bluuebunny/crossref_metadata_2025_split huggingface dataset:
Critical points with prescribed energy for a class of functionals depending on a parameter: existence, multiplicity and bifurcation results
Authors: Ramos Quoirin Humberto , Siciliano Gaetano , Silva Kaye 
Published: April 2024

Abstract
We look for critical points with prescribed energy for the family of even functionals

Φ
μ

=

I
1

−
μ

I
2

, where

I
1

,

I
2

are C
1 functionals on a Banach space X, and

μ
∈

R

. For a given

c
∈

R

and several classes of

Φ
μ

, we prove the existence of infinitely many couples

(

μ

n
,
c

,

u

n
,
c

)

such that

Φ

μ

n
,
c

′

(
±

u

n
,
c

)

=
0

and

Φ

μ

n
,
c

(
±

u

n
,
c

)

=
c

∀
n
∈

N

.

More generally, we analyse the structure of the solution set of the problem

Φ
μ

′

(
u
)

=
0
,

Φ

μ

(
u
)

=
c

with respect to µ and c. In particular, we show that the maps

c
↦

μ

n
,
c

are continuous, which gives rise to a family of energy curves for this problem. The analysis of these curves provide us with several bifurcation and multiplicity type results, which are then applied to some elliptic problems. Our approach is based on the nonlinear generalized Rayleigh quotient method developed in Il’yasov (2017 Topol. Methods Nonlinear Anal.
49 683–714).
Contrail or chemtrail? Challenges and opportunities for educators
Authors: Tupec Vojtěch , Šlégrová Leontýna , Šlégr Jan 
Published: April 2024

Abstract
Debunking conspiracy theories is a never-ending battle. These theories often suggest that the condensation trails left by jet aircraft are, in fact, chemical or biological agents intentionally dispersed for various purposes. Although any discussion with supporters of conspiracy theories is pointless, this paper outlines several potential strategies for incorporating this theory into physics education. Specifically, the concept of ‘chemtrails’ can be leveraged to introduce basic principles of thermodynamics, facilitate the construction of atmospheric models, analyze readily available data, and, importantly, underscore the significance of critical and scientific thinking, which is so important for students these days.
Second harmonic generation in Harmonic-Gaussian asymmetric double quantum well: effect of magnetic and intense laser fields
Authors: Tuzemen A Turker , Demir M , Dakhlaoui H , Mora-Ramos M E , Ungan F 
Published: April 2024

Abstract
We have theoretically analyzed the effects of externally applied fields (magnetic and intense laser) as well as various structural parameters such as well width, barrier width, barrier height, and structural asymmetry on the second harmonic generation (SHG) coefficients of GaAs/Al0.3Ga0.7As Harmonic-Gaussian asymmetric double quantum wells (QW). The time-independent Schrödinger equation was solved using the diagonalization method and effective mass approximation to obtain the energy eigenvalues and eigenfunctions of the structure. An expression derived within the compact density matrix approach has been used to evaluate the second harmonic generation (SHG) coefficient. Our numerical results indicate that increasing the magnitude of the magnetic (intense laser) field causes the peak positions of SHG to shift towards higher energy regions/blue (lower energy regions/red). On the other hand, as the structural parameters

A

1

and

A

2

(

k

and

z

0

) increase, the peak positions of the SHG coefficients exhibit a shift towards higher energy regions/blue (lower energy regions/red). We expect that the results of our study will contribute to the development of new optoelectronic devices based on the Harmonic-Gaussian asymmetric double quantum well structure.
Positive incentive CNN structure coupled nonconvex model for image super-resolution
Authors: Liu Jingjing , Shi Yuying , Ni Guoxi 
Published: April 2024

Abstract
This paper studies super-resolution (SR) technique to reconstruct high-quality images for deep image analysis. Currently, the convolutional neural networks (CNNs) are well performing methods and the finding that random noise added in the network can have positive incentive effect, we innovatively propose a positive incentive CNNs. However, concerning the uncontrollable characteristic and lack consistency of deep network, we propose a novel framework that joins nonconvex model based on framelet and positive incentive CNN structure, which can impose consistency between the high-resolved image and the given low-resolution image, and depict image information by sparse representation. Furthermore, to overcome the challenge of computing the minimizer of the nonconvex problem, we use proximal linearized minimization (PLM) algorithm to convex the nonconvex term, then apply the alternating direction method of multipliers (ADMM) as the solver which can converge to a stationary point of the nonconvex model. The experimental outcomes on Set5, Set14, BSD100, Urban100, and real-world images demonstrate that the proposed approach outperforms the state-of-the-art methods in terms of peak signal to noise ratio (PSNR) value, structural similarity index (SSIM), and visual quality.
Thermo field dynamics on BTZ spacetime
Authors: Rojas C W A , Arenas S J R 
Published: April 2024

Abstract
A thin dust shell contracting from infinity to near its gravitational radius r
+, in a spacetime AdS
3 is analyzed; its equation of motion is determined and the solution R(t) as seen by a FIDO observer is estimated. It is concluded that this Shell's exterior looks like a BTZ black hole with similar properties. Based on the Thermo Field Dynamics technique, a scalar field Φ in the proximity of a non-rotating BTZ (2 + 1) black hole is studied. From the corresponding Killing-Boulware

0

KB
*

and Hartle-Hawking

0

HH
*

vacuum states, the associated Wightman function

W

x
,
x
′

HH

*

−
W

x
,
x
′

KB

*

is determined and based on it, the time component of the momentum-energy tensor of the system

∂

0

∂

0
′

W

HH

*

−

W

KB

*

(
x
,
x
′
)
≈

T

00

(
x
,
x
′
)

=
σ
(
r
)

is calculated. Which allows establishing the origin and location of the degrees of freedom responsible for the entropy that describes a source for the Bekenstein-Hawking S

BH
entropy. The thermal environment described by this model manifests itself with a well-defined and concentrated energy density near the event horizon, according to a FIDO observer.
Black hole solutions with constant Ricci scalar in a model of Finsler gravity
Authors: Nekouee Z. , Narasimhamurthy S.K. , Pacif S.K.J. 
Published: April 2024

Abstract
Ricci scalar being zero is equivalent to the vacuum field equation in Finsler
space-time. The Schwarzschild metric can be concluded from the field equation's solution if the
space-time conserves spherical symmetry. This research aims to investigate Finslerian
Schwarzschild-de Sitter space-time. Recent studies based on Finslerian space-time geometric models
are becoming more prevalent because the local anisotropic structure of space-time influences the
gravitational field and gives rise to modified cosmological relations. We suggest a gravitational
field equation with a non-zero cosmological constant in Finslerian geometry and apprehend that the
presented Finslerian gravitational field equation corresponds to the non-zero Ricci scalar. In
Finsler geometry, the peer of spherical symmetry is the Finslerian sphere. Assuming space-time to
conserve the “Finslerian sphere” symmetry, the counterpart of the Riemannian sphere (Finslerian
sphere) must have a constant flag curvature (λ). It is demonstrated that the Finslerian
covariant derivative of the geometric part of the gravitational field equation is preserved under
a condition using the Chern connection. According to the string theory, string clouds can be
defined as a pool of strings made due to symmetry breaking in the universe's early stages. We find
that for λ ≠ 1, this solution resembles a black hole surrounded by a cloud of strings.
Furthermore, we investigate null and time-like geodesics for λ = 1. In this regard, the
photon geodesics are obtained that are the closest paths to the photon sphere of the first photons
visible at the black hole shadow limit. Also, circular orbit conditions are obtained for the
effective potential.
Probing the impact of delta-baryons on nuclear matter and non-radial oscillations in neutron stars
Authors: Kalita Probit J. , Routaray Pinku , Ghosh Sayantan , Kumar Bharat , Agrawal B.K. 
Published: April 2024

Abstract
Non-radial oscillations of Neutron Stars (NSs) provide a means to learn important details regarding their interior composition and equation of state. We consider the effects of Δ-baryons on non-radial f-mode oscillations and other NS properties within the Density-Dependent Relativistic Mean Field formalism. Calculations are performed for Δ-admixed NS matter with and without hyperons. Our study of the non-radial f-mode oscillations revealed a distinct increase in frequency due to the addition of the Δ-baryons with upto 20% increase in frequency being seen for canonical NSs. Other bulk properties of NSs, including mass, radii, and dimensionless tidal deformability (Λ) were also affected by these additional baryons. Comparing our results with available observational data from pulsars (NICER) and gravitational waves (LIGO-VIRGO collaboration), we found strong agreement, particularly concerning Λ.
Effectiveness of activated zeolite adsorber in decreased soot emission and increased oxygen concentration from combustion smokes of polyvinyl chloride plastic
Authors: Banurea Rahmadhani , Purwanti Eva , Syahrina Maulia , Buysang Luke Gilbert , Rachmad Humam Rafi 
Published: April 2024

Abstract
Polyvinyl Chloride plastic waste is becoming an increasingly urgent global environmental issue. Combustion PVC plastic waste can have significant negative impacts on human health. To overcome these problems, this research was conducted by utilizing zeolite as an adsorbent for PVC combustion smokes. The research methodology is zeolite activation, adsorber design and gas adsorption process through dry adsorption method which is the core of this research. This study will evaluate oxygen concentration and soot emissions. Before being given a zeolite adsorbent, the oxygen concentration produced in PVC combustion smokes was only 17.2% with high soot levels as evidenced by the blackened smoke color. Furthermore, after being given an adsorbent in the form of activated zeolite as much as 283.5 grams, the oxygen concentration produced increased significantly to 20.9% followed by a decrease in soot emission levels as evidenced by changes in the color of whitened smoke. Based on the test results related to the increase in oxygen concentration and the decrease in soot emission levels, it can be concluded that activated zeolite has a high effectiveness in carrying out the PVC combustion smoke adsorption process by producing particles of carbon and oxygen within the normal threshold in the air.
Significant Potential of Cocos nucifera L. Bunches Waste as Carbon Source for Sustainable Electrode Material Supercapacitors
Authors: Pratiwi S , Putra R M , Martin A , Mubarak M , Suwondo S , Halim E H , Taer E 
Published: April 2024

Abstract
The interest in utilizing biowaste materials to produce carbon source, especially for electrode materials in physicochemical energy storage devices like Li-ion batteries and supercapacitors, is driven by concerns regarding energy cost-effectiveness and environmental pollution. This study specifically concentrates on the utilization of waste from Cocos nucifera L. bunches as an eco-friendly source of carbon source designed for supercapacitor electrodes. The precursors chosen in this study were old Cocos nucifera L. bunches and young Cocos nucifera L. bunches. The preparation involves chemical activation of the waste using a 0.5 M potassium hydroxide solution at 900°C, with pyrolysis occurring in an nitrogen and carbon dioxide gas environment. The resultant activated carbon, configured as monolithic coins, retains its structure by optimizing the bonding characteristics of the precursor, eliminating the necessity for supplementary adhesives. Every coin-shaped monolith displays carbon structures ranging from turbostratic to highly amorphous. Electrochemical testing in a symmetric supercapacitor showed old Cocos nucifera L. bunches a high specific capacitance of 262 F g−1 at a constant density of 1.0 A g−1. Furthermore, the maximum energy density was determined to be 3.54 Wh kg−1 at an optimal power density of 85 W kg−1 in 1 M H2SO4 aqueous electrolyte. Utilizing waste, combined with a straightforward preparation process and remarkable electrochemical properties, positions carbon source derived from aged Cocos nucifera L. bunches as a prospective and sustainable electrode material for energy storage applications in supercapacitors.
Elaeis guineensis Jacq.waste-derived as an supercapacitor electrode material with low cost and environmentally friendly
Authors: Taer Erman , Yanti Novi , Rini Ari Sulistyo , Farma Rakhmawati , Muhammad Juandi , Rianna Martha , Awitdrus Awitdrus , Taslim Rika 
Published: April 2024

Abstract
The increasingly rapid development of environmentally friendly porous activated carbon (AC) materials has attracted the attention of researchers. Moreover, the material can be produced from organic waste which is abundantly available. This time, porous active carbon based on green material (palm frond waste) has been successfully prepared and characterized. The application of more efficient, environmentally friendly and cost-effective, methods and production instrument has been optimized in this research. Integrated pyrolysis with carbonization (N2; 600 °C) and physical activation (H2O; 800 °C) produces activated carbon with a high purity level of up to 80 %. Through reviewing N2 gas absorption, it was confirmed that palm frond AC has a specific surface area of 356 m2 g−1, with a rough morphological structure and very rich surface nanopores. Furthermore, XRD characterization confirmed the purity of carbon through good amorphorosity properties with the presence of two wide peaks at diffraction angles of 22-24° and 42-44°. These findings show that the development and innovation of activated carbon production that is more environmentally friendly and cost-effective from palm frond waste is capable of producing active carbon with extraordinary physical characteristics. This palm tree AC has high potential for developing applications such as as an absorption material in air purifiers and water purifiers. Apart from that, these extraordinary characteristics also make palm frond AC suitable for use as electrode material in components of energy storage devices, supercapacitors with specific capacitance 86 F g−1.
Silica Sol as a Filler in Process of Materializing Mullite Fiber (SiO2.Al2O3)
Authors: Sinuhaji Perdinan , Wismogroho Agus S , Lumban Gaol Isac Mangantar T 
Published: April 2024

Abstract
Research has been carried out on the effect of adding silica sol as a filler in making mullite fiber (SiO2.Al2O3). The process of making mullite fiber is carried out using the cast molding method. Sample preparation of (I)silica sol and alumina fiber. (II) silica sol with alumina fiber and kaolin. (III) alumina fiber with kaolin and distilled water. Then the samples were mixed until homogeneous in their respective containers. Then printed in a PVC pipe measuring 2.81 cm in diameter and 1.5 cm high. Mullite fiber samples were dried at a temperature of 110°C for 1 hour, then sintered at a temperature of 1200°C, 1300°C, 1400°C, 1500°C. The density of mullite fiber increases linearly, the porosity decreases linearly, and the compressive strength of mullite fiber increases linearly as the sintering temperature increases. XRD characterization shows that in the three mullite fiber samples the same phase appears, namely mullite, sillimanite has an orthorhombic structure, and cristobalite has a tetragonal structure.
Experimental investigation on ceramic materials of wood flour and bentonite
Authors: Rianna Martha , Harahap Regina Aperita Lusiana , Ananda Novira , Situmorang Putri Cahaya , Sembiring Timbangen , Sianturi Herty Afrina , Amiruddin Erwin , Hussain Muhammad Khalid , Setiadi Eko Arief , Tetuko Anggito P. , Sebayang Perdamean 
Published: April 2024

Abstract
In this research, the solid-state reaction method obtained experimental investigation on wood flour and bentonite ceramic materials. The bentonite of 3 g and the wood flour of 7 g were mixed in a glass beaker and then activated at a temperature of 500°C for 2 hours. Next, the powder was ground using ball milling at 500 rpm for 30 minutes. Characterization uses XRD, SEM with mapping, and Fourier transforms infrared. Results show that the XRD confirmed having silica or SiO2 peaks in crystal structure and composition. The obtained morphological properties of the material are almost cubic with uniform size. FTIR results showed a single bond between silica and oxide. Therefore, wood flour and bentonite are proven ceramic materials because they have stable SiO2.
High-order genuinely multidimensional finite volume methods via kernel-based WENO
Authors: May I C T , Lee D 
Published: April 2024

Abstract
In this paper a family of fully multidimensional kernel-based reconstruction schemes for use in finite volume methods (FVMs) will be presented. These methods are intended for use in shock dominated problems, and stability is achieved through a suitable adaptation of the Adaptive Order Weighted Essentially Non-Oscillatory (WENO-AO) method to the proposed kernel-based reconstruction schemes. There are a number of key difficulties in the design of high-order finite volume schemes which will be discussed and addressed. High (4th and 6th) order convergence will be demonstrated on smooth exact solutions of the ideal MHD equations. The very same scheme will then be applied to extremely stringent astrophysical benchmark problems.
GanESS: detecting coherent elastic neutrino-nucleus scattering with noble gases
Authors: Simón A. ,   the GanESS experiment
Published: April 2024

Abstract
The recent detection of the coherent elastic neutrino-nucleus scattering (CEνNS) opens the possibility to use neutrinos to explore physics beyond standard model with small size detectors. However, the CEνNS process generates signals at the few keV level, requiring very sensitive detecting technologies for its detection. The European Spallation Source (ESS) has been identified as an optimal source of low energy neutrinos offering an opportunity for a definitive exploration of all phenomenological applications of CEνNS.

GanESS will use a high-pressure noble gas time projection chamber to measure CEνNS at ESS in gaseous Xe, Ar and Kr. Such technique appears extraordinarily promising for detecting the process, although characterization of the response to few-keV nuclear recoils will be necessary. With this goal, we are currently commissioning GaP, a small prototype capable of operating up to 50 bar. GaP will serve to fully evaluate the low energy response of the technique, with a strong focus on measuring the quenching factor for the different noble gases that will later be used at GanESS. An overview of the GanESS project with a focus on the status of GaP and its short-term plans is presented.
Towards a fiber barrel detector for next-generation high-pressure gaseous xenon TPCs
Authors: Soleti S.R. ,   the NEXT collaboration
Published: April 2024

Abstract
The NEXT (Neutrino Experiment with a Xenon TPC) project is an international collaboration aimed at finding evidence of neutrinoless double beta decay using gaseous xenon. The current phase of the project involves the construction and operation of NEXT-100, which is designed to hold 100 kg of xenon at 15 bar and is expected to start commissioning in the first quarter of 2024. NEXT-HD will be a tonne scale experiment following NEXT-100 and will incorporate a symmetric design, with one cathode and two anodes. For this detector, the collaboration is considering to implement a barrel of wavelength-shifting fibers read-out by silicon photomultipliers to measure the energy of the particles interacting in the gaseous xenon. In this document, we will discuss the characteristics of this approach and provide an update on the related R&D efforts.
Proton spectroscopy for 11B(p,α)2α fusion reaction with RCF films: calibration and unfolding procedure
Authors: Guarrera M. , Petringa G. , Milluzzo G. , Catalano R. , Kantarelou V. , Siragusa C. , Midili F. , La Cognata M. , Guardo L. , Lattuada D. , Passarello D. , Angemi G. , Arjmand S. , Cantone G. , Caruso E. , Cuttone G. , Farokhi F. , Fattori S. , Giampiccolo O. , Giuffrida L. , Kurmanova A. , Margarone D. , Oliva D. , Pappalardo A. , Pizzino A. , Schillaci F. , Sciuto A. , Suarez J. , Cirrone G.A.P. 
Published: April 2024

Abstract
The reaction occurring between protons and 11B isotope (p+11B → 3α+8.7 MeV) has recently attracted attention as a possible candidate to overcome the generation of high-energy neutrons via the more studied Deuterium-Tritium fusion reaction. Since the early 2000s, several experiments have been carried out to investigate the viability of triggering this aneutronic reaction in laser-target interaction schemes. During these experiments, the total number of escaping α particles is measured to infer fusion reaction efficiency. However, the accurate detection of α particles in such experiments poses a real challenge.

In this scenario,
RadioChromic Films
(RCFs) arranged in a stack configuration can be used for the fluence and energy spectra reconstruction of generated protons, being this mandatory information in both “pitcher-catcher” and “in plasma” p-11B irradiation schemes. Nevertheless, RCF response exhibits a dependence on Linear Energy Transfer (LET), which leads to an underestimation of the response in high-LET conditions. This can result in dosimetric errors if not properly taken into account.
In this work, an analytical procedure able to reconstruct the incident energy spectra in an RCF stack was developed and validated thanks to a calibration procedure that was established for high and low proton energy (4–60 MeV) beams to properly reconstruct the incident spectra in the “pitcher-catcher” irradiation scheme.
Spectrum of coherent VUV radiation generated by 5.7 MeV electrons in a multilayer X-ray mirror
Authors: Shevelev M.V. , Uglov S.R. , Vukolov A.V. 
Published: April 2024

Abstract
The spectral and angular properties of diffracted transition radiation (DTR) and parametric radiation (PXR) in the ultrasoft X-ray region generated by the periodic structure upon interaction with a relativistic electron beam with energy of 5.7 MeV are numerically studied using a sample of the periodic structure [Mo/Si]50, known as a multilayer X-ray mirror. Based on calculations, an experimental approach is proposed to separate and identify the contributions of PXR and DTR. The ultrasoft X-ray radiation can be used to eliminate coherent effects occurring in the optical range when diagnosing the submicron electron beam size.