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Acta Oceanologica Sinica 2004年第1期23卷 179-185页

作者： LEIKun mengwei ZHENGBinghui FUGuo ChineseResearchAcademyofEnvironmentalSciences Beijng100012ChinaReceived22November2003

Dissolved oxygen (DO) concentrations were surveyed in the Daliao River Estuary in autumn to investigate the temporal and spatial trends of DO distributions. The results indicate that DO is weakly stratified in the Yingkou section of the Daliao River Estuary, and remains constant vertically in the areas near and out of the entrance. Horizontally, both instantaneous and continuous observations show that the Yingkou section of the Daliao River Estuary is affected by hypoxic conditions; while no conditions of low DO have been observed in the areas near and out of the entrance. DO-salinity correlations exhibit different controlling factors of DO distributions in different sections of the Daliao River Estuary. At the upstream part of the Yingkou section of the Daliao River (A1-A4), oxygen demanding materials and the associated biochemical processes are the main factor controlling the DO distribution, but in the lower part of the Yingkou section and the area near and out of the entrance (A5-A15), tidal advections are more influential for DO distributions.

关键词： dissolved oxygen Daliao River estuary distribution

Rational design of hollow rice-grainedα-Fe_(2)O_(3)/carbon nanofibers with optimized impedance matching for electromagnetic wave absorption enhanced

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Nano Research 2023年第4期16卷 5676-5684页

作者： Jingshen Xu Na Lu mengwei Yuan Genban Sun Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China Center for Advanced Materials Research Beijing Normal UniversityZhuhai 519087China

Electromagnetic wave absorption materials are widely used in electronic equipment and military ***,high cost and complex preparation processes become a major obstacle in promoting popularization in the civil *** solve the problems above,researchers have made great efforts to develop Fe-based carbon ***,most of the typical composites require a high filling ratio while achieving excellent ***,in this study,carbon nanofibers(CNFs)combined with the hollow rice-grainedα-Fe_(2)O_(3)nanoparticles were prepared by the in-situ transformation *** rational microstructure design provided a solution for reducing the filling ratio,optimizing impedance matching,and improving electromagnetic wave absorption *** strong reflection loss value(−38.1 dB)and broad effective absorption bandwidth(4.6 GHz)for Fe_(2)O_(3)/CNFs composites were achieved with a low filling ratio(20 wt.%),and the analysis of electromagnetic parameters validated that the microstructure of Fe_(2)O_(3)/CNFs plays a crucial role in the performance *** the optimized impedance matching and simple preparation method,Fe_(2)O_(3)/CNFs have broad application prospects in electromagnetic wave absorption.

关键词： electromagnetic wave absorption Fe-based carbon nanofibers impedance matching

Gyroid Triply Periodic Minimal Surface Lattice Structure Enables Improved Superelasticity of CuAlMn Shape Memory Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 1047-1065页

作者： mengwei Wu Chunmei Ma Ruiping Liu Huadong Fu Department of Materials Science and Engineering China University of Mining and Technology(Beijing)Beijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

Improving the shape memory effect and superelasticity of Cu-based shape memory alloys(SMAs)has always been a research hotspot in many *** work systematically investigates the effects of Gyroid triply periodic minimal surface(TPMS)lattice structures with different unit sizes and volume fractions on the manufacturing viability,compressive mechanical response,superelasticity and heating recovery properties of CuAlMn *** results show that the increased specific surface area of the lattice structure leads to increased powder adhesion,making the manufacturability proportional to the unit size and volume *** compressive response of the CuAlMn SMAs Gyroid TPMS lattice structure is negatively correlated with the unit size and positively correlated with the volume *** superelastic recovery of all CuAlMn SMAs with Gyroid TPMS lattice structures is within 5%when the cyclic cumulative strain is set to be 10%.The lattice structure shows the maximum superelasticity when the unit size is 3.00 mm and the volume fraction is 12%,and after heating recovery,the total recovery strain increases as the volume fraction *** study introduces a new strategy to enhance the superelastic properties and expand the applications of CuAlMn SMAs in soft robotics,medical equipment,aerospace and other fields.

关键词： Shape memory alloys Superelasticity Gyroid triply periodic minimal surface(TPMS)lattice structure Selective laser melting(SLM)

Crosstalk between gut microbiota and sepsis

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Burns & Trauma 2021年第1期9卷 145-156页

作者： mengwei Niu Peng Chen Department of Pathophysiology Guangdong Provincial Key Laboratory of ProteomicsSchool of Basic Medical SciencesSouthern Medical UniversityGuangzhou 510515China

Sepsis is an overwhelming inflammatory response to microbial *** management remains a clinical *** role of the gut microbiome in sepsis has gained some *** evidence has demonstrated that gut microbiota regulate host physiological homeostasis mediators,including the immune system,gut barrier function and disease susceptibility ***,maintenance or restoration of microbiota and metabolite composition might be a therapeutic or prophylactic target against critical *** microbiota transplantation and supplementation of probiotics are microbiota-based treatment methods that are somewhat limited in terms of evidence-based *** review focuses on the importance of the crosstalk between the gastrointestinal ecosystem and sepsis to highlight novel microbiota-targeted therapies to improve the outcomes of sepsis treatment.

关键词： Sepsis Microbiota Immune Gut barrier Liver Fecal microbiota transplantation Probiotics

Recent progress of advanced manganese oxide-based materials for acidic oxygen evolution reaction: Fundamentals, performance optimization,and prospects

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Journal of Energy Chemistry 2023年第3期78卷 537-553,I0015页

作者： mengwei Guo Rongrong Deng Chaowu Wang Qibo Zhang Key Laboratory of Ionic Liquids Metallurgy Faculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming 650093YunnanChina State Key Laboratory of Complex Nonferrous Metal Resources Cleaning Utilization in Yunnan Province Kunming 650093YunnanChina

The oxygen evolution reaction(OER) is the basis of various sustainable energy conversion and storage techniques,especially hydrogen production by water *** realize the practical application of hydrogen energy and mass-scale hydrogen production via water electrolysis,several obstacles,such as the multi-electron transfer OER process with sluggish kinetics and overall high reaction barrier,should be *** oxide-based(MnOx) materials,especially MnO_(2),have emerged as promising non-noble electrocatalysts for water electro-oxidation under acidic conditions due to their wellbalanced properties between catalytic activity and *** review introduces the fundamental understanding of the catalytic OER process on MnOx-based materials,including the conventional adsorbate evolution mechanism(AEM) and emerging lattice oxygen oxidation mechanism(LOM).The rational screening and prediction of MnOx-based catalysts that can stably catalyze OER in acid are summarized based on Pourbaix diagram analysis and thermodynamic density functional theory(DFT) ***,the up-to-date progress of upgrading the OER catalytic performance of MnOx-based catalysts by composite construction is ***,feasible strategies to improve the electrocatalytic activity and lifetime of MnOx-based catalysts are systemically discussed in terms of crystal structure control,reasonable setting of working potential and electrolyte environment,optimal selection of acid-stable conductive supports,and self-healing ***,future scientific challenges and research directions are outlined to guide the construction of advanced MnOx-based electrocatalysts for OER in acid.

关键词： Manganese oxide-based materials Manganese dioxides Electrocatalysts Oxygen evolution reaction Acidic solution

Flower-like CuS/γ-Fe_(2)O_(3) van der Waals heterostructures with highefficient electromagnetic wave absorption

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Nano Research 2024年第4期17卷 3324-3333页

作者： Na Lu Jingshen Xu mengwei Yuan Genban Sun Beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875China Center for Advanced Materials Research Beijing Normal UniversityZhuhai 519087China

The escalating electromagnetic(EM)pollution issues and the demand to elevate military stealth technology make it imperative to develop cost-effective and high-performance electromagnetic wave(EMW)absorbing *** this paper,the flower-like CuS/γ-Fe_(2)O_(3) van der Waals(vdW)heterostructures have been synthesized via a facile two-step solvothermal *** flower-like CuS skeleton increases the attenuation path of EMW while reducing the material *** contents ofγ-Fe_(2)O_(3) nanoparticles anchor between the flower-like CuS nanosheets to constitute a heterogeneous structure,which enables dielectric and magnetic loss synergistically to optimize impedance matching and remarkably improve the EMW absorption *** minimum reflection loss(RLmin)is-49.36 dB with a thickness of only 1.6 mm and the effective absorption bandwidth(EAB)reaches 4.64 GHz(13.36–18 GHz).By adjusting the thickness of the absorber,the EAB can cover 96%of the GHz ***,the superior absorption of-61.53 dB at middle frequency band can be obtained by adjusting the amount of Fe_(2)O_(3) *** this study,the adjustment of EM parameters and the optimization of impedance matching have been achieved by constructing a novel vdW heterogeneous structure,which provides fresh ideas and references for the design of high-performance EMW absorbing materials.

关键词： flower-like CuS γ-Fe_(2)O_(3) van der Waals heterostructures impedance matching electromagnetic wave absorption

Bischler-Napieralski Cyclization:A Versatile Reaction towards Functional Aza-PAHs and Their Conjugated Polymers

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Chinese Journal of Chemistry 2021年第11期39卷 3101-3112,3113-3114,3115页

作者： mengwei Li Yuan Yuan Yulan Chen Institute of Molecular Plus Department of ChemistryTianjin UniversityTianjin300354 China

Nitrogen atom doped polycyclic aromatic hydrocarbons,the so-called aza-PAHs,and their conjugated polymers are applicable as functional chromophores and organic *** developments of PAHs and heterocyclic chemistry have been made possible by considerable improvements in synthetic methodologies,among which one-step reactions leading directly to an aza-conjugated ring are highly ***-Napieralski cyclization,an old yet efficient reaction,can accomplish this *** the last ten years,this reaction has been successfully used to synthesize a great variety of aza-PAHs *** combination with polymer chemistry is able to provide the corresponding *** feature article summarizes the up-to-data advances,mainly achieved by our groups,on the design and synthesis of new and well-tailored aza-PAHs and macromolecular architectures using Bischler-Napieralski cyclization as the key ***,the versatile applications of these functional materials in the fields of chemosensors,optoelectronic devices,and biomolecular probes are also covered in detail.

关键词： Bischler-Napieralski cyclization Aza-PAHs Conjugated polymers Fluorescence Nitrogen heterocycles Synthetic methods

Deep eutectic solvent-induced synthesis of Ni-Fe catalyst with excellent mass activity and stability for water oxidation

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Green Energy & Environment 2023年第3期8卷 852-863页

作者： Ruichang Xue mengwei Guo Zhuoming Wei Qibo Zhang Key Laboratory of Ionic Liquids Metallurgy Faculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming650093China State Key Laboratory of Complex Nonferrous Metal Resources Cleaning Utilization in Yunnan Province Kunming650093China

Ni-Fe bimetallic electrodes are currently recognized as a kind of benchmark transition metal-based oxygen evolution reaction(OER)*** synthesis of Ni-Fe bimetallic electrode materials with excellent catalytic activity and satisfied stability by a simple and low-cost route is still a big ***,well-defined Ni-Fe nanoparticles in-situ developed on a planar Fe substrate(Ni-Fe NPs/Fe)is fabricated via a facile one-step galvanic replacement reaction(GRR)carried out in an Ethaline-based deep eutectic solvent(DES).The prepared Ni-Fe NPs/Fe exhibits outstanding OER performance,which needs an overpotential of only 319 mV to drive a current density of 10 mA cm^(-2),with a small Tafel slope of 41.2 mV dec^(-1) in 1.0 mol L^(-1) KOH,high mass activity(up to 319.78 A g^(-1) at an overpotential of 300 mV)and robust durability for 200 ***,the Ni-Fe bimetallic oxygen-evolution electrode obtained from the Ethaline-based DES is catalytically more active and durable than that of its counterpart derived from the 4.2 mol L^(-1) NaCl aqueous *** reason for this is mainly related to the different morphology and surface state of the Ni-Fe catalysts obtained from these different solvent environments,particularly for the differences in phy-chemical properties,active species formed and deposition kinetics,offered by the Ethaline-based DES.

关键词： Ni-Fe catalysts Galvanic replacement reaction Deep eutectic solvent Oxygen evolution reaction

All-inorganic ultrathin high-sensitivity transparent temperature sensor based on a Mn-Co-Ni-O nanofilm

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Microsystems & Nanoengineering 2024年第3期10卷 195-205页

作者： Yuanyuan Cui mengwei Sun Changbo Liu Yuan Deng Research Institute for Frontier Science Beihang UniversityBeijing 100191China School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of Intelligent Sensing Materials and Chip Integration Technology of Zhejiang Province Hangzhou Innovation Institute of Beihang UniversityHangzhou 310051China

The demand for optically transparent temperature sensors in intelligent devices is ***,the performance of these sensors,particularly in terms of their sensitivity and resolution,must be further *** study introduces a novel transparent and highly sensitive temperature sensor characterized by its ultrathin,freestanding design based on a Mn-Co-Ni-O *** Mn-Co-Ni-O-based sensor exhibits remarkable sensitivity,with a temperature coefficient of resistance of−4%℃^(−1),and can detect minuscule temperature fluctuations as small as 0.03℃.Additionally,the freestanding sensor can be transferred onto any substrate for versatile application while maintaining robust structural stability and excellent resistance to interference,indicating its suitability for operation in challenging *** practical utility in monitoring the surface temperature of optical devices is demonstrated through vertical integration of the sensor and a micro light-emitting diode on a polyimide ***,an experiment in which the sensor is implanted in rats confirms its favorable biocompatibility,highlighting the promising applications of the sensor in the biomedical domain.

关键词： transparent sensor versatile

Flexible Broadband Light Absorbers with a Superhydrophobic Surface Fabricated by Ultraviolet-assisted Nanoimprint Lithography

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Chemical Research in Chinese Universities 2022年第3期38卷 829-833页

作者： WEI Wanyuan LI mengwei CHEN Yulan Department of Chemistry Tianjin UniversityTianjin100354P.R.China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012P.R.China

We present a simple approach to fabricate a kind of composite films with a superhydrophobic and broadband light absorbing surface by ultraviolet-assisted nanoimprinting over a gradiently deposited composite *** wettability and optical property of the resultant surfaces are tunable by the deposition time before polymerization(T_(s))and mold’s *** robust and elastomeric films exhibiting high sunlight absorptivity up to 98.13%and contact angle of their surfaces up to 150°are prepared under optimized conditions,as using a mold with a small pattern size(hexagonal periodic mold with cylinder diameter of ca.37μm)under T_(s)=10 min for imprinting the crosslinked poly[di(ethylene glycol)ethyl ether acrylate]and poly(isobornyl acrylate)in the presence of polypyrrole(PPy)*** dual functions are found related to the hierarchical architecture of the surface,arising from the synergetic effects of the periodical patterned polymer substrate and spontaneously assembled PPy microstructures on the *** current strategy based on the combination of ultraviolet-assisted nanoimprint lithography and hierarchical assembly of gradiently deposited black nano-fillers offers a new insight into the design of robust superhydrophobic and black surfaces,which is helpful to deepen our understanding of the relationship between liquid/light manipulation and micro/nanostructured surfaces.

关键词： Superhydrophobic surface Black absorber Composite film Ultraviolet-assisted nanoimprint lithography Hierarchical microstructure