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Fuel cell stack design and modelling with a double-stage boost converter coupled to a single-phase inverter

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Clean Energy 2024年第1期8卷 188-196页

作者： Basem E.Elnagi Ahmed m.Ismaiel Hany s.E.mansour m.N.Abd-Alwahab Electrical Engineering Department Faculty of EngineeringSuez Canal UniversityIsmailia 41522Egypt

A comprehensive proton-exchange membrane fuel cell stack model was developed and integrated with a two-stage DC/DC boost *** was directly coupled to a single-phase(two levels-four pulses)inverter without a *** pulse-width modu-lation signal was used to independently regulate every converter *** converter was modelled using a mATLAB®/simulink®environment and an appropriate voltage control *** analysis features of the suggested circuit were created and,through established experiments,the simulation results were verified.A single-phase(two levels-four pulses)inverter control circuit was tested and it produced a pure sinusoidal waveform with voltage *** matches the voltage of the network in terms of amplitude and frequency.A sinusoidal pulse-width modulation approach was performed using a single-phase(two levels-four pulses)pulse-width modulation *** results demonstrated an enhancement in the standard of the output wave and tuned the dead time with a reduction of 63μs compared with 180μs in conventional techniques.

关键词： PEm fuel cell pulse-width modulation single-phase inverter and double-stage DC/DC boost converter

Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

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High Power Laser science and Engineering 2024年第3期12卷 62-68页

作者： L.R.Yin X.F.Li Y.J.Gu N.Cao Q.Kong m.Büscher s.m.Weng m.Chen Z.m.sheng Key Laboratory of Nuclear Physics and Ion-beam Application(moE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina state Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina sANKEN(Institute of scientific and Industrial Research) Osaka UniversityOsakaJapan sichuan Research Institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg Institut(PGI-6) Forschungszentrum JülichJülichGermany Institut für Laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany Key Laboratory for Laser Plasmas(moE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFsA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee Institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±Bargmann±michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

synthetic polymers:A review of applications in drilling fluids

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Petroleum science 2024年第1期21卷 475-518页

作者： shadfar Davoodi mohammed Al-shargabi David A.Wood Valeriy s.Rukavishnikov Konstantin m.minaev school of Earth sciences&Engineering Tomsk Polytechnic UniversityLenin AvenueTomskRussia DWA Energy Limited LincolnUnited Kingdom

With the growth of deep drilling and the complexity of the well profile,the requirements for a more complete and efficient exploitation of productive formations increase,which increases the risk of various ***,reagents based on modified natural polymers(which are naturally occurring compounds)and synthetic polymers(sPs)which are polymeric compounds created industrially,are widely used to prevent emerging complications in the drilling ***,compared to modified natural polymers,sPs form a family of high-molecular-weight compounds that are fully synthesized by undergoing chemical polymerization *** provide substantial flexibility in their ***,their size and chemical composition can be adjusted to provide properties for nearly all the functional objectives of drilling *** can be classified based on chemical ingredients,type of reaction,and their responses to ***,some of sPs,due to their structural characteristics,have a high cost,a poor temperature and salt resistance in drilling fluids,and degradation begins when the temperature reaches 130℃.These drawbacks prevent sP use in some medium and deep ***,this review addresses the historical development,the characteristics,manufacturing methods,classification,and the applications of sPs in drilling *** contributions of sPs as additives to drilling fluids to enhance rheology,filtrate generation,carrying of cuttings,fluid lubricity,and clay/shale stability are explained in *** mechanisms,impacts,and advances achieved when sPs are added to drilling fluids are also *** typical challenges encountered by sPs when deployed in drilling fluids and their advantages and drawbacks are also *** issues also impact the applications of sPs in drilling ***,the cost of the most relevant sPs,and the monomers used in their synthesis,are *** impacts of sPs when deployed in drilling fluids,and t

关键词： synthetic versus natural polymers Nanopolymers Drilling fluid additives Lubricity Clay swelling Hole cleaning

Common coupled fixed point theorem for two pairs compatible and sub-sequentially continuous mapping

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Journal of Ocean Engineering and science 2024年第4期9卷 401-407页

作者： H.m.Abu-Donia mona s.Bakry H.A.Atia Omnia m.A.Khater Raghda A.m.Attia Department of mathematics Faculty of ScienceZagazig UniversityZagazigEgypt Department of mathematics Faculty of ScienceTanta UniversityTantaEgypt Department of Basic science Zagazig Higher Institute of Engineering and TechnologyZagazigEgypt Department of Basic science Higher Technological Institute 10th of Ramadan CityEl Sharqia 44634Egypt

This study establishes a common coupled fixed point for two pairs of compatible and sequentially continuous mappings in the intuitionistic fuzzy metric space that satisfy theφ-contractive *** basic definitions and theorems have been used from some recent scientific papers about the binary operator,t-norm,t-conorm,intuitionistic fuzzy metric space,and compatible mapping for reaching to the paper’s purpose.

关键词： Intuitionistic fuzzy metric space φ-contractive mapping Compatible mappings Couple fixed point

C-phycocyanin shows neuroprotective effect against rotenone-induced Parkinson’s disease in mice

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Asian Pacific Journal of Tropical Biomedicine 2024年第7期14卷 279-287页

作者： Hritik Rathod Ritu m.soni Jigna s.shah Department of Pharmacology Institute of Pharmacy Nirma UniversityAhmedabadGujaratIndia

Objective:To investigate the neuroprotective effect of C-phycocyanin in a mouse model of rotenone-induced Parkinson’s ***:C-phycocyanin(50 mg/kg,i.p.,daily)was administered to rotenone(30 mg/kg,p.o.,daily)treated mice for 28 *** studies(Y-maze,rotarod,round beam walk,and wire-hang tests)were carried out to assess neurobehavioral *** and malondialdehyde were determined in both serum and striatal *** proteins(AKT,AmPK,NF-κB,BDNF,and alpha-synuclein)in the striatum were estimated using *** analyses(hematoxylin and eosin stainning as well as Nissl staining)were carried out to assess structural abnormalities in the ***:C-phycocyanin significantly increased BDNF levels and decreased alpha-synuclein *** also slightly upregulated AmPK and AKT levels without significant difference compared with the rotenone ***,rotenone-induced elevated oxidative stress and structural abnormalities in the striatum were markedly mitigated by ***:C-phycocyanin might have potential neuroprotective effects against Parkinson’s *** studies are warranted to verify its efficacy and to understand the molecular mechanisms behind the neuroprotective effects of C-phycocyanin in Parkinson’s disease.

关键词： Parkinson’s disease C-phycocyanin Alphasynuclein BDNF Oxidative stress Rotenone

A critical review towards the causes of the iron-based catalysts deactivation mechanisms in the selective oxidation of hydrogen sulfide to elemental sulfur from biogas

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Journal of Energy Chemistry 2024年第3期90卷 388-411,I0010页

作者： mostafa Tarek Janaina s.santos Victor márquez mohammad Fereidooni mohammad Yazdanpanah supareak Praserthdam Piyasan Praserthdam Center of Excellence on Catalysis and Catalytic Reaction Engineering(CECC) Department of Chemical EngineeringFaculty of EngineeringChulalongkorn UniversityBangkok 10330Thailan High-Performance Computing Unit(CECC-HCU) Center of Excellence on Catalysis and Catalytic Reaction Engineering(CECC)Chulalongkorn UniversityBangkok 10330Thailand

Hydrogen sulfide(H_(2)s) not only presents significant environmental concerns but also induces severe corrosion in industrial equipment,even at low *** various technologies,the selective oxidation of hydrogen sulfide(sOH_(2)s) to elemental sulfur(s) has emerged as a sustainable and environmentally friendly *** to its unique properties,iron oxide has been extensively investigated as a catalyst for sOH_(2)s;however,rapid deactivation has remained a significant *** causes of iron oxide-based catalysts deactivation mechanisms in sOH_(2)s,including sulfur or sulfate deposition,the transformation of iron species,sintering and excessive oxygen vacancy formation,and active site loss,are thoroughly examined in this *** focusing on the deactivation mechanisms,this review aims to provide valuable insights into enhancing the stability and efficiency of iron-based catalysts for sOH_(2)s.

关键词： selective oxidation of H_(2)s Iron-based Catalysts mechanism of deactivation sulfur or sulfate deposition Transformation of iron species sintering sDG 7

Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

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Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： m.Grandin H.K.Connor s.Hoilijoki m.Battarbee Y.Pfau-Kempf U.Ganse K.Papadakis m.Palmroth Department of Physics University of HelsinkiHelsinkiFinland NAsA Goddard space Flight Center GreenbeltMD20771USA space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing *** solar wind magnetosphere Ionosphere Link Explorer(smILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their soft X-ray Imager(sXI)*** earlier modeling works have already simulated soft X-ray images as might be obtained by smILE sXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space *** investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator *** simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic *** first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the *** results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the smILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray *** instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this ***,a proton density increase by 14%in the magnetosheath

关键词： magnetosphere magnetosheath numerical simulation smILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

Provenance and tectonic setting of sandstones of the Lomas Coloradas Formation, Cabullona Group, sonora, méxico: Constraints on petrography and geochemistry

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Journal of Palaeogeography 2024年第4期13卷 839-861页

作者： J.madhavaraju D.G.Noriega-montoya E.Ramirez-montoya C.m.Gonz alez-Le on John s.Armstrong-Altrin Estaci on Regional del Noroeste Instituto de GeologíaUniversidad Nacional Aut onoma de Mexico Ingeniería en Geociencias Universidad Estatal de Sonora Posgrado en Ciencias de la Tierra Estaci on Regional del NoroesteInstituto de GeologíaUniversidad Nacional Aut onoma de Mexico Universidad Nacional Aut onoma de mexico Instituto de Ciencias del Mar y LimnologíaUnidad de Procesos Oce anicos y CosterosCiudad Universitaria

The sedimentary rocks of the Cabullona Group are well exposed in the Cabullona Basin of northeastern sonora, mexico, which represent syntectonic sedimentation associated with Laramide-style deformation during the Campanian-early maastrichtian. The sandstones of the Lomas Coloradas Formation deposited at the upper part of the Cabullona Group. Petrography and geochemical(major, trace, and rare earth elements) studies were carried out on the sandstones to interpret the palaeoweathering, provenance,and tectonic setting of the Lomas Coloradas Formation sandstones. most of the sandstone modal analysis data plotted in the QFL and Qm FLt ternary diagrams fall into the fields of dissected arcs and recycled orogens,respectively. Geochemically the sandstones are classified as litharenites while few samples plot into the arkosic field. The chondrite-normalized REE diagrams for sandstones have LREE-enriched, relatively flat HREE patterns with negative Eu anomalies. CIA values and the A-CN-K diagram indicate a low intensity of chemical weathering in the source area. The tectonic setting diagram suggests both arc and rift settings for the studied sandstones. The bivariate and ternary diagrams and elemental ratios suggest a felsic source for the Lomas Coloradas Formation. The average REE patterns of the studied sandstones are comparable with REE patterns of the granite from the Caborca block, the rhyolite and granite of the Tarahumara Formation, and the mesozoic felsic volcanic rocks. The modeled mixture of 40% Proterozoic granite, 30% Triassic arc, 10% Jurassic arc, and 20% Laramide arc represents the probable source rocks for the Lomas Coloradas Formation.

关键词： Provenance Petrography Geochemistry Lomas Coloradas Formation Cabullona Group méxico

Rare earth-doped mixed Ni-Cu-Zn ferrites as an effective photocatalytic agent for active degradation of Rhodamine B dye

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Journal of Rare Earths 2024年第3期42卷 488-496,I0003页

作者： swapnil A.Jadhav sandeep B.somvanshi sudarshan s.Gawali Kranti Zakde K.m.Jadhav Department of Physics Dr.Babasaheb Ambedkar Marathwada UniversityAurangabad431004MaharashtraIndia school of materials Engineering Purdue UniversityWest Lafayette 47906USA University Department of Basic and Applied sciences MGM UniversityAurangabad431003MaharashtraIndia

In this study, a series of Gd^(3+)-doped mixed Ni-Cu-Zn ferrites with composition of Zn_(0.5)Ni_(0.3)Cu_(0.2)Fe_(2-x)Gd_(x)O_(4)(x = 0, 0.025, 0.05, 0.075, 0.1) was prepared using self-ignition sol-gel method. The prepared nanoparticles with an average size ranging from 22 to 26 nm show a single-phase cubic structure belonging to the spinel matrix. A rise in the Gd^(3+)concentration leads to an increase in crystallite size and lattice parameter. In Fourier transform infrared spectra, two main absorption bands belonging to the spinel structure are observed. The high-frequency bands(v_(1)) represent the tetrahedral complex, while the lowfrequency bands(v_(2)) signify the octahedral complex. The optical bandgap of the nanoferrites is found within the range of 2.91 to 2.41 eV, depending on their size. The magnetic characteristics of the material,such as saturation magnetization and coercivity are significantly altered with the concentration of Gd^(3+)in the solution. Using Rhodamine B(RhB) as a model organic pollutant, an in-depth investigation of the photocatalytic activity of the compounds was carried out. The present outcomes show that adding an adequate amount of Gd^(3+)significantly enhances the number of hydroxyl radicals produced by the ferrite,in turn, increasing the photocatalytic activity of the material. mechanism elucidated by scavenger studies reveals that ·OH and holes are the primary reactive radicals responsible for the degradation *** photocatalysts show an insignificant performance loss in five consecutive cycles. Thus, it is concluded that these photocatalysts are highly suitable for the remediation of dye-contaminated wastewater.

关键词： Gd^(3+)substitution spinel ferrite structural properties magnetic properties Photocatalysis Rare earths