bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct C–C bond scission of xylitol to ethylene and propylene glycol precursors using single-atom catalysts (SACs) anchored on MgO
Authors: Akpe Shedrack G. , Choi Sun Hee , Ham Hyung Chul
Published: May 2023

Shorter chain alcohols, as opposed to longer ones, are beneficial as biomass feedstock for chemicals and fuels, including hydrogen production. More so, it has been demonstrated that carbon–carbon rather than carbon–oxygen bond-cleaving activity determines the product selectivity of a metal catalyst for higher oxygenates reforming. In this report, we investigate the direct C2–C3 bond-cleaving activity of xylitol via first-principles, periodic density functional theory calculations to identify the differences in activities between single-crystal catalysts (SCCs) and single-atom catalysts (SACs). A comparison of the kinetic barriers revealed that xylitol's C–C bond scission appears to be a near-impossible task on SCCs. However, SACs demonstrated higher performance. For example, Ir1/MgO and Ir1/MgO_Ovac (having surface oxygen vacancy) yielded ∼72% and 54% decrease, respectively, in Gibb’s free activation energy compared to Ir (111) at the xylitol reforming operating temperature of 473 K. Furthermore, electronic structure calculations revealed an up-shift in the DOS for the surface M1 atoms in all investigated SACs compared to the surface atoms of their respective SCCs, resulting in M1 higher d-band center and stronger adsorbate (s) binding. This study highlights the importance of SACs for boosting the atom efficiency of costly metals while also offering a new strategy for tuning the activity of catalytic reactions.
Chimera states in multiplex networks: Chameleon-like across-layer
synchronization
Authors: Andrzejak Ralph G. , Espinoso Anaïs
Published: May 2023

Different across-layer synchronization types of chimera states in multilayer networks have been discovered recently. We investigate possible relations between them, for example, if the onset of some synchronization type implies the onset of some other type. For this purpose, we use a two-layer network with multiplex inter-layer coupling. Each layer consists of a ring of non-locally coupled phase oscillators. While oscillators in each layer are identical, the layers are made non-identical by introducing mismatches in the oscillators’ mean frequencies and phase lag parameters of the intra-layer coupling. We use different metrics to quantify the degree of various across-layer synchronization types. These include phase-locking between individual interacting oscillators, amplitude and phase synchronization between the order parameters of each layer, generalized synchronization between the driver and response layer, and the alignment of the incoherent oscillator groups’ position on the two rings. For positive phase lag parameter mismatches, we get a cascaded onset of synchronization upon a gradual increase of the inter-layer coupling strength. For example, the two order parameters show phase synchronization before any of the interacting oscillator pairs does. For negative mismatches, most synchronization types have their onset in a narrow range of the coupling strength. Weaker couplings can destabilize chimera states in the response layer toward an almost fully coherent or fully incoherent motion. Finally, in the absence of a phase lag mismatch, sufficient coupling turns the response dynamics into a replica of the driver dynamics with the phases of all oscillators shifted by a constant lag.
The influence of wind on the evolution of two random wavetrains on deep water
Authors: Halder Sourav , Dhar A. K.
Published: May 2023

We have studied the effect of randomness on the stability of interfacial gravity waves on deep water in the presence of uniform wind flow. The fourth-order nonlinear evolution equations for two Stokes wavetrains are used here to obtain the wave-kinetic equations for narrow-band of gravity wavetrains. Employing these kinetic equations we have then made the stability analysis of two initially homogeneous Lorentz form of wave spectra subject to infinitesimal perturbations. The effect of randomness is observed to reduce the growth rate and the extent of the instability region. The key result of the present analysis is that the fourth-order terms in the evolution equations significantly modify the modulational instability properties and produce a decrease on the growth rate. It is found that the growth rate of instability increases due to the effect of wind velocity.
Direction-dependent noise-induced synchronization in mobile oscillators
Authors: Shajan Emilda , Ghosh Dibakar , Kurths Jürgen , Shrimali Manish Dev
Published: May 2023

Synchronization among uncoupled oscillators can emerge when common noise is applied on them and is famously known as noise-induced synchronization. In previous studies, it was assumed that common noise may drive all the oscillators at the same time when they are static in space. Understanding how to develop a mathematical model that apply common noise to only a fraction of oscillators is of significant importance for noise-induced synchronization. Here, we propose a direction-dependent noise field model for noise-induced synchronization of an ensemble of mobile oscillators/agents, and the effective noise on each moving agent is a function of its direction of motion. This enables the application of common noise if the agents are oriented in the same direction. We observe not only complete synchronization of all the oscillators but also clustered states as a function of the ensemble density beyond a critical value of noise intensity, which is a characteristic of the internal dynamics of the agents. Our results provide a deeper understanding on noise-induced synchronization even in mobile agents and how the mobility of agents affects the synchronization behaviors.
Threshold density for toroidal rotation reversal bifurcation induced by symmetry breaking
Authors: Li Hanhui , Sun Youwen , Wang Lu
Published: May 2023

Threshold density for intrinsic toroidal rotation reversal is studied using a newly proposed model [Li et al., Nucl. Fusion 61, 104002 (2021)] based on the neoclassical toroidal plasma viscosity (NTV) effect induced by symmetry breaking due to the existence of internal kink mode. In this model, rotation reversal happens when the NTV steady state flow jumps between “electron root” and “ion root,” which depends on plasma collisionality regimes. To make it convenient for cross machine comparisons or extrapolation to the future device, a scaling of threshold density for rotation reversal is proposed based on the physics of transition between the 1/ν and superbanana plateau regimes, i.e., the normalized collisionality over the particle toroidal precessional frequency rather than over the particle bounce frequency that is frequently used in neoclassical theory. The theoretical scaling of the threshold density on electron temperature and magnetic field strength is well verified by the NTVTOK modeling. Other effects, such as boundary condition, temperature gradient, and temperature ratio, which cannot be included in the theoretical scaling, are also investigated by using the NTVTOK modeling.
Strong influence of the surrounding gas in laser-spot lock-in thermography
Authors: Salazar Agustín , Mendioroz Arantza , Rodríguez-Valdés Félix , Bedoya Adrián , Marín Ernesto , García-Segundo Crescencio
Published: May 2023

In laser-spot lock-in thermography, the amplitude of the surface temperature decreases monotonically with the distance to the laser spot. This radial decrease is commonly used to measure the in-plane thermal diffusivity of the sample. However, in the case of thermal insulators, an unpredicted and abrupt slope change appears in the radial profiles. In this work, we first demonstrate that heat conduction to the air surrounding the sample is the cause of this unexpected behavior. Then, we take advantage of this slope change to retrieve simultaneously in-plane thermal diffusivity and conductivity of thermal insulators.
Prediction of chemical bond breaking in insensitive high-energy energetic materials at high temperature and pressure
Authors: Li Wen-Guang , Hong Dan , Li Xing-Han , Chang Xiang-Hui , Liu Zheng-Tang , Liu Qi-Jun
Published: May 2023

The bond breaking of energetic materials under the action of temperature and pressure has always been a key step in understanding the explosive mechanism of energetic materials. In this work, we use the mean square shift of atoms and the theoretical bond breaking position of chemical bonds to give the bond breaking temperature of each chemical bond of insensitive high-energy energetic materials, 1,1-diamino-2,2-dinitroethylene (α-FOX-7) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB), at 0 and 30 GPa. The calculation results show that the bond breaking sequence of α-FOX-7 and TATB in the selected pressure range is N–H, N–O, C–NO2, and C–NH2. At the same time, the difference in the sensitivity between α-FOX-7 and TATB was discussed through the analysis of partial chemical bond breaking temperature.
Decoupling the interplay of polymer properties and particle size in stability of co-continuous blend composites
Authors: Shah Rajas Sudhir , Bryant Steven , Trifkovic Milana
Published: May 2023

Interfacially localizing particles in co-continuous polymer blends requires a complex interplay between the properties of polymers, such as interfacial tension between them, Γ, viscosity, η, viscosity ratio between them, and particle properties, such as particle size and particle surface chemistry. Here, we investigate the formation and coarsening dynamics of four co-continuous blend composites based on polypropylene, PP (or linear low-density polyethylene), and poly(ethylene-co-vinyl acetate), EVA filled with pristine silica of two sizes (140 and 250 nm). By choosing polymer blend components with different viscosities and interfacial tensions and particles with varying size and size distributions, we were able to elucidate their relative contributions in the stabilization of co-continuous polymer microstructures. By utilizing confocal rheology, we show that the evolution of storage modulus during coarsening of polymer blend composites is primarily dependent on the strength of the initial interfacial particle network. Our findings indicate that the initial domain size and kinetic control of interfacial particle localization in co-continuous polymer blends are determined by the Γ/η ratio of the neat blend. However, this relationship does not hold in low viscosity systems. When polymer blend viscosity is lower, it reduces the kinetic barrier at the interface, leading to a higher proportion of particles localizing in the favorable EVA phase. We also find that the smaller particles have a higher propensity for interfacial localization. These findings provide insight into the success of kinetic particle trapping at the interface of co-continuous blends and the resulting composite properties based on the choice of component properties.
Non-negative matrix factorization for overlapping community detection in directed weighted networks with sparse constraints
Authors: Wang Wenxuan , Meng Jun , Li Huijia , Fan Jingfang
Published: May 2023

Detecting overlapping communities is essential for analyzing the structure and function of complex networks. However, most existing approaches only consider network topology and overlook the benefits of attribute information. In this paper, we propose a novel attribute-information non-negative matrix factorization approach that integrates sparse constraints and optimizes an objective function for detecting communities in directed weighted networks. Our algorithm updates the basic non-negative matrix adaptively, incorporating both network topology and attribute information. We also add a sparsity constraint term of graph regularization to maintain the intrinsic geometric structure between nodes. Importantly, we provide strict proof of convergence for the multiplication update rule used in our algorithm. We apply our proposed algorithm to various artificial and real-world networks and show that it is more effective for detecting overlapping communities. Furthermore, our study uncovers the intricate iterative process of system evolution toward convergence and investigates the impact of various variables on network detection. These findings provide insights into building more robust and operable complex systems.
A bi-level framework for interactive competition and CPPs-based demand response
Authors: Zhang Sirui , Zhang Jing , Cheng Ling , Wang Zhanbo , Li Wen , Liu Chang
Published: May 2023

This paper proposes a multi-leader–follower framework for interactive competition among participants. To do so, a Stackelberg game model is formulated to take into account the price competition between leaders and captive power plants (CPPs). The retailer and the distribution company (DISCO) adopt a rival strategy to determine sale prices, aiming to maximize respective profit in a competitive market. DISCO pricing bound is set during the interaction process. The response at the lower level also affects hierarchical prices and CPP revenue. CPPs enact demand response viable through load shifting and peer-to-peer (P2P) energy trading. A quadratic penalty function is employed in the model to reduce the peak load demand and reshape the load profile, which brings the load consumption curve close to the forecast value. A general Nash bargaining game is utilized to incentivize P2P energy sharing with neighbors. To solve the multi-leader–follower model, a fixed-point iteration algorithm is proposed, which enables the model to reach convergence. Simulations are conducted to demonstrate the price–demand relationship and hierarchical interaction.
Iron-based superconductors: Teenage, complex, challenging
Authors: Si Qimiao , Hussey Nigel E.
Published: May 2023

Fifteen years after the surprising discovery of superconductivity in iron-based materials, researchers are beginning to impart some of their newfound wisdom on a slew of emerging superconductors that display similar traits.
Physics Today turns 75
Authors: Fitzgerald Richard J.
Published: May 2023

Even as the physical sciences have advanced and transformed, many of the community’s needs and concerns have persisted.
Facile one-step synthesis of gold nanoparticles using Viscum album and evaluation of their antibacterial potential
Authors: Ishaq Muhammad , Numan Muhammad , Zeb Umar , Cui Fengjie , Shad Salma , Hayat Syed Adil , Azizullah Azizullah , Uddin Imad , Iqbal Muzaffar , Rahim Fazli , Khan Naeem , Attia Kotb A. , Fiaz Sajid
Published: May 2023

Nanostructure gold nanoparticles (Au NPs) are well-known biological active materials, synthesised under different environment-friendly approaches that has gained significant interest in the field of biomedicine. This study investigated a novel, fast, easy, cost-effective and the eco-friendly method to synthesise Au NPs from mediated Viscum album Linn plant extract, where the plant metabolites act as stabilising and reducing agents. The synthesised Au NPs were analysed by UV/Vis spectroscopy that gave strong signals and a sharp absorption peak at 545 nm due to the presence of surface plasmon resonance (SPR) bands. In addition, energy dispersive X-ray spectroscopy (EDX) showed that strong signals of Au NPs appeared at 9.7 and 2.3 keV, as the rays of light passed. X-ray diffraction recognised the crystalline material and provided information on the cell unit that the synthesised Au NPs are face-centreed cubic in structure. The diffraction of X-ray spectra showed intense peaks at 38.44°, 44.7°, 44.9° and 77.8°. The mediated V. album plant extracts and synthesised Au NPs were screened against gram-positive and gram-negative (Enterobacter, Salmonella typhi, Escheria coli and Bacillus subtilis) bacterial strains, confirming their antibacterial potential. Au NPs showed strong antibacterial activity due to its unique steric configuration. Au NPs damaged bacterial cell membrane leading to the leakage of the cytoplasm and death of the cell.
A meta-analysis of plant tissue O2 dynamics
Authors: Herzog Max , Pellegrini Elisa , Pedersen Ole
Published: May 2023

Adequate tissue O2 supply is crucial for plant function. We aimed to identify the environmental conditions and plant characteristics that affect plant tissue O2 status. We extracted data and performed meta-analysis on >1500 published tissue O2 measurements from 112 species. Tissue O2 status ranged from anoxic conditions in roots to >53 kPa in submerged, photosynthesising shoots. Using information-theoretic model selection, we identified ‘submergence’, ‘light’, ‘tissue type’ as well as ‘light × submergence’ interaction as significant drivers of tissue O2 status. Median O2 status were especially low (<50% of atmospheric equilibrium) in belowground rhizomes, potato (Solanum tuberosum) tubers and root nodules. Mean shoot and root O2 were ~25% higher in light than in dark when shoots had atmospheric contact. However, light showed a significant interaction with submergence on plant O2, with a submergence-induced 44% increase in light, compared with a 42% decline in dark, relative to plants with atmospheric contact. During submergence, ambient water column O2 and shoot tissue O2 correlated stronger in darkness than in light conditions. Although use of miniaturised Clark-type O2 electrodes has enhanced understanding of plant O2 dynamics, application of non-invasive methods in plants is still lacking behind its widespread use in mammalian tissues.
Ideología en el paisaje lingüístico y semiótico
Authors: Fernández Juncal Carmen
Published: May 2023

Abstracta

El presente estudio rastrea el impacto en el paisaje lingüístico de las elecciones autonómicas vascas del año 2020. A partir de un trabajo de campo en dos localidades de distinto perfil demográfico y político y de encuestas entre los partidos en liza, analizamos, por una parte, la presencia o ausencia en el espacio público de las distintas formaciones y sus estrategias de comunicación. Por otra parte, examinamos los recursos de tipo semiótico empleados en la campaña y la distribución de las dos lenguas de uso en la comunidad en las señales del corpus. Los resultados nos permiten detectar el traslado de los recursos físicos tradicionales al ámbito virtual, esfera que asimila cada vez con más fuerza la funcionalidad de los primeros. Asimismo, se revelan tendencias y tensiones en la elección de lenguas, de acuerdo con la posición en el espectro ideológico, que nos obligan a repensar el propio concepto de autoría en este tipo de investigaciones.
El uso de fuentes documentales y su impacto en la creatividad del estudiante de traducción e interpretación
Authors: Rojo López Ana María , Meseguer Cutillas Purificación , Arqués Abellán Paula
Published: May 2023

Abstracta

El presente artículo pretende explorar el impacto que la documentación y la inteligencia creativa tienen a la hora de resolver retos creativos literarios. Para ello se diseñó un estudio experimental con estudiantes de traducción e interpretación en el que, divididos en dos grupos, debían traducir tres fragmentos que contenían retos creativos. Uno de los grupos tenía acceso a recursos de documentación; el otro, no. Nuestra hipótesis de partida predecía que el uso de herramientas de documentación daría lugar a soluciones menos creativas, pero más precisas, así como que las puntuaciones de los participantes en la prueba de creatividad se correlacionarían con las puntuaciones asignadas a la creatividad de sus soluciones. Los resultados del estudio mostraron que las puntuaciones asignadas a la creatividad de las soluciones eran más altas en el grupo sin acceso a la documentación. Sin embargo, en cuanto a la precisión de las soluciones, nuestra hipótesis solo se corroboró para el parámetro de corrección.
Constructional complexity as a predictor of Korean EFL learners’ writing proficiency
Authors: Kim Hyunwoo , Shin Gyu-Ho , Sung Min-Chang
Published: May 2023

Based on usage-based constructionist approaches to language development, this study investigates the validity of constructional complexity as a predictor of writing proficiency of Korean EFL learners. We analyzed argumentative essays produced by Korean EFL learners and compared a prediction model that uses English argument structure constructions with a conventional T-unit-based model. We first tested the predictive power of a discriminant function model with argument structure constructions as predictors for assessing writing proficiency of lower- and higher-level learners. We then compared the construction-based model to another model that included T-unit measures as predictors. The results validated the contribution of argument structure constructions for predicting L2 writing proficiency: The construction-based model yielded higher prediction accuracy than the T-unit-based model did, confirming that constructional complexity is closely aligned with writing proficiency. These findings demonstrate the significance of a construction-based model as a reliable tool for diagnosing EFL learners’ writing proficiency.
How production and distribution processes shape translations in organisations
Authors: Haapaniemi Riku
Published: May 2023

The Finnish Tax Administration’s OmaVero (OV) e-service is an example of an organisational software development and text production process in which translation plays a significant role. In this article, the concept of materiality is utilised to analyse how aspects of the wider process affect the form and content of OV translations. A distinction is made between the translations’ production and distribution process, the effects of the former being manifested mainly through the use of digital translation tools and those of the latter through the conventions of OV software development. A material analysis reveals a conflict in how these two processes treat language as a textual element: the production process downplays and obscures the connection between language content and its textual environment, while the distribution process attaches great importance to this relationship. This demonstrates how a material perspective can introduce useful nuance into analyses of textual communication processes in translation studies.
Centralspindlin proteins Pavarotti and Tumbleweed along with WASH regulate nuclear envelope budding
Authors: Davidson Kerri A. , Nakamura Mitsutoshi , Verboon Jeffrey M. , Parkhurst Susan M.
Published: May 2023

Nuclear envelope (NE) budding is a nuclear pore–independent nuclear export pathway, analogous to the egress of herpesviruses, and required for protein quality control, synapse development, and mitochondrial integrity. The physical formation of NE buds is dependent on the Wiskott–Aldrich Syndrome protein, Wash, its regulatory complex (SHRC), and Arp2/3, and requires Wash’s actin nucleation activity. However, the machinery governing cargo recruitment and organization within the NE bud remains unknown. Here, we identify Pavarotti (Pav) and Tumbleweed (Tum) as new molecular components of NE budding. Pav and Tum interact directly with Wash and define a second nuclear Wash-containing complex required for NE budding. Interestingly, we find that the actin-bundling activity of Pav is required, suggesting a structural role in the physical and/or organizational aspects of NE buds. Thus, Pav and Tum are providing exciting new entry points into the physical machineries of this alternative nuclear export pathway for large cargos during cell differentiation and development.
Diet-mediated constitutive induction of novel IL-4+ ILC2 cells maintains intestinal homeostasis in mice
Authors: Cui Wanlin , Nagano Yuji , Morita Satoru , Tanoue Takeshi , Yamane Hidehiro , Ishikawa Keiko , Sato Toshiro , Kubo Masato , Hori Shohei , Taniguchi Tadatsugu , Hatakeyama Masanori , Atarashi Koji , Honda Kenya
Published: May 2023

Group 2 innate lymphoid cells (ILC2s) expressing IL-5 and IL-13 are localized at various mucosal tissues and play critical roles in the induction of type 2 inflammation, response to helminth infection, and tissue repair. Here, we reveal a unique ILC2 subset in the mouse intestine that constitutively expresses IL-4 together with GATA3, ST2, KLRG1, IL-17RB, and IL-5. In this subset, IL-4 expression is regulated by mechanisms similar to but distinct from those observed in T cells and is partly affected by IL-25 signaling. Although the absence of the microbiota had marginal effects, feeding mice with a vitamin B1-deficient diet compromised the number of intestinal IL-4+ ILC2s. The decrease in the number of IL-4+ ILC2s caused by the vitamin B1 deficiency was accompanied by a reduction in IL-25–producing tuft cells. Our findings reveal that dietary vitamin B1 plays a critical role in maintaining interaction between tuft cells and IL-4+ ILC2s, a previously uncharacterized immune cell population that may contribute to maintaining intestinal homeostasis.
Full two-dimensional ambipolar CFET-like architecture for switchable logic circuits
Authors: Hu Wennan , Liu Yunlin , Huang Zhangcheng , Dong Jianguo , Wang Yue , Chen Weiao , Sheng Zhe , Sun Haoran , Hu Guangxi , Cong Chunxiao , Zhang David Wei , Lu Ye , Zhou Peng , Zhang Zengxing
Published: May 2023

As the scaling of integrated circuits based on silicon semiconductors becomes increasingly challenging due to the minimum feature size being close to the physical limit, the urgent demand for alternative strategies has fuelled the rapid growth of techniques and material innovations. Here, we report on the fabrication of vertically stacked ambipolar complementary field-effect transistor that is fully composed of two-dimensional materials of WSe2/h-BN/graphene/h-BN/WSe2 heterostructures. The ambipolar feature of the top and bottom WSe2 FET enables a switchable inverter behavior with a favorable voltage gain of up to 75, which can work in both the first and third quadrants. Based on the switchable characteristics, a large voltage swing circuit for single photon avalanche detectors is proposed without any bulky negative-voltage components. This work could open a new pathway for future two-dimensional electronics and ultimate monolithic 3D high-density integration circuits.
Ion expansion dynamics of laser induced multi-elemental plasmas
Authors: Yao Xiang , Schneider Christof W , Bulgakova Nadezhda M , Bulgakov Alexander V , Lippert Thomas
Published: May 2023

Ablation of multi-elemental materials by nanosecond lasers is often used to deposit oxide thin films. Understanding the ablation plume dynamics is of utmost importance to gain a detailed insight into thin film growth of materials with a complex composition. In this study, the plume expansion dynamics of several compound materials (AuCu, La0.33Ca0.67MnO3, and LiMn2O4) were characterized by measuring the angular-dependent kinetic energy (KE) distributions of ionic plasma species produced by KrF- and XeCl-excimer laser ablation in vacuum. The distributions of the lightest plume ions were found to differ fundamentally from those of other ions. The latter are similar to the energy distributions observed in single-component plumes and represent a low-energy peak and high-energy tail, while those for the lightest ions consist of at least two distinct peaks. These observations can be explained by assuming the formation of a dynamic double layer (DL) at the front of the plasma giving rise to different acceleration rates for light and heavier ions. As a consequence, heavier elements stay longer within the dynamic DL and gain larger KEs that leads to the observed ion separation. Extending these considerations into three dimensions yields an anisotropic acceleration concept for the plasma ions with high acceleration rates and longer presence within the DL normal to the target surface and lower acceleration rates and shorter time in the parallel direction.
α-decay half-life of 212Po at stellar temperatures
Authors: Mohr Peter
Published: May 2023

The decay properties of atomic nuclei may be modified in stellar environments. The present study analyzes the α-decay of 212Po at temperatures of several Giga–Kelvin, typical for explosive stellar environments. Contrary to a recent study which claimed a reduction of the half-life of 212Po by up to five orders of magnitude, the present study shows only a moderate reduction of the half-life of less than one order of magnitude up to 2 GK.
Investigating the role of electric fields on flow harmonics in heavy-ion collisions
Authors: Panda Ankit Kumar , Gangadharan Reghukrishnan , Roy Victor
Published: May 2023

Using the blast-wave model, we explore the effect of electric fields on spectra and flow harmonics (especially the elliptic flow) for charged pions and protons. We incorporate the first-order correction to the single-particle distribution function due to the electric fields and the dissipative effect while calculating the invariant yields of hadrons in the Cooper–Frye prescription at the freezeout hypersurface. We find a noticeable correction to the directed and elliptic flow of pions and protons for unidirectional and azimuthal asymmetric electric fields of a magnitude

∼

m

π

2

in the transverse plane. Further, we observe mass dependency of the directed flow generated due to the electric fields. The splitting of particle and antiparticle’s elliptic flow due to the electric fields is also discussed.
Investigation of the inverse magnetocaloric effect with the fraction method
Authors: Yuce S , Kavak E , Yildirim O , Bruno N M , Emre B
Published: May 2023

In this study, we examine Ni49Nb1Mn36In14 (nom. at.%) magnetic shape memory alloy (MSMA) to illustrate the inverse magnetocaloric effect (MCE) using the fraction method. The magnetic entropy change,

Δ

S

mag

, was calculated with both, the fraction method and the thermomagnetic Maxwell relation. Our results demonstrate that there exists a large magnetization difference between field-cooling and field-heating histories in Ni49Nb1Mn36In14 (nom. at.%) MSMA, which can be attributed to the pinning of lattice entropy and magnetic entropy, as it is well-known that the temperature and applied magnetic fields have an opposing effect on the total entropy change. In addition, we describe the inverse MCE and the contradictory roles on the total entropy change between the two stimuli via the fraction method.
Changes induced in the human respiratory tract by chronic cigarette smoking can reduce the dose to the lungs from exposure to radon progeny
Authors: Honorio da Silva E , Davesne E , Bonchuk Y , Ratia G , Madas B , Berkovskyy V , Broggio D
Published: May 2023

Chronic cigarette smoking leads to changes in the respiratory tract that might affect the dose received from exposure to radon progeny. In this study, changes induced by cigarette smoking in the respiratory tract were collected from the literature and used for calculation of the dose received by the lungs and organs outside the respiratory tract. Morphological and physiological parameters affected by chronic smoking were implemented in the human respiratory tract model (HRTM) used by the International Commission of Radiological Protection (ICRP). Smokers were found to receive lung doses 3% smaller than the ICRP reference worker (non-smoking reference adult male) in mines and 14% smaller in indoor workplaces and tourist caves. A similar dose reduction was found for the extrathoracic region of the HRTM. Conversely, kidneys, brain, and bone marrow of smokers were found to receive from 2.3- up to 3-fold of the dose received by the respective organ in the ICRP reference worker, although they remained at least two orders of magnitude smaller than the lung dose. These results indicate that the differences in the lung dose from radon progeny exposure in cigarette smokers and non-smokers are smaller than 15%.
Automation of Kerr microscopy system for domain wall velocity measurements
Authors: Raj Rakhul , Hussain Zainab , Kumar Dileep , Raghavendra Reddy V
Published: May 2023

The present work reports the automation of a Kerr microscopy system for capturing magnetic domains and subsequently measuring the displacement of domain walls (DWs) with pulsed magnetic fields. Suitable algorithms are utilized for enhancing the image contrast, image filtering and the simultaneous quantitative evaluation of images, while the data acquisition with pulsed fields is run in the front-end. In order to test these aspects, DW velocity measurements in the widely studied Pt/Co/Pt system, which exhibits perpendicular magnetic anisotropy, are carried out at different temperatures (

⩽

300 K). It is observed that the obtained features agree with the results reported in the literature, indicating the validity of the developed automation.
Algorithm analysis of defect depth for PVC plate with flat-bottomed holes in active pulsed infrared thermography
Authors: Gou Yi , Li Qingying , Yao Rao , Chen Jianing , Bai Tian
Published: May 2023

Active infrared thermography (IRT) has been extensively employed in non-destructive testing in a wide variety of fields. It is capable of extracting defect information of tested object based on the infrared thermal image sequence. However, conventional infrared thermal images are often subjected to defect information with low pixel resolution, and defects are difficult to quantitatively analyze. By exploiting flat-bottomed holes in a PVC plate as defect specimens, a method for quantitative defect depth recognition based on the fusion principal component analysis (PCA) algorithm with sliding-window mechanism and the one dimensional—residual neural network—convolutional block attention module (1DResnet50_CBAM) model was proposed for the reconstructed image sequence of active IRT to address the above-described issues in this study. First, defect information and location were extracted from the original infrared sequence thermal image of the specimen using PCA algorithm with sliding-window mechanism. Then, the dimension of the defect data was reduced using the temporal characteristic of the infrared temperature field. That is, the three-dimensional defect data were transformed into 1D temporal infrared thermal signal. Moreover, the 1D infrared signal time series corresponding to the defect pixel points in the infrared sequence image served as the input to the network, and the defect depth served as the output for automatic defect detection and depth quantification. As indicated by the results, the proposed method based on the fusion PCA algorithm with sliding-window mechanism and 1DResnet50_CBAM model is capable of accurately detecting and quantifying defects. Compared with conventional prediction algorithms, the proposed model can more effectively extract defect information from the infrared detection images, with the defect depth relative prediction error less than 1.5%. Thus, the proposed model was confirmed as an effective method and model for defect recognition and quantitative analysis using infrared thermal detection technology.
Spatio-temporal graph convolutional networks driven by data-physical fusion for parameter prediction of natural gas dehydration system
Authors: Yin Aijun , Wang Yuanyuan , He Yanlin
Published: May 2023

Triethylene glycol dehydration unit is a piece of essential device for removing moisture from raw natural gas during natural gas production. However, the existing station equipment management systems are mostly collection-oriented with little analysis, lack the effective methods of parameter prediction and fault warning, and the strong coupling between the monitoring parameters is a problem should be study. To solve these problems, this paper analyzes the time dependence and spatial correlation of these parameters. Also, a spatio-temporal graph convolutional networks prediction model driven by data-physical fusion (SG-STGCN) is proposed for constructing the graph structure. Firstly, the signed directed graph model is established based on the physical process, and the weight of each edge is obtained by using the grey relational analysis (GRA). Secondly, by stacking spatio-temporal convolutional modules, the temporal and spatial dependencies over a long range of time are captured to realize multivariate parameter prediction. Then, the real-time monitoring data of a dehydration station are used for analysis. The experimental results showed that the proposed method can achieves the best predict result compared with other methods, and can be used in the fault early warning to maintain high reliability of equipment. Finally, the SG-STGCN has been integrated and tested successfully on the real-time monitoring platform of a dehydration unit.
Tuning the morphology of Cu–MOFs nanostructures for sensitive ascorbic acid sensing
Authors: Wang Zhuo , Li Shanyu , Hu Yurun , Wang Huihu , Xiang Xing , Wei Chenhuinan
Published: May 2023

Metal organic frameworks are an attractive platform to develop fascinating electrocatalysts for the oxidation of ascorbic acid (AA), and their different morphologies have been hinted in literature to impact their sensing performance. In this work, by varying the reaction medium of metal source and organic ligand, copper 2-hydroxybenzene-1,4-dicarboxylate (CuBDC-OH) nanosheets (NSs), nanorods (NRs) and bulk were generated. Thereinto, CuBDC-OH-NSs displayed the highest sensitivity of 151.99 μA mM−1 cm−2 in the linear range of 12–1074 μM, which is 1.5 times greater than that of CuBDC-OH NRs and 3.5 times greater than that of CuBDC-OH bulk. The electrochemical analyzes manifested that the superiority of nanosheets originated from higher oxidative current, larger electrochemical active surface area and lower charge transfer resistance, which enabling the efficient electro-oxidation of AA. Additionally, satisfactory selectivity, stability and reproducibility were obtained.
How do engineers do that?—An interactive introduction to the engineering design process for secondary age school pupils
Authors: McNair Sophie A M , Hayward Samantha J
Published: May 2023

It is widely accepted that the United Kingdom (UK) needs more engineers and professionals with skills in science, technology, engineering and maths (STEM) to benefit the economy and keep up with technological change and innovation. However, the true nature of engineering and STEM careers is often misunderstood, with secondary school pupils unable to identify where engineering benefits their everyday lives. This suggests that the societal impacts of engineering are not well-defined within secondary education, causing a lack of diversity in pupils pursuing STEM careers. The authors have developed an activity that demonstrates the true problem-solving nature of engineering, and the numerous ways in which these skills can be applied to everyday life. While most practical ‘design, build and test’ (DBT) exercises aim to foster student engagement with STEM, this activity also emphasises how the engineering design process is a crucial tool for reaching an optimum solution. Pupils work in teams generating ideas and learning from failure, gaining a greater appreciation of how engineers work and the truly exciting nature of engineering. They achieve this by using the engineering design process to help them complete a DBT activity involving building a bridge from limited materials and testing how much weight it can hold. To ensure all pupils have the same opportunities for engagement, the method of delivery, activity design, key learning outcomes, discussion points, and activity relevance have been carefully considered for pupils across a range of age groups, backgrounds, and subject interests. This makes the designed activity ideal for integration into various subject lessons in secondary school classrooms to expose pupils to engineering. The authors have successfully delivered this activity during numerous outreach schemes for pupils visiting the University of Bath, especially noting pupils’ engagement and enthusiasm.
Thermodynamic quasi-equilibria in high power magnetron discharges: a generalized Poisson–Boltzmann relation
Authors: Köhn Kevin , Krüger Dennis , Eremin Denis , Xu Liang , Brinkmann Ralf Peter
Published: May 2023

The Poisson–Boltzmann (PB) equation is a nonlinear partial differential equation that describes the equilibria of conducting fluids. Using a thermodynamic variational principle based on the balances of particle number, entropy, and electromagnetic enthalpy, it can also be justified for a wide class of unmagnetized technological plasmas (Köhn et al 2021 Plasma Sources Sci. Technol.
30 105014). This study extends the variational principle and the resulting PB equation to high power magnetron discharges as used in planar high power pulsed magnetron sputtering. The example in focus is that of a circular high power magnetron. The discharge chamber

and the magnetic field are assumed to be axisymmetric. The plasma dynamics need not share the symmetry. The domain

is split into the ionization region

close to the cathode where electrons are confined, i.e. can escape from their magnetic field lines only by slow processes such as drift and diffusion, and the outer region
, where the electrons are largely free and the plasma is cold. With regard to the dynamics of the electrons and the electric field, a distinction is made between a fast thermodynamic and a slow dissipative temporal regime. The variational principle established for the thermodynamic regime is similar to its counterpart for unmagnetized plasmas but takes magnetic confinement explicitly into account by treating the infinitesimal flux tubes of

as individual thermodynamic units. The obtained solutions satisfy a generalized PB relation and represent thermodynamic equilibria in the fast regime. However, in the slow regime, they must be interpreted as dissipative structures. The theoretical characterization of the dynamics is corroborated by experimental results on high power magnetrons published in the literature. These results are briefly discussed to provide additional support.
Experimental characterization of TIAGO torch discharges: surface wave discharge behavior and (post-)discharge kinetics
Authors: Morales-Calero F J , Rincón R , Muñoz J , Calzada M D
Published: May 2023

The Torche à Injection Axial sur Guide d’Ondes source—better-known as the TIAGO torch—is a particular type of microwave-induced plasma that has become a focus of technological and scientific interest due to its outstanding features. Moreover, the TIAGO torch device arouses interest thanks to its remarkable performance in many challenging areas, such as green energy generation and graphene production by hydrocarbon decomposition. Although it has not been experimentally demonstrated to date, discharges generated by a TIAGO torch have been theoretically predicted to be surface wave discharges (SWDs), a kind of plasma leading the development of new materials. Therefore, deeper and fundamental research on this device is needed to optimize the implementation of plasma technology in these fields. In this study, the axial distribution of gas temperature, electron density and intensity of the main atomic and molecular emissions have been studied by optical emission spectroscopy when feeding the discharge with different input power values (200, 400 and 600 W). A complete axial characterization of both the dart and the plume regions is depicted and, according to the data obtained for the main plasma parameters, different regions can be identified, with the radiation zone being reported for the first time at atmospheric pressure. The kinetics of both the dart and the plume are discussed and an experimental verification of TIAGO torch behavior as a SWD is presented for the first time.
Band alignment of TiO2/SiC and TiO2/Si heterojunction interface grown by atomic layer deposition
Authors: Zeng Yu-Xuan , Wang Xi-Rui , Zhang Jie , Huang Wei , Yang Lei , Ma Hong-Ping , Zhang Qing-Chun
Published: May 2023

Silicon carbide (SiC) is regarded as a promising semiconductor owing to its wide band gap and high thermal conductivity. Meanwhile, it possesses issues such as interface properties, which may affect the performance of SiC substrate power devices (e.g. MOSFET), especially when compared with similarly structured silicon appliances. Given that the development of SiC semiconductor devices has a number of commonalities with conventional silicon-based semiconductors, titanium dioxide (TiO2), a material that has a great track record in Si-based semiconductor devices, has been chosen for investigation in this work. Although TiO2 is not capable of being a gate dielectric alone on the SiC substrate because of its relatively narrow band gap, it can be adopted into composite or multilayer gate dielectrics to reach satisfying characteristics. As such, the interfacial state and heterostructure between TiO2 and SiC remain worthy being researched. In the present study, the properties of atomic layer deposited (ALD) TiO2 films on silicon substrates were compared with those on 4H-SiC substrates via x-ray photoelectron spectroscopy, atomic force microscopy, and x-ray reflectometry. It is shown that the interface state between ALD TiO2 film and both types of substrates as-deposited have similar chemical conditions, whereby TiO2 layer barely react with substrates, containing great amount of oxygen vacancies. According to band alignment calculations, heterostructure of both samples are type-II heterojunctions with negatively shifted conduction band. Although the large bandwidth of 4H-SiC hinders the use of TiO2 as a gate dielectric in power devices, this structure has the potential for other semiconductor products.
Impact load identification and localization method on thin-walled cylinders using machine learning
Authors: Guo Chenyu , Jiang Liangliang , Yang Fan , Yang Zhiguang , Zhang Xi
Published: May 2023

In this paper, a novel impact load identification and localization method on actual engineering structures using machine learning is proposed. Three machine learning models, including a gradient boosting decision tree (GBDT) model based on ensemble learning, a convolutional neural network (CNN) model and a bidirectional long short-term memory (BLSTM) model based on deep learning, are trained to directly identify and locate impact loads according to dynamic response. The GBDT model and the CNN model can reversely identify force peak and location of impact loads. The BLSTM model can reconstruct the time history of impact loads. The method is verified on a thin-walled cylinder with obvious nonlinearity. The result shows that the method can accurately identify impact loads and its location. The characteristics of the three models are compared and the influence of structural boundary conditions on the accuracy of identification is discussed. The proposed method has the potential to be applied to various engineering structures and multiple load types.
Efficient pathway to NaCs ground state molecules
Authors: Warner Claire , Bigagli Niccolò , Lam Aden Z , Yuan Weijun , Zhang Siwei , Stevenson Ian , Will Sebastian
Published: May 2023

We present a study of two-photon pathways for the transfer of NaCs molecules to their rovibrational ground state. Starting from NaCs Feshbach molecules, we perform bound-bound excited state spectroscopy in the wavelength range from 900 nm to 940 nm, covering more than 30 vibrational states of the

c
3

Σ
+

,

b
3

Π

, and

B
1

Π

electronic states. Analyzing the rotational substructure, we identify the highly mixed

c
3

Σ
1
+

 
|
v
=
22
⟩
∼

b
3

Π
1

 
|
v
=
54
⟩

state as an efficient bridge for stimulated Raman adiabatic passage. We demonstrate transfer into the NaCs ground state with an efficiency of up to 88(4)%. Highly efficient transfer is critical for the realization of many-body quantum phases of strongly dipolar NaCs molecules and high fidelity detection of single molecules, for example, in spin physics experiments in optical lattices and quantum information experiments in optical tweezer arrays.