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Open-Shell Oligomers and Polymers: Theory, Characterization Methods, Molecular Design, and Applications

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Chinese Journal of Polymer Science 2024年第4期42卷 417-436页

作者： Xue-Qing Wang Cheng song ting Lei Key Laboratory of Polymer Chemistry and Physics(Ministry of Education) School of Materials Science and EngineeringPeking UniversityBeijing100871China

Open-shell oligomers and polymers have exhibited intriguing electronic and magnetic properties, making them highly desirable for a wide range of applications, including ambipolar organic field-effect transistors (OFETs), photodetectors, organic thermoelectrics, and spintronics. Although open-shell ground states have been observed in certain small molecules and doped organic semiconductors, the exploration of open-shell ground-state conjugated polymers is still limited, and the strategies for designing these polymers remain obscure. This review aims to briefly introduce the theory and characterization methods of open-shell conjugated polymers, along with an overview of recent progress and applications. The objective is to stimulate further advancements and investigations in this promising area by shedding light on the potential of open-shell conjugated polymers and the challenges that lie ahead.

关键词： Conjugated polymers Open-shell molecules High-spin ground state Donor-acceptor(D-A)polymers Optoelectronic and magnetic properties

Low-Brightness Object Recognition Based on Deep Learning

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Computers, Materials & Continua 2024年第5期79卷 1757-1773页

作者： Shu-yin Chiang ting-Yu Lin Department of Information and Telecommunications Engineering Ming Chuan UniversityTaoyuan City333Taiwan

This research focuses on addressing the challenges associated with image detection in low-light environments,particularly by applying artificial intelligence techniques to machine vision and object recognition *** primary goal is to tackle issues related to recognizing objects with low brightness *** this study,the Intel RealSense Lidar Camera L515 is used to simultaneously capture color information and 16-bit depth information *** detection scenarios are categorized into normal brightness and low brightness *** the system determines a normal brightness environment,normal brightness images are recognized using deep learning *** low-brightness situations,three methods are proposed for *** first method is the SegmentationwithDepth image(SD)methodwhich involves segmenting the depth image,creating amask from the segmented depth image,mapping the obtained mask onto the true color(RGB)image to obtain a backgroundreduced RGB image,and recognizing the segmented *** second method is theHDVmethod(hue,depth,value)which combines RGB images converted to HSV images(hue,saturation,value)with depth images D to form HDV images for *** third method is the HSD(hue,saturation,depth)method which similarly combines RGB images converted to HSV images with depth images D to form HSD images for *** experimental results,in normal brightness environments,the average recognition rate obtained using image recognition methods is 91%.For low-brightness environments,using the SD method with original images for training and segmented images for recognition achieves an average recognition rate of over 82%.TheHDVmethod achieves an average recognition rate of over 70%,while the HSD method achieves an average recognition rate of over 84%.The HSD method allows for a quick and convenient low-light object recognition *** research outcome can be applied to nighttime surveillance systems or nighttime road safety systems

关键词： Low-brightness depth image image segmentation image recognition HDV HSD

Joint Optimization of Resource Allocation and Trajectory Based on User Trajectory for UAV-Assisted Backscatter Communication System

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China Communications 2024年第2期21卷 197-209页

作者： Peizhong Xie Junjie Jiang ting Li yin Lu School of Communication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China

The Backscatter communication has gained widespread attention from academia and industry in recent years. In this paper, A method of resource allocation and trajectory optimization is proposed for UAV-assisted backscatter communication based on user trajectory. This paper will establish an optimization problem of jointly optimizing the UAV trajectories, UAV transmission power and BD scheduling based on the large-scale channel state signals estimated in advance of the known user trajectories, taking into account the constraints of BD data and working energy consumption, to maximize the energy efficiency of the system. The problem is a non-convex optimization problem in fractional form, and there is nonlinear coupling between optimization *** iterative algorithm is proposed based on Dinkelbach algorithm, block coordinate descent method and continuous convex optimization technology. First, the objective function is converted into a non-fractional programming problem based on Dinkelbach method,and then the block coordinate descent method is used to decompose the original complex problem into three independent sub-problems. Finally, the successive convex approximation method is used to solve the trajectory optimization sub-problem. The simulation results show that the proposed scheme and algorithm have obvious energy efficiency gains compared with the comparison scheme.

关键词： energy efficiency joint optimization UAV-assisted backscatter communication user trajectory

Interface engineering of 2D NiFe LDH/NiFeS heterostructure for highly efficient 5-hydroxymethylfurfural electrooxidation

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Chinese Chemical Letters 2024年第9期35卷 514-520页

作者： Lili Wang Ya Yan Rulin Li Xujie Han Jiahui Li ting Ran Jialu Li Baichuan Xiong Xiaorong song Zhaohui yin Hong Wang Qingjun Zhu Bowen Cheng Zhen yin State Key Laboratory of Separation Membranes and Membrane Processes School of ChemistryTiangong UniversityTianjin 300387China School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China College of Chemical Engineering and Materials Science Tianjin University of Science and TechnologyTianjin 300457China State Key Laboratory of Biobased Fiber Manufacturing Technology Tianjin University of Science and TechnologyTianjin 300457China School of Materials Science and Engineering Tiangong UniversityTianjin 300387China Deutsches Elektronen-Synchrotron DESY Platanenallee 6Zeuthen 15738Germany Department of Chemistry and The Center for the Science of Materials Berlin Humboldt-Universitäzu BerlinBerlin 12489Germany

The electrochemical oxidation of 5-hydroxymethylfurfural(HMF)to valuable chemicals is an efficient way to upgrade biomass molecules and replace traditional catalytic *** is crucial to develop efficient and low-cost earth-abundant electrocatalysts to enhance catalytic performance of HMF ***,a new type of two-dimensional(2D)hybrid arrays consisting of Ni Fe layered double hydroxides(LDH)nanosheets and bimetallic sulfide(Ni Fe S)is constructed via interface engineering for efficient electrocatalytic oxidation of HMF to 2,5-furandicarboxylic acid(FDCA).The preparation process of 2D Ni Fe LDH/NiFeS with ultrathin heterostructure involves in anchoring a Co-based metal-organic framework(Co MOF)as template onto the carbon cloth(CC)via in-situ growth,formation of NiFe LDH on the surface of Co MOF and subsequent partial *** electrocatalyst of Ni Fe LDH/Ni Fe S exhibits outstanding performance towards HMF oxidation,about 98.5%yield for FDCA and 97.2%Faraday efficiency(FE)in the alkaline electrolyte with 10 mmol/L HMF,as well as excellent stability retaining 90.1%FE for FDCA after six cycles ***,even at an HMF concentration of 100 mmol/L,the yield and FE for FDCA remain high at 83.6%and 93.6%,*** findings highlight that 2D heterostructure containing abundant interfaces between Ni Fe LDH nanosheets and Ni Fe S can enhance the intrinsic activity of LDH and thus promote the oxidation reaction ***,the synergistic effect of the bimetallic Ni Fe compounds also improved the selectivity of HMF conversion to *** present work demonstrates that constructing 2D ultrathin heterostructure of Ni Fe LDH/Ni Fe S is a facile strategy via interface engineering to enhance the intrinsic activity of LDH electrocatalysts,which would open new avenues toward low-cost and advanced 2D nanocatalysts for sustainable energy conversion and electrochemical valorization of biomass derivatives.

关键词： Electrocatalytic oxidation Interface engineering 2D ultrathin heterostructure Layered double hydroxides 5-Hydroxymethylfurfural

Platelet-based bioactive systems guided precision targeting and immune regulation for cancer therapy

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Nano Research 2024年第9期17卷 8269-8284页

作者： Xinyi Cai Long Qiu Zhenying Diao Lintao Cai ting yin Hong Pan Guangdong Key Laboratory of Nanomedicine CAS-HK Joint Lab of BiomaterialsCAS Key Laboratory of Biomedical Imaging Science and SystemInstitute of Biomedicine and BiotechnologyShenzhen Institute of Advanced Technology(SIAT)Chinese Academy of SciencesShenzhen 518055China School of pharmacy Guangdong Medical UniversityDongguan 523808China Sino-Euro Center of Biomedicine and Health Shenzhen 518024China

The antitumor effects of conventional drug carriers are often attenuated and limited in application by biological barriers associated with tumor heterogeneity and resistance brought about by low tumor *** the rapid development of nanotechnology,naturally derived bioactive materials,and live cell carriers,a promising strategy emerges for targeting the tumor microenvironment(TME)for precision cancer *** unique injury-targeting properties of platelets can significantly extend functional activity,which cannot be achieved with conventional *** this review,three strategies based on platelet-engineered materials are systematically described,namely nanoparticles for platelet membrane camouflage,engineered activated platelets,and targeted-platelets ***-based nanomaterials can effectively coordinate local and distant tumor-host crosstalk with controlled active tumor site recognition and killing effects due to the presence of specific membrane proteins on the surface and the self-secretion of a large number of *** advances in platelets for effectively overcoming biological barriers and reducing immune resistance in cancer immunotherapy applications will be discussed in future clinical *** review provides an overview of recent research advances in platelet-based bioactive material-directed immunotherapy and chemotherapy to inform future antitumor combination therapies.

关键词： platelets bionic targeting immune modulation precision therapy deep penetration

USP19 Stabilizes TAK1 to Regulate High Glucose/Free Fatty Acid-induced Dysfunction in HK-2 Cells

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Current Medical Science 2024年第4期44卷 707-717页

作者： Xiao-hui YAN yin-na ZHU Yan-ting ZHU Kidney Disease and Dialysis Center Shaanxi Provincial People's HospitalXi'an 710068China Department of Nephrology The Third Affiliated Hospital of Xi'an Medical UniversityXi'an 710000China Nephrology and Hemodialysis Center Shaanxi Provincial People's HospitalXi'an 710068China

Objective Obesity-induced kidney injury contributes to the development of diabetic nephropathy(DN).Here,we identified the functions of ubiquitin-specific peptidase 19(USP19)in HK-2 cells exposed to a combination of high glucose(HG)and free fatty acid(FFA)and determined its association with TGF-beta-activated kinase 1(TAK1).Methods HK-2 cells were exposed to a combination of HG and ***19 mRNA expression was detected by quantitative RT-PCR(qRT-PCR),and protein analysis was performed by immunoblotting(IB).Cell growth was assessed by Cell Counting Kit-8(CCK-8)viability and 5-ethynyl-2′-deoxyuridine(EdU)proliferation *** cycle distribution and apoptosis were detected by flow *** USP19/TAK1 interaction and ubiquitinated TAK1 levels were assayed by coimmunoprecipitation(Co-IP)assays and *** In HG+FFA-challenged HK-2 cells,USP19 was highly ***19 knockdown attenuated HG+FFA-triggered growth inhibition and apoptosis promotion in HK-2 ***,USP19 knockdown alleviated HG+FFA-mediated PTEN-induced putative kinase 1(PINK1)/Parkin pathway inactivation and increased mitochondrial reactive oxygen species(ROS)generation in HK-2 ***,USP19 stabilized the TAK1 protein through ***,increased TAK1 expression reversed the USP19 knockdown-mediated phenotypic changes and PINK1/Parkin pathway activation in HG+FFA-challenged HK-2 *** The findings revealed that USP19 plays a crucial role in promoting HK-2 cell dysfunction induced by combined stimulation with HG and FFAs by stabilizing TAK1,providing a potential therapeutic strategy for combating DN.

关键词： HK-2 cells high glucose free fatty acid dysfunction USP19 deubiquitination

Advanced development of grain boundaries in TMDs from fundamentals to hydrogen evolution application

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Chinese Chemical Letters 2024年第5期35卷 117-129页

作者： Ziyang yin Lingbin Xie Weinan yin ting Zhi Kang Chen Junan Pan yingbo Zhang Jingwen Li Longlu Wang College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts&Telecommunications(NJUPT)Nanjing 210023China Institute of Advanced Materials(IAM)&Institute of Flexible Electronics(Future Technology) Nanjing University of Posts&Telecommunications(NJUPT)Nanjing 210023China

Grain boundary(GB),as a kind of lattice defect,widely exists in two-dimensional transition metal dichalcogenides(2D TMDs),which has complex and diverse influences on the physical/chemical properties of 2D *** are universally considered to be a double-edged sword,although some electrical and mechanical properties of 2D TMDs would be adversely affected leading to the reduced overall quality,certain structure-oriented applications could be realized based on its unique *** this review,we first detailed the atomic structure characteristics of GBs and the corresponding techniques,then we systematically summarized the methods of introducing GBs into 2D ***,we expounded unique electrical,mechanical,and chemical properties of the GBs in 2D TMDs and clarified its internal relationship with the atomic ***,the application of GB structure in hydrogen evolution reaction(HER)is also *** the end,we make a conclusion and put forward outlooks,hoping to further promote the basic research of GB and boost the wide application of 2D TMDs.

关键词： Grain boundary Transition metal dichalcogenides Two-dimensional materials Hydrogen evolution reaction Dislocation Molybdenum disulfide

Electrochemical Dearomative Spirocyclization of N-Acyl Sulfonamides in a Continuous-Flow Cell

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Chinese Journal of Chemistry 2024年第9期42卷 980-984页

作者： ting Liu Zhaojiang Shi Yaofeng Yuan Yuqi Lin Ke-yin Ye Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou University FuzhouFujian350108China

The development of efficient and sustainable methods to obtain spirocyclic compounds is of significance as these structures are widely found in pharmaceuticals and ***,we disclose an electrochemical dearomative spirocyclization of N-acyl sulfonamides in a continuous-flow *** reaction is simple and efficient without external catalysts or supporting electrolytes and could be applied in a decagram-scale synthesis.

关键词： Electrochemistry Continuous-flow Dearomatization Spirocyclization Sulfonamides Cyclization Methodology and reactions

Effect of Ti Particles on the Microstructure and Mechanical Properties of AZ91 Magnesium Matrix Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 513-524页

作者： Lu Xiao ting-ting Liu Yue Chu Bo song Jie Zhao Xian-Hua Chen Kai-Hong Zheng Fu-Sheng Pan College of Materials Science and Engineering Chongqing UniversityChongqing 400044China lntelligent Manufacturing and Automobile School Chongqing College of Electronic EngineeringChongqing 401331China School of Materials and Energy Southwest UniversityChongqing 400715China Science and Technology Research Institute of CNNC 404 Co.LTD Gansu 735100China Institute of New Materials Guangdong Academy of SciencesGuangzhou 510650China

Spherical micro-Ti particle(TiP)-reinforced AZ91 magnesium alloy composites were fabricated by semi-solid stirring assisted ultrasonic vibration,which were then subjected to hot *** microstructure results showed that the addition of Ti particles refined the grain size and decreased the texture intensity of the as-extruded AZ91 *** Al3Ti phase with a thickness of 100 nm formed at the Ti/Mg interface,which had a non-coherent relationship with the magnesium *** as-extruded 1 vol.%TiP/AZ91 composite exhibited the best comprehensive mechanical properties,with yield strength,ultimate tensile strength,and elongation at break of 366 MPa,456 MPa,and 14.6%,respectively,which were significantly higher than those of the AZ91 ***,the addition of Ti particles can improve the strength and ductility of the AZ91 alloy,demonstrating the value of magnesium matrix composites for commercial applications.

关键词： Magnesium matrix composites Ti particles Interface Mechanical properties