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Engineering d-band center of nickel in nickel@nitrogen-doped carbon nanotubes array for electrochemical reduction of CO_(2)to CO and Zn-CO_(2)batteries

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Chinese Chemical Letters 2022年第8期33卷 3721-3725页

作者： Shujin Shen cheng han Bing wang Yingde wang Science and Technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Self-supported transition-metal single-atom catalysts(SACs)facilitate the industrialization of electrochemical CO_(2) reduction,but suffer from high structural heterogeneity with limited catalytic selectivity.Here we present a facile and scalable approach for the synthesis of self-supported nickel@nitrogen-doped carbon nanotubes grown on carbon nanofiber membrane(Ni@NCNTs/CFM),where the Ni single atoms and nanoparticles(NPs)are anchored on the wall and inside of nitrogen-doped carbon nanotubes,respectively.The side effect of Ni NPs was further effectively inhibited by alloying Ni with Cu atoms to alter their d-band center,which is theoretically predicted and experimentally proved.The optimal catalyst Ni_(9)Cu_(1)@NCNTs/CFM exhibits an ultrahigh CO Faradic efficiency over 97%at-0.7 V versus reversible hydrogen electrode.Additionally,this catalyst shows excellent mechanical strength which can be directly used as a self-supporting catalyst for Zn-CO_(2) battery with a peak power density of~0.65 mW/cm^(2)at2.25 mA/cm^(2) and a long-term stability for 150 cycles.This work opens up a general avenue to facilely prepare self-supported SACs with unitary single-atom site for CO_(2) utilization.

关键词： CO_(2)reduction Electrocatalysis Self-supported catalysts Single atom Zn-CO_(2)battery

A Biosurfactant-containing TSD Strategy to Modify Bovine Pericardial Bioprosthetic Valves for Anticalcification

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Chinese Journal of Polymer Science 2023年第1期41卷 51-66页

作者： Cai-Yun Gao Gang wang Lin wang Qun-Song wang Han-Cheng Wang Lin Yu Jian-Xiong Liu Jian-Dong Ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200438China R&D Center Lifetech Scientific(Shenzhen)Co.Ltd.Shenzhen518057China R&D Center Lifevalve Medical Scientific Co.Ltd.Shenzhen518057China

Bioprosthetic heart valves(BHVs)are important for transcatheter valve replacement.Current commercial BHVs on the market are basically porcine or bovine pericardium(BP)crosslinked with glutaraldehyde(GA).Simply applying GA to BHVs can enhance mechanical stability,but cannot alleviate in vivo calcification.In this work,we developed a two-step decellularization(TSD)strategy to modify this biomacromolecular network,in which BP was post-treated,as the second step of decellularization,with a mild biosurfactant n-dodecyl-β-D-maltoside in a mixture of isopropanol and phosphate-buffered saline after the first step of traditional decellularization and GA cross-linking.The TSD-treated BP exhibited not only low cytotoxicity and excellent mechanical properties in vitro,but also low immune responses and significant anticalcification in vivo.After 60 days of subcutaneous implantation in the back of Wistar rats,the calcium content was,as quantified with an inductively coupled plasma optical emission spectrometer,only 1.1µg/mg compared to 138.6µg/mg in the control group without the post-treatment.In addition,collagen fibrils were observed with field emitting scanning electron microscopy(SEM),and the morphology and composition of the calcified sites resulting from in vivo biomineralization were studied with SEM with energy dispersive spectroscopy and also X-ray diffraction.This study proposes a facile yet effective anticalcification strategy for the modification of the bovine pericardial bioprosthetic heart valve,a natural biomacromolecular network.

关键词： Heart valve Anticalcification Collagen In vivo biomineralization Transcatheter aortic valve implantation(TAVI) Extracellular matrix Biomacromolecular network Biosurfactant Bovine pericardium

Monocular Distance Estimated Based on PTZ Camera

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Computers, Materials & Continua 2024年第5期79卷 3417-3433页

作者： Qirui Zhong Xiaogang cheng Yuxin Song han wang Bell Honors School Nanjing University of Posts and Telecommunications Nanjing210003China College of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing210003China College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing210003China

This paper introduces an intelligent computational approach for extracting salient objects fromimages and estimatingtheir distance information with PTZ (Pan-Tilt-Zoom) cameras. PTZ cameras have found wide applications innumerous public places, serving various purposes such as public securitymanagement, natural disastermonitoring,and crisis alarms, particularly with the rapid development of Artificial Intelligence and global infrastructuralprojects. In this paper, we combine Gauss optical principles with the PTZ camera’s capabilities of horizontal andpitch rotation, as well as optical zoom, to estimate the distance of the object.We present a novel monocular objectdistance estimation model based on the Focal Length-Target Pixel Size (FLTPS) relationship, achieving an accuracyrate of over 95% for objects within a 5 km range. The salient object extraction is achieved through a simplifiedconvolution kernel and the utilization of the object’s RGB features, which offer significantly faster computingspeeds compared to Convolutional Neural Networks (CNNs). Additionally, we introduce the dark channel beforethe fog removal algorithm, resulting in a 20 dB increase in image definition, which significantly benefits distanceestimation. Our system offers the advantages of stability and low device load, making it an asset for public securityaffairs and providing a reference point for future developments in surveillance hardware.

关键词： Public security location information PTZ camera image processing

New insight into the role of exosomes in idiopathic membrane nephropathy

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BIOCELL 2024年第1期48卷 21-32页

作者： JIANHONG LIU KAI HE han wang XIAOHONG cheng Department of Nephrology Shaanxi Provincial Hospital of Traditional Chinese MedicineXian710000China School of BasicMedical Sciences and State Key Laboratory of Southwestern Chinese Medicine Resources Chengdu University of Traditional Chinese MedicineChengdu611137China Department of Pathophysiology West China College of Basic Medical Sciences&Forensic MedicineSichuan UniversityChengdu610041China

Exosomes,nanoscale extracellular vesicles(EVs)derived from the invagination of the endosomal membrane,are secreted by a majority of cell types.As carriers of DNA,mRNA,proteins,and microRNAs,exosomes are implicated in regulating biological activities under physiological and pathological conditions.Kidney-derived exosomes,which vary in origin and function,may either contribute to the pathogenesis of disease or represent a potential therapeutic resource.Membranous nephropathy(MN),an autoimmune kidney disease characterized by glomerular damage,is a predominant cause of nephrotic syndrome.Notably,MN,especially idiopathic membranous nephropathy(IMN),often results in end-stage renal disease(ESRD),affecting approximately 30%of patients and posing a considerable economic challenge to healthcare systems.Despite substantial research,therapeutic options remain ineffective at halting IMN progression,underscoring the urgent need for innovative strategies.Emerging evidence has implicated exosomes in IMN’s pathophysiology;Providing a fresh perspective for the discovery of novel biomarkers and therapeutic strategies.This review aims to scrutinize recent developments in exosome-related mechanisms in IMN and evaluate their potential as promising therapeutic targets and diagnostic biomarkers,with the hope of catalyzing further investigations into the utility of exosomes in MN,particularly IMN,ultimately contributing to improved patient outcomes in these challenging disease settings.

关键词： Exosomes Biomarkers Membranous nephropathy Therapeutic targets

BLNet:Bidirectional learning network for point clouds

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Computational Visual Media 2022年第4期8卷 585-596页

作者： Wenkai han Hai Wu chenglu Wen cheng wang Xin Li School of Informatics Xiamen University422 Siming South RoadXiamen 361005China School of Electrical Engineering and Computer Science Louisiana State UniversityBaton RougeLA 70803USA

The key challenge in processing point clouds lies in the inherent lack of ordering and irregularity of the 3D points.By relying on per-point multi-layer perceptions(MLPs),most existing point-based approaches only address the first issue yet ignore the second one.Directly convolving kernels with irregular points will result in loss of shape information.This paper introduces a novel point-based bidirectional learning network(BLNet)to analyze irregular 3D *** optimizes the learning of 3D points through two iterative operations:feature-guided point shifting and feature learning from shifted points,so as to minimise intra-class variances,leading to a more regular distribution.On the other hand,explicitly modeling point positions leads to a new feature encoding with increased structure-awareness.Then,an attention pooling unit selectively combines important features.This bidirectional learning alternately regularizes the point cloud and learns its geometric features,with these two procedures iteratively promoting each other for more effective feature learning.Experiments show that BLNet is able to learn deep point features robustly and efficiently,and outperforms the prior state-of-the-art on multiple challenging tasks.

关键词： point clouds irregularity shape features bidirectional learning

Surface charge transfer doping for two-dimensional semiconductor-based electronic and optoelectronic devices

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Nano Research 2021年第6期14卷 1682-1697页

作者： Yanan wang Yue Zheng cheng han Wei Chen Department of Physics National University of SingaporeSingapore117542Singapore SZU-NUS Collaborative Innovation Center for Optoelectronic Science&Technology International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of EducationInstitute of Microscale OptoelectronicsShenzhen UniversityShenzhen518060China Department of Chemistry National University of SingaporeSingapore117543Singapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou350207China National University of Singapore(Suzhou)Research Institute Suzhou215123China

Doping of semiconductors,i.e.,accurately modulating the charge carrier type and concentration in a controllable manner,is a key technology foundation for modern electronics and optoelectronics.However,the conventional doping technologies widely utilized in silicon industry,such as ion implantation and thermal diffusion,always fail when applied to two-dimensional(2D)materials with atomically-thin nature.Surface charge transfer doping(SCTD)is emerging as an effective and non-destructive doping technique to provide reliable doping capability for 2D materials,in particular 2D semiconductors.Herein,we summarize the recent advances and developments on the SCTD of 2D semiconductors and its application in electronic and optoelectronic devices.The underlying mechanism of STCD processes on 2D semiconductors is briefly introduced.Its impact on tuning the fundamental properties of various 2D systems is highlighted.We particularly emphasize on the SCTD-enabled high-performance 2D functional devices.Finally,the challenges and opportunities for the future development of SCTD are discussed.

关键词： surface charge transfer doping two-dimensional(2D)semiconductors property modulation electronic devices optoelectronic devices

Developing high-quality g-C_(3)N_(4) film electrode for the photoelectrocatalytic degradation of methylene blue in water

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Chinese Chemical Letters 2023年第3期34卷 175-180页

作者： Yanxi Gong Jianbing wang Zikun cheng Zhiyuan han Xu Zhao Buyu Chai Yuanchun han China University of Mining and Technology-Beijing Beijing 100083China Research Center for Eco-Environment Sciences Chinese Academy of SciencesBeijing 100085China

Developing a high-quality photoelectrode for photoelectrochemical applications is still an ongoing challenge. In this study, we prepared the g-C_(3)N_(4) film on the indium tin oxide(ITO) glass through conventional coating, liquid-based growth, in-situ calcination, and vapor deposition methods, respectively. These electrodes were characterized and used as photoanodes to degrade methylene blue(MB) in water. Among these methods, the in-situ calcination method was most appropriate for preparing the continuous and organized g-C_(3)N_(4) film electrodes with uniform g-C_(3)N_(4) coverage and strong adhesion to the ITO substrate.It also had the highest activity in the photocatalytic(PC), electrochemical(EC), and photoelectrocatalytic(PEC) degradation processes of MB. In the PEC reaction, at an applied potential of 1.0 V and a light intensity of 0.96 W/cm^(2), the removal rate of MB was 62.5%, which was much higher than those in the PC and EC reactions. The high degradation rate was due to the synergistic effect of PEC degradation, wherein the PC and EC reactions promote and optimize each other. In the PC reaction, MB was degraded by-CH_(3) elimination, while the EC degradation pathway mainly included the conversion of sulfhydryl into sulfoxide and the opening of the central aromatic ring. Both methyl loss and aromatic ring opening occurred in the PEC reaction. Moreover, some monocyclic compounds were formed, and MB showed more complete degradation in the PEC reaction.

关键词： Graphitic carbon nitride Photoelectrochemical activity Methylene blue Degradation pathway Synergistic effect

Simple sulfone-bridged heterohelicene structure realizes ultraviolet narrowband thermally activated delayed fluorescence,circularly polarized luminescence,and room temperature phosphorescence

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Science China Chemistry 2022年第9期65卷 1715-1719页

作者： Weimin Ning han wang Shaolong Gong cheng Zhong Chuluo Yang Department of Chemistry Hubei Key Lab on Organic and Polymeric Optoelectronic MaterialsWuhan UniversityWuhan 430072China Shenzhen Key Laboratory of New Information Display and Storage Materials College of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China

Due to narrowband emission and high quantum efficiencies,polycyclic aromatic heterocycles with multi-resonance thermally activated delayed fluorescence(MR-TADF)properties have recently gained considerable attention in the organic optoelectronic field.Albeit their great promise in the full visible region covering from blue to red,MR-TADF emitters with ultraviolet emission have been rarely reported.Through locking the two ortho-positions of a triphenylamine core by sulfone groups,a simple polycyclic aromatic heterocycle,BTPT,was facilely constructed,exhibiting 368 nm ultraviolet emission with a narrow full width at half maximum(FWHM)of 33 nm.Its neat film exhibited distinct TADF property with a main emission peak at 388 nm.Noteworthily,the enantiomeric crystals of BTPT not only demonstrated significant circularly polarized luminescence(CPL)with large luminescence dissymmetry factor in the 10^(-3) order but also displayed obvious room temperature phosphorescence(RTP).The relationship between this innovative helical unit and unique photophysical properties,including ultraviolet MR-TADF,CPL,and RTP,was reasonably revealed.

关键词： polycyclic aromatic heterocycles thermally activated delayed fluorescence multi-resonance effect ultraviolet emission circularly polarized luminescence room temperature phosphorescence

Online preparation of high-quality BN coatings with atomic diffusion based on carbon-free water-soluble precursor

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Journal of Advanced Ceramics 2024年第3期13卷 272-281页

作者： Yiang Du Bing wang Yunbo Zhang Quzhi Song Fuwen wang cheng han Xiaoshan Zhang Yingde wang Science and Technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Efficient and environmentally friendly production of high-quality continuous fiber coatings using current preparation methods is highly challenging due to issues such as scale and batch processing restrictions,low deposition rate,high energy consumption,and utilization of multiple environmentally hazardous steps.To address these challenges,we propose a stable and efficient wet chemical deposition coating method for high-throughput online continuous preparation of boron nitride(BN)coatings on ceramic fibers under an ambient environment.Our process involves surface modification,in-situ wet chemical deposition,and heat treatment,and all seamlessly connecting with the ceramic fiber preparation process through continuous stretching.Hydrophilic groups were introduced via surface modification enhancing wettability of the fiber surface with impregnating solution.An in-situ reaction and atom migration improve uniformity and binding of the coating.As a result,outstanding impregnation and adhesion properties are achieved.A comprehensive analysis to evaluate the impact of the BN coatings was conducted,which demonstrates that the BN-coated fibers exhibit a remarkable 36%increase in tensile strength,a 133%increase in fracture toughness,and enhanced temperature resistance of up to 1600℃.It provides a secure and efficient platform for cost-effective production of functional and high-quality coatings through targeted surface modification and rapid stretching impregnation.

关键词： polymer-derived ceramics SiC fibers wet chemical deposition atomic diffusion boron nitride(BN)coatings