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On stability behaviors of 5D M-theory black objects

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Communications in Theoretical Physics 2024年第5期76卷 94-101页

作者： Adil Belhaj Abderrahim Bouhouch departement de Physique Equipe des Sciences de la matiere et du rayonnementESMaR Faculte des SciencesUniversite Mohammed V de RabatRabatMorocco

Using N=2 supergravity formalism,we investigate certain behaviors of five-dimensional black objects from the compactification of M-theory on a Calabi-Yau *** manifold has been constructed as the intersection of two homogeneous polynomials of degrees(ω+2,1)and(2,1)in a product of two weighted projective spaces given by WP^(4)(ω,1,1,1,1)×P^(1).First,we determine the allowed electric charge regions of the BPS and non BPS black holes obtained by wrapping M2-branes on appropriate two cycles in such a proposed Calabi-Yau *** that,we calculate the entropy of these solutions which takes a maximal value corresponding to ω=1 defining the ordinary projective space P^(4).For generic values of ω,we show that the non BPS states are ***,we conduct a similar study of five-dimensional black *** the allowed magnetic charge regions of the BPS and non BPS black stringy solutions derived from M5-branes on dual divisors,we calculate the tension taking a minimal value for P^(4).By determining the recombination factor,we show that the non-BPS black string states are stable in the allowed regions in the magnetic charge space.

关键词： M-theory Calabi-Yau manifolds black holes black strings stability behaviors

Numerical study on waste polyethylene pyrolysis driven by self-sustaining smoldering

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Science China(Technological sciences) 2024年第2期67卷 627-638页

作者： PAN RuMing WU YiBo GUENE LOUGOU Bachirou SHUAI Yong deBENEST Gérald School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China institut de Mecanique des Fluides de Toulouse(IMFT)-Universite de Toulouse CNRS-INPT-UPSToulouse 31400France

Polyethylene is the type of waste plastic that accounts for the most significant proportion of municipal solid *** polyethylene can be valorized via pyrolysis and produce value-added oil,gas,and *** the other hand,self-sustaining smoldering is an emerging technical means to deal with sand/soil contaminated by organic *** high-temperature heat generated by smoldering can be used as a heat source for pyrolyzing waste ***,this study investigates numerically the pyrolysis of waste polyethylene driven by self-sustaining smoldering.A novel 4-step lumped kinetic model is proposed for simulating the pyrolysis of waste *** results indicate that the operating parameters can determine the pyrolysis product yields by regulating the pyrolysis temperature and the volatile residence *** that higher temperatures and longer residence times favor the generation of shorter-chain pyrolysis products because of the intensified volatiles’secondary *** can be concluded that a high interface-wall heat transfer coefficient(400 W m^(-2)K^(-1)),a low PE content(0.20),a high char concentration(2.4%),and a moderate air velocity(0.040 m s^(-1))are beneficial to oil *** some extent,this study may broaden the boundaries for the application of self-sustained smoldering-driven pyrolysis.

关键词： self-sustained smoldering waste polyethylene thermal decomposition oil production waste valorization

Numerical Simulation of Turbulent Diffusion Flames of a Biogas Enriched with Hydrogen

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Fluid Dynamics & materials Processing 2024年第1期20卷 79-96页

作者： Naima Krarraz Amina Sabeur Khadidja Safer Ahmed Ouadha Laboratoire des Science et Ingénierie Maritimes Facultéde Génie MécaniqueUniversitédes Sciences et de la Technologie d’Oran Mohamed BoudiafOranAlgérie Laboratoire des Carburants Gazeux et de l’Environnement Facultéde Génie MécaniqueUniversitédes Sciences et de la Laboratoire des Carburants Gazeux et de l’Environneme

Any biogas produced by the anaerobic fermentation of organic materials has the advantage of being an environmentally friendly ***,the relatively low calorific value of such gases makes their effective utilization in practical applications relatively *** present study considers the addition of hydrogen as a potential solution to mitigate this *** particular,the properties of turbulent diffusion jet flames and the related pollutant emissions are investigated numerically for different operating *** related numerical simulations are conducted by solving the RANS equations in the frame of the Reynolds Stress Model in combination with the flamelet *** effects are also taken into account and the combustion kinetics are described via the GRI-Mech 3.0 reaction *** considered hydrogen fuel enrichment spans the range from 0%to 50%in terms of *** varies between 1 and 10 *** results show that both hydrogen addition and pressure increase lead to an improvement in terms of mixing quality and have a significant effect on flame temperature and *** also reduce CO_(2) emissions but increase NOx *** NO is shown to be the predominant NO formation mechanism.

关键词： Biogas hydrogen diffusion flame turbulence NO formation route pressure

Strategies to achieve effective nitrogen activation

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Carbon Energy 2024年第5期6卷 137-163页

作者： Bin Chang Huabin Zhang Shuhui Sun Gaixia Zhang KAUST Catalysis Center(KCC) King Abdullah University of Science and Technology(KAUST)ThuwalKingdom of Saudi Arabia institut National de la Recherche Scientifique(INRS) CentreÉnergie Matériaux TélécommunicationsVarennesQuébecCanada department of Electrical Engineering École de Technologie Supérieure(ÉTS)MontréalQuébecCanada

Ammonia serves as a crucial chemical raw material and hydrogen energy *** electrocatalytic nitrogen reduction reaction(NRR),powered by renewable energy,has attracted tremendous interest during the past few *** some achievements have been revealed in aqueous NRR,significant challenges have also been *** activity and selectivity are fundamentally limited by nitrogen activation and competitive hydrogen *** review focuses on the hurdles of nitrogen activation and delves into complementary strategies,including materials design and system optimization(reactor,electrolyte,and mediator).Then,it introduces advanced interdisciplinary technologies that have recently emerged for nitrogen activation using high-energy physics such as plasma and *** a better understanding of the corresponding reaction mechanisms in the coming years,these technologies have the potential to be extended in further *** review provides further insight into the reaction mechanisms of selectivity and stability of different reaction *** then recommend a rigorous and detailed protocol for investigating NRR performance and also highlight several potential research directions in this exciting field,coupling with advanced interdisciplinary applications,in situ/operando characterizations,and theoretical calculations.

关键词： activation via mediators catalyst optimization electrochemical nitrogen fixation high-energy activation of nitrogen nitrogen

Associations between physical activity levels and ATPase inhibitory factor 1 concentrations in older adults

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Journal of Sport and Health Science 2024年第3期13卷 409-418页

作者： Jérémy Raffin Yves Rolland Annelise Genoux Guillaume Combes Mikael Croyal Bertrand Perret Sophie Guyonnet Bruno Vellas Laurent O.Martinez Philipe de Souto Barreto For the MAPT/DSA Group institut du Vieillissement Gérontopôle de ToulouseCentre Hospitalo-Universitaire de ToulouseToulouse 31000France Centre d'Epidémiologie et de Recherche en Santédes Populations UnitéMixte de Recherche 1295Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse-III-Paul-SabatierToulouse 31000France LimitAging Team Institut des Maladies Métaboliques et CardiovasculairesUnitéMixte de Recherche 1297Institut National de la Santéet de la Recherche MédicaleUniversitéToulouse III-Paul SabatierToulouse 31432France Service de Biochimie Pôle de biologieHôpital de PurpanCentre Hospitalo-Universitaire de ToulouseToulouse 31300France L'institut du Thorax Institut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France BioCore US16Structure Fédérative de Recherche BonamyInstitut National de la Santéet de la Recherche MédicaleCentre National de la Recherche ScientifiqueCentre Hospitalo-Universitaire de NantesNantes UniversitéNantes 44000France Plate-forme de spectrométrie de masse Centre de Recherche en Nutrition HumaineOuestNantes 44000France 不详

Background:Adenosine triphosphatase inhibitory factor 1(IF1)is a key protein involved in energy ***1 has been linked to various agerelated diseases,although its relationship with physical activity(PA)remains ***,the apolipoprotein A-I(apoA-I),a PA-modulated lipoprotein,could play a role in this relationship because it shares a binding site with IF1 on the cell-surface ATP *** examined here the associations between chronic PA and plasma IF1 concentrations among older adults,and we investigated whether apoA-I mediated these ***:In the present work,1096 healthy adults(63.8%females)aged 70 years and over who were involved in the Multidomain Alzheimer Prevention Trial study were ***1 plasma concentrations(square root of ng/mL)were measured at the 1-year visit of the Multidomain Alzheimer Prevention Trial,while PA levels(square root of metabolic equivalent task min/week)were assessed using questionnaires administered each year from baseline to the 3-year *** linear regressions were performed to investigate the associations between the first-year mean PA levels and IF1 *** analyses were conducted to examine whether apoA-I mediated these *** linear regressions were carried out to investigate whether the 1-year visit IF1 concentrations predicted subsequent changes in ***:Multiple linear regressions indicated that first-year mean PA levels were positively associated with IF1 concentrations(B=0.021;SE=0.010;p=0.043).Mediation analyses revealed that about 37.7%of this relationship was mediated by apoA-I(B_(ab)=0.008;SE=0.004;p=0.023).Longitudinal investigations demonstrated that higher concentrations of IF1 at the 1-year visit predicted a faster decline in PA levels over the subsequent 2 years(time×IF1:B=0.148;SE=0.066;p=0.025).Conclusion:This study demonstrates that regular PA is associated with plasma IF1 concentrations,and it suggests that apoA-I partly med

关键词： Aging Apolipoprotein Bioenergetics Exerkine Mitochondria

Fluorophosphates and fluorosulfates cathode materials: Progress towards high energy density sodium-ion battery

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Nano Research 2024年第3期17卷 1427-1440页

作者： Mohammed Hadouchi Jingrong Hou Toshinari Koketsu Abdelilah Lahmar Jiwei Ma Laboratoire de Chimie Appliquée des matériaux Centre des Sciences des MatériauxFaculty of ScienceMohammed V University in RabatAvenue Ibn BattoutaBP 1014RabatMorocco Shanghai Key Laboratory for R&D and Application of Metallic Functional materials Institute of New Energy for VehiclesSchool of Materials Science and EngineeringTongji UniversityShanghai 201804China Battery materials development Section Business Creation Sector R&D CenterMitsui Mining&Smelting Co.Ltd.362-0021 SaitamaJapan Laboratoiry of Condensed matter Physics University of Picardie Jules Verne33 Rue Saint-Leu 80039AmiensFrance

The rapid diffusion of renewable energy boosts the wide deployment of large-scale energy storage *** the low cost and high crustal abundance,sodium-ion battery(SIB)technology is expected to become a dominant technology in that area in the *** the practical application,novel cathode materials are urged to develop that show high energy density without sacrificing their cost and benignity to the *** the years of many studies,this still remains a huge challenge to battery *** this review,we discuss recent breakthroughs in SIB cathode materials with high energy density,namely fluorphosphates and *** design of materials,the crystal structure,the electrochemical performance,and the underlaying intercalation mechanism are systematically *** strategies and research directions are also provided to advance future high-energy,low-cost,and ecofriendly cathode materials for next generation SIB.

关键词： fluorophosphates fluorosulfates crystal structure intercalation mechanism high energy density sodium-ion battery

Dynamics of Low-Viscosity Liquids Interface in an Unevenly Rotating Vertical Layer

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Fluid Dynamics & materials Processing 2024年第4期20卷 693-703页

作者： Victor Kozlov Vladimir Saidakov Nikolai Kozlov Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia institut de Mécanique des Fluides de Toulouse Toulouse INPToulouse31400France

The behavior of two immiscible low-viscosity liquids differing in density and viscosity in a vertical flat layer undergoing modulated rotation is experimentally *** layer has a circular axisymmetric *** the absence of modulation of the rotation speed,the interphase boundary has the shape of a short axisymmetric cylinder.A new effect has been discovered,under the influence of rotation speed modulation,the interface takes on a new dynamic equilibrium state.A more viscous liquid covers the end boundaries of the layer in the form of thin films,which have the shape of round spots of almost constant radius;with increasing amplitude of the velocity modulation,the wetting boundary *** is found that upon reaching the critical amplitude of oscillations,the film of a viscous liquid loses stability,and the outer edge of the wetting spot collapses and takes on a feathery *** is shown that this threshold is caused by the development of the Kelvin-Helmholtz oscillatory instability of the *** spreading radius of a spot of light viscous liquid and its stability are studied depending on the rotation rate,amplitude,and frequency of rotation speed *** discovered averaged effects are determined by different oscillatory interaction of fluids with the end-walls of the cell,due to different *** effect of films forming can find application in technological processes to intensify mass transfer at interphase boundaries.

关键词： Rotation oscillations immiscible fluids contact line interface film dynamic equilibrium Nomenclature frot

Monolithic metal-based/porous carbon nanocomposites made from dissolved cellulose for use in electrochemical capacitor

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Green Carbon 2024年第1期2卷 109-117页

作者： Madhav P.Chavhan Arjeta Kryeziu Somenath Ganguly Julien Parmentier University of Ostrava Faculty of Science30.dubna 22Ostrava 70103Czech Republic Universitéde Strasbourg Universitéde Haute-AlsaceInstitut de Science des Matériaux de Mulhouse(IS2M)UMR 7361 CNRS-UHA15 rue Jean StarckyBP 248868057 Mulhouse CedexFrance Indian institute of Technology Kharagpur Department of Chemical EngineeringKharagpurIndia

Porous metal-based carbon nanocomposites,with a monolithic shape,were prepared by a one-pot synthesis from dissolved cellulose and metallic salts using a simple,cheap,and environmentally friendly *** potential performances as electrochemical capacitors were tested with three metal precursors(M=Cu,Mn,and Fe)with two loadings and in an asymmetric cell for the Fe-based carbon ***,here soluble metal precursors were not deposited on a hard cellulose template but mixed in a precooled concentrated NaOH solution where cellulose was previously dissolved,allowing for a good dispersion of the metallic *** a freezing step where concomitant cellulose regeneration and pore ice-templating phenomena took place,followed by a carbonization step,the mixture led to a porous carbon monolith embedding well-dispersed metal-based nanoparticles having a diameter below 20 nm and present as metallic,oxide,or carbide phase(s)according to the element *** materials were characterized by different physicochemical techniques and electrochemical *** performances as supercapacitors are discussed in light of the specific behaviour of the metal-based phase and its influence on the carbon matrix properties such as mesopore formation and carbon *** asymmetric energy storage cell assembled with a Fe-based carbon electrode against a carbon xerogel electrode derived from a phenolic resin shows specific energy and power of 18.3 Wh kg^(−1)at 5 mA cm^(−2)and 1.6 kW kg^(−1)at 25 mA cm^(−2),respectively.

关键词： Cellulose Metal-based carbon nanocomposite Nanoparticles Monolith Supercapacitor

Bound and Resonating Multiquark Configurations

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Chinese Physics Letters 2024年第8期41卷 8-12页

作者： Jean-Marc Richard institut de Physique des 2 Infinis de Lyon Université Claude Bernard(Lyon 1) CNRS-IN2P34 rue Enrico Fermi69622 VilleurbanneFrance

We review the predictions of quark models for multiquark configurations that are bound or resonant states,and compare different methods for estimating the properties of resonances.

关键词： quark Configuration resonant