bluuebunny/crossref_metadata_2025 huggingface dataset:
Optoelectronic synapse based on the Bi2O2Se/Cs3Cu2I5 heterojunction for neuromorphic computing
Authors: Lin Jinwen , Li Bin , Yin Zheng , Wan Sicheng , Meng Yao , Zhou Hong , Gao Fangliang , Li Shuti , Zhang Yong , Zha Qingbing , Li Jinhua , Khisro Said Nasir , Chen Xinman
Published: January 2025

In this work, we report an optoelectronic synapse based on the Bi2O2Se/Cs3Cu2I5 heterojunction formed by consequently depositing Bi2O2Se and Cs3Cu2I5 thin films by chemical vapor deposition methods. The fabricated Au/Bi2O2Se/Cs3Cu2I5/Au devices exhibit the light-tunable photoresponse under visible light illumination. Synaptic functions including paired-pulse facilitation, the transition from short-term plasticity to long-term plasticity, associative learning and optical encoding, are conveniently reproduced on one single synaptic device by utilizing the light-tunable evolution of photocurrent. Furthermore, the front-end image preprocessing to enhance the accuracy and efficiency of image recognition was demonstrated based on the constructed device array (5 × 7). This indicates the potential application of Bi2O2Se/Cs3Cu2I5 optoelectronic synapses for the forthcoming neuromorphic computing.
Generation of non-diffracting vortex beams by an Archimedean spiral plate
Authors: Zeng Jiongchao , Zhao Qi , Yao Jun , Ma Zixian , Peng Lu , Liu Yidong , Yang Yuanjie
Published: January 2025

The non-diffraction beams are featured with maintained phase and intensity profiles, which have been utilized in various fields. Previous approaches for producing non-diffraction beams focused on designed cubic optical elements, resulting in limitations for integrated applications. Here, we design a mask with a binary Archimedean spiral structure for generating a high-order non-diffraction vortex beam. The produced plate imparts a conical phase to the incident beam, enabling the modulated beam to possess the characteristics of a Bessel wave, i.e., the spiral phase, non-diffraction, and self-healing. This mask may find promising applications, e.g., optical communication and imaging.
Experimental and computational evaluation of alpha particle production from laser-driven proton–boron nuclear reaction in hole-boring scheme
Authors: Huault M. , Carrière T. , Larreur H. , Nicolaï Ph. , Raffestin D. , Singappuli D. , D'Humieres E. , Dubresson D. , Batani K. , Cipriani M. , Filippi F. , Scisciò M. , Verona C. , Giuffrida L. , Kantarelou V. , Stancek S. , Boudjema N. , Lera R. , Pérez-Hernández J. A. , Volpe L. , Rodríguez Frías M. D. , Bonasera A. , Rodrigues M. R. D. , Ramirez Chavez D. , Consoli F. , Batani D.
Published: January 2025

The majority of studies on laser-driven proton–boron nuclear reaction is based on the measurement of α-particles with solid-state nuclear tracks detector (Cr39). However, Cr39's interpretation is difficult due to the presence of several other accelerated particles which can bias the analysis. Furthermore, in some laser irradiation geometries, cross-checking measurements are almost impossible. In this case, numerical simulations can play a very important role in supporting the experimental analysis. In our work, we exploited different laser irradiation schemes (pitcher–catcher and direct irradiation) during the same experimental campaign, and we performed numerical analysis, allowing to obtain conclusive results on laser-driven proton–boron reactions. A direct comparison of the two laser irradiation schemes, using the same laser parameters is presented.
High-efficiency perovskite light-emitting diodes enabled by introducing a LiF modification layer
Authors: Xue Xulan , Zhao Zhibo , Zhang Huidan , Lin Xingchen , Ning Yongqiang , Wang Lijun , Ji Wenyu , Zhu Hongbo
Published: January 2025

Surface defect passivation and exciton regulation remain a critical challenge in perovskite light-emitting diodes (PeLEDs). Organic molecules are widely used to solve these issues. However, the high sensitivity of perovskite films to the molecular groups and concentration limited their commercialization applications. Here, we develop a facile and low-cost passivation strategy that is compatible with traditional fabrication processes of PeLEDs. By depositing a thin LiF layer using vacuum thermal evaporation technique, the defects of perovskite film are effectively passivated. Simultaneously, the thin LiF layer protects the excitons formed in perovskite from quenching by the electron-transport layer. Due to the synergistic effect of LiF, an efficient green PeLED is achieved with a maximum current efficiency of 47.0 cd/A and luminance of 30 280 cd/m2, representing respective 65% and 166% increase than that of the control device without LiF modification layer (28.5 cd/A and 11 380 cd/m2). Our work provides an effective strategy and deep understanding of the interface regulation for achieving high-performance PeLEDs.
Effect mechanism of inlet elbow on energy consumption of large low-head pumping system and its optimization design
Authors: Yan Tianxu , Qiu Baoyun , Yuan Jianping
Published: January 2025

To investigate the effect of inlet elbow geometry on the performance of a large low-head pumping system and improve its comprehensive performance, this paper calculated and analyzed the internal flow fields, external characteristics, and entropy production distribution of the pumping system with different parametric combinations of the inlet elbow via numerical simulations with a Reynolds averaged Navier Stokes-volume of fluids fixed net head method. The energy characteristics were further studied using a newly introduced method of local internal energy change to visualize energy consumption. An automatic multi-software optimization design method was developed based on MATLAB, a feed-forward neural network, and a differential evolution algorithm to optimize the geometrical parameters of the inlet elbow. The research results indicate that appropriate heights of the throat and truncated cone improve velocity distribution, decrease the hydraulic loss in the inlet conduit, and foster a favorable flow condition at the pump inlet and outlet. Well-distributed axial velocity at the impeller inlet improves the pump efficiency. Well-distributed axial velocity and circulation at the pump outlet could reduce and eliminate flow separation, reflow, and vortices in the outlet conduit, thereby reducing energy consumption. Compared with the original design, the optimized geometry of the inlet elbow significantly improves the pumping system efficiency by 8.4 percentage points. The findings reveal the effect of the inlet elbow geometry on the performance of large low-head pumping systems and provide an easy, efficient, and economical method for the design and modification of low-head pumping systems.
Reliability of NiO/β-Ga2O3 bipolar heterojunction
Authors: Gong Hehe , Yang Xin , Porter Matthew , Yang Zineng , Wang Bixuan , Li Li , Fu Lan , Sasaki Kohei , Wang Han , Gu Shulin , Zhang Rong , Ye Jiandong , Zhang Yuhao
Published: January 2025

Ultra-wide bandgap (UWBG) NiO/β-Ga2O3 p–n junction has recently emerged as a key building block for emerging electronic and optoelectronic devices. However, the long-term reliability of this bipolar junction remains elusive. Here, the temporal evolution of the transient parametric shift is characterized in this junction under the prolonged forward- and reverse-bias stresses as well as in the post-stress recoveries. The temperature-dependent evolutions reveal the energy level and time constant of the dominant trap. The forward-bias stress is found to induce a negative turn-on voltage (VON) shift, the magnitude of which correlates with the stressed current density, while the reverse-bias stress leads to the opposite effect. Such VON shift is induced by an electron trap with an activation energy of 0.46 eV, which may originate from native point defects in β-Ga2O3 near the junction interface. Under a high forward current stress of 1000 A/cm2, device failure is found to be located at the edge region with the thinnest NiO, which is likely to be caused by the injection of hot electrons that diffuse across the entire NiO layer. Overall, the magnitude of parametric shift is approaching or comparable to those reported in the native SiC and GaN p–n junctions, suggesting that the NiO/β-Ga2O3-based UWBG devices have good potential to achieve a reliability comparable to their WBG counterparts.
Charge-mediated electric control of the perpendicular magnetic anisotropy in Fe–Ga/PMN-PT composite multiferroic
Authors: Tortarolo M. , Goijman D. , Barral M. A. , Di Napoli S. , Pérez Martínez A. A. , Ramírez G. , Sarmiento Chavez A. , Gómez J. , Zakharova A. , Bayram S. E. , Stramaglia F. , Vaz C. A. F. , Milano J. , Piamonteze C.
Published: January 2025

We present an experimental study of the magnetoelectric coupling in the Fe-Ga/Pb[(Mg1/3Nb2/3)O3]0.68-[PbTiO3]0.31 thin-film multiferroic composite using x-ray magnetic circular dichroism and ferromagnetic resonance (FMR). Our measurements show evidence for a charge-mediated coupling mechanism, suggested by the asymmetric magnetic remanence (Mrem) behavior under opposite electric fields (±E) and the asymmetric resonance field (Hr) in the FMR measurements. Also, the FMR measurements reveal a perpendicular magnetic anisotropy that can be related to an interface charge effect and it is tunable by the E field. Ab initio calculations support the existence of a charge-mediated coupling at the Fe–Ga/PMN-PT interface.
Aerodynamic effects of propeller slipstream on a transition micro aerial vehicle under various maneuvering conditions
Authors: Arumugam Vinoth Raj , Chidambaram Senthilkumar
Published: January 2025

This study examines the influence of propeller slipstream on the aerodynamic performance and longitudinal static stability of the Transition Micro Aerial Vehicle (TMAV), highlighting its role in advancing design and control strategies for Micro Aerial Vehicles. The objective is to assess the impact of propeller slipstream on the aerodynamic efficiency and static stability during various flight maneuvers. Wind tunnel experiments were conducted on a fixed-wing TMAV at a freestream velocity of 15 m/s, covering three propeller advance ratios (0.65, 0.55, 0.45), angles of attack from −8° to +16°, and tail deflection angles of −8°, 0°, and 8°. Computational fluid dynamics simulations for an advance ratio of 0.45 were also performed to validate experimental findings and analyze flow physics. The results reveal that the propeller slipstream significantly influences aerodynamic performance, reducing lift and increasing drag, which degrades longitudinal stability in maneuvering conditions. Drag coefficients increased by up to 43.98%, while the maximum lift-to-drag ratio decreased by 38.66% compared to unpowered cases. Lift forces dropped by 37.86% during level flight and 19.74% during pitch-up maneuvers but rose by 25.98% in pitch-down maneuvers. The starboard wing generated consistently higher lift than the port wing due to asymmetrical aerodynamic effects from the slipstream. Variations in lift and drag on the X-tail fins were strongly affected by interactions between the slipstream and wing downwash. These findings provide critical insights for optimizing TMAV design and enhancing stability in propeller-driven flight.
Dynamics of binary fluid convection in a rectangular container with a large aspect ratio
Authors: Li Xu-Long , Zheng Lai-Yun , Zhao Bing-Xin , Liu Don
Published: January 2025

This paper examines the formation and characteristics of Rayleigh–Bénard convection in ethanol–water mixtures in a rectangular container with a large aspect ratio of 100. Using a high-accuracy numerical method, the governing hydrodynamic equations were solved, revealing three distinct convective states: double localized traveling waves (DLTWs), source defect undulation (SDU), and spatiotemporal grain boundary (SGB). The formation processes, influencing factors, and flow characteristics of these states are explored, along with the effects of varying Rayleigh numbers on the transitions between them. For DLTWs, we identify a logarithmic relationship between the rate of change in the convective region and the Rayleigh number. Stability at the wavefront is maintained as the concentration waveform leads the temperature waveform. In the case of SDU, the generation of defect undulations is linked to the group velocity of traveling waves. As the Rayleigh number increases, SDU transitions to SGB, while a decrease leads to a transition to traveling waves. For SGB, the flow characteristics are determined by the intensity of the rolls and the speed at which boundary rolls form. In states with unfixed defect positions, these defects migrate either toward the center of the container or toward the sidewalls at varying speeds over time.
Hydrogen-terminated single crystal diamond MOSFET with the dielectric of Ga2O3
Authors: Wang Yan-Feng , Wang Wei , Zhang Ming-Hui , Shao Guo-Qing , Zhao Xi-Xiang , Wang Hong-Xing
Published: January 2025

In this work, the first fabrication and investigation of normally-off single crystal hydrogen-sterminated diamond MOSFETs with Ga2O3 dielectric has been successfully carried out. 50-nm-thick Ga2O3 was deposited by electron-beam evaporation technique at room temperature. The maximum drain current was −36 mA/mm, which was 164 times larger than previous work. Based on the transfer characteristic curve, the threshold voltage, on/off ratio and extrinsic transconductance were −0.37 V, 2.3 × 107, and 9.8 mS/mm, respectively. The effective mobility of the MOSFET was calculated to be 264.1 cm2/V ⋅s at VGS = − 1 V. This work may significantly promote the application of H-diamond FETs.
3D metamaterial broadband microwave absorber covered by structural topology-based pixelated color-changing layer
Authors: Yang Junyi , Zhao Jiancun , Qiu Ye , Cai Yining , Li Xinting , Guo Yuhao , Wang Xiaodong , Li Ben , Li Wenli , Yu Yiting
Published: January 2025

With rapid advancement in ISR (intelligence, surveillance, and reconnaissance), the demand for multispectral stealth technology has become urgent. In the field of radar stealth, 3D metamaterial absorbers have garnered significant attention due to their ultra-wideband microwave absorption. However, they face the challenge of restricted multispectral-compatible stealth capabilities, elevating the risk of being detected under ISR technology. In this study, we propose a solution by covering the absorber with a structural topology-based pixelated color-changing layer (STPCL), providing environmental camouflage and enhancing absorption intensity. Multiwall carbon nanotubes/spherical carbonyl iron/silicone rubber composites and thermochromic capsules/polydimethylsiloxane composites are used to fabricate the absorber and the STPCL, respectively. The STPCL not only provides adaptive camouflage in grassland and desert environments but also increases the characteristic dimensions to tune the absorption peaks and incorporates a grading circuit with stepped impedance to enhance impedance matching. As a result, the absorption bandwidth is slightly extended from 3.28–40 to 2.87–40 GHz, while the average reflection loss is improved from −13.55 to −16.83 dB. This approach demonstrates the potential to enhance the functionality and adaptability of metamaterial microwave absorbers in diverse operational environments.
Dynamic domain motion enhancing electro-optic performance in ferroelectric films
Authors: Kondo Shinya , Okamoto Kazuki , Sakata Osami , Teranishi Takashi , Kishimoto Akira , Nagasaki Takanori , Yamada Tomoaki
Published: January 2025

With the rapid advancement of information technology, there is a pressing need to develop ultracompact and energy-efficient thin-film-based electro-optic (EO) devices. A high EO coefficient in ferroelectric materials is crucial. However, substrate clamping can positively or negatively influence various physical properties, including the EO response of these films, thus complicating the development of next-generation thin-film-based devices. This study demonstrates that reversible dynamic domain motion, achieved through substrate clamping, significantly enhances the EO coefficient in epitaxial ferroelectric rhombohedral Pb(Zr, Ti)O3 thin films, where the (111) and (111¯) domains coexist with distinct optical axes. In principle, this approach can be applied to different film-substrate systems, thereby contributing to the advancement of sophisticated EO devices based on ferroelectrics.
Method to avoid crosstalk for induced flow acceleration in multi-stage dielectric barrier discharge plasma actuators
Authors: Nakamura Yoshinobu , Fujino Takayasu , Segawa Takehiko
Published: January 2025

Dielectric barrier discharge plasma actuators are flow control devices that can actively induce a flow using electrohydrodynamic force. This Letter proposes a configuration of multi-stage dielectric barrier discharge plasma actuators to accelerate the induced flow velocity. In the proposed configuration, the encapsulated and exposed electrodes between adjacent units of the multi-stage plasma actuator are interconnected and share the same potential, thereby avoiding crosstalk phenomena. The thrusts, cross-sectional flow velocity distributions, discharge images, and electric field distributions are examined for the conventional and proposed multi-stage plasma actuators. The results show that the proposed configuration can increase the thrust and induced flow velocity efficiently compared to the conventional one. The discharge images also show that no crosstalk occurs in the proposed configuration. This is mainly due to the low electric field strength in areas where crosstalk would occur.
Coexistence of multiple electronic and phononic nodal lines in a two-dimensional macroporous carbon material
Authors: Kong Weixiang , Wei Juan , Xiao Xiaoliang , Wang Rui , Wu Xiaozhi
Published: January 2025

Investigations into topological materials typically emphasize either electronic or phononic properties in isolation, often disregarding their coexistence, which could restrict the full realization of their practical applications. Here, we investigate HOD-graphene, an emergent macroporous carbon material featuring a unique configuration of hexagonal, octagonal, and dodecagonal carbon rings. This distinctive structure imparts exceptional mechanical properties to the material. Using a combination of first-principles calculations and symmetry analysis, we demonstrate that HOD-graphene hosts multiple nodal lines within both its electronic and phononic spectra. For the electronic bands, three nodal lines and several Dirac points manifest near the Fermi energy, generating unconventional electronic properties and distinct topological characteristics. Likewise, the phonon spectrum displays pronounced nodal lines, intricately associated with the material's vibrational modes. Our findings provide a promising platform for exploring the coexistence of electronic and phononic multiple nodal lines in two-dimensional materials, opening avenues for realizing exotic quantum phenomena.
Experimental observation of mutual coupling in resonator array on thin-metal-film
Authors: Ayyagari Surya Revanth , Indrišiūnas Simonas , Basharin Alexey , Janonis Vytautas , Pashnev Daniil , Ducournau Guillaume , Kuzhir Polina , Kašalynas Irmantas
Published: January 2025

We present the experimental observation of electromagnetic mutual coupling in an array of ring-shaped resonators (meta-atoms) fabricated on a free-standing thin metal film using a maskless direct laser ablation technique. The transmission spectra of various resonator configurations were measured via terahertz time-domain spectroscopy and a vector network analysis. Numerical modeling of periodically arranged resonators, employing multipole decomposition, revealed a clear dependence of inter-element coupling on the number of meta-atoms in the array. Theoretical analysis of electric and magnetic dipoles and quadrupoles elucidates the nature of resonance peak splitting and broadening, resulting in a reduction in the quality factor as the number of meta-atoms increases. We anticipate that observed inter-element coupling behavior along with multipole mode analysis could advance the development of multi-pixel emitters, 2D plasmonic THz sources, sensors, electro-optical modulators, and resonators for subwavelength photonic and plasmonic applications.
Low-pressure CVD grown Si-doped β-Ga2O3 films with promising electron mobilities and high growth rates
Authors: Khan Saleh Ahmed , Ibreljic Ahmed , Margiotta Stephen , Bhuiyan A. F. M. Anhar Uddin
Published: January 2025

In this work, we systematically investigated the growth of Si-doped β-Ga2O3 films using low-pressure chemical vapor deposition (LPCVD) system, achieving high room-temperature Hall mobilities of 162 and 149 cm2/V·s at carrier concentrations of 1.51 × 1017 and 1.15 × 1017 cm−3, respectively, for homoepitaxial (010) β-Ga2O3 film grown on β-Ga2O3 substrates and heteroepitaxial (2¯01) β-Ga2O3 film grown on off-axis c-sapphire substrate with 6° miscut-representing the highest mobilities reported for LPCVD-grown β-Ga2O3 materials. Carrier concentrations were precisely tuned by varying SiCl4 flow rates at a growth temperature of 1000 °C, resulting in concentrations ranging from 1.15 × 1017 to 1.19 × 1019 cm−3 as confirmed by both Hall and capacitance–voltage (C–V) measurements. The films exhibited high crystalline quality, confirmed by high resolution x-ray diffraction and Raman spectroscopy, indicating phase purity and structural integrity. Surface morphologies characterized by field-emission scanning electron microscope and atomic force microscopy showed a strong correlation between carrier concentrations and surface smoothness, with lower concentration resulting in reduced RMS roughness. Secondary Ion Mass Spectrometry analysis revealed uniform Si incorporation, with low carbon, hydrogen, and chlorine impurities below detection limits, indicating high purity of the films. A high low-temperature peak mobility exceeding >843 cm2/V·s was achieved at a carrier concentration of 1.74 × 1016 cm−3 for a (2¯01) β-Ga2O3 heteroepitaxial film at 80 K, highlighting the high purity and low compensation of these films. These findings emphasize the potential of LPCVD growth system for producing high-purity β-Ga2O3 films with thickness ranging between ∼2.3 and 11.7 μm and faster growth rates (∼4.7–17 μm/h), promising transport properties, controllable doping, and scalability for developing high-power vertical devices.
Perspectives on various-temperature stability of p-i-n perovskite solar cells
Authors: Tang Ying , Liu Yufang , Li Meng
Published: January 2025

Despite the significant breakthroughs in photoelectric conversion efficiency achieved by perovskite solar cells, their temperature stability remains a significant bottleneck to commercialization. Temperature fluctuations typically lead to structural changes and phase transformations in perovskites. Additionally, thermal stress can facilitate ion migration within the perovskite material, resulting in interface charge accumulation and electrode corrosion, which ultimately undermines the performance of perovskite devices. This brief perspective systematically discusses the mechanisms behind device performance degradation under temperature cycling conditions and presents potential improvement strategies to address these issues. Finally, we elaborate on the future challenges that must be overcome for the successful commercialization of these devices.
Amorphous-dominated MgO hollow spheres enhanced fluoride adsorption: Mechanism analysis and machine learning prediction
Authors: Fan Lin , Wang Dexi , Yu Honglei , Guo Jinyuan , He Yan
Published: January 2025

Amorphous-dominated magnesium oxide hollow spheres (A-MgO) were prepared using a spray-drying method in this study. These hollow spheres exhibited excellent sphericity, large specific surface areas, and abundant porosity. A-MgO exhibited outstanding fluoride adsorption properties, with a maximum adsorption capacity of 260.4 mg/g. When the pH value was less than 8, the fluoride removal percentage remained more than 87.4%. Moreover, the removal percentage remained above 75% even after five application cycles. In addition, the research revealed that SO42−, CO32−, and PO43− exerted a more pronounced effect on fluoride removal, whereas coexisting ions such as Br−, Cl−, NO3−, and HCO3− had minimal impact on this process. An in-depth analysis of the adsorption mechanism demonstrated that the process of fluoride adsorption by A-MgO involves various synergistic mechanisms, such as electrostatic adsorption, ion exchange, oxygen vacancy adsorption, physical adsorption, and pore filling. To predict the fluoride ion adsorption performance of A-MgO under complex conditions, a high-performance machine learning model, GBDT-S, was developed using hyperparameter optimization. The R2 of 0.99 and 0.80 for the training and testing datasets, respectively, with the RMSE of 3.26 and 3.89. Interpretative analysis using SHapley Additive exPlanations technology indicated that reaction time, PO43− concentration, and pH were key factors influencing the fluoride ion removal percentage.
On the effects of Reynolds number on the aerodynamic characteristics of streamlined box girders
Authors: Han Yuan , Sun Yifei , Liu Qingkuan , Jing Hongmiao , Huang Hanjie , Li Zhen , Wang Yangxue
Published: January 2025

The streamlined box girder is widely used in long-span bridges, yet the impact of Reynolds number effects on its aerodynamic characteristics is still not fully understood. This study focused on the streamlined box girder of the Ningbo Xiangshan Harbor Bridge, using a 1:15 scale model tested in the 8 × 6 m wind tunnel in Mianyang, China, under various angles of attack and high-Reynolds numbers (up to Re = 1.09 × 106). The findings indicate that the mean aerodynamic force coefficient exhibits significant Reynolds number effects at positive angles of attack, with maximum variations reaching 84.00%. The fluctuating force coefficient shows a trend of initially decreasing and then increasing with the increase in Reynolds number across all angles of attack. As the angle of attack increases from 0° to 8°, the distribution of mean and fluctuating wind pressure changes significantly. The mean wind pressure coefficient on the upper surface of the upstream nozzle decreases significantly with increasing Reynolds number at positive angles, with the rate of decrease increasing with the angle of attack and reaching a maximum of 0.81, which explains the Reynolds number effect on the mean aerodynamic force coefficient. At the +5° angle of attack, the fluctuating wind pressure distribution decreases and then increases with Reynolds number; at other angles, it generally decreases with increasing Reynolds number. The wind pressure correlation between circumferential measurement points increases with Reynolds number. The spanwise correlations of the lift and moment coefficients exhibit the same trend, with maximum increases of 0.60 and 0.69, respectively.
Controlling crystal planes of biomass-derived carbon based Mo2C NPs and the electrochemical performance
Authors: Du Yuxuan , Ahmed Md. Maruf , Xing Tian , Chen Shuwei , Du Jianping
Published: January 2025

The electrochemical property of Mo2C nanoparticles (NPs) depends on the structure and crystal planes. Herein, Mo2C nanoparticles were prepared and dispersed on carbon nanosheets by the construction of a biomass-derived carbon precursor, and the exposed dual crystal planes were also controlled by optimal conditions. The structure, compositions, and morphology of the carbon-based Mo2C were characterized, and the Mo2C NPs were well dispersed on the carbon nanosheets. The electrochemical study shows that optimal Mo2C exhibits excellent electrochemical properties for the oxidation of nicotine compared with other materials in the broad linear range of 0.2–300 μM. In particular, it displays a remarkable oxidation ability for the low-concentration nicotine (0.2–5 μM), and the detection limit is about 0.17 μM. Furthermore, the exposed dual crystal planes of Mo2C play a critical role in the oxidation. Notably, this characteristic of Mo2C NPs makes it possible to detect nicotine from the extracted solution and be used for chip electrodes to detect nicotine quickly via wireless response, which exhibits actual application prospects for portable detection. The results indicate that the as-prepared Mo2C material could be effective and low-cost for nicotine analysis in the sectors of health management and medical fields.
Analysis of the convective heat transfer performance of multi-morphology lattice structures in thermal management of high-speed aircraft
Authors: Zhang Yu , Yang Yue , Chen Geng , Jiang Qi , Hao Bo
Published: January 2025

The triply periodic minimal surface (TPMS) is considered an ideal choice for constructing surface structure of high-speed aircraft due to its excellent convective heat transfer. In recent years, multi-morphology TPMS structures have attracted increasing attention in various fields, as they offer superior and more desirable properties compared to traditional TPMS structures with uniform units. However, the relationship between different morphologies of TPMS and their thermodynamic performance has not been extensively studied. This paper proposes a method to quantitatively analyze the heat dissipation performance of different lattice structures. We compared the heat transfer performance parameters of six minimal surface lattice structure models through experiments and simulations, finding a strong correlation between experimental and simulation results. The results indicate that under flow rate conditions of 2.08–4.58 m/s, the Gyroid-Sheet model exhibits the highest comprehensive heat transfer coefficient. Compared to the Gyroid-Solid, Primitive-Solid, Primitive-Sheet, IWP-Solid, and IWP-Sheet models, the comprehensive heat transfer coefficient increased by 15.2–20.1%, 212.6–277.9%, 110.2–137.6%, 12.5–25.7%, and 31.3–54.6%, respectively. Additionally, under the same experimental conditions, we compared the comprehensive heat transfer coefficients of the multi-morphology Gyroid-Primitive model and the Gyroid-Sheet model. The results show that the combined Gyroid-Primitive model has a comprehensive heat transfer coefficient that is 10.5–16.1% higher than that of the Gyroid-Sheet model alone. This study lays the groundwork for the application of lattice structures in surface structure of high-speed aircraft and provides a basis for meeting the design and manufacturing requirements for future lightweight structures with high heat dissipation capabilities.
Tuning the superconducting dome in granular aluminum thin films
Authors: Deshpande Aniruddha , Pusskeiler Jan , Prange Christian , Rogge Uwe , Dressel Martin , Scheffler Marc
Published: January 2025

The peculiar superconducting properties of granular aluminum, which consists of nanometer-sized aluminum grains separated by aluminum oxide, are attractive for applications in quantum circuitry, and they are interesting from a fundamental materials physics view. The phase diagram of granular aluminum as a function of normal-state resistivity features a superconducting dome with a maximum critical temperature Tc well above the Tc=1.2K of pure aluminum. Here, we show how the maximum Tc of this superconducting dome grows if the substrate temperature during deposition is lowered from 300 K to cooling with liquid nitrogen (150 and 100 K) and liquid helium (25 K). The highest Tc that we observe is 3.27 K. These results highlight that granular aluminum is a model system for complex phase diagrams of superconductors and demonstrate its potential in the context of high kinetic inductance applications. This is augmented by our observation of comparably sharp superconducting transitions of high-resistivity samples grown at cryogenic temperatures and by a thickness dependence even for films substantially thicker than the grain size.
Preface to special topic: Plasma physics of the Sun in honor of Eugene Parker
Authors: Mauel Michael , Bale S. D. , Fox Nicola J. , McComas David , Velli Marco
Published: January 2025

This Special Topic commemorates the legacy of Eugene Parker and highlights new understandings of the plasma physics of the Sun resulting from the observations, plans, and analyses for the Parker Solar Probe (PSP) and Solar Orbiter (SolO) Missions. In recognition of Eugene Parker's remarkable insights and many contributions, distinguished authors from around the world were invited to present papers in theoretical, computational, and observational heliophysics and astrophysics. A total of 80 authors from 12 countries (Argentina, Czech Republic, France, Germany, Greece, India, Italy, New Zealand, People's Republic of China, Spain, United Kingdom, and United States of America) contributed to the Special Collection. These papers bring the recent research in physics of the Sun to the broader plasma physics community. Many include the latest observations from PSP and SolO and describe new understandings of coronal processes, solar wind structure and dynamics, transient events including nanoflares, and insights into stellar equilibrium and flows.
A phase transition in diffusion models reveals the hierarchical nature of data
Authors: Sclocchi Antonio , Favero Alessandro , Wyart Matthieu
Published: January 2025

Understanding the structure of real data is paramount in advancing modern deep-learning methodologies. Natural data such as images are believed to be composed of features organized in a hierarchical and combinatorial manner, which neural networks capture during learning. Recent advancements show that diffusion models can generate high-quality images, hinting at their ability to capture this underlying compositional structure. We study this phenomenon in a hierarchical generative model of data. We find that the backward diffusion process acting after a time
t
is governed by a phase transition at some threshold time, where the probability of reconstructing high-level features, like the class of an image, suddenly drops. Instead, the reconstruction of low-level features, such as specific details of an image, evolves smoothly across the whole diffusion process. This result implies that at times beyond the transition, the class has changed, but the generated sample may still be composed of low-level elements of the initial image. We validate these theoretical insights through numerical experiments on class-unconditional ImageNet diffusion models. Our analysis characterizes the relationship between time and scale in diffusion models and puts forward generative models as powerful tools to model combinatorial data properties.
MYO7A is required for the functional integrity of the mechanoelectrical transduction complex in hair cells of the adult cochlea
Authors: Underhill Anna , Webb Samuel , Grandi Fiorella C. , Jeng Jing-Yi , de Monvel Jacques B. , Plion Baptiste , Carlton Adam J. , Amariutei Ana E. , Voulgari Niovi , De Faveri Francesca , Ceriani Federico , Mustapha Mirna , Johnson Stuart L. , Safieddine Saaid , Kros Corné J. , Marcotti Walter
Published: January 2025

Myosin-VIIA (MYO7A) is an unconventional myosin responsible for syndromic (Usher 1B) or nonsyndromic forms of deafness in humans when mutated. In the cochlea, MYO7A is expressed in hair cells, where it is believed to act as the motor protein tensioning the mechanoelectrical transducer (MET) channels, thus setting their resting open probability (

P
o

). However, direct evidence for this unique role for an unconventional myosin in mature hair cells is lacking. Here, we show that MYO7A has a distinct role in hair cells, being crucial for the structural integrity of hair bundles. Postnatal deletion of
Myo7a
leads to 87 to 96% reduction in MYO7A from hair cells by postnatal day 20 (P20), without affecting hearing function. During the following week, mice showed progressive decline in both hearing function and MET current amplitude in hair cells without affecting the resting

P
o

and calcium sensitivity of the MET channel. Hair-bundle stiffness was normal at P20 but halved at P30, despite it having a normal staircase morphology and tip links. The reduction of MYO7A in the stereocilia (>87%) increased their vulnerability to sound-induced damage, with significantly more hearing loss and hair bundle deterioration than in control mice. RNA-sequencing identified a downregulation of several stereociliary genes in the
Myo7a
-deficient cochlea, indicating the presence of indirect compensatory mechanisms. This study reveals that mature hair cells seem to use a MYO7A-independent mechanism to maintain the resting

P
o

of the MET channels. Instead, MYO7A is essential for maintaining the structural and functional integrity of the hair bundles.
Time evolution of a pumped molecular magnet—A time-resolved inelastic neutron scattering study
Authors: Reeder T. R. , Titum Paraj , Kindervater J. , Stewart V. J. , Ye Q. , Rodriguez-Rivera J. A. , Qiu Y. , Maliszewskyj N. , McQueen T. M. , Broholm C. L.
Published: January 2025

Introducing an experimental technique of time-resolved inelastic neutron scattering (TRINS), we explore the time-dependent effects of resonant pulsed microwaves on the molecular magnet Cr
8
F
8
Piv
16
. The octagonal rings of magnetic Cr
3+
atoms with antiferromagnetic interactions form a singlet ground state with a weakly split triplet of excitations at 0.8 meV. A 4.6 tesla field was applied to tune the splitting between two members of the triplet excited level

|
1
⟩
↔
|
2
⟩

to resonance with 105 GHz (0.434 meV) microwaves. The time-dependent occupations of the ground state

|
0
⟩

, lower lying levels

|
1
⟩

and

|
2
⟩

, and higher energy states

|
λ
≥
3
⟩

were extracted during and after 20 s long microwave pulses incident along the (101) direction of a Cr
8
F
8
Piv
16
crystal held at 1.9 K. At significantly elevated spin temperatures, we found underpopulation relative to thermal equilibrium of

|
2
⟩

and spin-lattice thermalization time scales ranging from 1.6(2) s to 5.7(2) s depending on the power level. This contrasts with the relaxation time

τ
1

(
T
→
0
)

=
27

(
5
)

μ

s inferred for

|
2
⟩

from in situ Electron Spin Resonance measurements. By probing a broad range of excited states during intense microwave pumping, TRINS thus provides a first view of long lived excited states in a molecular antiferromagnet.
Highly ordered porous membranes for fabrication of multilayered nanostructures with perpendicular magnetic anisotropy
Authors: Kasiuk J , Khoroshko L , Baglov A , Akulich V , Bayev V , Do K T , Nguyen T H , Vu H K , Zhyhulin D V , Nguyen T N Anh
Published: January 2025

In this research, we describe the technology of fabrication of double-sided nanoporous alumina membranes with an ordered pore arrangement, adjustable pore size and smoothed surface relief, which allows maintaining the perpendicular magnetic anisotropy (PMA) of [Co/Pd] multilayers deposited over them. Their fabrication includes several important technological processes, namely two-step anodization of aluminum foil and subsequent ion-beam etching, which together allow for effective control of the morphology of the formed membranes. It is demonstrated that the adjustability of the anodization process allows for the control of the basic characteristics of the porous structure of the membrane, including cell and pore size, as well as its properties, including its flexibility and transparency, through alteration of the voltage and selection of an appropriate electrolyte. Simultaneously, ion-beam treatment is able to modify significantly the surface relief of membranes that facilitates their adaptation to the requirements of potential applications. The implemented transfer of the uniform porous morphology from the membrane to the deposited film accompanied by the conservation of PMA of the latter opens up opportunities of creating nanostructured magnetic media on porous alumina membranes which can be applicable in flexible spintronic devices.
The Book of Troilus, and Criseyde
Authors: Ashe Laura
Published: January 2025

This chapter analyses Chaucer’s Troilus and Criseyde in comparison with its sources, Boccaccio’s Filostrato and Benoît de Sainte-Maure’s Roman de Troie, and in light of the influence of Guillaume de Machaut and Dante. It argues that in changes he made to the representation of the characters of Troilus and Criseyde, Chaucer sought to develop a theory of human love, in the absence of a genuine theory of (individual, non-substitutable, and mortal) human love in medieval culture and thought. In depicting Troilus’ love of Criseyde as wholly freely willed, and unchanged by her betrayal, Chaucer offered a depiction of human love that shows the force of our ethical obligations to others, and exposes the Boethian directive to rise above the things of this world as profoundly inhumane: for the most important things of this world are other people. It is further argued that Chaucer’s representation of Criseyde is the effective mimesis of our real-world encounter with another, fundamentally unknowable, subjectivity; that Troilus is uniquely shown to succeed in the ethical recognition of Criseyde’s independent subjectivity; and that in itself constitutes an act of love. Finally, these developments formulate Troilus and Criseyde as a new kind of tragedy, standing against both the classical tragedy of fixed fate and destructive anagnorisis, and the Christian divine comedy by which all is resolved in eternity. Troilus shows the human tragedy of mortality, and the human dignity of freely willed love in the face of that mortality.
Imagining Malaya
Authors: Keo Bernard Z
Published: January 2025

Over the course of British colonial rule in Malaya, the Peranakan Chinese (hereafter referred to as Peranakan) attempted to bring to life a complex imagination of nationhood predicated on an inclusive and multi-ethnic approach to integrating Malaya’s plural society. A creolized community borne of intermarriage between Chinese migrants anqd indigenous Malays, Peranakan ideas of nationhood and belonging were influenced by their liminality. In word and deed, Peranakan political actors campaigned for the extension of citizenship rights to all those domiciled in Malaya regardless of race, class, or religion. Yet, this political history has largely been overlooked. In examining the Peranakan imaginary of the nation, Imagining Malaya explores one of the many alternatives of a Malayan nation that were imagined—and were possible at one point or another—that have yet to be studied. Centring the Peranakan into Malaysia’s story of decolonization and nation-making, it casts a new light on Malaysia’s path to nationhood and who is included—and excluded—within that story. The book examines Peranakan politics in Malaya from the arrival of the British on Penang Island in 1786 to the end of British rule in Malaya upon the latter’s independence on 31 August 1957, focussing primarily on the community’s political activities during Malaya’s complex path to merdeka (independence). This monograph reveals how seemingly disparate political acts by the Peranakan were in reality bound together by a cosmopolitan sense of identity and belonging as leading figures from the community sought to build an inclusive Malayan nation.
Malaya Transformed
Authors: Keo Bernard Z
Published: January 2025

In response to the rapid loss of Malaya and Singapore to the Japanese during World War II, British colonial planners in London devised comprehensive reforms for Malaya underpinned by the creation of a new unified administrative structure, the Malayan Union. The sudden end of the war in 1945 caught the British unawares and resulted in a violent interregnum between the surrender of Japanese forces and the restoration of British rule in Malaya. The violence of the interregnum served as a catalyst for Peranakan opposition to Penang and Malacca’s connection to the Malay States as part of the Malayan Union in 1946. The subsequent intensification of ethnic Malay nationalism in response to the Union, coupled with Singapore’s exclusion from the new administrative entity, exacerbated Peranakan anxieties about their place in the new Malaya. Investigating the development of these concerns and anxieties, this chapter locates the origins of Peranakan political activism in the post-World War II period and highlights how this developed in opposition to the intensification of ethnonationalist sentiments during the short-lived Malayan Union experiment.
Epilogue
Authors: Keo Bernard Z
Published: January 2025

Since Malaya’s independence in 1957, the Peranakan seemingly experienced a radical transformation in identity. What was once a politically active community has, over the last sixty years or so, become a predominantly cultural one that has been appropriated by the state as a cultural heritage product to sell the idea of Malaysia’s success as a multicultural country on the global tourism marketplace. This brief Epilogue discusses the depoliticization and commodification of the Peranakan by the Malaysian (and Singaporean) states, examining how the Peranakan have been remembered and forgotten in the public imagination, focussing particularly on how they have been portrayed in museums and in popular literature.
Accounting for local incidence when estimating rotavirus vaccine efficacy among countries: a pooled analysis of monovalent rotavirus vaccine trials
Authors: Amin Avnika B , Waller Lance A , Tate Jacqueline E , Lash Timothy L , Lopman Benjamin A
Published: January 2025

Rotavirus vaccine appears to perform sub-optimally in countries with higher rotavirus burden. We hypothesized that differences in the magnitude of rotavirus exposures may bias vaccine efficacy (VE) estimates, so true differences in country-specific rotavirus VE would be exaggerated without accommodating differences in exposure. We estimated VE against any-severity and severe rotavirus gastroenteritis (RVGE) using Poisson regression models fit to pooled individual-level data from Phase II and III monovalent rotavirus vaccine trials conducted between 2000 and 2012. The standard approach model included terms for vaccination, country, and a vaccination-country interaction. Other models used proxies for exposure magnitude like severe RVGE rate or age at severe RVGE instead of country. Country-specific proxies were calculated from placebo group data or extracted from an external meta-analysis. Analyses included 83,592 infants from 23 countries in the Americas, Europe, Africa, and Asia. Using the standard approach, VE against severe RVGE substantially varied (10-100%). Using the severe RVGE rate proxy brought VE from all but two countries between 80% and 86%. Heterogeneity for VE against any-severity RVGE was similarly attenuated. Adjusting for exposure proxies reduced heterogeneity in country-specific rotavirus VE estimates. This phenomenon may extend to other vaccines against partially immunizing pathogens with global disparities in burden.