bluuebunny/crossref_metadata_2025_split huggingface dataset:
First-principles study of Stone–Wales defects in monolayer and Bernal-stacked hexagonal boron nitride
Authors: Wang Mingyuan , Zhang Quan , Jiang Yun-cai , Hussain Shahid , Liu Guiwu , Wan Neng , Lei Shuang-Ying , Leifer Klaus 
Published: June 2024

Abstract
Recently, Stone–Wales (SW) defects gradually attracted people’s research interest because of their unique properties. The theoretical research indicated that the SW defect in hexagonal boron nitride (h-BN) can lead to new defect levels in bandgap, making h-BN apply in ultraviolet emitters. However, the SW defect is always observed in graphene and rarely observed in h-BN in the experiments. Here, we confirmed the SW defects are not easily formed in h-BN under thermodynamic conditions by first-principles calculations. Specifically, the monolayer h-BN with SW defect (h-BN-SW) has the weak bond strength, dynamic stability and high-temperature thermal stability, facilitating the healing of SW defects under high-temperature conditions and the role of hydrogen. Additionally, we found the SW defect in AB stacked h-BN (AB-h-BN) have good mechanical stability, dynamic stability and thermodynamic stability than h-BN-SW, especially for AB-h-BN-2SW (2SW defects formed in upper and lower layer of AB-h-BN, respectively), which can meet the requirements for its application in electronic devices. Even under thermodynamic conditions, the formation of SW defects is extremely challenging. Electron beam irradiation technology provides a window for the generation of SW defects in h-BN. This offers opportunities for the introduction and control of SW defects, while also creating potential for their application in electronic devices. Moreover, we found that the absorption peak broadens, and a new absorption peak appears with the generation of SW defects, which is mainly induced by the decrease of bandgap and the generation of defect levels. Our research can provide theoretical guidance at atomic scale for designing and applying h-BN with SW defect in the experiments.
The electronic structure, optical property and n-type conductivity for W-doped α-Ga2O3: hybrid functional study
Authors: Chang Jinyan , Kang Sixin , Chen Yu , Fan S W 
Published: June 2024

Abstract
Based on the hybrid functional method, the electronic structure, optical property and electron effective mass of α-Ga2O3, together with the properties for intrinsic and extrinsic defects incorporated into α-Ga2O3 are studied. Obtained results indicate the α-Ga2O3 possesses a wide band gap (5.31 eV), small electron effective mass (0.22 m0) and a high visible light transmittance. The nonstoichiometric α-Ga2O3 is not an excellent n-type semiconductor. To improve the n-type conductivity, the W-doped α-Ga2O3 is studied. We find that W
Ga is a promising n-type defect due to its relatively small ionization energy ϵ(0/+) (0.30 eV). When the equilibrium fabrication method is selected, the WO2 is a promising dopant source. Using the equilibrium fabrication method, the defect complex (V
O+ W
Ga) would be formed, and the ionization energy ϵ(0/+) for defect complex (V
O + W
Ga) would decrease to 0.08 eV, which implies that a great number of free electrons could be induced in the samples. We expect that this work can promote the understanding of the n-type conductivity for α-Ga2O3 and provide significant insights for the development of a transparent n-type semiconductor.
Tunable high-Q resonances based on the asymmetric nanohole array of phase-change material
Authors: Jiang Xin-Yuan , Zhang Yu-Jie , Fang Bin , Zhang Dong-Qin , Pan Gui-Ming , Jin Zhong-Wei , Hong Zhi , Shu Fang-Zhou 
Published: June 2024

Abstract
Dielectric metasurfaces have made great progress over the past decade to enhance light-matter interaction. Recently, dielectric nanohole structures have been employed for the creation of dielectric metasurfaces. However, the optical characteristics of most dielectric nanohole structures remain fixed once they are manufactured. This study investigates the optical properties of Ge2Sb2Te5 (GST) film perforated with a periodic dual nanohole array. The GST dual nanohole array is capable of supporting multiple guided resonances and bound states in the continuum (BICs). By introducing asymmetry in the radius, BICs can be transformed into quasi-BICs with high-Q resonances. The wavelengths of guided resonances and quasi-BICs can be dynamically controlled through the phase transition of GST. Furthermore, modifying the gap allows for the achievement of active high-Q electromagnetically induced transparency, resulting from the interaction between one guided resonance and one quasi-BIC mode. The GST asymmetric nanohole array holds potential for applications in optical modulators, slow-light devices, and nonlinear optical devices.
Parallel processing of sensor signals using deep learning method for aero-engine remaining useful life prediction
Authors: Wang Tianyu , Li Baokui , Fei Qing , Xu Sheng , Ma Zhihao 
Published: June 2024

Abstract
Accurately predicting the remaining useful life of aerospace engines is crucial for enhancing the reliability of aviation equipment. While some methods have taken note of the challenges posed by vast sensor data and complex signal interrelationships, there is still room for improvement in performance. This paper proposes a novel deep learning model that utilizes a parallel structure to independently process inputs from various sensor signals. Each branch in this parallel structure employs a combination of an improved Inception module and a novel feature filtering module as a feature extractor. The improved Inception module boasts a larger perceptual field to ensure the integrity of feature information. The feature filtering module calculates the importance weights of feature information through convenient computation, allowing the network to focus more on feature information without significantly increasing computational complexity. Finally, the feature extractor is combined with a gated recurrent unit module to learn features from sensor signals. Extensive experiments were conducted on the C-MAPSS standard dataset, comparing the proposed method with other state-of-the-art methods. Ablation experiments were performed on the new generation N-CMAPSS standard dataset. The results of the experiments confirm the superiority and rationality of the proposed prediction method.
Anomaly detection method for urban river water quality based on background model prediction using three-dimensional fluorescence
Authors: Zhang Qiuhao , Yu Jie , Shi Jiegen , Xue Fangjia , Hou Dibo , Zhang Guangxin 
Published: June 2024

Abstract
Three-dimensional fluorescence spectroscopy has great potential for detecting water quality anomalies in urban rivers and protecting against organic pollution. However, current detection methods inadequately address critical application scenarios, such as fluctuations in river water background, low concentration of pollutants, and the fluorescence peaks overlap between pollutants and background. In this paper, a fluorescence spectrum feature extraction method which is effective for the above scenarios was proposed. The proposed method involves a sequential process. First, the original spectrum undergoes preprocessing using a novel method. Next, an alternating residual tri-linearization technique is applied to establish a predictive model for river water spectrum changes. Subsequently, the background model is utilized for spectrum decomposition and reconstruction of the test sample. This reconstructed spectrum is then used to derive the residual spectrum by comparison with the original. Finally, frequency domain features are extracted from the residual spectrum to enable classification, while the background model undergoes real-time updates. In the three meaningful scenarios mentioned above, the accuracy of the proposed method for anomaly detection reached 99%, 82%, and 98%, respectively. Our accuracy is higher than several typical benchmark methods.
MKurt-LIA: mechanical fault vibration signal measurement scheme with frequency tracking capability for bearing condition monitoring
Authors: Zhang Meng 
Published: June 2024

Abstract
Monitoring the operational status of rolling bearings is crucial to ensuring the reliable operation of mechanical equipment, and it is considered as an important task of prognostics and health management in mechanical industry. Finding fault pattern directly from vibration signals measured on bearings can be challenging due to strong noise. Lock-in amplifiers (LIAs) can effectively measure the strength of weak fault signals distorted by noise, thus providing insights for fault diagnosis. However, LIAs are sensitive to the reference frequency, and an incorrect reference frequency can render the measurement even meaningless. In this study, a measurement scheme of LIA with the ability to track time-varying fault frequencies is proposed for measuring fault vibration signal components of in-service bearings, termed MKurt-LIA. The MKurt spectrum is employed for searching the local fault frequencies in the time domain, overcoming the negative impact introduced by using theoretical fault characteristic frequencies calculated based on bearing geometry in previous works. Guided by the statements in Guide to the Expression of Uncertainty in Measurement and its supplements, this work demonstrates through the analysis of propagation of distributions that the negative impact of fault frequency deviation on measurement results is significant and cannot be ignored. Experimental results confirm that the MKurt-LIA scheme effectively measures the amplitude of fault frequency components during bearing service, enabling the detection of fault evolution in the early stages where fault characteristics are completely submerged in the time domain waveform. MKurt-LIA scheme fully respects the fact that fault frequency always deviates from theoretical value, and achieves significantly robust performance in assessing in-service bearing’s operation condition.
A non-intrusive volumetric camera calibration system
Authors: Gunady Ian E , Ding Liuyang , Singh Devdigvijay , Alfaro Bryan , Hultmark Marcus , Smits Alexander J 
Published: June 2024

Abstract
When acquiring quantitative data using cameras, calibration is required to establish the mapping relation between the image space and physical space. Calibration targets with known dimensions are often used, with the most popular being physical targets. In setups where physical access is a challenge, using physical targets may not be possible, and so we develop an adaptive non-intrusive calibration target capable of conducting volumetric calibrations in free space. The calibration target is formed by two intersecting laser beams traversed in the test domain. A novel algorithm is presented for accurately finding the beam intersections, even at small crossing angles. The error sources are assessed along with their scaling behavior with respect to key parameters. The performance of the calibration method is evaluated by using it to examine a test object with known dimensions.
Cage-by-cage supramolecular polymerization via panel-decorated triphenylphosphine organic cage
Authors: Mu Gui-Fang , Yang Cuiqin , Wang Yixin , Yan Qiang 
Published: June 2024

Abstract
Significant efforts have been dedicated to designing porous organic cage compounds with geometric complexity and topological diversity. However, the use of these cage molecules as premade building units for constructing infinite cage-based superstructures remains unexplored. Here, we report the use of a panel-decorated phosphine organic cage as a special monomer to achieve supramolecular polymerization, resulting in cage-by-cage noncovalent polymers through the synergy of metal-coordination and intercage π–π dimerization. At a monomer concentration of 122 mM, the average degree of polymerization reaches 17, corresponding to a molecular weight of 26 kDa. The obtained cage-based supramolecular polymers can further hierarchically self-assemble into vesicular morphologies or one-dimensional nanofiber architectures. Selective control over the cosolvents can regulate their structural hierarchy and assembled morphology. This approach paves a new way for the construction of cage-based hierarchical assemblies and materials.
Nontrivial d-electrons driven superconductivity of transition metal diborides
Authors: Wang Yu , Tang Ju-Hong , Xu Hong-Rui , Zhou Guanghui , Ouyang Gang , Deng Hui-Xiong , D’Agosta Roberto , Yang Kaike 
Published: June 2024

Abstract
Leveraging the progress of first-principles modelings in understanding the mechanisms of superconductivity of materials, in this work we investigate the phonon-mediated superconducting properties of transition metal diborides. We report that TaB2 and NbB2 show superconducting transition temperatures as high as 27.0 and 26.0 K at ambient conditions, respectively, comparable with those obtained for CaB2 or MgB2. By mode-by-mode analysis of the electron-phonon-coupling, we reveal that the high superconducting temperature of transition metal diborides is due mainly to the strong coupling between d electrons of the transition metals and the acoustic phonon modes along out-of-plane vibrations. This fact is distinct from that of CaB2 or MgB2, where the superconductivity stems mainly from the boron px
and py
orbitals, which couple strongly to the optical phonon modes dominated by in-plane B atomic vibrations. Further, we find that transition metal diborides present only a superconducting gap at low temperatures, whereas CaB2 or MgB2 are double superconducting gap superconductors. In addition, we investigate the strain effect on the superconducting transition temperatures of diborides, predicting that Tc
can be further enhanced by optimizing the phonon and electronic interactions. This study sheds some light on the exploring high Tc
boron-based superconductor materials.
Lattice imperfections and high-harmonic generation in correlated systems
Authors: Hansen Thomas , Bojer Madsen Lars 
Published: June 2024

Abstract
We study effects of lattice imperfections on high-harmonic generation from correlated systems using the Fermi–Hubbard model. We simulate such imperfections by randomly modifying the chemical potential across the individual lattice sites. We control the degree of electron–electron interaction by varying the Hubbard U. In the limit of vanishing U, this approach results in Anderson localization. For nonvanishing U, we rationalize the spectral observations in terms of qualitative k-space and real-space pictures. When the interaction and imperfection terms are of comparable magnitude, they may balance each other out, causing Bloch-like transitions. If the terms differ significantly, each electron transition requires a relatively large amount of energy and the current is reduced. We find that imperfections result in increased high-harmonic gain. The spectral gain is mainly in high harmonic orders for low U and low orders for high U.
Shell-model study of58Ni using quantum computing algorithm
Authors: Bhoy Bharti , Stevenson Paul 
Published: June 2024

AbstractThis study presents a simulated quantum computing approach for the investigation into the shell-model energy levels of58Ni through the application of the variational quantum eigensolver (VQE) method in combination with a problem-specific ansatz. The primary objective is to achieve a fully accurate low-lying energy spectrum of58Ni. The chosen isotope,58Ni is particularly interesting in nuclear physics through its role in astrophysical reactions while also being a simple but non-trivial nucleus for shell-model study, it being two particles outside a closed shell. Our ansatz, along with the VQE method are shown to be able to reproduce exact energy values for the ground state and first and second excited states. We compare a classical shell model code, the values obtained by diagonalization of the Hamiltonian after qubit mapping, and a noiseless simulated ansatz+VQE simulation. The exact agreement between classical and qubit-mapped diagonalization shows the correctness of our method, and the high accuracy of the simulation means that the ansatz is suitable to allow a full reconstruction of the full nuclear wave function.
Time crystal embodies chimeralike state in periodically driven quantum spin system
Authors: Rahaman Mahbub , Sakurai Akitada , Roy Analabha 
Published: June 2024

Abstract
Chimera states are a captivating occurrence in which a system composed of multiple interconnected elements exhibits a distinctive combination of synchronized and desynchronized behavior. The emergence of these states can be attributed to the complex interdependence between quantum entanglement and the delicate balance of interactions among system constituents. The emergence of discrete-time crystal (DTC) in typical many-body periodically driven systems occurs when there is a breaking of time translation symmetry. Coexisting coupled DTC and a ferromagnetic dynamically many-body localized (DMBL) phase at distinct regions have been investigated under the controlled spin rotational error of a disorder-free spin-1/2 chain for different types of spin-spin interactions. We contribute a novel approach for the emergence of the DTC-DMBL-chimeralike state, which is robust against external static fields in a periodically driven quantum many-body system.
Research on the spatio-temporal evolution and impact of China’s industrial green development from the perspective of digital economy--based on analysis of 279 cities in China
Authors: Zhou Mengxing , Zhang Jinghua , Huang Ling , Lu Qiuping , Yuan Huimei , Bao Lingxin 
Published: June 2024

Abstract
Empowering industrial green development with the digital economy represents a crucial approach to advancing the green transformation of China’s economy and achieving high-quality economic development. Based on panel data from 279 cities in China from 2011 to 2021, this article uses the spatial econometrics model and threshold effect model to explore the spatial effect and nonlinearity of digital economy (DE) on industrial green development (IGD). The results show that, both DE and IGD exhibit fluctuating upward trends in China. There exists stronger spatial linkage effect in the eastern coastal areas, but this effect is weaker in the central and western regions. Furthermore, DE has significantly promoted IGD, and the conclusion remains robust after a series of endogeneity and robustness tests. Additionally, the promotion of the DE for IGD is characterized by regional spillovers and non-linear dynamics. The research results can serve as a theoretical support and decision-making basis for China to enhance industrial green development, promote the construction of an ecological civilization, and implement sustainable development strategies.
Efficient degradation of methyl red dye from the aqueous solution by individual bacterial and their consortium in a sugarcane bagasse waste-based media
Authors: Patel Bhakti , Desai Reema , Yadav Virendra Kumar , Choudhary Nisha , Ansari Mohammad Javed , Alharbi Sulaiman Ali , Patel Rajat , Thakkar Avani , Patel Ashish 
Published: June 2024

Abstract
Dye is one of the major pollutions around the whole world which have adverse effects on the environment and human beings. There is a requirement for an efficient, reliable, sustainable, and eco-friendly approach to the removal of dyes. In the present research, three individual bacterial strains Enterobacter aerogenes (MBX6), Klebsiella pneumoniae (MBC34), and Micrococcus luteus (MBC23) and their consortium was used to remove Methyl Red (MR) dye. The dye removal was observed at different initial concentrations of dye, nutrient media, additives in the nutrient media and sugarcane bagasse extract as a bacterial growth medium. The outcomes of the study showed that the bacterial consortium exhibits better removal efficiencies (63.6%) than individual bacterial strains and the dye removal percentage (75.19%) enhanced with increasing concentration of sucrose (3%) which was used as media additive. The addition of the sugar in nutrient medium resulted in more effective dye removal. The maximum removal of MR dye (98.6%) was achieved when the consortium was grown in a media containing pure sugarcane bagasse extract. The use of sugarcane bagasse extract (agricultural waste product) as a novel growth medium for the cultivation of bacteria possessing dye removal capabilities can offer a sustainable and cost-effective solution for industrial wastewater treatment.
Integrating multimodal Raman and photoluminescence microscopy with enhanced insights through multivariate analysis
Authors: Di Benedetto Alessia , Pozzi Paolo , Valentini Gianluca , Comelli Daniela 
Published: June 2024

Abstract
This paper introduces a novel multimodal optical microscope, integrating Raman and laser-induced photoluminescence (PL) spectroscopy for the analysis of micro-samples relevant in Heritage Science. Micro-samples extracted from artworks, such as paintings, exhibit intricate material compositions characterized by high complexity and spatial heterogeneity, featuring multiple layers of paint that may be also affected by degradation phenomena. Employing a multimodal strategy becomes imperative for a comprehensive understanding of their material composition and condition. The effectiveness of the proposed setup derives from synergistically harnessing the distinct strengths of Raman and laser-induced PL spectroscopy. The capacity to identify various chemical species through the latter technique is enhanced by using multiple excitation wavelengths and two distinct excitation fluence regimes. The combination of the two complementary techniques allows the setup to effectively achieve comprehensive chemical mapping of sample through a raster scanning approach. To attain a competitive overall measurement time, we employ a short integration time for each measurement point. We further propose an analysis protocol rooted in a multivariate approach. Specifically, we employ non-negative matrix factorization as the spectral decomposition method. This enables the identification of spectral endmembers, effectively correlated with specific chemical compounds present in samples. To demonstrate its efficacy in Heritage Science, we present examples involving pigment powder dispersions and stratigraphic micro-samples from paintings. Through these examples, we show how the multimodal approach reinforces material identification and, more importantly, facilitates the extraction of complementary information. This is pivotal as the two optical techniques exhibit sensitivity to different materials. Looking ahead, our method holds potential applications in diverse research fields, including material science and biology.
Remote plasma enhanced cyclic etching of a cyclosiloxane polymer thin film
Authors: Wang Xianglin , Luo Xinyu , Du Weiwei , Shen Yuanhao , Huang Xiaocheng , Yang Zheng , Zhao Junjie 
Published: June 2024

Abstract
The continuous evolution of chip manufacturing demands the development of materials with ultra-low dielectric constants. With advantageous dielectric and mechanical properties, initiated chemical vapor deposited (iCVD) poly(1,3,5-trimethyl-1,3,5-trivinyl cyclotrisiloxane) (pV3D3) emerges as a promising candidate. However, previous works have not explored etching for this cyclosiloxane polymer thin film, which is indispensable for potential applications to the back-end-of-line fabrication. Here, we developed an etching process utilizing O2/Ar remote plasma for cyclic removal of iCVD pV3D3 thin film at sub-nanometer scale. We employed in-situ quartz crystal microbalance to investigate the process parameters including the plasma power, plasma duration and O2 flow rate. X-ray photoelectron spectroscopy and cross-sectional microscopy reveal the formation of an oxidized skin layer during the etching process. This skin layer further substantiates an etching mechanism driven by surface oxidation and sputtering. Additionally, this oxidized skin layer leads to improved elastic modulus and hardness and acts as a barrier layer for protecting the bottom cyclosiloxane polymer from further oxidation.