bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamics of the Cl + CH3CN reaction on an automatically-developed full-dimensional ab initio potential energy surface
Authors: Tóth Petra , Szűcs Tímea , Győri Tibor , Czakó Gábor 
Published: August 2024

A full-dimensional analytical potential energy surface (PES) is developed for the Cl + CH3CN reaction following our previous work on the benchmark ab initio characterization of the stationary points. The spin–orbit-corrected PES is constructed using the Robosurfer program and a fifth-order permutationally invariant polynomial method for fitting the high-accuracy energy points determined by a ManyHF-based coupled-cluster/triple-zeta-quality composite method. Quasi-classical trajectory simulations are performed at six collision energies between 10 and 60 kcal mol−1. Multiple low-probability product channels are found, including isomerization to isonitrile (CH3NC), but out of the eight possible channels, only the H-abstraction has significant reaction probability; thus, detailed dynamics studies are carried out only for this reaction. The cross sections and opacity functions show that the probability of the H-abstraction reaction increases with increasing collision energy (Ecoll). Scattering angle, initial attack angle, and product relative translational energy distributions indicate that the mechanism changes with the collision energy from indirect/rebound to direct stripping. The distribution of initial attack angles shows a clear preference for methyl group attack but with different angles at different Ecoll values. Post-reaction energy distributions show that the energy transfer is biased toward the products’ relative translational energy instead of their internal energy. Rotational and vibrational energy have about the same amount of contribution to the internal energy in the case of both products (HCl and CH2CN), i.e., both of them are formed with high rotational excitations. HCl is produced mostly in the ground vibrational state, while a notable fraction of CH2CN is formed with vibrational excitation.
Efficient real space formalism for hybrid density functionals
Authors: Jing Xin , Suryanarayana Phanish 
Published: August 2024

We present an efficient real space formalism for hybrid exchange-correlation functionals in generalized Kohn–Sham density functional theory (DFT). In particular, we develop an efficient representation for any function of the real space finite-difference Laplacian matrix by leveraging its Kronecker product structure, thereby enabling the time to solution of associated linear systems to be highly competitive with the fast Fourier transform scheme while not imposing any restrictions on the boundary conditions. We implement this formalism for both the unscreened and range-separated variants of hybrid functionals. We verify its accuracy and efficiency through comparisons with established planewave codes for isolated as well as bulk systems. In particular, we demonstrate up to an order-of-magnitude speedup in time to solution for the real space method. We also apply the framework to study the structure of liquid water using ab initio molecular dynamics, where we find good agreement with the literature. Overall, the current formalism provides an avenue for efficient real-space DFT calculations with hybrid density functionals.
Fabrication of ultra-low expansion glass based double paddle oscillator
Authors: Jose Sabitha Ann , Atwa Yahya , Iqbal Faisal , McNeill David , Shakeel Hamza 
Published: August 2024

Abstract
Ultra-low expansion (ULE) glasses, with their excellent material properties like low thermal expansion coefficient (0.5 ppm K−1), are highly suitable for manufacturing micromechanical resonators. However, the lack of suitable microfabrication processes primarily limits the use of ULE glasses to macroscopic applications. This paper describes a detailed micro fabrication technique for producing double paddle oscillators (DPOs) using ULE glass substrates. We used a combination of low-pressure chemical vapor deposition (LPCVD), lithography, and wet etching techniques to manufacture millimeter sized mechanical oscillator with a thickness of 500 μm. We utilized a thick layer of LPCVD polysilicon (∼2.5 μm) as a hard mask for double side etching of thick ULE substrate. We were able to successfully identify different resonant modes of the DPOs using both electrostatic and optical detection methods. A laser Doppler vibrometer system was utilized to confirm different simulated resonant modes. Additionally, quality factor was extracted for different modes from ring down measurements for the first time in ULE based DPO.
Dispersion compensation design of high-density stacking RFSS absorbers for wideband applications
Authors: Luo Zhinan , Ding Xiaoxiao , Yang Jie , Wu Yuhan , Wang Bichao , Miao Ling , Bie Shaowei , Jiang Jianjun 
Published: August 2024

Abstract
A dispersion compensation design absorber realized by high-density stacking resistive frequency selective surface (RFSS) is proposed for wideband applications. Firstly, the quantitative relationship between the equivalent impedance of RFSS and the permittivity of the effective media is constructed with the help of the transmission matrix method. The dispersion regulation of permittivity is achieved by changing the pattern and the square resistance of RFSS. In terms of absorber design, a uniform absorber with dispersion manipulation is developed as a precursor absorber. The uniform absorber has an absorption performance better than −8.5 dB above 2 GHz at normal incidence. The loss mechanism is analyzed in detail by electric field distribution and surface power loss density distribution, indicating that the uniform design cannot achieve thickness saving when extending to low frequency. Therefore, a dispersion compensation design absorber is proposed to extend −10 dB bandwidth to 1.64–28.8 GHz. Experiment results agree well with the simulation results, validating the analytic methods and design principles.
Tailoring thermal transport and confinement effect of GaN/Si3N4 nanowires utilizing core–shell architecture
Authors: Yang Yuting , Yuan Kunpeng , Wang Zhaoliang 
Published: August 2024

Abstract
The thermal transport properties of nanowires (NWs) can be significantly influenced by the implementation of a core–shell structure, which introduces interface scattering and phonon localization effects, opening avenues for novel applications. In this paper, we use the method of non-equilibrium molecular dynamics to simulate the effects of system temperature, cross-sectional width, and nanopillar interface on the thermal transport of GaN/Si3N4 core–shell NWs. The thermal transport process of phonons in core–shell NWs is studied by calculating the vibrational density of states, phonon participation rate, and dispersion curve. The results show that the core–shell NWs characterized by smooth interfaces exhibit a 17.4% decrease in thermal conductivity (TC) at room temperature when contrasted with pristine GaN NWs. Furthermore, the TC of GaN/Si3N4 core–shell NWs can be further reduced by adding nanopillars at the interface. Due to resonance effect, thus effectively regulating the thermal transport. The presence of nanopillars increases phonon–surface scattering intensity at low-frequency and modifies phonon dispersion to decrease the group velocity. In addition, the hybridization of phonon modes between those of the nanopillars and the Si3N4 shell gives rise to numerous dispersionless resonance phonon modes that span the entire phonon spectrum. This research delves into the effects of nanopillars and interfaces on thermal transport, providing important guidance for understanding confinement effects and establishing a robust theoretical basis for the regulation of thermal transport.
Exploring the potential of 3D printing for shape memory alloys: a critical review
Authors: Ahmad Shadab , Hashmi Abdul Wahab , Iqbal Faiz , Rab Shanay , Tian Yebing 
Published: August 2024

Abstract
Shape memory alloys (SMAs) have garnered substantial attention due to their remarkable properties and diverse applications with 3D printing techniques. The present work comprehensively reviews 3D printing applied to various SMAs. The paper examines different 3D printing techniques for SMAs and discusses the process parameters crucial for printability. The potential of 3D printing SMAs lies in the ability to create complex geometries and customized designs that are unattainable through conventional manufacturing methods. Thus, 3D printed SMAs are used across diverse fields, including biomedicine, aerospace, engineering, and consumer goods. While recognizing the notable progress achieved, the review addresses ongoing challenges such as attaining consistent microstructures, post-processing and cost-effective production. It also highlights future prospects, including the development of new SMAs compositions, and expanded applications in various other fields. As a result, the review offers a succinct and comprehensive report on SMAs using 3D printing, which could serve as a useful resource for scientists, engineers, researchers, and industry in their future work.
Effects of size and shape of hole defects on mechanical properties of biphenylene: a molecular dynamics study
Authors: Xiao Shuoyang , Hao Jiannan , Shi Tan , Jin Jianfeng , Wu Bin , Peng Qing 
Published: August 2024

Abstract
The distinctive multi-ring structure and remarkable electrical characteristics of biphenylene render it a material of considerable interest, notably for its prospective utilization as an anode material in lithium-ion batteries. However, understanding the mechanical traits of biphenylene is essential for its application, particularly due to the volumetric fluctuations resulting from lithium ion insertion and extraction during charging and discharging cycles. In this regard, this study investigates the performance of pristine biphenylene and materials embedded with various types of hole defects under uniaxial tension utilizing molecular dynamics simulations. Specifically, from the stress‒strain curves, we obtained key mechanical properties, including toughness, strength, Young’s modulus and fracture strain. It was observed that various near-circular hole (including circular, square, hexagonal, and octagonal) defects result in remarkably similar properties. A more quantitative scaling analysis revealed that, in comparison with the exact shape of the defect, the area of the defect is more critical for determining the mechanical properties of biphenylene. Our finding might be beneficial to the defect engineering of two-dimensional materials.
A linear compensation method for inference accuracy improvement of memristive in-memory computing
Authors: Dai Yuehua , Wang Zeqing , Feng Zhe , Zou Jianxun , Guo Wenbin , Tan Su , Yu Ruihan , Hu Yang , Qian Zhibin , Hu Junliang , Xu Zuyu , Zhu Yunlai , Wu Zuheng 
Published: August 2024

Abstract
Memristive computing system (MCS), with the feature of in-memory computing capability, for artificial neural networks (ANNs) deployment showing low power and massive parallelism, is a promising alternative for traditional Von-Neumann architecture computing system. However, because of the various non-idealities of both peripheral circuits and memristor array, the performance of the practical MCS tends to be significantly reduced. In this work, a linear compensation method (LCM) is proposed for the performance improvement of MCS under the effect of non-idealities. By considering the effects of various non-ideal states in the MCS as a whole, the output error of the MCS under different conditions is investigated. Then, a mathematic model for the output error is established based on the experimental data. Furthermore, the MCS is researched at the physical circuit level as well, in order to analyze the specific way in which the non-idealities affect the output current. Finally, based on the established mathematical model, the LCM output current is compensated in real time to improve the system performance. The effectiveness of LCM is verified and showing outstanding performance in the residual neural network-34 network architecture, which is easily affected by the non-idealities in hardware. The proposed LCM can be naturally integrated into the operation processes of MCS, paving the way for optimizing the deployment on generic ANN hardware based on the memristor.
The adsorption performance of harmful gas (CO, SO) on doped graphene: a first-principle study
Authors: Liu Yufeng , Shen Yang , Liu Guanpeng , Tu Wenbing , Ni Jiaming 
Published: August 2024

Abstract
The adsorption of gas molecules (CO, SO) by different atoms (Cu, Fe, Pd, Pt, B, N, P, S) doped graphene has been investigated in terms of adsorption energies, charge transfer, and density of states based on the density functional theory. The Result that the metal atoms enhance the interaction of graphene with the above gas molecules much more than the non-metal atoms, and it is due to this strong interaction that the gas molecules (CO, SO) chemisorb on graphene doped with metal atoms. Meanwhile, the metal atom doped graphene is more sensitive to SO molecules. Moreover, the charge transfer of CO/Pd–G is 0.056e, and the adsorption energy is −6.386 eV, and there is a very large deformation of Pt–G after adsorption of SO and the reaction is very violent, with an adsorption energy up to −7.922 eV and a charge transfer up to 0.537e, which is the highest of all systems. Therefore, we believe that Pt–G is suitable for the detection of the SO while Pd–G is suitable for the detection of the CO. In addition, combined with the nature of the work function, we believe that metal-doped graphene has the potential to be a highly sensitive irreversible sensor.
Structural health monitoring for 3D-printed civil infrastructures: a review of challenges, applications and future directions
Authors: Parida Lukesh , Moharana Sumedha 
Published: August 2024

Abstract
The integration of 3D printed constructions into civil projects has created new opportunities for economically efficient construction. However, preserving the long-term structural integrity of 3D-printed structures poses considerable challenges. This study covers the importance of structural health monitoring (SHM) and deployment of sensors for condition monitoring of 3D-printed civil infrastructure. It explores a wide range of sensors that might be used for continual evaluation and assessment of structural efficiency and the challenges related to SHM in these components. The report provides cost benefit analysis and case studies describing effective sensor installations in 3D-printed structures, demonstrating the ability of the technology to enhance the safety and integrity of infrastructure systems. It also identifies potential challenges and issues that must be resolved before sensor-based SHM can be successfully used in 3D-printed civil structures. The research emphasizes the potential of maintenance planning and decision support systems for optimizing maintenance schedules, reducing downtime, and increasing cost-effectiveness. This research is critical for academics, engineers, and professionals using sensors for 3D-printed structural systems.
Active acoustic metamaterials with on-demand bulk modulus and full mass density tensor
Authors: Kovacevich Dylan A , Popa Bogdan-Ioan 
Published: August 2024

Abstract
Active metamaterials address fundamental limitations of passive media and have widely been recognized as necessary in numerous compelling applications such as cloaking and extreme noise absorption. However, most practical devices of interest have yet to be realized due to the lack of a suitable strategy for implementing bulk active metamaterials—those that involve interacting cells and functionality beyond one dimension. Here, we present such an active acoustic metamaterial design with bulk modulus and anisotropic mass density that can be independently programmed over wide value ranges. We demonstrate this ability experimentally in several examples, targeting acoustic properties that are hard to access otherwise, such as a bulk modulus significantly smaller than air, strong mass density anisotropy, and complex bulk modulus and mass density for high reflectionless sound absorption. This work enables the transition of active acoustic metamaterials from isolated proof-of-concept demonstrations to versatile bulk materials.
Bipolar topological spin diode and topological spin transistor in finite size quantum spin Hall insulators
Authors: Luo Kun , Chen Xi-Rong 
Published: August 2024

Abstract
The miniaturization and stability of electronic devices are becoming increasingly important today. We attempt to provide the theoretical support for designing spintronic devices by numerically investigating spin transport in finite size quantum spin Hall insulators (QSHI) under a perpendicular weak magnetic field. By modifying magnetic field strength, we find the gapped spin up and spin down bands are split to realize a half-metal phase which is a promising candidate for designing an efficient spin filter. Moreover, one of the two energy gaps becomes larger and the other smaller due to the weakened or enhanced coupling between two edge states. Here we propose and demonstrate the spin filter based on a finite size QSHI junction under a magnetic field and the polarity can be inverted by a bias voltage or magnetic field. Interestingly, we find a bipolar spin diode effect that only one spin channel is opened and the other spin channel is closed at positive bias, and the opposite spin electron can be transmitted with negative bias. Two spin filters in series can be a spin transistor, the on and off states can be controlled by spin polarization of one spin filter. We show that the topological spin transistor can be controlled by the gate voltage, and it survives in moderate disorder.
SOS decomposition for general Bell inequalities in two qubits systems and its application to quantum randomness
Authors: Zhao Wen-Na , Xiao Youwang , Li Ming , Xu Li , Fei Shao-Ming 
Published: August 2024

Abstract
Bell non-locality is closely related with device independent quantum randomness. In this paper, we present a kind of sum-of-squares (SOS) decomposition for general Bell inequalities in two qubits systems. By using the obtained SOS decomposition, we can then find the measurement operators associated with the maximal violation of considered Bell inequality. We also practice the SOS decomposition method by considering the (generalized) Clauser-Horne-Shimony-Holt (CHSH) Bell inequality, the Elegant Bell inequality, the Gisin inequality and the Chained Bell inequality as examples. The corresponding SOS decompositions and the measurement operators that cause the maximum violation values of these Bell inequalities are derived, which are consistent with previous results. We further discuss the device independent quantum randomness by using the SOS decompositions of Bell inequalities. We take the generalized CHSH inequality with the maximally entangled state and the Werner state that attaining the maximal violations as examples. Exact value or lower bound on the maximal guessing probability using the SOS decomposition are obtained. For Werner state, the lower bound can supply a much precise estimation of quantum randomness when p tends to 1.
Symmetric structures and dynamic analysis of a (2+1)-dimensional generalized Benny-Luke equation
Authors: Sun Jie , Zhao Qiulan , Li Xinyue 
Published: August 2024

Abstract
We study the symmetric structures and dynamic analysis of a (2 + 1)-dimensional generalized Benny-Luke (GBL) equation based on the Lie symmetry method, the GBL equation is an important non-integrable model of water waves. Specifically, we construct multiple exact solutions of the GBL equation and obtain its nonlocally related systems. Firstly, the Lie point symmetries and conservation laws of the GBL equation are computed, and then we get the reduced ordinary differential equation from one of the conservation laws. Multiple methods, for example, the dynamical systems method, the power series method, the homogeneous balancing method and generalized variable separation method, are used to solve the ordinary differential equation and abundant exact solutions of the GBL equation are got. Finally, we extend these exact solutions by discrete symmetries, and give three-dimensional graphs of partial exact solutions. In addition, we construct the nonlocally related PDE systems, which contains the potential systems from the conservation laws and an inverse system from a Lie point symmetry of the GBL equation. These findings reveal the dynamical behavior behind the GBL equation and broaden the range of nonlinear water wave model solutions.
Non-Hermitian quantum walks and non-Markovianity: the coin-position interaction
Authors: Badhani Himanshu , Banerjee Subhashish , Chandrashekar C M 
Published: August 2024

Abstract
A

P
T

-symmetric, non-Hermitian Hamiltonian in the

P
T

-unbroken regime can lead to unitary dynamics under the appropriate choice of the Hilbert space. The Hilbert space is determined by a Hamiltonian-compatible inner product map on the underlying vector space, facilitated by a ‘metric operator’. A more traditional method, however, involves treating the evolution as open system dynamics, and the state is constructed through normalization at each time step. In this work, we present a comparative study of the two methods of constructing the reduced dynamics of a system evolving under a

P
T

-symmetric Hamiltonian. Our system is a one-dimensional quantum walk with the spin and position degrees of freedom forming its two subsystems. We compare the information flow between the subsystems under the two methods. We find that under the metric formalism, a power law decay of the information backflow to the subsystem gives a clear indication of the transition from

P
T

-unbroken to the broken phase. This is unlike the information backflow under the normalized state method. We also note that even though non-Hermiticity models open system dynamics, pseudo-Hermiticity can increase entanglement between the subsystem in the metric Hilbert space, thus indicating that pseudo-Hermiticity cases can be seen as a resource in quantum mechanics.
Nonlinear friction dynamics of water-lubricated bearings under transient shocks considering cavitation and turbulence effects
Authors: Chen Ziqi , Wang Ji , Li Rui , Liu Yujun 
Published: August 2024

Abstract
This study proposes a transient elastohydrodynamic mixed lubrication (EHML) model for water-lubricated bearings (WLBs) that incorporates cavitation and turbulence effects to evaluate the nonlinear friction dynamic performance under transient shock loads. The generalized average Reynolds equation is discretized using the control volume technique (CVM), and the constrained system is solved using the Fischer-Burmeister-Newton-Schur (FBNS) method. The validity of the model is verified by a comparison of experimental data from published literature. On this basis, the effects of cavitation, turbulence, shock load amplitude, direction, time, and rotational speed on WLB nonlinear friction dynamics characteristics are investigated. The results show that cavitation induces hydrodynamic loss under transient shock conditions, significantly increases contact time and load, and exacerbates the hydrodynamic instability phenomenon. In contrast, the turbulence effect effectively reduces frictional contact. The stability of WLBs under transient shock conditions is closely related to the load offset angle. Reducing the load offset angle improves the anti-shock stability of the bearings. Nevertheless, an increase in the amplitude and duration of the shock load may result in a deterioration of the frictional contact behavior. Increasing the rotational speed appropriately favors accelerating the lubrication regime transition and improving WLB’s anti-shock stability. This study provides a reference for enhancing WLB anti-shock performance and optimizing structural design.