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Vibration Control of A Flexible Marine Riser System Subject to Input Dead Zone and Extraneous Disturbances

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China Ocean Engineering 2024年第2期38卷 271-284页

作者： zhou li WANG guo-rong WAN Min School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China Energy Equipment Institute Southwest Petroleum UniversityChengdu 610500China National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China

An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental *** control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control ***,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each *** direction interference observers are designed to track the timevarying boundary *** this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead *** addition,the stability of the closed-loop system is proven by Lyapunov stability *** the system states are bounded,and the vibration offset of the riser converges to a small area of the initial ***,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.

关键词： adaptive backstepping control disturbance observer flexible marine riser input dead zone vibration control

CVTD: A Robust Car-Mounted Video Text Detector

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Computers, Materials & Continua 2024年第2期78卷 1821-1842页

作者： Di zhou Jianxun Zhang Chao li Yifan guo Bowen li Department of Computer Science and Engineering Chongqing University of TechnologyChongqingChina College of Information and Engineering Jingdezhen Ceramic UniversityJingdezhenChina

Text perception is crucial for understanding the semantics of outdoor scenes,making it a key requirement for building intelligent systems for driver assistance or autonomous *** information in car-mounted videos can assist drivers in making ***,Car-mounted video text images pose challenges such as complex backgrounds,small fonts,and the need for real-time *** proposed a robust Car-mounted Video Text Detector(CVTD).It is a lightweight text detection model based on ResNet18 for feature extraction,capable of detecting text in arbitrary *** model efficiently extracted global text positions through the Coordinate Attention Threshold Activation(CATA)and enhanced the representation capability through stacking two Feature Pyramid Enhancement Fusion Modules(FPEFM),strengthening feature representation,and integrating text local features and global position information,reinforcing the representation capability of the CVTD *** enhanced feature maps,when acted upon by Text Activation Maps(TAM),effectively distinguished text foreground from non-text ***,we collected and annotated a dataset containing 2200 images of Car-mounted Video Text(CVT)under various road conditions for training and evaluating our model’s *** further tested our model on four other challenging public natural scene text detection benchmark datasets,demonstrating its strong generalization ability and real-time detection *** model holds potential for practical applications in real-world scenarios.

关键词： Deep learning text detection Car-mounted video text detector intelligent driving assistance arbitrary shape text detector

Mechanical Behavior Based on Aggregates Microstructure of Ultra-high Performance Concrete

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 673-681页

作者：丁庆军 zhou Changsheng 张高展 guo Hong li Yang ZHANG Yongyuan guo Kaizheng School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Advanced Building Materials Key Laboratory of Anhui Province School of Material Science and Chemical EngineeringAnhui Jianzhu UniversityHefei 230601China China Railway 17th Bureau Group Co. Ltd.Taiyuan 030006China

We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for *** properties of compressive strength,elastic modulus,ultrasonic pulse velocity,flexural strength,and toughness were *** electron microscopy and nanoindentation were also conducted to reveal the underlying mechanisms affecting macroscopic *** to the superior interface bonding properties between mullite sand and matrix,the compressive strength and flexural toughness of UHPC have been significantly *** sand and BCS aggregates have higher stiffness than quartz sand,contributing to the excellent elastic modulus exhibited by *** stiffness and volume of aggregates have a more significant impact on the elastic modulus of UHPC than interface performance,and the latter contributes more to the strength of *** study will provide a reference for developing UHPC with superior elastic modulus for structural engineering.

关键词： ultra-high performance concrete mechanical properties fine aggregates microstructure nanoindentation

Co_(3)S_(4)-pyrolysis lotus fiber flexible textile as a hybrid electrocatalyst for overall water splitting

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Journal of Energy Chemistry 2024年第2期89卷 336-344,I0008页

作者： Qiulan zhou Zhen liu Xuxu Wang Yaqian li Xin Qin lijuan guo liwei zhou Weijian Xu Academician Workstation Changsha Medical UniversityChangsha 410219HunanChina College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082HunanChina College of Environmental Science and Engineering Hunan UniversityChangsha 410082HunanChina School of Basic Medicine Changsha Medical UniversityChangsha 410219HunanChina

Electrocatalytic overall water splitting(OWS),a pivotal approach in addressing the global energy crisis,aims to produce hydrogen and ***,most of the catalysts in powder form are adhesively bounding to the electrodes,resulting in catalyst detachment by bubble generation and other uncertain interference,and eventually reducing the OWS *** surmount this challenge,we synthesized a hybrid material of Co_(3)S_(4)-pyrolysis lotus fiber(labeled as Co_(3)S_(4)-p LF)textile by hydrothermal and hightemperature pyrolysis processes for electrocatalytic *** to the natural LF textile exposing the uniformly distributed functional groups(AOH,ANH_(2),etc.)to anchor Co_(3)S_(4)nanoparticles with hierarchical porous structure and outstanding hydrophily,the hybrid Co_(3)S_(4)-p LF catalyst shows low overpotentials at 10 m A cm^(-2)(η_(10,HER)=100 m Vη_(10,OER)=240 mV)alongside prolonged operational stability during electrocatalytic *** calculations reveal that the electron transfer from p LF to Co_(3)S_(4)in the hybrid Co_(3)S_(4)-p LF is beneficial to the electrocatalytic *** work will shed light on the development of nature-inspired carbon-based materials in hybrid electrocatalysts for OWS.

关键词： Overall water splitting Hybrid electrocatalyst Textile Lotus fiber Co_(3)S_(4)nanoparticles

Deep genome skimming reveals the hybrid origin of Pseudosasa gracilis (Poaceae: Bambusoideae)

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Plant Diversity 2024年第3期46卷 344-352页

作者： Xiang-zhou Hu Cen guo Sheng-Yuan Qin De-Zhu li Zhen-Hua guo Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Pseudosasa gracilis(Poaceae:Bambusoideae)is a temperate woody bamboo species endemic to Southcentral China with a narrow *** phylogenetic studies revealed an unexpected,isolated phylogenetic position of *** we conducted phylogenomic analysis by sampling populations of *** and its sympatric species *** and Sinosasa polytricha reflecting different genomic signals,by deep genome *** molecular evidence from chloroplast genes and genome-wide SNPs,we deciphered the phylogenetic relationships of *** plastid and nuclear data indicate that *** is more closely related to Sinosasa,which is discordant with the taxonomic *** further explore this molecular-morphological conflict,we screened 411“perfect-copy”syntenic genes to reconstruct phylogenies using both the concatenation and coalescent *** observed extensive discordance between gene trees and the putative species tree.A significant hybridization event was detected based on 411 genes from the D subgenome,showing *** was a hybrid descendant between Sinosasa longiligulata and ***,with 63.56%and 36.44%inheritance probabilities of each ***,introgression events were detected in the C subgenome between *** and *** in the same distribution *** findings suggest that sympatric hybridization and introgression play a crucial role in the origin of *** providing an empirical example of bamboo of hybrid origin using comprehensive analyses based on genomic data from different inheritance systems and morphological characters,our study represents a step forward in understanding of reticulate evolution of bamboos.

关键词： Phylogenomics Hybridization Introgression Pseudosasa gracilis Pseudosasa Sinosasa

Microstructure Modification and Ductility Improvement for TaMoNbZrTiAl Refractory High Entropy Alloys via Increasing Ti Content

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1186-1200页

作者： Yujing zhou Siyi Peng Yueling guo Xiaoxiang Wu Changmeng liu Zhiming li School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China Shagang School of Iron and Steel Soochow UniversitySuzhou215137China School of Materials Science and Engineering Central South UniversityChangsha410083China

Here, the composition of TaMoNbZrTiAl refractory high entropy alloy (RHEA) is optimized by increasing Ti content to improve its mechanical property especially the ductility, through comparing two RHEAs with different Ti content. The RHEAs contain two body-centered-cubic (BCC) phases. The BCC phase in the dendritic region is rich in Ta, Mo and Nb, and the BCC phase in the interdendritic region is enriched in Zr, Ti and Al. The as-cast RHEA with a higher Ti content remains dendritic microstructures, and Ti is mainly enriched in the interdendritic region. After annealing treatment at 1300 ℃ for 48 h, the dendritic microstructures change into equiaxed-grain morphology, accompanied by needle-like micron precipitates at grain boundaries in the RHEA with higher Ti content. For the as-cast RHEAs, the fracture strain increases by ~ 6.6% and the uniform plastic strain increases by ~ 5.9% at the compression test due to the increase of Ti content. Our work offers a reference for the composition design of RHEAs and makes a preliminary exploration of the optimization of the microstructures and mechanical properties.

关键词： Refractory high entropy alloys Solidification Grain morphology Microstructure Mechanical property

Structural properties of residual carbon in coal gasification fine slag and their influence on flotation separation and resource utilization:A review

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 217-230页

作者： Rui Han Anning zhou Ningning Zhang Kaiqiang guo Mengyan Cheng Heng Chen Cuicui li College of Chemistry and Chemical Engineering Xi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Coal Resources Exploration and Comprehensive Utilization Ministry of Natural Resources of ChinaXi’an 710021China

Coal gasification fine slag(FS)is a typical solid waste generated in coal *** current disposal methods of stockpil-ing and landfilling have caused serious soil and ecological *** recovery and the high-value utilization of residual carbon(RC)in FS are the keys to realizing the win-win situation of the coal chemical industry in terms of economic and environmental *** structural properties,such as pore,surface functional group,and microcrystalline structures,of RC in FS(FS-RC)not only affect the flotation recovery efficiency of FS-RC but also form the basis for the high-value utilization of *** this paper,the characteristics of FS-RC in terms of pore structure,surface functional groups,and microcrystalline structure are sorted out in accordance with gasification type and FS particle *** reasons for the formation of the special structural properties of FS-RC are analyzed,and their influence on the flotation separation and high-value utilization of FS-RC is *** methods based on the pore structural characterist-ics of FS-RC,such as ultrasonic pretreatment-pore-blocking flotation and pore breaking-flocculation flotation,are proposed to be the key development technologies for improving FS-RC recovery in the *** design of low-cost,low-dose collectors containing polar bonds based on the surface and microcrystalline structures of FS-RC is proposed to be an important breakthrough point for strengthening the flotation efficiency of FS-RC in the *** high-value utilization of FS should be based on the physicochemical structural proper-ties of FS-RC and should focus on the environmental impact of hazardous elements and the recyclability of chemical waste liquid to es-tablish an environmentally friendly utilization *** review is of great theoretical importance for the comprehensive understand-ing of the unique structural properties of FS-RC,the breakthrough of the technological bottleneck in the e

关键词： coal gasification fine slag residual carbon pore structure surface functional groups microcrystalline structure flotation sep-aration resource utilization

Phosphorous-doped carbon nanotube/reduced graphene oxide aerogel cathode enabled by pseudocapacitance for high energy and power zinc-ion hybrid capacitors

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Chinese Chemical Letters 2024年第2期35卷 570-576页

作者： Junjun Yao Fuzhi li Ruyi zhou Chenchen guo Xinru liu Yirong Zhu Hunan Key Laboratory of Green Metallurgy and New Energy Materials College of Materials and Advanced ManufacturingHunan University of TechnologyZhuzhou 412007China College of packaging and Material Engineering Hunan University of TechnologyZhuzhou 412007China

The design and development of energy storage device with high energy/power density has become a research ***-ion hybrid capacitors(ZHCs)are considered as one of the most promising ***,the application of ZHCs is hindered by their low energy density at high power density due to the unsatisfactory cathode *** this study,a novel 3D phosphorus-doped carbon nanotube/reduced graphene oxide(P-CNT/rGO)aerogel cathode is synthesized through a synergistic modification strategy of CNT insertion and P doping modification combined with 3D porous *** as-obtained P-CNT/rGO aerogel cathode manifests significantly increased surface aera,expanded interlayer spacing,and enhanced pseudocapacitance behavior,thus leading to significantly enhanced specific capacitance and superb ions transport *** as-assembled ZHC based on P-CNT/rGO cathode delivers a superior energy density of 42.2 Wh/kg at an extreme-high power density of 80 kW/kg and excellent cycle ***-depth kinetic analyses are undertaken to prove the enhanced pseudocapacitance behavior and exceptional power output capability of ***,the reaction mechanism of physical and chemical adsorption/desorption of electrolyte ions on the P-CNT/rGO cathode is revealed by systematic ex-situ *** work can provide a valuable reference for developing advanced graphene-based cathode for high energy/power density ZHCs.

关键词： Graphene aerogel Phosphorus doping Pseudocapacitance Zinc-ion hybrid capacitors Energy storage mechanism

Two-dimensional silica enhanced solid polymer electrolyte for lithium metal batteries

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Particuology 2024年第2期85卷 146-154页

作者： Zhihong Luo Weiyong li Chong guo Ya Song Mingxia zhou Yan Shi Jing Xu Long li Bin Shi Quansheng Ouyang Jiao-jing Shao Guangmin zhou School of Materials and Metallurgy Guizhou UniversityGuiyang550025China State Key Laboratory of Advanced Chemical Power Sources Zunyi563003China Graphene Materials Engineering Research Center of Guizhou Colleges and Universities Guiyang550025China Tsinghua-Berkeley Shenzhen Institute&Tsinghua Shenzhen International Graduate Schoo Tsinghua UniversityShenzhen518055China

Solid polymer electrolytes(SPEs)are promising substitutes for current flammable liquid electrolytes to achieve high-safety and high-energy-density lithium metal *** oxide(PEO)based solid polymer electrolytes have attracted increasing attention because of their excellent flexibility,manufacturability,light weight,and low-cost processing,while they often suffer from low ionic con-ductivity at room temperature,low lithium transference number and unsatisfactory interfacial resis-tance,which largely restrain their practical ***,two-dimensional holey silica nanosheets(2D-HSN)as the fillers,together with liNO_(3) as the electrolyte additive,are introduced in a PEO/poly(-vinylidene fiuoride-co-hexafluoropropylene)(PVDF-HFP)blended polymer matrix to obtain a *** incorporation of HSN filler creates supplementary channels for lithium ion migration and lowers the crystallinity of the polymer,thereby facilitating the movement of lithium *** HSN-based SPE demonstrates higher ionic conductivity up to 3.7 x 10-4 S cm-1 at 30℃,larger li+transference number close to 0.34,and more stable lithium plating/stripping than that without the fillers,and HSN can promote the formation of more stable solid electrolyte interphase(SEI)*** as-assembled liFePO4||li batteries deliver a high specific capacity of 159 mA h g-1 with the capacity retention of 95.5%after 200 cycles at 30℃,as well as superior rate performance and cycling stability compared to that using the blank SPE.

关键词： Vermiculite nanosheets Two-dimensional silica Solid polymer electrolytes Fillerslithium metal batteries