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Combustion Synthesis of Ti-2B-Cu/Ni and 3Ti-2BN-Cu/Ni Bilayered Cermets

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Journal of Materials Science & Technology 2003年第4期19卷 355-359页

作者： WeipingShEN WenbinCAO ChangchunGE E.h.grigoryan A.E.Sytschev A.S.Rogachev Lab.ofSpecialCeramics&p/M UniversityofScienceandTechnologyBeijingBeijing100083China InstituteofStructureMacrokinetics RussianAcademyofSciencesChernogolovka142432Russia

The effects of Cu and Ni (x=0, 10, 20 and 40 wt pet) and compaction pressures (12, 24, 84 and 108 Mpa) on combustion wave velocity and wave front shape for Ti-2B-Cu/Ni and 3Ti-2BN-Cu/Ni bilayered cermets were investigated by a video camera. Since the boiling point of Cu is lower, the wave velocities of specimens are slower. Due to the higher specific heat of Ni than that of Cu, the wave velocities of specimens was slowed down a lot with increasing the Ni diluent. The wave velocity differences of the specimens containing Ni are more than that of the bilayered specimens containing Cu. Wave velocities of the specimens containing Ni increased more than that of the specimens containing Cu when higher pressure was employed for green mixture. The more the wave velocity difference of the bilayer, the more curved the specimen.

关键词： Combustion synthesis Functionally graded material Cermet

Dielectric studies of binary mixtures of ethylene glycol mono phenyl ether with 1-butanol at different temperatures

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Journal of Advanced Dielectrics 2017年第4期7卷 10-16页

作者： h.A.Chaube V.A.Rana Department of physics School of Sciences Gujarat UniversityAhmedabad 380009 GujaratIndia

Static permittivity(ε),refractive index(n)and density(ρ)of binary mixtures of ethylene glycol mono phenyl ether(EGMpE)with 1-butanol(1-BuOh)over the entire range of mole fraction and at temperatures(T=303:15,313.15 and 323.15 K)have been *** the experimental data,parameters such as excess static permittivity(ε^(E)),excess permittivity at optical frequency(ε^(E)_(∞)),effective Kirkwood correlation factor(g^(eff)),corrective Kirkwood correlation factor(g^(f))and Bruggeman factor(f^(b))have been calculated to obtain qualitative and quantitative information about the complex formation through h-bond in binary *** order to predict the static permittivity of polar–polar binary mixtures six mixing rules were applied and for refractive index five mixing rule were *** results of permittivity(ε)and refractive index(n)are compared with those obtained from theoretical *** parameters were fitted to the Redlich–Kister type polynomial equation.

关键词： Static permittivity refractive index Kirkwood correlation factor permittivity models refractive index models Redlich-Kister equation

ON BEST SIMULTANEOUS AppROXIMATION IN QUOTIENT SpACES

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Analysis in Theory and Applications 2007年第1期23卷 35-49页

作者： M. Iranmanesh h. Mohebi University of Kerman

We assume that X is a normed linear space, W and M are subspaces of X. We develop a theory of best simultaneous approximation in quotient spaces and introduce equivalent assertions between the subspaces W and W ＋ M a... 详细信息

关键词： quotient space best simultaneous approximation simultaneous pseudo-Chebyshev simultaneous quasi-Chebyshev simultaneous weakly-Chebyshev

A new classification for the family graphidaceae(Ascomycota:Lecanoromycetes:Ostropales)

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Fungal Diversity 2012年第1期52卷 107-121页

作者： Eimy Rivas plata Robert Lücking h.Thorsten Lumbsch Department of Biological Sciences University of Illinois-Chicago845 West Taylor Street(MC 066)ChicagoIL 60607USA Department of Botany The Field Museum1400 South Lake Shore DriveChicagoIL 60605-2496USA

A revised classification for the emended family graphidaceae is proposed,based on recent phylogenetic studies,including the finding that three previously separated families(Asterothyriaceae,Gomphillaceae,Thelotremataceae)are nested within graphidaceae and in part *** family comprises three major clades which are here delimited as subfamilies Fissurinoideae,Gomphilloideae,and *** latter is composed of three major clades which are formally delimited as tribes graphideae,Ocellularieae,and *** addition,three new genera are described to accommodate the Ocellularia clandestina(Clandestinotrema)group,the Ocellularia cruentata group(Cruentotrema)and Myriotrema pycnoporellum(pycnotrema).

关键词： Asterothyriaceae Classification Gomphillaceae Thelotremataceae

Existence of Nonabelian Free Subgroups in the Maximal Subgroups of GLn（D）

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Algebra Colloquium 2014年第3期21卷 483-496页

作者： h.R. Dorbidi R. Fallah-Moghaddam M. Mahdavi-hezavehi Department of Mathematical Sciences Sharif University of 3bchnology P.O. Box 11155-3415 Tehran Iran

Given a non-commutative finite dimensional F-central division algebra D, we study conditions under which every non-abelian maximal subgroup M of CLn （D） contains a non-cyclic free subgroup. In general, it is shown that either M contains a non-cyclic free subgroup or there exists a unique maximal subfield K of Mn（D） such that NCLn（D）（K＊） = M, K＊ △ M, K/F is Galois with Gal（K/F） ≌ M/K＊, and F[M] = in（D）. In particular, when F is global or local, it is proved that if （[D ： F], Char（F）） = 1, then every non- abelian maximal subgroup of GL1 （D） contains a non-cyclic free subgroup. Furthermore, it is also shown that GLn（F） contains no solvable maximal subgroups provided that F is local or global and n ≥ 5.

关键词： free subgroup maximal subgroup central simple algebralotion

Estimation of Tsunami Run-up height by Three Artificial Neural Network Methods

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China Ocean Engineering 2009年第1期23卷 85-94页

作者： Nuray GEDIK Emel IRTEM h.Kerem CIGIZOGLU M.Sedat KABDASLI Department of Civil Engineering Balikesir University Division of hydraulics Civil Engineering FacultyIstanbul Technical University

Tsunami ran-up height is a significant parameter for dimensions of coastal structures. In the present study, tsunami run-up heights are estimated by three different Artificial Neural Network （ANN） models, i.e. Feed Forward Back propagation （FFBp）, Radial Basis Functions （RBF） and Generalized Regression Neural Network （grNN）. As the input for the ANN configuration, the wave height （h） values are employed. It is shown that the tsunami ran-up height values are closely approximated with all of the applied ANN methods. The ANN estimations are slightly superior to those of the empirical equation. It can be seen that the ANN applications are especially significant in the absence of adequate number of laboratory experiments. The results also prove that the available experiment data set can be extended with ANN simulations. This may be helpful to decrease the burden of the experimental studies and to supply results for comparisons.

关键词： tsanami run-up height artificial neural network methods experiments

Binary titanium alloys as dental implant materials—a review

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Regenerative Biomaterials 2017年第5期4卷 315-323页

作者： Xiaotian Liu Shuyang Chen James K.h.Tsoi Jukka pekka Matinlinna Department of Orthodontics Tianjin Stomatological Hospital of Nankai UniversityTianjinP.R.China Dental Materials Science Faculty of DentistryThe University of Hong KongPrince Philip Dental Hospital34 Hospital RoadHong Kong SARP.R.China Department of prosthodontics Tianjin Stomatological Hospital of Nankai UniversityTianjinP.R.China

Titanium(Ti)has been used for long in dentistry and medicine for implant *** the years,not only the commercially pure Ti but also some alloys such as binary and tertiary Ti alloys were *** aim of this review is to describe and compare the current literature on binary Ti alloys,including Ti-Zr,Ti-In,Ti-Ag,Ti-Cu,Ti-Au,Ti-pd,Ti-Nb,Ti-Mn,Ti-Mo,Ti-Cr,Ti-Co,Ti-Sn,Ti-Ge and Ti-Ga,in particular to mechanical,chemical and biological parameters related to implant *** was searched using the pubMed and Web of Science databases,as well as google without limiting the year,but with principle key terms such as‘Ti alloy’,‘binary Ti’,‘Ti-X’(with X is the alloy element),‘dental implant’and‘medical implant’.Only laboratory studies that intentionally for implant or biomedical applications were *** to available literatures,we might conclude that most of the binary Ti alloys with alloyingpd,Nb,Mn,Cr,Mo,Sn and Co have high potential as implant materials,due to good mechanical performance without compromising the biocompatibility and biological behaviour compare to cp-Ti.

关键词： binary Ti Ti alloy dental implant biocompatibility

Novel Framework of Segmentation 3D MRI of Brain Tumors

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Computers, Materials & Continua 2023年第2期74卷 3489-3502页

作者： Ibrahim Mahmoud El-henawy Mostafa Elbaz Zainab h.Ali Noha Sakr Department of Computer Science Faculty of Computers and InformaticsZagazig UniversityZagazigEgypt Department of Computer Science Faculty of Computers and InformaticsKafrelsheikh UniversityKafrelsheikhEgypt Department of Embedded Network Sys.and Tec. Faculty of Artificial IntelligenceKafrelsheikh UniversityKafrelsheikhEgypt Computers Engineering and Control Systems Department Faculty of EngineeringMansoura UniversityMansouraEgypt

Medical image segmentation is a crucial process for computer-aided diagnosis and *** image segmentation refers to portioning the images into small,disjointed parts for simplifying the processes of analysis and *** and speckle noise are different types of noise in magnetic resonance imaging(MRI)that affect the accuracy of the segmentation process ***,image enhancement has a significant role in MRI *** paper proposes a novel framework that uses 3D MRI images from Kaggle and applies different diverse models to remove Rician and speckle noise using the best possible noise-free *** proposed techniques consider the values of peak Signal to Noise Ratio(pSNR)and the level of noise as inputs to the attention-U-Net model for segmentation of the *** framework has been divided into three stages:removing speckle and Rician noise,the segmentation stage,and the feature extraction *** framework presents solutions for each problem at a different stage of the *** the first stage,the framework uses Vibrational Mode Decomposition(VMD)along with Block-matching and 3D filtering(Bm3D)algorithms to remove the ***,the most significant Rician noise-free images are passed to the three different methods:Deep Residual Network(DeRNet),Dilated Convolution Auto-encoder Denoising Network(Di-Conv-AE-Net),andDenoising Generative Adversarial Network(DGAN-Net)for removing the speckle *** Bm3D have achieved pSNR values for levels of noise(0,0.25,0.5,0.75)for reducing the Rician noise by(35.243,32.135,28.214,24.124)and(36.11,31.212,26.215,24.123)*** framework also achieved pSNR values for removing the speckle noise process for each level as follows:(34.146,30.313,28.125,24.001),(33.112,29.103,27.110,24.194),and(32.113,28.017,26.193,23.121)forDeRNet,Di-Conv-AE-Net,and DGAN-Net,*** experiments that have been conducted have proved the efficiency of the proposed framework a

关键词： MRI Rician noise speckle noise segmentation deep learning

Spatial Distribution of Magnetic properties and Selected heavy Metals in Calcareous Soils as Affected by Land Use in the Isfahan Region,Central Iran

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pedosphere 2012年第1期22卷 33-47页

作者： Z. DANKOUB S. AYOUBI h. KhADEMI LU Sheng-Gao Department of Soil Science College of Agriculture Isfahan University of Technology Isfahan 84156-83111 （Iran） College of Environmental and Resource Sciences Zhejiang University Hangzhou 310000 （China）

Anthropogenic activities have caused the accumulation of heavy metals in the soil environment. pollution of the soils significantly reduces environmental quality and affects human health. In many recent studies, magnetic susceptibility ts have been used for pollution monitoring. The objective of this research was to determine the spatial variability of magnetic properties and selected heavy metals and the effect of land use on their variability in the surface soils of the Isfahan region, Central Iran. A total of 158 composite surface （0-5 cm） samples of calcareous soils were collected from an area of about 700 km2, located along a cross-border transect from Isfahan City to a steel plant, covering urban, industrial, agricultural, and uncultivated land uses. Concentrations of copper （Cu）, zinc （Zn）, lead （pb）, manganese （Mn）, iron （Fe）, nickel （Ni）, chromium （Cr）, and cobalt （Co） and magnetic parameters, magnetic susceptibility at low frequency （xlf）, natural remanent magnetization （NRM）, saturation isothermal remanent magnetization （SIRM）, and isothermal remanent magnetization at the field of 100 mT （IRM100mT） and the backfield of 100 mT （IRM-100mT）, were measured in all the soil samples. Results showed that magnetic susceptibility in the urban and industrial land topsoils （0-5 cm） samples was significantly higher than that in the agricultural and uncultivated land soils in the study area. Concentrations of Cu, Zn, pb, Mn, and Fe were positively correlated with magnetic properties （xlf, IRM100mT, SIRM, IRM-100mT, and NRM）, which could be attributed to their inputs from traffic emissions and industrial activities at the study sites. Ni and Cr concentrations showed significant negative correlations with magnetic properties. No significant correlation was found between Co concentration and magnetic parameters. The Tomlinson pollution load index （pLI） showed significant correlation with the magnetic properties （xlf, IRM100mT, SIRM, IRM-100mT, and NRM）. The spatial distri

关键词： anthropogenic activities contaminated soils magnetic susceptibility pollution load index proxy measure