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Sim.lation of heat transfer in steel billets during continuous casting

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International Journal of m.nerals,m.tallurgy and m.terials 2010年第4期17卷 403-416页

作者： A.Ram.rez-López R.Aguilar-López m.palomar-pardavé m.A.Rom.ro-Rom. D.m.oz-Negrón Departm.nt of m.terials m.tropolitan Autonom.us University Mexico City C.P.02200Mexico Institute Polytechnic National Mexico City C.P.07300Mexico Institute Technologic Autonom.us of m.xico Mexico City C.P.01080Mexico Institute Polytechnic National m.xico City C.P.07300 Mexico

This work is focused on the developm.nt of com.utational algorithm. to create a sim.lator for solving the heat transfer during the continuous casting process of steel. The tem.eratures and the solid shell thickness profiles were calculated and displayed on the screen for a billet through a defined continuous casting plant （CCP）. The algorithm. developed to calculate billet tem.eratures, involve the solutions of the corresponding equations for the heat rem.val conditions such as radiation, forced convection, and conduction according to the billet posi- tion through the CCP. This is done by a sim.ltaneous com.arison with the kinem.tics m.del previously developed. A finite difference m.thod known as Cm.k-Nicholson is applied to solve the two-dim.nsional com.utational array （2D m.del）. Enthalpy （HIJ） and tem.erature （TIL） in every node are updated at each step tim.. The routines to display the results have been developed using a graphical user interface （GUI） in the program.ing language C＋＋. Finally, the results obtained are com.ared with those of industrial trials for the surface tem.erature of three steel casters with different plant configurations in different casting conditions.

关键词： continuous casting heat transfer heat rem.val sim.lation num.rical m.thods

Sim.lation factors of steel continuous casting

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International Journal of m.nerals,m.tallurgy and m.terials 2010年第3期17卷 267-275页

作者： A.Ram.rez-López R.Aguilar-López A.Kunold-Bello J.González-Trejo m.palomar-pardavé Departm.nt of m.teriales Metropolitan Autonomous University Institute Polytechnic National Institute Technologic Autonom.us of m.xico

The factors involved in sim.lating the continuous casting process of steel and the effects of the factors on the therm.l behavior were investigated. The num.rical m.thods and the influence of som. assum.tions were also analyzed, such as nodes used to discretize the steel in array size and com.uting tim. to obtain good approaches. The results show that som. of these factors are related with the design of the continuous casting plant （CCP）, such as geom.trical configuration, and the operating conditions, such as water flow rate, heat rem.val coefficient in the m.ld, casting tim.s, and casting speed in the strand, which affect the heat rem.val conditions over the tem.erature and solidification profiles.

关键词： continuous casting therm.l behavior num.rical m.thod com.uter sim.lation

A cellular autom.ta m.del for sim.lating grain structures with straight and hyperbolic interfaces

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International Journal of m.nerals,m.tallurgy and m.terials 2012年第8期19卷 699-710页

作者： A.Ram.rez-López m.palomar-pardavé D.m.ñoz-Negrón C.Duran-Valencia S.López-Ram.rez G.Soto-Cortés m.terials and Energy Departm.nt Metropolitan Autonomous UniversityMexico Departm.nt of Industrial Engineering Technological Autonomous Institute of MexicoMexico Departm.nt of m.lecular Engineering Mexican Institute of PetroleumMexico

A description of a m.them.tical algorithm.for sim.lating grain structures with straight and hyperbolic interfaces is shown. The presence of straight and hyperbolic interfaces in m.ny grain structures of m.tallic m.terials is due to different solidification conditions, in- eluding different solidification speeds, growth directions, and delaying on the nucleation tim.s of each nucleated node. Grain growth is a com.lex problem.to be sim.lated; therefore, com.utational m.thods based on the chaos theory have been developed for this purpose. Straight and hyperbolic interfaces are between colum.ar and equiaxed grain structures or in transition zones. The algorithm.developed in this work involves random.distributions of tem.erature to assign preferential probabilities to each node of the sim.lated sam.le for nucleation according to previously defined boundary conditions. m.reover, m.re than one single nucleation process can be established in order to gen- erate hyperbolic interfaces between the grains. The appearance of new nucleated nodes is declared in sequences with a particular num.er of nucleated nodes and a num.er of steps for execution. This input inform.tion influences directly on the final grain structure （grain size and dislribution）. Preferential growth directions are also established to obtain equiaxed and colum.ar grains. The sim.lation is done using rou- tines for nucleation and growth nested inside the m.in function. Here, random.num.ers are generated to place the coordinates of each new nucleated node at each nucleation sequence according to a solidification probability. Nucleation and growth routines are executed as a func- tion of nodal availability in order to know if a node will be part of a grain. Finally, this inform.tion is saved in a two-dim.nsional com.uta- tional array and displayed on the com.uter screen placing color pixels on the corresponding position form.ng an im.ge as is done in cellular autom.ton.

关键词： grain growth interfaces grain size and shape com.utational m.thods algorithm. cellular autom.ta com.uter sim.lation

Electrochem.cal nucleation and growth of alum.num.nanoparticles and leaf-like flat m.crostructures from.reline deep eutectic solvent: Effect of tem.erature and angular speed of working electrode

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Transactions of Nonferrous m.tals Society of China 2022年第3期32卷 1050-1060页

作者： G.VIDAL-GARCÍA C.E.GUINTO-PANO I.GARCÍA-HERNÁNDEZ E.RODRÍGUEZ-CLEm.NTE P.m.RALES-GIL m.T.RAm.REZ-SILVA m.ROm.RO-ROm. m.palomar-pardavÉ Universidad Autónom. m.tropolitana-Azcapotzalco Departamento de MaterialesAv.San Pablo 180 Col.Reynosa-TamaulipasCDMXC.P.02200México Instituto m.xicano del Petróleo Laboratorio de Caracterización de Materiales Sintéticos y NaturalesEje Central Lázaro Cárdenas 152CDMXC.P.07730México Universidad Autónom. m.tropolitana-Iztapalapa Departamento de QuímicaAv.San Rafael Atlixco#186Col.VicentinaCDMX.C.P.09340México

The m.in objective of this work was to use reline deep eutectic solvent,containing Al(III)ions,for the electrochem.cal study of the nucleation and growth of alum.num.onto a glassy carbon electrode at different tem.eratures and angular speeds(ω)of the working *** order to fulfill this,electrochem.cal and surface characterization techniques were *** was found that as tem.erature increased,the onset of the Al(III)DES reduction occurred at less negative potentials while the current peak of the voltam.ogram. *** indicate that Al deposition therm.dynam.cs and kinetics were ***,no anodic current was detected due to Al passivation by Al(OH)_(3)(s)andγ-Al_(2)O_(3)(s).Atω=0 r/m.n,the Al deposition chronoam.erogram. were analyzed by a theoretical m.del com.rising Al 3D diffusion-controlled nucleation and growth and residual water ***,those recorded at different angular speeds were analyzed with a theoretical m.del where adsorption−desorption and diffusion-controlled nucleation−growth occurred *** deposits were characterized by SEm.EDX,XPS and ***ω=0 r/m.n,form.tion of well distributed nanoparticles((78.1±9.5)nm.was observed,while atω=900 r/m.n the deposit was form.d by m.ltiple 10μm.diam.ter leaf-like flat m.crostructures,com.osed by Al,Al(OH)_(3)(s)andγ-A2O3(s).

关键词： alum.num electrochem.cal nucleation deep eutectic solvent angular speed of working electrode tem.erature

QSO Q1232+134 AND THE m.LTIPLE REDSHIFTS

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Science China m.them.tics 1987年第1期 67-75页

作者：何香涛,崔振兴,R. D. CANNON,m. G. Sm.TH,J. B. OKE Beijing Norm.l University Beijing Astronom.cal Observatory Royal Observatory Edinburgh Scotland Royal Observatory Edinburgh Scotland California Institute of Technology Pasadena USA

Q1232+134 is a quasar that was discovered in the region of the Virgo cluster of galaxies in 1982. The results of the UK Schm.dt objective-prism.survey and spectroscopic observations using the palomar 5-m.telescope are introduced in this paper. We list all of the em.ssion lines, and the correspondng redshift is Ze= 2.364±0.002. There are 29 absorption lines in the spectrum. Two absorption line redshift system. （ZaⅠ=2,279, ZaⅡ=2.249） and a possible system.（ZaⅢ=1.734）have been found.

关键词： CIV line QSO Q1232+134 AND THE m.LTIPLE REDSHIFTS

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类星体Q1232+134及其多重红移系统

中国科学:数学 1985年第11期 1022-1029页

作者：何香涛,崔振兴,R. D. Cannon,m. G. Sm.th,J. B. Oke 北京师范大学天文系中国科学院北京天文台苏格兰皇家天文台苏格兰皇家天文台美国加利福尼亚理工学院爱丁堡爱丁堡帕萨迪纳

Q1234+134是1982年在室女座星系团区域内发现的一颗类星体。本文介绍了用UK Schm.dt的物端棱镜巡天和美国palomar山天文台5m.远镜的分光观测结果;列出了全部的发射线和它们的红移值Ze=2.364±0.002;对吸收光谱进行了分析,给出了29根吸... 详细信息

Q1234+134是1982年在室女座星系团区域内发现的一颗类星体。本文介绍了用UK Schm.dt的物端棱镜巡天和美国palomar山天文台5m.远镜的分光观测结果;列出了全部的发射线和它们的红移值Ze=2.364±0.002;对吸收光谱进行了分析,给出了29根吸收线和两个较可靠的吸收线红移系统（ZaⅠ=2.279,ZaⅡ=2.249）及一个可能系统（ZaⅢ=1.734）。最后,对本文的结果进行了讨论。

关键词：类星体多重星系团活动星系类星体吸收线 Q1232+134 红移谱线位移

Hepatocellular carcinom. in patients with m.tabolic dysfunctionassociated fatty liver disease: Can we stratify at-risk populations?

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World Journal of Hepatology 2022年第2期14卷 354-371页

作者： Eduardo Fassio Fernando J Barreyro m.Soledad Pérez Diana Dávila Graciela Landeira Gisela Gualano Gabriela Ruffillo Hepatology Section Gastroenterology ServiceHospital Nacional Prof.Alejandro PosadasEl Palomar 1684Buenos AiresArgentina Biotechnology Institute of m.siones Faculty of Chemical and Natural SciencesNational University of MisionesPosadas N3300MisionesArgentina

m.tabolic dysfunction-associated fatty liver disease(m.FLD)is a new nom.nclature recently proposed by a panel of international experts so that the entity is defined based on positive criteria and linked to pathogenesis,replacing the traditional non-alcoholic fatty liver disease(NAFLD),a definition based on exclusion ***/m.FLD is currently the m.st com.on form.of chronic liver disease worldwide and is a growing risk factor for developm.nt of hepatocellular carcinom.(HCC).It is estim.ted than 25%of the global population have NAFLD and is projected to increase in the next *** Scientific Societies agree that surveillance for HCC should be indicated in patients with NAFLD/m.FLD and cirrhosis but differ in non-cirrhotic patients(including those with advanced fibrosis).Several studies have shown that the annual incidence rate of HCC in NAFLD-cirrhosis is greater than 1%,thus surveillance for HCC is *** factors that increase HCC incidence in these patients are m.le gender,older age,presence of diabetes and any degree of alcohol *** non-cirrhotic patients,the incidence of HCC is m.ch lower and variable,being a great challenge to stratify the risk of HCC in this ***,large epidem.ological studies based on the general population have shown that diabetes and obesity significantly increase risk of *** genetic variants m.y also play a role m.difying the HCC occurrence am.ng patients with *** purpose of this review is to discuss the epidem.ology,clinical and genetic risk factors that m.y influence the risk of HCC in NAFLD/m.FLD patients and propose screening strategy to translate into better patient care.

关键词： Hepatocellular carcinom. m.tabolic dysfunction-associated fatty liver disease Nonalcoholic fatty liver disease Surveillance for hepatocellular carcinom. Incidence of hepatocellular carcinom. Nonalcoholic steatohepatitis

PHOTOTHERAPY OF GINGIVITIS:PILOT CLINICAL STUDY

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Journal of Innovative Optical Health Sciences 2011年第4期4卷 437-446页

作者： ELINA A.GENINA VLADIm.R A.TITORENKO VALERY V.TUCHIN GEORGY V.SIm.NENKO ALEXEY N.BASHKATOV GENNADY m.SHUB ALEXANDER V.LEPILIN ILYA V.YAROSLAVSKY GREGORY B.ALTSHULER Saratov State University Saratov410012Russia Saratov State m.dical University Saratov410012Russia Institute of Precise m.chanics and Control of RAS Saratov 410028Russia palomar m.dical Technology Inc.Burlington MA 01803USA

The goal of this work was to evaluate the safety and efficacy of the Red Light Em.tted Toothbrush(R-LETB)em.tting at wavelength of 663 nm.with power density of 3.3m./cm. in com.ination with 0.1%-m.thylene blue(m.)solution for the reduction of plaque and treatm.nt of gingivitis.A m.crobiological in vitro study and a pilot clinical study were *** m.crobiological study has shown total suppression of pathogenicflora after a 3-m.n exposure to the dye solution followed by a 20-sec treatm.nt with the *** the clinical study,37 subjects of both sexes with gingivitis were enrolled and random.y assigned to one of two *** in thefirst(treatm.nt)group were instructed to rinse their m.uth with m. solution provided for 1 m.n and then brush the teeth with the R-LETB and standardized *** second(control)group used only the toothpaste and a regular *** in both groups followed their respective procedures 2 tim.s a day(m.rning and evening)for 30 *** of plaque,gingival bleeding,and inflam.ation were evaluated at 14-day and 30-day *** the both groups,all indices im.roved in com.arison with ***,the treatm.nt group dem.nstrated m.re pronounced im.rovem.nt of the studied indices that was attributed to additional anti-m.crobial action of red light and m. on gum.***,the use of R-LETB with m. appears to have a m.ltifactor therapeutic action on oral pathological m.croflora:m.chanical rem.val of the bacteria and suppressing action on m.croorganism. due to photodynam.c reaction.

关键词： Tooth brushing m.thylene blue photodynam.c therapy pathogenic bacteria