bluuebunny/crossref_metadata_2025_split huggingface dataset:
Powering an autonomous clock with quantum electromechanics
Authors: Culhane Oisín , Kewming Michael J , Silva Alessandro , Goold John , Mitchison Mark T 
Published: January 2024

Abstract
We theoretically analyse an autonomous clock comprising a nanoelectromechanical system, which undergoes self-oscillations driven by electron tunnelling. The periodic mechanical motion behaves as the clockwork, similar to the swinging of a pendulum, while induced oscillations in the electrical current can be used to read out the ticks. We simulate the dynamics of the system in the quasi-adiabatic limit of slow mechanical motion, allowing us to infer statistical properties of the clock’s ticks from the current auto-correlation function. The distribution of individual ticks exhibits a tradeoff between accuracy, resolution, and dissipation, as expected from previous literature. Going beyond the distribution of individual ticks, we investigate how clock accuracy varies over different integration times by computing the Allan variance. We observe non-monotonic features in the Allan variance as a function of time and applied voltage, which can be explained by the presence of temporal correlations between ticks. These correlations are shown to yield a precision advantage for timekeeping over the timescales that the correlations persist. Our results illustrate the non-trivial features of the tick series produced by nanoscale clocks, and pave the way for experimental investigation of clock thermodynamics using nanoelectromechanical systems.
Computation of reverse neighbourhood degree-based topological indices for the transition metal phthalocyanine polymers (poly-TMPc)
Authors: Abirami S Jeyamangala , Raj S Angelin Kavitha , Siddiqui Muhammad Kamran 
Published: January 2024

Abstract
In this article, we discuss the reverse neighbourhood degree-based topological indices for the transition metal phthalocyanine polymers (poly- TMPc). Degree-based topological indices have been extensively studied and linked to a variety of chemical properties. An even more recently established methodology for assessing chemical systems and geometries is the use of numerical descriptors based on the degree of definition defined by the reverse-degree concept technique. It highlights molecular characteristics as numerical descriptors based on the reverse-degree concept’s degree of definition and delivers numerical descriptors in algebraic form. On the other hand, due to their high catalytic activity, photostability, resistance to severe environments, and adaptable properties, transition metal phthalocyanines are a fascinating class of organic semiconductors. Furthermore, different types of reverse neighbourhood topological indices, such as the augmented Zagreb index, first and second Zagreb indexes, and Randi

c

́

indexes, are defined and used to assess the complexity, stability, and other properties of poly-TMPc(m,n).
Multi-zone taylor expansion method for broadband achromatic polarization-insensitive metalens design
Authors: Song Ruixiang , Lu Xutong , Wang Feng , Song Xiyao , Chen Zhangyuan , Li Yanping 
Published: January 2024

Abstract
Broadband achromatic polarization-insensitive metalens with large numerical aperture (NA), large diameter and high efficiency are in demand. Existing methods can dramatically improve one of the above performances at the expense of the others. In this work, the multi-zone Taylor expansion method (MZTEM) is proposed to reduce these trade-offs between different key figures of merit. In this method, a metalens is devided into odd ring and even ring regions, then the odd (even) ring metalens focus peak is shifted forward with tailored functions of even (odd) ring region, and finally the arrangement of the meta-units is optimized to get higher efficiency. Based on the MZTEM, an achromatic polarization-insensitive lithium niobate on insulator (LNOI) metalens is designed working in the visible from wavelength λ = 430 nm to 750 nm, which exhibits a focusing efficiency of 35%–63% and NA of 0.255. Besides, the full width at half maxima (FWHM) variation is less than 0.14 μm and the focusing efficiency variation is less than 2% within 0°–10° incidence angle.
Smart alloy metalized novel photonic NEMS photodiode with CuAlV/n-Si/Al junction structure
Authors: Karaduman Oktay , canbay Canan Aksu , Dere Aysegul , Orman Yusuf , Al-Ghamdi Ahmed A , Al-Sehemi Abdullah G , Yakuphanoglu Fahrettin 
Published: January 2024

Abstract
In this work, a novel smart (shape memory) alloy metalized photonic silicon wafer photodiode with Schottky type CuAlV/n-Si/Al contact structure as a nano-electro-mechanical-system (NEMS) photodevice was fabricated by thermal evaporation technique. The CuAlV memory alloy used as the top Schottky metal contact electrode was produced by arc melting technique and a subsequent quenching in an iced-brine water medium, and its shape memory effect characteristics were revealed by thermal and structural tests. The fabricated photonic NEMS photodiode was characterized by different photo-electrical (I-V, I-t) and frequency/time dependent and illuminated capacitance (C–V/f, C-t, C–V/ill.) and conductance-voltage (G-V) measurements under different frequencies and artificial light intensity power conditions. The I-V tests showed an excellent current rectifying ability and very well net photocurrent generation features of the photodiode. The specific detectivity of the photodiode was found as high as almost approaching 1011 Jones. The SCLC (space charge limited current conduction) analyses made on the double-log I-V plots of the photodiode revealed that the trap-filling TFL-SCLC and trap-free SCLC current conduction mechanisms are the two prevailing conduction mechanisms in the forward bias voltage region. The density of interface states (Dit) of the fabricated photodiode was determined. Moreover, an excellent reproducibility of light-induced photocapacitance formation of the novel photodiode was demonstrated by C–V/t measurements under different artificial light power intensities.
Line identification of extreme ultraviolet spectra from aluminum ions in EAST Tokamak plasmas
Authors: Zhang Fengling , Zhang Ling , Zhang Wenming , Cheng Yunxin , Hu Ailan , Ding Xiaobin , Morita Shigeru , Li Zhengwei , Zhou Zhen , Cao Yiming , Ma Jiuyang , Xu Zhehao , Xu Lang , Zhou Chengxi , Jie Yinxian , Mitnik Darío 
Published: January 2024

Abstract
Extreme ultraviolet (EUV) spectra emitted from aluminum in the 5-340 Å wavelength range were observed in Experimental Advanced Superconducting Tokamak (EAST) discharges. Several spectral lines from aluminum ions with different degrees of ionization were successfully observed with sufficient spectral intensities and resolutions using three fast-time-response EUV spectrometers. The line identification uses three independent state-of-art computational codes for the atomic structure calculations, which provide the wavelengths and the collisional and radiative transition rate coefficients. These programs are hullac (Hebrew University—Lawrence Livermore Atomic Code), autostructure, and fac (Flexible Atomic Code). Using three different codes allows us to resolve some ambiguities in identifying certain spectral lines and assess the validity of the theoretical predictions.
Quantum coherence and Rényi mutual information in Heisenberg XYZ system under non-uniform field
Authors: Ye Biaoliang , Zhang Zhanjun 
Published: January 2024

Abstract
We investigate the thermal and magnetic quantum coherence in the Heisenberg XYZ system. To accomplish this, we employ three measures: the L1 norm coherence, the relative entropy coherence, and the Rényi mutual information (RMI). By performing these measures, we can accurately describe the quantum behaviors of the Heisenberg XYZ system. During the process of characterization, we have found both similarities and distinctive properties. Under a non-uniform field, the magnetic field can enhance the RMI for different coefficients α. All of the analytical and numerical results are described in details.
Intracavity heterodyne laser interferometry. Studies of the features of optical Kerr effect in the atmosphere
Authors: Gelikonov V M , Novikov M A 
Published: January 2024

Abstract
The features of high-sensitivity frequency and phase measurements in a He–Ne gas laser at a wavelength of 0.63 μm are considered. The single-frequency mode of this laser with a large excess of the lasing threshold is implemented due to longitudinal mode selection using an ultra-thin nickel metal film placed in the standing field node of the cavity. With such an excess of the lasing threshold, the natural linewidth component is very small (∼10−3Hz), which was determined from the heterodyne method of measuring natural fluctuations of lasing frequency. This method can be used in combination with the multibeam intracavity interferometry for measuring phase modulation at a level of 10−9 rad Hz−1/2. To demonstrate the capabilities of the method, the electro-optical Kerr effect in air at atmospheric pressure in linearly polarized light was studied separately for extraordinary and ordinary waves. The Kerr and the Havelock constants were measured. A deviation from a purely quadratic dependence determined by the fourth power of the amplitude of a low-frequency electric field was found. A possible explanation of the detected deviation from the Kerr effect is the electrostriction.
Comparative analytical and numerical investigation of the plasma density in atmospheric air generated by nanosecond laser pulses
Authors: Delibašić Marković H , Kaleris K , Papadogiannis N A , Petrović V 
Published: January 2024

Abstract
Energy deposition via laser-induced breakdown (LIB) in gases or other media and its accompanying secondary light and sound radiative processes are nowadays increasingly deployed in scientific and technological applications. The modeling and control of the breakdown and radiative processes occurring by the interactions of the free electrons with the heavy particles in the partially ionized medium, requires precise spatio-temporal description of the generated free electron density. This work presents an analysis of a free electron rate model describing the free electron density in air plasmas produced by nanosecond laser pulses. The model accounts for multiphoton and cascade ionization, and for electron diffusion, recombination, and attachment. A closed-form expression of the rate model is derived and validated by comparison with experimentally validated numerical solutions, showing very good agreement in a wide range of parameters. Simulation results are presented for different laser pulses and focal spot sizes and analysis is carried out regarding the dependence of the air plasma on the various laser radiation parameters. The presented approach is particularly useful for complex multi-scale models calculating the electron and ion temperature evolution, the thermoelastic expansion and the shock-wave following LIB of gases.
Non-stationary quasi-classical states of a charged particle in a strong magnetic field under conditions of the dissipative medium
Authors: Sazonov S V 
Published: January 2024

Abstract
Based on the quasi-classical approximation, a general approach is proposed for constructing non-stationary quantum states of a charged particle in a magnetic field, when the dissipative forces of viscous friction and drag, proportional to the velocity and the square of the velocity, respectively, are also significant. The corresponding quasi-classical Green’s function is found, with the help of which the squeezed and coherent states of the particle are studied. It is shown that the dissipation and a magnetic field suppress the quantum properties of the particle. This is especially true for the transverse motion with respect to the magnetic field. Over time, the coherent and squeezed states transform into the same static state, which is characterized by a zero uncertainty of the transverse coordinates and an uncertainty of the longitudinal coordinate, which contains information about the initial velocity of the particle.
Exploration of the ground state properties of neutron-rich sodium isotopes using the deformed relativistic mean field theory in complex momentumrepresentations with BCS pairings*
Authors: Luo 罗 Yu-Xuan 雨轩 , Liu 刘 Quan 泉 , Guo 郭 Jian-You 建友 
Published: January 2024

Abstract
This study explores the ground-state characteristics of neutron-rich sodium isotopes, encompassing two-neutron separation energies, root-mean-square radii, quadrupole moments of proton and neutron distributions, single-particle levels of bound and resonant states, and neutron density distributions and shapes. Simultaneously, special attention is paid to the distinctive physical phenomena associated with these isotopes. The deformed relativistic mean field theory in complex momentum representations with BCS pairings (DRMF-CMR-BCS) employed in our research provides resonant states with real physics, offering insights into deformed halo nuclei. Four effective interactions (NL3, NL3*, PK1, and NLSH) were considered to assess the influence of continuum and deformation effects on halo structures. Calculations for odd-even nuclei 35–43Na revealed the dependence on the chosen effective interaction and number of considered resonant states. Neutron occupation patterns near the Fermi surface, particularly in orbitals

and

, were determined to be crucial in halo formation. The study provided detailed insights into the density distributions, shape evolution, and structure of neutron-rich sodium isotopes, contributing valuably to the field of nuclear physics.
Astrophysical S-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model*
Authors: Dubovichenko S. B. , Tkachenko A. S. , Kezerashvili R. Ya. , Burkova N. A. , Yeleusheva B. M. 
Published: January 2024

Abstract
We study radiative

capture on the ground state of 16O at stellar energies within the framework of a modified potential cluster model (MPCM) with forbidden states, including low-lying resonances. The investigation of the 15N(

)16O reaction includes the consideration of

resonances due to

transitions and the contribution of the

scattering wave in the p + 15N channel due to the

transition. We calculated the astrophysical low-energy S-factor, and the extrapolated

turned out to be within 34.7−40.4 keV·b. The important role of the asymptotic constant (AC) for the 15N(

)16O process with interfering

(312) and

(962) resonances is elucidated. A comparison of our calculation for the S-factor with existing experimental and theoretical data is addressed, and a reasonable agreement is found. The reaction rate is calculated and compared with the existing rates. It has negligible dependence on the variation of AC but shows a strong impact of the interference of

(312) and

(962) resonances in reference to the CNO Gamow windows, especially at low temperatures. We estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from Phys. Rev. C. 85, 065810 (2012). The reaction rate enhancement due to the cascade transitions is observed from

and reaches the maximum factor ~ 1.3 at

. We present the Gamow energy window and a comparison of rates for radiative proton capture reactions 12N(

)13O, 13N(

) 14O, 14N(

)15O, and 15N(

)16O obtained in the framework of the MPCM and provide the temperature windows, prevalence, and significance of each process.
Simulation and Process Analysis of DLP 3D Printing with High-strength Resin
Authors: Sang Jian , Zhao Xinxin , Jiang Kai , Zhao Qiancheng , Wei Chaofei , Li Ming , Hu Leijun , Jin Changxin 
Published: January 2024

Abstract
By utilizing digital light processing (DLP) printing equipment and technology, this study investigates the temperature field, stress changes, and the impact of various process parameters on the formation and strength characteristics of high-strength resin during the printing process. Abaqus birth-death element method simulation and related process tests are employed for this purpose. The simulation results demonstrate a gradual decrease in the temperature field through wavy diffusion from the center to the boundary during printing. The node temperature, displacement, and stress curves are observed to fluctuate frequently due to the subsequent printing layers, with the maximum stress point located close to the printing platform. The experimental results reveal that the test parameters possess different effects on the surface quality and tensile strength. Inappropriate parameters tend to result in surface defects. The influencing factors on the tensile strength of the sample are ranked in the following order: layer thickness, exposure time, and exposure light intensity. The molded resin sample achieves a tensile strength of 58.5MPa, which is comparable to the tensile properties of traditionally injection-molded parts.
Characteristics of welding laser beam and its influence on weld forming coefficient
Authors: Han Lijun , Jia Lei , Yu Wenchao 
Published: January 2024

Abstract
Laser welding is a very complicated process. At present, there is no systematic research on the relationship between welding parameters and forming coefficient. By studying the internal relationship between laser parameters and the characteristics of welding laser, laser beam indexes, such as focusing index, are defined. They are simplified to a few laser parameters so as to facilitate the study of the influence of welding parameters on the forming coefficient. The results show that material, assembly gap, laser power and welding speed have great influence on weld penetration. When the laser power density reaches 106J/cm2, the characteristics of deep penetration welding appear. Under the condition of constant clearance, the weld depth increases with the increase of t/b. The weld penetration increases with the increase of laser power and tends to be stable when the welding speed is 12mm/s. Different materials also have a certain influence on the weld penetration depth. Under the same conditions, X6CrNiTi1810 obtains greater penetration depth, indicating that physical and chemical properties of materials are also one of the factors affecting the penetration depth. The mechanism and condition of laser welding were analysed. The relationship between laser absorptivity of sheet surface and physical properties of the materials is also studied and then obtained. The study will provide theoretical guidance for laser welding process design and welding parameter selection of steel plate.
Experimental study on enhancement condensation heat transfer in tube by foam metal in presence of non-condensable gas
Authors: Li Luyi 
Published: January 2024

Abstract
Condensation heat transfer in tube is widely applied in industrial production, and the heat transfer process is often weakened by non-condensable gas (NCG) in actual production. Enhancing condensation heat transfer is beneficial to improve production efficiency, which has always been a hot topic in current research. Foam metal material with large specific surface area and good thermal conductivity is an ideal material to enhance heat transfer. In order to study enhancement heat transfer effect and optimize structure of foam metal, this paper investigated condensation heat transfer in tube strengthened by foam metal in presence of NCG experimentally. Section shape of foam metal is annular, and the pores per inch (PPI) of foam metals is 10, 15, 20 respectively. The effects of PPI value, steam/air mixture mass flow, and NCG mass fraction on heat transfer coefficient (HTC) and flow resistance are studied. The results reveal the following: (1) Compared with smooth tube, the foam metal enhances heat transfer significantly, and HTC increases by 1.5-2.3 times. (2) At same steam/air mixture mass flow, 10PPI foam metal tube has the highest HTC compared to others. (3) With increase of NCG mass fraction and PPI value, pressure drop increases and the HTC decreases. Based on experimental data, pressure drop and HTC correlations are developed. This paper provides an important technical basis for foam metal material application in enhancement heat transfer area.
Preparation and photocatalytic performance of TiO2/lignin-based carbon composited photocatalyst
Authors: Xu Qiong , Pan Hong , Zhang Wanting , Xu Lihui , Li Tianyang 
Published: January 2024

Abstract
In this study, the lignin-based carbon/TiO2 (LCT) nanocomposite photocatalyst was prepared by the Sol-gel-carbonization method. The raw material of carbon precursor was lignin extracted from coconut by the solvent heating method. The optimal conditions for lignin extraction, such as material ratio, temperature and time, were investigated. The optimum extraction conditions for lignin were determined as follows: material ratio of 1:7, heating time of 4 hours, and heating temperature of 110 °C. The photocatalytic results demonstrated that the prepared LCT exhibited efficient degradation of MO, achieving a degradation efficiency of up to 91.8% within 2 hours, whereas pure TiO2 showed negligible degradation ability under visible light. Moreover, the LCT composite exhibited good stability during the photodegradation process.
Study on Shear Fatigue Performance of Scarf Repaired Honeycomb Sandwich Structure
Authors: Hao Lei , Gang Qingyong , Wang Xuan , Wang Kuikui , Zheng Yimei 
Published: January 2024

Abstract
The shear static and shear fatigue tests of the honeycomb sandwich composite were carried out to study the effects of three different repair methods on shear fatigue performance: the unilateral panel scarf repair, the unilateral panel and core scarf repair, and the bilateral panel and core scarf repair. The stress ratio R=0.1 was selected. The results show that the failure mode of the honeycomb sandwich structure is the destruction of the honeycomb core. The structure is torn into two halves from the core, and the core tends to squeeze to one side. There is no debonding between the panel and the core, and no delamination in the panel. The static strength, fatigue limit, fatigue life and residual strength of the specimens are significantly decreased by the scarf repair. The rank of reduction from most to least is: the unilateral panel scarf repair, the bilateral panel and core scarf repair, and the unilateral panel and core scarf repair.And the latter two are remarkably similar.
Experimental Study on Effect of Cryogenic Treatment on Cutting Force of Titanium Alloy
Authors: Hua Qinglin , Liu Dong 
Published: January 2024

Abstract
Three titanium alloy materials TA7, TB6 and TC4 were selected, and three titanium alloys with different phases were placed in liquid nitrogen at -196°C for cryogenic treatment, and the change of the cutting performance of titanium alloy samples before and after cryogenic treatment was studied.Six speed combinations of 30m/min, 40m/min, 50m/min, 60m/min, 70m/min and 80m/min were selected to carry out cutting tests.The cutting experiments show that the cutting performance of TA7, TB6 and TC4 titanium alloys has been significantly improved by cryogenic treatment.At different cutting speeds, the cutting force was compared. After cryogenic treatment of three titanium alloy materials, the cutting force was reduced in machining.After cryotreatment, the cutting performance of TB6 was significantly improved, while that of TA7 was relatively low. Among them, TB6 showed the greatest improvement, followed by TA7 and TC4.The three titanium alloys without cryogenic treatment have a cutting speed of 50m/min at maximum cutting force.The maximum cutting force speed of cryogenic titanium alloy is 40m/min.