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Journal of Materials Science & Technology 2021年第28期87卷 196-206页

作者： A.G.Mochugovskiy n.Yu.Tabachkova M.Esmaeili Ghayoumabadi V.V.Cheverikin A.V.Mikhaylovskaya national University of Sciences and Technology“MISIS” 119049Leninskiy Ave.4MoscowRussia Prokhorov General Physics Institute of the russian Academy of Sciences MoscowRussia

Dispersoid hardening is a key factor in increasing the recrystallization resistance and mechanical strength of non-heat treatable aluminum-based *** and Zr are the main elements that form dispersoids in commercial Al-based *** this work,the annealing-induced precipitation behavior,the grain structure,and the mechanical properties of Al-3.0 Mg-1.1 Mn and Al-3.0 Mg-1.1 Mn-0.25 Zr alloys were *** microstructure and the mechanical properties were significantly affected by annealing regimes after casting for both *** research demonstrated a possibility to form high-density distributed quasicrystalline-structured I-phase precipitates with a mean size of 29 nm during low-temperature annealing of as-cast *** manganese-bearing precipitates of I-phase increased recrystallization resistance and significantly enhanced the mechanical strength of the alloys *** estimated strengthening effect owing to I-phase precipitation was 150 *** to the formation of L1_(2)-structured Al3Zr dispersoids with a mean size of 5.7 nm,additional alloying with Zr increased yield strength by about 90 *** L1_(2)-phase strengthening effect was estimated through the dislocation bypass looping and shearing mechanisms.

关键词： Aluminum alloy Quasicrystals Dispersoid hardening recrystallization Mechanical properties

Imaging the influence of oxides on the electrostatic potential of photovoltaic InP nanowires

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nano research 2021年第11期14卷 4087-4092页

作者： Lukas Hrachowina Xianshao Zou Yang Chen Yuwei Zhang Enrique Barrigón Arkady Yartsev Magnus T.Borgström nanoLund Lund UniversityBox 11822100LundSweden Divison of Solid State Physics Lund UniversityBox 11822100LundSweden Divison of Chemical Physics Lund UniversityBox 12422100LundSweden Toyota Technological Institute NagoyaAichi 468-8511Japan

nanowires require surface passivation due to their inherent large surface to volume ratio. We investigate the effect of embedding InP nanowires in different oxides with respect to surface passivation by use of electron beam induced current measurements enabled by a nanoprobe based system inside a scanning electron microscope. The measurements reveal remote doping due to fixed charge carriers in the passivating PO_(x)/Al_(2)O_(3) shell in contrast to results using SiO_(x). We used time-resolved photoluminescence to characterize the lifetime of charge carriers to evaluate the success of surface passivation. In addition, spatially resolved internal quantum efficiency simulations support and correlate the two applied techniques. We find that atomic-layer deposited PO_(x)/Al_(2)O_(3) has the potential to passivate the surface of InP nanowires, but at the cost of inducing a field-effect on the nanowires, altering their electrostatic potential profile. The results show the importance of using complementary techniques to correctly evaluate and interpret processing related effects for optimization of nanowire-based optoelectronic devices.

关键词： InP nanowires oxides MOVPE electron beam induced current(EBIC) time-resolved photoluminescence(TrPL) field-effect

Enhancing Hyper-Spectral Image Classification with reinforcement Learning and Advanced Multi-Objective Binary Grey Wolf Optimization

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Computers, Materials & Continua 2024年第6期79卷 3469-3493页

作者： Mehrdad Shoeibi Mohammad Mehdi Sharifi nevisi reza Salehi Diego Martín Zahra Halimi Sahba Baniasadi TheWPI Business School Worcester Polytechnic InstituteWorcesterMassachusetts01609-2280USA Department of Industrial Engineering Iran University of Science and TechnologyNarmakTehran16846-13114Iran ETSI de Telecomunicación Universidad Politécnica de MadridAv.Complutense 30Madrid28040Spain Department of Civil and Environmental Engineering University of MarylandCollege ParkMaryland20742USA Department of Industrial Engineering College of EngineeringUniversity of HoustonHoustonTexas77204USA

Hyperspectral(HS)image classification plays a crucial role in numerous areas including remote sensing(rS),agriculture,and the monitoring of the *** band selection in HS images is crucial for improving the efficiency and accuracy of image *** process involves selecting the most informative spectral bands,which leads to a reduction in data *** on these key bands also enhances the accuracy of classification algorithms,as redundant or irrelevant bands,which can introduce noise and lower model performance,are *** this paper,we propose an approach for HS image classification using deep Q learning(DQL)and a novel multi-objective binary grey wolf optimizer(MOBGWO).We investigate the MOBGWO for optimal band selection to further enhance the accuracy of HS image *** the suggested MOBGWO,a new sigmoid function is introduced as a transfer function to modify the wolves’*** primary objective of this classification is to reduce the number of bands while maximizing classification *** evaluate the effectiveness of our approach,we conducted experiments on publicly available HS image datasets,including Pavia University,Washington Mall,and Indian Pines *** compared the performance of our proposed method with several state-of-the-art deep learning(DL)and machine learning(ML)algorithms,including long short-term memory(LSTM),deep neural network(Dnn),recurrent neural network(rnn),support vector machine(SVM),and random forest(rF).Our experimental results demonstrate that the Hybrid MOBGWO-DQL significantly improves classification accuracy compared to traditional optimization and DL ***-DQL shows greater accuracy in classifying most categories in both datasets *** the Indian Pine dataset,the MOBGWO-DQL architecture achieved a kappa coefficient(KC)of 97.68%and an overall accuracy(OA)of 94.32%.This was accompanied by the lowest root mean square error(rMSE)of 0.94,indicating very precise

关键词： Hyperspectral image classification reinforcement learning multi-objective binary grey wolf optimizer band selection

Prediction of COVID-19 Cases Using Machine Learning for Effective Public Health Management

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Computers, Materials & Continua 2021年第3期66卷 2265-2282页

作者： Fahad Ahmad Saleh n.Almuayqil Mamoona Humayun Shahid naseem Wasim Ahmad Khan Kashaf Junaid Department of Computer Sciences Kinnaird College for WomenLahore54000Pakistan Department of Information Systems College of Computer and Information SciencesJouf UniversitySakakaAljouf72341Saudi Arabia Division of Computer Science&Information Technology University of EducationLahore54000Pakistan School of Computer Science National College of Business Administration&EconomicsLahore54000Pakistan Department of Clinical Laboratory Sciences College of Applied Medical SciencesJouf UniversitySakakaAljouf72341Saudi Arabia

COVID-19 is a pandemic that has affected nearly every country in the *** present,sustainable development in the area of public health is considered vital to securing a promising and prosperous future for ***,widespread diseases,such as COVID-19,create numerous challenges to this goal,and some of those challenges are not yet *** this study,a Shallow Single-Layer Perceptron neural network(SSLPnn)and Gaussian Process regression(GPr)model were used for the classification and prediction of confirmed COVID-19 cases in five geographically distributed regions of Asia with diverse settings and environmental conditions:namely,China,South Korea,Japan,Saudi Arabia,and *** environmental and non-environmental features were taken as the input dataset,and confirmed COVID-19 cases were taken as the output dataset.A correlation analysis was done to identify patterns in the cases related to fluctuations in the associated *** results of this study established that the population and air quality index of a region had a statistically significant influence on the ***,age and the human development index had a negative influence on the *** proposed SSLPnn-based classification model performed well when predicting the classes of confirmed *** training,the binary classification model was highly accurate,with a root Mean Square Error(rMSE)of ***,the results of the regression analysis using the GPr technique with Matern 5/2 were highly accurate(rMSE=0.95239)when predicting the number of confirmed COVID-19 cases in an ***,dynamic management has occupied a core place in studies on the sustainable development of public health but dynamic management depends on proactive strategies based on statistically verified approaches,like Artificial Intelligence(AI).In this study,an SSLPnn model has been trained to fit public health associated data into an appropriate class,allowing GPr to predict the number of confir

关键词： Public health sustainable development artificial intelligence SArSCoV-2 shallow single-layer perceptron neural network binary classification gaussian process regression

Analysis of Power in an Argon Filled Pulsed Dielectric Barrier Discharge

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Plasma Science and Technology 2013年第7期15卷 635-639页

作者： U.n.PAL Pooja GULATI ram PrAKASH Mahesh KUMAr V.SrIVASTAVA S.KOnAr Microwave Tubes Division CSIR-Central Electronics Engineering Research Institute (CSIR-CEERI)Pilani Rajasthan-333031 India Birla Institute of Technology (BIT) Mesra Ranchi Jharkhand-835215 India

In this paper an argon filled coaxial dielectric barrier discharge （DBD） has been studied to understand the detail of power transfer from a unipolar square pulse to plasma during discharge. A dielectric barrier discharge based diffuse pulse discharge and its electrical charac-teristics are investigated. A quartz coaxial DBD tube filled at different pressures is used in the experiment. A unipolar pulse voltage of different peak voltages and frequencies has been applied to the discharge electrodes for the generation of microdischarges. Two current pulses are used for two consecutive discharges per applied voltage pulse. The second discharge, which occurs at the falling flank of the voltage pulse, is induced by the charges stored on the dielectric barrier during the first discharge. It has been deduced that the power supplied to ignite the first discharge is partly stored to ignite the second discharge when the applied voltage decays. This process ul- timately leads to much improved power transfer to the plasma. The knowledge obtained from dynamic processes of the DBDs in the discharge gap explains quantitatively the mechanism of ignition, development and extinction of the DBDs.

关键词： DBD non-equilibrium plasma non-thermal plasma diffuse pulse discharge,microdischarges

new luminescent 10-oxybenzoquinolate complexes of rare earth metals

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Journal of rare Earths 2023年第8期41卷 1135-1143,I0001页

作者： Tatyana V.Balashova Svetlana K.Polyakova Vasily A.Ilichev Andrey A.Kukinov roman V.rumyantcev Georgy K.Fukin Ivan D.Grishin Artem n.Yablonskiy Alexander F.Shestakov Mikhail n.Bochkarev G.A.razuvaev Institute of Organometallic Chemistry of russian Academy of Sciences Tropinina Street49603950Nizhny NovgorodRussian Federation nizhny novgorod State University Gagarina Avenue 23/2603950Nizhny NovgorodRussian Federation Institute for Physics of Microstructures of russian Academy of Sciences Akademicheskaya Street 7603950Nizhny NovgorodRussian Federation Institute of Problems of Chemical Physics of russian Academy of Sciences Academician Semenov Avenue1ChernogolovkaMoscow Region142432Russian Federation

A series of Sc,Y,Ce,Pr,nd,Sm,Eu,Gd,Tb,Ho,Er,Tm and Yb complexes with oxybenzoquinoline ligands(BQ) was synthesized by the reactions of 10-hydroxybenzo[h]quinoline with cyclopentadienides or tris(trimethylsilyl)amides of rare earth *** structure,as well as the photo-and electroluminescent(PL,EL) properties of these complexes in solutions and solid state were *** solutions,complexes of sodium and lanthanides exhibit double peaked ligand-centered PL of enol and keto forms of BQ with a quantum yield of 1%-8%.In the solid state the complexes of Sm,Eu,Ho,nd,Er,and Yb along with the ligand-centered PL also exhibit a moderate-intensity metal-centered PL which is characteristic of the corresponding Ln^(3+) ***(BQ)_(3) complex shows bright green EL which has intensity comparable to the best results observed for scandium complexes with other organic ligands.

关键词： Lanthanides Photoluminescence(PL) Electroluminescence(EL) 10-hydroxybenzo[h]quinoline X-ray structure Organic light-emitting diodes(OLEDs)

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内分泌性眼眶病的磁共振诊断

放射学实践 1991年第4期6卷 181-185页

作者： n.Hosten Ch.Schubert M.Cordes r.Schneider r.Felix 储凤梧 radiologische Klinik und Poliklinik des Universit tsklinikums rudolf Virchow/Charlottenburg der Freien Universit t Berlin 上海第六人民医院

磁共振断层摄影应用的指征范围随着经验的不断增加而扩大.这是对CT检查的重要补充,它能对组织进行鉴别.内分泌性眼眶病就是一个例证.

关键词：内分泌性眼眶病磁共振成象诊断

Modelling of Edge Plasma on JT-60U Tokamak by Using SOLPS5.0 Code

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Plasma Science and Technology 2011年第3期13卷 302-306页

作者：陈一平 H. KAWASHIMA n. ASAKUrA K. SHIMIZU H. TAKEnAGA Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China Japan Atomic Energy Agency Naka-shi Ibaraki-Ken 311-0193 Japan

The edge transport code SOLPS5.0 is used to model edge plasmas in the experi- mental shots on JT-60U and the profiles of the transverse particle and heat transport coefficients D, Xe and Xi along the outer midplane are obtained by fitting the simulational results to the experimental data in L-mode shot 39090 and H-mode shots 37851, 37856. The modelling and fitting results show that within the pedestal region in H-mode shots 37851 and 37856 the radial particle transport coefficient D exhibits a significant drop, but, for L-mode shot 39090, the obvious drop in both D and Xe was not found.

关键词： SOLPS5.0 JT-60U modelling

Effects of Different Types of Sludge on Soil Microbial Properties:A Field Experiment on Degraded Mediterranean Soils

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Pedosphere 2010年第6期20卷 681-691页

作者： D.TArrASón G.OJEDA O.OrTIZ J.M.ALCAIZ Centre for Ecological research and Forestry Applications Autonomous University of Barcelona IMAr-Coimbra Interdisciplinary Centre Department of ZoologyUniversity of Coimbra

The recycling of suitable organic wastes can enhance soil fertility via effects on soil physical, chemical and biological properties. To compare the effects of digested (DS), thermally dried (TDS) and composted dewatered (CDS) sewage sludge on soil microbiological properties, an experiment was conducted at field sites for more than one year (401 d) when applied to two Mediterranean degraded soils (loam and loamy sand soils). All three types of sewage sludge had a significant effect on measured parameters. In a short time, the plots of both loamy sand and loam soils amended with TDS showed the highest microbial basal respiration (loam soil: P nd soil: P nd carbon mineralization coefficient (loam soil: P nd soil: P rthermore, on loamy sand soil, the plots amended with TDS showed the highest microbial metabolic quotient (qCO 2 ) (P revealed that the addition of sludge caused transient non-equilibrium effects on almost all soil microbial properties. However, there were no differences one year later because the remaining organic carbon was stable and quite similar in all treatments. These results may have practical implications for the rehabilitation of degraded soils.

关键词： basal respiration composted sludge soil microbial biomass thermally dried sludge

Calorimetric Determination of Enthalpy of Formation of natural Gas Hydrates

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Chinese Journal of Chemical Engineering 2003年第3期11卷 276-279页

作者：高军 Kenneth n.Marsh Department of Chemical and Pharmaceutical Engineering Qingdao Institute of Chemical TechnologyQingdao 266042China Department of Chemical and Processing Engineering University of CanterburyChristchurchNew Zealand

This paper reports the measurements of enthalpies of natural gas hydrates in typical natural gas mixture containing methane, ethane, propane and iso-butane at pressure in the vicinity of 2000 kPa (300 psi) and 6900 kPa(1000psi). The measurements were made in a multi-cell differential scanning calorimeter using modified high pressure cells. The enthalpy of water and the enthalpy of dissociation of the gas hydrate were determined from the calorimeter response during slow temperature scanning at constant pressure. The amount of gas released from the dissociation of hydrate was determined from the pumped volume of the high pressure pump. The occupation ratio (mole ratio) of the water to gas and the enthalpy of hydrate formation are subject to uncertainty of 1.5%.The results show that the enthalpy of hydrate formation and the occupation ratio are essentially independent of pressure.

关键词： enthalpy of formation calorimetric determination natural gas hydrate