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A novel mullite anti-gyroid/SiC gyroid ceramic metastructure based on digital light processing 3D printing with enhanced electromagnetic wave absorption and mechanical properties

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Journal of Advanced Ceramics 2024年第8期13卷 1212-1222页

作者： Chaoyang wang Xiao chen Zhicheng wang Jjalin Bai Jie Tang Yulong She Zhengren Huang Yong yang State Key Laboratory of High Performance Ceramics and Superfine Microstructures Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China

Sic-based composites are widely used as electromagnetic wave absorbers due to their excellent dielectric ***,the constraints associated with structural design and the intricacies of the preparation process hinder their broader *** this study,novel mullite anti-gyroid/SiC gyroid metastructures are designed to integrate the mechanical and electromagnetic wave(EMW)absorption properties of composite *** anti-gyroid/SiC gyroid composites are fabricated utilizing a combination of digital light processing(DLP)three-dimensional(3D)printing and precursor infiltration and pyrolysis(PiP)*** the modulation of structural units,the electromagnetic parameters can be effectively regulated,thus improving the impedance matching characteristics of the *** structural composites show outstanding EMW absorption properties,with a minimum reflection loss of-54 dB at a thickness of 1.9 mm and an effective absorption bandwidth of 3.20 GHz at a thickness of 2.2 ***,the PIP process significantly enhances the mechanical properties of the composites;compared with those of the mullite/SiC ceramics,the flexural strength of the composites is improved by 3.69-5.85 times(13.28±1.15 MPa vs.(49.05±1.07)-(77.78±3.72)MPa),and the compressive strength is improved by 4.59-13.58 times(8.55±0.90 MPa vs.(39.02±1.63)-(116.13±2.58)MPa).This approach offers a novel and effective method for fabricating structural composites with an expanded range of higher electromagnetic wave absorption properties and improved mechanical properties.

关键词： mullite anti-gyroid/SiC gyroid metastructures digital light processing(DLP) precursor infiltration and pyrolysis(PIP) electromagnetic waveabsorption

Effect of aeration on fast gas pressure tests

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Mining Science and Technology 2009年第6期19卷 756-760页

作者： chen Yu-jia JIANG cheng-lin LI Xiao-wei TANG Jun wang chen yang Fei-long wang Fa-kai ZHANG Chao-jie DENG Shu-hua School of Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Given the problem of the long time required for testing gas pressure, we propose a fast-test method in which we used a technique of fast borehole sealing and air replenishing. Based on the characteristics of gas emission from boreholes to be tested, we built a theoretical model for calculating parameters during the process of increasing natural pressure and aeration. Using this model, we investigated the effect of different aeration conditions on velocity of pressure tests. The result shows that: 1) aerating air into boreholes can speed up gas pressure tests and 2) the more similar the pressure of the aerated air to the original gas pressure, the smaller the gas volume absorbed by coal and the shorter the time needed in pressure test. A case study in the Lu’an mining area shows that the time needed for gas pressure test is only 4 h using our method of aeration and 29 h under conditions of increasing natural pressure, saving time by 86.2%. This case study also indicates that, by using the aeration method, only one hour is needed for gas pressure to reach a stable state, which breaks the record of the shortest time needed for gas pressure tests in China.

关键词： aeration gas pressure fast test aeration pressure adsorption quantity

Surveillance-image-based outdoor air quality monitoring

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Environmental Science and Ecotechnology 2024年第2期18卷 60-69页

作者： Xiaochu wang Meizhen wang Xuejun Liu Ying Mao yang chen Songsong Dai School of Geography Nanjing Normal UniversityNanjing210023China Key Laboratory of Virtual Geographic Environment Nanjing Normal UniversityMinistry of EducationNanjing210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing Normal UniversityNanjing210023China

Air pollution threatens human health,necessitating effective and convenient air quality ***,there has been a growing interest in using camera images for air quality ***,a major challenge has been nighttime detection due to the limited visibility of nighttime *** we present a hybrid deep learning model,capitalizing on the temporal continuity of air quality changes for estimating outdoor air quality from surveillance *** model,which integrates a convolutional neural network(CNN)and long short-term memory(LSTM),adeptly captures spatial-temporal image features,enabling air quality estimation at any time of day,including PM_(2.5) and PM10 concentrations,as well as the air quality index(AQI).Compared to independent CNN networks that solely extract spatial features,our model demonstrates superior accuracy on self-constructed datasets with R^(2)?0.94 and RMSE=5.11 mg m^(-3) for PM_(2.5),R^(2)=0.92 and RMSE=7.30 mg m^(-3) for PM10,and R^(2)=0.94 and RMSE?5.38 for ***,our model excels in daytime air quality estimation and enhances nighttime predictions,elevating overall *** across diverse image datasets and comparative analyses underscore the applicability and superiority of our model,reaffirming its applicability and superiority for air quality monitoring.

关键词： Outdoor air quality estimation Hybrid deep learning model Convolutional neural network Long short-term memory Image sequences

Easy-to-perform organic-solvent-free synthesis of carbon dots with strong green photoluminescence

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Chinese Chemical Letters 2024年第3期35卷 373-378页

作者： Jiazhuang Guo Yifeng chen Pan Zhang Ge Li Xiaoning yang Cai-Feng wang Su chen State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

Carbon dots(CDs)have been extensively studied owing to their fascinating optical properties and wide potential ***,we report an easy-to-perform and organic-solvent-free synthesis strategy for green-emissive CDs(G-CDs)possessing high photoluminescence(PL)quantum yield(QY).The G-CDs are synthesized by heating the homogeneous precursors of citric acid and cyanamide in an open vessel,circumventing the use of organic solvents,complex operations,high-pressure reactors,and expensive instruments in the synthesis *** effect of various reaction variables on the formation and the optical properties of G-CDs are systematically *** resultant G-CDs show bright PL emission at 521 nm with PL QY up to 73%.Then a white light-emitting diode(LED)with Commission Internationable de L'Eclairage(CIE)coordinates of(0.33,0.34)and color rendering index(CRI)of 92 is constructed based on G-CDs/thermoplastic polyurethane(TPU)***,a visual microfluidic detection platform is designed by using G-CDs as fluorescent probes for rapid quantitative detection of Fe^(3+),Cu^(2+),and Mn^(2+)metal ions,which can realize synchronized testing of multiple *** study might promote the development and preparation methods of high-performance CDs with various optical applications.

关键词： Carbon dots Efficient synthesis Green fluorescence Quantum yield White LEDs Microfluidic detection platform

MXene supported PtCo bimetallic catalyst for hydrogen evolution in acidic conditions

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Frontiers in Energy 2024年第3期18卷 369-377页

作者： Guangxun chen Jian-hua ZHANG Kai-Ling ZHOU yang yang Haoxiang MA Yuhong JIN Jingbin LIU Hao wang Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Institute of Deep-Sea Science and Engineering Chinese Academy of SciencesSanya 572000China

Using the electrochemical technology to split water molecules to produce hydrogen is the key to obtain green hydrogen for solving the energy crisis. The large-scale application of hydrogen evolution reaction (HER) in water dissociation requires a highly active catalyst. In this paper, the highly dispersed PtCo bimetallic nanoparticles loading on MXene (PtCo/MXene) were prepared by using a step-to-step reduction strategy. The mentioned PtCo/MXene catalyst exhibits a high current density of −100 mA/cm2 in an acidic medium with just a 152 mV overpotential. In addition, the PtCo/MXene catalyst also displays a superior stability. Computational analysis and experimental testing demonstrate that the electronic interaction between Pt and Co can effectively modify the electronic structure of the active site, thereby enhancing the inherent catalytic performance of the material. More importantly, MXene two-dimensional nanosheets can expose more active sites because of their large specific surface area. Furthermore, MXene substrate with excellent electrical conductivity and harmonious interfaces between PtCo and MXene enhance charge transfer efficiency and lower the reaction activation energy.

关键词： MXene PtCo bimetallic hydrogen evolution reaction(HER)

New Insight into the Flexoelectricity in the View of Mechanics of Materials:Prismatic Beams Subjected to Bending

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Acta Mechanica Solida Sinica 2024年第4期37卷 555-569页

作者： Xu yang Lingling chen Shengyou yang Department of Engineering Mechanics School of Civil EngineeringShandong UniversityJinan250061China

Flexoelectricity is a fascinating electromechanical phenomenon that occurs in non-homogeneously deformed dielectric *** piezoelectricity,the flexoelectric effect is highly dependent on both the material scale and the deformation *** several theoretical models have been proposed to explain the mechanism of flexoelectricity,these models can be rather complicated for those who are interested in studying the *** paper aims to simplify the understanding of flexoelectricity by focusing on the bending behavior of a prismatic dielectric beam from a mechanics of material *** avoid using complicated mathematical formulations based on continuum mechanics,including advanced tensor algebra and calculus of *** formulation clearly explains how inhomogeneous deformations and material size affect the electromechanical coupling,changing the effective bending stiffness,deflection,and rotation angles of a bending *** hope this paper can help undergraduate students and researchers,who are unfamiliar with the electromechanical coupling in flexoelectricity,to develop an understanding of this phenomenon and encourage further research in this area.

关键词： bending formulation dielectric

Research progress toward the influence of mosquito salivary proteins on the transmission of mosquito-borne viruses

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Insect Science 2024年第3期31卷 663-673页

作者： Zhao-yang wang Kai-Xiao Nie Ji-chen Niu Gong cheng Tsinghua University-Peking University Joint Center for Life Sciences School of MedicineTsinghua UniversityBejingChina Institute of Infectious Diseases Shenzhen Bay LaboratoryShenzhenGuangdongChina Department of Pathogen Biology School of Basic MedicineShandong First Medical University&Shandong Academy of Medical SciencesJinanChina

Mosquito-borne viruses(MBVs)are a large class of viruses transmitted mainly through mosquito bites,including dengue virus,Zika virus,Japanese encephalitis virus,West Nile virus,and chikungunya virus,which pose a major threat to the health of people around the *** global warming and extended human activities,the incidence of many MBVs has increased *** saliva contains a variety of bioactive protein *** not only enable blood feeding but also play a crucial role in regulating local infection at the bite site and the remote dissemination of MBVs as well as in remodeling the innate and adaptive immune responses of host ***,we review the physiological functions of mosquito salivary proteins(MSPs)in detail,the influence and the underlying mechanism of MSPs on the transmission of MBVs,and the current progress and issues that urgently need to be addressed in the research and development of MSP-based MBV transmission blocking vaccines.

关键词： immune response mosquito-borne virus mosquito salivary protein saliva vaccine transmission

Additive manufactured osseointegrated screws with hierarchical design

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Bio-Design and Manufacturing 2024年第2期7卷 206-235页

作者： Wenbo yang Hao chen Haotian Bai Yifu Sun Aobo Zhang yang Liu Yuchao Song Qing Han Jincheng wang Department of Orthopedics Second Hospital of Jilin UniversityChangchun 130022China College of Biological and Agricultural Engineering Jilin UniversityChangchun 130022China School of Materials Science and Engineering Jilin UniversityChangchun 130022China

Bone screws are devices used to fix implants or bones to ***,conventional screws are mechanically fixed with thread and often face long-term failure due to poor *** improve osseointegration,screws are evolving from solid and smooth to porous and *** manufacturing(AM)offers a high degree of manufacturing freedom,enabling the preparation of predesigned screws that are porous and *** paper provides an overview of the problems currently faced by bone screws:long-term loosening and screw ***,advances in osseointegrated screws are summarized hierarchically(sub-micro,micro,and macro).At the sub-microscale level,we describe surface-modification techniques for enhancing *** the micro level,we summarize the micro-design parameters that affect the mechanical and biological properties of porous osseointegrated screws,including porosity,pore size,and pore *** addition,we highlight three promising pore shapes:triply periodic minimal surface,auxetic structure with negative Poisson ratio,and the Voronoi *** the macro level,we outline the strategies of graded design,gradient design,and topology optimization design to improve the mechanical strength of porous osseointegrated ***,this paper outlines advances in AM technology for enhancing the mechanical properties of porous osseointegrated *** osseointegrated screws with hierarchical design are expected to provide excellent long-term fixation and the required mechanical strength.

关键词： Bone screws Additive manufacturing Architecture design Surface modification

A widely targeted metabolite modificomics strategy for modified metabolites identification in tomato

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Journal of Integrative Plant Biology 2024年第4期66卷 810-823页

作者： Jun yang Ridong chen Chao wang Chun Li Weizhen Ye Zhonghui Zhang Shouchuang wang School of Breeding and Multiplication(Sanya Institute of Breeding and Multiplication) Hainan UniversitySanya 572025China School of Tropical Agriculture and Forestry Hainan UniversityHaikou 572208China

The structural and functional diversity of plant metabolites is largely created via chemical modification of a basic ***,metabolite modifications in plants have still not been thoroughly investigated by metabolomics *** this study,a widely targeted metabolite modificomics(WTMM)strategy was developed based on ultra-high performance liquid chromatography-quadrupole-linear ion trap(UHPLC-Q-Trap)and UHPLC-Q-Exactive-Orbitrap(UHPLC-QE-Orbitrap),which greatly improved the detection sensitivity and the efficiency of identification of modified metabolites.A metabolite modificomics study was carried out using tomato as a model,and over 34,000 signals with MS2 information were obtained from approximately 232 neutral loss *** metabolite profiling was also performed by utilizing high-resolution mass spectrometry data to annotate a total of 2,118 metabolites with 125 modification types;of these,165 modified metabolites were identified in this ***,the WTMM database was used to assess diseased tomato tissues and 29 biomarkers were *** summary,the WTMM strategy is not only capable of large-scale detection and quantitative analysis of plant-modified metabolites in plants,but also can be used for plant biomarker development.

关键词： LC-MS metabolic diversity metabolite modificomics modified groups tomato