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Journal of Hydrodynamics 2012年第6期24卷 888-898页

作者： GU Ji-jun AN Chen LEVI carlos SU Jian Ocean Engineering Program COPPEUniversidade Federal do Rio de Janeiro Nuclear Engineering Program COPPEUniversidade Federal do Rio de Janeiro

The Generalized Integral Transform Technique （GITT） was applied to predict dynamic response of Vortex-Induced Vibration （VIV） of a long flexible cylinder. A nonlinear wake oscillator model was used to represent the cross-flow force acting on the cylinder, leading to a coupled system of second-order Partial Differential Equations （PDEs） in temporal variable. The GITT approach was used to transform the system of PDEs to a system of Ordinary Differential Equations （ODEs）, which was numerically solved by using the Adams-Moulton and Gear method （DIVPAG） developed by the International Mathematics and Statistics Library （IMSL）. Numerical results were presented for comparison to those given by the finite difference method and experimental results, allowing a critical evaluation of the technique performance. The influence of variation of mean axial tension induced by elongation of flexible cylinder was evaluated, which was shown to be not negligible in numerical simulation of VIV of a long flexible cylinder.

关键词： Vortex-Induced Vibration (VIV) nonlinear wake oscillator flexible cylinder integral transform

Influence of V(C,N) Precipitates on Microstructure and Mechanical Properties of Continuous Cooled C-Mn-V

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Journal of Iron and Steel Research International 2011年第S1期18卷 266-270页

作者： carlos Garcia-Mateo carlos Capdevila Juan Cornide Jesus Chao Francisca G Caballero carlos Garcia de Andres Materalia Research Group Department of Physical Metallurgy Centro Nacional de Investigaciones Metalúrgicas (CENIM-CSIC)Avda.Gregorio del Amo8 E-28040 MadridSpain

The effect of chemical composition and processing parameters on the formation of acicular ferrite and/or bainite has been *** particular,this paper deals with the influence that N through its combination with V,as V(C,N) precipitates,has on the decomposition of ***,the intragranular nucleation potency of V(C,N) precipitates is analyzed through the continuous cooling transformation diagrams (CCT) of two C-Mn-V steels with different contents of *** reported in this work allow us to conclude that acicular ferrite can only be achieved alloying with vanadium and nitrogen,meanwhile bainite is promoted in steels with a low level of *** is concluded that higher strength values are obtained in acicular ferrite than in bainitic steel but a similar brittle-ductile transition temperature (BDT),and lower values of impact absorbed energy (KV) has been recorded in nitrogen-rich steel.

关键词： acicular ferrite bainite vanadium precipitates mechanical properties

Optimization of an innovative approach involving mechanical activation and acid digestion for the extraction of lithium from lepidolite

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 11-19页

作者： Nathalia Vieceli carlos A.Nogueira Manuel F.C.Pereira Fernando O.Durao carlos Guimaraes Fernanda Margarido Center for Innovation Technology and Po icy Research-IN+Instituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal LNEG-Laborat6rio Nacional de Energia e Geologia I.P.Campus do Lumiar1649-038 LisboaPortugal CERENA-Centro de Recursos Naturais e Ambiente DECivilInstituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal

The recovery of lithium from hard rock minerals has received increased attention given the high demand for this element. There- fore, this study optimized an innovative process, which does not require a high-temperature calcination step, for lithium extraction from le- pidolite. Mechanical activation and acid digestion were suggested as crucial process parameters, and experimental design and re- sponse-surface methodology were applied to model and optimize the proposed lithium extraction process. The promoting effect of amorphi- zation and the formation of lithium sulfate hydrate on lithium extraction yield were assessed. Several factor combinations led to extraction yields that exceeded 90%, indicating that the proposed process is an effective approach for lithium recovery.

关键词： lepidolite lithium mechanical activation acid digestion optimization extraction

Lid scrubbing with a gel combining natural extracts for dry eye treatment

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International Journal of Ophthalmology(English edition) 2023年第7期16卷 1053-1059页

作者： Blanca Diaz-Vega carlos Rodriguez-Fabuel Sofia Vitores-Mate carlos Carpena-Torres Gran Visión Oftalmología Madrid 28026Spain e-Health Vision Department of OphthalmologyMadrid 28232Spain Gran Óptica Madrid Department of Dry EyeMadrid 28026Spain Ocupharm Research Group Department of Optometry and VisionFaculty of Optics and OptometryComplutense University of MadridMadrid 28037Spain

AIM:To evaluate the effect of lid scrubbing using a gel combining different natural extracts on ocular signs and symptoms of dry eye ***:A retrospective study was performed on 19 dry eye patients(51.1±16.0y).Non-invasive tear break-up time,tear meniscus height,meibomian gland loss,lipid layer thickness,conjunctival redness,corneal staining,ocular surface disease index(OSDI),and ocular pain intensity were measured before(baseline),1wk,and 2mo after lid scrubbing with a gel containing different natural extracts(okra extract,aloe vera leaf juice,hydrolysed soy protein,caffeine,citrus unshiu peel extract,and raspberry seed oil).RESULTS:Compared with the baseline,there was a statistically significant improvement in both first(P=0.048)and average(P=0.026)non-invasive tear break-up time 2mo after treatment,as well as in corneal staining(P=0.043,0.012),OSDI(P<0.001),and ocular pain intensity(P<0.001)after 1wk and *** addition,there was no correlation between ocular signs and ***:The lid scrubbing with a gel combining different natural extracts show beneficial effects on tear film stability,corneal damage,and ocular symptoms,which is the reason why this therapeutic procedure is proposed as an alternative for dry eye ***,it is not possible to attribute this beneficial effect solely to the presence of the natural extracts in the gel,primarily due to the absence of a negative control group.

关键词： lid hygiene natural extracts okra aloe vera soy dry eye

Impact of radiative cooling on the energy performance of courtyards in Mediterranean climate

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Building Simulation 2024年第9期17卷 1491-1513页

作者： carlos-Antonio Domínguez-Torres Antonio Domínguez-Delgado Escuela Técnica Superior de Arquitectura Universidad de SevillaAv.de Reina Mercedes241012 SevillaSpain Department of Applied Mathematics 1 Escuela Técnica Superior de ArquitecturaUniversidad de SevillaAv.de Reina Mercedes241012 SevillaSpain

Radiative cooling has proven to be a useful tool to address the problems of lack of comfort and excessive energy consumption in situations of high temperatures,overheating and heat ***,incorporating courtyards in warm climate zones has been found to be highly beneficial in addressing similar ***,there is interest in analyzing the combined effects of both:radiative cooling and *** paper presents an analysis of the impact of the application of radiative cooling on a courtyard using a comprehensive simulation approach that includes a CFD model for the thermodynamic airflow in the adjacent roofs and inside the courtyard,equations for the transient heat conduction through roofs,walls and courtyard slabs,and a hybrid raytracing-radiosity model for the evaluation of the solar radiation reaching the building surfaces and its reflections,both of specular and diffuse origin,and for the calculation of the thermal radiation exchange,especially with the *** results show that in the hot season,the courtyard with radiative cooling always provides lower temperatures than the initial courtyard does,with a temperature range of 18.33℃to 33.78℃,compared to a range of 19.32℃to 38.00℃in the initial courtyard,and producing a greater difference with outdoor temperatures that can reach 12℃versus 8℃for the reference *** addition,it was found that the courtyard with radiative cooling is able to significantly reduce the observed nighttime overheating by providing lower temperatures than the outdoor temperatures in the 50%of the nights *** was also found that the thermal loads to achieve indoor thermal comfort in the spaces adjacent to the courtyard were reduced by 63.46%to 69.85%.

关键词： radiative cooling passive cooling CFD three-dimensional modeling energy saving thermal comfort

Less is more:dimensionality reduction as a general strategy for more precise luminescence thermometry

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Light(Science & Applications) 2022年第9期11卷 2127-2139页

作者： ERVING XIMENDES RICCARDO MARIN LUIS DIAS carlos DANIEL JAQUE NanoBIG Departamento de Fisica de MaterialesFacultad de CienciasUniversidad Autónoma de MadridC/Francisco Tomás y Valiente 7Madrid 28049Spain NanoBIG Instituto Ramón y Cajal de Investigación Sanitaria(IRYCIS)Ctra.Colmenar km.9.100Madrid 28034Spain Phantom-g CICECO-Aveiro Institute of MaterialsDepartment of PhysicsUniversity of AveiroAveiro 3810-193Portugal

Thermal resolution(also referred to as temperature uncertainty)establishes the minimum discernible temperature change sensed by luminescent thermometers and is a key figure of merit to rank *** has been done to minimize its value via probe optimization and correction of readout artifacts,but little effort was put into a better exploitation of calibration *** this context,this work aims at providing a new perspective on the definition of luminescence-based thermometric parameters using dimensionality reduction techniques that emerged in the last *** application of linear(Principal Component Analysis)and non-linear(t-distributed Stochastic Neighbor Embedding)transformations to the calibration datasets obtained from rare-earth nanoparticles and semiconductor nanocrystals resulted in an improvement in thermal resolution compared to the more classical intensity-based and ratiometric ***,in turn,enabled precise monitoring of temperature changes smaller than 0.1℃.The methods here presented allow choosing superior thermometric parameters compared to the more classical ones,pushing the performance of luminescent thermometers close to the experimentally achievable limits.

关键词： precise dimensionality luminescence

Repurposing drugs to target nonalcoholic steatohepatitis

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World Journal of Gastroenterology 2019年第15期25卷 1783-1796页

作者： Silvia Sookoian carlos J Pirola Department of Clinical and Molecular Hepatology National Scientific and Technical Research Council (CONICET) University of Buenos Aires Institute of Medical Research (IDIM) Department of Molecular Genetics and Biology of Complex Diseases National Scientific and Technical Research Council (CONICET) University of Buenos Aires Institute of Medical Research (IDIM)

Nonalcoholic fatty liver disease(NAFLD) is a complex disorder that has evolved in recent years as the leading global cause of chronic liver damage. The main obstacle to better disease management pertains to the lack of approved pharmacological interventions for the treatment of nonalcoholic steatohepatitis(NASH) and NASH-fibrosis-the severe histological forms. Over the past decade,tremendous advances have been made in NAFLD research, resulting in the discovery of disease mechanisms and novel therapeutic targets. Hence, a large number of pharmacological agents are currently being tested for safety and efficacy. These drugs are in the initial pharmacological phases(phase 1 and 2),which involve testing tolerability, therapeutic action, and pharmacological *** is thus reasonable to assume that the next generation of NASH drugs will not be available for clinical use for foreseeable future. The expected delay can be mitigated by drug repurposing or repositioning, which essentially relies on identifying and developing new uses for existing drugs. Here, we propose a drug candidate selection method based on the integration of molecular pathways of disease pathogenesis into network analysis tools that use OMICs data as well as multiples sources, including text mining from the medical literature.

关键词： Drug discovery Drug repositioning Fibrosis Genetics Treatment Systems biology

A building energy models calibration methodology based on inverse modelling approach

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Building Simulation 2022年第11期15卷 1883-1898页

作者： Vicente Gutiérrez González carlos Fernández Bandera Installations construction and structuresSchool of ArchitectureUniversity of NavarraCampus UniversitarioPamplona31009NavarraSpain

Nowadays,building energy models(BEMs)are widely used,particularly in the assessment of energy consumption in buildings to address the potential savings that can be *** realisation of a dynamic energy model based on high-fidelity physics(white-box models)requires a tuning process to fit the model to reality,due to many uncertainties *** some research trends try to reduce this performance gap by modulating different types of experimental parameters such as:capacitances or *** EnergyPlus simulation software,in its latest versions,has implemented an object:HybridModel:Zone that calculates the infiltration and internal mass of buildings using an inverse modelling approach that employs only the measured indoor temperature data to invert the heat balance equation for the zone under *** main objective of this paper is to reduce the execution time and uncertainties in the development of quality energy models by generating a new calibration methodology that implements this *** uses,as a starting point,a research created by the authors of this study,which was empirically and comparatively validated against the energy models developed by the participants in Annex *** is also worth highlighting the empirical validation of the HybridModel:Zone object,since it was activated in all scenarios where its execution is possible:periods of seven days or more of free oscillation and periods in which the building is under *** findings are *** data generated with the new methodology,if compared with those produced by the baseline model,improve their resemblance to the real ones by 22.9%.While those of its predecessor did it by 15.6%.For this study,the two dwellings foreseen in Annex 58 of the IEA ECB project have been modelled and their real monitoring data have been used.

关键词： internal thermal mass energy simulation EnergyPlus inverse model Annex 58 infiltration

Kinetic approach to the study of froth flotation applied to a lepidolite ore

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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 731-742页

作者： Nathália Vieceli Fernando O.Durao carlos Guimaraes carlos A.Nogueira Manuel F.C.Pereira Fernanda Margarido Center for Innovation Technology and Policy Research-IN+Instituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal CERENA-Centro de Recursos Naturais e Ambiente DECivilInstituto Superior TecnicoUniversity of Lisbon1049-001 LisboaPortugal LNEG-Laboratorio Nacional de Energia e Geologia I.P.Campus do Lumiar1649-038 LisboaPortugal

The number of published studies related to the optimization of lithium extraction from low-grade ores has increased as the demand for lithium has grown. However, no study related to the kinetics of the concentration stage of lithium-containing minerals by froth flotation has yet been reported. To establish a factorial design of batch flotation experiments, we conducted a set of kinetic tests to determine the most selective alternative collector, define a range of pulp p H values, and estimate a near-optimum flotation time. Both collectors（Aeromine 3000 C and Armeen 12D） provided the required flotation selectivity, although this selectivity was lost in the case of pulp p H values outside the range between 2 and 4. Cumulative mineral recovery curves were used to adjust a classical kinetic model that was modified with a non-negative parameter representing a delay time. The computation of the near-optimum flotation time as the maximizer of a separation efficiency（SE） function must be performed with caution. We instead propose to define the near-optimum flotation time as the time interval required to achieve 95%–99% of the maximum value of the SE function.

关键词： lepidolite lithium ore treatment froth flotation kinetic analysis

Effects of precipitation changes on the dynamics of sparse elm woodland in Northeastern China

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BIOCELL 2018年第2期42卷 61-66页

作者： Yi TANG carlos Alberto BUSSO School of Life Science Liaoning UniversityNo.66 Chongshan RoadShenyang(C.P.110036)Liaoning ProvinceChina Departamento de Agronomía-CERZOS(CONICET) Universidad Nacional del Sur8000 Bahía BlancaArgentina

Elm(Ulmus pumila L.)is the dominant tree species in the sparse elm woodland,the original vegetation in the Horqin Sandy *** effects of changes in precipitation on *** trees have not been fully *** determined a dynamic model by considering the five stages in the *** life cycle,***,seedling,and juvenile,mature and over-mature tree *** effects of changes in precipitation on population density and age structure were then *** density,after averaging all study developmental morphology stages,ranged from 16.67 individuals/m2 to 25.01 individuals/m2 under a mean annual precipitation(MAP)of 80%to 120%,*** suggests that population density could increase as MAP also *** proportion of seedlings,and juvenile,mature and over-mature trees were 95.23%,4.58%,0.19%and 0.01%,respectively,under all precipitation *** indicates that precipitation had little effects on the developmental stages of the studied *** populations in the Horqin Sandy *** water supply might be provided in addition to the natural rainfall that occurs in the region,for contributing to maintain *** population density in the Horqin Sandy Land.

关键词： Population density Precipitation Semi-arid lands System dynamics model