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Mixed iridium-nickel oxides supported on antimony-doped tin oxide as h.gh.y efficient and stable acidic oxygen evolution catalysts

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Materials Futures 2024年第1期3卷 165-180页

作者： Jonath.n Ruiz Esquius Alec P LaGrow h.iyan Jin Zh.peng Yu Ana Araujo Rita Marques adélio Mendes Lifeng Liu Clean Energy Cluster International Iberian Nanotechnology LaboratoryAv.Mestre JoséVeigaBraga 4715-330Portugal Carbon Science and Tech.ology Institute INCAR-CSICFrancisco Pintado Fe 26Oviedo 33011Spain Scientific Imaging Section Okinawa Institute of Science and Technology Graduate UniversityKunigami-gunOkinawa 904-0412Japan Songsh.n Lake Materials Laboratory Dongguan 523808People’s Republic of China Laboratory for Process Engineering EnvironmentBiotechnology and EnergyFaculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal Associate Laboratory in Ch.mical Engineering Faculty of EngineeringUniversity of PortoRua Dr Roberto FriasPorto 4200-465Portugal.

Proton exch.nge membrane(PEM)water electrolysis represents a promising tech.ology for green h.drogen production,but its widespread deployment is greatly h.ndered by th. indispensable usage of platinum group metal catalysts,especially iridium(Ir)based materials for th. energy-demanding oxygen evolution reaction(OER).h.rein,we report a new sequential precipitation approach.to th. synth.sis of mixed Ir-nickel(Ni)oxy-h.droxide supported on antimony-doped tin oxide(ATO)nanoparticles(IrNiyO_(x)/ATO,20 wt.%(Ir+Ni),y=0,1,2,and 3),aiming to reduce th. utilisation of scarce and precious Ir wh.le maintaining its good acidic OER *** tested in strongly acidic electrolyte(0.1 M h.lO_(4)),th. optimised IrNi1Ox/ATO sh.ws a mass activity of 1.0 mAµgIr^(−1) and a large turnover frequency of 123 s^(−1) at an overpotential of 350 mV,as well as a comparatively small Tafel slope of 50 mV dec^(−1),better th.n th. IrOx/ATO control,particularly with.a markedly reduced Ir loading of only 19.7µgIr cm^(−2).Importantly,IrNi1O_(x)/ATO also exh.bits substantially better catalytic stability th.n oth.r reference catalysts,able to continuously catalyse acidic OER at 10 mA cm^(−2) for 15 h.with.ut obvious *** in-situ synch.otron-based x-ray absorption spectroscopy confirmed th.t th. Ir^(3+)/Ir^(4+)species are th. active sites for th. acidic ***,th. performance of IrNi1Ox/ATO was also preliminarily evaluated in a membrane electrode assembly,wh.ch.sh.ws better activity and stability th.n oth.r reference *** IrNi1Ox/ATO reported in th.s work is a promising alternative to commercial IrO_(2) based catalysts for PEM electrolysis.

关键词： mixed oxides oxygen evolution reaction polymer electrolyte membrane antimony doped tin oxide membrane electrode assembly

Cosmological Gravitational Redsh.ft, Spectral Sh.ft and Time in th. Taub-NUT Universe

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Journal of Modern Ph.sics 2024年第9期15卷 1448-1459页

作者： Ch.rles h. McGruder III Department of Ph.sics and Astronomy Western Kentucky University Bowling Green Kentucky USA

We demonstrate th.t: 1) Th. Taub-NUT universe is finite. 2) Th. Taub-NUT universe is much.larger th.n th. maximum observable distance according to th. standard th.ory of cosmology. 3) At large distances th. spectral s... 详细信息

关键词： Cosmology General Relativity

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Th. Unified Field

Journal of Modern Ph.sics 2024年第7期15卷 1010-1035页

作者： Joseph.h. (Cass) Forrington Managing Editor Journal of Cosmology California USA

Th.s is a Unified Field description based on th. h.lograph.c Time Dilation Cosmology, TDC, model, wh.ch.is an eternal continuum evolving forward in th. forward direction of time, at th. speed of ligh., c, at an invariant 1 s/s rate of time. Th.s is th. Fundamental Direction of Evolution, FDE. Th.re is also an evolution down time dilation gradients, th. Gravitational Direction of Evolution, GDE. Th.se evolutions are gravity, wh.ch.is th. evolutionary force in time. Gravitational velocities are compensation for th. difference in th. rate of time, dRt, in a dilation field, and th. dRtis equal to th. compensatory velocity’s percentage of c, and is a measure of th. force in time inducing th. velocity. In applied force induced velocities, th. dRt is a measure of th. resistance in time to th. induced velocity, wh.ch.migh. be called “anti-gravity” or “negative gravity”. Th. two effects keep th. continuum uniformly evolving forward at c. It is demonstrated th.t gravity is already a part of th. electromagnetic field equations in way of th. dRt element contained in th. TDC velocity formula. Einstein’s energy formula is defined as a velocity formula and a modified version is used for ch.rged elementary particle solutions. A time dilation-based derivation of th. Lorentz force ties gravity directly to th. electromagnetic field proving th. unified field of gravity and th. EMF. It is noted h.w we could possibly create gravity drives. Th.s is followed by a discussion of black h.les, proving supermassive objects, like massive black h.le singularities, are impossible, and th.t black h.les are massless Magnetosph.ric Eternally Collapsing Objects (MECOs) th.t are vortices in spacetime. .

关键词： Unified Field Gravity Anti-Gravity Astroph.sics Einstein General Relativity Special Relativity Galactic Rotation Velocities Time Dilation Spacetime Space Time Spacetime Continuum Quantum Continuum MECO Black h.le Event h.rizon Timelike Spacelike Ligh.like

Time Dilation Cosmology 2

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Journal of Modern Ph.sics 2024年第4期15卷 448-461页

作者： Joseph.h. (Cass) Forrington Managing Editor Journal of Cosmology California USA

Th.s paper is a furth.r elaboration of th. auth.r’s Time Dilation Cosmology (TDC) h.lograph.c model th.t ties gravitation and celestial mech.nics and kinematics directly to time dilation, resolving all th. major conundrums in astroph.sics, and ties astroph.sics directly to quantum ph.sics. It begins with.a brief summary of th. TDC model and contains th. new derivation for th. time dilation version of th. formula for summing relativistic velocities, Einstein’s gravitational constant and th. time dilation versions for th. Lorentz factor and th. Euclidean norm of th. 3d velocity vector, th. two of wh.ch.can th.n be used in th. Four-velocity formula. It is demonstrated h.w orbital curvature is manifested as th. resultant of two time dilation-manifested velocities. It also explains wh. an interferometer cannot distinguish.free fall from zero gravity and furth.r elaborates on th. auth.r’s previous explanations of h.w spiral galaxies are formed, and contains math.matical proof th.t Black h.les are actually Magnetosph.ric Eternally Collapsing Objects (MECOs) th.t are massless spacetime vortices.

关键词： Gravitation Time Time Dilation Celestial Mech.nics ISM: Kinematics and Dynamics Cosmology: Th.ory Galaxies: Evolution

Cosmology with.ut th. Cosmological Principle and with.ut Violating th. Copernican Principle: Taub-NUT Universe

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Journal of Modern Ph.sics 2024年第8期15卷 1069-1096页

作者： Ch.rles h. McGruder III Department of Ph.sics and Astronomy Western Kentucky University Bowling Green Kentucky USA

We develop a th.ory of cosmology, wh.ch.is not based on th. cosmological principle. We ach.eve th.s with.ut violating th. Copernican principle. It is well known th.t th. gravitational redsh.ft associated with.th. Sch.arzsch.ld solution applied to th. distant supernova does not lead to th. observed redsift-distance relationsh.p. We sh.w, h.wever, th.t generalizations of th. Sch.arzsch.ld metric, th. Taub-NUT metrics, do indeed lead to th. observed redsh.ft-distance relationsh.p and to th. observed time dilation. Th.se universes are not expanding rath.r th. observed cosmological redsh.ft is due to th. gravitational redsh.ft associated with.th.se solutions. Time dilation in th.se stationary universes h.s th. same dependency on redsh.ft th.t generally h.s been seen as proof th.t space is expanding. Our th.ory resolves th. h.bble tension.

关键词： Cosmology General Relativity

Extinction of Ligh. in th. Galactic h.lo: First Observational Evidence of th. Interaction of Ligh. and Dark Matter

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Journal of Modern Ph.sics 2024年第8期15卷 1144-1198页

作者： Ch.rles h. McGruder III Department of Ph.sics and Astronomy Western Kentucky University Bowling Green USA

We study th. distribution of quasars on th. celestial sph.re according to ground-based SDSS and space-based WISE and Gaia observations. All distributions as a function of galactic latitude, b, exh.bit a decrease in quasar frequency well outside th. dust in and near th. galactic plane. We prove th.t th. observed decrease in quasar frequency at h.gh.galactic latitudes is not accompanied by reddening, meaning th.t it can not be caused by dust. Th. scattering of ligh. by th. circumgalactic gas is negligible because th. Th.mson scattering cross section is very small. We conclude th. observed scattering of ligh. must be caused by dark matter in th. galactic h.lo. We determine th. mass and ch.rge of dark matter particles. If th. dark matter particle is a fermion its mass, mDMand ch.rge eDM=δe, wh.re e is th. elementary ch.rge are: mDM=3.2×10−2eV and δ=3.856×10−5. If h.wever th. dark matter particle is spinless th.n: mDM=0.511eV and δ=2.132×10−4. Th.se values for th. ch.rge of a dark matter particle are orders of magnitude h.gh.r th.n th. upper limit of th. neutrino ch.rge according to laboratory experiments. Consequently, dark matter particles are not ch.rged neutrinos. Since dark matter particles are ch.rged, th.y must emit and absorb electromagnetic radiation. h.wever, PDM~δ2, or: PDM~1.487×10−9Pe, wh.re Peis th. power output of a single electron.

关键词： Milky Way Dark Matter h.lo (1049)

Th. Early Warning Signs of a Stroke: An Approach.Using Mach.ne Learning Predictions

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Journal of Computer and Communications 2024年第6期12卷 59-71页

作者： Esraa h. Augi Almabruk Sultan Department of Computer Science University of Benghazi Benghazi Libya

Early stroke prediction is vital to prevent damage. A stroke h.ppens wh.n th. blood flow to th. brain is disrupted by a clot or bleeding, resulting in brain death.or injury. h.wever, early diagnosis and treatment reduce long-term needs and lower h.alth.costs. We aim for th.s research.to be a mach.ne-learning meth.d for forecasting early warning signs of stroke. Th. meth.dology we employed feature selection tech.iques and multiple algorith.s. Utilizing th. XGboost Algorith., th. research.findings indicate th.t th.ir proposed model ach.eved an accuracy rate of 96.45%. Th.s research.sh.ws th.t mach.ne learning can effectively predict early warning signs of stroke, wh.ch.can h.lp reduce long-term treatment and reh.bilitation needs and lower h.alth.costs.

关键词： Mach.ne Learning Stroke k-Nearest Neigh.ors Decision Tree Random Forest GXboost

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied Math.matics and Mech.nics(English.Edition) 2024年第3期45卷 543-562页

作者： h.M.FEIZABad M.h.YAS Department of Mech.nical Engineering Razi UniversityKermanshah ***Iran

Natural fibers h.ve been extensively research.d as reinforcement materials in polymers on account of th.ir environmental and economic advantages in comparison with.synth.tic fibers in th. recent *** fibers are renowned for th.ir good mech.nical properties,abundance,and sh.rt cycle *** beams are one of th. fundamental structural components and are susceptible to mech.nical loads in engineering applications,th.s paper performs a study on th. free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on th. elastic *** different functionally graded(FG)layouts and a uniform one are th. considered distributions for unidirectional long bamboo fibers across th. *** elastic properties of th. composite are determined with.th. law of *** h.milton’s principle,th. governing equations of motion are *** generalized differential quadrature meth.d(GDQM)is th.n applied to th. equations to obtain th. *** ach.eved outcomes exh.bit th.t th. natural frequency and buckling load values vary as th. fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of th. beam ***,a comparative study is conducted between th. derived analysis outcomes for BFRC and h.mogenous polymer beams to examine th. effectiveness of bamboo fibers as reinforcement materials,demonstrating th. significant enh.ncements in both.vibration and buckling responses,with.th. exception of natural frequencies for cantilever beams on th. Pasternak foundation with.th. FG-◇fiber ***,th. obtained analysis results of BFRC beams are also compared with.th.se for carbon nanotube reinforced composite(CNTRC)beams found in th. literature,indicating th.t th. buckling loads and natural frequencies of BFRC beams are lower th.n th.se of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature meth.d(GDQM)

Comparative ch.mical sensor for detection of ch.omium(VI) in aqueous solution

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Optoelectronics Letters 2024年

作者： Sura h. AL-Rekabi A.A.Alwah.b Electrical Tech.ique Department， Al Suwayrah.Tech.ical Institute， Middle Tech.ical University Laser and Optoelectronics Department， University of Tech.ology-Iraq

A process for purifying aqueous solutions containing h.avy and toxic metals such.as ch.omium h.s been investigated. One of th. extremely h.rmful pollutants in rivers and seawater are th. h.avy metal ions due to th.ir direct impact on h.man， animals and plants are h.xavalent ch.omium Cr （VI）. Consequently， h.gh.y sensitive sensor to detect Ch.omium is essential. Surface Plasmon resonance （SPR） tech.ique h.s attracted h.ge research.interest in detecting h.avy metals specifically. In th.s study， th.ee types of prism-based SPR sensor; gold （Au）/silver （Ag）， Au/polyaniline （PANI） and Au/ titanium dioxide (TiO2) nanostructured films are investigated as potential sensing material to detect th. presence of Cr （VI） ions in water. Th. base Au layer with.th.ckness of 48.3 nm is deposited on a glass slide for all sensors. For Au/Ag， Au/PANI nanofibers and Au/ (TiO2) sensor films， th. Cr （VI） concentration is varied from 1 to 15 ppm with.sensitivity of 0.270 o ppm-1， 0.082o ppm-1and 0.039 o ppm-1 respectively. Based on th.se results， th. Au/ PANI nanofibers are th. most sensitive to ch.omium Cr （VI） among tested sensing materials.

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