bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three-dimensional, time-dependent simulation of tapered EUV FELs with phase shifters
Authors: Kalitenko A M 
Published: March 2024

Abstract
In this article, we have developed and evaluated a method for obtaining extreme ultraviolet (EUV) radiation by amplifying the third harmonic of the free-electron laser (FEL) radiation using phase shifters and tapering. Simulations of self-amplified spontaneous emission (SASE) FELs and seeding schemes are presented. We have demonstrated that the combination of phase shifts and tapering results in a more efficient technique that reduces electron beam energy by half. The stability of the scheme in relation to phase shift errors has been analyzed, and the implementation of the method has been discussed. The proposed FEL design enables a decrease in facility energy and a reduction in the cost of both new and existing projects in the EUV band.
High performance Co3O4/Sn-ZnO nanocomposite photocatalyst for removal of methylene blue dye
Authors: Zena Zewdu Weldemichael , Andoshe Dinsefa Mensur , Tufa Lemma Teshome , Gemta Abebe Belay , Dejene Francis Birhanu 
Published: March 2024

Abstract
Methylene blue is a toxic, carcinogenic, and non-biodegradable synthetic dye discharged from factories and industries that causes severe harm to human health and environmental pollution. Therefore, in this work, Co3O4/Sn-ZnO nanocomposite was synthesized using a simple sol–gel method for efficient photocatalytic removal of methylene blue dye in an aqueous basic medium. The structural, optical, photoluminescence, morphological, and compositional properties were studied. The XRD result revealed that the crystal size increases as the full width at half maxima (FWHM) decreases when Co3O4 are coupled with Sn-ZnO. From UV-visible diffusive reflectance and photoluminescence spectroscopies, a narrowing of the band gap and a reduction of the charge carrier’s recombination rate were observed, respectively. The photocatalytic efficiency and degradation rate constant of 95.1% and 0.03251 min−1 were recorded for methylene blue dye upon the use of optimized catalyst dosage of 60 mg Co3O4/Sn-ZnO nanocomposite catalyst under an irradiation time of 100 min at room temperature for optimized pH value of 9 in an aqueous basic medium.
Modelling thermal energy transfer in a femtosecond pulsed laser ablation of metal using a coupled spring-mass oscillator
Authors: Sagisi Jenny Lou , Casero Marc Robert , Floro Andrian Lorenze , Salvador Mcgilvyn Cris , Dizon Rogelio , Garcia Wilson , Dasallas Lean 
Published: March 2024

Abstract
Femtosecond pulsed laser ablation (fs-PLA) is an interesting yet complicated field of study especially for undergraduate students entering the field. Hence, a bridging concept using classical and mechanical analog will be helpful. In this paper, we modelled the thermal energy transfer between electron and lattice system in a fs-PLA of metal described by two temperature model (TTM) using a coupled spring-mass oscillator. This was achieved by providing correspondence of TTM parameters to the coupled spring-mass oscillator, with temperature as position, electron thermal conductivity as coefficient of friction, electron-phonon coupling factor as spring term, electron/lattice heat capacity as the mass m
1/m
2 respectively, and laser source term as the driving force. The thermophysical properties considered are temperature dependent leading to position dependent parameters of coupled spring-mass oscillator. Results showed that the coupled spring-mass oscillator exhibit many behavior similar to the TTM. Additionally, maximum positions achieved by m
2 behave similarly with maximum lattice temperature after achieving certain threshold value. However, many features of TTM such as spatial dependence and crater formation are not observed in the coupled spring-mass oscillator. Despite its limitation, the coupled spring-mass oscillator model was able to represent many features of the thermal energy transfer of fs-PLA, and could be an easy and useful model in understanding fs-PLA.
Performance and reproducibility analysis of zinc sulfo-selenide and cuprous oxide based perovskite solar cell: A SCAPS study
Authors: Patil Santosh V , Bhargava Kshitij , Pharne Indrajit D 
Published: March 2024

Abstract
The combination of titanium dioxide (TiO2) as electron transport layer (ETL) and 2,2’,7,7’-Tetrakis [N,N-di(4-methoxyphenyl)amino]−9,9’-spirobifluorene (Spiro-OMeTAD) as hole transport layer (HTL) have been frequently used in solution-processed perovskite solar cells (PSCs). However, the high sintering temperature required during the deposition of TiO2 layer and expensive Spiro-OMeTAD are limiting its commercial applicability. In this context, the combination of zinc sulfo-selenide (ZnS0.5Se0.5) (as ETL) which can be spray coated and inexpensive cuprous oxide (Cu2O) (as HTL) can serve as an alternative. This report computationally explores and compares the utility of the combination of ZnS0.5Se0.5 and Cu2O against that of TiO2 and Spiro-OMeTAD in terms of performance and reproducibility of MAPbI3 based PSC. The performance of optimized baseline models is quantitatively compared in terms of the values of performance metrics. Also, their performance is compared with respect to variations in bulk/interfacial defect density using the electrical and impedance spectroscopy characterizations. Further, their reproducibility is compared under variable carrier mobility of absorber layer. The optimized champion and mean power conversion efficiency of ZnS0.5Se0.5/Cu2O based cell are 25.6% and 25.3% respectively with standard deviation of 0.73% which is quite impressive and realistic when compared to the existing literature. The results obtained are quantitatively explained based on correlation between the cumulative effect of transit and recombination resistances evaluated using Nyquist profiles. The report systematically addresses the importance of ETL and HTL combination towards improving the performance and reproducibility of solution-processed PSCs.
Surface modification of ZrC dispersion-strengthened W under low energy He plasma irradiation
Authors: Li Long , Liu Zhe , Chen Ze , Yin Chao , Mao Shifeng , Wu Xuebang , Ohno Noriyasu , Ye Minyou 
Published: March 2024

Abstract
ZrC dispersion-strengthened W exhibits high strength/ductility, low ductile-to-brittle transition temperature, and excellent thermal shock resistance, making it a promising candidate plasma-facing material for future fusion devices. In this study, surface modification of 0.5 wt.% ZrC dispersion-strengthened W (WZrC) under low energy and high fluence He plasma irradiation at high temperature was presented. Under the energy of 90 eV and fluence ranging from 6 × 1024 He·m−2–2 × 1026 He·m−2 He irradiation at 920 °C, a typical fuzz nanostructure appeared on the W matrix of WZrC. The thickness of fuzz layer is proportional to the square root of He irradiation fluence. The fuzz showed comparable thickness and structural features to pure W, indicating limited effects of the particle’s addition on resistance to high fluence He irradiation at high temperatures. Under continuous He injection, the fuzz would grow extending onto the particle area, making the particle obscured. Besides, the erosion behavior of particles under He plasma irradiation has been investigated, which is thought to be dominated by a sputtering process. Under the He influence of 6 × 1024 He·m−2, only nanopores were observed in the surface region. With fluence increasing to 5 × 1025 He·m−2, the surface became relatively uneven with larger holes. W aggregated in spots and distributed on the surface of the particle, which might be the result of subthreshold sputtering and deposition. When fluence further increased to 2 × 1026 He·m−2, the particles were eroded completely and covered by the extended fuzz, forming cavities. In addition, distinctive layered nanotendrils were observed above the cavities, which were characterized to consist of inner W-riched skeletons and outer Zr-riched layers. It indicates that the layered nanotendrils should be the result of fuzz extension combined with particle sputtering/deposition.
Determination of the mean energy of fast electron losses and anisotropies through thick-target emission on WEST
Authors: Barbui T. , Delgado-Aparicio L.F. , Stratton B. , Chellaï O. , Dumont R. , Hill K.W. , Pablant N.A. , Savoye-Peysson Y. ,   the WEST Team
Published: March 2024

Abstract
A new method to obtain the mean energy of fast electron losses in fusion plasmas using a versatile multi-energy hard x-ray (HXR) detector is presented. The method is based on measuring the thick-target emission of tungsten in the divertor region produced by fast electron losses interacting with the target and modeling the tungsten spectra by a Monte Carlo code which simulates the interaction between a beam of electrons and a solid target. The mean energy of the fast electron losses is determined through the comparison between the experimental and synthetic emission. The results show that fast electron losses during lower hybrid current drive discharges at WEST have a mean energy of 90–140 keV and represent only 2% of the total heat flux at the target. Additionally, anisotropic HXR emission has been detected for the first time at the WEST core and edge plasma, with opposite directions. It is due to the forward-peak emission of two distinctive populations of fast electrons: co-current fast electrons in the core and counter-current fast electron losses at the inner strike point. In view of future experiments like ITER where electron cyclotron current drive will generate a fast electron population, this technique could serve as a real-time monitor of fast electron losses and eventually feed an actuator on the current drive generation.
A review on transfer methods of two-dimensional materials
Authors: Cheliotis I , Zergioti I 
Published: March 2024

Abstract
Over the years, two-dimensional (2D) materials have attracted increasing technological interest due to their unique physical, electronic, and photonic properties, making them excellent candidates for applications in electronics, nanoelectronics, optoelectronics, sensors, and modern telecommunications. Unfortunately, their development often requires special conditions and strict protocols, making it challenging to integrate them directly into devices. Some of the requirements include high temperatures, precursors, and special catalytic substrates with specific lattice parameters. Consequently, methods have been developed to transfer these materials from the growth substrates onto target substrates. These transfer techniques aim to minimize intermediate steps and minimize defects introduced into the 2D material during the process. This review focuses on the transfer techniques directly from the development substrates of 2D materials, which play a crucial role in their utilization.
Spatially-resolved UV-C emission in epitaxial monolayer boron nitride
Authors: Rousseau A , Plo J , Valvin P , Cheng T S , Bradford J , James T S S , Wrigley J , Mellor C J , Beton P H , Novikov S V , Jacques V , Gil B , Cassabois G 
Published: March 2024

Abstract
We report hyperspectral imaging in the UV-C spectral domain in epitaxial monolayers of hexagonal boron nitride (hBN). Under quasi-resonant laser excitation, the UV-C emission of monolayer hBN consists in resonant Raman scattering and photoluminescence, which appear to be spatially uncorrelated. Systematic measurements as a function of the excitation energy bring evidence of a photoluminescence singlet at

∼

6.045

eV. The spatial variations of the photoluminescence energy are found to be around

∼

10

meV, revealing that the inhomogeneous broadening is lower than the average photoluminescence linewidth of

∼

25

meV, a value close to the radiative limit in monolayer hBN. Our methodology provides an accurate framework for assessing the opto-electronic properties of hBN in the prospect of scalable hBN-based devices fabricated by epitaxy.
Characterizing the stress relaxation behavior of unidirectional prepreg through a parallel fractional-order viscoelastic model
Authors: Liu Jun , Li Zhefu , Yue Guangquan , Liu Weiping , Cheng Zitong 
Published: March 2024

Abstract
In the hot-stamp molding and hot diaphragm forming processes of composites, pressure significantly influences shaping quality. This study establishes a novel parallel fractional-order viscoelastic (PFOV) model with two Scott-Blair elements, achieving remarkable accuracy (R2 = 0.99) with fewer parameters. Unlike traditional models, it incorporates the force history of prepreg, providing a more precise representation of its mechanical response. Comparative analysis against established models underscores its superior ability to capture intricate stress relaxation behaviors. Notably, the model’s reduced parameters enhance its physical interpretability, offering a significant advantage in simulating and predicting prepreg material compression behavior for diverse manufacturing processes.
On the microstructure, texture and electrochemical properties of severely deformed and artificially aged lightweight AA2050 Al–Cu–Li alloy
Authors: Jagadeesh C , H Shivananda Nayaka , S Prithivirajan , S Ramesh , Anne Gajanan 
Published: March 2024

Abstract
Lightweight 3rd generation Al–Cu–Li alloy AA2050 was severely deformed via Multi Axial Forging (MAF) at 170 °C followed by artificial aging at 150 °C. Effect of MAF and post MAF aging on microstructure and precipitation was investigated using transmission electron microscopy (TEM). Formation of deformation bands and large dislocation cells were evident on MAF processed samples. Post MAF peak aging resulted in the distribution of fine T1 precipitates in grain interiors with reduction in grain boundary precipitation. Bulk texture studies reveal the formation of strong Goss and S texture components upon MAF processing. Further, low temperature artificial aging doesn’t exhibit significant changes in texture characteristics, either in terms of texture intensities or texture components. Polarization studies showed that peak aged samples exhibited better corrosion resistance compared to un-aged samples. Overall, 12 pass MAF processed and peak aged samples showed higher corrosion resistance. Further, corrosion surface morphologies examination revealed the change in corrosion mechanisms with thermomechanical treatments. Improved corrosion resistance after MAF and peak aging widens the requirements in aerospace and aircraft applications for such engineering alloys.
Investigation of the effect of silica particles and silane coupling agent on silica-filled tire tread compounds
Authors: Um Gi-Yong , Kwon Taehoon , Lee Seong Hwan , Kim Seong Hye , Kim Min Yu , Choi Sejin , Yu Seunggun , Lee Jin Hong 
Published: March 2024

Abstract
Enhancing attributes such as abrasion resistance, wet grip, and rolling resistance significantly impacts the overall performance optimization in tire tread applications. These attributes are predominantly influenced by the dispersity of silica filler within tire tread compounds. Therefore, it becomes imperative to enhance silica dispersion by thoroughly investigating the impact of each constituent in the tire tread compound. This study aims to elucidate the effects of silica particle size and silane coupling agents on tire tread compound properties. The results demonstrate that larger specific surface area silica particles alongside 3-mercaptopropyltrimethoxysilane coupling agents effectively reduce filler–filler interactions and enhance silica dispersion within the tire tread compound. Consequently, these improvements contribute to the overall enhancement of tire tread compound performance. These findings offer valuable insights into advancing the reinforced performance of tire tread compounds through the synergistic utilization of each constituent.
3D printed grafts with gradient structures for organized vascular regeneration
Authors: Chen Yuewei , Zou Zhongfei , Fu Tao , Li Zhuang , Zhang Zhaojie , Zhu Meng , Gao Qing , Wu Shaofei , Fu Guosheng , He Yong , Fu Jiayin 
Published: March 2024

Abstract
Synthetic vascular grafts suitable for small-diameter arteries (<6 mm) are in great need. However, there are still no commercially available small-diameter vascular grafts (SDVGs) in clinical practice due to thrombosis and stenosis after in vivo implantation. When designing SDVGs, many studies emphasized reendothelization but ignored the importance of reconstruction of the smooth muscle layer (SML). To facilitate rapid SML regeneration, a high-resolution 3D printing method was used to create a novel bilayer SDVG with structures and mechanical properties mimicking natural arteries. Bioinspired by the collagen alignment of SML, the inner layer of the grafts had larger pore sizes and high porosity to accelerate the infiltration of cells and their circumferential alignment, which could facilitate SML reconstruction for compliance restoration and spontaneous endothelialization. The outer layer was designed to induce fibroblast recruitment by low porosity and minor pore size and provide SDVG with sufficient mechanical strength. One month after implantation, the arteries regenerated by 3D-printed grafts exhibited better pulsatility than electrospun grafts, with a compliance (8.9%) approaching that of natural arteries (11.36%) and significantly higher than that of electrospun ones (1.9%). The 3D-printed vascular demonstrated a three-layer structure more closely resembling natural arteries while electrospun grafts showed incomplete endothelium and immature SML. Our study shows the importance of SML reconstruction during vascular graft regeneration and provides an effective strategy to reconstruct blood vessels through 3D-printed structures rapidly.
Production of a double cermet coating to treatment of the turbine blades
Authors: Antar Riyadh S , Darweesh Salih Y , Ridha Fatima W 
Published: March 2024

Abstract
Turbine blades commonly encounter external defects, such as cracks and high porosity, while in operation. To mitigate these challenges, the method of thermal spraying by flame is utilized for the application of cermet materials, which comprise both metal and ceramics, onto the blades. This process involved incorporating manganese (Mn) into a chromium oxide (Cr2O3) base in varying proportions (3,6,9,12,15)%. Before this, the two blends underwent multiple preparatory stages, such as being combined in a micro-mill for two hours and subsequently dried at 80 °C for thirty minutes to eliminate any moisture in the lab. The coating bases were prepared from an out-of-service turbine bit and shaped into squares with a side length of 1 cm. The bases were then roughened and indented using a paint gun. The resulting models were sintered at a temperature of 1000 °C for two hours. A number of structural and physical tests were carried out for the painted models before and after thermal sintering. Scanning electron microscope tests revealed crystalline regularity and lattice consistency of the outer surface especially at 15%Mn. The observed results of actual density indicated a gradual increase in density with successive additions of manganese. However, there was a consistent decrease in real porosity and water absorption, resulting in lower values at 15%. The hardness and adhesion strength exhibited significant improvements, increasing by approximately 15%. Conversely, the addition of the stiffener led to a continuous decrease in thermal conductivity. Consequently, it was concluded that the ideal coating settings for achieving favorable results were a coating distance of 16cm, a coating angle of 90°, and thermal sintering at 1000 °C.
In-situ S/TEM DC biasing of p-GaN/AlGaN/GaN heterostructure for E-mode GaN HEMT devices
Authors: Mehta Abhas B , Zhu Xiangyu , Shichijo S , Kim M J 
Published: March 2024

Abstract
This work describes an in-situ electrical DC bias study of the E-mode GaN high electron mobility transistor (HEMT) device. A single transistor structure is biased and studied in real-time. The sample was made from an E-mode GaN HEMT device using Focused Ion Beam (FIB) milling and upright lift-off. The device lamella is subjected to forward gate bias to understand the device operation and physical changes under the bias. Active device area and micron level changes due to biasing were studied and identified as crucial factors affecting device reliability during continuous operation. Electric bias-induced physical changes are observed at the p-GaN layer and AlGaN interface on the p-GaN and GaN sides. Localized damage and defect formation, along with elemental diffusion, is observed. The formation of new defects over existing growth defects was seen in the p-GaN/AlGaN/GaN heterostructure. The study helped us identify the exact location of the failure, the region affected under bias, and the occurrence of physical changes due to the electrical bias on the in-situ device. Based on the study, gate breakdown failure and its location at the metal/p-GaN interface are understood to result from physical changes activated by electrical bias.
Dynamic mechanical characteristics of natural fiber hybrid composites, bio composites and nano composites –a review
Authors: Krishnasamy Prabu , G Rajamurugan , Belaadi Ahmed , R Sasikumar 
Published: March 2024

Abstract
Dynamic mechanical analysis (DMA) is a helpful technique in the evaluation of natural fiber composites (NFCs) for investigating the viscoelastic behavior concerning time, temperature, and frequency and calculating the phase shift. In this work, the DMA responses of biocomposites, nanocomposites, and hybrid natural fiber composites are compared, and the factors influencing the responses are evaluated. Fiber loading, filler addition, fiber treatment, fiber stacking, and matrix all affect how viscoelastic NFCs behave. Previous investigations have indicated that the ranges for the storage modulus are 2000 MPa to 5800 MPa, the loss modulus is 150 MPa to 450 MPa, and the tan δ is 0.2 to 0.6. The nanocomposite mesh reinforcement improves the interaction between all of its constituent parts, which raises the storage modulus. More specifically, because of the better component-to-component contact in the nanocomposite, the mesh size of the reinforcement improved the storage modulus. This review study has contributed to a broad understanding of the viscoelastic behavior of fiber composites utilized in automobile, aerospace, building science, housing, textile, and food packaging applications.
Probe with a metallic bowl termination to determine the electric material parameters from variable thicknesses
Authors: Bouesse Ghislain Fraidy , Moukanda Mbango Franck 
Published: March 2024

Abstract
This paper discusses a new approach to determining the material electric parameters (dielectric constant and dissipation factor) through a technique based on identical material variation thicknesses. The copper bowl controls the material thicknesses and allows quick and safe measurements to get to the electromagnetic material information. This approach assumes that the discontinuities generated at the probe and bowl are identical and removed through mathematical operations. The material under test (MUT) gap thickness doesn’t exceed one millimeter. Some formulations have been developed to determine the discontinuity condensers and both capacitors of each thickness. Two proposed developments have been given to extract the complex effective and relative permittivities. A mathematical formula has been proposed to ensure the transition from effective to intrinsic parameters, where the MUT thicknesses and the probe’s outer diameter of the inner conductor are considered. A de-embedding operation is necessary, and the method is suitable but not limited to low-k. The coaxial probe is flat terminated, and the experimental validation has been made in the frequency ranges 1 MHz—2.2 GHz for FR-4 HTG-175 and 1 MHz—0.8 GHz for Alumina 99.5%. All MUTs are

5.0
×
5.0

cm2, except their thicknesses. The suggested approach is straightforward in sample insertion, simple in data acquisition and implementation, and precise in the final parameters’ results.