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High-Performance Recyclable Furan-based Epoxy Resin and Its Carbon Fiber Composites with Dense Hydrogen Bonding

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Chinese Journal of Polymer Science 2024年第1期42卷 73-86,I0008页

作者： chang-Bo Zhao Lu-Kun Feng Hui Xie Ming-Liang wang Bing Guo Zhi-Yong Xue Cai-zhen Zhu Jian Xu Advanced Materials Research Institute North China Electric Power UniversityBejing 102206China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology and Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive ApplicationHarbin Institute of TechnologyShenzhen 518055China

The emerging biomass-based epoxy vitrimers hold great potential to fulfill the requirements for sustainable development of *** the existence of dynamic chemical bonds in vitrimers often reduces both the thermal and mechanical properties of epoxy resins, it is challenging to produce recyclable epoxy vitrimers with both excellent mechanical properties and good thermal stability. Herein, a monomer 4-(((5-(hydroxymethyl)furan-2-yl)methylene)amino)phenol(FCN) containing furan ring with potential to form high density of hydrogen bonding among repeating units is designed and copolymerized with glycerol triglycidyl ether to yield epoxy resin(FCN-GTE), which intrinsically has dual hydrogen bond networks, dynamic imine structure and resultant high performance. Importantly, as compared to the BPA-GTE, the FCN-GTE exhibits significantly improved mechanical properties owing to the increased density of hydrogen bond network and physical crosslinking interaction. Furthermore, density functional theory(DFT) calculation and in situ FTIR analysis is conducted to decipher the formation mechanism of hydrogen bond network. In addition, the FCN-GTE possesses superior UV shielding, chemical degradation, and recyclability because of the existence of abundant imine bonds. Notably, the FCN-GTE-based carbon fiber composites could be completely recycled in an amine *** study provides a facile strategy for synthesizing recyclable biomass-based high-performance epoxy vitrimers and carbon fiber composites.

关键词： Furan Hydrogen bond network Dynamic Schiff base Carbon fiber composites Recycling

Decentralized Primary Frequency Regulation for Hybrid Multi-terminal Direct Current Power Systems Considering Multi-source Enhancement

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 958-970页

作者： Jialiang Wu zhen wang Ruixu Liu Yu Shan Chenxuan wang the College of Electrical Engineering Zhejiang UniversityHangzhou 310027China the Economic Research Institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310016China

Hybrid multi-terminal direct current(MTDC)transmission technology has been a research focus,and primary frequency regulation(FR)improvement in the receiving-end system is one of the problems to be *** paper presents a decentralized primary FR scheme for hybrid MTDC power systems considering multi-source enhancement to help suppress frequency disturbance in the receiving-end *** the converters only need local frequency or DC voltage signal input to respond to system disturbance without communication or a control center,i.e.,a decentralized control *** proposed scheme can activate appropriate power sources to assist in FR in various system disturbance severities with fine-designed thresholds,ensuring sufficient utilization of each power *** better balance FR performance and FR resource participation,an evaluation index is proposed and the parameter optimization problem is further ***,the validity of the proposed scheme is verified by simulations in MATLAB/Simulink.

关键词： Decentralized control scheme primary frequency regulation(FR) rate of change of frequency(ROCOF) system frequency disturbance

Partition-based Network Equivalent Method for Power System Subsynchronous Oscillation Analysis

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 313-320页

作者： Chenxuan wang Weimin zheng zhen wang Yangqing Dan Ping Ju the Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China the Economic Research Institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310016China the College of Energy and Electrical Engineering Hohai UniverstiyNanjing 211100China

Given large-scale modern power systems with pow er electronic converters,the numerical simulation with subsyn chronous oscillation(SSO)faces great challenges in engineering practice due to sharply enlarged modeling scale and high com putational *** reduce the modeling scale,network parti tion and equivalent becomes a vital technique in numerical sim *** several methods have been developed for net work equivalent,a generally accepted rule for network parti tion is still *** paper proposes that the system can be partitioned into three parts,i.e.,the internal,the middle,and the external subsystems,in which the internal subsystem consists of all power electronic components,the middle subsys tem includes those selected AC dynamic components with de tailed models,and the remaining components and buses consti tute the external *** external subsystem is further represented by an equivalent RLC network determined by the frequency dependent network equivalent(FDNE)*** the proposed method,the observability index and the electrical distance index are used to identify the interface between the middle and the external *** studies based on a modified Hydro-Quebec system are used to verify the effective ness of the proposed method.

关键词： Electrical distance network equivalent subsyn chronous oscillation observability index

∞-Tilting Subcategories in Extriangulated Categories

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 151-160页

作者： zhen ZHANG Jiaqun WEI Shance wang Department of Mathematics Qilu Normal UniversityJinan 250200China Institution of Mathematics School of Mathematics ScienceNanjing Normal UniversityNanjing 210023China

In this paper, the authors introduce a new definition of ∞-tilting(resp. cotilting) subcategories with infinite projective dimensions(resp. injective dimensions) in an extriangulated category. They give a Bazzoni characterization of ∞-tilting(resp. cotilting)subcategories. Also, they obtain a partial Auslander-Reiten correspondence between ∞-tilting(resp. cotilting) subcategories and coresolving(resp. resolving) subcategories with an E-projective generator(resp. E-injective cogenerator) in an extriangulated category.

关键词： Extriangulated category ∞-Tilting subcategory Auslander-Reiten correspondence Bazzoni characterization

Molecular crowding electrolytes for stabilizing Zn metal anode in rechargeable aqueous batteries

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Chinese Chemical Letters 2024年第7期35卷 445-451页

作者： Li Lin Song-Lin Tian zhen-Yu Hu Yu Zhang Li-Min chang Jia-Jun wang Wan-Qiang Liu Qing-Shuang wang Fang wang School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China School of Life Science and Technology Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Preparation and Applications of Environmental Friendly Materials of the Ministry of Education Jilin Normal UniversityChangchun 130103China Zhongshan Institute of changchun University of Science and Technology Zhongshan 528437China

A solid electrolyte interphase(SEI)with a robust mechanical property and a high ionic conductivity is imperative for high-performance zinc metal ***,it is difficult to form such a SEI directly from an *** this work,a molecular crowding effect is based on the introduction of Zn(OTF)_(2)and Zn(ClO_(4))_(2)to 2 mol/L ZnSO_(4)*** and experiments indicate that the Zn(OTF)_(2)and Zn(ClO_(4))_(2)not only create a molecularly crowded electrolyte environment to promote the interaction of Zn^(2+)and OTF^(-),but also participate in the reduction to construct a robust and high ionic-conductive SEI,thus promoting metal zinc deposition to the(002)crystal *** this molecular crowding electrolyte,a high current density of 1 mA/cm^(2)can be obtained by assembling symmetric batteries with Zn as the anode for over 1000 *** in a temperature environment of-10℃,a current density of 1 mA/cm^(2)can be obtained by assembling symmetric batteries with Zn for over 200 ***//Bi_(2)S_(3)/VS4@C cells achieve a CE rate of up to 99.81%over 1000 ***,the utilization of a molecular crowding electrolyte is deemed a highly effective approach to fabricating a sophisticated SEI for a zinc anode.

关键词： Zinc ion batteries Anode Electrolyte Solid electrolyte interphase Molecular crowding effect

Bone remodeling in sigmoid sinus diverticulum after stenting for transverse sinus stenosis in pulsatile tinnitus: A case report

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World Journal of Clinical Cases 2021年第10期9卷 2320-2325页

作者： Xiao-Yu Qiu Peng-Fei Zhao He-Yu Ding Xiao-Shuai Li Han Lv zheng-Han Yang Shu-Sheng Gong Long Jin zhen-chang wang Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Otolaryngology-Head&Neck Surgery Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Interventional Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

BACKGROUND Pulsatile tinnitus(PT)is a potentially disabling symptom that has received increasing *** causes of PT have been confirmed by targeted ***,dynamic changes of related structures in PT patients with multiple causes after stenting for ipsilateral transverse sinus stenosis(TSS)have not been previously *** report such a case and present postoperative computed tomography venography(CTV)follow-up findings to demonstrate the decreased sigmoid sinus diverticulum and bone *** SUMMARY A 45-year-old man suffered from left-sided PT for 15 years that was occasionally accompanied by headache and ***-operative CTV revealed left-sided sigmoid sinus wall anomalies(SSWAs),TSS,outflow dominance,large posterior condylar emissary vein,and an empty sella turcica.A cerebrospinal fluid pressure of 270 mmH2O was further *** sound disappeared immediately after stenting for ipsilateral TSS,with no recurrence during 2 years of *** the procedure,the patient underwent four consecutive CTV *** diverticulum decreased 6 mo after the procedure with new bone *** density of the remodeled bone was further increased 1 year later,and a hardened edge was formed 2 years *** PT associated with SSWAs,TSS,and idiopathic intracranial hypertension can be cured by stenting for TSS *** bone remodeling around SSWAs is a more significant finding.

Ensemble successor representations for task generalization in offline-to-online reinforcement learning

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Science China(Information Sciences) 2024年第7期67卷 240-255页

作者： changhong wang Xudong YU Chenjia BAI Qiaosheng ZHANG zhen wang Space Control and Inertial Technology Research Center Harbin Institute of Technology Shanghai Artificial Intelligence Laboratory Shenzhen Research Institute of Northwestern Polytechnical University School of Cybersecurity Northwestern Polytechnical University

In reinforcement learning(RL), training a policy from scratch with online experiences can be inefficient because of the difficulties in exploration. Recently, offline RL provides a promising solution by giving an initialized offline policy, which can be refined through online interactions. However, existing approaches primarily perform offline and online learning in the same task, without considering the task generalization problem in offline-to-online adaptation. In real-world applications, it is common that we only have an offline dataset from a specific task while aiming for fast online-adaptation for several tasks. To address this problem, our work builds upon the investigation of successor representations for task generalization in online RL and extends the framework to incorporate offline-to-online learning. We demonstrate that the conventional paradigm using successor features cannot effectively utilize offline data and improve the performance for the new task by online fine-tuning. To mitigate this, we introduce a novel methodology that leverages offline data to acquire an ensemble of successor representations and subsequently constructs ensemble Q functions. This approach enables robust representation learning from datasets with different coverage and facilitates fast adaption of Q functions towards new tasks during the online fine-tuning *** empirical evaluations provide compelling evidence showcasing the superior performance of our method in generalizing to diverse or even unseen tasks.

关键词： offline reinforcement learning online fine-tuning task generalization successor representations ensembles

Fe/S oxidation-coupled arsenic speciation transformation mediated by AMD enrichment culture under different pH conditions

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Journal of Environmental Sciences 2024年第3期137卷 681-700页

作者： Yu-hang Zhou Wei-xi Huang zhen-yuan Nie Hong-chang Liu Yue Liu Can wang Jin-lan Xia Wen-sheng Shu Key Lab of Biometallurgy of Ministry of Education of China School of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China School of Life Sciences South China Normal UniversityGuangzhou 510631China

Arsenic(As)speciation transformation in acid mine drainage(AMD)is comprehensively affected by biological and abiotic factors,such as microbially mediated Fe/S redox reactions and changes in environmental conditions(pH and oxidation-reduction potential).However,their combined impacts on arsenic speciation transformation remain poorly ***,we explored arsenic transformation and immobilization during pyrite dissolution mediated by AMD enrichment culture under different acidic pH *** results for incubation and mineralogical transformation of solid residues show that in the presence of AMD enrichment culture,pH 2.0,2.5,and 3.0 are more conducive to the formation of jarosites and ferric arsenate,which could immobilize high quantities of dissolved arsenic by adsorption and *** pH conditions significantly affect the initial adsorption of microbial cells to the minerals and the evolution of microbial community structure,further infuencing the biodissolution of pyrite and the release and oxidation process of Fe/*** results of Fe/S/As speciation transformation of the solid residues show that the transformation of Fe,S,and As in solution is mainly regulated by pH and potential values,which imposed significantly different effects on the formation of secondary minerals and thus arsenic oxidation and *** above results indicated that arsenic transformation is closely related to the Fe/S oxidation associated with pyrite bio-oxidation,and this correlation is critically regulated by the pH conditions of the system.

关键词： Acid mine drainage(AMD) pH conditions Fe/S/As speciation transformation Microbial community structure

A New Industrial Intrusion Detection Method Based on CNN-BiLSTM

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Computers, Materials & Continua 2024年第6期79卷 4297-4318页

作者： Jun wang changfu Si zhen wang Qiang Fu College of Computer Science and Technology Shenyang University of Chemical TechnologyShenyang110142China

Nowadays,with the rapid development of industrial Internet technology,on the one hand,advanced industrial control systems(ICS)have improved industrial production ***,there are more and more cyber-attacks targeting industrial control *** ensure the security of industrial networks,intrusion detection systems have been widely used in industrial control systems,and deep neural networks have always been an effective method for identifying cyber *** intrusion detection methods still suffer from low accuracy and a high false alarm ***,it is important to build a more efficient intrusion detection *** paper proposes a hybrid deep learning intrusion detection method based on convolutional neural networks and bidirectional long short-term memory neural networks(CNN-BiLSTM).To address the issue of imbalanced data within the dataset and improve the model’s detection capabilities,the Synthetic Minority Over-sampling Technique-Edited Nearest Neighbors(SMOTE-ENN)algorithm is applied in the preprocessing *** algorithm is employed to generate synthetic instances for the minority class,simultaneously mitigating the impact of noise in the majority *** approach aims to create a more equitable distribution of classes,thereby enhancing the model’s ability to effectively identify patterns in both minority and majority *** the experimental phase,the detection performance of the method is verified using two data *** results show that the accuracy rate on the CICIDS-2017 data set reaches 97.7%.On the natural gas pipeline dataset collected by Lan Turnipseed from Mississippi State University in the United States,the accuracy rate also reaches 85.5%.

关键词： Intrusion detection convolutional neural network bidirectional long short-term memory neural network multi-head self-attention mechanism