bluuebunny/crossref_metadata_2025_split huggingface dataset:
In-situ and ex-situ characterizations of PVT-grown 4H-SiC single crystals
Authors: Shao Qinqin , Shen Ruohan , Tian He , Pi Xiaodong , Yang Deren , Wang Rong 
Published: August 2024

Abstract
4H silicon carbide (4H-SiC) is one of the most promising candidates in high-power and high-frequency devices, owing to its excellent properties such as wide bandgap, high electron mobility, high electric breakdown field and high thermal conductivity. The physical-vapor-transport (PVT) approach has been broadly adopted to grow 4H-SiC single-crystal boules. Because of the high-temperature growth of 4H-SiC single-crystal boules, the PVT system is a ‘black-box’ system, which decreases the yield and thus increases the cost of 4H-SiC single-crystals. Although advanced modern characterization tools, e.g. atomic force microscopy, x-ray topography, x-ray diffraction and Raman scattering spectroscopy, can provide deep insight into the structural and defect properties of 4H-SiC boules, it is rather limited to gain in-situ information of the growth process by these ex-situ methods. Therefore, the in-situ visualization on the evolution of structural morphologies and defects conducted by x-ray computed tomography (xCT) is of great importance for further development. In this topical review, the application of the xCT technology on the in-situ visualization of the evolution of the growth front, growth rate, defects, and the mass transport of the source material of 4H-SiC are reviewed. The ex-situ characterization of 4H-SiC single-crystal boules are also briefly introduced. This topical review provides insight into the growth process, structural morphology, and defect evolution of PVT-grown 4H-SiC single-crystal boules.
Large-area gapped edge states in a valley photonic crystal heterostructure
Authors: Li Meize , Liu Yahong , Zhou Xin , Du Lianlian , Li Peng , Tao Liyun , Song Kun , Li Zhenfei , Zhao Xiaopeng 
Published: August 2024

Abstract
Recent works exploiting photonic valley Hall effect show that large-area topological states can be realized by inserting gapless photonic crystal structures into topological interfaces, thus effectively introducing mode width degree of freedom. However, the previously reported works focus on gapless edge states. It is rare to investigate gapped edge states, especially large-area gapped edge states. In this paper, large-area gapped edge states in a valley photonic crystal heterostructure are achieved and experimentally proved. Compared with large-area gapless topological states, the present gapped edge states are more localized, which provides a more effective way to manipulate electromagnetic waves. We implement a topological energy concentrator and topological resonator cavity based on the large-area topological transmission with the gapped edge states. It is expected that our results broaden photonic systems, which can be used in topological lasing, field enhancement, and high-capacity energy transport.
Photochromic webbing structures for monitoring UV-induced mechanical strength degradation
Authors: Kazemipour Sina , John Ohanian III Osgar , Porfiri Maurizio , Zhang Peng 
Published: August 2024

Abstract
Webbing structures are critical load-bearing components in a wide array of applications from structural restraint layers in inflatable space habitats to safety harness belts used by construction workers. In the field, webbings are subjected to ultraviolet (UV) irradiation from sunlight, leading to material degradation and a loss of mechanical strength. To date, health monitoring of webbings has relied on empirically correlating UV-induced strength loss with variations in their inherent color, which often yields inconsistent and imprecise results. To fill this gap, we propose a novel class of photochromic webbing structures that afford noninvasive monitoring of UV-induced degradation of their mechanical strength. The webbings’ sensing capabilities are achieved by integrating a class of photochromic yarns, fabricated through a pressurized coating process. Under continuous UV irradiation, the proposed photochromic webbings exhibit a substantial color change, demonstrating a sensing lifetime equivalent to several months in field conditions. We establish a strong correlation between the webbings’ photochromic response and their strength loss, supporting the feasibility of the proposed webbings in monitoring their mechanical integrity. To elucidate the sensing mechanism, we propose a physics-based mathematical model that describes the underlying photochemical reactions. Through an asymptotic analysis, we demonstrate that the model accurately predicts the webbing’s long-term photochromic responses under extended UV irradiation. The proposed photochromic webbing structures and the predictive mathematical model could enhance the safety and integrity of webbing-based engineering systems.
Multi-objective topology optimization of macro structure and microtubule network structure for self-healing material
Authors: Tan Jianbin , Li Peng , Cheng Wentao , Zhang Changyou , Fan Baijia , Wang Shenbiao , Zhan Jinqing 
Published: August 2024

Abstract
Self-healing materials possess the capability to promptly repair minor damages occurring during service, thereby effectively preventing safety accidents. This paper investigates a multi-objective topology optimization method for the macro structure and microtubule network of self-healing materials around pure epoxy resin materials, aiming to enhance the damage healing capability of the microtubule network while meeting the mechanical performance requirements of the macro structure. By introducing the design variables of macro structure and microtubule network, the corresponding topological description functions are established respectively. And study applies logical operations and post-processing techniques to generate an embedded microtubule network structure description. The objective functions include the flexibility of the macro structure, the along-travel head loss, and the total length of the microtubule network, with material volume serving as a constraint. In order to determine the head loss of the three-dimensional microtubule network structure, a Hardy-Cross method based on flow initialization and loop search is proposed. Multi-objective topology optimization is designed based on moving morphable components algorithm, enumeration method and Pareto principle. Develop iterative termination conditions by assessing the disparity between Pareto solution sets in each generation, thereby ensuring algorithm convergence. The numerical example of the Messerschmitt–Bölkow–Blohm (MBB) beamyields a flexibility of 0.059 without a carrier and 0.0728 with a carrier the macrostructural flexibility without a carrier is 81.0% compared to with a carrier, and the macrostructural profiles and the overall flexibility of the MBB beams with/without a carrier are close to each other. This method serves as a reference for optimizing large-scale self-healing structures.
Structural and phase transformations in Fe-Pd-Ag layered thin films by grain boundary diffusion
Authors: Gulyás Szilvia , Katona Gábor L 
Published: August 2024

Abstract
The influence of the stacking order and of an additional Ag layer on the formation of ordered phases in thin (< 50 nm) layered Fe/Pd and Fe/Ag/Pd films was investigated at 460 °C. The samples were prepared by magnetron sputtering at room temperature on Si/SiO2 substrate and were post-annealed in vacuum. Composition depth profiling and x-ray diffraction were used to characterize the processes. It has been shown, that the stacking order strongly influences the formation of ordered phases both in Fe/Pd bilayered and Fe/Ag/Pd trilayered films. In bilayered Fe/Pd films for both stacking orders the FePd3 phase appeared and it also showed L12 ordering for one stacking order. Addition of Ag layer between the Fe and Pd layers found to promote the formation of FePd phase which showed L10 ordering or A1 disordered structure depending on stacking order. Based on the analysis of the chemical depth profiles and XRD patterns the transformations were interpreted by grainboundary diffusion mechanisms including grainboundary diffusion induced grainboundary migration and solid state reaction.
Early and late observational tension: dark energy parametrizations in horava-lifshitz gravity via baryon acoustic oscillations
Authors: Chaudhary Himanshu , Debnath Ujjal , Rahaman Farook , Mustafa G , Atamurotov Farruh 
Published: August 2024

Abstract
We investigate late-time cosmic expansion within the Horava Lifshitz gravity framework using Barboza Alcaniz (BA) and Jassal Bagla Padmanabhan Parametrizations (JBP) as alternatives to general relativity. Anisotropic scaling is introduced at ultraviolet scales. Our aim is to constrain each cosmological parameter using the crucial Baryon Acoustic Oscillation (BAO) scale, specifically the sound horizon (r

d
), by treating (r

d
) as a free parameter. We employ 30 Hubble parameter measurements (H(z)) from cosmic chronometers, along with Type Ia Supernovae, Gamma-Ray Bursts, Quasars, and 24 uncorrelated BAO measurements spanning z = 0.106 to z = 2.33. The analysis includes the 2022 Hubble constant measurement by Riess (R22) as an additional prior and aims to minimize errors by simulating random correlations in the covariance matrix. In both the BA and JBP frameworks, utilizing the full dataset yields sound horizon results of r

d
= 146.5399 ± 2.4519 Mpc and r

d
= 146.4533 ± 2.4519 Mpc, respectively. When incorporating R22 results, the sound horizon values become r

d
= 143.4721 ± 1.8324 Mpc and r

d
= 142.9826 ± 1.9084 Mpc. These findings reveal a discrepancy between early and late observations, echoing the H
0 tension. Notably, excluding R22 aligns r

d
with Planck and SDSS results. Model predictions are evaluated against Hubble Measurements and the ΛCDM Paradigm. A comparative study between BA and JBP Models using the Cosmography test shows both models fitting seamlessly within the phantom region. Statistical analysis suggests neither model can be ruled out based on the latest observational measurements.
Structural evolution of zinc doped cadmium telluride at high pressure and high temperature
Authors: Aparajita A N Arpita , Shukla Balmukund , Vijayakumar P , Kumar N R Sanjay , Ganesamoorthy S , Srihari V , Shekar N V Chandra 
Published: August 2024

Abstract
Cd0.9Zn0.1Te (CZT) has gained a lot of traction with its application in the field of radiation detectors. In this study, CZT has been investigated using in situ x-ray diffraction(XRD) at high pressures up to 22 GPa, and both high pressure and high temperature (HP HT) up to 5 GPa and 400 °C. CZT adopts zinc blende phase at ambient condition. We have observed the previously unreported cinnabar type phase in CZT at high pressure. Cinnabar type phase nucleated at 1.8 GPa because of the motion of Te atoms in the ab-plane of zinc blende CZT and coexisted with the parent phase. The onset of transition to rocksalt phase took place at 4.7 GPa with successive atomic displacement along a and c direction of the cinnabar type unit cell. The parent phase disappeared at 6.3 GPa, but cinnabar type phase as a distorted form of rocksalt phase coexisted with the rocksalt phase due to the comparable energy for both the structures. The mechanism of transitions to cinnabar type and rocksalt phase is of quasi-reconstructive nature. Further, the rocksalt phase underwent a displacive transition to an orthorhombic (Cmcm) phase at 10.7 GPa which is accompanied by expansion along one axis and compression along the other two axes. In the reverse pressure cycle, the transitions were reversible and sluggish in nature. In the in situ high pressure and high temperature XRD studies, distinct structural hysteresis was observed and the transition to rocksalt phase was irreversible. At ambient pressure, the zinc blende structure remained stable up to 400 °C. The thermal expansion coefficient of the zinc blende phase and the high pressure rocksalt phase were estimated to be 23(1) × 10−6/°C and 10.2(1) × 10−6/°C respectively.
Reconsideration of Wigner’s Supermultiplet Symmetry
Authors: Draayer Jerry P , Pan Feng , Dang Phong 
Published: August 2024

AbstractThe objective of this ‘Reconsideration of Wigner’s Supermultiplet Symmetry’, which Wigner advanced in 1937, and for which he was awarded the Nobel Prize in Nuclear Physics in 1963, is first to take a cursory look back at physics-related issues and competing priorities of that (WW-I & WW-II) dominated period, since in retrospect it seems Wigner’s Supermultiplet Symmetry (respectfully denoted WSS in all that follows) is an example of a theory that seems to have been proffered ‘ahead of its time’. Secondly, to reflect on what has transpired over the follow-on decades of the Cold-War Era (1950s through 1980s); specifically, regarding the role that the WSS played (or did not play) across that period. And thirdly, to review the transformational changes of the late 1980s into the 1990s, and thereafter that came with the availability of high-performance supercomputing facilities and advanced algorithmic developments that opened new doors for the testing of more sophisticated models of nuclear structure which ultimately, at the onset of the 21st Century, led to the development of what was christened the ‘no-core’ shell-model (NCSM) by its developers. Shortly afterward, this was followed by the release of a symmetry-adapted version (SA-NCSM) of the NCSM, both of which have been advanced further over the ensuing years for carrying out ever more realistic, forefrontab initioshell-model calculations. Most recently, based upon the lessons learned through the creation, deployment, and updating of the SA-NCSM, it seems it should now be possible to address any and all of the remaining issues that stand in the way of establishing a truly 21st Century Shell-Model Theory that meets most, and perhaps even all, of the expectations that Wigner seemed to envision in his 1937 proffering of the WSS concept.
Impact of segregation and integration on infection dynamics: analysis of a Cholera model in a two-population system
Authors: El Deeb Omar , Matar Antoine 
Published: August 2024

Abstract
We present a novel dynamic model designed to depict Cholera outbreaks within a two-population framework featuring two environmental reservoirs. The model is designed to emulate the impact of segregation or integration between two populations on the transmission of the disease and infections throughout the entire community, both with and without non-medicinal interventions. This is achieved by allowing infectious individuals to interact with the reservoir of the alternate population at different levels of suppression, in addition to their regular interaction with their own reservoir. We find out that increased suppression of cross community interaction reduces the number of infections in the overall population as well as in the population with less contamination and contact. Additionally, we predict significant delays in the occurrence of peak infections, affording public health authorities crucial time for intervention. Lowering cross-immunity interactions also leads to a decrease in bacterial concentrations in environmental reservoirs. Finally, we demonstrate that non-medicinal interventions, including sanitation and water purification, would significantly reduce and delay infections, providing a valuable time frame for implementing additional medicinal measures.
Phase-resolving the Absorption Signatures of Water and Carbon Monoxide in the Atmosphere of the Ultra-hot Jupiter WASP-121b with GEMINI-S/IGRINS
Authors: Wardenier Joost P. , Parmentier Vivien , Line Michael R. , Weiner Mansfield Megan , Tan Xianyu , Tsai Shang-Min , Bean Jacob L. , Birkby Jayne L. , Brogi Matteo , Désert Jean-Michel , Gandhi Siddharth , Lee Elspeth K. H. , Levens Colette I. , Pino Lorenzo , Smith Peter C. B. 
Published: August 2024

Abstract
Ultra-hot Jupiters (UHJs) are among the best targets for atmospheric characterization at high spectral resolution. Resolving their transmission spectra as a function of orbital phase offers a unique window into the 3D nature of these objects. In this work, we present three transits of the UHJ WASP-121b observed with Gemini-S/IGRINS. For the first time, we measure the phase-dependent absorption signals of CO and H2O in the atmosphere of an exoplanet, and we find that they are different. While the blueshift of CO increases during the transit, the absorption lines of H2O become less blueshifted with phase, and even show a redshift in the second half of the transit. These measurements reveal the distinct spatial distributions of both molecules across the atmospheres of UHJs. Also, we find that the H2O signal is absent in the first quarter of the transit, potentially hinting at cloud formation on the evening terminator of WASP-121b. To further interpret the absorption trails of CO and H2O, as well as the Doppler shifts of Fe previously measured with VLT/ESPRESSO, we compare the data to simulated transits of WASP-121b. To this end, we post-process the outputs of the global circulation models with a 3D Monte-Carlo radiative transfer code. Our analysis shows that the atmosphere of WASP-121b is subject to atmospheric drag, as previously suggested by small hotspot offsets inferred from phase-curve observations. Our study highlights the importance of phase-resolved spectroscopy in unravelling the complex atmospheric structure of UHJs and sets the stage for further investigations into their chemistry and dynamics.
Authenticated multi-party quantum key agreement protocol based on cluster states
Authors: Zhang Li , Han Zhaowei , Li Yuehua , Ma Qiuyu , Li Lele 
Published: August 2024

Abstract
Quantum key agreement (QKA) is an important cryptographic primitive that plays a pivotal role in private communications. Authenticated QKA plays an important role in QKA. In this paper, we propose an authenticated multiparty QKA scheme based on 4-qubit cluster states entanglement swapping. The scheme is divided into two parts, the first part is the quantum identity authentication stage, and the second part is the QKA stage. In the quantum identity authentication stage, the participants determine that the participant communicating with them is the claimed person through mutual authentication, which can avoid the impersonation attack of the eavesdropper Eve. In the QKA phase, the participants adopt a bidirectional transmission structure with the participation of a semi-trusted third party, and based on the entanglement swapping property of the 4-qubit cluster state, the QKA is finally realized. Detailed security analysis shows that the protocol can resist a variety of internal and external attacks, such as participants attack, entangle-measure attack, and so on.
Resistive wall tearing mode disruptions
Authors: Strauss H.R. , Chapman B.E. , Lyons B.C. 
Published: August 2024

Abstract
This paper deals with resistive wall tearing mode (RWTM) disruptions. RWTMs are closely related to resistive wall modes. RWTMs are tearing modes whose linear and nonlinear behavior is strongly dependent on the resistive wall outside the plasma. The consequence for ITER, is that the thermal quench timescale could be much longer than previously conjectured. Active feedback stabilization is another possible way to mitigate or prevent RWTM disruptions. Simulations of RWTM disruptions are reviewed for DIII-D and MST. MST has a longer resistive wall time than ITER, and disruptions are not observed experimentally when MST is operated as a standard tokamak. Simulations indicate that the RWTM disruption time scale is longer than the experimental shot time. Edge cooling causes contraction of the current profile, which can destabilize RWTMs. The equilibria studied here have the q = 2 rational surface close to the edge of the plasma, and low current density between the q = 2 surface and the wall. A sequence of low edge current model equilibria has major disruptions only for a resistive, not ideal, wall, and edge

q
⩽
3.4
.

This is consistent with regimes of tokamak disruptivity, suggesting that tokamak disruptions caused by edge cooling at low edge q could be RWTMs.
Research on virtual flight test method for minimum unstick speed of civil aircraft
Authors: Zhang Zhifei 
Published: August 2024

Abstract
The physical process analysis of minimum unstick speed flight test of civilian aircraft is carried out. A simulation environment is built for the virtual flight test based on Simulink and MATLAB script. The pilot control behavior is modeled, and the model control algorithm is given to realize the automation of the simulation process. By comparing with the flight test data, the feasibility of the virtual flight test method is demonstrated, and the improvement direction of the pilot control behavior model is given.
Damage analysis of HTPB propellant based on temperature load test
Authors: Li Jinfei , Zhuang Zhenmin , Qu Kai , Zhang Liping 
Published: August 2024

Abstract
In this paper, the HTPB propellant of a solid rocket motor was taken as the research object. Considering the effect of temperature on the propellant, various types of tests were carried out to study the damage law of the propellant at the macroscopic scale. The aging of HTPB propellant under temperature loading is mainly manifested as oxidative cross-linking of the binder network. The greater the cross-linking degree of the specimen is, the smaller the maximum elongation of the propellant is. Under constant strain load, some AP particles will be dehumidified, and at room temperature, AP particles will decompose slowly, resulting in an increase in strength and a decrease in elongation. The aging of HTPB propellant under constant strain loading at high temperatures is manifested as oxidation cross-linking of the binder network, εm
of propellant declines, and σm
of propellant is reduced.
Research on the flow field characteristics of solid rocket motor work at high altitudes based on immersed boundary method
Authors: Song Daquan , Wang Jian , Lin Qingyu 
Published: August 2024

Abstract
Due to the difficulty of using the body-fitted mesh method to deal with complex moving boundaries, this article proposes to use the immersed boundary method to handle the combustion surface regression generated by the propellant combustion. The effectiveness of the immersed boundary method is verified through simulation calculations of the working process of the rocket engines working at high altitudes, and the flow field characteristics are analysed. The research finds that the higher the flight altitude is, the larger the initial expansion angle of the gas jet, the radial boundary of the jet flow-field, and the length of the jet starting section are. The larger the flight Mach number is, the smaller the initial expansion angle, radial boundary, and length of the starting section of the gas jet are. However, the length of the jet transition section has increased, and the fully developed section of the jet has moved back.