bluuebunny/crossref_metadata_2025 huggingface dataset:
Correction: A Δ-machine learning approach for force fields, illustrated by a CCSD(T) 4-body correction to the MB-pol water potential
Authors: Qu Chen , Yu Qi , Conte Riccardo , Houston Paul L. , Nandi Apurba , Bowman Joel M.
Published: October 2022

Correction for ‘A Δ-machine learning approach for force fields, illustrated by a CCSD(T) 4-body correction to the MB-pol water potential’ by Chen Qu et al., Digital Discovery, 2022, 1, 658–664, https://doi.org/10.1039/D2DD00057A.
Enhancing magnetic relaxation through subcomponent self-assembly from a Dy2to Dy4grid
Authors: Li Xiao-Lei , Ma Zhifang , Wu Jinjiang , Zhou Quan , Tang Jinkui
Published: October 2022

Linear Dy2and grid-like Dy4compounds were constructedviasubcomponents self-assembly where the structures and magnetic properties were modulatedviathe different coordinated anions provided by DyIIIsalts.
Synthesis and characterization of a novel stimuli-responsive zein nano delivery system for the controlled release of emamectin benzoate
Authors: Wang Anqi , Li Ningjun , Shen Yue , Sun Changjiao , Wang Chong , Zhao Xiang , Cui Bo , Wang Chunxin , Zhan Shenshan , Li Xingye , Cui Haixin , Wang Yan
Published: October 2022

A pH/enzyme dual-responsive zein-EMB-nanocapsule system was prepared via a phase-separation method, which could enhance the pesticide's adhesion, target wettability, stability, anti-photolysis, and stimuli-responsive controlled release properties.
Hepatopreventive properties of hydroxytyrosol and mannitol-rich extracts obtained from exhausted olive pomace using green extraction methods
Authors: Contreras María del Mar , Gómez-Cruz Irene , Feriani Anouar , Alwasel Saleh , Harrath Abdel Halim , Romero Inmaculada , Castro Eulogio , Tlili Nizar
Published: October 2022

Hydroxytyrosol and mannitol rich extracts from exhausted olive pomace were obtained by green extraction methodologies. Supplementation of these extracts alleviated CCl4-induced hepatic damage and protected DNA.
Anti-fatigue effects of enzyme-hydrolyzed okara in C2C12 myotubes and Sprague–Dawley rats
Authors: Chien Yu-Jou , Yen Gow-Chin , Huang Shih-Chien , Chen Shiuan-Chih , Hsu Chin-Lin
Published: October 2022

Okara protein hydrolysate (OPH) could exert anti-fatigue effects both in vivo and in vitro through an improvement in mitochondrial function.
A comprehensive review on lactoferrin: a natural multifunctional glycoprotein
Authors: Shini V. S. , Udayarajan Chinthu Tharayil , Nisha P.
Published: October 2022

Health benifts and appplication of lactoferrin.
Oxygen and sulfur dual vacancy engineering on a 3D Co3O4/Co3S4heterostructure to improve overall water splitting activity
Authors: Wang Qing , Xu Hui , Qian Xingyue , He Guangyu , Chen Haiqun
Published: October 2022

Oxygen, sulfur dual vacancy-rich Co3O4/Co3S4heterojunction nanoflowers were grown on nickel foam (DV-Co3O4/Co3S4@NF) using hydrothermal and reduction strategies and assembled as efficient bifunctional electrocatalysts for overall water splitting.
Two-dimensional micromodels for studying the convective dissolution of carbon dioxide in 2D water-saturated porous media
Authors: De Niloy , Singh Naval , Fulcrand Remy , Méheust Yves , Meunier Patrice , Nadal François
Published: October 2022

Convective dissolution is a perennial trapping mechanism of carbon dioxide in geological formations saturated with an aqueous phase.
Exciton tuning in monolayer WSe2viasubstrate induced electron doping
Authors: Pan Yang , Rahaman Mahfujur , He Lu , Milekhin Ilya , Manoharan Gopinath , Aslam Muhammad Awais , Blaudeck Thomas , Willert Andreas , Matković Aleksandar , Madeira Teresa I. , Zahn Dietrich R. T.
Published: October 2022

We report large exciton energy tuning (∼62 meV) in WSe2monolayersviasubstrate induced non-degenerate electron doping.
Non-aromatic azolo[5,1-c][1,2,4]triazines: a pot, atom and step economic (PASE) synthesis, mechanistic insight and fluorescence properties
Authors: Sadchikova Elena V. , Beliaev Nikolai A. , Alexeeva Daria L. , Safronov Nikita E. , Belskaya Nataliya P.
Published: October 2022

An efficient PASE approach to 1,4-dihydroazolo[5,1-c][1,2,4]triazines was developed and new details of the mechanism found. Spectral investigations revealed the dual fluorescence of these compounds both in a diluted solution and in a solid state.
Enhanced peroxidase-like activity of bimetal (Fe/Co) MIL-101 for determination of tetracycline and hydrogen peroxide
Authors: Zhu Baocan , Dong Shanmin , Liu Zhenchao , Gao Yan , Zhu Xixi , Xie Min , Liu Qingyun
Published: October 2022

The peroxidase-like activity of MIL-101(Fe/Co) is improved by adding tetracycline. On the basis of MIL-101(Fe/Co), fast colorimetric sensors of tetracycline and H2O2 have been successfully constructed.
Prediction of stable silver selenide-based energy materials sustained by rubidium selenide alloying
Authors: Chang Yee Hui Robin , Jiang Junke , Yeoh Keat Hoe , Tuh Moi Hua , Chiew Fei Ha
Published: October 2022

Silver selenide (Ag2Se) is a ductile material with a low lattice thermal conductivity that can be a valuable substitute for both PbSe and Bi2Se3 for Pb toxicity free and Bi scarcity.
Crystalline salts of anionic free-base tetrapyrazinoporphyrazines with alkyl-substituents or an extended π-electron system
Authors: Faraonov Maxim A. , Osipov Nikita G. , Romanenko Nikita R. , Kuzmin Alexey V. , Kornev Alexey B. , Stuzhin Pavel A. , Khasanov Salavat S. , Konarev Dmitri V.
Published: October 2022

Anionic crystalline complexes of free-base tetrapyrazinoporphirazines with alkyl- and phenanthrene-substituents have been isolated. Their structures and properties have been studied and discussed.
NIR-II-triggered doxorubicin release for orthotopic bladder cancer chemo-photothermal therapy
Authors: Sun Zhiduo , Zhang Weiyun , Ye Zhichao , Yuan Li , Fu Manli , Liu Xiaoming , Liang Huageng , Han Heyou
Published: October 2022

A 1064 nm laser-triggered gas-driven doxorubicin burst release nanosystem Dox/NH4HCO3@AuHNRs–HTCC (DNAH) was designed for chemo-photothermal combination therapy in orthotopic bladder cancer and could expand applications of controlled drug delivery.
Reusable polymer brush-based photocatalysts for PET-RAFT polymerization
Authors: Bell Kirsten , Freeburne Sarah , Wolford Adam , Pester Christian W.
Published: October 2022

Fluorescein polymer-brush functionalized glass beads synthesize polymersviaphotoelectron reversible addition fragmentation chain transfer (PET-RAFT) polymerization. These shelf stable heterogeneous catalysts can be recycled after simple filtration.
Retraction: Influence of 2-(diisopropylamino)ethyl methacrylate on acid-triggered hydrolysis of cyclic benzylidene acetals and their importance in efficient drug delivery
Authors: Tang Minjie , Yang Zheng , Feng Zujian , Zhou Junhui , Liu Jinjian , Liu Jianfeng , Wang Weiwei , Zhao Junqiang , Dong Anjie , Deng Liandong
Published: October 2022

Retraction of ‘Influence of 2-(diisopropylamino)ethyl methacrylate on acid-triggered hydrolysis of cyclic benzylidene acetals and their importance in efficient drug delivery’ by Minjie Tang et al., Polym. Chem., 2015, 6, 6671–6679, https://doi.org/10.1039/C5PY00734H.
OSCAR: an extensive repository of chemically and functionally diverse organocatalysts
Authors: Gallarati Simone , van Gerwen Puck , Laplaza Ruben , Vela Sergi , Fabrizio Alberto , Corminboeuf Clemence
Published: October 2022

A database of thousands of experimentally-derived or combinatorially enriched organocatalysts and fragments to navigate chemical space and optimize reaction properties.
Coarse-grained modelling to predict the packing of porous organic cages
Authors: Wolpert Emma H. , Jelfs Kim E.
Published: October 2022

This work presents a novel method for predicting molecular crystal structure formation using coarse-grained modelling, enabling the development of design rules.
Supramolecular interactions between ethylene-bridged oligoureas: nanorings and chains formed by cooperative positive allostery
Authors: Tilly David P. , Žabka Matej , Vitorica-Yrezabal Inigo , Sparkes Hazel A. , Pridmore Natalie , Clayden Jonathan
Published: October 2022

Hydrogen-bonded urea oligomers form supramolecular aggregates in the crystalline state. Intermolecular hydrogen bonding generates nano-rings or chains, according to the length and substitution pattern of the oligomers.
Venous endothelial function in cardiovascular disease
Authors: Dardi Patrizia , dos Reis Costa Daniela Esteves Ferreira , Assunção Henrique Charlanti Reis , Rossoni Luciana Venturini
Published: October 2022

The essential role of the endothelium in vascular homeostasis is associated with the release of endothelium-dependent relaxing and contractile factors (EDRF and EDCF, respectively). Different from arteries, where these factors are widely studied, the vasoactive factors derived from the venous endothelium have been given less attention. There is evidence for a role of the nitric oxide (NO), endothelium-dependent hyperpolarization (EDH) mechanism, and cyclooxygenase (COX)-derived metabolites as EDRFs; while the EDCFs need to be better evaluated since no consensus has been reached about their identity in venous vessels. The imbalance between the synthesis, bioavailability, and/or action of EDRFs and/or EDCFs results in a pathological process known as endothelial dysfunction, which leads to reduced vasodilation and/or increased vasoconstriction. In the venous system, endothelial dysfunction is relevant since reduced venodilation may increase venous tone and decrease venous compliance, thus enhancing mean circulatory filling pressure, which maintains or modify cardiac workload contributing to the etiology of cardiovascular diseases. Interestingly, some alterations in venous function appear at the early stages (or even before) the establishment of these diseases. However, if the venous endothelium dysfunction is involved in these alterations is not yet fully understood and requires further studies. In this sense, the present study aims to review the current knowledge on venous endothelial function and dysfunction, and the general state of the venous tone in two important cardiovascular diseases of high incidence and morbimortality worldwide: hypertension and heart failure.
The diverse arsenal of type III CRISPR–Cas-associated CARF and SAVED effectors
Authors: Steens Jurre A. , Salazar Carl Raymund P. , Staals Raymond H.J.
Published: October 2022

Type III CRISPR–Cas systems make use of a multi-subunit effector complex to target foreign (m)RNA transcripts complementary to the guide/CRISPR RNA (crRNA). Base-pairing of the target RNA with specialized regions in the crRNA not only triggers target RNA cleavage, but also activates the characteristic Cas10 subunit and sets in motion a variety of catalytic activities that starts with the production of cyclic oligoadenylate (cOA) second messenger molecules. These messenger molecules can activate an extensive arsenal of ancillary effector proteins carrying the appropriate sensory domain. Notably, the CARF and SAVED effector proteins have been responsible for renewed interest in type III CRISPR–Cas due to the extraordinary diversity of defenses against invading genetic elements. Whereas only a handful of CARF and SAVED proteins have been studied so far, many of them seem to provoke abortive infection, aimed to kill the host and provide population-wide immunity. A defining feature of these effector proteins is the variety of in silico-predicted catalytic domains they are fused to. In this mini-review, we discuss all currently characterized type III-associated CARF and SAVED effector proteins, highlight a few examples of predicted CARF and SAVED proteins with interesting predicted catalytic activities, and speculate how they could contribute to type III immunity.
Characterising ion channel structure and dynamics using fluorescence spectroscopy techniques
Authors: Bhat Shreyas , Blunck Rikard
Published: October 2022

Ion channels undergo major conformational changes that lead to channel opening and ion conductance. Deciphering these structure-function relationships is paramount to understanding channel physiology and pathophysiology. Cryo-electron microscopy, crystallography and computer modelling provide atomic-scale snapshots of channel conformations in non-cellular environments but lack dynamic information that can be linked to functional results. Biophysical techniques such as electrophysiology, on the other hand, provide functional data with no structural information of the processes involved. Fluorescence spectroscopy techniques help bridge this gap in simultaneously obtaining structure-function correlates. These include voltage-clamp fluorometry, Förster resonance energy transfer, ligand binding assays, single molecule fluorescence and their variations. These techniques can be employed to unearth several features of ion channel behaviour. For instance, they provide real time information on local and global rearrangements that are inherent to channel properties. They also lend insights in trafficking, expression, and assembly of ion channels on the membrane surface. These methods have the advantage that they can be carried out in either native or heterologous systems. In this review, we briefly explain the principles of fluorescence and how these have been translated to study ion channel function. We also report several recent advances in fluorescence spectroscopy that has helped address and improve our understanding of the biophysical behaviours of different ion channel families.
High‐frequency common‐mode voltage mitigation for current‐source inverter in transformerless photovoltaic system using active zero‐state space vector modulation
Authors: Gao Hang
Published: October 2022

Space vector modulation (SVM) schemes with leakage current mitigation capability for current‐source inverters (CSIs) in transformerless photovoltaic (PV) systems have not been well explored yet. In this study, the advantage of a special SVM scheme, called active zero‐state SVM (AZS‐SVM), on suppressing high‐order harmonics in the common‐mode voltage (CMV) is revealed and theoretically analysed, since the high‐frequency components in the CMV have decisive impacts on the generated leakage current. A five‐segment sequence is proposed for AZS‐SVM applied for CSIs. Both simulation and experiments are conducted on a (2.5 kW/208 V/6.94 A) grid‐connected three‐phase CSI, which validates the effectiveness of the designed AZS‐SVM to mitigate the CMV high‐order harmonics when compared to that by conventional SVM under different operating conditions.
Neue Technologien in der Mikrochirurgie: Potential, Indikationen und
ökonomische Aspekte – Konsensus-Bericht der Deutschsprachigen
Arbeitsgemeinschaft für Mikrochirurgie der peripheren Nerven und
Gefäße (DAM)
Authors: Kueckelhaus Maximilian , Kolbenschlag Jonas , Kirschniak Andreas , Beier Justus P. , Enzinger Simon , Harder Yves , Kneser Ulrich , Lehnhardt Marcus , Rab Matthias , Daigeler Adrien
Published: October 2022

Kürzlich haben mehrere neue Technologien zur Unterstützung von
Mikrochirurg:innen eine europäische Marktzulassung erhalten. Der
vorliegende Artikel fasst die Eindrücke eines Expertenpanels zur
Einordnung des Potentials neuer Technologien im Hinblick auf Nutzen für
den Operateur, spezifische Indikationen und ökonomische Aspekte
während der 42. Jahrestagung der Deutschsprachigen Arbeitsgemeinschaft
für Mikrochirurgie der peripheren Nerven und Gefäße
(DAM) in Graz, Österreich zusammen und diskutiert diese. Das
Expertengremium befasste sich im Allgemeinen mit den Grundsätzen und
Voraussetzung der erfolgreichen Etablierung neuer Technologien und im Speziellen
mit neuartigen optischen und robotischen Systemen. Dazu wurde die aktuelle
wissenschaftliche Literatur aufgearbeitet sowie anfängliche klinische
Erfahrungswerte im Rahmen von Fallserien und retrospektiven Studien durch die
Mitglieder des Expertenpaneels präsentiert. In der sich
anschließenden Diskussion wurde herausgearbeitet, dass zunächst
eine Identifizierung von Patienten-Untergruppen notwendig sein wird, bei denen
mit dem Einsatz der neuen Technologien am ehesten ein klinischer Nutzen zu
erzielen sei. Da bereits eine klinische Zulassung einiger Systeme gegeben ist,
kann bei der unmittelbaren klinischen Anwendung eine Vorgehensweise von
möglichst einfachem Einsatz hin zu immer feineren Anwendungen, also von
der Mikro- bis hin zur Supermikrochirurgie, hin entwickelt werden. Eine
Finanzierung kostenintensiver Systeme sei zunächst vermutlich nicht
über den Erlös aus der Regelversorgung, sondern nur durch
Fördergelder oder subventionierte klinische Studien möglich. In
einer abschließenden Befragung sieht die Mehrheit der
Sitzungsteilnehmenden die Notwendigkeit einer Preisreduktion sowohl der
Technologien zur Visualisierung als auch der Operationsrobotik, um eine
flächendeckende klinische Etablierung zu ermöglichen. Ebenfalls
eine Mehrheit der Teilnehmenden würde bei klinischem Einsatz eine
Kombination aus Exoskop bzw. robotischem Mikroskop und einem Operationsroboter
bevorzugen. Die vorliegende Konsensusarbeit adressiert die Entwicklung einer
Strategie zur effektiven Etablierung neuer Technologien, die die operative
Qualität ausgewählter Eingriffe weiter erhöhen soll.
The Cost Effectiveness of Unicompartmental versus Total Knee Arthroplasty
Authors: Varughese Ibin , Whitehouse Sarah L. , Donnelly William J. , Crawford Ross W.
Published: October 2022

This study examines the potential cost savings for the health system and the community in a broadly accessible model through the increased utilization of unicompartmental knee arthroplasty (UKA) using robotic arm-assisted UKA (raUKA) versus conventional total knee arthroplasty (cTKA). We retrospectively reviewed 240 patients where the first 120 consecutive raUKA performed during this period were matched to 120 cTKAs. Clinical data from the medical records and costs for procedure for each component were collected. Bivariate analyses were performed on the data to determine if there were statistically significant differences by surgery type in clinical outcomes and financial costs. There was a significantly lower cost incurred for raUKA versus cTKA with an average saving of AU$7,179 per case. The operating time (86.0 vs. 75.9 minutes; p = 0.004) was significantly higher for raUKA, but the length of stay was significantly lower (1.8 vs. 4.8 days; p < 0.001). There was a significant difference in the use of opioids between raUKA and cTKA (125.0 morphine equivalent [ME] vs. 522.1 ME, p < 0.001). This study demonstrated that the use of raUKA rather than cTKA in suitably indicated patients may realize significant cost savings.
Modeling sloshing fuel tanks to provide oscillatory damping for airplane wings
Authors: Thompson Avery
Published: October 2022

Damping via fuel tanks could allow for lighter wing structures, but the complex flow behavior can be challenging to study.
Diode stretches capabilities of ionotronics
Authors: Patrick Chris
Published: October 2022

An ionoelastomer junction is more stretchable than its predecessors, bringing ionotronics closer to applications in human-machine interfaces, soft robotics, and bionic prosthetics.
Wake flame combustion found to result from vortex shedding
Authors: Green Leigh Ann
Published: October 2022

The microscopic burning mechanism of fuel droplets is revealed through the scaling laws of fluid dynamics.
Dense hydrous silica could carry water to Earth’s mantle
Authors: Piccone Ashley
Published: October 2022

The deep water cycle may alter mantle properties and regulate surface reservoirs.
Effects of background noise on fit parameters of plasma scattering angle distributions
Authors: Nicolaou Georgios , Allegrini Frederic , Livadiotis George , Ebert Robert W.
Published: October 2022

The presence of noise in plasma particle measurements by scientific instruments causes inaccuracies in the determined plasma bulk parameters. This study demonstrates and evaluates the effects of noise in the determination of typical distribution functions describing the scattering angles of plasma particles passing through thin foils. First, we simulate measurements of plasma particles passing through a thin carbon foil, considering that their scattering angles follow kappa-like distribution functions, as being addressed in previous studies. We work with these specific distributions because we can produce them in the laboratory. We add Poisson-distributed background noise to the simulated data. We fit the simulated measurements and compare the fit parameters with the input parameters. As expected, we find that the discrepancy between the initial parameters and those derived from the fits increases with the relative increase of the noise. The misestimations exhibit characteristic trends as functions of the signal-to-noise ratio and the input parameters. Second, we examine the scattering angle distributions measured with a laboratory experiment of protons passing through a thin carbon foil for different signal-to-noise ratios. These measurements support the simulation results, although they exhibit a larger discrepancy than found in the simulations. Finally, we discuss how we can improve the accuracy of estimated distribution parameters in space and ground-based applications by excluding data-points from the tails of the distribution functions. Although our results exhibit the effects of noise in a specific type of distribution functions, we explain that this technique can be applied to and optimized for other specific data-sets.
Deposited layer substrate (DeLaS)—A module for radiation measurement
Authors: Pandya Shwetang N. , Pandya Santosh P. , Rayjada P. A. , Govindarajan Jagannathan
Published: October 2022

Infrared Imaging Video Bolometer (IRVB) measures the radiation from plasma in two-dimensions. IRVB uses a few micrometer thick metal foil as a radiation absorber. The foil being ultra-thin has several limitations. A new radiation absorbing module is proposed here that can effectively overcome the shortcomings of the foils used in IRVB. This module is developed by depositing carbon and metal thin films on an infrared transmitting substrate using magnetron sputtering. This patented module is termed Deposited Layer on a Substrate. A prototype is developed and laboratory tests are carried out using a laser source to demonstrate its feasibility as a radiation detector. The advantages of this module over conventional foils, its development, and experimental results validating the concept are discussed in this article.
Nonadiabatic transition paths from quantum jump trajectories
Authors: Anderson Michelle C. , Schile Addison J. , Limmer David T.
Published: October 2022

We present a means of studying rare reactive pathways in open quantum systems using transition path theory and ensembles of quantum jump trajectories. This approach allows for the elucidation of reactive paths for dissipative, nonadiabatic dynamics when the system is embedded in a Markovian environment. We detail the dominant pathways and rates of thermally activated processes and the relaxation pathways and photoyields following vertical excitation in a minimal model of a conical intersection. We find that the geometry of the conical intersection affects the electronic character of the transition state as defined through a generalization of a committor function for a thermal barrier crossing event. Similarly, the geometry changes the mechanism of relaxation following a vertical excitation. Relaxation in models resulting from small diabatic coupling proceeds through pathways dominated by pure dephasing, while those with large diabatic coupling proceed through pathways limited by dissipation. The perspective introduced here for the nonadiabatic dynamics of open quantum systems generalizes classical notions of reactive paths to fundamentally quantum mechanical processes.
The spontaneous polarization of In-doped κ-Ga2O3 by first-principles calculation
Authors: Zhang Fabi , Liu Xu , Zhou Juan , Liao Qing , Sun Tangyou , Liu Xingpeng , Peng Ying , Guo Daoyou , Wang Peng , Li Haiou
Published: October 2022

The crystal structure, band structure, density of states, and optical properties of κ-(Ga1−xInx)2O3 (x = 0, 0.125, 0.25, 0.5) were studied using the first-principles calculation based on the density functional theory. With the increase of In content x, the bandgap of κ-(Ga1−xInx)2O3 decreases, while the light absorption coefficient increases. The spontaneous polarization of κ-(Ga1−xInx)2O3 was calculated qualitatively using the Born effective charge. The results suggested that κ-(Ga1−xInx)2O3 is also a material with spontaneous polarization properties. The spontaneous polarization in the extended c-axis has increased 1.27 times, from 27.31 to 34.58 μC/cm2, with the increase of In content from 0 to 0.5. This work paves the way for modulating spontaneous polarization of wide bandgap semiconductors. It provides a theoretical basis for the potential application of κ-(Ga1−xInx)2O3 in high electron mobility transistors, quantum well-infrared photodetectors, and photovoltaic materials.
Multiterminal epitaxial tungsten nanostructures on MgO/GaAs(001) substrates: Temperature effects in ballistic electron transport
Authors: Mikhailov G. M. , Chernykh A. V. , Malikov I. V. , Fomin L. A.
Published: October 2022

High-quality single-crystalline multiterminal tungsten nanostructures were fabricated on MgO/GaAs (001) substrates using subtractive lithography. Single-crystalline tungsten films with a thickness of d = 80 nm and low roughness were grown using sequential epitaxy of MgO (001) and W (001) layers on GaAs (001) via pulsed laser deposition. The temperature dependence of bridge-type nanostructure electron conductivity indicates that they are high-quality metal conductors. The electron mean free path reached 760 nm at low temperatures and was approximately an order of magnitude greater than the tungsten film thickness. Strong non-local effects resulting from ballistic electron transport were observed in the multiterminal cross-type W (001) nanostructures with an arm width Wc = 400 nm below T = 80 K. Such effects can be explained by the exponential damping of ballistic properties of nanostructures as a function of the electron mean free path in the wide temperature range 4.2–100 K. Simulations predict that the ballistic effects in such nanostructures can be significant even at room temperature with an arm width approaching 10 nm and a size ratio of Wc/d ∼ 1.
Space charge characteristics in epoxy/nano-MgO composites: Experiment and two-dimensional model simulation
Authors: Liu Peng , Pang Xi , Xie Zongliang , Xu Tianlei , Shi Shifeng , Wu Peng , Li He , Peng Zongren
Published: October 2022

Space charge accumulation in polymer dielectrics may lead to serious electric field distortion and even insulation failure during long-term operations of power equipment and electronic devices, especially under conditions of high temperature and direct current electric stress. The addition of nanoparticles into polymer matrices has been found effective in suppressing space charge accumulation and alleviating electric field distortion issues. Yet, the underlying mechanisms of nanoparticle doping remain a challenge to explore, especially from multi-dimensional composite insights. Here, a two-dimensional bipolar charge transport model with consideration of interface zones between organic/inorganic phases is proposed for the investigation into space charge behaviors of nanodielectrics. To validate the effectiveness and feasibility of the model, pulsed electroacoustic experiments are performed on epoxy/nano-MgO composites with different doping ratios of nanoparticles. Experimental observations match well with simulation anticipations, i.e., higher doping ratios of nanoparticles below the percolation threshold exhibit better capabilities to inhibit space charge accumulation. The deep traps (∼1.50 eV) generated in the interface zones are demonstrated to capture free charges, forming a reverse electric field in the region adjacent to electrodes and impeding the space charge migration toward the interior of the composite. This model is anticipated to provide theoretical insight for understanding space charge characteristics in polymer nanodielectrics and computing charge dynamics in extreme conditions where experiments are challenging to perform.
Magnetoelectric coupling coefficient in multiferroic capacitors: Fact vs Artifacts
Authors: Hassanpour Amiri Morteza , Sharifi Dehsari Hamed , Asadi Kamal
Published: October 2022

Multiferroic materials are characterized by their magnetoelectric coupling coefficient, which can be obtained using a lock-in amplifier by measuring the voltage developed across a multiferroic capacitor in a time-variable magnetic field, Hac cos(ωt), where Hac and ω are the amplitude and frequency of the applied magnetic field. The measurement method, despite its simplicity, is subject to various parasitic effects, such as magnetic induction, which leads to significant over-estimation of the actual magnetoelectric response. This article outlines the measurement theory for a multiferroic capacitor using the lock-in technique. It is demonstrated that the inductive contribution has linear proportionality with Hac, ω, and Hacω. It is shown that the true magnetoelectric coupling response is retrieved from the real component of the lock-in signal. Using a polymer-nanoparticle multiferroic composite, the internal consistency of the proposed measurement method is experimentally demonstrated, and it is shown that the actual multiferroic signal can be retrieved using the lock-in technique by removing the magnetic induction contribution from the signal. It is observed that the magnetoelectric voltage shows only a linear dependence with Hac, a saturating behavior with ω, and Hacω. Furthermore, a measurement protocol for reliable reporting of magnetoelectric coupling coefficient has been provided.
Numerical investigation of flexible Purcell-like integrated microfluidic pumps
Authors: Binsley Jacob L. , Pagliara Stefano , Ogrin Feodor Y.
Published: October 2022

Integrating miniature pumps within microfluidic devices is crucial for advancing point-of-care diagnostics. Understanding the emergence of flow from novel integrated pumping systems is the first step in their successful implementation. A Purcell-like elasto-magnetic integrated microfluidic pump has been simulated in COMSOL Multiphysics and its performance has been investigated and evaluated. An elastic, cilia-like element contains an embedded magnet, which allows for actuation via a weak, uniaxial, sinusoidally oscillating, external magnetic field. Pumping performance is correlated against a number of variables, such as the frequency of the driving field and the proximity of the pump to the channel walls, in order to understand the emergence of the pumping behavior. Crucially, these simulations capture many of the trends observed experimentally and shed light on the key interactions. The proximity of the channel walls in the in-plane direction strongly determines the direction of net fluid flow. This characterization has important implications for the design and optimization of this pump in practical applications.
Influence of air and water vapor on EEDF, plasma parameters, and the main RONS in atmospheric pressure low temperature helium plasmas: Global model approach
Authors: Mladenović Željko , Gocić Saša
Published: October 2022

A zero-dimensional global model is developed with an aim to study the influence of air and water vapor on an electron energy distribution function, electron density, and temperature as well as on the chemical composition of atmospheric pressure helium plasmas, with special focus on the main reactive oxygen and nitrogen species important for applications of low temperature plasmas. The main channels for the production and consumption of electrons and electron energy gain and loss are examined by a global model based on a parametric study with variations of the mole fractions of air and water vapor. The calculations are done for 100, 1000, and 10 000 ppm of air in plasma, and for each of these values, the content of water vapor is taken to be 100, 1000, 2000, …, to 10 000 ppm. The variations of the most important production and consumption processes for reactive oxygen and nitrogen species are analyzed in detail. According to the results presented in this paper, water vapor highly contributes to electronegativity of the plasma through pronounced attachment of electrons, which then leads to an increase in electron temperature. For high water vapor content, vibrational excitations of water molecules are one of the main electron energy loss processes, leading to a further effect on the plasma composition. Water decreases concentrations of atomic oxygen, nitrogen, and ozone, while there is an increase in nitrogen oxide, OH, H2O2, and HO2 concentrations. Cross-sectional data for electron scattering on ground and excited state neutrals are mainly taken from the Quantemol-DB database.
Chirality-dependent roughness of magnetic domain walls
Authors: Yu Ji-Sung , Kim Dae-Yun , Moon Joon , Lee Seong-Hyub , Chang Jun-Young , Kim Duck-Ho , Min Byoung-Chul , Choe Sug-Bong
Published: October 2022

Dzyaloshinskii–Moriya interaction (DMI) plays a key role in the formation and stability of chiral magnetic objects, such as skyrmions and chiral domain-walls (DWs), which are used as building blocks of emerging high-density and high-speed devices. Here, we demonstrate that the DMI determines also the roughness of chiral DWs. Such DMI-dependent chiral roughness was observed from magnetic multilayer films of the Pt/Co/Pt heterostructure. Despite the stochastic nature of the DW roughness, the films clearly showed the roughness variation with respect to the DW chirality in balance with the DMI. The present analysis of the DW roughness offers a way to quantitatively determine the DMI-induced effective field as an essential parameter for the stability and dynamic characteristics of chiral DWs.
Improving performances of oxide solid electrolytes by a magnetic field for all-solid-state lithium-metal batteries
Authors: Zhang Yining , Chen Shaojie , Zhang Yue , Yu Yi , Liu Wei
Published: October 2022

All-solid-state lithium-metal batteries have been regarded as the next-generation energy storage due to the potential high safety and high energy density. However, for oxide solid electrolytes (SEs), the relatively low ionic conductivities and the growth of lithium dendrite leading to safety issues limit their commercialization. Here, we systematically investigate the influences of external magnetic field on electrochemical performances of oxide SEs. It reveals that the magnetic field can improve ionic conductivity of SEs and the cycle performance in Li symmetric cells. The enhanced performance is because the magnetohydrodynamics effect can promote diffusion in SEs and homogenize distribution of lithium deposition to avoid the propagation of lithium dendrite. This strategy can be extent to other types of SEs or various energy applications.
Applications of wall-models to implicit large eddy simulations in the spectral/hp element method
Authors: Huang Bohua , Wang Rui , Wu Feng , Xu Hui
Published: October 2022

An implicit large eddy simulation (iLES) method based on a spectral vanishing viscosity (SVV) method has been well established in the framework of the spectral/hp element method (which is called the SVV-iLES method), and the SVV regularization introduces proper dissipation to the numerical scheme, which in turn reduces the truncation error and the uncertainty in computation. However, SVV-iLES is still limited to moderate Reynolds numbers due to the huge computational cost in resolving the inner part of the boundary layer. By modeling the near-wall layer, a wall-model coupling strategy, tailored to the features of the SVV-iLES, is proposed to substantially reduce the computational cost. This work is the first to construct the wall model of SVV-iLES based on the spectral/hp element method, and the practice rules can be regarded as guidelines for the application of the wall model to iLES with high order schemes. Numerical investigations for a well-established benchmark problem of the turbulent channel flow are implemented by the proposed wall-modeled SVV-iLES. The results obtained are consistent with the reference direct numerical simulation (DNS) data at different Reynolds numbers considered. The effect of the time-averaged velocity at the matching interface is examined, and the results suggest that the instantaneous velocity can be directly used in the algebraic wall-model, which in turn could speed up the computation. Additionally, a comparison between the classical log-law and Reichardt's law models reveals that there are no significant differences in statistical quantities in the logarithmic region. Finally, it was found that, at similar grid resolution, the p-type refinement shows better agreement with the reference DNS results.
Superflexibility in single-crystalline manganite oxide membranes with gigantic bending curvature and strain
Authors: Lu Qinwen , Wang Qing , Yang Qun , Cheng Long , Zhai Xiaofang
Published: October 2022

High-quality flexible membranes have promoted a myriad of applications in soft electronics or spintronic devices. Nevertheless, magnetic membranes that can withstand strong folding and rolling distortions have rarely been reported. Here, we found that the few to tens of nanometer thick LaMnO3 membranes with single-crystalline qualities exhibit superflexibility, demonstrated by self-folding and rolling into few-micron and sub-micron features. The combined scanning transmission electron microscope and selected area electron diffraction experiments simultaneously confirm the 180° folded single crystalline structure and the associated bending curvature and strain as large as 2 μm−1 and 4%. Furthermore, the scanning electron microscope revealed that as the membrane thickness decreases from 40 to 20 nm and 8 nm, the 180° folding is replaced by self-rolling into few-micron size tubes. Magnetization measurements revealed a large saturation (remnant) magnetization enhancement of 21% (34%) achieved in a macroscopically forced bending state under a similar bending strain of 4.9%. This work demonstrates the superflexibility of manganite oxide membranes which promise superior potential in flexible magnetic device applications.
Gas permeation rates of ultrathin graphite sealed SiO2 cavities
Authors: Liu Yan-Xin , Ambjørner Hjalte Rørbech , Bonczyk Tobias G. , Dollekamp Edwin , Kaas Lau M. , Vesborg Peter C. K.
Published: October 2022

Despite the proven impermeability of graphene toward most standard gases, graphene/graphite sealed SiO2 cavities always exhibit a nonzero leak rate, and the physical leakage mechanism is still unclear. By measuring leak rates of different gases for the same cavities sealed by ultrathin graphite under identical conditions, we find that the leak rates generally depend on the kinetic diameter of the gas molecules, which implies that the leakage is caused by a molecular sieving mechanism. By comparing different samples, we find that the leak rate of any gas in a particular sample is well predicted by the leak rate of N2 in that sample. In addition, we observe enhanced leak rates of water-soluble molecules. We infer that the leakage path (i.e., the graphene/graphite–SiO2 interface) favors hydrophilic species.
Significant regulation of stress on the contribution of optical phonons to thermal conductivity in layered Li2ZrCl6: First-principles calculations combined with the machine-learning potential approach
Authors: Wu Cheng-Wei , Ren Xue , Li Shi-Yi , Zeng Yu-Jia , Zhou Wu-Xing , Xie Guofeng
Published: October 2022

The layered solid electrolyte Li2ZrCl6 and Li metal electrodes have a very good contact stability, but the thermal transport properties of Li2ZrCl6 are still unclear. Here, we systematically study the intrinsic lattice thermal conductivity (κp) of Li2ZrCl6 using the machine-learning potential approach based on first-principles calculations combined with the Boltzmann transport theory. The results show that the κp of Li2ZrCl6 at room temperature is 3.94 W/mK along the in-plane (IP) direction and 1.05 W/mK along the out-plane (OP) direction, which means that the κp is significantly anisotropic. In addition, under the compressive stress in the OP direction, the κp evolution along the IP and OP directions exhibits completely different trends, because the stress has a significant regulatory effect on the contribution of optical phonons to κp. With the increase in stress, the κp in the IP direction monotonically decreases, while the κp in the OP direction increases by a factor of 2.2 under a compressive strain of 13%. This is because the contribution of low-frequency optical phonons to κp in the IP direction is as high as 58% when no stress is applied, and this contribution is significantly suppressed with increasing compressive strain. However, the contribution of optical phonons in the OP direction to the κp increases with the increase in stress. Our results reveal the thermal transport properties of Li2ZrCl6 and the effect of the compressive strain on the κp of Li2ZrCl6, thereby providing a reference for the use of Li2ZrCl6 in Li-metal batteries.
Classification of spatial-temporal flow patterns in a low Re wake based on the recurrent trajectory clustering
Authors: Wu Huixuan , Zhang Meihua , Zheng Zhongquan Charlie
Published: October 2022

Coherent structures are ubiquitous in unsteady flows. They can be regarded as certain kinds of spatial-temporal patterns that interact with the neighboring field. Although they play a key role in convection and mixing, there is no consensus on how to define them, and their dynamics are complicated. In the past decades, many methods are developed to identify coherent structures based on instantaneous velocity fields (e.g., vortex identification) or long-time statistics (e.g., proper orthogonal decomposition), but the evolution process of individual structures is not well considered in the identification. In this paper, we propose a new method to classify coherent motions according to their evolution dynamics. Specifically, the evolutions are represented by trajectories in the phase space. We define a distance between two trajectories and use it to construct a network that characterizes all evolution patterns. Using spectrum clustering, we categorize these patterns into various groups. This method is applied to a low Reynolds number wake flow downstream of two cylinders-in-tandem, where one of the cylinders oscillates in the transverse direction. The flow is quasi-periodic, and four types of recurrent spatial-temporal patterns can be identified. It is a useful tool to investigate low Reynolds number unsteady flows.
Numerical study of a hollow pileup yielded by deposition of successive hollow droplets
Authors: Vu Truong V. , Ho Nang X.
Published: October 2022

Understanding the pileup formation process of sequentially deposited droplets is vital in advancing droplet-based printing technologies. While pileups of simple droplets have been extensively studied, knowledge of the hollow pileup formation is inadequate. This paper presents a fully resolved numerical analysis of the pileup formed by successively depositing incoming hollow droplets on a pre-solidified (or base) droplet on a supercool surface. An axisymmetric front-tracking method is used to handle the simulations. The pileup height increases as the incoming droplets coalesce, while the hollow cores may or may not merge. The pileup shape and its hollow configuration depend on parameters such as the Stefan number, Peclet number, Weber number, Fourier number, and the size and number of hollow cores. Varying these parameters does not affect the peak formation at the top of the pile caused by volume expansion during phase change, although the Fourier number has a strong influence on the mean aspect ratio and solidification time of the pileup. Increasing the deposition rate enhances the coalescence of hollow cores and reduces the mean aspect ratio of the pileup. Reducing the Stefan number also promotes hollow core coalescence, which decreases the mean aspect ratio. However, the size of the hollow core and the Peclet and Weber numbers have almost no influence on the outer shape of the hollow pileup. The effect of the number of incoming droplets on the pileup formation is also revealed.
Intra and intercellular signals governing sperm maturation
Authors: Belleannée Clémence , Viana Arabela Guedes De Azevedo , Lavoie-Ouellet Camille
Published: October 2022

After their production in the testis, spermatozoa do not have the capacity to move progressively and are unable to fertilise an oocyte. They sequentially acquire these abilities following their maturation in the epididymis and their capacitation/hyperactivation in the female reproductive system. As gene transcription is silenced in spermatozoa, extracellular factors released from the epididymal epithelium and from secretory glands allow spermatozoa to acquire bioactive molecules and to undergo intrinsic modifications. These modifications include epigenetic changes and post-translational modifications of endogenous proteins, which are important processes in sperm maturation. This article emphasises the roles played by extracellular factors secreted by the epididymis and accessory glands in the control of sperm intercellular signallings and fertilising abilities.
A robust core architecture of functional brain networks supports topological resilience and cognitive performance in middle- and old-aged adults
Authors: Stanford William C. , Mucha Peter J. , Dayan Eran
Published: October 2022

Aging is associated with gradual changes in cognition, yet some individuals exhibit protection against age-related cognitive decline. The topological characteristics of brain networks that promote protection against cognitive decline in aging are unknown. Here, we investigated whether the robustness and resilience of brain networks, queried via the delineation of the brain’s core network structure, relate to age and cognitive performance in a cross-sectional dataset of healthy middle- and old-aged adults (
n
= 478, ages 40 to 90 y). First, we decomposed each subject’s functional brain network using
k
-shell decomposition and found that age was negatively associated with robust core network structures. Next, we perturbed these networks, via attack simulations, and found that resilience of core brain network nodes also declined in relationship to age. We then partitioned our dataset into middle- (ages 40 to 65 y,
n
= 300) and old- (ages 65 to 90 y,
n
= 178) aged subjects and observed that older individuals had less robust core connectivity and resilience. Following these analyses, we found that episodic memory was positively related to robust connectivity and core resilience, particularly within the default node, limbic, and frontoparietal control networks. Importantly, we found that age-related differences in episodic memory were positively related to core resilience, which indicates a potential role for core resilience in protection against cognitive decline. Together, these findings suggest that robust core connectivity and resilience of brain networks could facilitate high cognitive performance in aging.