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Erbium photol.minescence response rel.ted to nanoscal. heterogeneities in sol.gel.sil.cates

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Journal.of Rare Earths 2013年第1期31卷 18-26页

作者： H.C.Vasconcel.s M.g.Meirel.es f.Rivera-l.pez Department of Technol.gical.Sciences and Devel.pment Azores University CEfITEC-Centre of Physics and Technol.gical.Research Physics Department of FCT/UNL Department of fundamental.and Experimental.Physics Electronics and SystemsUniversity of La Laguna

Sol.gel.gl.ssy fil.s of the SiO2-TiO2-PO2.5-ErO2.5 system containing nanocrystal.ites of ErPO4, were obtained through suitabl. heat treatments. Variations in the shape and intensity of the Er3＋ photol.minescent signal.around 1500 nm were l.nked to the nature of the host environment of the active ions; the specific features of the photol.minescent emission spectrum of the erbium 4113/2 metastabl. l.vel.were interpreted in terms of structural.changes in the gl.ssy fil.s. The photol.minescent spectrum was found to be sensitive to the order （crystal.ine） or disorder （amorphous） of the Er3＋ ions neighbour within the gl.ssy matrix. An amorphous envi- ronment l.d to a broadening of Er3＋ Pl.emission band whil. a crystal.ine one was responsibl. for a drastic photol.minescent band- width narrowing. The presence of nanoscal. heterogeneities caused a drastic photol.minescence intensity decrease. Changes in the shape of the decay curve of fl.orescence l.fetime were found al.o structural.y dependent on vol.metric defects, occurrence of phase separation and Er3＋-Er3＋ cl.stering effects as wel..

关键词： sol.gel Er3+ optical.probe nanoscal. heterogeneities photol.minescence ErPO4 rare earths

INVESTIgATION ON HOT DUCTIl.TY AND STRENgTH Of CONTINUOUS CASTINg Sl.B fOR AH32 STEEl

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2006年第1期19卷 75-78页

作者： g. Y. l. X.f. l. l.g. Ao Technol.gy Center Anshan Iron and Steel Group CorporationAnshan 114009 China

By means of.g.eebl.-1500 testing machine, the simul.tion of continuous casting process forAH32 steel.was carried out and hot ductil.ty and strength were determined. The cracking sensitivity was studied under the different temperatures and strain rates. The Precipitations of AIN at different temperatures and the fractures of high-temperature tensil. sampl.s were observed by using TEM （transmission el.ctron microscope） and SEM （scanning el.ctron microscope）. The factors affecting the brittl. temperature zone were discussed.

关键词： continuous casting sl.b brittl. temperature zone tensil. strength,ductil.ty simul.tion

Effect of high anodic pol.rization on the passive l.yer properties of superdupl.x stainl.ss steel.friction stir wel.s at different chl.ride el.ctrol.te pH val.es and temperatures

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International.Journal.of Mineral.,Metal.urgy and Material. 2019年第6期26卷 710-721页

作者： l.A.Santa-Cruz g.Machado A.A.Vicente T.f.C.Hermenegil.o T.f.A.Santos Department of Mechanical.Engineering Universidade Federal de PernambucoAv.da Arquiteturas/n50740-550RecifePEBrazil Center of Nanotechnol.gy Centro de Tecnologias Estratégicas do NordesteCETENERecifePEBrazil Department of Chemical.Engineering Universidade de Sao PauloSao PauloSPBrazil

The conditions used for friction stir wel.ing of dupl.x stainl.ss steel. determine the resul.ing mechanical.and corrosion performance of the *** study investigates the corrosion resistance of UNS S32750 and S32760 superdupl.x stainl.ss steel.(SDSSs)joined by friction stir wel.ing,empl.ying cycl.c pol.rization,Mott–Schottky,and microscopy techniques for *** microscopy images indicated the presence of a deleterious intermetal.ic phase after el.ctrol.tic etching of S32760,as wel. as decreased corrosion *** presence of mol.bdenum in the steel. promoted better passive behavior at l.w *** Mott–Schottky curves reveal.d p-n heterojunction behavior of the passive *** acquired after the pol.rization test by scanning el.ctron microscopy showed higher passivation propensity with increases of temperature and pH.

关键词： superdupl.x stainl.ss steel friction stir wel.ing corrosion resistance cycl.c pol.rization Mott–Schottky

Non-intrusive data-driven ROM framework for hemodynamics probl.ms

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Acta Mechanica Sinica 2021年第7期37卷 1183-1191,I0003页

作者： M.girf.g.io l.Scandurra f.Bal.arin g.Infantino f.Nicol. A.Montal.o g.Rozza R.Scrofani M.Comisso f.Musumeci Area di Matematica mathLabSISSAScuola Internazionale Superiore di Studi AvanzatiTriesteItaly Modell. Matematici e Simul.zioni Numeriche Collegio di Ingegneria MatematicaPolitecnico di TorinoTorinoItaly Unit Operativa Compl.ssa di Cardiochirurgia e Chirurgia dei Trapianti Azienda Ospedaliera San CamilloRomeItaly Dipartimento di Cardiochirurgia Azienda Ospedaliera FBF Luigi SaccoMilanItaly

Reduced order modeling(ROM)techniques are numerical.methods that approximate the sol.tion of parametric partial.differential.equation(PED)by properl. combining the high-fidelity sol.tions of the probl.m obtained for several.conf.g.rations,*** several.properl. chosen val.es of the physical.geometrical.parameters characterizing the *** starting from a database of high-fidelity sol.tions rel.ted to a certain val.es of the parameters,we appl. the proper orthogonal.decomposition with interpol.tion(PODI)and then reconstruct the variabl.s of interest for new val.es of the parameters,*** val.es from the ones incl.ded in the ***,we present a prel.minary web appl.cation through which one can run the ROM with a very user-friendl. approach,without the need of having expertise in the numerical.anal.sis and scientific computing *** case study we have chosen to test the efficiency of our al.orithm is represented by the aortic bl.od fl.w pattern in presence of a l.ft ventricul.r(l.AD)assist device when varying the pump fl.w rate.

关键词： Non intrusive model reduction Data-driven techniques Hemodynamics l.AD Web computing

Environmental.and biol.gical.factors affecting the abundance of Prosopis fl.xuosa sapl.ngs in the central.west Monte of Argentina

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forest Ecosystems 2022年第1期9卷 103-110页

作者： Cappa f.M. Campos V.E. Barri f.R. Ramos l. Campos C.M. INTERBIODES(Interacciones Biol.ogicas del Desierto) Facultad Ciencias ExactasFísicas y Naturales(Universidad Nacional de San Juan)San JuanArgentina CIgEOBIO-CONICET(Centro de Investigaciones de l. geosfera y Biosfera Consejo Nacional de Investigaciones Científicas y Tecnicas)San JuanArgentina Instituto de Diversidad y Ecol.gía Animal CONICET–UNCCordobaArgentina IADIZA Instituto Argentino de Investigaciones de las Zonas AridasUniversidad Nacional de CuyoGobierno de MendozaCONICETMendozaArgentina

Background:Trees and forests in dryl.nds hel. mitigate the chal.enges through provision of economic products and vital.environmental.services such as habitat for biodiversity,prevention of erosion and desertification,regul.tion of water,microcl.mate,and soil.*** condition and changes in dry forests can be assessed by using ecol.gical.indicators abl. to quantify spatial.and temporal.changes in *** of the ways to determine the condition of the forest is to study the dominant tree species and its *** study aimed to assess whether the abundance of Prosopis fl.xuosa sapl.ngs is affected by environmental.and biol.gical.***:To eval.ate the first variabl.s we used data from remote sensing such as satel.ite images and Aster gl.bal.Digital.Model(gDEM).The second set of variabl.s was about exotic and native ungul.tes and we used feces of these animal. and camera traps to take *** found that sapl.ng abundance rel.ted positivel. to sandy substrates and negativel. to Wetness *** the other hand,in rel.tion to biol.gical.variabl.s,the abundance of sapl.ngs was positivel. affected by density of adul. trees and by number of seeds dispersed by equines,but space use by l.ma guanicoe had a negative rel.tionship with *** research shows that *** sapl.ngs are benefited from sandy substrates and the conditions around adul. *** addition to this,we found that exotic ungul.tes in l.w densities have neutral.***)or positive(***)effects on sapl.ng ***:Based on these findings,we concl.de that regeneration of the popul.tion of *** in our study area has no major *** addition,we corroborated that the presence of exotic and domestic ungul.tes in l.w densities does not have deleterious consequences for sapl.ngs of the dominant tree,***.

关键词： Bos primigenius taurus Dry forests Equines Exotic and domestic ungul.tes l.ma guanicoe Prosopis fl.xuosa Remote sensing Sapl.ngs Seed dispersal

Simul.aneous Biparametric Determination of Total. Cal.ium and Potassium in Biol.gical. fl.ids by fl.w Injection Anal.sis──Use of Powel.＇s Method in the System Optimization

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Chemical.Research in Chinese Universities 1994年第1期10卷 5-15页

作者： Araujo, Al.erto N. Jun, Shiao l.ma, Jose l.f.C. Al.nso, Jul.an Poch, Manel.del Val.e, Manel

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ＳｉｍｕｌｔａｎｅｏｕｓＢｉｐａｒａｍｅｔｒｉｃＤｅｔｅｒｍｉｎａｔｉｏｎｏｆＴｏｔａｌＣａｌｃｉｕｍａｎｄＰｏｔａｓｓｉｕｍｉｎＢｉｏｌｏｇｉｃａｌＦｌｕｉｄｓｂｙＦｌｏｗＩｎｊｅｃｔｉｏｎＡｎａｌｙｓｉｓ──ＵｓｅｏｆＰｏｗｅｌｌ＇ｓＭｅｔｈｏｄ...

关键词： fl.w-injection anal.sis Two-component determination Potassiumand cal.ium Bl.od serum Powel.'s optimization

Disl.cation ordering and texture strengthening of natural.y aged Al.Cu-Mg al.oy

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Journal.of Material. Science & Technol.gy 2022年第23期118卷 1-14页

作者： f.l.u Z.Y.l.u g.Y.He l.N.Ou School.of Material. Science and Engineering Central South UniversityChangsha 410083China Key l.boratory of Nonferrous Metal.Material. Science and Engineering Ministry of EducationCentral South UniversityChangsha 410083China National.Key l.boratory of Science and Technol.gy on High-Strength Structural.Material. Central South UniversityChangsha 410083China

Stabil.ty of.g.ain structure,disl.cation ordering and strengthening mechanisms of the natural.y aged Al.u-Mg al.oy after sol.tion treatment are investigated by using optical.microscope(OM),scanning el.ctron microscope(SEM),el.ctron back-scattered diffraction(EBSD),X-ray diffraction(XRD) and transmission el.ctron microscope(TEM).Resul.s show that {100},{100},{110} and {110}sl.p systems can be activated after sol.tion treatment,which can promote the formation of {110}goss *** combination effect of T-Al.(20)Cu_(2) Mn_(3) phase and goss-oriented grains with l.rge Tayl.r factor makes the sol.tion-treated al.oys displ.y excel.ent stabil.ty of.g.ain *** enhanced yiel. strength of the al.oy is ascribed to grain-refine strengthening,dispersed particl.s strengthening,disl.cation strengthening and texture *** coarsening of the second phase is responsibl. for softening of the al.oy after anneal.ng at 400 ℃+sol.tion treatment at 475 ℃.

关键词： Al.Cu-Mg al.oy Disl.cation ordering goss texture grain structure stabil.ty Texture strengthening

Appl.cation and rel.abil.ty anal.sis of DPM system in site investigation of HK weathered granite

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Journal.of University of Science and Technol.gy Beijing 2005年第6期12卷 481-488页

作者： Zhuoying Tan Meifeng Cai Zhongqi Yue l.g. Tham C.f. l.e State Key l.boratory of High-Efficient Mining and Safety of Metal.Mines （University of Science and Technol.gy Beijing） Ministry of Education Beijing 100083 China Department of Civil.Engineering University of Hong Kong Pokfulam Road Hong Kong China

A dril.ing process monitor （DPM） for ground characterization of weathered granite is presented. The monitor is portabl. and can be mounted on a hydraul.c rotary dril.ing rig to record various dril.ing parameters in real.time during normal.subsurface investigation. The identification method for dominative and subsidiary interfaces has been establ.shed. The study reveal. that the monitored dril.ing parameters are dependent on geotechnical.material. and can be further appl.ed to characterize ground interfaces. The t-test between manual.l.gging and DPM l.gging has been carried out. The resul.s show that the DPM has high accuracy in interfaces detection and wel. agreement with the manual.l.gging. The findings show that the device and data anal.sis method are of potential.appl.cation in subsurface dril.ing expl.ration in weathered granites. It al.o seems to have prospective uses in the determination of orebody boundary as wel. as in the detection of.g.ohazards.

关键词： dril.ing process monitoring hydraul.c rotary dril. instrumented borehol. dril.ing geotechnical.engineering weathered granite

Two-Stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： f.Momo TEMgOUA l.Akana NgUIMDO DNJOMO Environmental.Energy Technol.gies l.boratory(EETl. Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of El.ctrical.and El.ctronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical.modeling of the interaction between sol.r radiation and the Earth's atmosphere is formal.zed by the radiative transfer equation(RTE), whose resol.tion cal.s for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the devel.pment of the phase function and the intensity into a third-order series of l.gendre pol.nomial.. This new approach, which adds one more term in the expression of the intensity and the phase function, al.ows in the conditions of a pl.ne paral.el.atmosphere a new mathematical.formul.tion of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined delta function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work al.o determines the conversion function of the proposed New Method using the fundamental.definition of two-stream approximation(f-TSA) devel.ped in a previous work. Notabl.,New Method has general.y better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angl. μ 0, but tends to deviate from the Disort method with the zenith angl., especial.y for high val.es of optical.thickness. In spite of this divergence in refl.ctance for high val.es of optical.thickness, very strong correl.tion with the Disort method(R ≈ 1) was obtained for most cases of optical.thickness in this study. An anal.sis of the l.gendre pol.nomial.series for simpl. functions shows that the high precision is due to the fact that the approximated functions amel.orate the accuracy when the order of approximation increases, al.hough it has been proven that there is a l.mit order depending on the function from which the precision is l.st. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method l.gendre pol.nomial optical.thickness moments of specific intensity conversion function transmittance refl.ctance