Energy Release Research Articles

Experimental Investigation of a Passive Compliant Torsional Suspension for Curved-Spoke Wheel Stair Climbing

Curved-spoke wheels have been proposed as an effective way to overcome stair-like obstacles with smooth, rotation-only motion. However, when the wheel’s contact point shifts, discontinuous changes in its radius of curvature cause abrupt drops in the robot’s linear speed, often leading to reduced payload stability and slip. As a result, maintaining reliable stair climbing becomes more difficult. At higher speeds, these sudden changes become stronger, further reducing dynamic stability. To address these issues, we propose a passive Compliant Spiral Torsional Suspension (C-STS) attached to the wheel’s drive axis. Through camera-based marker tracking, we analyzed wheel trajectories under various stiffness and speed conditions. In particular, we define the deceleration caused by the velocity drop during contact transitions as our dynamic stability metric and demonstrate that the C-STS significantly reduces this deceleration across low-, medium-, and high-speed climbing, based on comparisons both with and without the suspension. It also raises the average velocity, likely due to a brief release of stored elastic energy, and lowers the net torque requirement. Our findings show that the proposed C-STS greatly improves dynamic stability and suggest its potential for enhancing stair-climbing performance in curved-wheel-based robotic systems. Furthermore, our approach may extend to other reconfigurable wheels facing similar instabilities.

Discovery of Evolution of the Temporal Features of X-Ray Bursts from SGR J1935+2154

Abstract SGR J1935+2154 has undergone eight active episodes since its discovery in 2014. In this study, our focus is on the evolution of the temporal characteristics including burst duration, minimum variation timescale (MVT), and waiting time across these active episodes observed by Fermi/Gamma-ray Burst Monitor (GBM). We find a linear increase in the logarithmic mean of burst duration over time, with a deviation during the fourth and eighth active episodes containing X-ray burst (XRB)−Fast Radio Burst (FRB) 200428 and XRB−radio burst 221021 association events. We also find a possible increasing burst frequency, with the fourth active episode exhibiting an exceptionally high burst rate. Therefore, XRB−FRB 200428 is potentially triggered by energetic events such as a large crust, magnetic reconnection, or glitches. The MVT analysis reveals deviations in the sixth and seventh active episodes with ∼3σ. These results may suggest evolving magnetospheric field geometry, neutron star crust, and energy release mechanisms of SGR J1935+2154. Finally, our findings predict that longer XRB durations indicate the highly likely occurrence of XRB and radio burst association events, warranting focused multiwavelength observations during such episodes, which will also be further confirmed or disproved by future observations.

Influence of Multi‐Walled Carbon Nanotubes and Nano‐Tungsten Carbide Hybrid Fillers in Enhancing Wettability, Fracture Toughness, and Sorption Characteristics of Polypropylene Nanocomposites

ABSTRACTThis study focuses on the combined effect of MWCNT and WC on the properties of PP nanocomposites. The fracture toughness analysis revealed that the hybrid system with 1 wt% of WC and 2 wt% of MWCNT (1W2CP) showed the highest critical stress intensity factor and strain energy release rate with a plastic deformation radius of 6.4 × 10−3 mm. The fracture toughness properties obtained by numerical models were found to be in agreement with the experimentally obtained values. The contact angle measurements and surface energy calculations revealed that the hybrid system displays superior wettability and higher surface energy. The hybrid sample exhibited the lowest diffusivity of 1.10 × 10−7 m2/s as the meshed nanotubes and WC offer better sorption resistance to the transport of solvents. The hybrid system showed superior thermal resistance with Ea of 264 kJ/mol owing to the formation of a dual network by the nanofillers. The heterogeneous nucleation of WC and the transcrystallization effect of CNT amplified percentage crystallinity, which increased the shear viscosity of the sample. The hydrothermal aging showed that 1W2CP exhibited higher tensile strength and low toughness, as the slow heating from −20°C to 80°C helped in the rearranging of amorphous PP chains to semi‐crystalline ones.

Compressive properties analysis of mono-sized fragmented coal and rock

The compressive properties of fragmented coal and rock aggregates within goaf critically influences surface subsidence dynamics and reservoir development strategies. This study conducted constrained compression testing on mono-sized fragmented coal and rock particulate materials using a custom-designed compaction apparatus, evaluating parameters including compressive resistance, pre-/post-compaction mass variations, porosity evolution, and acoustic emission (AE) signatures. Experimental observations demonstrated progressive yet decelerating axial strain development under increasing stress, accompanied by diminishing porosity reduction rates. AE activity exhibited proportional escalation in both event frequency and energy release intensity during particle consolidation. Particle dimension inversely correlated with compaction strength, while fragmented coal generated higher AE responses compared to rock counterparts. Three distinct compression phases were identified: void compaction, pore compaction, and particle recombination. These findings establish mechanistic insights for optimizing goaf flow field modeling and backfill mining techniques through enhanced understanding of energy dissipation patterns in particulate media.

The Roles of Transcrustal Magma- and Fluid-Conducting Faults in the Formation of Mineral Deposits

In this article, we consider the roles of transcrustal magma- and fluid-conducting faults (TCMFCFs) in the formation of mineral deposits, showing the importance of deep sources of heat and hydrothermal solutions in the genesis and history of deposit formation. As a result of the impact on the lithosphere of mantle plumes rising along TCMFCFs, intense block deformations and tectonic movements are generated; rift systems, and volcanic–plutonic belts spatially combined with them, are formed; and intrusive bodies are introduced. These processes cause epithermal ore formation as a consequence of the impact of mantle plumes rising along TCMFCF to the lithosphere. At hydrocarbon fields, they play extremely important roles in conductive and convective heat, as well as in mass transfer to the area of hydrocarbon generation, determining the relationship between the processes of lithogenesis and tectogenesis, and activating the generation of hydrocarbons from oil and gas source rock. Detection of TCMFCFs was carried out using MMSS (the method of microseismic sounding) and MTSM (the magnetotelluric sounding method), in combination with other geological and geophysical data. Practical examples are provided for mineral deposits where subvertical transcrustal columns of increased permeability, traced to considerable depths, have been found; the nature of these unique structures is related to faults of pre-Paleozoic emplacement, which determined the fragmentation of the sub-crystalline structure of the Earth and later, while developing, inherited the conditions of volumetric fluid dynamics, where the residual forms of functioning of fluid-conducting thermohydrocolumns are granitoid batholiths and other magmatic bodies. Experimental modeling of deep processes allowed us to identify the quantum character of crystal structure interactions of minerals with “inert” gases under elevated thermobaric conditions. The roles of helium, nitrogen, and hydrogen in changing the physical properties of rocks, in accordance with their intrastructural diffusion, has been clarified; as a result of low-energy impact, stress fields are formed in the solid rock skeleton, the structures and textures of rocks are rearranged, and general porosity develops. As the pressure increases, energetic interactions intensify, leading to deformations, phase transitions, and the formation of chemical bonds under the conditions of an unstable geological environment, instability which grows with increasing gas saturation, pressure, and temperature. The processes of heat and mass transfer through TCMFCFs to the Earth’s surface occur in stages, accompanied by a release of energy that can manifest as explosions on the surface, in coal and ore mines, and during earthquakes and volcanic eruptions.

Seismic Activity Analysis in Indonesia: Integrating Machine Learning, Geospatial Data, and Environmental Factors for Risk Assessment

Earthquake’s phenomena are critical for understanding Earth's interior, tectonic processes, and disaster preparedness. Because of indonesia location in the Pacific Ring of Fire, it’s suffering from regular seismic activities which result in huge annual losses. This study investigates the earthquake data from 1992 to 2024 by applying clustering techniques such as K-means and geodata visualization. By integrating physics, geospatial analysis, and machine learning, the study processes earthquake data to calculate energy release and analyze spatial-temporal patterns. Principal Component Analysis (PCA) is applied to reduce data dimensionality, while K-Means clustering identifies seismic patterns based on magnitude, depth, and energy. Visual tools, including correlation heatmaps and spatial maps, are used to present findings that support earthquake risk management in Indonesia.The results reveal temporal patterns in earthquake activity, with peaks observed in 2004–2007, associated with significant seismic energy release. Spatial analysis highlights high energy concentrations in megathrust zones. PCA and K-Means clustering identify three distinct clusters with varying correlations between seismic and atmospheric variables, indicating the influence of thermal and tectonic factors. These insights contribute to seismic hazard mapping, risk reduction strategies, and the improvement of earthquake prediction models. Future research should extend datasets and refine machine learning techniques to achieve more accurate predictions.

Magnetic Reconnection in a Compact Magnetic Dome: Chromospheric Emissions and High-velocity Plasma Flows

Abstract Magnetic reconnection at small spatial scales is a fundamental driver of energy release and plasma dynamics in the lower solar atmosphere. We present observations of a brightening in an active region, captured in high-resolution data from the Daniel K. Inouye Solar Telescope using the Visible Broadband Imager and the Visible Spectro-Polarimeter (ViSP). The event exhibits Ellerman bomb−like morphology in the Hβ filter, associated with flux cancellation between a small negative-polarity patch and an opposite polarity plage. Additionally, it displays enhanced emissions in Ca ii K, hot elongated features containing Alfvénic plasma flows, and cooler blueshifted structures. We employ multiline, nonlocal thermodynamic equilibrium inversions of the spectropolarimetric data to infer the stratification of the physical parameters of the atmosphere. Furthermore, we use the photospheric vector magnetogram inferred from the ViSP spectra as a boundary condition for nonlinear force-free field extrapolations, revealing the three-dimensional distribution of squashing factors. We find significant enhancements in temperature, velocity, and microturbulence confined to the upper photosphere and low chromosphere. Our findings provide observational evidence of low-altitude magnetic reconnection along quasi-separatrix layers in a compact fan-spine-type configuration, highlighting the complex interplay between magnetic topology, energy release, and plasma flows.

Merging plasmoids and nanojet-like ejections in a coronal current sheet

Forced magnetic reconnection is triggered by external perturbations, which are ubiquitous in the solar corona. This process plays a crucial role in the energy release during solar transient events, which are often associated with electric current sheets (CSs). The CSs can often disintegrate through the development of the tearing instability, which may lead to the formation of plasmoids (magnetic islands, or twisted flux ropes in 3D) in the nonlinear phase of evolution. However, the complexity of the dynamics and the magnetic and thermodynamic evolution due to the coalescence of the plasmoids are not fully understood. We explore the departure of the CS from its equilibrium configuration through a reconnection process characterized by the formation of plasmoids with a guide field, their mutual approach and eventual coalescence, and we investigate the complex magnetic topology and thermodynamic evolution in and around the merged plasmoids. We used a resistive magnetohydrodynamic simulation of a 2.5D current layer embedded in a stratified medium in the solar corona, incorporating field-aligned thermal conduction using the open-source code MPI-AMRVAC. Multiple levels of adaptive mesh-refined grids were used to resolve the fine structures that result during the evolution of the system. The instability in the CS was triggered by imposing impulsive velocity perturbations concentrated at three different locations in the upper half along the CS plane. This led to the formation of plasmoids and their later coalescence. We demonstrate that a transition from purely 2D reconnection to 2D reconnection with a guide field takes place at the interface between the plasmoids as the latter evolve from the pre-merger to the merged state. The small-scale, short-lived, and collimated outflows during the merging process share various physical properties with the recently discovered nanojets. The subsequent thermodynamic change within and outside the merged plasmoid region is governed by the combined effect of Ohmic heating, thermal conduction, and expansion/contraction of the plasma. Our results imply that impulsive perturbations in coronal CSs can be the triggering agents for the coalescence of plasmoids. This then leads to the subsequent magnetic and thermodynamic change in and around the CS.

Study on Rock Fracture Mechanism Using Well Logging Data and Minimum Energy Consumption Principle: A Case Study of Mesozoic Clastic Rocks in Chengdao–Zhuanghai Area, Jiyang Depression

In the Chengdao–Zhuanghai area, there are few core samples of Mesozoic clastic rocks but abundant logging data. It is difficult to establish a fracture model of clastic rocks directly based on core samples and relevant tests. In this study, triaxial compression tests are conducted on Mesozoic clastic rock samples to reveal the failure mechanism of clastic rocks. A statistical model based on logging data is utilized to calculate dynamic rock mechanical parameters, and theoretical relationships between static and dynamic mechanical parameters are derived. A failure model for clastic rocks is established using logging data and the minimum energy consumption principle by applying the principle of minimum energy consumption and adopting the unified energy yield criterion of rocks as the energy consumption constraint. This research study shows that a linear relationship exists between the static and dynamic mechanical parameters of Mesozoic clastic rocks, and the correlation coefficient can reach 85%. The core aspect of clastic rock failure is energy dissipation. As confining pressure increases, more energy must be dissipated during the failure of clastic rocks. Upon failure, the releasable elastic energy accumulated within the clastic rocks clearly reflects the confining pressure effect. A higher initial confining pressure leads to a greater release of elastic energy and results in a more severe failure degree. The developed rock failure model effectively represents the nonlinear mechanical behavior of Mesozoic clastic rocks in the Chengdao–Zhuanghai area under complex stress conditions. It is suitable for investigating the fracture distribution of Mesozoic clastic rocks and addresses the challenge of understanding the failure mechanism of these rocks in the Chengdao–Zhuanghai region.

Ignition and Combustion Characteristics of Micro‐Aluminum and Nano‐Aluminum Mixture

ABSTRACTWhile prior studies focus on individual aluminum powders, the combustion behavior of mixed nano‐ and micron‐sized aluminum particles remains unclear. This work investigates combustion characteristics of aluminum powders with different particle size combinations (29 µm, 15 µm, 1 µm, and 100 nm) under two conditions: a pure composition and a mass ratio of 72.2% micron‐sized particles to 27.8% nano‐sized particles. Additionally, the combustion characteristics of aluminum powders with best combustion performance particle size combinations were analyzed under six different oxidation environments (O₂, N₂, and CO₂) and various packing densities. The results indicate that the mixed aluminum powder with a 72.2% mass ratio of 29 µm particles and 27.8% mass ratio of 100 nm particles exhibits the best overall combustion performance. Among the six oxidizing atmospheres, the mixed aluminum powder demonstrated the highest combustion performance in a pure oxygen environment. The combustion performance of mixed aluminum powder is most effective at a density of 2.9 g/cm3. The combustion performance of aluminum powder is significantly enhanced when nano‐ and micron‐sized aluminum powders are mixed. This improvement is attributed to the synergistic benefits of combining the two sizes, where nano‐sized aluminum, with its high specific surface area, facilitates rapid oxidation kinetics and intense combustion, while also generating more gaseous products that boost thrust. Conversely, micron‐sized aluminum provides effective heat conduction and stability, acting as a thermal reservoir that prolongs combustion duration and mitigates agglomeration. This system enables quick ignition and a balanced release of energy, optimizing both reaction efficiency and thrust stability.

Coronal dimmings from active region 13664 during the May 2024 solar energetic events

Coronal dimmings are regions of transiently reduced brightness in extreme ultraviolet (EUV) and soft X-ray (SXR) emissions associated with coronal mass ejections (CMEs), providing key insights into CME initiation and early evolution. During May 2024, AR 13664 was among the most flare-productive regions in recent decades, generating 55 M-class and 12 X-class flares along with multiple Earth-directed CMEs. The rapid succession of these CMEs triggered the most intense geomagnetic storm in two decades. We study coronal dimmings from a single active region (AR 13664) and compare them with statistical dimming properties. We investigate how coronal dimming parameters -- such as area, brightness, and magnetic flux -- relate to key flare and CME properties. We performed coronal dimming detection on observations from the Atmospheric Imaging Assembly (AIA) instrument on board the Solar Dynamics Observatory (SDO). We used a logarithmic base-ratio thresholding technique to identify dimming regions, selecting pixels where log (I/I_0) ≤ -0.19. Due to the high activity of the AR, we propose a quantitative threshold for distinguishing real mass depletion dimmings from unrelated intensity reductions by setting a threshold on the dimming area reached within the first hour (A≥6.48 km^2). We systematically identified all flares ≥M1.0, all coronal dimmings and all CMEs (from the CDAW SOHO/LASCO catalogue) produced by AR 13664 during 2024 May 1 - 15, and studied the associations between the different phenomena and their characteristic parameters. We detect coronal dimmings in 22 events, with 16 occurring on-disc and six off-limb. Approximately 83% of X-class flares and 23% of M-class flares are associated with CMEs, with 13 out of 16 on-disc dimmings linked to CME activity. The dimmings in AR 13664 exhibit total unsigned magnetic fluxes exceeding $5.5 $ Mx, reflecting the region's high magnetic flux density; and dimming areas greater than 1.16 km^2. Previous statistical studies had shown a correlation between dimming parameters and flare parameters. We find that dimming parameters for the May 2024 events, particularly total dimming area and area growth rate, have a stronger correlation with GOES soft X-ray peak flux and fluence than anticipated, highlighting the connection between energy release in flares and the accompanying dimming. We find correlations between dimming properties and CME maximum velocities, which indicate that coronal dimmings serve as proxies for CME speeds. Our results support the strong interplay between coronal dimmings and flares, as we find increased correlations between flare and dimming parameters in this single-AR study compared to the general dimming population. Furthermore, we confirm that coronagraphic observations, unable to observe the lower corona, underestimate correlations between CME velocities and dimming parameters, as they fail to capture the early CME acceleration phase. This highlights the critical role of dimming observations in providing a more comprehensive understanding of CME dynamics.

Investigating the Influence of Axial Velocity and Tangential Velocity on Combustion Characteristics in a Cylindrical Vortex Combustor

Efficient combustion is essential for various applications, including gas turbines, industrial furnaces, and propulsion systems. The interaction between axial and tangential velocities significantly influences combustion stability, flame shape, and pollutant formation. However, a comprehensive understanding of these effects in a cylindrical vortex combustor remains elusive. The primary of this study is to analyse how axial and tangential velocities impact combustion characteristics within the Cylindrical Vortex Combustor (CVC). Specifically, we aim to determine the optimal velocity combination that ensures stable combustion, minimal emissions, and efficient energy release. The CVC geometry was modelled, and the simulations were conducted for various axial and tangential velocity combinations by Computational Fluid Dynamics (CFD) simulations using ANSYS Fluent software were employed to explore the behaviour of the vortex combustor under varying conditions. The Navier-Stokes equations, energy equation, and species transport equations were solved. Air inlet conditions included a mass flow rate of 40 mg/s and for fuel inlet was set 3.0 to 4.0 mg/s through an equivalence ratio (j) ranging from 0.5 to 1.5. The numerical findings indicate higher axial velocities enhance mixing and promote stable combustion and this velocity component excessive lead to flame blowout. The tangential velocities influence vortex strength and flame stability and will enhances recirculation and flame anchoring. Due to these conditions, an optimal balance between axial and tangential velocities yields efficient combustion. Understanding the interplay between axial and tangential velocities is essential for designing efficient vortex combustors. The findings provide valuable insights for optimizing combustion systems, reducing emissions, and improving overall performance.

Hamiltonian energy and coexistence of spiral wave patterns in lattice array from bidirectional coupled neurons

Abstract In this study, we explore a Hindmarsh–Rose model to evaluate the impacts of asymmetric coupling, mutual interference, and external magnetic flux, as these factors play crucial roles in neurons dynamics. The performance of these networks is largely dependent on the coupling between neural oscillators. The entire neuron model’s dynamical behavior is altered when an electrical synapse connection has an asymmetric coupling. More complicated behaviors will be displayed by neuron models exposed to magnetic flux induction with such asymmetric synaptic coupling. As a result, we provide a coupled neuron model that takes into account asymmetric electrical synapses and flux coupling. The different dynamic features of the coupled Hindmarsh–Rose neuron model are investigated by taking the coupling, diffusion, and flux coupling coefficients constant into performance as the control factors. We have demonstrated that the integration of magnetic flux that enters the neuronal model can significantly attenuate spiral wave activity within the network. This approach mitigates the propagation of these waves and enhances the stability of the neural network. The supply and release of energy are significant for the functioning of individual neurons and neural networks. This paper investigates the Hamiltonian energy of neurons under electromagnetic induction, offering new insights into the interaction between neuronal dynamics and external electromagnetic fields.

Evaluation of the Effect of Fuzhuan Brick Tea on Bread Quality and In Vitro Digestion.

In this study, the chemical constituents, quality and functional characteristics of the mixture of Fuzhuan brick tea and wheat bread (2:100, 4:100, 6:100, 8:100, 10:100) were investigated to guide the production of slow-digested wheat bread. The dough fermentability, the content of free sulfhydryl groups and wet gluten, specific volume, sensory evaluation were determined to evaluate the influence of Fuzhuan brick tea on wheat bread quality. When the ratio of tea to water was 6:100, the dough fermented faster, and the resulting bread, with the flavor of Fuzhuan brick tea, was of higher quality and more acceptable to consumers. Further activity studies showed that the water extract of Fuzhuan brick tea (WFT) had a good inhibitory effect on α-amylase and amyloglucosidase, which could slow down the digestion of bread in the intestines. When the ratio of tea to water was 6:100, more slowly digestible starch in the bread was produced, allowing for a steady and prolonged release of energy. The results suggested that Fuzhuan brick tea is suitable for the development of functional wheat bread in terms of bread processing, quality and healthy diet structure.

Experimental Investigation on Thermal and Ignition Characteristics of Direct Current (DC) Series Arc in a Lab-Scale Photovoltaic (PV) System

This study investigates the thermal behavior and ignition dynamics of DC series arcs in a lab-scale photovoltaic (PV) system. The impacts of current magnitude, dynamic current variations, and electrode gap on electrode surface temperatures are analyzed, while ignition characteristics of common electrical materials (PC, PVC, XLPO, PPE, etc.) are investigated by analyzing critical time thresholds during the arc-induced combustion. Results show that electrode surface temperatures rise with increased current or larger electrode gaps, driven by the enhanced DC arc energy release. Dynamic current variations (increasing/decreasing) shift the balance between heat accumulation and dissipation, resulting in the nonlinear temperature evolution. Additionally, the peak temperature of the anode is about 50% higher than that of the cathode due to the electron flow-driven heat transfer and particle collisions. Notably, general electrical materials can be ignited successfully by stable DC arcs. The anode can ignite flame-retardant materials within 3 s, while the cathode takes a relatively long time to ignite, approximately 20 to 30 s. Besides, enlarged electrode gaps can induce a mutual reinforcement between arcs and flames, resulting in further stabilized arcs and intensified flames. This highlights potential elevated fire hazards as the connector gap increases due to the DC arc erosion.

First-Principles Calculations of the Effect of Ta Content on the Properties of UNbMoHfTa High-Entropy Alloys

Uranium-containing high-entropy alloys (HEAs) exhibit great potential as a novel energetic structural material, attributed to their excellent performance in impact energy release, superior mechanical properties, and high density. This study investigates the effects of Ta content on the phase stability, lattice constant, density, elastic constants, polycrystalline moduli, and electronic structure of (UNbMoHf)54−xTax high-entropy alloys (where x = 2, 6, 10, 14, 18), utilizing a combination of density functional theory (DFT) calculations and the special quasi-random structure (SQS) approach. Our findings confirm that these alloys maintain stable body-centered cubic structures, as evidenced by atomic radius difference and valence electron concentration evaluations. Analysis of elastic modulus, Cauchy pressure, and Vickers hardness indicates that Ta incorporation enhances mechanical properties and increases the anisotropy of these alloys. Furthermore, investigations into the electronic structure reveal that adding Ta reduces metallic character while increasing covalent characteristics, enhancing the contribution of Ta’s d-orbitals to the total density of states and intensifying covalent bonding interactions between Ta and other elements such as Nb, Mo, and U. These findings provide theoretical guidance for the design of high-performance UNbMoHfTa HEAs with tailored properties.

Bioinspired nondissipative mechanical energy storage and release in hydrogels via hierarchical sequentially swollen stretched chains

Nature suggests concepts for materials with efficient mechanical energy storage and release, i.e., resilience, involving small energy dissipation upon mechanical loading and unloading, such as in resilin and elastin. These materials facilitate burst-like movements involving high stiffness and low strain and high reversibility. Synthetic hydrogels that allow highly reversible mechanical energy storage have remained a challenge, despite mimicking biological soft tissues. Here we show a synthetic concept using fixed hydrogel polymer compositions based on sequentially swollen and sequentially photopolymerized gelation steps for hierarchical networks. The sequential swellings facilitate the balance of properties between resilience and dissipation upon controlling of the chain extension. At low hierarchical levels, we show resilience with small hysteresis with increased stiffness and resilient energy storage, whereas at high hierarchical levels, a transition is shown to a dissipative and considerably reinforced state. The generality of this approach is shown using several photopolymerizable monomers.

Reconnection Nanojets in an Erupting Solar Filament with Unprecedented High Speeds

Abstract Solar nanojets are small-scale jets generated by component magnetic reconnection, characterized by collimated plasma motion perpendicular to the reconnecting magnetic field lines. As an indicator of nanoflare events, they are believed to play a significant role in coronal heating. Using high-resolution extreme-ultraviolet imaging observations from the Extreme Ultraviolet Imager on board the Solar Orbiter mission, we identified 27 nanojets in an erupting filament on 2024 September 30. They are potentially associated with the untwisting of magnetic field lines of the filament. Most nanojets exhibit velocities around 450 km s−1, with the fastest reaching approximately 800 km s−1, significantly higher than previously reported but comparable to the typical coronal Alfvén speed. To our knowledge, these are the highest speeds ever reported for small-scale jets (less than ∼1 Mm wide) in the solar atmosphere. Our findings suggest that these nanoflare-type phenomena can be more dynamic than previously recognized and may contribute to the energy release process of solar eruptions and the heating of coronal active regions.

ANTIMATTER: THE POTENTIAL IMPACT ON THE FUTURE OF MEDICAL AND PHARMACEUTICAL INDUSTRIES

Antimatter comprises antiparticles that mirror ordinary matter in mass but exhibit inverted quantum properties, such as charge. Theoretical predictions by Paul Dirac in 1928 laid the groundwork for its discovery, which Carl Anderson achieved experimentally in 1932 through positron detection in cosmic ray studies. Subsequent discoveries of antiprotons and antineutrons further solidified the concept of antimatter. Antimatter is produced in high-energy particle accelerators, cosmic ray interactions with Earth's atmosphere, and certain types of radioactive decay. Particle accelerators, such as linear accelerators, cyclotrons, synchrotrons, betatrons, Cockcroft-Walton generators and Van de Graaff generators, play a crucial role in antimatter production and research. This property makes antimatter both a potential energy source and a subject of safety concerns due to the immense energy release upon annihilation. Storing antimatter safely involves sophisticated techniques like magnetic traps, magnetic bottles and electrostatic traps, which prevent antimatter from coming into contact with matter. The study of antimatter also addresses fundamental questions in physics, such as the matter-antimatter asymmetry in the universe. Despite the challenges in production, storage, and handling, ongoing research aims to unlock the secrets of antimatter and harness its potential for scientific and practical advancements. This review highlights the history, production methods, potential applications and challenges associated with antimatter, emphasizing its significance in both fundamental research and potential technological innovations. Peer Review History: Received 13 February 2025; Reviewed 12 March 2025; Accepted 14 April; Available online 15 May 2025

Single Cu Atoms Anchored Energetic COFs as Combustion Catalytic Promoters toward Rapid and Concentrated Thermal Decomposition of Ammonium Perchlorate.

Achieving a synergistic, rapid, and concentrated energy release process of ammonium perchlorate (AP) is of vital significance for boosting the thrust of composite solid propellants. However, conventional catalytic promoters often exhibit suboptimal catalytic kinetics due to inefficient utilization of active sites. Herein, atomically dispersed Cu-coordinated covalent organic frameworks (COFs)-based catalytic promoters are reported, decorating with energetic anion groups. The highly accessible single Cu sites confined in the COFs significantly contribute to the raid and concentrated energy release of AP, yielding a sharply narrowed decomposition peak at 341.3°C with a peak width of only 9°C. This performance is markedly superior to the dispersed exothermic process of raw AP (410.3°C with a peak width of 30°C). Additionally, the energetic COF promoter considerably increased the output energy via collaboratively promoting the chemical energy release of AP and its own decomposition. Correlating in situ spectroscopies and theoretical calculations reveals that the incorporated anionic groups effectively modulate the local electronic structure of the Cu sites. This alteration promotes the key step of cleavage of Cl─O bonds in AP intermediates to produce reactive oxygen species and also boosts the oxidation of NH3 to high-valence nitrogen oxides, thereby accelerating the combustion reaction kinetic.