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Bl.ck hole shadows in Einstein-Bel-Robinson gravity

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chinese Physics c 2024年第5期48卷 272-283页

作者： B.Hamil B.c.lütfüoğlu laboratoire de Physique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-Bel-Robinson (EBR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric bl.ck hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS bl.ck hole shadows in EBR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the bl.ck holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： bl.ck hole shadows Einstein-Bel-Robinson gravity plasma

Investigation of the effects of radial.clearance on the screw conveyor performances for different inclinations

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Particuology 2024年第9期92卷 72-80页

作者： Berna Bolat Birgül Aşçıoğlu Temiztaş Enes Sezer Department of Mechanical Engineering Yıldız Technical University34349BeşiktaşİstanbulTurkey

Screw conveyors are widely used for bulk material *** study investigates the critical role of radial.clearance,the gap between the screw and the conveyor body,on performance across various inclination *** Discrete Element Method(DEM)is employed to analyze the effects of different radial.clearances on conveyor performance for concrete aggregate and sand as bulk *** efficiencies and capacity losses serve as key performance indicators,quantitatively assessed for each radial.clearance and inclination *** validation is conducted to corroborate the *** the study,the optimal radial.clearance was identified as 1.5 to 3 times of the particle *** optimal.clearance minimizes the material jamming and increases the performance for screw conveyors with different inclinations and bulk material types as a result.

关键词： Screw conveyors Radial.clearance Discrete element method(DEM) Volumetric efficiency conveyor performance

Adsorption of yttrium(Y^(3+)) and concentration of rare earth elements from phosphogypsum using chitin and chitin aerogel

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Journal of Rare Earths 2024年第4期42卷 775-782页

作者： Glaydson S.dos Reis Diana Pinto Sabrina F.lütke Eder c.lima luis F.o.Silva Irineu A.S.De Brum Guilherme l.Dotto Department of Forest Biomaterials and Technology Biomass Technology centre Swedish University of Agricultural SciencesUmeaE13Swedn Universidad De la costa Calle 58#55-66080002BarranquillaAtlanticoColombia Research Group on Adsorptive and catalytic Process Engineering(ENGEPAc) Federal University of Santa MariaAv.Roraima100079705900Santa MariaRSBrazil Institute of chemistry Federal University of Rio Grande do Sul90040060Porto AlegreBrazil

chitin powder and chitin-aerogel were prepared from shrimp wastes and used to uptake Y^(3+)from aqueous solutions and concentrate this rare earth element from phosphogypsum(PG).chitin aerogel displays a specific surface area of 945 m^(2)/g,while chitin powder is 3.6 m^(2)/g,which largely influences its adsorption *** the adsorption in synthetic solutions,the effect of pH on Y^(3+)removal is strong for chitin powder *** contrast,no big pH influence was detected for chitin *** interactions and chelation can highlight the proposed mechanism of Y^(3+)on chitin adsorbents for the powder and ***,in addition to these interactions,pore filling/pore diffusion is the main mechanism of Y^(3+)removal in the chitin *** aerogel is efficient in concentrating 8 times the Y^(3+)from PG,a very complex *** complex chitin aerogel-Y^(3+)can be a secondary source of rare earth elements for other appl.cations.

关键词： Rare earths Sustainable material chitin powder chitin porous aerogel Yttrium adsorption and recovery

Nonaqueous potassium-ion full.cells:Mapping the progress and identifying missing puzzle pieces

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Journal of Energy chemistry 2024年第6期93卷 384-399,I0010页

作者： Badre larhrib louiza larbi lénaïc Madec Universite de Pau et des Pays de l’Adour E2S UPPACNRSIPREMPauFrance Universitéde Haute-Alsace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance Réseau sur le Stockage El.ctrochimique de l’Energie CNRS FR3459AmiensFrance Institut des Matériaux Jean Rouxel(IMN) CNRS UMR 6502Univ.Nantes44322 Cedex 3 NantesFrance

This review addresses the growing interest for potassium-ion full.cells(KIFcs)in view of the transition from potassium-ion half-cells(KIHcs)toward commercial K-ion batteries(KIBs).It focuses on the key parameters of KIFcs such as the el.ctrode/el.ctrolyte interfaces challenge,major barriers,and recent advancements in *** strategies for enhancing KIFc performance,including interfaces co ntrol,el.ctrolyte optimization,el.ctrodes capacity ratio,el.ctrode material screening and el.ctrode design,are *** review highlights the need to evaluate KIBs in full.cell.configurations as half-cell results are strongly impacted by the K metal *** also emphasizes the importance of understanding solid el.ctrolyte interphase(SEI)formation in KIFcs and explores promising nonaqueous as well as quasiand all-solid-state el.ctrolytes *** review thus paves the way for practical.cost-effective,and scalable KIBs as energy storage systems by offering insights and guidance for future research.

关键词： K-ion full.cells Potassium-ion batteries cross-talk Solid-state batteries Potassium reactivity El.ctrolyte design El.ctrode design

optimization of bio-oil production parameters from the pyrolysis of elephant grass (Pennisetum purpureum) using response surface methodology

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clean Energy 2024年第5期8卷 241-251页

作者： Sunday c.Ikpeseni Samuel o.Sada Ufuoma J.Efetobor Henry o.orugba Mathias Ekpu Hilary I.owamah Jeremiah l.chukwuneke Solomon oyebisi Uche P.onochie Department of Mechanical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Delta State PolytechnicP.M.B.3Otefe-OgharaNigeria Department of chemical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of civil Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Nnamdi Azikiwe UniversityP.M.B.2025AwkaNigeria Department of civil Engineering Covenant UniversityP.M.B.1023OttaNigeria Department of civil Engineering The University of the South PacificP.M.B.9072SuvaFiji Department of Mechanical Engineering Delta State University of Science and TechnologyP.M.B.5OzoroNigeria

The need to increase bio-oil yield from biomass and enhance its fuel properties has driven research into optimizing the pyrolysis *** study investigated the influence of three key process parameters—temperature,heating rate,and nitrogen flow rate—on the pyrolysis of elephant grass(Pennisetum purpureum)in a fixed-bed *** surface methodology was used to study the im-pact of the aforementioned variables on bio-oil yield to improve its production *** analysis of the biomass revealed 79.24 wt%volatile matter,14.22 wt%fixed carbon,and 5.86%ash,with ultimate analysis showing 45.44%carbon,5.59%hydrogen,and 40.95%*** high volatile matter content and favourable carbon and hydrogen percentages indicate that elephant grass is a vi-able energy source due to its potential for high bio-oil yield and energy *** resulting bio-oil exhibited a higher heating value of 20.9 MJ/kg,indicating its suitability for various heating appl.cations.A second-order regression model was developed for bio-oil yield,with optimal.conditions identified as a temperature of 550°c,a heating rate of 17°c/min,and a nitrogen flow rate of 6 ml/*** study achieved an optimal bio-oil yield of 59.03 wt%,and the model’s high R²value of 0.8683 from analysis of variance analysis confirmed its predictive *** research highlights elephant grass as a sustainable feedstock for bio-oil production,offering valuable insights into optimizing pyrolysis conditions to enhance bio-oil yield,thus advancing biofuel technology.

关键词： renewable energy biomass sustainable feedstock regression model fixed-bed reactor

Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： leonardo Goliatt c.M.Saporetti l.c.oliveira E.Pereira Department of computational and Applied Mechanics Federal University of Juiz de ForaJuiz de ForaBrazil Department of computational Modeling Polytechnic InstituteRio de Janeiro State UniversityNova FriburgoBrazil Petrobras Rio de JaneiroBrazil Department of Stratigraphy and Paleontology Rio de Janeiro State UniversityRio de JaneiroBrazil

Rock samples'Toc content is the best indicator of the organic matter in source *** origin rock samples’analysis is used to calculate it manually by *** method requires time and resources because it relies on samples from many well intervals in source ***,research has been done to aid this *** learning algorithms can estimate total organic carbon instead of well logs and stratigraphic *** light of these efforts,the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and *** algorithms,differential evolution,particle swarm optimization,grey wolf optimization,artificial bee colony,and evolution strategies were used to improve machine learning models to predict *** six metaheuristics were integrated into four machine learning methods:extreme learning machine,elastic net linear model,linear support vector regression,and multivariate adaptive regression *** samples from the YuDong-Nan shale gas field,l.cated in the Sichuan basin,were used to evaluate the hybrid *** findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict *** results show that,independent of the metaheuristic used to guide the model sel.ction,optimized extreme learning machines attained the best performance scores according to six *** hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning Evolutionary algorithms Geology

A facile strategy for tuning the density of surface-grafted biomol.cules for melt extrusion-based additive manufacturing appl.cations

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Bio-Design and Manufacturing 2024年第3期7卷 277-291页

作者： I.A.o.Beeren G.Dos Santos P.J.Dijkstra c.Mota J.Bauer H.Ferreira Rui l.Reis N.Neves S.camarero-Espinosa M.B.Baker l.Moroni Department of complex Tissue Regeneration MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht University6229 ER MaastrichtThe Netherlands 3B’s Research Group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal IcVS/3B’s-PT Government Associate laboratory 4806-909 Braga/GuimarãesPortugal PolYMAT University of the Basque Country UPV/EHU20018 Donostia/San SebastiánSpain IKERBASQUE Basque Foundation for Science48009 BilbaoSpain

Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering ***,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control.cell *** of biomol.cules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface ***,we report a strategy to tune the surface density of bioactive groups by blending a low mol.cular weight poly(ε-caprol.ctone)5k(Pcl5k)containing orthogonally reactive azide groups with an unfunctionalized high mol.cular weight Pcl75k at different *** porous three-dimensional(3D)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low mol.cular weight Pcl *** a proof-of-concept test,we prepared films of three different mass ratios of low and high mol.cular weight polymers with a thermopress and reacted with an alkynated fluorescent model.compound on the surface,yielding a density of 201-561 pmol.cm^(2).Subsequently,a bone morphogenetic protein 2(BMP-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal.cells(hMScs)was *** two weeks of culturing in a basic medium,cells expressed higher levels of BMP receptor II(BMPRII)on films with the conjugated *** addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol.cm^(2)),indicating the importance of the surface *** together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material ***,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blending of(m

关键词： Additive manufacturing Blending Surface functionalization Surface density cl.ck chemistry Human

Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 197-216页

作者： c.G.PAVITHRA B.J.GIREESHA M.l.KEERTHI Department of PG Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3o_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3o_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal.characteristics of the trihybrid and hybrid nanofluids, excluding the thermal.conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTM) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fl.ctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTM) trihybrid nanofluid magnetic field

Blood metal.concentrations and cardiac structure and function in total joint arthroplasty patients

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World Journal of orthopedics 2024年第8期15卷 773-782页

作者： Peter c Brennan Stephanie M Peterson Thomas J o'Byrne Mariana l laporta cody c Wyles Paul J Jannetto Garvan c Kane Maria Vassilaki Hilal Maradit Kremers Department of orthopedic Surgery Mayo ClinicRochesterMN 55905United States Department of Quantitative Health Sciences Mayo ClinicRochesterMN 55905United States Department of Anesthesiology and Perioperative Medicine Mayo ClinicRochesterMN 55905United States Department of laboratory Medicine and Pathology Mayo ClinicRochesterMN 55905United States Department of cardiovascular Diseases Mayo ClinicRochesterMN 55905United States

BAcKGRoUND There is concern regarding potential long-term cardiotoxicity with systemic distribution of metals in total joint arthroplasty(TJA)*** To determine the association of commonly used implant metals with echocardiographic measures in TJA *** The study comprised 110 TJA patients who had a recent history of high chromium,cobalt or titanium *** underwent two-dimensional,three-dimensional,Doppler and speckle-strain transthoracic echocardiography and a blood draw to measure metal *** and sex-adjusted linear and logistic regression models were used to examine the association of metal.concentrations(exposure)with echocardiographic measures(outcome).RESUlTS Higher cobalt concentrations were associated with increased left ventricular end-diastol.c volume(estimate 5.09;95%cI:0.02-10.17)as well as left atrial and right ventricular dilation,particularly in men but no changes in cardiac *** titanium concentrations were associated with a reduction in left ventricle global longitudinal strain(estimate 0.38;95%cI:0.70 to 0.06)and cardiac index(estimate 0.08;95%cI,-0.15 to-0.01).coNclUSIoN Elevated cobalt and titanium concentrations may be associated with structural and functional.cardiac changes in some *** studies are warranted to better understand the systemic effects of metals in TJA patients.

关键词： Total joint arthroplasty Metal-on-metal cardiotoxicity Heart failure Echocardiography cobalt