bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis on optical, thermal and third-order nonlinear properties of L-histidine hydrochloride monohydrate single crystal
Authors: Badoni Ayush , Kiran  , Vijayan N , Joshi Divyansh , Jyoti  , Kumar Kapil , Srivastava Stuti , Prakash Jai 
Published: August 2024

Abstract
This research contributes valuable insights into the understanding of third-order nonlinear optical effects in L-histidine hydrochloride monohydrate (LHHC) single crystal, offering a foundation for future work in optimizing its properties for practical applications in the field of nonlinear optics. It presents a systematic analysis into the LHHC crystal properties harvested by slow evaporation solution (SEST) method. Originally, structure of the compound was confirmed through single crystal x-ray diffraction and powder x-ray diffraction analysis. FTIR analysis was performed to get information about molecular composition of the compound. The assessment of the optical quality of LHHC single crystal was done by UV–Visible and photoluminescence spectroscopies. TG-DTA was employed to assess the stability of the single crystal under different temperature conditions. Z-scan technique, with an open aperture (OA) & closed aperture (CA) configuration, was employed to comprehensively explore the third-order nonlinear response of LHHC single crystal. The nonlinear absorption coefficient β is determined to be 5.32 × 10−10 cm W−1. The NLR index (n2) is calculated as −2.72 × 10−15 cm2 W−1.
A note on field equations in generalized theories of gravity
Authors: Peng Jun-Jin 
Published: August 2024

Abstract
In the work [Phys. Rev. D
84, 124 041 (2011)], to obtain a simple and economic formulation of field equations for generalised theories of gravity described by the Lagrangian

−
g

L

g

α
β

,

R

μ
ν
ρ
σ

, the key equality

∂
L

/

∂

g

μ
ν

R

α
β
κ
ω

=
2

P

μ

λ
ρ
σ

R

ν
λ
ρ
σ

was derived. In this note, it is demonstrated that such an equality can be directly derived from an off-shell Noether current associated with an arbitrary vector field. As byproducts, a generalized Bianchi identity related to the divergence for the expression of field equations, together with the Noether potential, is obtained. On the basis of the above, we further propose a systematic procedure to derive the equations of motion from the Noether current, and then this procedure is extended to more general higher-order gravities endowed with the Lagrangian encompassing additional terms of the covariant derivatives of the Riemann tensor. To our knowledge, both the detailed expressions for field equations and the Noether potential associated with such theories are first given at a general level. All the results reveal that using the Noether current to determine field equations establishes a straightforward connection between the symmetry of the Lagrangian and the equations of motion and such a remedy even can avoid calculating the derivative of the Lagrangian density with respect to the metric.
SPPs based nano refractive index sensor for sodium and potassium ion concentration detection in human blood
Authors: Wang Jin , Yan Shubin , Liu Feng , Chen Changxin , Yan Xiaoran , Xu Aiwei , Wu Taiquan 
Published: August 2024

Abstract
In this paper, a micro-nano sensing configuration constructed from MIM waveguide and a semicircular cavity with annular cavity (SCAC) based on surface plasmon polaritons(SPPs) is submitted. And the sensing property of the waveguide coupling construction is investigated using the finite element method. The optimization emulation results show that the broadband mode generated by the two rectangular cavities on the bus waveguide interacts with the narrowband mode generated by the main construction SCAC, and the radiation spectroscopy of the system appears to be significantly sharp and asymmetric, which is the Fano resonance phenomenon. The impact of external environmental changes on the capability of the sensing structure was investigated by altering the geometric argument of the designed structure afterwards. The final system can achieve a sensitivity of 2600 nm RIU−1 and a figure of merit (FOM) of 47.27. It was then applied to biosensing and its sensitivity as a human sodium and potassium ion concentration detection sensor was investigated and the best can be achieved at 0.415

mgd
l

−
1

and 0.525

mgd
l

−
1

.
The influence of jet on aerodynamic noise in the pantograph area at different sinking heights
Authors: Cao Yangyang , Zhang Jiye , Shi Jiawei , Ma Yuzhe 
Published: August 2024

Abstract
The influence mechanism of jet on aerodynamic noise control in the pantograph region at different sinking heights was numerically studied using an Improved Delayed Detached Eddy Simulation (IDDES) model and the Ffowcs Williams-Hawkings (FW-H) equation. Active flow control was achieved by setting jet slots at the leading edge of the cavity to predict the noise generated by the jet itself. The results showed that in the pantograph region with a sinking height of 500 mm, the shear layer was lifted by the jet, which prevented high-speed turbulence caused by flow separation from entering the cavity. Therefore, the model with jet control device reduced the overall far-field noise on the side of the pantograph by 1.6 ∼ 3.9 dB. Through flow field analysis, for the pantograph region where flow separation occurs in the front of the cavity, the jet needs to lift the shear layer enough to cross the front of the pantograph and prevent flow separation, thereby reducing the aerodynamic noise. For the pantograph region without flow separation in the front of the cavity, the jet may introduce additional noise sources, deteriorating the aerodynamic noise in the pantograph region.
Analytical study of the thermoelectric properties in silicene
Authors: Amarnath R , Bhargavi K S , Kubakaddi S S 
Published: August 2024

Abstract
Theoretically, we investigate the thermoelectric (TE) properties namely, electrical conductivity (σ), diffusion thermopower (S
d), power factor (PF), electronic thermal conductivity (κ
e) and thermoelectric figure of merit (ZT) for silicene on Al2O3 substrate. TE coefficients are obtained by solving the Boltzmann transport equation taking account of the electron scattering by all the relevant scattering mechanisms in silicene, namely charged impurity (CI), short-range disorder (SD), intra- and inter-valley acoustic (APs) and optical (OPs) phonons, and surface optical phonons (SOPs). The TE properties are numerically studied as a function of temperature T (2–400K) and electron concentration n
s(0.1–10 × 1012 cm−2). The calculated σ and S
dare found to be governed by CIs at low temperatures (T< ∼ 10 K), similar to that in graphene. At higher T, they are found to be mainly dominated by the intra- and inter-valley APs. The resultant σ (S
d) is found to decrease (increase) with increasing T, whereas PF remains nearly constant for T> ∼ 100 K. On the other hand, n
s dependence shows that σ (S
d) increases (decreases) with increasing n
s; with PF relatively constant at lower n
s and then decreases with increasing n
s. At room temperature, the calculated σ (S
d) in silicene is closer to that in graphene and about an order of magnitude greater (less) than that in monolayer (ML) MoS2. The κ
e is found to be weakly depending on T and Wiedemann–Franz law is shown to be violated. We have predicted a maximum PF ∼3.5 mW m−1 K−2, at 300 K for n
s = 0.1 × 1012 cm−2 from which the estimated ZT = 0.11, taking a theoretically predicted lattice thermal conductivity κ
l = 9.4 Wm−1 K−1, is a maximum. This ZT is much greater than that of graphene and ML MoS2. The ZT is found to decrease with the increasing n
s. The ZT values for other values of n
s in silicene, at 300 K, also show much superiority over graphene, thus making silicene a preferred thermoelectric material because of its relatively large σ and very small κ
l.
Plug-and-play four-state modulation continuous-variable quantum key distribution
Authors: Zhou Jian , Li Hui , Feng Yanyan , Shi Ronghua , Shi Jinjing 
Published: August 2024

Abstract
In this paper, a novel and highly efficient secure communication scheme is proposed through the integration of four-state modulation quantum key distribution and plug-and-play technology. This scheme serves the purpose of transmitting information reliably while preserving data confidentiality between two communicating parties. The most important advantage of the proposed continuous-variable QKD system is that the birefringence effect in fiber can be compensated automatically. Notably, simulation experimental evaluations are conducted, unveiling the performance of the plug-and-play four-state QKD which is as good as the four-state protocol when having small Rayleigh scattering noise. Furthermore, we conduct a comprehensive analysis of potential security threats targeted at the proposed protocol, thereby substantiating its robustness against such attacks. Moreover, theoretical justifications are provided to validate the security of the proposed scheme.
Transition to chaos in magnetized rotating Rayleigh-Bénard convection
Authors: Oliveira Dalton N , Chertovskih Roman , Rempel Erico L , Franco Francis F 
Published: August 2024

Abstract
Transition to chaos and magnetic field generation are investigated in numerical simulations of three-dimensional rotating Rayleigh-Bénard convection. The behavior of the system is explored as a function of the rotation speed, measured by the Taylor number, the thermal buoyancy strength, measured by the Rayleigh number, and the magnetic Prandtl number. In the absence of magnetic field, a detailed exploration of the space of parameters reveals a sequence of Hopf bifurcations leading to quasiperiodicity and chaos. It is shown that rotation can dampen convection for low values of the Rayleigh number, but if buoyancy is strong enough to keep the convection, then rotation facilitates transition to chaos. In the presence of a weak seed magnetic field, convective motions may trigger a nonlinear dynamo that converts kinetic energy into magnetic energy, leading to an exponential increase of the magnetic energy. A nonhysteretic blowout bifurcation is shown to be responsible for the onset of the dynamo regime for a critical magnetic Prandtl number, whose value depends on the rotation rate.
Collision dynamics between breather and lump-type localized waves in the (3+1)-dimensional shallow water wave equation
Authors: Tang Yuan , Wang Chuanjian , Liu Qingxing , Li Changzhao 
Published: August 2024

Abstract
In this paper, the collision dynamics of breather and lump-type localized waves in the (3+1)-dimensional shallow water wave equation are investigated in detail. Firstly, the auto-Bäcklund transformation and the linear representation of the (3+1)-dimensional shallow water wave equation are derived in virtue of the truncated Painlevé expansion method, which provide convenience in solving the (3+1)-dimensional shallow water wave equation. Secondly, based on the linear representation and the principle of linear superposition, the rational solutions in the exponential and polynomial forms are constructed. Tuning the free parameters of the rational solutions, localized waves of various patterns are obtained such as breather, lump-type localized waves and their hybrid structure. The anomalous inelastic interaction phenomenons of breather and lump-type localized waves are exhibited. Thirdly, combining the large-time behaviors of solution with the velocity relationship of localized waves, the dynamical properties and the classification of localized wave solutions are discussed in detail. Finally, we discuss the bound state of breather and lump-type localized waves under the velocity resonance condition, three different types of lump-breather molecules are displayed. The obtained results further enrich the structures and dynamical behaviors of localized waves. It is expected that the interaction phenomena taking place in the (3+1)-dimensional shallow water wave equation will be helpful in predicting or controlling some related shallow water wave phenomena.
Advanced error correction method for quantum key distribution in IoT systems
Authors: Guitouni Zied , Maize Sirine , Zrigui Mounir , Machhout Mohsen 
Published: August 2024

Abstract
The secure distribution of keys is essential to ensuring the privacy and integrity of data in Internet of Things (IoT) systems. Quantum Key Distribution (QKD) protocols, such as BB84, use principles from quantum mechanics to establish secure communication channels. However, errors that occur during the transmission of qubits can compromise the reliability of the shared key. This paper presents a new method for error correction that integrates Convolutional Neural Networks (CNNs) into the BB84 protocol for QKD in IoT systems. By harnessing the exceptional pattern recognition capabilities of CNNs, our approach learns hierarchical representations from preprocessed quantum channel data to effectively identify and correct errors. Extensive simulations demonstrate the high performance of our CNN-based method in reducing the Quantum Bit Error Rate (QBER). This contribution significantly enhances the security and reliability of key distribution, offering a promising solution for robust quantum communication in IoT environments.
Dielectric resonator antenna with square slot dgs and amc support for gain enhancement
Authors: Ch Raghavendra , M Neelaveni Ammal , Madhav B T P 
Published: August 2024

Abstract
A miniatured Dielectric Resonator Antenna (DRA) designed on Defected ground structure (DGS) with backing of Artificial Magnetic Conductor (AMC) is presented in this work. The designed antenna showing wide bandwidth to cover WLAN, Wi-Fi and 5G communication applications under sub 6 GHz range and X-band for satellite communication device applications. Antenna occupying the dimension of 35 × 30 × 1.6 mm on Rogers RT-duroid 5880 substrate material, DRA on alumina material of permittivity 9.8 with dimension of 25 × 20 × 10 mm and the AMC surface of dimension 60 × 58 × 1.6 mm on FR4 substrate material. The constructed antenna resonating in the wide band from 3.4–11.5 GHz by holding overall bandwidth of 8.11GHz and an impedance bandwidth of 139%. The DRA placed over the antenna providing the axial ratio at two bands of 4.2–6 GHz and 9.2 to 11.4 GHz with axial bandwidth of 36% and 28% respectively. The placement of AMC structure beneath the antenna exhibiting an improvement in gain of 9% and an average gain attained in the operating band is around 7.2 dBi. The unique combination of monopole antenna with DRA and AMC providing excellent bandwidth, axial ratio and gain.
Optical design of the time-resolved ARPES beamline of the new material spectroscopy experimental station for the update of CAEP THz-FEL facility
Authors: Du 杜 Liang-Liang 亮亮 , Meng 孟 Li-Min 立民 , Li 李 Jiang 江 , Zhu 朱 Li-Guo 礼国 
Published: August 2024

Abstract
The Chinese Academy of Engineering Physics Terahertz Free Electron Laser Facility (CAEP THz FEL, CTFEL) is the only high-average power free electron laser terahertz source based on superconducting accelerators in China. The update of the CTFEL is now undergoing and will expand the frequency range from 0.1–4.2 THz to 0.1–125 THz. Two experimental stations for material spectroscopy and biomedicine will be built. A high harmonic generation (HHG) lightsource based beamline at the material spectroscopy experimental station for time-resolved angle-resolved photoemission spectroscopy (ARPES) research will be constructed and the optical design is presented. The HHG lightsource covers the extreme ultraviolet (XUV) photon energy range of 20–50 eV. A Czerny–Turner monochromator with two plane gratings worked in conical diffraction configuration is employed to maintain the transmission efficiency and preserve the pulse time duration. The calculated beamline transmission efficiency is better than 5% in the whole photon energy range. To our knowledge, this is the first time in China to combine THz-infrared FEL with HHG light source, and this experimental station will be a powerful and effective instrument that will give new research opportunities in the future for users doing research on the dynamic evolution of the excited electron band structure of a material’s surface.
Multidimensional images and aberrations in STEM
Authors: Hoglund Eric R. , Lupini Andrew R. 
Published: August 2024

Abstract
Recent advances in scanning transmission electron microscopy (STEM) have led to increased development of multi-dimensional STEM imaging modalities and novel image reconstruction methods. This interest arises because the main electron lens in a modern transmission electron microscope usually has a diffraction-space information limit that is significantly better than the real-space resolution of the same lens. This state-of-affairs is sometimes shared by other scattering methods in modern physics and contributes to a broader excitement surrounding multidimensional techniques that scan a probe while recording diffraction-space images, such as ptychography and scanning nano-beam diffraction. However, the contrasting resolution in the two spaces raises the question as to what is limiting their effective performance. Here, we examine this paradox by considering the effects of aberrations in both image and diffraction planes, and likewise separate the contributions of pre- and post-sample aberrations. This consideration provides insight into aberration-measurement techniques and might also indicate improvements for super-resolution techniques.
Excitonic optical properties in monolayer SnP2S6
Authors: Chen 陈 Peng-Yuan 鹏远 , Quan 权 Zhen 真 , Wang 王 Shu-Dong 舒东 
Published: August 2024

Abstract
Quantum confinement effect and reduced dielectric screening in two-dimensional (2D) dramatically enhance the electron–hole interactions. In this work, we use many-body perturbation theory and Bethe–Salpeter equation (BSE) to investigate the electronic and excitonic optical properties of monolayer SnP2S6. Our findings reveal that the excitonic effect dominates the optical absorption spectra in the visible light range, and the lowest-energy exciton X
0 in monolayer SnP2S6 is optically bright with the binding energy of 0.87 eV and the radiative lifetime of ∼ 10−11 s, which is highly advantageous to the photo-luminescence. Most importantly, the absence of optically forbidden states below the bright states X
0 would give rise to a high quantum efficiency of 2D SnP2S6. We also find that applied biaxial strain can further shorten the radiative lifetime of the bright states. These results imply that 2D SnP2S6 is a promising candidate for the optoelectronic devices.
An integral approach to plasma-wall interaction modelling for EU-DEMO
Authors: Matveev D. , Baumann C. , Romazanov J. , Brezinsek S. , Ratynskaia S. , Vignitchouk L. , Tolias P. , Paschalidis K. , Tskhakaya D. , Komm M. , Podolník A. , Mougenot J. , Charles Y. , Delaporte-Mathurin R. , Hodille E. , Grisolia C. , Montupet-Leblond F. , Schmid K. , Von Toussaint U. , Granberg F. , Kporha F. , Kovačič J. , Costea S. 
Published: August 2024

Abstract
An integral approach to plasma-wall interaction (PWI) modelling for DEMO is presented, which is part of the EUROfusion Theory and Advanced Simulation Coordination activities that were established to advance the understanding and predictive capabilities for the modelling of existing and future fusion devices using a modern advanced computing approach. In view of the DEMO design, the aim of PWI modelling activities is to assess safety-relevant information regarding the erosion of plasma-facing components (PFCs), including its impact on plasma contamination, dust production, fuel inventory, and material response to transient events. This is achieved using a set of powerful and validated computer codes that deal with particular PWI aspects and interact with each other by means of relevant data exchange. Steady state erosion of tungsten PFC and subsequent transport and re-deposition of eroded material are simulated with the ERO2.0 code using a DEMO plasma background produced by dedicated SOLPS-ITER simulations. Dust transport simulations in steady state plasma also rely on the respective SOLPS-ITER solutions and are performed with the MIGRAINe code. In order to improve simulations of tungsten erosion in the divertor of DEMO, relevant high density sheath models are being developed based on particle-in-cell (PIC) simulations with the state-of-the-art BIT code family. PIC codes of the SPICE code family, in turn, provide relevant information on multi-emissive sheath physics, such as semi-empirical scaling laws for field-assisted thermionic emission. These scaling laws are essential for simulations of material melting under transient heat loads that are performed with the recently developed MEMENTO code, the successor of MEMOS-U. Fuel retention simulations assess tritium retention in tungsten and structural materials, as well as fuel permeation to the coolant, accounting for neutron damage. Simulations for divertor monoblocks of different sizes are performed using the FESTIM code, while for the first wall the TESSIM code is applied. Respective code-code dependencies and interactions, as well as modelling results achieved to date are discussed in this contribution.
Development and study of ultrasonic pulse velocity measurement system using wave analysis and two-point detection approach
Authors: Piyush  , Yadav Sanjay , Dubey P.K. 
Published: August 2024

Abstract
This article focuses on the development and analysis of an
Ultrasonic Pulse Velocity (UPV) measurement system used for the
evaluation of concrete and Reinforced Cement Concrete (RCC) in civil
construction. The UPV tester is essential for on-site assessments of
structures, as it is used to measure the velocity of ultrasonic
waves within the material, directly correlating with its
strength. UPV testing is affected by the attenuation of ultrasonic
waves in concrete, particularly due to the interfacial transition
zone. Excess ultrasonic attenuation results in the reduction in the
received signal amplitude which may also results in the omission of
the initial pulses due to threshold comparison at the receiver. The
study highlights the impact of receiver gain on threshold error and
discusses the limitations associated with ADC sampling rate and
amplitude resolution. UPV measurement, including counter or data
acquisition approach, have error contributions associated with
threshold voltage comparison. The error due to threshold amplitude
selection is quantified, emphasizing the importance of accurate
signal analysis, particularly in highly attenuating medium. The
article presents the design and development of a PC-based UPV tester
with automatic threshold error compensation. The system includes a
transmitter, receiver, 32-bit microcontroller, and a Graphical User
Interface (GUI) for data analysis. The article introduces a
two-point linear detection logic to minimize errors caused by
selected signal amplitude and omission of initial pulses in transit
time measurements. The proposed method provides effective resolution
of 10 ns through software, even at low sampling rate of
2 MS/s. The experimental results demonstrate the effectiveness of
the developed UPV tester, with comparisons to a reference
calibration facility at CSIR-NPL. The standard deviation in the
ultrasonic transit time measurement by the developed UPV device,
with threshold error correction, was ±70 ns.