M.Ivasishin Dmytro G.Savvakin Guangyu Ma Huiyan Xu college of Materials Science and engineering Jilin UniversityChangchun 130025China International Center of Future Science Jilin UniversityChangchun 130025China G.V.Kurdyumov Institute for Metal Physics KyivUkraine college of biological and Agricultural Jilin UniversityChangchun 130025China

Heat treatment plays an important role in tailoring the mechanical properties of powder-metallurgy(PM)titanium ***,only limited work about the rapid heat treatment(RHT)of PM titanium alloys has been *** this work,RHT was applied to PM Ti-5Al-5Mo-5V-1Cr-1Fe alloy after hot rolling to study the evolution of its mechanical properties and the influence of residual pores on its *** hot rolling and annealing,a fine and uniformα+βstructure with few residual pores is *** RHT,the primaryαdissolves gradually and completes in theβregion,and theβgrains then grow,resulting in the continuous decrease in elongation after ***,the tensile strength first increases and then decreases with increasing RHT temperature,owing to the increase in volume fraction of secondaryαinα+βregion and theβgrain growth inβ*** contrast to the RHT of cast-and-wrought titanium,the negative influence of residual pores lowers the RHT temperature for obtaining the highest tensile strength to a temperature below theβ-transus *** the negative influence of the residual pores,retained primaryαand fineβgrains with fine secondaryαinside contribute to achieving a good strength/ductility balance(1570 MPa and 6.1%,respectively).Addi-tionally,although at higher cycles to failure,the negative influence of residual pores increases as it affects the crack initiation zone at the subsurface,the good resistance of secondaryαto fatigue crack propaga-tion still enhances the fatigue strength considerably(about 300 MPa).This work suggests a cost-effective strategy to produce titanium alloys with high performance.

关键词： Rapid heat treatment Powder metallurgy Mechanical properties Near-βtitanium Residual pores

Parametric investigation on the novel and cost-effective nano fly ash impregnated geopolymer system for sustainable construction

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Frontiers of Structural and Civil engineering 2024年第2期18卷 170-183页

作者： R.MOHANA S.M.Leela BHARATHI Department of Civil engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environmental effects of greenhouse gas emissions and climate change demand alternative sources for cementitious materials in the construction *** development of geopolymer structures provides a way of producing 100%cement-free *** this research work,a novel and simple way of deriving nano particles from waste fly ash particles is *** effect of adding the synthesized nano fly ash particles as a filler medium in geopolymer mortars was investigated by considering strength and durability *** optimization was done by using regression analysis on the geopolymer mortar and the impact of adding nano fly ash particles was studied by varying different percentages of addition ranging from 0 to 7.5%by weight of binder *** the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polymerization process,resulting in denser geopolymer *** can explain the extraordinary gain in strength of 72.11 MPa as well as the denser core with negligible level of chloride ion penetration,making the material suitable for the development of structures susceptible to marine environment.

关键词： geopolymer nano fly ash chloride ion penetration durability polymerization fillers

Optimization Design of the Multi-Layer Cross-Sectional Layout of An Umbilical Based on the GA-GLM

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China Ocean engineering 2024年第2期38卷 247-254页

作者： YANG Zhi-xun YIN Xu FAN Zhi-rui YAN Jun LU Yu-cheng SU Qi MAO Yandong WANG Hua-lin Institute of marine machinery College of Mechanical and Electrical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDepartment of Engineering MechanicsDalian University of TechnologyDalian 116024China Ningbo Institube of Dalian University of Technology Ningbo 315040China

marine umbilical is one of the key equipment for subsea oil and gas exploitation,which is usually integrated by a great number of different functional components with *** layout of these components directly affects manufacturing,operation and storage performances of the *** the multi-layer cross-sectional layout design of the umbilical,a quantifiable multi-objective optimization model is established according to the operation and storage *** the manufacturing factors,the multi-layering strategy based on contact point identification is introduced for a great number of functional ***,the GA-GLM global optimization algorithm is proposed combining the genetic algorithm and the generalized multiplier method,and the selection operator of the genetic algorithm is improved based on the steepest descent *** algorithm is used to find the optimal solution in the global space,which can converge from any initial layout to the feasible layout *** feasible layout solution is taken as the initial value of the generalized multiplier method for fast and accurate ***,taking umbilicals with a great number of components as examples,the results show that the cross-sectional performance of the umbilical obtained by optimization algorithm is better and the solution efficiency is ***,the multi-layering strategy is effective and *** design method proposed in this paper can quickly obtain the optimal multi-layer cross-sectional layout,which replaces the manual design,and provides useful reference and guidance for the umbilical industry.

关键词： umbilical cross-sectional layout multi-layers GA-GLM optimization

Universal synthesis of metallophthalocyanine covalent organic frameworks as ultra-sensitive multifaceted electrochemical sensor

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Science China Chemistry 2024年第6期67卷 2092-2101页

作者： Qi Liu Qiqi Sun Yuming Zhang Hao Li Wenmiao Chen Yuexing Zhang Sirong Yu Yanli Chen Jianzhuang Jiang School of Materials Science and engineering China University of Petroleum(East China)Qingdao266580China Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials School of Chemistry and Biological EngineeringUniversity of Science and Technology BeijingBeijing100083China college of Chemistry and Chemical engineering Dezhou UniversityDezhou253023China

The universal synthesis of highly stable covalent organic frameworks(COFs)for ultra-sensitive and multi-component electrochemical detection in different scenarios remains a great ***,a series of metallophthalocyanine-based twodimensional(2D)dioxin(DXI)-linked metalophthalocyanine(MPc)-n DXI-COFs(M=Ni,Zn;n=1,2)are afforded in high yield(80%-96%)by a facile trace-quinoline assisted one-pot condensation of tetracarbonitrile *** X-ray diffraction and electron microscopy investigations disclose their lamellar texture 2D network with AA stacking *** and calculation results elucidate that the 2DXI-linked MPc-2DXI-COFs provide the stronger built-in electronic field and more electrostatic/hydrogen bonding adsorption sites than DXI-linked MPc-DXI-COFs,and the lower electrode reaction Gibbs free energy and stronger adsorption of analytes at Ni Pc than Zn Pc unit,which grants Ni Pc-2DXI-COF excellent sensing properties for various analytes including neurotransmitters,organic pollutants,and heavy metal ions,with high sensitivity and low detection limit of 0.53 to 25.66 *** in binary and ternary systems and even in real-world conditions,simultaneous multi-component detection could be achieved.

关键词： covalent organic framework metallophthalocyanine 2D materials electrochemical sensors multi-component detection

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Photoelectrocatalytic hydrogen evolution and synchronous degradation of organic pollutants by pg-C_(3)N_(4)/β-FeOOH S-scheme heterojunction

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Science China(Technological Sciences) 2024年第4期67卷 1238-1252页

作者： LI XiBao HAN Tao ZHOU YingTang XIE Yu LUO YiDan HUANG JunTong CHEN Zhi DENG Fang School of Materials Science and engineering Nanchang Hangkong UniversityNanchang 330063China National-Local Joint engineering Research Center of Heavy Metal Pollutants Control and Resource Utilization Nanchang Hangkong UniversityNanchang 330063China Zhejiang Key Laboratory of Petrochemical Environmental Pollution Control National Engineering Research Center for Marine AquacultureMarine Science and Technology CollegeZhejiang Ocean UniversityZhoushan 316022China

Crafting photoelectrocatalytic materials with robust oxidation-reduction properties for simultaneous hydrogen evolution and pollutant degradation poses a formidable *** this study,a pg-C_(3)N_(4)/β-FeOOH S-scheme heterostructure with a special energy band structure was developed by anchoring porous pg-C_(3)N_(4)on needle shapedβ-*** as a hole extraction layer,needle-leaf-likeβ-FeOOH can facilitate efficient hole migration and enhance charge ***,the optimized 0.2-pg-C_(3)N_(4)/β-FeOOH could degrade 78%of ofloxacin(OFLO)in 90 *** organic pollutants could absorb a large number of holes,which prompted a greater proportion of photogenerated electrons to actively participate in the hydrogen evolution reaction at the ***,the hydrogen production of 0.2-pg-C_(3)N_(4)/β-FeOOH reached 1452.88μmol cm^(-2)h^(-1),exhibiting a notable increase of 61.81-165.12μmol cm^(-2)h^(-1)compared with that in the absence of *** and theoretical calculation results underscore that this investigation is grounded in a distinctive electron and hole dual channel transfer *** findings offer novel insights for the future development of S-scheme heterojunction photoelectrocatalytic materials capable of concurrently degrading pollutants and promoting hydrogen evolution.

关键词： photoelectrocatalysis hydrogen evolution degradation synchronous S-scheme heterojunction

Path-Following Control With Obstacle Avoidance of Autonomous Surface Vehicles Subject to Actuator Faults

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 956-964页

作者： Li-Ying Hao Gege Dong Tieshan Li Zhouhua Peng the School of marine Electrical engineering Dalian Maritime UniversityDalian 116026China the School of Automation engineering University of Electronic Science and Technology of ChinaChengdu 611731the Navigation CollegeDalian Maritime UniversityDalian 116026 the Yangtze Delta Region Institute(Huzhou) Huzhou 313001China

This paper investigates the path-following control problem with obstacle avoidance of autonomous surface vehicles in the presence of actuator faults,uncertainty and external *** surface vehicles inevitably suffer from actuator faults in complex sea environments,which may cause existing obstacle avoidance strategies to *** reduce the influence of actuator faults,an improved artificial potential function is constructed by introducing the lower bound of actuator efficiency *** nonlinear state observer,which only depends on measurable position information of the autonomous surface vehicle,is used to address uncertainties and external *** using a backstepping technique and adaptive mechanism,a path-following control strategy with obstacle avoidance and fault tolerance is designed which can ensure that the tracking errors converge to a small neighborhood of *** with existing results,the proposed control strategy has the capability of obstacle avoidance and fault tolerance ***,the comparison results through simulations are given to verify the effectiveness of the proposed method.

关键词： Actuator faults autonomous surface vehicle(ASVs) improved artificial potential function nonlinear state observer obstacle avoidance

A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

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China Ocean engineering 2024年第2期38卷 233-246页

作者： DING Xin-dong WANG Shu-qing LIU Wen-cheng YE Xiao-han college of engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean engineering Ocean University of ChinaQingdao 266100China Department of marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water *** investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are *** the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary *** for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with *** has been observed that the cross-section of the middle part collapses when it reaches the maximum *** collapse pressure obtained from the numerical simulations agrees well with that in the ***,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also *** has a relatively greater difference because of the ignorance of the progressive failure of *** the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality