bluuebunny/crossref_metadata_2025_split huggingface dataset:
Flow dynamics and theoretical modeling of monolayer ionic solutions confined within Ångstrom-scale channels
Authors: Wang Qiyuan , Zhou Runfeng , Sun Chengzhen 
Published: December 2024

Comprehending the flow dynamics of ionic solutions within nanoconfined spaces is imperative for diverse applications encompassing desalination, nanofiltration, energy storage, and electrochemical devices. When the confinement space is further reduced to 1 nm (Ångstrom scale), monolayer ionic solutions will emerge. In this regime, ions not only have the ability to influence water properties such as viscosity but also primarily modify the interactions and corresponding slip length (or friction coefficient) between the solution and wall. Notably, ion effects on water flow dynamics at Ångstrom scale exhibit unique characteristics compared to those at nanoscale and macroscale levels. In this study, we investigate the pressure-driven transport of monolayer ionic solution confined within two-dimensional graphene channels and explore the influences of ionic type, concentration, and valency on the flow rate of water via molecular dynamic simulations. Our findings reveal that divalent ions (e.g., Mg2+ and Ca2+) considerably reduce water flow rates due to enhanced viscosity and fluid–solid interface interaction compared to monovalent ions (e.g., Na+ and K+). Subsequently, we develop a theoretical model based on the Hagen–Poiseuille (HP) equation that incorporates modifications for ion-specific viscosity and slip length at the Ångstrom-scale level. By incorporating self-calculated values for water viscosity and friction coefficient/slip length at the graphene–water interface into our modified HP equation, water flow rate is basically predicted while emphasizing the critical role of ion–water interactions in Ångstrom-scale fluid transport.
Stability for a multi-frequency inverse random source problem
Authors: Wang Tianjiao , Xu Xiang , Zhao Yue 
Published: December 2024

Abstract
We present increasing stability estimates for the inverse random source problem of the Helmholtz equation in two and three dimensions by multi-frequency near-field data. The random source is assumed to be a microlocally isotropic generalized Gaussian random function such that its covariance is a classical pseudodifferential operator. We consider the use of either expectation of the correlation data or the data obtained from a single realization of the random source. For the direct problem, by exploring the regularity of the Green function, we demonstrate that the direct problem admits a unique bounded solution with an explicit integral representation. For the inverse problem, the analysis employs microlocal analysis to derive an estimate for the Fourier transform of the micro-correlation strength by the near-field correlation data and a high-frequency tail. The stability is achieved by showing the analyticity of the data and applying a novel analytic continuation principle. Furthermore, with the help of ergodicity, the stability estimate can be extended to the case of using only a single realization of the data. The stability estimates have a unified form which consists of the Lipschitz type data discrepancy and the logarithmic stability. The latter decreases as the upper bound of the frequency increases, which exhibits the phenomenon of increasing stability.
Gas-compensated thermal flow sensor using an integrated velocity-independent gas properties meter
Authors: Azadi Kenari S , Wiegerink R J , Sanders R G P , Lötters J C 
Published: December 2024

Abstract
A gas-compensated thermal flow sensor is presented that measures the flow rate in real-time, independent of the type of gas, by simultaneously measuring and compensating for the thermal conductivity and volumetric heat capacity of the gas. The thermal flow sensor consists of two free-hanging, heated wires, forming a calorimetric flow meter. The temperature difference between the two wires is a function of the flow rate and the fluid thermal properties. An additional heated wire is integrated on the same chip and used to measure the gas properties. This wire is suspended over a shallow V-groove cavity, and oriented perpendicular to the flow direction, so that it is only affected by the gas properties and not by the flow. DC excitation is used to measure the thermal conductivity, and AC excitation with the 3ω method is used to determine the volumetric heat capacity. The output of the thermal flow sensor is automatically corrected for the medium using these measured parameters. Measurements were performed with 11 different gases and gas mixtures, and in all cases the deviation between the applied flow rate and measured flow rate is less than 10%.
A multimass velocity-map and covariance-map imaging study of the dissociative electron ionisation dynamics of carbonyl sulphide (OCS)
Authors: Lomas James , Heathcote David , De Matos Loja Alexandre , Milešević Dennis , Robertson Patrick , Paterson Martin J , Vallance Claire 
Published: December 2024

Abstract
We present the results of a velocity-map imaging study into the dissociative electron ionisation dynamics of OCS at electron energies of 50, 75, and 100 eV, supported by new equation-of-motion coupled cluster and complete active space self consistent field (CASSCF) potential energy surface (PES) calculations for the OCS+ cation and OCS2+ dication. We report partial ionisation cross-sections and scattering distributions for the observed ionic fragments, and interpret these in terms of the dissociation dynamics of the singly and doubly charged OCS parent ions formed in the electron–molecule collisions. For many of the dissociation channels, consideration of the calculated PESs supplemented by comparison with data from photoionisation studies provides insight into the electronic PESs involved. For fragmentation products arising from dissociation of the dication, time-of-flight and recoil-frame covariance maps provide mechanistic insight into the stepwise dissociation mechanisms leading to these products and support previous conclusions by other authors.
Electron-impact ionization of Si IV–VIII in hot plasmas
Authors: Pain Jean-Christophe , Benredjem Djamel 
Published: December 2024

Abstract
In this work, we investigate the ionization of silicon by electron impacts in hot plasmas. Our calculations of the cross sections and rates rely on the Coulomb-Born-exchange, binary-encounter-dipole and distorted-wave methods implemented in the Flexible Atomic Code, and are compared with measurements and other theoretical values. We use a semi-empirical formula for the cross section, which involves a small set of adjustable parameters. Configuration interaction is taken into account and is shown to affect the cross section at low energy, in particular for Si3+. The rate coefficient is then expressed in terms of these parameters and is represented in a large temperature interval, up to 108 K. As expected, the agreement with measurements improves for increasing ion charges, confirming the applicability of our approach to hot plasma studies such as inertial-confinement fusion, and its reliability.
Cr3+ doped ZnGa2O4 micro-flowers as stable saturable absorber media
Authors: Choudhury Shouvik , Sirohi Sugandh , Narayanan Shruti , Bisht Prem B 
Published: December 2024

Abstract
Micro-flowers of Cr3+ doped ZnGa2O4, a spinel compound with high chemical and thermal stability is synthesized by hydrothermal method. Flower-like structures in the micrometer range made up of secondary nanoflakes are evident from the field emission scanning electron microscope images. X-ray photoelectron spectroscopy studies confirm the presence of Cr3+ dopants. The steady-state optical characterizations show higher absorbance of the samples in the ultraviolet (UV) region. Due to introduction of the d–d electron transition states of Cr3+ ions, ZnGa2O4:Cr3+ exhibits a prominent red near infrared (NIR) luminescence. Optical nonlinearity studies show that Cr3+ doping changes the nonlinear absorption from reverse saturable absorption to saturable absorption. This is due to the introduction of an excitation band owing to 4T1-4A2 transition of Cr3+ ion.
A generalized zero-shot semantic learning model for batch process fault diagnosis
Authors: Liu Kai , Zhao Xiaoqiang , Mou Miao , Hui Yongyong 
Published: December 2024

Abstract
In industrial monitoring, although zero-shot learning successfully solves the problem of diagnosing unseen faults, it is difficult to diagnose both unseen and seen faults. Motivated by this, we propose a generalized zero-shot semantic learning fault diagnosis model for batch processes called joint low-rank manifold distributional semantic embedding and multimodal variational autoencoder (mVAE). Firstly, joint low-rank representation and manifold learning makes the training samples map to the low-rank space, which obtains the global–local features of the samples while reducing the redundancy in the inputs for the training model; secondly, the bias of human-defined semantic attributes is corrected by predicting the attribute error rate; then, fault samples and corrected semantic vectors are embedded into the consistency space, in which the samples are reconstructed using the mVAE to fully integrate the cross-modal information, meanwhile, Barlow matrix is designed to measure the consistency between the fault samples and the attribute vectors, the higher the consistency, the higher the learning efficiency of attribute classifiers; finally, the generalized zero-shot fault diagnosis experiments are designed and conducted on the penicillin fermentation process and the semiconductor etching process to validate the effectiveness, the results show that the proposed model is indeed possible to diagnose target faults without their samples.
A systematic review on interpretability research of intelligent fault diagnosis models
Authors: Peng Ying , Shao Haidong , Xiao Yiming , Yan Shen , Wang Jie , Liu Bin 
Published: December 2024

Abstract
Recent years have witnessed a surge in the development of intelligent fault diagnosis (IFD) mostly based on deep learning methods, offering increasingly accurate and autonomous solutions. However, they overlook the interpretability of models, and most models are black-box models with unclear internal mechanisms, thereby reducing users’ confidence in the decision-making process. This is particularly problematic for critical decisions, as a lack of clarity regarding the diagnostic rationale poses substantial risks. To address these challenges, a more reliable, transparent, and interpretable system is urgently demanded. Research on the interpretability of IFD has gained momentum and stands today as a vibrant area of study. To promote in-depth research and advance the development of this field, a thorough examination of existing journal articles on interpretable fault diagnosis models is essential. Such a review will demystify current technologies for readers and provide a foundation for future investigation. This article aims to give a systematic review of the state-of-the-art interpretability research in the field of IFD. We present a systematic review of recent scholarly work on interpretable models in this domain, categorizing them according to their methodologies and structural attributes. In addition, we discuss the challenges and future research directions for the interpretability of IFD.
Impact of nuclear fragmentation on the stopping power ratio of 12C ion beams
Authors: Saße Pascal , Stolzenberg Jessica , Baumann Kilian , Poppe Björn , Looe Hui Khee 
Published: December 2024

Abstract

Objective: Nuclear fragmentation generates a diverse dosimetric environment in the path of 12C ion beams. Concise parametrization of the beam’s composition is paramount for determining key correction factors in clinical dosimetry. This study sets out to provide such a parametrization based on detailed Monte Carlo simulations of clinically relevant 12C beams. Special attention was paid to the products of nuclear fragmentations and their importance in determining the stopping power ratios. Approach: Using the Monte Carlo simulation package GATE, the spectral fluence of all primary and secondary particles in water were computed at different depths for selected clinically relevant incident energies. Collision-stopping power data was taken from the ICRU90, SRIM and MSTAR database, as well as from previous publications. Main results: The choice of stopping power data was shown to have a bigger impact on the resulting stopping power ratio than the choice of physics lists for the simulations. Significance: A comprehensive analysis of the relationship between fragmentation and dosimetric data has been provided. This study compared different methods for determining spectral fluence-based stopping power ratios, which is essential for accurate ion beam dosimetry.
Simulating atherosclerotic plaque mechanics using polyvinyl alcohol (PVA) cryogel artery phantoms, ultrasound imaging and inverse finite element analysis
Authors: Guendouz Yasmine , Razif Noor Adeebah Mohamed , Bernasconi Floriane , Brien Gordon O’ , Johnston Robert D , Lally Caitríona 
Published: December 2024

Abstract
The clinical decision to establish if a patient with carotid disease should undergo surgical intervention is primarily based on the percent stenosis. Whilst this applies for high-grade stenosed vessels (>70%), it falls short for other cases. Due to the heterogeneity of plaque tissue, probing the mechanics of the tissue would likely provide further insights into why some plaques are more prone to rupture. Mechanical characterization of such tissue is nontrivial, however, due to the difficulties in collecting fresh, intact plaque tissue and using physiologically relevant mechanical testing of such material. The use of polyvinyl alcohol (PVA) cryogel is thus highly convenient because of its acoustic properties and tunable mechanical properties. Methods. The aim of this study is to demonstrate the potential of PVA phantoms to simulate atherosclerotic features. In addition, a testing and simulation framework is developed for full PVA vessel material characterization using ring tensile testing and inflation testing combined with non-invasive ultrasound imaging and computational modeling. Results. Strain stiffening behavior was observed in PVA through ring tensile tests, particularly at high (n = 6) freeze–thaw cycles (FTCs). Inflation testing of bi-layered phantoms featuring lipid pool inclusions demonstrated high strains at shoulder regions. The application of an inverse finite element framework successfully recovered boundaries and determined the shear moduli for the PVA wall to lie within the range 27–53 kPa. Conclusion. The imaging-modeling framework presented facilitates the use and characterization of arterial mimicking phantoms to further explore plaque rupture. It also shows translational potential for non-invasive mechanical characterization of atherosclerotic plaques to improve the identification of clinically relevant metrics of plaque vulnerability.
The role of local active stiffness on the natural frequency of a flexible propulsor
Authors: Rodriguez Miguel Perilla , Musgrave Patrick F 
Published: December 2024

Abstract
This study identifies how local changes in active stiffness affect the natural frequency of a bio-inspired flexible propulsor. Biological swimmers actively change their body stiffness and natural frequency to maintain high swimming performance during steady swimming, acceleration, and maneuvering. However, it is not well understood how local active stiffness along the body affects the propulsor’s global stiffness and natural frequency. This study identifies the relationship between the propulsor’s natural frequency and the magnitude, spatial location, and application length of the active stiffness. We use a numerical kinematic model of a flexible bio-inspired propulsor with Euler–Bernoulli beam theory, inertial fluid-structure interactions, and active stiffness via co-contraction of piezoelectric artificial muscles to generate local in-plane forces. Using this numerical model, we uncover the fundamental mechanism by which the in-plane forces change the natural frequency. Local in-plane compressive forces increase the natural frequency, and there is a critical compressive force at which the propulsor’s first and second natural frequencies converge to yield a dynamic instability. We establish that the change in natural frequency is governed by the interplay between the spatial location and application length of the active stiffness. The propulsor is most sensitive to changes in natural frequency when the active stiffness is applied at the propulsor’s peduncle, but the largest changes in natural frequency occur when the active stiffness is applied with a long muscle centered along the anterior–posterior axis. We show that artificial muscles can change the natural frequency via local in-plane forcing, but practical implementation will require artificial muscles with high ratios of blocking force to passive muscle stiffness. These results serve as a framework for future studies that will identify the relationship between swimming performance (thrust and efficiency) and locally applied active stiffness.
Influence of Fe2O3 and La2O3 nanoparticles on the performance of domestic refrigerator functioning with R134a refrigerant
Authors: Prabu R , Velmurugan D , Vijayakumar S R , Maniyarasan M 
Published: December 2024

Abstract
Domestic refrigerator is working on the principle of Vapour Compression Refrigeration (VCR) system. VCR system uses compressor as one the functional member which consumes electrical energy. Due to the civilization, the usages of VCR system based equipments are increasing. Therefore, the need for electrical energy is on the rise. Therefore, the limited usage of electrical energy is desirable. Consequently, this study aimed to reduce electrical energy consumption and enhance the performance of the VCR system by using nano-refrigerants as the working medium. This research utilized two types of nano-refrigerants: R134a/Fe2O3 and R134a/La2O3.The nanoparticles concentration was varied from 0.1 g l−1 to 0.5 g l−1 and the best refrigerant was identified by comparing the performance of VCR operated with aforementioned nano-refrigerants. The properties like thermal conductivity and viscosity of nano-refrigerants were determined and compared with R134a refrigerant. Further, the power consumption, pull down time and COP of VCR system was investigated. Results revealed that the R134a/Fe2O3 and R134a/La2O3 nano-refrigerant displayed superior characteristics and showed greater performance. The R134a/Fe2O3 demonstrated a peak thermal conductivity (0.022 W mK−1) when 0.5 g l−1 of nanoparticles were added. Further, the same refrigerant showed 27.4% decrease in electrical energy consumption compared to R134a refrigerant and showed a maximum COP of 3.5. Therefore, this study suggests that the R134a/0.5 g l−1 Fe2O3 could be an effective choice to lower the power consumption of the VCR system.
Performance analysis based on biomolecule position and pH-sensing mechanism for vertical TFET
Authors: Wadhwa Girish , Thakur Anchal , Taibi Angelo , Proto Antonino 
Published: December 2024

Abstract
In this study, the impact of the diffusion mechanism of a biomolecule in the nanocavity (

T

b
i
o

) region on the electrical characteristics of a split-gate, step-channel electrolyte-insulated semiconductor vertical TFET (SGSC-EIS-VTFET) pH biosensor was investigated. The impact of the transport sensing mechanism, that is, diffusion-limited process and rapid mixing process of biomolecules in the nanocavity sensing area, on the pH of the analyte was also examined. Physics-based modelling was used to determine the interface charge density at the oxide-silicon interface of the proposed vertical TFET pH biosensor. We also considered the effect of pH values on the proposed device performance, like drain current (I
ds), transconductance (gm), current sensitivity (SID), and voltage sensitivity (SV) after the inclusion of electrolyte medium. Here, the maximum SV ∼ 145 mH pH−1 for

T

b
i
o

= 6 nm, which is higher than the Nernstian limit (59.2 mV pH−1), and SID has been enhanced by 10 times per pH variation. This study indicated that the diffusion of biomolecules significantly impacts the performance parameters of the proposed structure because of the realistic dominance of the sensing mechanism and the conjugation of analyte on the sensing area.
Oxidation temperature influence on the properties of oxide layers thermally grown on 4H-SiC by wet oxidation
Authors: Dartora G H S , Radtke C , Stedile F C 
Published: December 2024

Abstract
The compositional characteristics of oxide layers thermally grown on 4H-SiC were investigated as a function of oxidation temperature. We tracked the evolution of the oxide properties over different oxidation times. Two distinct oxidation regimes were identified: an initial phase where a substoichiometric oxide forms, followed by its conversion into SiO2. Oxidation temperature proved to be a key parameter in achieving stoichiometric SiO2. At the lowest temperature used in this study (900 °C), only substoichiometric layers were produced. Additionally, our results indicate a similar behavior for both wet and dry SiC oxidation processes, suggesting that both involve a multi-step mechanism.
A local infall from a cosmographic analysis of Pantheon+
Authors: Sorrenti Francesco , Durrer Ruth , Kunz Martin 
Published: December 2024

Abstract
We present a model independent analysis of the Pantheon+ supernova sample and study the dependence of the recovered values of H
0, q
0 and j
0 on the redshift cut and on the modeling of peculiar velocities. In addition to the bulk velocity discussed previously, we also find a significant infall that we attribute to the presence of an overdensity out to a radius of R ≃ 120h
-1Mpc.
Structure formation with primordial black holes: collisional dynamics, binaries, and gravitational waves
Authors: Delos M. Sten , Rantala Antti , Young Sam , Schmidt Fabian 
Published: December 2024

Abstract
Primordial black holes (PBHs) could compose the dark matter content of the Universe. We
present the first simulations of cosmological structure formation with PBH dark matter that
consistently include collisional few-body effects, post-Newtonian orbit corrections, orbital decay
due to gravitational wave emission, and black-hole mergers. We carefully construct initial
conditions by considering the evolution during radiation domination as well as early-forming
binary systems. We identify numerous dynamical effects due to the collisional nature of PBH dark
matter, including evolution of the internal structures of PBH halos and the formation of a hot
component of PBHs. We also study the properties of the emergent population of PBH binary systems,
distinguishing those that form at primordial times from those that form during the nonlinear
structure formation process. These results will be crucial to sharpen constraints on the PBH
scenario derived from observational constraints on the gravitational wave background. Even under
conservative assumptions, the gravitational radiation emitted over the course of the simulation
appears to exceed current limits from ground-based experiments, but this depends on the evolution
of the gravitational wave spectrum and PBH merger rate toward lower redshifts.
Low temporal radiation coherence of noise-like pulses
Authors: Kobtsev S , Serebrennikov K 
Published: December 2024

Abstract
It is quite well-known that coherence is an intrinsic property of laser radiation. However, after the advent of noise-like pulses, it turns out that the temporal coherence of their radiation is low and the electromagnetic field oscillations in adjacent noise-like pulses are not correlated. This work experimentally studies for the first time the degree of coherence of electromagnetic field oscillations inside a noise-like pulse. We measure the visibility of interference fringes at the exit from a Michelson interferometer when its optical path difference is scanned around zero up to and exceeding the length of the noise-like pulse. The experimental data indicate close to zero temporal coherence of radiation within noise-like pulses.