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Synthesis and Properties of Photodegradable Poly(furan-amine)s by a Catalyst-free Multicomponent Cyclopolymerization

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Chinese Journal of Polymer Science 2019年第10期37卷 981-989,I0004页

作者： wei-qiang fu Gui-Nan Zhu Jian-Bing Shi Bin Tong Zheng-Xu Cai Yu-Ping Dong Beijing Key Laboratory of Construction Tailorable Advanced functional Materials and Green Applications School of Materials Science and EngineeringBeijing Institute of Technology

A series of new photodegradable poly(furan-amine)s(PFAs) were synthesized by a one-pot, catalyst-free, multicomponent cyclopolymerization between diisocyanides, dialkylacetylene dicarboxylates, and aromatic dialdehydes. All polymerizations were conducted in toluene at 100 ℃ for 6 h without inert gas protection and furnished polymers with a satisfactory molecular weight(Mw up to32200) and yield. The PFA structure was confirmed by spectroscopic techniques, such as GPC, FTIR, and NMR, as well as by comparison with a model compound. The polymers exhibited good solubility in common organic solvents and thermal stability. All the PFAs had high refractive indices in the visible light region(400 nm to 800 nm). Moreover, the PFAs were substantially degraded by UV irradiation due to the presence of furan rings. The film thickness reduction rate could be over 90%.

关键词： Photodegradation Multicomponent reaction Catalyst-free polymerization

Learning a Mixture of Conditional Gating Blocks for Visual Question Answering

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Journal of Computer Science & Technology 2024年第4期39卷 912-928页

作者： qiang Sun Yan-wei fu Xiang-Yang Xue School of Statistics and Information Shanghai University of International Business and EconomicsShanghai 201620China Academy for Engineering and Technology Fudan UniversityShanghai 200433China School of Data Science Fudan UniversityShanghai 200433China School of Computer Science Fudan UniversityShanghai 200433China

As a Turing test in multimedia,visual question answering(VQA)aims to answer the textual question with a given ***,the“dynamic”property of neural networks has been explored as one of the most promising ways of improving the adaptability,interpretability,and capacity of the neural network ***,despite the prevalence of dynamic convolutional neural networks,it is relatively less touched and very nontrivial to exploit dynamics in the transformers of the VQA tasks through all the stages in an end-to-end ***,due to the large computation cost of transformers,researchers are inclined to only apply transformers on the extracted high-level visual features for downstream vision and language *** this end,we introduce a question-guided dynamic layer to the transformer as it can effectively increase the model capacity and require fewer transformer layers for the VQA *** particular,we name the dynamics in the Transformer as Conditional Multi-Head Self-Attention block(cMHSA).furthermore,our questionguided cMHSA is compatible with conditional ResNeXt block(cResNeXt).Thus a novel model mixture of conditional gating blocks(McG)is proposed for VQA,which keeps the best of the Transformer,convolutional neural network(CNN),and dynamic *** pure conditional gating CNN model and the conditional gating Transformer model can be viewed as special examples of *** quantitatively and qualitatively evaluate McG on the CLEVR and VQA-Abstract *** experiments show that McG has achieved the state-of-the-art performance on these benchmark datasets.

关键词： visual question answering Transformer dynamic network

PVP/PAN-derived porous carbon fiber for zinc-ion hybrid supercapacitors

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Rare Metals 2024年第7期43卷 3066-3073页

作者： Shu-Hua Yang Wen-Qing fu Yan-wei Cui Bing-qiang Cao Materials Center for Energy and Photoelectrochemical Conversion School of Material Science and EngineeringUniversity of JinanJinan 250022China

Porous carbon fibers are promising cathodes for zinc-ion hybrid supercapacitors(ZHSs)owing to their abundant active sites,great conductivity,and stable physical and chemical ***,designing a proper preparation technique to regulate the microstructure of carbon fibers still remains a great ***,a poly vinylpyrrolidone/po-lyacry lonitrile(PVP/PAN)-derived porous carbon fiber is developed via the PVP/PAN blend electrospinning and hydrothermal selective PVP removal *** hydrothermal selective PVP removal strategy can effectively avoid a cross-linking between PVP and PAN during the traditional stabilization at air *** PVP/PAN-derived porous carbon fiber,the sufficient micropores provide abundant space for the Zn^(2+)storage,whereas the proper mesopores contribute to the fast ion *** hierarchical porous structures endow ZHSs with high specific capacity and high-rate *** ZHS assembled with the optimal PVP/PAN-derived porous carbon fiber(PVP-PANC-0.8)displays an outstanding specific capacity of 208 mAh·g^(-1),high rate capability(49.5%)from 0.5 to 5 A·g^(-1),and 72.25%capacity retention after 10,000 cycles at 0.5 A·g^(-1).

关键词： Zinc-ion hybrid supercapacitors Porous carbon fibers Hierarchical porous structures Electrospinning

Development in mechanisms of ischemic mitral regurgitation

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Chinese Medical Journal 2013年第9期126卷 1766-1770页

作者： HUANG wei-lin fu qiang Department of Cardiology Zhujiang Hospital Southern Medical University Guangzhou Guangdong 510280 China

Objective The clinical diagnosis and treatment of ischemia mitral regurgitation （IMR） remained difficult because of its unclear mechanisms. This paper reviews studies on the mechanisms of IMR during the last 20 years, and discusses the relevance of the various mechanisms. Data sources Data used in this review were mainly from CNKI and Pubmed in English. The search terms were ＂ischemia mitral regurgitation mechanism＂, ＂myocardial infarction＂ AND ＂mitral regurgitation＂. Study selection Articles were selected if they involved mechanisms of IMR. Results IMR is one of the common complications of coronary artery disease. But currently, the clinical diagnosis and treatment of IMR remained difficult because of its unclear mechanisms. Conclusions For now, dominating theory of ischemic mitral regurgitation mechanisms are left ventricular remodeling, imbalance of leaflet tethering and the closing force, left ventricular dysfunction, changes in spatial structure of the annulus and the dyssynchrony of the left ventricular electromechanical activity.

关键词： myocardial ischemia mitral regurgitation mitral valve insufficiency

Research progress on micro-force measurement of a hydrate particle system

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Petroleum Science 2024年第4期21卷 2169-2183页

作者： qiang Luo wei Li Zhi-Hui Liu Feng Wang Zhi-Chao Liu fu-Long Ning Faculty of Engineering China University of Geosciences (Wuhan) Suzhou Laboratory

It remains a great challenge to understand the hydrates involved in phenomena in practical oil and gas systems. The adhesion forces between hydrate particles, between hydrate particles and pipe walls, and between hydrate particles and reservoir particles are essential factors that control the behaviors of clathrate hydrates in different applications. In this review, we summarize the typical micro-force measurement apparatus and methods utilized to study hydrate particle systems. In addition, the adhesion test results, the related understandings, and the applied numerical calculation models are systematically discussed.

关键词： Clathrate hydrates Hydrate particle Micro-force measurements Adhesion Interactions

Preparation of Self-limiting Heating Cables with Excellent Processability, Mechanical Properties and PTC Effect via Thermal and Electrical Treatments

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Chinese Journal of Polymer Science 2024年第4期42卷 511-520页

作者： Tian-Hao Yang Tong Wu qiang fu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu610065China

Polymer/conductive filler composites have been widely used for the preparation of self-limiting heating cables with the positive temperature coefficient (PTC) effect. The control of conductive filler distribution and network in polymer matrix is the most critical for performance of PTC materials. In order to compensate for the destruction of the filler network structure caused by strong shearing during processing, an excessive conductive filler content is usually added into the polymer matrix, which in turn sacrifices its processability and mechanical properties. In this work, a facile post-treatment of the as-extruded cable, including thermal and electrical treatment to produce high-density polyethylene (HDPE)/carbon black (CB) cable with excellent PTC effect, is developed. It is found for the as-extruded sample, the strong shearing makes the CB particles disperse uniformly in HDPE matrix, and 25 wt% CB is needed for the formation of conductive paths. For the thermal-treated sample, a gradually aggregated CB filler structure is observed, which leads to the improvement of PTC effect and the notable reduction of CB content to 20 wt%. It is very interesting to see that for the sample with combined thermal and electrical treatment, CB particles are agglomerated and oriented along the electric field direction to create substantial conductive paths, which leads to a further decrease of CB content down to 15 wt%. In this way, self-limiting heating cables with excellent processability, mechanical properties and PTC effect have simultaneously been achieved.

关键词： Self-limiting heating cables Positive temperature coefficient Thermal treatment Electrical treatment

From Liquid to Solid‑State Lithium Metal Batteries:fundamental Issues and Recent Developments

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Nano-Micro Letters 2024年第2期16卷 68-125页

作者： Zhao Zhang wei‑qiang Han School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027People’s Republic of China

The widespread adoption of lithium-ion batteries has been driven by the proliferation of portable electronic devices and electric vehicles,which have increasingly stringent energy density *** metal batteries(LMBs),with their ultralow reduction potential and high theoretical capacity,are widely regarded as the most promising technical pathway for achieving high energy density *** this review,we provide a comprehensive overview of fundamental issues related to high reactivity and migrated interfaces in ***,we propose improved strategies involving interface engineering,3D current collector design,electrolyte optimization,separator modification,application of alloyed anodes,and external field regulation to address these *** utilization of solid-state electrolytes can significantly enhance the safety of LMBs and represents the only viable approach for advancing *** review also encompasses the variation in fundamental issues and design strategies for the transition from liquid to solid *** noteworthy is that the introduction of SSEs will exacerbate differences in electrochemical and mechanical properties at the interface,leading to increased interface inhomogeneity—a critical factor contributing to failure in all-solidstate lithium metal *** on recent research works,this perspective highlights the current status of research on developing high-performance LMBs.

关键词： Lithium metal batteries All-solid-state lithium metal battery Li dendrite Solid electrolyte Interface

New insights into the deposition of natural gas hydrate on pipeline surfaces:A molecular dynamics simulation study

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Petroleum Science 2024年第1期21卷 694-704页

作者： Jun Zhang Hai-qiang fu Mu-Zhi Guo Zhao Wang Li-Wen Li Qi Yin You-Guo Yan wei wei wei-Feng Han Jie Zhong School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina Department of Alternative Energy PetroChina Research Institute of Petroleum Exploration&DevelopmentLangfang 065007HebeiChina

Natural gas hydrate(NGH)can cause pipeline blockages during the transportation of oil and gas under high pressures and low *** hydrate adhesion on pipelines is viewed as an efficient way to prevent NGH *** studies suggested the water film can greatly increase hydrate adhesion in gas-dominant ***,by performing the molecular dynamics simulations,we find in water-dominant system,the water film plays different roles in hydrate deposition on Fe and its corrosion ***,due to the strong affinity of water on Fe surface,the deposited hydrate cannot convert the adsorbed water into hydrate,thus,a water film *** water affinities decrease(Fe>Fe_(2)O_(3)>FeO>Fe_(3)O_(4)),adsorbed water would convert to amorphous hydrate on Fe_(2)O_(3)and form the ordered hydrate on FeO and Fe_(3)O_(4)after hydrate *** absorbed water film converts to amorphous or to hydrate,the adhesion strength of hydrate continuously increases(Fe

关键词： Deposition Natural gas hydrate Pipelines Water affinity Adhesion strength

Molecular Ferroelastic Induced by Mono-/Double-Protonation Strategy

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Chinese Journal of Chemistry 2024年第15期42卷 1706-1712页

作者： Jia-Qi Luo Meng-Meng Lun qiang-qiang Jia Zhi-Jie Wang Hai-Feng Lu Yi Zhang Da-wei fu Institute for Science and Applications of Molecular Ferroelectrics Key Laboratory of the Ministry of Education for Advanced Catalysis MaterialsZhejiang Normal UniversityJinhuaZhejiang 321004China Ordered Matter Science Research Center Jiangsu Key Laboratory for Science and Applications of Molecular FerroelectricsSoutheast UniversityNanjingJiangsu 211189China

Molecular ferroelastics with the natural features of mechanical flexibility and switchable spontaneous strain have attracted widespread attention in the scientific community due to their potential applications in tunable gratings,flexible memorizers,strain sensors,and intelligent ***,most designs of molecular ferroelastics remain in the stage of blind exploration,posing a challenge to achieve a functional ferroelastic more ***,we have successfully obtained a molecular ferroelastic,[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2)(Me_(2)NH(CH_(2))_(2)NH_(3)=N,N-dimethylethylenediammonium),under the guidance of the mono-/double-protonation ***_double-protonated[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2) undergoes a paraelastic-ferroelastic phase transition with the Aizu notation of 2/mFi at 322 ***,the theoretical calculation and experimental measurement simultaneously show that[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2) possesses good mechanical flexibility,because its elastic modulus(E)of 8.26 GPa and hardness(H)of 0.45 GPa are smaller than the average values of organic crystals(E of 12.05 GPa and H of 0.5 GPa),which makes it promising to apply in wearable pressure sensors,implantable medical sensors,high-precision tuners,*** work further enriches the molecular ferroelastic family and demonstrates that mono-/double-protonation is one of the effective molecular modification strategies for designing ferroelastics.

关键词： Molecular crystal Ferroelastic Mono-/double-protonation Mechanical flexibility Phase transition Crystal engineering Computational chemistry Molecular dynamics