bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of gender on secondary school physics students’ learning difficulties in electricity
Authors: Adeduyigbe Adeniyi Michael , Ukoh Edidiong E , Okeke Uchenna Kingsley 
Published: February 2025

Abstract
This study investigates the influence of gender on learning difficulties in electricity among senior secondary school physics students in Ondo State, Nigeria. A descriptive survey research design was adopted for the study, and data were collected from 300 students and 30 physics teachers across selected schools via the simple electric circuit diagnostic test and the teacher survey on gender differences in learning electricity. The analysis utilized both descriptive and inferential statistics. The findings indicate that a significant proportion of the students experienced difficulties with various electricity concepts, with notable gender differences in reported difficulties. Furthermore, these identified gender differences in learning difficulties and confidence levels significantly impacted academic performance in electricity concepts. The study concludes with recommendations for implementing targeted instructional strategies, enhancing confidence-building activities, promoting collaborative learning environments, and providing professional development for teachers. These measures aim to create a more inclusive and effective learning environment that addresses learning difficulties in electricity.
Silent physics animation tasks for learner narration
Authors: Harksen Bjarki , Harksen Matthias 
Published: February 2025

Abstract
We introduce silent video tasks for physics education by providing a practical definition of silent physics animation tasks. The original idea of working with silent video tasks is grounded in social constructivist theories and involves students adding their narration to a ready-made silent animation video. We provide a collection of silent physics animation videos created with Manim and explain their content. We examine and reflect on the results of a pilot-study where we analysed the word-frequency of student narrations.
Interactive method for measuring the thermal conductivity coefficient of metals using the LabVIEW platform
Authors: Budinská Zuzana , Svoboda Šimon 
Published: February 2025

Abstract
The aim of this work is to design a user-friendly, illustrative, but also sufficiently accurate experimental setup for the measurement and data analysis, specifically for the determination of the thermal conductivity coefficient of a metal sample. The comparative method was chosen for the measurements, the reference sample was made of aluminium and the measured samples were made of steel and bronze. The measurement data evaluation is performed using LabVIEW software. The results correspond to the tabulated values for these materials, the deviations are less than 1.5%. In addition, a thermal camera can be used in the experiment, which makes the measurement even more illustrative. This method can be used, for example, in teaching in physics laboratories in high schools and technical universities.
Primordial black hole hot spots and out-of-equilibrium dynamics
Authors: Gunn Jacob , Heurtier Lucien , Perez-Gonzalez Yuber F. , Turner Jessica 
Published: February 2025

Abstract
When light primordial black holes (PBHs) evaporate in the early Universe, they locally reheat the surrounding plasma, creating hot spots with temperatures that can be significantly higher than the average plasma temperature.
In this work, we provide a general framework for calculating the probability that a particle interacting with the Standard Model can escape the hot spot. More specifically, we consider how these hot spots influence the generation of the baryon asymmetry of the Universe (BAU) in leptogenesis scenarios, as well as the production of dark matter (DM). For leptogenesis, we find that PBH-produced right-handed neutrinos can contribute to the BAU even if the temperature of the Universe is below the electroweak phase transition temperature, since sphaleron processes may still be active within the hot spot. For DM, particles emitted by PBHs may thermalise with the heated plasma within the hot spot, effectively preventing them from contributing to the observed relic abundance. Our work highlights the importance of including hot spots in the interplay of PBHs and early Universe observables.
An analysis of the longitudinal structure function at next-to-leading orderapproximation at small-$x$
Authors: Boroun G.R. , Cai Yanbing 
Published: February 2025

Abstract
The longitudinal structure function is considered at the&#xD;next-to-leading order approximation using the expansion method, as&#xD;defined by M.B.Gay Ducati and P.B.Goncalves [Phys.Lett.B {\bf390},&#xD;401 (1997)] and further developed by Jingxuan Chen et al.,&#xD;[Chin.Phys.C {\bf48}, 063104 (2024)]. This method provides results&#xD;for a wide range of $x$ and $Q^2$ values. It is observed that&#xD;the behavior of the longitudinal structure function depends on&#xD;the fractional momentum carried by gluons at low $x$. The&#xD;extracted longitudinal structure functions $F_{L}(x,Q^2)$ are in&#xD;line with data from the H1 Collaboration [V. Andreev et al. (H1&#xD;Collaboration),&#xD;Eur. Phys. J. C 74, 2814 (2014)] and the CT18 parametrization method [T.-J. Hou et al., Phys. Rev. D 103, 014013 (2021)]. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.
Techno Study of “Waste to Electric” with Woodchip Pellet Feedstock Through Multi-Stage Gasification in Dual Fuel Diesel Engine
Authors: Hasanuddin  , Bambang S , Toriki M B 
Published: February 2025

Abstract
The increasing demand for energy in various sectors means that energy sources can no longer depend on fossil energy sources, the number of which is decreasing. The decline in fossil energy supply has increased the development of environmentally friendly renewable energy sources, such as biomass. The biomass raw material used is woodchips which has the characteristics of water content 8.4%, volatile solid 74.19%, ash content 1.34%, carbon content 16.07%, hydrogen content 0.0479%, nitrogen 0.4372%, carbon monoxide 0.1701%, methane 0.049%, oxygen 0.1622% and a heating value of 3,907 Kcal/kg. Processing biomass into syngas is carried out through a gasification process. Gasification is the process of converting woodchips into syngas in the form of a gas phase using a three-stage gasification method. Furthermore, the syngas is used as fuel in a dual-fuel diesel engine combined with biodiesel fuel. In this research, a 5 kW diesel engine was used as an experimental tool to determine the performance produced by a dual-fuel diesel engine when dual fuel is injected, namely biodiesel and syngas. The gasifier used in the gasification process of woodchips biomass raw materials has the best water ratio characteristics between the pyrolysis, oxidation and reduction zones, namely 1:7:2. The results of tests that have been carried out with an air ratio setting of 1:7:2 can produce the best diesel engine performance with a stable engine speed value of 3000 rpm and the average voltage at each change in load is 250 volts. Load variations for dual-fuel diesel engine testing are carried out from a load of 0 watts to a load of 4,500 watts. With an increase of every 500 watts. The syngas injection method from the gasifier into the combustion chamber uses 1 variation value, namely full opening (100%). Testing with 100% syngas valve opening resulted in higher average values of engine temperature, exhaust gas temperature and oil temperature compared to other openings. Apart from that, the test results of a 5000-watt engine with dual fuel mode (biodiesel and syngas) were scaled up when applied to the Kolaka PLTD engine which has a capacity of 529 kW. From the calculation results, the value of the savings for using diesel fuel on a 529 kW PLTD engine is Rp. 225,900,975 per month. The initial investment cost is IDR. 1,279,068,380. Meanwhile, the annual income is Rp. 2,445,374,002 assuming Capacity Factor (CF 70%). So the Break Event Point (BEP) value is less than 2 years. Apart from that, a decrease in decarbonization value was also produced by utilizing syngas from woodchip biomass as fuel in a dual-fuel engine with a capacity of 529 kW, resulting in 21.25 tonnes of CO2/year or Rp. 637,431.2
Analysis and Design of Floating PV Systems in Several Batam Reservoirs for Optimizing the Renewable Energy Mix
Authors: Octario B , Dwiyantoro B A 
Published: February 2025

Abstract
The climate crisis caused by the use of fossil fuels is prompting countries around the world to shift to renewable energy. Indonesia has substantial solar energy potential, but this must be balanced with land conservation efforts. The floating PV system is an alternative solution to this problem. This study aims to design a floating solar power generation system at Tembesi and Mukakuning Reservoirs in Batam, focusing on solar energy potential, energy production, and system design. The results indicate that solar irradiation at both locations reaches 1,650 kWh/m2/year with an average horizontal PSH of 4.52 hours/day and net PSH Modules of 4.32 hours/day. Energy production in Year-1 is 55.83 GWh with a performance ratio of 81.65%, resulting in annual energy production of 1,345 kWh/kWp. The floating PV system design at Tembesi and Mukakuning Reservoirs consists of 10 islands, each with 19 array boxes and 20 strings per array box, comprising 28 PV modules per string. A total of 106,400 PV modules with a capacity of 390 Wp each is utilized. The system employs 3,125 kVA PV inverters, 7,500 kVA MV transformers, and 35 MVA HV transformers to ensure high efficiency and reliability. The system design also considers environmental durability, including resistance to corrosion and water level fluctuations. Recommendations include optimizing the design based on seasonal variations and implementing effective monitoring and maintenance systems.
Efficiency of Eggshell Waste as a Metal Corrosion Inhibitor SS316L Based on Green Technology in Seawater Media
Authors: Alfattah M , Arwati I G A , Arramel  , Afkauni A A , Yofatama R M 
Published: February 2025

Abstract
Utilizing eco-friendly inhibitors offers an effective approach to combat pipe corrosion, as focus has increasingly turned towards options that are cost-effective, environmentally benign. The research investigates the application of waste from domestic chicken eggshells as a corrosion inhibitor. The objective of this study is to evaluate the effectiveness, morphology, and chemical properties of 316L stainless steel when treated with these eggshell-based inhibitors. The study employed several techniques, including EPD coating, potentiodynamic polarization, SEM, and Raman spectroscopy in seawater. The findings indicated that the lowest corrosion rate was observed in specimens treated with a 14g inhibitor concentration, with an average rate of 6.24883×10−4 mmpy with the efficiency 96.09%. Analysis SEM revealed that the sample without any inhibitors exhibited numerous small cavities on its surface. In contrast, the sample with a 14g inhibitor concentration showed a reduction in these cavities and a darker surface appearance due to the presence of a layer of adsorbed eggshell powder. Raman spectroscopy of the samples treated with 14 grams of eggshell powder, the final product of corrosion has disappeared, but there is still a α-FeOOH feature and its intensity is greatly reduced. drastic. This signifies that the use of an eggshell coating has effectively prevented corrosion.
Experimental study and performance analysis of direct coupled solar vapor compression refrigeration system
Authors: Setiawan R R , Ambarita H , Sitorus T B , Sihombing H V , Malau R H 
Published: February 2025

Abstract
The solar powered vapor compression refrigeration system with or without load was experimentally studied and analyzed. The results showed that the refrigeration system can work normally with a DC compressor working time of 8 hours, the refrigeration system can reach a temperature of -6.9°C and 2.9°C respectively at no-load and with-load conditions. The COP obtained was 3.094 and 2.786 respectively at no-load and with-load conditions. The average efficiency of the photovoltaic solar panel is known to be 10.94% and 10.69% respectively at no-load and with-load conditions. The results of the sizing calculation for the refrigeration system without a cooling load required a 150Wp photovoltaic solar panel, a 12V 42Ah battery and a 20A solar charge controller. While when the refrigeration system works with a load, a 200Wp photovoltaic solar panel, a 12V 50Ah battery and a 20A solar charge controller are required.
Synthesis and characterization of zirconium alloy by spark plasma sintering (SPS)
Authors: Desiati R D , Hermanto B , Afghani F A , Suharno B , Mochtar M A , Sudiro T 
Published: February 2025

Abstract
Zirconium alloys are widely applied as nuclear fuel cladding materials due to its excellent neutron transparency. However, a major challenge in developing this material is the strong affinity of Zirconium to Hydrogen, Oxygen, and Nitrogen. Therefore, precise techniques and processing parameters are essential for fabricating this alloy. In this study, Zr-alloy according to the Zircaloy-4 composition has been synthesized using a Spark Plasma Sintering (SPS). For this purpose, we used the commercially available Zr powder with alloying materials such as Sn, Cr, and Fe. The powders were mixed and wet milled using a shaker mill for 30 minutes and dried to evaporate a process control agent. The mixture powder was then consolidated using a SPS method under vacuum conditions at a sintering temperature of 900 °C with a heating rate of 50 °C/min and a holding time of 5 min. XRD and SEM-EDS were applied to investigate the phase composition, microstructure, and elemental analysis of the powder and sintered alloy. In addition, the density and hardness of the sintered Zr-alloy were also evaluated. The results show that the high density of Zr-alloy (6.59 g/cm3) with a hardness of about 566.05 HV is successfully synthesized using a SPS technique. The alloy comprises α-Zr and ZrH2 with fractions of 88.1% and 11.9%, respectively. A comprehensive analysis of the results will be presented and discussed in the forthcoming paper.
Evaluation of HDPE plastic waste as a coarse aggregate substitute in Hot Rolled Sheet-Wearing Course asphalt mixtures
Authors: Desriantomy D , Siantoni J , Murniati M 
Published: February 2025

Abstract
Plastic-based goods are commonly used in daily life, but their waste poses significant environmental challenges due to its durability. This study investigates the use of recycled plastic as an artificial coarse aggregate in asphalt mixtures, specifically assessing the effects of High-Density Polyethylene (HDPE) on Hot Rolled Sheet Wearing Course (HRS-WC) mixtures. The objectives are to evaluate the physical properties of the artificial coarse aggregates, identify the optimal asphalt content and Marshall characteristics, and determine the maximum feasible substitution level for these aggregates. A test specimen (briquette) was produced for the Marshall test to assess the mixture properties. Our findings indicate that the maximum allowable substitution of HDPE plastic in HRS-WC mixtures is 42%. With an optimal asphalt content of 7.30%, HDPE substitution levels of 30%, 35%, 40%, 45%, and 50% yielded the highest stability at 45% (1176.696 kg), the highest VMA at 30% (21.250%), and the highest VIM within specifications at 30% (4.998%). The highest VFB value was observed at 45% (88.767%), while the highest Marshall Quotient was at 30% (364.527 kg/mm). The study recommends a maximum HDPE plastic waste substitution level of 40%, highlighting the potential for using HDPE plastic waste in asphalt mixtures to promote more sustainable construction practices.
Effect of ring baffles in simulated flue gas denitrification via NH3-SCR in fluidized bed reactor: A CFD approach
Authors: Rosales B R , Mendoza J A 
Published: February 2025

Abstract
An unsteady Eulerian-Eulerian CFD model was employed in ANSYS FLUENT 19.2 to assess the impact of ring baffles on the hydrodynamics and NO removal efficiency in a fluidized bed reactor using the NH3-SCR process and CuO/ɤ-Al2O3 as catalyst. Initial simulations of the baffle-free (FFB) reactor were validated against experimental data focusing on bubble diameter and NO removal efficiency. Kinetic parameters were adjusted following mesh optimization to align with the experimental findings. Subsequently, simulations were conducted on baffled (BFB) reactors. The introduction of ring baffles markedly improved NO removal efficiency under identical operating conditions as the FFB. Notably, at 573.15 K, baffle configurations D7, T3, and T6 achieved removal efficiencies of 92.40%, 92.19%, and 92.36%, respectively. Even at a lower temperature of 523.15 K, these setups maintained high efficiencies indicating that baffled reactors could replicate FFB performance at reduced temperatures. The study highlights that ring baffles increase solid holdup and radial gas velocity, particularly beneath the baffles, fostering improved gas-solid interactions. Furthermore, the granular temperature was significantly enhanced by the presence of baffles.
Lightweight rotating machinery fault diagnosis based on quadratic convolutional neural network and evidence fusion of multi-source sensor information
Authors: Wang Shanshan , Han Wenkang , Zhang Hao , Zeng Liang 
Published: February 2025

Abstract
Rotating machinery is the core component of various modern equipment. Timely and accurate fault detection is of great significance to ensure the safe operation of mechanical equipment and the stability of production efficiency. Deep learning-based methods have triggered a boom in the field of machinery fault diagnosis. However, due to factors such as noise interference in industrial applications, an increase in accuracy is often accompanied by an increase in computational cost, leading to difficulties in deploying the model in engineering applications. In order to find a balance between robustness and complexity, this paper proposes a lightweight intelligent fault diagnosis framework called (QSMC-EFN). Firstly, a new nonlinear quadratic neural network is used to extract features initially and then combined with a multiscale separable convolutional block to extract multiscale features of the vibration signal. Different features from multiple scales are subsequently fused using a statistical Dempster-Shafer (DS) theory of evidence, fed into a lightweight feature extraction layer consisting of multi-scale separated convolution and broadcast attention mechanisms to gain further the ability to extract more critical features. Through experiments on the planetary gearbox and variable speed bearing datasets, it is verified that the proposed fault diagnosis system ensures effectiveness while also achieving a lightweight model.
Non-magnetic glass-fiber cryostat for MADMAX prototype tests
Authors: Kreikemeyer-Lorenzo D. , Koettig T. , Borges de Sousa P. , Gooch C. , Kittlinger D. , Majorovits B. , Maldonado J.P.A. , Pralavorio P. 
Published: February 2025

Abstract
MADMAX, an axion dark matter search experiment, is currently
in the prototype testing phase. Its working principle is based on
the conversion of axions in a magnetic field into photons. This
signal is then enhanced by a booster made of dielectric disks placed
in front of a mirror. In order to test MADMAX prototypes at
cryogenic temperatures in a magnetic field parallel to the disks, a
new G-10 glass-fiber cryostat of 0.06,m3 inner volume was
designed, tested and used in a CERN magnet. The design allows to
minimise cost as well as cooling down and warming up times. Using
continuous circulation flow of gaseous helium, the MADMAX prototype
was cooled down reproducibly to temperatures below 10 K for more
than 24 hours. This procedure allowed, for the first time, to
perform a calibration of the booster response and to run a dark
matter axion search in a magnetic field at low temperatures. This
novel type of cryostat, with a low manufacturing cost, fast and easy
to operate, could be used for other purposes beyond MADMAX.
Vortex lattices and critical ﬁelds in anisotropic superconductors
Authors: Speight Martin , Winyard Thomas 
Published: February 2025

Abstract
A method is developed to compute minimal energy vortex lattices in a general Ginzburg-Landau model of a superconductor subjected to an applied magnetic field. The model may have any number of components and may be spatially anisotropic. The novelty of this method is that it makes no assumptions about the orientation of the vortex lines or the period vectors of the lattice's unit cell: these are all determined dynamically. Methods to compute the first and second critical magnetic fields, $H_{c_1}$ and $H_{c_2}$, in this class of models are also developed.&#xD;&#xD;These methods are applied to a simple anisotropic single-component model, and to an anisotropic two-component model of strong current theoretical interest (a so-called $s+id$ model). It is found, in both cases, that at low applied field the vortex lines can tilt very significantly away from the direction of the applied field (by as much as $40^\circ$ for the single-component and $30^\circ$ for the $s+id$ model). The optimal lattice in the $s+id$ model is qualitatively very different from the conventional triangular Abrikosov lattice, exhibiting a phase transition from a system of Skyrmion chains when the external field is orthogonal to the basal plane to a deformed Abrikosov lattice when applied in the basal plane.