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Landesman–Lazer Type Conditions and Multiplicity Results for Nonlinear Elliptic Problems with Neumann Boundary Values

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Acta Mathematica sinica,English series 2014年第2期30卷 229-250页

作者： Edcarlos Domingos DA sILVA francisco Odair DE PAIVA Universidade Federal de Gois Departamento de Matemtica Universidade Federal de so Carlos Departamento de Matemtica

We establish the existence and multiplicity of solutions for steklov problems under non- resonance or resonance conditions using variational methods. In our main theorems, we consider a weighted eigenvalue problem of ... 详细信息

关键词： Neumann-steklov eigenvalue problems resonance Landesman-Lazer conditions

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

Assisted Natural Remediation of a Trace Element-Contaminated Acid soil:An Eight-Year Field study

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Pedosphere 2015年第2期25卷 250-262页

作者： Jian XIONG Paula MADEJON Engracia MADEJON francisco CABRERA Instituto de Recursos Naturales y Agrobiologia de sevillaIRNAs CSICAvenida Reina Mercedes10P.O.Box 1052Seville 41080 Spain

There are many remediation techniques for organic contaminated soils,but relatively few of them are applicable to trace elementcontaminated soils.A field experiment was carried out to investigate assisted natural remediation(ANR) of an acid soil contaminated by As,Cd,Cu,Zn and Pb using one inorganic amendment,sugar beet lime(sL),and two organic amendments,biosolid compost(BC)and leonardeite(LE).The experiment was arranged in a completely randomized block design with four treatments in three replicates:1) a non-amended control(NA);2) sL amended at 30 Mg ha^(-1) year^(-1);3) BC amended at 30 Mg ha^(-1) year^(-1) and 4) LE amended at 20 Mg ha^(-1) year^(-1) plus sL amended at 10 Mg ha^(-1) year^(-1)(LEsL).The amended plots received two doses of each amendment(DO2):one in October 2002 and another in October *** plots were then divided in half into two subpolts and one subplot received another two doses of the same amendments(DO4) in October 2005 and October *** 2011,the pH values of the amended soils were greater than that of the NA soil,with the sL-amended soil showing the highest *** organic carbon(TOC) was also greater in the amended soil,and greater with DO4 than with *** reduced the concentrations of 0.01 mol L^(-1) CaCl_2-extractable Cd,Cu and Zn,especially in the sL-amended *** cover of colonizing vegetation was enhanced by amendments,but was independent of amendment *** in soil properties from 2003 to 2011 showed that the first amendment application of DO2 caused a high differentiation between all the amendment treatments and the NA *** the second application of DO2,soil pH and TOC continued increasing *** two applications of amendments(DO4) caused differences only in the organic *** cover increased over time in all the treatments including *** could be concluded that the slow and steady natural remediation of this soil could be enhanced by amendment application(ANR).

关键词： amendment application CaCl2 extraction colonizing vegetation plant cover soil contamination soil property

A Note on Extreme Points in Dual spaces

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Acta Mathematica sinica,English series 2013年第3期29卷 471-476页

作者： Juan francisco MENA-JURADO Juan Carlos NAVARRO-PAsCUAL Departamento de Análisis Matemático Facultad de Ciencias Universidad de Granada Departamento de lgebra y Análisis Matemático Universidad de Almería

Given a normed space X it can be easily proven that every extreme point in Bx＊, the unit ball of X＊, is the restriction of an extreme point in Bx Our purpose is to study when the restrictions of extreme points in B... 详细信息

关键词： Extreme point Ll-predual M-ideal

structure–activity relationship in Ti phosphate-derived photocatalysts for H2 evolution

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Journal of Energy Chemistry 2017年第2期26卷 295-301页

作者： Diego Mateo francisco Gonell Josep Albero Avelino Corma Hermenegildo García Instituto de Tecnología Química Universitat Politècnica de València-Consejo superior de Investigaciones CientíficasAvenido de los Naranjos s/n46022 ValenciaSpain

Photocatalytic Hproduction has emerged as one of the most clean and promising renewable energy sources. In spite of the efforts to obtain efficient photocatalysts able to produce Hfrom sun light and water, there is still the need to prepare cheaper and environmental friendlier photocatalysts. Phosphatebased materials could be good candidates to fulfill these requirements. In this manuscript we have prepared a set of mixed Ti/Tivalence, open-framework titanium phosphates（of-TiPO） and mixed titanium oxide/phosphate derivatives（cr-Ti P）, correlating their structure and composition with the photocatalytic activity for Hproduction. We determined that mixed titanium oxide/phosphate crystalline phases produced enhanced Hevolution under sun simulated light irradiation than mixed Ti/Tivalence, open-framework titanium phosphates and titanium oxide phases.

关键词： Photocatalysis Hydrogen generation semiconductor

Highly graphitized carbon nanosheets with embedded Ni nanocrystals as anode for Li-ion batteries

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Nano Research 2020年第1期13卷 86-94页

作者： francisco Javier soler-Piña Celia Hernández-Rentero Alvaro Caballero Julián Morales Enrique Rodríguez-Castellón Jesús Canales-Vázquez Dpto.Química Inorgánica e Ingeniería Química Instituto de Química Fina y NanoquímicaUniversidad de Córdoba14071CórdobaSpain Dpto.Química Inorgánica Cristalografía y MineralogíaFacultad de CienciasUniversidad de Málaga29071MálagaSpain Instituto de Energías Renovables Universidad de Castilla-La ManchaPaseo de La Investigación 102071AlbaceteSpain

A C/Ni composite was prepared via thermal decomposition of a nickel oleate complex at 700℃,yielding disperse Ni nanocrystals with an average size of 20 nm,encapsulated by carbon nanosheets as deduced from transmission electron microscopy(TEM)images and confirmed from X-ray photoelectron spectroscopy(XPs).Furthermore,the X-ray diffraction pattern revealed a good ordering of the carbon layers,forced by the Ni encapsulation to adopt a bending *** the close interaction between the graphitized framework and the metallic nanoparticles we have studied the properties of the composite as an anode for Li-ion *** with other nanostructured synthetic carbons,this carbon composite has a low voltage hysteresis and a modest irreversible capacity value,properties that play a significant role in its behaviour as electrodes in full cell *** moderate rate values,0.25 C,the electrode delivers an average capacity value around 723 mAh·g^−1 on cycling,among the highest values so far reported for this carbon *** higher rate values,1 C,the average capacity values delivered by the cell on cycling decrease,around 205 mAh·g^−1,but it maintains good capacity retention,a coulombic efficiency close to 100%after the first cycles and recovery of the capacity values when the rate is restored from 3 to 0.1 C.

关键词： carbon nanosheets nickel nanoparticles anode lithium batteries

Low-cost experimental application of real-time kinematic positioning for increasing the benefits in cereal crops

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International Journal of Agricultural and Biological Engineering 2021年第3期14卷 194-199页

作者： Abdelhamid Tayebi Josefa Gómez Marián Fernández francisco sáez de Adana Oscar Gutiérrez Computer science Department University of AlcaláAlcaláde Henares 28801Spain

Traditional agriculture is facing several challenges worldwide such as increased population growth,rapid forestry and urbanization,resource scarcity,climate change,environmental pollution,competition among different ***,farmers need to improve productivity in order to maintain the output *** study attempted to evaluate the benefits of using Real-Time Kinematic(RTK)positioning in precision agriculture through a series of real measurements carried out when farming *** farming management actions involved in the cereal crop process(raise fallow,plow,sow,fertilize,mow,and harvest)have been done using an automatic guidance system that has reduced costs.A reduction of 20%has been quantified in the fuel,the amount of fertilizer,the labor costs and the hours of ***,the environmental impact has been also *** inexpensive system consisting of a reference base station near the field and a mobile unit mounted on the test vehicle has been installed in order to increase the benefits in cereal *** Navigation satellite system(GNss)systems including Global Positioning system(GPs),GLONAss,Galileo and Beidou have been used in the *** research serves as a practical guide to implementing a low-cost guidance system to achieve best management practice.

关键词： real-time kinematic low-cost positioning benefits guidance system cereal

An overview of end-of-life issues in a cardiology department. Is the mode of death worse in the cardiac intensive care unit?

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Journal of Geriatric Cardiology 2019年第6期16卷 482-489页

作者： Lourdes Vicent Vanesa Bruna Carolina Devesa Jorge García-Carreno Iago sousa-Casasnovas Miriam Juárez francisco Fernández-Avilés Manuel Martínez-sellés servicio de Cardiología Hospital Universitario Gregorio Maranon CIBERCV Madrid Spain Universidad Complutense de Madrid Madrid Spain Universidad Europea de Madrid Madrid Spain

Introduction Cardiovascular (CV) diseases are the most common causes of death and causes frequent hospital admissions.[1] The increase in life expectancy and the appearance of new treatments,[2] is changing in the clinical profile of CV disease, with a rise in chronic processes and concomitant comorbidities.[ 3] These changes are probably reflected in the current profile of patients admitted to cardiology departments, and in their causes of mortality.

关键词： Cardiovascular death Mortality Withdraw of life-sustaining therapies

On the Thermodynamical Black Hole stability in the space-Time of a Global Monopole in f(R)-Gravity

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Journal of High Energy Physics, Gravitation and Cosmology 2019年第3期5卷 587-611页

作者： francisco Bento Lustosa Maria Emilia Xavier guimaraes Cristine Nunes Ferreira Joaquim Lopes Neto Jose Abdalla Helayel-Neto Departamento de Fsica Teorica Instituto de FsicaUniversidade do Estado do Rio de JaneiroRio de JaneiroBrazil Instituto de Fsica Universidade Federal FluminenseCampus da Praia VermelhaNiteroiBrazil Nucleo de Estudos em Fsica Instituto Federal de Educacao Ciencia e Tecnologia FluminenseRio de JaneiroBrazil Instituto de Fsica Universidade Federal do Rio de JaneiroRio de JaneiroBrazil Centro Brasileiro de Pesquisas Fsicas Rio de JaneiroBrazil

In this work, we re-assess a class of black hole solutions in a global monopole spacetime in the framework of an f(R)-gravity model. Our main line of investigation consists in considering a region close enough to the black hole, but such that the weak field approximation is still valid. The stability of the black hole is studied in terms of its thermodynamical properties, with the radial coordinate written as a power-law function with the status of the main factor underneath the stability of the model. We obtain the explicit expressions for the thermodynamical quantities of the black hole as functions of the event horizon, by considering both the Hawking and the local temperatures. The phase transitions that may occur in this system, including the Hawking-Page phase transition, are inspected with particular attention. We work out and contemplate a solution of special interest in which one of the parameters is related to the cosmological constant. Our main result sets out to establish a comparison between both the Hawking and the local formalisms for the black hole in the framework of the f(R)-gravity in the particular space-time adopted here.

关键词： Black Hole f(R)-Gravity Hawking Temperature Global Monopole Cosmological Constant