bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ab Initio Calculation of Fluid Properties for Precision Metrology
Authors: Garberoglio Giovanni , Gaiser Christof , Gavioso Roberto M. , Harvey Allan H. , Hellmann Robert , Jeziorski Bogumił , Meier Karsten , Moldover Michael R. , Pitre Laurent , Szalewicz Krzysztof , Underwood Robin 
Published: September 2023

Recent advances regarding the interplay between ab initio calculations and metrology are reviewed, with particular emphasis on gas-based techniques used for temperature and pressure measurements. Since roughly 2010, several thermophysical quantities – in particular, virial and transport coefficients – can be computed from first principles without uncontrolled approximations and with rigorously propagated uncertainties. In the case of helium, computational results have accuracies that exceed the best experimental data by at least one order of magnitude and are suitable to be used in primary metrology. The availability of ab initio virial and transport coefficients contributed to the recent SI definition of temperature by facilitating measurements of the Boltzmann constant with unprecedented accuracy. Presently, they enable the development of primary standards of thermodynamic temperature in the range 2.5–552 K and pressure up to 7 MPa using acoustic gas thermometry, dielectric constant gas thermometry, and refractive index gas thermometry. These approaches will be reviewed, highlighting the effect of first-principles data on their accuracy. The recent advances in electronic structure calculations that enabled highly accurate solutions for the many-body interaction potentials and polarizabilities of atoms – particularly helium – will be described, together with the subsequent computational methods, most often based on quantum statistical mechanics and its path-integral formulation, that provide thermophysical properties and their uncertainties. Similar approaches for molecular systems, and their applications, are briefly discussed. Current limitations and expected future lines of research are assessed.
Nanorod length-dependent photodriven H2 production in 1D CdS–Pt heterostructures
Authors: Liu Yawei , Yang Wenxing , Chen Qiaoli , Xie Zhaoxiong , Lian Tianquan 
Published: September 2023

Colloidal quantum confined semiconductor-metal heterostructures are promising candidates for solar energy conversion because their light absorbing semiconductor and catalytic components can be independently tuned and optimized. Although the light-to-hydrogen efficiencies of such systems have shown interesting dependences on the morphologies of the semiconductor and metal domains, the mechanisms of such dependences are poorly understood. Here, we use Pt tipped 0D CdS quantum dots (with ∼4.6 nm diameter) and 1D CdS nanorods (of ∼13.8, 27.8, 66.6, and 88.9 nm average rod lengths) as a model system to study the distance-dependence of charge separation and charge recombination times and their impacts on photo-driven H2 production. The H2 generation quantum efficiency increases from 0.2% ± 0.0% in quantum dots to 28.9% ± 0.4% at a rod length of 28 nm and shows negligible changes at longer rod lengths. The half-life time of electron transfer from CdS to Pt increases monotonically with rod length, from 0.7 ± 0.1 in quantum dots to 170.2 ± 29.5 ps in the longest rods, corresponding to a slight decrease in electron transfer quantum efficiency from 92% to 81%. The amplitude-weighted average lifetime of charge recombination of the electron in Pt with the hole in CdS increases from 4.7 ± 0.4 µs in quantum dots to 149 ± 34 µs in 28 nm nanorods, and the lifetime does not increase further in longer rods, resembling the trend in the observed H2 generation quantum efficiency. Our result suggests that the competition of the charge recombination process with the hole removal by the sacrificial electron donor plays a dominant role in the observed nanorod length dependent overall light driven H2 generation quantum efficiency.
Structural design and experimental evaluation of a coarse–fine parallel dual-actuation XY flexure micropositioner with low interference behavior
Authors: Chen Yunzhuang , Lai Leijie , Zhu Limin 
Published: September 2023

This paper proposes a novel two degree of freedom large range coarse–fine parallel dual-actuation flexure micropositioner (CFPDFM) with low interference behavior. First, the structure and working principle of the CFPDFM are introduced. Then, based on the stiffness matrix method, the analytical models of the motion range, input stiffness, and amplification ratio of the mechanism are established. Subsequently, the accuracy of the analytical model is verified by finite element analysis and experiments. Moreover, the dual-servo cooperative drive control strategy is designed to improve the closed-loop positioning ability of the CFPDFM. Finally, the CFPDFM experimental system is built to verify the plane trajectory tracking performance. The results reveal that the micropositioner can achieve a total range of 3.02 × 3.11 mm2, a resolution of ≤40 nm, low interference performance of coarse and fine actuators, good cross-axis decoupling, and planar complex trajectory tracking performance, while possessing a compact structure. It can be used in many plane positioning situations requiring large range and high precision.
Shear viscosity of OPC and OPC3 water models
Authors: Ando Tadashi 
Published: September 2023

Water is a unique and abundant substance in biological and chemical systems. Considering its importance and ubiquity, numerous water models have been developed to reproduce various properties of bulk water in molecular simulations. Therefore, selecting an appropriate water model suitable for the properties of interest is crucial for computational studies of water systems. The four-point Optimal Point Charge (OPC) and three-point OPC (OPC3) water models were developed in 2014 and 2016, respectively. These models reproduce numerous properties of bulk water with high accuracy, such as density, dielectric constant, heat of vaporization, self-diffusion coefficient, and surface tension. In this study, we evaluated the shear viscosities of the OPC and OPC3 water models at various temperatures ranging from 273 to 373 K using the Green–Kubo formalism to assess their performance. The evaluated viscosities of both models were very close to each other at all the examined temperatures. At temperatures above 310 K, the calculated shear viscosities were in excellent agreement with the experimental results. However, at lower temperatures, the water models systematically underestimated the shear viscosity, with the calculated values at 273 and 298 K being 20% and 10% lower than the experimental values, respectively. Despite this limitation, the OPC and OPC3 water models outperformed other widely used water models.
The 103Rh NMR spectroscopy and relaxometry of the rhodium formate paddlewheel complex
Authors: Harbor-Collins Harry , Sabba Mohamed , Moustafa Gamal , Legrady Bonifac , Soundararajan Murari , Leutzsch Markus , Levitt Malcolm H. 
Published: September 2023

The nuclear magnetic resonance (NMR) spectroscopy of spin-1/2 nuclei with low gyromagnetic ratio is challenging due to the low NMR signal strength. Methodology for the rapid acquisition of 103Rh NMR parameters is demonstrated for the case of the rhodium formate “paddlewheel” complex Rh2(HCO2)4. A scheme is described for enhancing the 103Rh signal strength by polarization transfer from 1H nuclei, which also greatly reduces the interference from ringing artifacts, a common hurdle for the direct observation of low-γ nuclei. The 103Rh relaxation time constants T1 and T2 are measured within 20 min by using 1H-detected experiments. The field dependence of the 103Rh T1 is measured. The high-field relaxation is dominated by the chemical shift anisotropy mechanism. The 103Rh shielding anisotropy is found to be very large: |Δσ| = 9900 ± 540 ppm. This estimate is compared with density functional theory calculations.
Investigation of electric transport in mixed conducting Na2O modified zinc borate glasses for electrode material using broadband dielectric spectroscopy
Authors: Ahlawat Jyoti , Pawaria Suman , Redhu Preeti , Dahiya Sajjan , Ohlan Anil , Punia Rajesh , Maan A. S. 
Published: September 2023

The electrical conductivity of Na2O substituted zinc borate glasses has been studied in the frequency range of 10 mHz to 1 MHz and in the temperature range from 313 to 573 K. The conduction mechanism has been ascertained using the values of the frequency exponent (s) extracted from the fitting of experimental data of the real part of electric conductivity in light of the Almond–West equation. Depending on the glass composition, the ac conduction in the glasses happened via correlated barrier hopping and non-overlapping small polaron tunneling conduction models. The electric modulus studies support the assertion of composition dependent conduction mechanisms. Furthermore, electronic conduction and ionic conduction have been studied from impedance investigations. Equivalent circuit models were used to fit the Nyquist and Bode plots of each sample at the temperatures under consideration. It has been found that the activation energy values calculated from conductivity, electric modulus, and impedance measurements are more or less the same.
Machine learning molecular dynamics simulation of CO-driven formation of Cu clusters on the Cu(111) surface
Authors: Halim Harry H , Ueda Ryo , Morikawa Yoshitada 
Published: September 2023

Abstract
The behavior of adsorbate-induced surface transformation can be clearly understood given the mechanical aspects of such phenomenon are well described at the atomic level. In this study, we provide the atomic-level description on the formation of Cu clusters on the Cu(111) surface by performing set of molecular dynamics simulations driven by machine-learning force-field. The simulations at 450 K–550 K show clusters are formed within a hundred of ns when the Cu surface is exposed with CO. On the other hand, no cluster is formed within the same time interval on the clean Cu surface even at 550 K, which signifies the importance of CO exposure to the surface transformation. The effect of temperature to the formation of clusters is also investigated. The CO-decorated Cu clusters ranging from dimer to hexamer are detected within a hundred of ns at 450 K. Lowering the temperature to 350 K does not result in the formation of clusters within a hundred ns due to the scarce detachments of adatom, while raising the temperature to 550 K results in the formation of more clusters, ranging from dimer to heptamer, but with shorter lifetimes. The clusters can be formed directly through instantaneous detachment of a group of step-atoms, or indirectly by aggregation of wandering Cu monomers and smaller clusters on the surface terrace. The preference to the indirect mechanism is indicated by the higher frequency of its occurrence. Set of nudged elastic band calculations has been performed to confirm the promotion of CO adsorptions to the detachment of Cu step-atoms by lowering the detachment barrier.
A deep neural network with electronic nose for water stress prediction in Khasi Mandarin Orange plants
Authors: Sharma Chayanika , Barkataki Nairit , Sarma Utpal 
Published: September 2023

Abstract
Water stress is a significant environmental factor that hampers plant productivity and leads to various physiological and biological changes in plants. These include modifications in stomatal conductance and distribution, alteration of leaf water potential & turgor loss, altered chlorophyll content, and reduced cell expansion and growth. Additionally, water stress induces changes in the emission of volatile organic compounds across different parts of the plants. This study presents the development of an electronic nose (E-nose) system integrated with a deep neural network (DNN) to detect the presence and levels of water stress induced in Khasi Mandarin Orange plants. The proposed approach offers an alternative to conventional analytical methods that demand expensive and complex laboratory facilities. The investigation employs the leaf relative water content (RWC) estimation, a conventional technique, to evaluate water stress induction in the leaves of 20 plants collected over a span of 9 days after stopping irrigation. Supervised pattern recognition algorithms are trained using the results of RWC measurement, categorising leaves into non-stressed or one of four stress levels based on their water content. The dataset used for training and optimising the DNN model consists of 27 940 samples. The performance of the DNN model is compared to traditional machine learning methods, including linear and radial basis function support vector machines, k-nearest neighbours, decision tree, and random forest. From the results, it is seen that the optimised DNN model achieves the highest accuracy of 97.59% in comparison to other methods. Furthermore, the model is validated on an unseen dataset, exhibiting an accuracy of 97.32%. The proposed model holds the potential to enhance agricultural practices by enabling the detection and classification of water stress in crops, thereby aiding in water management improvements and increased productivity.
Generation of high-dimensional vibration signal and its application in fault diagnosis
Authors: Ren Zhijun , Gao Dawei , Zhu Yongsheng , Yan Ke , Hong Jun , Feng Ke 
Published: September 2023

Abstract
Imperfect data, such as data scarcity and imbalance, have a negative impact on intelligent fault diagnosis. Generative adversarial networks (GANs) have proven to be a potential method for augmenting data. However, the overall quality of data generated by GANs still requires improvement. In this study, a multiscale feature-fusion GAN was proposed for generating high-dimensional signals. A strategy that generates signals with dimensionality higher than the desired dimensionality was proposed. The generated signals were resampled to improve the phase diversity of the generated signals. To enhance the feature extraction capability of the GAN for high-dimensional signals, a multiscale feature extraction structure was designed. The integration of multiscale feature extraction and fusion was achieved without a significant increase in the computational burden. To enhance the amplitude diversity of the generated signals, a reconstruction network was designed that directly constrained the spatial distribution of the generated signals. Experimental results show that the model has advantages in terms of the similarity and diversity of the generated signals. The effectiveness of the model in fault diagnosis was verified using two motor datasets, where the fault diagnosis model using the sample set augmented by the proposed model obtained a 36.32% improvement in accuracy compared with using the original sample set. In addition, in comparison experiments, the model achieved a higher diagnostic accuracy improvement of 28.87% compared to four other published models.
Evaluation of polycaprolactone nanofibers’ spinnability using green solvent systems by solution blow spinning (SBS)
Authors: Teixeira Bruna N , Anaya-Mancipe Javier M , Thiré Rossana Mara S M 
Published: September 2023

Abstract
Solution blow spinning (SBS) is a promising alternative to produce fibrous matrices for a wide range of applications, such as packaging and biomedical devices. Polycaprolactone (PCL) is a biodegradable polyester commonly used for spinning. The usual choices for producing PCL solutions include chlorinated solvents (CS), such as chloroform. However, the high toxicity of CS makes it difficult for biological and green applications. This work evaluates the influence of two less toxic solvents, acetic acid (AA) and acetone (Acet), and their mixtures (AA/Acet) on the properties of PCL fibers produced by SBS. The results showed that Acet does not cause degradation of the PCL chains, in opposition to AA. Furthermore, adding acetone to the acetic acid tended to preserve the size of PCL chains. It was not possible to produce fibers using PCL in 100% acetone. However, the AA/Acet mixture allowed the efficient production of PCL fibers. The proportion of Acet and AA in the mixture modulated the fiber morphology and orientation, making it possible to use this green solvent system according to the desired application.
How to overcome the demagnetization of superconducting Halbach arrays?
Authors: Houbart M , Fagnard J-F , Dular J , Dennis A R , Namburi D K , Durrell J H , Geuzaine C , Vanderheyden B , Vanderbemden P 
Published: September 2023

Abstract
Assembling trapped-field superconducting magnets with mutually orthogonal magnetizations directions in a Halbach array configuration offers the prospect of generating both high fields and large field gradients. A major issue when assembling bulk superconductors in a Halbach array, however, consists in the alteration of the initial current density distribution during the assembly process. This reorganization of supercurrent loops limits the field generated by the system. We investigate two methods for reducing this demagnetization effect. The first method consists of using stacked tapes instead of bulk superconductors. For the second method, we propose a procedure leading to a re-magnetizing the superconductors of the array after the assembly. The procedure consists in putting two superconductors on top of one another, magnetizing them along the vertical direction, and then keeping the pair in place while two other superconductors, magnetized in an horizontal direction, are approached from left and right. The top central sample is then removed from the array, thereby providing the desired re-magnetization of the bottom one. The benefits of this procedure was investigated by finite element modelling and experiments carried out at 77 K both with bulk YBa2Cu3O

7
−
x

superconductors (

∼

14
×
14
×
14

mm3) and with stacks of second generation YBa2Cu3O

7
−
x

tapes from Superpower (

∼

12
×
12
×
12

mm3). The flux density measured above the array is compared to analytical results and finite element simulations. The results show that a re-magnetization of the central sample occurs, which allows the maximum field generated with Halbach arrays made of three bulk superconductors or three stacked tapes to be increased by 5% and 11% respectively. Numerical modelling shows that using a taller top sample with this method allows to recover almost the full potential of the array.
Stationary and moving bright solitons in Bose–Einstein condensates with spin–orbit coupling in a Zeeman field
Authors: He Juntao , Lin Ji 
Published: September 2023

Abstract
We explore the existence and stability domains of stationary and moving bright solitons in spin–orbit-coupled spin-1 Bose–Einstein condensates in an external Zeeman field. Two families of bell-shape bright solitons (plane-wave (PW) phases) and two families of stripe-shape bright solitons (standing-wave (SW) phases) are obtained. We find a relation between the existence of these bright solitons and the single-particle energy spectrum, as well as the requirements of their existence for atomic interactions. The stability of four families of bright solitons is systematically analyzed using the linear stability analysis method. For two families of PW bright solitons, they are unstable only when the strength of the Zeeman field is above a critical value. The critical value is affected by the spin–orbit coupling and hardly affected by atomic interactions. When the velocities of solitons are zero (nonzero), the critical values of these two families are equal (unequal). For two families of SW bright solitons, their stability domains are identical in the absence of the Zeeman field, and they are unstable when the ferromagnetic interaction is strong. In the presence of the Zeeman field, their stability domains are complementary and complex, and one family of SW bright solitons can exist stably in the area with stronger ferromagnetic interaction. Furthermore, we find the collisions of stable bright solitons with different velocities can generate intriguing dynamics.
Energy gains at daily periodic changes of the azimuths of PV modules in north-east Bulgaria
Authors: Penkova N Y , Krumov K S , Hristov P V 
Published: September 2023

Abstract
The higher efficiency of tracking photovoltaic systems is an indisputable fact and computational methods of the respective energy gains are well known. However the investments in the tracking systems are higher in comparison to the fixed ones due to the needs of additional equipment and automation systems. An options of periodical change of the azimuth of PV modules at single axis solar trackers and the correspondent incident solar energy are studied in this paper. An approach for numerical determination of the daily periods of cyclic rotations of the trackers and the subsequent electricity production is developed. It was applied to estimate the energy gains at such cyclic changes of a PV system in ceramic factory in Bulgaria.
Sustainable management and comprehensive administrative control of asphalt pavements case study, Perú
Authors: Almeida Mercedes Evangelina Lopez , Aparco Rosa Huaraca , Lipa Rocío Cahuana , Mamani Julio César Machaca , Villafuerte Mario Moises Cuaquera , Valenzuela Jubenal Mendoza , Ascue Esther Reyna Merino , Ccorisapra Yovana Flores , Ramos Martha Teresa Ecos , Otero Calixto Cañari , Chipana Salvador Quispe , Pacheco Niki Franklin Flores 
Published: September 2023

Abstract
The management of asphalt pavements is of great importance for the development of road, motorway and airport runway infrastructures. For the company to achieve its goals, the use of administrative control instruments or tools such as evaluations and follow-ups of employees. Such control begins with the design by the company of an organizational structure where activities are planned and their effectiveness with their subsequent evaluations. The study aimed to analyze the management of asphalt maintenance and its administration process in a pavement and construction company in the Lima region, Peru. The methodology used was the hypothetical deductivo. Thedesign was non-experimental and cross-sectional deliberating the variables in a single time of study in a descriptive way, the sample population was the administrative workers and workers to perform the research technique, the type of instrument used was the survey with anonymous questions and closed questions, or at least all those questions that best respond to the situation we want to know. An analysis of frequencies and weighting of percentages was made from which it obtained, the values that allowed us to know the problems of the company with respect to the variables under study such as administrative control and maintenance, the validity of the instrument had a degree of reliability of Cronbach’s alpha of 0.879 for the variable Administrative control and maintenance of 0.849. In the research regarding the dimensions of asphalt pavement have a relationship with the administrative management of the company, having a positive significance.