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https://doi.wikipt.org/10.1490/77009901.10990tpl

5 Desember 2025 om 06:45:00

Development of a Next-Generation PEM Fuel Cell Incorporating Nanostructured Polymer Membranes, Pt-Co-ZrO₂ Electrocatalysts, and Dual-Region MEA Architecture

Polymer electrolyte membrane fuel cells offer efficient, low-temperature, fast-starting clean energy. Thin polymer membranes enable strong proton conduction and high power density with fewer emissions. Advances in catalysts, electrodes, and nanostructured polymers improve durability, cost, and scalability, positioning PEM fuel cells as key technologies for future sustainable power.

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9

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10

Theoretical Physics Letters
2025 ° 12(05) ° 0695-9887
https://www.wikipt.org/tphysicsletters
Intellectual article ID- PTL/7580562514

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9

nanotechnology, Fuel Cell, Pt-Co-ZrO₂ Electrocatalysts, TEM, Quantum System

Dirac Quasinormal Modes in Noncommutative Reissner-Nordström Black Holes

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https://doi.wikipt.org/10.1490/77009901.9887tpl

19 Oktober 2025 om 05:00:00

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Dirac Quasinormal Modes in Noncommutative Reissner-Nordström Black Holes

This study investigates Dirac quasinormal modes (QNMs) in a deformed Reissner-Nordström black hole spacetime influenced by noncommutative (NC) geometry. The NC effects are modeled through a semiclassical approach equivalent to an NC gauge theory, resulting in an effective metric featuring an additional off-diagonal ((r - \phi)) component. Focusing on massless Dirac fields, we compute the QNM frequencies using the continued fraction method, refined via Gaussian elimination to handle the resulting six-term recurrence relations. The analysis reveals significant modifications in both oscillation frequencies and damping rates compared to the commutative Reissner-Nordström case. Notably, the QNM spectrum exhibits a Zeeman-like splitting behavior induced by the NC parameter, highlighting the potential of NC geometry to probe quantum gravity effects in black hole physics.

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9

Theoretical Physics Letters
2025 ° 19(10) ° 0690-10990
https://www.wikipt.org/tphysicsletters
DOI: https://doi.wikipt.org/101490/7700990110990tpl

Article Rating by Readers 10

Noncommutative geometry, Quasinormal modes, black hole, theoretical physics, modern physics

New Elementary Particle Hypothesis: Yin–Yang Particles

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11 Maart 2025 om 06:30:00

New Elementary Particle Hypothesis: Yin–Yang Particles

For centuries, we have sought to identify the fundamental particles that make up the universe, culminating in the Standard Model, which includes over sixty elementary particles such as fermions and bosons. However, the model fails to clearly demonstrate the connections among these particles, raising doubts about whether they are truly the basic building blocks of the universe.

This article introduces a new theoretical framework: Yin–Yang particles, which are proposed to be more fundamental than those in the Standard Model and capable of explaining gravity and electromagnetic transduction. Inspired by Taoist philosophy, which emphasizes the duality of Yin (darkness) and Yang (brightness), this theory presents these particles with distinct interpretations.

The proposed framework aims to clarify various physical phenomena, including light, electrons, quarks, black holes, and electromagnetic waves. While purely hypothetical, it offers a compelling perspective on the nature of the universe.

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7

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Theoretical Physics Letters
2025 ° 11(03) ° 0690-9887
https://www.wikipt.org/tphysicsletters
DOI: https://doi.wikipt.org/10.1490/77009901.9887tpl

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7

elementary particle;, gravity, electron model, quark model, black hole

A Unifying Bag Model of Composite Fermionic Structures in a Cold Genesis Theory of Particles

10.1490/77009901.265tpl

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28 November 2024 om 06:30:00

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A Unifying Bag Model of Composite Fermionic Structures in a Cold Genesis Theory of Particles

The paper presents a better calculation of the constants P_(〖si〗^0 ) and  of the CGT’s unifying bag model, previously published, which explains the strong interaction and the nuclear force without concept of ‚color charge’ specific to the Standard Model. The recalculation indicates that the pressure of internal ‚naked’ photons on the bag’s surface of radius ai = 0.59, which explains the nucleon's quarks deconfining
temperature (2x1012 K), for a current quark's radius of ordinary nuclear temperature: rq = 0.2 fm, is: Psi0(ai) = 6.688x1033 N/m2, corresponding to a ,bag' constant: Bi l= 41.8 MeV/fm3, value which verify the CGT's model of strong ' interaction between quarks and that between nucleons considered in a vertical model, by a constant of the bag's field variation of value:  = 0.34 fm. The total potential of interaction between two nucleons results in the form of a modified Sombrero-type potential, with an attractive part= Va(r) = Va0e-r/* and a repulsive part: Vr(r) = Vr0e-7r/, ( = 0.8 fm). The explanatory model indicates the existence of a bag pressure for each composite particle but also for quarks and the bag’s constant variation with the mass and the intrinsic temperature of the particle’s kernel.

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8.7

http://10.1490/77009901.568tpl

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10

Theoretical Physics Letters
2024 ° 28(11) ° 11-12
https://www.wikipt.org/tphysicsletters
DOI: 10.1490/77009901.265tpl

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8.7

bag model, strong interaction, quarks confining, nuclear interaction, vortical proton model

Detection of the large-scale tidal field with galaxy multiplet alignment in the DESI Y1 spectroscopic survey

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21 Augustus 2024 om 10:15:00

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Detection of the large-scale tidal field with galaxy multiplet alignment in the DESI Y1 spectroscopic survey

We explore correlations between the orientations of small galaxy groups, or “multiplets”, and the large-scale gravitational tidal field. Using data from the Dark Energy Spectroscopic Instrument (DESI) Y1 survey, we detect the intrinsic alignment (IA) of multiplets to the galaxy-traced matter field out to separations of 100ℎ
−1Mpc. Unlike traditional IA measurements of individual galaxies, this estimator is not limited by imaging of galaxy shapes and allows for direct IA detection beyond redshift 𝑧 = 1. Multiplet alignment is a form of higher-order clustering, for which the scale-dependence traces the underlying tidal field and amplitude is a result of small-scale (< 1ℎ −1Mpc) dynamics. Within samples of bright galaxies (BGS), luminous red galaxies
(LRG) and emission-line galaxies (ELG), we find similar scale-dependence regardless of intrinsic luminosity or colour. This is promising for measuring tidal alignment in galaxy samples that typically display no intrinsic alignment. DESI’s LRG mock galaxy catalogues created from the AbacusSummit N-body simulations produce a similar alignment signal, though with a 33% lower amplitude at all scales. An analytic model using a non-linear power spectrum (NLA) only matches the signal down to 20ℎ −1Mpc. Our detection demonstrates that galaxy clustering in the non-linear regime of structure formation preserves an interpretable memory of the large-scale tidal field. Multiplet alignment complements traditional two-point measurements by retaining directional information imprinted by tidal forces, and contains additional line-of-sight information compared to weak lensing. This is a more effective estimator than the alignment of individual galaxies in dense, blue, or faint galaxy samples.

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10

https://doi.wikipt.org/10/1490/77009901/567tpl

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10

Theoretical Physics Letters
2024 ° 22(08) ° 11-11
https://www.wikipt.org/tphysicsletters
DOI: 10.1490/77009901.568tpl

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10

: data analysis, cosmology, large-scale structure of Universe, dark energy

Citation (0)

26 Junie 2024 om 13:15:00

Violation of γ in Brans-Dicke gravity

The Brans Class I solution in Brans-Dicke gravity, discovered in 1961, is a pivotal element in the examination of gravitational theories extending beyond General Relativity. This solution characterizes the external vacuum of a spherical Brans-Dicke star and is distinguished by two adjustable parameters. Notably, a rigorous establishment of the relationship between these parameters and the star's properties is currently lacking. In this work, we endeavor to address this gap by deriving the comprehensive exterior solution of Brans Class I, articulated in relation to the total energy and total pressure of the spherically symmetric gravity source. This derived solution facilitates the precise computation of all post-Newtonian parameters in Brans-Dicke gravity for the distant field regions of a spherical source. Specifically, we obtain an alternative analytical expression for the γ parameter, denoted as γ exact = ω+1+(ω+2) Θ ω+2+(ω+1) Θ, where Θ represents the ratio of the total pressure P∗∥ + 2P∗⊥ to the total energy E∗ contained within the mass source. Our non-perturbative γ formula is universally applicable across varying field strengths and types of matter comprising the mass source. As a result, observational constraints on γ concurrently establish limits on ω and Θ. Significantly, the latter serves as a global characteristic of the mass source. On a broader scope, our formula underscores the significance of pressure (when Θ ̸= 0) in spherical Brans-Dicke stars and potentially in stars within other modified theories of gravitation.

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10

https://doi.wikipt.org/1490/774565/871tpl

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10

Theoretical Physics Letters
2024 ° 026(06) ° 11-10
https://www.wikipt.org/tphysicsletters
DOI: 10.1490/77009901.567tpl

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10

Brans-Dicke gravity, astrophysics, gama, modern physics, theoretical physics

Observations and detectability of young Suns’ flaring and CME activity in optical spectra

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4 Junie 2024 om 09:30:00

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Observations and detectability of young Suns’ flaring and CME activity in optical spectra

The Sun’s history is still a subject of interest to modern astrophysics. Observationally constrained CME rates of young solar analogues are still lacking, as those require dedicated monitoring. We present medium resolution optical spectroscopic monitoring of a small sample of bright and prominent solar analogues over a period of three years using the 0.5m telescope at observatory Lustbühel Graz (OLG) of the University of Graz, Austria. The aim is the detection of flares and CMEs from those spectra. In more than 1700 hours of spectroscopic monitoring we found signatures of four flares and one filament eruption on EK Dra which has been reported in previous literature, but we complementarily extended the data to cover the latter phase. The other stars did not reveal detectable signatures of activity. For these non-detections we derive upper limits of occurrence rates of very massive CMEs, which are detectable with our observational setup, ranging from 0.1 to 2.2 day−1 , but these may be even smaller than the given rates considering observational biases. Furthermore, we investigate the detectability of flares/CMEs in OLG spectra by utilizing solar 2D Hα spectra from MEES solar observatory. We find that solar-sized events are not detectable within our observations. By scaling up the size of the solar event, we show that with a fractional active region area of 18% in residual spectra and 72% in equivalent width time series derived from the same residuals that solar events are detectable if they had hypothetically occurred on HN Peg.

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8

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9.5

Theoretical Physics Letters
2024 ° 04(06) ° 11-09
https://www.wikipt.org/tphysicsletters
DOI: 10.1490/774565.871tpl

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8

stars, chromospheres, flare, late-type, EK Dra, Coronal Mass Ejections

Non-Hermitian unidirectional routing of photonic qubits

2 April 2024 om 07:15:00

Non-Hermitian unidirectional routing of photonic qubits

Efficient and tunable qubit unidirectional routers and spin-wave diodes play an important role in
both classical and quantum information processing domains. Here, we reveal that multi-level neutral
cold atoms can mediate both dissipative and coherent couplings. Interestingly, we investigate and
practically implement this paradigm in experiments, successfully synthesizing a system with dual
functionality as both a photonic qubit unidirectional router and a spin-wave diode. By manipulating
the helicity of the field, we can effectively balance the coherence coupling and dissipative channel,
thereby ensuring the unidirectional transfer of photonic qubits. The qubit fidelity exceeds 97.49 ±
0.39%, and the isolation ratio achieves 16.8 ± 0.11 dB while the insertion loss is lower than 0.36 dB.
Furthermore, we show that the spin-wave diode can effectively achieve unidirectional information
transfer by appropriately setting the coherent coupling parameters. Our work not only provides
new ideas for the design of extensive components in quantum network, but also opens up new
possibilities for non-Hermitian quantum physics, complex quantum networks, and unidirectional
quantum information transfer.

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8

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9.5

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8

Electronic and thermal sequential transport in metallic and superconducting two-junction arrays

10.1490/466489.476tpl

Citation (0)

5 Maart 2024 om 19:00:00

Electronic and thermal sequential transport in metallic and superconducting two-junction arrays

The description of transport phenomena in devices consisting of arrays of tunnel junctions, and the experimental confirmation of these predictions is one of the great successes of mesoscopic physics. The aim of this paper is to give a self-consistent review of sequential transport processes in such devices, based on the so-called ”orthodox” model. We calculate numerically the current-voltage (I–V ) curves, the conductance versus bias voltage (G–V ) curves, and the associated thermal transport in symmetric and asymmetric two-junction arrays such as Coulomb-blockade thermometers (CBTs), superconducting-insulator-normal-insulator-superconducting (SINIS) structures, and superconducting single-electron transistors (SETs). We investigate the behaviour of these systems at the singularity-matching bias points, the dependence of micro refrigeration effects on the charging energy of the island, and the effect of a finite superconducting gap on Coulomb-blockade thermometry.

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10

https://doi.wikipt.org/11/1490/3728tpl

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9

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10

Electronic and thermal sequential, superconducting two-junction arrays, superconductor, tunnel junction, solid state devices, applied physics

Tunable structure-activity correlations of molybdenum dichalcogenides (MoX2; X=S, Se, Te) electrocatalysts via hydrothermal methods: insight into optimizing the electrocatalytic performance for hydrogen generation

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25 Februarie 2024 om 06:30:00

Tunable structure-activity correlations of molybdenum dichalcogenides (MoX2; X=S, Se, Te) electrocatalysts via hydrothermal methods: insight into optimizing the electrocatalytic performance for hydrogen generation

Hydrogen Evolution Reaction (HER) has always gained wide attention as one of the eco-friendly and sustainable pathways for efficient hydrogen generation and storage; also, two-dimensional molybdenum dichalcogenide (MoX2, where X stands for S, Se, Te) layers have emerged as a class of quasi-ideal electrocatalysts because of their large surface area, rich reserves and outstanding conductivity. However, besides greater HER activity, the maturity and diversity of modification strategies result in a more puzzling relationship between electrocatalytic mechanisms and the corresponding practical performance. In this article, based on a comprehensive review of fundamentals, principles and interconnected similarities of the MoX2 family, we focus on the structure-activity correlation of layered MoX2 for HER enhancement via hydrothermal synthesis. This method is summarized from different experimental systems to efficiently modulate the crystal structure and surface for boosted HER activity. Here, with the adjustment of three key experimental parameters: the categories of MoX2, reaction temperature and the molar amount of added reactants, the optimum HER performance can be obtained at the best conditions (MoSe2 species, 180℃ and a vast ratio of the reductant or metal precursor), and more microscopically, a controlled structure-activity relationship can be inducted. This summary may pave a new path for the controllable synthesis and modification of MoX2-based catalyst materials.

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8

https://doi.wikipt.org/11/1490/874831tpl

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10

Theoretical Physics Letters, 2023 ° dd(mm) ° 6584-6621
https://www.wikipt.org/tphysicsletters
DOI: doi.wikipt.org/11/1490/3728tpl

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8

molybdenum dichalcogenides, structure-activity analysis, tunable, phase transition, active sites, hydrogen evolution;, hydrothermal

Probing supermassive black hole seed scenarios with gravitational wave measurements

Citation (0)

6 Desember 2023 om 12:15:00

Probing supermassive black hole seed scenarios with gravitational wave measurements

The process whereby the supermassive black holes populating the centers of galaxies have been assembled remains to be established, with the relative importance of seeds provided by collapsed Population-III stars, black holes formed in nuclear star clusters via repeated mergers, or direct collapses of protogalactic disks yet to be determined. In this paper we study the prospects for casting light on this issue by future measurements of gravitational waves emitted during the inspirals and mergers of pairs of intermediate-mass black holes, discussing in particular the roles of prospective measurements by LISA and the proposed atom interferometers AION and AEDGE.

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10

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10

Theoretical Physics Letters
2023 ° 18(06) ° 0631-3657
https://www.wikipt.org/tphysicsletters
DOI: https://doi.wikipt.org/11/1490/874831tpl

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10

primordial black holes, supermassive black hole, : galaxies – polarization, large-scale structure of Universe

Protoplanetary disks in Ks-band total intensity and polarized light

doi.wikipt.org/10/1490/3486tpl

Citation (36)