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Journal of Natural Gas Chemistry 2008年第4期17卷 313-320页

作者： v.H.Rane S.t.Chaudhari v.R.Choudhary Chemical Engineering and Process Development Division National Chemical Laboratory

Surface properties （viz. surface area, basicity/base strength distribution, and crystal phases） of alkali metal doped CaO （alkali metal/Ca= 0.1 and 0.4） catalysts and their catalytic activity/selectivity in oxidative coupling of methane （OCM） to higher hydrocarbons at different reaction conditions （viz. temperature, 700 and 750 ℃; CH4/O2 ratio, 4.0 and 8.0 and space velocity, 5140-20550 cm^3 ·g^-1·h^-1） have been investigated. the influence of catalyst calcination temperature on the activity/selectivity has also been investigated. the surface properties （viz. surface area, basicity/base strength distribution） and catalytic activity/selectivity of the alkali metal doped CaO catalysts are strongly influenced by the alkali metal promoter and its concentration in the alkali metal doped CaO catalysts. An addition of alkali metal promoter to CaO results in a large decrease in the surface area but a large increase in the surface basicity （strong basic sites） and the C2＋ selectivity and yield of the catalysts in the OCM process. the activity and selectivity are strongly influenced by the catalyst calcination temperature. No direct relationship between surface basicity and catalytic activity/selectivity has been observed. Among the alkali metal doped CaO catalysts, Na-CaO （Na/Ca = 0.1, before calcination） catalyst （calcined at 750 ℃）, showed best performance （C2＋ selectivity of 68.8% with 24.7% methane conversion）, whereas the poorest performance was shown by the Rb-CaO catalyst in the OCM process.

关键词： oxidative coupling of methane alkali metal doped CaO catalysts basicity/base strength distribution catalytic activity/selectivity

Exploring the electromagnetic shielding behavior of lanthanum doped calcium nanoferrites

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Journal of Rare Earths 2024年第11期42卷 2128-2136页

作者： E.Ahilandeswari K.Sakthipandi R.Rajesh Kanna G.Rajkumar B.Ganesh Babu S.Arunmetha Aslam Hossain P.Sakthivel v.Rajendran M.Srinidhi Raghavan Department of Physics SRM TRP Engineering College Department of Electronics and Communication Engineering M. Kumarasamy College of Engineering Department of Physics Easwari Engineering College Department of Mechanical Engineering SRM TRP Engineering College Centre for Advanced Energy Studies Department of Electronics and Communication EngineeringKoneru Lakshmaiah Education Foundation Smart Materials Research Institute Southern Federal University Centre for Materials Science Department of PhysicsScience and HumanitiesFaculty of EngineeringKarpagam Academy of Higher Education Centre for Nanotechnology Academy of Maritime Education and Training (Deemed to be University) Department of Chemistry and Centre for Nano-Materials and Displays B.M.S. College of Engineering

the present study focuses on the synthesis and characterization of lanthanum(La3+)-doped calcium nanoferrites(CaLaxFe2-xO4:x=0.025,0.050,0.075 and 0.100) using the sonochemical *** techniques were employed to analyze the effect of La3+infusion,Raman spectroscopy confirms the presence of active A1g,t2gand Egmodes in the CaLaxFe2-xO4nanoferrite,indicating the formation of an active ferrite *** introduction of La3+doping results in a significant increase in the band gap energy,rendering the nanoferrites insulating（3.23-3,57 ev）.At higher frequencies,the impedance studies reveal minimal losses and better AC conductivity,pointing to improved dielectric *** higher frequencies,the Q-factor of La-doped calcium nanoferrites shows lower electromagnetic *** M-H curve exhibits ferromagnetic behavior,with La3+-doped calcium nano ferrites displaying a saturation magnetization ranging from 12.72 to 18.10 emu/*** incorporation of La3+also induces enhanced electrical polarization,leading to notable dielectric loss and increased absorption of electromagnetic ***,these CaLaxFe2-xO4nanoferrites demonstrate potential as effective microwave absorbers across a wide frequency range,with significant shielding absorption observed at 8.8-9.1 GHz.

关键词： Dielectric Magnetism Microwave absorption Nanoferrites Rare earths Structural properties

Mechanical and thermal postbuckling of FGM thick circular cylindrical shells reinforced by FGM stiffener system using higher-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2017年第1期38卷 73-98页

作者： D.v.DUNG H.t.tHIEM Faculty of Mathematics Mechanics and InformaticsVietnam National UniversityHanoi 100000Vietnam

the postbuckling of the eccentrically stiffened circular cylindrical shells made of functionally graded materials （FGMs）, subjected to the axial compressive load and external uniform pressure and filled inside by the elastic foundations in the thermal environments, is investigated with an analytical method. the shells are reinforced by FGM stringers and rings. the thermal elements of the shells and stiffeners in the fundamental equations are considered. the equilibrium and nonlinear stability equations in terms of the displacement components for the stiffened shells are derived with the third-order shear deformation theory and Leckhniskii smeared stiffener technique. the closed-form expressions for determining the buckling load and postbuckling load-deflection curves are obtained with the Galerkin method. the effects of the stiffeners, the foundations, the material and dimensional parameters, and the pre-existent axial compressive and thermal load are considered.

关键词： stiffened cylindrical shell functionally graded material (FGM) postbuck- ling elastic foundation analytical

Comparative Study on the Leaching Dynamic Properties of Five Kinds of Microparticulate forms of vitamin B_1

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High technology Letters 2001年第2期7卷 1-5页

作者：吴格天 mai Kangsen Zhu Wei Aquaculture Research Laboratory College of Fisheries Ocean University of Qingdao

With an aim to reduce leaching of water soluble vitamins, the leaching properties of five kinds of microparticulate forms of vitamin B 1 are investigated by means of dynamic system. these microparticles include: alginate and alginate CMC microcapsules prepared by emulsion coacervation process (ECP), alginate and gelatin microcapsules prepared by spray drying process (SDP), and alginate microbound. the results show these five microparticulate forms of vB 1 can reduce leaching significantly compared to crystalline form vB 1, and the leaching rates at different intervals, diameters and encapsulation efficiencies ( EE ) are significantly different among all kinds of microparticles (ANOvA, P the leaching properties of the five microparticles are in accord with Higuchi equation. Based on the regression equation, the half loss time ( t 50 ) is *** conclusion, the alginate CMC microencapsule is a potential tool to reduce leaching of water soluble vitamins.

关键词： Leaching Microencapsulation Microbound vitamin B 1

Cr-doped Na_(3)v_(2)(PO_(4))_(3)@C enables high-capacity with v^(2+)/v^(5+)reaction and stable sodium storage

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Journal of Materials Science & technology 2023年第34期165卷 1-7页

作者： Bo mai Boyu Xing Yunfan Yue Nianyao Cai Congcong Cai Sitian Lian Hao Fan Mengyu Yan ting Zhu Ping Hu Xuewen Wang Liqiang mai State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Foshan Xianhu Laboratory of the Advanced Energy Science and technology Guangdong LaboratoryFoshan 528216China

Due to its abundant sodium content and low cost,sodium-ion battery(SIB)has become an effective substitute and supplement for lithium-ion batteries,which has a broad development prospect in largescale energy storage ***-super-ionic conductor(NASICON)structural materials have stable 3D skeleton structures and open Na+transport channels,which is a very promising SIB cathode *** in the typical NASICON material Na_(3)v_(2)(PO_(4))_(3)(NvP),the number of electrons involved in NvP per formula unit is less than 2 at the stable voltage window,which limits the further improvement of battery *** this work,we report another NASICON structured Na_(3)v_(4/3)Cr_(2/3)(PO_(4))_(3)@C(NvCP@C),which is obtained by Cr-doped NvP through spray *** taking full advantage of the voltage platforms of v^(5+/4+),v^(4+/3+),and v^(3+/2+)in the window of 1.5-4.4 v,NvCP@C delivered a high discharge capacity(175 mAh g^(-1))and durable cyclability(86%capacity retention for 2000 cycles).In-situ X-ray diffraction results demonstrate that the reversible structural evolution accompanies by solid-solution reaction and two-phase reaction mechanisms co-exist during charge/discharge *** coupled with Na^(+)preembedded hard carbon(HC),the assembled NvCP@C//HC full cell delivers a high capacity(105 mAh g^(-1))and long cycling performance(70%after 1000 cycles).this Cr-doped NvP method offers new insights into the design of high-energy NASICON-structured cathode materials.

关键词： Sodium-ion batteries NASICON Na_(3)v_(4/3)Cr_(2/3)(PO_(4))_(3)@C Spray drying v^(2+)/v^(5+)reaction

Electrodeposition of aluminium and aluminium-copper alloys from a room temperature ionic liquid electrolyte containing aluminium chloride and triethylamine hydrochloride

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 909-916页

作者： P.v. Suneesh t.G. Satheesh Babu t. Ramachandran Department of Sciences Amrita School of Engineering Amrita Vishwa Vidyapeetham Amritanagar P. O.Coimbatore - 641112India

the electrodeposition of A1 and A1-Cu binary alloys on to gold substrates from a room temperature ionic liquid electrolyte containing A1C13-EtaNHC1 was studied. the electrochemical behavior of the electrolyte and the mechanism of deposition were investigated through cyclic voltammetry （Cv）, and the properties of deposits obtained were assessed by scanning electron microscopy with energy dispersive X-ray spectroscopy （SEM-EDS） and X-ray diffraction （XRD）. A1 of 70μm in thickness and an A1-Cu alloy of 30μm in thickness with 8at% copper were deposited from the electrolyte. SEM images of the deposits indicate that the A1 deposit was smooth and uniform, whereas the Al-Cu deposit was nodular. the average crystalline size, as determined by XRD patterns, was found to be （30±5） and （29±5） nm, respectively, for A1 and A1-Cu alloys. Potentiodynamic polarization （tafel plots） and electrochemical impedance spectroscopic （EIS） measurements showed that Al-Cu alloys are more corrosion resistant than Al.

关键词： electrodeposition aluminium copper alloys ionic liquids triethylamine hydrochloride copper acetylacetonate

Free vibration analysis of laminated FG-CNt reinforced composite beams using finite element method

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 324-336页

作者： t.vO-DUY v.HO-HUU t.NGUYEN-tHOI Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Due Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Due Thang UniversityHo Chi Minh CityVietnam

In the present study, the free vibration of laminated functionally graded carbon nanotube reinforced composite beams is analyzed. the laminated beam is made of perfectly bonded carbon nanotubes reinforced composite (CNtRC) layers. In each layer, single-walled carbon nanotubes are assumed to be unifonnly distributed (UD) or functionally graded (FG) distributed along the thickness direction. Effective material properties of the two-phase composites, a mixture of carbon nanotubes (CNts) and an isotropic polymer, are calculated using the extended nile of mixture. the first-order shear deformation theory is used to formulate a governing equation for predicting free vibration of laminated functionally graded carbon nanotubes reinforced composite (FG?CNtRC) beams. the governing equation is solved by the finite element method with various boundary conditions. Several numerical tests are perfbnned to investigate the influence of the CNts volume fractions, CNts distributions, CNts orientation angles, boundary conditions, length-to-thickness ratios and the numbers of layers on the frequencies of the laminated FG-CNtRC beams. Moreover, a laminated composite beam combined by various distribution types of CNts is also studied.

关键词： free vibration analysis laminated FG-CNtRC beam finite element method first-order shear deformation theory composite material

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

罗汉果苷v调控高糖状态巨噬细胞M1极化促进骨髓间充质干细胞的成骨分化

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中国组织工程研究 2025年第19期29卷 3968-3975页

作者：叶枝茂惠久莹钟晓霞麦昱颖李昊广西医科大学口腔医学院/附属口腔医院口腔修复科广西壮族自治区南宁市530021 广西口腔颌面修复与重建研究重点实验室广西壮族自治区南宁市530021

背景:糖尿病微环境会造成巨噬细胞过度M1极化,这种高糖炎症状态会抑制骨髓间充质干细胞的成骨分化,从而影响糖尿病骨缺损的愈合。研究表明罗汉果苷Ⅴ具有抗炎、抗氧化、降血糖的作用,但其能否调节高糖炎症状态下巨噬细胞M1极化及骨髓间... 详细信息

背景:糖尿病微环境会造成巨噬细胞过度M1极化,这种高糖炎症状态会抑制骨髓间充质干细胞的成骨分化,从而影响糖尿病骨缺损的愈合。研究表明罗汉果苷Ⅴ具有抗炎、抗氧化、降血糖的作用,但其能否调节高糖炎症状态下巨噬细胞M1极化及骨髓间充质干细胞的成骨分化尚不清楚。目的:探讨罗汉果苷Ⅴ在高糖炎症状态下调节巨噬细胞M1型极化对骨髓间充质干细胞成骨分化的影响。方法:构建糖尿病C57BL/6小鼠模型,从正常和糖尿病小鼠分离骨髓来源巨噬细胞,分别培养于低糖和高糖培养基。使用脂多糖和干扰素γ作为炎症刺激诱导骨髓来源巨噬细胞的M1型极化,同时以160,320,640μmol/L罗汉果苷Ⅴ干预,用流式细胞术检测F4/80^(+)CD86^(+)细胞比例,qRt-PCR检测诱导型一氧化氮合酶、白细胞介素1β、白细胞介素6的mRNA表达水平,ELISA检测骨髓来源巨噬细胞上清液中肿瘤坏死因子α水平。分离C57BL/6小鼠骨髓间充质干细胞,分别使用低糖或高糖成骨诱导液诱导成骨分化,添加M1型巨噬细胞条件培养基作为炎症刺激,以及320μmol/L罗汉果苷Ⅴ干预,成骨诱导14 d后采用qRt-PCR检测碱性磷酸酶、Runt相关因子2、骨钙素、骨桥蛋白的mRNA表达水平,成骨诱导21 d后进行茜素红染色及定量分析。结果与结论:①流式细胞术结果显示320,640μmol/L罗汉果苷Ⅴ组的F4/80^(+)CD86^(+)细胞比例明显低于高糖炎症对照组(Pt-PCR结果显示160,320,640μmol/L罗汉果苷Ⅴ组的诱导型一氧化氮合酶、白细胞介素6的mRNA相对表达量较高糖炎症对照组显著降低(Pt相关因子2和骨桥蛋白的mRNA相对表达量增加(P<0.05)。结果表明,罗汉果苷Ⅴ可通过抑制高糖炎症状态下骨髓来源巨噬细胞的M1型极化及炎症因子表达,促进骨髓间充质干细胞的成骨分化。

关键词：罗汉果苷Ⅴ 巨噬细胞 M1型极化骨髓间充质干细胞炎症反应成骨分化高糖

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