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synthesis of coral-like structures of Pr-Yb co-doped YIG: structural,optical, magnetic and antimicrobial properties

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Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra s.Castro-Lopes J.Matilla-Arias Idglan s.de Lima Edson C.silva-Filho Josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDs) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against s. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

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棒与星系整体恒星形成性质关系的统计研究

天文学进展 2024年第1期42卷 115-127页

作者：穆子豪沈世银 Rafael s.de souza Ana L.Chies-santos 中国科学院上海天文台星系宇宙学重点实验室上海200030 中国科学院大学北京100049 星系和宇宙学半解析研究重点实验室上海200034 赫特福德大学天体物理研究中心英国哈特菲尔德学院巷AL109AB 南里奥格兰德州联邦大学科学研究所巴西阿雷格里港9500

盘状星系中的棒结构特征与星系自身所处环境及整体恒星形成特征之间存在复杂的相互关系。利用细致的星系形态特征测量计划Galaxy Zoo deCaLs中的数据构建了一组目前最大的具有同样恒星质量分布的强棒、弱棒和无棒星系样本。通过引入星... 详细信息

盘状星系中的棒结构特征与星系自身所处环境及整体恒星形成特征之间存在复杂的相互关系。利用细致的星系形态特征测量计划Galaxy Zoo deCaLs中的数据构建了一组目前最大的具有同样恒星质量分布的强棒、弱棒和无棒星系样本。通过引入星系所处暗晕质量及相空间特征来控制星系所处的环境效应之后,进一步对比研究强棒、弱棒和无棒星系的恒星形成特征。研究表明,有棒星系中的恒星形成熄灭的比例系统地高于无棒星系,且强棒的效应更为明显。但是,对于仍处于恒星形成主序上的星系来说,强棒、弱棒和无棒星系的恒星形成特征并没有显著差别。以上结果表明,星系中的棒特征在其存在的时标中可能使部分星系迅速地从恒星形成转入熄灭状态。

关键词：棒旋星系恒星形成环境

Artificial neural network approach for rheological characteristics of coal-water slurry using microwave pre-treatment

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International Journal of Mining science and Technology 2017年第2期27卷 379-386页

作者： B.K.sahoo s.de B.C.Meikap department of Chemical Engineering Indian Institute of Technology Research and development Centre for Iron and steel Steel Authority of India Limited Chemical Engineering School of Engineering Howard College University of Kwazulu-Natal

detailed experimental investigations were carried out for microwave pre-treatment of high ash Indian coal at high power level(900 W) in microwave oven. The microwave exposure times were fixed at60 s and 120 s. A rheology characteristic for microwave pre-treatment of coal-water slurry(CWs) was performed in an online Bohlin viscometer. The non-Newtonian character of the slurry follows the rheological model of Ostwald de Waele. The values of n and k vary from 0.31 to 0.64 and 0.19 to 0.81 Pa·sn,respectively. This paper presents an artificial neural network(ANN) model to predict the effects of operational parameters on apparent viscosity of CWs. A 4-2-1 topology with Levenberg-Marquardt training algorithm(trainlm) was selected as the controlled ANN. Mean squared error(MsE) of 0.002 and coefficient of multiple determinations(R^2) of 0.99 were obtained for the outperforming model. The promising values of correlation coefficient further confirm the robustness and satisfactory performance of the proposed ANN model.

关键词： Microwave pre-treatment Coal-water slurry Apparent viscosity Artificial neural network Back propagation algorithm

REFERENCE FUNCTIONAL AND CHARACTERIsTIC sPACE FOR LAGRANGE AND BERNsTEIN OPERATORs

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Analysis in Theory and Applications 1995年第4期11卷 6-14页

作者： s.de Marchi M.Morandi Cecchi dept. of Pure and Applied Math. Via Belzoni 7-Padova ItalyDept. of Pure and Applied Math. Via Belzoni 7-Padova Italy

This paper deals with the description and the representation of polynomials.defined over n-simplices, The polynomials are computed by using two recurrent schemes: the Neville-Aitken one for the Lagrange interpolating operator and the de Casteljau one for the Bernstein-Bezier approximating operator. Both schemes fall intothe framework of transformations of the form where the F iare given numbers (forexample, at the initial step they coincide with the values of the function on a given lattice), and the coefficients (x) are linear polynomials valued in x and x is fixed. A general theory for such sequence of transformations can be found in [2] where it is also proved that these tranformations are completely characterized in term of a linear functional, reference functional. This functional is associated with a linear space., characteristic *** concepts of reference functionals and characteristic spaces will be used and we shall prove the existence of a characteristic space for the reference functional: associated with these operators.

关键词： REFERENCE FUNCTIONAL AND CHARACTERIsTIC sPACE FOR LAGRANGE AND BERNsTEIN OPERATORs

An innovative approach for integrated airline network and aircraft family optimization

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Chinese Journal of Aeronautics 2020年第2期33卷 634-663页

作者： JoséALEXANDRE T.G.FREGNANI Bento s.de MATTOs JoséA.HERNANdes department of Aeronautical Engineering Technological Institute of Aeronautics12228-900 Sao Jose dos CamposBrazil

The determination of optimal aerial transport networks and their associated flight frequencies is crucial for the strategic planning of airlines,as well as for carrying out market research,to establish target markets,and for aircraft and crew *** addition,optimum airplane types for the selected networks are crucial to improve revenue and to provide reduced operating *** present study proposes an innovative approach to determine the optimal aerial transport network simultaneously with the determination of the optimum fleet for that network,composed of three types of airplanes(network and vehicle integrated design).The network profit is *** passenger’s.demands between the airports are determined via a gravitational *** embedded linear programming solution is responsible for obtaining potential optimal network *** optimum fleet combination is.determined from a database of candidate aircraft designs via genetic algorithm.A truly realistic airplane representation is made possible thanks to accurate surrogate models for engine and aerodynamics is *** accurate engine deck encompassing a compression map and an innovative engine weight calculation bes.des an aerodynamical artificial neural network module enable a high degree of accuracy for the mission *** proposed methodology is applied to obtain the optimum network comprised of twenty main Brazilian airports and corresponding fleet.

关键词： Air transport Aircraft design Airline economics Airline network optimization Multidisciplinary design optimization

PET-modified red mud as catalysts for oxidative desulfurization reactions

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Journal of Environmental sciences 2017年第7期29卷 312-320页

作者： Nayara T.do Prado Ana P.Heitmann Herman s.Mansur Alexandra A.Mansur Luiz C.A.Oliveira Cinthia s.de Castro department of Chemistry Federal University of Minas GeraisAv.Antonio Carlos 6627Campus Pampulha31270-901BH-MGBrazil department of Metallurgical and Materials Engineering Au.Antonio Carlos 6627Campus Pampulha31270-901BH-MGBrazil

This work describes the synthesis of catalysts based on red mud/polyethylene terephthalate（PET） composites and their subsequent heat treatment under N2 *** materials were characterized by scanning electron microscopy（sEM）,temperature programmed reduction（TPR）,Fourier transform infrared spectroscopy（FT–IR）,X-ray diffraction（XRD）,thermogravimetric（TG） analysis and N2adsorption/*** catalysts were evaluated in the oxidative desulfurization reaction of dibenzothiophene（DBT） in a biphasic *** results indicated that the PET impregnation on red mud increased the affinity of the catalyst with the nonpolar phase（fuel）,in which the contaminant was dissolved,allowing a higher conversion（up to 80%） and selectivity to the corresponding dibenzothiophene *** sulfone compound is more polar than DBT and diffused into the polar solvent as indicated by the data obtained via gas chromatography–mass spectrometry（GC–Ms）.

关键词： Red mud PET Dibenzothiophene desulfurization Dibenzothiophene sulfone

Benign intratesticular schwannoma:a rare finding

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Asian Journal of Andrology 2006年第1期8卷 101-103页

作者： Maria Chiara sighinolfi Alessandro Mofferdin stefano s.de stefani Antonio Celia salvatore Micali Giovanni saredi Giulio Rossi Riccardo Valli Giampaolo Bianchi Division of Urology Department of Pathology section of Anatomic Pathology University of Modena 41100 ModenaItaly

schwannoma is a peripheral nerve tumour, occasionally located in the genitourinary tract. We described an extremely rare case of intratesticular neurinoma in a 79-year-old patient. （Asian JAndrol 2006 Jan; 8： 101-103）

关键词： schwannoma schwann cells testicular neoplasm s 100 protein

Impedancemetry of multiplexed quantum devices using an on-chip cryogenic complementary metal-oxide-semiconductor active inductor

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Chip 2023年第4期2卷 133-141页

作者： L.Le Guevel G.Billiot s.de Franceschi A.Morel X.Jehl A.G.M.Jansen *** UniversitéGrenoble Alpes CEALETIGrenoble F-38000France UniversitéGrenoble Alpes CEAGrenoble INPIRIGPHELIQSGrenoble F-38000France department of Electrical and Computer Engineering University ofMassachusetts-AmherstMA 01003USA Universitésavoie Mont Blanc SYMMEAnnecy F-74000France

In the pursuit for scalable quantum processors,significanteffort has been devoted to the development of cryogenic classical hardware for the control and readout of a growingnumber of *** current work presented a novelapproach called impedancemetry that is suitable for measuringthe quantum capacitance of semiconductor qubits connected toa resonant *** impedancemetry circuit exploits theintegration of a complementary metal-oxide-semiconductor(CMOs)active inductor in the resonator with tunable resonance frequency and quality factor,enabling the optimizationof readout sensitivity for quantum *** realized cryogenic circuit allows fast impedance detection with a measuredcapacitance resolution down to 10 aF and an input-referrednoise of 3.7 aF/Hz *** 4.2 K,the power consumption of theactive inductor amounts to 120μW,with an additional dissipation for on-chip current excitation(0.15μW)and voltageamplification(2.9 mW)of the impedance *** to the commonly used schemes based on dispersiveRF reflectometry which require millimeter-scale passive inductors,the circuit exhibits a notably reduced footprint(50μm360μm),facilitating its integration in a scalable quantumclassical *** impedancemetry method has been applied at 4.2 K to the detection of quantum effects in the gatecapacitance of on-chip nanometric CMOs transistors that areindividually addressed via multiplexing.

关键词： Impedancemetry Qubit readout Cryogenic circuit Activeinductor CMOs

An Analytical Formulation for Pollutant Dispersion simulation in the Atmospheric Boundary Layer

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Journal of Environmental Protection 2013年第8期4卷 57-64页

作者： Glenio A.Goncalves Regis s.de Quadros Daniela Buske Federal University of Pelotas(UFPel) Department of Mathematics and Statistics(IFM/DME)PelotasBrazil

In this work we present the solution of the two-dimensional advection-diffusion equation by the GILTT method. The GILTT approach uses, in the series expansion, eigenfunctions given in terms of cosine functions. Here, a different expansion for the solution of the advection-diffusion equation will be explored. In other words, a sturm-Liouville problem carrying more information of the original problem is cons.dered, given by Bessel functions. Numerical simulations and comparisons with experimental data are presented.

关键词： Analytical solution Advection-Diffusion Equation Air Pollution Modeling Integral Transform Bessel Functions