bluuebunny/crossref_metadata_2025 huggingface dataset:
Homebuilt cost-effective nitrogen blowdown evaporator
Authors: Clarke Eamonn , Porter Marc D.
Published: January 2025

A nitrogen blowdown evaporator built with widely-available materials and techniques is described, accompanied by plans and detailed instructions for assembly. We show that the apparatus operates without causing contamination or sample loss.
Ultrarapid and efficient sequestration of iodate and iodide with a pillar[5]arene-based cationic polymeric network
Authors: Jiang Yongjie , Qi Yue , Yu Chengkan , Hu Liancheng , Li Qing , Li Xiaowei , Cai Yimin , Yuan Lihua , Feng Wen
Published: January 2025

A macrocycle-based approach to the construction of a cationic polymeric network with pillar[5]arene as a node for efficient sequestration of hazardous IO3− and I− is presented.
Rhodium/selenium dual catalysis for accessing 2-aminopyrroles from N-sulfonyl-1,2,3-triazoles
Authors: Pal Kuntal , Dash Om Prakash , Volla Chandra M. R.
Published: January 2025

A dual Rh(ii)/selenium catalysis strategy for accessing 2-aminopyrroles from N-sulfonyl-1,2,3-triazoles was illustrated. Selenium ylide, generated by the reaction of diselenide with Rh-azavinyl carbene, is key for the success of the transformation.
Surface analysis of thermally stable Pt loaded CeO2–ZrO2 using colloidal Pt for TWC application
Authors: Tanaka Hiroki , Endo Yoshinori , Haneda Masaaki
Published: January 2025

Colloidal Pt forms a small boundary with CZ, suppressing the aggregation of Pt in air. In contrast, a conventional Pt salt forms a larger boundary, enhancing catalytic performance after aging in N2 because Pt aggregation does not occur.
Mechanochemical pretreatment of tin iodide perovskite precursors: effects of grinding temperature and time on solar cell performance
Authors: Liu Tingting , Cho Sungwoon , Nishikubo Ryosuke , Pylnev Mikhail , Ishiwari Fumitaka , Wakamiya Atsushi , Saeki Akinori
Published: January 2025

We report the mechanochemical pretreatment of precursors for lead-free tin-based perovskite solar cells and highlight the effect of grinding temperature and time.
Bioaccessibility of bioactive compounds and associated compounds to the indigestible fraction after in vitro digestion of three dry Capsicum annuum varieties
Authors: Medrano-Ruiz Luis Gerardo , Molina-Domínguez Claudia Celeste , Rascón-Valenzuela Luisa Alondra , Dórame-Miranda Ramon Francisco , Osorio-Díaz Perla , Medina-Juárez Luis Ángel , Ovando-Martínez Maribel
Published: January 2025

Colorado, de Arbol and chiltepin, dry chilies rich in bioactive compounds (capsaicin, tocopherols and polyphenols), add special sensory properties to Mexican dishes. Such compounds after digestion show adequate bioaccessibility.
Machine learning prediction of physical properties of lignin derived porous carbon via catalytic pyrolysis
Authors: Xie Zihao , Cao Yue , Luo Zhicheng
Published: January 2025

Lignin-derived porous carbon produced through catalytic pyrolysis is crucial for energy storage, adsorption, and catalysis.
Synergistic binding ability of electrostatic tweezers and femtosecond laser-structured slippery surfaces enabling unusual droplet manipulation applications
Authors: Li Xinlei , Wang Chaowei , Chen Zhenrui , Chen Cunyuan , Zhu Suwan , Wu Dong , Yong Jiale
Published: January 2025

A novel contactless droplet manipulation strategy that combines electrostatic tweezers with lubricated slippery surfaces is developed, which features significant flexibility, high precision, and can work under various operating conditions.
An NIR-luminescent nitrate-bridged hybrid bimetal dielectric with a switchable dielectric constant
Authors: Wang Li-Ping , Jiang Lu-Lu , Cui Zong-Ze , Hu Zheng-Hui , Miao Le-Ping , Li Jian-Rong , Ye Heng-Yun , Shi Chao
Published: January 2025

A dynamic responsive hybrid bimetallic material (MQ)5[K2Nd2(NO3)13] (1; MQ = N-methylquinuclidinium cation) simultaneously exhibited switchable dielectric constant and near-infrared luminescence.
Relocating NSAIDs into the endoplasmic reticulum induces ER stress-mediated apoptosis in cancer cells
Authors: Mishra Tripti , Preeti  , Ingle Jaypalsing , Saha Aditi , Basu Sudipta
Published: January 2025

From a synthetic endoplasmic reticulum (ER)-targeted NSAID library, an ibuprofen derivative was identified to induce ER stress followed by autophagy to trigger apoptosis in HCT-116 colon cancer cells.
Insights into the electronic structure, optical properties, and photocatalytic potential of Gd2CoCrO6 perovskite: a comprehensive theoretical and experimental investigation
Authors: Hosen M. J. , Tarek M. , Bhuyan M. D. I. , Basith M. A. , Syed I. M.
Published: January 2025

This study investigates the electronic structure, optical properties, and photocatalytic potential of Gd2CoCrO6, revealing its half-metallic, n-type semiconducting behavior and suitability for solar-driven applications through theory and experiments.
ETL engineering in lead-free new Ca3PBr3 perovskite type structure of anti-perovskite derivative material for stable and effective photovoltaic solar cells
Authors: Rahman Md. Hafizur , Full Hosnaara , Rahman Md. Azizur , Ahmed Sheikh Rashel Al , Ben Farhat Lamia , Ezzine Safa , Rahman Md. Ferdous
Published: January 2025

This study explores the structural, electronic, mechanical, optical, and photovoltaic properties of the Ca3PBr3 anti-perovskite derivative material using DFT and SCAPS-1D simulations.
Molecularly imprinted polymer coupled with zinc-doped carbon quantum dots as a fluorescent probe for the determination of doxorubicin hydrochloride
Authors: Zhang Han , Fang Fang , Yi Jiangle , Sun Yuanling , Wang Xueying
Published: January 2025

Blue fluorescent carbon quantum dots (HCQDs) doped with Zn were synthesized using hair as the carbon source. Then, a fluorescent molecularly imprinted polymer (HCQDs@MIP) for the determination of DOX was synthesized.
A MOF-derived layered K-VO heterojunction material as a high-performance cathode for aqueous zinc ion batteries
Authors: Chen Guohua , Wang Liying , Liu Qian , Wang Yuan , Cao Zhenzhu , Zhang Yongfeng
Published: January 2025

A novel multilayer rhombohedral K0.5V2O5 and KVO3 heterojunction compound (3K-VO) was synthesized by calcining the MOF precursor as an excellent AZIB cathode material, achieving excellent electrochemical performance.
Effects of an electrospun Janus structure on enhanced UV resistance performance
Authors: Chen Bingying , Guo Junli , Chen Chen , Shen Yueling , Yang Yaoyao , Yu DengGuang
Published: January 2025

The Janus structure of nanofibers fabricated by electrospinning using eccentric spinneret enhances the UV resistance of Thermoplastic polyurethane (TPU) fabrics which often possess good mechanical, waterproofing, and breathability properties.
Nanoscale size impact of nanoparticle interaction and activity studies with urease
Authors: Bhardwaj Priya , Bisht Bhawana , Bhalla Vijayender
Published: January 2025

Interaction of urease with four different sizes (5–100 nm) of silver nanoparticles and inhibition studies.
Deciphering allosteric mechanisms in KRAS activation: insights from GTP-induced conformational dynamics and interaction network reorganization
Authors: Zhao De-Rui , Yang Ji-Tong , Liu Meng-Ting , Yang Li-Quan , Sang Peng
Published: January 2025

KRAS activation is driven by GTP binding, leading to increased flexibility and dynamic network reorganization. This study highlights the critical roles of switch I, switch II, and P-loop in mediating allosteric signaling pathways.
Cu(ii) binding to an antimicrobial shrimp peptide – a small step for structural chemistry, a big leap for medicinal applications
Authors: Miller Adriana , Matera-Witkiewicz Agnieszka , Mikołajczyk-Tarnawa Aleksandra , Kola Arian , Wiloch Magdalena , Jonsson-Niedziolka Martin , Wieczorek Robert , Wątły Joanna , Valensin Daniela , Rowińska-Żyrek Magdalena
Published: January 2025

PvHCt, a 23-aa AMP from shrimp, becomes strongly antimicrobial when Cu(ii) binds to its central and C-terminal regions, inducing a pronounced bend in the peptide backbone, increased α-helical content, and production of reactive oxygen species.
Ni-catalyzed regioselective and site-divergent reductive arylalkylations of allylic amines
Authors: Meng Huan , Jia Jun-Song , Yang Peng-Fei , Li Yu-Long , Yu Qiong , Shu Wei
Published: January 2025

A Ni-catalyzed cross-electrophile regioselective and site-divergent 1,2- and 1,3-arylalkylations of allylic amines has been developed, representing the first controllable migratory difunctionalization of alkenes under reductive conditions.
A fiber-shaped sensor constructed by coaxial wet-spinning for dual-mode sensing
Authors: Ma Duixin , Fang Huayang , Sun Jianping , Jiang Tao
Published: January 2025

This study made a skincore fiber sensor by co–axial wet spinning. It can accurately detect human movement and breathing due to its humidity and pressure response. Wireless signal modules were used for monitoring and interaction.
A reactive oxygen species amplifier based on a Bi2WO6/BP heterojunction for high efficiency radiotherapy enhancement
Authors: Ren Shufen , Zhang Qing , Fu Hanping , Cheng Jiayun , Xie Yan , Liang Qingshuang , Xiao Xiufeng
Published: January 2025

Insufficient reactive oxygen species (ROS) generation and radioresistance resulting from the intrinsic features of tumors consistently give rise to unsatisfactory therapeutic outcomes of radiotherapy (RT).
Injectable ultrathin porous membranes harnessing shape memory polymers for retinal tissue engineering
Authors: Jo SeongHoon , Kim Yu-Jin , Hwang Taek , Jang Se Youn , Park So-Jin , Ye Seongryeol , Jung Youngmee , Yoo Jin
Published: January 2025

Our research presents injectable porous membranes that mimic the key characteristics of Bruch's membrane, offering injectability and self-expandability at body temperature.
Liposome-encapsulated lambda exonuclease-based amplification system for enhanced detection of miRNA in platelet-derived microvesicles of non-small cell lung cancer
Authors: Benariba Mohamed Aimene , Hannachi Kanza , Wang Sanxia , Zhang Yuting , Wang Xiaoli , Wang Li , Zhou Nandi
Published: January 2025

Immunoliposomes with a λ EXO-based amplification system target platelet-derived microvesicles (PMVs) in NSCLC patients for ultrasensitive miRNA-21 detection.
Prospects for photon–phonon dressing and crystal-field non-Hermitian alignment of Eu3+:BiPO4
Authors: Usman Muhammad , Hussain Iqbal , Majeed Muhammad Kashif , Munir Faisal , Nadeem Faisal , Usmani Muhammad Waqas , Ahmad Irfan , Raza Faizan , Zhang Yanpeng
Published: January 2025

We report non-Hermitian energy level alignment via photon–phonon dressing quantization. We propose a spectral homogenizer based on four types of alignment, revealing that the reverse dressing effect induces this alignment.
1D Cs2AgBr3:Mn2+ crystals to realize high-resolution X-ray scintillation imaging
Authors: Chen Tao , Mu Dedan , Lin Feng , Tang Wenjun , Zhou Yuqing , Shi Xinyue , Li Changjiang , Jiang Xuekai , Li Xin , Chen Haiyuan , Chen Tao , Xu Xuhui , Wang Chong
Published: January 2025

Herein, Mn2+ doping as an effective method is employed to transform nearly non-luminescent Cs2AgBr3 crystals into strong green luminescent material for high-resolution X-ray scintillation imaging.
Fast calculation method of transformer harmonic magnetic field based on radial basis function augmented surrogate model
Authors: Gao Shuguo , Liu Haoyu , Zang Qian , Guo Meng , Liu Gang , Zhang Zhigang , Dai Lujian , Liu Yunpeng
Published: January 2025

Accurate and efficient calculation of a transformer's magnetic field is fundamental for the rapid calculation of its losses, temperature rise, and structural forces. However, existing numerical methods for calculating the harmonic magnetic field of a product‐level transformer are time‐consuming and fail to meet the rapid requirements of digital operations and maintenance. To address this, this paper first utilises the harmonic field method to obtain the snapshot matrix of the transformer's magnetic field. Subsequently, a response surface model of the magnetic field is constructed using intrinsic quadrature theory and radial basis functions in the augmented form. To enhance the efficiency of constructing the reduced‐order model, an adaptive Latin hypercube sampling method, integrating the additive rule and leave‐one‐out cross‐validation, is introduced, significantly improving the efficiency of sample space construction. The effectiveness of the proposed method is validated by applying the proper orthogonal decomposition‐radial basis function including linear polynomial (POD‐RBFLP) method to calculate the harmonic magnetic field of a three‐phase power transformer in reduced order. The results are compared with those from COMSOL calculations, showing that the reduced‐order model maintains the calculation error within a reasonable range, thereby confirming the accuracy of the proposed method. Additionally, the reduced‐order model demonstrates a significant advantage in computation time compared to COMSOL simulations, enabling the calculation of the transformer's magnetic field in seconds.
A stellar census in globular clusters with MUSE
Authors: Latour M. , Kamann S. , Martocchia S. , Husser T.-O. , Saracino S. , Dreizler S.
Published: January 2025

Context. Multiple populations are ubiquitous in the old massive globular clusters (GCs) of the Milky Way. It is still unclear how they arose during the formation of a GC. The topic of iron and metallicity variations has recently attracted attention with the measurement of iron variations among the primordial population (P1) stars of Galactic GCs.

Aims. We explore the relationship between the metallicity of the P1 stars on the red-giant branch (RGB) of Galactic GCs and their ∆F275W,F814W pseudo-color. We also measure the metallicity dispersion of P1 and P2 stars.

Methods. We used the spectra of more than 8000 RGB stars in 21 Galactic GCs observed with the integral-field spectrograph MUSE to derive individual stellar metallicities, [M/H]. For each cluster, we used Hubble Space Telescope photometric catalogs to separate the stars into two main populations (P1 and P2). We measured the metallicity spread within the primordial population of each cluster by combining our metallicity measurements with the stars’ ∆F275W,F814W pseudo-color. We also derived metallicity dispersions (σ[M/H]) for the P1 and P2 stars of each GC.

Results. In all but three GCs we find a significant correlation between the metallicity and the ∆F275W,F814W pseudo-color of the P1 stars: stars with larger ∆F275W,F814W have higher metallicities. We measure metallicity spreads that range from 0.03 to 0.24 dex and correlate with the GC masses. As for the intrinsic metallicity dispersions, when combining the P1 and P2 stars, we measure values ranging from 0.02 dex to 0.08 dex, which correlate very well with the GC masses. The two clusters that show the largest σ[M/H] are NGC 6388 and NGC 6441. The P2 stars have metallicity dispersions that are smaller than or equal to those of the P1 stars.

Conclusions. We present a homogeneous spectroscopic characterization of the metallicities of the P1 and P2 stars in a set of 21 Galactic GCs. We find that both the metallicity spreads of the P1 stars (from the ∆F275W,F814W spread on the chromosome maps) and the metallicity dispersions (σ[M/H]) correlate with the GC masses, as predicted by some theoretical self-enrichment models presented in the literature.
Atmospheric dynamics of the hypergiant RW Cep during the Great Dimming
Authors: Kasikov A. , Kolka I. , Aret A. , Eenmäe T. , Borthakur S. P. D. , Checha V. , Mitrokhina V. , Yang S.
Published: January 2025

Context. The hypergiant RW Cep is one of the largest stars in the Galaxy. The evolution and mass loss of such stars have profound effects on their surrounding regions and their galaxy as a whole. Between 2020 and 2024, RW Cep experienced a historic mass-loss event known as the Great Dimming.

Aims. This study provides a spectroscopic analysis of RW Cep during the Great Dimming. We examine its atmospheric dynamics and place it in the context of the star’s variability behaviour since the early 2000s.

Methods. We conducted high-cadence spectroscopic observations of RW Cep during the dimming event using the Tartu Observatory 1.5-meter telescope and the Nordic Optical Telescope. We analysed the atmospheric dynamics by measuring the radial velocities and line depths of Fe I and other spectral lines.

Results. The radial velocities of the Fe I lines reveal a vertical velocity gradient of 10–20 km s−1 in the atmosphere, correlating with the strength of the spectral lines. Stronger lines, formed in higher atmospheric layers, have higher radial velocities. We measured the systemic velocity at −50.3 km s−1. During the dimming, radial velocities were affected by additional emission from the ejected gas, which was blue-shifted relative to the absorption lines. Post-dimming, we observed large-scale atmospheric motions with an amplitude of ~25 km s−1. Strong resonance lines of Ba II, K I, Na I, and Ca I showed stable central emission components at −56 km s−1, which are likely of circumstellar origin.
Leveraging Unity for 2D Pixel Game Development: Techniques and Best Practices
Authors: Wang Ke
Published: January 2025

The rapid evolution of game development technologies emphasizes the demand for high-quality graphics and immersive gameplay. Meanwhile, there has also been a pixel art revival in the game development industry. This research explores the process of creating a 2D pixel-art adventure game with the Unity engine, figuring out some common problems that developers face and efficient solutions to them. To address these problems, the research uses several powerful toolsets offered by Unity and some other efficient approaches. This paper makes a 2D pixel-art game as a case study, focusing on the challenges of animations, map design, and gameplay mechanics. This paper found an innovative 3D-to-2D animation workflow, allowing developers to create better animations with less time. By applying Unity’s tool Tilemap Editor, this paper also found an efficient way to design levels. Additionally, this research offers some suggestions on how to improve game mechanics. The findings underscore the importance of consistent visual design and thorough playtesting. This research contributes to pixel-art games by providing practical solutions for game developers and demonstrates the potential of the Unity engine.
Deep Learning Based DDoS Attack Detection
Authors: Xu Ziyi
Published: January 2025

Nowadays, one of the biggest risks to network security is Distributed Denial of Service (DDoS) assaults, which cause disruptions to services by flooding systems with malicious traffic. Traditional approaches to detection, based on statistical thresholds and signature-based mechanisms, respectively, can hardly cope with the increasing complexity of such an attack. In order to improve detection accuracy and generalization, this research suggests a deep learning-based detection model that combines the Long Short-Term Memory (LSTM) network architecture with Convolutional Neural Networks (CNN). On the CICDDoS2019 dataset, which included several DDoS attack versions, the suggested model was trained and evaluated. The hybrid CNN-LSTM has extraction capabilities regarding both the spatial and temporal features of network traffic data, showing highly efficient performance. The classification resulting from this model yielded high accuracy with robust results for different attack scenarios. Results reflect the potential superiority of the given model in detecting DDoS attacks. Even though the performance was sound, the model still showed certain shortfalls, which were revealed when particular types of attacks were tested. Future work may be directed at further refining the model architecture, including optimizing diversity in training to allow for even better detection capabilities.
Research for SARIMA and PatchTSMixer Models on the IEA Monthly Statistics Dataset
Authors: Hu Yuwei
Published: January 2025

The rapid evolution of intelligent algorithms has led to their extensive application in time-series forecasting, particularly in predicting electricity consumption. Accurate forecasting is crucial for energy management, policy-making, and ensuring a stable power supply. However, a significant gap exists in comparing the predictive performance of traditional machine learning methods with advanced deep learning models using real-world datasets. This study aims to address this gap by evaluating and comparing the prediction accuracy of machine learning and deep learning techniques using the Monthly Electricity Statistics dataset from the International Energy Agency (IEA). The research employs a rigorous experimental design, leveraging models such as ARIMA and PatchTSMixer, with an emphasis on model tuning and performance metrics like MAE, MAPE, and RMSE. The findings reveal that deep learning models, particularly PatchTSMixer, outperform traditional machine learning methods in terms of prediction accuracy, demonstrating their superior capability in capturing complex temporal dependencies in electricity consumption data. These results highlight the potential of deep learning models for enhancing predictive accuracy in time-series forecasting, providing valuable insights for future research and practical applications in energy management.
The Application and Analysis of Emotion Recognition Based on Modern Technology
Authors: Bi Lanxin
Published: January 2025

This article provides a comprehensive analysis of various emotion recognition methods, focusing on speech emotion recognition, facial expression recognition, and physiological signal emotion recognition. The primary aim is to evaluate the advantages and disadvantages of these methods, offering insights into selecting the most appropriate approach for different application scenarios. The study involves collecting and analysing experimental data, exploring their respective strengths and limitations, and proposing potential solutions to enhance their effectiveness. Speech emotion recognition is effective but sensitive to noise and speaker variability, while facial expression recognition excels under controlled conditions but struggles with changes in lighting and angles. Physiological signal recognition offers deep insights into internal emotional states but requires complex signal processing and is vulnerable to external interferences. Despite the growing application of emotion recognition technology across various fields, including healthcare, traffic safety, and security, there remain significant challenges related to accuracy, robustness, and privacy. This study highlights the need for continued research to improve these technologies, particularly in enhancing their robustness and adaptability. The findings provide valuable guidance for researchers and practitioners seeking to optimize emotion recognition systems for diverse real-world applications.
Novel 4,5-seco-Abietane-Type Diterpenes from Salvia prattii
Authors: Li Yan-Ling , Xiong Fei-Fei , Zhou Yu , Xia Fan , Xu Gang
Published: January 2025

Eight new 4,5-seco-abietane-type diterpenes, salpratones B–I, along with two analogues, featuring diverse 6/5/6, 6/6/6, 6/6/7, and 6/6/8 ring systems, were isolated from Salvia prattii. Notably, salpratone B is the first example of a 4,5;13,14-bis-seco-abietane diterpene characteristic with a rare rearranged 6/5/6 tricyclic core skeleton. Their structures were determined by comprehensive NMR spectroscopy, single-crystal X-ray diffraction, and electronic circular dichroism. Moreover, salpratones B–D were resolved into optically pure enantiomers. Partial diterpenes were evaluated for their in vitro anticoagulant activities. While salpratones B, E, F can weakly prolong the clotting times of human plasma in the activated partial thromboplastin time (APTT) assays with concentrations of 100 μM, showing no appreciable anticoagulant activities.
Thermodynamics of low-dimensional magnetic systems (A review)
Authors: Antsygina T. N. , Slyusarev V. A.
Published: January 2025

In this review we cover the most interesting and, as we think, important results that are related to the problem of low-dimensional magnetism. We concentrate mainly on the thermodynamic properties of one- and two-dimensional isotropic Heisenberg magnetic materials. The strong and weak points of the various theoretical approaches used currently for the description of these systems are discussed in detail.
Low-frequency ohmic losses in high-temperature superconductors
Authors: Dmitriev V. M. , Ofitserov M. N. , Prentslau N. N. , Rogacki K. , Sadowski W.
Published: January 2025

In the example of high-Tc superconductors of the type (RE)Ba2Cu3Ox (RE denotes rare-earth metals), and also thallium and bismuth ceramics, it is shown that the phenomenon of anomalous growth of the ohmic loss resistance in a certain frequency interval is a general property of these types of materials. This property of high-Tc. superconductors is observed in both the normal and the superconducting state. The anomalous resistance characteristics common to both states are described, along with their differences in the normal and superconducting states. It is found that superconductivity is suppressed in the frequency interval where the anomaly exists, but is partially restored in a static magnetic field in ceramics containing magnetic impurities.
Electron spectrum and critical temperature of HTS materials with several cuprate layers in a cell
Authors: Gorbar E. V. , Loktev V. M. , Sharapov S. G.
Published: January 2025

The equations for superconducting gaps, the critical temperature Tc, and the chemical potential as functions of charge carrier concentration and the number of layers in a multilayered metal are obtained on the basis of the model microscopic Lagrangian of the multilayered system of Fermi particles with attraction. It is shown that the filling of energy bands of free charge carriers can lead to the emergence of regions with a sharp increase in the gap width and in Tc upon an increase in the carrier density in the system. The Cooper and local pairs of carriers coexist in the system, leading to a nonmonotonic increase in Tc of a multilayered conductor. This effect is observed, for example, in the bilayered compound YBa2Cu3 O6+δ with varying δ.
Radiative transitions in solid C60 under UV laser and VUV synchrotron radiation
Authors: Terekhin M. A. , Svechnikov N. Yu. , Kolmakov A. A. , Stankevitch V. G. , Stepanov V. A. , Bezmelnitsin V. N. , Kamada M. , Tanaka S. , Kan’no K. , Ashida M. , Matsumoto T.
Published: January 2025

Photoluminescent properties of pure C60 thin solid films have been investigated in the emission range of 1.2–2.4 eV over a wide temperature interval under excitations with 3.7 and 36 eV photons. Dose dependence of the luminescence degradation of C60 films under long-time UV and VUV irradiation has been discovered and examined at various ambient conditions. Temperature dependence of luminescence from 10 to 300 K exhibited a step-like peculiarity in the vicinity of the structural phase transition near Tc∼250 K, and a decrease from 13 to 10 K. Also a C60 luminescence in the process of doping by neutral potassium atomic beam in situ at 400 K has been examined. The luminescence decay time measurements gave values of 1.2±0.1 ns for a singlet excited state, and ∼400 microseconds for a triplet state, the latter decays non-radiatively with a probability of more than 80%. The experimental data obtained lead us to a conclusion that the intrinsic nature of luminescence in solid C60, correlates with the bulk properties which may be attributed, mainly, to self-trapped singlet excitons. The influence of the triplet state was also observable via protection against photopolymerization due to energy transfer from the excited triplet state of C60 to intercalated dioxygen.
On the nature of infrared absorption anomalies in small particles of high-temperature superconductors
Authors: Blank A. Ya. , Pashitskiĭ È. A.
Published: January 2025

Infrared (IR) absorption in a small-particle ensemble of high-temperature superconducting (HTS) materials based on layered cuprate metal-oxide compounds (MOC) is considered in the quasi-static approximation, taking into account strong anisotropy in the permittivity of individual particles. It is shown that anisotropy in effective masses and plasma frequencies of charge carriers in particles leads to the emergence of two resonance absorption bands in the near and far IR regions. The calculated positions of peaks are in good agreement with experimental data. The observed absence of reflection of IR radiation at a layer of small particles is explained by the mechanism proposed for exciting intrinsic modes of dipole oscillations of charge carriers in small HTS particles.
The diode percolation model of vortex flow in the resistive state of HTS films
Authors: Snarskiĭ A. A. , Pashitskiĭ È. A. , Palti A. M.
Published: January 2025

The behavior of IVC in the initial region of the resistive state of HTS films, which follows a power law in contrast to the exponential behavior of IVC for low-temperature superconductors, is explained theoretically. Depinning of vortices in type II layered superconductors with a continuous distribution of pinning forces (in a certain finite interval) is described on the basis of a model of percolation structure constructed for the so-called diode percolation. This model is used for calculating the universal critical exponent γ of the power IVC E ∼ (j–jc)γ, which can be expressed in terms of the known critical indices ν⊥ for correlation length and t+ for conductivity in the 2D diode percolation theory (γ = 2ν⊥ – t+). The numerical value of the universal index γ ≈ 1.6 is in satisfactory agreement with the recent experimental value γ ≈ 1.3–1.5.
Electron combination scattering of light in conductors with magnetoimpurity states
Authors: Ermolaev A. M. , Rashba G. I. , Shurduk A. I.
Published: January 2025

The differential cross section for inelastic scattering of light by single-particle and collective excitations in conductors with magnetoimpurity electron states is calculated. New series of lines are observed in the energy spectrum of scattered radiation. The cross sections are calculated numerically for semimetals and degenerate semiconductors.
Stationary states of a quasi-one-dimensional magnetic system with “comb” structure
Authors: Ezerskaya E. V.
Published: January 2025

Stationary states of a quasi-one-dimensional spin system with “comb” structure and with XY-exchange interaction along the chain and Ising interaction of “teeth” (J>0) are considered. The existence of bound states of an arbitrary number n of inverted spins in the “teeth” and a single state in the XY-chain is proved. For a positive constant of Ising exchange interaction, the energies of these states lie below the energies of the corresponding states in the continuous spectrum. For n⩾2, the energies of these states depend on the mutual arrangement of inverted spins in the “teeth.”
Tuning and modeling nanoparticles with flexible cores
Authors: Lange Katherine De
Published: January 2025

Tunable and responsive coarse-grained models enable accurate simulations of flexible nanoparticles, especially significant in biomedical applications
Temperature-dependent optical constants of nanometer-thin flakes of Fe(Te,Se) superconductor in the visible and near-infrared regime
Authors: Pattanayak Aswini K. , Rout Jagi , Jha Pankaj K.
Published: January 2025

Iron chalcogenide superconductors, such as Fe(Te,Se), have recently garnered significant attention due to their simple crystal structure with a relatively easy synthesis process, high-temperature superconductivity, intrinsic topological band structure, and an unconventional pairing of superconductivity with ferromagnetism. Here, we report the complex in-plane refractive index measurement of a nanometer-thin Fe(Te,Se) flake exfoliated from a single crystal FeTe0.6Se0.4 for photon wavelengths from 450 to 1100 nm over a temperature range from 4 to 295 K. The results were obtained by employing a two-Drude model for the dielectric function of Fe(Te,Se), a multiband superconductor, and fitting the absolute optical reflection spectra using the transfer matrix method. A high extinction coefficient in the visible to near-infrared range makes nanometer-thin Fe(Te,Se) flakes a promising material for photodetection applications.
State of the art and outlook of energy tunnels: Design, construction, and thermal systems
Authors: Wang Yongyan , Zhou Guobing , Liu Jun , zhang Hanfei , Wang Fuqiang , Qiao Guogang , Desideri Umberto , Xu Baoping , Wang Xi
Published: January 2025

Energy tunnel is thermally activated through embedding absorber pipes within the tunnel lining, where the underground heat is extracted and transferred above the ground via a heat pump for building energy applications. Energy tunnel offers advantages such as low carbon emissions, cleanliness, high efficiency, and safety. The heat source can be either outside or inside the tunnel. This article first categorizes energy tunnels into external and internal heat source energy tunnels, describes the characteristics of the environment inside and outside of these tunnels and their methods of construction, and some practical projects. Subsequently, the energy utilization systems with different heat sources are analyzed, underlining the critical role of heat transfer process being closely linked to the arrangement of absorber pipes with different heat sources. Factors affecting the heat transfer performance are then reviewed and the measures to enhance heat transfer are systematically discussed. Finally, the future study and application of different types of energy tunnels are proposed. Current research studies on energy tunnels primarily focus on transportation and mining tunnels, extracting geothermal energy generated outside the tunnels. However, studies and application of waste heat within energy tunnels are currently insufficient. Moreover, the design of natural geothermal energy collection, structural safety of the tunnel facilities, along with concerns regarding condensate water generated within the energy tunnel, necessitate further investigations.
A gigawatt-level metamaterial-based relativistic transit-time oscillator with coaxial energy extraction
Authors: Pi Mingyao , He Juntao , Wang Lei , Xu Weili , Zeng Fanbo , He Yufang , Ding Bin , Song Hao , Ling Junpu
Published: January 2025

This manuscript presents a 2 + 2 metamaterial (MTM) transit-time oscillator (TTO) employing coaxial extraction, engineered to leverage the advantages of MTM and TTO. Cold cavity testing was conducted to examine the electromagnetic properties of the MTM resonator, revealing that at least 1/3 of the radial size can be reduced compared to traditional designs. Comparison of various energy extraction techniques has also been conducted, highlighting the effectiveness of coaxial method over other axial schemes. Computational simulations with electron beams, conducted under parameters of 650 kV, 5.36 kA, and 1.2 T magnetic field, yields a 1 GW microwave output at 1.54 GHz, exhibiting a stable, single mode without competition. This MTM integration significantly reduces the diode impedance in high-power microwave devices, resulting in a shorter axial length and achieving GW-level power output. This design suggests a potential step forward for MTM-based high-power microwave sources, offering the possibility of greater power density and compactness, and may contribute to the advancement of MTM applications in electron vacuum technology.
Sub-terahertz PAM4 modulator based on transmission characteristic reconstruction
Authors: Ding Kesen , Bi Chunyang , Ao Yu , Cheng Liyu , Fang Hailong , Dong Yazhou , Zhou Hongji , Wang Xun , Zhang Zhenpeng , Liang Shixiong , Gong Sen , Zhang Yaxin
Published: January 2025

In this paper, we propose a sub-terahertz PAM4 modulator based on transmission characteristic reconstruction by combining meta-unit, GaAs Schottky diode, and fan branch lines. This method combined the significant electromagnetic resonant characteristics of meta-unit, the high-speed controllability of GaAs Schottky diode, and the high integration of on-chip transmission line together to realize high-speed modulation. Then, we achieve transmission characteristic reconstruction by adjusting the resonance strength under different applied voltages through fan branch lines, enabling high-order amplitude modulation of sub-terahertz waves. The experimental results show that the PAM4 modulation of sub-terahertz waves is achieved with a nearly linear variation of the transmission coefficient in the whole voltage range and a maximum modulation rate of 21 Gbps, providing a promising prospect for the development and application of integrated sub-terahertz direct high-order modulation technology.
Computational investigation of moving shock interaction with a granular particle curtain using a coupled Eulerian–Lagrangian approach
Authors: Bajpai Aasheesh , Wangikar Aaditya U. , Tewari Chetan , Kumar Rakesh
Published: January 2025

The objective of this research is to investigate the influence of a moving shock wave on a dense particle curtain using a coupled supersonic Eulerian–Lagrangian solver. The numerical investigation seeks to gain a deeper understanding of the interactions between particles and gas flow through a four-way coupling approach that incorporates interparticle collisions. Upon interaction, the particle curtain undergoes rapid expansion, generating transmitted and reflected shocks. This work focuses on how different particle arrangements affect the fluid flow dynamics and vice versa. By systematically varying the shock Mach number, we elucidate the effects of these interactions across a range of shock strengths, providing a comprehensive picture of the phenomenon. Our findings reveal the crucial role of particle properties and interparticle forces in shaping the dynamics of shock–granular interactions, paving the way for a deeper understanding of multiphase shock flows in various applications.
Multi-scale approach: Structure–texture relationship of meat and meat analogues
Authors: Wilhelm Elle Ina , Fritzsche Luiza , Hundschell Christoph Simon , Vilgis Thomas A. , Schmelzeisen David Olivier , Wagemans Anja Maria
Published: January 2025

Plant-based meat analogues are considered a sustainable substitute for meat. However, the current attempts to reproduce the visible fibrous structure on a macro scale (1 mm) have not yet achieved the desired texture properties. The role of the meso-scale fiber structure (50–200 μm) in the meat texture remains uncertain. To characterize the texture properties, this study employed Warner–Bratzler shear force tests and texture profile analysis, comparing cuts that were parallel and perpendicular to the fiber direction. Scanning electron microscopy was employed for the purpose of structural characterization. Anisotropy and texture properties were observed to differ between the meat and the meat analogues. The meat exhibited a fibrous structure at both the macro and meso scales, while the meat analogues displayed a porous structure without a clear fiber direction from the meso scale onward. The texture of meat is primarily determined by the connective tissue and muscle fibers, whereas the texture of meat analogues is mainly influenced by the fibers. This study elucidates the structure–texture relationships of meat and meat analogues at macro and meso scales, developing a mechanistic model to explain their differing responses to mechanical stress. These findings are crucial for improving the texture properties of meat analogues, advancing their ability to mimic meat's texture.
Experimental study on the unsteady characteristics of flow evolution for two vehicles with ventilated partial cavitation
Authors: Yu DeLei , Wei YingJie , Hu JianYong , Xia WeiXue
Published: January 2025

The object of this article is two parallel underwater vehicles with ventilated partial cavitation, which results in partial deformation of the ventilated cavity and is accompanied by nonlinear changes in the internal flow structure. In our experiments, a high-speed camera system was used to observe transient cavity evolution, and dynamic pressure measurement systems were employed to measure pressure fluctuations under different ventilation flow rates and parallel distances. The results indicated that cavity evolution goes through three stages after ventilation begins: the growth stage, the shortening stage, and the periodic shedding stage, with their periods being influenced by different variables. The dominant frequencies of grayscale variation in the three stages are significantly different, as are the pressure variations. Moreover, the dominant frequency of periodic shedding in the two cavities decreases as ventilation flow rates increase. A critical distance of d* = 1.6 was identified under the experimental conditions, which differentiates the pressure fluctuation characteristics at different parallel distances. Furthermore, the two main mechanisms of pressure fluctuation during the periodic shedding stage were clarified.
Effect of Cr/Al ratio on the microstructure and mechanical properties of CoFeNiCrxAl1−x high-entropy alloys
Authors: Song Hongquan , Feng Chuangshi , Guan Zhou , Zhang Wei , Yang Hengyong , Tang Yu , Zeng Kai , Yuan Xin , Zhang Jiawei , Liu Jia , Zhang Fuxiang
Published: January 2025

Achieving strength-ductility and functional integration is a key issue to promote the application of alloys in the field of functional materials. CoFeNiCrxAl1−x alloys exhibit excellent magnetic and corrosion resistance properties; however, their mechanical properties remain underexplored and insufficiently understood. In this work, the microstructure and mechanical properties of CoFeNiCrxAl1−x alloys were investigated, and their intrinsic deformation mechanisms were elucidated. The results indicate that as Cr is gradually replaced by Al, the phase structure transforms from a single-phase face-centered cubic (FCC) structure to a dual-phase FCC and body-centered cubic (BCC), and finally to a BCC/B2 structure. Mechanical tests demonstrated that alloy hardness rises with higher Al content, with the Cr0Al1 alloy exhibiting a hardness approximately 3.3 times greater than that of the Cr1Al0 alloy. Notably, the Cr0.5Al0.5 alloy exhibits an optimal strength-ductility balance, with a yield strength increase in about 60% to 248 MPa and tensile strength increase in about 36% to 610 MPa, while maintaining nearly the same ductility as the Cr1Al0 alloy. The deformation mechanisms were found to be driven by solid solution strengthening due to severe lattice distortion, a high dislocation density resulting from reduced dislocation formation energy, the second-phase strengthening and interface strengthening via the micrometer-scale BCC phase, and twin-induced plasticity induced by the reduced stack fault energy. This work broadens the potential applications of CoFeNiCrxAl1-x alloys as versatile engineering and magnetic functional materials.
Aerodynamic noise in the near and far fields beneath the leading car of high-speed trains
Authors: Qin Deng , Li Tian , Zhang Jiye
Published: January 2025

Research on train radiated noise typically focuses on turbulent pressure fluctuations and far-field predictions, neglecting the spatial sound field and bogie noise contributions. This study employs a subdomain approach to simulate noise from the head car and leading bogie of a high-speed train, utilizing the improved delay detached eddy simulation method for turbulent field analysis and the acoustic perturbation equation alongside the Ffowcs Williams–Hawkings equation for noise prediction. Results indicate that airflow adheres to the head car surface, while the bogie bottom displays complex streamlines with turbulence and vortices, particularly around the wheelsets. The irregular airflow and high-pressure fluctuations within the bogie cavity make it a significant source of aerodynamic noise, with elevated total and sound pressure levels in the rear structure and downstream areas. Noise primarily originates from the front and rear wheelsets, peaking at 110 and 245 Hz. Sound pressure waves propagate spherically, with strong disturbances at the bogie's rear and downstream cavity. The train structure diminishes sound pressure waves upstream and downstream, with greater strength on the sides. The leading bogie is the main source of far-field radiation noise, with substantial contributions from the car body. Most noise energy is concentrated below 800 Hz. The results highlight the importance of modeling and predicting aerodynamic noise in the underneath region of high-speed trains to facilitate a more comprehensive identification of noise sources.
Structural evolution of particle configurations: Zero-temperature phases under increasing confinement
Authors: Apolinario S. W. S.
Published: January 2025

In this study, we investigate the phase behavior and structural organization of colloidal particles in a two-dimensional (2D) system under isotropic harmonic confinement using overdamped Langevin dynamics simulations. We employ a modified mermaid potential, which introduces an additional short-distance term resulting in a null-force region, distinct from the conventional mermaid potential. This modification facilitates a richer exploration of self-assembled structures, revealing a variety of phases influenced by the interplay between confinement strength V0 and the interaction potential. Our analysis spans a wide range of parameters, resulting in a detailed phase diagram that captures transitions from dispersed clusters to well-ordered patterns, including square, triangular, rhomboidal, and mixed configurations, as the confinement strength increases. The findings underscore the intricate balance of forces governing the self-assembly of colloidal systems and offer valuable insights for future experimental realizations.
An offline coupling of fire spread models to simulate the 2021 Marshall Fire
Authors: Szasdi-Bardales Fernando , Shamsaei Kasra , Juliano Timothy W. , Kosovic Branko , Ebrahimian Hamed , Elhami-Khorasani Negar
Published: January 2025

Background Existing fire spread models focus exclusively on wildland or urban fire simulation. Aims This study aims at an offline coupling of two fire spread models to enable a continuous simulation of a wildfire incident transitioning from wildland into wildland–urban interface (WUI) communities, evaluate the effects of wind input on simulation results and study the influence of building types on fire spread patterns. Methods The selected models are WRF-Fire, a wildland fire behaviour simulation platform, and SWUIFT, a model for fire spread inside the WUI. The 2021 Marshall Fire serves as the case study. A map of the fire’s timeline and location is generated using public information. Three simulation scenarios are analysed to study the effects of wind input resolution and building type on the predicted fire spread and damage. Key results The most accurate results are obtained using a high-resolution wind input and when incorporating different building types. Conclusions The offline coupling of models provides a reliable solution for fire spread simulation. Fire-resistant buildings likely helped limit community fire spread during the Marshall Fire. Implications The research is a first step toward developing simulation capabilities to predict the spread of wildfires within the wildland, WUI and urban environments.