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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

structure,magnetic and adsorption properties of novel FePt/h-BN heteromaterials

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Nano Research 2023年第1期16卷 1473-1481页

作者： Anton s.Konopatsky vladislava v.Kalinina Alena s.savchenko Denis.v.Leybo Ekaterina v.sukhanova viktor s.Baidyshev Zakhar I.Popov Andrey v.Bondarev Josef Polčák Dmitry v.shtansky National University of science and Technology(MIsIs) Leninskiy prospect 4Moscow119049Russia Emanuel Institute of Biochemical Physics RAs Kosygina 4Moscow119334Russia Katanov Khakas state University 90 Lenin pr.655017 AbakanRussia Plekhanov Russian University of Economics 36 Stremyanny per.Moscow 117997Russia Department of Control Engineering Faculty of Electrical EngineeringCzech Technical University in PragueTechnicka 2Prague 16627Czech Republic CEITEC-Central European Institute of Technology Brno University of TechnologyPurkyňova 123Brno 61200 BrnoCzech Republic

Nanomaterials with high specific surface area and high absorption capacity are attracting increased interest aimed at imparting the desired magnetic *** work is devoted to the study of the effect of heat treatment in a hydrogen atmosphere on the microstructure,adsorption and magnetic properties of heterogeneous FePt/h-BN *** via the polyol process,FePt nanoparticles(NPs)had a sizestributed over the surface of hexagonal boron nitride(h-BN)*** temperature-activated fcc→fct phase transformation in ultrafine FePt NPs has been well *** NPs act as active centers dissociating H2 molecules and transfer adsorbed hydrogen atoms to the *** functional theory(DFT)calculations also indicate that the h-BN substrate can absorb hydrogen adsorbed on the FePt *** hydrogen circulation in the FePt/h-BN system promoted the fcc→fct phase transformation and allowed to control the magnetic ***/h-BN nanomaterials also exhibited a high adsorption capacity with respect to various organic dyes.

关键词： FePt/h-BN nanomaterials polyol synthesis phase transformations magnetic properties adsorption

New Data on the Mineralogy of Chromite from the Nuggihalli schist Belt,Western Dharwar Craton,Karnataka,India:Petrogenetic Implications

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Acta Geologica sinica(English Edition) 2011年第1期85卷 107-115页

作者： Perumala v.s.RAJU Elapavalooru v.s.s.K.BABU Roland K.W.MERKLE National Geophysical Research Institute Hyderabad India(Council of Scientific and Industrial Research) Department of Geology University of Pretoria PretoriaSouth Africa

The occurrence of rhythmic layering of chromite and host serpentinites in the deformed layered igneous complexes has been noticed in the Nuggihalli schist belt （NsB） in the western Dharwar craton, Karnataka, south India. For this study, the chromitite rock samples were collected from Jambur, Tagadur, Bhakatarhalli, Ranganbetta and Byrapur in the NsB. Petrography and ore microscopic studies on chromite show intense cataclasis and alteration to ferritchromite. The ferritchromite compositions are characterized by higher Cr number （Cr/[Cr＋AI]）（0.68-0.98） and lower Mg number （Mg/[Mg＋Fe]）（0.33-0.82） ratios in ferritchromite compared to that of parent chromite. The formation process for the ferritchromite is thought to be related to the exchange of Mg, AI, Cr, and Fe between the chromite, surrounding silicates （serpentines, chlorites）, and fluid during serpentinization.

关键词： chromite ferritchromite Nuggihalli schist belt Dharwar Craton India

Influence of the safety factor profile on the particle and heat transport in the Globus-M spherical tokamak

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Plasma science and Technology 2019年第11期21卷 1-6页

作者： A YU TELNOvA G s KURsKIEv E O KIsELEv N N BAKHAREv v K GUsEv N A KHROMOv s YU MEDvEDEv v B MIINAEv I v MIROsHNIKOv M I PATROv Yu v PETROv N v sAKHAROv A D sLADKOMEDOvA P B sHCHEGOLEv v v sOLOKHA v A TOKAREv s YU TOLsTYAKOv E A TUKHMENEvA Ioffe Institute Saint-Petersburg 194021Russia Keldysh Institute Russian Academy of SciencesMoscow 125047Russia NRC'Kurchatov Institute’ Moscow 123098Russia

The advanced tokamak scenario is a promising operation scenario for ITER and fusion neutron *** this scenario the minimum value of the safety factor in the center of the plasma exceeds *** the compact spherical tokamak Globus-M,the formation of such conditions is possible with neutral beam injection at the current ramp-up *** to the slower diffusion of current inside the plasma,a zone is formed with reduced heat and particle transport across the magnetic field,which affects the temperature and density profiles of the *** leads to the peaked density profile formation and improvement of the energy confinement *** achieve a high fraction of the bootstrap current,it is necessary to increase the plasma *** the same time,the maximum allowable pressure is limited to the normalized beta limit.

关键词： advanced tokamak mode transport analysis internal transport barriers

Electrochemical synthesis of boron-containing coatings on Mg alloy for thermal neutron shielding

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Journal of Magnesium and Alloys 2023年第10期11卷 3779-3789页

作者： K.v.Nadaraia s.N.suchkov N.s.Markin I.M.Imshinetskiy s.I.Ivannikov D.v.Mashtalyar A.Yu.Ustinov s.L.sinebryukhov s.v.Gnedenkov Institute of Chemistry FEB RAs 159 Pr.100-Letiya VladivostokaVladivostok 690022Russia

The work provides the results of the one-step formation of boron-containing coatings on an Mg–Mn–Ce alloy by plasma electrolytic oxidation. The results of studies of the composition, structure and morphology of heteroxide coatings are presented. It was established that the boron is contained in the coating mainly in the form of B or B_(2)O_(3). The introduction of B changes the color of coatings, and also helps to increase their porosity. The method of determining the full cross section of the interaction of thermal neutron absorption efficiency by samples material using the installation of neutron-activation analysis based on ^(252)Cf was developed. It was shown that the introduction of boron into the formed coatings allows to increase the macroscopic cross-section of the interaction of samples with thermal neutrons by 3.8 times. This effect opens the potential for the use of synthesized material in the field of nuclear technologies and aerospace industry.

关键词： Plasma electrolytic oxidation Boron Neutron capture Neutron shielding Protective coatings

strategy for Rapid Diabetic Retinopathy Exposure Based on Enhanced Feature Extraction Processing

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Computers, Materials & Continua 2023年第6期75卷 5597-5613页

作者： v.Banupriya s.Anusuya Department of Computer science and Business systems M.Kumarasamy College of EngineeringKarur639113TamilnaduIndia Department of Information Technology Saveetha School of EngineeringSaveetha Institute of Medical and Technical SciencesSIMATSChennai602117Tamil NaduIndia

In the modern world,one of the most severe eye infections brought on by diabetes is known as diabetic retinopathy(DR),which will result in retinal damage,and,thus,lead to *** retinopathy(DR)can be well treated with early *** fundus images of humans are used to screen for lesions in the ***,detecting DR in the early stages is challenging due to the minimal ***,the occurrence of diseases linked to vascular anomalies brought on by DR aids in diagnosing the ***,the resources required for manually identifying the lesions are ***,training for Convolutional Neural Networks(CNN)is more *** proposed research aims to improve diabetic retinopathy diagnosis by developing an enhanced deep learning model(EDLM)for timely DR identification that is potentially more accurate than existing CNN-based *** proposed model will detect various lesions from retinal images in the early ***,characteristics are retrieved from the retinal fundus picture and put into the EDLM for *** dimensionality reduction,EDLM is ***,the classification and feature extraction processes are optimized using the stochastic gradient descent(sGD)*** EDLM’s effectiveness is assessed on the KAG-GLE dataset with 3459 retinal images,and results are compared over vGG16,vGG19,REsNET18,REsNET34,and *** results show that the EDLM achieves higher average sensitivity by 8.28%for vGG16,by 7.03%for vGG19,by 5.58%for ResNet18,by 4.26%for ResNet 34,and by 2.04%for ResNet 50,respectively.

关键词： Diabetic retinopathy deep learning classification retinal fundus

Recrystallization Behavior Design for Controlling Grain size in strip Rolling Process

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Journal of Iron and steel Research International 2008年第1期15卷 39-44页

作者： ZHU Guo-hui s v subramanian school of Materials science and Engineering Anhui University of Technology Ma＇anshan 243002 Anhui China Department of Materials science and Engineering McMaster University Hamilton LSS 4A7 Ontario Canada

To promote effectively dynamic recrystallization and obtain a homogeneous distribution of ultrafine grain size in strip finish rolling process,the behavior of static and dynamic recrystallization must be appropriately designed to provide an ultrafine austenite microstructure without mixed grain *** design of rolling schedule was analyzed based on the control of the recrystallization behavior to achieve ultrafine grain size in the strip rolling process of niobium microalloyed *** experimental simulations were presented to validate the twice dynamic recrystallization design to achieve ultrafine grain size control.

关键词： twice dynamic recrystallization critical strain dynamic recrystallization ultrafine grain size

Molecular dynamics modeling framework for overcoming nanoshape retention limits of imprint lithography

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Microsystems & Nanoengineering 2018年第1期4卷 370-379页

作者： Anshuman Cherala s.v.sreenivasan NAsCENT Center MERB 1.206EPickle Research CampusUniversity of Texas10100 Burnet RoadAustinTX 78758USA

Complex nanoshaped structures(nanoshape structures here are defined as shapes enabled by sharp corners with radius of curvature<5 nm)have been shown to enable emerging nanoscale applications in energy,electronics,opti... 详细信息

Complex nanoshaped structures(nanoshape structures here are defined as shapes enabled by sharp corners with radius of curvatureve been shown to enable emerging nanoscale applications in energy,electronics,optics,and *** nanoshaped fabrication at high throughput is well beyond the capabilities of advanced optical *** the highest-resolution e-beam processes(Gaussian beam tools with non-chemically amplified resists)can achievesolution,this is only available at very low ***-area e-beam processes,needed for photomasks and imprint templates,are limited to~18 nm half-pitch lines and spaces and~20 nm half-pitch hole *** nanoimprint lithography,we have previously demonstrated the ability to fabricate precise diamond-like nanoshapes with~3 nm radius corners over large *** exemplary shaped silicon nanowire ultracapacitor device was fabricated with these nanoshaped structures,wherein the half-pitch was 100 *** device significantly exceeded standard nanowire capacitor performance(by 90%)due to relative increase in surface area per unit projected area,enabled by the *** beyond the previous work,in this paper we explore the scaling of these nanoshaped structures to 10 nm half-pitch and *** these scales a new“shape retention”resolution limit is observed due to polymer relaxation in imprint resists,which cannot be predicted with a linear elastic continuum *** all-atom molecular dynamics model of the nanoshape structure was developed here to study this shape retention phenomenon and accurately predict the polymer *** atomistic framework is an essential modeling and design tool to extend the capability of imprint lithography to sub-10 nm *** framework has been used here to propose process refinements that maximize shape retention,and design template assist features(design for nanoshape retention)to achieve targeted nanoshapes.

关键词： shape shaped corners

A robust composite wide area control of a DFIG wind energy system for damping inter-area oscillations

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Protection and Control of Modern Power systems 2020年第1期5卷 280-289页

作者： Ayyarao s.L.v.Tummala Department of EEE GMR Institute of TechnologyRajam 532127India

This paper presents a novel composite wide area control of a DFIG wind energy system which combines the Robust Exact Differentiator(RED)and Discontinuous Integral(DI)control to damp out inter-area *** generates the real-time differentiation of a relative speed signal in a noisy environment while DI control,an extension to a twisting algorithm and PID control,develops a continuous control signal and hence reduces *** proposed control is robust to disturbances and can enhance the overall stability of the *** proposed composite sliding mode control is evaluated using a modified benchmark two-area power system model with wind energy *** results under various operating scenarios show the efficacy of the proposed approach.

关键词： DFIG Wide area control Wind energy system sliding mode control

Boundedness of Maximal Operators and Potential Operators on Carleson Curves in Lebesgue spaces with variable Exponent

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Acta Mathematica sinica,English series 2008年第11期24卷 1775-1800页

作者： v.KOKILAsHvILI s.sAMKO A. Razmadze Mathematical Institute International Black Sea University Georgia University of Algarve Portugal

We prove the boundedness of the maximal operator Mr in the spaces L^p（·）（Г,p） with variable exponent p（t） and power weight p on an arbitrary Carleson curve under the assumption that p（t） satisfies the log-condition on Г. We prove also weighted sobolev type L^p（·）（Г, p） → L^q（·）（Г, p）-theorem for potential operators on Carleson curves.

关键词： weighted generalized Lebesgue spaces variable exponent singular operator fractional integrals sobolev theorem