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Chinese physics B 2024年第2期33卷 108-114页

作者： U.s.Mahabaleshwar G.p.Vanitha L.M.pérez Emad H.Aly I.pop department of studies in Mathematics Davangere UniversityShivagangothriDavangereIndia departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt department of Mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

Calibration of the dEM sliding friction and rolling friction parameters of a cohesionless bulk material

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particuology 2024年第9期92卷 126-139页

作者： Jonatan Marín pérez Tugrul Comlekci Yevgen Gorash donald MacKenzie University of strathclyde 75 Montrose StreetG11XJGlasgowUnited Kingdom

The discrete element method(dEM)has become a valuable tool for understanding the mechanical behaviour of granular assemblies,however,the accuracy of the dEM simulations depends on several interaction parameters such as the sliding friction and rolling friction ***,these parameters are estimated using bulk calibration approach(BCA)where the draw down test has been suggested as an effective way to approach these *** test provides up to four bulk criteria,the angle of repose,shear angle,mass flow rate and the mass loss which are used to narrow down the possible ***,there is still more research needed around it to fully understand how this methodology *** experimental and numerical study was carried out using the draw down test to assess the influence of different mass flow rates and particle shapes on dEM parameters for a cohesionless bulk *** is concluded that use of multi-sphere particles and three aperture sizes in the draw down test to calibrate the sliding and rolling friction parameters of a cohesionless bulk material can converge to a small feasible region in which a single combination of the friction coefficients can be *** calibrated sliding and rolling friction coefficients were validated using multi-sphere particles,where the maximum deviation was 5.9%from the experimental values.

关键词： discrete element method Calibration draw down sliding friction Rolling friction particle shape

Chromomagnetic dipole moments of light quarks in the bestest little Higgs model

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Chinese physics C 2024年第10期48卷 125-136页

作者： T.Cisneros-pérez E.Cruz-Albaro A.Y.Ojeda-Castañeda s.E.solís-Núñez Unidad Académica de Ciencias Químicas Universidad Autónoma de ZacatecasApartado Postal C-58598060 ZacatecasMexico Facultad de Física Universidad Autónoma de ZacatecasApartado Postal C-58098060 ZacatecasMexico

In this study,we investigated the anomalous Chromomagnetic dipole Moment(CMdM),denoted as μ_(q)^(BLHM),of light quarks q=(u,c,d,s,b) within the framework of the Bestest Little Higgs Model(BLHM)as an extension of the standard Model(sM).Our investigation encompassed novel interactions among the light quarks,heavy quark B,and heavy bosons (W'^(±),H^(±),φ^(±),η^(±))incorporating the extended Cabibbo-Kobayashi-Maskawa(CKM)matrix characteristic of the *** thoroughly explored the permissible parameter space,yielding a spectrum of CMdM values ranging from 10^(-10) to 10^(-3).

关键词： beyond standard model flavor physics chromomagnetic dipole light quarks

On-Chip Micro Temperature Controllers Based on Freestanding Thermoelectric Nano Films for Low-power Electronics

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Nano-Micro Letters 2024年第7期16卷 98-108页

作者： Qun Jin Tianxiao Guo nicolas perez Nianjun Yang Xin Jiang Kornelius Nielsch Heiko Reith Institute for Metallic Materials Leibniz Institute for Solid State and Materials Research01069 DresdenGermany Institute of Materials Engineering University of Siegen57076 SiegenGermany Institute of Applied physics Technical University of Dresden01069 DresdenGermany Institute of Materials science Technical University of Dresden01069 DresdenGermany

Multidimensional integration and multifunctional com-ponent assembly have been greatly explored in recent years to extend Moore’s Law of modern ***,this inevitably exac-erbates the inhomogeneity of temperature distribution in microsystems,making precise temperature control for electronic components extremely ***,we report an on-chip micro temperature controller including a pair of thermoelectric legs with a total area of 50×50μm^(2),which are fabricated from dense and flat freestanding Bi2Te3-based ther-moelectric nano films deposited on a newly developed nano graphene oxide membrane *** tunable equivalent thermal resistance is controlled by electrical currents to achieve energy-efficient temperature control for low-power electronics.A large cooling temperature difference of 44.5 K at 380 K is achieved with a power consumption of only 445μW,resulting in an ultrahigh temperature control capability over 100 K mW^(-1).Moreover,an ultra-fast cooling rate exceeding 2000 K s^(-1) and excellent reliability of up to 1 million cycles are *** proposed on-chip temperature controller is expected to enable further miniaturization and multifunctional integration on a single chip for microelectronics.

关键词： Temperature control Low-power electronics On-chip micro temperature controller Freestanding thermoelectric nano films Temperature-sensitive components

single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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Journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： s.pérez-Rodríguez M.Gutiérrez-Roa C.Giménez-Rubio d.Ríos-Ruiz p.Arévalo-Cid M.V.Martínez-Huerta A.Zitolo M.J.Lázaro d.sebastián Instituto de Carboquímica(CsIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y petroleoquímica(CsIC) Marie Curie 228049 MadridSpain synchrotron sOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRdE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRdE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

Assessment of energy consumption,environmental effects and fuel costs of the bus rapid transit system in Bogotá(Colombia)

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Clean Energy 2024年第3期8卷 34-47页

作者： Jhon Jairo pérez Luis Hernando Correa poul AlbergØstergaard pedro Cabrera Universidad de La salle-Engineering Faculty Electrical DepartmentCampus La CandelariaBogota D.C.Colombia Aalborg University Department of PlanningRendsburggade 149000 AalborgDenmark University of Las palmas de Gran Canaria Department of Mechanical EngineeringCampus Universitario de TafiraLas Palmas de Gran CanariaSpain

Colombia aims to boost the utilization of mass transportation systems in its major cities while simultaneously reducing greenhouse gas emissions by 20%,in alignment with the commitments of the COp21 *** 2020,the transport sector in Colombia accounted for 34.4%of the country’s energy demand and was responsible for~49%of its total CO_(2) *** article presents an assessment of energy consumption,environmental effects and the fuel costs of Bogotá’s bus rapid transit system based on the Activity,share,Intensity,Fuel methodology.A long-term analysis spanning from 2021 to 2040 was developed using the long-range energy alternatives planning *** conduct this assessment,the tool was calibrated using data from 2019 and *** distinct scenarios based on energy policies implemented in Bogotáwere examined:Business as Usual,Fast Transition,High Growth and Low *** energy consumption and environmental effects,the results underscore the pivotal role of diversifying energy sources and reducing reliance on fossil fuels such as ***,the analysis emphasizes the urgent need to accelerate the transition to alternative energy sources such as natural gas and electricity.

关键词： AsIF energy consumption environmental effects LEAp long-term energy model public transport

protein glycation:a wolf in sweet sheep’s clothing behind neurodegeneration

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Neural Regeneration Research 2024年第5期19卷 975-976页

作者： Ana B.Uceda Francisco Leal-pérez Miquel Adrover Institut Universitari d’Investigacióen Ciències de la salut(IUNICs) Institut d’Investigaciósanitària Illes Balears(IdIsBa) departament de Química Universitat de les Illes BalearsCtraPalma de MallorcaSpain

At the beginning of the 16th century,paracelsus coined the maxim:“the dose makes the poison”.This principle can be applied to all living organisms,including organs and *** brain and its glial and neuronal cells are ... 详细信息

关键词： organs sheep sweet

BaTiO3 solid solutions co-doped with Gd3+ and Eu3+:synthesis,structural evolution and dielectric properties

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Journal of Rare Earths 2024年第10期42卷 1920-1926页

作者： R.Martínez-López M.pérez-Labra J.A.Romero-serrano F.R.Barrientos-Hernández M.Reyes-pérez M.I.Valenzuela-Carrillo G.Urbano-Reyes V.E.Reyes-Cruz G.I.dávila-pulido Academic Area of Earth sciences and Materials Autonomous University of Hidalgo State Metallurgy and Materials department ESIQIE-IPNUPALM Autonomous University of Coahuila Boulevard Adolfo López Mateos S/n

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO3solid solutions codoped with rare earth elements(Gd3+and Eu3+) prepared using the solid-state reaction method are *** pure precursor powders of BaCl3,TiO2,Gd2O3,and Eu2O3were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 Mpa and sintered at 1300℃ in air atmosphere for 6 h to obtain Ba1-3xGd2xTi1-3xEu4xO3（x=0,0.0015,0.01 and0.1）.X-ray diffraction（XRd） and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO3for the samples with x=0,0.0015 and 0.01, as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd3+and Eu3+in the BaTiO3structure is reached for the sample with x>0.01,and the orthorhombic Eu2TiO5and monoclinic BaTi2O5secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO3around 716 cm-1（LO of A1 symmetry）,515 cm-1（TO of A1 symmetry）,and 305 cm-1（B1）.The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃ with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the *** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO3 doping Europium Gadolinium Rare earths synthesis

snapshot survey of the presence of perfluoroalkyl substances in products, Articles, and the Environment in Ecuador

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Engineering 2024年第6期37卷 49-61页

作者： Heidelore Fiedler Luis Vega-Bustillos Jenny Arias-pastrano Lander Vinicio pérez-Aldás Jose Castro-díaz MTM Research Centre School of Science and TechnologyÖrebro UniversityÖrebro 70182Sweden Undersecretariat of Environmental Quality Ministry of EnvironmentWater and Ecological Transition of EcuadorQuito 170525Ecuador department of Environmental Chemistry The Technical University of AmbatoHuachi CampusAmbato 180207Ecuador Alternativavision Ambiental Cia.Ltda. Mexico 03100Mexico

The stockholm Convention on persistent Organic pollutants(pOps)is a legally binding instrument for 186 parties(status:April 2023).Accordingly,among other responsibilities,countries are obliged to report the production,import,or export of the pOps listed in Annexes A,B,or C;provide information to registers;maintain inventories;and monitor the presence of pOps in the *** the broader context of international chemicals and waste management,producer responsibilities,harmonized reporting,and compliance with national and international regulations,Ecuador has addressed the newly listed group of perfluorinated alkyl substances(pFAs)in its national implementation plan and sent selected products from its national market for pFAs *** products analyzed came from the initially listed fields of specific exemptions and acceptable purposes,including:fire-fighting foams;photographic aids;greasers/degreasers;various kinds of paper/packaging;textiles;and leather,coatings,cleaners,metal plating,and *** results showed that the three pFAs presently listed in the stockholm Convention could be quantified in only a few samples;additional pFAs,not yet listed in the Convention also had low detection *** the number of samples was limited,the samples covered a large spectrum of sample matrices,making it possible to conclude that—once these products become waste and are regulated under the Basel Convention—they would not constitute a disposal ***,verification of the presence of pFAs in products on the market is expected to pose an analytical challenge for both,developed and developing countries.

关键词： Emerging or newly listed pOps stockholm Convention products and articles pFAs analysis developing countries

New therapeutic strategy with extracorporeal membrane oxygenation for refractory hepatopulmonary syndrome after liver transplant: A case report

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World Journal of Transplantation 2024年第1期14卷 210-214页

作者： Belinda sánchez pérez María pérez Reyes Jose Aranda Narvaez Julio santoyo Villalba Jose Antonio perez daga Claudia sanchez-Gonzalez Julio santoyo-santoyo Hepatobiliary and Trasplantation Unit General and Digestive Surgery DepartmentUniversity Regional HospitalMalaga 29010Spain department of General and digestive surgery Regional University Hospital of MalagaMalaga 29010Spain

BACKGROUNd due to the lack of published literature about treatment of refractory hepatopulmonary syndrome(Hps)after liver transplant(LT),this case adds information and experience on this issue along with a treatment with positive *** is a complication of end-stage liver disease,with a 10%-30%incidence in cirrhotic *** can reverse the physiopathology of this process and restore normal ***,in some cases,refractory hypoxemia persists,and extracorporeal membrane oxygenation(ECMO)can be used as a rescue therapy with good *** sUMMARY A 59-year-old patient with alcohol-related liver cirrhosis and portal hypertension was included in the LT waiting list for *** had good liver function(Model for End-stage Liver disease score 12,Child-pugh class B7).He had pulmonary fibrosis and a mild restrictive respiratory pattern with a basal oxygen saturation of 82%.The macroaggregated albumin test result was>*** demonstrated a forced expiratory volume in one second(FEV1)of 78%,forced vital capacity(FVC)of 74%,FEV1/FVC ratio of 81%,diffusion capacity for carbon monoxide of 42%,and carbon monoxide transfer coefficient of 57%.He required domiciliary oxygen at 2 L/min(16 h/d).The patient was admitted to the intensive care unit(ICU)and extubated in the first 24 h,needing high-flow therapy and non-invasive ventilation and inhaled nitric oxide *** was needed after 72 *** to the non-response to supportive therapies,installation of ECMO was decided with progressive recovery after 9 *** was possible on the tenth day,maintaining a high-flow nasal cannula and de-escalating to conventional oxygen therapy after 48 *** was discharged from ICU on postoperative day(pOd)20 with a 90%-92%oxygen *** recycling was needed twice for acute *** patient was discharged from hospital on pOd 27 with no symptoms,with an 89%-90%oxygen *** due to the favorable results observed,ECMO could bec

关键词： Liver transplantation Hepatopulmonary syndrome Refractory hypoxemia Treatment Extracorporeal membrane oxygenation Case report