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Chinese Journal of Aeronautics 2024年第7期37卷 109-133页

作者： Jianfei WEI Silong zhang Jingying ZUO Xin LI Jiang QIN wen BAO School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Supersonic fuel film cooling is a promising way to simultaneously reduce the severe wall heat and friction load of the internal passage in a scramjet engine when operating at hypersonic *** eddy simulations were performed to investigate the cooling and wall friction characteristics of hydrogen and hydrocarbon films under inert and reactive *** results show that the essential difference of the turbulent state in the mixing layer contributes to the totally different behaviors of the cooling and wall friction reduction performances of the two fuel *** turbulent transport processes between the hydrogen film and the mainstream are much weaker as compared to the case of hydrocarbon film,making inert hydrogen rather superior in cooling and friction reduction ***,the increase of wall temperature for hydrogen film under the inert case is mainly driven by the loss of hydrogen with high heat capacity instead of by direct heat ***,the film cooling performance severely deteriorates when the hydrogen film burns due to presence of severe heat release sources near the *** the other hand,combustion of hydrocarbon film in the boundary layer can remarkably improve its originally barely-satisfactory cooling and friction reduction performance to the level comparable to that of hydrogen film,due to the suppression of turbulent transport processes in the mixing layer and presence of heat absorption sources near the ***,the hydrogen film is more advantageous in friction reduction,while the hydrocarbon film is more suitable for cooling.

关键词： Supersonic film cooling Hydrogen Hydrocarbon Boundary layer combustion Large eddy simulation

Insight into the Role and Evidence of Oxygen Vacancies in Porous Single-Crystalline Oxide to Enhance Catalytic Activity and Durability

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Research 2024年第2期2023卷 675-683页

作者： Lingting Ye Jiaming Ma Jie zhang wen Yin Yuanguang Xia Kui Xie Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujan Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China FuzhouFujian 350108China Advanced Energy Science and Technology Guangdong Laboratory 29 Sanxin North RoadHuizhouGuangdong 116023China Spallation Neutron Source Science Center DongguanGuangdong 523803China

Introducing and stabilizing oxygen vacancies in oxide catalysts is considered to be a promising strategy for improving catalytic activity and ***,we quantitatively create oxygen vacancies in the lattice of porous single-crystallineβ-Ga_(2)O_(3)monoliths by reduction treatments and stabilize them through the long-range ordering of crystal lattice to enhance catalytic activity and *** combination analysis of time-of-flight neutron powder diffraction and extended x-ray absorption fine structure discloses that the preferential generation of oxygen vacancy tends to occur at the site of tetrahedral coordination oxygen ions(O_(Ⅲ)sites),which contributes to the formation of unsaturated Ga-O coordination in the monoclinic *** oxygen vacancies are randomly distributed in lattice even though some of them are present in the form of domain defect in the PSC Ga_(2)O_(3)monoliths after the reduction *** number of oxygen vacancies in the reduced monoliths gives 2.32×10^(13),2.87×10^(13),and 3.45×10^(13)mg^(-1)for the Ga_(2)O_(2.952),Ga_(2)O_(2.895),and Ga_(2)O_(2.880),*** therefore demonstrate the exceptionally high C_(2)H_(4)selectivity of~100%at the C_(2)H_(6)conversion of~37%for nonoxidative dehydrogenation of C_(2)H_(6)to C_(2)H_(4).We further demonstrate the excellent durability even at 620℃for 240 h of continuous operation.

关键词： durability coordination Oxygen

Highly reversible Zn anode enabled by anticatalytic carbon layer with suppressed hydrogen evolution

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Rare Metals 2024年第7期43卷 3044-3054页

作者： wen-Duo zhang Chuang Sun Yu-Xuan Zhu Feng Gao Chao Lai School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou221116China

Aqueous zinc-ion batteries(AZIBs)have emerged as a promising high-efficiency energy storage system due to the high energy density,low-cost and environmental ***,the practical application of AZIBs is severely restricted by the challenges faced by the Zn anode,which include uncontrollable dendrite growth,corrosion and hydrogen evolution ***,a simple and convenient physical vapor deposition(PVD)method is reported for fabricating uniform graphite as a protection layer on the surface of Zn *** high conductivity graphite layer on Zn anode(denoted as Zn@C)not only benefits the uniform distribution of the electric field,but also provides numerous Zn nucleation sites to regulate and navigate Zn-ion stripping/plating ***,the graphite layer with a poor catalytic activity endows the Zn@C anode with a highly suppressed hydrogen ***,a hydrogen and dendrite free anode is achieved with artificial anticatalytic carbon layer on Zn anode,exhibiting a high reversibility and excellent cycling stability over 2600 h at the current density of 5 mA·cm^(-2)with a capacity of 2.5 mAh·cm^(-2)and longtime cycling stability for assembled full *** work strategically designs the properties of the artificial interface layer to effectively address various challenges simultaneously,which presents insights for the future development of high-performance rechargeable AZIBs.

关键词： Zn metal anode Artificial anticatalytic layer Hydrogen suppression Dendrite free

Complete kinetic model for esterification reaction of lauric acid with glycerol to synthesize glycerol monolaurate

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Chinese Journal of Chemical Engineering 2024年第6期70卷 211-221页

作者： Han-Qiao Hu Yue zhang Ming Fan Yong Cai Guang-wen Chu Liang-Liang zhang Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Petrochemical Research Institute China National Petroleum CorporationBeijing 102206China

Glycerol monolaurate(GML)is a widely used industrial chemical with excellent emulsification and antibacterial *** direct esterification of glycerol with lauric acid is the main method to synthesize *** this work,the kinetic process of direct esterification was systematically studied using p-toluenesulfonic acid as catalyst.A complete kinetic model of consecutive esterification reaction has been established,and the kinetic equation of acid catalysis was *** isomerization reactions of GML and glycerol dilaurate were *** was found that the reaction was an equilibrium reaction and the reaction rate was faster than the esterification *** kinetic equations of the consecutive esterification reaction were obtained by experiments as k_(1)=(276+92261Xcat)exp(-37720/RT)and k_(2)=(80+4413Xcat)exp(-32240/RT).The kinetic results are beneficial to the optimization of operating conditions and reactor design in GML production process.

关键词： Glycerol monolaurate p-Toluenesulfonic acid Esterification Kinetics Mass transfer

Rheological Behaviors of Polymers with Nanoparticles Tethered at Each End

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Chinese Journal of Polymer Science 2024年第3期42卷 400-406,I0009页

作者： Song-Qi zhang wen-Qing Wang Jia-Ping Lin Li-Quan Wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from-1/2 to-3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology.

关键词： Polymer rheology Modulus Viscosity Molecular dynamics

A thermo-responsive rewritable plasmonic bio-memory by regulating single core-satellite gold nanocluster dissociation

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Nano Research 2024年第8期17卷 7275-7282页

作者： wen zhang Yi Wang Yamin Wang Xiaomei Lu Weibing Wu Quli Fan Lei zhang State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Nanjing University of Posts&TelecommunicationsNanjing 210023China Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources College of Light Industry and Food EngineeringNanjing Forestry UniversityNanjing 210037China Zhengzhou Institute of Biomedical Engineering and Technology Zhengzhou 450001China Key Laboratory of Flexible Electronics(KLOFE) Institute of Advanced Materials(IAM)&School of Flexible Electronics(Future Technologies)Nanjing Tech University(Nanjing Tech)Nanjing 211816China

A thermo-responsive rewritable plasmonic bio-memory chip has been successfully fabricated on an indium tin oxide(ITO)glass slide by assembling core-satellite gold nanoclusters with different size of gold nanoparticles(AuNPs)using double-strand DNA(dsDNA)*** the prepared 70@DNA20@13 gold nanoclusters(AuNCs)exhibited more stable and greater photothermal conversion *** short time irradiation by 633 nm microbeam laser,every individual AuNCs could be excited and remove the satellite AuNPs on its ***,in the dissociation process of AuNCs with 3−5 satellite,its color would change from yellow to green,which showed more significant reduction in the red channel of the dark-field microscopy(DFM)images and could be defined to state“0”and“1”***,this plasmonic nano bio-memory could transform cyclically its state between 0 and 1 which exhibited excellent rewritable ability.

关键词： plasmonic assembly thermal-responsive single nanoparticle rewritable bio-memory

pH Induced Self-assembly of AIE Fluorescent Probe for Tumor Imaging

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Chinese Journal of Polymer Science 2024年第1期42卷 7-13,I0005页

作者： Jing-Yuan Xiang wen-Long zhang He-Ting Li Ya-Ning He Department of Chemical Engineering Key Laboratory of Advanced Materials(MOE)Tsinghua UniversityBejing 100084China

This work reported an AIE fluorescent probe for tumor imaging based on the p H induced self-assembly strategy. The fluorescent probe was composed of an acid-responsive soluble copolymer PEG-b-PAMA-DMMA with a maleic acid amide group and an anionic soluble aggregation-induced emission fluorogen(AIEgen) TPE-2SO_(3)^(-). The polymer could be transformed into a protonated amine-containing polymer after the hydrolysis of maleic acid amide in acidic tumor microenvironment, which would be further self-assembled with TPE-2SO_(3)^(-)to form aggregated nanoparticles. The transition of TPE-2SO_(3)^(-)from dispersed state to aggregated state led to an obvious increase in fluorescence intensity due to its AIE characteristics.

关键词： p H-responsive Self-assembly Fluorescent probe AIE Tumor imaging

BMSC-derived Exosomes Ameliorate Peritoneal Dialysis-associated Peritoneal Fibrosis via the Mir-27a-3p/TP53 Pathway

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Current Medical Science 2024年第2期44卷 333-345页

作者： Jun-li ZHAO Lin ZHAO Qiu-nan ZHAN Miao LIU Ting zhang wen-wen CHU Department of Nephrology Shanghai University of Medicine&Health Sciences Affiliated Zhoupu HospitalShanghai 201318China Orthopedic Department Guangming Traditional Chinese Medicine Hospital of Pudong New AreaShanghai 201399China

Objective:Peritoneal fibrosis(PF)is the main cause of declining efficiency and ultrafiltration failure of the peritoneum,which restricts the long-term application of peritoneal dialysis(PD).This study aimed to investigate the therapeutic effects and mechanisms of bone marrow mesenchymal stem cells-derived exosomes(BMSC-Exos)on PF in response to ***:Small RNA sequencing analysis of BMSC-Exos was performed by second-generation sequencing.C57BL/6J mice were infused with 4.25%glucose-based peritoneal dialysis fluid(PDF)for 6 consecutive weeks to establish a PF model.A total of 36 mice were randomly divided into 6 groups:control group,1.5%PDF group,2.5%PDF group,4.25%PDF group,BMSC-Exos treatment group,and BMSC-Exos+TP53 treatment *** transcription quantitative polymerase chain reaction(RT-qPCR)was performed to measure the expression level of miR-27a-3p in BMSC-Exos and peritoneum of mice treated with different concentrations of *** and Masson staining were performed to evaluate the extent of *** therapeutic potential of BMSC-Exos for PF was examined through pathological examination,RT-qPCR,Western blotting,and peritoneal function ***-mesenchymal transition(EMT)of HMrSV5 was induced with 4.25%*** were divided into control group,4.25%PDF group,BMSC-Exos treatment group,and BMSC-Exos+TP53 treatment *** Counting Kit-8 assay was used to measure cell viability,and transwell migration assay was used to verify the capacity of BMSC-Exos to inhibit EMT in HMrSV5 ***:Small RNA sequencing analysis showed that miR-27a-3p was highly expressed in BMSC-derived exosomes compared to *** RT-qPCR results showed that the expression of miR-27a-3p was upregulated in BMSC-Exos,but decreased in PD *** found that PF was glucose concentration-dependently enhanced in the peritoneum of the PD *** with the control mice,the PD mice showed high solute transport and decreased ultrafiltration volume as well as an obvious f

关键词： peritoneal fibrosis bone marrow mesenchymal stem cell-derived exosomes miR-27a-3p TP53 epithelialmesenchymal transition

Reducing Operation Emissions and Improving Work Efficiency Using a Pure Electric Wheel Drive Tractor

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Engineering 2024年第6期37卷 230-245页

作者： Chang-Kai wen wen Ren Qing-Zhen Zhu Chun-Jiang Zhao Zhen-Hao Luo Sheng-Li zhang Bin Xie Zhi-Jun Meng Research Center of Intelligent Equipment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China State Key Laboratory of Intelligent Agricultural Power Equipment Beijing 100097China BYD Company Limited Shenzhen 518118China College of Agricultural Engineering Jiangsu UniversityZhenjiang 212013China College of Engineering China Agricultural UniversityBeijing 100083China

In response to the problems of excessive greenhouse-gas and particulate emissions and the low traction efficiency of conventional diesel tractors in the field,a purely electric wheel-side drive tractor was studied,including an electric motor drive system,a battery ballast system,and an electro–hydraulic suspension *** paper develops a dynamics model of an electric tractor-ploughing unit under complex soil conditions,leading to the proposal of an active control method for drive wheel torque and a joint control method for the traction force of the suspension system and the front-and rear-axle loads of a ***,the tractor is prototyped and assembled,and ploughing tests are carried *** ploughing results show that the active torque-distribution control method proposed in this study reduces the tractor slip by 14.83%and increases the traction efficiency by 10.28%compared with the average torquedistribution *** with the conventional traction control mode,the joint control method for traction and ballast proposed in this paper results in a 3.7%increase in traction efficiency,a 15.05%decrease in slip,and a 4.9%reduction in total drive motor energy *** study will help to improve the operation quality and traction efficiency of electric tractors in complex soil conditions.

关键词： Electric tractor Ploughing unit Torque distribution Active ballast Traction performance

Robust Information Hiding Based on Neural Style Transfer with Artificial Intelligence

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Computers, Materials & Continua 2024年第5期79卷 1925-1938页

作者： Xiong zhang Minqing zhang Xu AnWang wen Jiang Chao Jiang Pan Yang College of Cryptography Engineering Engineering University of People’s Armed PoliceXi’an710086China Key Laboratory of People’s Armed Police for Cryptology and Information Security Xi’an710086China Key Laboratory of CTC&Information Engineering(Engineering University of People’s Armed Police) Ministry of EducationXi’an710086China Staff Department of People’s Armed Police Ningxia Corps Yinchuan750000China

This paper proposes an artificial intelligence-based robust information hiding algorithm to address the issue of confidential information being susceptible to noise attacks during *** algorithm we designed aims to mitigate the impact of various noise attacks on the integrity of secret information during *** method we propose involves encoding secret images into stylized encrypted images and applies adversarial transfer to both the style and content features of the original and embedded *** process effectively enhances the concealment and imperceptibility of confidential information,thereby improving the security of such information during transmission and reducing security ***,we have designed a specialized attack layer to simulate real-world attacks and common noise scenarios encountered in practical *** adversarial training,the algorithm is strengthened to enhance its resilience against attacks and overall robustness,ensuring better protection against potential *** results demonstrate that our proposed algorithm successfully enhances the concealment and unknowability of secret information while maintaining embedding ***,it ensures the quality and fidelity of the stego *** method we propose not only improves the security and robustness of information hiding technology but also holds practical application value in protecting sensitive data and ensuring the invisibility of confidential information.

关键词： Information hiding neural style transfer robustness