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An Overview of High-Performance Aircraft Structural Al Alloy-AA7085

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Acta Metallurgica Sinica(English Letters) 2015年第7期28卷 909-921页

作者： t.Ram Prabhu CEMILAC Defence R&D Organization

AA7085 Al alloy is a new-generation,high-strength,quench-insensitive alloy that features in airframe applications such as massive bulkhead and wing spars structures in Airbus A380 and Joint Strike Fighter *** alloy has a great potential in replacing currently used high-strength AA7 xxx alloys in many international and national military aircraft programs [Hawk,Su-30,Mi G series,light combat aircraft（tejas）,Hindustan turbo/jet trainer,light combat helicopter,advanced light helicopter,and fifth-generation fighter aircrafts].An effort has been made to highlight the processing,heat treatment,properties and applications of the AA7085 Al alloy from the existing literature on the AA7085 *** potential applications of this alloy are presented and compared with the currently used AA7075 Al alloy.A typical process cycle involved in the manufacturing of wrought AA7085 alloy products is described in ***,the precipitation mechanisms involved in the different temper conditions are critically reviewed with the supporting *** mechanical properties with a particular emphasis on tensile,fatigue,and fracture toughness properties are discussed in detail based on the analysis of experimental *** effects of temper conditions on the stress corrosion cracking and exfoliation corrosion have also been reviewed critically.

关键词： Al alloys Heat treatment Material processing Mechanical properties Corrosion

Surface Characteristics and Indentation Deformation of Porous Anodic tiO_2 Layer Before and After Hot Water treatment

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稀有金属材料与工程 2012年第S1期41卷 38-42页

作者： t Matsubara Research Institute for Applied Mechanics Kyushu UniversityFukuoka 816-8580Japan

Hot water treatment was performed to modify the surface of porous tiO2 layer prepared by anodic spark oxidation technique for better *** oxide layer without water treatment exhibited a porous surface with few nanometer features and consisted of poorly crystallized *** water treatment,the poorly crystallized oxides were transformed into crystalline anatase gradually and numerous nanoparticles formed on the oxide surface,leading to increased surface roughness at the *** indentation deformation behaviors of oxide layer before and after water treatment were investigated and *** show that under the indentation load,the untreated anodic tiO2 layer exhibited good adhesion to the *** contrast,after water treatment,apparent oxides pile-up and spallation were observed around the indentation,indicating decreased adhesion strength.

关键词： titanium anodic spark oxidation hot water treatment nanostructure indentation

Comparing the Soil Conservation Service model with new machine learning algorithms for predicting cumulative infiltration in semi-arid regions

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Pedosphere 2022年第5期32卷 718-732页

作者： Khabat KHOSRAVI Phuong t.t.NGO Rahim BARZEGAR John QUILtY Mohammad t.AALAMI Dieu t.BUI Department of Watershed Management Engineering Ferdowsi University of MashhadMashhad 93(Iran) Department of Earth and Environment Florida International UniversityMiami 33199(USA) Institute of Research and Development Duy Tan UniversityDa Nang 550000(Vietnam) Department of Bioresource Engineering McGill UniversitySte Anne de Bellevue QC H9X(Canada) Faculty of Civil Engineering University of TabrizTabriz 51(Iran) Department of Civil and Environmental Engineering University of WaterlooWaterloo N2L 3G1(Canada) Department of Business and It University of South-Eastern NorwayNotodden 3603(Norway)

Water infiltration into soil is an important process in hydrologic cycle;however,its measurement is difficult,time-consuming and *** and physical models have been developed to predict cumulative infiltration(CI),but are often *** this study,several novel standalone machine learning algorithms(M5Prime(M5P),decision stump(DS),and sequential minimal optimization(SMO))and hybrid algorithms based on additive regression(AR)(i.e.,AR-M5P,AR-DS,and AR-SMO)and weighted instance handler wrapper(WIHW)(i.e.,WIHW-M5P,WIHW-DS,and WIHW-SMO)were developed for CI *** Soil Conservation Service(SCS)model developed by the United States Department of Agriculture(USDA),one of the most popular empirical models to predict CI,was considered as a ***,154 measurements of CI(explanatory/input variables)were taken from 16 sites in a semi-arid region of Iran(Illam and Lorestan provinces).Six input variable combinations were considered based on Pearson correlations between candidate model inputs(time of measuring and soil bulk density,moisture content,and sand,clay,and silt percentages)and *** dataset was divided into two subgroups at random:70%of the data were used for model building(training dataset)and the remaining 30%were used for model validation(testing dataset).the various models were evaluated using different graphical approaches(bar charts,scatter plots,violin plots,and taylor diagrams)and quantitative measures(root mean square error(RMSE),mean absolute error(MAE),Nash-Sutcliffe efficiency(NSE),and percent bias(PBIAS)).time of measuring had the highest correlation with CI in the study *** best input combinations were different for different *** results showed that all hybrid algorithms enhanced the CI prediction accuracy compared to the standalone *** AR-M5P model provided the most accurate CI predictions(RMSE=0.75 cm,MAE=0.59 cm,NSE=0.98),while the SCS model had the lowest performance(RMSE=4.77 cm,MAE=2.64 cm,NSE=

关键词： additive regression hybrid algorithms empirical model soil water infiltration weighted instances handler wrapper

Multi-spectroscopic characterization of bovine serum albumin upon interaction with atomoxetine

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Journal of Pharmaceutical Analysis 2017年第3期7卷 148-155页

作者： Arunkumar t. Buddanavar Sharanappa t. Nandibewoor P.G. Department of studies in Chemistry Karnatak UniversityDharwad 580003India

the quenching interaction of atomoxetine(AtX) with bovine serum albumin(BSA) was studied in vitro under optimal physiological condition(pH=7.4) by multi-spectroscopic techniques. the mechanism of AtX-BSA system was a dynamic quenching process and was confirmed by the fluorescence spectra and lifetime measurements. the number of binding sites, binding constants and other binding characteristics were computed. thermodynamic parameters ΔH^0 and ΔS^0 indicated that intermolecular hydrophobic forces predominantly stabilized the drug-protein system. the average binding distance between BSA and AtX was studied by F?rsters theory. UV-absorption, Fourier transform infrared spectroscopy(Ft-IR), circular dichroism(CD), synchronous spectra and three-dimensional(3D) fluorescence spectral results revealed the changes in micro-environment of secondary structure of protein upon the interaction with AtX. Displacement of site probes and the effects of some common metal ions on the binding of AtX with BSA interaction were also studied.

关键词： Atomoxetine Bovine serum albumin 3D fluorescence spectra Ft-IR Energy transfer Lifetime measurement

Electronic structure of GaAs/A1GaAs quantum double rings in lateral electric field

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Chinese Optics Letters 2009年第10期7卷 882-885页

作者： Y.Yao t.Ochiai t.Mano t.Kuroda t.Noda N.Koguchi K.Sakoda National Institute for Materials Science University of tsukuba L-NESS Universit di Milano Bicocca

A three-dimensional model of GaAs/A1GaAs quantum double rings in the lateral static electric field is investigated theoretically. the eigenvalue problem with the effective-mass approximation is solved by means of the finite-element method. the energy levels and wave functions of quantum-confined electrons and heavy holes are obtained and show an agreement with our previous theoretical and experimental studies. It is shown in the approximation of neglecting the Coulomb attraction between the electron and heavy hole that a relatively large Stark shift of exciton emission of 4 meV is attainable with an applied electric field of 0.7 kV/cm.

关键词： GaAs Electronic structure of GaAs/A1GaAs quantum double rings in lateral electric field

Azo-bridged triazoles: Green energetic materials

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Defence technology（防务技术） 2016年第1期12卷 1-15页

作者： Lemi tüRKER Department of Chemistry Middle East Technical University

In this short review, excerpts from the literature of azo-bridged triazoles(mainly 1,2,4-triazoles), some of their derivatives(chloromethyl,dinitro and trinitro pyrazole substituted ones, etc.) and some of their salts, have been presented focusing on the most recent investigations. these classes of compounds, known as high nitrogen compounds, are generally high energy density materials. therefore, if available some of their ballistic properties were included.

关键词： Azo-bridged triazoles Energetic materials High nitrogen compounds

Flow of Oldroyd-B fluid with nanoparticles and thermal radiation

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Applied Mathematics and Mechanics(English Edition) 2015年第1期36卷 69-80页

作者： t.HAYAt t.HUSSAIN S.A.SHEHZAD A.ALSAEDI Department of Mathematics Quaid-i-Azam University Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Faculty of ScienceKing Abdulaziz University Department of Mathematics Faculty of Computing Mohammad Ali Jinnah University Department of Mathematics COMSATS Institute of Information Technology

the two-dimensional boundary layer flow of an Oldroyd-B fluid in the presence of nanoparticles is investigated. Convective heat and mass conditions are considered in the presence of thermal radiation and heat generation. the Brownian motion and thermophoresis effects are retained. the nonlinear partial differential equations are reduced into the ordinary differential equation （ODE） systems. the resulting ODE systems are solved for the series solutions. the results are analyzed for various physical parameters of interest. Numerical values of the local Nusselt and Sherwood numbers are also computed and analyzed.

关键词： nanoparticle Oldroyd-B fluid heat generation convective condition

Structural modeling of sandwich structures with lightweight cellular cores

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Acta Mechanica Sinica 2007年第5期23卷 545-559页

作者： t.Liu Z.C.Deng t.J.Lu Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China MOE Key Laboratory of Strength and Vibration School of AerospaceXi'an Jiaotong UniversityXi'an 710049China

An effective single layered finite element （FE） computational model is proposed to predict the structural behavior of lightweight sandwich panels having two dimensional （2D） prismatic or three dimensional （3D） truss cores. three different types of cellular core topology are considered： pyramidal truss core （3D）, Kagome truss core （3D） and corrugated core （2D）, representing three kinds of material anisotropy： orthotropic, monoclinic and general anisotropic. A homogenization technique is developed to obtain the homogenized macroscopic stiffness properties of the cellular core. In comparison with the results obtained by using detailed FE model, the single layered computational model can give acceptable predictions for both the static and dynamic behaviors of orthotropic truss core sandwich panels. However, for non-orthotropic 3D truss cores, the predictions are not so well. For both static and dynamic behaviors of a 2D corrugated core sandwich panel, the predictions derived by the single layered computational model is generally acceptable when the size of the unit cell varies within a certain range, with the predictions for moderately strong or strong corrugated cores more accurate than those for weak cores.

关键词： Cellular material Sandwich panel Homogenization Finite element

EFFECtS OF MAGNEtIC FIELD StRENGtH ON MICROStRUCtURE AND tEXtURE EVOLUtION IN COLD-ROLLED INtERStI-tIAL-FREE StEEL BY MAGNEtIC FIELD ANNEALING

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Acta Metallurgica Sinica(English Letters) 2008年第2期21卷 103-108页

作者： t.Watanabe Key Laboratory for Anisotropy and texture of Materials (Ministry of Education) Northeastern University

Effects of magnetic field strength on the evolution of recrystallization microstructure and recrystallization texture in cold-rolled interstitial-flee steel were investigated after annealing at 660℃ in a magnetic field up to 12 t. Magnetic annealing was found to retard recrystallization and induce recrystallized grains elongated along the magnetic field direction. An interesting phenomenon is that the magnetic field shows the strongest effect at 1 t.

关键词： Magnetic annealing Recrystallization texture Interstitial-freesteel