bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chaotic dynamics of a carbon nanotube oscillator with symmetry-breaking
Authors: Wang Zhen , Yang Yantao , Parastesh Fatemeh , Cao Shuping , Wang Jinni 
Published: November 2024

Abstract
Carbon nanotubes (CNTs) are pivotal components in nanoelectromechanical applications. Investgaing the dynamics of CNTs helps in expanding our understanding of their mechanical properties in nanoengineering endeavors. This study delves into the chaotic characteristic of single-walled carbon nanotube (SWCNT) systems involving phase-shifting external excitation and cubic nonlinear damping. Employing compactification theory, we investigate the system’s dynamics at infinity, unveiling its global structure. Analytic solutions for homoclinic/heteroclinic orbits are derived, and utilizing the Melnikov method, we establish criteria for chaos onset in this periodically excited, perturbed SWCNT system. Through bifurcation diagrams, Lyapunov exponent spectra, Poincaré sections, and homoclinic bifurcation surfaces, we empirically confirm the occurrence of chaos, substantiating our theoretical analyses with simulation results.
Organic-inorganic hybrid dye-sensitized solar cells with bismuth ferrite sandwiched between rhodamine-6G and helical ZnO-dense nano-chains
Authors: Bera Amalendu , Sardar R H , Chattopadhyay Sourav 
Published: November 2024

Abstract
Organic–inorganic hybrid dye-sensitized solar cells (DSSC) were grown on a conducting glass substrate employing multiple layers of bismuth-ferrite (BFO) sandwiched between Zinc oxide helical nanochain and Rhodamine- 6 G dye. The zinc oxide layer has been used as a n-type semiconductor window layer. To increase the carrier concentration ZnO has been doped with aluminium. The bismuth ferrite layer served as an electron-blocking layer, while rhodamine 6 g acted as a dye synthesizer. When the window layer is pure ZnO and the BFO layer is properly optimized, solar cell efficiency increases from 0.7% to 1.3%. Aluminum doping in ZnO, combined with an identical BFO layer, increases efficiency from 1.37% to a maximum of 2.1% without employing any kind of electrolyte. Doping the Zn site with Al enhances the efficiency of such a DSSC structure by 1.53 times. BFO limits charge recombination, which leads to enhanced efficiency as an outcome. A parametric analysis was carried out to determine the optimal BFO thickness for increased solar cell efficiency. The main advantages of this optimal DSSC structure are that it is economical, efficient, and does not require any liquid electrolyte. The stability was higher because there was no use of liquid electrolytes.
Two linearized difference schemes on graded meshes for the time-space fractional nonlinear diffusion-wave equation with an initial singularity
Authors: Gahalla Mohmed Elmahdi Emadidin , Yi Yang , Huang Jianfei 
Published: November 2024

Abstract
In this article, two linearized difference schemes are considered to solve a class of time-space fractional nonlinear diffusion-wave equations with weak singularity near the initial time based on its equivalent integro-differential equation. The Crank-Nicolson method combined with the trapezoidal product integration rule with graded meshes is implemented to approximate the Riemann-Liouville integral. The fractional central difference formula and a novel compact difference method are used to construct fully discrete difference schemes. Using the energy method, the stability and convergence of the proposed schemes are demonstrated in terms of the L
2 norm with the accuracy of

O

N

−
min
{
r
σ
,
2
}

+

M

−
2

and

O

N

−
min
{
r
σ
,
2
}

+

M

−
4

, respectively. The theoretical analysis is complemented by numerical results.
Non-monotonically changes in double Schottky barrier of MnCO3–doped ZnO varistors during DC aging
Authors: Lan Peixiang , Zhao Xia , Yue Yinghu , Wang Xin , Zhang Boyu , Lyu Xuebin , Guo Zixin 
Published: November 2024

Abstract
ZnO varistors play a crucial role as core component in metal oxide arresters due to their excellent nonlinear current density-electrical field (J–E) characteristics. After long-term operation under DC stress (DC aging), the J–E curves of ZnO varistors invented in the last decade cross with the original curve. Unexpectedly, the ‘crossover’ phenomenon cannot be explained by the vastly-accepted ion migration mechanism by which the barrier height monotonically declines after DC aging. In the present study, aging and recovery experiments were carried out on MnCO3-doped ZnO varistors. The symmetry of J–E characteristics in the same direction as and the opposite direction to the DC stress was compared, parameters of double Schottky barrier were analyzed, and evolution of point defects was deduced using dielectric spectra. It was found that, in addition to ion migrations, there are electrons ionized by zinc interstitials filling the interface states in the early stage of aging. Because these processes are dominant in different stages, the barrier height changes non-monotonically. MnCO3 can suppress the formation of zinc interstitials, so it simultaneously inhibits ion migrations and filling of the interface states by electrons. When 0.38 mol% MnCO3 is doped, J–E characteristics and the Schottky barrier of ZnO varistors show the smallest deviations during aging and recovery. The findings are helpful in updating criteria for the long-term stability of ZnO varistors and suggest that modifications to their formulae targeting the suppression of the filling the interface states by electrons are also expected to bolster the stability.
Experimental investigation of toe laser intensity effects on capsule compression in indirect-drive inertial confinement fusion
Authors: Yang Weiming , Duan Xiaoxi , Li Yulong , Zhang Yuxue , Jing Longfei , Guan Zanyang , Zhang Chen , Liu Hao , Zhang Huan , Dong Yunsong , Li Zhichao , Yang Dong , Wang Zhebin , Yang Jiamin 
Published: November 2024

Abstract
In indirect-drive inertial confinement fusion (ICF) research, the meticulous design and optimization of laser parameters are crucial for achieving high-gain ignition. The intensity of the toe laser, used for ablating the hohlraum sealing membrane, is a subtle but equally critical parameter. This study introduces a novel experimental approach using the Velocity Interferometer System for Any Reflector (VISAR) to assess the impact of toe laser intensity on the compression of fusion capsules. By tracking the reflectivity of tracer layers and shock velocities in liquid deuterium, the adverse effects of insufficient toe laser intensity on capsule compression have been unveiled for the first time. From a comparison with hydrodynamic simulations, we show that below a critical threshold of 0.23 × 1014 W cm−2, the adiabat, a measure of the fuel’s compression efficiency, increases markedly with the toe laser intensity decreases, whereas it remains stable within the range of (0.23 ∼ 7) × 1014 W cm−2. Our findings provide critical insights on toe laser parameter design, enhancing our understanding of the role of toe laser intensity in ICF experiments. This research not only refines the parameters for laser operation but also underscores the importance of precision in achieving the desired implosion efficiency, contributing to the development of nuclear fusion as a clean energy source.
Unified mesoscale picture of nonlinear generation of zonal flows in toroidal geometry
Authors: Wang Zihao , Wang Shaojie 
Published: November 2024

Abstract
Recent experimental findings on limit-cycle-oscillations indicate that the nonlinear driving of the turbulent poloidal Reynolds stress to zonal flows (ZFs) is not a significant factor in the toroidal geometry, sparking fundamental controversial issues within the fusion community. By using the global nonlinear gyrokinetic simulations, we propose a unified mesoscale picture of nonlinear driving of ZFs in the ion-temperature-gradient turbulence. ZFs are nonlinearly driven by the turbulent energy flux and the turbulent poloidal Reynolds stress. The turbulent energy flux is not shielded by the toroidal geometry effect in nonlinearly driving ZFs. The turbulent poloidal Reynolds stress is not shielded on the time scale shorter than the ion bounce period; however, on the time scale longer than the ion bounce period, the turbulent poloidal Reynolds stress is indeed shielded by the toroidal geometry effect.
Multi-messenger astronomy in the new physics modality with GPS constellation
Authors: Sen Arko P. , Pfeffer Kalia , Ries Paul , Blewitt Geoff , Derevianko Andrei 
Published: November 2024

Abstract
We explore a novel, exotic physics, modality in multi-messenger astronomy. We are interested in exotic fields emitted by the mergers and their direct detection with a network of atomic clocks. We specifically focus on the rubidium clocks onboard satellites of the Global Positioning System. Bursts of exotic fields may be produced during the coalescence of black hole singularities, releasing quantum gravity messengers. To be detectable such fields must be ultralight and ultra-relativistic and we refer to them as exotic low-mass fields (ELFs). Since such fields possess non-zero mass, the ELF bursts lag behind the gravitational waves emitted by the very same merger. Then the gravitational wave observatories provide a detection trigger for the atomic clock networks searching for the feeble ELF signals. ELFs would imprint an anti-chirp transient across the sensor network. ELFs can be detectable by atomic clocks if they cause variations in fundamental constants. We report our progress in the development of techniques to search for ELF bursts with clocks onboard GPS satellites. We focus on the binary neutron star merger GW170817 of August 17, 2017. We find an intriguing excess in the clock noise post LIGO gravitational wave trigger. Potentially the excess noise could be explained away by the increased solar electron flux post LIGO trigger.
A definition of the SI second based on several optical transitions
Authors: Lodewyck Jérôme 
Published: November 2024

Abstract
A new definition of the SI second based on optical transitions is expected to be adopted within the next 10 years. Several options for this redefinition are currently under consideration. Among them, a definition based on several transitions would take advantage of the variety of high performance optical frequency standards. In this paper, we review practical aspects such a definition entails, and propose a detailed analysis of its strengths and weaknesses.
Towards practical quantum secure time transfer
Authors: Villaseñor E. , Shimizu K. , Chandrasekara R. , Lau W. Y. S. , Gensemer S. 
Published: November 2024

Abstract
Accurate clock synchronization and time transfer are vital for positioning, navigation, and timing systems, however, current systems are susceptible to attacks, such as spoofing. Quantum secure time transfer (QSTT) can address this threat by providing a method to validate the authenticity of the time signals used. In this work, we analyze the feasibility of free-space QSTT between two mobile transceivers. Using various techniques, we model the free-space channel to estimate the maximum ranges achievable while guaranteeing a defined level of security. The results indicate that QSTT is feasible for daytime operations up to a distance of 14 km, while nighttime operations can be achieved up to 30 km. This study can be used to design the next pathfinder experiments towards the development of practical QSTT.
REFIMEVE frequency and time network and applications
Authors: Cantin E , Lopez O , Chardonnet C , Amy-Klein A , Rabault M , Coget G , Rosenbusch P , Ménoret V , Quintin N , Tønnes M , Pointard B , Mazouth-Laurol M , Alvarez-Martinez H , Lim C B , Tuckey P , Abgrall M , Le Targat R , Pottie P-E 
Published: November 2024

Abstract
We present the development and current status of the REFIMEVE national research infrastructure, which disseminates time and frequency reference signals generated at LNE-SYRTE to research labs all over France. Using mainly the optical fiber backbone of RENATER, the French National Research and Education Network, REFIMEVE currently provides an optical frequency reference to around 15 labs, and to connection points to Germany, the UK, Italy and Switzerland. The robustness of the various types of equipment specifically developed for the transfer of ultrastable frequencies and the efficient supervision system have enabled us to demonstrate uptimes of over 90%. We show the latest development we have carried out to extend the network to CERN in Switzerland, with a branching link showing residual frequency fluctuations of 3×10−15 for 1 s measurement time, and a few 10−19 at long term. We discuss the issue of data processing for long periods of time and how to mitigate the effects of missing data to achieve reliable link uncertainty estimates. Thanks to these performances, the REFIMEVE network has been used for the precise comparison of primary and optical clocks in Europe, and the REFIMEVE optical signal is currently being exploited in France by user laboratories for photonics, laser stabilisation or control and atomic and molecular high-resolution spectroscopy.
Validating a lutetium frequency reference.
Authors: Arnold K J , Bustabad S , Qi Zhao , Qichen Qin , Zhang Zhiqiang , Zhao Zhang , Barrett M D 
Published: November 2024

Abstract
We review our progress in developing a frequency reference with singly ionized lutetium and give estimates of the levels of inaccuracy we expect to achieve in the near future with both the 1
S
0 ↔ 3
D
1 and 1
S
0 ↔ 3
D
2 transitions. Based on established experimental results, we show that inaccuracies at the low 10−19 level are readily achievable for the 1
S
0 ↔ 3
D
1 transition, and the frequency ratio between the two transitions is limited almost entirely by the BBR shift. We argue that the frequency ratio measured within the one apparatus provides a well-defined metric to compare and establish the performance of remotely located systems. For the measurement of an in situ frequency ratio, relativistic shifts drop out and both transitions experience the same electromagnetic environment. Consequently, the uncertainty budget for the ratio is practically identical to the uncertainty budgets for the individual transitions. If the ratios for two or more systems disagree we can be certain at least one of the clock assessments is incorrect. If they agree, subsequent comparisons on one transition would only differ by relativistic effects. Since motional effects are easily assessed and typically small for a heavy ion, only the differential gravitational red-shift will significantly contribute and this can be confirmed by comparison on the second transition.
A thermal-noise-limited fiber frequency reference with

0.1
Hz
/

Hz

stability
Authors: Zhang Ya , Bandutunga Chathura P. , McRae Terry G. , Gray Malcolm A. , Chow Jong H. 
Published: November 2024

Abstract
We develop an all-passive, fiber frequency reference with a state-of-the-art short-term stability of

0.1
Hz
/

Hz

. We explore the impact of intrinsic fiber thermal noise and show it limits the system in the 1 Hz Fourier frequency band.
Quantum measurement limits to clock precision
Authors: Milburn G J , Kewming M 
Published: November 2024

Abstract
The role of projection noise, an example of quantum measurement noise, in clock design has been well understood for some time. It is based on a particular measurement protocol — Ramsey interferometry. In this paper we discuss more general quantum measurement schemes to estimate the period/frequency of a clock system based on continuous readout of a driven quantum system. The measurement needs to be chosen so as to provide a precise counting signal. We give an example based on a superconducting circuit clock.
Analysis of Stamping Forming and Springback of Arc-shaped Corrugated Diaphragm
Authors: Wang Yu , Zhang Chunguang , Li Shangqing , An Lei , Wu Ye 
Published: November 2024

Abstract
The arc-shaped corrugated diaphragm is the packaging component of pressure sensors, and the quality of diaphragms directly affects the performance of pressure sensors. Diaphragms are usually produced by blanking process. Common production defects include the severe warping and the insufficient forming height. In order to reduce production defects, this paper uses the flat punch and the corrugated punch as research objects to clarify the effect of production process and punch structure on diaphragm production quality. The results show that the production process causes the diaphragm to have a convex warping tendency, which is opposite to the warping tendency caused by corrugation. Moving the corrugation away from the center of the diaphragm and increasing the corrugation spacing can improve the diaphragm quality, while the effect of the corrugation height can be ignored.
Implementation of A Generalized Spring Element for Fastener Simulation of Complex Mechanical Structures In SABRE Software
Authors: Zhang Chang-Xing , Chang Liang , Guo Yu-Chao , Wang Li-Kai 
Published: November 2024

Abstract
When bolts, rivets, and other fasteners in complex engineering machinery structures are modeled using spring elements, internal constraints may arise if the two connected nodes are not coincident, leading to computational errors. To facilitate the modeling of fasteners and extend the application scope of spring elements, this paper constructs a generalized spring element, whose stiffness is calculated using the Huth formula, and deformation is determined by the difference between the two endpoint displacements rigidly transformed to the internal reference point. Based on the characteristics of this element, an explicit expression for the stiffness matrix of the generalized spring element is derived. Accordingly, the implementation of this element has been integrated into the autonomous structural analysis software SABRE. Verification through typical engineering examples shows that the proposed generalized spring element can accurately simulate the load-bearing behavior of fasteners in structures, with analysis errors less than 3% when compared to NASTRAN software.
An online learning-based method for predicting milling energy consumption under tool wear
Authors: Li Mingyao , Zhu Shuo , Jiang Zhigang , Yan Wei , Zhang Hua , Liu Yunhan 
Published: November 2024

Abstract
Accurate prediction of milling energy consumption under tool wear can provide a realistic basis for timely adjustment of process solution and tool replacement. However, complex machining characteristics lead to dynamic changes in tool wear and process parameters, resulting in increased uncertainty in energy consumption deviation, which in turn affects the accuracy of energy consumption prediction. Therefore, this paper proposes an energy consumption prediction method for milling based on BI-SSA-OSELM online learning, considering tool wear. Firstly, the mechanism of tool wear on energy consumption is analyzed from the point of view of material removal power to identify the key factors affecting machining energy consumption. Based on this, cutting and tool geometry parameters are used as model inputs, and the online sequential extreme learning machine (OSELM) algorithm is applied to build the energy consumption model. The model’s hyperparameters are optimized using the sparrow search algorithm (SSA). A drift detection algorithm based on Bernstein’s inequality (BI) is then introduced to guide SSA-OSELM in online learning, to save time for online learning. Results show that the proposed method’s mean absolute error (MAE) is less than 3%, validating the model’s effectiveness and superiority.
Observation of Subsurface Cracks on Flat PEEK Race-Alumina Ball Bearing in Water under 1700 N at 1000 rpm
Authors: Machino Sasuga , Kajiwara Shuhei , Matsubayashi Soji , Kida Katsuyuki 
Published: November 2024

Abstract
Polymers have features of low friction coefficient, chemically resistant, corrosive resistant, and non-conductive. Hence, many tribology productions of polymers such as bearings, gears, and rollers are developed. However, the mechanism of failure such as rolling contact fatigue has not been explained clearly. In recent studies, the observation of subsurface crack growth was important for understanding the failure mechanisms of the polymer ball bearings in water lubrication. In this research, we conducted overall cross-sectional observations to investigate the growth behaviour of subsurface cracks. The cross-sectional areas of the failure were observed. Moreover, we focused on the crack length, depth, angle and direction of propagation of the subsurface cracks. We concluded that as the distance of crack location from the centre of the contact track increased, the depth and length of the subsurface cracks increased. Most of the subsurface cracks propagated from the inner and outer areas toward the centre of the contact track.
LES of flow dynamics downstream of bluff bodies with inclined upper surfaces
Authors: Caban L , Wawrzak A , Tyliszczak A , Thévenin D 
Published: November 2024

Abstract
This study focuses on the flow dynamics downstream of cylindrical bluff bodies with flat, concave, and convex surfaces, where a fuel jet is injected at the bluff body center and the oxidiser flows through a duct surrounding the bluff body. The flow is assumed to be non-reactive and the main attention is put to the mixing process. The research is carried out using the Large Eddy Simulation (LES) method, employing two computational codes: ANSYS Fluent and an in-house high-order code SAILOR. We analyze the extent to which the inclination of the upper bluff body surface modifies the flow behavior in its immediate vicinity and how it affects the size and position of a recirculation zone formed downstream.
Development of triple-helical recombinant collagen-silver hybrid nanofibers for anti-methicillin-resistant Staphylococcus aureus (MRSA) applications
Authors: Fu Caihong , Ma Jianrui , Liu Guangyu , Fan Yirui , Wei Nannan , Xiao Jianxi 
Published: November 2024

Abstract
The escalating threat of healthcare-associated infections highlights the urgent need for biocompatible antibacterial materials that effectively combat drug-resistant pathogens. In this study, we present a novel fabrication method for triple-helical recombinant collagen (THRC)-silver hybrid nanofibers, specifically designed for anti-methicillin-resistant staphylococcus aureus (MRSA) applications. Utilizing a silver-mediated crosslinking strategy, we harness a low-power 38 W lamp to enable silver ions (Ag+) to mediate crosslinking across various proteins. Mechanistic insights reveal the pivotal role of nine amino acids in facilitating this reaction. The THRC maintains its native structure, forming well-ordered nanofibers, while other globular proteins form a distinctive network-like structure. THRC also serves as a reducing and dispersing agent, facilitating the in situ synthesis of highly dispersed silver nanoparticles (AgNPs) (∼7 nm in diameter) within the nanofibers. Systematic investigation of the reaction conditions between THRC and Ag+ demonstrates the versatility of this novel approach for nanofiber fabrication. The incorporation of AgNPs imparts exceptional antibacterial activity to the THRC/AgNPs nanofibers, exhibiting a minimum inhibitory concentration of 19.2 mg l−1 and a minimum bactericidal concentration of 153.6 mg l−1 against MRSA. This innovative approach holds significant potential for developing antibacterial protein-based biomaterials for infection management in wound healing and other biomedical applications.