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National Science Review 2020年第3期7卷 609-619页

作者： Wanfeng Xiong Hongfang Li Hanhui You Minna cao Rong cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences College of Chemistry and Materials Science Fujian Normal University

Applying metal organic frameworks(MOFs) in electrochemical systems is a currently emerging field owing to the rich metal nodes and highly specific surface area of MOFs. However, the problems for MOFs that need to be solved urgently are poor electrical conductivity and low ion transport. Here we present a facile in situ growth method for the rational synthesis of MOFs@hollow mesoporous carbon spheres(HMCS)yolk–shell-structured hybrid material for the first time. the size of the encapsulated Zeolitic Imidazolate Framework-67(ZIF-67) is well controlled to 100 nm due to the spatial confinement effect of HMCS, and the electrical conductivity of ZIF-67 is also increased significantly. the ZIF@HMCS-25% hybrid material obtained exhibits a highly efficient oxygen reduction reaction activity with 0.823 v(vs. reversible hydrogen electrode) half-wave potential and an even higher kinetic current density(JK= 13.8 m A cm-2) than commercial Pt/C. ZIF@HMCS-25% also displays excellent oxygen evolution reaction performance and the overpotential of ZIF@HMCS-25% at 10 m A cm-2 is 407 m v. In addition, ZIF@HMCS-25% is further employed as an air electrode for a rechargeable Zn–air battery, exhibiting a high power density(120.2 m W cm-2 at 171.4 m A cm-2) and long-term charge/discharge stability(80 h at 5 m A cm-2). this MOFs@HMCS yolk–shell design provides a versatile method for the application of MOFs as electrocatalysts directly.

关键词： metal organic frameworks yolk–shell structure bifunctional electrocatalyst Zn–air battery

Microstructural image based convolutional neural networks for efficient prediction of full-field stress maps in short fiber polymer composites

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Defence technology（防务技术） 2023年第6期24卷 58-82页

作者： S.Gupta t.Mukhopadhyay v.Kushvaha Department of Civil Engineering Indian Institute of Technology JammuJ&KIndia Department of Aerospace Engineering Indian Institute of Technology KanpurUPIndia

the increased demand for superior materials has highlighted the need of investigating the mechanical properties of composites to achieve enhanced constitutive ***-reinforced polymer composites have emerged as an integral part of materials development with tailored mechanical ***,the complexity and heterogeneity of such composites make it considerably more challenging to have precise quantification of properties and attain an optimal design of structures through experimental and computational *** order to avoid the complex,cumbersome,and labor-intensive experimental and numerical modeling approaches,a machine learning(ML)model is proposed here such that it takes the microstructural image as input with a different range of Young’s modulus of carbon fibers and neat epoxy,and obtains output as visualization of the stress component S11(principal stress in the x-direction).For obtaining the training data of the ML model,a short carbon fiberfilled specimen under quasi-static tension is modeled based on 2D Representative Area Element(RAE)using finite element *** composite is inclusive of short carbon fibers with an aspect ratio of 7.5that are infilled in the epoxy systems at various random orientations and positions generated using the Simple Sequential Inhibition(SSI)*** study reveals that the pix2pix deep learning Convolutional Neural Network(CNN)model is robust enough to predict the stress fields in the composite for a given arrangement of short fibers filled in epoxy over the specified range of Young’s modulus with high *** CNN model achieves a correlation score of about 0.999 and L2 norm of less than 0.005 for a majority of the samples in the design spectrum,indicating excellent prediction *** this paper,we have focused on the stage-wise chronological development of the CNN model with optimized performance for predicting the full-field stress maps of the fiber-reinforced composite ***

关键词： Micromechanics of fiber-reinforced composites Machine learning assisted stress prediction Microstructural image-based machine learning CNN based stress analysis

Nonlinear stability of advanced sandwich cylindrical shells comprising porous functionally graded material and carbon nanotube reinforced composite layers under elevated temperature

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Applied Mathematics and Mechanics(English Edition) 2021年第9期42卷 1327-1348页

作者： H.v.tUNG L.t.N.tRANG Faculty of Civil Engineering Hanoi Architectural UniversityHa Noi 10000Viet Nam Faculty of Civil Engineering University of Transport TechnologyHa Noi 10000Viet Nam

the nonlinear stability of sandwich cylindrical shells comprising porous functionally graded material(FGM) and carbon nanotube reinforced composite(CNtRC)layers subjected to uniform temperature rise is investigated. two sandwich models corresponding to CNtRC and FGM face sheets are proposed. Carbon nanotubes(CNts) in the CNtRC layer are embedded into a matrix according to functionally graded distributions. the effects of porosity in the FGM and the temperature dependence of properties of all constituent materials are considered. the effective properties of the porous FGM and CNtRC are determined by using the modified and extended versions of a linear mixture rule, respectively. the basic equations governing the stability problem of thin sandwich cylindrical shells are established within the framework of the Donnell shell theory including the von K’arm’an-Donnell nonlinearity. these equations are solved by using the multi-term analytical solutions and the Galerkin method for simply supported *** critical buckling temperatures and postbuckling paths are determined through an iteration procedure. the study reveals that the sandwich shell model with a CNtRC core layer and relatively thin porous FGM face sheets can have the best capacity of thermal load carrying. In addition, unlike the cases of mechanical loads, porosities have beneficial effects on the nonlinear stability of sandwich shells under the thermal load. It is suggested that an appropriate combination of advantages of FGM and CNtRC can result in optimal efficiency for advanced sandwich structures.

关键词： carbon nanotube reinforced composite(CNtRC) porous functionally graded material(FGM) thermal instability cylindrical shell advanced sandwich model

Synergetic effects of gold-doped copper nanowires with low Au content for enhanced electrocatalytic CO_(2)reduction to multicarbon products

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Nano Research 2023年第5期16卷 7777-7783页

作者： Zongnan Wei Shuai Yue Shuiying Gao Minna cao Rong cao Department of Chemistry University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Fujian Science&technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

As efficient catalysts of electrochemical CO_(2)reduction reaction(CO_(2)RR)towards multicarbon(C_(2+))products,Cu-based catalysts have faced the challenges of increasing the reactive activity and ***,we decorated the surface of Cu nanowires(Cu NWs)with a small amount of Au nanoparticles(Au NPs)by the homo-nucleation *** the Au to Cu mass ratio is as little as 0.7 to 99.3,the gold-doped copper nanowires(Cu-Au NWs)could effectively improve the selectivity and activity of CO_(2)RR to C_(2+)resultants,with the Faradaic efficiency(FE)from 39.7%(Cu NWs)to 65.3%,the partial current density from 7.0(Cu NWs)to 12.1 mA/cm^(2) under−1.25 v *** hydrogen electrode(RHE).the enhanced electrocatalytic performance could be attributed to the following three synergetic *** addition of Au nanoparticles caused a rougher surface of the catalyst,which allowed for more active sites ***,Au sites generated*CO intermediates spilling over into Cu sites with the calculated efficiency of 87.2%,which are necessary for multicarbon ***,the interphase electron transferred from Cu to Au induced the electron-deficient Cu,which favored the adsorption of*CO to further generate multicarbon *** results uncovered the morphology,tandem,electronic effect between Cu NWs and Au NPs facilitated the activity and selectivity of CO_(2)RR to multicarbons.

关键词： electrochemical CO_(2)reduction multicarbon production bimetallic catalyst Cu nanowires Au nanoparticles

Goal-Oriented Anisotropic hp-Adaptive Discontinuous Galerkin Method for the Euler Equations

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Communications on Applied Mathematics and Computation 2022年第1期4卷 143-179页

作者： vít Dolejší Filip Roskovec Faculty of Mathematics and Physics Charles UniversitySokolovská8318675 PragueCzech Republic

We deal with the numerical solution of the compressible Euler equations with the aid of the discontinuous Galerkin(DG)method with focus on the goal-oriented error estimates and *** analyse the adjoint consistency of the DG scheme where the adjoint problem is not formulated by the differentiation of the DG form and the target functional but using a suitable linearization of the nonlinear ***,we present the goal-oriented anisotropic hp-mesh adaptation method for the Euler *** theoretical results are supported by numerical experiments.

关键词： Euler equations Discontinuous Galerkin method target functional Adjoint consistency Anisotropic hp-mesh adaptation

Screening of potential GCMS derived antimigraine compound from the leaves of Abrus precatorius Linn to target“calcitonin gene related peptide”receptor using in silico analysis

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Food Science and Human Wellness 2019年第1期8卷 34-39页

作者： v.Parthasarathy t.v Ajay Kumar Immunology Laboratory Department of PharmacyAnnamalai UniversityAnnamalai Nagar608002TamilnaduIndia

Calcitonin receptor-like receptor(CRLR)is a human protein,that produces a calcitonin gene-related peptide receptor(CGRP)when associates with human receptor activity-modifying protein-1(HRAMP1).CGRP is believed to be involved in triggering of *** strategies were employed to design antimigraine drug using various CGRP antagonist/ligands but most of them have failed due to their inability to reach the target“CGRP receptor”as they get metabolized before conferring their pharmacological action and exhibit toxic effect to the *** present study,evaluated the binding of 13 phyto-chemical compounds of“Abrus precatorius”identified through GCMS analysis against the protein CGRP using“Discovery Studio software”.the molecular docking study and ADME/t properties prediction were performed with the compounds using C-DOCKER *** results showed that five lead compounds of *** may act as good inhibitors for migraine headache and the compounds can be re-designed and synthesized for better antimigraine activity.

关键词： Calcitonin gene-related peptide Abrus precatorius Linn Discovery studio Migraine C-DOCKER ADME properties

Development of Biocomposites of MCC Extracted From Non-Wood Sources

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Journal of Renewable Materials 2019年第11期7卷 1109-1119页

作者： t.Dipin t.v.Jinitha E.Purushothaman Department of Chemistry University of CalicutMalappuramKerala673635India

the present work mainly focuses on the estimation of various components and the extraction of microcrystalline cellulose(MCC)from non-wood sources like Country Almond/Badam shell through acid *** hydrolyzed MCC was successfully used as reinforcement for development of *** Almond/Badam trees are found all over Kerala,India and they give nuts once in a *** the nut shells are discarded and are becoming one of the sources of agricultural *** this investigation various components were isolated from the Country Almond shells and they were characterised using different spectral and analytical techniques thereby the composition of Country Almond shells was successfully determined for the first *** properties of MCC especially the crystalline nature depends on the source from which is ***-IR spectra give evidence for the chemical structure of *** of MCC was evidenced from scanning electron *** electron microscopy and atomic force microscopy reveal the agglomerated bundles of particles and rough surface of *** extracted MCC was found to contain Cellulose I and Cellulose II polymorphs,and this was confirmed from the X-ray diffraction(XRD)*** MCC extracted from Country Almond shells has reasonably good thermal *** casting method was adopted for the development of green composite of Poly(vinyl alcohol)reinforced with MCC extracted from Country Almond *** mechanical property of developed composites has been enhanced by the addition of *** dispersion of MCC in the PvA matrix and flocculation of MCC significantly influence the mechanical strength.

关键词： Country almond/Badam shell microcrystalline cellulose bio composites

Enthalpy of Mixing of Liquid Al-Cr and Cr-Ni Alloys

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Journal of Materials Science & technology 2002年第2期18卷 167-170页

作者： P.Saltykov v.t.Witusiewicz 等 Max-Planck-InstitutfureMetallforschungandUniveristaetStuttgart InstitutfuerNichtmetallischeAnorganischeMaterialienUnversityStuttgartPulvermetallurgischesLaboratoriumHeisenbergstr57056 Max-Planck-I

the partial and the integral enthalpies of mixing of liquid Al-Cr and Ni-Cr binary alloys have been determined by high temperature isoperibolic calorimetry at 1723±5 K and 1729±5 K, respectively. the results were analytically described by the thermodynamically adapted power series (tAPS). the enthalpies of mixing values for both binary liquid melts are small and negative and in good agreement with the available literature data. Minima of the mixing enthalpies of liquid Al-Cr and Ni-Cr alloys are -7.0 kJ·mol-1 at 46 at. pct Cr and -3.0 kJ·mol-1 at 37 at. pct Cr, respectively.

关键词： Al-Cr Cr-Ni Liquid alloys Enthalpy of mixing Isoperibolic calorimetry

Biogenesis,action and biological functions of an Arabidopsis 5' t RF,5' ts R-Ala

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Science China(Life Sciences) 2022年第5期65卷 1050-1052页

作者： Chunyan Liu Bo cao Xiaofeng cao State Key Laboratory of Plant Genomics and National Center for Plant Gene Research(Beijing) Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Microbial Metabolism School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200030China Center for Excellence in Molecular Plant Sciences Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

transfer RNAs(tRNAs) are one class of most conserved and abundant RNA species with 76–90 nucleotides(nt) in *** constitute approximately 4%–15% of total cellular RNAs and are well known for translating the codons on... 详细信息

关键词： action translating toll

Characterization of mixing in an optimized designed t–t mixer with cylindrical elements

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2337-2351页

作者： t.Manoj Dundi v.R.K.Raju v.P.Chandramohan Mechanical Engineering Department National Institute of TechnologyWarangalTelangana StateIndia

Passive micromixers are preferred over active mixers for many microfluidic applications due to their relative ease in integration into complex systems and operational *** also incur very low cost of ***,the degree of mixing is comparatively low in passive mixers than active mixers due to the absence of disturbance in the flow by external forces and the inherent laminar nature of microchannel *** designs of complex channel structures and three-dimensional geometries have been investigated in the past to obtain an efficient mixing in passive *** the studies on mixing enhancement with simple planar geometries of passive mixers have been few and *** present work aims to investigate the possibility of mixing enhancement by employing simple planar type designs,such as t-mixer and t–t mixer with cylindrical elements placed in the mixing *** mixing performance has been evaluated in the Reynolds number range of 6 *** results have shown that t–t mixer with cylindrical elements performed significantly well and obtained very good mixing quality over basic t-mixer for the entire range of Reynolds number(6 to 700).the device has also shown better mixing as compared to basic t–t mixer and t-mixer with cylindrical elements.A larger pair of vortices formed in the stagnation area due to the presence of a cylindrical element in the *** elements downstream caused significant enhancement in mixing due to splitting and recombining *** size of the cylindrical element in the t–t mixer has been optimized to obtain better mixing performance of the *** improvement in mixing quality by t–t mixer with cylindrical elements has been obtained at the expense of small rise in pressure drop as compared to other passive designs considered in this ***,the current design of t–t mixer with cylindrical elements can act as an effective and simple passive mixing device for various mi

关键词： CFD-simulation Cylindrical elements Micromixers Mixing quality Obstructions t–t-mixer