bluuebunny/crossref_metadata_2025 huggingface dataset:
Tailoring selenization dynamics: How heating rate manipulates nucleation and growth boosts efficiency in kesterite solar cells
Authors: Zhu Xuetao , Meng Rutao , Shao Shuai , Feng Liangliang , Shang Liuyang , Liu Hui , Wang Yushan , Guo Hongling , Zhang Yi
Published: January 2025

Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) has emerged as a promising photovoltaic material due to its low cost and high stability. The CZTSSe film for high-performance solar cells can be obtained by annealing the deposited CZTS precursor films with selenium (a process known as selenization). The design of the selenization process significantly affects the quality of the absorber layer. In this work, we systematically investigate the impact of heating rate on the selenization kinetics and the microstructural characteristics of the films using a two-step selenization method. The results indicate that a slow heating rate promotes surface crystallization, resulting in a thick and dense layer of large grains at the film surface that impedes the diffusion of Se vapor. Conversely, a rapid heating rate enhances the diffusion of Se into the interior of the film, synthesizing more low-melting-point intermediate compounds that facilitate grain growth and reduce the thickness of fine grains at the film bottom. Ultimately, a CZTSSe solar cell with an efficiency of 10.17% was fabricated at a heating rate of 200 °C/min. This research deepens the understanding of thin film growth mechanisms and advances the development of high-performance solar cells.
2D Raman-THz spectroscopy of imidazolium-based ionic liquids
Authors: Shukla Saurabh , Shalit Andrey , Hamm Peter
Published: January 2025

An investigation of the low-frequency (i.e., less than 5 THz), inter-molecular dynamics of three imidazolium-based ionic liquids—1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C4mim][NTf2]), 1-butyl-3-methylimidazolium dicyanamide ([C4mim][DCA]), and 1-ethyl-3-methylimidazolium dicyanamide ([C2mim][DCA])—is presented using two-dimensional (2D) Raman-THz spectroscopy combined with molecular dynamics (MD) simulations. By observing an echo in the 2D Raman-THz response, the experimental results indicate that the substitution of a small [DCA]− anion with a larger [NTf2]− one leads to a substantial increase in the structural inhomogeneity of the low-frequency modes of the system. These findings are corroborated by MD simulations, comparing the experimentally observed echo decay times to those of a computed velocity echo. The comparison suggests that the echo decay time reflects the instantaneous amount of structural order related to the charge alternation network, which is enhanced for the ionic liquid with the larger anion.
Temperature and pressure dependence of the fluorescence spectrum of high-pressure synthetic corundum-type Ga2O3:Cr3+, structural stability, and crystal growth under high pressure
Authors: Yusa Hitoshi , Miyakawa Masashi
Published: January 2025

The pressure dependence of the R1 and R2 peaks of the fluorescence spectra of high-pressure-synthesized corundum-type Ga2O3:Cr3+ was measured up to 50 GPa using a diamond anvil cell pressurized at room temperature in an argon medium. The temperature dependence of the R1 and R2 peaks was measured at low temperatures under ambient pressure from 303 to 83 K. From the measurement results, the pressure scale and low-temperature scale were determined using R1 and R2. X-ray diffraction experiments at high pressure, which were performed to confirm the effective range of the pressure scale, showed that the corundum structure undergoes a phase transition to a Rh2O3(II)-type structure at 54–65 GPa; this pressure scale is, thus, valid up to approximately 50 GPa. We also investigated the crystal growth time to optimize the crystal size of Ga2O3:Cr3+ for diamond anvil cell experiments.
Enhancing the accuracy of XPS calculations: Exploring hybrid basis set schemes for CVS-EOMIP-CCSD calculations
Authors: Delgado Alexis A. A. , Matthews Devin A.
Published: January 2025

Reliable computational methodologies and basis sets for modeling x-ray spectra are essential for extracting and interpreting electronic and structural information from experimental x-ray spectra. In particular, the trade-off between numerical accuracy and computational cost due to the size of the basis set is a major challenge, since molecular orbitals undergo extreme relaxation in the core-hole state. To gain clarity on the changes in electronic structure induced by the formation of a core-hole, the use of sufficiently flexible basis for expanding the orbitals, particularly for the core region, has been shown to be essential. This work focuses on the refinement of core-hole ionized state calculations using the equation-of-motion coupled cluster family of methods through an extensive analysis on the effectiveness of “hybrid” and mixed basis sets. In this investigation, we utilize the CVS-EOMIP-CCSD method in combination and construct hybrid basis sets piecewise from readily available Dunning’s correlation consistent basis sets in order to calculate x-ray ionization energies (IEs) for a set of small gas phase molecules. Our results provide insights into the impact of basis sets on the CVS-EOMIP-CCSD calculations of K-edge IEs of first-row p-block elements. These insights enable us to understand more about the basis set dependence of the core IEs computed and allow us to establish a protocol for deriving reliable and cost-effective theoretical estimates for computing IEs of small molecules containing such elements.
AutoTurb: Using large language models for automatic algebraic turbulence model discovery
Authors: Zhang Yu , Zheng Kefeng , Liu Fei , Zhang Qingfu , Wang Zhenkun
Published: January 2025

Symbolic regression (SR) methods have been extensively investigated to explore explicit algebraic Reynolds stress models (EARSM) for turbulence closure of Reynolds-averaged Navier-Stokes (RANS) equations. The deduced EARSM can be readily implemented in existing computational fluid dynamic (CFD) codes and promotes the identification of physically interpretable turbulence models. Recently, large language models (LLMs) trained on large amounts of publicly available source code have drawn great attention for their abilities to automatically discover equations with more general free-text inputs and problem descriptions and provide wider possibilities with novel insights. This work proposes a novel framework, named “AutoTurb,” using LLMs to automatically discover algebraic expressions for correcting the linear Reynolds stress model. The direct Reynolds stress and the indirect RANS output (e.g., velocity field) are both involved in the training objective to guarantee data consistency and avoid numerical stiffness. An evolutionary search framework is used for global optimization, where constraints on functional complexity and simulation convergence are integrated into the objective to manage the extensive flexibility of LLMs. The proposed method is performed for separated flow over periodic hills. The generalizability of the discovered model is verified on a set of 2D turbulent separated flows with different Reynolds numbers and geometries. Results show that the corrected RANS enhances predictions of both Reynolds stress and mean velocity fields. Compared to models from other studies, our discovered model shows superior accuracy and generalization capability. The proposed approach provides a promising paradigm for using LLMs to improve turbulence modeling for a given class of flows.
Dynamic responses of the unbonded composite riser with multi-spacing coupling interference
Authors: Li Peng , Zhu Li , Wang Yu , Liu Zhen , Wang Yeshuo , Gao Lianjie , Huang Yijie , Hao Lianhong
Published: January 2025

The interference among risers has always been a research focus within marine engineering. By riser, we mean the equipment that transports oil, gas, and other fluid media in marine environments, connecting the offshore platform and subsea wellhead. The “unbonded composite riser-smooth riser” serves as the research object of this paper, which experimentally investigates the riser group vibration with multi-spacings. This study reveals the interference mechanism of risers with interlayer slip by reviewing the dynamic response of unbonded composite risers in various arrangements. The results indicate that increasing displacement of a side-by-side unbonded composite riser is subjected to the interference and internal cable interlayer slip at high flow velocities. The displacement interference rate peaks, particularly at S/D = 4 (S/D is the spacing ratio, where S represents the distance between the axis of the two risers and D represents the outer diameter of a riser). By contrast, changes in the spacing ratio have little influence on the dominant frequency. The strong energy dissipation capacity and high mass-damping ratio of side-by-side unbonded composite risers efficiently decrease vibration caused by fluid forces. Side-by-side unbonded composite risers occur in a delayed “lock-in” region as opposed to smooth risers under the same conditions. Furthermore, the wake and clearance flow interference on the unbonded composite riser results in a maximum difference of up to 5 times greater in the average value of displacement interference rate.
The physical mechanisms of plasma directional deflection in cross-coupled arc
Authors: Chen Shujun , Zhang Cheng , Jiang Fan , Zhang Guokai , Li Wenlong , Xu Bin
Published: January 2025

Cross-coupled arcs (CCAs), as a novel heat source, enable decoupled control of heat and mass transfer, offering significant potential in metal processing applications such as additive manufacturing, welding, and surface treatment. To ascertain the primary cause of the main-arc deflection in the CCA, numerical models of the double-wire plasma arc (DW-PA), CCA, and without magnetic coupling for plasma cross-coupled arc (WMC-CCA) were constructed. Through the comparative analysis of the temperature, electromagnetic field, and force field following the calculation of the models, the coupled magnetic field in the CCA is the fundamental cause of the influence of the main-arc deflection. Additionally, the welding parameters in the CCA numerical model are modified to analyze its effect on the extent of main-arc deflection. As the main-arc current and inter-wire current increase, the degree of main-arc deflection concomitantly increases. The center area of the main-arc deflects relatively small because high plasma flow velocity increases the arc stiffness, hindering its deflection to the sides. In addition, the spatial position of the welding wire is another key factor affecting arc deflection.
Enhancing indoor temperature mapping: High-resolution insights through deep learning and computational fluid dynamics
Authors: Sofos Filippos , Drikakis Dimitris , Kokkinakis Ioannis William
Published: January 2025

This paper examines the temperature distribution in a closed, rectangular room equipped with an air conditioning system, employing a computational fluid dynamics model to simulate a virtual thermal camera that captures detailed temperature snapshots. A super-resolution framework enhances the postprocessing of these results. Specifically, convolutional neural networks, trained on simulation data, are used to accurately model temperature fields' high-resolution spatial and temporal evolution. The model demonstrates strong performance by accurately reconstructing temperature profiles from low-resolution inputs obtained from filtering data obtained using high-resolution numerical simulations, with quantitative metrics indicating acceptable accuracy for resolutions reduced by up to 50 times. This effectively aligns with ground truth profiles under various conditions. These results underscore the super-resolution model's potential to transform environmental monitoring in smart buildings and complex structures by generating high-resolution thermal maps from low-resolution cameras or limited sensor input. This approach offers a fast, cost-effective, and reliable method for accurately modeling thermal dynamics within the turbulent flow environments of interior spaces.
Drop impacting on a surface with temperature gradient
Authors: Deng Tao , Kuang Yihan , Liu Liyu , Chen Guo
Published: January 2025

Drop impacts on compound or patterned surfaces have been widely studied as these surfaces can significantly enhance the richness and diversity of outcomes. In this work, a simple preparation strategy for a surface with a temperature gradient is presented, and the impact of ethanol drops on such a surface is systematically investigated. The experiments reveal that the temperature gradient gives rise to a stiffness gradient. Both the temperature and stiffness gradients make the splash phenomenon of a drop more diverse. Moreover, the temperature gradient also leads to changes in the physical properties of the liquid during the drop spreading, resulting in the asymmetrical spreading of a drop. Quantitative results indicate that after a characteristic time, the drop begins to spread faster in the high-temperature region than in the low-temperature region, which is mainly attributed to the lower liquid viscosity of the drop in the high-temperature zone. This work enriches the understanding of drop impacts on heterogeneous surfaces and may also inspire engineers or researchers to discover more interesting physical phenomena by using surface heat treatment techniques.
Simultaneously enhance electric and magnetic Purcell factor by strong coupling between toroidal dipole quasi-BIC and electric dipole
Authors: Tan Zi-Qiang , Lin Qi , Du Wen-Juan , Wang Ling-Ling , Liu Gui-Dong
Published: January 2025

The larger electric or magnetic Purcell factor demonstrates that the structure can be utilized as an electric or magneto-optical emission project. Their simultaneous realization offers the potential for integrated circuits to achieve selective photon sources. In this study, we put forth a proposal for the simultaneous attainment of substantial electrical and magnetic Purcell enhancements. In our hybrid metal–dielectric metasurface, the toroidal dipole (TD) quasi bound states in the continuum mode and the electric dipole (ED) mode are strongly coupled, so the hybrid mode combines the advantages of both, with a large Q factor and a small mode volume. The design implements a Rabi splitting energy of 222 meV between the TD quasi-BIC and ED modes, achieving an electric Purcell factor of 43 and a magnetic Purcell factor of 684, which are greater than those observed for the metal rod and dielectric structure, respectively. This paves the way for the development of high-performance hybrid optoelectronic applications.
Exploring the equilibrium and non-equilibrium properties of a cooperative trinuclear spin-crossover chain: The role of elastic frustration
Authors: Ndiaye Mamadou , Boukheddaden Kamel
Published: January 2025

Among the large family of spin-crossover (SCO) solids, recent investigations focused on polynuclear SCO materials, whose specific molecular configurations allow the presence of multi-step transitions and elastic frustration. In this contribution, we develop the first elastic modeling of thermal and dynamical properties of trinuclear SCO solids. For that, we study a finite SCO open chain constituted of successive elastically coupled trinuclear (A=B=C) blocks, in which each site (A, B, and C) may occupy two electronic configurations, namely, low-spin (LS) and high-spin (HS) states, accompanied with structural changes. Intra- and inter-molecular springs couple the sites inside and between trimers. The model also includes the change of length inside and between the trinuclear units subsequent to the spin states changes. First, we studied the mechanical relaxation of a LS chain initially prepared with HS distances, from which we dissected the dynamics of the atomic displacements for various strengths of intra- and inter-molecular elastic constants. Second, we investigated the thermal properties of the chain at equilibrium, which revealed the existence of a rich variety of behaviors, going from: gradual LS to HS transition to multiple spin transitions with the presence of self-organized spin state structures in the plateaus. The latter were identified as emerging from antagonist short- and long-range elastic interactions between intra- and inter-block size changes. The present model opens several possible extensions, among which are the cases of coupled non-linear trimer molecules as well as that of inter-chain interactions with block–block interactions, leading to unexpected hysteretic spin transitions.
Measurement of capillarity using oblique plates as a function of the separation angle, temperature and glycerol concentration in water
Authors: Cortés S , Fajardo F
Published: January 2025

Capillarity refers to the ability of a liquid to move within narrow spaces such as tubes and pores with reduced diameters or between two oblique plates with a very small angle between them. It is well known that the height a liquid can reach due to capillarity is directly related to the values of the surface tension, the density, and the contact angle. In this investigation, a study is conducted on the dependence of these properties on the glycerol concentration in an aqueous solution and on the water temperature. The experimental device used is a capillary formed by two oblique glass plates, which allows for the direct observation of the liquid height variation as a function of the separation angle between the plates. This phenomenon is studied using Jurin’s law, widely used in the study of capillarity. The results are explained using the Connors–Wright surface tension model and the Eötvös rule. The experiment is very low cost and easy to implement in undergraduate science laboratories, making it useful for exploring the capillarity phenomenon of liquids.
Five-layer gradient structures for improved energy storage performances on the basis of sandwich framework
Authors: Yang Qi , Zhu Jiujun , Hou Yafei , Zhang Qixiong , Cuan Jing , Li Weiping
Published: January 2025

High energy storage performances in multilayer nanocomposites are crucial for the advancement of modern electronic and power systems. However, the large dielectric contrast between adjacent layers leads to an uneven electric field distribution, which hampers the potential for further increasing their energy storage performances. Herein, five-layer gradient-structured nanocomposites were designed and fabricated based on previous sandwich framework by introducing transition layers between the outmost insulation layer and the inner polarization layer. Meanwhile, the volume fraction of the polarization layer maintains the same in the two frameworks to minimize adverse effects on polarizations. Experimental and simulation results show that the transition layer is able to effectively reduce dielectric contrast that alleviates electric field distortion and increases two extra interlayer interfaces to prolong breakdown paths, leading to an improved E
b. In addition, Ni(OH)2 nanosheets could further hinder the breakdown path to suppress leakage current and prevent premature breakdown. As a result, the optimal nanocomposite with x= 60 achieves an energy density of 25.9 J cm−3 at 663.6 MV m−1, with an efficiency of 80%. This approach provides a promising design for advanced dielectric nanocomposites.
A robot in-place geometric model reconstruction method for additive manufacturing parts by fusing 3D scanner measuring data
Authors: Lei Guoqing , Wang Sicong , Li Jiajing , Lu Lei , Zhang Lei , Sun Lining
Published: January 2025

Geometric model reconstruction of additive manufacturing (AM) parts based on in-place measurement (IPM) is meaningful in realizing the robotic post-processing of AM parts. However, the low motion accuracy of the robot and the low efficiency of the IPM system restrict the development of the in-place model reconstruction. This paper presents a reconstruction method that integrates the 3D scanner and the robotic IPM system to improve the accuracy and efficiency of the model reconstruction. First, considering the measurement errors in the robotic IPM system, an error correction model is developed by measuring the calibration ball (CB) at the boundary of the measurement space. For each CB, a modified correction matrix (MCM) is constructed based on measurement data and geometric parameters of the CB to compensate for measurement errors. Second, a CB in the measurement space is measured, and the MCMs of each CB at the boundary are combined using the neural network model. Based on the measurement data of the CB, a geometric error correction model for the entire measurement space is developed, which corrects the spatial distribution of geometric errors in the robotic IPM system and enhances its accuracy within the measurement space. Finally, a local motion algorithm based on IPM data is proposed to calibrate the large volume of point cloud data from a 3D scanner. A high-precision model of AM parts is quickly reconstructed by fusing the few high-accuracy robotic IPM data with the large volume of low-accuracy point cloud data obtained by the 3D scanner. In order to verify the effectiveness of the method proposed in this paper, the measurement experiments on the CB are conducted. The results show that the model reconstruction accuracy can reach 0.06 mm compared with point cloud data obtained by the 3D scanner. The AM concave and convex parts are measured and the manufacturing geometric accuracy is analyzed by the proposed method. Compared to the digital model, the maximum deviation of the AM concave part is 1.3864 mm, and the maximum deviation of the AM convex part is 1.6802 mm.
A tool wear monitoring method driven by workpiece surface quality inversion and EfficientNet
Authors: Jiang Fei , Xiao Zejian , Yan Xiaohui , Wu Zhaoqian , Zhang Shaohui , Ullah Rizwan
Published: January 2025

Tool wear status monitoring plays an important role in the safety of machine and the efficiency of production. Due to the limitation of sensor installation and complex operation conditions, traditional machine vision methods are difficult to directly act on the tool itself to obtain corresponding wear status information. Meanwhile, the surface quality of the machined workpiece can provide indirect insights into the wear status of the tool to a significant degree. Therefore, an indirect tool wear status monitoring method is proposed in this paper by workpiece surface quality inversion and EfficientNet. Firstly, the surface texture data of workpiece are obtained in the form of image by an industrial camera, and the representative features that indirectly reflect tool wear status are further highlighted by using the weighted average image grayscale and the Laplacian operator. Secondly, to monitor tool wear effectively, we have optimized three key settings, width, model depth, and input image resolution, of the EfficientNet backbone network. This optimization boosts its ability to understand and generalize, ensuring it can handle various surface textures and extract crucial information accurately. This, in turn, enhances the accuracy of our tool wear monitoring system. Finally, the improved EfficientNet network is further utilized as a pre-trained network to achieve tool wear state monitoring. Utilizing the powerful representation ability of the pre-trained model and the surface texture features of workpiece, the model can accurately identify and judge the wear degree of the tool. The tool experiment results show that the proposed tool wear monitoring method has achieved remarkable results with recognition accuracy of 97.77%. While other popular methods such as VGG19, ResNet50, and ResNet152, whose training accuracies are 95.66%, 96.37%, and 91.27%, respectively. The comparative results highlight the excellent performance of the proposed method in recognition rate, training time and generalization performance.
Establishment and extension of a compact and robust binary feature descriptor for UAV image matching
Authors: Li Chenghong , Hu Chuan , Zhu Hongzhou , Tang Feifei , Zhao Lidu , Zhou Yin , Zhang Shuangcheng
Published: January 2025

Local feature description is a crucial challenge in unmanned aerial vehicle (UAV) images matching. Although scholars have explored a variety of methods for defining local feature descriptions, improving the matching accuracy of UAV images and reducing the memory consumption of descriptor remain worthwhile research issues. A compact and robust binary feature descriptor for UAV image matching is proposed. To achieve rotational invariance of the descriptor, a sampling pattern based on the region overlap error is employed to assign the dominant direction of the feature points. Additionally, a rotation invariant gradient computation method is proposed to reduce the dominant direction assignment errors. Then, the region around the feature point is divided into grids based on the region overlap error, and gradient orientation histogram and average intensity histogram are constructed. Finally, these histograms are binarized to generate a 30-byte binary descriptor. Results from the Oxford dataset, the Iguazu dataset, and a high-resolution UAV image dataset indicate that the proposed descriptor is compact and achieves the highest matching accuracy compared to nine commonly used feature descriptors, including scale-invariant feature transform, speeded up robust feature, binary robust invariant scalable keypoints, KAZE, oriented fast and rotated brief, fast retina keypoint, local intensity order pattern, boosted efficient binary local image descriptor, and triplet-based efficient binary local image descriptor. Notably, on the high-resolution UAV images with translational transformations, scale variations, salt-and-pepper noise, and Gaussian white noise, the accuracies of the proposed descriptor were 87.09%, 80.83%, 92.46%, and 87.42%, respectively. The improvements ranged from 6.95% to 53.20%, 9.32% to 55.90%, 10.39% to 44.29%, and 6.54% to 58.24%.
A real-time tumor position prediction based multi-dimensional respiratory motion compensation puncture method
Authors: Jiang Shan , Li Yuhua , Li Bowen , Yang Zhiyong , Zhou Zeyang
Published: January 2025

Objective:This study proposes a real-time tumor position prediction-based multi-dimensional respiratory motion compensation puncture method to accurately track real-time lung tumors and achieve precise needle puncture.Approach:A hybrid model framework integrating prediction and correlation models is developed to enable real-time tumor localization. A Long Short-Term Memory neural network with bidirectional and attention modules (Bi-LSTM-ATT) is employed for predicting external respiratory signals. Subsequently, a backpropagation neural network is constructed to correlate these signals with tumor positions. Tumor trajectory decomposition and the determination of an optimal puncture window based on multiple criteria ensure accurate needle puncture.Main results:When the delay time of Bi-LSTM-ATT model is 500 ms, its RMSE, MAE, and R2 are 0.0482 mm, 0.0414 mm, and 97.90% respectively. The correlation model locates lung tumors in 10 cases with a target registration error within 0.74 mm. The proposed puncture method achieves a puncture error ranging from 1.00 mm to 1.32 mm, with an average error of 1.2 mm.Significance:The proposed method is validated for its high accuracy and robustness, establishing it as a promising tool for percutaneous biopsy procedures within the lung.
The potential of photon-counting CT for the improved precision of lung nodule radiomics
Authors: McCabe Cindy , Abadi Ehsan , Zarei Mojtaba , Segars W Paul , Samei Ehsan
Published: January 2025

Objective. Lung nodule appearance may provide prognostic information, as the presence of spiculation increases the suspicion of a nodule being cancerous. Spiculations can be quantified using morphological radiomics features extracted from CT images. Radiomics features can be affected by the acquisition parameters and scanner technologies; thus, it is essential to identify imaging conditions that provide reliable measurements, particularly for emerging technologies like photon-counting CT (PCCT). This study aimed to systematically quantify the effect of imaging parameters on the radiomics measurements using a virtual imaging trial (VIT) platform, and further verify the findings with human clinical data. Approach. The VIT utilized nine virtual patients, each with three 6 mm nodules of varying spiculations. The virtual patients were run through a validated CT simulator (DukeSim) to acquire images at three dose levels (CTDIvol = 2.85, 5.69, and 11.38 mGy) with a clinical energy-integrating CT and a PCCT. The acquired projection images were reconstructed using multiple slice thicknesses, kernels, and matrix sizes. The reconstructed images were processed to extract morphological features using three segmentation methods. The features were clustered into three broad type categories. Features extracted from the acquired CT images were compared to their corresponding ground truth values, across all imaging conditions. Main results. Among all imaging conditions, slice thickness had the greatest effect on the radiomics measurements. When the thickest slices were used, the coefficient of variation increased by [1.19%–9.66%] in the energy integrating CT images, and [3.94%–24.43%] in the PCCT images. For both scanners, varying the kernel sharpness and dose affected the radiomics measurements insignificantly, while pixel size and segmentation method were observed to have stronger effects. Under varying imaging conditions, the trends and magnitude of radiomics features measurements were coherent with virtual trial results. Significance. The findings stress the importance of choosing optimal reconstruction settings for radiomics extraction to achieve precise feature quantifications.
Nuclear interaction correction based on dual-energy computed tomography in carbon-ion radiotherapy
Authors: Wakisaka Yushi , Yagi Masashi , Tominaga Yuki , Shimizu Shinichi , Nishio Teiji , Ogawa Kazuhiko
Published: January 2025

Objective. Accurate dose predictions are crucial to maximizing the benefits of carbon-ion therapy (CIT). Carbon beams incident on the human body cause nuclear interactions with tissues, resulting in changes in the constituent nuclides and leading to dose errors that are conventionally corrected using conventional single-energy computed tomography (SECT). Dual-energy computed tomography (DECT) has frequently been used for stopping power estimation in particle therapy and is well suited for correcting nuclear reactions because of its detailed body-tissue elemental information. This study proposes a correction method for the absolute dose in CIT that considers changes in nuclide composition resulting from nuclear reactions with body tissues, as a novel application of DECT. Approach. The change in dose associated with nuclear reactions is determined by correcting each integrated depth dose component of the carbon beam using a nuclear interaction correction factor. This factor is determined based on the stopping power, mass density, and nuclear interaction cross-section in body tissue. The stopping power and mass density were calculated using established methods, whereas the nuclear interaction cross-section was newly defined through a conversion equation derived from the effective atomic number. Main results. Nuclear interaction correction factors and corrected doses were determined for 85 body tissues with known compositions, comparing them with existing SECT-based methods. The root-mean-square errors of the SECT- and DECT-based nuclear interaction correction factors relative to theoretical values were 0.66% and 0.39%, respectively. Significance. This indicates a notable enhancement in the estimation accuracy with DECT. The dose calculations in uniform body tissues derived from SECT showed slight over-correction in adipose and bone tissues, whereas those based on DECT were almost consistent with theoretical values. Our proposed method demonstrates the potential of DECT for enhancing dose calculation accuracy in CIT, complementing its established role in stopping power estimation.
On the Ar I 419.8 nm/751.5 nm (3p5/2p5) line intensity ratio for electric field measurement in dielectric barrier discharge in argon at atmospheric pressure
Authors: Navrátil Zdeněk , Kusýn Lukáš , Prokop David , Hoder Tomáš
Published: January 2025

Ar I 419.8 nm/751.5 nm line intensity ratio is suggested as a measure of the electric field in atmospheric pressure dielectric barrier discharges (DBDs) in argon. Using the electron distribution function calculated from the Boltzmann equation, electron impact excitation cross sections, quenching coefficients and other atomic data, theoretical dependencies of several line intensity ratios constructed from Ar I 3p5 4p and 3p5 5p argon lines on the electric field were calculated. Among them, the intensity ratio of 5p line at 419.8 nm (1s

4

−
3

p5 in Paschen notation) to 4p line at 751.5 nm line (1s

4

−

2p5) was found to be sensitive in both the theory and the experiment. The suggested line ratio was applied to the study of an atmospheric pressure volume DBD in pure argon with sinusoidal voltage excitation. The spatiotemporal distribution of light emissions on 4p and 5p lines was measured using the time-correlated single photon counting technique with high temporal (180 ps) and spatial (25 µm) resolution. The light emission on 419.8 nm line indicated the high electric field region in the propagating cathode-directed streamer due to a high excitation energy (14.58 eV) and a short effective lifetime (150 ps) of the 3p5 level. Several measured and calculated electron impact excitation cross sections were examined to interpret the measured line intensity ratio. Using the calculation based on a combination of the calculated (Zatsarinny 2014) and the measured cross section (Boffard 2007) for 2p5 and 3p5 levels, the electric field strengths reaching 110–120 Td were measured in the streamer head. The assumptions and limitations of this approach, as well as its instrumentation requirements, are discussed.
Design rules to scale-up magnetic screens made of bulk superconductors and closed-loop coated conductors: modelling and experiments
Authors: Rotheudt N , Fagnard J-F , Hlasek T , Plechacek J , Vanderbemden P
Published: January 2025

Hybrid magnetic screens combining a disk-shaped high-temperature superconducting bulk with closed-loop coated conductors have been recently demonstrated to significantly overcome the screening properties of a single bulk. The purpose of the present work is to investigate how to scale up these hybrid screens, i.e. further increase the field attenuation and widen efficiently the screened region using more closed-loop coated conductors. First of all, an axisymmetric finite element model using the Gmsh and GetDP environments with the

H
−
ϕ

formulation is implemented and used to study the influence of physical and geometrical parameters of the screens. The results show that the low-field screening factor SF and the screened surface area are strongly dependent on the geometry while having large

J

c

materials is mandatory to maintain the screening properties up to high fields. An important design rule is that the spacing between the concentric loops should be sufficiently small, which we explain physically by analysing the different paths followed by the flux lines. Then, experiments are carried out in liquid nitrogen (77 K) with GdBa2Cu3O7 samples. Mapping the three components of the flux density above the screens subjected to an inhomogeneous applied field gives the following key results. First, the combination of the bulk with four loops spaced as recommended by the numerical model allows the screened surface area (SF

>
2

) to be multiplied by

∼

9

with respect to the bulk alone. Second, reducing the asymmetry of the practical structure by flipping over some of the loops is highly beneficial for improving the screening properties: the maximum SF at 5.7 mm the bulk is measured to be multiplied by 1.6 without any additional superconductor. Importantly, the design rules obtained from both the numerical model and the experiments can be further extended and applied to various geometries or sizes of hybrid superconducting screens.
The effect of heavy metals on the radiation shielding capabilities of borated polyethylene: a Geant4 study
Authors: Akhdar Hanan
Published: January 2025

Research has increasingly focused on polymers for radiation shielding in medical and industrial applications due to their beneficial properties. Polyethylene, a common polymer, is extensively used as a neutron shield in radiation-related environments, particularly in hospitals. Recently, borated polyethylene-created by combining polyethylene with 5% boron by weight-has been employed in hospital doors due to its exceptional durability across a wide temperature range and its effective neutron shielding capabilities. Hospital doors must protect against radiation leakage that could endanger patients and staff while also being lightweight, resistant to moisture and chemicals, sound-absorbent, and flexible during manufacturing. Borated polyethylene meets all these criteria, leading many manufacturers to produce hospital doors from borated high-density polyethylene (BHDPE). In this study, the shielding effectiveness of borated polyethylene, enhanced with 5% of heavy metals such as iron, bismuth, and tungsten, was theoretically analyzed using Geant4 against photons and neutrons with energies ranging from 10 keV to 20 MeV. The results indicated that iron-borated high-density polyethylene (Fe-BHDPE) offers the best neutron shielding, followed by tungsten-borated high-density polyethylene (W-BHDPE) and bismuth-borated high-density polyethylene (Bi-HDPE). For photon shielding, Bi-HDPE performed the best. The choice of metal and its proportion in radiation protection doors should be tailored to the specific type of radiation present in the facility, considering potential interactions, surrounding conditions, scattering effects, and any secondary particles that may be produced.
Potential of neutrino telescopes to detect quantum gravity-induced decoherence in the presence of dark fermions
Authors: Domi Alba , Eberl Thomas , Hellmann Dominik , Krieg Sara , Päs Heinrich
Published: January 2025

We assess the potential of neutrino telescopes to discover quantum-gravity-induced decoherence effects modeled in the open-quantum system framework and with arbitrary numbers of active and dark fermion generations, such as particle dark matter or sterile neutrinos. The expected damping of neutrino flavor oscillation probabilities as a function of energy and propagation length thus encodes information about quantum gravity effects and the fermion generation multiplicity in the dark sector. We employ a public Monte-Carlo dataset provided by the IceCube Collaboration to model the detector response and estimate the sensitivity of IceCube to oscillation effects in atmospheric neutrinos induced by the presented model.
Our findings confirm the potential of very-large-volume neutrino telescopes to test this class of models and indicate higher sensitivities for increasing numbers of dark fermions.
Star-crossed labours: checking consistency between current supernovae compilations
Authors: Matthewson W.L. , Shafieloo A.
Published: January 2025

We make use of model-independent statistical methods to assess the consistency of three
different supernova compilations: Union3, Pantheon+ and DES 5-year supernovae. We expand the
available model space of each, using Crossing Statistics, and test the compatibility of each
dataset, against the other two. This is done using (I) a Flat ΛCDM fitting to, and (II)
Iterative Smoothing from, one particular dataset, and determining the level of deformation by
required to fit the other two. This allows us to test the mutual consistency of the datasets both
within the standard model and in the case of some extended model, motivated by features present in
a particular dataset. We find that, in both these cases, the data are only consistent with the
point in the parameter space corresponding to zero deformation (of I and II), at around a
2σ level, with the DES compilation showing the largest disagreement. However, all three
datasets are still found to be consistent to within 1-2σ with each other.
Modified power law cosmology: theoretical scenarios and observational constraints*
Authors: Sharma L. K. , Parekh Suresh , Ray Saibal , Yadav Anil Kumar , Khlopov Maxim , Mehta Kalyani C.K.
Published: January 2025

This research paper examines a cosmological model in flat space-time via

gravity, where R and G are the Ricci scalar and Gauss-Bonnet invariant, respectively. Our model assumes that

is an exponential function of G combined with a linear combination of R. We scrutinize the observational limitations under a power law cosmology that relies on two parameters, the Hubble constant (

) and the deceleration parameter (q) utilizing the 57-point

data, 8-point BAO data, 1701-point Pantheon+ data, joint data of

+ Pantheon, and joint data of

+ BAO + Pantheon+. The outcomes for

and q are realistic within observational ranges. We also address energy conditions,

analysis, and cosmographical parameters such as jerk, lerk, and snap. Our estimate of

is remarkably consistent with various recent Planck Collaboration studies that utilize the ΛCDM model. According to our study, power law cosmology within the context of

gravity provides the most comprehensive explanation of the important aspects of cosmic evolution.
A method for diagnosing the implosion symmetry in inertial confinement fusion with wide-angle VISAR
Authors: Yuji Wu , Zanyang Guan , Qing Zhang , Longfei Jing , Kuan Ren , Juxi Liang , Xudan Chen , Yulong Li , Feng Wang
Published: January 2025

A method for diagnosing implosion symmetry in inertial confinement fusion (ICF) with wide-angle velocity interferometer system for any reflector (VISAR)was proposed in this study. The method considers the object-image relationship of the wide-angle VISAR, characteristics of the fringe pattern, and the symmetry theory; the fringe pattern must be continuous in space to apply this method. Hydrodynamic calculations showed that the radiation-temperature distribution on the surface of capsule was spatially continuous, indirectly proving the applicability of the method. The evolution of P2 asymmetry at different positions of the capsule was examined through an eight-beam laser indirect-drive experiment at a 10 kJ-level laser facility, proving the feasibility of the method. The application of wide-angle VISAR for the diagnosis of implosion symmetry in ICF was more accurate and intuitive and demonstrated high spatiotemporal resolution and wide detection range. This method can provide reference data for the micro-mechanism study of hydrodynamic instability and radiation-driven asymmetry, as well as support for optimizing the implosion compression process to achieve efficient and stable ignition.
Mechanical properties and microbial assessment of additively manufactured diamond and gyroid Ti-6Al-4V ELI scaffolds for interbody fusion cages applications
Authors: Kumar Mohit , Meena Vijay Kumar , Singh Suman
Published: January 2025

This study investigates the mechanical behaviour and microbial assessment of additively manufactured porous titanium scaffolds for interbody fusion cages applications. This study is meticulously designed to focus on both the mechanical and microbial assessments. Two types of cubic porous structure scaffolds were manufactured. The type 1 scaffold was designed with a diamond structure, featuring a pore size of 500 microns and 65% porosity. Similarly, the type 2 scaffold was designed with a gyroid structure, having a pore size of 500 microns and 65% porosity. Both the types of scaffolds were manufactured using direct selective laser sintering technique. Both the group of scaffolds tested for quasi static compression testing, fatigue compression testing, compression torsional testing and corrosion testing for mechanical properties evaluation. For microbial evaluation, bio burden tests, total organic carbon and total hydrocarbon tests were conducted on the both type of scaffolds. Static compression testing results reported that there is no significant effect on the compression strength properties. Diamond scaffolds had higher yield force value than gyroid scaffolds. Fatigue compression and compression - torsional results reported the higher endurance strength of diamond scaffolds over the gyroid scaffolds. There was no significant difference reported for corrosion behavior of both scaffolds. In the present study, both types of scaffolds demonstrated an almost negligible biological burden. The total organic carbon and hydrocarbons values reported were also under permissible limit as per ISO 19227.Results demonstrated several advantages such as higher endurance strength of diamond scaffolds over gyroid scaffolds, highly corrosion resistance and negligible bio burden limits.
Catalytic degradation of dyes using gold nanoparticles supported over chitosan coated cotton cloth composite
Authors: Awais  , Ullah Fahim , Khan Adnan , Khan Romana , Khan Sher Bahadar , Alzahrani Khalid A , Ali Nauman , Ul-Islam Mazhar , Chani Muhammad Tariq Saeed , Kamal Tahseen
Published: January 2025

The increasing environmental threat posed by various dye contaminants in wastewater necessitates the development of efficient catalytic systems for their removal. This research work investigates the synthesis of gold nanoparticles (Au NPs) on chitosan-coated cotton cloth (CH-CC) as a versatile catalyst for the reduction of hazardous dyes, specifically methylene blue (MB), rhodamine B (RB), and congo red (CR). The Au-CH-CC composite was prepared by treating CH-CC with HAuCl4 and reducing the formed ions using sodium borohydride. XRD, SEM, and EDX were adopted as characterization techniques which confirmed the successful formation of gold nanoparticles. The catalytic performance was evaluated via UV–visible spectrophotometry, revealing rapid dye reductions of 93%, 86%, and 98% for MB, RB, and CR in 12, 9, and 6 min, respectively. Kinetic analysis indicated pseudo-first-order kinetics by using the Au-CH-CC as catalyst, with respective rate constants of 0.18, 0.23, and 0.54 min−1. The recyclability of the catalyst was demonstrated by repeatedly recovering and reusing it in three successive cycles. The findings in this study reveal the potential of utilizing Au NPs on biomass-derived materials for environmentally friendly dye remediation, presenting a sustainable approach to mitigating dyes pollution from wastewater.
Hydrological drivers of flooding in Niamey (Niger): the role of the Sirba River
Authors: Tangam Idi Souley , Yonaba Roland , Ibrahim Boubacar , Adamou Mahaman Moustapha , Karambiri Harouna
Published: January 2025

In recent decades, floods have become a major global concern. In Niamey (Niger) in West Africa, flooding is primarily caused by the significant increase in surface runoff resulting from heavy rainfall occuring between July and September in the upstream river basins of the three major tributaries of the Middle Niger River (Sirba, Gorouol ad Dargol catchments). While the Sirba is empirically considered as the largest driver to flooding in Niamey, its contribution have not been precisely established. This study analyzes the influence of these tributaries on the Niger River discharges at Niamey during the rainy season, with a particular focus on the Sirba River basin. Daily annual maximum discharge (AMAX) data from 1990 to 2022 timeseries are used as inputs to various statistical analyses, including trend analyses, change point detection, concordance analysis and flood dependency assessment. The results reveal a significant change point in 2009 and increasing trends between the Sirba and Niger River stations. The flood propagation time delay varies from 1 to 4 days between the upstream river basins tributaries and Niamey station, with a strong concordance in peak discharges, particularly dominant with the Sirba River. The Dynamic Time Warping (DTW) and the Gumbel copula analyses highlighted the significant control of the Sirba River basin on flooding in Niamey, while also highlighting the important roles played by other tributaries. These findings are crucial for improving flood prevention and further refine urban flood management strategies in Niamey and other cities globally, affected by fluvial floods.