bluuebunny/crossref_metadata_2025 huggingface dataset:
The positive correlation between the dispersion and catalytic performance of Fe2O3 nanoparticles in nano-Fe2O3–ultrafine AP energetic composites supported by solid UV-vis spectroscopy
Authors: Kou Yong , Luo Peng , Xiao Lei , Xin Yanping , Zhang Guangpu , Hu Yubing , Gao Hongxu , Zhao Fengqi , Jiang Wei , Hao Gazi
Published: August 2023

A method for quantitatively analyzing the dispersion of nanomaterials was developed. The intrinsic relationship between the catalytic properties and the dispersion of the nanomaterials was explored, and a good linear relationship was found.
Selenium microparticles decorated graphene oxideviagreen synthesis usingPsidium guajavaleaves: preparation, characterization, and biological activities
Authors: Tuyen Nguyen Ngoc Kim , Thi Thanh Huong Quach , Duy Bui Thanh , Nam Nguyen Thanh Hoai , Hai Nguyen Duy , An Hoang , Thi Tinh Ninh , Khanh Tran Nhat , Le Hoai Nhi Tran , Ngan Lam Thanh , Hieu Nguyen Huu
Published: August 2023

An environmentally friendly method was used to synthesize selenium microparticles (SeMPs) by applyingPsidium guajavaleaf extracts as a reducing agent.
Highly selective esterification of bioderived itaconic acid to monobutyl itaconate: kinetic analysis of a reusable 20% (w/w) Rb0.5Cs2.0H0.5PW12O40/MCF catalyst system
Authors: Singh Rohitkumar G. , Yadav Ganapati D.
Published: August 2023

Catalyzing circular economy: Bimetallic dodecatungstophosphoric acid on mesostructured cellular foam (MCF) unleashes sustainable transformation of itaconic acid into monobutyl itaconate (MIB), paving the way for eco-friendly biodegradable polymers.
A safer framework to evaluate characterization technologies of exhaled biologic materials using electrospun nanofibers
Authors: Evans David T. , Nelson Dalton J. , Pask Megan E. , Haselton Frederick R.
Published: August 2023

A method to safely monitor exhaled surrogate biomolecules representing pathogens collected on electrospun nanofiber substrates and detected by PCR.
An explainable machine-learning approach for revealing the complex synthesis path–property relationships of nanomaterials
Authors: Jin Kun , Wang Wentao , Qi Guangpei , Peng Xiaohong , Gao Haonan , Zhu Hongjiang , He Xin , Zou Haixia , Yang Lin , Yuan Junjie , Zhang Liyuan , Chen Hong , Qu Xiangmeng
Published: August 2023

We developed an explainable machine learning approach for revealing the synthesis path-property relationships of nanomaterials and constructed a synthetic phase diagram of the fluorescence quantum yield (QY) of GSH-AuNCs.
pH-Switchable phenylalanine-templated copper nanoclusters: CO2 probing and efficient peroxidase mimicking activity
Authors: Shekhar Shashi , Sarker Raibat , Mahato Paritosh , Agrawal Sameeksha , Mukherjee Saptarshi
Published: August 2023

Inter-cluster conversion through the strategic tuning of external stimuli and thereby modulation of the optical properties of metal nanoclusters (MNCs) is an emerging domain for exploration.
Correction: In situ observation of the on-surface thermal dehydrogenation of n-octane on Pt(111)
Authors: Arribas Daniel , Villalobos-Vilda Víctor , Tosi Ezequiel , Lacovig Paolo , Baraldi Alessandro , Bignardi Luca , Lizzit Silvano , Martínez José Ignacio , de Andres Pedro Luis , Gutiérrez Alejandro , Martín-Gago José Ángel , Merino Pablo
Published: August 2023

Correction for ‘In situ observation of the on-surface thermal dehydrogenation of n-octane on Pt(111)’ by Daniel Arribas et al., Nanoscale, 2023, https://doi.org/10.1039/d3nr02564k.
Soluble and cross-linkable polyimides from a vanillin-derived diamine: preparation, post-polymerization and properties
Authors: Zhang Weixian , Wu Qihua , Shao Wen , Li Fangyu , Chen Hongzhu , Pei Yong , Wang Jiajia
Published: August 2023

Soluble polyimides with –OCFCF2 side groups were successfully prepared from a vanillin-derived aromatic diamine. After crosslinking, fluorinated polyimide networks were obtained with high thermal resistance, transparency and mechanical strength.
Correction: Double cross-linked transparent superhydrophilic coating capable of anti-fogging even after abrasion and boiling
Authors: Liu Xingyu , Xu Lili , Zhao Shuaisheng , Hua Haoxuan , Su Yifan , Yu Xinquan , Wang Jinlei , Li Gang , Zhang Youfa
Published: August 2023

Correction for ‘Double cross-linked transparent superhydrophilic coating capable of anti-fogging even after abrasion and boiling’ by Xingyu Liu et al., RSC Adv., 2023, 13, 23409–23418, https://doi.org/10.1039/D3RA03113F.
Effect of Face Masks and Speech Style on Speech Intelligibility and Listener Effort in Parkinson's Disease
Authors: Cline Nathaniel , Knowles Thea , Badh Gursharan
Published: August 2023

Purpose:

The aim of this study was to quantify the combined effects of face masks and effortful speech styles on listener intelligibility and perceived listener effort in talkers with and without Parkinson's disease (PD).

Method:

Ten people with PD and 10 healthy, older controls read aloud sentences in two face mask and three speech style conditions. Masks included no mask and KN95 masks. Speech styles included habitual, clear, and loud. Listener participants were tasked with listening to each sentence mixed with background noise and then transcribing what they heard and rating how effortful it was to understand. Listener accuracy and effort were each modeled as a function of speaker group, face mask, and speech style using mixed-effects regression models.

Results:

Listeners were less accurate and reported greater listening effort for the PD group and for the mask condition. Listeners were more accurate and reported less effort when listening to clear and loud compared to habitual speech. Listener accuracy and listener effort were strongly negatively correlated across all conditions. Face masks were also associated with a steeper decline in speech intelligibility and an increase in listener effort for talkers with PD.

Discussion:

Face masks resulted in steeper speech intelligibility decline for talkers with PD compared to controls. Speaking more loudly or more clearly when wearing a face mask improved intelligibility for talkers with PD compared to habitual speech, and both speech styles resulted in speech intelligibility levels that approximated talkers' baseline intelligibility levels without a mask.
A novel composite fixed‐time sliding mode control scheme for second‐order systems with mismatched disturbances: application to Buck converter
Authors: Cai Zhongze , Sun Guhao , Zeng Qingshuang
Published: August 2023

In this paper, a composite fixed‐time sliding mode controller is proposed to address the problems of finite‐time escape and large initial error inherent in disturbance observer (DOB) based controllers. The proposed hybrid control strategy utilizes a fixed‐time DOB and is designed to stabilize a class of second‐order systems in the presence of both matched and mismatched disturbances, while ensuring fixed‐time convergence. First, a fixed‐time DOB is developed to estimate both types of disturbances. Second, a robust sliding mode variable with variable exponent coefficient and a former finite‐time sliding mode controller are proposed to guarantee state convergence without using DOB estimation, thereby preventing the state from diverging due to the unknown large initial error caused by DOB and ensuring convergence prior to switching. Third, a latter robust fixed‐time DOB‐based controller is designed after exact estimation of disturbances is achieved and an estimation of the overall convergence time is provided. Furthermore, strict Lyapunov analysis is employed to prove that the disturbed system under the fixed‐time DOB and composite sliding mode controller is fixed‐time stable. Simulation results for a standard planar uncertain system and Buck converter with mismatched disturbance demonstrate the effectiveness of the proposed controller.
An adaptive enhancement method based on stochastic parallel gradient descent of glioma image
Authors: Wang Hongfei , Peng Xinhao , Ma ShiQing , Wang Shuai , Xu Chuan , Yang Ping
Published: August 2023

Brain tumour diagnosis is significant for both physicians and patients, but the low contrast and the artefacts of MRI glioma images always affect the diagnostic accuracy. The existing mainstream image enhancement methods are insufficient in improving contrast and suppressing artefacts simultaneously. To enrich the field of glioma image enhancement, this research proposed a glioma image enhancement method based on histogram modification and total variational using stochastic parallel gradient descent (SPGD) algorithm. Firstly, this method modifies the cumulative distribution function on the image histogram and performs gamma correction on the image according to the modified histogram to obtain a contrast‐enhanced image. Then, the method suppresses the artefacts of glioma images by total variational and wavelet denoising algorithm. To get better enhancement images, the optimal parameters in the proposed method are searched by the SPGD algorithm. The statistical studies performed on 580 real glioma images demonstrate that the authors’ approach can outperform the existing mainstream image enhancement methods. The results show that the proposed method increases the discrete entropy of the image by 8.9% and the contrast by 2.8% compared to original images. The enhanced images are produced by the proposed method with a natural appearance, appealing contrast, less degradation, and reasonable detail preservation.
The heart of Sakurai’s object revealed by ALMA
Authors: Tafoya Daniel , van Hoof Peter A. M. , Toalá Jesús A. , Van de Steene Griet , Randall Suzanna , Unnikrishnan Ramlal , Kimeswenger Stefan , Hajduk Marcin , Barría Daniela , Zijlstra Albert
Published: August 2023

We present high-angular-resolution observations of Sakurai’s object using the Atacama Large Millimeter Array, shedding new light on its morpho-kinematical structure. The millimetre continuum emission observed at an angular resolution of 20 milliarcsec (corresponding to 70 AU) reveals a bright compact central component whose spectral index indicates that it is composed of amorphous carbon dust. Based on these findings, we conclude that this emission traces the previously suggested dust disc observed in mid-infrared observations, and therefore our observations provide the first direct imaging of this disc. The H12CN(J = 4 → 3) line emission observed at an angular resolution of 300 milliarcsec (corresponding to 1000 AU) displays a bipolar structure with a north–south velocity gradient. From the position–velocity diagram of this emission, we identify the presence of an expanding disc and a bipolar molecular outflow. The inclination of the disc is determined to be i = 72°. The derived values for the de-projected expansion velocity and the radius of the disc are vexp = 53 km s−1 and R = 277 AU, respectively. On the other hand, the de-projected expansion velocity of the bipolar outflow detected in the H12CN(J = 4 → 3) emission is of approximately 1000 km s−1. We propose that the molecular outflow has an hourglass morphology with an opening angle of around 60°. Our observations unambiguously show that an equatorial disc and bipolar outflows formed in Sakurai’s object during the 30 years following the occurrence of the born-again event, providing important constraints for future modelling efforts of this phenomenon.
Creation of column-oriented NoSQL databases automatically in Big Data environments and its impact on energy consumption
Authors: Elotmani Fouad , Esbai Redouane , Atounti Mohamed
Published: August 2023

This study investigates the automatic creation of column-oriented NoSQL databases in Big Data environments and their impact on energy consumption. Traditional row-oriented databases face limitations in handling large volumes of data, resulting in slower query response times and energy inefficiencies. In contrast, column-oriented NoSQL databases store data in columns, enabling efficient compression, retrieval, and query processing. Innovative techniques are employed to automatically create these databases, optimizing performance and minimizing manual intervention. Storing data in a columnar format reduces storage requirements and power consumption while improving data locality and reducing I/O operations. This study emphasizes the benefits of adopting column-oriented NoSQL databases, including improved performance, scalability, and energy efficiency in Big Data environments.
Contribution to Electrical System Inertia of Dual Fuel two-stroke Engines in Isolated Grid: A Case Study
Authors: D’Agostino Fabio , Gabriele Bruno , Silvestro Federico , Trasverso Alberto , Sala Silvio
Published: August 2023

The paper analyzed the dynamic performance of dual two-stroke engines with respect to classical Diesel gensets and the contribution to increase the rotating inertia of an isolated electrical grid with significant penetration of Renewable Energy Sources (RESs). The role of genset capable to provide better inertia and primary frequency regulation is essential for the integration of renewable generation in order to provide frequency stability and better power quality.
Ammonia as hydrogen carrier for transport application
Authors: Rivarolo Massimo , Clematis Davide , Bellotti Daria , Barbucci Antonio
Published: August 2023

As the interest in hydrogen to help the decarbonization of the transport sector is growing fast, the interest in new methods for its storage is a key point to improve its diffusion in many contexts, investigating innovative methods. Ammonia is a promising solution, as its hydrogen content per volume unit is higher than hydrogen stored in liquid form; furthermore, ammonia does not require cryogenic temperature nor high amounts of energy for liquefaction. In this study, two different plant layouts have been investigated, considering as a case study an ammonia-to-hydrogen conversion plant to feed a bus station composed of ten hydrogen buses (106 kg H2/day). In the end, a techno-economic analysis is performed to investigate the Levelized Cost of Hydrogen production from ammonia for the two cases and evaluate the most feasible solution. For both the plant layouts, the following results are obtained: (i) the optimal size of the main components; (ii) the global energy efficiency; (iii) the purity of H2 obtained; (iv) the H2 production cost. Finally, the size effect is investigated to evaluate the economic feasibility of the best plant solution for large-scale hydrogen refuelling stations (2000 kg H2/day), which are a more representative case for future implementations.
Dynamics and control implementation of a supercritical CO2 simple recuperated cycle
Authors: Maccarini Simone , Tucker Swatara , Mantelli Luca , Barberis Stefano , Traverso Alberto
Published: August 2023

Interest in supercritical CO2 power cycles is constantly increasing, showing good efficiency, and promising competitive costs and enhanced flexibility with respect to competing systems. Some project within the EU Horizon 2020 program have studied these systems and aim to demonstrate them in large scale, following the example of the STEP project in US. This work is part of the effort of the SOLARSCO2OL project to build a sCO2-CSP power demo plant at MW scale.

A dynamic model of a simple recuperated sCO2 cycle is developed in TRANSEO, using miniREFPROP to compute fluid properties, and table of properties are implemented, when possible, to enhance the performance of the code. Control logics is described and simple controllers implemented. Finally, controllers are tested showing the response of the main parameters of the plant to a ramp variation of the load. Stable compressor inlet pressure is achieved with an inventory control, while a stable turbine inlet temperature allows a high efficiency in part-load operation.
Decentralised Hybridised Energy Management Systems (DHEMS) in power grids
Authors: Baraja David , Riesco Antonio , Alonso Alberto , Skrt Darja , Andolsek Andraz , Gutschi Christoph , Arnanz Roberto , Gallego M. Ángeles
Published: August 2023

The integration of electric batteries along the power supply chain is crucial for the transformation of the energy sector towards a new flexible grid that allows the penetration of renewable power generation while ensuring stability and supply security. Batteries penetration in the grid can be boosted through an efficient management of heterogeneous generation sources, controllable loads and batteries, according to different criteria of stability, efficiency, cost, maintenance and power flow requirements. The Distributed Hybrid Energy Management System (DHEMS) is a management software tool able to solve an optimization problem maximizing renewable energy sources exploitation. The DHEMS has been designed with two control layers. First, the Cloud DHEMS layer accepts external setpoints (from a VPP, DSO or TSO) and dispatchs the total active and reactive power to be exchanged with the grid by a set of distributed plants. Second, the Local DHEMSs are in charge of distributing received set points and commands among the local sets that form each power plant. Different real control and communication tests have been done, in La Plana facility (owned by Siemens Gamesa Renewable Energy).
Analysis and evaluation of Worldwide Carbon emission topics in economic journals: a review on articles published during 2016-2021
Authors: Khalimjonov Nurbek , Allayarov Piratdin , Tajibaeva Kizlargul
Published: August 2023

Carbon dioxide is the most prevalent gas, prompting researchers to investigate carbon reduction and mitigation measures. Carbon emission reporting is just one aspect of this domain’s research, which also includes identifying and implementing carbon mitigation and reduction measures. However, there isn’t a thorough study accessible to track global research on carbon emissions. As a result, this study examined the global literature on carbon emissions using a scientometric analytic method. From 2016 to 2021, 167 bibliographic records were taken from the Scopus collection database and evaluated utilizing author, journal, country, and keyword analysis approaches. China, Turkey, the United States, and the United Kingdom made the most substantial contributions to the domain. The findings revealed that over the study period, the publication of papers relating to carbon emissions increased, and China produced a greater number of publications and authors (45.12 percent of total). Furthermore, this page examines the most commonly used input keywords. The major findings of this study will be useful for politicians, researchers, and institutions in determining future research directions and identifying whom they might consult to assist in formulating carbon emission control policies and future carbon reduction objectives, according to the authors.
Development of mathematical model of the system of small businesses
Authors: Kolosova Olga , Leonova Olesya , Makarenko Elena , Usenko Ludmila , Shchemelev Sergey
Published: August 2023

The purpose of this work is to develop the model and quantitative parameters of the system of small enterprises. The processes of small business development should be identified, formalized and presented in the form of a mathematical model, allowing the use of forecasting and regulation of the system of small enterprises. Mathematical and statistical research of quantitative changes in the small business system under the influence of various external factors. The indicators most adequately reflecting small business development have been established. External factors that have a predominant influence on the development of small businesses are identified. A mathematical model of a small business was developed. The tools of the conducted research can be used in different countries to improve the level of regulation and forecasting of the system of small enterprises. Developed a mathematical model for development of the system of small enterprises.
Evaluation of the use of inter-company platform relations
Authors: Popov E.V. , Simonova V.L. , Yudina O.L.
Published: August 2023

The research objective of this study is to systematize the experience of organizing digital platforms in the field of inter-company relations to assess the level of their use by Russian enterprises. The research is based on a methodological generalization of published scientific results and an empirical analysis of general trends in the development of the organization of inter-firm interaction based on digital platforms among manufacturing enterprises. The obtained results showed the presence of several types of digital platforms used for the organization of inter-company relations. The practice of Russian enterprises is dominated by simpler platform solutions aimed at increasing the transactional efficiency of inter-firm interactions, allowing their participants to achieve positive effects associated with an increase in the number of counterparties, an increase in sales, a reduction in risks and transaction costs of interaction with counterparties. It is concluded that the possibility of achieving more significant transformational effects is associated with the development of technological ecosystems of platforms, which requires the participating enterprises to significantly transform business processes based on costly investments in capital-intensive and technologically complex solutions.
Formation of a portfolio of digital technologies and solutions for the production and storage of agricultural products
Authors: Zolkin A.L. , Matvienko E.V. , Bityutskiy A.S. , Adzhieva A.I.
Published: August 2023

Guaranteeing food security in the country is a multifaceted issue that requires a comprehensive solution. It is important not only to produce raw materials for food products, but also to establish an efficient logistics network that will ensure delivery to the final consumer. In order to do it, it is important to store agricultural products, livestock and fish, as well as to create a reliable material base that will ensure the safety of products throughout the entire storage period.
Non-vitamin K Antagonist Oral Anticoagulant, Warfarin, and ABC Pathway Adherence on Hierarchical Outcomes: Win Ratio Analysis of the COOL-AF Registry
Authors: Treewaree Sukrit , Lip Gregory Y. H. , Krittayaphong Rungroj
Published: August 2023

Background Atrial fibrillation (AF) Better Care (ABC) pathway adherence is associated with improved outcomes. Clinical trials have shown that non-vitamin K antagonist oral anticoagulants (NOACs) are as least as effective as warfarin for stroke prevention in AF patients. The Win Ratio method, analyzing hierarchical composite outcomes considering event timing and severity, has limited data on its use in Asians.

Objectives We aim to apply Win Ratio in a registry to access the comparative effectiveness of NOACs versus warfarin and ABC adherence versus nonadherence in Asian patients with AF.

Methods Our study included nonvalvular AF patients from the nationwide prospective COOL-AF registry in Thailand. The NOAC-treated group was compared with the warfarin-treated group using the Win Ratio, with the following order: all-cause death, intracranial hemorrhage (ICH), ischemic stroke/transient ischemic attack/systemic embolism, non-ICH major bleeding, and myocardial infarction or heart failure. ABC pathway adherence versus nonadherence was also compared. A Win Ratio greater than 1.00 indicating a better outcome.

Results The analysis included 2,568 patients, with 228 in the NOAC group and 2,340 in the warfarin group. The NOAC group had more wins than the warfarin group, with an unmatched Win Ratio of 1.64 (95% confidence interval [CI]: 1.22–2.20; p < 0.001). When compared with nonadherence, ABC pathway adherence was associated with a Win Ratio of 1.57 (95% CI: 1.33–1.85; p < 0.001).

Conclusion This Win Ratio analysis demonstrates the significant benefits of NOACs over warfarin and ABC pathway adherence over nonadherence in reducing the composite outcome in patients with AF.
An improved source of spin-polarized electrons based on spin exchange in optically pumped rubidium vapor
Authors: Ahrendsen K. J. , Trantham K. W. , Tupa D. , Gay T. J.
Published: August 2023

We have improved a polarized electron source in which unpolarized electrons undergo collisions with a mixture of buffer gas molecules and optically spin-polarized Rb atoms. With a nitrogen buffer gas, the source reliably provides spin polarization between 15% and 25% with beam currents >4 μA. Vacuum pump upgrades mitigate problems caused by denatured diffusion pump oil, leading to longer run times. A new differential pumping scheme allows the use of higher buffer gas pressures up to 800 mTorr. With a new optics layout, the Rb polarization is continuously monitored by a probe laser and improved pump laser power provides more constant high polarization. We have implemented an einzel lens to better control the energy of the electrons delivered to the target chamber and to preferentially select electron populations of higher polarization. The source is designed for studies of biologically relevant chiral molecule samples, which can poison photoemission-based GaAs polarized electron sources at very low partial pressures. It operates adjacent to a target chamber that rises to pressures as high as 10−4 Torr and has been implemented in a first experiment with chiral cysteine targets.
Photonic topological insulators induced by non-Hermitian disorders in a coupled-cavity array
Authors: Luo Xi-Wang , Zhang Chuanwei
Published: August 2023

Recent studies of disorder or non-Hermiticity induced topological insulators inject new ingredients for engineering topological matter. Here, we consider the effect of purely non-Hermitian disorders, a combination of these two ingredients, in a 1D coupled-cavity array with disordered gain and loss. Topological photonic states can be induced by increasing gain-loss disorder strength with topological invariants carried by localized states in the complex bulk spectra. The system showcases rich phase diagrams and distinct topological states from Hermitian disorders. The non-Hermitian critical behavior is characterized by the biorthogonal localization length of zero-energy edge modes, which diverges at the critical transition point and establishes the bulk-edge correspondence. Furthermore, we show that the bulk topology may be experimentally accessed by measuring the biorthogonal chiral displacement, which can be extracted from a proper Ramsey interferometer that works in both clean and disordered regions. The proposed coupled-cavity photonic setup relies on techniques that have been experimentally demonstrated and, thus, provides a feasible route toward exploring such non-Hermitian disorder driven topological insulators.
Experimental study on the axial growth characteristics of streamer stem during dark period in long spark discharge
Authors: Cheng Chen , He Hengxin , Huang Yubin , Fu Zhong , Zhao Aihua , Xiang Nianwen , Chen Weijiang
Published: August 2023

This paper presents an original investigation into the axial evolution of streamer stem during a dark period in long spark discharge. To obtain thermodynamic morphology and temperature distribution of stems, we set up a quantitative schlieren system with the temporal and spatial resolutions of 0.37 μs and 31 μm/pixel, respectively. The quantitative schlieren observation experiments of positive leader discharge with a 1.0 m rod-plate gap were carried out, and the time-resolved quantitative schlieren images were captured. Furthermore, the temperature distribution of stems and its morphology evolution in the axial direction during a dark period were obtained. Due to the dispersion of first streamer discharge, the gas temperature in stem roots shows two evolutionary trends, namely, rising and falling. It was found that the gas temperature in stem decreased along the axis with the increase in the distance from stem root, and the gas temperature of a thermal thin channel was between 400 and 800 K. There is a significant dependency between axial development parameters of thermal thin channels and the first streamer discharge parameters. The phenomenon of channel abrupt elongation triggered by secondary streamer discharge was observed by the schlieren system, and the influence of characteristic parameters on the inception of secondary streamer was statistically analyzed. The ion current waveform in leader relaxation phase was measured, and it is clarified that the generation mechanism of thermal thin channels is due to the energy transfer between positive ions and neutral particles, which finally leads to the increase in gas temperature in the channels.
Coherent structures and turbulent model refinement in oblique shock/hypersonic turbulent boundary layer interactions
Authors: Yu Ming , Sun Dong , Zhou QingQing , Liu PengXin , Yuan XianXu
Published: August 2023

In the present study, we investigate the evolution of turbulent statistics and coherent structures in hypersonic turbulent boundary layers at the Mach number of 5 impinged by oblique shock waves generated by the wedge with the angles of 14°, 10°, and 6°, inducing strong, mild, and incipient flow separation, by exploiting direct numerical simulation databases, for the purpose of revealing the underlying flow physics that are of significance to turbulent modeling. We found that the large-scale structures are amplified within the interaction zone, manifested in the form of large-scale low- and high-speed streaks with the spanwise length scale of boundary layer thickness, and gradually decay downstream, the process of which is extremely long. The abrupt variation in the characteristic length, time, and velocity scales as well as the incompatible viscous dissipation of the mean and turbulent kinetic energy results in the incorrect predictions by the Reynolds-Averaged Navier–Stokes (RANS) equation simulations, provided the models are established based on solving the transport equations of the turbulent kinetic equation and its viscous dissipation (k−ε or k−ω models, for instance). To amend this issue, we propose to refine the parameters in the model as the functions of wall pressure, the flow quantities related to multiple flow features. The RANS simulations with the k−ω SST model utilizing the proposed refinement improve greatly the accuracy of the skin friction, wall heat flux, and Reynolds shear stress downstream of the interaction zone, and the wall pressure distributions in hypersonic turbulence over compression ramp, suggesting its promising prospect in engineering applications.
Design of sensitive materials for nitrogen oxides detection
Authors: Zuo Hua-Mei , Xu Wang-Ping , Wu Guang , Wei Xiao-Lin , Zhou Yun , Cao Jue-Xian
Published: August 2023

Although the d-band center theory can well describe the interaction between gas molecules and transition metal surfaces, the detailed reaction process and specific adsorption conditions are unclear. Hence, in this work, we systematically studied the adsorption mechanism, adsorption conditions, and recovery time of NO and NO2 molecules on different transition metals (Cu, Ag, Au, Ni, Pd, Pt, Rh, Ru, Tc, Mo, Nb, and Zr) surfaces by first-principles. The results indicated that the charge transfers from the dz2, dxz, and dyz orbitals of substrate atoms to the HOMOs/LUMOs of NO and NO2. Moreover, we demonstrate that the interaction orbitals between the NO/NO2 and the metal atoms excellently correspond with the match of energy level and parity, and the maximum overlap of the orbital wave function. Interestingly, the excellent linear scaling between charge transfer and the d-band center, work function, and matrix element (V2ad) of metals has been confirmed. Specifically, the different recovery times of these systems at different temperatures were explored. Our results can provide a feasible way for exploring gas-sensitive materials in the experiments.
Enhanced emission collection of VB− in hexagonal boron nitride by solid immersion lens and plasmon
Authors: Yang Yuan-Ze , Liu Wei , Zeng Xiao-Dong , Guo Nai-Jie , Li Zhi-Peng , Xie Lin-Ke , Liu Jun-You , Wang Yi-Tao , Wang Zhao-An , Zhou Ji-Yang , Xu Jin-Shi , Tang Jian-Shun , Li Chuan-Feng , Guo Guang-Can
Published: August 2023

Hexagonal boron nitride (hBN) has brought widespread attention as a host material of various quantum emitters due to its two-dimensional nature and wide bandgap. Among the versatile quantum emitters in hBN, the negatively charged boron vacancy (VB−) stands out for its high contrast of optically detected magnetic resonance signal and the ability of spin control. Here, we report a method to implement 8.6-fold photoluminescence enhancement of VB− by using a solid immersion lens (SIL). We further combined an Au waveguide, Ag nanoparticles, and SIL to achieve an 18.6-fold photoluminescence overall enhancement of VB−. Our work provides a portable method to enhance the collection and emission efficiency of VB−, which is helpful for its practical applications in quantum technologies such as quantum sensing and quantum information.
How exceptional are the classic adaptive radiations of passerine birds?
Authors: Miles Donald B. , Ricklefs Robert E. , Losos Jonathan B.
Published: August 2023

We investigated whether celebrated cases of evolutionary radiations of passerine birds on islands have produced exceptional morphological diversity relative to comparable-aged radiations globally. Based on eight external measurements, we calculated the disparity in size and shape within clades, each of which was classified as being tropical or temperate and as having diversified in a continental or an island/archipelagic setting. We found that the distribution of disparity among all clades does not differ substantively from a normal distribution, which would be consistent with a common underlying process of morphological diversification that is largely independent of latitude and occurrence on islands. Disparity is slightly greater in island clades than in those from continents or clades consisting of island and noninsular taxa, revealing a small, but significant, effect of island occurrence on evolutionary divergence. Nonetheless, the number of highly disparate clades overall is no greater than expected from a normal distribution, calling into question the need to invoke key innovations, ecological opportunity, or other factors as stimuli for adaptive radiations in passerine birds.
Linguistic mechanisms of colour term evolution
Authors: Bochkarev Vladimir V. , Shevlyakova Anna V. , Solovyev Valery D. , Rakhilina Ekaterina V. , Paramei Galina V.
Published: August 2023

We investigated diachrony of distributional semantics of two competing Russian colour terms (CTs) for ‘brown’,
buryj (11th century) and koričnevyj (17th century), using the Russian subcorpus of Google Books Ngram (2020). Time-series analysis (1800–2019) of bigrams gauged each term’s
frequencies of occurrence and changes in combinability with nouns for natural objects, artefacts, abstract concepts and figurative
expressions. In frequency, koričnevyj overtook buryj in the 1920s, confirming its basic status
in modern Russian. The perplexity index indicates that koričnevyj steadily increased the range of denoted
objects, with artefacts being front runners in the buryj-to-koričnevyj transition. The results
corroborate Rakhilina’s (2007a, 2007b, 2008) hypothesis that an incipient CT initially collocates with nouns denoting artefacts
but gradually expands to the realm of natural objects supplanting an old CT. Moreover, koričnevyj and
buryj are discerned by denotations and connotations. The present findings provide insights into general
mechanisms of the linguistic evolution of an emergent basic CT.
CaMKII mediates sexually dimorphic synaptic transmission at neuromuscular junctions in C. elegans
Authors: Zeng Wan-Xin , Liu Haowen , Hao Yue , Qian Kang-Ying , Tian Fu-Min , Li Lei , Yu Bin , Zeng Xian-Ting , Gao Shangbang , Hu Zhitao , Tong Xia-Jing
Published: August 2023

Sexually dimorphic behaviors are ubiquitous throughout the animal kingdom. Although both sex-specific and sex-shared neurons have been functionally implicated in these diverse behaviors, less is known about the roles of sex-shared neurons. Here, we discovered sexually dimorphic cholinergic synaptic transmission in C. elegans occurring at neuromuscular junctions (NMJs), with males exhibiting increased release frequencies, which result in sexually dimorphic locomotion behaviors. Scanning electron microscopy revealed that males have significantly more synaptic vesicles (SVs) at their cholinergic synapses than hermaphrodites. Analysis of previously published transcriptome identified the male-enriched transcripts and focused our attention on UNC-43/CaMKII. We ultimately show that differential accumulation of UNC-43 at cholinergic neurons controls axonal SV abundance and synaptic transmission. Finally, we demonstrate that sex reversal of all neurons in hermaphrodites generates male-like cholinergic transmission and locomotion behaviors. Thus, beyond demonstrating UNC-43/CaMKII as an essential mediator of sex-specific synaptic transmission, our study provides molecular and cellular insights into how sex-shared neurons can generate sexually dimorphic locomotion behaviors.
Filippo Giancotti: Of integrins, signaling, and risotto
Authors: Altieri Dario C.
Published: August 2023

Dario Altieri discusses the life and achievements of Filippo Giancotti, who passed away on July 14, 2023.
Fitting for the energy levels of hydrogen
Authors: Jacobs David M , Horbatsch Marko
Published: August 2023

Atomic hydrogen energy levels calculated to high precision are required to assist experimental researchers working on spectroscopy in the pursuit of testing quantum electrodynamics (QEDs) and probing for physics beyond the Standard Model. There are two important parts to the problem of computing these levels: an accurate evaluation of contributions from QED and using an accurate value for the proton charge radius as an input. Recent progress on QED corrections to the fine structure, as well as increasing evidence that a proton charge radius in the range of 0.84 fm is favored over the previously adopted larger value in the 0.88 fm range, has advanced the field, yet several state-of-the-art measurements remain in contradiction with this smaller value. Motivated by on-going and future work in this area, we present here a simple parameterization for the energy levels of hydrogen at the level of hyperfine structure using the so-called relativistic Ritz approach. The fitting of a finite sample of QED-generated levels at low to intermediate principal quantum number, n, gives a generally applicable formula for all values of n for each distinct angular momentum channel, given in this work up to orbital angular momentum number

ℓ
=
30

. We also provide a simple linear parameterization for the shift in hydrogen energy levels as a function of the proton radius, providing a useful cross check for extant and future measured energy intervals.
Collisions of low- to intermediate-energy electrons with acetonitrile
Authors: da Mata Victor A S , Fujimoto Milton M , Homem Manoel G P
Published: August 2023

A systematic investigation was carried out on the elastic scattering of low- to intermediate-energy electrons (

E
0

= 0.1–1000 eV eV) by acetonitrile (CH3CN). We calculated differential (DCS), integral (ICS), momentum-transfer (MTCS), and total absorption cross sections from 0.1 to 1000 eV energy range using an absorption-effects-implemented ePolyScat-E3 suite of codes, which applies the Schwinger variational method combined with the Padé-approximants technique. Also, the screen-corrected independent atom model was used to compute DCSs, ICSs, and MTCSs from 10–1000 eV impact energies. Present results are compared to other theoretical and experimental data when available. In general, our DCS and MTCS results show a good agreement with available data, however, the ICSs and the resonance features exhibit fair accordance. Our results show two shape-resonance structures: one at about 3.4 eV and a second at about 7 eV. They are labeled as

π
∗

and

σ
∗

, and comprise the

2

E

and

2

A

1

scattering channels, respectively.
Reducing phase transition temperature of vanadium dioxide by ascorbic acid
Authors: Wang Yue , Zhang Yuxin , Xi Xuekui , Yu Zhisong , Lu Di , Lu Yue , Wang Wenhong
Published: August 2023

The phase transition of vanadium dioxide brings huge change in its optical property, which is well used in thermochromic window, fixed-temperature heat sensor, laser protection and other fields. Tunable phase transition temperature is one key for its wide applications. In this paper we verified a new simple method to reduce phase transition temperature. A coordination effect of ascorbic acid on VO2 powder reduces its phase transition temperature to about 32 °C. This simple method offers a new efficient option to deal with VO2, which may dramatically promote the applications of VO2.
Multiple-q current states in a multicomponent superconducting channel
Authors: Yerin Yuriy , Drechsler Stefan-Ludwig , Cuoco Mario , Petrillo Caterina
Published: August 2023

It is well-established that multicomponent superconductors can host different nonstandard phenomena such as broken-time reversal symmetry (BTRS) states, exotic Fulde–Ferrell–Larkin–Ovchinnikov phases, the fractional Josephson effect as well as plenty of topological defects like phase solitons, domain walls and unusual vortex structures. We show that in the case of a two-component superconducting quasi-one-dimensional channel this catalogue can be extended by a novel inhomogeneous current state, which we have termed as a multiple-q state, characterized by the coexistence of two different interpenetrating Cooper pair condensates with different total momenta. Within the Ginzburg–Landau formalism for a dirty two-band superconductor with sizable impurity scattering treated in the Born-approximation we reveal that under certain conditions, the occurrence of multiple-q states can induce a cascade of transitions involving switching between them and the homogeneous BTRS (non-BTRS) states and vice versa leading this way to a complex interplay of homogeneous and inhomogeneous current states. We find that hallmarks of such a multiple-q state within a thin wire or channel can be a saw-like dependence of the depairing current and the existence of two distinct stable branches on it (a bistable current state).
A closed-loop torsional micro-thrust measurement system
Authors: Wang Jiabin , Long Jianfei , Xu Luxiang , Cong Linxiao , Guo Ning , Yang Wei
Published: August 2023

In view of the future space gravitational wave detection mission, a closed-loop monofilament torsional pendulum micro-thrust measurement system has been developed according to the requirements of the drag-free control of the satellite platform for the thrust of the micro-thruster. In this paper, we present the design of the micro-thrust measurement system, the electromagnetic force generation device, and the angular displacement differential measurement. By calibrating the electromagnetic force generation device, the functional relationship between micro-thrust and torsional angular displacement of the torsion scale is obtained, and then the micro-thrust measurement is carried out. The analysis considers the impact of the experimental device’s structure and environment on the micro-thrust measurement system. The range for measuring thrust is 1–246 μN, with a resolution of 0.1 μN and a relative uncertainty of 1.174%. Ensure that the thrust resolution and accuracy of the micro-thruster are met according to the measurement requirements.
Identification of hybrid amyloid strains assembled from amyloid-β and human islet amyloid polypeptide
Authors: Wu Rongrong , Wang Zengkai , Jia Zili , Li Chenglong , Wang Jie , Liu Lei , Dong Mingdong
Published: August 2023

Cross-fibrillation of amyloid-β (Aβ) peptides and human islet amyloid polypeptides (hIAPP) has revealed a close correlation between Alzheimer’s disease and type 2 diabetes (T2D). Importantly, different amyloid strains are likely to lead to the clinical pathological heterogeneity of degenerative diseases due to toxicity. However, given the complicated cross-interactions between different amyloid peptides, it is still challenging to identify the polymorphism of the hybrid amyloid strains and reveal mechanistic insights into aggregation, but highly anticipated due to their significance. In this study, we investigated the cross-fibrillation of Aβ peptides and different hIAPP species (monomers, oligomers, and fibrils) using combined experimental and simulation approaches. Cross-seeding and propagation of different amyloid peptides monitored by experimental techniques proved that the three species of hIAPP aggregates have successively enhanced Aβ fibrillation, especially for hIAPP fibrils. Moreover, the polymorphism of these morphologically similar hybrid amyloid strains could be distinguished by testing their mechanical properties using quantitative nanomechanical mapping, where the assemblies of Aβ-hIAPP fibrils exhibited the high Young’s modulus. Furthermore, the enhanced internal molecular interactions and β-sheet structural transformation were proved by exploring the conformational ensembles of Aβ-hIAPP heterodimer and Aβ-hIAPP decamer using molecular dynamic simulations. Our findings pave the way for identifying different hybrid amyloid strains by quantitative nanomechanical mapping and molecular dynamic simulations, which is important not only for the precise classification of neurodegenerative disease subtypes but also for future molecular diagnosis and therapeutic treatment of multiple interrelated degenerative diseases.
Growth mechanisms in molecular beam epitaxy for GaN-(In,Ga)N core–shell nanowires emitting in the green spectral range
Authors: van Treeck David , Lähnemann Jonas , Brandt Oliver , Geelhaar Lutz
Published: August 2023

Using molecular beam epitaxy, we demonstrate the growth of (In,Ga)N shells emitting in the green spectral range around very thin (35 nm diameter) GaN core nanowires. These GaN nanowires are obtained by self-assembled growth on TiN. We present a qualitative shell growth model accounting for both the three-dimensional nature of the nanostructures as well as the directionality of the atomic fluxes. This model allows us, on the one hand, to optimise the conditions for high and homogeneous In incorporation and, on the other hand, to explain the influence of changes in the growth conditions on the sample morphology and In content. Specifically, the impact of the V/III and In/Ga flux ratios, the rotation speed and the rotation direction are investigated. Notably, with In acting as surfactant, the ternary (In,Ga)N shells are much more homogeneous in thickness along the nanowire length than their binary GaN counterparts.