bluuebunny/crossref_metadata_2025_split huggingface dataset:
The spatial spillover effect of financial growth on high-quality development: Evidence from Yellow River Basin in China
Authors: Zhang Zhenhua , Hua Chao , Jiang Marshall S. , Miao Jianjun 
Published: June 2024

AbstractRiver basin cities are areas with remarkable conflicts between the human activity and the ecological environment. They are also important targets for policy implementation of sustainable and high-quality development (HD) in various countries around the world. This article exploits the panel data of 99 cities located in the Yellow River Basin (YRB) from 2006 to 2019 to empirically analyze the spatial effect of financial growth on HD. Spatial weights participated econometric models are utilized to analyze this spatial effect. Empirical results reveal that: (1) the HD in the YRB shows a strong positive spatial autocorrelation. (2) Financial growth exerts an N-shaped curve effect on the HD from a long-term perspective. When this influence spills out to the surroundings, it exhibits an inverted U-shaped characteristic. (3) Green innovation can be an important intermediary factor in the influence of financial growth on HD. (4) The influence of financial growth on HD appears stronger in regions with higher economic levels, where N-shaped effects can be transmitted to the surrounding regions. However, the backward economic development in low-economy regions prevents the spatial spillover of N-shaped effects. This study can be instrumental for countries to formulate financial policies that aim to promote HD in river basin cities.
Prediction of photodynamics of 200 nm excited cyclobutanone with linear response electronic structure and ab initio multiple spawning
Authors: Hait Diptarka , Lahana Dean , Fajen O. Jonathan , Paz Amiel S. P. , Unzueta Pablo A. , Rana Bhaskar , Lu Lixin , Wang Yuanheng , Kjønstad Eirik F. , Koch Henrik , Martínez Todd J. 
Published: June 2024

Simulations of photochemical reaction dynamics have been a challenge to the theoretical chemistry community for some time. In an effort to determine the predictive character of current approaches, we predict the results of an upcoming ultrafast diffraction experiment on the photodynamics of cyclobutanone after excitation to the lowest lying Rydberg state (S2). A picosecond of nonadiabatic dynamics is described with ab initio multiple spawning. We use both time dependent density functional theory (TDDFT) and equation-of-motion coupled cluster singles and doubles (EOM-CCSD) theory for the underlying electronic structure theory. We find that the lifetime of the S2 state is more than a picosecond (with both TDDFT and EOM-CCSD). The predicted ultrafast electron diffraction spectrum exhibits numerous structural features, but weak time dependence over the course of the simulations.
Ultrafast excited state intramolecular proton transfer and isomerization of long-chain linked Schiff bases
Authors: Wang Ye , Wang Dongdong , Hu Xiao , Zhang Song 
Published: June 2024

The ultrafast proton transfer and the following dynamics for aromatic Schiff bases N,N′-bis(salicylidene)ethylenediamine (salen) and N,N′-bis(salicylidene)-1,4-butylenediamine (salbn) were investigated with experimental and theoretical methods. A dual emission property with a large Stokes shift in salen and salbn indicates that excited state intramolecular proton transfer occurs with photoexcitation. An efficient single proton transfer was confirmed within 200 fs for both molecules. Subsequently, a fast twisted motion of the keto moiety carries cis-keto to a relaxed stable geometry in the S1 state. Following the twisted motion, the phenol ring at keto moiety further rotates to a conical intersection with the ground state and a cis–trans isomerization occurs. The isomerization rate is high, which dominates the competition with the radiative transition, resulting in weak emission intensity. It is confirmed that the length of alkyl chain affects the direction of phenol ring twisting and rotation during the whole subsequent relaxation of excited cis-keto tautomer. Compared with polar solvent acetonitrile, the barrier of isomerization is higher and the hydrogen bond on keto moiety is stronger in nonpolar solvent toluene. It makes fluorescence radiation channels competing with isomerism more likely to occur, contributing to the observed difference of enol/keto emission ratios of salen and salbn in toluene and acetonitrile.
Third density and acoustic virial coefficients of helium isotopologues from ab initio calculations
Authors: Binosi Daniele , Garberoglio Giovanni , Harvey Allan H. 
Published: June 2024

Improved two-body and three-body potentials for helium have been used to calculate from first principles the third density and acoustic virial coefficients for both 4He and 3He. For the third density virial coefficient C(T), uncertainties have been reduced by a factor of 4–5 compared to the previous state of the art; the accuracy of first-principles C(T) now exceeds that of the best experiments by more than two orders of magnitude. The range of calculations has been extended to temperatures as low as 0.5 K. For the third acoustic virial coefficient γa(T), we applied the Schlessinger point method, which can calculate γa and its uncertainty based on the C(T) data, overcoming some limitations of direct path-integral calculation. The resulting γa are calculated at temperatures down to 0.5 K; they are consistent with available experimental data but have much smaller uncertainties. The first-principles data presented here will enable improvement of primary temperature and pressure metrology based on gas properties.
Perpendicular magnetic anisotropy of Cr/CoFeB/MgO modulated by MgO thickness
Authors: Guo Qixun , Huang Yiya , Li Jialiang , Wang Mengjie , Yang Nan , Wang Kun , Cui Chuanyu , Xu Xiulan , Teng Jiao , Zhu Tao , Yu Guanghua 
Published: June 2024

Abstract
The dependence of perpendicular magnetic anisotropy (PMA) on the MgO thickness in Cr/CoFeB/MgO/Ta films has been experimentally investigated. A clear PMA is observed in the as-deposited samples with 1.8 nm MgO while no as-deposited PMA is shown in those with 4.0 nm MgO. This may be attributed to the moderate oxidation degree of CoFeB and larger interfacial anisotropy energy density K
i to overcome the volume magnetic anisotropy and demagnetization field. On the contrary, samples with 4.0 nm MgO demonstrate PMA only after annealing, which might be due to the oxygen and boron diffusion during the annealing process. These results would provide a method to optimize the design of CoFeB/MgO structures on 3d metals for future applications in perpendicular magnetic devices.
Magnetic relaxation between ferromagnetic and helix spin configurations in holmium films
Authors: Morgunov Roman B , Kashin Sergey N , Kunitsyna Ekaterina I , Talantsev Artem D , Chernov Aleksander I 
Published: June 2024

Abstract
Multiple noncollinear spin structures and transitions between them initiated by field and temperature have attracted attention due to the extraordinary coexistence of complicated spin phases in Ho. We explore the magnetic relaxation dynamics within thin films undergoing transitions between ferromagnetic (FM) and helix states. When measuring susceptibility in a relatively high frequency range (∼100–1500 Hz) and magnetic viscosity at lower frequency (∼0.01 Hz), we focus on 400 nm thick Ho film. Notably, sharp variations in the real and imaginary components of magnetic susceptibility are discerned during the FM – Helix transition, occurring at temperatures between 15 and 30 K. Hysteresis effects in the magnetic susceptibility components are identified during cyclic variations in the external field, indicating a relatively rapid process with a timescale of approximately 10 ms accompanying the FM – Helix transition. The slow relaxation process is also found to exhibit sensitivity to this transition. Furthermore, the field dependence of magnetic viscosity displays a marked decline at the FM – Helix transition. The research methodologies proposed for the investigation of relaxation processes in materials with multiphase spin structures are deemed universally applicable and offer insights into transitions between spin states in materials manifesting non collinear spin structures.
Comparison of lattice thermal conductivity using ab-initio DFT, machine learning interatomic potentials, and temperature dependent effective potential: a case study of hexagonal BN and BP bilayer
Authors: Minhas Harpriya , Majumdar Arnab , Pathak Biswarup 
Published: June 2024

Abstract
Discovering high thermal conductivity materials is essential for various practical applications, particularly in electronic cooling. The significance of two-dimensional (2D) materials lies in their unique properties that emerge due to their reduced dimensionality, making them highly promising for a wide range of applications. Hexagonal boron nitride (BN), both monolayer and bilayer forms, has garnered attention for its fascinating properties. In this work, we focus on bilayer boron phosphide (BP), which is isostructural to its BN analogue. The lattice thermal conductivity of both bilayer BN and BP have been calculated using ab-initio density functional theory, machine learning with the moment tensor potential method, and the temperature-dependent effective-potential method (TDEP). The TDEP approach gives more accurate results for both BN and BP materials. The lattice thermal conductivity of bilayer BP is lower than that of bilayer BN at room temperature, attributed to increased phonon anharmonicity. This study highlights the importance of understanding phonon scattering mechanisms in determining the thermal conductivity of 2D materials, contributing to the broader understanding and potential applications of these materials in future technologies.
Doped SnO2 thin films fabricated at low temperature by atomic layer deposition with a precise incorporation of niobium atoms
Authors: Gesesse Getaneh Diress , Coutancier Damien , Katrib Mirella Al , Donsanti Frédérique , Bouttemy Muriel , Schneider Nathanaelle 
Published: June 2024

Abstract
Nb-doped SnO2 (NTO) thin films were synthesized by atomic layer deposition technique at low temperature (100 °C). For an efficient incorporation of the Nb atoms, i.e. fine control of their amount and distribution, various supercycle ratios and precursor pulse sequences were explored. The thin film growth process studied by in-situ QCM revealed that the Nb incorporation is highly impacted by the surface nature as well as the amount of species available at the surface. This was confirmed by the actual concentration of the Nb atom incorporated inside the thin film as determined by XPS. Highly transparent thin films which transmit more than 95% of the AM1.5 global solar irradiance over a wide spectral range (300–1000 nm) were obtained. In addition, the Nb atoms influenced the optical band gap, conduction band, and valence band levels. While SnO2 thin film were too resistive, films tuned to conductive nature upon Nb incorporation with controlled concentration. Optimal incorporation level was found to be ⩽1 at.% of Nb, and carrier concentration reached up 2.5 × 1018 cm−3 for the as-deposited thin films. As a result, the high optical transparency accompanied with tuned electrical property of NTO thin films fabricated by ALD at low temperature paves the way for their integration into temperature-sensitive, nanostructured optoelectrical devices.
Design strategies and systematic analysis of GaN vertical MPS diodes with T-shaped shielding rings
Authors: Wang Heng , Chen Sihao , Chen Hang , Liu Chao 
Published: June 2024

Abstract
We report gallium nitride (GaN) vertical merged pn-Schottky (MPS) diodes with T-shaped p-GaN shielding rings (SRs). The embedded T-shaped SR features an overlapped depletion region by the lateral and vertical p–n junctions under reverse bias condition, which can effectively enhance the charge coupling effect and homogenize the 2D electric field distribution. In the meantime, the incorporation of the T-shaped SRs can minimize unnecessary depletion of the vertical conduction channel and guarantee a decent current spreading through the drift region. The impact of the key design parameters on the reverse breakdown and forward conduction performance are investigated systematically. We found that the doping concentration and the geomatical shape of the T-shaped p-GaN SRs are closed related to the electric field distribution and forward current conduction behavior, which determines the reverse breakdown and forward conduction performance. With optimum design parameters of the T-shaped SRs, the breakdown voltage of the MPS diodes features a dramatic improvement to 2749 V from 1123 V in conventional MPS diodes. The results can provide a design strategy for high performance vertical GaN power diodes towards high-power and high-frequency applications.
A spray-cooling based antagonistic SMA actuator (SCASA) with low resistance consumption and high driving frequency
Authors: Zhang Lei , Jin Hu , Ouyang Yiming , Cheng Wenlong , Li Weihua , Zhang Shiwu 
Published: June 2024

Abstract
Owing to the large strain output and high power-to-weight ratio, using temperature-induced shape memory alloy (SMA) springs in the form of antagonistic actuators offers the opportunity to develop simple, lightweight, and multi-mode robotic systems. Currently, the capabilities and deep application of these robotic systems are hindered by the relatively large resistance consumption and limited driving frequency of the antagonistic SMA actuators, primarily attributed to the cooling rate of SMA. In this paper, a spray-cooling based antagonistic SMA actuator (SCASA) was proposed, aiming to address the existing challenges in antagonistic SMA actuators. Theoretical modeling of the SCASA was comprehensively investigated. Experimental findings highlight the superior cooling efficacy of the spray-cooling method, attaining a cooling rate surpassing 100 °C per second for a single SMA spring. Using the spray-cooling based method, the driving frequency of a single SMA spring is approximately twice that of the forced-air cooling method. Experimental results also demonstrate the superior performance of the SCASA using the spray-cooling method, resulting in a reduction of approximately 50% in resistance consumption and an increase of approximately 40% in driving frequency compared to the forced-air method. This work elucidates the promising application prospects of the spray-cooling method in SMA actuators.
Comparative calculations of trapped field and trapped magnetic flux with different multi-pulse magnetization methods for a bulk high-temperature superconductor
Authors: Yang Yong , Deng Guolong 
Published: June 2024

Abstract
Bulk high-temperature superconductors (HTSs) can trap high magnetic field and are potentially useful for a variety of applications as pseudo-permanent magnets. The pulsed field magnetization (PFM) for bulk HTSs is cost effective and flexible in application compared with quasi-static field cooling and zero field cooling techniques. Many PFM methods have been proposed in many studies to achieve the excellent magnetization performances such as high trapped field and large trapped magnetic flux. In order to clarify the magnetization characteristics of bulk HTSs using different typical PFM methods, we comparatively analyze several typical PFM methods using a simulation model based on the H-formulation combining the thermal conductivity equation. The electromagnetic and thermal behaviors during the magnetization of a bulk HTS with different PFM methods are numerically achieved using the solenoid-type coil to magnetize the bulk. The calculations show that multi-pulse magnetization methods can effectively enhance the trapped field and trapped magnetic flux of the bulk, and different multi-pulse magnetization methods have different efficiencies enhancing these performances. Among all considered PFM methods in the study, the combination method of modified multi-pulse technique with step-wise cooling and iteratively magnetizing pulsed-field method with reducing amplitude has the largest improvement for the trapped magnetic field and the trapped flux simultaneously.
Topological boundary modes in nonlinear dynamics with chiral symmetry
Authors: Zhou Di 
Published: June 2024

Abstract
Particle-hole symmetry and chiral symmetry play a pivotal role in multiple areas of physics, yet they remain unstudied in systems with nonlinear interactions whose nonlinear normal modes do not exhibit

U
(
1
)

-gauge symmetry. In this work, we establish particle-hole symmetry and chiral symmetry in such systems. Chiral symmetry ensures the quantization of the Berry phase of nonlinear normal modes and categorizes the topological phases of nonlinear dynamics. We show topologically protected static boundary modes in chiral-symmetric nonlinear systems. Furthermore, we demonstrate amplitude-induced nonlinear topological phase transition in chiral-symmetric nonlinear dynamics. Our theoretical framework extends particle-hole and chiral symmetries to nonlinear dynamics, whose nonlinear modes do not necessarily yield

U
(
1
)

-gauge symmetry.
Diamond-based electron emission: Structure, properties and mechanisms
Authors: Gu 顾 Liang-Xue 梁雪 , Yang 杨 Kai 凯 , Teng 滕 Yan 妍 , Zhao 赵 Wei-Kang 伟康 , Zhao 赵 Geng-You 耕右 , Fan 凡 Kang-Kang 康康 , Feng 冯 Bo 博 , Zhang 张 Rong 荣 , Zheng 郑 You-Dou 有炓 , Ye 叶 Jian-Dong 建东 , Zhu 朱 Shun-Ming 顺明 , Tang 汤 Kun 琨 , Gu 顾 Shu-Lin 书林 
Published: June 2024

Abstract
Diamond has an ultrawide bandgap with excellent physical properties, such as high critical electric field, excellent thermal conductivity, high carrier mobility, etc. Diamond with a hydrogen-terminated (H-terminated) surface has a negative electron affinity (NEA) and can easily produce surface electrons from valence or trapped electrons via optical absorption, thermal heating energy or carrier transport in a PN junction. The NEA of the H-terminated surface enables surface electrons to emit with high efficiency into the vacuum without encountering additional barriers and promotes further development and application of diamond-based emitting devices. This article reviews the electron emission properties of H-terminated diamond surfaces exhibiting NEA characteristics. The electron emission is induced by different physical mechanisms. Recent advancements in electron-emitting devices based on diamond are also summarized. Finally, the current challenges and future development opportunities are discussed to further develop the relevant applications of diamond-based electron-emitting devices.
Noise-induced phase transition in the Vicsek model through eigen microstate methodology
Authors: Jia 贾 Yongnan 永楠 , Han 韩 Jiali 佳丽 , Li 李 Qing 擎 
Published: June 2024

Abstract
This paper presents a comprehensive framework for analyzing phase transitions in collective models such as the Vicsek model under various noise types. The Vicsek model, focusing on understanding the collective behaviors of social animals, is known due to its discontinuous phase transitions under vector noise. However, its behavior under scalar noise remains less conclusive. Renowned for its efficacy in the analysis of complex systems under both equilibrium and non-equilibrium states, the eigen microstate method is employed here for a quantitative examination of the phase transitions in the Vicsek model under both vector and scalar noises. The study finds that the Vicsek model exhibits discontinuous phase transitions regardless of noise type. Furthermore, the dichotomy method is utilized to identify the critical points for these phase transitions. A significant finding is the observed increase in the critical point for discontinuous phase transitions with escalation of population density.
Development and manufacturing of beryllium-armoring ITER enhanced heat flux FW toward series production in China
Authors: Chen J.M. , Wang P.H. , Zhou Y. , Li Q. , Li J.L. , Wu J. , Du J. , Yang B. , Zhu X.B. , Gao H. , Hu D. , Chen Y.Y. , Wang Q.M. , Liu Z.H. , Wang K. , Liu S. , Bao L.M. , Hunt R. 
Published: June 2024

Abstract
ITER’s enhanced heat flux (EHF) first wall (FW) provides thermal shielding to the other components behind it and limits its plasma boundary, consequently bearing high surface heat loads up to 4.7 MW m−2. China developed the EHF FW technologies in steady stages by making small mock-ups, semi-prototypes and a full-scale prototype (FSP), working toward series production at the Southwestern Institute of Physics. All the key technologies for bimetallic diffusion bonding, welding and assembly have been fully qualified. The Be armor tile size effects on thermal-fatigue performance have been evaluated using a pulsed high heat flux test with an EMS-400 electron beam facility. It was found that both the Be/CuCrZr bonding and its thermal-fatigue life are highly dependent on the tile size, and 12 × 12 mm2 Be tiles are acceptable for the required performance, either as individual tiles or in castellation by cutting larger ones. Small-scale mock-ups with such Be tiles survived 16 000 thermal cycles at 4.7 MW m−2, while EHF FW fingers with 16 × 16 mm2 Be tiles demonstrated unstable performance. In contrast, only BE tiles larger than 24 × 12 mm2 showed reliable diffusion bonding with the CuCrZr heat sink by hot isostatic pressing and consequently should be castellated into smaller ones. The manufacturing of the FSP finger goes through complex thermal cycles, using CuCrZr alloys in age-strengthening plus cold-rolling states, enabling it to maintain its tensile strength to the level of 285 MPa and its mean grain size less than 100 µm. The pipe welding for finger pairing and its assembly with the central beam are demonstrated, including enabling welding to be carried out twice for repair in a narrow space. The FSP showed good finger alignment, dimensional control and reliable vacuum tightness without any blockage of cooling channels.
Application of Choline Chloride - Ethylene Glycol Deep Eutectic Solvent for the Extraction of Monocylclic Aromatic Hydrocarbon Contaminants from Soil
Authors: Haruna Almustapha Ismail , Sani Gano Zaharaddeen , Umar Ahmed Omar , Yusuf Atta Abdulazeez , Mohammed Shuwa Suleiman , Yakubu Jibril Baba , Adamu Yahaya Sulaiman 
Published: June 2024

Abstract
Monocyclic aromatic hydrocarbons like Benzene, toluene, ethylbenzene and xylene (BTEX) are among environmental pollutants that are considered among chemicals of concern. They are often found in industrial effluents, which when discharged into farmlands end up contaminating the soils. Such happenings warrant the remediation of the soil for environmental sustainability. Solvent extraction, prominent among the techniques employed for this remediation, is limited by the type of solvent used, as volatile organic solvents end up producing secondary pollutants. Various kinds of green solvents like Ionic Liquids (ILs) and Deep Eutectic Solvents (DESs) have been used in this technique as replacements for the conventional ones. In this study, DES made from choline chloride and ethylene glycol in the ratio of 1:2 was synthesized, characterized and used for the remediation of soils contaminated with monocyclic aromatic hydrocarbons (BTEX). Response surface methodology was employed to model and optimize the extraction process. Extraction efficiencies of 76.25, 79.04, 81.93 and 78.66% were obtained for benzene, toluene, ethylbenzene and xylene in a single stage extraction at optimum condition of 45 minutes, 0.841 and 440 rpm for extraction time, solvent mass fraction and mixing rate respectively. Further studies on the solvent regeneration and reuse were conducted. The findings showed that the solvent has capacity to perform effectively in two (2) successive extraction cycles without regeneration, and can undergo up to five (5) cycles upon regeneration without significant loss in its extracting ability. These studies show the possibility of remediating soils contaminated with BTEX using DES under mild extraction conditions.