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Numerical Simulation of Bed Load and Suspended Load Sediment Transport Using Well-Balanced Numerical Schemes

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Communications on Applied Mathematics and Computation 2023年第2期5卷 885-922页

作者： j.C.gonzález-Aguirre j.a.gonzález-Vázquez j.Alavez-Ramírez R.Silva M.E.Vázquez-Cendón División Acádemica de Ciencias Básicas Universidad Juárez Autónoma de TabascoCarr.Cunduacán-Jalpa de Mendéz KM.1CP 86690CunduacánTabascoMexico Universidad Autónoma Metropolitana-Unidad Iztapalapa Av.San Rafael Atlixco no.186Mexico CityMexico Instituto de Ingeniería Universidad Nacional Autónoma de México04510 Mexico CityMexico Departamento de Matemática Aplicada Universidade de Santiago de Compostela15706 Santiago de CompostelaSpain

Sediment transport can be modelled using hydrodynamic models based on shallow water equations coupled with the sediment concentration conservation equation and the bed con-servation *** complete system of equations is made up of the energy balance law and the Exner *** numerical solution for this complete system is done in a seg-regated ***,the hyperbolic part of the system of balance laws is solved using a finite volume *** ways to compute the numerical flux have been considered,the Q-scheme of van Leer,the HLLCS approximate Riemann solver,and the last one takes into account the presence of non-conservative products in the *** discretisation of the source terms is carried out according to the numerical flux *** the second stage,the bed conservation equation is solved by using the approximation computed for the system of balance *** numerical schemes have been validated making comparisons between the obtained numerical results and the experimental data for some physical *** numerical results show a good agreement with the experimental data.

关键词： Sediment transport Suspended load Bed load Finite volume method Numerical simulation Well-balanced schemes

Gas-phase electrocatalytic conversion of CO_2 to chemicals on sputtered Cu and Cu–C catalysts electrodes

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journal of Energy Chemistry 2019年第4期28卷 46-53页

作者： N.Gutiérrez-Guerra j.a.gonzález j.C.Serrano-Ruiz E.López-Fernández j.L.Valverde A.de Lucas-Consuegra Departamento de Ingeniería Química Facultad de Ciencias y Tecnologías Químicas Universidad de Castilla-La Mancha Instituto Regional de Investigación Científica Aplicada (IRICA) and Departamento de Física Aplicada Universidad de Castilla-La Mancha Departamento de Ingeniería Universidad Loyola Andalucía

A novel gas-phase electrocatalytic cell containing a low-temperature proton exchange membrane(PEM)was developed to electrochemically convert CO_2into organic *** different Cu-based cathode catalysts(Cu and Cu–C)were prepared by physical vapor deposition method(sputtering)and subsequently employed for the gas-phase electroreduction of CO_2at different temperatures(70–90°C).The prepared electrodes Cu and Cu–C were characterized by X-ray diffraction(XRD),X-ray photoemission spectroscopy(XPS)and scanning electron microscopy(SEM).As revealed,Cu is partially oxidized on the surface of the samples and the Cu and Cu–C cathodic catalysts were comprised of a porous,continuous,and homogeneous film with nanocrystalline Cu with a grain size of 16 and 8 nm,*** influence of the applied current and temperature on the electro-catalytic activity and selectivity of these materials was *** the two investigated electrodes,the pure Cu catalyst film showed the highest CO_2specific electrocatalytic reduction rates and higher selectivity to methanol formation compared to the Cu–C electrode,which was attributed to the higher particle size of the former and lower Cu O/Cu *** obtained results show potential interest for the possible use of electrical renewable energy for the transformation of CO_2into valuable products using low metal loading Cu based electrodes(0.5 mg Cu cm^(-2))prepared by sputtering.

关键词： CO_2 valorization Electro-reduction Cu catalyst PEM Selectivity Methanol production

Impact of Shaft Stiffness on Inertial Response of Fixed Speed Wind Turbines

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电力系统自动化 2012年第8期36卷 191-197页

作者： Francisco gonzlez-LONGATT Faculty of Engineering and Computing Coventry UniversityCoventry CV1 5FBUnited Kingdom

Future power system faces several challenges,one of them is the high penetration level of intermittent wind power generation,providing small or even no inertial response and being not contributing to the frequency *** effect of shaft stiffness on inertial response of fixed speed wind turbines is *** different drive-train models based on the multi-body system are *** small-signal analysis demonstrates no significant differences between models in terms of electro-mechanical eigen-values for increasing shaft *** natural resonance frequency of drive-train torsion modes shows slightly different values between damped and undamped models,but no significant differences are found in the number-mass ***-domain simulations show the changes in the active power contribution of a wind farm based on a fixed speed wind turbine during the system frequency *** changes in the kinetic energy during the dynamic process are calculated and their contribution to the inertia constant is small and *** largest contribution of the kinetic energy is provided at the beginning of the system frequency disturbance to reduce the rate of the frequency change,it is positive for the frequency stability.

关键词：风力发电机刚度模型惯性风力涡轮机频率稳定性轴定速传动系统

An explanation of the △_(D35)（1930） as a ρ△ bound state

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Chinese Physics C 2009年第12期33卷 1267-1272页

作者： P. gonzlez E. Oset j. Vijande Departamento de Física Teórica Universidad de Valencia (UV) e IFIC (UV - CSIC) Spain Departamento de Física Atómica Molecular y Nuclear Universidad de Valencia (UV) e IFIC (UV - CSIC) Spain

Constituent quark models based on two-body potentials systematically overpredict the mass of △D35(1930). A possible solution to this problem comes out from the application of a schematic hybrid model, containing three-quark as well as meson-baryon components, to the light-quark baryon spectrum. The △D35(1930) and its partners △D33(1940) and △S31(1900) are found to contain a significant ρ△ component. Then, through the use of the hidden gauge formalism, it is shown that these resonances can be dynamically generated from the ρ-△ interaction. In particular △D35(1930) can be interpreted as being essentially a ρ△bound state. This interpretation suggests that the inclusion of ρ△as an effective inelastic channel in data analyses could improve the extraction and identification of the resonance.

关键词： Particle physics and field theory

Hydrochar and synthetic natural gas co-production for a full circular economy implementation via hydrothermal carbonization and methanation:An economic approach

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journal of Environmental Sciences 2024年第6期140卷 69-78页

作者： judith gonzález-Arias Guillermo Torres-Sempere Miriam gonzález-Castaño Francisco MBaena-Moreno Tomás RReina Inorganic Chemistry Department and Materials Sciences Institute University of Seville-CSICSevilleSpain Materials Sciences Institute(ICMSE) CSIC-University of SevilleSevilleSpain Department of Chemistry and Chemical Engineering Chalmers University of TechnologyGothenburgSE 41296Sweden

Herein we study the economic performance of hydrochar and synthetic natural gas coproduction from olive tree *** process entails a combination of hydrothermal carbonization and *** a previous work,we evidenced that standalone hydrochar production via HTC results ***,we propose a step forward on the process design by implementing a methanation,adding value to the gas effluent in an attempt to boost the overall process techno-economic *** different plant capacities were analyzed(312.5,625 and 1250 kg/hr).The baseline scenarios showed that,under the current circumstances,our circular economy strategy in *** analysis of the revenues shows that hydrochar selling price have a high impact on NPV and subsidies for renewable coal production could help to boost the profitability of the *** the contrary,the analysis for natural gas prices reveals that prices 8 times higher than the current ones in Spain must be achieved to reach *** seems unlikely even under the presence of a strong subsidy *** costs analysis suggests that a remarkable electricity cost reduction or electricity consumption of the HTC stage could be a potential strategy to reach profitability ***,significant reduction of green hydrogen production costs is deemed instrumental to improve the economic performance of the *** results show the formidable techno-economic challenge that our society faces in the path towards circular economy societies.

关键词： Hydrothermal carbonization CO_(2)waste valorization Methanation Profitability analysis

Enhancement of the CO_(2)adsorption and hydrogenation to CH_(4)capacity of Ru–Na–Ca/γ–Al_(2)O_(3)dual function material by controlling the Ru calcination atmosphere

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journal of Environmental Sciences 2024年第6期140卷 292-305页

作者： Alejandro Bermejo-López Beñat Pereda-Ayo jon A.Onrubia-Calvo joséA.gonzález-Marcos juan R.gonzález-Velasco Department of Chemical Engineering Faculty of Science and TechnologyUniversidad del País Vasco UPV/EHUBarrio Sarrienas/n48940 LeioaBizkaiaSpain

Integrated CO_(2)capture and utilization(ICCU)technology requires dual functional materials(DFMs)to carry out the process in a single reaction *** influence of the calcination atmosphere on efficiency of 4%Ru-8%Na_(2)CO_(3)-8%CaO/γ-Al_(2)O_(3)DFM is *** adsorbent precursors are first co-impregnated onto alumina and calcined in ***,Ru precursor is impregnated and four aliquotes are subjected to different calcination protocols:static air in muffle or under different mixtures(10%H_(2)/N_(2),50%H_(2)/N_(2)and N_(2))*** are characterized by XRD,N_(2)adsorption-desorption,H_(2)chemisorption,TEM,XPS,H_(2)-TPD,H_(2)-TPR,CO_(2)-TPD and *** catalytic behavior is evaluated,in cycles of CO_(2)adsorption and hydrogenation to CH_(4),and temporal evolution of reactants and products concentrations is *** calcination atmosphere influences the physicochemical properties and,ultimately,activity of *** data and catalytic performance discover the acccomodation of Ru nanoparticles disposition and basic sites is mostly influencing the catalytic *** calcined under N_(2)flow(RuNaCa-N_(2))shows the highest CH_(4)production(449μmol/g at 370℃),because a well-controlled decomposition of precursors which favors the better accomodation of adsorbent and Ru phases,maximizing the specific surface area,the Ru-basic sites interface and the participation of different basic sites in the CO_(2)methanation ***,the calcination in a N_(2)flow is revealed as the optimal calcination protocol to achieve highly efficient DFM for integrated CO_(2)adsorption and hydrogenation applications.

关键词： CO_(2)methanation Integrated CO_(2)capture and utilization(ICCU) Dual functional material(DFM) Ru calcination atmosphere

Control-based Fault Current Limiter for Minimizing Impact of Distributed Generation Units on Protection Systems

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journal of Modern Power Systems and Clean Energy 2023年第2期11卷 643-650页

作者： Pablo E.Muñoz Ricardo j.Mantz Sergio A.gonzález Instituto LEICI UNLPCONICETLa Plata 1900La PlataArgentina Commission of Scientific Researches of the Buenos Aires Province(CICpBA) La PlataArgentina

Distributed generation units(DGUs)bring some problems to the existing protection system,such as those associated with protection blinding and sympathetic *** is known that fault current limiters(FCLs)help minimize the negative impact of DGUs on the protection *** this paper,a control-based FCL is proposed,i.e.,the FCL is integrated into the DGU control *** this end,a predictive control strategy with fault current limitation is *** this way,a DGU is controlled,not only for power exchange with the power grid but also to limit its fault current *** proposal is posed as a constrained optimization problem allowing taking into account the current limit explicitly in the design process as a closed-loop solution.A linear approximation is proposed to cope with the inherent nonlinear *** proposal does not require incorporating extra equipment or mechanisms in the control loop,making the design process *** evaluate the proposed control-based FCL,both protection blinding and sympathetic tripping scenarios are *** control confines the DGU currents within the constraints quickly,avoiding large transient ***,the impact on the protection system is reduced without the necessity that the DGU goes out of service.

关键词： Distributed generation distribution network protection power electronic converter fault current limiter model-based predictive controller

THE BANACH-LIE GROUP OF LIE TRIPLE AUTOMORPHISMS OF AN H^＊-ALGEBRA^＊

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Acta Mathematica Scientia 2010年第4期30卷 1219-1226页

作者： A.j.Calderón Martín C.Martín gonzález Departamento de Matemáticas Universidad de Cádiz Departamento de Algebra Geometría y Topología Universidad de Málaga

We study the Banach-Lie group Ltaut（A） of Lie triple automorphisms of a complex associative H^＊-algebra A. Some consequences about its Lie algebra, the algebra of Lie triple derivations of A, Ltder（A）, are obtained. For a topologically simple A, in the infinite-dimensional case we have Ltaut（A）0 = Aut（A） implying Ltder（A） = Der（A）. In the finite-dimensional case Ltaut（A）0 is a direct product of Aut（A） and a certain subgroup of Lie derivations δ from A to its center, annihilating commutators.

关键词： Banach-Lie group Lie triple automorphism Lie triple derivation

Evaluating physical changes of iron oxide nanoparticles due to surface modification with oleic acid

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Chinese Physics B 2020年第10期29卷 186-194页

作者： S Rosales N Casillas A Topete O Cervantes G gonzález j A Paz M E Cano Centro Universitario de Ciencias Exactas e Ingenienas Universidad de GuadalajaraBlvd.Marcelino Garcia Burragan 1421C.P.44430GuadalajaraJaliscoMexico Centro Universitario de la Cienegu Universidad de GuadalajaraAv.Universidad 1115C.P.47820OcotlanJaliscoMexico Centro Universitario de Ciencias de In Salud Universidad de Guadalajara.Sierra Mojada 950C.P.44340GuadalajaraJaliscoMexico

The physical characterization of a colloidal system of superficially modified magnetic nanoparticles (MNPs) is presented. The system consists of oleic acid-coated iron oxide nanoparticles (OAMNP) suspended in water. A structural analysis is carried out by using standard physical techniques to determine the diameter and shape of the MNPs and also the width of the coating shell. The colloidal stability and the polydispersity index of this ferrofluid are determined by using Zeta potential measurements. Additionally, the magnetic characterization is conducted by obtaining the DC magnetization loops, and the blocking temperatures are determined according to the ZFC–FC protocol. Finally, the values of power absorption density P of the ferrofluid are estimated by using a magneto-calorimetric procedure in a wide range of magnetic field amplitude H and frequency f. The experimental results exhibit spherical-like shape of OAMNP with (20 ± 4) nm in diameter. Due to the use of coating process, the parameters of the magnetization loops and the blocking temperatures are significantly modified. Hence, while the uncoated MNPs show a blocking state of the magnetization, the OAMNP are superparamagnetic above room temperature (300 K). Furthermore, the reached dependence P versus f and P versus H of the ferrofluid with coated MNPs are clearly fitted to linear and quadratic correlations, respectively, showing their accordance with the linear response theory.

关键词： nanoparticles ferrofluid magnetic hyperthermia functionalization