bluuebunny/crossref_metadata_2025 huggingface dataset:
A highly stable LaCo0.75Fe0.25O3 perovskite catalyst supported on a ceramic monolith used for chlorobenzene combustion
Authors: Perez Hector Acosta , Durán Flavia G. , Cadús Luis E. , Agüero Fabiola N.
Published: December 2024

The LaCo0.75Fe0.25O3-supported perovskite catalyst resulted in excellent catalytic performance and stability at 200 hours.
Oriented catalysis through chaos: high-entropy spinels in heterogeneous reactions
Authors: Mo Yalan , Guan Xiaohong , Wang Shaobin , Duan Xiaoguang
Published: December 2024

This review provides an overview of the advances in high entropy spinel oxides in diverse catalytic reactions and highlights the intrinsic structure–property–performance relationships.
Improving the bioactivity and mechanical properties of poly(ethylene glycol)-based hydrogels through a supramolecular support network
Authors: Liu Yuzhu , Islam Md Shariful , Bakker Anna , Li Zihao , Ajam Alaa , Kruzic Jamie J. , Kilian Kristopher A.
Published: December 2024

Poly(ethylene glycol) (PEG)-based hydrogels are brittle and bioinert. Incorporating a bioactive self-assembling tryptophan zipper (trpzip) peptide during polymerization enhanced bioactivity, durability and self-healing properties.
Flexible Cu(In,Ga)Se2 photovoltaics for bending applications: advances from materials to panels
Authors: Park Ha Kyung , Jo William
Published: December 2024

This review covers the progress and applications of flexible CIGS solar cells from lab research to commercialization, emphasizing methods for evaluating mechanical flexibility and bending-induced phenomena.
Two-dimensional multiferroicity and half-metallicity of the carrier-doped 2H-VSiN3 monolayer
Authors: Gong Long , Liu Ming-Yang , He Yao , Xiong Kai
Published: December 2024

Two-dimensional (2D) multiferroicity is realized by carrier doping in 2H-VSiN3 monolayer.
A novel fuzzy approach for winding paper insulation health monitoring of oil‐immersed power transformer using non‐destructive failure parameters
Authors: Nezami Md. Manzar , Hashem Hythem , Equbal Md. Danish , Khan Shakeb A. , Malik Hasmat , García Márquez Fausto Pedro , Afthanorhan Asyraf , Hossaini Mohammad Asef
Published: December 2024

Power transformers, a significant and critical component of power system, require regular condition monitoring by the utilities for uninterrupted power supply. The kraft paper made of cellulose is used as the solid insulation of the transformer which undergoes thermal, electrical and environmental stresses causing its progressive ageing. It thereby reduces the physical strength of the paper and ultimately affects the transformer's remaining useful life (RUL). The current state (physical) of the cellulosic (solid) insulating paper is predicted in this article using the fuzzy inference system (FIS) based RUL assessment technique. Three non‐destructive parameters, that is, 2‐Furfuraldehyde (2‐FAL), Carbon Monoxide (CO) and Carbon dioxide (CO2) are used to determine the value of the Degree of Polymerisation (i.e. DP) which directly reflects the current physical state of the insulating material. Four states (Healthy, Poor, Very Poor, and Worst) of the insulating paper are identified based on the values of DP. Five FIS models have been developed separately with different membership functions and a number of fuzzy if‐then rules are formulated to estimate the value of DP. Every model is tested with 30 test samples to validate the system accuracy. The physical condition of the insulation estimated using FIS built with trapezoidal membership function has been found to be considerably precise with an average absolute deviation of 0.33%. Hence, a comprehensive assessment of transformer's health is carried out with the prominent non‐destructive parameters.
Are stellar embryos in Perseus radio-synchrotron emitters?
Authors: Bracco Andrea , Padovani Marco , Galli Daniele , Pezzuto Stefania , Cipriani Alexandre , Drabent Alexander
Published: December 2024

Cosmic rays (CRs) are crucial to the chemistry and physics of star-forming regions. By controlling the ionization rate of molecular gas, they mediate the interaction between matter flows and interstellar magnetic fields, thereby regulating the entire star formation process, from the diffuse interstellar medium to the formation of stellar embryos, or cores. The electronic GeV component of CRs is expected to generate nonthermal synchrotron radiation, which should be detectable at radio frequencies across multiple physical scales. However, synchrotron emission from star-forming regions in the Milky Way has barely been observed to date. In this work, we present the first attempt to statistically detect synchrotron emission with the LOw Frequency ARray (LOFAR) at 144 MHz from the nearby Perseus molecular cloud (at a distance of ~300 pc). We perform median stacking over 353 prestellar and 132 protostellar cores derived from the Herschel Gould Belt Survey. Using data from the LOFAR two meter sky survey (LoTSS) with an angular resolution of 20″, we identify 18 potential protostellar candidates and 5 prestellar ones. However, we interpret these as extragalactic contamination in the Herschel catalog. Our statistical analysis of the remaining cores does not reveal any significant radio counterpart of prestellar and protostellar cores at levels of 5 μJy beam−1 and 8 μJy beam−1 in the stacked maps, respectively. We discuss our non-detections in two ways. For protostellar cores, we believe that strong extinction mechanisms of radio emission, such as free-free absorption and the Razin–Tsytovich effect, may be at play. For prestellar cores, using analytical models of magnetostatic–isothermal cores, the lack of detection with LOFAR helps us constrain the maximum ordered magnetic-field strength statistically attainable by these objects, on the order of 100 μJG. We predict that the statistical emission of the prestellar-core sample in Perseus seen by LoTSS should be detectable in only 9 hours and 4 hours with the Square Kilometre Array-Low (SKA-Low) array assemblies AA* and AA4, respectively.
Two-dimensional charge layer at the boundary between two insulators
Authors: Kovdrya Yu. Z.
Published: December 2024

The properties of excess electrons in insulators near the boundary with a vacuum or another insulator are discussed. If the bottom of the conduction band of an insulator is below the energy level of an electron in a vacuum or the bottom of the conduction band of another insulator in contact with it, then the excess electrons can be pressed to the interface by an external electric field. In this case, a two-dimensional electron layer forms near the interface at sufficiently low temperatures, and also a high electron mobility. The energy spectrum of electrons in such a layer is shown to be oscillatory and the spacing between energy levels is determined by the magnitude of the electric field and the dielectric constants of the media.
Anisotropy of quantum diffusion of 3He in hcp 4He
Authors: Slyusarev V. A. , Strzhemechnyi M. A.
Published: December 2024

Within the framework of the known hopping approximation we calculate the diffusion coefficient D with allowance for the hcp symmetry and the anisotropic impurity–impurity interaction potential. The estimated value 20.5 cm3/mole for the specific volume indicates that the values of D along the c axis and in the basal plane differ by a factor of almost three.
Possibility of surface superfluidity in parahydrogen crystals
Authors: Shevchenko S. I.
Published: December 2024

This paper is an attempt to explain the recently observed phenomenon of gravity-induced flow of solid parahydrogen. The proposed explanation is based on the assumption that at temperatures below 3 K (when the flow effect is observed) the surface layers of the parahydrogen are superfluid. The superfluid surface phase resembles a two-dimensional phase and thus vortices are easily formed in it. In the presence of vortices the force of gravity causes a steady-state flow in the surface layer and the velocity of this flow determines the mass flow. The mass flow rate found within the framework of the model of a superfluid surface layer is of the same order of magnitude as that observed experimentally.
Quantum diffusion in hydrogen–deuterium solid solutions
Authors: Minchina I. Ya. , Bagatskii M. I. , Manzhelii V. G. , Krivchikov A. I.
Published: December 2024

Configurational relaxation in H2–D2 solid solutions with 2–30 mole % deuterium and 0.2–1.0 mole % orthohydrogen is investigated calorimetrically over the temperature range 0.5–3 K. The temperature and concentration dependences of the characteristic relaxation time τ are found.
Interaction of two multielectron dimples on a liquid helium surface
Authors: Krasnyĭ Yu. P. , Mikho V. V.
Published: December 2024

An attempt is made to describe approximately the interaction between two multielectron dimples on a liquid helium surface. Taking account of the fact that the dimensions of the dimples are not too small compared with the equilibrium distance between them, shows that dimples can be bound at a distance of the order of several capillary wavelengths from one another. The charge localization spots of different dimples do not then overlap.
Characteristic features of the current–voltage and voltage–field characteristics of 2H-NbSe2 single crystals in the temperature range 5–7.2 K
Authors: Obolenskii M. A. , Beletskii V. I. , Chashka Kh. B. , Sokolov A. N.
Published: December 2024

The current–voltage (I–V) and volt–field (V–H) characteristics of a layered NbSe2 superconductor have been investigated at temperatures below the critical point Tc in an Itr ⊥ H geometry (Itr is the transport current and H is the intensity of the external field) and an Itr ⊥C6 geometry (C6 is a sixfold axis perpendicular to the plane of the layers). The experimentally observed temperature and field peak effects are explained within the framework of the Kim–Anderson model.
Anomalies in the thermal conductivity of the layered crystal CsDy(MoO4)2
Authors: Anders É. E. , Volchok I. V. , Zvyagin A. I. , Kokshenev V. B. , Startsev S. V.
Published: December 2024

Features of the temperature dependence of the thermal conductivity ϰ(T) of the layered crystal CsDy(MoO4)2 have been studied in the temperature range 30–330 K, which includes structural phase transitions. Possible mechanisms for the origin of the practically temperature-independent behavior of ϰ(T) over a wide temperature range are discussed. A mechanism of coherent phonon scattering by electronic excitations of dysprosium ions in the high-temperature phase (Tc = 42 K) is proposed.
Rovibrationally resolved Rayleigh and Raman scattering cross sections for molecular hydrogen
Authors: Singor Adam J. C. , Scarlett Liam H. , Zammit Mark C. , Bray Igor , Fursa Dmitry V.
Published: December 2024

Accurate Rayleigh and Raman scattering cross sections, tensor components, depolarization ratios, and reversal coefficients for all rovibrational transitions within the X1Σg+ ground electronic state of H2 have been calculated. Raman spectra have been generated using these data. A method for calculating Raman scattering cross sections is formulated that is valid below the ionization threshold and in the region containing resonances, which explicitly accounts for all bound and dissociative vibrational levels of the bound intermediate electronic states and approximately accounts for the ionization continuum. A representative set of cross sections is presented for incident photon energies below 15 eV and compared with existing results in the literature where possible. Convergence of our results with an increasing number of bound intermediate electronic states is demonstrated. The accuracy of the Placzek–Teller approximation is discussed. The effect of accounting for the intermediate ionization continuum is investigated. Local thermal equilibrium cross sections are calculated for Rayleigh and Raman scattering. This work represents the most accurate and complete treatment of Raman scattering for molecular hydrogen to date. A total of 9582 Rayleigh and Raman scattering cross sections have been generated and are openly available on Zenodo under an open-source Creative Commons Attribution license at https://zenodo.org/doi/10.5281/zenodo.13441471.
The well-posedness of axially symmetric compressible subsonic cavity flow
Authors: Wang Xin
Published: December 2024

In this paper, we investigate the existence and uniqueness of the three-dimensional axially symmetric steady compressible subsonic flow behind an obstacle. It is shown that there exists a critical value Mcr > 0 such that if the total incoming mass flux M0 is less than Mcr, then there exists a unique subsonic cavity flow, with the free boundary smoothly emanating from the endpoint of the obstacle and having a constant end pressure along the free boundary. Moreover, the positivity of the radial velocity and the asymptotic behavior of the cavity flow at far field are also obtained. As a by-product, the convexity of the free boundary is derived. Based on the convex geometry property of the free boundary, we obtain the positivity of the axial velocity in the fluid. If the free boundary is strictly convex, it is further proved that the optimal regularity of the free boundary at the separation point is C1,12.
Influence of transverse structural vibration on the nonlinear dynamics of Rijke-type subcritical thermoacoustic system
Authors: Li Xinyan , Gao Jingtao , Zhang Hao , Shi Baolu , Chen Geng
Published: December 2024

This study numerically investigates the impact of external transverse structural vibration on the nonlinear dynamics of a subcritical thermoacoustic system. A comprehensive analysis is conducted using various methods, including time series analysis, reconstructed phase portrait, spectrum analysis, and wavelet analysis to characterize the system's response. When the thermoacoustic system operates in the globally stable region, the acoustic pressure amplitude exhibits a monotonic increase with the vibration amplitude, with resonant conditions leading to significantly higher system responses compared to non-resonant cases. In the hysteresis region, high-amplitude vibrations are found to trigger thermoacoustic instability at any frequency, with lower heater temperatures requiring higher vibration amplitudes. Under non-resonant conditions, low-frequency vibrations require lower amplitudes to trigger instability compared to high-frequency vibrations. Once the system becomes unstable, external structural vibrations exert a modulating effect on the high-amplitude limit cycle oscillations. The present findings provide valuable insights into the complex interaction between structural vibration and thermoacoustic instability in thermoacoustic systems, advancing the understanding of these phenomena and their implications for the design and operation of practical combustion devices.
Analysis and applications of the upwind conservation element and solution element scheme for compressible flow simulations
Authors: Jiang Yazhong , Shi Lisong , Wen Chih-Yung
Published: December 2024

The upwind conservation element and solution element (CESE) scheme is an alternative discontinuity-capturing numerical approach to solving hyperbolic conservation laws. To evaluate the numerical properties of this spatiotemporal coupled scheme, a formal analysis is conducted on the upwind CESE discretization applied to the linear advection problem. The modified equation and the effective modified wavenumber are derived, which theoretically confirm the order of accuracy and reveal the dissipation and dispersion properties of this scheme. Several examples are considered to demonstrate the capabilities of the upwind CESE scheme for simulating compressible flows, including shock–vortex and shock–bubble interactions. The results of the present scheme agree well with exact solutions, results of other numerical methods, and experimental data. This demonstrates the high resolution of the scheme in capturing shock waves, material interfaces, and small-scale flow structures.
Superconductor to exciton condensate transition in a model copper-oxide material
Authors: Schouten Anna O , Sager-Smith LeeAnn M , Mazziotti David A
Published: December 2024

Superconductivity and exciton condensation are fundamental phenomena in condensed matter physics, associated with the condensation of electron–electron and electron–hole pairs, respectively, into coherent quantum states. In this study, we present evidence of a superconductor to exciton condensate transition within the context of the three-band Hubbard model of copper-oxide-like materials. As the electron–electron repulsion increases, the superconducting phase is superseded by exciton condensation. In support of theoretical predictions—not yet realized experimentally—we observe the coexistence of the two condensates in the vicinity of the transition where the quantum states become a superposition of electron–electron and electron–hole condensates. Coexistence is rigorously computed from large eigenvalues and their eigenvectors in both the two-electron reduced density matrix (2-RDM) and the particle-hole RDM, which we obtain from a direct variational ground-state energy minimization with respect to the 2-RDM by semidefinite programming. We further discern that adjacent d orbitals and intervening p orbitals facilitate electron–electron pairing between copper orbitals, thereby supporting the superexchange mechanism for superconductivity. These observations suggest the feasibility of witnessing a superconductor to exciton condensate transition in copper-oxide analogs, bearing significant implications for identifying materials conducive to efficient transport processes.
Existence and Stability of Implicit Fractional Differential Equations Involving the p-Laplacian Operator and Their Applications
Authors: Khan Rahman Ullah Ullah , Samreen Maria , Ali Gohar , Popa Ioan-Lucian
Published: December 2024

The main objective of this paper is to establish the existence, uniqueness, and stability of implicit fractional differential equations involving a p-Laplacian operator, utilizing the Caputo-Katugampola fractional derivative. A novel approach is employed to examine the existence and uniqueness of solutions to the problem through fixed-point theorems. These results are original and extend several existing findings in the literature. Finally, an application is provided to illustrate the theoretical results.
Leveraging Movement Representation from Contrastive Learning for Asteroid Detection
Authors: Kongsathitporn Noppachanin , Supratak Akara , Noysena Kanthanakorn , Awiphan Supachai , Steeghs Danny , Pollacco Don , Ulaczyk Krzysztof , Lyman Joseph , Ackley Kendall , O’Neill David , Kumar Amit , Galloway Duncan K. , Jiménez-Ibarra Felipe , Dhillon Vik. S. , Dyer Martin J. , O’Brien Paul , Ramsay Gavin , Pallé Enric , Kotak Rubin , Killestein Thomas L. , Nuttall Laura K. , Breton Rene P.
Published: December 2024

To support asteroid-related studies, current motion detectors are utilized to select moving object candidates based on their visualizations and movements in sequences of sky exposures. However, the existing detectors encounter the manual parameter settings which require experts to assign proper parameters. Moreover, although the deep learning approach could automate the detection process, these approaches still require synthetic images and hand-engineered features to improve their performance. In this work, we propose an end-to-end deep learning model consisting of two branches. The first branch is trained with contrastive learning to extract a contrastive feature from sequences of sky exposures. This learning method encourages the model to capture a lower-dimensional representation, ensuring that sequences with moving sources (i.e., potential asteroids) are distinct from those without moving sources. The second branch is designed to learn additional features from the sky exposure sequences, which are then concatenated into the movement features before being processed by subsequent layers for the detection of asteroid candidates. We evaluate our model on sufficiently long-duration sequences and perform a comparative study with detection software. Additionally, we demonstrate the use of our model to suggest potential asteroids using photometry filtering. The proposed model outperforms the baseline model for asteroid streak detection by +7.70% of f1-score. Moreover, our study shows promising performance for long-duration sequences and improvement after adding the contrastive feature. Additionally, we demonstrate the uses of our model with the filtering to detect potential asteroids in wide-field detection using the long-duration sequences. Our model could complement the software as it suggests additional asteroids to its detection result.
Analytical Investigation of Second Harmonic Generation in Metal Nanoparticle Trimers Using Dipole Approximation
Authors: Farhoomand Afsoon , Sepehri Javan Nasser , Kheirandish Asef
Published: December 2024

In this theoretical study, we investigate the generation of second harmonics (SH) during the interaction of a laser beam with a metallic nanoparticle (MNP) trimer. Utilizing a classical electrodynamics framework, we explore the nonlinear interactions between the laser beam fields and nanoparticles (NPs), accounting for dipole-dipole interactions among the particles. Analytical expressions are derived to quantify the impact of these interactions on SH radiation power for two distinct polarizations of the laser beam. Our findings indicate that when the laser electric field is aligned parallel to the trimer's symmetry axis, there is a significant enhancement in SH radiation power compared to a single non-interacting NP, accompanied by a red-shift in the plasmon resonance peak. Conversely, when the laser electric field is perpendicular to the trimer axis, the SH radiation power from each NP decreases, and the plasmon resonance peak experiences a blue-shift. Additionally, we examine the influence of particle size and interparticle separation on SH generation. These results provide valuable insights into the role of interparticle interactions in enhancing nonlinear optical processes in NP assemblies, with potential implications for the design of nanophotonic devices.
Research on Static Security Analysis and Assessment Method of Integrated Energy Systems Based on the Unified Energy Circuit Theory
Authors: Bao Kaiwen , Hu Linxian
Published: December 2024

Multi energy flow coupling is a key feature distinguishing integrated energy systems (IES) from traditional power systems. As the degree of multi energy flow coupling in IES increases, the mutual influence between various energy subsystems becomes more pronounced. Local fluctuations or faults can propagate through different energy flows, thus affecting the overall security and stability of the system. This paper primarily focuses on the static security analysis and assessment methods for integrated energy systems. By utilizing the unified energy circuit model for power, natural gas, and thermal systems, it aims to achieve a unified analysis of heterogeneous energy flows. The paper extends the N-1 static security analysis method from power systems to IES, deeply explores the mechanisms of cross-system fault evolution, investigates fault diagnosis and security analysis techniques, and establishes a security assessment index system for IES. Finally, the effectiveness of the proposed analysis and assessment method is validated through a case study.
Application research of dual-stage coupled heat pump system
Authors: Yuan Jiapu , Wang Yajing
Published: December 2024

In this paper, firstly, the structure and working principle of dual-stage coupled heat pump is introduced, and a detailed introduction to the energy-saving design of the system is provided. Secondly, this article introduces the specific applications of dual-stage coupled heat pumps and obtains their specific energy consumption through field testing. Finally, this article compares the energy consumption of the dual-stage coupled heat pump system with that of boilers and air source heat pumps, and analyzes their energy-saving effects. The results indicate that the heat pump system proposed in this paper has good energy-saving effects. Moreover, it is worth vigorously promoting and using.
Research on the ultrasonic location of transformer local discharge based on super-directivity-MSSA
Authors: Shi Yansheng , Liu Feng , Wang Wei
Published: December 2024

Aiming at the problem of accurately locating the partial discharge source in a transformer, this article will place multiple sensors inside the transformer windings for detection and location, and propose a location method that combines a super-directivity algorithm with a chaotic sparrow search algorithm (MSSA) integrated with multi-directional learning. We use the finite element method to simulate the ultrasonic signals inside the transformer windings. First, we use the super-directivity algorithm to measure the direction of the internal partial discharge source of the transformer, determine the search space of the MSSA algorithm according to the output direction, and solve the position information of the partial discharge source. The simulation results show that this algorithm has a smaller positioning error compared with traditional methods. Finally, we use a new type of EFPI optical fiber sensor to conduct partial discharge location experiments inside the transformer windings. The experimental results show that the positioning accuracy of this method is within 4 centimeters, verifying that this method has practical application value.
Design of a simple broadband high-pass frequency selective surface
Authors: Zhu Mengtong
Published: December 2024

FSS is a widely used spatial filter that can isolate signals in different frequency bands from each other to achieve frequency band separation. In this paper, a hexagonal honeycomb slit cell is used as the centre of the FSS, and the microelement patch and slit-loaded coupled mesh grid structure are utilized to effectively increase the passband bandwidth so as to realize the design of high-pass and low-distortion FSS with wide bandwidth by combining the different structures in a relatively simple way. Finally, the separation of high-frequency and low- frequency signals with good angular and polarization stability is achieved when the TE or TM polarization is incident at 45° angle in 22GHz~58GHz (S
21 ≤ -12.2dB) and 87GHz~124GHz (S
21 ≥ -0.95dB).
Non-intrusive power load decomposition method based on message passing graph neural network
Authors: Huangfu Hancong , Wang Yongcai , Guan Zhaoxiong
Published: December 2024

The non-invasive power load decomposition technology has a relatively small impact on the power system. Besides, it has a strong adaptability to different networks, but its load decomposition shows poor accuracy. To raise the accuracy of non-intrusive power load decomposition methods, a household power load decomposition model with factor hidden Markov model was established, which aims to use a message passing mechanism to improve the graph neural network and solve the power load decomposition model. The outcomes denote that the research design method can realize an F1 Score of 0.9326 and a mean absolute error of 10.24 in power load decomposition. When decomposing the load of commonly used household appliances, the F1 Score of the research design method is higher than other traditional non-intrusive power load decomposition methods. The non-intrusive power decomposition method designed for research has effectively improved the accuracy of existing methods.
Liquid phase exfoliation of α-SnSe nanosheets: Exploring the role of solvents
Authors: Tamuli Stuti , Kar Anubhab , Mohanta Dambarudhar
Published: December 2024

In this study, we used a top-down approach to fabricate 2D SnSe nanosheets via the liquid phase exfoliation (LPE) technique. Bulk SnSe was dispersed in six different solvents: isopropyl alcohol (IPA), absolute ethanol, N-Methyl-2-pyrrolidone (NMP), acetone, methanol, and deionized (DI) water. The solutions containing bulk SnSe were ultrasonicated and subjected to high-speed centrifugation. Comprehensive characterization of both the bulk and exfoliated samples was conducted using various techniques. X-ray diffraction (XRD) analysis confirmed the orthorhombic crystal structure of bulk SnSe. Raman spectroscopy was used to examine the vibrational properties of both bulk and exfoliated SnSe, showing distinct B
3g and A
g
3 modes at ~115.6 and 150 cm−1, respectively. Morphological analysis using both Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM) revealed the formation of few-layer nanosheets. Additionally, UV-visible spectroscopy was employed to investigate the optical properties and the stability of the exfoliated SnSe nanosheets.
Theoretical and Experimental Investigation on Hydrophilicity of Polymeric Membrane
Authors: Das Prince , Kakati Bharat , Hazarika Tonmoi , Pal Dipankar
Published: December 2024

The study employs nitrogen (N2) plasma for surface modification of a polymeric membrane to investigate the changes in its hydrophilic properties under diverse storage conditions. It is found that the hydrophobic recovery of cellulose nitrate membrane for 7 minutes of plasma treatment is moderate for water medium, high for atmospheric medium, and low for vacuum medium. For water medium, this process is governed by fixed dipole-dipole interactions, which dominate over London dispersion forces, limiting hydrophobic recovery. In the atmospheric medium, hydrophobic recovery accelerates due to variations in temperature and relative humidity. In the vacuum medium, hydrophobic recovery is slowed down due to the absence of reactive species influencing recovery. As a result, the diffusion-based theoretical model matched with experimental data for the water and atmosphere mediums but not for the vacuum medium. SEM analysis reveals significant pore enlargement and surface etching of the plasma-facing membrane surface after 7 minutes of plasma treatment compared to untreated membranes. EDX results showed increase in C/N ratio indicating the presence of nitrogen containing functional groups. Since the FTIR penetration depth exceeds the modification depth caused by plasma treatment, similar peaks were observed for both treated and untreated membranes. Several peaks were observed in both treated and untreated samples at 1643 cm-1 (C-C stretch), 1275 cm−1 and 1059 cm−1 (C-O stretch), and 834 cm−1 (C-H bend). AFM analysis shows a significant enhancement in surface roughness for plasma-treated membrane with respect to untreated membrane which is obtained as 32% more than that of untreated membrane.
Study of the Density Parameters of the Dark Energy and the Cosmological Constant in the context of Brans-Dicke Theory
Authors: Choudhury Shaheb , Deb Priya , Bhowmik Anwesha , Debnath Dipa , Ghosh Sovan
Published: December 2024

The discovery of supernova projects at the end of the 20
th
century altered the theory of current cosmology and sparked the hunt for dark energy and dark matter. The time evolution of the density parameter is examined here by considering a test function. Using the Brans-Dicke frame work, the calculations are advanced. The density parameter of dark energy (Ω
D
) and matter (Ω
m
) are connected by mathematical descriptions and found to produce a unit value when Ω
D
and Ω
m
are in fraction. As the calculations are built on the structure of the scale factor, this present article is attempt to describe the framework in terms of scale factor (a) as well. The results coming from the test function model show nice resemblance with known observations. The use of Brans-Dicke theory makes provision for in detail study of Ω
D
and Ω
m
.
Classification of Dark Energy Models
Authors: Ghosh Sovan , Devi Baishali
Published: December 2024

Accelerated expansion is well-defined from the observational redshift. It is found from Type Ia Supernova data that the major share of the energy of the universe is yet to be explained and that prompted the search for dark energy and dark matter. Dark energy is expected to be around 68% of the total energy of the universe. To match with experimental observations different theoretical models of dark energy are proposed over the years. Here it is attempted to classify the models of current scenario.
Modeling of Single and Multi-grid IECF Device to Study Plasma Particle Dynamics
Authors: Bhattacharjee Darpan , Saikia Lucky , Mohanty Smruti Ranjan , Adhikari Sayan
Published: December 2024

During the last two decades, the Inertial Electrostatic Confinement Fusion (IECF) device has gained popularity as a table-top neutron/proton source due to its uncomplicated design and comparatively smaller volume which has the potential of providing high fusion rate. The basic concept of the device is to accelerate lighter ions like deuterium, tritium, etc., to collide and produce fusion-relevant energies by the application of a converging electrostatic field inside a spherical or cylindrical chamber.

In the present work, we have discussed the ion dynamics in a single and triple-grid arrangement of the cylindrical IECF device by making use of an open-source particle-in-cell code known as XOOPIC. A comparative study of ion density and potential profiles has been performed at different input potentials. The simulated outcomes are compared with the experimentally obtained results. A detailed study on the obtained results has been presented here.
Investigation of magnetospheric solitons in the recovery phase of a geomagnetic storm for solar cycle 23 using Cluster II mission
Authors: Sarma Shyamalima , Khusroo Murchana
Published: December 2024

Solitary structures or solitons, prominent nonlinear phenomena in space plasmas, have been extensively studied, particularly in the magnetospheric regime utilizing data from Cluster II mission. This study examines aperiodic magnetospheric oscillations observed during the recovery phase of a geomagnetic storm (GMS), which is a result of magnetic disturbances triggered by coronal mass ejection (CME) or interplanetary mass ejection (ICME) interacting with Earth’s magnetic field, in solar cycle 23. The analysis utilizes data from the Fluxgate Magnetometer (FGM) and Cluster Ion Spectroscopy (CIS) instruments onboard spacecraft C1 and C4 of the Cluster II mission. The analysis identifies a train of aperiodic solitons with increasing amplitudes propagating through the bow shock region of the magnetosphere. This paper provides detailed observations and analytical insights into the formation mechanisms of these aperiodic solitons during geomagnetic storm recovery.
Exploring alpha emissions in neutron induced reactions via QMFT based dynamical cluster-decay approach
Authors: Chhetri Rita , Kaur Amandeep , Singh Birbikram
Published: December 2024

This study theoretically investigates alpha emission from compound nuclei formed in neutron-induced reactions, inspired by the experiments of Yu M. Gledenov et al. at Peking University, China. The research focuses on the decay dynamics of even-mass compound nuclei 144Nd* and 148Sm*, formed with neutron beam energies of 4 to 6 MeV. Employing the Dynamical Cluster-decay Model (DCM) based on Quantum Mechanical Fragmentation Theory (QMFT), high Q-value alpha emission channels 144Nd*→
140Ce+α and 148Sm*→
144Nd+α are explored. Cross-sections for alpha emissions are calculated by optimizing the neck-length parameter “∆R”, showing agreement with experimental data. Given the highly asymmetric incoming channel, the beam energy approximates the centre of mass energy (E
beam≈E
c.m.
). The study evaluates the impact of deformations, considering spherical and quadrupole-deformed configurations of the decaying fragments, and examines the alterations in potential energy surfaces. For deformed fragmentation, orientations are optimized for hot configurations. A comparative analysis of fragmentation structures, preformation profiles, and barrier characteristics is conducted between spherical and quadrupole-deformed fragmentation. The DCM’s collective clusterization approach treats all exit channels equally, emphasizing the formation of the preferred decay channel over competing channels such as fission. Observed changes in fragmentation profiles underscore the influence of nuclear parameters like angular momentum and deformations, providing insights into the dynamics of compound nucleus decay and the pivotal role of these parameters in shaping reaction outcomes.
Estimation of Radon activity in the nuclear security laboratory at the basement level of a building
Authors: Pathan Sohailkhan. S. , Gupta Unnati , Goel Alpana
Published: December 2024

Among all radiation exposure, the second leading cause of lung cancer is Radon while smoking is the primary contributor. The identification of the source and extent of Radon contamination is paramount for the formulation and implementation of measures aimed at reducing Radon levels in indoor spaces. Given the serious health implications, numerous countries and regions have implemented stringent Radon exposure limits and regulations to safeguard public health. The present work is to study the activity of 222Rn within a nuclear education laboratory. For the detection of gamma rays, a High-purity Germanium detector, with 34% relative efficiency and 0.6 mm carbon window was used. However, for the adsorption of Radon activity, 70 g charcoal in metal tin was employed. The spectrum was obtained using PROSPECT software and was calibrated using a 152Eu standard source. The analysis of the spectrum was done using CANDLE. The radionuclides 214Pb, 214Bi, and 40K which have gamma rays of 351keV, 609 keV, and 1460 keV, respectively are investigated. The measured activity of 222Rn radionuclide was found to be ranging between 9.77±0.73 Bq/Kg to14.00±1.00 Bq/Kg.
Development and experimental studies of a light vehicle diesel after treatment system with DOC, DPF and urea SCR
Authors: Thangapandian P. , Paulsingarayar S. , Chandraprakash R. , Seenivasan S. , Vimal Kannan I. , Siddeshwar S.A.
Published: December 2024

Strict adherence to pollution limits poses a risk to light-duty diesel engines due to challenges in post-treatment procedures, product limitations, and emission criteria. This paper aims to determine the underlying principles for the technological development of an after-treatment technique that incorporates a diesel oxidation catalyst (DOC), catalytic Diesel Particle Filter (DPF), urea injector, and catalytic urea selective reduction (SCR). Implementing this selective catalytic reduction (SCR) technique would greatly enhance the catalyst’s ability to convert NOx by regulating the evaporation of urea and avoiding a decrease in exhaust temperature and mixing efficiencies. Moreover, the uniformity of the NH3 concentration distribution over the catalyst surface is advantageous. This study explored the concept of an electrically evaporated urea-dosing device. The investigation revealed that heated urea had a beneficial effect on improving the elimination of NOx from both continuous and intermittent motor operations before its application to the gas exhaust. The cylindrical urea evaporative heating chamber was equipped with a venturi jet that directed urea vapour down the exhaust drain. The urea solution dosing technique, administered by spraying, was a customised method more advantageous than the conventional liquid dosage system.
Tribological, Compressibility and Micro Hardness Behaviour of Al7075/SiC Composites
Authors: Karthikeyan G. , Velmurugan T. , Gandhi V.C. Sathish , Elatharasan G. , Thulasi S.
Published: December 2024

The Al7075 with various weight percentages such as 6%, 9%, and 12% of SiC composites were fabricated by stir casting method. The three samples are subjected to a wear test, compressive test, and microhardness test by using a spin-on disc, Universal Testing Machine (UTM), and vicker harness tester machine. From the results, Al7075 with 12% silicon carbide showed better deformation behavior low wear behavior and high hardness strength. These behaviors of more initial fraction density, and high bore presence of silicon carbide reinforcement than others perform. The stress formability index increases with increasing initial perform fraction density at higher silicon carbide. For the composite with lower values of SiC content and with high initial perform density. From these results observed that the percentage of increasing the reinforcement gives better results compared to the lower reinforced alloy.
Hydroponic IoT-Based Control Using Adaptive Fuzzy, PID, and Consensus Control Methods for Nutrient Concentration Dosing
Authors: Nizam Nurul Aimee Izzaty Mohd , Chung Seng Kheau , Yew Hoe Tung , Kiring Aroland M’conie Jilui
Published: December 2024

One of the seventeen Sustainable Development Goals (SDGs) is to provide zero hunger, achieve food security, enhance nutritional quality, and promote sustainable agriculture. To achieve these goals, food production has to be increased by adopting modern techniques in agriculture, such as hydroponic farming and the Internet of Things (IoT). Effective handling of nutrient concentrations, specifically electrical conductivity (EC) values, is crucial for optimizing plant health and yield. To reduce the challenge posed by high overshooting of nutrient concentration and also due to the diffusion of the regulating liquid fertilizer through the pipeline, the EC value control system demonstrates features such as time-delayed for the nutrient concentration to reach the setpoint. The paper aims to provide a comprehensive study that evaluates three distinct control strategies for regulating nutrient concentration in a hydroponic environment: proportional-integral-derivative (PID) control, fuzzy logic control, and a consensus control algorithm. The stability and performance of these control systems were investigated through simulation analysis and comparative evaluations. The findings indicate that the PID control system is faster in reaching the setpoint, while the fuzzy control system exhibits the least overshoot. Moreover, the consensus algorithm emerges as the most optimal control system in terms of time to reach the setpoint and minimize the overshoot value.
Analysis and Modelling of Waves, Tides and Currents On Sediment Distribution In Banyuasin River Estuary
Authors: Setiawan O , Chalid A , Siregar C A , Rosadi  , Witarsa D R
Published: December 2024

Sedimentation at the mouth of the Banyuasin River is a natural process whereby solid materials such as sand, mud, and other deposits accumulate in areas where the river meets the ocean. This process occurs because the flow of river water laden with solid materials slows down upon entering the calmer waters at the river mouth. By conducting analysis and modeling at the mouth of the Banyuasin River, patterns of sedimentation and the magnitude of sedimentation resulting from the convergence of river currents with waves, tides, and ocean currents at the mouth of the Banyuasin River can be determined. The analysis is performed using quantitative methods, the results of which can identify sedimentation patterns at the mouth of the Banyuasin River by considering several important factors, namely river currents, ocean waves, tidal fluctuations, and ocean currents. Modeling results using the Mike-21 software indicate that sedimentation occurs at various parts of the Banyuasin mouth, with relatively small volume magnitudes. The conclusion from this analysis and modeling is that sediment deposition at the mouth of the Banyuasin River exhibits dynamic stability due to the influence of significant river currents during certain seasons, allowing sediment deposition to occur within a certain period, while at other times, the sediment deposition is carried back by the river currents towards the sea.
A Comparison of Wind Speed Derived from Various Microwaves Satellite in Tropical Cyclone.
Authors: Najwa Ayob Nurul , Sharoni Syarawi M. H. , San Lim Hwee , Raisyha Nurfarain Abdullah Nik
Published: December 2024

Wind speed measurements derived from various microwave satellites, including scatterometers, altimeters, and radiometers, is vital to assess the characters of tropical cyclone (TC). This paper focuses on comparing the differences in wind speed measurements from scatterometers, altimeters, and radiometers, each with inherent limitations. The research utilizes various microwaves satellite data within global tropical cyclone wind and applying univariate analysis to evaluate the range and variation of wind speed distributions. Hurricane Katia (2011) is used as a case study. Findings indicate that different satellite types exhibit varying performances under extreme conditions. The Oceansat-2 scatterometer recorded the highest wind speed (69.24 m/s), while the ERS-2 altimeter showed the lowest (28.5 m/s). In terms of TC characterization, scatterometers excel in identifying TC intensity and structure but lack detail in the TC eye. Radiometers provide broad coverage but are less accurate at high wind speeds, focusing on TC periphery. Altimeters offer precise wind speed data near the eyewall but are limited by narrow coverage and infrequent observations. Combining these data sources provides a more accurate TC characterization, improving monitoring and mitigation. Future research should refine measurement algorithms and integrate more extensive satellite data.
Butterworth Environmental Dataset: Employing COVRATIO for Outlier Detection with Simultaneous Linear Functional Relationship Model
Authors: Ain Al-Hameefatul Jamaliyatul Nur , Amyra Mokhtar Nurkhairany , Badyalina Basri , Rambli Adzhar , Zulina Zubairi Yong
Published: December 2024

The monsoon is affected by factors like wind speed, humidity, and temperature. Outliers can significantly skew the data, and this study presents an outlier detection method using the COVRATIO statistic, derived from the covariance matrix within a simultaneous Linear Functional Relationship Model (LFRM) for linear variables. The cut-off point for the 5% upper percentiles of the maximum value of the COVRATIO statistic is established through a Monte Carlo simulation study. The findings indicate that outliers are detected when the COVRATIO statistic surpasses these cut-off points. The effectiveness of the simultaneous LFRM is demonstrated using Butterworth environmental data, with variables including wind speed, humidity, and temperature. The data s normality is confirmed by the Kolmogorov-Smirnov test. This research supports the National Policy on Climate Change by contributing to knowledge-based decision-making in climate-related studies, particularly in the domains of environmental monitoring, renewable energy planning, and data analysis.