Browse Articles

Bayesian analysis of viscous modified cosmic Chaplygin gas in FRW universe with a cosmological constant

High-Q short-wave mid-infrared silicon microring resonators based on foundry processes

Short-wave mid-infrared (SWMIR, 2.0–2.5 μm) photonics has diverse applications in free-space communications, LiDAR, and environmental monitoring. Silicon photonics with mature device fabrication processes and cost efficiency has emerged as a promising platform for SWMIR applications. Among various functional components, microring resonators stand out as essential elements for on-chip SWMIR systems due to their capability in wavelength filtering, sensing, and signal modulation. However, the large-scale fabrication of such devices, particularly those with high-quality-factors (Q-factors), remains a significant challenge. Here, we developed SWMIR high-Q silicon waveguide-integrated resonators based on a multi-project wafer (MPW) foundry service. Ridge and strip waveguides exhibit propagation losses of 1.22 and 1.37 dB/cm. Moreover, racetrack resonators were demonstrated with an intrinsic Q of ∼0.9 × 106 in the SWMIR waveband. The study presents a promising proof-of-concept demonstration of high-performance SWMIR silicon photonic devices using an MPW foundry process, highlighting the potential for scalable fabrication and providing a solid foundation for future application-specific integrated photonic systems.

A blockchain-driven forensic framework for secure cyberbullying evidence collection in IoT environments

Defect-mediated remarkable ionic conductivity in undoped nickel oxide at low temperature

Undoped nickel oxide (NiO) is conventionally known as a p-type semiconductor with dominant hole transport. However, for the first time, this study reveals an exceptionally high ionic conductivity in dense, undoped NiO ceramic at remarkably low temperature of 375 °C. High density NiO ceramics (relative density > 97%) sintered at 1300 °C demonstrate ionic conductivity σ ∼ 5 × 10−3 S/cm at 375 °C, surpassing many conventional solid oxide fuel cells applications and leveling up to the performance of lithium (Li)-based solid electrolytes at comparable temperatures. The temperature-dependent DC conductivity relation follows Arrhenius behavior with an activation energy of ∼0.78 eV. Impedance spectroscopy analysis reveals a systematic evolution from semicircular to characteristic teardrop-shaped Nyquist plot (Z″ vs Z′) with increasing temperature, indicating the emergence of ambipolar transport. In situ x-ray diffraction at high temperatures demonstrates lattice expansion and increasing non-stoichiometry with temperature due to the formation of cation vacancies that facilitate ion migration. Chronoamperometric transference number measurements yield an ionic transference number of approximately 0.98, indicating that ionic transport constitutes the dominant contribution to the measured conductivity. UV-Visible absorption spectroscopy and photoluminescence spectroscopy further identify sub-bandgap defect states and defect-related transitions arising from strong hole-phonon coupling. The combined structural, electrical, and optical evidence establishes defect-mediated ionic transport as the origin of the remarkable conductivity. These findings position undoped NiO as a promising low-temperature ionic conductor for next-generation material for electrochemical energy conversion.

Adaptive deep reinforcement learning–based secure routing for wireless sensor networks

Tailored crystal structure via Zr-chemistry in Na3V2(PO4)3 cathodes for high-performance Na-ion storage

In this work, a Zr-chemistry modulation approach is presented to precisely alter the electronic structure of Na3V2(PO4)3 (NVP) via atomic-level doping under controlled conditions. Our findings reveal that Zr substitution triggers a significant anisotropic expansion along the c axis, thereby enhancing Na+ diffusion pathways. Additionally, in situ x-ray diffraction reveals that the expanded pathway facilitates a transition from a three-phase process to a two-phase process during operation, significantly enhancing structural reversibility and stability. Benefiting from this structural design, the optimized NVP cathode exhibits excellent Na-ion storage performance, achieving a high specific capacity of 110.3 mA h g−1 at 0.2 C and retaining 78.6 mA h g−1 after 1000 cycles at 20 C, corresponding to 87.1% capacity retention.

Research on loss optimization calculation and cooling structure design of high-speed permanent magnet motor rotor for integrated starter-generator

A Reversible 900 nm Near‐Infrared Photoswitch for Invisibly Writable 2D and 3D Displays

ABSTRACT Molecular photoswitches interchange between different states in response to light irradiation and represent prominent tools to deliberately control changes at the smallest scales. A standing challenge for their development is pushing absorptions into the low‐energy end of the electromagnetic spectrum, which is highly desirable to avoid photodamage, allows mixing of photoresponsive components, and maximizes the available color range. Here we report on a novel photoswitch motif, peri ‐benzo[ a ]fluoranthenethioindigo (PBFT), enabling direct excitation with near‐infrared (NIR) light up to 900 nm wavelengths in a fully reversible fashion. PBFT provides an outstanding property profile with high isomer yields, good thermal bistability, and strongly distinct color changes from pale green to deep blue. Application within a commercially available and easy‐to‐use polymer material allows to realize reversible and spatially resolved inscription of information with extremely long wavelengths of light. Writing information into versatile handheld 2D and 3D optical displays and optical memories is thus possible with non‐damaging irradiation, invisible to the naked eye.

Phishing webpage detection using structured URL generation

Imbalance fault diagnosis based on iterative attention wavelet packet decomposition and weighted ensemble classification algorithm

Prioritising construction accident risk factors using an integrated Random Forest, XGBoost, and ANN framework with sensitivity analysis

TrafCopAgent: synergizing reinforcement learning and multi-agent collaboration for adaptive emergency traffic control

Diagenetic processes in quaternary vertebrate fossils from coastal environments

Abstract The fossilization of Quaternary mammals in coastal environments of southern Brazil results from the interaction between taphonomic and diagenetic processes, strongly controlled by hydrological dynamics, interstitial fluid chemistry, and sedimentary reworking. Through the integration of macro- and microscopic analyses with SEM, XRD, and Raman spectroscopy, two main diagenetic pathways — Route A and Route B — were identified. Route A develops in silica-rich environments, characterized by mechanical sediment infiltration and precipitation of siliceous phases. These processes promote increased structural disorder in apatite, reduction in crystallite size, pronounced removal of B-type carbonate, and the development of vibrational bands associated with phosphate–silicate interactions. In parallel, Route B is associated with carbonate-supersaturated solutions. In this pathway, calcite precipitation and the formation of larger crystallites indicate a buffered geochemical system capable of delaying apatite decarbonation. Evidence of this buffering is preserved in Raman data, which reveal a diagenetic gradient marked by narrowing of the ν₁(PO₄³⁻) band (decreased FWHM) together with progressive but partial depletion of B-type carbonate. XRD data confirm the formation of fluorapatite through diagenetic substitution of OH⁻ by F⁻, as well as variations in crystallite size consistent with distinct fluid–mineral interaction histories. Taphonomic evidence indicates variable redox conditions and intense pore-fluid circulation. The distinction between Route A and Route B provides a useful interpretative framework for understanding bone preservation in Quaternary coastal environments.

Inside Front Cover: Organic Intercalation Enables Controllable Single‐Atom Coordination for Efficient H ₂ O ₂ Electrosynthesis (Angew. Chem. Int. Ed. 31/2026)

LIR-Mamba: consolidating YOLO and selective SSM with global-local scanning for robust infrared small target detection under laser interference

Hydrodynamic characteristics during floating and installation of high blockage-ratio immersed tunnels in Inland Rivers

1‐D Collocated Dual‐Gradient Sensory Fibers for Comprehensive Sensing and Decoding of Complex Human Motion and Physiology

ABSTRACT Wearable interfaces that capture both weak physiological fluctuations and large body motions remain difficult to realize in a single fiber because most strain‐sensing fibers are governed by one dominant electromechanical response mode. Consequently, mechanically distinct deformation regimes are ambiguously represented, limiting sensing range and information quality for downstream motion interpretation. Here, we develop a monolithic dual‐gradient fiber with complementary sensing regimes programmed through coupled materials and process design. By jointly tuning the percolation behavior and rheological drawability of carbon black/carbon nanotube‐filled styrene–ethylene–butylene–styrene (SEBS) composites, we identified two formulations suitable for coaxial co‐drawing within one continuous strand. The resulting fiber pairs a highly responsive layer for small deformation with a robust layer that stays informative at larger strain, producing synchronized but nonredundant signals. At low strain (0%–10%), the high‐sensitivity layer exhibits a gauge factor of 51.28, over four times the low‐sensitivity layer (12.42), while the two layers remain functional up to approximately 40% and 160% strain, respectively. This architecture preserves mechanically salient features across distinct and superimposed inputs, supporting measurements from pulse and respiration to joint motion. In a single‐fiber glove, the dual‐sensitivity design improves gesture‐classification accuracy by more than 10% relative to single‐sensitivity controls, enriching features for decoding.

Toward Chromoselective Transformations in Biological Systems: Perspectives and Challenges

ABSTRACT Addressing small‐molecule chromophores with bioactive properties has been established as an effective means of controlling biological systems for several decades. However, the complexity of in vitro and especially in vivo systems cannot be matched by a single wavelength of light (de)activating one kind of chromophore. Consequently, developing methods to combine and individually control multiple chromophores within the same system is of high importance. An increasing number of strategies have become available relying on the chromoselective transformation of small molecules. This article features the chromoselective control of photoswitches, photoclick chemistry, and photocages, and highlights perspectives and future challenges to be overcome in the context of biological systems.

A graph-guided cross-modal attention network for multimodal emotion recognition via emotion-shift modeling

Biphasic High‐Entropy Heterojunctions Enabled by Perovskite Transformation

ABSTRACT High‐entropy materials (HEMs) provide an ideal platform for tailoring functional properties. However, the controlled synthesis of biphasic high‐entropy heterostructures with synergistic multifunctionality remains a significant challenge. We propose an in‐situ chemical reduction strategy driven by dynamic transformations, enabling the conversion of perovskite precursors into a series of anchored high‐entropy heterojunctions. Under reducing conditions, the entropy‐stabilized perovskite lattice acts simultaneously as both a structural scaffold and a compositional reservoir. Selectively, B‐site transition metal cations exsolve to form uniformly dispersed high‐entropy alloy (HEA) nanoparticles, whereas A‐site rare‐earth cations remain within the parent framework and transform into a high‐entropy oxide (HEO) support. This unique biphasic high‐entropy heterointerface effectively modulates the interfacial electronic structure and magnetic configuration, which not only enhances polarization loss via abundant heterogeneous interfaces and crystal defects, but also amplifies magnetic loss. The resultant HEA–HEO exhibits an impressive electromagnetic response, with its optimal effective absorption bandwidth showing a 176% and 242% enhancement over low‐entropy materials (La 2 O 3 ‐Co) and single‐phase high‐entropy materials (La 2 O 3 ‐HEA), respectively. In flexible composite films, the heterojunction promotes efficient conversion of electromagnetic energy into heat while enhancing thermal conductivity, thereby broadening pathways towards multifunctional high‐entropy heterojunction materials.