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Chinese Chemical Letters 2022年第1期33卷 234-238页

作者： Pengyu Wu Chun Cai Chemical Engineering College Nanjing University of Science and TechnologyNanjing 210094China

Catalytic hydrodeoxygenation(HDO)is one of the most effective methods to upgrade the oxygen-containing compounds derived from coal tar to valuable hydrocarbons.Herein,an efficient bimetallic catalyst Pt_(1)Ni_(4)/MgO was prepared and applied in the HDO of dibenzofuran(DBF).High yield(95%)of the desired product bicyclohexane(BCH)was achieved at 240℃and 1.2 MPa of H_(2).Superior catalytic performance could be ascribed to the"relay catalysis"of Pt sites and Ni sites,and the reaction pathway is proposed as well.Scale-up experiment and recyclability test were also performed,which demonstrated the recyclability and promising potential application of Pt_(1)Ni_(4)/MgO.

关键词： Hydrodeoxygenation Dibenzofuran Bicyclohexane Bimetallic catalyst Relay catalysis

Crystalline BC_(2)N quantum dots

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Nano Research 2023年第5期16卷 7837-7843页

作者： pengyu Zhang Chuang Hou Wei Shao Runsheng Liu Zitong wu Guoan Tai The State Key Laboratory of Mechanics and Control of Mechanical Structures and Laboratory of Intelligent Nano Materials and Devices of Ministry of Education College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

Ternary materials composed of boron,carbon,nitrogen have drawn tremendous attention because of their suitable band gap,high carrier mobility,high thermal conductivity.The properties can effectively compensate for the deficiencies of other typical carbon-based and boron-based materials,such as graphene,borophene,hexagonal boron nitride.Although the theoretical progress has advanced the development of ternary materials,it is still a great challenge to synthesize the new nanostructures with good crystallinity and high yield at low dimensional scales.Herein,we report that BC_(2)N quantum dots(QDs)can be successfully prepared by in-situ two-step thermal decomposition of sodium cyanoborohydride in a hydrogen-rich environment.The results show that the as-prepared BC_(2)N QDs have good crystallinity and high yield.The BC_(2)N QDs have an average lateral size of 3.7 nm and an average thickness of 2.83 nm.The experimental results show that the QDs are semiconducting with an optical band gap of 2.15 eV.Furthermore,a fabricated BC_(2)N QDs-based nonvolatile memory shows a low SET operating voltage(0.74 V)and a high ON/OFF ratio(more than 1.74×10^(3))as well as good stability.

关键词： BC_(2)N quantum dots graphene borophene non-volatile memory

Modulating planarity of cyanine dye to construct highly stable Haggregates for enhanced photothermal therapy

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Nano Research 2023年第1期16卷 970-979页

作者： Kai Wei Yanxin wu pengyu Li Xian Zheng Chendong Ji Meizhen Yin State Key Laboratory of Chemical Resource Engineering Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China

Self-assembly of dyes has become a flexible strategy to modulate their photophysical properties.H-aggregates show great potential to increase heat generation,while the precise designing of H-aggregates as efficient photothermal agents is still challenging.Herein,a quinoline cyanine(QCy)is developed for constructing stable H-aggregated nanoparticles(NPs)to significantly enhance photostability and photothermal conversion efficiency(PCE).With symmetrical rigid planar quinoline structures,QCy has a small and symmetrical dihedral angle(11.9°),which ensures excellent molecular planarity.In aqueous solution,the planar QCy can form closeπ–πmolecular stacking,and fast self-assemble into stable H-aggregates even at low concentrations(1×10−7 M).QCy H-aggregates are sphere-like NPs(QCy NPs)with an average diameter of 120 nm and exhibit high stability.H-aggregation of QCy significantly enhances PCE from 20.1%(non-H-aggregated QCy)to 63.8%(QCy NPs).In addition,the positive charge of quaternarized quinoline provides mitochondrial anchoring ability,which further enhances the photothermal effect.With high PCE and tumor accumulation,QCy NPs in low-doses have been successfully used in photoacoustic imaging-guided tumor photothermal therapy.

关键词： H-aggregation-enhanced photothermal effect molecular planarity quinoline cyanine mitochondrial anchoring low-dose

Fluorinated soft carbon as an ultra-high energy density potassium-ion battery cathode enabled by a ternary phase K_(x)FC

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Journal of Energy Chemistry 2023年第2期77卷 38-44,I0002页

作者： pengyu Chen Bojun Wang Zhenrui wu Xiaobin Niu Chuying Ouyang Hong Li Liping Wang School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina School of Engineering The University of British ColumbiaKelowna V1V 1V7Canada C Innovation Laboratory Contemporary Amperex Technology Ltd.(21C LAB)Ningde 352100FujianChina Key Laboratory for Renewable Energy Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Fluorinated carbons(CFx)have been widely applied as lithium primary batteries due to their ultra-high energy density.It will be a great promise if CFx can be rechargeable.In this study,we rationally tune the C-F bond strength for the alkaline intercalated CFx via importing an electronegative weaker element K instead of Li.It forms a ternary phase K_(x)FC instead of two phases(LiF+C)in lithium-ion batteries.Meanwhile,we choose a large layer distance and more defects CFx,namely fluorinated soft carbon,to accommodate K.Thus,we enable CFx rechargeable as a potassium-ion battery cathode.In detail fluorinated soft carbon CF_(1.01) presents a reversible specific capacity of 339 mA h g^(-1)(797 Wh kg^(-1))in the 2nd cycle and maintains 330 mA h g^(-1)(726 Wh kg^(-1))in the 15th cycle.This study reveals the importance of tuning chemical bond stability using different alkaline ions to endow batteries with rechargeability.This work provides good references for focusing on developing reversible electrode materials from popular primary cell configurations.

关键词： Fluorinated carbon High energy density battery Potassium-ion battery Conversion reaction K-free cathode

An Effective CU Depth Decision Method for HEVC Using Machine Learning

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Computer Systems Science & Engineering 2021年第11期39卷 275-286页

作者： Xuan Sun pengyu Liu Xiaowei Jia Kebin Jia Shanji Chen Yueying wu Beijing University of Technology Beijing100124China Beijing Laboratory of Advanced Information Networks Beijing100124China Beijing Key Laboratory of Computational Intelligence and Intelligent System Beijing100124China Department of Computer Science University of PittsburghPittsburgh15260USA School of Physics and Electronic Information Engineering Qinghai Nationalities University810007QinghaiChina

This paper presents an effective machine learning-based depth selection algorithm for CTU(Coding Tree Unit)in HEVC(High Efficiency Video Coding).Existing machine learning methods are limited in their ability in handling the initial depth decision of CU(Coding Unit)and selecting the proper set of input features for the depth selection model.In this paper,we first propose a new classification approach for the initial division depth prediction.In particular,we study the correlation of the texture complexity,QPs(quantization parameters)and the depth decision of the CUs to forecast the original partition depth of the current CUs.Secondly,we further aim to determine the input features of the classifier by analysing the correlation between depth decision of the CUs,picture distortion and the bit-rate.Using the found relationships,we also study a decision method for the end partition depth of the current CUs using bit-rate and picture distortion as input.Finally,we formulate the depth division of the CUs as a binary classification problem and use the nearest neighbor classifier to conduct classification.Our proposed method can significantly improve the efficiency of interframe coding by circumventing the traversing cost of the division depth.It shows that the mentioned method can reduce the time spent by 34.56%compared to HM-16.9 while keeping the partition depth of the CUs correct.

关键词： HEVC inter-frame coding CU depth

A smart dual-drug nanosystem based on coassembly of plant and food-derived natural products for synergistic HCC immunotherapy

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Acta Pharmaceutica Sinica B 2021年第1期11卷 246-257页

作者： Bingchen Zhang Jiali Jiang Pengyu Wu Junjie Zou Jingqing Le Juanfang Lin Chao Li Bangyue Luo Yongjie Zhang Rui Huang Jingwei Shao Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and Chemotherapy College of ChemistryFuzhou UniversityFuzhou 350116China Institute of Oceanography Minjiang UniversityFuzhou 350108China

Nanotechnology has emerged as an ideal approach for achieving the efficient chemo agent delivery.However,the potential toxicity and unclear internal metabolism of most nano-carriers was still a major obstacle for the clinical application.Herein,a novel"core-shell"co-assembly carrier-free nanosystem was constructed based on natural sources of ursolic acid(UA)and polyphenol(EGCG)with the EpCAM-aptamer modification for hepatocellular carcinoma(HCC)synergistic treatment.As the nature products derived from food-plant,UA and EGCG had good anticancer activities and low toxicity.With the simple and"green"method,the nanodrugs had the advantages of good stability,p H-responsive and strong penetration of tumor tissues,which was expected to increase tumor cellular uptake,long circulation and effectively avoid the potential defects of traditional carriers.The nanocomplex exhibited the low cytotoxicity in the normal cells in vitro,good biosafety of organic tissues and efficient tumor accumulation in vivo.Importantly,UA combined with EGCG showed the immunotherapy by activating the innate immunity and acquired immunity resulting in significant synergistic therapeutic effect.The research could provide new ideas for the research and development of self-assembly delivery system in the future,and offer effective intervention strategies for clinical HCC treatment.

关键词： Natural product Ursolic acid EGCG Aptamer Co-assembly Nanodrug HCC Synergistic treatment Immunotherapy

Nickel-iron borate coated nickel-iron boride hybrid for highly stable and active oxygen evolution electrocatalysis

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Chinese Chemical Letters 2020年第9期31卷 2469-2472页

作者： pengyu Han Tan Tan Fei wu Ping Cai Gongzhen Cheng Wei Luo College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China Department of Orthopaedic Surgery Renmin Hospital of Wuhan UniversityWuhan 430060China Suzhou Institute of wuhan University Suzhou 215123China

The development of efficient and cost-effective electrocatalysts toward anodic oxygen evolution reaction(OER) is crucial for the commercial application of electrochemical water splitting.As the most promising electrocatalysts,the OER performances of nickel-iron-based materials can be further improved by introducing metalloid elements to modify their electron structures.Herein,we developed an efficient hybrid electrocatalyst with nickel-iron boride(NiFeB) as core and amorphous nickel-iron borate(NiFeBi)as shell(NiFeB@NiFeBi) via a simple aqueous reduction.The obtained NiFeB@NiFeBi exhibits a small overpotential of 237 mV at 10 mA/cm^2 and Tafel slope of 57.65 mV/dec in 1.0 mol/L KOH,outperforming most of the documented precious-metal-free based electrocatalysts.Benefiting from the in situ formed amorphous NiFeBi layer,it shows excellent stability toward the oxygen evolution reaction(OER).These findings might provide a new way to design advanced precious-metal-free electrocatalysts for OER and the application of electrochemical water splitting.

关键词： Oxygen evolution reaction Metal boride Metal borate Core-shell

Organic dye assemblies with aggregation-induced photophysical changes and their bio-applications

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Aggregate

Aggregate 2021年第4期2卷 57-71页

作者： Chendong Ji Liming Lai pengyu Li Zhen wu Wenyu Cheng Meizhen Yin State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijingChina

Phototheranostics provide a safe,effective,and noninvasive way for the diagnosis and treatment of contemporary diseases,and organic dyes play a vital role.For example,chemical modification endowed dyes with powerful reactive oxygen species or heat generation ability,favoring for photodynamic therapy and photoacoustic(PA)imaging guided photothermal therapy(PTT)of serious diseases.Therefore,photophysical properties manipulation of dyes has become the focus in current dye chemistry research.The development of aggregate science has made great effort to solve this problem.In recent years,a large number of studies have focused on molecular aggregation behavior and its effect on photophysical performance.The most famous example is the discovery of aggregation-induced emission(AIE)phenomenon.Based on AIE theory,more theories for revealing the relationship between molecular aggregation behavior and photophysical properties were proposed and elucidated.The photophysical property changes caused by dye aggregation have become a unique discipline,guiding the development of molecular science and material science.With the help of molecular self-assembly,controllable aggregation of dyes can be realized,and stable nano-theranostic reagents can be obtained.Furthermore,constructing dye assemblies with various photophysical properties will greatly reduce the cost of theranostic reagents,thus,expanding biomedical applications of organic dyes.Therefore,this review focuses on the photophysical characteristic changes caused by dye aggregation and their biological applications including,fluorescence/phosphorescence/PA imaging as well as photodynamic and PTT.This review will provide guidance for the design of organic dyes,the development of controllable aggregation methods,and the construction of multifunctional phototheranostic reagents.

关键词： aggregation-induced photophysical changes fluorescence imaging organic dye assemblies phosphorescence photodynamic therapy photothermal therapy

Theoretical and experimental investigation of the resonance responses and chaotic dynamics of a bistable laminated composite shell in the dynamic snap-through mode

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 581-602页

作者： Meiqi wu pengyu LV Hongyuan LI Jiale YAN Huiling DUAN Wei ZHANG State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceBIC-ESATCollege of EngineeringPeking UniversityBeijing 100871China Nanchang Innovation Institute of Peking University Nanchang 330096China Department of Mechanics Guangxi UniversityNanning 530004China

The dynamic model of a bistable laminated composite shell simply supported by four corners is further developed to investigate the resonance responses and chaotic behaviors.The existence of the 1:1 resonance relationship between two order vibration modes of the system is verified.The resonance response of this class of bistable structures in the dynamic snap-through mode is investigated,and the four-dimensional(4D)nonlinear modulation equations are derived based on the 1:1 internal resonance relationship by means of the multiple scales method.The Hopf bifurcation and instability interval of the amplitude frequency and force amplitude curves are analyzed.The discussion focuses on investigating the effects of key parameters,e.g.,excitation amplitude,damping coefficient,and detuning parameters,on the resonance responses.The numerical simulations show that the foundation excitation and the degree of coupling between the vibration modes exert a substantial effect on the chaotic dynamics of the system.Furthermore,the significant motions under particular excitation conditions are visualized by bifurcation diagrams,time histories,phase portraits,three-dimensional(3D)phase portraits,and Poincare maps.Finally,the vibration experiment is carried out to study the amplitude frequency responses and bifurcation characteristics for the bistable laminated composite shell,yielding results that are qualitatively consistent with the theoretical results.

关键词： bistable laminated composite shell dynamic snap-through mode Hopf bifurcation chaotic dynamics vibration experiment

User Behavior Optimization Strategy for Electric Vehicle Based on Improving Battery SOH

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User Behavior Optimization Strategy for Electric Vehicle Bas...