bluuebunny/crossref_metadata_2025_split huggingface dataset:
Absolute atomic nitrogen density spatial mapping in three MHCD configurations
Authors: Remigy Alice , Menacer Belkacem , Kourtzanidis Konstantinos , Gazeli Odhisea , Gazeli Kristaq , Lombardi Guillaume , Lazzaroni Claudia 
Published: January 2024

Abstract
In this work, nanosecond two-photon absorption laser induced fluorescence (TALIF) is used to perform spatial mappings of the absolute density of nitrogen atoms generated in a micro-hollow cathode discharge (MHCD). The MHCD is operated in the normal regime, with a DC discharge current of 1.6 mA and the plasma is ignited in a 20% Ar/ 80% N2 gas mixture. A 1-inch diameter aluminum substrate, acting as a third electrode (second anode), is placed further away from the MHCD to emulate a deposition substrate. The spatial profile of the N atoms is measured in three MHCD configurations. First, we study a MHCD having the same pressure (50 mbar) on both sides of the anode/cathode electrodes and the N atoms simply diffuse in three dimensions from the MHCD. The recorded N atoms density profile in this case satisfies our expectations, i.e. the maximal density is found at the axis of the hole, close to the MHCD. However, when we introduce a pressure differential, thus creating a plasma jet, an unexpected N atoms distribution is measured with maximum densities away from the jet axis. This behavior cannot be simply explained by the TALIF measurements. Then, as a first simplified approach in this work, we turn our attention to the role of the gas flow pattern. Compressible gas flow simulations show a correlation between the jet width and the radial distribution of the N atoms at different axial distances from the gap. Finally, a DC positive voltage is applied to the third electrode (second anode), which ignites a micro cathode sustained discharge (MCSD). The presence of the pressure differential unveils two stable working regimes depending on the current repartition between the two anodes. The MCSD enables an homogenization of the density profile along the surface of the substrate, which is suitable for nitride deposition applications.
First principle studies on half-metallicity and pressure-induced half-metallic band gap in 3-d transition metal-based quaternary Heusler ScVCoZ (Z = Si, Ge, Sn, P, As, and Sb) alloys
Authors: Puthusseri Narayanan Namboodiri , Natesan Baskaran 
Published: January 2024

Abstract
In the present work, we predict a series of 3-d transition metals-based quaternary Heusler alloys (QHA) ScVCoZ (Z = Si, Ge, Sn, P, As, and Sb) (SVCZ), by employing density functional theory (DFT) calculations. We carried out extensive band structure (BS) and density of states (DOS) analysis to explain the half-metallic and magnetic behavior of the alloys. We found that SVCZ alloys stabilize in the F

4

̅

3m space group and exhibit a ferromagnetic (FM) ground state (GS). Among the QHAs, SVCZ (Z = Si, Ge, and Sb) exhibit intriguing half-metallic properties featuring 100% spin polarization at the Fermi level (EF). Additionally, the effect of pressure indicates a band gap opening in one of the spin channels for SCVZ (Z = P, and As), and the half-metallic characteristics are retained up to a compressive pressure, respectively of 65, and 79 GPa for SCVP and SCVAs. Elastic properties calculations suggest SVCZ alloys satisfy Born stability criteria and are mechanically stable. Among the predicted QHAs, SVCZ (Z = Si, Ge, and Sn) shows brittle nature, whereas SVCZ (Z = P, As, and Sb) are ductile.
Optical soliton solutions of fokas system and (2 + 1) Davey-Stewartson system by mapping method
Authors: Ahmed Naveed , Rani Mehwish , Dragomir Silvestru Sever , Bin Mohsin Bandar 
Published: January 2024

Abstract
In this article, a very effective technique called generalized auxiliary equation mapping method has been employed to investigate some very important nonlinear equations in optical fibers such as Fokas system and

(
2
+
1
)

Davey-Stewartson (DS) system. Under different situations, the obtained solutions exhibit various wave pattern like bright and dark soliton, kink soliton, periodic wave soliton and singular solitons. These solutions are novel and interesting and prove the efficiency of the method. The accuracy of the obtained results provides the competence of the method and ensures that it can be used for other mathematical models involved in optical fibers. Graphical simulation of some reported results has been discussed here to visualize and support the mathematical results in terms of 3D, 2D and contour plots.
Tunneling of rotational black string with nonlinear electromagnetic fields
Authors: Mirekhtiary F S , Abbasi A , Hosseini K , Tulucu F 
Published: January 2024

Abstract
In the background of anti-de Sitter spaces, a novel solution of a rotating black string (RBS) attributed to a nonlinear electromagnetic field has been derived. The authors have deciphered two metric functions which are called RBS1 and RBS2. The two real roots, the two metrics (RBS1 and RBS2), have been found based on Newton–Raphson method. Furthermore, the Hawking radiation of scalar particles has been studied by employing the Hamilton–Jacobi (HJ) method to calculate the Hawking temperature of RBS1 and RBS2.
Spike sorting in the presence of stimulation artifacts: a dynamical control systems approach
Authors: Shokri Mohammad , Gogliettino Alex R , Hottowy Paweł , Sher Alexander , Litke Alan M , Chichilnisky E J , Pequito Sérgio , Muratore Dante 
Published: January 2024

Abstract

Objective. Bi-directional electronic neural interfaces, capable of both electrical recording and stimulation, communicate with the nervous system to permit precise calibration of electrical inputs by capturing the evoked neural responses. However, one significant challenge is that stimulation artifacts often mask the actual neural signals. To address this issue, we introduce a novel approach that employs dynamical control systems to detect and decipher electrically evoked neural activity despite the presence of electrical artifacts. Approach. Our proposed method leverages the unique spatiotemporal patterns of neural activity and electrical artifacts to distinguish and identify individual neural spikes. We designed distinctive dynamical models for both the stimulation artifact and each neuron observed during spontaneous neural activity. We can estimate which neurons were active by analyzing the recorded voltage responses across multiple electrodes post-stimulation. This technique also allows us to exclude signals from electrodes heavily affected by stimulation artifacts, such as the stimulating electrode itself, yet still accurately differentiate between evoked spikes and electrical artifacts. Main results. We applied our method to high-density multi-electrode recordings from the primate retina in an ex vivo setup, using a grid of 512 electrodes. Through repeated electrical stimulations at varying amplitudes, we were able to construct activation curves for each neuron. The curves obtained with our method closely resembled those derived from manual spike sorting. Additionally, the stimulation thresholds we estimated strongly agreed with those determined through manual analysis, demonstrating high reliability (

R
2

=
0.951

for human 1 and

R
2

=
0.944

for human 2). Significance. Our method can effectively separate evoked neural spikes from stimulation artifacts by exploiting the distinct spatiotemporal propagation patterns captured by a dense, large-scale multi-electrode array. This technique holds promise for future applications in real-time closed-loop stimulation systems and for managing multi-channel stimulation strategies.
Creating equilibrium glassy states via random particle bonding
Authors: Ozawa Misaki , Barrat Jean-Louis , Kob Walter , Zamponi Francesco 
Published: January 2024

Abstract
Creating amorphous solid states by randomly bonding an ensemble of dense liquid monomers is a common procedure that is used to create a variety of materials, such as epoxy resins, colloidal gels, and vitrimers. However, the properties of the resulting solid do a priori strongly depend on the preparation history. This can lead to substantial aging of the material; for example, properties such as mechanical moduli and transport coefficients rely on the time elapsed since solidification, which can lead to a slow degradation of the material in technological applications. It is therefore important to understand under which conditions random monomer bonding can lead to stable solid states, that is, long-lived metastable states whose properties do not change over time. This work presents a theoretical and computational analysis of this problem and introduces a random bonding procedure that ensures the proper equilibration of the resulting amorphous states. Our procedure also provides a new route to investigate the fundamental properties of glassy energy landscapes by producing translationally invariant ultrastable glassy states in simple particle models.
Mechanical switches integrated sandwich triboelectric nanogenerator with high instantaneous output power
Authors: Wu Han , Liao Ruijin , Wang Jiyu 
Published: January 2024

Abstract
Triboelectric nanogenerator (TENG) has emerged as a promising energy harvester that converts random mechanical energy in the environment into electricity to enable self-powered system construction. However, the conventional TENG exhibits a large internal resistance resulting in a low output power across external loads for practical application. In this work, the travel mechanical switches were integrated into the TENG to boost output power, where the switches were turned on and off by the periodic motion between the triboelectric layers. Moreover, the triboelectric layers of TENG were developed as contact separation sandwich structures to work with mechanical switches, allowing the device to release the co-accumulated charges from the dual triboelectric layer to yield giant instantaneous discharge. Compared to a conventional TENG, the device offers ~2.8 times more transfer charge in one cycle and ~106 times more instantaneous power at an external load of 500 Ω, which renders the internal impedance match almost negligible. As a result, the high-power source demonstrates the ability to illuminate the commercial lamps in parallel (total power: 50 W). Such a unique TENG with high output power for low resistance load could greatly enrich the practical application fields of self-powered systems.
The flame retardancy and mechanical properties of waste polyester fabric/hemp stalk composites modified with piperazine pyrophosphate and ammonium polyphosphate
Authors: Li F , Shi Y R , Liu J T , Cui Z , Lu Y Z , Niu M , Xue B X 
Published: January 2024

Abstract
The piperazine pyrophosphate (PAPP) and ammonium polyphosphate (APP) were employed to enhance the flame retardancy of waste polyester/hemp stalk composites. And the impact of PAPP/APP flame retardants on the flame retardancy and mechanical properties of waste polyester/hemp stalk was investigated. The results indicated that the PAPP/APP combination offered superior flame retardancy, with minimal impact on the composites’ bending property. Notably, when the total addition of PAPP/APP was 25%, with a mass ratio of 1 to 1, the limiting oxygen index (LOI) value of the PAPP/APP/waste polyester/hemp stalk composite material increased significantly from 18.8% to 27.1%, achieving the flame retardant level. Correspondingly, the vertical combustion level attained V-0 level, and the charring rate at 600°C escalated from the initial 25.8% to 32.5%. Remarkably, both the bending strength and modulus of PAPP/APP/waste polyester/hemp stalk composites remained stable.
Hybrid directed energy deposition process coupled with plastic deformation
Authors: Yang J X , Wang R , Hu X Q , Wu M Y , Rao H , Bi Y J 
Published: January 2024

Abstract
Laser directed energy deposition (LDED) process has unique advantage in rapid forming of large-sized metal components, gradient material/structural components, or repairing/remanufacturing worn parts. However, the high residual stress and strong anisotropy in mechanical properties of the as-deposit components limit the application of LDED technology in the manufacturing of key structural components. To overcome these problems, various hybrid additive manufacturing (HAM) technologies have been developed, such as plastic deformation, ultrasonic or magnetic field assisted LDED processes to improve the quality and the mechanical properties, where these coupled processes are carried out either simultaneously or cyclically with the LDED process. The hybrid additive manufacturing, while retaining the advantages of individual forming process, avoids the mutual interference between each process and reducing the adverse effects generated if used separately. Hybrid additive manufacturing processes fundamentally change the underlying physical mechanisms of molten pool dynamics, microstructural evolution, temperature and thermal stress gradient in additive manufacturing, thereby optimizing the microstructure and performance of the manufactured components. In this paper, the key technical features of the hybrid additive manufacturing process coupled with plastic deformation were described in details, and the resulting differences in microstructure, residual stress, and mechanical properties of the prepared samples were systematically analyzed. The developing trend of hybrid additive manufacturing processes in coupling mechanisms, parameter optimization, and equipment have been discussed.
Quantitative study of high-frequency fatigue hole-edge stresses in nickel-based single-crystal superalloy
Authors: Li Leyu , Li Zheng , Liu Jiabin , Zhang Jingang , Deng Zhiwei , Li Quanwei , Liu Xinling 
Published: January 2024

Abstract
In this paper, the influence of air film holes on the stress distribution of nickel-based single-crystal superalloy blades is investigated, a simulated test piece is designed for the analysis and test of the stress distribution of air film holes, and a method of quantitative inverse inference of the stress at the edge of the air film holes is proposed. Finite element simulation of high circumferential vibration fatigue of the simulated test piece was carried out by ANSYS to obtain the gradient of stress distribution at the hole edge. The EBSD technique was used to measure the dimensions of the plastic zone in the region near the fracture, and the quantitative fatigue stresses were extrapolated using a crack tip plastic zone model with Tresca yield criterion. The compressive stress exerted by the femtosecond laser perforation method on the air film aperture wall was detected by the nanoindentation technique, and the residual stress was analysed using the S. Suresh computational model. The results of this study show that based solely on finite element simulation, it is not possible to completely simulate the effect of residual stresses caused by machining on fatigue fracture, which in turn leads to a lack of conformity between the results of finite element simulation and the results of the inverse plastic zone size extrapolation; however, the stress magnitude at the edge of the hole can be well computed by combining the stress concentration coefficients from finite element simulation with the stresses from the inverse plastic zone size extrapolation after taking into account the residual stresses from machining. The quantitative analysis results of this method have an error within 1.3 times the dispersion band compared to the test data.
Research on the construction and properties of waste cotton cellulose/carbon dots composite antibacterial hydrogel
Authors: Liu J , Liu Y , Zhang C Y , Shao Z Y , Niu M , Xue B X 
Published: January 2024

Abstract
The recycling and utilization of waste cotton fabrics is of great significance to implement green pollution reduction and carbon reduction. In order to realize the high value-added utilization of waste cotton cellulose (WCC) by introducing new carbon dots (CDs), WCC/CDs composite hydrogel with good antibacterial effect were prepared for the application in the field of antibacterial dressings. WCC/CDs composite hydrogel formed by doping different contents of carbon dots (CDs) with WCC hydrogel as raw material and epichlorohydrin (EPI) as crosslinking agent. The structure was characterized by X-ray diffraction (XRD) and infrared spectrum analysis, the antibacterial properties and swelling properties of WCC/CDs composite hydrogel were tested. The results show that the addition of CDs promoted the gelation of WCC hydrogel, enhanced its structure stability and endowed it with antibacterial properties. WCC/CDs composite hydrogel with 10wt% CDs was more stable, and its modulus reached 91 KPa. Compared with WCC hydrogel the swelling performance of WCC/CDs composite hydrogel was improved, and the swelling rate was 16.81 g·g-1. By destroying the cellular structure of bacteria and promoting the production of ROS, the inhibition rate of E. coil and S. aureus was more than 99%.
Stability of the microstructure and properties of Ti2AlNb alloys under thermal exposure conditions
Authors: Wei Z W , Ma L , You L , Liu C K 
Published: January 2024

Abstract
In this paper, the microstructure and property stability of Ti2AlNb alloy specimens treated by thermal exposure at 800°C for 0~12h were investigated using universal tensile tester, X-ray diffractometer, scanning electron microscope, electron backscattering diffraction, and in-situ tensile scanning electron microscope. The results show that with the extension of thermal exposure time, the tensile strength and yield strength of the alloy slightly increased, the B2-phase of the alloy decreased while the O-phase increased, and the content of the α2-phase also slightly decreased. It has been found that the properties changes are related to the changes of microstructure. The tensile cracks expanded along the grain boundaries between the O-phase and B2-phase as well as along the O-phase grain boundaries. The slight changes in microstructure and properties indicate that the Ti2AlNb alloy is stable and reliable for short-term service at 800 °C.
Effects of different treatment processes on microstructure and tensile fracture behaviour of selected laser melting TC17 titanium alloy
Authors: Jiang T , Dong X Y , Chen H H , Sun B B 
Published: January 2024

Abstract
It is essential to study the tensile fracture mechanism of additively manufactured materials and develop the effective process treatment techniques to improve their fracture resistance. In this paper, the effects of different treatment processes on the microstructure and tensile fracture properties of TC17 titanium alloy melted by laser selective zone melting were investigated. The static tensile fracture morphological characteristics were observed by combining SEM and EDS. The metallographic microstructure after chemical corrosion was observed optically. And the tensile fracture morphology of the three states of TC17 titanium alloy samples at room temperature conditions was investigated. The results show that the metallographic matrix microstructure of TC17 titanium alloy after HT, HIP and HIP-HT treatments was a bimodal structure with α+β phases, i.e., β phase was in the form of a net basket, and α phase was in the form of a coarse bar. The grain sizes of the samples treated by different processes were different, but the difference in grain size of the HT-treated tissues was small, and the difference in grain size of the HIP-HT-treated tissues was large. And the coarse α-phase segregation could be seen at the edge of the samples. The 3D-printed materials had complex changes in anisotropic properties affected by the printing structure and tissue. The printed tissues were brittle and had high internal stresses. These problems were partly improved at high temperatures, but they still existed. The HIP-HT-treated materials had a large α+β-phase bimodal structure. The HT-treated material had coarse grains and precipitation phases, poor room temperature plasticity, and improved high temperature plasticity. After HT treatment, the original printing microstructure changed, the strength and plasticity were significantly improved, but the macroscopic printing structure still had a slight influence on the fracture morphology. When HIP treatment temperature was higher, the influence of macroscopic printing structure basically disappeared, but the grain and microstructure grew up, and the strength and plasticity were slightly lower than that of the HT treatment. HIP process basically eliminated the unfused defects of the three-dimensional morphology, and the local weak bonding zone formed.
Fault Analysis of 35kV Outdoor Vacuum Circuit Breaker Pillar Porcelain Sleeve
Authors: Wu Jinhua , Zou Weiwei , Zhang Zhaoyu , Zhou Yanke 
Published: January 2024

Abstract
In order to further clarify the failure mechanism of the pillar porcelain insulator, the field inspection, the microscopic morphology analysis and material analysis of the ceramic shell of the pillar under a 35kV outdoor vacuum circuit breaker were carried out. The results show that the direct cause of the failure is the discharge between the high voltage conductor inside the porcelain sleeve and the weak part of the porcelain sleeve, and the high temperature arc leads to the bursting of the porcelain sleeve. The indirect cause of the failure is the loose porcelain of the porcelain sleeve, the existence of internal layering, uneven composition and micro-pores and other macro and micro defects, and the original defects of the inner surface of the porcelain sleeve, such as local unglazed and poor quality of the porcelain sleeve manufacturing process. In the long-term outdoor operation, the external moisture and gas penetrate into the porcelain sleeve, which leads to the deterioration of the insulation performance of the porcelain sleeve, and eventually leads to failure.
Failure analysis of frequent fracture accident of torsional shear type high strength bolts for steel structure of a thermoelectric 2×350MW unit project in Northwest China
Authors: Jiang Fei , Wu Jinhua , Lv Yanting , Zhang Suhui , Zhang Zhaoyu , Zhou Yanke 
Published: January 2024

Abstract
In this paper, the frequent breakage of high-strength torsional shear bolts used in steel structure of a 2×350MW thermoelectric unit in northwest China is taken as an example. By means of macro and micro fracture analysis, physical and chemical inspection, the causes of frequent breakage of high-strength bolts are analyzed and the improvement measures are put forward. The results show that the failure of the 20MnTiB steel high-strength bolt after assembly is hydrogen embrittlement fracture, and the main cause of the failure is the presence of zinc layer on the bolt surface and a large number of zinc microholes on the shallow surface.
Techno-economic Analysis of Optimal Grid-Connected Renewable Electricity and Hydrogen-to-Power Dispatch
Authors: Shaikh Raheel A. , Kumar Yogesh Pipada Sunil , Islam Shah Mohammad Mominul , Abbott Derek 
Published: January 2024

Abstract
One of the significant challenges in renewable integration is balancing supply and demand. The variability in generation and demand forces the grid to experience significant market price volatility. Moreover, electricity curtailment is adhered to during low-demand periods. Hydrogen Energy storage systems (HESS) can provide power dispatch flexibility and facilitate the reduction in curtailment. Unlike other storage systems such as batteries, the energy and power capacities for HESS design can be decoupled, resulting in a long-duration storage solution. In our paper, we perform electricity dispatch optimization from renewable sources such as solar and wind to the electricity market, where hydrogen is optimally produced using electrolysis, stored during low electricity prices, and converted to electricity using fuel cells to support the grid. The capital cost optimization suggests high profits for investors leveraging market price volatility even with low HESS round-trip efficiency and high upfront costs.