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Journal of Environmental Sciences 2024年第5期139卷 543-555页

作者： Kai Xu Yunyu Guo Chenghua Xing Ronglong Fu Bin Zou Rongchuan Liu Luyi Cai Jianfang Yan Xi-Lin Wu Miaozhen Cai college of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua 321004China college of Agriculture Jinhua PolytechnicJinhua 321007China

Cadmium(Cd)pollution poses a serious threat to plant growth and *** have shown great application potential for alleviation of Cd toxicity to *** this study,we applied graphitic carbon nitride nanosheets(g-C_(3)N_(4)NSs)for alleviation of Cd-toxicity to soybean(Glycine max L.).The g-C_(3)N_(4)NSs supplementation significantly improved plant growth and reduced oxidative damage in the Cd-toxicated soybean seedlings through hydroponic ***,the g-C_(3)N_(4)NSs dynamically regulated the root cell wall(RCW)components by increasing pectin content and modifying its demethylation via enhancing pectin methylesterase(PME)activity,therefore greatly enhanced stronger RCW-Cd retention(up to 82.8%)and reduced Cd migration to the ***,the g-C_(3)N_(4)NSs reversed the Cd-induced chlorosis,increased photosynthetic efficiency because of enhancement in F_v/F_mration,Y(Ⅱ)and sugars *** results provide new insights into the alleviation of Cd toxicity to plants by g-C_(3)N_(4)NSs,and shed light on the application of low-cost and environmental-friendly carbon-based NMs for alleviating heavy metal toxicity to plants.

关键词： Cadmium Carbon nitride nanosheets Cell wall Pectin Pectin methylesterase Soybean

An Underwater Target Detection Algorithm Based on Attention Mechanism and Improved YOLOv7

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Computers, Materials & Continua 2024年第2期78卷 2829-2845页

作者： Liqiu Ren Zhanying Li Xueyu He Lingyan Kong Yinghao Zhang college of Information Science and Engineering Dalian Polytechnic UniversityDalian116034China

For underwater robots in the process of performing target detection tasks,the color distortion and the uneven quality of underwater images lead to great difficulties in the feature extraction process of the model,which is prone to issues like error detection,omission detection,and poor ***,this paper proposed the CER-YOLOv7(CBAM-EIOU-RepVGG-YOLOv7)underwater target detection *** improve the algorithm’s capability to retain valid features from both spatial and channel perspectives during the feature extraction phase,we have added a Convolutional Block Attention Module(CBAM)to the backbone *** Reparameterization Visual Geometry Group(RepVGG)module is inserted into the backbone to improve the training and inference *** Efficient Intersection over Union(EIoU)loss is also used as the localization loss function,which reduces the error detection rate and missed detection rate of the *** experimental results of the CER-YOLOv7 algorithm on the UPRC(Underwater Robot Prototype Competition)dataset show that the mAP(mean Average Precision)score of the algorithm is 86.1%,which is a 2.2%improvement compared to the *** feasibility and validity of the CER-YOLOv7 are proved through ablation and comparison experiments,and it is more suitable for underwater target detection.

关键词： Deep learning underwater object detection improved YOLOv7 attention mechanism

Examining the Use of Scott’s Formula and Link Expiration Time Metric for Vehicular Clustering

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2421-2444页

作者： Fady Samann Shavan Askar Department of Energy Engineering Technical College of EngineeringDuhok Polytechnic UniversityDuhok42001Iraq Department of Information System Engineering Technical College of EngineeringErbil Polytechnic UniversityErbil44001Iraq

Implementing machine learning algorithms in the non-conducive environment of the vehicular network requires some adaptations due to the high computational complexity of these algorithms.K-clustering algorithms are simplistic,with fast performance and relative ***,their implementation depends on the initial selection of clusters number(K),the initial clusters’centers,and the clustering *** paper investigated using Scott’s histogram formula to estimate the K number and the Link Expiration Time(LET)as a clustering *** traffic flows were considered for three maps,namely Highway,Traffic Light junction,and Roundabout junction,to study the effect of road layout on estimating the K number.A fast version of the PAM algorithm was used for clustering with a modification to reduce time *** Affinity propagation algorithm sets the baseline for the estimated K number,and the Medoid Silhouette method is used to quantify the ***++,Veins,and SUMO were used to simulate the traffic,while the related algorithms were implemented in *** Scott’s formula estimation of the K number only matched the baseline when the road layout was ***,the clustering algorithm required one iteration on average to converge when used with LET.

关键词： Clustering vehicular network Scott’s formula FastPAM

Repair of Second-Generation Recycled Fine Aggregate of Waste Concrete from Freeze-Thaw Environment by Carbonation Treatment

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Journal of Renewable Materials 2024年第1期12卷 187-201页

作者： Jie Huang Rongbin Jiang Xiaobo Sun Yingyong Shuai School of Building Engineering Taizhou Polytechnic CollegeTaizhou225300China

The reuse of waste recycled concrete from harsh environments has become a research hotspot in the field of *** study investigated the repair effect of carbonation treatment on second-generation recycled fine aggregate(SRFA)obtained from recycled fine aggregate concrete(RFAC)subjected to freeze-thaw(FT)*** and after carbonation,the properties of SRFA were *** second-generation recycled fine aggregate(CSRFA)at five substitution rates(0%,25%,50%,75%,100%)to replace SRFA was used to prepare carbonated second-generation recycled fine aggregate concrete(CSRFAC).The water absorption,porosity and mechanical properties of CSRFAC were tested,and its frost-resisting durability was *** results showed after carbonation treatment,the physical properties of SRFA was improved and met the requirements of II *** micro-hardness of the interfacial transition zone and attached mortar in CSRFA was 50.5%and 31.2%higher than that in SRFA,*** the increase of CSRFA replacement rate,the water absorption and porosity of CSRFAC gradually decreased,and the mechanical properties and frost resistance of CSRFAC were gradually *** treatment effectively repairs the damage of SRFA caused by FT cycles and improves its application potential.

关键词： Carbonation treatment repair freeze-thaw cycles second-generation recycled fine aggregate

Effects of zeolite imidazole frameworks on rice seedlings (Oryza sativa L.): Phytotoxicity, transformation, and bioaccumulation

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Journal of Environmental Sciences 2024年第10期144卷 15-25页

作者： Chaofa Chen Yongqi Yao Chenghua Xing Yunyu Guo Luyi Cai Jianfang Yan Xi-Lin Wu Miaozhen Cai college of Geography and Environmental Science Zhejiang Normal UniversityJinhuaZhejiang 321004China college of Agriculture Jinhua PolytechnicJinhuaZhejiang 321007China

Zeolite imidazole frameworks(ZIFs),a class of the metal organic framework,have been extensively studied in environmental ***,their environmental fate and potential ecological impact on plants remain ***,we investigated the phytotoxicity,transformation,and bioaccumulation processes of two typical ZIFs(ZIF-8 and ZIF-67)in rice(Oryza sativa L.)under hydroponic ***-8 and ZIF-67 in the concentration of 50 mg/L decreased root and shoot dry weight maximally by 55.2%and 27.5%,53.5%and 37.5%,*** scanning electron microscopy(SEM)imaging combined with X-ray diffraction(XRD)patterns revealed that ZIFs on the root surface gradually collapsed and transformed into nanosheets with increasing cultivation *** fluorescein isothiocyanate(FITC)labeled ZIFs were applied to trace the uptake and translocation of ZIFs in *** results demonstrated that the transformed ZIFs were mainly distributed in the intercellular spaces of rice root,while they cannot be transported to culms and *** so,the Co and Zn contents of rice roots and shoots in the ZIFs treated groups were increased by 1145%and 1259%,145%and 259%,respectively,compared with the control *** findings suggested that the phytotoxicity of ZIFs are primarily attributed to the transformed ZIFs and to a less extent,the metal ions and their ligands,and they were internalized by rice root and increased the Co and Zn contents of *** study reported the transformation of ZIFs and their biological effectiveness in rice,highlighting the potential environmental hazards and risks of ZIFs to crop plants.

关键词： Zeolitic imidazolate frameworks (ZIFs) Rice(Oryza sativa L.) Phytotoxicity Transformed ZIFs ZIFs bioaccumulation

Mechanical Property and Microstructure of Cement Mortar with Carbonated Recycled Powder

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 689-697页

作者：丁亚红张美香 YANG Xiaolin XU Ping SUN Bo GUO Shuqi Department of Civil Engineering Henan Polytechnic UniversityJiaozuo 454150China college of Architectural Engineering Xinyu UniversityXinyu 336500China

Carbonated recycled powder as cementitious auxiliary material can reduce carbon emissions and realize high-quality recycling of recycled *** this paper,microscopic property of recycled powder with three carbonation methods was tested through XRD and SEM,the mechanical property and microstructure of recycled powder mortar with three replacement rates were studied by ISO method and SEM,and the strengthening mechanism was *** results showed that the mechanical property of recycled powder mortar decreased with the increasing of replacement *** is suggested that the replacement rate of recycled powder should not exceed 20%.The strength index and activity index of carbonated recycled powder mortar were improved,in which the flexural strength was increased by 27.85%and compressive strength was increased by 20%at the *** powder can be quickly and completely carbonated,and the improvement effect of CH pre-soaking carbonation was the *** activity index of carbonated recycled powder can meet the requirements of Grade II technical standard for recycled *** results revealed the activation mechanism of carbonated recycled powder such as surplus calcium source effect,alkaline polycondensation effect and carbonation enhancement effect.

关键词： recycled powder carbonation activation compound carbonation activity index mechanical property microstructure

High-efficiency Carbonation Modification Methods of Recycled Coarse Aggregates

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 386-398页

作者：张美香 YANG Xiaolin 丁亚红 SUN Bo ZHANG Xianggang LÜXiuwen Department of Civil Engineering Henan Polytechnic UniversityJiaozuo 454150China college of Architectural Engineering Xinyu UniversityXinyu 336500China

To solve the problem of only surface carbonation and realize high-efficiency carbonation of recycled coarse aggregate,the method of carbonated recycled coarse aggregate with nano materials pre-soaking was first put *** carbonation effect of modified recycled coarse aggregate with three different carbonation methods was evaluated,and water absorption,apparent density and crush index of modified recycled coarse aggregate were *** with XRD,SEM,and MIP microscopic analysis,the high-efficiency carbonation strengthening mechanism of modified recycled coarse aggregate was *** experimental results show that,compared with the non-carbonated recycled coarse aggregate,the physical and microscopic properties of carbonated recycled coarse aggregate are *** method of carbonation with nano-SiO_(2) pre-soaking can realize the high-efficiency carbonation of recycled coarse aggregate,for modified recycled coarse aggregate with the method,water absorption is reduced by 23.03%,porosity is reduced by 44.06%,and the average pore diameter is 21.82 *** high-efficiency carbonation strengthening mechanism show that the pre-socked nano-SiO_(2) is bound to the hydration product Ca(OH)_(2) of the old mortar with nano-scale C-S-H,which can improve the CO_(2) absorption rate,accelerate the carbonation reaction,generate more stable CaCO_(3) and nano-scale silica gel,and bond to the dense three-dimensional network structure to realize the bidirectional enhancement of nano-materials and pressurized *** is concluded that the method of carbonation with nano-SiO_(2) pre-soaking is a novel high-efficiency carbonation modification of recycled coarse aggregate.

关键词： recycled coarse aggregate pressurized carbonation high-efficiency carbonation nano-SiO2 strengthening mechanism

Adaptive state-constrained/model-free iterative sliding mode control for aerial robot trajectory tracking

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 603-618页

作者： Chen AN Jiaxi ZHOU Kai WANG college of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina

This paper develops a novel hierarchical control strategy for improving the trajectory tracking capability of aerial robots under parameter *** hierarchical control strategy is composed of an adaptive sliding mode controller and a model-free iterative sliding mode controller(MFISMC).A position controller is designed based on adaptive sliding mode control(SMC)to safely drive the aerial robot and ensure fast state convergence under external ***,the MFISMC acts as an attitude controller to estimate the unmodeled dynamics without detailed knowledge of aerial ***,the adaption laws are derived with the Lyapunov theory to guarantee the asymptotic tracking of the system ***,to demonstrate the performance and robustness of the proposed control strategy,numerical simulations are carried out,which are also compared with other conventional strategies,such as proportional-integralderivative(PID),backstepping(BS),and *** simulation results indicate that the proposed hierarchical control strategy can fulfill zero steady-state error and achieve faster convergence compared with conventional strategies.

关键词： aerial robot hierarchical control strategy model-free iterative sliding mode controller(MFISMC) trajectory tracking reinforcement learning

Mechanism in Solidification of a Ternary Nickel Based Alloy

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 1018-1024页

作者：田密成博 School of Aeronautical Manufacturing Industry Chengdu Aeronautical PolytechnicChengdu 610100China college of Mechanical Engineering North University of ChinaTaiyuan 030051China

The experiment employed the use of melt purification and cyclic superheating technique to achieve maximum undercooling of Ni65Cu31Co4 alloy at ***,high-speed photography techniques were used to capture the process of alloy liquid phase interface migration,and analyzed the relationship between the shape characteristics of the front end of alloy solidification and *** microstructure of the alloy was observed through metallographic microscopy,and the micro-morphological characteristics and evolution of the rapidly solidified microstructure were systematically *** is found that the grain refinement mechanism of Ni-Cu-Co ternary alloy is similar to that of Ni-Cu binary *** refinement at low undercooling is caused by intense dendritic remelting,while grain refinement at high undercooling is attributed to recrystallization,driven by the stress and plastic strain accumulated from the interaction of liquid flow and primary dendrites caused by rapid *** also shows that the addition of the third element Co plays a significant role in solidification rate and re-ignition effect.

关键词： undercooling recalescence Ni-Cu-Co ternary alloy grain refinement recrystallization

Towards Data-Driving Multi-View Evaluation Framework for Scratch

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Tsinghua Science and Technology 2024年第2期29卷 517-528页

作者： Xiaolin Chai Yan Sun Yan Gao Department of Computer Science Beijing University of Posts and TelecommunicationBeijing 100876China Intellectual Property Institute Shandong Polytechnic CollegeJining 272067China

As one of the most popular visual programming languages,Scratch has a lot of evaluation around *** evaluation can help programmers understand their projects *** the same time,it can also provide a reference for them to browse other projects in the online *** of the existing evaluations on Scratch are carried from three perspectives:Computational Thinking(CT)ability,visual presentation aesthetics,and code *** them,the assessment of CT and code quality is mainly carried out from the program script,while the evaluation of visual aesthetics is analyzed from the perspective of image sequences generated by project *** single-view evaluation focuses on the performance of a program in a certain aspect and is *** this paper,we propose a multi-view evaluation framework to integrate various evaluations using different *** quantitatively analyze the assessment of different views driven by *** with overall evaluations that represent human opinions,we analyze their differences and *** experiments,we determine the weights of different integration policies,the proposed multi-view evaluation method can generate evaluation results similar to human opinions.

关键词： Scratch Computational Thinking(CT) visual aesthetic static analysis integration policy machine learning